description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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FIELD OF INVENTION
[0001] The present invention relates to dishware; more specifically, it relates to systems and methods for providing stackable dishware.
BACKGROUND OF THE INVENTION
[0002] Many cultures use dishware such as bowls, plates, cups, ashtrays, and coasters, while also using various instruments such as knives, forks and spoons to aid in cutting, arranging, and consuming food. The dishware is typically sold in sets having limited matching designs, sizes, and shapes. For instance, a set may have a number of small plates, a number of large plates, a single size of bowls, and a single size of glasses. Even dishware sold separately is often standardized so as to conform to other typical dishware. These dishware sets, as well as individually sold dishware, present a number of problems.
[0003] First, dishware sizes within a set often do not address the various consumption needs for a given user. For example, the user might wish to serve a quantity or size of food that is too large to be reasonably served on a smaller plate, yet too small to be reasonably served on a larger plate. Accordingly, several unfortunate situations may result.
[0004] First, the user may choose to use the smaller plate and reduce the quantity or size of food that the user serves in order to fit the capacity of the smaller plate. This situation may result in the appetite of the user not being satisfied. Second, the user may choose to use the larger plate and either increase the amount of food the user serves or choose to keep the quantity or size of food the same. If kept the same, the presentation of the food may not be ideal or esthetically pleasing. If the quantity or size of food is increased, it may lead to overeating or waste of food that is not eaten because of an inappropriate food proportion in relation to the appetite of the user. Finally, the user may choose to not consume or serve the food at all, which would also result in an unsatisfied appetite.
[0005] Therefore, the standardized size of dishware, either in sets or sold independently, presently leads to instances where a user experiences an inadequate satiation of appetite or an eating experience that is not esthetically pleasing.
[0006] Next, it is difficult to efficiently and securely store dishware. This problem is present with dishware sets and is even more pronounced with individual non-standardized pieces. Typically, similarly sized dishware is stacked with the base of one dishware resting on the top of the dish are below it. Other common sized dishware is stacked similarly in proximate positions. Non-standard sized dishware is often stored independently. First, this storage methodology takes up space and is inefficient. Second, this configuration is not secure, and the plates can easily shift and slide resulting in damage.
[0007] Furthermore, the traditional storage method of dishware, either stacked or placed alone, leaves the consumption surface of the dishware in contact with the open air, which creates issues of hygiene and cleanliness. As a result of the contact with the open air, dust, debris, airborne bacteria and viruses can freely contact the dishware. The longer the dishware is stored, the greater the likelihood that users of the dishware will be exposed to undesirable particles or pathogens.
[0008] In short, traditional dishware suffers from being limited to standardized sizes, inefficient to store, easily damaged when stored, and open to particles and pathogens. This invention solves these and many other problems.
SUMMARY
[0009] The present invention relates to dishware; more specifically, it relates to systems and methods for providing stackable dishware. In one embodiment, the invention includes a plurality of stackable dishware, the stackable dishware comprising a first dishware and a second dishware, the second dishware configured to being stackable adjacent to the first dishware, wherein the first and second dishware are configured to define a three dimensional shape when stacked.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Preferred and alternate embodiments of the present invention are described in detail below with reference to the following drawings:
[0011] FIG. 1 is a top view of a plurality of stackable dishware, in accordance with an embodiment of the invention;
[0012] FIG. 2 is a perspective view of the plurality of stackable dishware, in accordance with an embodiment of the invention;
[0013] FIG. 3 is an exploded view of the plurality of stackable dishware, in accordance with an embodiment of the invention;
[0014] FIG. 4 is a side view of the plurality of stackable dishware, in accordance with an embodiment of the invention;
[0015] FIG. 5 is a cross section of the plurality of stackable dishware, in accordance with an embodiment of the invention;
[0016] FIG. 6 is a close-up cross section of the perimeter a single internal dishware, in accordance with an embodiment of the invention; and
[0017] FIG. 7 is a close-up cross section of the perimeter of two stacked internal dishware, in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
[0018] The present invention relates to dishware; more specifically, it relates to systems and methods for providing stackable dishware. Specific details of certain embodiments of the invention are set forth in the following description and in FIGS. 1-7 to provide a thorough understanding of such embodiments. The present invention may have additional embodiments, or may be practiced without one or more of the details described for any particular described embodiment.
[0019] FIG. 1 is a top view of a plurality of stackable dishware 100 , in accordance with an embodiment of the invention. The stackable tableware 100 includes a top cap dishware 110 , a plurality of internal dishware 120 , and a seam 130 .
[0020] In one embodiment, the cap dishware 110 is placed adjacent to the internal dishware 120 and the internal dishware 120 is placed adjacent to other internal dishware 120 and a bottom cap dishware (not shown). The placement of the dishware results in the seam 130 that is shown in the illustration. Any of the cap dishware 110 , the internal dishware 120 , or the bottom cap dishware may be removed by simply lifting the adjacent dishware.
[0021] In another embodiment, any of the dishware may include a plate, a bowl, an ashtray, a cup, a coaster or any other dishware. In yet another embodiment, the stackable dishware may define any shape including a cube, rectangular cube, sphere, or other non-uniform shape.
[0022] In a still further embodiment, there may be no internal dishware, and the plurality of stackable dishware comprises a bottom cap dishware and a top cap dishware.
[0023] In a yet further embodiment, there may be any number of internal dishware and single pieces of internal dishware may be removed such that the three dimensional shape that results from stacking does not lose its continuity.
[0024] FIG. 2 is a perspective view of the plurality of stackable dishware 100 , in accordance with an embodiment of the invention. The stackable dishware includes the cap dishware 110 , a plurality of internal dishware 120 , and a seam 130 , which is a result of the dishware being adjacent to each other.
[0025] FIG. 3 is an exploded view of the plurality of stackable dishware 100 , in accordance with an embodiment of the invention. FIG. 3 depicts the cap dishware 110 and a plurality of internal dishware 120 . The internal dishware 120 includes various sizes of plates. Each plate includes an outer ridge that serves as a barrier for food during consumption and/or a structural support while stacked adjacent to other dishware. In certain embodiments, any of the dishware includes bowls, plates, coasters, cups and other dishware. In one particular embodiment, the plurality of stackable dishware 100 further includes areas for utensils, measuring tools, knives, or other cooking, bar-tending, or serving device, either internally or externally.
[0026] FIG. 4 is a side view of the plurality of stackable dishware 100 , in accordance with an embodiment of the invention. The stackable dishware includes the cap units 110 , a plurality of internal units 120 , and a seam 130 , which results from the dishware being stacked. In this embodiment, the seam 130 that results from the dishware being stacked is at various angles to the ground including parallel and non-parallel angles.
[0027] FIG. 5 is a cross section of the plurality of stackable dishware 100 , in accordance with an embodiment of the invention. FIG. 5 similarly depicts the cap dishware 110 , a plurality of internal dishware 120 , and a seam 130 , which results from the dishware being stacked.
[0028] FIG. 6 is a close-up cross section of the outer rim of one internal dishware 120 , in accordance with an embodiment of the invention. In one embodiment, the outer rim of the one internal dishware 120 comprises a lip 140 , a depression 150 , and a base 160 . The base 160 creates a limited surface on the bottom perimeter of the internal dishware suitable for contacting a surface that the internal dishware may be placed upon.
[0029] In further embodiments the base may be any shape, such as a triangle or square, oval or hexagon. In a yet further embodiment, the base is not contiguous along the full perimeter of the internal dishware and comprises of a plurality of protrusions that may be in any shape, such as a point, hemisphere, cube or rectangle and in any configuration on the bottom of the internal dishware. In a still further embodiment the base is absent.
[0030] FIG. 7 is a close-up cross section of the outer edge of two internal dishware 120 , in accordance with an embodiment of the invention. In one embodiment, the seam 130 is defined by the junction of a lip 140 on one of the plurality of a first internal dishware 120 joining a depression 150 in a second adjoining internal dishware 120 .
[0031] In one particular embodiment, the seam 130 is air tight. In certain embodiments, the air tightness is achieved using a rubber or foam liner along the lip of the edge of the dishware or within the depression or both. In another embodiment, the dishware is snapped together using internal or external fasteners (not shown). In yet a further embodiment, the dishware is leaned together rather than stacked, such as to form a pyramid or other shape. In this embodiment, a frame may be added for support as necessary.
[0032] In another embodiment the seam 130 is created by any configuration of lip and matching depression or any other suitable method of coupling adjoining dishware. Suitable means of coupling adjoining dishware include, but are not limited to, slots, pins, grooves, indentations, notches, and complementary shaping.
[0033] In another embodiment, the plurality of stackable dishware 100 includes plates. In a still further embodiment, the plurality of stackable dishware 100 includes bowls. In an even further embodiment, the plurality of stackable dishware 100 includes plates and bowls.
[0034] In a further embodiment, the plurality of stackable dishware 100 includes one or more of any type of dishware including, but not limited to, cups, bowls, plates, saucers, dishes, platters, trays, mugs and boats. The any type of dishware may be any of the plurality of internal dishware 120 or the cap dishware 110 .
[0035] In a still further embodiment, the plurality of stackable dishware 100 may be made from one or more or a combination, mixture, or composite of glass, wood, paper, plastic, ceramic, stone, metal, porcelain, resin, or other material. In yet further alternative embodiments, one or more of the plurality of internal dishware 120 or the cap dishware 110 may include a texture, pattern, or image of any shape, color or size, either regular or irregular.
[0036] In a further embodiment, the plurality of stackable dishware 100 may resemble a regular three dimensional shape including but not limited to a sphere, oblong sphere, cube, cylinder, pyramid, tetrahedron, cones, or various types of prisms. In other embodiments, the plurality of stackable tableware may resemble irregular or amorphous three dimensional shapes or may be shaped to depict any person, place or thing, either real or fictitious.
[0037] In yet another embodiment, the plurality of stackable dishware 100 is designed such that one or more of the plurality of internal dishware 120 and the cap dishware 110 are stackable in a fashion wherein the edge of any individual dishware is perpendicular, parallel, or any other angle in relation to the ground. Moreover, the angles of relation to the ground need not be the same for any or all of the plurality of internal dishware 120 or the cap dishware 110 .
[0038] While preferred and alternate embodiments of the invention have been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of these preferred and alternate embodiments. Instead, the invention should be determined by reference to the claims that follow. | A plurality of stackable dishware, the stackable dishware comprising a first dishware and a second dishware, the second dishware configured to being stackable adjacent to the first dishware, wherein the first and second dishware are configured to defining a three dimensional shape when stacked. | 0 |
This is a continuation of application Ser. No. 878,225, filed Feb. 16, 1978 now abandoned.
BACKGROUND OF INVENTION
The present invention relates to solar energy collection and in particular to coatings for producing selective absorber surfaces.
A wide variety of solar collectors are presently available, which collectors may be classified into three major types. The first and essentially simplest type of collector is that of the non-tracking flat plate type, which consists essentially of a flat absorber panel enclosed in a collector housing having a window over the absorber, which structure is oriented towards the sun and usually remains fixed in position. This type of structure may be movable for adjustments during the solar year but for the most part it normally remains stationary during any particular period of collection, e.g., day, month, season or year. Another type of collector is that using an evacuated tube or tubes which surrounds an absorber surface. This type of collector normally is in a fixed position for a particular collection period as mentioned above but it has the advantage of having an evacuated space for reducing convection and conduction losses from the absorber surface. Yet another type of solar collector is the concentrating type which may include a flat plate or evacuated tubular collector located at a concentrating zone or focus of appropriate concentrating apparatus. The collector may be of the fixed type which has a relatively low concentration ratio, a wide acceptance angle for relatively long periods of the solar day and may require little or no tracking. On the other hand, the most sophisticated and expensive of the concentrating collectors are those having a relatively narrow acceptance angle with high concentration and which consequently require tracking over the entire period of the solar day.
Each of the aforementioned types of collectors serves a specific market. For example the non-tracking flat plate collector serves the domestic hot water and heating market, whereas the evacuated tubular type, whether fixed or partially tracking, may be used to produce hot water, heat and air conditioning. Finally, the highly concentrating tracking collectors may be utilized for the production of high temperature working fluid for power generation. It should be realized that each of the systems has constraints which are rather severe and that substantial cost reduction must be realized in order to economically justify a solar collector installation as an alternative to other sources.
To this end a spectrally selective absorber coating is an essential component of most efficient collector designs. Existing coatings, although quite efficient, as evidenced by high absorptivity α and low emissivity ε, are very expensive. Exotic and expensive materials such as indium, gold and silver compounds are sometimes used to produce spectrally selective absorber surfaces. Considering the square footage requirements of absorber surfaces which are necessary to compete with just the domestic hot water and heating alternatives, such exotic and expensive materials are not economically attractive.
It has been found that some films of metal oxides, when combined in proper juxtaposition, provide useful selective absorber surfaces, which surfaces are valuable improvements in the selective absorber technology, since they can be produced in large quantities at reasonable costs.
The type of surface contemplated by the present invention is one in which the absorptivity α is measured in the visible and near visible wavelengths of solar radiation from about 0.2 micrometers to about 2 micrometers, and the emissivity ε is measured in a range of the infrared and near infrared domain from about 2 micrometers to about 20 micrometers.
It is known that certain coatings for absorbers exhibit selectivity, in that they are opaque to incident solar radiation but on the other hand are transparent to infrared. For example, black chrome on copper has been found to absorb in the range of visible radiation with an absorptivity of 0.9 and the polished copper substrate "looks through" the black coating to reflect infrared radiation.
A rather comprehensive summary of some of the problems and phenomenon discovered in connection with selected coatings is discussed by Seraphin in an article entitled Converting Solar Radiation to Heat:Challenges to Optical Material Science, published in Optical Science Center Newsletter 10, No. 1, 1976, University of Arizona, Tuscon. Absorber-reflector tandems are discussed in that article wherein two basic configurations are described as follows: (1) heat mirrors, wherein the reflector intercepts the sunlight first, and are characterized by highly doped semiconductors such as indium oxide, tin oxide or cadmium stannate, which are highly reflective in the thermal infrared but are transparent to the incident solar energy; (2) absorber reflector configuration, wherein the absorber is transparent to longer wavelengths so that the reflector can "look through" and suppress the emittance in the thermal infrared. Other types of absorbers are discussed such as semiconductor absorbers and those having various controlled refractive indexes.
Nozic et al. in U.S. Pat. No. 3,987,781 discusses the use of a cadmium stannate electrically conductive coating which suppresses infrared radiation. Gillory in U.S. Pat. No. 3,981,293 discusses a figure of merit for absorption and reflection in a solar collector for a heat mirror window. Mochel, on the other hand, discusses in his U.S. Pat. No. 3,202,054 the use of multiple coatings for reflecting infrared radiation to suppress the heat buildup in a building due to incident sunlight. Similarly Dates in U.S. Pat. No. 3,473,944 describes a heat reflecting glass panel which reflects a substantial portion of radiation throughout the visible spectrum and also absorbs a certain amount of radiation so as to both prevent glare and permit the viewing of objects therethrough without color distortion. None of the aforementioned references show the arrangement of specially formulated coatings for a solar absorber as described herein.
It has been found that tin, indium and certain iron oxide coatings when combined in a tandem arrangement can act as both an absorber and as an infrared mirror, which coatings are relatively easy to apply to a substrate such as glass. On the one hand, tin oxide films have been used for infrared mirrors, but have not as yet been formed as effective absorbers. Iron oxide, however, has been found to be a reasonably good absorber but a poor infrared reflector.
The present invention seeks to utilize the materials set forth above in a manner which is an improvement over the described prior arrangements, since the materials serve a dual function of exhibiting high absorptivity in the visible range and good infrared reflectivity in the desired infrared range.
SUMMARY OF INVENTION
There has been provided composite coatings for solar collector absorber surfaces wherein solar radiation impinges on one surface of the absorber, which absorber is adapted to transfer energy so received from the impinging solar radiation in the form of sensible heat to a working fluid in contact with a delivery surface thereof comprising: a smooth surface absorber substrate having a first coating of metal oxides deposited on the smooth layer, which oxides are selected from the group consisting essentially of tin, antimony, indium and iron; and a second coating of metal oxides deposited on the first layer selected from the aforementioned group for said first layer; said first and second coatings deposited so as to exhibit a relatively high absorption characteristic α of at least 0.85 in the solar wavelength range of less than about 2 micrometers, and a relatively low emissivity characteristic ε of less than 0.2 within the wavelength range of the infrared greater than about 2 micrometers.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a greatly enlarged cross sectional view illustrative of a substrate material coated with the composite coating of the present invention, which substrate may form part of an absorber surface for various types of the solar collectors described herein.
FIG. 2 is a plot of data for Example 6 set forth hereinafter, illustrating an advantageous result of thin coatings.
FIG. 3 is a plot of solar reflectance of tin oxide vs. spray volume of solution.
FIG. 4 plots reflectivity of a composite fluorine duped tin oxide coating from Example 7 vs. film thickness in terms of volume and compares a plot of reflectivity for a composite film.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawing there is illustrated a substrate material 10, preferably glass, which has a delivery surface 11 disposed to be in contact with a working fluid WF, and another surface 13 disposed so as to face impinging radiation R. Deposited on the surface 13 of the substrate 10 is a first coating 12 which as hereinafter described, may be either a highly absorbent black body type coating, or a highly reflective infrared coating. The differences will be explained further in the discussion. Disposed in tandem on the first coating 12 is a second coating 14, which will exhibit properties opposed to that of the coating 12. In other words the coating 14 will be an absorber when the coating 12 is a reflector and vice versa. The reason for this is that in one case when the coating 14 is an infrared mirror and may be transparent to the visible portion of radiation R, that is in the wavelength range from about 0.2 to about 2 micrometers, and opaque to radiation of longer wavelengths up to about 20 micrometers, the coating 12 is virtually opaque to radiation in the aforementioned visible range and highly absorbent thereof. From this it can be realized that the impinging radiation R passes through the coating 14 and is absorbed by the coating 12, converted to a longer wavelength energy, and transferred by conduction through the substrate 12 to delivery surface 11 which is in contact with the working fluid WF as shown. The longer wavelength radiation, longer than 2 micrometers, is reflected from the interface 15 between the coatings 12 and 14 towards the coating 12 and substrate 10.
In a variation of the tandem coating arrangement, the surface 14 may be of a selected material which is opaque to visible radiation (i.e. an absorber) and transparent to infrared. The coating 12, on the other hand, would then be a suppressor of infrared radiation greater than 2 micrometers, and can "look through" the coating 14 to suppress radiation from the substrate 10, which radiation is transferred thereto by the conduction through the various coatings 14 and 12.
To illustrate the principles of the invention described herein the following examples are disclosed.
EXAMPLE 1
______________________________________(A) (i) Top Coating (14) Spray solution composition: α ε ##STR1## (ii) Bottom coating (12) Spray solution composition: ##STR2## .87 .59(B) (i) Top coating (14) .01 solution from above (ii) Bottom coating (12) .10 solution from above .92 .17______________________________________
In Example 1 above, it is clear that tin oxide coatings which have hereinbefore been most useful as low emissivity infrared suppressing coatings, may be combined with an antimony dopant to produce a highly absorbing coating as the antimony approaches approximately 10% by weight of the solution. The tin oxide coating may be used in combination with a magnetite coating (see Example 2 below), which is relatively easy to produce with an absorptivity greater than 0.85 and an emissivity less than 0.2.
EXAMPLE 2
______________________________________Magnetite-tin oxide coatings______________________________________(A) (i) Top coating (14) α Ε .01 solution from Example 1 (A)(ii) (ii) Bottom coating (12) Fe.sub.3 O.sub.4 .88 .19(B) (i) Top coating (14) Fe.sub.3 O.sub.4 (ii) Bottom coating (12) .01 solution from Example 1 (A)(ii) .87 .34______________________________________
EXAMPLE 3
To 7.0 ml of SnCl 4 solution (1.40 gm SnCl 4 .5H 2 O/ml in 1.5 HCl) was added 1.5 ml of 24.6% HF (49.2% HF diluted 1:1 in propanol-2). The solution was sprayed on a plate preheated to 650° C. The resulting film produces an emissivity ε of 0.11.
Thus the coating of this Example 3 may be substituted for top coating 14 in Examples 1 and 2.
In composite selective absorber films such as the one described in Examples 1 and 2 , the overall performance is improved as the emissivity ε of the top coating 14 is decreased, thus substitution of tin-doped indium oxide for antimony-doped tin oxide will improve the selective absorption efficiency of the composite coating. However, the much higher cost of InCl 3 as compared to SnCl 4 mitigates against its commercial use in this application where low cost is critical to successful development. A substantial reduction in indium salt consumption can be achieved by use of a relatively thin coating of indium-tin oxide deposited over a layer of the inexpensive tin-antimony oxide material.
EXAMPLE 4
A solution was prepared by adding 2.2 ml of SnCl 4 (0.10 gm/ml in EtOAc) to 14.0 ml of InCl 3 (0.50 gm/ml in EtOAc). This stock solution was diluted progressively and a 5 ml quantity sprayed on Corning Code 7059 plates preheated to 650° C. The effect of dilution and base coating 12 on emissivity is shown in the following table:
______________________________________ Bottom BottomTop Coating 14 Coating Coatingml In/Sn Soln. ml EtOAc Absent Aii of Ex. 1______________________________________100% 5 0 .19 .1080% 4 1 .19 .1160% 3 2 .21 .1040% 2 3 .28 .1320% 1 4 .43 .19______________________________________
Thus the amount of the expensive indium salt required can be reduced to about 40% of initial concentration without sacrifice of optical characteristics.
In Example 4 above, it was found that the use of tin doped indium oxide for top coating 14 provided a reasonably low emissivity when diluted, so that it is clear that a very low percentage of indium salts are used to form the coating material. However the emissivity of the top coating 14 was substantially improved when the bottom coating 12 of 10% antimony doped tin oxide was used, which coating is described in Example 1, i.e., the 0.1 solution.
EXAMPLE 5
Forming gas (92%N 2 -8%H 2 ) at 100 cc/min was bubbled into Fe(CO) 5 at room temperature, the resulting vapor stream diluted with forming gas at 1000 cc/min and then contacted with a glass substrate 10 preheated to 210° C. The initial deposit 12 was a highly reflective, metallic-appearing film while on continued reaction, a black smokey layer 14 formed over the base coating 12. Measurement of optical properties showed a solar absorptance of 0.93 and infra-red emissivity of 0.08.
(ESCA) analysis of the coatings revealed that the ratio of Fe/O was a minimum of 1.6:1 which is higher than magnetite (Fe 3 O 4 at 0.75:1). Scanning electron microscope (SCM) photos revealed a shiny bottom coating 12 and dull black rough top coating 14. It appears as if from this arrangement of composite coatings the absorbing property is exhibited by the rough surface quality of the top coating 14. The bottom coating 12 "looks through" the top coating 14 to suppress infrared emission.
EXAMPLE 6
Data, illustrating the effect of film thickness, in terms of volume and composition, on reflectivity as measured on a Gier-Dunkle DB-100 infrared reflectometer is displayed below.
Temp. --675° C.
Total spray volume adjusted to 70 cc with 1:4 HCl
Emissivity (ε)=1-(reflectivity)
From Ex 1Ai Sb/Sn=0.10
From Ex 1Aii Sb/Sn=0.01
______________________________________Spray Volume ml. Reflectivity (1 - ε)Sb/Sn .10 .01 .10 .01 Duplex______________________________________6.4 6.4 .277 .783 .8253 5 214 786 8093.6 3.6 212 745 775.5 5 263 778 8183.6 6.4 221 793 8217 5 309 780 8245 7 256 802 8265 5 257 786 8146.4 3.6 295 749 8005 3 267 713 7745 5 264 784 818______________________________________
The data for Example 6 shows an interaction between the absorber coating 12 (0.10 antimony dopant coating of Example 1) and reflectance (i.e. R=1-ε) of coating 14 (0.01 antimony dopant coating of Example 1) yielding a higher reflectivity (lower ε) at a given film thickness than the 0.01 antimony dopant coating of Example 1 alone. This would be economically advantageous since the absorber coating 12 thickness must be a minimum value to function efficiently. It would at the same time minimize the thickness of enhancing coating 14 clearly reducing film thickness thus reducing the materials requirements and not only reduce cost but in this case increase the effective reflectivity of the solar absorber illustrated in the drawing of FIG. 1. FIG. 2 illustrates a plot of the data of Example 6, of film thickness of 0.10 antimony dopant of Example 1 Ai; (absorber 12) vs. 0.01 antimony dopant of Example 1 Aii; (reflector 14) with R reflectivity as a dependent variable. For the data of Example 6, the following expression has been found to describe the relation of film thickness to reflectivity R.
R=544.0+19.5[A]+72.0[B]-3.06[A][B]-4.359[A] 2 with the square of correlation coefficient equal to 0.99.
A and B are the volumes of 0.10 and 0.01 antimony doped tin chloride solutions from Example 1Ai and 1Aii respectively.
The data points from the above calculation show a maximum (M) for the expression at 0.825 where indicated. The area within FIG. 16 indicates acceptable reflectivity for various combinations of film thickness measured in terms of volume. (See Table I below.) Lines 760 . . . 820 show the scale for the values of reflectivity (R×1000) selected in the drawing. The center point C illustrates the repeatable error for a group of readings.
Coating thickness is measured approximately in terms of spray volume. Table I shows the approximate relation of the coating thickness in Angstrom units versus spray volume in CC. on an enclosed heated one inch square.
TABLE I______________________________________Spray Vol. CC. Thickness A______________________________________3.0 17503.6 21005.0 28006.4 3750______________________________________
From the above table it is clear that reducing the spray volume by more than half does not cause a corresponding linear reduction in coating thickness. If thickness requirements can be reduced by improvements in the coating composition the total material requirements can be significantly reduced.
For example, in Example 3 above, the emissivity of the coating illustrated in Example 1, namely the 0.01 solution antimony-doped tin oxide was improved by the use of fluorine in the coating thereby significantly reducing both materials cost and volume requirements.
EXAMPLE 7
______________________________________Reflectivity ml. 49% HF/10 ml.R. Base Solution______________________________________.852 .32.888 .58.893 .82.894 .82.896 1.12.892 1.52.888 2.00.885 2.52______________________________________ Base solution 9.5 ml (1.40 gm SnCl.sub.4 . 5H.sub.2 O/ml)? 0.5 ml acetylacetone (H.sub.2 O + HF) = 4.0 ml.
FIG. 3 illustrates a comparison of an F2 composition for coating 14 which is adapted to act as an emissivity suppressor over an absorber (See F-2 in Ex. 7) with the theoretical minimum solar reflectance for a tin oxide system. The fluorine reduces the theoretical minimum by one half. The significance of FIG. 3 is that for thicker coatings (see Table I), the fluorine system acts as an antireflection coating in the solar region and as an infrared reflector thus suppressing emissions.
See FIG. 4 for the relation between a single coating (F-2) and a composite coating of the 0.10 film of Ex. 1Ai and F-2 above. It is clear that the composite coating reduces materials requirements, i.e., volume of solution for the same infrared reflectance. That is to say emissivity is suppressed in the infrared to a higher degree using less material.
In Example 5 it was shown that the composite coating can be used to produce both the heat mirror type coatings as illustrated in Examples 1-4 and also the tandem absorber reflector coating wherein the reflector "looks through" the absorber to suppress infrared radiation. In Example 6 it was shown that film thickness can be reduced while still maintaining high absorptance and low emissivity, and in Example 7 other materials such as fluorine, also described in Example 3 could be used to enhance the desired emissivity characteristic and reduce materials requirements as well as surprisingly reduce solar reflectance. It should also be appreciated from the foregoing that iron compositions could be combined with the coatings described to take advantage of their relatively low cost and availability.
While there have been described what are at present to be considered the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and it is intended in the appended claims to cover all such changes and modifications as fall within the true scope and spirit of the invention. | There has been provided composite coatings for solar absorber surfaces wherein solar radiation impinges on one surface of the absorber and which absorber is adapted to transfer energy so received from the impinging solar radiation in the form of sensible heat to a working fluid in contact with a delivery surface therewith comprising: a smooth surface absorber substrate having a first coating of metal oxides deposited on the smooth layer which oxides are selected from the group, consisting essentially of tin, antimony, indium and iron, and a second coating of metal oxides deposited on the first coating selected from the aforementioned group for said first layer; said first and second coatings disposed so as to exhibit a relatively high absorption characteristic α of at least 0.85 in the solar wavelength range, and a relatively low emissivity characteristic ε of less than 0.2 within the wavelength range of the infrared greater than about 2 micrometers. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to and the benefit of Korean Patent Application No. 10-2007-0068140 filed in the Korean Intellectual Property Office on Jul. 6, 2007, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a turbo charge system of an engine. More particularly, the present invention relates to a turbo charge system of an engine that minimizes energy loss of exhaust gas by mounting a crossover pipe that connects exhaust manifolds respectively mounted to cylinder heads at both sides of the engine, and the crossover pipe is formed as a double pipe structure.
(b) Description of the Related Art
Generally, an engine must take in as much air mixture as the exhaust gas amount, but it can actually take in only 80% of the exhaust gas amount. The amount of power an engine produces is proportional to the amount of airflow, and the number of valves may be increased or the diameter of the valves may be enlarged in order to increase the air intake amount. In addition, air may be forcibly blown in by a turbo charger in order to increase air intake amount.
Generally, a turbo charge system increases the air intake amount input to an intake manifold by using a turbo charger connected to the intake manifold and an exhaust manifold. More concretely, in a case in which a turbine of the turbo charger is forcibly rotated by exhaust gas having passed through the exhaust manifold, a compressor connected to the turbine rotates and forcibly blows air into the intake manifold. According to the turbo charge system, the high temperature and pressure exhaust gas passes through the turbine and its temperature and pressure are lowered. Therefore, energy of the exhaust gas is transmitted to the turbine and the turbine is rotated. Hence, if the temperature and pressure of the exhaust gas blown into a turbine housing is increased, the turbo charger will have higher efficiency.
According to a conventional turbo charge system for a multi-cylinder-head engine, an intake manifold and an exhaust manifold are mounted at respective sides of each cylinder head, and the exhaust manifolds are respectively connected to first and second turbo chargers. In addition, the first and second turbo chargers are respectively connected to intake manifolds mounted at each cylinder head. Therefore, when exhaust gas is blown into the first and second turbo chargers from the exhaust manifolds, turbines of the first and second turbo chargers rotate. In this case, a compressor connected to each turbine is rotated by rotation of the turbines and forcibly blows air into the intake manifolds. In addition, the exhaust manifolds are connected to each other by a crossover pipe. Therefore, when the engine is operated at a high speed or a high load condition, both the first and second turbo chargers are operated. On the contrary, when the engine is operated at a low speed or a low load condition, the exhaust gas exhausted from one exhaust manifold is gathered at the other exhaust manifold through the crossover pipe, and the gathered exhaust gas rotates the turbine of one turbo charger of the first and second turbo chargers. Thus, efficiency of the turbo charger is improved.
However, since the crossover pipe is mounted at the exterior of the cylinder head according to the conventional turbo charge system, noise may occur and the outward appearance of the cylinder head may be poor. In addition, since the crossover pipe is tightly bent and a length thereof is long, exhaust pressure loss may occur.
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
The present invention has been made in an effort to provide a turbo charge system of an engine having advantages of improved exhaust efficiency, reduced noise, and exclusion of an insulator as a consequence of mounting a crossover pipe connecting a pair of exhaust manifolds mounted at respective sides of a cylinder head in the cylinder head.
In addition, the present invention provides a turbo charge system of an engine having further advantages of preventing a cylinder head from receiving heat damage by forming the crossover pipe as a double pipe structure.
A turbo charge system of an engine according to an exemplary embodiment of the present invention may include a pair of exhaust manifolds respectively mounted to cylinder heads at both sides of the engine; a pair of turbo chargers respectively connected to the pair of exhaust manifolds and increasing intake air amount by using energy of exhaust gas; and a crossover pipe connecting the pair of exhaust manifolds with each other, wherein a crossover pipe is mounted in each cylinder head.
The crossover pipe may be formed as a double pipe structure that includes an inner pipe and an outer pipe.
The inner pipe may be disposed apart from the outer pipe by a predetermined distance.
Both ends of the inner pipe may be fixed by expansion rings that are formed at an interior surface of the outer pipe.
One end of the outer pipe may be integrally formed with a gasket.
The inner pipe may be formed as a bellows structure.
At least one air hole may be formed at the outer pipe.
A turbo charge system of an engine according to another exemplary embodiment of the present invention may include a pair of exhaust manifolds respectively mounted to cylinder heads at both sides of the engine; a turbo charger connected to at least one of the pair of exhaust manifolds and increasing intake air amount by using energy of exhaust gas; and a crossover pipe mounted in each cylinder head and connecting the pair of exhaust manifolds with each other, wherein the crossover pipe is formed as a double pipe structure that includes an inner pipe and an outer pipe.
The inner pipe may be disposed apart from the outer pipe by a predetermined distance.
Both ends of the inner pipe may be fixed by expansion rings that are formed at an interior surface of the outer pipe.
One end of the outer pipe may be integrally formed with a gasket.
The inner pipe may be formed as a bellows structure.
At least one air hole may be formed at the outer pipe.
The above features and advantages of the present invention will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated in and form a part of this specification, and the following Detailed Description of the Invention, which together serve to explain by way of example the principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated the accompanying drawings which are given hereinbelow by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1 is a front view of a turbo charge system of an engine according to an exemplary embodiment of the present invention.
FIG. 2 is a schematic diagram of a crossover pipe mounted in a turbo charge system of an engine according to an exemplary embodiment of the present invention.
FIG. 3 is a cross-sectional view of FIG. 2 taken along the line III-III.
FIG. 4 is an enlarged view of the “A” section of the crossover pipe shown in FIG. 3 .
FIG. 5 is an enlarged view of the “B” section of the crossover pipe shown in FIG. 3 .
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention.
The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Hereinafter reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. While the invention will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention to those exemplary embodiments. On the contrary, the invention is intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
FIG. 1 is a front view of a turbo charge system of an engine according to an exemplary embodiment of the present invention.
As shown in FIG. 1 , a turbo charge system according to an exemplary embodiment of the present invention is mounted to an engine. The engine includes cylinder heads 10 and a cylinder block 15 .
The engine is provided with intake manifolds 25 at an upper portion thereof and with exhaust manifolds 20 at both sides thereof. Each cylinder head 10 is provided with intake valves and intake cams in order to draw an air mixture into the intake manifold 25 , and is provided with exhaust valves and exhaust cams in order to discharge exhaust gas.
In addition, as shown in FIG. 2 , the exhaust manifolds 20 mounted at the sides of the cylinder heads 10 are connected with each other through a crossover pipe 30 , and a crossover pipe 30 is mounted in each cylinder head 10 .
Cylinders (not shown) are formed in the cylinder block 15 , and a piston (not shown) is mounted in each cylinder. The pistons move reciprocally by the explosive force of an air/fuel mixture. In addition, a crankshaft (not shown) that is rotated by the reciprocal motion of the pistons is mounted in the cylinder block 15 , and a connecting rod connects each piston with the crankshaft. A coolant pathway in which coolant flows is formed in the cylinder block 15 . In addition, first and second turbo chargers 50 and 55 are mounted at both sides of the engine and are respectively connected to a pair of exhaust manifolds 20 . Two turbo chargers 50 and 55 are used in the turbo charge system of the engine according to an exemplary embodiment of the present invention, but only one turbo charger may be used. In that case, one exhaust manifold 20 of the pair of exhaust manifolds 20 is connected to the turbo charger 50 and the exhaust gas is discharged to the turbo charger 50 from the one exhaust manifold 20 . In addition, the other exhaust manifold 20 discharges the exhaust gas to the one exhaust manifold 20 through the crossover pipe 30 .
The first and second turbo chargers 50 and 55 are respectively connected to the pair of exhaust manifolds 20 , and turbines of the first and second turbo chargers 50 and 55 are rotated by the exhaust gas discharged from the exhaust manifolds 20 . In addition, the first and second turbo chargers 50 and 55 are respectively connected to the pair of intake manifolds 25 , and forcibly blow air into the pair of intake manifolds 25 .
The turbo charge system of the engine according to an exemplary embodiment of the present invention may be 2-step turbo charge system which is selectable. That is, in a low speed condition or a low load condition, exhaust gas is discharged to one turbo charger 50 between the first and second turbo chargers 50 and 55 . On the contrary, in a high speed condition or a high load condition, the exhaust gas is discharged to both the first and second turbo chargers 50 and 55 .
Hereinafter, referring to FIG. 2 to FIG. 5 , a connection between the exhaust manifold and the crossover pipe in the turbo charge system of the engine according to an exemplary embodiment of the present invention will be described in detail.
FIG. 2 is a schematic diagram of a crossover pipe mounted in a turbo charge system of an engine according to an exemplary embodiment of the present invention, FIG. 3 is a cross-sectional view of FIG. 2 taken along the line III-III, FIG. 4 is an enlarged view of the “A” section of the crossover pipe shown in FIG. 3 , and FIG. 5 is an enlarged view of the “B” section of the crossover pipe shown in FIG. 3 .
As shown in FIG. 2 and FIG. 3 , the pair of exhaust manifolds 20 mounted at both sides of the engine are connected with each other through the crossover pipes 30 , and a crossover pipe 30 is mounted in each cylinder head 10 . Therefore, the length of each crossover pipe 30 may be shortened and exhaust loss may be reduced. In addition, appearance of the engine may be good.
The crossover pipe 30 is formed as a double pipe structure where an inner pipe 34 is mounted in an outer pipe 32 . Since the temperature of the exhaust gas is generally 750-800° C., durability of the cylinder head 10 is deteriorated by heat of the exhaust gas when the crossover pipe 30 is mounted in the cylinder head 10 . Therefore, the crossover pipe 30 is formed as the double pipe structure in order to prevent the cylinder head 10 from suffering from heat damage.
In addition, the inner pipe 34 is disposed apart from the outer pipe 32 by a predetermined distance in order to prevent the cylinder head 10 from suffering from the heat damage caused by the high temperature exhaust gas passing through the inner pipe 34 .
The inner pipe 34 is formed as a bellows structure 36 in order to not be broken by the heat of the exhaust gas. In addition, at least an air hole 44 is formed at the crossover pipe 30 in order to emit heat of the exhaust gas. Air holes 44 may be formed at upper and lower portions of the crossover pipe 30 , and are preferably located at corresponding positions.
As shown in FIG. 4 and FIG. 5 , both ends of the inner pipe 34 are fixed by expansion rings 38 and 40 extending inwards from an interior surface of the distal ends of the outer pipe 32 respectively to internal portions of the outer surface of the inner pipe. As shown in FIG. 5 , one distal end of the outer pipe 32 connected to one end of the exhaust manifold 20 is integrally formed with a gasket 42 thereon in order to prevent the exhaust gas coming from the exhaust manifold 20 from leaking in the outer pipe 32 through a gap between the outer pipe 32 and the inner pipe 34 . The outer pipe 32 and the gasket 42 may be made of the same material. In addition, the gasket 42 may be integrally formed with an distal end of the expansion ring 40 .
According to the present invention, the overall length of a crossover pipe may be shortened, and exhaust loss and noise may be reduced since a crossover pipe is mounted in a cylinder head. In addition, exhaust efficiency may be improved and appearance may be good since an insulator can be removed.
Further, a cylinder head may be prevented from suffering from heat damage since a crossover pipe is formed as a double pipe structure including an inner pipe and an outer pipe and the inner pipe is disposed apart from the outer pipe by a predetermined distance.
Since an inner pipe that directly contacts exhaust gas is formed as a bellows structure, the inner pipe may be prevented from being broken by heat of the exhaust gas
The forgoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiment were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that technical spirit and scope of the present invention be defined by the Claims appended hereto and their equivalents. | A turbo charge system of an engine minimizes energy loss of exhaust gas as a consequence of a crossover pipe that connects exhaust manifolds respectively mounted to cylinder heads at both sides of the engine with each other and that is mounted in each cylinder head, and the crossover pipe is formed as a double pipe structure. The turbo charge system of the engine may include a pair of exhaust manifolds respectively mounted to cylinder heads at both sides of the engine; a pair of turbo chargers connected respectively to the pair of exhaust manifolds and increasing intake air amount by using energy of exhaust gas; and a crossover pipe connecting the pair of exhaust manifolds with each other, wherein a crossover pipe is mounted in each cylinder head. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to a fence-like partition for an inside of a house, more particularly to such a partition having a gate, and specifically to an in-house gated partition or safety barrier that is height adjustable along the entire length of the partition.
BACKGROUND OF THE INVENTION
[0002] A gate for the inside of a house may be placed at the top of a staircase, at the bottom of a staircase, at the entry way to the kitchen, at the exits to a living room, or at some other location in the house to control access to and from certain areas of the house. Some gates are big. Other gates are small. However, families change. Children grow. Dogs have puppies. Thus, over time, different gates are purchased and some gates are stored in the garage, never to be used again.
SUMMARY OF THE INVENTION
[0003] A feature of the present invention is the provision in height adjustable barrier, of a lower barrier section having a lower set of lower vertically extending support members and an upper barrier section having an upper set of upper vertically extending support members, with each of the upper vertically extending support members aligned with and slideably engaging one of the lower vertically extending support members.
[0004] Another feature of the present invention is the provision in such a height adjustable barrier, of a gate in the lower and upper barrier sections.
[0005] Another feature of the present invention is the provision in a such a height adjustable barrier, of a release connection between at least one vertically extending support member and the lower vertically extending support member with which said at least one vertically extending support member is aligned, wherein said quick release connection fixes the lower barrier section relative to the upper barrier section such that the lower barrier section is not slideable relative to the upper barrier section until the quick release connection is released.
[0006] Another feature of the present invention is the provision in such a height adjustable barrier, of a gate lower barrier section having a lower set of lower vertically extending support members and a gate upper barrier section having a upper set of upper vertically extending support members, with each of the upper vertically extending support members of the gate upper barrier section aligned with and slideably engaging one of the lower vertically extending support members of the gate lower barrier section.
[0007] Another feature of the present invention is the provision in such a height adjustable barrier, of one of said lower and upper vertically extending support members including a tube and the other of said lower and upper vertically extending support members being slideable in said tube.
[0008] Another feature of the present invention is the provision in such a height adjustable barrier, of a pincher or pinch mechanism between at least one pair of the pairs of lower and upper vertically extending support members that are paired with each other such that the upper and lower barrier sections are slideable vertically relative to each other when the pincher is engaged and are not slideable vertically relative to each other when the pincher is disengaged.
[0009] Another feature of the present invention is the provision in such a height adjustable barrier, of a slippery sleeve between at least some of the pairs of upper and lower vertically extending support members to enhance slideability between the upper and lower barrier sections.
[0010] Another feature of the present invention is the provision in such a height adjustable barrier, of another lower barrier section and another upper barrier section, with said lower barrier sections being engaged to each other, and with said upper barrier sections being engaged to each other, such that the height adjustable barrier is extendable in length or lateral direction.
[0011] Another feature of the present invention is the provision in such a height adjustable barrier, of a lower horizontally extending support member engaging and spacing apart lower vertically extending support members, of an upper horizontally extending support member engaging and spacing apart upper vertically extending support members, and of a medial horizontally extending support member engaging one of the lower and upper barrier sections and engaging and spacing apart the vertically extending support members of such barrier section.
[0012] An advantage of the present invention is that the barrier is adjustable in height. The height adjustable barrier may be placed at a certain height pursuant to a particular place in the house, pursuant to a particular family having infants, small children or teenagers, or pursuant to other factors. Moreover, as children or dogs grow, a new gate need not be purchased.
[0013] Another advantage of the present invention is that the gate in the height adjustable barrier is adjustable in height along with, and at the same time as, all sections of the barrier or barriers.
[0014] Another advantage of the present invention is that the height adjustable barrier is also adjustable in length to reach between relatively narrow or relatively wide doorways or points of access.
[0015] Another advantage of the present invention is that the height adjustable barrier is quickly, readily and easily adjustable in height.
[0016] Another advantage of the present invention is that the height adjustable barrier is safe and sturdy whether the barrier is in a lowered position or a raised position. One feature contributing to this advantage is the relatively long or relatively elongated overlap between the upper and lower vertically extending support members when the barrier is in the raised position. Another feature contributing to this advantage is the provision of a sleeve between the upper and vertically extending support members that permits a true and tight fit between the upper and lower vertically extending support members while permitting an easy and relatively slippery sliding between the upper and lower vertically extending support members. Another feature contributing to this advantage is the medial horizontally extending support member disposed between the upper and lower horizontally extending support members.
[0017] Another advantage of the present invention is that the height adjustable barrier is relatively inexpensive to manufacture.
[0018] Another advantage of the present invention is that the height adjustable barrier may be set at an infinite number of heights. The vertically extending support members are slideable relative to each other and are thus incrementally adjustable relative to each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a perspective view of the present gated height adjustable barrier.
[0020] FIG. 2 is a perspective, partial view of the gated height adjustable barrier of FIG. 1 , showing raised and lowered positions of the upper barrier section.
[0021] FIG. 3 is a detail, side, partially section view of a quick release connection or pincher for one pair of vertically extending support members of the height adjustable barrier of FIG. 1 .
[0022] FIG. 4 is a perspective, detail view of an end portion of the gated height adjustable barrier of FIG. 1 engaging a track mounted on a door frame or frame of a point of access.
[0023] FIG. 5 is a detail, side, partially section view the end portion of FIG. 4 and shows how the barrier can engage relatively narrow points of access or relatively wide points of access.
[0024] FIG. 6 is a side, partial view of the gated height adjustable barrier of FIG. 1 that further includes a barrier extension having upper, lower, and medial horizontally extending support members and upper and lower vertically extending support members.
[0025] FIG. 7 is a detail, side, partially section view showing a slippery sleeve that permits easy sliding of the upper and lower vertically extending support members and that contributes to the stability of the upper and lower vertically extending support members relative to each other.
DESCRIPTION
[0026] FIG. 1 shows a gated height adjustable barrier 12 . Barrier 12 includes a lower barrier section 16 and an upper barrier section 18 . Barrier 12 includes a height direction, a length direction, and a width direction, with all such directions being normal to each of the other two directions.
[0027] Lower barrier section 16 includes a lower horizontally extending support member 20 . Member 20 is a metal tube, generally rectangular in section. Member 20 includes, at each of its end portions, a through hole 21 extending through member 20 in the width direction. As shown in FIG. 6 , member 20 can receive a pin connector 22 for engaging a height adjustable barrier 24 that does not include a gate. Member 20 further includes at and centered in each of its end faces, a threaded opening extending in the length direction for engaging a horizontally adjustable extension 25 .
[0028] Lower barrier section 16 further includes a set of lower vertically extending support members 26 engaged to, such as by welding, the lower horizontally extending support member 20 . Each of the lower vertically extending support members 26 engage therein an upper vertically extending support member 27 depending from the upper barrier section 18 .
[0029] Lower vertically extending support member 26 is tubular and includes an upper open end 28 , as shown in FIG. 7 . Two of the lower vertically extending support members 26 confront opposite sides of a swingable gate 30 . As shown in FIG. 1 , these two members 26 are indicated by reference numbers 32 , 34 and can be referred to as lower vertically extending base support members 32 , 34 . These base support members 32 , 34 are rectangular in section and are relatively large, and are about the size of the lower horizontally extending support member 20 . Two other of the lower vertically extending support members 26 are indicated by reference numbers 36 , 38 and can be referred to as lower vertically extending end support members 36 , 38 . End support members 36 , 38 are cylindrical in shape.
[0030] Lower barrier section 16 further includes a lower gate barrier section 40 having a lower horizontally extending gate support member 42 , and a set of lower vertically extending support members 26 , of which two are gate end support members 44 , 46 and of which the remaining four are inner cylindrical support members 48 . Support members 44 , 46 are generally square in section. Gate end support member 44 has a downwardly projecting tab 50 , shown in FIG. 6 , that confronts and makes contact with a side face of the lower horizontally extending support member 20 to stop the gate 30 from swinging fully through a plane of the barrier 12 . Gate end support member 46 is pivotally joined along a vertical axis at a lower end to horizontally extending support member 20 such that gate 30 swings on such vertical axis defined generally by gate end support member 46 .
[0031] Lower barrier section 16 further includes first, second and third medial horizontally extending support members 52 , 54 , 56 . First and second end members 52 , 54 are disposed at the ends of the lower barrier section 16 and third member 56 is disposed therebetween in the gate 30 . Support members 52 , 54 , 56 are disposed in line or on a straight line with each other. Each of the members 52 , 54 , 56 fixedly engages the upper ends or end portions of their respective lower vertically extending support members 26 and spaces such members 26 apart from each other such that members 26 remain parallel to each other. Members 52 , 54 , 56 take the shape of an inverted U in section and include bracing 58 , 60 , shown in FIG. 7 . Bracing 58 extends widthwise or from side face to side face of the members 52 , 54 , 56 . Bracing 60 extends lengthwise such as between bracing members 58 and between bracing 58 and a cylindrical receptor 62 that frictionally engages the upper end or upper end portion of lower vertically extending support member 26 . Members 52 , 54 , 56 are one-piece and integral with bracing 58 , bracing 60 and cylindrical receptors 62 .
[0032] Upper barrier section 18 includes first, second and third upper horizontally extending support members 64 , 66 , 68 . Members 64 , 66 , 68 are preferably aligned with each other in a straight line. Members 66 and 68 , tied together with extension 100 , are raised and lowered together when pinchers 86 are operated. Member 64 is raised and lowered independently of members 66 and 68 , regardless of whether latch 102 is engaged or disengaged.
[0033] Each of the upper vertically extending support members 27 is now described more particularly. Members 64 and 66 are disposed on outer ends of the barrier 12 and have outer cylindrical tubes 70 , 72 depending therefrom. Tubes 70 , 72 slide vertically inside of respective tubes 36 , 38 of lower barrier section 16 . Members 64 , 66 further have inner gate confronting tubes 74 , 76 depending therefrom. Tubes 74 , 76 are rectangular in section and slide vertically inside of respective tubes 32 , 34 of lower barrier section 16 . Member 68 have outer tubes 78 , 80 depending therefrom. Tubes 78 , 80 are generally square in section and slide vertically inside of respective tubes 44 and 46 . Member 68 further includes a set of four cylindrical tubes 82 depending therefrom. Tubes 82 slide vertically inside of tubes 48 . Tubes 78 , 80 , 82 can be referred to as gate vertically extending support members.
[0034] In other words, upper barrier section 18 includes a set of upper vertically extending support members 70 , 72 , 74 , 76 , 78 , 80 and 82 engaged to, such as by welding, their respective upper horizontally extending support members 64 , 66 , 68 . These upper vertically extending support members 70 , 72 , 74 , 76 , 78 , 80 and 82 are generally referred to as upper vertically extending support members 27 . The lower vertically extending support members 32 , 34 , 36 , 38 , 44 , 46 and 48 are generally referred to as lower vertically extending support members 26 .
[0035] Each of the upper and lower vertically extending support members 26 , 27 is a shaft in the nature of a tube or rod and is preferably a tube to minimize barrier weight. Upper vertically extending support members 27 slideably engage their respective lower vertically extending support members 26 so as to slideably engage the lower barrier section 16 to the upper barrier section 18 .
[0036] As shown in FIG. 7 , some of the upper open ends 28 of lower vertically extending support members 26 include an insert or sleeve 84 for engaging its respective upper vertically extending support members 27 . Sleeve 84 may include a relatively wide annular integral portion that rests upon the top of vertically extending support member 26 and a relatively narrow annular integral portion that extends in an elongated fashion below the relatively wide annular integral portion. Sleeve 84 spaces the paired lower and upper vertically extending support members 26 and 27 from each other such that the members 26 and 27 do not rub against one another. The vertically running opening in sleeve 84 has a surface that is manufactured or coated or that has a composition to be slippery such that members 26 and 27 are readily slideable relative to each other. Sleeve 84 is fixed within the open end 28 in a rigid or friction fit fashion such that sleeve 84 does not pop or ride out of open end 28 when the members 26 and 27 slide relative to each other.
[0037] Sleeve 84 is not utilized where a pincher 86 is used. As shown in FIG. 3 , pincher 86 includes a cylindrical first portion 88 that frictionally fits upon an upper end of one of the lower vertically extending support members 26 , namely, tubes 36 , 72 and one of the tubes 48 . Each of these vertically extending support members 36 , 72 , 48 extends a short way beyond the upper face of its respective medial horizontal support member 52 , 54 , 56 to permit such cylindrical portion 88 to be capped upon its upper end. At this point, it should be noted that the upper ends of the other lower vertically extending support members 26 terminate within the medial horizontal support member 52 , 54 , 56 , as shown in FIG. 7 . Cylindrical first portion 88 includes, in the nature of sleeve 84 , a vertically extending through opening that receives upper vertically extending support member 27 in a slippery sliding fashion.
[0038] Pincher 86 further has a threaded second portion 90 extending upwardly and integrally from cylindrical first portion 88 . Pincher 86 further includes a slotted tapered third portion 92 extending upwardly and integrally from threaded second portion 90 . Third portion 92 includes a set of four vertically extending slots 94 disposed at ninety degrees relative to each other. Pincher 86 further includes a pinching collar 96 rotatably mounted on vertically extending support member 27 . Pinching collar 96 has inner threads that engaged threaded second portion 90 and further includes a tapered inner surface that circumferentially engages tapered slotted portion 92 to reduce the width of slots 94 and thus the diameter of portion 92 such that portion 92 circumferentially grabs and frictionally holds member 27 relative to member 26 . The tapered features of pinching collar 96 and third portion 92 permit a fixing of members 26 and 27 with each other to a relatively greater or lesser degree in an incremental manner such that, for example, the height of the upper barrier section 18 can be temporarily set with a medium degree of drag produced by slotted portion 92 . Then, when the desired height is ascertained, the pinching collar 96 is fully turned such that slotted portion 92 produces a relatively high amount of drag to a point where the upper and lower barrier sections 16 , 18 are locked relative to each other.
[0039] Pincher 86 controls the length of insertion of member 27 into member 26 . Pincher 86 and its portions 88 , 90 , 92 include a through opening that functions in the nature of sleeve 84 . Pinching collar 96 and second portion 90 include interacting helical threads. Slot 94 can be referred to as a generally axially extending slot. Slot 94 permits width-wise expansion and contraction or radial expansion and contraction or diametrical expansion and contraction of the slotted portion 92 . Portion 92 is contracted when pinching collar 96 is threaded onto portion 90 . The inner through opening of pinching collar 96 is tapered so as to decrease in radius from a lower portion to an upper portion. With such a tapering, portion 92 is incrementally contracted or squeezed to as to incrementally apply greater and greater pressure upon upper vertically extending support member 27 when pinching collar 96 is screwed onto portion 90 . When pinching collar 96 is screwed off portion 90 , portion 92 incrementally expands and the engagement between portion 92 and vertically extending support member 27 is loosened such that the lower and upper vertically extending support members 26 and 27 slide relatively freely relative to each other. Slot 94 is open ended and runs out of an upper end of portion 92 .
[0040] Barrier 12 includes the gate 30 . Gate 30 includes a portion of the lower barrier section 16 and a portion of the upper barrier section 18 . More specifically, gate 30 includes the lower horizontally extending gate support member 42 , the upper horizontally extending support member 68 , gate end vertically extending support member 44 , gate end vertically extending support member 46 , vertically extending square gate tubes 78 and 80 that slide vertically in support members 44 and 46 respectively, medial horizontally extending support member 56 , four gate inner cylindrical and tubular support members 48 , four inner cylindrical tubes 82 sliding vertically in the support members 48 , and one or more pinchers 86 .
[0041] Gate 30 is pivotally engaged via the lower horizontally extending gate support member 42 to the lower horizontally extending support member 20 at a location 98 near the juncture of the support member 42 and gate end support member 46 . Gate 30 is pivotally engaged via upper horizontally extending support member 68 to an extension or strip 100 protruding from upper horizontally extending support member 66 . Swinging of the gate 30 extends to one side of the barrier 12 only. Swinging of the gate 30 to the other side is prevented by tab 50 that confronts a side of the lower horizontally extending support member 20 . In other words, the barrier 12 generally defines a plane and the gate 30 swings out of the plane to one side of the plane, and back into the plane, but not to the other side of the plane, since the gate 30 is restricted by the tab 50 hitting the side of the lower horizontally extending support member 20 .
[0042] Gate 30 further includes a latch 102 having generally four parts. Latch 102 includes a body 104 that is rigidly secured to upper horizontally extending support member 68 , vertically extending square tube 78 and its adjacent cylindrical tube 82 . Latch 102 further includes a lock 106 that slidingly engages upper horizontally support member 68 . Latch 102 further includes a handle arm 108 that pivotally engages the body 104 . The latch 102 further includes a generally U-shaped piece 110 that captures both sides of a portion of vertically extending support member 74 and a portion of horizontally extending support member 64 . U-shaped piece 110 slidingly engages the body 104 and is drawn to and away from members 64 , 74 by handle arm 108 that includes tabs that ride in vertically oriented slots formed in U-shaped piece 110 . It can be appreciated that U-shaped piece 110 has a length slightly longer on one side than an opposite side such that U-shaped piece 110 , even when fully drawn in by handle arm 108 , remains in a confronting position with one side of member 64 and one side of member 74 (which sides are coplanar) such that U-shaped piece 110 performs an upper confronting function in the manner (and on the same side of the barrier 12 ) that tab 50 performs a lower confronting function. Lock 106 via an upper ridge normally prevents a swinging upwardly of handle arm 108 . To operate handle arm 108 , lock 106 is slid away from body 104 and then the handle arm 108 can be swung upwardly.
[0043] As shown in FIGS. 4 and 5 , barrier 12 further includes a guide track or slide 112 and a rider or upper extension 114 extending from both of the ends 115 of horizontally extending support members 64 , 66 . Rider or extension 114 includes a threaded shaft 116 having rigidly affixed thereto a rider head or slide head or disk 118 such that turning of the head 118 turns the shaft 116 . Shaft 116 is threadingly engaged with an opening in the ends 115 of the horizontally extending support members 64 , 66 such that the head 118 can be set at greater or lesser distances from the ends of the horizontally extending support members 64 , 66 . Shaft 116 turns on an axis common with the axis of the horizontally extending support members 64 , 66 . Rider 114 further includes a relatively large hand manipulated locking nut 120 that threadingly engages the shaft 116 . Nut 120 , when turned and one face is set against end 115 , or when turned and the other face is set against track 112 , rigidly fixes shaft 116 from being turned and thereby sets the head 118 at a given distance from end 115 .
[0044] Track 112 is mounted on a wall or other vertical surface 122 via one or more pin connectors 124 . Track 112 is generally C-shaped and includes a slot 126 for reception of the shaft 116 . Slot 126 has a width greater than or equal to the diameter of the shaft 116 and less than the diameter of the head 118 so as to retain the head 118 in the track or guide member 112 and, at the same time, permit smooth vertical sliding of the head 118 in the track 112 . Track 112 and slot 126 have an open upper end 128 .
[0045] As shown in FIG. 1 , barrier 12 further includes the horizontally adjustable lower extension 25 . This can also be referred to as a pressurizing extension 25 . Extension 25 includes the structure shown in FIG. 5 . In other words, extension 25 includes the threaded shaft 116 having rigidly affixed thereto a head or disk 118 such that turning of the head 118 turns the shaft 116 . Shaft 116 is threadingly engaged with an opening in ends of the lower horizontally extending support member 20 such that the head 118 can be set at greater or lesser distances from the ends of the lower horizontally extending support member 20 . Shaft 116 turns on an axis common with the axis of the lower horizontally extending support member 25 . Extension 25 further includes the relatively large hand manipulated locking nut 120 that threadingly engages the shaft 116 . Nut 120 is first turned against the inner face of head 118 such that the head 118 can be turned or screwed inwardly or outwardly. By turning head 118 such that the length of extension 25 is extended, lower horizontal support member 20 can be pressure mounted between two walls 112 when both heads 118 are turned into and against both walls 112 . The relatively large roughened circumference of nut 120 allows for a relatively easy fixing, under pressure, of the heads 118 and hence the lower portion of the barrier 12 between two vertical surfaces 112 . Then, if desired, the nut 120 can be turned back the other way to fix the other face of the nut 120 against the end of the lower horizontal support member 20 to lock the shaft 116 or fix the shaft 116 from turning.
[0046] It should be noted that, if desired, the lower barrier section 16 may be engaged to vertical surface 122 with a guide track or slide 112 and a rider or upper extension 114 .
[0047] The barrier extension 24 is shown in FIG. 6 . This barrier extension 24 includes a lower horizontally extending support member 132 , a medial horizontally extending support member 134 , and a set of three vertically extending support members or vertically running cylindrical tubes 136 fixed between the members 132 , 134 . Barrier extension 24 further includes an upper horizontally extending support member 138 with a set of three vertically extending support members or vertically running cylindrical tubes 140 depending therefrom. Tubes 140 slide vertically in tubes 136 . A pincher 86 is engaged between the pair of middle tubes 136 , 140 and the other two pairs of tubes 136 , 140 include the sleeve 84 . Barrier extension 24 further includes a lower receptor 142 and an upper receptor 144 extending respectively from the lower and upper horizontally support members 132 , 138 . Receptors 142 , 144 are C-shaped and engage the upper and side faces of end portions of the lower and upper horizontally extending support members 20 and 64 (or 66 ) of main barrier 12 with pin connectors 22 .
[0048] FIG. 6 further shows that barrier 12 can include upper and lower pressurizing extensions 25 on each of the upper and lower horizontally extending support members 138 , 132 (or on members 64 and 20 , or on members 66 and 20 ). That is, the track or guide member 112 need not be included such that barrier 12 utilizes pressurizing extensions 25 at four locations, with two pressurizing extensions 25 disposed on each of the sides (or ends) of the barrier 12 , where one each side (or end) each of a lower and upper pressurizing extension 25 is used. This is in contrast to the preferred embodiment, where a pair of pressurizing extensions 25 are used for a lower engagement of the lower barrier section 16 to a pair of vertical surfaces 122 and where a pair of track 112 and rider 114 combinations are used for an upper engagement of the upper barrier section 18 to a pair of vertical surfaces 122 .
[0049] In operation, tracks 112 are fixed to opposing vertical surfaces 122 . Then shafts 116 are turned in or out to increase or decrease an effective length (or width) of barrier 12 such that the respective heads 118 can drop into respective open ends 128 . Then locking nuts 120 are fixed to either the track 112 or end 115 to fix the shafts 116 at the appropriate lengths. Then, or prior to the time of adjusting the length of shafts 116 , the lower horizontal extensions 25 are turned out so as to fix the lower barrier section 16 securely in place between the opposing vertical surfaces 122 . Then, as shown in FIG. 2 , the pinchers 86 are loosened to permit sliding of the upper barrier section 18 relative to the lower barrier section 16 . During this sliding, the heads 18 ride up and down in the tracks 112 . At the desired height, the pinchers 86 are tightened. The pinchers 86 are tightened when the upper barrier section 18 is in a raised position, such as shown in FIG. 2 in phantom, when the upper barrier section 18 is in a lowered position, such as shown in FIG. 2 , and when the upper barrier section 18 is at any position between the shown raised and lowered positions. Gate 30 is openable and closeable when the upper barrier section 18 is in any raised, lowered, or in-between position.
[0050] It should be noted that gate 30 includes a latching end or support member 44 that swings in an arc. Upper vertically extending support member 32 of the upper barrier section 18 opposes the latching end 44 . The height adjustable barrier 12 includes an operating configuration, such as between vertical surfaces 122 , and a storable configuration such as where the barrier 12 is laid flat and is not engaged between any two vertical surfaces 122 . The latching end 44 is spaced a given distance from the upper vertically extending support member 32 in each of the operating and storable configurations such that the gate 30 is not a pressure gate. A pressure gate may be a pressure gate where a barrier section, with which a gate barrier section swings into and out of engagement, has vertically extending support members slightly off parallel with vertically extending support members of the gate barrier section. Here, upper horizontally extending support member 64 , medial horizontally extending support member 52 , lower horizontally extending support member 20 , vertically extending support members 32 , 36 , 70 , and 74 can be referred to an end barrier section. Such end barrier section has vertically extending support members 26 , 27 that remain at all times parallel to the vertically extending support members 26 , 27 of the gate barrier section 30 whether the barrier section 12 is fixed between two vertical surfaces 122 in an operating configuration or whether the barrier section 12 is in a stored configuration and laid flat.
[0051] Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalents of the claims are intended to be embraced therein. | A barrier or partition for the inside of a house having upper and lower barrier sections that are adjustable relative to each other such that the barrier as a whole is adjustable in height. The upper and lower barrier sections have paired vertically extending support members that slide relative to each other. At least one pair of vertically extending support members have a pincher or pincher mechanism that squeezes upon one of the vertically extending support members to fix the vertically extending support members in a nonsliding fashion relative to each other. The barrier includes a gate that also includes upper and lower sections and paired vertically extending support members that slide relative to each other. Further upper and lower sections, with or without gates, may be laterally attached or detached to increase or decrease a length of the barrier. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
None.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mirror in a motor vehicle, in particular a vanity mirror, at the periphery of which is arranged at least one preferably reflective OLED without a spacing.
2. Related Art
Mirrors are sufficiently known from the prior art and are nowadays equipped with additional features. By way of example, DE 101 40 689 A1 discloses a vehicle mirror comprising a mirror plate and an organic light-emitting diode display (OLED) formed from two substrates and an OLED layer, the mirror plate directly forming one of the substrates of the OLED display. In the case of said mirror it is possible to project information into the reflective surface. A further rear-view mirror with a display unit is disclosed in DE 103 25 845 A1. Furthermore, it is known from the prior art for mirrors to have illuminations. The illumination of said mirrors is based, in accordance with the prior art, on a construction composed of a housing, incandescent bulb, bulb holder, wiring, reflector and diffusing screen. These constructions have a height of several millimeters. What is more, the diffusing screen must be configured in removable fashion in order to enable a defective incandescent bulb to be exchanged. These disadvantages restrict the possible uses of such illuminations as vehicle mirror illumination, in particular as make-up mirror illumination.
Therefore, the present invention was based on the object of providing a mirror which does not have the disadvantages of the prior art.
SUMMARY OF THE INVENTION
The object is achieved by means of a mirror in a motor vehicle, in particular a vanity mirror, at the periphery of which is arranged at least one, preferably reflective, OLED without a spacing.
For the person skilled in the art, it could not be expected that the mirror according to the invention is illuminated very well. The OLEDs at the periphery of the mirror are embodied so flat that the OLEDs and the mirror can be arranged in a frame. What is more, the OLED light does not dazzle the observer. Due to the extremely high lifetime of the OLED, reversible incorporation thereof for purposes of service can be dispensed with.
A mirror within the meaning of the invention is any reflective surface which reflects a highest possible proportion, preferably about 100%, of impinging light. According to the invention, at least one OLED is arranged at the periphery of said mirror. Consequently, the OLED in the preferred embodiment is not part of said reflective surface but rather borders the reflective surface at least partly.
According to the invention, the illumination unit according to the invention has an OLED (Organic Light Emitting Diode). OLEDs constitute an electronic component which generally has a plurality of thin organic current-conducting layers. The OLEDs may be constructed so as to have a thickness of less than 3 mm, preferably less than 1.4 mm and particularly preferably <1 mm. Preferably, but by no means necessarily, the OLEDs have a transmission of >70%, and particularly preferably >75% in the non-driven state. OLEDs generally have a carrier layer, for example, glass, to which a luminous coating is applied, and a covering layer, for example, likewise glass. The carrier layer preferably has a reflective layer, which reflects the light emitted by the diodes and which acts as a mirror in the non-driven state of the diodes. The OLEDs emit a bright, diffuse light that does not dazzle. OLEDs are distinguished by a very fast response speed. By attachment of an appropriate filter, a white light-emitting OLED can be modified to emit light in any desired color. This is advantageous, for example for reading light. However, a color effect of the OLEDs can also be obtained without filters. Furthermore, OLEDs are very lightweight and have an extremely high durability, such that, by way of example, the weight of a vehicle and the replacement intervals of the illumination unit can be reduced. In general, replacement can be completely obviated on account of the long lifetime. Comparatively large-area illuminations can also be realized due to the comparatively low weight of the OLEDs.
The OLED is preferably, but not of necessity, a reflective OLED. One embodiment of the present invention has the advantage that the reflective OLED looks like a mirror in the non-driven (i.e., non-energized) state. A surface having a homogeneous reflective appearance thereby arises in association with the mirror.
The mirror may have an OLED at least at one part of the periphery of said mirror. The mirror furthermore may have a respective OLED at two opposite parts of the periphery of said mirror. The mirror and the OLED can be arranged in one plane, in particular the area that faces the user lying in one plane, although other arrangements are contemplated.
In another exemplary embodiment, the OLED is arranged in curved fashion. In yet another variation, the OLED is arranged in a manner angled with respect to the mirror. This latter embodiment has the advantage, in particular that light emitted by the OLED does not dazzle the observer, and that the OLED in the turned-off state enables three-dimensional observation for the observer.
The mirror and the OLED may be arranged in a mirror cassette. One disclosed embodiment of the present invention enables a simple mounting, in particular. For the case where the mirror is not intended to have any illumination, a larger mirror can be used in this disclosed embodiment of the present invention, without changing the frame, which reduces the equipment diversity, for example in motor vehicle mounting.
The mirror according to the invention is suitable in particular for arrangement at vehicle interior trim parts. Therefore, a further subject matter of the present invention is a vehicle interior trim part having the mirror according to the invention.
The vehicle interior trim part is preferably a sun visor or a headrest, in each of which the mirror according to the invention is arranged.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained below with reference to FIGS. 1 to 3 . These explanations are merely by way of example and do not restrict the general concept of the invention. The explanations apply equally to both subject matters of the invention.
FIG. 1 shows the mirror according to the invention in plan view;
FIG. 2 shows the mirror according to the invention in accordance with FIG. 1 in a side view; and
FIG. 3 shows a further embodiment of the mirror in accordance with FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a mirror 1 according to one embodiment of the invention. In the present case, the mirror 1 is configured in rectangular fashion and has a respective OLED 3 at the right-hand and the left-hand surface of the periphery 2 of said mirror. The OLED is a reflective OLED, which acts like a mirror in the non-driven (i.e., non-energized) state, such that the surfaces 1 and 3 in the non-driven state of the OLEDs act like a large, essentially homogeneous mirror surface. In the driven state, the reflective OLEDs 3 function as luminaires and, in the case of a vanity mirror, illuminate for example the observer's face.
FIG. 2 illustrates a side view of the mirror in accordance with FIG. 1 . This view reveals that the mirror 1 comprises a substrate 4 , a glass substrate in the present case, which has a reflective surface 6 at its rear side. The OLEDs 3 are identified by the reference symbol 5 and have a reflective surface 7 at their rear side. The OLED 3 comprises a covering plate, a substrate and also an OLED layer with electrodes, which are identified jointly by the reference symbol 5 . The reflective layers 6 , 7 reflect impinging light up to about 100%. In the non-driven state, the surfaces 1 , 3 act as a continuous mirror surface.
FIG. 3 illustrates a further embodiment of the mirror in accordance with FIGS. 1 and 2 . The mirror in accordance with FIG. 3 essentially corresponds to the mirror in accordance with FIGS. 1 and 2 , in the present case the OLEDs 3 being arranged in angular fashion with respect to the mirror 1 . This embodiment of the present invention has the advantage that the observer of the mirror is illuminated better, that said observer is dazzled to a lesser extent by the light from the OLEDs, and that the OLEDs in the turned-off state generate a three-dimensional mirror image. The person skilled in the art recognizes that it is also possible for a plurality of OLEDs to be arranged alongside one another which, relative to the paper plane, can have a different angle and/or a different curvature.
The foregoing invention has been described in accordance with the relevant legal standards, thus the description is exemplary rather than limiting in nature. Variations and modifications to the disclosed embodiment may become apparent to those skilled in the art and fall within the scope of the invention. Accordingly the scope of legal protection afforded this invention can only be determined by studying the following claims.
LIST OF REFERENCE SYMBOLS
1 Mirror
2 Periphery
3 OLED
4 Substrate, glass
5 OLED
6 , 7 Reflective surfaces | The invention relates to a mirror in a motor vehicle, in particular a make-up lighted or/vanity style mirror. At least one preferably reflective organic light-emitting diode display abuts the periphery of said mirror. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a part incorporating system for incorporating a part or parts in a base material in, for instance, a vehicle assembly line, and more particularly to such an incorporating system in which a part or parts to be incorporated in a base material is positioned with respect to the base material by the use of a visual sensor like a television camera.
2. Description of the Prior Art
Advances in automation have been made in vehicle frame welding lines and vehicle frame coating lines. However, assembly line automation has been considered to be difficult due to difficulties in positioning parts with respect to base materials in which the part is to be incorporated, e.g., in a vehicle frame. More specifically, if the part is not positioned in place with respect to the base material when the part is incorporated in the base material with a fastener such as a bolt and nut by the use of an automatic incorporating system, the bolt and nut cannot be satisfactorily applied.
In order to overcome such problems, it has been proposed in, for instance, Japanese Unexamined Utility Model Publication No. 58-169987 to adjust the position of the parts with respect to the base material by the use of a TV camera. In this system, when the position of the base material in which the parts are incorporated in the base material fluctuates or the position of the part with respect to the base material fluctuates, the part incorporating position in which the parts are to be incorporated in the base material is detected by the TV camera and the position of the part with respect to the base material is adjusted.
However, this system, has the problem that the detection of the part incorporating position can become incorrect due to displacement of the TV camera and or the influence of external disturbing light, and in such cases the position of the part cannot be correctly adjusted with respect to the base material.
SUMMARY OF THE INVENTION
In view of the foregoing observations and description, the primary object of the present invention is to provide an improved part incorporating system in which the position of the part can be correctly adjusted with respect to the base material in which the part is to be incorporated with less influence from any displacement of the visual sensor (e.g., a TV camera) and/or external disturbing light.
In accordance with the present invention, there is provided a part incorporating system for incorporating a part in a base material comprising a plurality of visual sensors which are disposed in predetermined positions at a detecting station provided immediately upstream of an incorporating station and respectively detect the positions of a plurality of reference points provided in the base material when the base material is supplied to the detecting station, a plurality of second visual sensors which are disposed in predetermined positions at the incorporating station and respectively detect the positions of the reference points provided in the base material when the base material is supplied to the incorporating station, an incorporating unit which is provided at the incorporating station to support the part so that the position of the part can be adjusted and is provided with a fastening device for incorporating the part in the base material, and a control means which compares the values of the distances between the reference points as calculated on the basis of the detected positions of the respective reference points detected by the first visual sensors at the detecting station with the regular values of the corresponding distances to determine whether any of the first visual sensors is in an abnormal condition depending on whether the differences therebetween are within predetermined permissible values, compares the values of the distances between the reference points as calculated on the basis of the detected positions of the respective reference points detected by the first visual sensors determined to be in the normal condition with the values of the corresponding distances as calculated on the basis of the detected positions of the respective reference points detected by the second visual sensors at the incorporating station to calculate the incorporating position of the part in the base material on the basis of the detected positions of the reference points detected by the second visual sensors when the difference therebetween is within a predetermined value with respect to all the values of the distances, and on the basis of, when the difference therebetween is larger than the predetermined value with respect to any of the values of the distances, the detected position of the reference point providing the value of the distance closer to the regular value of the corresponding distance with respect to the reference point related to the value of the distances the difference between which is larger than the predetermined value, and adjusts the position of the part supported on the incorporating unit according to the result of the calculation of the incorporating position of the part.
With this arrangement, the part incorporating position is basically calculated on the basis of the detected positions of the reference point detected by the second visual sensors and when the values of the distances between the reference points as calculated on the basis of the positions of the reference points detected by the second visual sensors differ from those as calculated on the basis of the positions of the reference points detected by the first visual sensors by a predetermined value, the part incorporating position is calculated on the basis of the detected positions of the reference points which provides the values of the distances between the reference points closer to the regular values. Accordingly, even if one or more of the second visual sensors comes to be unable to correctly detect the position of the reference point, the correct position of the reference point can be obtained and the part incorporating position can be correctly calculated. Further, when one or more of the first visual sensors comes to be unable to correctly detect the position of the reference point, the part incorporating position is calculated on the basis of the detected positions of the reference points detected by the second visual sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view showing a part incorporating system in accordance with an embodiment of the present invention,
FIG. 2 is an enlarged side view showing the incorporating station of the system,
FIG. 3 is a view for illustrating the principle of the present invention, and
FIG. 4 is a flow chart illustrating the operation of the system of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Now an embodiment of the present invention in which the present invention is applied to incorporate an engine and suspensions in a vehicle frame in a vehicle assembly line will be described in detail with reference to FIGS. 1 to 4.
As shown in FIGS. 1 and 2, a vehicle assembly line is provided with an incorporating station 2 for incorporating an engine-front suspension assembly B and a rear suspension assembly C in a vehicle frame A, and a detecting station 1 disposed immediately upstream of the incorporating station 2. The vehicle frame A is conveyed from the detecting station 1 to the incorporating station 2 supported on a hanger 4 suspended from an overhead conveyor rail 3 and is stopped at the incorporating station 2.
At the incorporating station 2, there are disposed a first incorporating unit 10 for incorporating the engine-front suspension assembly B in the vehicle frame A and a second incorporating unit 20 for incorporating the rear suspension assembly C in the vehicle frame A. Further, the incorporating section 2 is provided with a first supplier 30 for delivering the engine-front suspension assembly B to the first incorporating unit 10 and a second supplier 40 for delivering the rear suspension assembly C to the second incorporating unit 20. The first and second suppliers 30 and 40 are of substantially the same structure. The first supplier 30 comprises a supply conveyor 32 for conveying the engine-front suspension assembly B placed on a table 31 in a direction perpendicular to the conveying direction of the vehicle frame A along the rail 3, a transfer mechanism 33 which is disposed at the downstream end of the supply conveyor 32 to transfer the assembly B on the table 31 to the first incorporating unit 10 together with the table 31 and to recover the empty table 31, a lift mechanism 34 which is movable between an upper position and a lower position and lowers the empty table 31 delivered from the transfer mechanism 33 to the lower position, and a return conveyor 35 which is provided to extend in parallel to the supply conveyor 32 therebelow and conveys in the direction opposite to the supply conveyor 32 the empty table 31 delivered from the lift mechanism 34 in the lower position thereof. Similarly, the second supplier 40 comprises a supply conveyor 42 for conveying the rear suspension assembly C placed on a table 41 in a direction perpendicular to the conveying direction of the vehicle frame A along the rail 3, a transfer mechanism 43 which is disposed at the downstream end of the supply conveyor 42 to transfer the assembly C on the table 41 to the second incorporating unit 20 together with the table 41 and to recover the empty table 41, a lift mechanism 44 which is movable between an upper position and a lower position and lowers the empty table 41 delivered from the transfer mechanism 43 to the lower position, and a return conveyor 45 which is provided to extend in parallel to the supply conveyor 42 therebelow and conveys in the direction opposite to the supply conveyor 42 the empty table 41 delivered from the lift mechanism 44 in the lower position thereof.
The first and second incorporating units 10 and 20 are of substantially the same structure. The first incorporating unit 10 comprises a base 11 fixed to a floor 5, a lift cylinder 12 vertically mounted on the base 11, a support table 13 mounted on the top of the piston rod of the lift cylinder 12, and first to third movable tables 14, 15 and 16 placed one on another in this order on the support table 13. The first or the lower most movable table 14 has slide blocks 14a which are fixed to the lower face thereof and are slidably engaged with guide rails 13a fixed to the upper face of the support table 13 to extend in a direction parallel to the conveying direction of the vehicle frame A (y-y direction), whereby the first movable table 14 is slidable in the y-y direction. The intermediate or the second movable table 15 has guide rails 15a which are fixed to the lower face thereof to extend in a direction x-x perpendicular to the conveying direction of the vehicle frame A and are slidably engaged with slide blocks 14b fixed on the upper face of the first movable table 14, whereby the second movable table 15 is slidable in the x-x direction. The third or the uppermost movable table 16 is supported on a rotational shaft 16a for rotation with respect to the second movable table 15. The first movable table 14 is slid in the y-y direction with respect to the support table 13 driven by a first motor (not shown), the second movable table 15 is slid in the x-x direction with respect to the first movable table 14 driven by a second motor (not shown), and the third movable table 16 is rotated with respect to the second movable table 15 driven by a third motor (not shown). Further, the third movable table 16 is provided with a fastening device 17 for incorporating the engine-front suspension assembly B in the vehicle frame A. Similarly, the second incorporating unit 20 comprises a base 21 fixed to the floor 5, a lift cylinder 22 vertically mounted on the base 21, a support table 23 mounted on the top of the piston rod of the lift cylinder 22, and first to third movable tables 24, 25 and 26 placed one on another in this order on the support table 23. The first or the lower most movable table 24 has slide blocks 24a which are fixed to the lower face thereof and are slidably engaged with guide rails 23a fixed to the upper face of the support table 23 to extend in a direction parallel to the conveying direction of the vehicle frame A (y-y direction), whereby the first movable table 24 is slidable in the y-y direction. The intermediate or the second movable table 25 has guide rails 25a which are fixed to the lower face thereof to extend in a direction x-x perpendicular to the conveying direction of the vehicle frame A and are slidably engaged with slide blocks 24b fixed on the upper face of the first movable table 24, whereby the second movable table 25 is slidable in the x-x direction. The third or the uppermost movable table 26 is supported on a rotational shaft 26a for rotation with respect to the second movable table 25. The first movable table 24 is slid in the y-y direction with respect to the support table 23 driven by a first motor (not shown), the second movable table 25 is slid in the x-x direction with respect to the first movable table 24 driven by a second motor (not shown), and the third movable table 26 is rotated with respect to the second movable table 25 driven by a third motor (not shown). Further, the third movable table 26 is provided with a fastening device 27 for incorporating the rear suspension assembly C in the vehicle frame A.
The detecting station 1 is provided with four first TV cameras I to IV disposed in predetermined positions on the floor 5, and the incorporating station 2 is provided with four second TV cameras I' to IV' disposed in predetermined positions on the floor 5. The four first TV cameras I to IV disposed at the detecting station 1 are positioned to respectively view the four corners of the under side of the vehicle frame A conveyed in the detecting station 1 and stopped there and to detect the positions of reference points (reference holes) a to d (See FIG. 3) provided in predetermined positions of the under side of the vehicle frame A at the four corners. The four second TV cameras I' to IV' disposed at the incorporating station 2 are positioned to respectively view the four corners of the under side of the vehicle frame A conveyed in the incorporating station 2 and stopped there, and to detect the positions of the reference points a to d.
Detecting signals S1 to S4 and S1' to S4' representing the positions of the reference points a to d detected by the first TV cameras I to IV and the second TV cameras I' to IV' are input into a control unit 50. The control unit 50 receives these signals and outputs actuating signals t1 to t3 and t1' to t3' to the first to third motors of the first and second incorporating units 10 and 20. Thereafter, the control unit 50 actuates the fastening devices 17 and 27 of the third movable tables 16 and 26 of the first and second incorporating units 10 and 20.
The operation of the control unit for adjusting the position of the assemblies B and C with respect to the vehicle frame A will be described, hereinbelow.
As shown in FIG. 3, the first TV cameras I to IV are disposed at the detecting station 1 so that the centers O 1 to O 4 of the image taking surfaces thereof are positioned at the respective corners of a rectangle, one pair of opposed sides of which extend in parallel to the conveying direction of the vehicle frame A (the y-y direction) spaced from each other in the direction perpendicular to the conveying direction of the vehicle frame A (the x-x direction) by a distance Lx, and the other pair of opposed sides of which extend in perpendicular to the conveying direction of the vehicle frame A (the y-y direction) spaced from each other in the direction parallel to the conveying direction of the vehicle frame A (the x-x direction) by a distance Ly. Further, four coordinate systems (x 1 , y 1 ), (x 2 , y 2 ), (x 3 , y 3 ) and (x 4 , y 4 ) respectively having their origins on the centers O 1 to O 4 are defined. There is further defined a coordinate system (X , Y) having its origin on the center O 1 , its X-axis on the line passing through the center O 1 in perpendicular to the conveying direction of the ehicle frame A and its Y-axis on the line passing through the center O 1 in parallel to the conveying direction of the vehicle frame A, the positive side of Y-axis being on the upstream side of X-axis with respect to the conveying direction of the vehicle frame A. Similarly, the second TV cameras I' to IV' are disposed at the incorporating station 2 so that the centers O 1 ' to O 4 ' of the image taking surfaces thereof are positioned at the respective corners of a rectangle one pair of opposed sides of which extend in parallel to the conveying direction of the vehicle frame A (the y-y direction) spaced from each other in the direction perpendicular to the conveying direction of the vehicle frame A (the x-x direction) by a distance Lx', and the other pair of opposed sides of which extend in perpendicular to the conveying direction of the vehicle frame A (the y-y direction) spaced from each other in the direction parallel to the conveying direction of the vehicle frame A (the x-x direction) by a distance Ly'. Further, four coordinate systems (x 1 ', y 1 '), (x 2 ', y 2 '), (x 3 ', y 3 ') and (x 4 ', y 4 ') respectively having their origins on the centers O 1 ' to O 4 ' are defined. There is further defined a coordinate system (X', Y') having its origin on the center O 1 ', its X'-axis on the line passing through the center O 1 ' in perpendicular to the conveying direction of the vehicle frame A and its Y'-axis on the line passing through the center O 1 ' in parallel to the conveying direction of the vehicle frame A, the positive side of Y'-axis being on the upstream side of X'-axis with respect to the conveying direction of the vehicle frame A.
The reference points a to d on the under side of the vehicle frame A are disposed on the respective corners of a rectangle to correspond to the TV cameras I to IV or I' to IV'. The distance L 1 to L 6 between the reference points a to d are set shown in table 1 with the distances Lx, Ly, Lx' and Ly' being Lx=Lx'=1000 mm and Ly=Ly'=3000 mm.
TABLE 1
L 1 =1000 mm (±1 mm)
L 2 =3000 mm (±3 mm)
L 3 =3162 mm (±6 mm)
L 4 =3162 mm (±6 mm)
L 5 =3000 mm (±3 mm)
L 6 =1000 mm (±1 mm)
When the vehicle frame A is stopped at the detecting station 1, the first TV cameras I to IV detect the respective reference points a to d (step S1 in FIG. 4). For example, it is assumed that the coordinates of the reference points a to d on the corresponding coordinate systems (x 1 , y 1 ) to (x 4 , y 4 ) are as follows.
point a: (xa, ya)=(10.0, 50.0)
point b: (xb, yb)=(9.5, 49.5)
point c: (xc, yc)=(10.0, 52.0)
point d : (xd, yd)=(10.5 , 51.5)
To the control unit 50 are input the coordinates of the reference points a to d as the signals S1 to S4, and the control unit 50 converts the coordinates of the reference points to d on the coordinate systems (x 1 , y 1 ) to (x 4 , y 4 ) into the coordinates of the coordinate system (X , Y), thereby obtaining the following values.
point a: (Xa, Ya)=(10.0, 50.0)
point b: (Xb, Yb)=(1009.5, 49.5)
point c: (Xc, Yc)=(10.0, 3052.0)
point d: (Xd, Yd)=(1010.5, 3051.5)
The control unit 50 calculates the distances l 1 to l 6 between the reference points a to d from the coordinates of the points a to d, and compares the obtained values with the regular values L 1 to L 6 . (Steps S2 and S3) The obtained values of the distances l 1 to l 6 are as shown in table 2, and the difference from the regular values L 1 to L 6 are shown in the brackets in the table 2.
TABLE 2
l 1 =999.5 (-0.5)
l 2 =3002.0 (+2.0)
l 3 =3164.5 (+2.5)
l 4 =3163.8 (+1.8)
l 5 =3002.0 (+2.0)
l 6 =1000.5 (+0.5)
In this particular example, since the differences between the calculated values l 1 to l 6 of the distances between the points a to d and the regular values L 1 to L 6 of the same are all within the tolerances shown in the brackets in table 1, the control unit 50 determines that all the first TV cameras I to IV at the detecting station 1 correctly detect the corresponding reference points a to d (step S4), and then delivers the coordinates of the reference points a to d on the coordinate system (X , Y) to the incorporating station 2. (step S5) On the other hand, when one or more of the calculated values l 1 to l 6 is outside of the tolerance, the control unit 50 determines the reference point corresponding to the calculated value which is outside of the tolerance. (step S6) Then the TV camera detecting the reference point is determined to be in abnormal condition and the other TV cameras are determined to be in normal condition. The control unit 50 delivers the coordinates of the reference points detected by the TV cameras in the normal condition to the incorporating station 2. Irrespective of whether all the first TV cameras are in the normal condition, the incorporating positions of the assemblies B and C on the vehicle frame A are calculated on the basis of the positions (the coordinates) of the reference points, and then the motors of the first and second incorporating units 10 and 20 are operated to bring the assemblies B and C into the calculated mounting positions. (a primary position adjustment) (step S7)
After detection of the positions of the reference points a to d is completed at the detecting station 1, the vehicle frame A is conveyed to the incorporating station 2, and the positions of the reference points a to d are detected by the second TV cameras I' to IV' at the incorporating section 2. For example, it is assumed that the coordinates of the reference points a to d on the corresponding coordinate systems (x 1 ', y 1 ') to (x 4 ', y 4 ') are as follows.
point a: (xa', ya')=(13.5 ,52.0)
point b: (xb', yb')=(10.0,51.5)
point c: (xc', yc')=(10.5, 54.0)
point d: (xd', yd')=(11.0, 53.5)
The control unit 50 converts the coordinates of the reference points a to d on the coordinate systems (x 1 ', y 1 ') to (x 4 ', y 4 ') into the coordinates of the coordinate system (X', Y'), thereby obtaining the following values. (step S8)
point a: (Xa', Ya')=(13.5, 52.0)
point b: (Xb', Yb')=(1010.0, 51.5)
point c: (Xc, Yc)=(10.5, 3054.0)
point d: (Xd, Yd)=(1011.0, 3053.5)
The control unit 50 calculates the distances l 1 ' to l 6 ' between the reference points a to d by way of the coordinates of the points a to d, and compares the obtained values with those by way of the coordinates of the points a to d detected in the detecting station 1 and with the regular values L 1 to L 6 . (step S9) The obtained values of the distances l 1 ' to l 6 ' are as shown in table 3, and the difference from the regular values L 1 to L 6 are shown in the brackets (), and the difference from the value of the distances l 1 to l 6 are shown in the brackets [ ].
TABLE 3
l 1 '=996.5 (-3.5) [3.0]
l 2 '=3002.0 (+2.0) [0]
l 3 '=3164.5 (+2.5) [0]
l 4 '=3162.5 (+0.5) [1.3]
l 5 '=3002.0 (+2.0) [0]
l 6 '=1000.5 (+0.5) [0]
Then, the values of the distances l 1 ' to l 6 ' obtained in the incorporating station 2 are compared with those obtained in the detecting station 1, and it is determined whether the differences therebetween are smaller than a predetermined value. (step S 10 and step Sll) In this case, when one or more of the first TV cameras has been determined to be in an abnormal condition in the step S7, the value or values calculated on the basis of the point or points detected by the first TV camera(s) determined to be in an abnormal condition is omitted, and the other values are compared with those obtained in the incorporating station 2.
When the differences between the values subjected to the comparison are all smaller than the predetermined value, the control unit 50 determines the coordinates of the reference points a to d on the coordinate system (X', Y') in step S13. In this case, it is considered that all the second TV cameras I' to IV' correctly detect the positions of the respective reference points a to b, and accordingly the positions of the reference points a to d detected by the second TV cameras I' to IV' are adopted as the final coordinates, and the incorporating positions of the assemblies B and C are calculated on the basis of the positions of the reference points.
When the incorporating positions of the assemblies B and C determined in the step S13 on the basis of the positions of the reference points detected in the incorporating station 2 deviate from those determined in the step S7 on the basis of the positions of the reference points detected in the detecting station 1, the former incorporating positions are adopted and the first and second incorporating units 10 and 20 are operated to correct the positions of the assemblies B and C.
In the example shown in table 3, the differences between the values l 1 and l 1 ' and between the values l 4 and l 4 ' are not smaller than the predetermined value as shown in the brackets [ ]. Accordingly it is considered that the positions of the reference points a (related to both the values of l 1 and l 4 ) detected in the detecting station 1 and the incorporating station 2 differ from each other by a predetermined amount. This suggests the possibility that there is something wrong with the second TV camera I' detecting the point a at the incorporating station 1. Accordingly, if the incorporating positions are calculated on the basis of the position of the reference point a detected by the TV camera I', an incorrect incorporating position may be obtained. Therefore, the control unit 50 adopts one of the combination of the values (l 1 , l 2 , l 4 ) detected in the detecting station 1 and the combination of the values (l 1 ', l 2 ', l 4 ') (related to the reference point a) which is generally closer to the regular values (Ll, L2, L3), that is, the former combination in this particular example, and calculates the coordinates of the reference point a at the incorporating station 2 (Xa', Ya') on the basis of said one of the combination and the coordinates of the reference points b, c and d obtained in the incorporating station 2, (Xb', Yb'), (Xc', Yc') and (Xd', Yd'). This calculation is made as follows.
(Xb'-Xa').sup.2 +(Yb'-Ya').sup.2 =l.sub.1.sup.2 (1)
(Xc'-Xa').sup.2 +(Yc'-Ya').sup.2 =l.sub.2.sup.2 (2)
(Xd'-Xa').sup.2 +(Yd'-Ya').sup.2 =l.sub.4.sup.2 (3)
In the case of the above example, Xb'=1010.0, Yb'=51.5, Xc'=10.5, Yc'=3054.0 Xd'=1011.0, Yd'=3053.5, l 1 =999.5 l 2 =3002.0, l 4 =3163.8. By substituting these values for the corresponding values in formulae (1), (2) and (3), the coordinates of the point a at the incorporating station 2, (Xa', Ya'), can be obtained.
However, depending on the detecting error of the first TV cameras I to IV and the second TV cameras I' to IV', the above formulae cannot be true. In such a case, two of the three formulae in which out of the values l 1 , l 2 and l 3 , two values the deviations from the regular values (L 1 , L 2 , L 3 ) of which are smaller than that of the other one are included are used and the linear coordinates of the point a are calculated through the two formulae. In this example, the deviations from the regular values L 1 and L 4 of the values l 1 and l 2 are smaller than that of the value l 2 . Accordingly, the linear coordinates of the point a are calculated through the formulae (1) and (3). The two coordinates of the point a thus obtained are substituted for the corresponding values in formula (2) to obtain two values of l 2 . One of the two coordinates of the point a which provides the value of l.sub. 2 closer to the regular value L 2 may be adopted as the coordinates of the point a at the incorporating station 2, (Xa', Ya').
Thus, whether one or more of the second TV cameras I' to IV' at the incorporating station 2 is in abnormal condition is detected through a comparison of the distances l 1 ' to l 2 ' between the reference points a to d as calculated on the basis of the positions of the reference points a to d detected by the second TV cameras I' to IV' and the distances l 1 to l 6 between the reference points a to d as calculated on the basis of the positions of the reference points a to d, and the position of the reference point at the incorporating station 2 detected by the second TV camera which is determined to be in abnormal condition is calculated on the basis of the distances between the reference points selected through a comparison with the regular values of the distances between the reference points, whereby the positions of all the reference points a to d at the incorporating station 2 can be determined with a high accuracy. Then the incorporating positions of the assemblies B and C are calculated on the basis of the positions of the reference points a to d thus determined, and the incorporating units 10 and 20 are operated to bring the assemblies into the respective incorporating positions. Accordingly, the assemblies B and C can be incorporated in the vehicle frame A correctly by the fastening devices 17 and 27 even if one or more of the TV cameras is in an abnormal condition,
Since the positions of the reference points a to d are detected at the detecting station 1 before the vehicle frame A is fed to the incorporating station 2, the range over which the reference points a to d must be searched for may be relatively narrow, and accordingly, detection of the reference points a to d at the incorporating station 2 can be performed with a high accuracy and in a relatively short time, whereby the time for which the vehicle frame A is stopped at the incorporating station is shortened. | A part incorporating system includes a plurality of visual sensors at a detecting station immediately upstream of an incorporating station and respectively detect the positions of reference points in the base material when the base material is supplied to the detecting station, a plurality of second visual sensors at the incorporating station and respectively detect the positions of the reference points when the base material is supplied to the incorporating station, an incorporating unit at the incorporating station to support the part so that the position of the part can be adjusted and which has a fastening device for incorporating the part in the base material, and a control means which calculates the position in which the part is to be incorporated in the base material and controls the incorporating unit to adjust the position of the part. The part incorporating position is basically calculated based on the positions of the referenc epoints detected by the second visual sensors, and when the values of the distances between the reference points detected by the second visual sensors differ from those detected by the first visual sensors by a predetermined value, then the part incorporating position is calculated on the basis of the detected positions of the reference points which provides the values of the distances between the reference points closer to the regular values. | 8 |
BACKGROUND OF THE INVENTION
[0001] Extreme ultraviolet (EUV) lithography, which is based upon exposure with the portion of the electromagnetic spectrum having a wavelength of 10-15 nanometers, can be used to print features with smaller critical dimension (CD) than other more conventional techniques, such as those utilizing deep ultraviolet (DUV) radiation. For example, an EUV scanner may use 4 imaging mirrors and a Numerical Aperture (NA) of 0.10 to achieve a CD of 50-70 nm with a depth of focus (DOF) of about 1.00 micrometer (um). Alternatively, an EUV scanner may use 6 imaging mirrors and a NA of 0.25 to print a CD of 20-30 nm although the DOF will be reduced to about 0.17 um.
[0002] Masking and reflection of EUV radiation brings about a unique set of challenges generally not encountered with DUV radiation. For example, a mask for DUV lithography is transmissive, and layers of materials such as chrome and quartz may be used to effectively mask or transmit, respectively, DUV radiation. Thus, a desired pattern on a DUV mask may be defined by selectively removing an opaque layer, such as chrome, to uncover portions of an underlying transparent substrate, such as quartz. However, virtually all condensed materials absorb at the EUV wavelength, so a mask for EUV lithography is reflective, and the desired pattern on an EUV mask is defined by selectively removing portions of an absorber layer (“EUV mask absorber”) to uncover portions of an underlying mirror coated on a substrate, the mirror, or reflective multilayer (“ML”), generally comprising a number of alternating layers of materials having dissimilar EUV reflectivity constants.
[0003] One of the challenges in EUV lithography involves minimizing geometric defects, or the effects thereof, which may be present in a substrate surface underlying the reflective multilayer. Conventional polishing techniques employed upon conventional EUV mask blank substrate materials such as titanium silicate glasses, for example, the glass sold under the trade name ULE™ by Corning Corporation, or glass ceramics, for example, the glass sold under the trade name Zerodur™ by Scott Glass Technologies, generally are capable of reducing defects significantly. Subsequent to application of such polishing techniques, bumps, pits, and scratches sized between about 2 nanometers and about 100 nanometers may still be defined within the substrate surface.
[0004] Absent efficient techniques for substantially eliminating such remaining surface defects, their effects may be minimized by adding extra layers to the reflective multilayer. Adding layers to the multilayer, however, complicates the lithography process and increases susceptibility to other masking problems. There is a need for an efficient solution to mitigate the effects of defects defined within EUV substrate surfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The present invention is illustrated by way of example and is not limited in the figures of the accompanying drawings, in which like references indicate similar elements. Features shown in the drawings are not intended to be drawn to scale, nor are they intended to be shown in precise positional relationship.
[0006] [0006]FIG. 1A depicts a cross sectional view of a substrate layer having defects.
[0007] [0007]FIG. 1B depicts a close-up cross sectional view of the substrate layer of FIG. 1A.
[0008] [0008]FIG. 2A depicts a cross sectional view of an embodiment of the present invention wherein a polyimide layer is formed adjacent a substrate layer having defects.
[0009] [0009]FIG. 2B depicts a close-up cross sectional view of the structures of FIG. 2A.
[0010] [0010]FIG. 3 depicts polyamid-type polyimide precursors which may be thermally cured to form a polyimide layer adjacent a substrate layer in accordance with various embodiments of the present invention.
[0011] [0011]FIG. 4 depicts a cross sectional view of various aspects of the present invention wherein a polyimide layer is formed between a substrate layer and a reflective multilayer.
[0012] [0012]FIG. 5A depicts a cross sectional view of an EUV mask blank in accordance with one embodiment of the present invention.
[0013] [0013]FIG. 5B depicts a cross sectional view of an EUV mask blank in accordance with one embodiment of the present invention.
[0014] [0014]FIG. 6 depicts a flow chart illustrating forming an EUV mask in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
[0015] In the following detailed description of embodiments of the invention, reference is made to the accompanying drawings in which like references indicate similar elements. The illustrative embodiments described herein are disclosed in sufficient detail to enable those skilled in the art to practice the invention. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the invention is defined only by the appended claims.
[0016] Referring to FIG. 1A, a cross sectional view of a substrate layer ( 100 ) is depicted. The substrate layer ( 100 ), preferably comprising a material with a low defect level and a smooth surface such as glass or glass-ceramic with a low coefficient of thermal expansion (“CTE”), preferably is used as the starting material for an EUV mask. In certain cases, the substrate ( 100 ) may be formed from silicon despite the relatively large CTE of silicon, so long as heat can be removed uniformly and effectively during exposure. Other suitable substrate layer ( 100 ) materials include but are not limited to titanium silicate glasses, such as that sold under the trade name ULE™ by Corning, and glass ceramics such as that sold under the trade name Zerodur™ by Schott Glass Technologies. The substrate layer preferably has a thickness of about {fraction (1/4)} inch. To minimize defect geometries defined within the surface of the substrate layer, the substrate may be polished to result in a smoothed surface which generally still defines both positive defects, which protrude away from the substrate layer, and negative defects, which are defined into the surface—such as scratches or pits. Referring to FIG. 1A, the depicted substrate layer ( 100 ) has a multitude of positive defects ( 110 , 112 , 114 ) and negative defects ( 102 , 104 , 106 , 108 ). While the depicted defects are substantially uniform in geometry, actual cases will have varying geometries, as would be apparent to one skilled in the art.
[0017] Referring to FIG. 1B, a close-up cross sectional view of a portion of the structure of FIG. 1A is depicted to show a positive defect ( 112 ) adjacent a negative defect ( 106 ), the protrusion height ( 116 ) of the positive defect, and the depth ( 118 ) of the negative defect ( 106 ) as defined into the substrate. Subsequent to a smoothing treatment to minimize the geometries of such defects, such as a chemical mechanical polishing treatment with a conventional small particle size slurry, each of the protrusion height ( 116 ) and depth ( 118 ) preferably are less than about 100 nanometers.
[0018] Referring to FIG. 2A, a structure similar to that of FIG. 1A is depicted, with the exception that a polyimide layer ( 120 ) is formed upon the substrate layer ( 100 ) to substantially infill each of the negative defects ( 102 , 104 , 106 , 108 ), cover each of the positive defects ( 110 , 112 , 114 ), and provide a substantially uniform and planar surface upon which other structures may be positioned. FIG. 2B is a close up view to illustrate the infilling of a negative defect ( 106 ) and the covering of a positive defect ( 112 ) by the polyimide layer ( 120 ), which in the illustrated embodiment has a thickness ( 122 ) slightly greater than the protrusion height ( 116 ) of the positive defect ( 112 ) subsequent to curing. To provide a substantially uniform and smooth surface subsequent to curing, it is preferable that the polyimide layer ( 120 ) have a thickness after curing at least sufficient to cover the highest protruding positive defect.
[0019] To form a very thin polyimide layer ( 102 ) having a thickness in the range of about 100 nanometers, in accordance with the protrusion height ( 116 ) in the aforementioned scenario, polyimide material may be deposited in a relatively low viscosity form using conventional spin-on or spin coating techniques. Suitable polyimide precursors for very thin layer spin on are available from suppliers such as Hitachi Dupont Microsystems, Asahi Kafei, and Toray Dow Corning. For example, the suitable product sold under the trade name P12613™ by Hitachi Dupont Microsystems is available in a N-Methyl-2-Pyrrolidone (“NMP”) solvent system at about 6% solids with a viscosity of between about 130 and about 160 centistokes (“cSt”). Both polyamid and pre-imidized polyimide precursor types are suitable for use in this invention. Polyimide precursors preferably are deposited using conventional spin-on or spin coating techniques, followed by thermal curing under a vacuum to form a thin polyimide layer subsequent to curing. Polyamid type precursors preferably are cured to form a polyimide layer by heating to a temperature between about 250 and 400 degrees Celsius, while pre-imidized precursors may be cured at lower temperatures, such as around 200 degrees Celsius, as would be apparent to one skilled in the art. Polyimide precursors may be categorized as non-photosensitive or photosensitive. Referring to FIG. 3, the structures of three polyamid type precursors are depicted: a polyamic acid ( 300 ) non-photosensitive precursor, along with polyamic ester ( 302 ) and polyamic salt ( 304 ) photosensitive precursors. As noted above, each of these types of precursors may be spin-on deposited and then thermally cured ( 306 ), preferably at a temperature between about 250 and 400 degrees Celsius under a vacuum, to form a polyamide ( 308 ) layer subsequent to curing. Applied vacuum conditions are preferred during curing to prevent outgassing and improve interdigitation with the substrate surface.
[0020] Heating profiles during thermal cure ( 306 ) vary with the particular material at issue and desired film thickness, in accordance with published spin speed versus thickness curves available for various temperature profiles. For example, the supplier of the aforementioned P12613™ product discloses that a spin speed of about 5,000 RPM for about 30 seconds, followed by a soft bake at 90 degrees Celsius for 90 seconds, another soft bake at 150 degrees Celsius, ramping from 150 degrees Celsius to 350 degrees Celsius at about 4 degrees Celsius per minute, then a curing bake at 350 degrees Celsius for 30 minutes and subsequent cool down to ambient, results in a polyimide layer of about 150 nanometers thickness, with thinner layers available with longer spin times before curing.
[0021] Referring to FIG. 4, subsequent to curing the polyimide layer ( 120 ), a reflective multilayer may be formed adjacent the polyimide layer ( 120 ) using conventional techniques. The reflective multilayer ( 124 ) preferably comprises about 20-80 pairs of alternating layers of a high index of refraction material and a low index of refraction material. As would be apparent to one skilled in the art, a high index of refraction material includes elements with high atomic number which tend to scatter EUV light, and a low index of refraction material includes elements with low atomic number which tend to transmit EUV light. The choice of materials for the reflective multilayer ( 124 ) depends upon the illumination wavelength (“lambda”). To a first approximation, each layer has a thickness of about one quarter of lambda. More specifically, the thickness of the individual layers depends on the illumination wavelength, lambda, and the incidence angle of the illumination light. For EUV, the wavelength is about 13.4 nm and the incidence angle is about 5 degrees. The thicknesses of the alternating layers are tuned to maximize the constructive interference of the EUV light reflected at each interface and to minimize the overall absorption of the EUV light. The reflective multilayer ( 124 ) preferably can achieve about 60-75% reflectivity at the peak illumination wavelength. In one embodiment, the reflective multilayer ( 124 ) comprises about 40 pairs of alternating layers of a high index of refraction material and a low index of refraction material. For example, each high index of refraction layer may be formed from about 2.8 nanometer thick molybdenum while each low index of refraction material may be formed from about 4.2 nanometer thick silicon. In another embodiment, the reflective multilayer ( 124 ) may comprise alternating layers of molybdenum and beryllium or other known pairings of suitable materials. For example, about 70 pairs of molybdenum/beryllium bilayers, each of which has a thickness of about 5.8 nanometers, about 40% of the bilayer thickness being molybdenum and the remaining 60% of the bilayer thickness being beryllium, may be utilized as a reflective multilayer ( 124 ).
[0022] The reflective multilayer ( 124 ) preferably is formed over the substrate ( 100 ) using ion beam deposition or DC magnetron sputtering. The thickness uniformity preferably is better than 0.8% across the substrate ( 100 ). Ion beam deposition may result in less perturbation and fewer defects in the upper surface of the reflective multilayer ( 124 ) because the deposition conditions usually may be optimized to smooth over any defect on the substrate layer ( 100 ). DC magnetron sputtering may be more conformal, thus producing better thickness uniformity, but substrate ( 100 ) defect geometry tends to propagate up through the alternating layers to the upper surface of the reflective multilayer ( 124 ).
[0023] Referring to FIG. 5A, an EUV mask absorber layer ( 126 ) may be formed adjacent the reflective multilayer ( 124 ). The mask absorber layer ( 126 ) preferably comprises a material such as tantalum nitride, tantalum oxynitride, and/or chromium which etches controllably to enable subsequent formation of trenches having very tight geometric tolerances and provides sufficient EUV irradiation exposure modification when formed into a layer of sufficient thickness, the requisite thickness varying with the selected mask absorber materials. Preferably the mask absorber layer ( 126 ) has a thickness less than about 150 nanometers and is formed using conventional techniques such as physical or chemical vapor deposition, or plasma enhanced chemical vapor deposition.
[0024] The combination of a substrate layer ( 100 ), polyimide layer ( 120 ), reflective multilayer ( 124 ), and mask absorber layer ( 126 ) may be termed an EUV “mask blank” ( 50 ) which may be further processed to form an EUV mask.
[0025] Referring to FIG. 5B, a structure, or mask blank ( 52 ), similar to that of FIG. 5A is depicted, with the exception that in the structure of FIG. 5B a protective layer ( 128 ) is disposed between the reflective multilayer ( 124 ) and mask absorber layer ( 126 ). Such a protective layer ( 128 ) may be formed before formation of the mask absorber layer ( 126 ) to protect the reflective multilayer ( 124 ) from oxidation or etching chemistries utilized during subsequent patterning and repair treatments associated with the mask absorber layer. Suitable protective layer materials include but are not limited to silicon, preferably about 11 nanometers thick and deposited along with the other silicon layers of the preferred reflective multilayer ( 124 ), silicon dioxide or silicon oxynitride deposited using conventional techniques such as physical or chemical vapor deposition or plasma enhanced chemical vapor deposition at a thickness of about 40-60 nanometers to protect underlying multilayer ( 124 ) materials from focused ion beam repair, or ruthenium, deposited at a thickness between about 2 nanometers and about 6 nanometers using the techniques for forming the aforementioned reflective multilayer ( 124 ), or other conventional techniques such as physical or chemical vapor deposition, or plasma enhanced chemical vapor deposition. Copending U.S. patent applications entitled “High Performance EUV Mask” and “Double-Metal EUV Mask Absorber”, assigned to the same assignee as the present invention, further describe the use of such protective layer materials, along with the aforementioned mask absorber layer ( 126 ) materials. The term “protective layer” utilized herein is in reference to layers also known as “buffer layers” or “capping layers”.
[0026] Referring to FIG. 6, a method to form an EUV mask in accordance with the techniques described herein is depicted in flowchart fashion. As described above, subsequent to minimizing substrate surface defect geometry ( 600 ) utilizing techniques such as polishing, a layer of polyimide precursor material is deposited upon the substrate ( 602 ), preferably using spin-on techniques, subsequent to which a thermal curing treatment forms a cured polyimide layer ( 604 ) from the polyimide precursors. As noted above, the thermal curing treatment ( 604 ) preferably is conducted in a vacuum to prevent outgassing and improve interdigitation with the substrate surface. Subsequent to forming a cured polyimide layer ( 604 ), a reflective multilayer may be formed ( 606 ) adjacent the cured polyimide layer. Further, protective ( 608 ) and mask absorber ( 610 ) layers may be formed adjacent the reflective multilayer and protective layer, respectively.
[0027] Each of the structures of FIGS. 5A and 5B are improved by the substrate-defect-mitigating polyimide layer ( 120 ), which limits propagation of positive and negative defects to subsequently formed layers, and therefore enables a more uniform and precise EUV mask. Thus, a novel substrate defect mitigation solution is disclosed. Although the invention is described herein with reference to specific embodiments, many modifications therein will readily occur to those of ordinary skill in the art. Accordingly, all such variations and modifications are included within the intended scope of the invention as defined by the following claims. | A solution for mitigating the effects of EUV substrate surface defects is disclosed. In one embodiment, a layer of polyimide material is formed upon a mask substrate surface, resulting in a substantially defect free surface adjacent to which a reflective multilayer may be positioned for EUV lithography. To reduce the possibility of polyimide outgassing and resultant added roughness to adjacently positioned layers, the layer of polyimide may be cured in a vacuum at an elevated temperature before other layers are adjacently positioned. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a combination tool for use in oil well drilling and production. The tool performs both cutting and retrieving functions within a well bore.
Prior tubing cutters of various types are known, including exposive devices and tools having cutter knives operated by hydraulic pistons to which fluid pressure is directed from the surface. Hydraulic cutters tend to be complex, and therefore expensive and difficult to operate, and explosive devices have well-known shortcomings and dangers Furthermore, none of the prior devices is capable of both cutting a fish and retrieving it from the well in a single operation.
Purely mechanical tubing cutters are also well known. These, as a rule, require that the tubing supporting the tool be rotated at the surface when it is desired to perform a cut. A problem associated with tools actuated by rotary motion occurs when well bores are highly deviated, that is, not straight. Such bores may deviate from the vertical by over 60° . In such cases, wall friction between the casing and the tubing makes rotary motion very difficult to impart and control from the surface.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide a mechanical tubing cutter capable of grasping heavy fish with sufficient force to lift the fish out of the well, and to provide a purely mechanical tool which executes clamping, cutting and retrieving steps in automatic sequence.
Another object is to provide such a tool which is actuated by a linear lifting force, rather than by rotation, and which performs the clamping, cutting and retrieving steps at predictable force levels.
A further object is to provide a tubing cutter which can be easily be converted to a releasing overshot.
The present invention is embodied in a tubing cutter comprising a hollow cylindrical housing containing: a cutter assembly having plural knives with inclined upper cam surfaces, a slip body above the cutter, the body comprising plural cam-operated slips for clamping the tubing by applying radial force thereto, and having a lower conical surface for engaging the upper cam surfaces of the knives, a slip actuator above the slip body, the acutator having a lower conical surface for actuating the slips, and means, above the slip actuator, for engaging a projection on the tubing. The engaging means, the actuator and the slip body are all retained in installed axial positions within the housing by first, second and third shear pins, respectively, the pins having different strengths so as to fail progressively, the first pin being the weakest of the three and the third pin being the strongest. When the device is placed over the tubing and then pulled upward toward the projection with progressive force, the tubing is first engaged by the engaging means, then clamped by actuation of the slips, and then cut by actuation of the cutter.
BRIEF DESCRIPTION OF THE DRAWINGS
A tool embodying the is shown in the accompanying drawings, wherein FIG. 1 is a cross-sectional view of a tubing cutter embodying the invention, taken along a plane containing the longitudinal axis of the tool;
FIG. 2 shows an alternative form of the tool, useable releasing overshot;
FIG. 3 shows the dog assembly of the invention in exploded isometric;
FIG. 4 is an isometric view illustrating operation of the dog assembly;
FIG. 5 shows the tool in clamping engagement with a fish, prior to cutting;
FIG. 6 shows the severed fish being removed from a well bore, and
FIG. 7 shows a variation of the dog assembly, corresponding to FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A tubing cutter embodying the invention includes a cylindrical hollow housing 10 having an open upper end internally threaded at 12 for attachment at the bottom of a wash pipe (not shown). The housing has an integral, annular bottom or "driving ring" 14 with a bore 16 sufficiently large to pass over drill string collars and the like. The housing contains four major components, capable of linear movement with respect to one another within the housing. From top to bottom, these components are: a dog assembly 20 for engaging tubing shoulders or collars in a cutting or fishing operation; a slip body actuator 60; a collet-type slip body 70; and a collet-type cutter 80. The cutter rests normally on the bottom 14 of the housing 10. The cutter, slip body, and actuator each have a pairs of lugs L which extend through corresponding vertical slots S in the housing wall to delimit the vertical motion of each.
Of the assemblies contained within the housing, the dog assembly 20 is uppermost. This assembly, shown in detail in FIGS. 3 and 4, comprises a cage 22 having four equally spaced slots 24 extending radially from the inside diameter 26 to the outside diameter 28 of the cage. A dog 30 is retained within each of the slots, for pivoting movement about a pin 32 which extends through the dog and into the sides 34 of the cage slot. Each dog has a flattened "V" shape and is pinned at the intersection of the legs of the "V".
The cage 22 rests on an antifriction thrust bearing 36 within a cup-shaped dog cam ring 38 having a peripheral annular wall 40. Four equally spaced cam surfaces 42, one facing each of the dogs, are formed on the inner wall surface 44. The lower wing 46 of each dog has a rounded end 48 generally conforming to the shape of the cam surfaces. Clockwise rotation of the ring relative to the cage causes the cam surfaces to push the lower ends of the dogs radially inward, forcing each dog to a more vertical orientation to release a tubing shoulder engaged by the dogs. The necessary rotation is transmitted to the ring from the drill string by a coil spring 58, described below.
The annular wall 40 of the release ring has a radially extending blind hole 50 in its inner surface 44, disposed between an adjacent pair of the cam surfaces 42. The cage 22 has a corresponding hole 52 in its outer surface 54, so positioned that the two holes 50,52 are aligned only when the dogs are in their fully released position. The dog cam ring and cage are assembled with these holes misaligned, in relative positions corresponding to the locking position of the dogs, and a hardened pin 54 is installed in the blind hole in the release ring, with a spring 56 behind it. When the dog cam ring is turned to the release position, as explained below, the pin 54 latches into the hole 52 in the cage, so as to lock the ring and cage in the open position and to thereby prevent further relative rotation.
A right-hand helix coil compression spring 58 (FIG. 1), having an outer diameter about equal to the inner diameter of the housing 10, is positioned below and in contact with the bottom surface of the dog cam ring; the end of the spring is preferably seated in a groove in the ring to prevent relative rotation of the parts. The lower end of the spring is supported on the upper surface of the next lower component, the floating slip body actuator 60, and is correspondingly seated at that point.
The actuator 60 has a flat upper surface 62, an outer diameter 64 that is a sliding fit in the housing, an inner diameter 66 sufficiently large to pass over any fish, and an upwardly converging frustoconical bottom surface 68. The lugs L extending outwardly from the outer diameter of the floating slip body cone into the vertical slots S in the housing to prevent relative rotation.
The slip body 70 is a unitary body comprising a sleeve with a frustoconical upper surface 72 having the same apex angle as the bottom surface 68 of the actuator. A plurality of radially extending slots 74 opening inwardly to the bore of the slip body define plural resilient slip body fingers 76, which are provided with serrated inner surfaces 78 for engaging the wall of a tube. The fingers are internally undercut to make them sufficiently resilient. The bottom surface 79 of the slip body defines the frustum of an upwardly converging cone.
The cutter body 80, like the slip body, is unitary, and has an upper frustoconical surface 82 with an apex angle like that of the bottom surface 79 of the slip body. The upper portion of the body is divided by radial slots 84 into a plurality of knives 86 having inwardly directed chisel edges 88 at their upper ends. The knives are exteriorly undercut so as to have adequate resilience.
The dog assembly, actuator, and cutter are retained in their installed positions, with gaps therebetween, by shear pins 90, 92 and 94 designed to fail at different, predetermined axial force levels. The dog assembly retaining pin 90, for example, is rated at 2500 lbs.; the actuator pin 92 is designed to fail at 10,000 lbs.; and the slip body pin 94 fails at 20,000 lbs. shear. The shear pins provide sequential, predictable clamping and cutting events, and insure that the upper portion of that which is cut remains retained by the tool for immediate removal from the well.
In operation, the tool is run down the well and over the end of the fish. Once the tool is at the desired point on the fish, it is retracted until the dogs engage a shoulder or collar on the fish, as shown in FIG. 5. The upward force on the tool maintains the dogs in firm engagement beneath the shoulder thereafter. The lifting force is then progressively increased. As the shear pin 90 fails, the dog assembly moves toward the actuator, compressing the spring 58. At a lifting force of 10,000 pounds, the shear pin 92 fails, allowing the spring to drive the actuator downward against the slip body, closing the slip body fingers around the tubing. This position is illustrated in FIG. 5. Subsequently, when the lifting force reaches 20,000 pounds, the shear pin 94 is broken, and the slip body is driven downward against the cutter 80, forcing the cutter knives inward against the tubing. The tool may be jarred up and down to complete the cut if necessary. Once the fish is cut, its upper portion, still in the grip of the slip body fingers, may be lifted safely from the well, as shown in FIG 6.
When desired, the cutter knives and slip body may be retracted by bumping the tool downward, sufficiently that the tops of the slots S strike the lugs L. The heights of the slots are selected so that the parts are deactivated in the reverse order of the sequence in which they were activated.
The tool described above may be converted to a releasing overshot merely by replacing the cutter with a simple sleeve 180, as shown in FIG. 2. Now, when the tool is run over a fish, the dogs engage beneath a shoulder of the fish to engage it a provide the resistance to lifting necessary to actuate the tool. Once sufficient force is applied to break the first and second shear pins, the actuator drives the slip body fingers against the exterior of the fish, to clamp it. As the third pin breaks, no cutting occurs, but the upward force created on the clip by the sleeve increases the compression of the slip body fingers, thus enabling extremely heavy fish to be lifted. If, however, the fish is stuck and cannot be removed, the releasing dog feature of the invention permits the supervisor to disengage the dogs from the fish shoulder (by rotating the drill string, and thus, the dog assembly dog cam ring 38) and remove the tool, without damaging it. In the past, it has been necessary to break off the dogs in order to disengage the overshot from the fish.
FIG. 7 shows a variation of the dog assembly wherein the cam surfaces of the dog cam ring 140 are replaced by stepped recesses designated generally as 142, each comprising a shallow recess 142A adjacent a deeper recess 142B. In this embodiment also, the dogs 130 have a radially inner wing 145 and an outer wing 146 with a negative dihedral angle therebetween, so that the dogs pivot downward to release the fish, rather than upward. Otherwise, the assemblies are identical, as shown by identical reference numerals, and operation of the assembly is very similar to that described above. It can be seen that clockwise rotation of the ring 140 permits the dog wing 145 to fall downward, to release the fish.
Inasmuch as the invention is subject to variations, it is intended that the foregoing description and the accompanying drawings shall be interpreted merely as illustrative of the invention, which is to be measured by the following claims. | A mechanical tubing cutter for severing and retrieving fish from wells comprises a slip body for clamping the upper end of the fish, and cam-actuated cutter knives for severing the fish below the slip body. The clamping and cutting operations occur in an automatic and predictable sequence as upward force is progressively applied to the tool. The tool may be used as a releasing overshot merely by substituting a slip body setting sleeve for the cutter knives. | 4 |
This invention relates to a gas turbine engine, and more particularly to the restoration of the dimensions of components of the gas turbine engine.
BACKGROUND OF THE INVENTION
In a gas turbine engine, air is drawn into the forward end of the engine and compressed by a shaft-mounted axial flow compressor. The compressed air is mixed with fuel in the combustors, and the fuel is ignited. The resulting combustion gas flows through and turns a shaft-mounted axial flow turbine, which drives the compressor. The combustion gases flow from the aft end of the engine, driving it and the aircraft forward.
The turbine includes a turbine disk with turbine blades that project radially outwardly into the gas path of the combustion gas. An annular stationary shroud encircles the turbine blades and defines the gas path through which the combustion gas flows. The stationary shroud is circumferentially segmented. The stationary shroud segments are supported from the outer casing of the engine by a set of circumferentially segmented shroud hangers.
The shroud hanger segments are connected to the outer casing with an outer hook structure that allows these components to expand and contract at different rates without warping. Similarly, the shroud hanger segments and the stationary shroud segments are interconnected with an inner hook structure that allows these components to expand and contract at different rates without warping. These floating interconnections, rather than rigid welded or bolted interconnections, are required because of the radial temperature differentials experienced as the gas turbine engine is operated.
While this hook structure is operable and widely used, there are sometimes problems experienced because its required dimensions are not achieved in manufacturing or are lost during service. Similar dimensional-variation problems are experienced with other components of the gas turbine engine as well. There is accordingly a need for an improved approach to maintaining the dimensions of the shroud hanger segments and other structure in the engine. The present invention fulfills this need, and further provides related advantages.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a method for preparing a built-up gas turbine component in which a key dimension is brought within a specified dimensional tolerance. This approach produces a finished part whose built-up dimension is established to within close tolerances, without the need for final machining. The approach uses a non-line-of-sight technique. There is no chipping of the material, as may occur where thermal sprays are used. The process does not introduce any distortion in the finished built-up component. The approach may be applied to both nickel-base and cobalt-base alloys, and to a wide variety of types of components. Examples include shroud hangers, shrouds, and combustor components, with shroud hangers being of most interest.
A method for preparing a built-up gas turbine component includes providing a gas turbine component having a component surface and made of a component base metal having a component base metal composition. The gas turbine component may be either a newly made article or an article which has been in service and is being returned for repair and/or refurbishment. A buildup tape is supplied having a net metallic buildup composition different from the component base metal composition. The buildup tape includes a first metallic constituent having a first melting point, and a second metallic constituent having a second melting point. The first metallic constituent and second metallic constituent together comprise the net metallic buildup composition. The buildup tape additionally includes a nonmetallic binder binding together the first metallic constituent and the second metallic constituent. The method further includes applying the buildup tape to the component surface, and heating the buildup tape and the component surface to a brazing temperature greater than the first melting point and less than the second melting point. The first metallic constituent melts and fuses the first metallic constituent and the second metallic constituent to the component surface as a buildup deposit on the built-up gas turbine component.
The present approach is preferably practiced to adjust the dimensions of a shroud hanger having a forward hook structure including a forward radially outer hook structure having a forward outer hook land structure thereon, and a forward radially inner hook structure having a forward inner hook land structure thereon; and an aft hook structure including an aft radially outer hook structure having an aft outer hook land structure thereon, and an aft radially inner hook structure having an aft inner hook land structure thereon. The step of applying includes the step of applying the buildup tape to at least one of the land structures.
The gas turbine component may be made of a nickel-base superalloy base metal, and the buildup tape typically has a nickel-base alloy net metallic buildup composition. The gas turbine component may be made of a cobalt-base material, and the buildup tape typically has a nickel-base or a cobalt-base composition.
In one form, the nickel-base buildup tape has the first metallic constituent having a first-constituent composition, in weight percent, of from about 10 to about 30 percent chromium, from about 5 to about 12 percent silicon, balance nickel and minor amounts of other elements and impurities, and the second metallic constituent having a second-constituent composition, in weight percent, of about 99 percent by weight nickel, balance minor amounts of other elements and impurities. Preferably, the first metallic constituent has a first-constituent composition, in weight percent, of from about 18 to about 20 percent chromium, about 9.75 to about 10.5 percent silicon, balance nickel and minor amounts of other elements and impurities. The buildup deposit may be of any required thickness, but it preferably has a thickness of from about 0.001 inch to about 0.004 inch, and most preferably has a thickness of from about 0.002 inch to about 0.003 inch.
Thus, for example, a built-up gas turbine shroud hanger is made of a nickel-base superalloy base material and has a hook structure as described above. There is a shroud-hanger buildup deposit on at least one of the hook land structures. The shroud buildup deposit is made of a nickel-base alloy buildup material different in composition from the nickel-base superalloy base material, and is typically an alloy comprising nickel, chromium, and silicon. Other features of the invention as discussed above may be used with this embodiment.
The application of the shroud buildup deposit is most conveniently accomplished by furnishing a braze metal tape, and brazing the braze metal tape to the areas whose dimension is to be increased. The braze metal tape is a multi-component tape, such as a two-component tape, having a net composition required for the buildup material.
When shroud hangers are assembled into a gas turbine engine, it is crucial that the dimensions in the area of the land structures be precise, typically to tolerances of no more than +/−0.001 inch. If the dimensions are outside of these tolerances, the shroud hanger typically does not fit together properly with the case and/or the shroud. New, as-cast and machined shroud hangers and shroud hangers that have seen service often have dimensions of the land structures that are outside of the tolerances in the areas of the land structures, and consequently do not function properly. If the dimensions of the land structures of the new shroud hangers are too large, the excess material may be machined away. If the dimensions of the land structures of new shroud hangers or shroud hangers that have returned from service are under the limits set by the dimensional tolerances, in the past it has been common practice to scrap the shroud hanger. The present approach provides a technique for repairing this problem and increasing the dimensions in the land structures of such shroud hangers, so that the dimensions are within tolerance and the article may be used in service.
Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. The scope of the invention is not, however, limited to this preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial sectional view of an axisymmetric gas turbine case, buildup shroud hanger, shroud, and turbine rotor;
FIG. 2 is a perspective view of the buildup shroud hanger of FIG. 1;
FIG. 3 is an enlarged isolated view of the buildup shroud hanger of FIG. 1
FIG. 4 is a detail sectional view of FIG. 3, taken in region 4 ;
FIG. 5 is a block flow diagram of an approach for practicing the invention;
FIG. 6 is an elevational view of the buildup shroud hanger segment; and
FIG. 7 is a graph of the thickness of the shroud buildup deposit as a function of position on the aft inner hook land of the built-up shroud hanger segment of FIG. 6 .
DETAILED DESCRIPTION OF THE INVENTION
The present invention is preferably utilized in relation to a shroud structure, and most preferably the shroud hanger. A shroud structure for an aircraft gas turbine engine is known in the art, except for improvements discussed herein, and is described, for example, in U.S. Pat. Nos. 5,553,999; 5,593,276; and 6,233,822, whose disclosures are incorporated by reference. FIG. 1 depicts the relevant portion of a shroud structure 20 which is axisymmetric about an engine centerline axis 22 .
The shroud structure surrounds a turbine 24 , illustrated in this case as a high pressure turbine stage. Combustion gas 26 flows from a combustor 27 , shown schematically at the left in FIG. 1 and through the turbine 24 . The turbine 24 includes a turbine rotor 28 that rotates about the engine centerline axis 22 and turbine blades 30 extending radially from the turbine rotor 28 into the flow of the combustion gas 26 .
An outer stator casing 32 is generally axisymmetric about the engine centerline axis 22 . The shroud structure 20 includes a shroud support 34 affixed to the outer stator casing 32 . The shroud support 34 includes a radially inward forward support hook 36 and a radially inward aft support hook 38 .
A built-up shroud hanger 40 is engaged to the shroud support 34 . The built-up shroud hanger 40 is shown in its relation to the other structure in FIG. 1, and in isolation in FIGS. 2-4. The built-up shroud hanger 40 comprises a series of circumferential segments, 14 segments in a typical case. The built-up shroud hanger 40 includes a forward hook structure 42 having a forward radially outer hook structure 44 with a forward outer hook land structure 46 thereon, and a forward radially inner hook structure 48 with a forward inner hook land structure 50 thereon. The forward radially outer hook structure 44 engages the forward support hook 36 of the shroud support 34 . The built-up shroud hanger 40 further includes an aft hook structure 52 having an aft radially outer hook structure 54 with an aft outer hook land structure 56 thereon, and an aft radially inner hook structure 58 having an aft inner hook land structure 60 thereon. The aft radially outer hook structure 54 engages the aft support hook 38 of the shroud support 34 .
The built-up shroud hanger 40 or other component is made of a base metal, preferably a nickel-base superalloy or a cobalt-base alloy. A nickel-base alloy is an alloy that has more nickel than any other element, and a cobalt-base alloy is an alloy that has more cobalt than any other element. A nickel-base superalloy is a nickel-base alloy that has a composition such that it is strengthened by the precipitation of gamma prime or a related phase. Some examples of operable nickel-base alloys that may be the base metal include Rene® 80, having a nominal composition in weight percent of about 14.0 percent chromium, about 9.5 percent cobalt, about 4.0 percent molybdenum, about 4.0 percent tungsten, about 3.0 percent aluminum, about 5.0 percent titanium, about 0.17 percent carbon, about 0.015 percent boron, about 0.03 percent zirconium, balance nickel and minor elements; Rene® 77, having a nominal composition in weight percent of about 14.6 chromium, about 15.0 percent cobalt, about 4.2 percent molybdenum, about 4.3 percent aluminum, about 3.3 percent titanium, about 0.07 percent carbon, about 0.016 percent boron, about 0.04 percent zirconium, balance nickel and minor elements; Rene® N5, having a nominal composition in weight percent of about 7.5 percent cobalt, about 7.0 percent chromium, about 1.5 percent molybdenum, about 5 percent tungsten, about 3 percent rhenium, about 6.5 percent tantalum, about 6.2 percent aluminum, about 0.15 percent hafnium, about 0.05 percent carbon, about 0.004 percent boron, about 0.01 percent yttrium, balance nickel and minor elements; Rene® 142, having a nominal composition in weight percent of about 12.0 percent cobalt, about 6.8 percent chromium, about 1.5 percent molybdenum, about 4.9 percent tungsten, about 2.8 percent rhenium, about 6.35 percent tantalum, about 6.15 percent aluminum, about 1.5 percent hafnium, about 0.12 percent carbon, about 0.015 percent boron, balance nickel and minor elements; and Rene® 41, having a nominal composition in weight percent of about 11 percent cobalt, about 19 percent chromium, about 1.5 percent aluminum, about 3.1 percent titanium, about 10 percent molybdenum, about 0.09 percent carbon, about 0.01 percent boron, balance nickel and minor elements. Some examples of operable cobalt-base alloys that may be the base material of a structure that is to be built up include alloy X-40, having a nominal composition in weight percent of about 0.5 percent carbon, about 1 percent manganese, about 1 percent silicon, about 25 percent chromium, about 2 percent iron, about 10.5 percent nickel, about 7.5 percent tungsten, balance cobalt and minor elements; alloy Mar M509, having a nominal composition in weight percent of about 0.6 percent carbon, about 0.1 percent manganese, about 0.4 percent silicon, about 22.5 percent chromium, about 1.5 percent iron, about 0.01 percent boron, about 0.5 percent zirconium, about 10 percent nickel, about 7 percent tungsten, about 3.5 percent tantalum, balance cobalt and minor elements; L-605, having a nominal composition in weight percent of about 52 percent cobalt, about 20 percent chromium, about 10 percent nickel, about 15 percent tungsten, balance minor elements; and alloy HS 188, having a nominal composition in weight percent of about 40 percent cobalt, about 22 percent chromium, about 22 percent nickel, about 14.5 percent tungsten, about 0.07 percent lanthanum, balance minor elements. These are examples of operable alloys, and the invention is not so limited.
A shroud 62 is supported from the built-up shroud hanger 40 . The shroud 62 has a forward shroud hook 64 which engages the forward radially inner hook structure 48 of the built-up shroud hanger 40 , and an aft shroud hook 66 which engages the aft radially inner hook structure 58 of the built-up shroud hanger 40 . The positioning of the shroud 62 defines a clearance C between the shroud 62 and the tip of the turbine blade 30 . The shroud 62 comprises a series of circumferential segments, 42 segments in a typical case.
Compressor bleed air, indicated generally by arrows 68 , flows around and through the shroud structure 20 to cool it.
As seen in FIG. 4, there is a shroud buildup deposit 70 on at least one of the land structures 46 , 50 , 56 , and 60 . In the pictured example, the shroud buildup deposit 70 is preferably on the aft radially inner hook land structure 60 , and it will be used as the example, but the shroud buildup deposit 70 may be on any of the land structures. After the shroud buildup deposit 70 is deposited on a base-material hook surface 72 of the aft radially inner hook structure 58 , an upper surface 74 of the shroud buildup deposit 70 serves as the aft inner hook land structure 60 . The shroud buildup deposit 70 preferably has a thickness t of from about 0.001 inch to about 0.004 inch, and most preferably has the thickness t of from about 0.002 inch to about 0.003 inch.
The shroud buildup deposit 70 is formed of a buildup material different in composition from the base material that forms the body of the built-up shroud hanger 40 . The base material has a base-material melting temperature, and the buildup material has a buildup-material melting temperature. The buildup-material melting temperature preferably is less than the base-material melting temperature. In the preferred case where the base material is a nickel-base superalloy, the buildup material is a nickel-base alloy. A preferred nickel-base alloy for the buildup material comprises nickel, chromium, and silicon. A most preferred nickel-base alloy for the buildup material has a composition, in weight percent, of about 77 percent nickel, about 15 percent chromium, and about 8 percent silicon, with minor amounts of other elements and impurities present.
FIG. 5 depicts a preferred approach for practicing the buildup procedure. A gas turbine component, preferably the shroud hanger prior to buildup, is provided, numeral 80 . The shroud hanger or other component may be newly manufactured without any buildup deposit 70 thereon. The component may instead be a component that is being returned from service for rework and repair, and may have no buildup deposit 70 thereon or a preexisting buildup deposit thereon. In the case of the shroud hanger, a thickness dimension D of the hook structure, the aft radially inner hook structure 58 in the example, is too small and is below that permitted by the tolerances of the structure. To increase the thickness dimension D of the hook structure, the shroud buildup deposit 70 is applied, numeral 82 , to the relevant under-dimension land structure, the aft inner hook land structure 60 (i.e., the base-metal hook surface 72 ) in the example of FIG. 4 . The shroud buildup deposit 70 is formed of the buildup material and has the thickness as discussed above.
The shroud buildup material 70 may be applied, numeral 82 , by any operable technique. A preferred application technique is depicted in FIG. 5 . The preferred application approach includes furnishing a braze metal of the buildup material composition, preferably as a braze-metal tape, numeral 84 , and brazing the braze metal (tape) to the land structure, such as the aft inner hook land structure 60 as shown in FIG. 4 . The use of the braze-metal tape is preferred because it allows the desired composition and thickness of the buildup material to be precisely applied to the area where it is needed, without deposition on other areas where it is not desired.
The braze-metal tape, where used, may be a single-constituent tape, in which powder particles of the final composition of the buildup material are held together with an organic binder. The braze-metal tape may instead be, and most preferably is, a two-constituent braze metal tape. In the two-constituent tape, one of the constituents has a lower melting point than the other of the constituents. The lower melting point is typically achieved by the addition of elements that depress the melting point. So, for example, the first constituent may have a larger alloy-element content (the total weight percent of alloying elements) than the second constituent, so that the first constituent has a lower melting point than the second constituent. Thus, the second constituent may be nearly pure nickel, and the first constituent may be an alloy with elements added to nickel to depress the melting point (i.e., solidus temperature).
In a preferred case of a nickel-base braze tape, a two-constituent braze tape comprises about 80 percent by volume of a first constituent having a composition, in weight percent, of from about 10 to about 30 (most preferably from about 18 to about 20) percent chromium, from about 5 to about 12 (most preferably from about 9.75 to about 10.5) percent silicon, balance nickel and minor amounts of other elements and impurities, and about 20 percent by volume of a second constituent having at least about 99 percent by weight nickel, balance minor amounts of other elements and impurities. The first constituent has a first melting point, about 2075° F. in the example, and the second constituent has a second melting point, about 2650° F. in the example. The two constituents are furnished as powders held together with an organic binding agent such as polyethylene oxide (PEO). In a preferred case of a cobalt-base braze tape, a one-constituent braze tape has a composition, in weight percent, of about 8 percent silicon, 19 percent chromium, 17 percent nickel, 4 percent tungsten, 0.8 percent boron, balance cobalt and minor amounts of other elements.
The braze-metal tape is applied to the land structure where it is needed to increase the dimension D. The braze-metal tape and the shroud hanger are heated to a brazing temperature. The brazing temperature is below the melting temperature of the base material, below the second melting point, and above the first melting point. The organic binding agent vaporizes during the heating. At this brazing temperature, the first constituent melts and bonds to the base material hook surface 72 . The second constituent remains solid, aiding the mass in holding its desired shape and thickness, rather than running over the surface of the component. In the case of the preferred two-constituent braze tape, the brazing temperature is preferably from about 1900° F. to about 2300° F., most preferably about 2125+/−25° F. Upon cooling, the shroud buildup deposit 70 solidifies as a solid layer of the required thickness on the built-up shroud hanger 40 . The thickness t of the shroud buildup deposit 70 is less than that of the initial braze-metal tape due to consolidation, and the initial thickness of the braze-metal tape is selected with this known shrinkage in mind.
The invention has been reduced to practice using the approach of FIG. 5 with the preferred two-constituent braze tape. FIG. 6 is an elevational view of one circumferential segment of the built-up shroud hanger 40 , upon which the test was performed at two different axial locations on one shroud hanger 40 , indicating circumferential measurement locations 1 - 5 at which thickness measurements of the final thickness t of the shroud buildup deposit 70 were made. The objective was to form a shroud buildup deposit 70 about 0.002-0.0025 inch in thickness. This result was achieved at the different locations as may be seen in FIG. 7, with a slight but acceptable variation between the different circumferential measurement locations 1 - 5 .
Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims. | A built-up gas turbine component is prepared by providing a gas turbine component having a component surface and being made of a component base metal having a component base metal composition. A buildup tape is supplied having a net metallic buildup composition different from the component base metal composition. The buildup tape includes a first metallic constituent having a first melting point, and a second metallic constituent having a second melting point. The first metallic constituent and second metallic constituent together have the net metallic buildup composition. A nonmetallic binder binds together the first metallic constituent and the second metallic constituent. The buildup tape is applied to the component surface and heated to a brazing temperature greater than the first melting point and less than the second melting point. The first metallic constituent melts and fuses the first metallic constituent and the second metallic constituent to the component surface as a buildup deposit on the built-up gas turbine component. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus for filtering particles from a liquid and more particularly to an apparatus for trapping large foreign objects in a wash liquid in an automatic washer.
2. Description of the Prior Art
Automatic clothes washing machines are provided with a pump which among other things recirculates wash liquid within the wash tub. As the wash liquid is recirculated throughout the clothes load, foreign objects such as coins, buttons, bobby pins, toothpicks and other similar objects become entrained in the wash liquid and are carried toward the pump. It is necessary to intercept and trap these foreign objects prior to their reaching the pump so that they will not cause damage to the pump. Various attempts have been made to filter out these foreign objects which can range in size, shape and density from heavy disc shaped objects such as coins and buttons to floatable cylindrical rod shaped objects such as toothpicks. This wide range of sizes, shapes and densities presents a particular filtering problem in automatic washers which the present invention overcomes.
Various means have been employed between the washing vessel and pump to intercept foreign objects, among them being (a) gravity type traps which provide a low water velocity region for heavier than water objects to settle out and collect, (b) grid types, and (c) labyrinth types. All of the above types have various advantages and drawbacks. Type (a), in principle, will only intercept heavier than water objects, while objects of wood or light plastic such as toothpicks will pass. An advantage is that the objects trapped will not typically accumulate lint, partly because they are out of the main water stream and partly because they are free to shift position easily. This type also requires several inches of vertical space which may or may not be readily available. Type (b), can be made to intercept objects as small as desired and of any material, but will typically accumulate lint on both the grid and the objects intercepted. Eventually the accumulation of lint will restrict waterflow through the system unless removed. Removal of the lint is a nuisance and is dependent on the vigilance of the operator. Type (c), can be made to intercept objects of almost any size, shape and material. It can also be made to pass lint, at least when free of foreign objects. However, the accumulated foreign objects tend to take on the characteristics of a grid and collect lint themselves. This is especially true if the objects are held in a region of high water velocity and restricted freedom to move about and thereby, perhaps, release their lint.
U.S. Pat. No. 2,919,568 discloses a straining device which is adapted to prevent the passage of long narrow objects such as nails, matches, paper clips and bobby pins which comprises a plate having circular perforations therein which is positioned fairly close to the bottom wall of the tub and has the perforations spaced laterally from the drain opening such that long cyindrical shaped objects are unable to pass through the perforations to the drain opening.
U.S. Pat. No. 3,006,477 discloses a filter which utilizes a settling chamber and two annular outlet passageways to remove lint and heavy articles from the wash water.
U.S. Pat. No. 3,236,386 discloses a foreign articles trap wherein wash liquid is directed through an annular opening and through two 180 degree turns and which also employs an annular settling chamber.
U.S. Pat. No. 3,590,606 discloses a tube in the foreign objects trap arranged with the outlet spaced between the top and the bottom of the outer tube such that heavier than water objects settle to the bottom of the tube and lighter than water objects float to the top of the outer tube while the washing liquid passes out the outlet opening.
U.S. Pat. No. 1,254,025 discloses a filter screen for use in removing sand, gravel and other sediment from water lines in which a cylindrical or flat circular screen is used which has perforations therethrough with outwardly extending fingers or projections which are used to protect the perforations from clogging.
U.S. Pat. No. 2,533,422 discloses a house gutter screen which is used to prevent leaves and twigs from collecting in house gutters in which a plate is used to cover the gutters which has a plurality of domes embossed in the plate having side openings forming drain openings. The domes are used to hold flat solid objects such as leaves away from the drain openings so that water can drain easily into the gutters while the leaves and other debris are kept out of the gutters.
SUMMARY OF THE INVENTION
The present invention provides for a foreign objects trap which is to be used in an automatic washer to prevent foreign objects from entering the wash container inlet port along with the wash liquid. The foreign objects trap does permit lint to pass through and not accumulate in the trap. The trap utilizes a settling chamber in conjunction with a grid type plate having irregular shaped openings therethrough closely associated with the walls of the trap such that foreign objects are prevented from passing through the grid but lint is allowed to pass without accumulating.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a horizontal axis washer and showing the path of wash liquid from the sump through the pump to recirculate or to drain.
FIG. 2 is a partial side sectional view of the foreign objects trap of the present invention.
FIG. 3 is a top sectional view of the foreign objects trap partially cut away and taken generally along the lines III--III of FIG. 2.
FIG. 4 is a bottom sectional view of the foreign objects trap taken generally along the lines IV--IV of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 there is shown an automatic washing machine 10 of the horizontal axis type, having a cylindrical imperforate tub member 12 carrying a perforate basket 14 therein. A pump 16 is provided to recirculate wash liquid through a return conduit 18 or to pump wash liquid to a waste drain through a conduit 20 depending on the position of a valve 22 which is automatically controlled by a solenoid 24. The wash liquid collects in a sump area 26 at the bottom of the tub 12 and passes through a foreign objects trap shown generally at 28 prior to entering the pump 16 through an inlet conduit 30.
As seen in greater detail in FIG. 2, the sump area 26 of the tub 12 is comprised of a sloped side wall portion 32 which is integrally connected at its top with the imperforate tub 12 and which has a horizontal bottom wall 34 with a central well 36 therein.
The foreign objects trap 28 is comprised of an upper housing 38 preferably formed of an elastomeric material and which has at an upper end a cylindrical neck portion 40 with a circular opening 42 therethrough and having a flanged end 44. The well portion 36 of sump 26 has a circular opening 46 therethrough and the neck portion 40 of the upper housing 38 is sized to be received in the well opening 46 such that the flanged area 44 covers a portion of the wall of the well 36. An edge 48 of the wall forming the opening 46 is received in a groove 50 just below the flanged top 44 such that a water tight seal is effected between the upper housing 38 and the well 36 of the sump 26.
A lower housing 52 is provided which is constructed of a relatively rigid material and is seen in FIGS. 2 and 4 as being of a generally cylindrical shape. The lower housing 52 has a circular flat bottom wall 54 and a first cylindrical side wall 56 formed at right angles to the bottom wall and projecting from the circumference of the bottom wall. A second cylindrical wall portion 58 is formed integrally with the first wall portion 56 but projects slightly radially outwardly in a stepped manner as seen at 60 thereby providing a ledge surface 62 around the inner circumference of the walls 56, 58.
A separator plate or baffle 64 comprises a generally circularly shaped plate 66 with a central tubular portion 68 projecting upwardly from the plate 66. A cylindrical wall 70 is formed on the outer circumference of the circular plate 66 and is sized to seat in the ledge area 62 of walls 56 and 58. Wall 70 has a height such that a top end 72 is coplanar with a top end 74 of wall 58. The central tubular portion 68 of separator plate 64 is sized to extend up into and be snugly received by neck portion 40 of the upper housing 38. The tubular portion 68 has an open passage 76 therethrough which is of the same size as opening 42 in the neck portion 40 of upper housing 38.
The upper housing 38 has a downwardly extending cylindrical flange 78 which is sized to snugly receive wall portion 58 of the lower housing 52. A circular clamp 80 encircles the flange wall 78 and thereby holds the lower housing 52 and separator plate 64 in fixed relationship with the upper housing 38. The pliant nature of the elastomeric flange 78 provides an effective water tight seal between the upper housing 38 and lower housing 52 when the circular clamp 80 is secured in place. As seen in FIGS. 3 and 4 ends 82 and 84 of circular clamp 80 are turned outwardly so that the two ends can be manually squeezed together thereby loosening circular clamp 80 to facilitate removal of the lower housing 52 from the upper housing 38.
The upper housing 38 has a generally circular horizontally disposed wall portion 86 which is integrally connected at its outer circumference with flange 78 and which extends radially inwardly to a tubular vertically aligned wall portion 88. The upper surfaces 72 and 74 of walls 70 and 58 abut against a lower surface 90 of circular wall 86 such that the circular plate 66 of separator plate 64 is retained in a specific spaced relationship from the lower wall 54 of lower member 52 as defined by the height of the ledge 62 and from the circular wall 86 of the upper housing 38 as defined by the height of the wall 70.
The tubular wall 88 of upper housing 38 is spaced radially outwardly from the tubular wall 68 of the separator plate 64 so as to provide an annular space 92 between the tubular walls 68 and 88. Extending between walls 86 and 88 of upper housing 38 are a plurality of triangularly shaped struts 94 which are utilized to retain the perpendicular relationship between walls 86 and 88.
Upper housing 38 additionally has a horizontally disposed tubular extension wall 96 which projects radially outwardly from the annular space 92 and has an interior passage 98 which communicates with the annular space 92. The conduit 30 which communicates with the inlet port of the pump 16 is snugly received in passage 98 and a second circular clip 100 is used to provide a water tight seal between tubular wall 96 and conduit 30.
The circular portion 66 of separator plate 64 is provided with a plurality of irregularly shaped tubes 102 such as the C-shaped tubes seen in FIGS. 3 and 4. The tubes 102 are of a width and shape such that coins and buttons will not pass therethrough. Curvature of the tubes is critical, especially in blockage of plate shaped objects such as coins. Openings 104 in the tubes 102 form slots which should neither be so narrow that they are readily bridged by lint nor so near together that strands of lint will wrap around the intervening material.
The tubes 102 have boss portions 106 and 108 extending below and above, respectively, the plate 66 of the separator 64 such that there is a passage 110 through the interior of the tubes. The tubes 102 are positioned on the plate 66 such that the passage 110 communicates with a region 112 above plate 66 of separator plate 64 and below wall 86 of upper housing 38 at a top end and a region 114 comprising a settling chamber which is below the circular plate 66 of separator plate 64 and above bottom wall 54 of lower housing 52. A top end 116 of tubes 102 is spaced a short distance 118 below the bottom surface 90 of wall 86 and a bottom end 120 of tubes 102 is spaced a short distance 122 above wall 54 such that elongated objects such as toothpicks cannot enter passages 110 from space 114.
In operation, the device functions as follows: whether during the recirculation of the wash liquid for wash purposes or during machine drainage, wash liquid passes from the sump area 26 of the washer tub 12 into the passageway 76 within the foreign objects trap which communicates with the well 36 of the sump 26, and spreads out into the region 114 below the plate 66 of the separator 64 where heavy objects settle out of the flow. The wash liquid then passes upward through the tubes 102, collects in annular area 92 and then passes to the pump through the passageway 98 and conduit 30. Because the region 114 below the collector plate 64 is of greater volume than the opening 42, water velocity drops in region 114 allowing heavier than water objects to drop to the bottom of the lower housing 52 and usually stay there. The tubes 102 are of a width and shape such that coins and buttons will not pass. Curvature of the tubes is critical, especially in blockage of plate shaped objects.
Certain relationships exist between the size of the spaces 118, 122 between the end of the tubes 102 and the walls 86 and 54, the width of the tubes, the length of the tubes, and the radius of curvature of the tube openings. As the length of the tubes becomes greater and as the width, radius and distance from the tubes to the walls become smaller, the length of a rod type object that the device will pass becomes smaller. Therefore it is possible to tailor the design to block objects greater than some selected length. However, trade-offs exist related to the volume of region 114 to store objects, and open area of the tubes to pass water and lint. Also, the distance 118 must be greater than the distance 122 so that objects which can pass into a tube can pass out into region 112. Otherwise, objects might become permanently stuck in the tubes and become lint catchers.
The relationship between the diameter of the opening 42, the opening 124 at the bottom of the cylindrical wall 68, and the distance 126 between the circular plate 66 and the bottom wall 54 should be such that rod shaped objects up to about 60 millimeters long can pass from opening 42 and lie flat on the bottom of the lower housing 52. Otherwise, these objects can become lint collectors.
While lighter than water objects such as toothpicks may temporarily position themselves across a tube opening while wash liquid is flowing steadily through the system, they will immediately shift when the pump loses prime or stops. This action will tend to release any lint that has become entangled with the rod shaped object. Similarly, heavy objects that have settled in the bottom are free to shift around, by virtue of the size of region 114, and thereby release lint. Bleed holes 128 in the tubular wall 68 are necessary to let air escape from the pump.
Diameter and depth of the region 114 are visualized as great enough that the device would not require emptying in the normal machine life. Likewise, since the device offers no point to snag and hold lint, there is not expected to be a progressive lint accumulation which would develop. To the contrary, should lint accumulate in the area 114 due to one or several successive very linty wash loads, this accumulation will break up and dissipate over the course of several subsequent more normally linty loads. However, should area 114 become clogged, the device permits relatively easy cleaning by removing circular clamp 80 and pulling the lower housing 52 out of the upper housing 38. The lower housing 52 may be made of a transparent material such as styrene acrylonitrile to facilitate observation of the condition of the trap by a service technician. The foreign objects trap will also serve as a water trap to block pump noise from reaching the tank when the pump loses prime. | A foreign objects trap for an automatic washer is provided in the wash liquid flow path just upstream of the pump which has a settling chamber and a separator plate to trap foreign objects. The separator plate has irregularly shaped tubes therethrough which, in conjunction with a closely spaced wall of the trap housing, prevent passage of lighter than water objects. A lower portion of the housing is removable for cleaning and is transparent for visual inspection. | 3 |
PRIORITY CLAIM
[0001] The present application claims benefit under 35 USC Section 119(e) of U.S. Provisional Patent Application Ser. No. 61/050,019 filed on 2 May 2008. The present application is based on and claims priority from this application, the disclosure of which is expressly incorporated herein by reference.
BACKGROUND
[0002] The present invention relates to a device adapted for use on the rear portion of an off-highway or construction vehicle to improve the unrolling of geotextile materials as commonly used in road-beds, landscaping, retention walls, pond-lining, and the like. And, more specifically, the present invention relates to a device that couples to a conveyered material placement vehicle to simultaneously and continuously dispense fabric from a roll as an aggregate is placed on top of the dispensed fabric.
[0003] Certain construction techniques for roadbeds, drainage ditches, man-made ponds and other landscaping needs require a cloth or fabric liner layer to be placed on the newly prepared and compacted soil. This cloth or fabric liner typically arrives at the construction site in large roles varying from about 3-feet to about 15-feet in width and (unfurled) having lengths of 300 feet or more for landscape rolls and about 13-feet wide or about 15-feet wide for road-bed fabric rolls, for example.
[0004] Fabric rolls used in road construction, landscaping and the like are generally known as geotextiles and are defined by the American Society for Testing and Materials (ASTM) as any permeable textile material used with foundation, soil, rock, earth as an integral part of a construction project, structure, or system and may be synthetic or natural fibers, or both. Geomembranes, also used in similar applications, are continuous membrane-type liners or barriers that have low permeability to control migration of fluid and restrict fluid flow.
[0005] In the road construction industry there are essentially four primary uses for geotextiles: separation, drainage, filtration, and reinforcement. However, most often geotextiles are used for stabilizing roads through separation and drainage. Stabilization results from the geotextile acting as a barrier to migration of fines in the subgrade to the base layer (aggregate layer), while simultaneously permitting water to migrate from the base layer to the subgrade or laterally away from the roadbed. Migration of fines is highly undesirable because it weakens the road structure.
[0006] Geotextiles are well suited for temporary road construction, particularly in environmentally sensitive areas where a biodegradable woven jute geotextile can be used. Geotextiles are economical for temporary road construction, such as construction roads in isolated areas as are needed to install power grid infrastructure, wind-turbine power generations, or remote logging roads, for example.
[0007] Such roads, for example, use a crushed aggregate layer on top of native subgrade material. A geotextile serves as a separation layer between the subgrade and the aggregate, preventing intermixing of the two layers. Intermixing occurs (absent the geotextile layer) from pressure exerted on the road from vehicles, the downward and laterally moving load creates a pump-like affect that draws fines in the subgrade upward, intermixing in the aggregate layer. This affect becomes more dramatic when there is water migration as well.
[0008] Thus, proper selection and installation of a suitable geotextile is vitally important in road construction. The installation method for geotextiles (or fabric rolls), as generally known in the art, requires shaping the roadway subgrade, rolling the fabric down the road one lane per roll, and if windy, weight the sides of the unrolled fabric with shovels full of gravel or use spikes or staples to pin the fabric down. Then, dump and spread the gravel or base course material using normal methods with an end dump truck (or belly-dump or side-dump trucks)—but making certain to avoid driving onto the geotextile with any equipment other than rubber-tired vehicles operating over a solid sub-grade in a straight line with no turns and a vehicle speed of no more than seven miles per hour or otherwise risking a puncture or tear, damaging the fabric and making it less suitable for its intended use.
[0009] Currently, the tools and methods to unroll these large fabric rolls include a hanger bar coupled to the rear of a vehicle, such as a dump truck (belly, side, or end) or a front-end loader using the bucket to suspend a roller bar and reversing to unroll the material. The hanger bar supports a roll bar adapted to slideably receive a roll of material. Then, several workers unroll a portion of the roll, stand on it, pin it, or manually shovel some aggregate (e.g. gravel) on the roll to hold it in place. Next, the vehicle advances and unrolls the fabric as the vehicle travels. To hold the fabric in place, the army of workers shovels aggregate, or use spikes to pin the fabric to the sub-grade. Only after the fabric is fully installed, then a second aggregate delivery truck (dump truck), backs to the fabric—to avoid driving on the fabric, which could rip or tear the fragile material—and then dumps the aggregate. Next, a third vehicle (bull-dozer) distributes the piled aggregate on top of the fabric. This is a tedious and time-consuming procedure that must be repeated for the entire length of the road, which could be several dozens of miles.
[0010] The state-of-the-art method of installing fabric sheets, according to the “North Carolina Forestry BMP Manual”, Appendix 4 at page 222 of 243 (amended 2006) publication date unknown, includes shaping the roadway and establishing the crown; rolling the fabric, weight the sides and end of the unrolled fabric with shovels full of gravel, or use spikes to pin the fabric down. This method, however, has certain drawbacks. One drawback includes puncturing the fabric with spikes or staples to pin the material: it is undesirable to puncture the fabric as this causes rips and tears in the sheet, and the punctures themselves enable the base layer to intermix with the aggregate layer, which weakens the roadbed. Manpower cost associated with shoveling aggregate on top of the unrolled sheet to weight it down is yet another drawback of this known method.
[0011] Certain devices are known to facilitate the laying of paving fabric along a roadbed. For example, U.S. Pat. No. 4,456,399 issued on 26 Jun. 1984 to Conover describes an apparatus for laying paving fabric comprising a core support member of an adjustable length for supporting a roll of paving fabric on a vehicle, a tension applying apparatus secured in the proximity of the fabric roll to remove wrinkles from the web prior to the application to the roadbed, and a broom apparatus for facilitating adherence of the web to the roadbed and a guard for the broom for reducing wrinkling of the fabric.
[0012] Yet, there remains a need for improved methods and devices that improve the installation of geotextiles and similar fabric rolls, particularly on temporary road-bed projects. Such tools and methods should minimize worker exposure to injury, reduce manpower required, and reduce expense of installation through time and manpower efficiencies. An improved device and method is needed that enables the unrolling of the fabric roll without requiring spikes to penetrate the fabric to pin the roll in place (as needed, for example, in windy conditions). It would further be desired to have a tool and method that improves efficiencies by combining the rolling of the fabric with the delivery of the aggregate. Such a device, in addition, should be easy to transport to the job site on existing vehicles. Further, such an improved device should be easy to assemble and disassemble by one person.
SUMMARY OF THE INVENTION
[0013] The present invention includes improved devices and methods to simultaneously unroll geotextile fabric and place aggregate on top, without requiring spikes or staples to pin the fabric in place.
[0014] In one preferred embodiment, the present invention consists of a conveyered material placement vehicle adapted to hold multiple widths and lengths of road bedding cloth or landscape cloth. The vehicle includes two receiver hitches welded, attached or otherwise coupled on opposite sides of the rear bumper, approximately seven feet between each other. The pair of receiver hitches slideably receive a corresponding square steel tube or round pipe having a through hole at one end, which enables the retaining pin of the receiver hitch to pass through the receiver hitch and the end of the steel tube when inserted in the hitch. The pair of horizontally disposed steel tubes protrude generally perpendicular from the rear bumper of the vehicle and serve as mounting arms for an approximately 16-foot length of square steel tubing (or similarly sized round pipe of about 2-inches in diameter) that serves as the hanger bar, which arranges generally parallel to the rear bumper of the vehicle and shares the vehicles centerline, but is offset from the rear bumper by a length determined by the pair of steel tubes, which are of a length to clear the device from the operation of the conveyered aggregate delivery apparatus mounted to the rear portion of the vehicle.
[0015] The hanger bar includes a pair of end caps and half links are welded to the end caps, and a pair of eye-loops are additionally welded to this bar. A segment of about 2-feet in length of chain hangs from each end cap half links. This pair of chain segments supports a roller bar, which has a round cross section and adapts to suspend a fabric roll and allows the roll to rotate freely on the bar. The roller bar is further adapted to receive varying lengths of fabric rolls by means of several positioned through-holes, which adapt to receive lock-pins. Thus, a pair of locking plates can be positioned on the roll bar, and secured from sliding by the locking pins, ensuring the fabric roll remains in fixed position relative to the vehicle centerline. The roller bar is pre-drilled at about 15-foot and about 13-foot lengths, which represent standard roll widths commonly used in road building.
[0016] A mesh assembly fabricated from about five about 16-feet to about 18-feet lengths of chain form the long (vehicle) axis of the grid, while about twelve segments of about 3.5-feet of chain create the cross axis of the grid. In stead of chain segments, a heavy cable could also be used to form the mesh grid. Similarly, a grid of solid or hollow metal bars or pipes could be arranged to drag on top of the fabric and, although not optimal for curves, the rigid grid members could serve the same function as the mesh assembly fabricated from chain segments.
[0017] A dragger bar adapts to accept the five long chains (or cable or rigid bar segments), thus dragging the dead-weight member behind the vehicle. The dragger bar is positioned to carry the chain on top of the fabric roll, weighting down the roll as it rests on the roller bar.
[0018] With receiver hitches, roller bar, hanger bar, cloth roll, and dragger bar with chains in place, the cloth is initially held down with the weight of the dragger bar chains as the conveyered material placement vehicle moves forward. The conveyered material placement vehicle then begins to place gravel on top of the cloth as it proceeds in a forward motion, driven via a remote controlled drive system. The conveyered gravel placed on top of the cloth keeps the cloth flat and firmly held on the subgrade even in windy conditions. The operator stops the truck when the roll is empty, un-clips the roller bar from the hanger bar, slides out the spent roll, places the new roll on the roller bar, lifts the dragger bar from the pair of L-hooks on the hanger bar and sets the dragger bar on the ground. Then, the new roll on the roller bar is re-clipped to the hanger bar, and the dragger bar is lifted back on the L-hooks, automatically positioning the dead-weight member on top of the new fabric roll.
[0019] A preferred embodiment of the present invention includes a device consisting of sub-components sized and weighted for one worker to remove from the vehicle when in the transport mode, assemble the components, attach the device to the receivers on the vehicle and disassemble when the job is complete.
DRAWING
[0020] FIG. 1 is a front view of a preferred embodiment of the present invention.
[0021] FIG. 2 is an off-set right-side view of the embodiment of FIG. 1 .
[0022] FIG. 3 is a partial, off-set right-side view of the embodiment of FIG. 1 .
[0023] FIG. 4 is an off-set left-side view of the embodiment of FIG. 1 .
[0024] FIG. 5 is a partial detail view of a component of a preferred embodiment of the present invention.
[0025] FIG. 6 is an off-set frontal view of one embodiment of the present invention and shows a step according to a preferred method of the present invention.
[0026] FIG. 7 is an off-set right side view of one embodiment of the present invention and shows another step according to a preferred method of the present invention.
[0027] FIG. 8 is a partial front view of one embodiment of the present invention and shows another step according to a preferred method of the present invention.
[0028] FIG. 9 is a front view of one embodiment of the present invention and shows another step according to a preferred method of the present invention.
[0029] FIG. 10 is an off-set frontal view of one embodiment of the present invention and shows another step according to a preferred method of the present invention.
[0030] FIG. 11 is a front view of one embodiment of the present invention and shows another step according to a preferred method of the present invention.
[0031] FIG. 12 is a possible environment of use of one embodiment of the present invention and depicts an aggregate delivery vehicle dispensing aggregate onto a fabric roll on a roadbed.
DESCRIPTION OF THE INVENTION
[0032] Possible preferred embodiments will now be described with reference to the drawings and those skilled in the art will understand that alternative configurations and combinations of components may be substituted without subtracting from the invention. Also, in some figures certain components are omitted to more clearly illustrate the invention.
[0033] FIGS. 1-5 illustrate a first preferred embodiment of the present invention. The present invention includes a mechanical implement 10 , specifically, for example, a device utilized to unroll and fixably locate a geotextile 10 fabric for roadbed construction. The implement (device 10 ) adapts to couple to a rear portion of a vehicle frame (V), for example, a conveyered aggregate delivery vehicle, or more broadly a conveyered material placement vehicle, as used in roadbed construction, by cooperating with the vehicle's forward travel to unroll the fabric roll and incorporating a unique and novel dead-weight member 110 , such as a heavy yet flexible cable, rope, tubes or assembly of chain segments arranged in a mesh grid assembly to weight the recently unrolled fabric on top of the prepared sub-grade.
[0034] FIG. 1 , a front view of a preferred embodiment of the present invention, illustrates most of the major components including a support frame including a stinger member 20 , which releasable couples to the vehicle frame V and carries the principal horizontal support or hanger bar 50 . The support frame further includes a hanger bar arranged generally perpendicular to the long-axis of the vehicle frame and extending from about 6-feet to about 10 feet on each side of the vehicle's center line for a total length from about 12-feet to about 20-feet. The hanger bar includes a pair of oppositely mounted winches 60 on each extremity of the length of the bar. The winches enable workers to position and lift the relatively heavy rolls of fabric (once located on the roller bar 70 , discussed below) relative to the hanger bar and determines the height of the roll from the ground and relative to the vehicle frame. Further, opposite ends of the hanger bar each include a chain loop or hook 52 (or other attaching means) from which a first and second chain segment 72 suspends.
[0035] The chain segments 72 , in turn, support a roller bar 70 . The roller bar supports rolls of geotextile fabric as generally understood in this art. The roller bar releasably couples to the chain segments 72 at a corresponding first and second roller-bar end, each end has a corresponding end cap 74 with half-link 76 chain support means (such as a hook, receiver, quick-connect, or other coupling means) adapted to enable the chain segments 72 to attach and un-attach as needed to swap a spent roll for a new roll of fabric. Additionally, a winch cable 62 from the pair of winches 60 on the hanger bar 50 equally releasably attach to the roller bar by means of the half-links 76 .
[0036] Also suspended from the stinger assembly 20 , a dragger bar 90 arranges generally parallel to the roller bar 70 , and positions intermediately between the vehicle and the roller bar. The dragger bar includes a plurality of attaching means 92 consisting of hooks or half-links or chain, or other similar device adapted to selectively and releasably couple a link of chain to the dragger bar. A dead-weight member 110 adapts to couple (not shown in FIGS. 1-5 ) to the dragger bar at the attaching means 92 . Thus, the dead-weight member positions over the roll of fabric located on the roller bar (the roll of fabric is not shown in FIGS. 1-5 ) and extends rearward beyond the vehicle.
[0037] In the various embodiments and figures, the long horizontal members, specifically, the hanger bar 50 , the roller bar 70 and the dragger bar 90 are depicted as rigid members, solid with hollow centers having a fixed length. However, those skilled in the art will appreciate that these horizontal members may have a solid core or, alternatively, may include telescoping features to enable the bars to extend and retract to various desired lengths corresponding to transport of the device, or as needed for varying widths of the road bed, fabric roll, or application of use, for example.
[0038] For example, the hanger bar 50 , in another preferred embodiment (not illustrated in the accompanying figures) comprises a hanger member coupled to the vehicle via stinger arms 22 . The hanger member has an length of about 8-feet to about 10-feet long, or about the width of the vehicle to which it attaches. The hanger member further is adapted to receive a first and second hanger arm at opposite ends of the hanger member: Accordingly, the hanger member may be solid, with the arms inserting over the bar, or, preferably, the hanger member has a hollow core, and the arms slide inside a portion of the exposed ends of the member. The member is further configured with several though holes, arranged to correspond to similar through holes in the associated hanger arm so that a retaining pin can fixably secure the arm inside the member. In addition, the at least one hanger arm (adapted to slidebly engage a portion of the hanger member) effectively provides an adjustable and variable length hanger bar from which the roll bar suspends. It will be appreciated by those skilled in the art that this embodiment enables a geotextile roll to be positioned off-center from the vehicle, or on center with the vehicle, as needed by the application. Further, should a more narrow installation process be involved, for example, re-paving a single vehicle lane on an existing roadway or installing a geotextile roll in a roadside ditch, the present invention more readily adapts to this use.
[0039] Making general reference to FIGS. 1-11 , details of preferred embodiments of the present invention are further discussed, below. In one preferred embodiment, a geotextile-roll applicator device 10 for a vehicle frame V comprises a means for coupling the device to the vehicle frame, such as a stinger member 20 and pair of receiver hitches 30 . The receiver hitches 30 mount to the vehicle frame by any means well understood in this art including, but not limited to, welding to the frame of the vehicle. A suitable receiving hitch 30 includes a standard square receiver commonly available for tow-hitch applications as understood in this art. The stinger member 20 slideably inserts into the receiver hitch and a hitch pin 32 engages a through-hole in the stinger member and receiver hitch, while a pin chain prevents misplacing the pin when not inserted in the hole.
[0040] The stinger member 20 consists of a pair of horizontal stinger arms 22 arranged generally parallel to the long-axis of the vehicle and extending outward from the rear portion of the vehicle. Each stinger arm 22 includes a first arm-end adapted to slideably insert into the respective receiver hitch, an oppositely disposed second arm-end including a connecting means such as a U-shaped hook 24 (or other similar releasably coupling apparatus or means), and a vertically arranged holder leg 26 disposed intermediate to the first and second arm ends at holder-leg first end. The holder-leg 26 further includes a holder-leg extension member 28 adapted to slideably engage the holder-leg at a holder-leg second end and a pin cooperating with pin-receiving holes aligned on both the extension and leg locates and secures the extension relative to the leg. A connecting member, such as an L-shaped hook 29 , locates at the free end of the extension 28 . This L-shaped hook adapts to receive the dragger bar 90 , discussed below. Thus, the position of the L-shaped hook relative to the ground, vehicle, and importantly, to the roller bar 70 can be adjusted by sliding the extension member 28 in or out of the leg 26 and securing the desired position with the pin 27 .
[0041] The roller bar 70 suspends below the hanger bar 50 by a first and second suspension means consisting of two oppositely positioned and cooperating chain segments 72 . The roller bar adapts to support a roll of geotextile fabric and enables the roll to rotate on its roll-axis to dispense the fabric conventionally. The roll bar, in one preferred embodiment, includes a circular cross section, however a square cross section, oval, elliptical or rectangular cross section will work as well. A spacer plate 80 , or preferably a pair of spacer plates adapt to arrange on the roller bar and lock into position by a locking means for selectively and releasably coupling the spacer plate in a first fixed position on the roller bar. The locking means comprises a pair of spacer pins 82 that cooperate with features on the roller bar. The spacer plate enables locating the roll of fabric in a particular position relative to the center-line of the vehicle and maintains the roll in that desired position as the vehicle travels forward. Accordingly, the roll of fabric can be placed in the center, as required for a road-bed, or off center as may be required to lay fabric for a drainage ditch or retaining wall, for example. In a preferred embodiment, the roll-bar has pre-arranged pin-receiving holes at about 13-feet between cooperating holes and at about 15 feet, representing two standard widths of roll fabric. Additionally, each pin attaches to a cable coupled to its corresponding plate 80 to avoid loosing the pin when not inserted in the roller bar.
[0042] In one preferred embodiment, the hanger bar 50 carries a pair of cooperating and oppositely positioned winches 60 . However, in other preferred embodiments the winches may be omitted without detracting from the invention. Additionally, the accompanying figures illustrate a set of hand-operated winches: However, electric or hydraulic-powered winches would work equally well. Each winch includes a winch cable 62 that selectively couples to the roller bar. Then, by cranking the winch handle, the loaded roller bar can be positioned relative to the hanger bar and the chain segments 72 are attached to carry the load and the winch cable can be released and retracted for subsequent use.
[0043] A dead-weight member 110 having a generally grid-like layout comprising interconnected segments of chain loops, releasably couples to the dragger bar 90 . The dead-weight member consists of five generally parallel drag chains measuring about 15-feet to about 25-feet (preferably about 18-feet) in length and extending from the dragger bar behind the vehicle. At a spacing of about 2-feet to about 4-feet (preferably about 3.5 feet), each drag-chain includes a cross-member link chain. Thus, a grid pattern of about a 3.5-foot square grid with five columns is formed. This grid can, alternatively, be formed from cables or bar-segments in lieu of chains.
[0044] FIGS. 6-11 illustrate a first preferred method of using the device 10 of the present invention. Accordingly, this preferred method for dispensing a roll of geotextile fabric using a conveyered aggregate delivery vehicle having a frame adapted to couple to a geotextile roll applicator device, the method comprises: providing a geotextile roll; unrolling a portion of the geotextile; placing a dead-weight member provided by the applicator device over the roll and extending the dead-weight member onto the portion of unrolled geotextile; dispensing an amount of aggregate using the conveyered aggregate delivery vehicle; and advancing the vehicle forward thus causing the geotextile roll to unroll and the dead-weight member to drag on top of the newly unrolled geotextile and continuing dispensing aggregate as the vehicle advances forward.
[0045] Additionally, this method further includes steps of providing a remote control drive system for the vehicle and advancing forward the vehicle with the remote control drive system.
[0046] In another preferred embodiment, the present invention contemplates a system for dispensing geotextile fabric. The system comprises a vehicle having an aggregate dispensing mechanism that is operable to dispense aggregate from one end of the vehicle; and a geotextile-roll applicator device coupled to the vehicle adjacent the end from which aggregate is dispensed, the applicator device being configured to support a roll of geotextile fabric and dispense the fabric from the roll; wherein when the vehicle is moved along a path, the applicator device is operable to dispense fabric onto the ground along the path and the aggregate dispensing mechanism is operable to dispense aggregate from the vehicle onto the dispensed fabric.
[0047] FIG. 12 illustrates another preferred method of the present invention includes a method for dispensing geotextile fabric from a roll. The method includes the steps of supporting the roll of fabric on an applicator device, which is coupled to a vehicle; moving the vehicle along a path; and dispensing fabric from the roll onto the ground along the path as the vehicle is moved and simultaneously dispensing aggregate from the vehicle onto the dispensed fabric.
[0048] When the device 10 is not in use, for example, when it is being transported to and from a job site, the entire device dis-assembles and compactly stores on the vehicle by means of a T-rack 130 . The T-rack adapts to insert in a receiver hitch arranged vertically on the vehicle frame. The T-rack cooperates with the conveyer rack provided by the vehicle.
[0049] The various components of the preferred embodiments of the present invention are generally about 1-inch to about 2-inch square or round tube steel members welded or bolted, as conventionally understood in the art, or—as described herein—adapted to releasably couple to mating components by hooks or other fasteners as described or as would be generally understood in this art. And, although steel is contemplated, other materials would work equally well including aluminum, for example. Further, the various embodiments of the present invention and methods show a material placement vehicle (such as a conveyered aggregrate delivery truck, such as a Super Stone Slinger brand aggregate delivery vehicle available from W.K. Dahms Mfg. Ltd., of St. Jacobs, Ontario, Canada), it will be appreciated by those skilled in this art that other vehicles—including side-dump, belly-dump, or rear dump trucks—can be adapted to work with the device 10 , and may only require additional manpower or equipment to distribute aggregate on top of the unfurled geotextile.
[0050] Although the invention has been particularly shown and described with reference to certain embodiments, it will be understood 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. | An improved device for simultaneously unrolling geotextile fabric and dispensing an aggregate layer for road construction comprises a hanger bar coupled to a vehicle frame. The hanger bar supports a roller bar adapted to carry a fabric roll. A dragger couples the hanger bar and arranges to present a dead-weight member on top of the fabric. An improved method using the improved device drags the chain on top of the fabric as it unrolls, thus holding the fabric in place. At the same time, a conveyered aggregate delivery system dispenses gravel on top of the fabric. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority under 35 U.S.C. 119(e) of U.S. provisional application no. 60/525,138 filed Nov. 28, 2003.
BACKGROUND OF THE INVENTION
[0002] Gastrointestinal motility control is of interest to medical practitioners, including to treat disorders of the gastrointestinal tract and to treat conditions related to the function of the gastrointestinal tract such as obesity. Previous patents have described various stimulation techniques for entraining or stimulating gastrointestinal motility, but these methods enhance or manipulate the spontaneously existing gastrointestinal electrical activity, thus hoping to indirectly affect gastrointestinal motility, since spontaneously existing motility can be regarded as a result of the existing electrical slow waves. In our previous patents and in the published research that followed, we suggested a third method for stimulation using sequentially administered trains of high frequency (50-500 Hz) voltages.
SUMMARY OF THE INVENTION
[0003] In the present application we provide according to an aspect of the invention a method and apparatus for overriding the spontaneously existing gastrointestinal (GI) motility and producing artificial peristalsis completely asynchronously with the spontaneously existing mechanical phenomena in the GI tract, in a given GI organ, or in a portion thereof, using trains of external voltages with wide range of frequencies (5-50,000 Hz), wide range of duty cycles (10-100%) and wide range of amplitudes (3-30V peak-to-peak). In a further aspect of the invention, we provide a method and apparatus for producing preliminary externally controlled contractions in the sphincter region or regions of the said GI organ or in a portion of it (for example, the pylorus in the stomach). The adjacent acetylcholine (ACh) patches in the vicinity of the said sphincter region are exhausted due to the prolonged invoked contractions, so that the sphincter inevitably relaxes as a result. In a still further aspect of the invention, we provide a method and apparatus that invokes externally controlled GI peristalsis after this sphincter relaxation is achieved, so that content is propelled through the said sphincter. And in a further aspect of the invention, we describe an implantable microsystem device which can achieve the described functionalities, which is either autonomously or transcutaneously powered. In addition, there is provided a way to disturb spontaneously existing peristalsis, or to completely or partially override it so that the process of spontaneous GI motility is asynchronously adversely affected as an avenue to treat morbid obesity, which can make use of the same device.
[0004] Further description of the invention is contained in the detailed disclosure and claims that follow.
BRIEF DESCRIPTION OF THE FIGURES
[0005] There will now be described preferred embodiments of the invention, with reference to the drawings, by way of illustration only and not with the intention of limiting the scope of the invention, in which like numerals denote like elements and in which:
[0006] FIGS. 1A-1D show placing of electrodes on portions of the gastrointestinal tract according to the invention;
[0007] FIGS. 2A-2C show a configuration of synchronized patches of external signals: sequential (A), overlapping (B) and embedded (C);
[0008] FIGS. 3A-3D and 4 A- 4 D are three dimensional views showing respectively the effect of the sequential and embedded excitation patterns on the stomach;
[0009] FIGS. 5A-5C show exemplary external signal patterns for producing reversed peristalsis;
[0010] FIGS. 6A-6D are three dimensional views showing effect of a sequential pattern of excitatory signals on the stomach;
[0011] FIG. 7 illustrates a single session of a sample pattern to invoke asynchronous contractile desynchronization;
[0012] FIGS. 8A-8B depict contractions resulting from the excitation pattern of FIG. 7 in a three-dimensional mathematical model of the stomach;
[0013] FIG. 9A shows the cyclic nature of the smooth muscle response to external neural electrical control assessed with implanted force transducers in the vicinity of the electrodes;
[0014] FIG. 9B is a detail of a cycle from FIG. 9A ;
[0015] FIGS. 10 and 10B show electrode configurations for invoked peristalsis of a stomach;
[0016] FIGS. 11A and 11B show excitation patterns for excitation of the corresponding electrode sets 1 , 2 , 3 in FIGS. 10A and 10B respectively;
[0017] FIG. 12 is a perspective view, with an inset showing an internal detail, of apparatus for carrying out the invention;
[0018] FIG. 13 shows schematically an arrangement for delivering excitation pulses without transcutaneous wires; and
[0019] FIGS. 14A and 14B are block diagrams of apparatus for carrying out the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] In this patent document, “comprising” means “including” and does not exclude other elements being present. In addition, a reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the elements is present. A reference to an element is not restricted to the particular form of the element disclosed, but includes functional equivalents now known or hereafter developed.
[0021] Electrodes for obtaining control of gastrointestinal tract motility are implanted either from the serosal or the mucosal side of the particular gastrointestinal organ (e.g. the stomach, the colon, the esophagus, etc.), and their axes could be either collinear or perpendicular to the organ axis. The electrodes are implanted in pairs. Each electrode pair consists of two electrodes, one being a ground (reference) and the other the active electrode. One or several electrode pairs (depending on the circumference of the organ in the area where the electrodes are implanted) form a local electrode set, which is implanted corresponding to an imaginary line perpendicular to the organ axis. One or several local electrode sets can be implanted along the axis of the gastrointestinal organ, either from the mucosal or from the serosal side.
[0022] FIGS. 1A-1D show sample electrode configurations for the stomach (A, B and C) and for a segment of the colon (D). Electrodes 10 can be collinear with the organ axis (A, B, D), or perpendicular to it (C). The length of the electrodes is between 0.2 and 5 cm. The distance between electrode sets can be between 1.5 and 10 cm. Electrodes from a given pair and from adjacent sets should not touch, and the minimal distance between them should be 1 cm. The electrodes can be implanted subserosally (A, D, C) or from the mucosal side (B). Electrodes implanted on the posterior wall of the organ are lighter in color. The electrodes of a given set are arranged correspondingly to imaginary lines perpendicular to the organ axis (shown in lighter color as well).
[0023] External signals are supplied to the electrodes 10 to achieve gastrointestinal motility control. The external signals supplied to the electrode sets, although synchronized between themselves, are completely asynchronous with the spontaneously existing motility in the particular GI organ, and override it, rather than stimulating or enhancing it in any way. The frequency of the synchronized signals ranges from 5 to 50,000 Hz, and their amplitudes range from 3V peak-to-peak to 30V peak-to-peak. The duty cycle can vary from 10 to 100%, for example 50% to 90%. The synchronized signals are delivered in patches with three basic configurations, sequential, overlapping, and embedded, and the pause between the patches or bursts ranges from 3 seconds to 3 minutes in a single session ( FIGS. 2A-2C ). Multiple sessions can be administered. The current delivery capability of the microsystem can be estimated considering the average total current consumption per unit muscular thickness of GI tissue per electrode pair, which is approximated as 3 mA/mm. With the assumption that the thickness of the muscle is in the range of 2.5 mm to 3.5 mm, the average total current drawn by the tissue will be in the range of 7.5 mA to 10.5 mA.
[0024] FIGS. 2A-2C show a configuration of the synchronized patches of external signals: sequential (A), overlapping (B) and embedded (C). Each invoked motility session can last from 3 seconds to 3 minutes. The time T 3 represents the composite duration of the external signals from all channels. This time, combined with an appropriate relaxation time (post-motility pause), constitute the overall invoked motility session time. The relaxation time is at least 2 times longer that the composite duration of the external signals in all channels, so that a complete relaxation of the smooth muscles can be achieved. The pause between successive patches in the sequential pattern (A) can be from 0 seconds to the duration of the patch itself, Ts 1 . The time between the end of Ts 1 in the proximal channel and the start of the signal patch in the next more distal channel is Ts 2 . The shift time To 2 in the overlapping pattern can be in the range between To 1 and To 1 -T, where T is the period of the high-frequency pulses (T=1/f, f=5 to 50,000 Hz) and To 1 is the duration of the external signal in channel 1 . The delay time Te 2 in the embedded pattern can be from Te 1 -T to Te 1 / 2 , where Te 1 is the duration of the external signal in channel 1 (which in this pattern coincides with the overall duration of the motility control session). The amplitude V of the stimuli can be in the range of 3-30V (peak-to-peak). The sequential pattern of FIG. 2A is illustrated in FIGS. 3A-3D , and the embedded pattern of FIG. 2C is illustrated in FIGS. 4A-4D , using a three-dimensional model of the stomach. Extensive tests have been performed on 8 acute dogs and the anticipated contractile response resulting from the production of invoked peristalsis was verified both visually and with force transducers implanted in the vicinity of the implanted electrode sets.
[0025] Invoked peristalsis using synchronized local contractions can be produced also in the opposite direction, a concept that could be labeled invoked reversed peristalsis. This opportunity could be very important for the treatment of morbid obesity, since reversed peristalsis can delay gastric emptying and affect in a controlled way the desire of a given patient to consume food. Similarly to the invoked distal peristalsis, three different patterns of the external synchronized patches can be employed. FIGS. 5A-5C represent various external signal patterns for producing reversed peristalsis. Since the microsystem producing the patterns is programmable, comfort levels specific to a given patient can be determined in order to produce the desired controlled peristalsis without inducing nausea and vomiting which are usual side effects of abnormal gastric motor function. FIGS. 5A-5C show sequential (A), overlapping (B) and embedded (C) synchronized patches of external signals aiming at producing reversed peristalsis. Each invoked motility session can last from 3 seconds to 3 minutes and the strength of the contractions is completely controllable by the microsystem, so that appropriate voltage treshholds can be selected in order to avoid invoked nausea and vomiting in the patient. The time T 3 represents the composite duration of the external signals from all channels. This time, combined with an appropriate relaxation time (post-motility pause), constitute the overall invoked motility session time aiming at producing reversed peristalsis. The relaxation time is at least 2 times longer that the composite duration of the external signals in all channels, so that a complete relaxation of the smooth muscles can be achieved. The pause between successive patches in the sequential pattern (A) can be from 0 seconds to the duration of the patch itself, Ts 1 . The time between the end of Ts 1 in the distal channel and the start of the signal patch in the next more proximal channel is Ts 2 . The shift time To 2 in the overlapping pattern can be in the range between To 1 and To 1 -T, where T is the period of the high-frequency pulses (T=1/f, f=5 to 50,000 Hz) and To 1 is the duration of the external signal in the most distal channel 4 . The delay time Te 2 in the embedded pattern can be from Te 1 -T to Te 1 / 2 , where Te 1 is the duration of the external signal in the most distal channel 4 (which in this pattern coincides with the overall duration of the motility control session). The amplitude V of the stimuli can be in the range of 3-30V (peak-to-peak). The sequential patterns from FIG. 5A are illustrated in FIGS. 6A-6D . It should also be mentioned that inducing controlled reversed peristalsis in the antrum affects the mechanoreceptors, which are abundant in the area, if appropriate voltage levels for the external signals are utilized. Thus, rather than inducing nausea and vomiting, a perception of early satiety could result. This, by itself, could be a substantial avenue for treating morbid obesity.
[0026] Rather than producing reversed peristalsis, gastric content can be retained in the stomach simply by invoking controlled asynchronous contractile desynchronization. Similarly to the invoked peristalsis patterns described above, this technique also overrides the spontaneously existing contractile pattern in the stomach, but imposing a pattern which aims not to move content distally (normal forward persitalsis), nor to move it in a proximal direction (reversed peristalsis) in a synchronized fashion, but to keep the content in prolonged contact with the antral mechanoreceptors simply by “shaking it” back and forth, thus inducing in the patient a perception of early satiety. This can be achieved by the repetitive asynchronous administration of the external voltage signals controlling minimized number of implanted electrode sets (two sets could be sufficient, one proximal and one distal). FIG. 7 illustrates single session of a sample pattern to invoke asynchronous contractile desynchronization, and FIGS. 8A-8B depict the resulting contractions in a three-dimensional mathematical model of the stomach, which was verified experimentally in acute tests. The session can be repeated in random sequence to prolong the “shaking” effect.
[0027] For sphincter control, a pair of electrodes is implanted on or in the vicinity of the sphincters of the organ (for example, on the pylorus of the stomach) so that the sphincters can be controlled (brought into a contracted stage to prevent content passing, or forced into relaxation to permit content passing) by utilizing or exhausting the available acetylcholine (ACh) patches in the vicinity of the said sphincters. These patches are released as a result of prolonged exposure to high frequency pulse trains, and the timing of this release, as well as the time it takes to exhaust these patches are known to us from extensive experimental work ( FIGS. 9A , 9 B). FIG. 9A shows the cyclic nature of the smooth muscle response to external neural electrical control assessed with implanted force transducers in the vicinity of the electrodes. Prolonged motility control session clearly reveals the cycles of sustained contractions followed by relaxations, although the continuous external electrical control was maintained ( FIG. 9A ). Within about 25-30 seconds the ACh patches in the vicinity of the muscle (e.g. the pylorus) get exhausted and the muscle relaxes even though the external electrical control continues. These timings are illustrated in details in FIG. 9B , which can be regarded as a zoomed-in averaged cycle extracted from FIG. 9A .
[0028] Specifically, the timings for achieving forced pyloric relaxation have been measured in large dogs by implanting force transducer in the vicinity of the pylorus, and utilizing pyloric electrode configurations depicted in FIGS. 10A-10B with the excitation scheme shown in FIGS. 11A and 11B respectively. If, for example, a relaxation of the pylorus is required to propel content, continuous externally invoked and controlled contraction of this sphincter takes place until the ACh patches in its vicinity are exhausted, and the pylorus relaxes while the ACh patches recover. During this period of induced relaxation, the content is propelled using a synchronously produced invoked peristalsis under microprocessor control. Since the relaxation of the pylorus is also invoked under microprocessor control, the invoked peristalsis and the pyloric relaxation can be completely synchronized for maximally efficient gastric emptying.
[0029] Alternatively, knowing for how long the pylorus can be kept contracted, and how often its cyclic contractions can be invoked, gastric emptying could be significantly slowed down in particular time intervals during or after food intake. In addition, pyloric control during fasting periods can be utilized to manipulate the feelings of hunger or satiety by interrupting the spontaneously-existing migrating myoelectrical complex in the stomach, again under microprocessor control and without synchronizing this activity with the spontaneously existing motility but by overriding it asynchronously.
[0030] FIGS. 11A and 11B show an example of synchronizing preliminary pyloric contraction for the purpose of exhausting the ACh patches in the vicinity of the pylorus using electrode set 1 with the contractions produced using two other electrode sets (proximal, 2 and distal, 3 ). The region of the stomach subject to invoked peristalsis is shown darker. Electrode configurations can be perpendicular to the gastric axis ( FIG. 10A ), or collinear with it ( FIG. 10B ). The electrode set 1 , implanted in the pyloric region, delivers external voltage trains for the time Tpr needed to exhaust the ACh patches in the vicinity of the pylorus (about 25-30 seconds), resulting in pyloric relaxation at the very end of this time period. About half way through Tpr (e.g. around the 10 th -15 th second), the delivery of external voltage pulses to the proximal electrode set starts, and after Tpr, the delivery of external voltage pulses to the distal electrode set takes place ( FIG. 11A ). Alternatively, the delivery of external voltage trains can continue with the pyloric electrode set 1 for the entire session, since the pylorus will relax after Tpr in a cyclic fashion anyway ( FIG. 11B ). The latter technique provides a prolonged, albeit cyclic, pyloric relaxation, but inevitably is related to higher power consumption.
[0031] Apparatus for carrying out the invention is shown in FIGS. 12 , 13 , 14 A and 14 B. The power supply of the proposed implantable microsystem can be achieved either by (a) autonomous battery; (b) autonomous battery which is rechargeable through a transcutaneous inductive link facilitated by an abdominal belt periodically worn by the patient (preferably during sleep) ( FIG. 12 ); or (c) transcutaneous power transfer facilitated by an abdominal belt worn by the patient during the periods of the desired gastrointestinal organ control ( FIG. 13 ).
[0032] FIG. 12 shows a distributed microsystem setup. The external control is administered via abdominal belt (left), in which the transmitting inductive coil for transcutaneous power transfer is positioned ( 1 ), along with the associated microcontroller-based electronics (2, see also FIGS. 13 and 14 B). The belt is attached to the body in the abdominal area ( 3 ). The implanted microsystem (right) is sutured on the inner side of the abdominal wall right under the abdominal bell center. It contains receiving coil ( 4 ) which is aligned with the transmitting coil and microcontroller-based electronics ( 5 , see also FIG. 14A ). In case of autonomous non-rechargeable battery-based power supply for the implanted microsystem, transmitting and receiving coils are not necessary and the dimensions of both Microsystems could be reduced. The implanted microsystem is shown with four channels, and the pyloric channel is connected to the schematic replica of the stomach of FIG. 1B .
[0033] FIG. 13 depicts an external transmitter 20 located over the skin 22 in the abdominal belt worn by the patient can be utilized to power one or multiple implants 24 in various sections of the gut 26 (e.g. in the colon). The transcutaneous power supply link is inductor-based.
[0034] The overall block diagrams of the entire system are presented in FIGS. 14A and 14B . Both the implantable device and the external controlling device are Microsystems, each including a microcontroller. FIGS. 14A and 14B show block diagrams of the implantable device ( FIG. 14A ) and the controlling device located in the abdominal belt in a discrete electronic implementation. Very-Large-Scale-Integration (VLSI) of the same concept is also possible and could be preferred if further device miniaturization is desired. In this particular implementation the battery 32 of the implantable device can be autonomous or externally rechargeable. The communication between the controlling microsystem of FIG. 14B and the implant of FIG. 14A is provided with radio-frequency tranceivers.
[0035] The system includes an external control circuitry and an implantable device. Once the implant is in place, the external control circuitry can be utilized to control the motility control parameters, the number of motility control sessions and the pause between successive sessions. The implantable microsystem of FIG. 14A includes five major blocks: (1) microcontroller 30 ; (2) DC-DC converters 34 ; (3) MOSFETs 36 ; (4) analog electronic switch 38 ; and (5) wireless transmitter 40 and receiver 42 (see FIG. 14A ). The microcontroller 30 may be for example model AT90S2313(Atmel, San Jose, Calif.) programmed to generate the digital motility control pulses and to control the output of the DC-DC conversion stage. In addition, it determines the duration of each motility control session and the overlap between successive channels via the analog switch 38 . The motility control parameters (amplitude, frequency, overlap, and session length) can vary from one motility control session to another. The microcontroller 30 is pre-programmed with a set of different values for each motility control parameter. In addition, a default value is specified for each parameter. The operator can choose the desired value of each parameter from this pre-determined list using a transcutaneous control link. The clock frequency for the microcontroller 30 has been chosen to be 20 KHz. This low crystal frequency was chosen to minimize the switching power losses in the microcontroller 30 . The maximum frequency will be 500 Hz, resulting in a minimum pulse width of 2 ms. A 20 KHz crystal has an instruction cycle of 50μs, which is sufficiently large for generating 2 ms or slower pulses.
[0036] The RF receiver 40 , for example a MAX1473(Maxim, Dallas, Tex.), is used to receive serial wireless data containing the choice of the motility control parameters from the external portable control unit of FIG. 14B . This data is transmitted serially and in an asynchronous mode to the microcontroller 30 using the UART input. The data transfer rate (baud rate) is set to 125 bit/s for operation with a crystal frequency of 20 KHz. The microcontroller 30 will sample the data at 16 times the baud rate. If the UART input does not detect a start bit for data transfer in the first 5 seconds after power-up, the microcontroller 30 will start a motility control session using its default parameters. The microcontroller 30 will send a ‘confirmation byte’ at the onset of the control pattern (5 s after startup) to the external control circuit via the RF transmitter. A byte with all one bits represents the onset of motility control with new parameters, while a byte with all zeros represents the onset of motility control with default parameters. The DC-DC conversion block 34 includes two integrated circuits (ICs): LT1317(Linear Technology, Milpitas, Calif.), a step-up voltage converter, and TC7662B (Microchip, Chandler, Ariz.), a charge-pump voltage inverter. These two ICs convert the supplied 3V to the desired amplitude (V stim ). V stim is in the range of ±5V to ±10V and can be adjusted by the microcontroller 30 . The MOSFET stage 36 utilizes for example two logic transistors FDV303N and FDV304P (Fairchild, South Portland, Me.) and two power transistors, which are included in one package IRF7105 (International Rectifier, El Segundo, Calif.). The logic FETs 36 have a low gate threshold voltage and can be switched by the 3V logic square wave produced by the microcontroller 30 . These logic transistors drive the gates of the power FETs, which convert the digital square wave to a bipolar analog output of the same frequency and an amplitude equal to V stim . The output of the transistors 36 is directed to the stimulating electrodes 10 through a four-channel analog switch 38 (for example ADG202, Analog Devices, Norwood, Mass.). Each of the four switch channels closes upon receiving an enable command from the microcontroller 30 . The analog switch 38 also isolates each electrode 10 from the successive electrode sets. The microcontroller 30 preferably receives both the necessary electrical power and the required stimulation pattern information transcutaneously through the receiver 40 , optionally also using an inductive coil as part of the receiver 40 . The microcontroller 30 then converts the obtained stimulation pattern information into real stimulation sequences delivered to the implanted electrodes by controlling operation of the logic FETs 36 . On conclusion of the sending of a stimulation sequence, the microcontroller 30 then reports back to an external controller the success or failure of the delivered stimulation sequences. Success or failure may be determined for example by sensors that detect whether a specified contraction has taken place and send a corresponding signal to the microcontroller 30 .
[0037] A portable microcontroller-based controller circuit allows the user to select the appropriate parameters for producing artificially invoked peristalsis (frequency, amplitude, overlap between channels and session length). This battery-operated control circuit is external to the body, and is worn by the patient in an abdominal belt. A digital wireless transmitter 50 (MAX1472, Maxim, Dallas, Tex.) is used to transmit the chosen motility control parameters to the implanted motility control device ( FIG. 14A ). The external controller 52 can also be used to adjust the number of the successive motility control sessions ( 1 - 4 ) as well as the pause period between the successive sessions ( 30 - 120 s). The external circuit turns the implanted motility control device on or off for adjustable lengths of time by controlling a normally open magnetic reed switch 33 that is integrated in the implanted system. The reed switch 33 is placed in series with the implanted battery 32 . The controller 52 turns the magnetic reed switch 33 on by energizing a coil 54 to generate a static magnetic field. FIG. 14B shows the design of the external controller.
[0038] The external controller has a toggle switch 56 that allows the user to implement either a default motility control session (using the implanted motility control device's default parameters) or a new motility control session. The parameters for the new motility control session are downloaded to the external unit's microcontroller 52 from a PC 58 via an RS232 link. These parameters are transferred from the microcontroller 52 to the wireless transmitter 50 using the UART line, at a baud rate equal to the implanted circuit's baud rate of 125 bit/s. The wireless transmitter 50 then sends this information to the implanted circuit ( FIG. 14A ). In the case of motility control session with default parameters, the RF transmitter 50 will be disabled and the microcontroller 52 will not send any data to it. The microcontroller 52 will simply turn the implanted circuit on via the reed switch 33 . The implanted circuit of FIG. 14A will interpret lack of incoming information from the transcutaneous link as a sign that default motility control session must be performed. The RF receiver 60 is used for receiving the ‘confirmation byte’ from the implanted stimulator. The microcontroller 52 will send a signal to de-energize the coil t+5 seconds after startup, where t represents the time length of each motility control session.
[0039] The methods and apparatus disclosed here radically differ from previously proposed gastrointestinal stimulation techniques, at least since:
[0040] (a) it does not stimulate or enhance the spontaneously existing gastrointestinal electrical or mechanical activity, but rather overrides the latter and imposes motility patterns that are entirely externally controlled by an implantable microprocessor;
[0041] (b) calls for implantation of electrode sets (either from the serosal or from the mucosal side) around the circumference of the organ, but the electrode axes themselves could be collinear or perpendicular to the organ axis (see for example FIGS. 1A-1D );
[0042] (c) utilizes external signals with extended frequency and amplitude range, and with extended timing parameters depending on the desired application (see for example FIGS. 2A-2C , FIGS. 5A-5C and FIG. 7 );
[0043] (d) calls for synchronized sphincter control by exhausting the ACh patches in the vicinity of the organ with an appropriate timing (see for example FIGS. 9A , 9 b, 10 A, 10 B, 11 A and 11 B);
[0044] (e) induces forward or reversed peristalsis, or asynchronous contractile desynchronization with appropriate and programmable intensity so that the patient would not experience discomfort, pain, nausea or vomiting;
[0045] (f) suggests innovative and versatile power supply options using transcutaneous inductive link for battery recharging or for complete power transfer in the framework of an implantable microsystem (see for example FIGS. 12 , 13 ).
[0046] A number of inventions have been disclosed in this patent disclosure and it will be appreciated that not all features disclosed here form part of all of the inventions. The embodiments disclosed are exemplary of the inventions. | A method and a multichannel implantable device are described for partial or complete restoration of impaired gastrointestinal motility, or for disturbing and/or partially or completely blocking normal gastrointestinal motility using one or multiple microsystem-controlled channels of circumferentially arranged sets of two or more electrodes which provide externally-invoked synchronized electrical signals to the smooth muscles via the neural pathways. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of the prior filed, pending provisional application, Ser. No. 60/076,366, filed Feb. 27, 1998.
BACKGROUND OF THE INVENTION
The present invention relates to a method of knitting the selvage of a tubular knit fabric, and more particularly, a method of knitting the selvage on a double lock V-bed flat knitting machine without producing a raised seam.
Tubular or weft knit is produced on a V-bed flat knitting machine by knitting, row by row, a front sheet of fabric and a rear sheet of fabric and binding together the edges, or selvages to form a knitted fabric tube.
In knitting the selvage of a double lock tubular knit fabric with a flat knitting machine, it is known to knit the front needles when the yarn carrier is moving from right to left, and to knit the rear needles when the yarn carrier is moving from left to right. The conventional method of knitting the selvages leaves a raised seam on both the inside and the outside of the tube which makes the garment, especially close fitting garments such as socks, particularly prosthetic socks, uncomfortable to wear. Additionally, the conventional method of knitting the selvages leaves holes along the selvages further reducing the wearing comfort and the aesthetic appeal of the garment.
In another known method, the selvages are simply sewn together to form the tube. This creates a raised seam on the inside of the tube.
SUMMARY OF THE INVENTION
Accordingly, it is the primary object of the present invention to produce a knitted double lock selvage that does not have a ridge on one side of the fabric.
Additionally, it is another object of this invention to produce a knitted double lock selvage that has no holes.
These objects are achieved by the selective activation of the front and rear needles on each pass of the yarn carrier of the double lock machine. Such activation occurs at each selvage to produce a seam that has no ridge on the inside of the tubular garment, by controlling the idle and knitting states of each needle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of a V-bed flat machine showing front and rear needlebeds and needles in the idle position.
FIG. 2 is a cross sectional view of a V-bed flat machine showing needles in the knitting position.
FIG. 3 is a cross sectional view of a V-bed flat machine showing needles in the cast-off position.
FIG. 4 is a schematic view of first lock pass of right selvage showing front and rear needles idle, yarn carrier moving from left to right.
FIG. 5 is a schematic view of second lock pass of right selvage showing front needle idle and rear needle knitting, yarn carrier moving from left to right.
FIG. 6 is a schematic view of first lock pass of right selvage showing front needle knitting and rear needle idle, yarn carrier moving from right to left.
FIG. 7 is a schematic view of second lock pass of right selvage showing front needle knitting, yarn carrier moving from right to left.
FIG. 8 is a schematic view of second lock pass of right selvage showing rear needle knitting, yarn carrier moving from right to left. Completed right selvage knit pattern is shown.
FIG. 9 is prior art showing a conventional right selvage knit pattern.
FIG. 10 is a diagrammatic cross-sectional illustration of a completed tubular garment made in accordance with the method of the present invention.
DETAILED DESCRIPTION
A conventional V-bed flat machine, illustrated in FIGS. 1 and 2, is a latch needle machine in which front and rear opposed needlebeds 10 and 12 respectively, are arranged in an inverted "V" in the form of a 90 degree angle to each other and at a 45 degree angle to the horizontal. In addition to the front and rear opposed needlebeds 10 and 12, the machine's major components include its cams (not shown) which act on either the butts 14 of front and rear latch needles 16 and 18 respectively, or the butts of associated jacks, which in turn actuate the latch needles and a yarn carrier 20. On a double lock machine, the yarn carrier 20 includes two side-by-side locks, which feed the yarn 22 to the needles 16 and 18. As the yarn carrier 20 passes the needles as it travels back and forth, the needles are either idle or knitting. When idle, the yarn carrier passes without any needle action. When a needle is knitting, as the yarn carrier passes, the needle is activated by its associated cam, the needle receives the yarn, and casts off the previous stitch (FIG. 3). To form a tubular double lock garment (illustrated diagrammatically in FIG. 10), the yarn carrier moves back and forth along the needle beds transferring yarn to the needles in a set knitting pattern.
The needle activation for the conventional method of knitting the selvages is set forth in Table 1 below.
TABLE 1______________________________________Prior ArtYarn carrier Left RightDirection Lock Needles Selvage Selvage______________________________________Left to Right First Front Idle Idle Rear Knit Knit Second Front Idle Idle Rear Knit KnitRight to Left First Front Knit Knit Rear Idle Idle Second Front Knit Knit Rear Idle Idle______________________________________
As the yarn carrier moves from left to right, the first lock encounters the left selvage of the knitted garment. As the first lock then passes the left selvage, the front needle is idle and the rear needle knits. As the second lock passes the left selvage, the front is idle and the rear needle knits. As the first lock passes the right selvage, the front is idle and the rear needle knits. As the second lock passes the right selvage, the front needle is idle and the rear needle knits.
The yarn carrier then reverses direction and moves from right to left. As the carrier moves from right to left, the order of the locks is reversed. The first lock when moving from left to right is the second lock when moving from right to left. Likewise, the second lock when moving from left to right is the first lock when moving from right to left.
As the first lock encounters the right selvage, the front needle knits and the rear needle is idle. As the second lock passes the right selvage, the front needle knits and the rear needle is idle. As the first lock encounters the left selvage, the front needle knits and the rear needle is idle. As the second lock passes the left selvage, the front needle knits and the rear needle is idle. This process is repeated along the entire length of the garment.
A cross section of one cycle of the conventional selvage knit pattern for the right selvage is shown FIG. 9. The left selvage pattern is a mirror image of the right selvage pattern and therefore is not shown.
In the present invention, the needles are activated in accordance with Table 2 below.
TABLE 2______________________________________Present InventionYarn carrier Left RightDirection Lock Needles Selvage Selvage______________________________________Left to Right First Front Idle Idle Rear Knit Idle Second Front Knit Idle Rear Knit KnitRight to Left First Front Idle Knit Rear Idle Idle Second Front Idle Knit Rear Knit Knit______________________________________
As the yarn carrier moves from left to right, the first lock encounters the left selvage of the knitted garment. As the first lock then passes the left selvage, the front needle is idle and the rear needle knits. As the second lock passes the left selvage, both the front and rear needles are idle. As the first lock passes the right selvage, both the front and rear needles are idle (FIG. 5). As the second lock passes the right selvage, the front needle is idle and the rear needle knits (FIG. 6).
The yarn carrier then reverses direction and moves from right to left. Again, the order of the locks is reversed as described above. As the first lock encounters the right selvage, the front needle knits and the rear needle is idle (FIG. 7). As the second lock passes the right selvage, both the front and rear needles knit (FIG. 8). As the first lock encounters the left selvage, both the front and rear needles are idle. As the second lock passes the left selvage, the front needle knits and the rear needle is idle. This process is repeated along the entire length of the garment. The knit pattern of the left selvage is an inverted mirror image of the right selvage and therefore is not shown.
Using the method of the present invention, a double lock tubular knit fabric is formed (FIG. 10) in which a front sheet of fabric 30 and a rear sheet of fabric 32 are bound together at the left selvage 34 and the right selvage 36. Selvages 34 and 36 formed as described above, each provide a seam that is smooth on the inside and raised on the outside of the tube without holes, thus improving the wearing comfort and aesthetic appeal of the garment. | A method of knitting an improved comfort selvage on a V-bed flat knitting machine by manipulating the front and rear needles independently at the selvages. By using an asymmetrical knitting pattern at the selvage, a knitted double-lock selvage is produced that has no ridge on one side of the fabric or holes, thus improving the wearing comfort and aesthetic appeal of the garment. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to handcuffs or similar-type restraints, and more specifically to an apparatus that enables an arresting officer to separately apply each restraint to each wrist of a resisting arrestee, regardless of the position or location of each wrist, and further allows the arresting officer to bring each restraint together, thereby joining the arrestee's wrists effectively to each other at the same time.
2. Preliminary Discussion
It is often the case that a criminal "takedown", or physical overpowering of a resisting miscreant pursuant to an arrest, will require three, four and sometimes five police officers to effect the application of a set of handcuffs to a single arrestee. Since conventional handcuff bracelets are connected by approximately one inch of chain, arresting officers must effectively join, or bring together, the suspect's arms in order to secure both wrists together prior to the application of such handcuffs.
A resisting arrestee, who is young and strong, can make it virtually impossible for just two officers to properly apply a pair of conventional handcuffs, especially if the officers are not as powerful as the resisting arrestee or just out of shape. As a result, one or more of the arresting officers would have to step up to a higher level of force, i.e. pepper spray or baton, and with every increase in force, there exists the increased potential for injury or liability of the officers and/or injury, and sometimes further liability, of the arrestee.
Even with additional "backup," it seldom, if ever, provides a favorable impression, or "looks good" to see three or more officers on top of a single unarmed arrestee, especially since the nature of the takedown is often hidden from view by the bodies of the arresting officers. Such a scene has often incited uninvolved observers to become sympathetic to the arrestee and even to interfere with the arrest. Of course, the most popular bystander response in today's age of cop shows and helicopter reporting is to try and capture the incident on film, which can make a bad situation look even more incriminating, especially if the officer's application of force is perceived as unjustified in the public eye.
The problem of restraining a resisting arrestee, or restrainee, is especially dangerous in a prison setting, where corrections officers are usually in the minority and must be self-sufficient in a world of aggressively dangerous individuals, many or most of whom have complete contempt for law and authority in general. For example, in a prison setting, corrections officers often experience wild, unanticipated bursts of energy from a restrainee after the application of a single cuff to only one of the restrainee's wrists. This creates an immediate and dangerous situation for the restraining officer, because at this point the handcuffs now become a weapon for the prisoner. It is often the case that as the stimulated prisoner swings with arms flailing wildly at the restraining officers, the unattached restraint, or "bracelets," strikes and splits open noses, cheeks and eyes, resulting in a serious injury or even a potentially fatal situation in the absence of appropriate backup.
It takes an enormous amount of upper body strength to apply standard or conventional handcuffs, especially since the arresting officers must accomplish two difficult feats at once. First, the officer must restrain and immobilize the arrestee. Second, the officer must force the arrestee's arms close enough together so that both wrists can be handcuffed at the same time. Not only do these two actions work against each other, but an arrestee can often use the officer's own strength and force against him. For example, as the officer is forcefully manipulating the arm or arms of an arrestee, it is often the case that an arrestee will suddenly relinquish all resistance and pull away in the same direction that the officer is pushing, thereby allowing the arrestee to break loose from restrainers.
It is no wonder that arresting officers are often winded and justifiably disturbed after such an encounter. In fact, the constant scuffles and dangerous encounters create a highly precarious and unstable environment for arresting officers, and deficiencies in conventional restraining devices tend to make bad situations even worse.
The present inventor, after considerable on-the-job experience with deficient and ineffective restraining devices, has devised an apparatus that overcomes many, if not all, of the deficiencies of conventional handcuffs by enabling an arresting officer to apply a pair of handcuffs in an efficient manner without first expending a great deal of energy in bringing the arrestee's arms together. The apparatus of the present invention streamlines the conventional handcuffing process by allowing an officer to apply each handcuff separately without first having to join the arrestee's arms. Once each handcuff is attached, the apparatus of the present invention enables the arresting officer to forcefully join the arrestee's arms together to assume the conventional handcuffed stance or position. The joinder of the wrist restraints is preferably accomplished through the use of a ratcheting mechanism, similar in design to a fishing reel, to which each restraint is integrally connected. Such mechanism allows the arresting officer to, in effect, "reel in" each restraint until such restraints are brought together in a close relationship. The apparatus of the present invention, therefore, provides a much more effective solution to the problems plaguing conventional handcuff-type devices and creates a safer environment for both the arresting officer and the resisting detainee.
DESCRIPTION OF RELATED ART
The prior art has failed to effectively address the above-stated deficiencies in conventional handcuffs. The evolution of the prior art appears to have focused on the modernization of the handcuff device as a unit, not necessarily on the problems underlying its everyday use. For example, where handcuffs have conventionally been fashioned out of metal, involving complex mechanical structures and key-type release mechanisms, today's handcuffs often comprise disposable, self-locking plastic ties of the type used to bind bundles of wires and the like. Such ties are undoubtedly cheaper to manufacture, and are often useful when the detained individual poses no threat to the safety of the officer, such as may be the case when such individual needs to be temporarily bound during transport to and from the prison or the like. However, simple plastic ties and the like, which are often applied with the cooperation of the detainee, are woefully inadequate in dangerous and risky situations, especially where it is nearly impossible to prepare the detainee's wrist for the proper application of such ties. Some of the prior art references in the handcuff field are described below.
U.S. Pat. No. 1,534,936 issued to E. E. Fischbach on Apr. 21, 1925, entitled "Confining and Restraining Device," discloses the use of separate, yet joinable and lockable, strap devices for the quick restraint of an individual. Finger rings at the ends of a strap accommodate a single finger on the detainor's hands thereby allowing the detainor to grasp, with the remaining fingers, the lockable joining means near the finger rings. The detainor is then required to wrap the strap, by hugging or the like, around the detainee or and quickly bring together the joining means, and after the strap is joined and locked, the detainor pulls outwardly on the finger rings to further tighten the strap. The detainor may then quickly and easily release his or her hands from the finger rings.
U.S. Pat. No. 4,024,736 issued to W. P. DeMichieli on May 24, 1977, entitled "Prisoner Restrainer," discloses a strap rewind reel connected between two ankle cuffs that allows a detainee to walk with a predetermined stride while cuffed. The reel unwinds the strap as the detainee's legs are spread apart, and winds-in the strap as the legs are brought together. A lock inside the wheel activates if the strap unwinds at an excessive rate thereby preventing the detained from assuming a running stride.
U.S. Pat. No. 4,909,051 issued to J. A Lee on Mar. 20, 1990, entitled "Keeper Plate for Strap Handcuffs," discloses a plate which reduces the danger of restricting the detainee's circulation by providing a flattened concave edge that is thicker than the restraining strap.
U.S. Pat. No. 5,099,662 issued to B. Tsai on Mar. 31, 1992, entitled "Contractible Handcuff," discloses an extendible, slotted metal band which automatically encircles and binds any object it touches or contacts, including, but not limited to, a human wrist or an unreachable object. A motor in the handle controls the direction, i.e. extension or retraction, of the metal band, while a hook-like section at the end of the band cooperates with slots in the body of the band to lock and restrain the band around or about an object.
U.S. Pat. No. 5,443,155 issued to E. Robinson on Aug. 22, 1995, entitled "Wrist Restraining Device," discloses a dual system of wrist loops that simultaneously tighten with the pull of a U-shaped bight strap section formed by the positioning of the strap, such bight section also doubling as a handle. The handle section allows the detainor to maneuver the wrist strap assembly while maintaining a safe distance from the detainee's bound, and potentially dangerous, hands.
U.S. Pat. No. 5,651,376 issued to G. Thompson on Jul. 29, 1997, entitled "Flexible Dual Loop Restraining Device" discloses a plastic strap, dual-loop restraint system employing a different tightening orientation or arrangement from those previously mentioned. The Thompson reference stresses the one-way adjustability and simplicity of the structure, noting that not all detainees require the same strap tightness.
The present inventor, after years of personal experience, has determined a need for a restraining system that is more efficient, practical and safer for all individuals involved, as compared with conventional restraining systems of the prior art or currently represented in the marketplace. The prior art is devoid of any references or representations that satisfy those particular, everyday needs addressed by the present inventor and/or his apparatus in accordance with the present invention. It is an undeniable fact that crime will always be a part of our everyday lives. Anything that improves the transition for the criminals and law enforcers during the capture phase, which provides a safer environment for all, should be welcomed with "open arms," and the apparatus of the present invention is, in fact, specifically designed to alleviate the difficulty of capturing or immobilizing those individuals who in fact provide law enforcers with "open arms."
OBJECTS OF THE INVENTION
It is an object of the present invention, therefore, to provide a restraining device that enables law enforcement officials to easily and more efficiently control and handcuff a resisting arrestee.
It is a further object of the present invention to provide a restraining device that enables a resisting arrestee to be apprehended with the least number of law enforcement officials necessary.
It is a still further object of the present invention to provide a restraining device that may be applied to a resisting arrestee regardless of the position of each of the arrestee's appendages, or limbs.
It is a still further object of the present invention to provide a restraining device that, once applied to the arrestee's appendages, or limbs, allows law enforcement officials to join or unite such appendages to a more manageable position.
It is a still further object of the present invention to provide a restraining device that uses a reel and ratchet mechanism to effect the joinder of the handcuffs or manacles of the device of the invention.
It is a still further object of the present invention to provide a restraining device that may be attached or connected to a location adjacent the law enforcement official's body for easy storage, access and implementation.
It is a still further object of the present invention to provide a restraining device that is simple to use and more efficient than conventional handcuff devices.
Still other objects and advantages of the invention will become clear upon review of the following detailed description in conjunction with the appended drawings.
SUMMARY OF THE INVENTION
The apparatus of the present invention comprises a pair of handcuff members, each connected to a housing assembly by way of elongated cable sections. These cable sections are attached at their other ends to a rotatable spool that is sturdily housed within a box ratchet assembly. The elongated cables replace a conventional, short chain piece that normally spans one inch between conventional handcuffs. Such cables are reeled onto the spool member with a ratcheting motion, enabling the law enforcement officer to maintain a controlled joinder of the handcuffs and the arrestee's wrists, while a release mechanism enables a law enforcement official to lengthen the distance between the handcuffs and the housing assembly, thereby lengthening the distance between the separate handcuffs in preparation for their efficient application.
To operate the apparatus of the present invention, each handcuff is separately applied to each of the wrists of the resisting arrestee taking advantage of the increased distance between the handcuff pieces provided by the elongated cable sections. Once the handcuffs are applied, the law enforcement officer or detainer joins the arrestee's wrists by advancing the ratchet mechanism and reeling the handcuff cable sections into the housing assembly. By using the apparatus of the present invention, the officer is not initially required to join the arrestee's wrists, frequently a feat onto itself, prior to applying the handcuffs. This facilitates a reduced law enforcement presence at the crime scene and establishes a safer environment for all persons involved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an overall, or top view of the restraining device of the present invention.
FIG. 2 is an enlarged, side view of the housing assembly of the restraining device of the present invention.
FIG. 2A is a top view of an alternative embodiment of the restraining device of the present invention.
FIG. 3 is a side view of an anchoring implement used in connection with the device of the invention.
FIG. 4 is a top view of the anchoring implement of FIG. 3.
FIG. 5 is a diagrammatic view of a detainee in a prone position for purposes of illustrating the application of the anchoring implement of FIGS. 3 and 4.
FIG. 6 is a diagrammatic view of a detainee in a prone position for purposes of illustrating an alternative embodiment of an anchoring implement used in connection with the device of the present invention.
FIGS. 7 and 8 are overall, or top, views of an arrestee in the prone position for purposes of illustrating the use of the device of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following detailed description is of the best mode or modes of the invention presently contemplated. Such description is not intended to be understood in a limiting sense, but to be an example of the invention presented solely for illustration thereof, and by reference to which in connection with the following description and the accompanying drawings one skilled in the art may be advised of the advantages and construction of the invention.
FIG. 1 is an overall, or top view, and FIG. 2 is an enlarged, side view, of the restraining device of the present invention comprising a pair of clasping members or cuffs 100 and 150 (not shown in FIG. 2) each connected to a housing assembly 300 by flexible coupling members or cables 200 and 250 respectively, each cable shown partially in phantom. For purposes of this description, cuffs 100 and 150 will be described as handcuffs for conventional placement about an arrestee's wrists, although the apparatus of the present invention could be applied to other appendages such as an arrestee's ankles or the like. As will be understood, the device of the invention is particularly useful in the case of a resisting arrestee. The housing assembly 300 comprises an outer casing 400, a spool member 500, shown in phantom in FIG. 1 and in full in FIG. 2, a ratchet handle 600 having a ratchet connector 630 and a ratchet release 660. Ratchet handle 600 is preferably of a suitable thickness so that it may be easily and firmly grasped in the palm of a user's hand. The handle 600 may, however, also have a further handle extension 610 for gripping engagement in a vertical plane, shown more clearly in FIG. 2. While such handle extension 610 is optional, it is shown herewith for purposes of illustration. There is also an attachment member 700 connected to the housing assembly 300 having attachment means 750, preferably in the form of a snap, clip or the like, positioned on the end thereof. The attachment member 700 cooperates with an anchoring implement, such anchoring implement shown and described in connection with FIGS. 3 through 6. Cuffs 100 and 150 are shown in FIG. 1 extended away from the housing member 300 with cables 200 and 250 in an outstretched position. Cables 200 and 250 are wound about the spool member 500, or reeled into the housing assembly 300, with the ratcheting handle 600, until the handcuffs 100 and 150 are brought together in close proximity. The elongated cables 200 and 250 allow a user of the apparatus of the present invention, preferably a law enforcement official, to manipulate each handcuff separately and at considerable distance from each other during the apprehension of a resisting arrestee.
The handcuffs 100 and 150 are preferably of the conventional, clasping type having locking means 110 and 160 as shown. The handcuffs 100 and 150 are designed for separate application to each of the arrestee's wrists, without the necessity for pre-joinder of the wrists. The cables 200 and 250 are each preferably approximately two feet long and constructed from steel, for example, one-eighth inch diameter cable. The length, diameter and material composition of the cables 200 and 250 could vary with the circumstances, as long as the length is sufficient to apply the handcuffs 100 and 150 to each wrist of a resisting arrestee respectively even while such wrists are not necessarily conveniently positioned together prior to clasping. The diameter and material composition of the cables should be great enough to withstand even the most unruly resisting arrestee, since it would be hazardous to have the cables snap or break during the act of capture or thereafter. With two-foot cable lengths in their fully outstretched position, the handcuffs of the invention can effectively and efficiently be applied if the resisting arrestee wrists are approximately four feet apart, which is a considerable advantage over conventional handcuffs that are usually separated by a relatively measly one inch chain.
The housing assembly 300, more clearly shown in FIG. 2, comprises a ratchet handle 600 which enables the user or law enforcement official (not shown) to wind or rotate the spool 500 thereby reeling in the cable members 200 and 250 onto the shaft 550, which effectively brings the handcuffs 100 and 150, shown in FIG. 1, closer together. A ratchet mechanism as is generally known to those skilled in the art is built into the handle 600 and connector 630 such that the rotation of the shaft 550 is unidirectional in response to the rotation of the handle 600, with the handle 600 and shaft 550 having the ability to rotate in the opposite direction when the ratchet release 660 is applied. A rotatable handle extension 610 may preferably be gripped by a user or law enforcement official as the handle is rotated, although such handle extension 610 is not a necessity for the effective operation of the device of the invention. The vertical distance between the halves of the outer casing 400 and spool member 500 is somewhat exaggerated in FIG. 2 to illustrate the constituent elements of the device of the present invention. It will be understood, however, that such distance need only be dimensioned to accommodate the cords 200 and 250 in the wound position along the shaft 500, and should also be great enough to allow for easy and effective reeling and unreeling of the cords along such shaft.
A ratchet mechanism is preferred especially during a strenuous takedown when the resisting arrestee is exerting a maximum amount of force to counter the joining of his or her wrists. Each rotation of the handle 600 and revolution of the spool member 500 results in an effective shortening of the cable members 200 and 250 outside the housing assembly 300, which results in the joining of the handcuffs 100 and 150 with a resultant joinder of the arrestee's wrists. The ratchet mechanism allows the user's handle rotation to have a permanent effect, with each joining stroke not to be defeated or reversed by the separating force exerted by the resisting arrestee. Without the ratchet mechanism, the law enforcement official would have to fight to rotate the handle member 600 and would also have to fight to maintain each successive rotation of the spool member 500. While the ratchet mechanism is obviously preferred, the apparatus of the present invention may be operable without such mechanism, although the efficiency of the device would surely be compromised.
FIG. 2A is a top view of an alternative embodiment of the device of the present invention showing two separate inner spools 500a and 500b shown in phantom, one for each cable 200 and 250 respectively, as an alternative to a single spool 500 as shown and described in connection with FIGS. 1-2. Such spools 500a and 500b are preferably gear connected to the ratchet mechanism, so each spool would rotate in a direction opposite the other as the cables are being reeled out or reeled into the housing 300, although other means of interengaging the inner spools with the handle and/or the housing are devisable. One skilled in the art will recognize that a variety of housing assembly embodiments may be used. For example, if a pair of spool members 500a and 500b as shown in FIG. 2A are implemented in the device of the present invention, such spool members could operate either jointly or independently from each other. If a pair of spool members operated or rotated independently of each other, each spool might have an associated release mechanism, so that each spool member could be reeled and unreeled independently of the other, which would allow a law enforcement official to focus on each individual appendage at a time. Furthermore, it might be useful to allow a detainee to extend only a single appendage, such as, for example, to grab a smoke or the like, while the other appendage would remain secured by the official. In addition, in an embodiment of the invention with multiple inner spools as shown, for example, in FIG. 2A, it might be useful to have multiple handles operating such spools, where separate handles might be used to operate individual cables or the like. Consequently, it will be understood that the housing assembly 300 and its constituent spool members 500 may assume a variety of different operable configurations within the scope of the present invention, with each different configuration designed to achieve a particular handcuffing need.
FIG. 3 is a side view and FIG. 4 is top view of an anchoring implement 800 used when a resisting arrestee 950, the lower half of which is shown, for example, in FIGS. 5 and 6, is in the prone position, or lying stomach down. The anchoring implement comprises a gripping section 820, a leveraging section 840 and a connection member 860 designed to cooperate with attachment means 750 shown in FIGS. 1 and 2 for attachment of the housing assembly 300 to the anchoring implement 800. The anchoring implement 800 is preferably held or gripped by the user or law enforcement official along the gripping section 820, which has a preferably rounded edge rectangular profile or cross section to accommodate a user's hand, such profile shown more particularly in FIG. 4. While the arrestee 950 is in the prone position, the leveraging section 840 is slid along arrow 960 between the arrestee's legs 955 with the upper surface 845 of the leveraging section 840 contacting the arrestee's crotch (not specifically shown) until the gripping section 820, and more particularly the inner surface 825, also comes in contact with the resisting arrestee's crotch.
The connection member 860 is shown in FIG. 4 as a ring onto which the attachment means 750, shown in FIGS. 1 and 2, would be clipped. The connection member 860 could take the form of another connection device, as long as it cooperates the form of the attachment means 750. In this case, the attachment means 750 would take the form of a spring clip, screw clip or other latching device. Of course, other means for securing the housing assembly 300 to the anchoring implement 800 may be used.
FIG. 6 is a side, diagrammatic view of an alternative anchoring implement in the form of a thigh strap 900 worn on a user's thigh 999. Instead of using the anchoring implement 800 of FIGS. 3 and 4, where such implement 800 would be placed securely underneath the resisting arrestee's crotch and held in the official's hands, to properly position the restraining device of the present invention, the anchoring implement 900 of FIG. 6 could be used when the law enforcement official places his or her knee 998 against the resisting arrestee's crotch in preparation for the application of the restraining device of the present invention. Of course, the arresting official could implement both anchoring devices 800 and 900 at the same time, i.e. by wearing the thigh strap 900 and holding the implement 800, and depending on the particular circumstances surrounding the takedown of the resisting arrestee, relocate the housing device 300 between such implements 800 and/or 900 using attachment means 750 and connecting means 860. Or, alternative locations on the official's body could be used for placement of alternative anchoring implements, such as along the waist, on the arm or the like. The connecting means 860 on either implement 800 or 900 should be identical for efficient and interchangeable cooperation with attachment means 750 on the housing assembly 300.
Operation of the device of the present invention is relatively straightforward. FIGS. 7 and 8 are overall, or top, views of an arrestee 950 in the stomach-down position, with arms 952 and 954 separated in FIG. 7 and brought together in FIG. 8. The handcuffs 100 and 150 are initially extended so that cables 200 and 250 are at their fully outstretched position. Using the preferred dimensions described above, handcuffs 100 and 150 would now be capable of separately attaching to a resisting arrestee's wrists that are approximately four feet apart from each other. The law enforcement official (not shown) places one handcuff 100 on one of the arrestee's wrists 956, and then places the other handcuff 150 on the other wrist 958. The official (not shown) then rotates the ratcheting handle 600 in the direction of, for example, of diagrammatic arrow 970, which rotates the spool member 500 and reels in the cables 200 and 250, thereby drawing the handcuffs 100 and 150 and the arrestee's wrists together (see FIG. 8). Of course, if the resisting arrestee is in the prone position, the law enforcement official could use the anchoring implements 800 and 900 shown and described in connection with FIGS. 4 through 6.
After the arrestee's wrists have been joined through successive rotations of the handle 600 (see FIG. 8), the law enforcement official may then maintain the handcuffs 100 and 150 on the arrestee's wrists until a safe location is attained, or take the opportunity to apply conventional handcuffs to the arrestee's already joined wrists and thereafter remove the handcuffs 100 and 150 of the device of the present invention. Of course, once the handcuffs 100 and 150 of the invention are removed from the arrestee's wrists, the law enforcement official merely has to apply the ratchet release 660 to fully extend the cables 200 and 250 and handcuffs 100 and 150 in preparation for another capture.
The apparatus of the present invention may be operated by a single law enforcement official, whereby the anchoring implements would serve as storage devices during the initial capture and takedown of the resisting arrestee. A more efficient operation would occur with two law enforcement officials, where one of the officials could concentrate on stabilizing the arrestee's body while the official armed with the device of the present invention could concentrate on applying the handcuffs to the arrestee's wrists and thereafter reeling them together using the ratchet mechanism described herein. With two or more law enforcement officials, the operation of the device of the invention becomes easier, especially during the handcuffing and rotation of the handle member.
The principal operation of the ratchet mechanism is that in order to efficiently rotate the handle 600 on the housing 400, the housing 400 should be stabilized in some fashion. This can be accomplished in several manners, for example, by the arresting officer holding the housing 400 with one hand while operating the handle 600 with the other. This is practical if there are two arresting officers as the other can then aid in guiding the arrestee's arms into position. In such case, it may be desirable to provide a gripping handle or the like on the housing. However, if there is only one arresting officer, the detainee could then flail about his or her arms while being ratcheted in, with possible injury to himself or herself or the arresting officer. In such case, it is necessary that the housing 400 be at least partially stabilized by being secured to some other object such as the anchors shown in FIGS. 3 through 6, or to the body or preferably an appendage of the arresting officer. The connection is provided by the connecting means 860 and attachment means 750 on the housing, which two means are designed to snap, clip or otherwise secure together, holding the housing tethered to the gripping sections 820 or strap 900. This allows the arresting officer to have one hand free after the restraining devices are applied to aid in controlling the arrestee or in warding off blows or the like.
While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention. | A pair of restraints, preferably in the form of handcuffs, are separately connected to a housing assembly by way of elongated cables. The cables are attached at their other ends to a rotatable spool sturdily housed within a box ratchet assembly. Each restraint is first separately applied to a resisting arrestee's wrists. The cables are then reeled into the spool member with a ratcheting motion, enabling a law enforcement official to maintain a controlled joinder of the handcuffs and the arrestee's wrists. | 4 |
REFERENCE TO RELATED DOCUMENTS
The present application is a continuation of U.S. patent application Ser. No. 12/171,911, filed Jul. 11, 2008, which is a continuation of U.S. patent application Ser. No. 11/185,091 filed on Jul. 20, 2005, now U.S. Pat. No. 7,415,464, which is a continuation of U.S. patent application Ser. No. 10/083,812 filed on Feb. 27, 2002 now U.S. Pat. No. 6,931,400, which application claims benefit of priority under 35 U.S.C. §119(e) to U.S. provisional application Ser. No. 60/313,473, filed Aug. 21, 2001, the contents of which are incorporated herein in their entirety.
TECHNICAL FIELD
The present invention relates generally to data management and, more particularly, to methods, systems, and machine-readable media for identifying representative trends in large sets of data.
BACKGROUND OF THE INVENTION
Time series databases, containing data captured over time, are commonly used in such areas as finance, meteorology, telecommunications, and manufacturing to keep track of data valuable to that particular area. For example, financial databases may track stock prices over time. Meteorological parameters such as the temperature over time are stored in scientific databases. Telecommunications and network databases include data derived from the usage of various networking resources over time such as the total number and duration of calls, number of bytes or electronic mails sent out from one ISP to another, amount of web traffic at a site, etc.; manufacturing databases include time series data such as the sale of a specific commodity over time.
Time series data depict trends in the captured data, which users may wish to analyze and understand. Users may wish to know, for a given time window, a trend of “typical” values or an “outlier” trend. Conversely, users may wish to find the time window in which most trends are as similar as possible or clustered. These similar trends are called “representative trends.” Representative trends may be used in lieu of the entire database for quick approximate reasoning. In addition, they can be used for prediction and for identifying and detecting anomalous behavior or intrusion.
By their very nature, time series databases tend to contain large amounts of data. As such, using representative trends of the data reduces the amount of data to be analyzed. However, the large amounts of data must first be processed in order to identify the representative trends.
There is a need in the art to identify representative trends efficiently and quickly in large amounts of data.
SUMMARY OF THE INVENTION
The present invention provides a method, system, and machine-readable medium for identifying representative trends in large amounts of data using sketches. A “sketch” is a lower dimensional vector used to represent higher dimensional data. The present invention includes reducing subvectors of the data to sketches, summing the distances between each sketch and every other sketch, and selecting the data subvector corresponding to the sketch with the lowest summed distance as the representative trend of the data.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart of an embodiment of a method according to the present invention;
FIG. 2 is a flowchart of an exemplary method for generating sketches;
FIGS. 3 and 4 illustrate the method of FIG. 2 ;
FIG. 5 is a flowchart of an exemplary method for comparing sketches;
FIG. 6 is a flowchart of an exemplary method for identifying representative trends in data;
FIGS. 7( a )-( d ) illustrate representative relaxed periods and average trends; and
FIG. 8 is a block diagram of an embodiment of a computer system that can implement the present invention.
DETAILED DESCRIPTION
Embodiments of the present invention provide a method for identifying representative trends in data using sketches. A sketch is a lower dimensional vector used to represent higher dimensional data in higher dimensional vectors. When there are large amounts of data i a higher dimensional vector, the data may first be partitioned into data subvectors of a given dimension. These data subvectors can then be transformed into sketches, which have lower dimensions. The lower dimensions correspond to less data being processed. As such, using sketches of the data, rather than the data itself, provides more efficient, faster performance. So the user may be able to quickly analyze the data without utilizing large amounts of processor time and system memory.
In addition to dimensionality reduction, sketches exhibit distance and synthesis properties that may be used in data analysis. The synthesis property provides a sketch synthesized from existing sketches. This property is particularly useful when existing sketches represent subvectors with a given dimension, but sketches are needed for subvectors with a higher dimension. In such a case, the sketch may be easily synthesized from the existing sketches, rather than calculated from scratch. This synthesis property allows the user to generate sketches once and then use those sketches to represent multiple subvector dimensions without having to reprocess the data in its entirety, thereby saving processor time and system memory.
According to the distance property, the distance between two sketches is comparable to the distance between the subvectors that the sketches represent. Thus, by calculating the distance between two sketches, the distance between the subvectors that the sketches represent may be found with measurable accuracy. In addition, by increasing the sketch dimension, the probability of identifying the data's representative trend may be increased and the error between the data and the sketches reduced. This property allows the user to calculate distances with less data—i.e. the sketches rather than the data itself—thereby saving processor time and system memory. The distance property holds for synthesized sketches as well.
FIG. 1 is a flowchart of an embodiment of a method for identifying representative trends according to the present invention. First, sketches may be generated for data partitioned into subvectors (step 100 ). The data may be partitioned in a number of ways to generate the data subvectors of a given dimension T. Each adjacent subvector may include anywhere from 0 to T−1 overlapping data elements. The final subvectors may have dimensions less than T and may generally be ignored in data analysis. The amount of overlap may affect how well synthesized sketches match their data subvectors and how quickly representative trends are identified. The sketch dimensions may be lower than the subvector dimensions. Each of the generated sketches may then be compared to every other generated sketch for a given subvector dimension T to determine how closely the sketches match each other (step 105 ). The sketch that has the most matches may be considered to be representative of the data. The representative trend may then be identified as the subvector corresponding to the most closely matching sketch and the period of the data may be identified as the subvector dimension T (step 110 ). As a result, the representative trend of the data may be found by processing less data—i.e., the sketches rather than the entire data—thereby saving processing time and system memory. Optionally, this method may be repeated for multiple subvector dimensions The result may then be output to a graphical display, storage device, transmitter, or the like.
Additionally, the present invention offers the following advantages: (a) the best trend may be identified, as opposed to a sinusoidal approximation of it; (b) the trends may be identified using various metrics, as opposed to only a distance metric as is the case for Fourier transforms; (c) for noisy data, filtering may be omitted, unlike the Fourier transform; and (d) representative trends may be identified from subvectors, unlike Fourier transforms which treat the entire data.
FIG. 2 is a flowchart of an exemplary method for generating the sketches. First, the sketch dimension is chosen (step 200 ). By choosing the sketch dimension (or dimension associated with a lower dimensional vector), the user may determine how much error to allow in the final result, i.e. between the identified and the actual representative trend of the data. The higher the dimension, the smaller the error. Next, the data subvectors may be generated by partitioning the data (step 203 ). A random vector with the same dimension as the data subvectors may then be generated to have a normalized, Gaussian distribution (steps 205 , 210 ). The elements of the random vector may be samples from a Gaussian distribution with zero mean and unit variance, normalized to have unit length. The sketch for each data subvector may be calculated using the subvector and the random vector (step 215 ).
The sketch or lower dimensional vector may be calculated using a dot product between the subvector and the random vector. A dot product is a well-known mathematical tool for transforming one vector into another. In the present invention, the subvector may be projected onto the random vector to produce the sketch vector. The advantage is that such a projection reduces the dimension of the data to be analyzed, thereby saving processor time and system memory.
For example, suppose {right arrow over (t)} 2 =(2, 1, 3, 1) and it is desired to construct a sketch vector of dimension 2 . Two vectors {right arrow over (v)} 1 =(−0.45, −0.09, 0.10, 0.87) and {right arrow over (v)} 2 =(−0.19, 0.73, −0.61, 0.21) may be chosen as normalized Gaussian distributed vectors. The dot product may be calculated between {right arrow over (t)} 1 and {right arrow over (v)} 1 to produce the first element of the sketch and between {right arrow over (t)} 1 and {right arrow over (v)} 2 to produce the second element of the sketch. Hence, the sketch of {right arrow over (t)} 1 , S(t 1 ) is (0.18, −1.27).
Optionally, the sketch may be calculated using a polynomial convolution between the subvector and the random vector. A polynomial convolution is a well-known mathematical tool. In the present invention, the subvector may be convolved with the random vector to produce the sketch. The advantages of the convolution are that it reduces the dimension of the data to be analyzed and all the elements of the sketch vector may be calculated together, thereby saving processor time and system memory.
FIG. 3 shows an example using polynomial convolution to compute sketches. A vector {right arrow over (t)}=(2, 1, 3, 1) may be partitioned into subvectors of dimension 2 , t 1 =(2, 1), t 2 =(1, 3) and t 3 =(3, 1). The subvectors may then be convolved with normalized vectors {right arrow over (v)} 1 =(−0.97, −0.20) and {right arrow over (v)} 2 =(0.11, 0.99). The first and second elements of each sketch of dimension 2 may be computed at the same time, such that S 1 =(−2.14, 1.21), S 2 =(−1.57, 3.08), and S 3 =(−3.1, 1.32).
Optionally, the sketch may be calculated by synthesizing it from a pool of sketches. Recall the synthesis property that allows a sketch to be synthesized from existing sketches. A pool of sketches is a small subset of the set of all sketches that could be calculated for a given set of subvectors. To generate the sketch pool, first, two sets of normalized random vectors may be generated (steps 205 , 210 of FIG. 2 ). Then, two sets of sketches may be calculated by either a dot product or a polynomial convolution using the data subvectors and each set of the random vectors. The synthesized sketch may then be calculated by adding corresponding sketches from each set. Typically, one sketch may be selected from each set. The selected sketch represents all or portions of the data to be represented by the synthesized sketch. If the dimension of the subvector of interest is a power of the subvector dimension represented in the sketch pool, then a sketch in the pool representing the same subvectors or subvector portions may be used to represent the subvector of interest. If, however, the dimension is not a power of the subvectors represented in the pool, the sketch may be synthesized as described above.
This pool of sketches may be calculated and stored prior to data analysis. As such, the pool of sketches may be used as a look-up table during analysis. Thus, the synthesized sketch may be calculated very quickly from existing sketches. This synthesis allows sketches to represent subvectors of various dimensions without recalculating random vectors and repartitioning subvectors, thereby saving processor time and system memory.
FIG. 4 shows an example using a sketch pool to compute a sketch. In this example, the sketch representing a subvector of dimension 5 may be computed from a pool of sketches representing subvectors of dimension 4 . The subvector of dimension 5 is {right arrow over (t)}=[2 1 3 1 2]. The first set of pool sketches includes S 1 (t 1 )=(0.09, −1.44) for t 1 [2 1 3 1] and S 1 (t 2 )=(0.51, 1.08) for t 2 =[1 3 1 2]. The second set of pool sketches includes S 2 (t 2 )=(0.61, 2.04) for t 2 and S 2 (t 3 )=(0.45,0.27) for t 3 =[3 1 2 3]. The sketch pool represents subvectors having dimensions that are a power of 2. According to the present invention, since the dimension 5 is not a power of 2, the sketch for {right arrow over (t)} is S′(t)=S 1 (t 1 )+S 2 (t 2 )=(0.70, 0.60). Note that the second, third, and fourth elements of t 1 and t 2 overlap. The more overlap between the added subvectors, the more accurate the synthesized sketch—i.e., the more closely the synthesized sketch matches an actual sketch calculated from scratch. As few as one element may overlap and the accuracy may be high enough for data analysis purposes.
FIG. 5 shows an exemplary method for comparing the sketches. First, sketches of subvectors of dimension T may be acquired (step 905 ). Then, the distance between the sketch of each subvector and the sketches of each of the other subvectors may be calculated (step 910 ). Exemplary distance measurements include the L 2 , L 1 , and L ∞ norms, which are well-known in the art. For each sketch, the inter-sketch distance may be calculated as the sum of the calculated distances (step 915 ). As such, a lowest of the summed distances may be found. This lowest distance indicates how closely sketches match each other and data similarities, i.e., representative trends. According to the distance property, this inter-sketch distance may be substituted for the distance between the data subvectors to compare the subvectors and identify their trends. Advantageously, less data may be processed, thereby saving processor time and system memory.
Optionally, the sketch comparison may be repeated for multiple subvector dimensions T. In this case, the sketches may be recalculated or synthesized for the different dimensions and the distances between them calculated. So, the lowest summed distance would be the lowest distance among all the sketches at all the different subvector dimensions. The advantage of employing this option is that the absolute lowest distance may be selected, indicating the best match and representative trend. This option may be used if the lowest distance exceeds a predetermined threshold, indicating that no good representative trend has been identified at the current subvector dimensions. In this instance, the data may be partitioned into subvectors of a higher dimension, T+1 for example, and the sketches generated using the pool of sketches or, optionally, from scratch.
Optionally, for each subvector dimensions T, the distance between the sketch of the first subvector and the sketches of each of the other subvectors may be calculated (step 910 ). For the first sketch at each T, the inter-sketch distance may be calculated as the sum of the calculated distances (step 915 ). This inter-sketch distance indicates how closely the first sketch matches other sketches. The lowest of the summed distances among the different dimensions may be found. This lowest distance indicates which data subvector dimension T best matches the period of the data.
After the inter-sketch distances are calculated, the representative trend may be identified and output as shown in FIG. 6 . The lowest inter-sketch distance may be selected (step 1000 ). From FIG. 5 , the selected distance may be the lowest distance between the first and the other subvectors among the various subvector dimensions T or the lowest distance between any one and all other subvectors among the various subvector dimensions T. The subvector dimension T that corresponds to the lowest distance may be identified as the period of the data (step 1005 ). As such, the subvector corresponding to the lowest distance may be identified as the representative trend of the data (step 1010 ). The representative trend of data may be output to a graphical display, storage device, transmitter, or the like.
The present invention may be applied to data to find relaxed periods and average trends. It is to be understood that the relaxed period and average trend applications are for exemplary purposes only, as the present invention may be used to find a variety of data patterns or trends.
A relaxed period of data t is defined as the period T of data t′ generated by repeating a subvector of dimension T that most closely matches t—that is, the period T of the data t′ that has the lowest distance from t. The relaxed period's representative trend is the subvector of dimension T. For example, the relaxed period's representative trend of 213123213132213 is 2132 and the relaxed period is 4. FIG. 7( a ) shows an exemplary data vector of dimension 15 . Its corresponding trend is shown in FIG. 7( b ). It includes 4 repetitions of the first four values of the vector in FIG. 7( a ). The vector in FIG. 7( b ) “resembles” the original vector to a great extent. Hence the first four values of the vector in FIG. 7( b ) may be thought of as being representative of the entire vector of FIG. 7( a ).
An average trend is the subvector of data whose total distance to all the other subvectors is the smallest. The corresponding period is the subvector dimension T. For example, if t=113123213132113 as in FIG. 7( c ) and T=3, then some subvectors of interest may be 113, 123, 213, 132, and 113, or a consecutive group of three elements. The average trend is 123 which has a lowest total distance of the other subvectors. The average trend is shown in FIG. 7( d ). FIG. 7( d ) presents a vector derived by 5 repetitions of 123 in FIG. 7( c ). The vector in FIG. 7( d ) is quite similar to that in FIG. 7( c ), and hence may be thought of as representative. The representative trend may be output to a graphical display, storage device, transmitter, or the like.
If the distance between the sketches is zero, then the dimension of the subvectors that the sketches represent is the exact period of the data. Other variants of representative trends may be of interest as well.
Applying the method of the present invention to identify a relaxed period proceeds as follows: Data may be partitioned into subvectors of dimension T. A sketch dimension may be chosen. Then, the subvectors may be reduced to the sketches using an exemplary method, such as a dot product, polynomial convolution, or a sketch pool. If the sketch pool is used, the sketch pool would have been generated and stored prior to this process. After the sketches are generated, the distances between the first sketch and the other sketches may be calculated and summed. This may be repeated for several different subvector dimensions. Then, the lowest distance among the different dimensions may be selected. The relaxed period may be identified as the subvector dimension T corresponding to the lowest distance.
Similarly, to identify an average trend, data may be partitioned into subvectors of dimension T. A sketch dimension may be chosen. Then, the subvectors may be reduced to the sketches using an exemplary method, such as a dot product, polynomial convolution, or a sketch pool. If the sketch pool is used, the sketch pool would have been generated and stored prior to this process. After the sketches are generated, each of their distances to the other sketches may be calculated and summed for each sketch. The lowest distance may be selected. If the lowest distance exceeds a predetermined threshold, the process may be repeated for a different subvector dimension. Or the process may be repeated just to find the absolute lowest distance among several different subvector dimensions. After the lowest distance is selected, the average trend may be identified as the subvector corresponding to the lowest distance.
The methods of FIGS. 2 , 5 , and 6 may be used in combination or alternatively according to the present invention.
The present invention may be implemented for any application in which large amounts of data are used. Exemplary applications include stock market tracking and weather tracking. In such applications, a data set may be generated by sampling the measured data. For example, the price of a particular stock may be sampled every day or atmospheric pressure and temperature measurements may be sampled every hour. Conversely, the data set may be acquired from a source already in sampled form. Representative trends of the data set may then be identified. The identified trends may be output to an appropriate device for graphical display, storage, transmission, or further analysis. Exemplary analysis includes comparing the trends to prior trends to establish patterns of behavior or anomalies.
Some aspects of the present invention may be implemented using the following equations:
To synthesize a sketch, suppose there are two sketches S 1 and S 2 representing two data subvectors of dimension X, where X<T. The user wishes to produce a third sketch S′ that represents a data subvector of dimension T. For a particular sketch—say, S'(t[i, . . . , i+T−1])—of subvector t[i, . . . , i+T−1]), the j-th element of the sketch, where 1≦j≦T, may be synthesized as follows:
S ′( t[i, . . . ,i+T− 1])[ j]=S 1 ( t[i, . . . ,i+X− 1])[ j]+S 2 ( t[i+T−X, . . . ,i+T− 1])[ j ]). (1)
The dimension k of a sketch may be chosen such that
k = 9 log L ɛ 2 , ( 2 )
where L is the number of subvectors of dimension T and ε is a user-defined error. By choosing k, the user also sets ε, thereby determining how much error to allow in the final result.
According to the distance property, for any given set L of subvectors of dimension T, for fixed ε<½ and k, then for any pair of subvectors {right arrow over (t)} i ,{right arrow over (t)} j εL
(1−ε)∥ {right arrow over (t)} i −{right arrow over (t)} j ∥ 2 ≦∥{right arrow over (S)} ′( t i )− {right arrow over (S)} ′( t j )∥ 2 ≦2(1+ε)∥ {right arrow over (t)} i −{right arrow over (t)} j ∥ 2 . (3)
Here ∥{right arrow over (t)} i −{right arrow over (t)} j ∥ 2 is the L 2 distance between the two subvectors.
The distance property holds for synthesized sketches as well. In this case,
(1−ε)∥ {right arrow over (t)} i −{right arrow over (t)} j ∥ 2 ≦∥{right arrow over (S)}′ ( t i )− {right arrow over (S)} ′( t j )∥ 2 ≦2(1+ε)∥ {right arrow over (t)} i −{right arrow over (t)} j ∥ 2 . (4)
So, to compare sketches, the distance between sketches of the subvectors {right arrow over (S)}(t i ), {right arrow over (S)}(t j ) may be calculated as D({right arrow over (S)}(t i ),{right arrow over (S)}(t j )), e.g., using the L 2 distance. The inter-sketch distance may be calculated as the sum of the distances,
C i ( S ( t ( T )))=Σ j D ( {right arrow over (S)} ( t i ), {right arrow over (S)} ( t j )). (5)
The mechanisms and methods of the present invention may be implemented using a general-purpose microprocessor programmed according to the teachings of the present invention. The present invention thus also includes a machine-readable medium which includes instructions which may be executed by a processor to perform a method according to the present invention. This medium may include, but is not limited to, any type of disk including floppy disk, optical disk, CD-ROMs, or any type of media suitable for storing electronic instructions.
FIG. 8 is a block diagram of one embodiment of a computer system that can implement the present invention. The system 2300 may include, but is not limited to, a bus 2310 in communication with a processor 2320 , a system memory module 2330 , and a storage device 2340 according to embodiments of the present invention.
It is to be understood that the structure of the software used to implement the invention may take any desired form, such as a single or multiple programs.
Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A system, method and computer-readable medium are disclosed for identifying representative data using sketches. The method embodiment comprises generating a plurality of vectors from a data set, modifying each of the vectors of the plurality of vectors and selecting one of the plurality of generated vectors according to a comparison of a summed distance between a modified vector associated with the selected generated vector and remaining modified vectors. Modifying the generated vectors may involve reduced each generated vector to a lower dimensional vector. The summed distance then represents a summed distance between the lower dimensional vector and remaining lower dimensional vectors. | 8 |
[0001] This invention was made with government support under Grant 1R43HG003559 awarded by the National Institutes of Health. The government has certain rights in the invention.
TECHNICAL FIELD
[0002] The present disclosure relates to methods for detecting regulatory elements in a cell sample. More specifically, the disclosure relates to methods for detecting regulatory elements in multiple cell samples at the same time and uses arising there from. The present disclosure also provides a vector for detection and analysis of regulatory elements.
BACKGROUND
[0003] The genes of all living organisms are encoded by the nucleic acids DNA and RNA. Each gene encodes a protein that may be produced by the organism through expression of the gene.
[0004] The systems that regulate gene expression respond to a wide variety of developmental and environmental stimuli, thus allowing each cell type to express a unique and characteristic subset of its genes, and to adjust the dosage of particular gene products as needed. The importance of dosage control is underscored by the fact that targeted disruption of key regulatory molecules in mice often results in drastic phenotypic abnormalities (Johnson, R. S., et al., Cell, 71:577-586 (1992)), just as inherited or acquired defects in the function of genetic regulatory mechanisms contribute broadly to human disease.
[0005] Standard molecular biology techniques have been used to analyze the expression of genes in a cell by measuring nucleic acids. These techniques include PCR, northern blot analysis, or other types of DNA probe analysis such as in situ hybridization. Each of these methods allows one to analyze the transcription of only known genes and/or small numbers of genes at a time (Nucl. Acids Res. 19, 7097-7104 (1991); Nucl. Acids Res. 18, 4833-4842 (1990); Nucl. Acids Res. 18, 2789-2792 (1989); European J. Neuroscience 2, 1063-1073 (1990); Analytical Biochem. 187, 364-373 (1990); Genet. Annal Techn. Appl. 7, 64-70 (1990); GATA 8(4), 129-133 (1991); Pro. Natl. Acad. Sci. USA 85, 1696-1700 (1988); Nucl. Acids Res. 19, 1954 (1991); Proc. Natl. Acad. Sci. USA 88, 1943-1947 (1991); Nucl. Acids Res. 19, 6123-6127 (1991); Proc. Natl. Acad. Sci. USA 85, 5738-5742 (1988); Nucl. Acids Res. 16, 10937 (1988)).
[0006] Measurement of the levels of mRNA has also been used to monitor gene expression. Since proteins are transcribed from mRNA, it is possible to detect transcription by measuring the amount of mRNA present. One common method, called “hybridization subtraction”, allows one to look for changes in gene expression by detecting changes in mRNA expression (Nucl. Acids Res. 19, 7097-7104 (1991); Nucl. Acids Res. 18, 4833-4842 (1990); Nucl. Acids Res. 18, 2789-2792 (1989); European J. Neuroscience 2, 1063-1073 (1990); Analytical Biochem. 187, 364-373 (1990); Genet. Annal Techn. Appl. 7, 64-70 (1990); GATA 8(4), 129-133 (1991); Proc. Natl. Acad. Sci. USA 85, 1696-1700 (1988); Nucl. Acids Res. 19, 1954 (1991); Proc. Natl. Acad. Sci. USA 88, 1943-1947 (1991); Nucl. Acids Res. 19, 6123-6127 (1991); Proc. Natl. Acad. Sci. USA 85, 5738-5742 (1988); Nucl. Acids Res. 16, 10937 (1988)).
[0007] Gene expression has also been monitored by measuring levels of the gene product, (i.e., the expressed protein), in a cell, tissue, organ system, or even organism. Measurement of gene expression by measuring the protein gene product may be performed using antibodies known to bind to the particular protein to be detected. A difficulty arises in needing to generate antibodies to each protein to be detected. Measurement of gene expression via protein detection may also be performed using 2-dimensional gel electrophoresis, wherein proteins can be, in principle, identified and quantified as individual bands, and ultimately reduced to a discrete signal. In order to positively analyze each band, each band must be excised from the membrane and subjected to protein sequence analysis (e.g., Edman degradation). However, it tends to be difficult to isolate a sufficient amount of protein to obtain a reliable protein sequence. In addition, many of the bands often contain more multiple proteins.
[0008] Another difficulty associated with quantifying gene expression by measuring an amount of protein gene product in a cell is that protein expression is an indirect measure of gene expression. It is impossible to know from a protein present in a cell when the expression of that protein occurred. Thus, it is difficult to determine whether the protein expression changes over time due to cells being exposed to different stimuli.
[0009] The measurement of the amount of particular activated transcription factors has been used to monitor gene expression. Transcription in a cell is controlled by activated transcription factors which bind to DNA at sites outside the core promoter for the gene and activate transcription. Since activated transcription factors activate transcription, detection of their presence is useful for measuring gene expression. Transcriptional activators are found in prokaryotes, viruses, and eukaryotes.
[0010] In molecular biology, a reporter gene (often simply reporter) is a gene that researchers often attach to another gene of interest in cell culture, animals or plants. Certain genes are chosen as reporters because the characteristics they confer on organisms expressing them are easily identified and measured, or because they are selectable markers. Reporter genes are generally used to determine whether the gene of interest has been taken up by or expressed in the cell or organism population.
[0011] To introduce a reporter gene into an organism, researchers place the reporter gene and the gene of interest in the same DNA construct to be inserted into the cell or organism. For bacteria or eukaryotic cells in culture, this is usually in the form of a circular DNA molecule called a plasmid. It is important to use a reporter gene that is not natively expressed in the cell or organism under study, since the expression of the reporter is being used as a marker for successful uptake of the gene of interest.
[0012] Commonly used reporter genes that induce visually identifiable characteristics usually involve fluorescent proteins; for example, green fluorescent protein (GFP) and the luciferase assay. Other reporters include, for example, beta-galactosidase, X-gal, and chloramphenicol acetyltransferase (CAT).
[0013] Many methods of transfection and transformation—two ways of expressing a foreign or modified gene in an organism—are effective in only a small percentage of a population subjected to the techniques. Thus, a method for identifying those few successful gene uptake events is necessary. Reporter genes used in this way are normally expressed under their own promoter independent from that of the introduced gene of interest; the reporter gene can be expressed constitutively (“always on”) or inducibly with an external intervention such as the introduction of IPTG in the beta-galactosidase system. As a result, the reporter gene's expression is independent of the gene of interest's expression, which is an advantage when the gene of interest is only expressed under certain specific conditions or in tissues that are difficult to access.
[0014] In the case of selectable-marker reporters such as CAT, the transfected population of bacteria can be grown on a substrate that contains chloramphenicol. Only those cells that have successfully taken up the construct containing the CAT gene will survive and multiply under these conditions.
[0015] Reporter genes can also be used to assay for the expression of the gene of interest, which may produce a protein that has little obvious or immediate effect on the cell culture or organism. In these cases the reporter is directly attached to the gene of interest to create a gene fusion. The two genes are under the same promoter and are transcribed into a single polypeptide chain. In these cases it is important that both proteins be able to properly fold into their active conformations and interact with their substrates despite being fused. In building the DNA construct, a segment of DNA coding for a flexible polypeptide linker region is usually included so that the reporter and the gene of interest will only minimally interfere with one another.
[0016] Reporter genes can be used to assay for the activity of a particular promoter in a cell or organism. In this case there is no separate “gene of interest”; the reporter gene is simply placed under the control of the target promoter and the reporter gene product's activity is quantitatively measured. The results are normally reported relative to the activity under a “consensus” promoter known to induce strong gene expression.
[0017] In the past few years, the sequencing of numerous genomes, both eukaryotic and prokaryotic, has generated an enormous amount of data. Although detection of coding regions is common, the major challenge is to annotate the functional non-coding sequences, in particular those involved in gene transcription. Because transcription plays a pivotal role in regulating important processes such as morphogenesis, cell differentiation, tissue specificity, hormonal communication, and cellular stress responses, a need for the identification and functional characterization of transcriptional promoters exists. The methods for detection and analysis of transcriptional promoters can be divided into two categories: computational methods and experimental methods.
[0018] Computational methods for promoter studies incorporate the many public and private databases containing information gathered from studies published by hundreds of laboratories and conducted using conventional labor-intensive and time-consuming approaches. The Eukaryotic Promoter Database (EPD) and the Transcription Regulatory Regions Database (TRRD) contain 1,871 and 703 entries of human promoters, respectively. Other promoter databases, such as TransFac and DBTSS, contain almost 9,000 promoter sequences. However, most of these are derived from in silico primer extension assays (e.g., TransFac), or contain only data about the putative transcriptional start site (e.g., DBTSS). The small numbers of experimentally validated human promoters compared to the 35,000 expected human genes indicate the magnitude of the work still to be done.
[0019] Numerous computer-based promoter prediction methods have been developed (Scherf et al., J. Mol. Biol. 297(3):599-606, 2000; Werner, T. Brief Bioinform. 1(4):372-80, 2000; Loots et al., Gen. Res. 12:832-839, 2002). These methods are limited by the lack of a reliable, standard protocol to predict and identify promoter regions. Promoters are generally only a few base pairs (bp) long, and are embedded within the massive genome. Thus, promoters are much more difficult to find and are easier to confuse than long, patterned coding sequences. Typical computer algorithms for promoter prediction are based on comparisons of unknown sequences with known elements, a strategy which does not allow for identification of new types of promoter elements. Thus, computer-based searches for promoter elements are incomplete and always require experimental confirmation.
[0020] Computational methods based on microarray data have been used to investigate genome-wide transcriptional regulation (Pilpel et al., Nat. Gen. 29(2):153-9, 2001). These techniques allow for the identification of novel functional motif combinations in the promoters of a given organism, and may provide a global view of transcription networks. However, the data provided from these methods also need confirmation by experimental means.
[0021] The experimental methods for investigation of a promoter region and subsequent characterization usually follow a basic protocol. First, upon identification of a new coding sequence, the transcription start site is defined with standard molecular biology tools such as S1 mapping, primer extension, or 5′RACE. Second, the upstream genomic region (up to 10 kb) is cloned and demonstrated to have promoter activity by performing a reporter assay in a transient transfection system. Third, deletion and point mutation analyses are performed to define the important transcriptional cis-acting elements; information about transcriptional regulation may be obtained by applying different induction or repression agents in transient transfection assays. Finally, the transcription factors involved in promoter regulation are identified by Dnase I footprinting, electrophoresis mobility shift assay (EMSA) in the presence or absence of mutant probes and competitors, and EMSA supershift assay.
[0022] Transient-transfection based experimental methods have several disadvantages. These methods measure reporter protein level instead of mRNA level, which is the direct product of the transcription; protein levels may not always correlate with mRNA levels. There are a limited number of reporter assays available (e.g. chloramphenicol acetyl-transferase, β-galactosidase, luciferase, green fluorescent protein (GFP), β-glucuronidase) and the utilization of the same reporter to compare various promoters implies that these promoters must be tested separately and thus these assays are labor-intensive and time-consuming. Since each of the many steps involved (i.e. transfection, induction, harvest, reporter detection) are performed separately for each promoter investigated, usually in duplicate or triplicate, the handling of more than 20 constructs simultaneously is challenging. For each step performed, the time difference between the first and last sample may be significant; therefore incubation periods, cell and reagent quality, for example, may differ from one sample to the other thus introducing more experimental variation. Large amounts of material and reagents are required. Additionally, in order to compare a series of promoters to each other, a second reporter cassette has to be included as an internal control. In some instances, the detection of this control may be as time-consuming and labor-intensive as for the first reporter, and subject to experimental errors. The expression of this internal control can also compete with the gene expression driven by the promoter of interest, and affect the results of the assay. Some assays, such as luciferase and GFP assays, require expensive instrumentation.
[0023] Kim et al. reported an experimental method for isolation and identification of promoters in the human genome (Kim et al. Genome Research 15:830-839, 2005). However, the use of antibodies to identify regions that may be associated with active transcription and the required binding of both RNAP and TFIID as criteria for promoters may lead to the elimination of some promoters that only show partial binding.
[0024] Khambata-Ford et al. reported an experimental method for identification of promoter regions in the human genome by using a retroviral plasmid library-based functional reporter gene assay (Khambata-Ford et al., Gen. Res. 13:1765-1774, 2003). However, in addition to allowing potentially lethal disruption of the target cell genome by random integration of the retroviral vector, the assay relies on the fluorescent reporter GFP for detection and screens the cells via fluorescence-activated cell sorting (FACS).
[0025] Trinklein et al, reported an experimental method for identification and functional analysis of human transcriptional promoters (Trinklein et al, Gen. Res. 13:308-312, 2003) by using a draft sequence of the human genome and cDNA libraries. However, for further analysis and identification of promoter sequences they used a luciferase-based transfection assay.
[0026] The sequencing of genomes has generated a huge amount of data that needs to be annotated. Computational methods are available to detect putative transcriptional promoter regions, but they are not 100% efficient and must be confirmed by experimentation. Unfortunately, the experimental procedures that are currently available to study promoters are time-consuming, laborious, and not easily adapted to large numbers of promoters. Therefore, new techniques for transcriptional studies are needed.
SUMMARY
[0027] The foregoing disadvantages of the previously described methods are overcome by providing a novel reporter system that incorporates unique, non-coding DNA sequences. The object of the present disclosure is to provide a novel reporter system that is specific, inexpensive, and provides an efficient means of promoter detection.
[0028] The present disclosure provides a method for the detection and analysis of DNA promoter sequences. In a preferred embodiment, the present disclosure provides a method for detecting DNA regulatory sequences comprising: a) inserting a promoter sequence candidate into a vector wherein the vector comprises a TAG sequence and wherein the promoter sequence candidate is inserted in a position to drive transcription of the TAG sequence; b) the vector containing the inserted promoter sequence candidate is inserted into a cloning host cell; c) cloning host cells containing different promoter sequence candidates are grown to the same optical density, pooled and the vectors therein are extracted, purified and inserted into a reporter cell line; d) mRNA is extracted from the reporter cell lines wherein the mRNA is directly labeled or is used as template for cDNA or probe synthesis; and e) the labeled mRNA, cDNA or probe is analyzed with an array wherein the array comprises identical or complementary sequence to the TAG sequence. Preferably, the labeled mRNA, cDNA or probe hybridizes to the array and the label of the mRNA, cDNA or probe has a detectable response.
[0029] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequence candidates wherein DNA promoter sequence candidates are integrated into vectors that comprise a TAG sequence, one or more multiple-cloning sites, one or more DNA recombination sequences, a negative selection marker, nucleotide sequences useful for the detection of mRNA sequences such as a T7 promoter sequence and a MA segment, a translation stop codon, a RNA stabilization fragment such as the one from the alpha-globin gene, and a transcription termination signal, such as a poly A signal, and wherein the DNA promoter sequence candidates are located such that they drive the transcription of the TAG sequences. In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences wherein DNA promoter sequence candidates are integrated into a vector comprising a TAG sequence, one or more multiple-cloning sites, both of attP1 and attP2 sequences, a negative selection marker wherein the negative selection marker is the ccdB gene, a T7 promoter sequence, a MA segment, a translation stop codon, an alpha-globin RNA stabilization fragment, and a poly A-signal, and wherein the DNA promoter sequence candidate drives the transcription of the TAG sequence.
[0030] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences wherein DNA promoter sequence candidates are integrated into a vector wherein the vector comprises a TAG sequence, one or more multiple-cloning sites, both of attP1 and attP2 sequences, a negative selection marker, a T7 promoter sequence, a MA sequence wherein the MA sequence is comprised of approximately 25% A, 25% T, 25% G, and 25% C, a translation stop codon, a RNA stabilization fragment, and a transcription termination signal, and wherein the DNA promoter sequence candidate drives the transcription of the TAG sequence. Preferably, the vector is a plasmid. Preferably, the RNA stabilization fragment is from an alpha-globin gene. Preferably, the transcription termination signal is a poly A signal.
[0031] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences wherein DNA promoter sequence candidates are integrated into a vector wherein the vector comprises a TAG sequence, one or more multiple-cloning sites, one or more DNA recombination sequences, a negative selection marker, a T7 promoter sequence, a MA sequence wherein the MA sequence is comprised of approximately 25% A, 25% T, 25% G, and 25% C, a translation stop codon wherein the translation stop is in three frames, a RNA stabilization fragment, and a transcription termination signal, and wherein the DNA promoter sequence candidate is located such that it drives the transcription of the TAG sequence. Preferably, the vector is a plasmid. Preferably, the RNA stabilization fragment is from an alpha-globin gene. Preferably, the transcription termination signal is a poly A signal. Preferably, the DNA recombination sequences are attP1 and attP2.
[0032] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences comprising: (a) integrating DNA promoter sequence candidates within TAG-vectors, wherein the DNA promoter sequence candidate is located such that it drives the transcription of the TAG sequence, wherein the TAG-vector comprises: multiple cloning sites (MCS) for inserting DNA promoter sequence candidate; DNA recombination sequences, such as attP1 and attP2, between which DNA promoter sequence candidates can be inserted; a negative selection marker to maximize the recovery of clones containing promoter sequence inserts, such as ccdB; a nucleotide sequence useful to enable RNA synthesis , preferably a T7 promoter sequence; a unique reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of approximately 25% A, 25% T, 25% G, and 25% C; a three frame translation stop codon; RNA stabilization fragment, preferably from a hemoglobin or alpha-globin gene; and a transcription termination signal, such as a poly A-signal; (b) the TAG-vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to about the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified vector mixture is transfected into a cell line of interest; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support, or beads. Suitable bead compositions include those used in peptide, nucleic acid and organic moeity synthesis, including but not limited to, plastics, ceramics, glass, polystyrene, methylstyrene, acrylic polymers, paramagnetic materials, thoria sol, carbon graphite, titanium dioxide, latex or cross-linked dextrans such as sepharose, cellulose, nylon, cross-linked micelles and teflon many all be used (see Microsphere Detection Guide, Bangs Laboratories, Fishers Ind.). Preferably, the vector is a plasmid. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0033] In another embodiment of the present disclosure, a method is provided wherein each DNA promoter sequence candidate under investigation (for example, computer-predicted DNA promoter sequence candidates, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific DNA promoter, tissue-specific promoters, artificial promoters, etc.) drives the transcription of a unique mRNA that consists of a short oligonucleotide TAG embedded in the 5′ end of a luciferase coding sequence, wherein equimolar amounts of the various promoters under investigation are pooled and transfected into a cell line, and wherein the mRNA levels are quantified by hybridization to the TAG oligonucleotides in an array format. In another embodiment, the reporters are short oligonucleotides TAGs. In another embodiment the length the TAG sequence is between about 16 base pairs and about 200 base pairs, more preferably between about 20 base pairs and about 175 base pairs, more preferably between about 25 base pairs and about 150 base pairs, more preferably between about 30 base pairs and about 125 base pairs, more preferably between about 45 base pairs and about 100 base pairs, more preferably between about 50 base pairs and about 75 base pairs, more preferably about 65 base pairs, and most preferably 60 bp. In another embodiment, all the TAG sequences are designed to have approximately the same melting temperature; this feature allows for the unbiased quantification of various mRNAs by hybridization under the same temperature and ionic strength conditions. In another embodiment, the method enables the detection and quantification of mRNA levels, instead of reporter protein levels, and is unaffected by potentially interfering translation and posttranslational events as in the conventional reporter assays. In another embodiment of the present disclosure, each of the clones containing a TAG vector, preferably a plasmid, is grown to about the same cell density, and the purified vectors, preferably plasmids, of these clonal cultures, containing every DNA promoter sequence candidate, is mixed, and the resulting mixture transfected into a single population of cells creating a competitive environment for the various promoters to recruit transcription factors. In another embodiment, vectors, preferably plasmids, purified from the clonal cell cultures of about equal cell density and containing about equimolar amounts of all the DNA promoter sequences are mixed and used for transfection of a single population of cells and the need for internal controls is eliminated. There are several ways to obtain equimolar amounts of the vectors that carry the various candidate promoters-TAG combinations that are used to transfect reporter cell lines. In another embodiment, equimolar amounts of the vectors can be obtained by: 1) making the vector library; 2) array the vector library (e.g., 96 well plate); 3) take an equal fraction from each clone and pool them all; 4) grow all clones together assuming same growth rate and yield of the same amount of vector per cell; 5) extract the transformation agent (e.g., a vector, plasmid or virus); and 6) transfect the vector (or plasmid or infect virus) into a reporter cell line. Alternately, equimolar amounts of the vector can be obtained by: 1) making the vector library; 2) array the vector library (e.g., 96 well plate); 3) grow each clone individually (e.g., in a deep-well plate in case of bacteria); 4) take an equal fraction from each clone and pool them all; 5) extract the transformation agent (e.g., vector, plasmid or virus); and 6) transfect the vector (or plasmid or infect virus) into the reporter cell line. Alternately, equimolar amounts of the vector can be obtained by: 1) making the vector library; 2) array the vector library (e.g., 96 well plate); 3) grow each clone individually (e.g., in a deep-well plate in case of bacteria); 4) extract the transformation agent (e.g., vector, plasmid or virus) and quantify it; 5) take an equal fraction from each clone (e.g., vector, plasmid or virus) and pool them all; and 6) transfect vector (or plasmid or infect virus) into the reporter cell line. Alternately, equimolar amounts of the vector can be obtained by: 1) making the vector library; 2) take a fraction from each clone, and pool them all; 3) grow all the clones together and assume same growth rate and yield of the same amount of vector per cell; 4) extract transformation agent (e.g., vector, or plasmid or virus); 5) transfect vector (or plasmid or infect virus) into reporter cell line and determine the TAG of interest (e.g., high level of expression); and 6) find the clone in the vector library that contains TAG of interest (e.g., colony hybridization).
[0034] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences comprising: (a) integrating a DNA promoter sequence candidate into a vector, preferably a plasmid, wherein the plasmid comprises a TAG sequence, one or more multiple-cloning sites, at least one DNA recombination sequence, preferably attP1 or attP2, a negative selection marker, preferably ccdB, a nucleotide sequence useful to enable RNA synthesis, such as a T7 promoter sequence, a MA segment, a translation stop codon, a RNA stabilization fragment, preferably from the hemoglobin or alpha-globin gene, and transcription termination signal, such as a poly A-signal, and wherein the DNA promoter sequence candidate is located such that it drives the transcription of the TAG sequence; (b) the vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified vector mixture is transfected into a cell line of interest wherein the use of internal controls is eliminated and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the vector is a plasmid. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0035] In another embodiment, the disclosure provides a method for the detection and analysis of DNA promoter sequences comprising integrating a DNA promoter sequence candidate into a vector, preferably a plasmid, wherein the vector comprises a TAG sequence, one or more multiple-cloning sites, at least one DNA recombination sequence, preferably attP1 or attP2, a negative selection marker, such as ccdB, a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence, a MA segment, a translation stop codon, an RNA stabilization fragment, preferably a hemoglobin or alpha-globin gene, and transcription termination signal, preferably a poly A-signal, and wherein the DNA promoter sequence candidate is located such that it drives the transcription of the TAG sequence.
[0036] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences comprising: (a) integrating a DNA promoter sequence candidate into a vector wherein the vector comprises a TAG sequence, one or more multiple-cloning sites, at least one DNA recombination sequence, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a MA segment, a translation stop codon, a RNA stabilization fragment, and a transcription termination signal, and wherein the DNA promoter sequence candidate is located such that it drives the transcription of the TAG sequence; (b) the vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified vector mixture is transfected into a cell line of interest; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the vector is a plasmid. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the nucleotide sequence useful to enable RNA synthesis is a T7 promoter sequence. Preferably, the transcription termination signal is a poly A-signal. Preferably, the RNA stabilization fragment is from the hemoglobin or alpha-globin gene. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0037] In another embodiment, the present disclosure provides a method for the detection and analysis of DNA promoter sequences comprising: (a) integrating a DNA promoter sequence candidate into a vector wherein the vector comprises a TAG sequence, one or more multiple-candidate sites, at least one DNA recombination sequence, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a MA segment, a translation stop codon, a RNA stabilization fragment, and a transcription termination signal, and wherein the DNA promoter sequence candidate is located such that it drives the transcription of the TAG sequence; (b) the vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified vector mixture is transfected into a cell line of interest and wherein the use of internal controls is eliminated upon transfecting the cells with vectors purified from the clonal cell populations which are of the same cell density and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the vector is a plasmid. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the nucleotide sequence useful to enable RNA synthesis is a T7 promoter sequence. Preferably, the RNA stabilization fragment is from the hemoglobin or alpha-globin gene. Preferably, the transcription termination signal is a poly A-signal. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0038] In another embodiment of the present disclosure, the disclosure provides a method for detection and analysis of DNA promoter nucleotide sequences in a collection of nucleotide sequences, such as genomic library, comprising: (a) mixing promoter sequence candidates with TAG-vectors, wherein the TAG-vector comprises: multiple cloning sites (MCS) for inserting promoter sequence candidate, at least one DNA recombination sequence, such as attP1 or attP2, a negative selection marker to maximize the recovery of clones containing promoter sequence inserts, such as, for example, a ccdB gene, a T7 promoter sequence to enable RNA synthesis, a unique approximate 60 base pair reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of approximately 25% A, 25% T, 25% G, and 25% C, a three frame translation stop codon, a RNA stabilization fragment, such as, for example, alpha-globin or hemoglobin, and transcription termination signal, preferably a poly A-signal; (b) the TAG-vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified vector mixture is transfected into a cell line of interest; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the TAG-vector is a TAG-plasmid. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0039] In another embodiment of the present disclosure, the disclosure provides a method for the detection and analysis of DNA promoter nucleotide sequences in a collection of nucleotide sequences, such as a genomic library, comprising: (a) mixing promoter sequence candidates with TAG-vectors, wherein the TAG-vector comprises: multiple cloning sites (MCS) for inserting promoter sequence candidate, at least one DNA recombination sequence, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a unique approximate 60 base pair reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of approximately 25% A, 25% T, 25% G, and 25% C, a three frame translation stop codon, a RNA stabilization fragment, and transcription termination signal; (b) the TAG-vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified vectors are transfected into a cell line of interest and no internal controls are utilized and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the vectors are plasmids. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the negative selection marker is ccdB. Preferably, the nucleotide sequence to enable RNA synthesis is a T7 promoter sequence. Preferably, the RNA stabilization fragment is from the alpha-globin gene. Preferably, the transcription termination signal is a poly A-signal. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0040] In another embodiment of the present disclosure, the disclosure provides a method for detection and analysis of DNA promoter nucleotide sequences in a collection of nucleotide sequences, such as a genomic library, comprising: (a) mixing promoter sequence candidates with TAG-vectors, wherein the TAG-vector comprises: multiple cloning sites (MCS) for inserting promoter sequence candidate, at least one DNA recombination sequence, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a unique approximate 60 base pair reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of approximately 25% A, 25% T, 25% G, and 25% C, a three frame translation stop codon, a RNA stabilization fragment, and a transcription termination signal; (b) the TAG-vector with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones, containing about equal amounts of vectors are pooled, and the vectors wherein are purified; (d) the purified vectors are transfected into a cell line of interest and wherein the use of internal controls is not utilized; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the TAG-vectors are TAG-plasmids. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the negative selection marker is ccdB. Preferably, the nucleotide sequence to enable RNA synthesis is a T7 promoter sequence. Preferably, the RNA stabilization fragment is from the alpha-globin gene. Preferably, the transcription termination signal is a poly A-signal. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0041] In another embodiment, the disclosure provides a method for analysis and detection of a plurality of DNA promoter nucleotide sequences in a plurality of samples, comprising: (a) mixing DNA promoter sequence candidates, wherein the DNA promoter sequence candidates are, for example, selected from computer-predicted promoter sequence candidates, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc., with TAG vectors, wherein the TAG-vector comprises: multiple cloning sites for inserting DNA promoter sequence candidate, DNA recombination sequences, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a unique approximate 60 base pair reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of about 25% A, 25% T, 25% G, and 25% C, a three frame translation stop codon, a RNA stabilization fragment, and a transcription termination signal; (b) the TAG-vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) the purified plasmid mixture is transfected into a cell line of interest; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the TAG-vectors are TAG-plasmids. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the negative selection marker is ccdB. Preferably, the nucleotide sequence to enable RNA synthesis is a T7 promoter sequence. Preferably, the RNA stabilization fragment is from the alpha-globin gene. Preferably, the transcription termination signal is a poly A-signal. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0042] In another embodiment, the disclosure provides a method for detection and analysis of a plurality of DNA promoter nucleotide sequences in a plurality of samples, comprising: (a) mixing DNA promoter sequence candidates, wherein the promoter sequence candidates are, for example, selected from computer-predicted promoter sequence candidates, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc., with TAG vectors, wherein the TAG-vector comprises: multiple cloning sites for inserting promoter sequence candidate, DNA recombination sequence, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a unique approximate 60 base pair reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of about 25% A, 25% T, 25% G, and 25% C, a three frame translation stop codon, a RNA stabilization fragment, and a transcription termination signal; (b) the TAG-vectors with the promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones contain about equal amounts of vector and are pooled, and the vectors wherein are purified; (d) about equal amounts of the purified vectors are transfected into a cell line of interest; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the TAG-vectors are TAG-plasmids. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the negative selection marker is ccdB. Preferably, the nucleotide sequence to enable RNA synthesis is a T7 promoter sequence. Preferably, the RNA stabilization fragment is from the alpha-globin gene. Preferably, the transcription termination signal is a poly A-signal. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0043] In another embodiment, the disclosure provides a method for the detection and analysis of a plurality of DNA promoter nucleotide sequences in a plurality of samples, comprising: (a) mixing DNA promoter sequence candidates, wherein the promoter sequence candidates are, for example, selected from computer-predicted promoter sequence candidates, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc., with TAG vectors, wherein the TAG-vector comprises: multiple cloning sites for inserting promoter sequence candidate, DNA recombination sequence, a negative selection marker, a nucleotide sequence useful to enable RNA synthesis, a unique approximate 60 base pair reporter TAG, a specific MA segment useful to synthesize probes from RNA, wherein the MA segment is comprised of about 25% A, 25% T, 25% G, and 25% C, a three frame translation stop codon, a RNA stabilization fragment, and a transcription termination signal; (b) the TAG-vectors with the DNA promoter sequence candidate inserts are cloned into a host, preferably Escherichia coli, and the clones are arrayed into a 96-well plate and grown to the same cell density; (c) the resultant clones are pooled, and the vectors wherein are purified; (d) about equal amounts of the purified vectors are transfected into a cell line of interest and wherein the use of internal controls is eliminated; and (e) the RNA is extracted, labeled, and quantified by hybridization to the DNA TAG sequences arrayed on a membrane or glass support. Preferably, the TAG-vectors are TAG-plasmids. Preferably, the DNA recombination sequence is attP1 or attP2. Preferably, the negative selection marker is ccdB. Preferably, the nucleotide sequence to enable RNA synthesis is a T7 promoter sequence. Preferably, the RNA stabilization fragment is from the alpha-globin gene. Preferably, the transcription termination signal is a poly A-signal. Preferably, the label of the mRNA, cDNA or probe has a detectable response.
[0044] The present disclosure provides a vector. In a preferred embodiment, the present disclosure provides a vector into which a DNA promoter sequence candidate is inserted into comprising a TAG sequence, one or more multiple-cloning sites, at least one DNA recombination sequence, a negative selection marker, a RNA polymerase promoter sequence, a MA segment, a translation stop codon, a RNA stabilization fragment, and a transcription termination signal, and wherein the DNA promoter sequence candidate is located such that it can drive the transcription of the TAG sequence. Preferably, the vector is a plasmid.
[0045] In another embodiment, the present disclosure provides for a plasmid vector comprising: a region for insertion of a putative promoter sequence wherein a MCS is located both 5′ and 3′ to the putative promoter sequence; one or more DNA recombination sequences; a T7 sequence; a TAG sequence; a luciferase gene sequence; a MA sequence; and a translational stop sequence. Preferably, the MA sequence is either MA5 or MA4. Preferably, the MA sequence is located 3′ from the TAG sequence. Preferably, the luciferase gene sequence is partial luciferase gene sequence or the full luciferase gene sequence. Preferably, the translational stop sequence is a translational stop sequence in at least one reading frame, more preferably at least two reading frames, and most preferably in three reading frames. Preferably, the DNA recombination sequences are attP1 and attP2.
[0046] In another embodiment, the present disclosure provides a plasmid vector into which a DNA promoter sequence is inserted into comprising a TAG sequence, one or more multiple-cloning sites, one or both of attP1 and attP2 sequences, a negative selection marker, a RNA polymerase promoter sequence, a MA segment, a translation stop codon, a RNA stabilization fragment, and a transcription termination signal, and wherein the DNA promoter sequence is located such that it drives the transcription of the TAG sequence. Preferably, the vector is a plasmid. Preferably, the TAG sequence is between about 16 base pairs to about 200 base pairs, more preferably the vector of the TAG sequence is about 60 base pairs. Preferably, the TAG sequence is located 3′ to the inserted promoter sequence and 5′ to a transcription termination signal. Preferably, the DNA promoter sequence is an enhancer. Preferably, the translation stop codon is a three frame translation stop codon. Preferably, the RNA stabilization fragment is from an alpha-globin gene. Preferably, the transcription termination signal is a poly-A signal. Preferably, the RNA polymerase promoter sequence is a T7 promoter sequence.
[0047] In another embodiment, the disclosure provides for a vector. The disclosure provides a nucleotide sequence for use in the detection and analysis of a promoter nucleotide sequence comprising: a T7 promoter, a TAG sequence, a MA sequence, and a poly A-signal. In another embodiment of the disclosure, the promoter sequence candidate is selected from promoter sequence candidates provided by a computer-predicted model, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc. In another embodiment, the TAG sequence is a DNA sequence composed of random nucleotides. In another embodiment, the length of the TAG sequence is short, preferably between about 16 base pairs to about 200 base pairs, more preferably between about 20 base pairs to about 150 base pairs, more preferably between about 30 base pairs to about 120 base pairs, more preferably between about 40 base pairs to about 100 base pairs, more preferably between about 50 base pairs to about 75 base pairs, and most preferably about 60 base pairs. Within a plurality of TAG sequences, each TAG sequence will have approximately equivalent amounts of the nucleotides A, T, G, and C such that each TAG sequence has approximately the same melting temperature as the other the TAGs. A same melting temperature will allow for the unbiased quantification of various mRNAs by hybridization under the same temperature and ionic strength conditions. In another embodiment, the specific MA segment is useful to synthesize probes from RNA, and the MA segment is comprised of about 25% A, 25% T, 25% G, and 25% C.
[0048] In another embodiment, the disclosure provides a method where a nucleotide sequence is used for the detection and analysis of a promoter nucleotide sequence comprising: a T7 promoter sequence, a TAG sequence, a MA sequence, and a poly A-signal. A DNA promoter sequence candidate may be selected from promoter sequence candidates provided by a computer-predicted model, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc. In preferred embodiments, the TAG sequence is a DNA sequence comprised of short, random nucleotides preferably between about 16 base pairs to about 200 base pairs, more preferably between about 20 base pairs to about 150 base pairs, more preferably between about 30 base pairs to about 120 base pairs, more preferably between about 40 base pairs to about 100 base pairs, more preferably between about 50 base pairs to about 75 base pairs, and most preferably about 60 base pairs.
[0049] In another embodiment, the present disclosure provides a cloning vector comprising a TAG sequence; a transcription termination signal, preferably a poly A-signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, wherein the nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence, and the MA sequence are on the antisense DNA strand. In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a DNA promoter sequence candidate, a TAG sequence, a transcription termination signal, preferably a polyA signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, wherein the DNA promoter sequence candidate, the TAG sequence, and the transcription termination signal, preferably a poly A-signal, are located on the sense DNA strand.
[0050] In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a TAG sequence; a transcription termination signal, preferably a poly A-signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, wherein the DNA promoter sequence candidate is located 5′ to the TAG sequence and wherein the TAG sequence is located 5′ to the transcription termination signal, preferably a poly A-signal. In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a TAG sequence; a transcription termination signal, preferably a poly A-signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, and the TAG sequence is located 3′ to the DNA promoter sequence candidate and the transcription termination signal, preferably a poly A-signal, is located 3′ to the TAG sequence.
[0051] In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a TAG sequence; a transcription termination signal, preferably a poly A-signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, wherein the DNA promoter sequence is operably linked to the TAG sequence. In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a DNA promoter sequence candidate, a TAG sequence, a transcription termination signal, preferably a poly A-signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, and the TAG sequence is operably linked to the transcription termination signal, preferably a poly A-signal.
[0052] In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a TAG sequence; a transcription termination signal, preferably a poly A-signal; a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence; and a MA sequence, wherein the DNA promoter sequence is located 5′ to the TAG sequence, the TAG sequence is located 5′ to the transcription termination signal, preferably a poly A-signal, transcription termination signal is 3′ to a DNA promoter sequence candidate, and the DNA promoter sequence candidate is operably linked to the TAG sequence and TAG sequence is operably linked to the transcription termination signal.
[0053] In another embodiment of the present disclosure, a cloning vector is provided wherein the cloning vector is comprised of a pair of MCS, a TAG sequence, a transcription termination signal, preferably a poly A-signal, a nucleotide sequence useful to enable RNA synthesis, preferably a T7 promoter sequence, and a MA sequence, and a MCS is located 5′ of the DNA promoter sequence candidate and a MCS is located 3′ of the DNA promoter sequence candidate.
[0054] The present disclosure provides an array-based method for promoter detection and analysis. The method provides for transcriptional products that are tagged as they are synthesized, in such a way that one specific transcript is labeled with only one type of TAG, and one TAG labels only one type of transcript. All promoter sequence candidates are analyzed simultaneously in one reaction vial. The transcriptional output is analyzed on conventional arrays and can be detected with procedures that do not require expensive instrumentation. The method fulfills the need for reduction of labor, costs, and provides for the detection of promoter regions from genomic libraries and other related advantages.
[0055] These and other embodiments of the present disclosure will become apparent upon reference to the detailed description and illustrative examples which are intended to exemplify non-limiting embodiments of the disclosure. All references disclosed herein are hereby incorporated by reference in their entirety as if each was incorporated individually.
Glossary
[0056] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Generally, the nomenclature used herein and the laboratory procedures in cell culture, molecular genetics, and nucleic acid chemistry and hybridization described below are those well known and commonly employed in the art. Standard techniques are used for recombinant nucleic acid methods, polynucleotide synthesis, and microbial culture and transformation (e.g., electroporation, lipofection). Generally, enzymatic reactions and purification steps are performed according to the manufacturer's specifications. The techniques and procedures are generally performed according to conventional methods in the art and various general references (see generally, Sambrook et al. Molecular Cloning: A Laboratory Manual, 2d ed. (1989) Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., which is incorporated herein by reference) which are provided throughout this document. Units, prefixes, and symbols may be denoted in their SI accepted form. Unless otherwise indicated, nucleic acids are written left to right in 5′ to 3′ orientation; amino acid sequences are written left to right in amino to carboxyl orientation, respectively. Numeric ranges are inclusive of the numbers defining the range and include each integer within the defined range. Amino acids may be referred to herein by either their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC-IUB Biochemical nomenclature Commission. Nucleotides, likewise, may be referred to by their commonly accepted single-letter codes. Unless otherwise provided for, software, electrical, and electronics terms as used herein are as defined in The New IEEE Standard Dictionary of Electrical and Electronics Terms (5.sup.th edition, 1993). As employed throughout the disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings and are more fully defined by reference to the specification as a whole:
[0057] The term “amplified” refers to the construction of multiple copies of a nucleic acid sequence or multiple copies complementary to the nucleic acid sequence using at least one of the nucleic acid sequences as a template. Amplification systems include, for example, the polymerase chain reaction (PCR) system, ligase chain reaction (LCR) system, nucleic acid sequence based amplification (NASBA, Canteen, Mississauga, Ontario), Q-Beta Replicase systems, transcription-based amplification system (TAS), and strand displacement amplification (SDA) See, e.g., Diagnostic Molecular Microbiology: Principles and Applications, D. H. Persing et al., Ed., American Society for Microbiology, Washington, D.C. (1993). The product of amplification is termed an amplicon.
[0058] The term “array” refers to an array containing nucleic acid samples. An array may be a “macroarray” or a “microarray.” The term “microarray” refers to an array containing nucleic acid samples, also referred to as microscopic DNA ‘spots,’ bound to solid substrates, such as glass microscope slides, plastic, or silicon wafers. Because the physical area occupied by each sample is usually 50-200 μm in diameter, nucleic acid samples representing multiple samples, including, for example, entire genomes, genomic libraries, synthesized DNA samples from computer predicted models, or in deletion mutants of promoters under investigation etc., may be bound to the solid substrate. The solid substrate may include membranes or beads. Macroarrays may be such as those available commercially (Clontech) or synthesized manually. Beads may be of those used in peptide, nucleic acid and organic moiety synthesis, including but not limited to, plastics, ceramics, glass, polystyrene, methylstyrene, acrylic polymers, paramagnetic materials, thoria sol, carbon graphite, titanium dioxide, latex or cross-linked dextrans such as sepharose, cellulose, nylon, cross-linked micelles and Teflon many all be used (see Microsphere Detection Guide, Bangs Laboratories, Fishers Ind.). Microarrays allow the genes of a given sample to be simultaneously monitored with respect to some experimental condition of interest. Microarrays may be fabricated by the mechanical deposition of nucleic acid samples onto a solid substrate. Alternatively, the nucleic acid samples may be manually deposited. The term “DNA microarray” may apply to several different forms of the technology, each differing in the type of nucleic acid applied and the method of application.
[0059] The term “assay marker” or a “reporter gene” refers to a gene that can be detected, or ‘followed.’ The expression of the reporter gene may be measured at either the RNA level, or at the protein level. The gene product may be detected in experimental assay protocol, such as marker enzymes, antigens, amino acid sequence markers, cellular phenotypic markers, nucleic acid sequence markers, and the like. A “reporter gene” (or “reporter”) is a gene that researchers may attach to another gene of interest in cell culture, bacteria, animals, or plants. Some reporters are selectable markers, or confer characteristics upon on organisms expressing them allowing the organism to be easily identified and measured. To introduce a reporter gene into an organism, researchers place the reporter gene and the gene of interest in the same DNA construct to be inserted into the cell or organism. For bacteria or eukaryotic cells in culture, this is usually in the form of a plasmid. Commonly used reporter genes may include fluorescent proteins, luciferase, beta-galactosidase, and selectable markers, such as chloramphenicol, and ccdB.
[0060] The term “cDNA” refers to DNA synthesized from a mature mRNA template. cDNA is most often synthesized from mature mRNA using the enzyme reverse transcriptase. The enzyme operates on a single strand of mRNA, generating its complementary DNA based on the pairing of RNA base pairs (A, U, G, C) to their DNA complements (T, A, C, G). There are several methods known for generating cDNA, for example, to obtain eukaryotic cDNA whose introns have been spliced: a) an eukaryotic cell transcribes the DNA (from genes) into RNA (pre-mRNA); b) the same cell processes the pre-mRNA strands by splicing out introns, and adding a poly-A tail and 5′ Methyl-Guanine cap; c) this mixture of mature mRNA strands are extracted from the cell; d) a poly-T oligonucleotide primer is hybridized onto the poly-A tail of the mature mRNA template. (Reverse transcriptase requires this double-stranded segment as a primer to start its operation.); e) reverse transcriptase is added, along with deoxynucleotide triphosphates (A, T, G, C); f) the reverse transcriptase scans the mature mRNA and synthesizes a sequence of DNA that complements the mRNA template. This strand of DNA is complementary DNA. (see also Current Protocols in Molecular Biology, John Wiley & Sons).
[0061] The term “cloning host cell” refers to a host cell that contains a cloning vector.
[0062] The term “cloning vector” refers to a DNA molecule such as a plasmid, cosmid, or bacterial phage, or virus, such as, for example retroviruses, adeno-associated adenoviruses, lentivirus, baculoviruses and adenoviruses, that has the capability of replicating autonomously in a host cell. Cloning vectors typically contain one or a small number of restriction endonuclease recognition sites at which foreign DNA sequences can be inserted in a determinable fashion without loss of essential biological function of the vector, as well as a selectable marker gene that is suitable for use in the identification and selection of cells transformed with the cloning vector. Selectable marker genes may include genes that provide tetracycline resistance. ampicillin resistance, or other observable features, such as with the ccdB gene.
[0063] The term “detectable marker” encompasses both the selectable markers and assay markers. The term “selectable markers” refers to a variety of gene products to which cells transformed with an expression construct can be selected or screened, including drug-resistance markers, antigenic markers useful in fluorescence-activated cell sorting, adherence markers such as receptors for adherence ligands allowing selective adherence, and the like. When the nucleic acid is prepared or altered synthetically, advantage can be taken of known codon preferences of the intended host where the nucleic acid is to be expressed.
[0064] The term “detectable response” refers to any signal or response that may be detected in an assay, which may be performed with or without a detection reagent. Detectable responses include, but are not limited to, radioactive decay and energy (e.g., fluorescent, ultraviolet, infrared, visible) emission, absorption, polarization, fluorescence, phosphorescence, transmission, reflection or resonance transfer. Detectable responses also include chromatographic mobility, turbidity, electrophoretic mobility, mass spectrum, ultraviolet spectrum, infrared spectrum, nuclear magnetic resonance spectrum and x-ray diffraction. Alternatively, a detectable response may be the result of an assay to measure one or more properties of a biologic material, such as melting point, density, conductivity, surface acoustic waves, catalytic activity or elemental composition. A “detection reagent” is any molecule that generates a detectable response indicative of the presence or absence of a substance of interest. Detection reagents include any of a variety of molecules, such as antibodies, nucleic acid sequences and enzymes. To facilitate detection, a detection reagent may comprise a marker.
[0065] The term “DNA recombination sequences” refers to nucleic acid sequence that provides for efficient transfer of DNA fragments across multiple systems and into multiple vectors. Any DNA fragment flanked by a recombination site can be transferred into any vector that has a corresponding site. Orientation and reading frame are maintained with efficiencies (typically 99%), effectively eliminating the need for secondary sequencing or subcloning after the initial entry clone is made. The transfer of DNA fragments makes use of lambda phage-based site-specific recombination instead of restriction endonuclease and ligase to insert a gene of interest into an expression vector. The DNA recombination sequences, for example, attL, attR, attB, and attP, and enzyme mixtures, for example, LR and BP Clonase, may be used to mediate the lambda recombination reactions. Transferring a gene into a destination vector is accomplished in two steps: 1) clone the gene of interest into an entry vector and 2) mix the entry clone containing the gene of interest in vitro with the appropriate expression vector (destination vector) and enzyme mix. Site-specific recombination between the att sites (attR×attL attB×attP) generates an expression clone and a by-product. The expression clone contains the gene of interest recombined into the destination vector backbone. Following transformation and selection in E. coli, the expression clone is ready to be used for expression in the appropriate host. This lambda-based system is also known as the Gateway® cloning system (Invitrogen Inc., Carlsbad, Calif.).
[0066] The term “electroporation” refers to a significant increase in the electrical conductivity and permeability of the cell plasma membrane caused by an externally applied electrical field. It is used as a way of introducing some substance into a cell, such as loading it with a piece of coding DNA, a molecular probe, or a drug. Pores are formed when the voltage across a plasma membrane exceeds its dielectric strength. If the strength of the applied electrical field and/or duration of exposure to it are properly chosen, the pores formed by the electrical pulse reseal after a short period of time, during which extracellular compounds have a chance to enter into the cell. However, excessive exposure of live cells to electrical fields can result in cell death. Electroporation is done with electroporators, instruments which create the electric current and send it through the cell solution, typically bacteria. The solution is pipetted into a glass or plastic cuvette which has two Al electrodes on its sides. For example, for bacterial electroporation, a suspension of around 50 μl is usually used. Prior to electroporation it is mixed with the plasmid to be transformed. The mixture is pipetted into the cuvette, the voltage is set on the electroporator (2,400 volts is often used) and the cuvette is inserted into the electroporator and an electric current is applied. Immediately after electroporation 1 ml of liquid medium is added to the bacteria (in the cuvette or in a microcentrifuge tube), and the tube is incubated at the bacteria's optimal temperature for an hour or more and then it is spread on an agar plate (see Ausubel, Current Protocols in Molecular Biology, Wiley).
[0067] The term “equimolar” refers to having an equal concentration of moles in one liter of solution.
[0068] The term “expression system” refers to a genetic sequence which includes a protein encoding region which is operably linked to all of the genetic signals necessary to achieve expression of the protein encoding region. Traditionally, the expression system will include a regulatory element such as a promoter or enhancer, to increase transcription and/or translation of the protein encoding region, or to provide control over expression. The regulatory element may be located upstream or downstream of the protein encoding region, or may be located at an intron (non coding portion) interrupting the protein encoding region. Alternatively it is also possible for the sequence of the protein encoding region itself to comprise regulatory ability.
[0069] The term “expression vector” refers a DNA molecule comprising a gene that is expressed in a host cell. Typically, gene expression is placed under the control of certain regulatory elements including promoters, tissue specific regulatory elements, and enhancers. Such a gene is said to be “operably linked to” the regulatory elements.
[0070] The term “functional splice acceptor” refers to any individual functional splice acceptor or functional splice acceptor consensus sequence that permits the construct of the disclosure to be processed such that it is included in any mature, biologically active mRNA, provided that it is integrated in an active chromosomal locus and transcribed as a contiguous part of the pre-messenger RNA of the chromosomal locus.
[0071] The term “homing endonucleases” refers to double stranded DNases that have large, asymmetric recognition sites (12-40 base pairs) and coding sequences that are usually embedded in either introns or inteins. Introns are spliced out of precursor RNAs, while inteins are spliced out of precursor proteins. Homing endonucleases are named using conventions similar to those of restriction endonucleases with intron-encoded endonucleases containing the prefix, “I-” and intein endonucleases containing the prefix, “PI-”. Homing endonuclease recognition sites are extremely rare. For example, an 18 base pair recognition sequence will occur only once in every 7×10 10 base pairs of random sequence. This is equivalent to only one site in 20 mammalian-sized genomes. However, unlike standard restriction endonucleases, homing endonucleases tolerate some sequence degeneracy within their recognition sequence. As a result, their observed sequence specificity is typically in the range of 10-12 base pairs. Homing endonucleases do not have stringently-defined recognition sequences in the way that restriction enzymes do. That is, single base changes do not abolish cleavage but reduce its efficiency to variable extents. The precise boundary of required bases is generally not known.
[0072] The term “host cell” encompasses any cell which contains a vector and preferably supports the replication and/or expression of the vector. Host cells may be prokaryotic cells such as Escherichia coli, or eukaryotic cells such as yeast, insect, amphibian, or mammalian cells. The term as used herein means any cell which may be in culture or in vivo as part of a unicellular organism, part of a multicellular organism, or a fused or engineered cell culture.
[0073] The term “hybridization” refers to the process of combining complementary, single-stranded nucleic acids into a single molecule. Nucleotides will bind to their complement under normal conditions, so two perfectly complementary strands will bind (or ‘anneal’) to each other readily. However, due to the different molecular geometries of the nucleotides, a single inconsistency between the two strands will make binding between them more energetically unfavorable. Measuring the effects of base incompatibility by quantifying the rate at which two strands anneal can provide information as to the similarity in base sequence between the two strands being annealed.
[0074] The term “internal ribosome entry site” (IRES) refers to an element which permits attachment of a downstream coding region or open reading frame with a cytoplasmic polysomal ribosome for purposes of initiating translation thereof in the absence of any internal promoters. An IRES is included to initiate translation of selectable marker protein coding sequences. Examples of suitable IRESes that can be used include the mammalian IRES of the immunoglobulin heavy-chain-binding protein (BiP). Other suitable IRESes are those from the picomaviruses. For example, such IRESes include those from encephalomyocarditis virus (preferably nucleotide numbers 163-746), poliovirus (preferably nucleotide numbers 28-640) and foot and mouth disease virus (preferably nucleotide numbers 369-804). Thus, the IRES are located in the long 5′ untranslated regions of the picornaviruses which can be removed from their viral setting in length to unrelated genes to produce polycistronic mRNAs.
[0075] The term “isolated” refers to material, such as a nucleic acid or a protein, which is: (1) substantially or essentially free from components that normally accompany or interact with it as found in its naturally occurring environment. The isolated material optionally comprises material not found with the material in its natural environment; or (2) if the material is in its natural environment, the material has been synthetically (non-naturally) altered by deliberate human intervention to a composition and/or placed at a location in the cell (e.g., genome or subcellular organelle) not native to a material found in that environment. The alteration to yield the synthetic material can be performed on the material within or removed from its natural state. For example, a naturally occurring nucleic acid becomes an isolated nucleic acid if it is altered, or if it is transcribed from DNA which has been altered, by means of human intervention performed within the cell from which it originates. See, e.g., Compounds and Methods for Site Directed Mutagenesis in Eukaryotic Cells, Kmiec, U.S. Pat. No. 5,565,350; In Vivo Homologous Sequence Targeting in Eukaryotic Cells; Zarling et al., PCT/US93/03868. Likewise, a naturally occurring nucleic acid (e.g., a promoter) becomes isolated if it is introduced by non-naturally occurring means to a locus of the genome not native to that nucleic acid. Nucleic acids which are “isolated” as defined herein are also referred to as “heterologous” nucleic acids.
[0076] The term “inserted” or “introduced” in the context of inserting a nucleic acid into a cell, refers to “transfection” or “transformation” or “transduction” and includes reference to the incorporation of a nucleic acid into a eukaryotic or prokaryotic cell where the nucleic acid may be incorporated into the genome of the cell (e.g., chromosome, plasmid, plastid or mitochondrial DNA), converted into an autonomous replicon, or transiently expressed (e.g., transfected mRNA).
[0077] The terms “label” or “labeled” refers to incorporation of a detectable marker or molecule, e.g., by incorporation of a radiolabeled nucleoside triphosphates or radioisotopes to a nucleic acid that can be detected or measured. Various methods of labeling nucleic acids are known in the art (see Short Protocols in Molecular Biology, 5 th Ed., John Wiley & Sons, 2002) and may be used. Examples of labels for nucleic acids include, but are not limited to, the following: radioisotopes (e.g., 32 P-labeled NTPs and dNTPs; 35 S-labeled NTPs and dNTPs; 3 H , 14 C; 125 I), fluorophores and fluorescent labels (e.g., FITC; rhodamine; lanthanide phosphors; cyanine (Cy3, Cy5); fluorescein; coumarin, SYBR Green); and digoxygenin-11-dUTP.
[0078] The term “MA segment”, also referred to as a “MA sequence,” refers to a nucleotide sequence located downstream from the TAG and upstream of the transcription termination signal in the TAG plasmids and their derivatives. All mRNAs synthesized from the various promoters studied in a single experiment will contain the same MA sequence, to which a complementary primer can anneal and initiate the synthesis of the first strand cDNA in order to make hybridization probes. The MA sequence is usually 20 to 30 nucleotides in length, but may be longer provided the MA sequence does not contain any secondary structure, such as hairpin loops, which would prevent an efficient cDNA synthesis. The MA sequence is composed of approximately 50% GC, such that the melting temperature ranges from about 70° C. to about 75° C. MA sequences are unique among all published nucleotide databases, so that only the TAG-transcripts will serve as template for cDNA synthesis. MA sequences do not contain any of the restriction sites that are used elsewhere in the TAG plasmids for cloning purposes. It cannot function as (or does not contain) a transcriptional promoter or transcription termination signal.
[0079] The term “mixing” refers to combining, joining, uniting, associating, fusing, or ligating at least two distinct nucleotide sequences such that they become one fragment.
[0080] The term “multiple cloning site,” also referred to as an “MCS” or a “polylinker” refers to a short segment of DNA which contains many (usually 20+) sites recognized by restriction enzymes or other endonucleases such as homing endonucleases.
[0081] The term “nucleic acid” refers to a deoxyribonucleotide or ribonucleotide polymer in either single- or double-stranded form, and unless otherwise limited, encompasses known analogues having the essential nature of natural nucleotides in that they hybridize to single-stranded nucleic acids in a manner similar to naturally occurring nucleotides (e.g., peptide nucleic acids).
[0082] The term “nucleotide” refers to a chemical compound that consists of a heterocyclic base, a sugar, and one or more phosphate groups. In the most common nucleotides the base is a derivative of purine or pyrimidine, and the sugar is the pentose deoxyribose or ribose. Nucleotides are the monomers of nucleic acids, with three or more bonding together in order to form a nucleic acid. Nucleotides are the structural units of RNA, DNA, and several cofactors: CoA, FAD, DMN, NAD, and NADP. The purines include adenine (A), and guanine (G); the pyrimidines include cytosine (C), thymine (T), and uracil (U).
[0083] The terms “oligoclonal”, “polyclonal” applied to cell populations indicates a population of cells where some cells within that population are not genetically identical to the rest of the cells of that population. Conversely, the term “monoclonal” or “monoclonal cell population” indicates that all cells within that population are genetically identical. Differences in the “genetic identity” of a population of cells in the context of this disclosure arise by random retroviral integration into different genomic insertion sites.
[0084] The term “operably linked” refers to a functional linkage between a promoter and a second sequence, wherein the promoter sequence initiates and mediates transcription of the DNA sequence corresponding to the second sequence. Generally, operably linked means that the nucleic acid sequences being linked are contiguous and, where necessary to join two protein coding regions, contiguous and in the same reading frame.
[0085] The term “optical density” refers to the absorbance of an optical element for a given wavelength per unit distance. Typically, bacterial cultures are measured at a wavelength of 600 nm.
[0086] The term “polymerase chain reaction” or “PCR” refers to a procedure described in U.S. Pat. No. 4,683,195, the disclosure of which is incorporated herein by reference.
[0087] The term “polynucleotide” refers to a deoxyribopolynucleotide, ribopolynucleotide, or analogs thereof that have the essential nature of a natural ribonucleotide in that they hybridize, under stringent hybridization conditions, to substantially the same nucleotide sequence as naturally occurring nucleotides and/or allow translation into the same amino acid(s) as the naturally occurring nucleotide(s). A polynucleotide can be full-length or a subsequence of a native or heterologous structural or regulatory gene. Unless otherwise indicated, the term includes reference to the specified sequence as well as the complementary sequence thereof. Thus, DNAs or RNAs with backbones modified for stability or for other reasons are “polynucleotides” as that term is intended herein. Moreover, DNAs or RNAs comprising unusual bases, such as inosine, or modified bases, such as tritylated bases, to name just two examples, are polynucleotides as the term is used herein. It will be appreciated that a great variety of modifications have been made to DNA and RNA that serve many useful purposes known to those of skill in the art. The term polynucleotide as it is employed herein embraces such chemically, enzymatically or metabolically modified forms of polynucleotides, as well as the chemical forms of DNA and RNA characteristic of viruses and cells, including among other things, simple and complex cells.
[0088] The terms “polypeptide”, “peptide” and “protein” are used interchangeably herein to refer to a polymer of amino acid residues. The terms apply to amino acid polymers in which one or more amino acid residue is an artificial chemical analogue of a corresponding naturally occurring amino acid, as well as to naturally occurring amino acid polymers. The essential nature of such analogues of naturally occurring amino acids is that, when incorporated into a protein that protein is specifically reactive to antibodies elicited to the same protein but consisting entirely of naturally occurring amino acids. The terms “polypeptide”, “peptide” and “protein” are also inclusive of modifications including, but not limited to, glycosylation, lipid attachment, sulfation, gamma.-carboxylation of glutamic acid residues, hydroxylation and ADP-ribosylation. It will be appreciated, as is well known and as noted above, that polypeptides are not entirely linear. For instance, polypeptides may be branched as a result of ubiquitination, and they may be circular, with or without branching, generally as a result of posttranslational events, including natural processing event and events brought about by human manipulation which do not occur naturally. Circular, branched and branched circular polypeptides may be synthesized by non-translation natural process and by entirely synthetic methods, as well.
[0089] The term “primer” refers to a nucleic acid which, when hybridized to a strand of DNA, is capable of initiating the synthesis of an extension product in the presence of a suitable polymerization agent. The primer preferably is sufficiently long to hybridize uniquely to a specific region of the DNA strand. A primer may also be used on RNA, for example, to synthesize the first strand of cDNA.
[0090] The term “promoter” refers to a region of DNA upstream, downstream, or distal, from the start of transcription and involved in recognition and binding of RNA polymerase and other proteins to initiate transcription. For example, T7, T3 and Sp6 are RNA polymerase promoter sequences. In RNA synthesis, promoters are a means to demarcate which genes should be used for messenger RNA creation and by extension, control which proteins the cell manufactures. Promoters represent critical elements that can work in concert with other regulatory regions (enhancers, silencers, boundary elements/insulators) to direct the level of transcription of a given gene.
[0091] The term “promoter sequence candidate” refers to a nucleotide sequence that contains a putative promoter sequence. A promoter sequence candidate may be provided by a computer-predicted model, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc.
[0092] The term “promoterless” refers to a protein coding sequence contained in a vector, retrovirus, adenovirus, adeno-associated virus or retroviral provirus that is not directly or significantly under the control of a promoter within the vector, whether it be in RNA or DNA form. The vector, plasmid, viral or otherwise, may contain a promoter, but that promoter cannot be positioned or configured such that it directly or significantly regulates the expression of the promoterless protein coding sequence.
[0093] The term “protein coding sequence” refers a nucleotide sequence encoding a polypeptide gene which can be used to distinguish cells expressing the polypeptide gene from those not expressing the polypeptide gene. Protein coding sequences include those commonly referred to as selectable markers. Examples of protein coding sequences include those coding a cell surface antigen and those encoding enzymes. A representative list of protein coding sequences include thymidine kinase, beta.-galactosidase, tryptophan synthetase, neomycin phosphotransferase, histidinol dehydrogenase, luciferase, chloramphenicol acetyltransferase, dihydrofolate reductase (DHFR); hypoxanthine guanine phosphoribosyl transferase (HGPRT), CD4, CD8 and hygromycin phosphotransferase (HYGRO).
[0094] The term “recombinant” refers to a cell or vector that has been modified by the introduction of a heterologous nucleic acid or the cell that is derived from a cell so modified. Thus, for example, recombinant cells express genes that are not found in identical form within the native (non-recombinant) form of the cell or express native genes that are otherwise abnormally expressed, under-expressed or not expressed at all as a result of deliberate human intervention. The term “recombinant” as used herein does not encompass the alteration of the cell or vector by naturally occurring events (e.g., spontaneous mutation, natural transformation transduction/transposition) such as those occurring without deliberate human intervention.
[0095] The term “recombinant expression cassette” refers to a nucleic acid construct, generated recombinantly or synthetically, with a series of specified nucleic acid elements which permit transcription of a particular nucleic acid in a host cell. The recombinant expression cassette can be incorporated into a plasmid, chromosome, mitochondrial DNA, virus, or nucleic acid fragment. Typically, the recombinant expression cassette portion of an expression vector includes, among other sequences, a nucleic acid to be transcribed, a promoter, and a transcription termination signal such as a poly-A signal.
[0096] The term “recombinant host” refers to any prokaryotic or eukaryotic cell that contains either a cloning vector or an expression vector. This term also includes those prokaryotic or eukaryotic cells that have been genetically engineered to contain the cloned genes, or gene of interest, in the chromosome or genome of the host cell.
[0097] The term “regulatory sequence” (also called regulatory region or regulatory element) refers to a promoter, enhancer or other segment of DNA where regulatory proteins such as transcription factors bind preferentially. They control gene expression and thus protein expression.
[0098] The term “reporter cell line” refers to prokaryotic or eukaryotic cells that contain a reporter or assay marker.
[0099] The term “restriction digestion” refers to a procedure used to prepare DNA for analysis or other processing. Also known as DNA fragmentation, it uses a restriction enzyme to selectively cleave strands of DNA into shorter segments.
[0100] The term “restriction enzyme” (or restriction endonuclease) refers to an enzyme that cuts double-stranded DNA. The enzyme makes two incisions, one through each of the phosphate backbones of the double helix without damaging the bases. Restriction enzymes are classified biochemically into four types, designated Type 1, Type II, Type III, and Type IV. In Type I and Type III systems, both the methylase and restriction activities are carried out by a single large enzyme complex. Although these enzymes recognize specific DNA sequences, the sites of actual cleavage are at variable distances from these recognition sites, and can be hundreds of bases away. Both require ATP for their proper function. In Type II systems, the restriction enzyme is independent of its methylase, and cleavage occurs at very specific sites that are within or close to the recognition sequence. Type II enzymes are further classified according to their recognition site. Most Type II enzymes cut palindromic DNA sequences, while Type IIa enzymes recognize non-palindromic sequences and cleavage outside of the recognition site. Type IIb enzymes cut sequences twice at both sites outside of the recognition sequence. In Type IV systems, the restriction enzymes target only methylated DNA.
[0101] The term “restriction sites” or “restriction recognition sites” refer to particular sequences of nucleotides that are recognized by restriction enzymes as sites to cut the DNA molecule. The sites are generally, but not necessarily, palindromic, (because restriction enzymes usually bind as homodimers) and a particular enzyme may cut between two nucleotides within its recognition site, or somewhere nearby.
[0102] The term “reverse transcription” or “reverse transcription polymerase chain reaction” (RT-PCR) refers to amplifying a defined piece of a ribonucleic acid (RNA) molecule. The RNA strand is first reverse transcribed into its DNA complement or complementary DNA, followed by amplification of the resulting DNA using polymerase chain reaction.
[0103] The term “selectable marker” refers to a gene introduced into a cell, especially a bacterium or to cells in culture that confers a trait suitable for artificial selection. They are a type of reporter gene used in laboratory microbiology, molecular biology, and genetic engineering to indicate the success of a transfection or other procedure meant to introduce foreign DNA into a cell. For example, analysis of gene function frequently requires the formation of cells that contain the studied gene in a stably integrated form. In some situations, few cells may stably integrate DNA thus a dominant selectable marker is used to permit isolation of stable transfectants. Selectable markers may include: antibiotics (ampicillin) and ‘suicide’ genes (for example ccdB). Positive selective markers may utilize: adenosine deaminase (thymidine, hypoxanthine, 9-β-D-xylofuranosyl adenine, 2′-deoxycoformycin), aminoglycoside phosphotransferase (neomycin, G418, gentamycin, kanamycin), Bleomycin (bleomycin, phleomycin, zeocin), cytosine deaminase (N-(phosphonacetyl)-L-aspartate, inosine, cytosine); dehydrofolate reductase (methotrexate, aminopterin); histidinol dehydrogenase (histindol); hygromycin-B-phosphotransferase (hygromycin-B); puromycin-N-acetyl transferase (puromycin); thymidine kinase (hypoxanthine, aminopterin, thymidine, glycine); and xanthine-guanine phosphorriobsyltransferase (xanthine, hypoxanthine, thymidine, aminopterin, mycophenolic acid, L-glutamine). Negative selectable markers may utilize: cytosine deaminase (5-fluorocytosine); diptheria toxin; ccdB, and HSV-TK.
[0104] The term “selectively hybridizes” refers to hybridization, under stringent hybridization conditions, of a nucleic acid sequence to a specified nucleic acid target sequence to a detectably greater degree (e.g., at least 2-fold over background) than its hybridization to non-target nucleic acid sequences and to the substantial exclusion of non-target nucleic acids. Selectively hybridizing sequences typically have about at least 80% sequence identity, preferably 90% sequence identity, and most preferably 100% sequence identity (i.e., complementary) with each other.
[0105] The term “sense” refers to the general concept used to compare the polarity of nucleic acid molecules to other nucleic acid molecules. Generally, a DNA sequence is called “sense” if its sequence is the same as that of a messenger RNA copy that is translated into protein. The sequence on the opposite strand is complementary to the sense sequence and is therefore called the “antisense” sequence.
[0106] The term “TAG” refers to a DNA sequence composed of random nucleotides, in which each position has an equal probability of having any of the four deoxynucleotides (A, C, T, and G). Other bases, such as inosine, uracil, 5-methylcytosine, 8-azaguanine, 2,6-diaminopurine, 5 bromouracil, and other derivatives may be incorporated in their nucleotide form into the sequences. The length of the TAG sequence is short, preferably between about 16 bp to about 200 bp, more preferably between about 20 to about 150 bp, more preferably between about 30 to about 120 bp, more preferably between about 40 to about 100 bp, more preferably between about 50 to about 75 bp, and most preferably about 60 bp. The sequences are preferably different or distinct enough to avoid annealing to each other at times when the oligonucleotide is present as a single strand. In addition, the sequence should not be self-complementary, so as to avoid the formation of primer-dimers during amplification. Within a plurality of TAG sequences, each TAG sequence will have approximately equivalent amounts of the nucleotides A, T, G, and C such that each TAG sequence has approximately the same melting temperature as the other TAGs. A same melting temperature will allow for the unbiased quantification of various mRNAs containing each a different TAG sequence by hybridization under the same temperature and ionic strength conditions. Within a plurality of TAG sequences, the nucleotide sequence of each individual TAG sequence is unique to the individual TAG of the plurality.
[0107] The term “transcription termination signal” refers to a section of genetic sequence that marks the end of gene or operon on genomic DNA for transcription. In prokaryotes, two classes of transcription termination signals are known: 1) intrinsic transcription termination signals where a hairpin structure forms within the nascent transcript that disrupts the mRNA-DNA-RNA polymerase ternary complex; and 2) Rho-dependent transcription termination signal that require Rho factor, an RNA helicase protein complex to disrupt the nascent mRNA-DNA-RNA polymerase ternary complex. In eukaryotes, transcription termination signals are recognized by protein factors that co-transcriptionally cleave the nascent RNA at a polyadenlyation signal (i.e, “poly-A signal” or “poly-A tail”) halting further elongation of the transcript by RNA polymerase. The subsequent addition of the poly-A tail at this site stabilizes the mRNA and allows it to be exported outside the nucleus. Termination sequences are distinct from termination codons that occur in the mRNA and are the stopping signal for translation, which may also be called nonsense codons.
[0108] The term “translational stop sequence” refers to a sequence which codes for the translational stop codons. In some embodiments, the translational stop sequence may be in one, two, or three reading frames.
[0109] The term “transfection” refers to the introduction of foreign DNA into eukaryotic or prokaryotic cells. Transfection typically involves opening transient holes in cells to allow the entry of extracellular molecules, typically supercoiled plasmid DNA, but also siRNA, among others. There are various methods of transfecting cells. One method is by calcium phosphate. HEPES-buffered saline solution containing phosphate ions is combined with a calcium chloride solution containing the DNA to be transfected. When the two are combined, a fine precipitate of calcium phosphate will form, binding the DNA to be transfected on its surface. The suspension of the precipitate is then added to the cells to be transfected. The cells take up precipitate and the DNA. Alternatively, MgCl 2 or RbCl can be used. Other methods of transfection include electroporation, heat shock, proprietary transfection agents, dendrimers, and the use of liposomes. Liposomes are small, membrane-bounded bodies that fuse to the cell membrane releasing DNA into the cell. For eukaryotic cells, lipid-cation based transfection is typically used. Other methods of transfection include use of the gene gun and viruses. For stable transfection another gene is co-transfected, which gives the cell some selection advantage, such as resistance towards a certain toxin. If the toxin, towards which the co-transfected gene offers resistance, is then added to the cell culture, only those cells with the foreign genes inserted into their genome will be able to proliferate, while other cells will die. After applying this selection pressure for some time, only the cells with a stable transfection remain and can be cultivated further. A common agent for stable transfection is Geneticin, also known as G418, which is a toxin that can be neutralized by the product of the neomycin resistant gene (see Bacchetti and Graham. Transfer of the gene for thymidine kinase to thymidine kinase - deficient human cells by purified herpes simplex viral DNA. 1977. Proc. Natl. Acad. Sci. USA 74(4):1590-94). Conventional transient transfection assays may incorporate internal controls, such as pRL-SV40 (Promega, Inc.) and may be used in combination with any experimental reporter vector to co-transfect mammalian cells.
[0110] The term “transformation” refers to the genetic alteration of a cell resulting from the introduction, uptake, and expression of foreign genetic material (DNA or RNA). In bacteria, transformation refers to a genetic change brought about by taking up and expressing DNA, and “competence” refers to a state of being able to take up DNA. Competent cells may be generated by a laboratory procedure in which cells are passively made permeable to DNA, using conditions that do not normally occur in nature, thus cells that have been manipulated to accept foreign DNA are called “competent cells”. These procedures are comparatively easy and simple, and can be used to genetically engineer bacteria. These procedures may include chilling cells in the presence of divalent cations, such as CaCl 2 , which prepares the cell walls to become permeable to plasmid DNA. Cells are incubated with the DNA and then briefly heat shocked (e.g., 42° C. for 30-120 seconds), which causes the DNA to enter the cell. This method works well for circular plasmid DNAs. Electroporation is another way to allow DNA to enter cells and involves briefly shocking cells with an electric field of 100-200 V. Plasmid DNA enters cells via the holes created in the cell membrane by the electric shock; natural membrane-repair mechanisms close these holes afterwards. Yeasts may be transformed, for example, by High Efficiency Transformation (see Gietz, R. D., and R. A. Woods. 2002 Transformation of Yeast by the Liac/SS Carrier DNA/PEG Method. Methods in Enzymology 350:87-96); the Two-hybrid System Protocol (see Gietz, R. D., B. Triggs-Raine, A. Robbins, K. C. Graham, and R. A. Woods. 1997 Identification of proteins that interact with a protein of interest: Applications of the yeast two - hybrid system. Mol Cell Biochem 172:67-79); and the Rapid Transformation Protocol (see Gietz, R. D., and R. A. Woods. 2002 Transformation of Yeast by the Liac/SS Carrier DNA/PEG Method. Methods in Enzymology 350:87-96).
[0111] The term “vector” refers to a nucleic acid used in transfection of a host cell and into which can be inserted a polynucleotide. Vectors are frequently replicons. Expression vectors permit transcription of a nucleic acid inserted therein. Some common vectors include plasmids, cosmids, viruses, phages, recombinant expression cassettes, and transposons. The term “vector” may also refer to an element which aids in the transfer of a gene from one location to another. Vectors may include expression vectors and cloning vectors.
[0112] The following terms are used to describe the sequence relationships between two or more nucleic acids or polynucleotides: (a) “reference sequence”, (b) “comparison window”, (c) “sequence identity”, (d) “percentage of sequence identity”, and (e) “substantial identity”. The term “reference sequence” refers to a sequence used as a basis for sequence comparison. A reference sequence may be a subset or the entirety of a specified sequence; for example, as a segment of a full-length cDNA or gene sequence, or the complete cDNA or gene sequence.
[0113] The term “comparison window” refers to a contiguous and specified segment of a polynucleotide sequence, wherein the polynucleotide sequence may be compared to a reference sequence and wherein the portion of the polynucleotide sequence in the comparison window may comprise additions or deletions (i.e., gaps) compared to the reference sequence (which does not comprise additions or deletions) for optimal alignment of the two sequences. Generally, the comparison window is at least 20 contiguous nucleotides in length, and optionally can be 30, 40, 50, 100, or longer. Those of skill in the art understand that to avoid a high similarity to a reference sequence due to inclusion of gaps in the polynucleotide sequence, a gap penalty is typically introduced and is subtracted from the number of matches.
[0114] All TAGs should lack homology to other TAGs used within the same assay. Dependent upon the method the probe is made, the homology of the TAG with known nucleic acid sequences may be acceptable. For example, if the probe is made by labeling mRNA directly, for example with polyA polymerase (see, for example, Aviv and Leder, Proc Natl Acad Sci USA. June 1972;69(6): 1408-12), the TAG-containing mRNAs, the endogenous mRNAs and possibly the tRNA, and rRNA may be labeled as well. Hybridization by these latter RNAs may interfere with detection by the probe. The TAGs should not have homology with any known sequence that is transcribed into RNA, including mRNA, tRNA, rRNA, etc. If the probe is made by labeling the first-strand cDNA, there are two possibilities: 1) if oligo(dT) is used as a primer, all first strand cDNA synthesized from mRNAs will be labeled, including the TAG-containing mRNAs and the endogenous mRNAs. These latter cDNAs may interfere with detection by the probe, thus the TAGs should not have homology with any known sequence that is transcribed into RNA; and 2) if oligo(dT)+anchor is used as a primer “B” (where the anchor would be a short stretch of nucleotides corresponding to the 3′ end of the mRNA, immediately preceding the polyA) only cDNAs synthesized from mRNAs terminated by the same or similar transcription termination signal as the one used for the TAG constructs will be labeled. Thus if a particular kind of endogenous mRNA is recognized by the oligo(dT)-anchor primer, that specific mRNA would interfere with detection by the probe, therefore the TAG should not share homology with that specific mRNA. If the probe is made by PCR, in addition to the homology considerations discussed above with regard to the synthesis of the first strand cDNA, there are two additional considerations. First, linear amplification of the first strand cDNA is made using a primer (A) corresponding to a region common to all the TAG-mRNAs that is located 5′ to the TAG. This situation may arise when the vector (plasmid or viral DNA), from which the probe may be made from, is removed and the primer B used for the first strand cDNA synthesis is removed as well. Accordingly, if the first strand cDNA was synthesized using oligo(dT) as the primer, then the TAGs may not have homology with any known sequence that is transcribed into mRNA, and that shares sequence identity with primer A, and if the first strand cDNA was synthesized using oligo(dT)-anchor as the primer, then the TAGs may not have homology with any known sequence that is transcribed into mRNA that shares sequence identity with both the 3′ end as the TAG-mRNA and primer A. Second, exponential amplification of the first strand cDNA using primer (A) and the oligo(dT)-based primer occurs. In this situation, the antisense strand may be used as a probe and the printing of the assay membrane with the sense-strand oligonucleotides so that the vector does not have to be removed, as discussed above. Thus, at times, one can use TAGs with sequences that are found elsewhere in databases. A specific TAG should not share sequence homology with any other TAG used simultaneously in the same assay and with any DNA or RNA molecule that will be labeled during the synthesis of the probe, regardless of the method used to synthesize the probe.
[0115] Methods of alignment of sequences for comparison are well-known in the art. Optimal alignment of sequences for comparison may be conducted by the local homology algorithm of Smith and Waterman, Adv. Appl. Math. 2:482 (1981); by the homology alignment algorithm of Needleman and Wunsch, J. Mol. Biol. 48:443 (1970); by the search for similarity method of Pearson and Lipman, Proc. Natl. Acad. Sci. 85:2444 (1988); by computerized implementations of these algorithms, including, but not limited to: CLUSTAL in the PC/Gene program by Intelligenetics, Mountain View, Calif.; GAP, BESTFIT, BLAST, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group (GCG), 575 Science Dr., Madison, Wis., USA; the CLUSTAL program is well described by Higgins and Sharp, Gene 73:237-244 (1988); Higgins and Sharp, CABIOS 5:151-153 (1989); Corpet, et al., Nucleic Acids Research 16:10881-90 (1988); Huang, et al., Computer Applications in the Biosciences 8:155-65 (1992), and Pearson, et al., Methods in Molecular Biology 24:307-331 (1994). The BLAST family of programs which can be used for database similarity searches includes: BLASTN for nucleotide query sequences against nucleotide database sequences; BLASTX for nucleotide query sequences against protein database sequences; BLASTP for protein query sequences against protein database sequences; TBLASTN for protein query sequences against nucleotide database sequences; and TBLASTX for nucleotide query sequences against nucleotide database sequences. See, Current Protocols in Molecular Biology, Chapter 19, Ausubel, et al., Eds., Greene Publishing and Wiley-Interscience, New York (1995).
[0116] Unless otherwise stated, sequence identity/similarity values provided herein refer to the value obtained using the BLAST 2.0 suite of programs using default parameters. Altschul et al., Nucleic Acids Res. 25:3389-3402 (1997). Software for performing BLAST analyses is publicly available, e.g., through the National Center for Biotechnology-Information (http://www.hcbi.nlm.nih.gov/). This algorithm involves first identifying high scoring sequence pairs (HSPs) by identifying short words of length W in the query sequence, which either match or satisfy some positive-valued threshold score T when aligned with a word of the same length in a database sequence. T is referred to as the neighborhood word score threshold (Altschul et al., supra). These initial neighborhood word hits act as seeds for initiating searches to find longer HSPs containing them. The word hits are then extended in both directions along each sequence for as far as the cumulative alignment score can be increased. Cumulative scores are calculated using, for nucleotide sequences, the parameters M (reward score for a pair of matching residues; always>0) and N (penalty score for mismatching residues; always<0). For amino acid sequences, a scoring matrix is used to calculate the cumulative score. Extension of the word hits in each direction are halted when: the cumulative alignment score falls off by the quantity X from its maximum achieved value; the cumulative score goes to zero or below, due to the accumulation of one or more negative-scoring residue alignments; or the end of either sequence is reached. The BLAST algorithm parameters W, T, and X determine the sensitivity and speed of the alignment. The BLASTN program (for nucleotide sequences) uses as defaults a word length (W) of 11, an expectation (E) of 10, a cutoff of 100, M=5, N=−4, and a comparison of both strands. For amino acid sequences, the BLASTP program uses as defaults a word length (W) of 3, an expectation (E) of 10, and the BLOSUM62 scoring matrix (see Henikoff & Henikoff (1989) Proc. Natl. Acad. Sci. USA 89:10915).
[0117] In addition to calculating percent sequence identity, the BLAST algorithm also performs a statistical analysis of the similarity between two sequences (see, e.g., Karlin & Altschul, Proc. Natl. Acad. Sci. USA 90:5873-5787 (1993)). One measure of similarity provided by the BLAST algorithm is the smallest sum probability (P(N)), which provides an indication of the probability by which a match between two nucleotide or amino acid sequences would occur by chance. BLAST searches assume that proteins can be modeled as random sequences. However, many real proteins comprise regions of nonrandom sequences which may be homopolymeric tracts, short-period repeats, or regions enriched in one or more amino acids. Such low-complexity regions may be aligned between unrelated proteins even though other regions of the protein are entirely dissimilar. A number of low-complexity filter programs can be employed to reduce such low-complexity alignments. For example, the SEG (Wooten and Federhen, Comput. Chem., 17:149-163 (1993)) and XNU (Claverie and States, Comput. Chem., 17:191-201 (1993)) low-complexity filters can be employed alone or in combination. As used herein, “sequence identity” or “identity” in the context of two nucleic acid or polypeptide sequences refers to the residues in the two sequences which are the same when aligned for maximum correspondence over a specified comparison window. When percentage of sequence identity is used in reference to proteins it is recognized that residue positions which are not identical often differ by conservative amino acid substitutions, where amino acid residues are substituted for other amino acid residues with similar chemical properties (e.g. charge or hydrophobicity) and therefore do not change the functional properties of the molecule. Where sequences differ in conservative substitutions, the percent sequence identity may be adjusted upwards to correct for the conservative nature of the substitution. Sequences which differ by such conservative substitutions are said to have “sequence similarity” or “similarity”. Means for making this adjustment are well-known to those of skill in the art. Typically this involves scoring a conservative substitution as a partial rather than a full mismatch, thereby increasing the percentage sequence identity. Thus, for example, where an identical amino acid is given a score of 1 and a non-conservative substitution is given a score of zero, a conservative substitution is given a score between zero and 1. The scoring of conservative substitutions is calculated, e.g., according to the algorithm of Meyers and Miller, Computer Applic. Biol. Sci., 4:11-17 (1988) e.g., as implemented in the program PC/GENE (Intelligenetics, Mountain View, Calif., USA).
[0118] As used herein, “percentage of sequence identity” means the value determined by comparing two optimally aligned sequences over a comparison window, wherein the portion of the polynucleotide sequence in the comparison window may comprise additions or deletions (i.e., gaps) as compared to the reference sequence (which does not comprise additions or deletions) for optimal alignment of the two sequences. The percentage is calculated by determining the number of positions at which the identical nucleic acid base or amino acid residue occurs in both sequences to yield the number of matched positions, dividing the number of matched positions by the total number of positions in the window of comparison and multiplying the result by 100 to yield the percentage of sequence identity. The term “substantial identity” of polynucleotide sequences means that a polynucleotide comprises a sequence that has at least 70% sequence identity, preferably at least 80%, more preferably at least 90% and most preferably at least 95%, compared to a reference sequence using one of the alignment programs described using standard parameters. One of skill will recognize that these values can be appropriately adjusted to determine corresponding identity of proteins encoded by two nucleotide sequences by taking into account codon degeneracy, amino acid similarity, reading frame positioning and the like. Substantial identity of amino acid sequences for these purposes normally means sequence identity of at least 60%, or preferably at least 70%, 80%, 90%, and most preferably at least 95%. Another indication that nucleotide sequences are substantially identical is if two molecules hybridize to each other under stringent conditions. However, nucleic acids which do not hybridize to each other under stringent conditions are still substantially identical if the polypeptides which they encode are substantially identical. This may occur, e.g., when a copy of a nucleic acid is created using the maximum codon degeneracy permitted by the genetic code. One indication that two nucleic acid sequences are substantially identical is that the polypeptide which the first nucleic acid encodes is immunologically cross reactive with the polypeptide encoded by the second nucleic acid. The terms “substantial Identity” in the context of a peptide indicates that a peptide comprises a sequence with at least 70% sequence identity to a reference sequence, preferably 80%, ore preferably 85%, most preferably at least 90% or 95% sequence identity to the reference sequence over a specified comparison window. Optionally, optimal alignment is conducted using the homology alignment algorithm of Needleman and Wunsch, J. Mol. Biol. 48:443 (1970). An indication that two peptide sequences are substantially identical is that one peptide is immunologically reactive with antibodies raised against the second peptide. Thus, a peptide is substantially identical to a second peptide, for example, where the two peptides differ only by a conservative substitution. Peptides which are “substantially similar” share sequences as noted above except that residue positions which are not identical may differ by conservative amino acid changes.
[0119] Methods of extraction of RNA are well-known in the art and are described, for example, in J. Sambrook et al., “Molecular Cloning: A Laboratory Manual” (Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., 1989), vol. 1, ch. 7, “Extraction, Purification, and Analysis of Messenger RNA from Eukaryotic Cells,” incorporated herein by this reference. Other isolation and extraction methods are also well-known, for example in F. Ausubel et al., “Current Protocols in Molecular Biology, John Wiley & Sons). Typically, isolation is performed in the presence of chaotropic agents such as guanidinium chloride or guanidinium thiocyanate, although other detergents and extraction agents can alternatively be used. Typically, the mRNA is isolated from the total extracted RNA by chromatography over oligo(dT)-cellulose or other chromatographic media that have the capacity to bind the polyadenylated 3′-portion of mRNA molecules. Alternatively, but less preferably, total RNA can be used. However, it is generally preferred to isolate poly(A)+RNA.
[0120] The method employs several basic steps to achieve its objective. First, a library of DNA TAGs is designed. The DNA TAG sequences are composed of random nucleotides. Each DNA TAG sequence, in one embodiment of approximately 60 bp in length, is unique among a plurality of TAG sequences, i.e. a specific TAG does not share sequence homology with any other TAG used simultaneously in the same assay and with any DNA or RNA molecule that will be labeled during the synthesis of the probe, regardless of the method used to synthesize the probe. The TAG sequences have similar physical properties so that a plurality of the TAG sequences can be used for hybridization under similar conditions. Second, pTAG-basic plasmids are constructed. Third, the TAG sequences are inserted into the pTAG-basic plasmids. Fourth, promoter array membranes are prepared. Fifth, promoter sequence candidates are inserted into the pTAG plasmids. Sixth, the pTAG plasmids with the promoter sequence candidate inserts are transfected into host cells, and the RNA extracted. The RNA or the resultant cDNA derived from the extracted RNA is then labeled, hybridized to the promoter array membrane, and analysis performed. Thus, the present disclosure discloses an array-based method for promoter detection and analysis. The method provides for transcriptional products that are tagged as they are synthesized, in such a way that one specific transcript is labeled with only one type of TAG, and one TAG labels only one type of transcript. All promoter sequence candidates are analyzed simultaneously in one reaction vial. The transcriptional output is analyzed on conventional arrays.
BRIEF DESCRIPTION OF THE DRAWINGS
[0121] FIG. 1 . Flow diagram of array-based promoter detection and analysis.
[0122] FIG. 2 . BrightStar-Plus membranes spotted manually (left) or using a robot (right) with a collection of reverse-strand TAG oligonucleotides.
[0123] FIGS. 3A and 3B . Comparative analysis of the activity of 42 promoters in a single population of HEK 293 cells. The 42 promoter-TAG plasmids and 8 promoter-less TAG-reporter plasmids were mixed in equimolar amounts and transfected into the same cell population. Total RNA was extracted 14 hours after transfection. RNA was labeled using the linear amplification method, and biotin-labeled probes were hybridized on the TAG-spotted membranes ( FIG. 3A ). Hybridization was revealed by chemiluminescence, and quantified by densitometry ( FIG. 3B ). The macro array membrane was made by spotting manually each oligonucleotide as a diagonal doublet.
[0124] FIGS. 4A and 4B . Comparison of the transcriptional activities of 92 promoters in a single cell population. The 92 promoter-TAG plasmids and 8 promoter-less TAG-reporter plasmids were mixed in equimolar amounts and transfected into the same cell population. Total RNA was extracted 14 hours after transfection. RNA was labeled using the linear amplification method, and biotin-labeled probes were hybridized on the TAG-spotted membranes ( FIG. 4A ). Hybridization was revealed by chemiluminescence, and quantified by densitometry (plain bars) ( FIG. 4B ). The relative luciferase activities obtained with each plasmid construct were obtained from previously published work and are shown at the bottom (empty bars) ( FIG. 4B ). The numbers at the bottom of the figure refer to the list of promoters described in Table 1. The luciferase data obtained with the various OM promoters (#59-73), defensin promoters (#74-85), and other promoters studied by Coleman (Coleman, S., et al. Experimental analysis of the annotation of promoters in the public database. Hum. Mol. Genet., 2002. 11(16): 1817-1821) were generated in different experimental conditions and should not be compared between each other. The macroarray membrane was made by spotting each oligonucleotide as a quadruplet, using a Biorobotics MicroGrid array spotting robot (Genomic Solutions, Ann Arbor, Mich.) at the microarray facility of the University of Idaho Environmental Biotechnology Institute (Moscow, Iowa).
[0125] FIGS. 5A and 5B . Validation of the Promoter Detective method with a set of 35 promoter-TAG plasmids. The autoradiogram ( FIG. 5A ) was obtained by hybridizing radioactive TAG-cDNA probes to a membrane spotted with the complementary TAG strands. The identity of the spots is indicated by numbers on the left side of the autoradiogram, and on the bottom of the bar chart ( FIG. 5B ). The bar chart summarizes the intensities of the various spots, relative to the signal obtained with the CMV promoter (=100).
[0126] FIG. 6 . Flow diagram for the construction of the pTAG reporter plasmid.
[0127] FIG. 7 . Plasmid map of the pTAG basic vector.
[0128] TABLE 1. List of 100 promoter sequences used within the examples. Each promoter is described with its symbol, length, and Refseq or GenBank accession number. The TAG identification number to which it is associated is also indicated.
DETAILED DESCRIPTION
[0129] The present disclosure provides a method for the detection and analysis of DNA promoter sequences. FIG. 1 provides a general flow chart. The disclosure provides for the construction of a vector library containing potential DNA promoter sequence candidates that may be present, for example, in a collection of nucleotide sequences, such as a genomic library, in computer-predicted promoter regions, or in deletion mutants of promoters under investigation, etc. Each clone generated potentially drives the transcription of a unique reporter gene composed of a well-defined, approximately 60-bp long DNA TAG composed of random nucleotides. The transcriptional properties of the various constructs are analyzed by pooling equimolar amounts of vectors and transfecting them into a cell line of interest. RNA is extracted, cDNA synthesized and labeled, directly or indirectly, and quantified by hybridization to the DNA TAGs arrayed on a membrane, glass, or bead support (see FIG. 1 for a general schematic diagram). Suitable bead compositions may include those used in peptide, nucleic acid and organic moeity synthesis, including but not limited to, plastics, ceramics, glass, polystyrene, methylstyrene, acrylic polymers, paramagnetic materials, thoria sol, carbon graphite, titanium dioxide, latex or cross-linked dextrans such as sepharose, cellulose, nylon, cross-linked micelles and teflon many all be used (see Microsphere Detection Guide, Bangs Laboratories, Fishers Ind.).
[0130] The design, operation and applications for the present disclosure will now be described in greater detail.
[0000] 1. Design of a Library of DNA TAGs that Will be Transcribed by the Putative DNA Promoter Sequences.
[0131] The TAG DNA sequences were DNA sequences composed of random nucleotides, that is each position had an equal probability of having any of the four deoxynucleotides (A, C, T, and G). Other bases, such as inosine, uracil, 5-methylcytosine, 8-azaguanine, 2,6-diaminopurine, 5 bromouracil, and other derivatives may be incorporated in their nucleotide form into the oligonucleotides. The length of the TAG sequence was short, preferably between about 16 bp to about 200 bp, although a shorter or longer length may be used, but typically about 60 bp. Within a plurality of TAG sequences, each TAG sequence had approximately equivalent amounts of the nucleotides A, T, G, and C such that each TAG sequence had approximately the same melting temperature as the other TAGs. A same melting temperature allowed for the unbiased quantification of various mRNAs by hybridization under the same temperature and ionic strength conditions. Within a plurality of TAG sequences, the nucleotide sequence of each individual TAG sequence was unique amongst the plurality of TAGs. Each TAG did not share sequence homology with any other TAG used simultaneously in the same assay and with any DNA or RNA molecule that was labeled during the synthesis of the probe, regardless of the method used to synthesize the probe. A 60 bp length of random nucleotides of the TAG sequence allowed for generation of a large number of unique TAGs that were highly unlikely to be found in nature. Additionally, the longer length of the TAG (e.g., about 60 bp) allowed for use of hybridization temperatures (e.g., 70° C.) that were high enough to prevent unspecific hybridization with partially homologous sequences. The GC content and thus melting temperature was normalized across the plurality of TAGs to ensure identical hybridization conditions for all of the TAG probes. To minimize cross-hybridization and for the highest specificity, all oligonucleotides were selected with a minimal length of sequence identity of no longer than six (6) bases. Low-complexity sequences with stretches of more than four (4) identical nucleotides were not allowed, thus avoiding difficulties in sequence similarity searching. Upon generation of the TAG sequences, the sequences were verified for the absence of homology amongst themselves. In some embodiments, the TAG sequences may be examined against sequences deposited in public databases such as GenBank, EMBL, DDBJ, and PDB using NCBI BLASTN to aid in determining if non-intended binding may occur. Oligonucleotides are generally synthesized as single strands by standard chemistry techniques, including automated synthesis. Many methods have been described for synthesizing oligonucleotides containing a randomized base. For example, a randomized position can be achieved by in-line mixing or using pre-mixed phosphoramidite precursors during an automated procedure (see, Ausbel et al., Current Protocols in Molecular Biology, Green Publishing, N.Y., 1995). Oligonucleotides are subsequently deprotected and may be purified by precipitation with ethanol, chromatographed using a size-exclusion or reversed-phase column, denaturing polyacrylamide gel electrophoresis, high-pressure liquid chromatography (HPLC), or other suitable method.
2. Construction of TAG-Plasmids
[0132] The TAG plasmids were derived from pTAG-basic ( FIG. 7 ). This plasmid incorporates a pair of SfiI sites which generate two distinct 3 nucleotide-long nonsymmetrical sticky ends suitable for the directional insertion of the TAG oligonucleotides. The plasmid also incorporates a modified cDNA encoding firefly luciferase (luc+). This 1650 bp cDNA was excised from the commercially available pGL3 using the restriction enzymes NcoI and XbaI. The wild-type coding region had been modified, in order to eliminate consensus sequences recognized by genetic regulatory proteins, thus helping to ensure that this reporter gene is unaffected by spurious host transcriptional signals. The plasmid also incorporates a 97 bp long α-globin 3′UTR. The high level stability of α-globin mRNA, with a half-life from 24 to 60 hours, is attributed to a C-rich cis element in its 3′UTR, to which a protein complex binds to stabilize the mRNA. This protein complex is highly conserved from mouse to human and is found in a wide spectrum of tissues and cell lines. This sequence is sufficient to increase luciferase mRNA stability, with a half-life of 7 hours. The plasmid also incorporates the SV40 polyA signal to efficiently polyadenylate the luciferase transcript, thus resulting in up to a five-fold increase of steady-state mRNA levels. The plasmid also incorporates a high copy number origin of replication from pUC19, but may alternatively contain a low copy number origin of replication, such as pBR322 Co1E1 ori/rop (15-20 copies per chromosome), pACYC177 p15A ori (10-12 copies per chromosome) or the CopyControl system (1, 10-50 copies per chromosome). Additionally, the plasmid incorporates the ampicillin and kanamycin resistance genes for selection of the pTAG derivatives in E. coli, the λ attP1 and attP2 sites for inserting promoter sequences by recombination using the Gateway system, and a MCS for inserting promoter sequence candidates by DNA ligation. The MCS was present in two structurally different but functionally equivalent copies flanking the ccdB gene, a configuration that allows for using the ccdB gene as a selection marker for plasmids that incorporates promoter sequences, by recombination or by ligation. The CcdB protein targets DNA gyrase and inhibits its catalytic reactions. Cells taking up unreacted vectors with the ccdB gene will not grow. The plasmid also incorporates a short, synthetic polyA signal based on the highly efficient polyA signal of the rabbit 13 -globin gene. Placed upstream of the MCS, it will terminate spurious transcription, which may initiate within the vector backbone.
[0000] 3. Insertion of DNA TAGs into pTAG-Basic
[0133] Typically, TAGs were obtained by annealing complementary 63 bp oligonucleotides [(+)strand: (N) 60 :ATA; (−)strand: (N) 60 :GTG] that are then ligated into SfiI digested pTAG-basic, although oligonucleotides of differing lengths can be used, preferably between about 16 bp to about 200 bp, more preferably between about 20 to about 150 bp, more preferably between about 30 to about 120 bp, more preferably between about 40 to about 100 bp, more preferably between about 50 to about 75 bp, and most preferably about 60 bp. The ligation reaction was electroporated into a host strain, for example E. coli DB3.1, which contains a gyrase mutation (gyrA462) that renders it resistant to the ccdB. Because the sticky ends generated by both SfiI sites are incompatible, a very low background of self-circularized pTAG-basic vectors, or vectors with multiple TAGs in tandem, was generated. The presence of the TAGs in the various plasmids was verified by DNA sequencing. High-throughput production of TAGs followed a similar methodology. Synthesis of 63 bp oligonucleotides was performed in two 96-well plates ((+) and (−) strands, respectively). The (+) and (−) strands were annealed in a 96-well plate, and ligated with SfiI digested, gel-purified pTAG basic. The ligation mixture was electroporated into electro-competent the E. coli DB3.1 host cells, using a 96-well electroporation plate. The bacterial clones were seeded into a 96-Deep-Well plate and the cultures were incubated for 18-24 hours at 37° C. at 250 rpm using a microtiter plate incubator shaker. Plasmid DNA purification was performed, either manually or via automation, for example using a BioRobot 3000 (Qiagen, Valencia, Calif.), and the presence of the TAGs verified via DNA sequencing (96-well format).
4. Preparation of Promoter Array Membranes
[0134] Oligonucleotide arrays were manufactured using nylon membranes. The (−) strand TAG oligonucleotides were synthesized in a 96-well plate format and resuspended in buffer, for example TE, pH 7.5, at a concentration of 100 μg/ml. Nylon membranes, for example Nytran SuPerCharge (Whatman PLC, Middlesex, UK), were cut (2 cm×4 cm) to fit 5.0 ml glass hybridization tubes. Oligonucleotides were either spotted manually in duplicate on the membranes (0.2 μg/spot) or oligonucleotide arrays printed using an array spotting robot, for example a Biorobotics MicroGrid (Genomic Solutions, Ann Arbor, Mich.). After spotting, the membranes were UV cross-linked twice using a Stratalinker 1800 at 120 mJ/sec, then baked at 70° C. for 1-2 hours. The printed membranes were sealed in parafilm and stored at −20° C. The quality of the membranes was validated by hybridizing 10% of the membranes with biotin-labeled (+) strand oligonucleotide TAGs. The 3′ end of the TAG oligonucleotides was labeled using terminal transferase and biotin-16-ddUTP. All TAGs were mixed together in equimolar amounts. The TAG mixture (100 pmol) was incubated in the presence of 1.0 nmol biotin-16-ddUTP and 50 U terminal transferase, following the manufacturer's recommendations. After a 15 minute incubation at 37° C., the end-labeled TAG probes were precipitated with LiCl, centrifuged and resuspended in ddH 2 O. The labeling efficiency was checked by spotting a serial dilution of the labeling reaction and a standard on the nylon membrane. Detection was performed by chemiluminescence, for example with alkaline phosphatase-conjugated streptavidin, following the manufacturer's recommendations. Quantification was performed by densitometry. Upon validation of the quality of the biotin-labeled probes, the quality of the arrays was assessed by hybridizing the probes to the membranes using standard procedures, detecting them by chemiluminescence, and measuring the intensity of each spot by densitometry. The membranes were accepted upon observation of less than a variation of 5% of intensity and spot size.
5. Construction of Promoter-TAG Plasmids
[0135] Promoter sequence candidates were inserted into TAG plasmids using two methods. First, promoter sequence candidates were extracted from existing plasmids using endonucleases such as restriction enzymes and inserted into the pTAG plasmids, between sites located in the multiple cloning sites. Promoter sequence and pTAG plasmids were assembled by DNA ligation using standard protocols (see Crowe et al., Improved cloning efficiency of polymerase chain reaction ( PCR ) products after proteinase K digestion. Nucleic Acids Res. Jan 11, 1991; 19(1):184); Ausubel, F. M., et al., Short Protocols in Molecular Biology ). Alternatively, promoter sequences were amplified by PCR, using primers carrying attB1 and attB2 extensions, and using mammalian genomic DNA or other plasmids as templates. The PCR products were inserted into the pTAG plasmids using the Gateway® recombination system. A promoter sequence candidate may be provided by a computer-predicted model, DNA fragments from a collection of nucleotide sequences, such as a genomic library, deletion or site-directed mutants of a specific promoter, tissue-specific promoters, artificial promoters, etc. Clones containing the pTAG plasmids with the promoter inserts were cultured in LB medium in the presence of 50 μg/ml ampicillin or 25 μg/ml kanamycin. At various time points during cell growth, aliquots of each culture were taken, the cell density measured spectrophotometrically at 600 nm, and equal volumes of culture pooled. Plasmid DNA was extracted using an alkaline lysis method and purified using anion-exchange resin. In order to verify that all plasmids were present in the mixture in equimolar concentrations, the following manipulation was performed. All plasmids in the DNA mixture were linearized by restriction digestion, and separated on an agarose gel (0.7%). The resultant DNA fragments, with sizes ranging from 5 to 15 kb, were stained with ethidium bromide and quantitated by densitometry using a gel documentation system. The linearity of the assay was verified by quantifying serial dilutions of the plasmid restriction digestion.
6. Transfection and RNA Extraction
[0136] The purified plasmid DNA mixture containing equimolar amounts of the promoter plasmids was transfected into HL60, U937, and 293 cell lines. Per transfection, 1×10 7 viable U937 cells were washed and resuspended in 0.4 ml RPMI medium. Plasmid DNA (20 μg) was added and the cell/DNA suspension was mixed gently by inversion. After a 5 minute incubation at 25° C., the cells were electroporated using a BTX ECM-600 electroporator with the following settings: 500 V capacitance and resistance, 950 μF capacitance, 186 ohms resistance, 200 V charging voltage. After the electrochoc, the cells were transferred into a 10 cm diameter tissue culture dish containing 10 ml RPMI medium supplemented with 10% FBS. After 2 to 5 hours incubation at 37° C., cells were harvested by centrifugation at 10 krpm for 30 seconds. Cell pellets were lysed by addition of 300 μl Trizol reagent and total RNA was extracted according to the manufacturers protocol (Invitrogen, Carlsbad, Calif.) (see also Current Protocols in Molecular Biology, John Wiley & Sons). RNA was precipitated with isopropyl alcohol, resuspended in RNase-free TE, pH 7.5, and quantified by measuring the absorbance at 260 nm and 280 nm (ratio ˜2). RNA integrity was verified by agarose gel electrophoresis and ethidium bromide staining. The 28S and 18S rRNAs, represented in discrete individual bands, had a 2:1 intensity ratio. RNA samples with a visible degree of degradation were not further processed. In parallel, an equimolar mixture of promoter-less TAG plasmids were transfected and analyzed for mRNA expression using the array. This control detected the possible presence of cryptic promoter activity in the TAGs. The promoter-less TAG plasmids yielding above-background signals were discarded.
7. Labeling, Hybridization, and Detection
[0137] Radioactive cDNA probes were synthesized from total RNA. The total RNA was purified with Trizol (Invitrogen) and the concentration of the RNA was determined by the OD260 reading. One to five microgram of total RNA was mixed with MA5-a oligo (5′-TAGTCACTTCGATCGCTGAGG-3′) ([SEQ ID NO. 1]), and the nucleotides dATP, dTTP, dGTG, and 32P-dCTP. The reaction was incubated at 80° C. for 3 minutes and then cooled to 42° C. Then added were 10× reverse transcription buffer (NEB), RNAse inhibitor, and M-MuLV reverse transcriptase (NEB). The reaction was mixed and incubated at 42° C. for 60 minutes, then denatured at 90° C. for 10 minutes.
[0138] The radioactive probes were hybridized to the membrane using Ultrahyb-oligo hybridization buffer (Ambion, Inc.) at 60° C. overnight. After washing the membrane twice with 2×SSC/1% SDS and twice with 1×SSC/1% SDS at 60° C., the bound probes were detected by autoradiography, using for example, Kodak Biomax Light Film (Carestream Health, Inc., New Haven, Conn.). The density of each spot was quantified with computer software, for example, Kodak 1D Image Analysis Software (Carestream Health, Inc., New Haven, Conn.).
[0139] In an alternate embodiment, biotin-labeled cDNA probes were synthesized from the total RNA. The probes were synthesized using the AmpoLabeling-LPR method developed by SuperArray Bioscience Corporation. This method increased the sensitivity of cDNA arrays by amplifying the cDNAs obtained by reverse transcription by up to 30 rounds of Linear Polymerase Replication (LPR). A 300 nucleotide long region from the 5′ end of the luciferase mRNAs, encompassing the 60 nucleotide TAGs, was reverse transcribed and amplified in the presence of biotin-labeled dUTP. The total RNA was annealed with primer complementary to the MA4 segment, in a thermal cycler at 70° C. for 3 minutes, cooled to 37° C. and incubated at 37° C. for 10 minutes. The annealed product was reverse transcribed using MMLV reverse transcriptase in presence of RNasin Ribonuclease Inhibitor. After inactivation of the reverse transcriptase and RNA hydrolysis at 85° C., the cDNAs were amplified by LPR with primer 5′-GGCTCGGCCTCTGAGCTAAT-3′ ([SEQ ID NO. 2]) located immediately upstream of the TAG, in the presence of biotin-16-dUTP, and a thermostable DNA-dependent DNA polymerase, using the following program: 85° C. for 5 minutes; then 30 cycles of 85° C. for 1 minute, 50° C. for 1 minute, 72° C. for 1 minute; followed by 72° C. for 5 minutes. The probe was then checked for biotin incorporation by making serial dilutions of the probe synthesis reaction, spotting 1 μl aliquots on a HyBond nylon membrane and detecting the probe using the ECL chemiluminescent detection kit. Probes that were detectable at 1000-fold dilutions or higher were used in the hybridizations.
[0140] The hybridization of the biotinylated probes to the membranes was performed using the Ultrahyb-oligo hybridization buffer (Ambion Inc.), at 60° C. overnight. After washing the membrane twice with 2×SSC, 1% SDS and twice with 1×SSC, 1% SDS at 60 C, the bound probes were detected by chemiluminescence using a streptavidin-alkaline phosphatase conjugate and following the manufacturer's protocol (CDP-Star Universal Detection Kit, Sigma). The image was acquired with a Kodak image station 440 for 1 hour ( FIG. 3A , FIG. 4A , and FIG. 5A ). The density from each spot was quantified using the Kodak ID Image Analysis software. The data presented in FIGS. 3A and 3B and FIGS. 4A and 4B show that: a) all the “blank” reporter-TAG plasmids which lack promoter sequences (#10, 19, 26, 28, 30, 35, 39, and 47 in Table 1) give very low intensity signals, a fact, which suggests the absence of intrinsic promoter activity from the plasmid backbone; b) with the series of defensin promoters (#74-85), the clone expressing the highest mRNA level (#79) is also the one expressing the highest level of luciferase. The data presented in FIGS. 5A and 5B show that: a) as expected, the viral CMV promoter appeared to be the strongest, a fact, which is well-documented in the scientific literature (U.S. Pat. Nos. 5,168,062 and 5,385,839; Cayer et al J Immunol Methods. Apr. 30, 2007;322(1-2):118-27; Sakurai et al Gene Ther. October 2005;12(19):1424-33; Fabre et al. J Gene Med. May 2006;8(5):636-45.); b) The GAPDH (glyceraldehyde-3-phosphate dehydrogenase) promoter was able to drive very high expression levels, which is consistent with observation made by others (Hirano T et al, Biosci Biotechnol Biochem. 1999;63(7):1223-7; Punt P J et al. Gene. 1990; 93(1):101-9; Nagashima T et al., Biosci Biotechnol Biochem. 1994;58(7):1292-6); c) the ferritin light-chain promoter was about 40% stronger than the Ferritin heavy chain promoter, a fact that supports findings made by Cairo et al. in rat liver (Biochem J. 1991; 275 (Pt 3):813-6); d) Promoters OM3 (TAG61) and Def6 (TAG77) produced the strongest hybridization signals in their respective groups (OM and Defensin promoters), a fact, which correlates with the luciferase activities determined previously (Ma et al., Nucleic Acids Res. 1999;27(23):4649-57; Ma et al. J Biol Chem. Apr. 10, 1998;273(15):8727-40.). Taken altogether, these data validate the present disclosure compared to other methods.
[0141] The following examples are offered by way of illustration, and not by way of limitation.
EXAMPLES
Example 1
Construction of 100 pTAG-Reporter Plasmids
[0142] One hundred pTAG-plasmids featuring a multiple cloning site (MCS), attP sequences, a ccdB gene, a T7 promoter, a unique 60 bp-long reporter TAG, a specific MA4 segment, a 3-frame translation stop codon, a hemoglobin RNA stabilization fragment and a poly-A signal were constructed. The construction was performed in 6 steps ( FIG. 6 ). First, a partial MCS was inserted, between the SfiI sites of plasmid pGL4 (Promega, Madison, Wis.). All the cloning sites from the original pGL4 plasmid were deleted and replaced with EcoRI, KpnI, SacI, NheI, XhoI, BgIII sites, and followed by two sets of SfiI/BgII sites separated by a CG dinucleotide. The two sets of SfiI sites allowed for the directional insertion of TAG sequences. The dinucleotide CG between the SfiI sites created a unique restriction site (SmaI/XmaI), which revealed useful to facilitate plasmid digestion with SfiI, either by insertion of a 170 bp-long spacer fragment to dissociate both SfiI sites, or by digestion of the plasmid sequentially with SmaI and then SfiI.
[0143] In the second step, a second partial MCS was inserted between the XhoI and BglII sites of pGL4-12. The resulting plasmid (pGL-1256) contained BglII, ApaI, NruI, KpnI, XhoI SacI, BglII, NheI, EcoRV, and MluI sites following the existing MCS. As a result, pGL-1256 contained two structurally different but functionally equivalent MCS surrounding the ApaI and NruI sites, a feature useful for cloning promoter sequence candidates in the TAG-plasmids. In the third step, the sequence encoding the luciferase reporter gene (NcoI-XbaI fragment) was replaced with an 80-mer oligonucleotide which contained a specific 25 bp-long sequence (MA4), a three-frame translation stop codon, and a RNA stabilization sequence derived from human alpha globin gene. The MA4 facilitated the synthesis of TAG-specific probes from mRNAs.
[0144] In the fourth step, the resulting plasmid 1256MA4 was digested with EcoRV and MluI, which allowed for insertion of an oligonucleotide that contained the bacteriophage T7 RNA polymerase promoter sequence. The presence of the T7 promoter allowed for synthesis of biotinylated RNA probes by in vitro transcription, a method which increased the sensitivity of the assay by at least one order of magnitude.
[0145] In the fifth step, the Gateway® sequences attP—ccdB—chloramphenicol-resistance gene were amplified by PCR using plasmid pDONR-201 as template (Invitrogen Inc., Carlsbad, Calif.) and the following primers: sense-tcgggccccaaataatgattttattttgactgatag [SEQ ID NO. 3] and antisense-atgggcccaaataatgattttattttgactgatagtgacctgttc [SEQ ID NO. 4]. The PCR product was inserted into the ApaI site of plasmid 1256MA4T7, generating plasmid 1256MA4T7att. Finally, plasmid 1256MA4T7att was digested with BglI and 60 bp-long ds oligonucleotides (TAG) were directionally inserted into the plasmid. In total, we created 100 reporter plasmids—pTAG-Reporter 1 to 100. These plasmids were used to generate the 92 promoter-TAG plasmids. The remaining 8 pTAG-Reporter plasmids were used as blank.
[0146] These 100 pTAG-Reporter plasmids are used for cloning putative promoters into the MCS, using either conventional methods (restriction digestion and ligation), or the GATEWAY® technology with attB-modified PCR products.
Example 2
Manual and Robotic Production of Macro-Array Membranes
[0147] First, three nylon membranes: BrightStar-Plus (Ambion Inc., Austin, Tex.), Tropilon-Plus (Applied Biosystems, Foster City, Calif.), and Nytran SuperCharge (Whatman PLC, Middlesex, UK) were compared for their ability in being printed with short oligonucleotides. The 63 bp-long oligonucleotides complementary to the TAGs present on the TAG-reporter plasmids were manually spotted on the membranes, and hybridized with the biotin end-labeled sense TAG oligonucleotides. BrightStar-Plus (Ambion Inc., Austin, Tex.) was selected for use in subsequent experiments as this membrane produced the best results in terms of low background, sharpness of the signal spots, and the observation the rough surface of the BrightStar-Plus membrane produced stronger signals than the smooth surfaces of the other two membranes, without increasing the background. The nylon membranes were cut (2×4 cm) to fit 5-mL glass hybridization tubes and the 8-well hybridization plates (SuperArray Inc., Frederick, Md.).
[0148] Next, the amount of oligonucleotides to be spotted on the membrane was optimized. Stock solutions for all the reverse strand TAG oligonucleotides were made by reconstituting the lyophilized products in TE pH 7.5 to 100 μM. Serial dilutions of 20×, 60×, 180×, 540× and 1620× were made. Using a 2 μL Pipetman, the diluted oligonucleotides (0.2 μl) were spotted manually, in duplicate, on the membrane. Following hybridization of the membrane with biotin end-labeled sense-strand TAG oligonucleotide probes, detection of the signals was performed by chemiluminescence using the Southern-Star kit (Applied Biosystems, Foster City, Calif.). The 20-fold dilutions produced a strong and clean signal spots, and were selected.
[0149] The same diluted oligonucleotides (n=100) ( FIG. 2 ) were printed using a Biorobotics MicroGrid array spotting robot (Genomic Solutions, Ann Arbor, Mich.) at the microarray facility of the University of Idaho Environmental Biotechnology Institute (Moscow, Iowa). Each oligonucleotide was printed as a quadruple spot. Both types of membranes were air-dried at room temperature for 10 min and then UV-crosslinked twice using a Stratalinker 1800 (Stratagene) at 120 mJ/sec, then baked at 70° C. for 2 hours. The printed membranes were then sealed in parafilm and stored at 4° C. The size of the membrane was designed to fit into convenient small containers such as 2-mL microcentrifuge tubes and 8-well plates.
Example 3
Cloning of 92 Human and Viral Promoter Sequences into the TAG-Reporter Plasmids
[0150] Ninety-two human and viral promoter sequences (TABLE 1) were cloned into the TAG-reporter plasmids using the Gateway® system. They included 12 defensin promoters and 15 Oncostatin M promoters, 57 genomic DNA fragments from both EPD and chromosome 21, which have been studied experimentally for promoter activity, and 8 well-known promoters (SV40, CMV, wild-type and mutant RSV, GAPDH, HSP, FerL, and FerH). First, the promoter sequences were amplified by PCR, using human chromosomal DNA or plasmids as templates, and primers carrying attB sequence extensions. The PCR products were inserted into the pTAG-reporter plasmids in place of the ccdB and chloramphenicol-resistance genes by in vitro recombination using the BP clonase (Invitrogen, Carlsbad, Calif.). The recombinant plasmids were introduced into E. coli Top10 using the heat-shock procedure, and amplified. Recombinant clones lacking promoter inserts were obtained at a frequency of about 1:200. To ascertain the correct clones, the plasmid DNAs of each clone were prepared and analyzed by agarose gel electrophoresis separately. Plasmid DNAs were quantified by spectrophotometry. Finally, equimolar amounts were pooled at a final concentration of 0.4 μg DNA/μL.
[0151] In the context of screening plasmid libraries of putative promoters, E. coli clones are arrayed in 96-well plates. The bacteria (not their plasmid DNA) are pooled and amplified in the same flask. Their plasmid DNA is purified in a single preparation, before being transfected into the same cell population.
Example 4
Testing the Promoter Detective Method with 92 Promoter-TAG Plasmids
[0152] The method was performed with the 92 promoter-TAG and 8 blank reporter-TAG plasmids. Different amounts (4, 16, 64 μg) of equimolar mixtures of these plasmids were transfected into HEK 293 cells using Lipofectamine 2000 (Invitrogen, Carlsbad, Calif.). After 14 and 25 hours culture at 37° C., cells were harvested. Total RNA was extracted and purified using the TRIzol-based method (Invitrogen, Carlsbad, Calif.). Biotin labeled cDNA probes were synthesized from the total RNA. The probes were synthesized using the AmpoLabeling LPR method (SuperArray Bioscience Corp., Frederick, Md.). The sensitivity of cDNA arrays was increased by amplifying the cDNAs obtained by reverse transcription by up to 30 rounds of Linear Polymerase Replication (LPR). A 300 nucleotide long region, encompassing the 60 nucleotide TAGs, was reversed transcribed and amplified in the presence of biotin labeled dUTP. The 2.5 μg total RNA was annealed with primer complementary to the MA4 segment, in a thermal cycler at 70° C. for 3 minutes, cooled to 37° C. and incubated at 37° C. for 10 minutes. The annealed product was reverse transcribed using MMLV reverse transcriptase and RNA hydrolysis at 85° C., the cDNAs were amplified by LPR with primer 5′-GGCTCGGCCTCTGAGCTAAT-3′ [SEQ ID NO. 2] located immediately upstream of the TAG, in the presence of biotin 16 dUTP, and a thermostable DNA dependent DNA polymerase, with the following program: 85° C. for 5 minutes; then 30 cycles of 85° C. for 1 minute; 50° C. for 1 minute; 72° C. for 1 minute; followed by 72° C. for 5 minutes. The probe was then checked for biotin incorporation by making serial dilutions of the probe synthesis, spotting 1 μl aliquots onto a HyBond nylon membrane (Amersham, Little Chalfont, UK) and detecting the probe using the ECL chemiluminescent detection kit. Probes detectable at 1000-fold dilutions or higher were used in the hybridizations.
[0153] The hybridization of the biotinylated probes to the membranes was performed using the Ultrahyb-oligo hybridization buffer (Ambion Inc.), at 60° C. overnight. After washing the membrane twice with 2×SSC, 1% SDS and twice with 1×SSC, 1% SDS at 60 C, we detected bound probes by chemiluminescence using a streptavidin-alkaline phosphatase conjugate and following the manufacturer's protocol (CDP-Star Universal Detection Kit, Sigma). The image was acquired with a Kodak image station 440 for 1 hour ( FIG. 4A ). The density from each quadruple spot was quantified using the Kodak ID Image Analysis software. The results indicate: a) all the “blank” reporter-TAG plasmids which lack promoter sequences (#10, 19, 26, 28, 30, 35, 39, and 47 in Table 1) give very low intensity signals, a fact, which suggests the absence of intrinsic promoter activity from the plasmid backbone; b) with the series of defensin promoters (#74-85), the clone expressing the highest mRNA level (#79) is also the one expressing the highest level of luciferase.
Example 5
Testing the Promoter Detection Method with 35 Promoter-TAG Plasmids
[0154] The method was tested with a set of 35 promoter-TAG plasmids. Twenty μg of an equimolar mixture of these plasmids were transfected into U937 cells by electroporation. After 7 hours culture at 37° C., cells were harvested. Total RNA was extracted and purified using the TRIzol-based method (Invitrogen. Carlsbad, Calif.), and quantified by spectrophotometry (Abs260 nm).
[0155] Radioactive cDNA probes were synthesized as follows. One microgram total RNA in 6.3 μL H 2 O was mixed with 0.7 μL of 100 μM MA5-a oligonucleotide (5′-TAGTCACTTCGATCGCTGAGG-3′) ([SEQ ID NO. 1]), 1.1 μL of 5 mM each of dATP/dTTP/dGTG, and 1.9 μL 32 P dCTP. The reaction mixture was heated to 80° C. for 3 minutes and then cooled down to 42° C. Then 1.5 μL 10× reverse transcription buffer (New England Biolabs), 0.75 μL RNAse inhibitor, and M-MuLV reverse transcriptase (New England Biolabs) were added, and the reaction was performed at 42° C. for 60 minutes. The probes were then denatured at 90° C. for 10 minutes.
[0156] The hybridization of the radioactive probes to the membranes was performed using the Ultrahyb-oligo hybridization buffer (Ambion Inc.), at 60° C. overnight. After washing the membrane twice with 2×SSC, 1% SDS and twice with 1×SSC, 1% SDS at 60° C., bound probes were detected by autoradiography using a Kodak Biomax Light film. The density of each spot was quantified using the Kodak 1D Image Analysis software ( FIGS. 5A and 5B ) where the autoradiogram was obtained by hybridizing radioactive TAG-cDNA probes to a membrane spotted with complementary TAG strands. The intensities of the various spots were compared, relative to the signal obtained with the CMV promoter. As expected, the viral CMV promoter appeared to be the strongest, a fact, which is well-documented in the scientific literature (U.S. Pat. Nos. 5,168,062 and 5,385,839; Cayer et al J Immunol Methods. Apr. 30, 2007;322(1-2):118-27; Sakurai et al Gene Ther. October 2005;12(19):1424-33; Fabre et al. J Gene Med. May 2006;8(5):636-45.). The GAPDH (glyceraldehyde-3-phosphate dehydrogenase) promoter was able to drive very high expression levels, which is consistent with observation made by others (Hirano T et al, Biosci Biotechnol Biochem. 1999;63(7):1223-7; Punt P J et al. Gene. 1990; 93(1):101-9; Nagashima T et al., Biosci Biotechnol Biochem. 1994;58(7):1292-6). Also, the ferritin light-chain promoter was about 40% stronger than the Ferritin heavy chain promoter, a fact that supports findings made by Cairo et al. in rat liver (Biochem J. 1991; 275 (Pt 3):813-6). Promoters OM3 (TAG61) and Def6 (TAG77) produced the strongest hybridization signals in their respective groups (OM and Defensin promoters), a fact, which correlates with the luciferase activities determined previously (Ma et al., Nucleic Acids Res. 1999;27(23):4649-57; Ma et al. J Biol Chem. Apr. 10, 1998;273(15):8727-40.). Taken altogether, these data validate the present disclosure compared to other methods.
[0000]
TABLE 1
Gene
Promoter
Refseq or
TAG #
symbol
size (bp)
Accession #
1
MT1B
471
M13484
2
PROC
495
NM_000312
3
MMP1
477
NM_002421
4
CEA
508
NM_002483
5
GAS
539
NM_000805
6
H3FL
506
NM_003537
7
RUN3
356
K00777
8
SLC9A1
509
XM_046881
9
ADAMTS1
560
NM_006988
10
Blank
11
CCT8
528
NM_006585
12
CRYZL1
583
NM_005111
13
DAF
557
NM_000574
14
GABPA
611
NM_002040
15
IFNAR1
667
NM_000629
16
KRT1
520
NM_006121
17
LHB
494
NM_000894
18
NEFL
495
NM_006158
19
Blank
20
NEG9
407
N/A
21
IVL
500
NM_005547
22
APOE
509
NM_000041
23
C21ORF33
689
NM_004649
24
DSCR4
688
NM_005867
25
FTCD
596
NM_006657
26
Blank
27
ITGB2
647
NM_000211
28
Blank
29
TFF1
605
NM_003225
30
Blank
31
WRB
639
NM_004627
32
AMY2B
488
NM_020978
33
BCKDHA
481
NM_000709
34
CA3
518
NM_005181
35
Blank
36
H4FG
222
NM_003542
37
NEG13
376
N/A
38
NEG18
503
N/A
39
Blank
40
NEG21
444
N/A
41
NEG22
418
N/A
42
NEG23
259
N/A
43
NEG2
285
N/A
44
NEG3
460
N/A
45
NEG5
488
N/A
46
NEG7
466
N/A
47
Blank
48
RNU4C
305
M15957
49
SH3BGR
588
NM_007341
50
NEG19
483
N/A
51
SV
330
N/A
52
CMV
655
N/A
53
RSV
396
N/A
54
RSV303
396
N/A
55
GAPDH
532
N/A
56
HSP
464
N/A
57
FerL
270
N/A
58
FerH
180
N/A
59
OM1 (pGL3BomB1)
189
BC011589
60
OM2 (N1)
304
BC011589
61
OM3 (3STAT)
300
BC011589
62
OM4 (3STATm)
300
BC011589
63
OM5 (3STATmm)
300
BC011589
64
OM6 (N1 ApI)
304
BC011589
65
OM7 (N1 SpI mutation)
304
BC011589
66
OM8 (N1 3STATmm)
304
BC011589
67
OM9 (RI)
194
BC011589
68
OM10 (StuI)
94
BC011589
69
OM11 (2STATm)
194
BC011589
70
OM12 (N1 2STATmm)
304
BC011589
71
OM13 (1STAT)
109
BC011589
72
OM14 (1STATm)
109
BC011589
73
OM15 (TATA)
31
BC011589
74
Def3 (B/3)
619
AA321199
75
Def4 (AvaI)
497
AA321199
76
Def5 (HincII)
321
AA321199
77
Def6 (HinfI)
299
AA321199
78
Def7 (ApoI)
203
AA321199
79
Def8 (Sau96I (7))
164
AA321199
80
Def9 (ScrfI (9))
144
AA321199
81
Def10 (ScrfI (TATA))
144
AA321199
82
Def11 (Tru9I)
111
AA321199
83
Def12 (Tru9ITATA)
111
AA321199
84
Def13 (Tru9ITATAm)
111
AA321199
85
Def14 (Tru9ITATAm2)
111
AA321199
86
ALB
517
NM_000477
87
NEG11
468
N/A
88
HLCS
645
NM_000411
89
NEG12
522
N/A
90
NEG1
500
N/A
91
NEG6
480
N/A
92
ORM1
499
NM_000607
93
PKNOX1
593
NM_004571
94
USP16
581
NM_006447
95
IGSF5
622
AF121782
96
NEG10
406
N/A
97
NEG16
202
N/A
98
NEG17
339
N/A
99
PCP4
625
NM_006198
100
TCRD
333
M21624 | The present disclosure discloses an array-based method for promoter detection and analysis. Promoter sequence candidates are analyzed simultaneously in one reaction vial utilizing a vector comprising a TAG sequence wherein transcriptional products are tagged as they are synthesized, in such a way that one specific transcript is labeled with only one type of tag, and one tag labels only one type of transcript. The transcriptional output is analyzed on conventional arrays. | 2 |
BACKGROUND
The present invention relates to mechanical actuators. More particularly, the present invention is applied in conjunction with high force, low travel linear actuators.
Actuators, such as high output force actuators are well known in the art. Some high output force actuators are motor or gear box driven, such as a ball screw actuator with a high ratio motor/gear box drive. Others are pneumatic, hydraulic or thermochemically driven. Thermochemical actuators usually employ a thermally expansible medium or compound, such as a wax, to extend a piston and thereby drive an external device.
Examples of the actuators are disclosed in U.S. Pat. No. 5,025,627 (Schneider). U.S. Pat. No. 5,396,770 (Petot et al.), U.S. Pat. No. 5,020,325 (Henault), U.S. Pat. No. 5,685,149 (Schneider et al.), U.S. Pat. No. 5,738,658 (Maus et al.), U.S. Pat. No. 5,720,169 (Schneider), U.S. Pat. No. 5,419,133 (Schneider), and U.S. Pat. No. 5,222,362 (Maus et al.), the disclosures of which are whereby incorporated by reference in their entirety.
These thermochemical actuators are described with various nomenclature including heat motors, thermochemical actuators, mechanical actuators, electrothermal actuators, high output paraffin actuators (HOP actuators), pneumatic actuators, hydraulic actuators, and the like. All of these devices actuate a shaft in response to heat energy. The heat is applied to a variable volume chamber filled with a working medium such as wax or fluid. The working medium expands, thus expanding the chamber volume and driving the shaft or piston. The motion of the shaft can be used to drive various external devices. These actuators are utilized in various applications including automotive systems and satellites. Wax actuators are used in automobile radiators to open a water circulation valve when the engine reaches operating temperature.
For example, high output paraffin (HOP) actuators are made by Starsys, Inc. in Boulder, Colo. They use paraffin, or wax, as an actuating technique by utilizing the about 15% volume expansion that occurs when paraffin melts. The volume expansion increases the hydrostatic pressure in a pressure housing, applying that pressure to a rubber boot that squeezes an output rod out of the HOP housing.
When using such actuators, it is absolutely essential to have an external means of removing power to stop heating of the paraffin when the actuator stroke is complete or whenever the output rod has reached an immovable external stop. Otherwise, the pressure in the actuator housing will continue to increase, destroying the actuator. However, if the means to remove power does not function properly or fast enough, the actuator may be destroyed. There is a need for a means of absorbing the increase in pressure in the actuator even if the power supply is not removed.
The most commonly used means for heating the paraffin or wax is an electrical heater. Some techniques for removal of power include using a position sensor, such as a microswitch or reed switch, to sense the end of stroke and, either directly or indirectly, interrupt power to the actuator heaters. As soon as power is removed, the actuator output rod starts to retract, the position sensor again applies power to the actuator, and this cycle continues until power is removed from the circuit. A drawback to this technique is that, if the actuator output rod encounters an obstruction, either intentional or unintentional, before it reaches its planned end of stroke, the switch at the end of stroke is not triggered, and the actuator will be destroyed.
Many users of paraffin actuators have, at one time or another, damaged an actuator through inadvertent mishandling while testing various systems. Specifically, if one leaves the power applied to the internal heaters after (a) the output rod has reached the end of its travel or (b) the output rod has met an immovable obstruction such as the end of travel of the adjacent components, the internal pressure in the paraffin chamber increases to a point where internal parts of the actuator fail in accordance with design, preventing external release of the wax. This failure requires the return of the actuator to the manufacturer for repairs at significant cost.
When such actuators are utilized in aircraft or spacecraft, it becomes more important to provide a means for eliminating actuator failure resulting from pressure buildup. Additionally, when such actuators are used in remote applications, such as orbiting satellites, failure of the actuator may result in the loss of the satellite, discharge of the expanding medium on other parts of the satellite, destruction of the piston or actuation rod, or other damage to the satellite system. This damage can occur when the power removal mechanism fails or when external heat is applied other than from the intended power source. Additionally, when used in such remote applications, it is desirable to be able to reuse the actuator after such failure or pressure build-up.
Accordingly, there is a need for a system that would eliminate failure of the actuator due to pressure buildup even if the power supply to the actuator is maintained.
Additionally, there is a need for a system that eliminates failure of the actuator due to pressure buildup, by allowing the piston or actuator rod to travel its full path even in the face of an obstruction.
There is also a need for a thermochemical actuator that is reusable even after excessive pressure triggers a release mechanism.
There is also a need for an actuator safety mechanism for an actuator that can be triggered without any external input or power.
SUMMARY
The present invention is directed to a mechanical actuator apparatus that satisfies the above mentioned needs. An actuator having features of the present invention comprises a body, a thermally responsive expansion material contained in the body, and an element, such as a piston or a rod, that is movable with respect to the body of the actuator and performs a function. The body of the actuator is attached to whatever larger apparatus that it forms a part of through a mounting mechanism that allows the movement of the body relevant to the moving element in response to preset conditions in the body of the actuator. These preset conditions could be related to a threshold pressure, temperature, or moving force of the actuator arm or piston. In a preferred embodiment, the mounting mechanism is a linear slide, spring-loaded against a stop and attached to the body of the actuator wherein the slide retracts when output force exceeds the spring preload.
In yet another preferred embodiment, a microswitch or a break to the power supply is included in the mounting mechanism such that the power to the actuator heater is removed when the slide retracts.
An advantage of the present invention is that it eliminates failure of the actuator due to pressure buildup even if the power supply to the actuator is maintained after the maximum actuator force is achieved.
Another advantage of the present invention is in providing a system that eliminates failure of an actuator due to pressure buildup, by allowing the piston or actuator rod to travel its full path even in the face of an obstruction.
Another advantage of the present invention is in providing a thermochemical actuator that is reusable after excessive pressure triggers a release mechanism.
Yet another advantage of the present invention is providing a safety mechanism for an actuator that can be triggered without any external input or power.
These and other features, aspects, and advantages of the present invention will become better understood with reference to the following drawings, description, and appended claims.
DRAWINGS
The FIGURE shows an embodiment of the invention wherein a spring-loaded slide mechanism is utilized as part of a thermal actuator system.
DESCRIPTION
The present invention is applicable to any system utilizing any high output force actuator that could be damaged by overloading. While one version of the present invention will be described in conjunction with thermochemical actuators, and particularly high output paraffin actuators, it is applicable to other high output force actuators, such as a ball screw actuator with a high ratio motor/gear box drive. Other mechanical, pneumatic, hydraulic and thermal actuators are utilized.
In accordance with the embodiment shown in the FIGURE, a high output paraffin (HOP) actuator 11 is shown. It should be understood that the actuators contemplated in the present invention are part of a larger structure, such as a satellite system, wherein the actuator is triggered to perform one function within the larger structure. Operations of HOP actuators are well known in the art and are available commercially from various vendors.
For example, a HOP actuator useful in the present invention comprises a chamber which has a passage through which a piston or extensible member is slidably received. An expandable medium, such as a wax, fills the chamber. The wax expands significantly as it changes phase from solid to liquid. Wax, for example, commonly increases from 12 to 15% in volume as it changes from its solid to liquid state.
A temperature changing means, such as a Peltier effect thermoelectric heating/cooling chip, selectively adds and removes heat from the expandable medium in the chamber. When connected with a source of electricity of one polarity, the Peltier effect chip heats its surface closest to the chamber to transmit heat energy into the wax. When connected with the opposite polarity, the Peltier chip draws heat from its face against the chamber and discharges the heat through cooling fins. For speed of operation, it is advantageous to hold the expandable medium substantially at its melting temperature.
When thermal energy is applied to room temperature wax, the wax retains its solid form but increases in temperature until it reaches its melting point. The additional energy necessary to change the wax from the solid to liquid phase is supplied by the application of additional thermal energy. However, the absorbed thermal energy causes an isothermal phase change rather than increasing the temperature of the wax until the phase change is completed. If additional thermal energy is applied after the phase change, the liquid wax would increase in temperature. When thermal energy is removed, the liquid wax isothermally solidifies. In this manner the wax expands and contracts about 12 to 15% as heat is added to or removed from the wax which is held at its melting point temperature.
Various means for controlling the expandable medium temperature may be employed and are well known in the art. Depending on the application, various means may be employed to control the speed with which the expandable medium expands or contracts. The speed of expansion and contraction would control the speed of the operation of the piston or the actuation rod.
The high output force actuators usually comprise an output rod that would move from about halfan inch to about 1.5 inches, with a traveling force of up to 150 pounds. Another type of high force linear actuator would be a threaded rod, using steel balls in the thread groove, to transmit motion and force from a mating threaded nut. The nut is rotated by a high ratio gearbox driven by a motor. The threaded rod is restrained from rotating with the nut, so it translates linearly, exerting linear force and consequent linear motion on an external load. Other mechanical, pneumatic, hydraulic and thermal actuators are utilized. An aspect of the present invention is the mounting mechanism that allows the movement of the actuator body relative to the moving element or piston. Previously known mounting mechanisms fix the body of the actuator to the applicable structure, such as a satellite. The only moving element relative to the structure is the piston or force output rod. The mounting mechanism of the present invention provides for movement of the actuator body relative to the structure.
The HOP actuator 11 is attached to plate 12 , which serves to retain the HOP in its position and transmit the reaction force to slide 16 . Further, in accordance with the embodiment shown in the FIGURE, the plate transmits the spring compression motion to microswitch 19 .
The HOP is attached to the slide 16 through various means, including a snap ring 13 or other methods. Other methods include attaching the HOP to the slide with screw threads, welded assembly, adhesive bonding, drill and pin and the like. The cap 14 is employed to retain and preload spring 15 against the slide flange 161 . The cap also guides the linear motion of one end of the slide. The cap may be attached to the body of the mount with various means, including these mentioned above for the attachment of the HOP to the plate.
The spring 15 provides a reference preload force that the actuator acts against. Various springs or other compliant members may be utilized in the present invention. For example, coil springs or Belleville washer springs may be utilized. In a preferred embodiment of the present invention, the tension of the spring may be adjusted, dependent on the application.
The slide 16 transmits the HOP reaction force to the spring. Additionally, the slide transmits the spring compression motion to the plate.
The guide housing 18 guides the linear motion of one end of the slide 16 and transmits spring force from cap to other end of spring. The bracket 20 supports the microswitch 19 in accordance with a preferred embodiment of the present invention. The microswitch senses the motion of the plate 12 and controls power to the HOP 11 heaters. A linear position sensor with an output proportional to position and therefore (due to the linear spring) force, can also be used for accurate proportional force control. This force is optionally remotely commanded. Other sensors which can be utilized include optical motion sensors or magnetic motion sensors, or the like. In a preferred embodiment, movement of the plate in response to the movement of the slide would break the power supply to any heaters employed in the HOP actuator.
The invention has been described with respect to certain preferred embodiments. Various changes and modifications to the embodiments herein, chosen for purposes of illustration, will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention as claimed herein, they are intended to be included within the scope thereof. | A mechanical actuator assembly is disclosed. The actuator assembly comprises an actuator body with an element moveable with respect to said body to perform a function. In general, the moveable element is in the form of a piston or a rod. The actuator assembly further comprises a mounting mechanism allowing the movement of the actuator body relative to the moving element or piston in response to preset conditions of pressure or force. | 5 |
FIELD OF THE INVENTION
[0001] The present invention concerns a solid state memory, for example being organized in targets, each target containing one or more logical units (LUN), each logical unit containing one or more blocks and each block containing one or more pages. Such a device is e.g. a NAND flash memory device, which is designed according to the Open NAND Flash Interface Specification (ONFI).
BACKGROUND OF THE INVENTION
[0002] Such devices are known from US patent publication US2008/0183949, which describes a method for programming a flash memory. Programming within this context is understood by a person skilled in the art as writing or storing bits in the flash memory cells. Programming data on a flash memory is done by programming data of one page at one time. If not enough data is provided at the end of the data stream to program a full page, the page programmed at the end of the data stream is only partially filled. If the data stream to be programmed continues later on, there is a partially filled page between other fully filled pages. This can be regarded as insufficient. A better solution is provided by reading out again the partially filled data page and completing the data with data later provided to be written and then programming a full data page to the flash memory. Partially filled pages are reduced at the cost of additional read and programming cycles.
[0003] US patent publication US2006/0136656 describes a block as the minimum erasable unit of a flash memory. It further describes the problem of partially filled pages which cannot be erased easily because the minimum erasable unit is not a page but a block. Thus, the flash memory is worn down unnecessarily.
[0004] The effect of partially filled pages also arises when a switching operation between two logical units is performed. When a switch from a first logical unit to a second logical unit is performed, the data left in an input buffer is programmed to the first logical unit and after that the switching to the second logical unit is made. If later on data are programmed to the first logical unit, a new page is used for programming the data and thus, partially used pages arise in the logical unit.
[0005] According to the Open NAND Flash Interface Specification (ONFI), writing data to a NAND Flash device is done by issuing a PROGRAM PAGE command with the corresponding logical unit number (LUN), block address and page address to the target. Afterwards data of a complete memory page, usually multiple kilobytes, is written to the page register of the selected logical unit. When a full page is written to the page register, the logical unit starts to program the data to its memory array. During programming, the logical unit is busy and the next page can be written to the logical units' page register after programming of the first page is finished. After a complete page has been written to the page register and the page program has been started, the other logical units of the target could be selected and used. The ONFI specification provides also a possibility to program partial pages, but that would implicate additional programming times and the reachable bandwidth would decrease.
[0006] The following programming instructions are defined according to the ONFI specification:
PAGE PROGRAM: Data is written to the data register and programming starts after the data phase has finished. PAGE CACHE PROGRAM: Data is written to the data register and after the data phase is finished, the content of the data register is copied to the cache register and programming starts. PAGE PROGRAM INTERLEAVED: Data is written to multiple data registers of one LUN and programming starts when the last data register is filled.
[0010] The known page program flow is used to write a complete data page to the page register of the NAND device and to start the programming to the memory array. Each procedure causes a number of state switches of the target state machine and the logical unit state machine. The state switches of the state machines in dependence of the procedure are shown below:
[0000]
Procedure
Target State Sequence
LUN State Sequence
Write Command 80h
T_Idle
L_Idle
to NAND device
-> T_Cmd_Decode
-> T_PP_Execute
-> T_PP_AddrWait
Write LUN-, block-
T_PP_AddrWait
L_Idle
and page-address
-> T_PP_Addr
->
to NAND device
-> T_PP_LUN_Execute
L_Idle_TargetRequest
-> T_PP_LUN_DataWait
-> L_ PP Execute
-> L_PP_Addr
-> L_PP_WaitForData
Write complete
T_PP_LUN_DataWait
data page to NAND
-> T_PP_LUN_ DataPass
L_PP_WaitForData
device
-> T_PP_LUN DataWait
-> L_PP_AcceptData
-> L_PP_WaitForData
Write Command 10h
T_PP_LUN_DataWait
to NAND device
-> T_PP_Cmd_Pass
L_PP_WaitForData
-> T_Idle
-> L_PP_Prog
-> L_PP_ProgWait
-> L_PP_Sts
-> L_Idle
[0011] Interleaved operations enable to issue multiple commands of the same type to different blocks of the same logical unit. The known interleaved page program flow is used to write complete data pages to multiple independent page registers of a logical unit and to start the programming to the memory array when all registers are filled.
[0000]
Procedure
Target State Sequence
LUN State Sequence
Write Command
T_Idle
L_Idle
80h to NAND
-> T_Cmd_Decode
device
-> T_PP_Execute
-> T_PP_AddrWait
Write LUN-, block-
T_PP_AddrWait
L_Idle
and page-address
-> T_PP_Addr
-> L_Idle_TargetRequest
to NAND device
-> T_PP_LUN_Execute
-> L_PP_Execute
-> T_PP_LUN_DataWait
-> L_PP_Addr
-> L_PP_WaitForData
Write complete
T_PP_LUN_DataWait
L_PP_WaitForData
data page to
-> T_PP_LUN_DataPass
-> L_PP_AcceptData
NAND device
-> T_PP_LUN_DataWait
-> L_PP_WaitForData
Write Command
T_PP_LUN_DataWait
L_PP_WaitForData
11h to NAND
-> T_PP_Cmd_Pass
-> L_PP_Ilv
device
-> T_PP_IlvWait
-> L_PP_Ilv_Wait
Write Command
T_PP_IlvWait
L_PP_Ilv_Wait
80h* to NAND
-> T_PP_AddrWait
device
Write LUN-, block-
T_PP_AddrWait
L_PP_Ilv_Wait
and page-address
-> T_PP_Addr
-> L_PP_Addr
to NAND device
-> T_PP_LUN_Execute
-> L_PP_WaitForData
-> T_PP_LUN_DataWait
Write complete
T_PP_LUN_DataWait
L_PP_WaitForData
data page to NAND
-> T_PP_LUN_DataPass
-> L_PP_AcceptData
device
-> T_PP_LUN_DataWait
-> L_PP_WaitForData
Write Command
T_PP_LUN_DataWait
L_PP_WaitForData
10h to NAND
-> T_PP_Cmd_Pass
-> L_PP_Prog
device
-> T_Idle
-> L_PP_ProgWait
-> L_PP_Sts
-> L_Idle
*The address cycles for the program operation of state ‘T_PP_IlvWait’ is intended to have a different interleaved block address than the one issued in the preceding program operation.
[0012] If data of two independent sources are recorded in independent LUNs of a target, one of the above described processes is first issued to the first LUN for the first independent source and after finishing the writing process, one of the above described processes is issued to the second LUN for writing the data of the second independent source to the second LUN.
[0013] When independent concurrent streams should be recorded to a flash device, it is advantageous to write the different streams to different logical units. The file management is easier with such a regular strategy and the full bandwidth of a logical unit is guaranteed for recording of an incoming data stream. If data of the streams arrive in blocks of smaller size than the page size, there is a need to cache data of each stream in a cache arranged outside of the flash device and to write it to the NAND Flash device, when a full page for one logical unit is ready to be programmed. Depending on the amount of streams and logical units, a lot of cache memory is needed outside the memory device, while the available page register inside the device remains unused.
SUMMARY OF THE INVENTION
[0014] It is an object of the invention to provide a solid state memory and a method for operating a solid state memory which reduces the problem of partially filled pages. It is a further object of the invention to provide a solid state memory and a method for operating a solid state memory which reduces the need for outside cache memory and which makes use of the internal page registers in case multiple incoming data streams are programmed to a flash device.
[0015] In order to use the page register of a logical unit as input buffer for the corresponding incoming data stream, an active logical unit has to be switched to dependent on the nature of the currently incoming stream, even if the pages on the other logical units can not yet be completely filled. The ONFI specification does not address this problem and does not provide a dedicated mechanism.
[0016] According to the invention, a solid state memory for storing at least one incoming data stream has multiple logical units within one target. Each logical unit has at least one page for programming data to the memory. The solid state memory contains an internal buffer memory, often called page register, for temporarily storing the incoming data stream before the incoming data are programmed to at least one page. Further, the internal buffer memory keeps data, which are not yet programmed, when a switching operation between different logical units is performed. This has the advantage that in the event of switching from a first logical unit to a second logical unit the remaining data, which is not yet enough to completely fill a page, does not need to be programmed but is kept in the page register. If later on, more data for this logical unit is provided, this data is added to the remaining data and the remaining data and the new data are programmed together as a full page. This enhances the overall bitrate for programming a specific logical unit because programming only partial pages is omitted. As programming of a full page and of a partial page needs almost the same time, less programming cycles are necessary for programming a specific amount of data in case care is taken to program only full pages in any possible case. Further, the problem of pages in the solid state memory device that are only partially filled with data in the solid state memory device is omitted. The solid state memory is more efficiently used.
[0017] Advantageously, the solid state memory is organized as groups of targets, wherein each target contains at least one logical unit. Each logical unit is provided with a page register for temporarily storing the incoming data to be programmed to this logical unit. Further, each logical unit contains at least one block. Erasing the memory is done blockwise. Each block contains at least one page. Data stored to be in one page is programmed at one time.
[0018] Preferably, each logical unit of the solid state memory has an internal buffer for temporarily storing the incoming data stream before the data is programmed to the pages. The size of the internal buffer is at least the size of one page plus the size of data received during the programming cycle of a page at highest allowable input bitrate. Thus:
[0000] Size internalBuffer ≧Size Page +Time PageProgramCycle *Bitrate InputData
[0019] This has the advantage that during programming of a page also the data for programming the next page can be received in the internal buffer. An internal buffer of the size of for example two pages can receive data for a whole page to be programmed during the programming cycle of another page, if the bitrate of the input data is high enough. Thus, the overall waiting times are reduced and the bitrate of the solid state memory is further enhanced.
[0020] Advantageously, the storage device is a NAND Flash device, which is operated according to the Open NAND Flash Interface (ONFI) specification. The ONFI specification does not foresee a specific algorithm to omit partially programmed pages if switching between different logical units is performed and to reduce programming times and thus programming bitrate in case of partial page programming. The proposed memory device has the advantage that it is essentially in accordance with the ONFI specification and omits partial pages at the same time. A device according to the invention deviates only from the known implementation of the ONFI standard. The program instructions of the ONFI standard are still used. The deviation from the implementation rules as known in the art is not in contradiction to the ONFI standard. Thus, a device according to the invention can still be regarded as being in compliance with the ONFI standard. Further, programming times are reduced because complete pages are programmed whenever appropriate. Besides that, the invention concerns a solid state storage device, which operates in a page oriented way and which is applicable for example for streaming applications, especially for streaming of several video sources in parallel, as central storage device for capturing measurement data of a research environment, especially for capturing of several measurement data streams in parallel or similar environments.
[0021] Preferably, the solid state memory is part of a video capturing camera system with one or more cameras. The data issued by the cameras are provided to the solid state memory device. Advantageously, the solid state memory stores data streams captured by different cameras in different logical units. Preferably, the camera system is provided for 3D video capturing. In this case several video streams, at least one of which is of high data rate are generated. That video data streams have to be stored in real time in parallel. The solid state memory provides several advantages for a camera system as described above. Storing the data streams of different cameras in different logical units has the advantage that an easy file structure is provided and the data are organized in accordance with the hierarchical memory structure. Thus, especially using a camera system with more than one camera, as it is for example mandatory for 3D capture, multiple data streams have to be stored at the same time. In addition, the data stream output by a camera has usually a high data rate. Using high definition cameras (HD), the data stream of one camera is for example up to 2 Gbits/s. The solid state storage according to the invention is especially advantageous for such systems, because the input data rate of the storage device is not unnecessarily reduced by writing and reading partially filled pages. A benefit is high in systems with multiple cameras, wherein data streams of different cameras are stored in different logical units, because switching between different logical units is done regularly in such systems and the problem of pages that are not written in one cycle or that are only partially written would arise frequently. Besides 3D capture, also multidimensional capture is in the focus of the film industry. The invention is also dedicated to scene captures of a multidimensional environment in real time.
[0022] Preferably, a method is implemented for operating a solid state storage device comprising at least one logical unit. Each logical unit comprises at least one page and a page being programmed at one time. In the method according to the invention, at least one incoming data stream is sequentially input into the solid state memory. The data is temporarily stored in an internal buffer, the page register. The internal buffer is for example a buffer as described above and allocated to a logical unit. A checking step is performed whether the internal buffer contains an amount of data that is sufficient for one complete page to be programmed. If the internal buffer contains sufficient data for one complete page to be programmed, at least one complete page is programmed. Sufficient data for one complete page may be just slightly more data than necessary for one complete page, but it may also be data that is sufficient to fill several complete pages. If a switching operation is performed between different logical units, not yet programmed data of the internal buffer of the logical unit that is currently active is kept in the internal buffer. The switching between the logical units is then performed. This has the advantage that before switching from a first logical unit to a second logical unit the remaining data which does not fill a complete page does not need to be programmed but is kept in the internal buffer and is still kept after switching is finished. If, later on, more data for this logical unit is provided, this data is added to the remaining data and the remaining data and the new data are programmed together as a full page. This reduces the overall programming time because programming of a partial page needs approximately the same processing time as programming a full page. Thus, by programming only full pages, the programming bandwidth is enhanced. Further, the problem of pages which are only partially filled with data during one programming cycle in the solid state memory device is omitted. The solid state memory is more efficiently used.
[0023] Advantageously, the method is used for storing the input data streams which are captured by different cameras in different logical units. Storing the data streams of different cameras in different logical units has the advantage that an easy file structure is provided and the data are organized in accordance with the hierarchical memory structure. Thus, especially using a camera system with more than one camera, as it is for example mandatory for 3D capture, multiple data streams have to be stored at the same time. In addition, the data stream output by a camera has usually a high data rate. Using high definition cameras (HD), the data stream of one camera is for example up to 2 Gbits/s. The provided solid state storage is especially advantageous for such systems, because the input data rate of the storage is not unnecessarily reduced by reading and writing partial pages. The benefit is high in systems with multiple cameras, wherein data streams of different cameras are stored in different logical units, because switching between different logical units is done regularly in such system and the problem of partial pages would arise often. Besides 3D capture, also multidimensional capture is in the focus of the film industry. The invention is also dedicated to scene captures of a multidimensional environment.
[0024] Preferably, the method operates according to the Open NAND Flash Interface (ONFI) specification. Advantageously, after data for one logical unit was received in a data register and in case a switch of the logical'unit is to be performed, the target is set into state T_PP_Ilv_Wait using the Page Program Interleaved command 11 h . Using this command, the logical unit is set into state L_PP_Ilv_Wait. Subsequently, the target is kept in state T_PP_Ilv_Wait and the logical unit is kept in state L_PP_Ilv_Wait until the data register of a LUN is filled with a full page. Then, these data are programmed to a page using the commands 10 h or 15 h . Setting the target into state T_PP_LUN_DataWait and setting logical units into state L_PP_WaitForData after programming a full page to a logical unit using the commands 10 h or 15 h to prevent the target from deleting the data from the page register of the addressed logical unit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] For better understanding the invention shall now be explained in more detail in the following description with reference to the figures. It is understood that the invention is not limited to these exemplary embodiments and that specified features can also expediently be combined and/or modified without departing from the scope of the present invention.
[0026] FIG. 1 depicts the hierarchical structure of a solid state memory device
[0027] FIG. 2 depicts a method for operating a solid state memory device according to the invention
[0028] FIG. 3 depicts a state diagram of a target according to the invention
[0029] FIG. 4 depicts a state diagram of a logical unit according to the invention
[0030] FIG. 5 depicts a state diagram of a solid state memory comprising one target and two logical units according to the invention
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0031] FIG. 1 depicts a structure of a NAND flash memory, which is operated by the ONFI specification command set according to the invention. The NAND flash memory is organized as a target. A target contains one or multiple logical units LOGICAL UNIT 0 , LOGICAL UNIT 1 , . . . , LOGICAL UNIT L, each logical unit LOGICAL UNIT 0 , LOGICAL UNIT 1 , . . . , LOGICAL UNIT L contains multiple blocks BLOCK 0 , BLOCK 1 , . . . , BLOCK M and a block BLOCK 0 , BLOCK 1 , . . . , BLOCK M contains multiple pages PAGE 0 , PAGE 1 , . . . , PAGE N. A page PAGE 0 , PAGE 1 , . . . , PAGE N is typically a read or write unit. This means that a page contains the smallest number of data that can be read or written in one step. A block BLOCK 0 , BLOCK 1 , . . . , BLOCK M is typically an erase unit. This means that a block contains the smallest number of data that can be erased in one step. A logical unit LOGICAL UNIT 0 , LOGICAL UNIT 1 , . . . , LOGICAL UNIT L is an operating unit that operates independently. Each logical unit LOGICAL UNIT 0 , LOGICAL UNIT 1 , . . . , LOGICAL UNIT L contains a page register PAGE REGISTER for temporarily storing data to be written or to be read. Further, each logical unit contains a controller unit CU_LU_ 0 , CU_LU_ 1 , . . . , CU_LU_L for operating the logical unit LOGICAL UNIT 0 , LOGICAL UNIT 1 , . . . , LOGICAL UNIT L. A target TARGET further contains a target control unit CU_TRG for controlling the device on a target level.
[0032] FIG. 2 depicts a program flow of a device according to the invention. In step S 1 it is checked if incoming data is available.
[0033] If incoming data is available (YES), a page program command 80 h is written to the target in step S 2 . In step S 3 the LUN-, block-, page- and column address is written to the page register of the NAND flash target. In step S 4 , the next data word is written to the NAND flash target. Then, it is checked if a complete page is available in the page register of the flash target in step S 5 .
[0034] If a complete page is available (YES), in step S 8 the data is stored in the respective page of the target using the page program 10 h or page cache program 15 h command. In step S 9 , the page- and block-addresses are incremented. Then, a further page program command 80 h is written to the target in step S 10 . In step S 11 the LUN-, block-, page- and column address is written to the page register of the NAND flash target.
[0035] Step 6 is performed if no complete page is available in step S 5 (NO). Step 6 is also performed after step S 11 . In step 6 it is checked if there are remaining bytes available. If there are remaining bytes available (YES), the method proceeds with step S 4 . If there are no remaining bytes available (NO), an interleaved command 11 h is written to the NAND in step 7 target and the method proceeds with step S 1 .
[0036] If no incoming data is available in step S 1 (NO), it is checked if the end of the record is reached in step S 12 . If the end of the record is not reached (NO), the method further proceeds with step S 1 . If the end of the record is reached (YES), the method checks in step S 13 if there are unfinished pages left in the register.
[0037] If there are unfinished pages in the register (YES), a page program 80 h command is written to the NAND target in step S 14 and the LUN-, block-, page- and column address is written to the NAND flash device in step S 15 . Then, the method further proceeds with step S 8 .
[0038] If no unfinished pages are left in the register in step S 13 (NO), the method proceeds with storing the data in the respective page of the target using the page program 10 h or page cache program 15 h command in step S 16 . Then, the method restarts with step S 1 .
[0039] It is to be noted that storing data on a page in a logical unit using a page program command or a cache page program command requires two cycles. In the first cycle, both, page program and cache page program, are initiated using the 80 h command. In the second cycle, the 10 h command is issued for page program and the 15 h command is issued for cache page program.
[0040] FIG. 3 depicts a target state diagram according to the invention. The target state diagram according to the invention considered separately corresponds to the target state diagram according to the ONFI standard. The initial state is T_Idle. After a command is received, the target decodes the received command in state T_Cmd_Decode. If the decoded command is a page program 80 h command, the target switches to state T_PP_Execute. Then, the target sets tLastCmd to 80 h . If R/B# is cleared to zero, then tbStatus 78 hReq is set to TRUE. In addition, all LUNs are requested to clear their page registers. Then, in state T_PP_AddrWait, the target waits for an address cycle. After an address cycle is received, the address cycle received is stored in state T_PP_Addr. If a further address cycle is required, the target switches to back to T_PP_AddrWait to receive the next address cycle. If no further address cycle is required, the target switches to state T_PP_LUN_Execute. The LUN indicated by the row address received is selected and the target issues the program to the LUN. Then the target waits for the data word or command cycle to be received from the host in state T_PP_LUN_DataWait and passes the data word to the selected LUN in state T_PP_LUN_DataPass. When a command is received in T_PP_LUN_DataWait, the target switches to state T_PP_Cmd_Pass. Then, the command is passed to the respective LUN. If the command is an 11 h command, the target switches to state T_PP_IlvWait to wait for the next command to be issued. If this command is a page program 80 h , the next byte is written to the LUN according to the above described method. On the other hand, if the command is a 10 h or 15 h command, the target returns back to the initial state T_Idle.
[0041] FIG. 4 depicts a logical unit state diagram according to the invention. The logical unit state diagram according to the invention considered separately corresponds to the logical unit state diagram according to the ONFI standard. The initial state is L_Idle. After a target request is received for this LUN, the LUN switches to state L_Idle_TargetRequest and waits for the command issued by the target. If the target indicates a program request, the LUN switches to L_PP_Execute and then to L_PP_Addr to record the address received by the target. Further, the correct page register is selected based on the interleaved address and the column in the page register is selected according to the column address received. Then, the LUN receives the data passed by the target in the states L_PP_WaitForData and L_PP_AcceptData. In case the LUN then receives an 11 h command, the LUN switches to state L_PP_IlvWait until the target requests a further program command for this LUN. In case the LUN receives a 10 h or 15 h command in state L_PP_WaitForData, the LUN switches to states L_PP_Prog, L_PP_ProgWait and L_PP_Sts and programs the respective data to the respective pages.
[0042] To illustrate the inventive method in more detail, FIG. 5 depicts a state diagram of a solid state memory comprising one target and two logical units according to the invention. Thus, the allowable combinations of target states and corresponding logical units LU 1 , LU 2 are shown. It is understood, that the inventive method is also applicable for at least one target containing more than two logical units. Fore sake of simplicity, only states are illustrated in which page program commands or page cache program commands of the first cycle 80 h or the second cycle 10 h / 15 h or interleaved commands 11 h are issued. It is understood that in order to switch from a first state to a second one of the target and of the respective LUN, the state switches according to FIG. 3 and FIG. 4 between the first and second state have also to be performed. The state switches are performed as described in the ONFI specification.
[0043] In the initial state S 50 , the target is in idle state T_Idle. The LUNs are as well in the idle states L_Idle. If a page program command of the first cycle 80 h is received for LU 1 , state S 51 is activated. Thus, the target is switched to T_PP_LUN_DataWait and LU 1 is switched to L_PP_WaitForData. LU 2 has not changed its state. Accordingly, LU 1 is now ready for receipt of data. After data receipt in LU 1 , it is checked if a page program 10 h or page cache program 15 h of the second cycle is issued. In this case, the data is programmed to a page of the first logical unit LU 1 and the state machine switches back to idle state S 50 . If an interleaved command 11 h for LU 1 is issued, the target switches to T_PP_IlvWait and LU 1 switches to L_PP_Ilv_Wait. LU 2 stays in L_idle state. This corresponds to S 52 of FIG. 5 . Thus, further page program commands 80 h of the first cycle can be issued either for logical unit LU 1 or LU 2 . In case a page program command 80 h is issued for LU 1 , the state machine switches back to state S 51 . In case a page program command 80 h is issued for LU 2 , the state machine switches to S 53 . To issue a page program 80 h command of the first cycle to a second logical unit, while an interleaved 11 h command was issued to a first logical unit before, forms part of the inventive character of the method. The state transition is thus indicated by a bold arrow. The target is then waiting for new data or a new command from the host in state T_PP_LUN_DataWait, LU 1 is waiting in state L_PP_IlvWait and LU 2 is waiting for data to be received in state L_PP_WaitForData. As a consequence, LU 1 is not reset to idle state before LU 2 is switched to a state in which it waits for data. Thus, when switching to LU 2 from LU 1 according to the inventive method, data in the page registers from LU 1 are not lost, which is one of the advantages of the inventive method.
[0044] State S 53 is reached after a command of the first cycle was issued to LU 2 , thus in state S 53 a page program command 10 h , a page cache program command 15 h or an interleaved command 11 h of the second cycle dedicated to LU 2 are allowable. Issuing a page program command 10 h or page cache program command 15 h dedicated to LU 2 leads to T_Idle state of the target and L_Idle state of LU 2 . This corresponds to state S 54 if FIG. 5 . From state S 54 a page program 80 h or page cache program 80 h command of the first cycle can be issued for LU 1 or LU 2 . In case the 80 h command is issued to LU 1 , the state machines switches to state S 51 . In case the 80 h command is issued to LU 2 , the state machine switches to S 53 .
[0045] If an interleaved 11 h command is issued to LU 2 in state S 53 , the target switches to T_PP_IlvWait and LU 2 switches to L_PP_IlvWait. As LU 1 stays in L_PP_IlvWait, the state machine is in state S 59 and is ready to receive the next request of the first cycle either for LU 1 or LU 2 . In case the 80 h command is issued to LU 1 , the state machine switches to state S 57 for waiting for a command for LU 1 . Switching from state S 59 , which was reached after receiving an interleaved command for LU 2 , to state S 57 , in which the state machine waits for a page program command 10 h , a page cache program command 15 h or an interleaved command 11 h of the second cycle dedicated to LU 1 is part of the invention. The known way would be to receive a page program command 80 h of the first cycle for LU 1 in state S 59 , if state S 59 was reached by an interleaved command 11 h for LU 2 . The state machine would then switch back to state S 53 for waiting for a command for LU 2 as already described above.
[0046] States S 55 , S 56 , S 57 and S 58 and their state switches correspond to states S 51 , S 52 , S 53 and S 54 and their state switches, if the commands are issued correspondingly for the other logical unit. A detailed description is therefore omitted.
[0047] Thus, the program flow according to the invention uses the interleaved page program 11 h to bring target and LUN to a state waiting for additional data T_PP_IlvWait and L_PP_IlvWait, respectively. This is the case in states S 52 , S 56 and S 59 according to FIG. 5 . According to the invention, writing small data blocks of less than one page size to the page register of a fist logical unit, switching to another logical unit and continue writing to the page register of the fist logical unit after a switch back to the first logical unit was made, and then programming a complete page to the first logical unit is enabled.
[0048] The program flow to write data, e.g. of different data sources to different LUNs is as follows.
[0000]
Procedure
Target State
LUN State
Write Command
T_Idle
L_Idle
80h to NAND
-> T_Cmd_Decode
device
-> T_PP_Execute
-> T_PP_AddrWait
Write LUN-, block-
T_PP_AddrWait
L_Idle
and page-address
-> T_PP_Addr
-> L_Idle_TargetRequest
to NAND device
-> T_PP_LUN_Execute
-> L_PP_Execute
-> T_PP_LUN_DataWait
-> L_PP_Addr
-> L_PP_WaitForData
Write data block
T_PP_LUN_DataWait
L_PP_WaitForData
of less than
-> T_PP_LUN_DataPass
-> L_PP_AcceptData
pagesize to NAND
-> T_PP_LUN_DataWait
->L_PP_WaitForData
device
Write Command
T_PP_LUN_DataWait
L_PP_WaitForData
11h to NAND
-> T_PP_Cmd_Pass
-> L_PP_Ilv
device
-> T_PP_IlvWait
-> L_PP_Ilv_Wait
[ . . . write data to other logical units . . . ]
Write Command
T_PP_IlvWait
L_PP_Ilv_Wait
80h* to NAND
-> T_PP_AddrWait
device
Write LUN-, block-,
T_PP_AddrWait
L_PP_Ilv_Wait
page- and
-> T_PP_Addr
-> L_PP_Addr
column-address to
-> T_PP_LUN_Execute
-> L_PP_WaitForData
NAND device
-> T_PP_LUN_DataWait
Write additional
T_PP_LUN_DataWait
L_PP_WaitForData
data to NAND
-> T_PP_LUN_DataPass
-> L_PP_AcceptData
device, until full
-> T_PP_LUN_DataWait
-> L_PP_WaitForData
page has been
written
Write Command
T_PP_LUN_DataWait
L_PP_WaitForData
10h to NAND
-> T_PP_Cmd_Pass
-> L_PP_Prog
device
-> T_Idle
-> L_PP_ProgWait
-> L_PP_Sts
-> L_Idle
* The address cycles for the page program operation of state T_PP_IlvWait have the same interleaved block address as the one issued in the preceding page program operation, but the column address is incremented to place the further data blocks to the right position in page register. | The invention concerns a solid state memory, comprising multiple logical units. The solid state memory contains an internal buffer for temporarily storing the incoming data steam before the incoming data are programmed to at least one page. The internal buffer keeps data that are not yet programmed in case a switch from one logical unit to another is performed. A method for operating such a device is presented. | 6 |
CROSS REFERENCE(S) TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. Section 119 of Korean Patent Application Serial No. 10-2013-0143850, entitled “Carrier For Manufacturing Printed Circuit Board And Manufacturing Method Thereof, And Method For Manufacturing Printed Circuit Board” filed on Nov. 25, 2013, which is hereby incorporated by reference in its entirety into this application.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to a printed circuit board, and more particularly, to a carrier for manufacturing a printed circuit board.
[0004] 2. Description of the Related Art
[0005] Generally, a printed circuit board (PCB) is a component in which a copper foil is wired on one surface or both surfaces of the board made of various synthetic resins, an IC or electronic components are mounted on the board, and an electrical wiring between the electronic components is implemented. Recently, with the trend of electronic devices toward high performance and miniaturization, a multilayer printed circuit board has been produced as a board for mounting electronic components at a high density.
[0006] The multilayer printed circuit board is formed by using as a core layer a reinforcing material in which a glass fiber, and the like is impregnated in a resin composition and alternately stacking an insulating layer and a wiring layer on both surfaces of the core layer by a build up process. Since the wiring layer is finely formed, the multilayer printed circuit board may be mounted with electronic components at a high density.
[0007] However, since it is difficult to implement fineness of a through hole penetrating through the core layer, a coreless substrate which does not have the core layer is drawing attention recently.
[0008] In the case of the coreless substrate, since the core layer is not used, the use of a carrier member serving as a support during the manufacturing process is required. That is, the substrate may be finally completed by repeatedly stacking the insulating layer and the wiring layer on both surfaces of the carrier and then separating a laminate from the carrier.
[0009] Even though various types of carrier members are present, the carrier member generally has a structure in which a first metal plate and a second metal plate are stacked on the insulating layer, having a release layer disposed therebetween. The substrate is formed by using the carrier member as the support and then the carrier is separated from the substrate by the release layer.
[0010] However, since the carrier member has a structure in which the release layer is exposed to the outside, the exposed release layer may crack due to an externally physical impact, permeation of medicines, and the like during the manufacturing process of the substrate.
[0011] As the method for solving the problem, Japanese Patent Laid-Open Publication No. 2013-162124 discloses a structure in which an outside of the carrier is enclosed with a protective means of a resin composition. However, in this case, the manufacturing process may be ineffective due to the addition of separate components and costs may be increased. Further, the protective means is made of the resin composition, and thus is expected to be vulnerable to substrate warpage characteristics.
SUMMARY OF THE INVENTION
[0012] An object of the present invention is to protect a release layer from the outside by using a carrier having a structure in which a release layer is buried in a surface of an insulating layer and increase reliability of a product.
[0013] According to an exemplary embodiment of the present invention, there is provided a carrier for manufacturing a printed circuit board, including: an insulating layer; a release layer buried in at least any one of top and bottom surfaces of the insulating layer and having a length shorter than that of the insulating layer; and a metal foil bonded to a surface of the insulating layer in which the release layer is buried and having a length longer than that of the release layer.
[0014] The release layer may be buried, having margin parts from both side ends of the insulating layer.
[0015] A length of the metal foil may be equal to that of the insulating layer.
[0016] The release layer may be made of a metal material.
[0017] The release layer may be made of metal of a material different from the metal foil.
[0018] A thickness of the release layer may be changed depending on a weight of a wiring layer which is stacked over the insulating layer.
[0019] The release layer may be configured of a first release layer which is buried in the insulating layer and a second release layer which is buried in the other surface of the first release layer, and a weight of the wiring layer which is stacked on one surface of the insulating layer including the first release layer and a weight of the wiring layer which is stacked on the other surface of the insulating layer including the second release layer may be symmetrical to each other.
[0020] According to another exemplary embodiment of the present invention, there is provided a manufacturing method of a carrier for manufacturing a printed circuit board, including: preparing an insulating layer; burying a release layer having a length shorter than that of the insulating layer in at least any one of top and bottom surfaces of the insulating layer; and bonding a metal foil having a length longer than that of the release layer to a surface of the insulating layer in which the release layer is buried.
[0021] In the burying of the release layer, the burying layer may be buried, having margin parts from both side ends of the insulating layer.
[0022] In the bonding of the metal foil in the surface of the insulating layer in which the release layer is buried, the metal foil may be bonded so that the release layer and the metal foil are vacuum compressed.
[0023] According to still another exemplary embodiment of the present invention, there is provided a method for manufacturing a printed circuit board using the carrier for manufacturing a printed circuit board as described above, including: forming a substrate on the carrier for manufacturing a printed circuit board on which the metal foil is formed; cutting an edge of the carrier for manufacturing a printed circuit board including the substrate in a thickness direction so that the release layer is exposed; and separating the substrate from the carrier for manufacturing a printed circuit board.
[0024] In the cutting of the edge of the carrier for manufacturing a printed circuit board in a thickness direction, the edge may be cut along an edge line of the release layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a cross-sectional view of a carrier for manufacturing a printed circuit board according to an exemplary embodiment of the present invention.
[0026] FIGS. 2 to 4 are process diagrams sequentially illustrating a manufacturing method of a carrier for manufacturing a printed circuit board according to the exemplary embodiment of the present invention.
[0027] FIGS. 5 to 7 are process diagrams sequentially illustrating a method of manufacturing a printed circuit board using the carrier for manufacturing a printed circuit board according to the exemplary embodiment of the present invention.
[0028] FIG. 8 is a diagram for describing another exemplary embodiment of FIG. 6 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Various advantages and features of the present invention and methods accomplishing thereof will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. However, the present invention may be modified in many different forms and it should not be limited to exemplary embodiments set forth herein. These exemplary embodiments may be provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0030] In addition, terms used in the present specification are for explaining the embodiments rather than limiting the present invention. Unless explicitly described to the contrary, a singular form includes a plural form in the present specification. The word “comprise” and variations such as “comprises” or “comprising,” will be understood to imply the inclusion of stated constituents, steps, operations and/or elements but not the exclusion of any other constituents, steps, operations and/or elements.
[0031] Hereinafter, a configuration and an acting effect of exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings.
[0032] FIG. 1 is a cross-sectional view of a carrier for manufacturing a printed circuit board according to an exemplary embodiment of the present invention. Additionally, components shown in the accompanying drawings are not necessarily shown to scale. For example, sizes of some components shown in the accompanying drawings may be exaggerated as compared with other components in order to assist in the understanding of the exemplary embodiments of the present invention. Meanwhile, throughout the accompanying drawings, the same reference numerals will be used to describe the same components. For simplification and clearness of illustration, a general configuration scheme will be shown in the accompanying drawings, and a detailed description of the feature and the technology well known in the art will be omitted in order to prevent a discussion of exemplary embodiments of the present invention from being unnecessarily obscure.
[0033] Referring to FIG. 1 , a carrier 100 for manufacturing a printed circuit board according to an exemplary embodiment of the present invention has an insulating layer 110 , a release layer 120 , and a metal foil 130 as basic components.
[0034] A resin material of the insulating layer 110 may be appropriately selected in consideration of insulating property, heat resistance, moisture resistance, and the like. For example, as an optimal polymer material forming the insulating layer 110 , an epoxy resin, a phenol resin, a urethane resin, a silicon resin, a polyimide resin, and the like may be used and to increase a mechanical strength of a support, a prepreg in which reinforcing materials, such as a glass fiber and an inorganic filler, are impregnated may also be used.
[0035] The release layer 120 may be provided in the state buried in the surface of the insulating layer 110 . That is, when the release layer 120 is a rectangular flat plate which has an upper surface, a lower surface opposite thereto, and a side having a predetermined thickness, the release layer 120 is buried in a form in which the upper surface is exposed to the outside and the lower surface and the side are enclosed with a resin. The term ‘burying’ indicates one buried in the above form.
[0036] The release layer 120 may be buried in any one of the upper and lower surfaces of the insulating layer 110 or may be buried in both surfaces thereof. However, the present invention illustrates, as the example, the case in which the release layers 120 are buried in both surfaces of the insulating layer 110 to manufacture the coreless substrate.
[0037] Herein, the length of the release layer 120 may be smaller than that of the insulating layer 110 . Therefore, the release layers 120 may be buried, having predetermined margin parts M from both side ends of the insulating layer 110 .
[0038] Since the margin part M is a region discarded after a cutting process in the method for manufacturing a printed circuit board using the carrier 100 , an interval of the margin part M may be set to be smaller to extend a real area of the substrate. However, when the margin part M is set to be too small, a bonded portion with the metal foil 130 is reduced to make the structure instable. Therefore, the interval of the margin part M may be set to have an appropriate length in consideration of the relationship therebetween.
[0039] The metal foil 130 may be provided while being bonded with the surface of the insulating layer 110 in which the release layer 120 is buried. Therefore, according to the exemplary embodiment of the present invention in which the release layers 120 are buried in both surfaces of the insulating layer 110 , the metal foils 130 may be provided on both surfaces of the insulating layer 110 as illustrated in FIG. 1 .
[0040] The metal foil 130 may be used as a wiring layer of the substrate separated from the carrier 100 . Therefore, as a construction material of the metal foil 130 , copper (Cu), nickel (Ni), aluminum (Al), or the like may be used, but the exemplary embodiment of the present invention is not limited thereto.
[0041] A length of the metal foil 130 may be formed to be larger than that of the release layer 120 , such that the metal foil 130 is bonded to the insulating layer 110 made of an adhesive resin composition in the margin part M region. Therefore, to extend the bonded area to the insulating layer 110 , the length of the metal foil 130 may be formed to be equal to that of the insulating layer 110 .
[0042] Generally, in the carrier for manufacturing a printed circuit board, the release layer is made of adhesive materials such as a polymer material, for example, fluorines, silicons, polyethylene terephthalates, polymethyl pentene, and the like so as to being bonded to metal. However, according to the exemplary embodiment of the present invention, the release layer 120 is made of a metal material. For example, the release layer 120 may be made of a metal selected from gold (Au), silver (Ag), iron (Fe), titanium (Ti), tin (Sn), nickel (Ni), and molybdenum (Mo). However, to prevent the chemical bonding by the same kind of materials, the metal materials different from the metal foil 130 may be used.
[0043] As such, as the release layer 120 is made of the metal materials, the release layer 120 is not bonded to the metal foil 130 , and then even though the substrate is separated from the carrier 100 in a method for manufacturing a printed circuit board using the carrier 100 according to the exemplary embodiment of the present invention, separate foreign materials do not remain on the surface of the metal foil 130 which becomes the wiring layer of the substrate.
[0044] Meanwhile, a thickness of the release layer 120 may be changed depending on a weight of the wiring layers which are stacked on the insulating layer 110 in the method for manufacturing a printed circuit board using the carrier 100 according to the exemplary embodiment of the present invention.
[0045] Generally, at the time of manufacturing the substrate, when heat is applied during a reflow process, the insulating layer 110 made of a high expansive resin is expanded and contracted, such that warpage occurs. A substrate is further warped to a heavier side when an interlayer metal occupancy factor by the wiring layer, that is, a weight is asymmetrical. Therefore, according to the exemplary embodiment of the present invention, for example, when the weight of the wiring layer disposed on the upper portion among the multilayer wiring layers which are stacked on the insulating layer 110 is larger than the wiring layer disposed on the lower portion, the thickness of the release layer 120 is larger and thus the metal weight of the lower portion is increased, such that the warpage of the substrate may be induced to the lower portion.
[0046] Meanwhile, when a total weight of the wiring layer which is stacked on the insulating layer 110 based on the insulating layer 110 is different from that of the wiring layer which is stacked on the lower portion of the insulating layer 110 , the wiring layer is further expanded to a side at which the total weight of the wiring layer is larger. Therefore, in this case, the metal weight of the upper and lower portions of the insulating layer 110 may be symmetrical with each other by controlling the thickness of the release layer 120 which is buried in one surface of the insulating layer 110 and the thickness of the release layer 120 which is buried in the other surface thereof.
[0047] For example, in the case in which the total weight of the wiring layer on the upper portion of the insulating layer 110 based on the insulating layer 110 is larger than that of the wiring layer on the lower portion of the insulating layer 110 , when the release layer 120 buried in the upper portion of the insulating layer 110 is called a first release layer and the release layer 120 buried in the lower surface of the insulating layer 110 is called a second release layer, the thickness of the second release layer may be larger than that of the first release layer. As a result, the total weight of the wiring layer on the upper portion of the insulating layer 110 including the first release layer and the total weight of the wiring layer on the lower portion of the insulating layer 110 including the second release layer are symmetrical to each other, such that the substrate warpage phenomenon may be improved.
[0048] As such, when the release layer 120 is made of a metal material, foreign matters do not remain on the surface of the metal foil 130 after the substrate is separated, such that process defects may be reduced and the substrate warpage phenomenon may be improved.
[0049] Hereinafter, a method for manufacturing the carrier 100 for manufacturing a printed circuit board according to the exemplary embodiment of the present invention will be described.
[0050] FIGS. 2 to 4 are process diagrams sequentially illustrating a manufacturing method of a carrier 100 for manufacturing a printed circuit board according to the exemplary embodiment of the present invention. First, as illustrated in FIG. 2 , the insulating layer 110 is prepared.
[0051] As the insulating layer 110 , a thermosetting resin such as epoxy resin and a thermoplastic resin such as polyimide may be used. Further, to increase a mechanical strength of the support, a prepreg in which reinforcing materials, such as a glass fiber and an inorganic filler, are impregnated in a polymer resin may also be used. Herein, to bury the release layer 120 in the surface of the insulating layer 110 , it is important to prepare the insulating layer 110 in a semi-hardening state.
[0052] Next, as illustrated in FIG. 3 , burying the releasing layer 120 in at least any one of the upper and lower surfaces of the insulating layer 110 is performed.
[0053] A metal thin plate may be used as the release layer 120 . In this case, an outside of the prepared metal thin plate is removed by mechanical polishing or chemical polishing to be manufactured in a form having a shorter length than the insulating layer 110 . For example, the mechanical polishing may be performed by using any one of belt sander, grinder, and a sand blaster and the chemical polishing may be performed by using an etchant, but the exemplary embodiment of the present invention is not limited thereto.
[0054] By doing so, when the release layer 120 is manufactured, the release layer 120 is provisionally bonded to the surface of the insulating layer 110 , having the predetermined margin parts M from both side ends of the insulating layer 110 , and then a force is applied in a stacking direction to bury the release layer 120 in the surface of the insulating layer 110 .
[0055] Next, as illustrated in FIG. 4 , a process of bonding the metal foil 130 to the surface of the insulating layer 110 in which the release layer 120 is buried proceeds.
[0056] The length of the metal foil 130 is larger than that of the release layer 120 (equal to the length of the insulating layer 110 in a more preferable form) and since the insulating layer 110 has adhesion in a semi-hardening state, the metal foil 130 is bonded to the insulating layer 110 in the margin part M region. Further, as the release layer 120 is made of a metal material, the metal foil 130 and the release layer 120 are compressed in a vacuum state without being bonded to each other.
[0057] Hereinafter, a method of manufacturing a printed circuit board by using the carrier 100 for manufacturing a printed circuit board which is completed according to the exemplary embodiment of the present invention will be described.
[0058] FIGS. 5 to 7 are process diagrams sequentially illustrating the method for manufacturing a printed circuit board using the carrier 100 for manufacturing a printed circuit board according to the exemplary embodiment of the present invention. First, as illustrated in FIG. 5 , a process of forming the substrate 200 on the prepared carrier 100 for manufacturing a printed circuit board proceeds.
[0059] In more detail, in the carrier 100 , the substrate 200 may be stacked on a surface on which the metal foil 130 is formed. Since the exemplary embodiment of the present invention discloses the carrier 100 in which the metal foils 130 are disposed on both surfaces of the insulating layer 110 , FIGS. 5 to 7 illustrate that the substrates 200 are on both of the upper and lower surfaces of the carrier 100 .
[0060] The substrate 200 is formed by a build up process of repeatedly stacking a build up insulating layer 210 and a wiring layer 220 . The substrate 200 may be formed by performing a putter operation, pattern formation, hole machining, a plating process, an etching process, and the like, in particular, the wiring layer 220 may be formed by a general semi-additive process (SAP), modified semi-additive process (MSAP), subtractive method, and the like which are known to those skilled in the art. The method of forming the substrate 200 is already known to those skilled in the art, and therefore the detailed description thereof will be omitted.
[0061] Next, as illustrated in FIG. 6 , a process of cutting an edge of the carrier 100 for manufacturing a printed circuit board including the substrate 200 in a thickness direction proceeds.
[0062] This may proceed by a routing process. In this case, the edge of the carrier 100 is cut along a cutting line A illustrated in FIG. 6 so that the release layer 120 is exposed. However, when the edge of the carrier 100 is cut along a cutting line A, a part of the release layer 120 is cut, which leads to the reduction in the area of the substrate. As illustrated in FIG. 8 , it may be preferable to cut the edge of the carrier 100 along a cutting line B so as to coincide with an edge line of the release layer 120 .
[0063] As such, when the edge of the carrier 100 is cut along the cutting line A or the cutting line B, as illustrated in FIG. 7 , the margin part M which is the bonded portion between the metal foil 130 and the insulating layer 110 is separated and the substrate 200 may be separated from the carrier 100 while supplying air between the release layer 120 and the metal foil 130 which are vacuum compressed.
[0064] As described above, in the case of using the carrier 100 for manufacturing a printed circuit board according to the exemplary embodiment of the present invention, the release layer 120 is buried in the surface of the insulating layer 110 and provided in a form sealed with the metal foil 130 , and thus may protect the release layer 120 from the externally physical impact or the permeation of medicines until the above-mentioned process of manufacturing the substrate is completed.
[0065] In the case of using the carrier for manufacturing a printed circuit board according to the exemplary embodiments of the present invention, the release layer is buried on the surface of the insulating layer and is provided in a form sealed with the metal foil, thereby protecting the release layer from the externally physical impact or the permeation of medicines until the manufacturing process of the substrate is completed.
[0066] Further, even though the substrate is separated from the carrier, it is possible to prevent the separate foreign matters from remaining on the surface of the metal foil which is the wiring layer of the substrate.
[0067] In addition, it is possible to improve the substrate warpage phenomenon by controlling the thickness of the release layer depending on the weight of the wiring layer stacked over the carrier.
[0068] The present invention has been described in connection with what is presently considered to be practical exemplary embodiments. Although the exemplary embodiments of the present invention have been described, the present invention may be also used in various other combinations, modifications and environments. In other words, the present invention may be changed or modified within the range of concept of the invention disclosed in the specification, the range equivalent to the disclosure and/or the range of the technology or knowledge in the field to which the present invention pertains. The exemplary embodiments described above have been provided to explain the best state in carrying out the present invention. Therefore, they may be carried out in other states known to the field to which the present invention pertains in using other inventions such as the present invention and also be modified in various forms required in specific application fields and usages of the invention. Therefore, it is to be understood that the invention is not limited to the disclosed embodiments. It is to be understood that other embodiments are also included within the spirit and scope of the appended claims. | Disclosed herein is a carrier for manufacturing a printed circuit board, including: an insulating layer; a release layer buried in at least any one of top and bottom surfaces of the insulating layer and having a length shorter than that of the insulating layer; and a metal foil bonded to a surface of the insulating layer in which the release layer is buried and having a length longer than that of the release layer, thereby increasing reliability of a product in the manufacturing the substrate using the carrier. | 8 |
SUMMARY OF THE INVENTION
This invention relates to new (carbamoylthioacetyl) cephalosporin derivatives of the formula ##EQU3##
R represents hydrogen, lower alkyl, phenyl-lower alkyl, tri(lower alkyl)stannyl, tri(lower alkyl)silyl, a salt forming ion or the group ##EQU4## R 1 represents hydrogen, lower alkyl, phenyl, thienyl or furyl; R 2 represents lower alkyl, lower alkoxymethyl, phenyl or phenyl-lower alkyl; R 3 represents hydrogen, hydroxy or lower alkanoyloxy; and R 4 represents lower alkyl, phenyl or phenyl-lower alkyl.
The preferred members within each group are as follows: R is hydrogen, alkali metal, trimethylsilyl, benzhydryl, or ##EQU5## especially hydrogen, pivaloyloxymethyl, sodium or potassium; R 1 is hydrogen, lower alkyl or phenyl, especially hydrogen or phenyl; R 2 is lower alkyl, especially methyl or ethyl, or lower alkoxymethyl, especially methoxymethyl; R 3 is preferably hydrogen or acetoxy; and R 4 is methyl or t-butyl.
DETAILED DESCRIPTION OF THE INVENTION
The various groups represented by the symbols have the meanings defined below and these definitions are retained throughout this specification.
The lower alkyl groups are the straight and branched chain hydrocarbon groups in the series from methyl to heptyl, the C 1 to C 4 members and especially methyl and ethyl being preferred.
The lower alkanoyloxy groups represented by R 3 include the acyl radicals of lower fatty acids containing alkyl radicals of the type described above, e.g., acetoxy, propionoxy, butyryloxy, etc., acetoxy being preferred.
The phenyl-lower alkyl radicals include a phenyl ring attached to a lower alkyl group of the kind described above as well as those containing two phenyl groups such as benzhydryl.
The salt forming ions represented by R are metal ions, e.g., alkali metal ions such as sodium or potassium, alkaline earth metal ions such as calcium or magnesium, or an amine salt ion, e.g., a (lower alkyl)amine like methylamine or triethylamine, etc.
The new (carbamoylthioacetyl)cephalosporin derivatives of this invention are produced by reacting a 7-aminocephalosporanic acid compound [which includes 7-aminocephalosporanic acid (7-ACA), 7-amino-3-desacetoxycephalosporanic acid (7-ADCA) and other derivatives] of the formula ##EQU6## with a carbamoylacetic acid of the formula ##EQU7## or an activated derivative of the former (II).
The activated derivatives referred to include, for example, the reaction product with an anhydride forming reagent such as ethylchloroformate, benzoyl chloride, pivaloyl chloride, etc., or an activated ester like the benzhydryl ester, t-butyl ester, trimethylsilyl ester or trimethylstannyl ester or triethylamine salt. Dicyclohexylcarbodiimide can also be used to effect the reaction.
One preferred synthesis comprises reacting the acid of formula III with the benzhydryl ester of 7-ACA or 7-ADCA and then hydrolyzing the ester with trifluoroacetic acid and anisole to obtain the free carboxyl group in the 4-position.
Another preferred synthesis comprises forming the 2,5-dioxo-1-pyrrolidinyl ester by reacting the acid of formula III with N-hydroxysuccinimide in the presence of dicyclohexylcarbodiimide, reacting the product with the benzhydryl ester of 7-ACA or 7-ADCA and hydrolyzing the product of that reaction with trifluoroacetic acid and anisole.
The reaction between the 7-aminocephalosporanic acid compound and the carbamoylacetic acid can be carried out, for example, by dissolving or suspending the acid in an inert organic solvent such as chloroform, tetrahydrofuran, methylene chloride, dioxane, benzene or the like, and adding, at a reduced temperature of about 0°-5°C, about an equimolar amount of the 7-ACA or 7-ADCA compound in the presence of an activating compound such as dicyclohexylcarbodiimide. The product of the reaction is then isolated by conventional procedures, e.g., by concentration or evaporation of the solvent. If a derivativve of the 7-aminocephalosporanic acid compound, such as the benzhydryl ester is used, the free acid is obtained by hydrolysis, e.g., with trifluoroacetic acid or the like. Salts can then be derived from the free acid.
When R is the acyloxymethyl group ##EQU8## this group can be introduced into the 7-aminocephalosporanic acid moiety prior to the reaction with the carbamoylthioacetic acid or the activated derivative by treatment with one to two moles of a halomethyl ester of the formula (IV)
hal--CH.sub.2 OCOR.sub.4
wherein hal is halogen, preferably chlorine or bromine, in an inert organic solvent such as dimethylformamide, acetone, dioxane, benzene or the like, at about ambient temperature or below.
The carbamoylacetic acid of formula III is produced by reacting a mercaptoacetic acid of the formula ##EQU9## with a base, e.g., an alkylamine like triethylamine, and with an isocyanate R 2 N=C=O, in an inert solvent like tetrahydrofuran, then acidifying, e.g., with hydrochloric acid or the like.
Alternatively the acid of formula V is converted to an ester like the benzhydryl ester by reaction with a diazomethane like diphenyldiazomethane, followed by reaction with the isocyanate and treatment with trifluoroacetic acid/anisole.
Further process details are also provided in the illustrative examples.
Certain of the compounds of this invention may exist in different optically active forms. The various stereoisomeric forms as well as the racemic mixtures are within the scope of the invention.
The compounds of this invention have a broad spectrum of antibacterial activity against both gram positive and gram negative organisms such as Staphylococcus aureus, Salmonella schottmuelleri, Pseudomonas aeruginosa, Proteus vulgaris, Escherichia coli and Streptococcus pyogenes. They are useful as antibacterial agents, e.g., to combat infections due to organisms such as those named above, and in general they can be utilized in a manner similar to cephradine and other cephalosporins. For example, a compound of formula I or a physiologically acceptable salt thereof can be used in various animal species affected by infections of such bacterial origin in an amount of about 1 to 75 mg/kg daily, orally or parenterally, in single or two to four divided doses.
Up to about 600 mg. of a compound of formula I or a physiologically acceptable salt thereof is administered by incorporating in an oral dosage form such as tablets, capsules or elixirs or in an injectable form in a sterile aqueous vehicle prepared according to conventional pharmaceutical practice.
The following examples are illustrative of the invention. All temperatures are in degrees celsius. Additional variations are produced in the same manner by appropriate substitution in the starting material.
EXAMPLE 1
DL-[(Methylcarbamoyl)thio]phenylacetic acid
10.08 g. (60 mM) of α-mercaptophenylacetic acid and 6.6 g. (60 mM) of triethylamine are dissolved in 50 ml. of tetrahydrofuran and 3.42 g. (60 mM) of methylisocyanate dissolved in 20 ml. of tetrahydrofuran are added dropwise with stirring. After stirring for 2 hours, the solvent is drawn off in a vacuum and the oily residue is dissolved in water. The mixture is then acidified with 2N hydrochloric acid and extracted three times each with 20 ml. of ether. After drying off the ether, 10.5 g. of white crystalline DL-[(methylcarbamoyl)thio]phenylacetic acid are obtained, which is recrystallized from ether/petroleum ether, m.p. 128°-129°.
EXAMPLE 2
DL-[(Ethylcarbamoyl)thio]phenylacetic acid
By substituting ethylisocyanate for the methylisocyanate in the procedure of Example 1, white crystalline DL-[(ethylcarbamoyl)thio]phenylacetic acid is obtained and recrystallized from cyclohexane, m.p. 115°-117° (dec.).
EXAMPLE 3
DL-α-[[[(Methoxymethyl)amino]carbonyl]thio]phenylacetic acid
By substituting methoxymethyl isocyanate for the methylisocyanate in the procedure of Example 1, white crystalline DL-α-[[[(methoxymethyl)amino]carbonyl]thio]phenylacetic acid is obtained and recrystallized from cyclohexane, m.p. 111°-112°.
EXAMPLE 4
DL-3-[(Acetyloxy)methyl]-7β-[[[[(methylamino)carbonyl]thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-carboxylic acid, diphenylmethyl ester
1 g. (5 mM) of dicyclohexylcarbodiimide is added to 1.1 g. (5 mM) of DL-[(methylcarbamoyl)thio]phenyl acetic acid in 50 ml. of tetrahydrofuran and stirred for 1 hour at -5°. 2.1 g. (5 mM) of 7-aminocephalosporanic acid, benzhydryl ester in 15 ml. of tetrahydrofuran are then added and the mixture is stirred for 5 hours at 0° and for 1 hour at room temperature. The precipitate of dicyclohexylurea is filtered off and the filtrate is evaporated. The oily residue is dissolved in 20 ml. of methylene chloride. Filtration over charcoal and precipitation with petroleum ether produces 1.3 g. of white DL-3-[(acetyloxy)methyl-7β-[[[[(methylamino)-carbonyl]thio]phenyl]acetyl]amino]-8-oxo-5-thia-1-azabicyclo-[4.2.0]oct-2-ene-carboxylic acid, diphenylmethyl ester which is reprecipitated from methylene chloride/carbon tetrachloride, m.p. 73° (dec.).
EXAMPLE 5
DL-3-[(Acetyloxy)methyl]-7β-[[[[(methylamino)carbonyl]thio]-phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-carboxylic acid
3 g. of the product of Example 4 are dissolved at 0° in 25 ml. of trifluoroacetic acid/anisole and stirred for 15 minutes. After drawing off the trifluoroacetic acid in vacuum, an oily residue remains which is washed repeatedly with absolute ether until it becomes quite firm. The residue is dissolved in sodium bicarbonate solution, filtered and acidified with hydrochloric acid, with cooling, to a pH of 2.5. The solution is extracted three times each with 20 ml. of ethyl acetate. The organic phase is dried and evaporated. 0.9 g. of DL-3-[(Acetyloxy)methyl]-7β-[[[[(methylamino)carbonyl]thio]phenylacetyl]-amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-carboxylic acid is obtained as a light yellow powder m.p. 121° (dec.) after reprecipitation from methylene chloride/petroleum ether.
EXAMPLE 6
DL-3-[(Acetyloxy)methyl]-7β-[[[[(methylamino)carbonyl]thio]-phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, potassium salt dihydrate
By freeze drying a molecular equivalent aqueous solution of the product of Example 5 in potassium bicarbonate, DL-3-[(acetyloxy)methyl]-7β-[[[[(methylamino)carbonyl]thio]-phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, potassium salt dihydrate is obtained as a beige powder, m.p. 152°.
EXAMPLE 7
Alternate method for producing the product of Example 5
4.5 g. (20 mM) of DL-[(methylcarbamoyl)thio]phenylacetic acid are dissolved in 50 ml. of tetrahydrofuran. 2 g. (20 mM) of triethylamine are added and while stirring at a temperature of 0° 2.5 g. (20 mM) of ethyl chloroformate are added dropwise. After one hour, a solution of 5.4 g. (20 mM) of 7-aminocephalosporanic acid, triethylamine salt in 200 ml. of methylene chloride are added and the whole mixture is stirred for 14 hours at 5°. After filtering and drawing off the solvent, the oily residue is treated with water. The aqueous solution is extracted with ethyl acetate, filtered and acidified to pH 2.5. Repeated extraction with ethyl acetate and evaporation of the ethyl acetate solution in vacuum yields after recrystallization from methylene chloride/petroleum ether, DL-3-[(acetyloxy)methyl]-7β-[[[[(methylamino)-carbonyl]thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-carboxylic acid as a light yellow powder, 2.5 g., m.p. 61°. The product produced by this method is only 67% pure.
EXAMPLE 8
3-[(Acetyloxy)methyl]-7β-[[[[[(methoxymethyl)amino]carbonyl]-thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
The procedure of Example 4 is followed using 4.2 g. (10 mM) 7-ACA-benzhydryyl ester, 2.5 g. (10 mM) of DL-α-[[[(methoxymethyl)amino]carbonylthio]phenylacetic] acid and 2.06 g. (10 mM) of dicyclohexylcarbodiimide in 50 ml. of tetrahydrofuran. After reprecipitation from methylene chloride/petroleum ether, 3.8 g. of 3-[(acetyloxy)methyl]-7β-[[[[[(methoxymethyl)amino]carbonyl]thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester are obtained as a cream-colored powder, m.p. 93°.
EXAMPLE 9
DL-3-[(Acetyloxy)methyl]-7β-[[[[[(methoxymethyl)amino]carbonyl]-thio]phenyacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
After treating the ester of Example 8 with trifluoracetic acid/anisole DL-3-[(acetyloxy)methyl]-7β-[[[[[(methoxymethyl)-amino]carbonyl]thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid is obtained in the form of a beige powder, m.p. 121° after reprecipitation from methylene chloride/carbon tetrachloride.
EXAMPLE 10
DL-3-[(Acetyloxy)methyl]-7β-[[[[[(methoxymethyl)amino]carbonyl]-thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, potassium salt
By the freeze drying a molecular equivalent solution of the product of Example 9 in aqueous potassium bicarbonate, DL-3-[(acetyloxy)methyl]-7β-[[[[[(methoxymethyl)amino]carbonyl]-thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, potassium salt is obtained as a beige powder, m.p. 146°.
EXAMPLE 11
DL-3-[(Acetyloxy)methyl]-7β-[[[[(ethylamino)carbonyl]thio]-phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester
4.8 g. (20 mM) of DL-[(ethylcarbamoyl)thio]phenylacetic acid are dissolved in 150 ml. of tetrahydrofuran and stirred with 8.4 g. (20 mM) of 7-ACA benzhydryl ester and 4.05 g. (20 mM) of dicyclohexylcarbodiimide for 8 hours at 0°. By evaporating the filtered solution, 9 g. of DL-3-[(acetyloxy)methyl]-7β-[[[[(ethylamino)carbonyl]thio]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, diphenylmethyl ester are obtained as a yellow powder, m.p. 75° (dec.).
EXAMPLE 12
α-[[(Methylamino)carbonyl]thio]phenylacetic acid, 2,5-dioxo-1-pyrrolidinyl ester
4.5 g. (20 mM) of DL-[(methylcarbamoyl)thio]phenylacetic acid are stirred with 2.3 g. (20 mM) of N-hydroxysuccinimide and 4.05 g. (20 mM) of dicyclohexylcarbodiimide in 150 ml. of tetrahydrofuran at 0° for 18 hours. Evaporation of the filtered solution and recrystallization from benzene yields 5.6 g. of α-[[(methylamino)carbonyl]thio]phenylacetic acid, 2,5-dioxo-1-pyrrolidinyl ester as light yellow crystals, m.p. 153°-156°.
The following additional products having the formula (c) in the table are obtained by the procedure of Example 4 by substituting for the 7-aminocephalosporanic acid benzhydryl ester, the starting material (a), and for the [(methylcarbamoyl)thio]phenylacetic acid, the starting material (b) with the substituents indicated in the table:
TABLE__________________________________________________________________________ S ∠ R.sub.1 --CH--CO--NH----CH--CHCH.sub.2 R.sub.1 --CH--COOH |||| | S--C--NH--R.sub.2 ∥C----NC--CH.sub.2 --R.sub.3 S--C--NH--R.sub.2 ∥ OO∠ ∥ C O | C--OR ∥ O(a) (b) (c)ExampleR R.sub.1 R.sub.2 R.sub.3__________________________________________________________________________13 --CH.sub.3 H --CH.sub.3 H14 --C.sub.2 H.sub.5 --CH.sub.3 --C.sub.2 H.sub.5 --OH15 --C.sub.3 H.sub.7 --C.sub.2 H.sub.5 --OCOCH.sub.3O∥16 --CH.sub.2 OC--CH(CH.sub.3).sub.2 --CH.sub.2 OCH.sub.3 --CH.sub.3 --OCOCH.sub.3O∥17 --CH.sub.2 OC--C.sub.6 H.sub.5 C.sub.6 H.sub.5 --CH.sub.3 --OCOCH.sub.318 C.sub.6 H.sub.5 -- --C.sub.2 H.sub.5 H19 H --C.sub.2 H.sub.5 --OCOCH.sub.320 --Sn(CH.sub.3).sub.3 --CH.sub.3 --OH21 --CH.sub.3 --OCOCH.sub.322 Si(CH.sub.3).sub.3 C.sub.6 H.sub.5 n-butyl --OH23 H C.sub.6 H.sub.5 C.sub.3 H.sub.7 --OCOCH.sub.324 Na --C.sub.2 H.sub.5 H25 K --CH.sub.3 --OCOCH.sub.326 H H --C.sub.2 H.sub.5 --OCOCH.sub.327 H --CH.sub.2 OC.sub.2 H.sub.5 --OCOCH.sub.328 H C.sub.6 H.sub.5 -- --CH.sub.2 OCH.sub.3 H29 H C.sub.6 H.sub.5 -- C.sub. 6 H.sub.5 -- --OCOCH.sub.330 H C.sub.6 H.sub.5 -- H31 H H C.sub.6 H.sub.5 --OCOCH.sub.332 H H --OCOCH.sub.3__________________________________________________________________________ | (Carbamoylthioacetyl)cephalosporin derivatives of the general formula ##EQU1## wherein R is hydrogen, lower alkyl, phenyl-lower alkyl, tri(lower alkyl)stannyl, tri(lower alkyl)silyl, a salt forming ion or the group ##EQU2## R 1 is hydrogen, lower alkyl, phenyl, thienyl or furyl; R 2 is lower alkyl, lower alkoxymethyl, phenyl or phenyl-lower alkyl; R 3 is hydrogen, hydroxy or lower alkanoyloxy; and R 4 is lower alkyl, phenyl or phenyl-lower alkyl; are useful as antibacterial agents. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to switching power supplies and in particular to a switching power supply with a current mode control loop.
2. Prior Art
Current mode controlled switching power supplies are well known. In a current mode controlled switching power supply, the output voltage from the power supply is measured and compared to a reference voltage. Any error signal resulting from a difference between the two voltages is then used to control the peak switch current from the power switch on a cycle-by-cycle basis. It is known that in a normal current mode controlled switching power supply a capacitor cannot be used to couple the input of the power transformer to the power switches because such a capacitor results in an instability which causes the power supply to latch up. The use of such a coupling capacitor is desirable to prevent transformer saturation due to DC currents through the transformer.
FIG. 1 illustrates a dual loop current mode switching power supply of the prior art and FIG. 2a illustrates a half bridge converter circuit wherein two capacitors replace two switching transistors normally present in a full bridge of a type known in the prior art. In the circuit of FIG. 1, the output voltage on lead 22 from the power supply (often called a "converter") is sent to error amplifier 25 on the inverting input lead 27a of amplifier 25. Voltage reference 28 is applied to the noninverting input lead 27b of error amplifier 25. The output signal from amplifier 25 comprises an error voltage which represents the difference between the voltage on output lead 22 and reference voltage 28. This error voltage controls the current source loop 30 which in turn controls the peak switch current from power switch 23 on a cycle-by-cycle basis. The second loop 30 includes a comparator 26 which senses the difference between the error voltage from error amplifier 25 and a signal produced by current sense circuit 27 proportional to the peak switch current from power switch 23 on a cycle-by-cycle basis. When the power switch 23 is configured as a push-pull circuit, loop 30 corrects for transformer imbalances caused by, for example, differences between storage times of switch transistors (such as transistors Q1 and Q2 in FIG. 2a), noise and load transients which can cause transformer flux saturation and thus excessive DC current in the switching transistors.
Different forms of dual loop current mode control have been utilized for their advantages of speed, performance and reliability. Unfortunately, none of these are usable with "half bridge" converter topologies, or with other push-pull topologies that are capacitor coupled to the output transformer. This is because the introduction of one or more capacitors to the circuit results in an instability which causes the system to latch up in a failure mode. FIG. 2a illustrates a typical capacitor coupled topology employing a half bridge. In FIG. 2a switching transistors Q1 and Q2 are driven by a control circuit and comprise part of power switch 23 shown in FIG. 1.
In the circuit of FIG. 2a when switch SW1 comprising transistor Q1 is on, current flows from the +V input lead through transistor Q1 and through the primary to node A. This current then charges capacitor C2 and discharges capacitor C1. When transistor Q1 shuts off and transistor Q2 comprising switch SW2 turns on, current I 1 flows in the opposite direction and discharges capacitor C2 and charges capacitor C1. During the flow of the current I 1 through the primary PRI in one direction or the other, current sense circuit 27 detects the magnitude of this current. Simultaneously with the current flow through the primary PRI, a current is generated in the secondary winding SEC of transformer T1. This secondary current is passed through a rectifier and a choke corresponding to choke 24 as shown in FIG. 1 and then stored on an output capacitor corresponding to C29 in FIG. 1.
One problem with the circuit of FIG. 2a is that while the voltage at node A theoretically should average precisely halfway between +V and -V, in reality the voltage on node A can easily deviate slightly from this ideal. The circuit then forces the voltage on node A either to approximately +V or -V depending upon the direction of the initial unbalance in this voltage. Typically, this takes between 3 and 20 cycles.
Transistors Q1 and Q2 each turn off only when the corresponding current I 1 or I 2 through the primary PRI reaches a maximum value as determined by the error voltage from amplifier 25. The length of time for this current to reach this maximum value depends upon the charge on C1 when Q1 turns on and the charge on C2 when Q2 turns on. The result is that the current I 1 flows for a much longer duration when V1 is much less than V2, as shown in FIG. 3, than the current I 2 in the other direction. Therefore the charges on capacitors C1 and C2 will continue to diverge in magnitude and ultimately most of the voltage across the half bridge circuit will be taken across capacitor C2 for the current imbalance shown in FIG. 3.
In any current mode control loop such as shown in FIG. 1, the switches in power switch 23 (corresponding to transistors Q1 and Q2 in FIG. 2a) are turned off at a control current that is the same for the positive and negative current flows I 1 and I 2 through the primary of transformer T1. Thus maximum current I 1 and maximum current I 2 as shown in FIG. 3 are the same and are set by the error voltage from error amplifier 25 (FIG. 1). If V1 and V2 are equal (i.e., the voltages across capacitor C1 and capacitor C2 are equal) the slopes S1 and S2 of the current pulses shown in FIG. 3 as illustrated will be equal because the slopes are approximately proportional to the voltages V1 and V2 across capacitors C1 and C2. These voltages control the rate of current rise in the output filter (corresponding to output choke 24 in FIG. 1) and the output transformer (corresponding to transformer T1 shown in FIG. 2a). This is not a stable situation as discussed above and is similar to a pencil balanced on its point. Just as any slight noise will cause the pencil to fall if there is a slight difference between V1 and V2 (for example if V2 is slightly greater than V1) the difference will increase until V2 is almost double its original value and V1 is almost zero. This occurs because a higher voltage across C2 causes a quicker rise (increase in the slope S2) of inductive current through the primary PRI of transformer T1 and a shortening of the on time of transistor W1. The opposite is true for the on-time of the current I 1 , through transistor Q1 with lower slope S1. Switch SW1 will eventually remain on until it is turned off other than by reaching its current limit.
Note that each transistor Q1 and Q2 is turned off when the current I 1 or I 2 equals Max I 1 or Max I 2 respectively. Max I 1 has the same absolute magnitude as Max I 2 . If the voltage V2 across capacitor C2 is approximately the same value as the voltage +V to -V across the half bridge converter, when transistor Q2 turns on, the current through transistor Q2 from capacitor C2 will reach Max I 2 in a very short time. Thus, the charge on capacitor C2 will not be substantially depleted before the signal from comparator 26 shuts off the transistor Q2. Transistor Q1 is then turned on. Unfortunately, the voltage V1 across capacitor C1 is very small. Therefore, the rate of rise of the current I 1 through transistor Q1 is very low and consequently a long time will elapse before this current reaches the maximum current at which the signal from comparator 26 will shut off transistor Q1. Indeed, if capacitor C2 is charged to voltage V2 and V2 equals the voltage across the half bridge circuit (+V to -V), the current I 1 will drop to zero rather than increase to Max I 1 . Thus, the half bridge converter will have "latched up" and will no longer switch unless a circuit is provided to switch Q1 automatically after the lapse of a given time. However, this still will not prevent the half bridge circuit from latching up with the voltage across one of the capacitors being grossly different from the voltage across the other capacitor.
In any event, within a few dozen switch cycles at most, the converter will latch up and provide very close to zero output current. It makes no difference if other control methods are used, such as fixed off time or hysteresis control of current level, for two examples. The above-described problem exists with any current turn off control that uses capacitive coupling such as capacitors C1 and C2 of FIG. 2a. Even a full bridge converter using current mode control will latch up if a capacitor is inserted in series with the primary of the output transformer. This precludes the utilization of a capacitor to prevent destructive currents under some transient or imbalance conditions in full bridge converters.
SUMMARY OF THE INVENTION
This invention overcomes the prior art latch up problem of a half bridge or full bridge capacitor coupled switching circuit (also called a "power stage") by adding a "balance circuit" to the converter. The balance circuit prevents the circuit from latching up initially upon turn on of the circuit or while the circuit is operating and indeed has enough capability to rebalance the circuit should the circuit initially start in a latched-up condition or otherwise latch up for any reason.
This invention will be more fully understood in conjunction with the following detailed description taken together with the following drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a current mode control switching power supply of the prior art;
FIG. 2a illustrates a known half bridge capacitor coupled power stage previously not capable of being used as part of the power switch 23 of the structure of FIG. 1 while FIG. 2b illustrates a full bridge capacitor coupled power stage known in the prior art but not previously usable with a current mode controlled power converter;
FIG. 3 illustrates the imbalance in the currents I 1 and I 2 through the primary "PRI" of transformer T1 which results in eventual latch up of the structure of FIG. 2a when this structure is used in a power switch such as power switch 23 of FIG. 1;
FIG. 4 illustrates the switching power supply circuitry incorporating the balance circuit of this invention to prevent latch up; and
FIGS. 5a through 5h comprise waveforms of use in explaining the operation of this invention.
DETAILED DESCRIPTION
The following detailed description illustrates one embodiment of this invention. This description is meant to be illustrative and not limiting and other embodiments of this invention will be obvious in view of this description to those skilled in the art.
In the structure of FIG. 4 the circuitry within the dashed lines 49 is, except for capacitors C9 and C10 and leads 55 and 56, conventional prior art circuitry and will be described briefly. The circuitry within the dashed lines 48 together with capacitors C9 and C10 and leads 55 and 56 comprises the balance circuitry of this invention which functions to prevent latch up of the power supply. The use of a half bridge circuit in a power supply in accordance with this invention is desirable because it allows transistors Q1 and Q2 to have lower voltage ratings than would otherwise be the case with a comparable push-pull circuit. Accordingly, the cost of the circuit can be significantly reduced although the current through each transistor is increased in proportion to the reduction of voltage. The balance circuit of this invention makes possible the use of a half bridge circuit with a current mode controlled power supply.
In the structure of FIG. 4, transistors Q1 and Q2 together with transformer T1 and capacitors C1 and C2 operate as described above in conjunction with FIG. 2a. Transistors Q1 and Q2 are switched on and off by switching transistors Q3 and Q4 which are part of and internal to the controller integrated circuit 44 for a switching mode power supply. The output current from the secondary of transformer T1 is rectified by diodes D1 and D2 and applied through a choke (which is shown as the primary of a coupling transformer T3) to charge capacitor C3. The DC output voltage from the power supply is taken from leads 50a, 50b across capacitor C3.
The positive voltage on capacitor C3 is transmitted by lead 51 through resistor R8 to the inverting input lead of operational amplifier 43. Connected to the noninverting input lead of operational amplifier 43 is a reference voltage shown in FIG. 4 as five (5) volts. Of course, this reference voltage could be any other appropriate voltage desired. A feedback circuit containing the series connected capacitor C5 and resistor R7 connects the output lead from operational amplifier 43 to the inverting input lead of amplifier 43 to provide high frequency compensation and gain roll off. The output signal from amplifier 43 is applied to noninverting input lead of comparator 42. Comparator 42 produces an output signal when the current through primary P of output transformer T1 (as represented by the value of the signal on the inverting input lead to comparator 42) reaches a value represented by the signal on the noninverting input lead to comparator 42. In accordance with this invention the signal on the inverting input lead to comparator 42 can have a first value when Q1 is on, and a second value when Q2 is on, wherein the first and second values are automatically generated by the balance circuit of this invention to correct any imbalance in the voltage across capacitor C1 when Q1 turns off and in the voltage across C2 when Q2 turns off.
When Q1 or Q2 turns on and current starts flowing in the primary of T1, the current in the secondary of transformer T2 is rectified via diodes D3 and D4. A voltage across resistor R10 is produced by this current that is proportional to the primary current in T1. This voltage is supplied to the inverting input lead to comparator 42 via resistor R11 and provides the inner current loop feedback signal (corresponding to the current within loop 30 in FIG. 1). Also, whenever Q1 and Q2 is on, there will be a voltage across primary P of T3 (the output choke). This voltage will normally have the same value for a turn off of either Q1 or Q2 if the voltage across C1 just before turn off of Q1 is equal to the voltage across C2 just before turn off to Q2 (this represents a balanced condition). Whenever the voltages on C1 and C2 become different at these two times (out of balance) the voltage across T3 primary will be one value while Q1 is on and another value Q2 is on. The voltage across the primary of T3 is coupled through to the secondary and inverted and applied to lead 52 (the inverting input lead) of comparator 42 through series-connected capacitor C6, resistor R6 and forward biased diode D6.
The voltage from the secondary of T3 is applied to series connected capacitor C6, resistor R6 and forward biased diode D6 to produce a related voltage on lead 52 connected to inverting input lead of comparator 42. This voltage on lead 52 determines the current which must flow through the primary P of T1 in order to produce a voltage on lead 58 which results in the voltage on lead 52 balancing to and equalling the voltage on the noninverting input lead of comparator 42. The result of this is effectively to shift the limits Max I 1 and Max I 2 as shown in FIG. 3 at which transistors Q1 and Q2 turn off so as to correct any imbalance in the voltages across capacitors C1 and C2 when their respective transistors Q1 and Q2 are ready to turn off.
The function of much of the circuitry in block 48 is simply to momentarily ground lead 57 connected to one terminal of capacitor C6 to restore the voltage of this point to zero during "storage time" of Q1 or Q2. Storage time is defined as that time after current comparator 42 has its output lead pulled low, but before either Q1 or Q2 has had enough time to turn off.
Comparator 42 comprises an LM339 comparator produced, for example, by National Semiconductor Corporation. This comparator has an open collector output lead which pulls down the voltage across capacitor C4 whenever the signal level on the inverting input lead to comparator 42 exceeds the signal level on the noninverting input lead to comparator 42. At this time, this voltage drop across capacitor C4 produces a signal to controller circuit 44 causing controller integrated circuit 44 to shut off either switching transistor Q3 or switching transistor Q4, whichever one was on. The time delay between the shutting off of Q3 and the shutting off of transistor Q1 controlled by Q3, or the shutting off of Q4 and the shutting off of transistor Q2 controller by Q4, is known as the storage time (see FIG. 5f) and represents the time required to sweep away charges stored on the base of Q1 or Q2 so that these devices will shut off. Typically, this time is two to three microseconds.
Control IC 44 in one embodiment as a TL 4 94 integrated circuit from Texas Instruments or Motorola, for example, the specifications of which are incorporated herein by reference. Other controllers can be used in place of a TL 494 if desired.
Driver 45 between controller IC 44 and transistors Q1 and Q2 is a common well known circuit, capable of a number of different configurations, which boosts the drive current from transistor Q3 to transistor Q1 and from transistor Q4 to transistor Q2. Driver 45 also isolates Q1 from Q2 and Q3, Q4 from Q1, Q2.
The turning off of whichever one of transistors Q3 and Q4 was on produces a positive going one microsecond pulse through one of the two 270 pF capacitors C9, C10 attached to Q3 or Q4. This pulse turns on Q5 in balance circuit 48 and bleeds off any excess charge from capacitor C6 through lead 57 and diode D8. Q5 is on only for about one microsecond or less and turns off before Q1 or Q2 turns off. When Q1 or Q2 turns off the voltage across T1 becomes zero and the voltage across T3 reverses polarity. This reversal causes C7 to force diodes D12 and D11 into conduction (zener diode D11 breaks down) and causes comparator 41 to pull down lines 52 (inverting input lead to comparator 42) and 53. This prevents a latch up problem during turn on of the supply and during off time of transistors Q1 and Q2 caused by R12 charging C6 and holding the output of comparator 42 in a low state. Note that when Q1 and Q2 are on, the output lead of comparator 41 open circuits allowing current to flow through resistor R12 to C6. However, the time constant of components R12 and C6 is sufficiently large to prevent C6 from being charged significantly during this on time.
When Q1 or Q2 next turn on, C7 is driven negative by the reversal of polarity on the secondary of T3 and charges C8 (the positively charged plate of C8 is grounded) through diode D13 and R3. The voltage across C8 is clamped at about 1.4 to 1.6 volts by diodes D9 and D10 which provide enough voltage to make up for the forward drops of diodes D7 and D8. Diodes D7 and D8 prevent forward biasing the collectors of transistors Q6 and Q5 respectively when the voltage on lead 57 goes above and below ground, respectively. Q6 serves a similar restoring function as Q5 but puts charge into C6 during storage time. Whenever transistor Q3 or Q4 in integrated circuit 44 is on, emitter current from Q3 or Q4 flows through the base to collector junction of Q7 into ground. This holds the emitter of Q7 at about zero volts and prevents current through R2 from turning on Q6. When both Q3 and Q4 are off and line 54 is negative and Q1 or Q2 is on (i.e., during storage time), current through R2 turns on Q6 and restores the charge on C6 to one diode drop (D7) below ground.
Diodes D5 and D6 protect comparator 42 from excessive excursions in input voltage on lead 52.
The reason for restoring the charge on C6 during storage time is that this will result in no net change in the current limit of the power supply as set by the maximum output signal (typically about 5.7 volts as set by resistor R14 (1K ohms) and diode D13 connected to a five volt reference as shown) for different output voltages (on leads 50a and 50b) or input voltages (on leads 51a and 51b).
The operation of this invention will be further explained taking into consideration FIGS. 5a through 5g. As shown in FIGS. 5a and 5b, transistors Q1 and Q2 are on periodically but alternately. Thus Q2 is off while Q1 is on, and vice versa. However the time between the turning off of Q1 and the turning on of Q2 is called the "off time". During this time the voltage on node A as shown in FIG. 5e is flat and constant. When Q1 is on, Q1 is turned off by the turning off of Q3. The time difference between the turning off of Q3 and the turning off of Q1 is called storage time. Storage time is shown in FIG. 5f. During the storage time Q3 (or Q4) is off and Q1 (or Q2) is preparing to shut off. When Q1 (or Q2) turns off, the off time before the turning on of Q2 (Q1) is controlled by the controller integrated circuit 44 by controlling a voltage on what is called the "dead time pin" (pin 4) of the integrated circuit. The higher the voltage from the dead time pin of the TL 494, the longer the off time.
One key to this invention is the recognition that the oscillations illustrated in FIG. 3 can be eliminated by reducing max I 1 and increasing max I 2 (in terms of absolute value) to reduce the time duration of the I 1 current pulses and to increase the time duration of the I 2 current pulses. This shift in the currents through the primary of T1 at which Q1 and Q2 shut off, restores balance to the voltages across capacitors C1 and C2. Note that when switch Q1 is on, the voltage across the secondary of transformer T1 is a measure of the voltage across capacitor C1 and when Q2 is on and Q1 is off, the voltage across the secondary of transformer T1 is a measure of the voltage across capacitor C2. Thus the secondary of choke T3 measures the voltage across C1 when switch Q1 is conducting and the voltage across C2 when switch Q2 is conducting. The voltage output from the secondary of T2 represents the current I 1 or I 2 , depending on whether Q1 or Q2 is on. However, the circuit of this invention feeds back negatively this voltage (note that the secondary winding of T3 is reversed compared to the primary of T3). Thus the voltage on lead 57, which represents approximately the voltage across C1 or C2, is negative, but rising as shown in FIG. 5c when Q1 or Q2 is on. At some time the voltage on lead 52 which represents an average of the voltages on leads 57 and 58 will rise and cause the output of comparator 42 to pull low. If the voltage across C1 is lower than the voltage across C2, then current I 1 normally will flow a relatively long time. The negative feedback will, however, reduce the time during which current I 1 flows by raising the initial voltage on line 57 (see FIG. 5c) when Q1 is turned on.
Comparator 42 is called an open collector comparator. As explained above, the open collector comparator has its output lead pulled low when the voltage on the inverting input lead goes higher than the voltage on the non-inverting input lead. The result is to turn off whichever one of transistors Q3 or Q4 was on and thus turn off either Q1 or Q2, respectively. Assuming that Q1 had been on, Q1 would now turn off and thereby cause the voltage on the inverting input lead to comparator 42 to drop low again. Thus the output lead of comparator 42 will open circuit, capacitor C4 will charge from current flowing from the oscillator of integrated circuit 44. At some voltage across capacitor C4, transistor Q4 in integrated circuit 44 will turn on, thereby turning on switching transistor Q2. At this time the voltage on the secondary of T1 will be a measure of the magnitude of the voltage across capacitor C2. The current through primary of T1 will be sensed by the current sense circuit including transformer T2. The output voltage on lead 58 will represent the current through the primary while transistor Q2 is on. Measures of the voltages on the secondary of T1 and on lead 58 will be summed on the inverting input lead 52 of comparator 42. If the voltage across capacitor C1 is larger than the voltage across capacitor C2 the voltage on lead 57 to be summed on the negative inverting input lead 52 of comparator 42 will start from a lower value (i.e., a more negative value) thereby extending the time period that switching transistor Q1 remains on and thereby correcting the imbalance shown in the current pulse widths in FIG. 3.
The time at which the voltage on the inverting input lead 52 to comparator 42 matches the voltage on the non-inverting input lead is known as the "current compare time" or the "current compare point". Immediately after comparator 42 pulls down the voltage on its output lead and shuts off whichever one of transistors Q3 and Q4 were on, the pulse resulting from the shutting off of this transistor is transmitted through capacitor C9 or C10 and on lead 55 (see FIG. 5g) to turn on transistor Q5. The turning on of transistor Q5 grounds lead 57 through diode D8. Actually lead 57 is not quite grounded but rather adopts a voltage of about 0.6 to 0.7 volts beneath ground because of the effect of the two forward biased diodes D9 and D10. At the same time, the voltage across R9 disappears and therefore Q7 is turned off. The turning off of Q7 allows R2 to pull down and turn on Q6, which pulls up lead 57 one diode drop below ground. The restoration of lead 57 and thus capacitor C6 to this voltage prevents a bias from building up across capacitor C6 which would result in a shift in the maximum current comparison point on lead 52 to comparator 42.
Variation in line voltage (i.e., the voltage on nodes 51a and 51b) will not affect the maximum output current produced by the power supply on nodes 50a and 50b. Should the voltages across capacitors C1 and C2 change because of a change in line voltage, these voltages will be reflected through transformer T1 to the secondary of choke T3 and will result in a change in voltage on line 57 to a more negative value. However, this is a transient effect and at the end of a half cycle, the turning on or Q5 and Q6 will bring line 57 back to approximately ground.
One feature of this invention of importance is that the feedback circuit which provides a measure of the DC voltage across capacitor C1 and C2 is DC isolated by the power transformer T1 in the power supply and by the choke T3 on the output of the power supply. Thus transformers T1 and T3 provided double isolation of the feedback path insuring that the power supply still meets UL requirements for isolation without requiring additional feedback paths.
As an additional feature, the balance circuit is not referenced to the output terminals 50a, 50b. The balance circuit 48 is inherently isolated from the output terminals 50a and 50b and thus allows the grounding of the balance control circuit 48 to be done independently of the grounding of the output terminals 50a and 50b.
FIG. 2b illustrates a full bridge capacitor coupled switching circuit also capable of being used with the balance circuit of this invention. In operation transistors Q1 and Q4 are turned on, allowing current I 1 to charge capacitor C1. Then transistors Q1 and Q4 are turned off and transistors Q2 and Q3 are turned on, allowing current I 2 to discharge capacitor C1. Any imbalance in the times I 1 and I 2 are on will cause capacitor C1 to charge fully as a result of the dominant current and thus latch up. The balance circuit of this invention shown in FIG. 4 will prevent this.
While one embodiment of this invention has been described, other embodiments will be obvious in view of the above disclosure. | A control circuit is provided for controlling the on-time of a pair of switching transistors in a half bridge converter. The control circuit includes a first comparator for comparing the converter output voltage with a reference voltage. The control circuit also includes a circuit which generates a first signal indicative of the current through the primary winding of the converter output transformer. Also included is a circuit which generates a second signal indicative of the on-time of one of the switching transistors exceeding the on-time of the other switching transistor. The first and second signals are averaged and compared with the output voltage of the first comparator by a second comparator. The second comparator controls the on-time of the switching transistors. In this way, any imbalance in the on-time of the switching transistors is corrected by the control circuit. | 7 |
The present application is a continuation-in-part of International Application PCT/US02/020360, filed Jun. 28, 2002, and claims the benefit of U.S. Provisional Application No. 60/301,417, filed Jun. 29, 2001, the disclosures of both of which documents are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to the application of adhesive to a surface.
When applying adhesive to a surface, for example for installation of ceramic tile or floor coverings, it is common practice to place a quantity of the adhesive on the surface and to then spread the adhesive with a notched trowel in order to create adhesive beads that are spaced apart. This procedure is time-consuming and inefficient, and requires a substantial amount of clean-up work.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a novel adhesive dispensing cartridge that is disposable or refillable, and an adhesive applicator composed of the cartridge, a cartridge holder having a receptacle for retaining the cartridge and a movable drive element carried by the holder and coupled to the cartridge to force adhesive out of the cartridge.
The adhesive dispensing cartridge according to the invention is composed of a housing enclosing a space for containing a quantity of adhesive, the housing having a front end and a rear end, an adhesive delivery element connected at the front end of the housing, the element being composed of a plurality of teeth spaced apart by recesses and being provided with a plurality of adhesive flow passages extending between the space enclosed by the housing and the recesses, and a plate disposed in the space at the rear end of the housing, the plate cooperating with the housing to contain the adhesive and being movable within the housing toward the front end to force adhesive from the space and through the flow passages.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective front view of one embodiment of a cartridge according to the invention.
FIG. 2 is view similar to that of FIG. 1 showing the cartridge of FIG. 1 provided with a movable protective cap.
FIG. 3 is a perspective rear view of the cartridge of FIG. 1 .
FIG. 4 is a detailed view of one end of a component of the cartridge of FIGS. 1–3 .
FIG. 5 is a cross-sectional view taken along line V—V of FIG. 1 .
FIG. 6 is a detailed view of a front portion of an element of the cartridge of FIGS. 1–5 .
FIG. 7 is a bottom plan detail view of the portion shown in FIG. 6 .
FIG. 8 is a perspective view depicting adhesive beads being produced by an applicator according to the invention.
FIG. 9 is a simplified side elevational, cross-sectional view of a first embodiment of an applicator equipped with a cartridge according to the present invention.
FIG. 10 is a top plan view of the applicator shown in FIG. 9 .
FIG. 11 is a front perspective view of the applicator.
FIG. 12 is an elevational view of one component of the applicator.
FIG. 13 is a simplified schematic diagram of a circuit for controlling operation of the applicator.
FIGS. 14 and 15 are, respectively, a perspective view and a side elevational view of a second embodiment of an applicator equipped with a cartridge according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a cartridge 10 according to the present invention is shown in FIGS. 1–3 . This cartridge is composed essentially of a housing 12 having the general form of a rectangular prism and composed of a front end 16 , a rear end 18 , and upper side, a lower side, (not visible) and two lateral sides. At least two of the sides are each provided with at least one inwardly projecting land 24 that extends between ends 16 and 18 .
Front end 16 is provided, along the lower edge thereof, with an adhesive dispensing element 28 formed to present a series of downwardly projecting teeth 30 spaced from one another by recesses 32 .
Housing 12 has a hollow interior that is filled with an adhesive to be dispensed and rear end 18 is constituted by a plate that is movable relative to the remainder of housing 12 toward front end 16 so as to force adhesive out of dispensing element 28 , as will be described in greater detail below. Thus, plate 18 will function as a primary plunger.
FIG. 2 , which is a view similar to that of FIG. 1 , shows element 28 , covered with a protective cap 34 when cartridge 10 is not in use.
As can be seen in FIG. 3 , plate 18 is provided at its edge with grooves that mate with lands 24 .
FIG. 4 is a detail view of one end of plate 18 , as viewed from within housing 12 . According to one optional feature of the invention, plate 18 is provided with a flange 36 that extends around the entire periphery of plate 18 and projects into housing 12 . Flange 36 and the grooves that mate with lands 24 cooperate to guide plate 18 so that it remains parallel to font end 16 while being displaced. In addition, flange 36 can be formed to serve as a seal and to prevent plate 18 from backing out of housing 12 .
FIG. 5 is a cross-sectional view taken along line V—V of FIG. 1 . FIG. 5 shows that housing 12 encloses a space, or chamber, 40 containing adhesive to be dispensed. Element 28 is provided with a plurality of adhesive flow passages 42 each extending between chamber 40 and the base of a respective one of recesses 32 .
Further details of dispensing element 28 are shown in FIGS. 6 and 7 . FIG. 6 , in particular, shows that, in a preferred embodiment of the invention, each tooth has a flat bottom surface, while each recess 32 has a rounded bottom. FIG. 7 shows the location of the outlet end of each passage 42 at the base of its respective recess 32 .
FIG. 8 depicts adhesive beads 46 produced by an applicator according to the invention. In order to produce these beads, it is only necessary to move cartridge 10 rearwardly, i.e., in the direction from front end 16 to rear end 18 , while simultaneously displacing plate 18 toward front end 16 . As long as the lower surfaces of teeth 30 remain in contact with, or close to, the surface 50 to which the adhesive is to be applied, beads 46 will have cross sections corresponding to those of recesses 32 .
Cartridge 10 may be made of any suitable material, such as aluminium, and may be either reusable or disposable.
FIG. 9 is a simplified side elevational, cross-sectional view of an applicator equipped with a cartridge 10 according to the present invention. The applicator is a hand-held device having a main housing 60 from which extends a handle 62 . The rear end of main housing 60 is provided with a receptacle for a battery 64 , which is preferably rechargeable.
The front end of main housing 60 constitutes a cartridge receptacle 66 in which a cartridge 10 will be held when adhesive is to be dispensed. Cartridge 10 and receptacle 66 are dimensioned so that when cartridge 10 is held in place in receptacle 66 , these lower surfaces of teeth 30 will be substantially flush with the lower surface of receptacle 66 . Cartridge 10 will be held in place in receptacle 66 by a fastening bar 68 that extends across, and is in contact with, front end 16 .
Housing 60 contains and electric drive motor 72 having an upward shaft connected to a transmission 74 . Transmission 74 is, in turn, coupled to a bevel gear arrangement that includes an output 76 . Gear 76 is coupled to cogged, or toothed, drive rod 80 . Gear 76 and rod 80 thus form a rack and pinion mechanism. Rod 80 is preferably a solid rod having a square cross section and is guided for longitudinal movement in two guides 86 and 88 that are fixed in housing 60 .
The output end of rod 80 carries a secondary plunger 90 that preferably corresponds closely in shape, but is slightly smaller then plate 18 . Rotation of motor 72 thus produces linear movement of rod 80 to advance plunger 90 and plate 18 into cartridge 10 , thus forcing adhesive through passages 42 and into recesses 32 .
The operation of motor 72 is controlled by a manually operable variable speed trigger switch 92 and a forward/reverse switch 94 in handle 62 . Trigger switch 92 is coupled to battery 64 and motor 72 in order to cause the speed of motor 72 to vary as a function of the degree of depression of trigger 92 . Circuitry for performing such an operation is already well known in the art. The output shaft of motor 72 may also carry a fan 98 that will produce a flow of air for cooling motor 72 .
FIG. 10 is a top plan view of the applicator shown in FIG. 9 and shows bar 68 pivotally mounted to a hinge 102 . The free end of bar 68 engages a latch 104 that holds bar 68 in a closed position when the applicator is in use.
FIG. 11 is a front perspective view of the applicator, with no cartridge being provided in receptacle 66 . Housing 60 is provided with a series of vents 106 that provide ventilating airflow. There may be three such vents along each side of housing 60 .
FIG. 12 shows one example of latch 104 , which is composed essentially of a mounting plate 110 , tension spring clips 112 and clip release levers 114 . When levers 112 are in their normal position, as shown in FIG. 12 , bar 68 is held in a closed condition. In order to release bar 68 , for example in order to replace a cartridge 10 , the user deflects levers 114 toward the rear, thus moving levers 112 away from one another.
FIG. 13 is a simplified schematic diagram illustrating the connection of battery 64 to motor 72 via trigger 92 . Trigger 92 is coupled to conventional control circuitry 120 that will vary the power supplied to motor 72 as a function of the degree of depression of trigger 92 . By way of non-limiting example, circuitry 120 could include a simple potentiometer that varies the magnitude of the voltage supplied to battery 72 , or could be a SCR control circuit that varies the rate of application of dry voltage pulses to motor 72 . Circuit 120 could also be constructed according to the teachings of U.S. Pat. No. 4,649,245, Lessig, III et al, the disclosure of which is incorporated herein by reference. Those skilled in the art will be readily aware of other types of control circuits that can be employed. Control circuit 120 can be coupled in a suitable manner to switch 94 to allow for control of the direction of rotation of motor 72 .
In order to dispense adhesive with the applicator according to the present invention, it is only necessary for the user to rest the bottoms of teeth 30 on the work surface and place motor 72 into operation while drawing the applicator rearwardly along the surface and controlling the speed of motor 72 in order to coordinate the rate at which adhesive is dispensed with the rate of displacement of the applicator. The application of beads to the work surface may be improved if the applicator is held at a slight angle to the work surface such that the leading edge, i.e., the edge furthest from front end 16 , of the teeth are in contact with the surface and the bottom surfaces of the teeth form an angle of the order 5° with the work surface.
When the supply of adhesive in a cartridge has been exhausted, it is only necessary to replace the cartridge in order to continue adhesive application. The empty cartridge may be thrown away, since it is a relatively inexpensive component.
If, at the end of an adhesive application task, useable adhesive remains in the cartridge, cap 34 may be placed over element 28 in order to prevent accidental escape of adhesive and maintain the adhesive in a condition for future use. Cap 34 could be configured to additionally engage the rear edge of element 28 in order to completely seal the spaces defined by recesses 32 .
A second embodiment of the invention is shown in FIGS. 14 and 15 . This embodiment has three novel features, any one or more of which could be incorporated into the embodiment of FIGS. 1–13 . These features are: a curved handle fastened at both ends to the applicator housing; a multi-speed motor control; and a cartridge fastening gate that is connected to the front of the housing by a hinge having a horizontal axis.
FIGS. 14 and 15 show a housing 140 with an integrally-formed, curved handle 144 that is fastened at both ends to the upper surface of housing 140 . Handle 144 is shaped to provide a generally D-shaped opening for receiving one hand of the user.
This curved handle construction provides two important advantages. Firstly, it helps to rigidify the entire housing. This is an important factor considering the length of the applicator and the inherent weight of a full cartridge, which can be as much as 13.5 lbs.
The second advantage is that it allows improved control of the applicator. Given the working weight of a loaded applicator, two-handed control is a necessity. The D-handle construction facilitates this efficiently by the provision a handgrip 148 at the front of the handle, and thus at the front of the applicator, for the other hand of the user. Preferably, handgrip 148 is placed as far forward and as low to the housing body as practically possible. The resulting forward hand position affords the user maximum control when using the applicator for either a vertical wall or horizontal floor application. Also preferably, the handle is positioned and dimensioned so that the center of gravity of the applicator, when loaded, is between the fore and aft grips.
The multi-speed motor control, as opposed to the continuously variable speed control of the first embodiment, provides a major advantage in that it allows the user to rely on any one of several recommended pre-set plunger speeds to govern the flow of adhesive from the cartridge. These speeds correlate directly with different cartridges filled adhesives having different flow characteristics applicable to the adhesion of specific materials. For example, adhesives for ceramic tile, vinyl and linoleum flooring, and laminate wood flooring may have different consistencies such that a different plunger speed is optimum for each adhesive. This feature is beneficial because and applicator according to the invention is intended to accept cartridges pre-filled with adhesives of different consistencies and having different sized application holes and teeth. The ability to select a plunger speed that is preset for a given type of adhesive considerably cuts down on the immediate skill, or learning curve, required when using this applicator.
In this embodiment, speed control 120 could be constructed in the manner described in U.S. Pat. No. 5,802,248, Miller et al, the disclosure of which is incorporated herein by reference.
The multi-speed motor control employs a speed setting switch 152 and an operating trigger 156 , which may both be installed in handle 144 , although they could be placed elsewhere on housing 140 . Switch 152 may have two or more preset speed settings and, if desired, a variable speed setting allowing the plunger speed to be varied as a function of the amount of trigger depression, as in the first-described embodiment,
The cartridge fastening gate of the second embodiment, shown at 168 in FIGS. 14 and 15 , is mounted to housing 140 by a hinge 170 and is held in a closed position by pressure release latches 174 (one of which is not visible) at opposed ends of gate 168 . Fastening gate 168 may have a generally rectangular form, with a long dimension and a short dimension, and is connected to housing 140 to pivot about an axis parallel to the long dimension, or about an axis that is horizontal when the applicator is in a position to apply adhesive to a floor surface. Pressure release latches 174 are disposed at the short sides of gate 168 .
Fastening gate 168 provides important advantages. One of these is that it provides a complete and solid surface for the front of the cartridge to push against when the cartridge is under pressure during adhesive application. Upon release, the gate flips up and out of the way, staying close to the applicator, as opposed to the bar design of FIGS. 9–12 hinged on one side, which renders the hinge vulnerable to breakage at the hinge point when in the open position.
Latches 174 can be devices that are widely used, such conventional portable power applicator battery pack releases.
The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without undue experimentation and without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. The means, materials, and steps for carrying out various disclosed functions may take a variety of alternative forms without departing from the invention.
Thus the expressions “means to . . . ” and “means for . . . ”, or any method step language, as may be found in the specification above and/or in the claims below, followed by a functional statement, are intended to define and cover whatever structural, physical, chemical or electrical element or structure, or whatever method step, which may now or in the future exist which carries out the recited function, whether or not precisely equivalent to the embodiment or embodiments disclosed in the specification above, i.e., other means or steps for carrying out the same functions can be used; and it is intended that such expressions be given their broadest interpretation. | A reusable or disposable adhesive dispensing cartridge including a housing for containing a quantity of adhesive, an adhesive delivery element connected to the housing and having a plurality teeth spaced apart by recesses and a plate movably mounted in the housing to force adhesive from the housing and through flow passages that extend between the interior of the housing and the recesses. An adhesive applicator includes a cartridge holder for retaining the cartridge and a movable drive element coupled to the cartridge plate to move the plate in a direction to force adhesive out of the housing and through the flow passages. | 1 |
TECHNICAL FIELD OF THE INVENTION
The invention relates to integrated circuits, and more specifically to avoiding interference between different components within such circuits.
BACKGROUND
Numerous integrated circuits (IC) are used for mixed signal purposes. That is, such circuits include both analog and digital components. Specifically, certain such mixed signal circuits include analog circuitry that operates at extremely high frequencies, for example, radio frequencies (RF), and digital circuitry that operates at baseband frequencies. Because of the presence of both analog and digital circuitry within such IC devices, there is a potential for interference between the analog and digital components.
While various sources of such interference may exist, one particular source of interference may be interference caused by harmonics of baseband clock frequencies that interfere with RF frequencies within the IC device. Accordingly, a need exists to reduce or prevent such interference.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a receiver in accordance with one embodiment of the present invention.
FIG. 2 is a graphical representation of a signal spectrum in accordance with one embodiment of the present invention.
FIG. 3 is a graphical representation of a signal spectrum in accordance with another embodiment of the present invention.
FIG. 4 is a block diagram of a portion of a system in accordance with one embodiment of the present invention.
FIG. 5 is a flow diagram of multiple tuners in accordance with one embodiment of the present invention.
SUMMARY OF THE INVENTION
One aspect of the present invention includes a method of adjusting a clock frequency for a baseband component of a system to avoid interference with a RF signal, such as a signal channel or a local oscillator (LO) frequency used by a receiver of the system.
Another aspect of the present invention includes a method of receiving a RF signal spectrum in a receiver; mixing the RF signal spectrum with a first LO frequency to obtain a first downmixed signal; and converting the first downmixed signal to a first digital signal using an analog-to-digital converter (ADC) having an adjustable clock frequency selected to avoid interference with the first LO frequency.
In yet another aspect of the present invention, an apparatus is provided that includes a clock generator to generate a baseband clock frequency; and a controller coupled to the clock generator to adjust the baseband clock frequency to avoid interference with a RF frequency. Such an apparatus may be used in a system that includes a RF circuit to receive a satellite spectrum and to mix the satellite spectrum with a first LO frequency to obtain a first downconverted signal; and a first baseband circuit coupled to receive and to process the first downconverted signal, the first baseband circuit having at least one component to operate at the adjustable baseband clock frequency.
DETAILED DESCRIPTION
Referring to FIG. 1 , shown is a block diagram of a system in accordance with one embodiment of the present invention. As shown in FIG. 1 , system 10 may be, for example, a receiver for use in a RF system such as a satellite receiver for use in a set-top box or other television tuner. While discussed primarily herein as used in such a satellite system, it is to be understood that other embodiments of the present invention may be used in connection with other RF systems, such as cellular telephones, radios, other communication systems and the like.
As shown in FIG. 1 , system 10 receives an incoming signal 20 at a low noise amplifier (LNA) 30 . The resulting amplified signal 35 may then be input into a mixer 40 , where the RF signal is mixed with a local oscillator (LO) frequency (f LO ) provided by LO circuitry 50 .
The resulting downconverted signal 55 may be provided to baseband circuitry for further processing. For example, downconverted signal 55 may be sent to an analog-to-digital converter (ADC) 60 for conversion from an analog signal to a corresponding digital signal 65 . Digital signal 65 may then be provided to a digital signal processor (DSP) 70 for desired processing. In one embodiment, a wide-band ADC 60 may receive a coarsely tuned signal 55 and provide a digital output to DSP 70 , which may be a tunable digital filter that in turn outputs digital baseband signals 75 .
While such a DSP may take various forms, in certain embodiments, such a digital signal processor may include various circuitry for tuning, filtering, and processing digital signals. For example, such circuitry may include clock and data recovery circuitry, digital tuning circuitry, digital filtering circuitry, and digital decoding circuitry, for example.
The processed signals 75 , which may be digital baseband signals, may be provided to additional circuitry (either on the same integrated circuit (IC) or to different circuitry) for further processing. For example, as shown in FIG. 1 , the digital baseband signals 75 and the clock frequency may be provided to an input/output (I/O) circuit 96 . Such an I/O circuit may be used to transfer both the digital data (output as data 98 ) and the clock frequency to other circuitry within a system. In various embodiments, different components may be included in such additional circuitry, including additional processing components, audio and video components and the like. In such manner, in certain embodiments, the clock frequency may be provided for use in other system components, in addition to the digital data.
Alternately, in other embodiments DSP 70 may sufficiently process incoming signals for their intended purpose. In the embodiment shown in FIG. 1 , all components may be housed within a single integrated circuit, although the scope of the present invention is not so limited. Further, while not shown in FIG. 1 , in other embodiments multiple tuners may be present within a single IC. Such multiple tuners may each include the same RF and baseband circuitry shown in FIG. 1 .
As further shown in FIG. 1 , a clock frequency (f CLK ) may be provided by a clock generator 80 and used as clock signals for baseband components, including ADC 60 and DSP 70 (or other such baseband circuits). While shown in FIG. 1 as providing the same clock signal to both ADC 60 and DSP 70 , in other embodiments, different clock signals may be provided to these or other digital circuits.
There is a potential for interference between a harmonic of such a baseband or digital clock frequency and RF frequencies used in a system. For example, a digital clock frequency of 100 megahertz (MHz) may generate a harmonic (e.g., a tenth harmonic) that interferes with a RF frequency (e.g., a one gigahertz (GHz) frequency). Such an RF frequency may be within a band of a received signal (e.g., a received signal channel), a LO frequency, or any other RF frequency used in or received by the system. Thus it may be desirable to adjust the digital clock frequency to avoid interference at RF frequencies. Accordingly, a clock controller 90 may be used to control clock generator 80 so as to avoid this interference. While frequency planning is understood in the field of RF design, what is different in the embodiment is the fact that in certain broadband RF applications no single clock selection will suffice to eliminate the interference problem for all channels. Thus the clock frequency may be dynamically adjusted to adjust harmonics away from the “current” desired channel or “current” LO frequencies.
As shown in FIG. 1 , clock controller 90 may receive the LO frequency output from LO circuitry 50 and the clock frequency output from clock generator 80 . Of course, in other embodiments, other RF frequencies may be provided to clock controller 90 for comparison to a digital clock frequency. Based on analysis of these frequencies it may be determined whether there is a potential for interference therebetween. If such interference is likely, clock controller 90 may provide control signals 95 to clock generator 80 to adjust the clock frequency accordingly to avoid interference.
In one embodiment, clock controller 90 may include logic functionality to analyze an LO frequency used to downmix an incoming signal, and a baseband clock frequency to determine whether a potential exists for interference therebetween. For example, in one embodiment clock controller 90 may include a combination of hardware, software and/or firmware to analyze the incoming frequencies and determine whether any adjustment to the baseband clock frequency is desired.
In various embodiments, it may be determined whether a harmonic of the clock frequency (or frequencies) is near a desired signal channel. In such embodiments, “near” means that the two frequencies are close enough in frequency that undesired interference may occur if the clock frequency is not adjusted. While what is considered to be near a given signal may vary in different embodiments, in certain embodiments, if the harmonics are within between approximately 40 MHz and 80 MHz of a signal channel (or its LO frequency), the clock frequency may be adjusted.
In other embodiments, the clock frequency may be adjusted so that its harmonics are separated from a LO frequency by at least an amount equal to a crosstalk region. While the width of such a crosstalk region may vary, in certain embodiments such a crosstalk region may be between approximately 40-80 MHz wide, although the scope of the present invention is not so limited.
In certain embodiments, adjusting the clock frequency may be effected using software (or a combination of software, firmware and hardware) that may be executed within a system, such as a receiver, cellular telephone, or the like. For example, in the embodiment of FIG. 1 , such software may be implemented within clock controller 90 . Such embodiments may include an article in the form of a machine-accessible storage medium, which may include, but is not limited to, floppy diskettes, optical disks, CD-ROMs, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, magnet or optical cards, flash memory, or other type of media/machine-accessible storage medium suitable for storing electronic instructions, onto which there are stored instructions and data that form a software program to perform such methods of avoiding interference.
Thus control signals 95 may be used to cause clock generator 80 to adjust its output, namely the clock frequency, f CLK . While clock generator 80 may take different forms in various embodiments, in one embodiment, clock generator 80 may include a crystal oscillator, such as a quartz crystal that generates a reference frequency. Such a reference frequency may then be processed, for example, by dividing the reference frequency and then passing the divided output to clock frequency generation circuitry, such as a phase lock loop (PLL), a voltage controlled oscillator (VCO), or other such circuitry. While shown in the embodiment of FIG. 1 as generating a single clock frequency, it is to be understood that clock generator 80 may output multiple different baseband clock frequencies. Using feedback from control signals 95 , clock generator 80 may accordingly adjust its output clock frequency (or frequencies) to avoid interference with RF frequencies, such as one or more signal channels of a satellite receiver.
In such manner, the clock frequency may be adjusted to move interfering tones away from, for example, a desired RF signal channel. Because digital clock frequencies exist at a much lower frequency than desired RF channel frequencies, by adjusting the digital clock frequency by a small amount, significant changes in harmonics of the clock frequency may be realized, thus avoiding interference at the desired RF signal frequency.
Referring now to FIG. 2 , shown is a graphical representation (not drawn to scale) of a signal spectrum in accordance with one embodiment of the present invention. As shown in FIG. 2 , a digital clock frequency is present at f CLK . For purposes of illustration, it may be assumed that f CLK is at 100 MHz. Further shown in FIG. 2 is a RF frequency (f LO ) corresponding to a LO frequency to be used for tuning a desired signal channel of an RF spectrum, for example, a television channel in a satellite television receiver. For sake of illustration, assume that the LO frequency is at two GHz. Thus, the twentieth harmonic of the clock frequency (i.e., ωf CLK ) falls on the LO frequency (not shown precisely in FIG. 2 for ease of illustration) and therefore may cause interference.
Still referring to FIG. 2 , if instead the clock frequency is adjusted by a small amount (i.e., a Δf), the harmonics of the adjusted clock frequency may be far enough away from the desired LO frequency such that no interference exists. For example, assume that Δf equals 2 MHz. Thus, at two times the clock frequency, a Δf of four MHz exists, and at the twentieth harmonic, a total change in frequency of 40 MHz exists (i.e., ωΔf). In such manner, interference may be avoided between the LO frequency and the harmonics of the clock frequency. The importance of this is that only small adjustments in the clock frequency may be used to avoid interference. In such manner, any costs associated with developing flexible digital logic (due the higher speed needed) and slightly larger tuning range needed for the PLL are reduced. Similarly, any cost to analog blocks that require the f CLK , such as ADCs and digital-to-analog converters (DACs) is minimal. The designer only has to add a few percentage points of margin to such designs.
While the amount that a clock frequency may be shifted may vary in different embodiments, in certain embodiments a frequency shift of a small percentage may be sufficient to avoid interference at RF signal levels. Thus in various embodiments, a frequency shift between approximately 0.5% and 5% may be effected, and in particular embodiments, approximately a 2% frequency shift may be used.
In other embodiments, instead of a fixed percentage change to a clock frequency, a continuous phase modulation (CPM) of the clock frequency may be implemented. For example, a slow but large modulation of a clock frequency may be effected to avoid interference at RF signal levels.
Referring now to FIG. 3 , shown is a signal spectrum in accordance with one embodiment of the present invention. As shown in FIG. 3 , digital interference may create a tone in a desired signal channel at a frequency somewhere between 1 and 2 GHz. For example, shown in FIG. 3 is an undesired noise having a value of −A dbm in a given desired signal channel having a bandwidth of 1.2 MHz. By performing CPM of the digital clock frequency that causes this noise, the noise energy may instead be spread out over a wider frequency range, thus lowering the signal level of the noise to an acceptable level.
In certain embodiments, modulation of the clock frequency may be performed slowly. For example, for a clock frequency of 100 MHz, the modulation rate may be, for example, 100 kilohertz (KHz). However, the actual modulation of the clock frequency may be larger than a fixed adjustment to the clock frequency, as described above. For example, in certain embodiments a larger percentage of modulation may occur. As an example, for a digital clock frequency of 100 MHz, the clock frequency may be modulated by 5 or more MHz. In such manner, noise that may occur at a desired RF frequency may be spread out over a wider frequency range, such that the noise becomes insignificant.
Referring now to FIG. 4 , shown is a block diagram of a system in accordance with another embodiment of the present invention. As shown in FIG. 4 , system 200 may be a portion of a receiver, for example, a satellite receiver or the like. Only a portion of such a receiver is shown for purposes of the discussion of FIG. 4 . However, it is to be understood that additional components may be present within such a receiver.
As shown in FIG. 4 , an incoming downconverted analog signal 205 may be provided to an ADC 210 for digital conversion. The resulting digital signal 215 may be provided to a clock and data recovery unit (CDR) 220 . CDR 220 may be used to recover a clock from the incoming signal as well as to sample the data present in the signal with the recovered clock. Thus the output of CDR 220 may be an encoded digital data stream 225 that is provided to a decoder 230 . Decoder 230 may decode the encoded signals and provide a decoded digital output 235 to an input/output (I/O) circuit 250 . For example, in one embodiment, decoder 230 may be a Viterbi decoder, although the scope of the present invention is not so limited.
As shown in FIG. 4 , each of the digital circuits, including ADC 210 , CDR 220 , and decoder 230 are provided a digital clock frequency (f CLK ), generated from clock generator 240 . While shown for ease of illustration in FIG. 4 as receiving the same clock frequency, it is to be understood that in other embodiments some or each digital circuit may receive its own clock frequency. Further shown in FIG. 4 is a clock controller 245 which may be used to provide control signals to clock generator 240 to modify, modulate, and/or adjust the clock frequency to avoid RF interference as described herein.
As further shown in FIG. 4 , the decoded digital data 235 and the clock frequency may be provided to an I/O circuit 250 . Such an I/O circuit may be used to transfer both the digital data and the clock frequency to other circuitry within a system. In such manner, in certain embodiments, the variable rate clock frequency may be provided for use in other system components, in addition to the decoded data.
However, it may instead be desired to provide a fixed rate of digital data out of system 200 . To effect such a fixed data rate while using variable clock frequencies within system 200 , a variable rate interpolator may be present within I/O circuit 250 , for example, to digitally resample the data to the desired output frequency (e.g., an original clock frequency of one or more baseband components).
As discussed, adjustment to a baseband clock frequency may occur for various RF systems. For example, set-top box satellite receivers, including low intermediate-frequency (IF) architectures, and direct down conversion (DDC) architectures may utilize such clock frequency adjustments.
Similarly, clock frequency adjustment may be used in a receiver that analog coarsely tunes signal channels. In such an embodiment, by fine tuning a coarsely tuned channel spectrum, the receiver does not mix the desired channel down to a fixed target IF frequency and then mix the desired channel to DC. Rather, such an implementation uses analog coarse tune circuitry to mix the desired channel down to a variable location within a frequency range around DC, and then digital conversion and digital filtering is performed directly on the coarsely tuned channel spectrum.
Further, such adjustments may be made in multi-tuner environments. In such environments, multiple tuners may be present to tune multiple signal channels as shown in FIG. 5 . For example, two or more such tuners 310 and 320 may be present to tune multiple television channels received from a satellite source 305 . Accordingly, multiple LO generation circuits 315 and 325 may be present. Furthermore, multiple signal channels may be received and tuned. Thus, one or more digital baseband clock frequencies may be adjusted to avoid interference with the signal channels and/or LO frequencies used in tuning such signal channels. In such embodiments, clock controller circuitry 330 may receive multiple RF frequencies, for example, multiple LO frequencies and use such frequencies to determine whether baseband clock frequency adjustment is needed, and if so, what adjusted clock frequency should be generated.
While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention. | Various embodiments of the present invention include methods and apparatus for receiving a radio frequency (RF) signal spectrum in a receiver; mixing the RF signal spectrum with a first local oscillator (LO) frequency to obtain a first downmixed signal; and converting the first downmixed signal to a first digital signal using an analog-to-digital converter (ADC) having an adjustable clock frequency selected to avoid interference with the first LO frequency. The adjustable clock frequency may be adjusted by a predetermined amount, by phase modulation, or in other manners. | 7 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates in general to the field of thread winding equipment, in particular, to a new and useful device for transferring cops or bobbins of yarn or the like from a bobbin container to a bobbin receptacle on a spooling frame.
Spooling frames have a whole series of bobbin holders positioned next to one another holding preferably a plurality, e.g. five or six, of bobbin receptacles. Into these receptacles the bobbins or cops of yarn to be unwound are inserted in the spooling frame. One after the other the bobbins are then unwound, and in the process bad spots are removed from their yarn or the like, and after the associated "refinement" the yarn is rewound into a new bobbin, particularly a crosswound bobbin. The processes are accomplished relatively quickly, for which reason it is a matter of concern that a number and particularly the maximum possible number of bobbins should be standing ready at all times in each bobbin holder. The insertion of the bobbins in the bobbin receptacles is a relatively time-consuming task, particularly if the bobbins are inserted by hand.
SUMMARY OF THE INVENTION
The object of the invention, therefore, is to create a device of the abovementioned kind by means of which all bobbin receptacles of the spooling frame can be automatically loaded, so that after one bobbin is emptied, the process can continue with the next bobbin with the least possible loss of time.
Accordingly, another object of the invention is to provide a device for transferring bobbins of yarn from a bobbin container to a bobbin receptacle on a spooling frame, comprising a device frame, at least two slide gate units lying opposite one another at a distance equal to the length of a bobbin, each for supporting one end of bobbins in a row of bobbins, a cross conveyor connected for movement to the device frame under the slide gate units, a righting chute at a discharge end of said cross conveyor, said righting chute being connected to the device frame and being positioned under the slide gate units, the righting chute having a closeable delivery end which is positionable in front of a receptacle for bobbins in the spooling frame.
The bobbin container holds a large number of bobbins, one hundred, for example. With the aid of a box slide associated with the lower end of the bobbin container, a given number of bobbins in the form of a row or layer of bobbins are transferred, after the corresponding actuation of the box slide, to the two slide gate units, each of which supports one end of all the bobbins in that row of bobbins. The bobbins lie in the bobbin box preferably already sorted so that in the case of conical bobbin cores all the thicker ends of the bobbin cores are oriented toward one slide gate unit, while all the thinner ends are oriented toward the other. At least one cross-conveyor is located in operating position underneath the slide gate units.
Whereas the cops or the like are moved from above to below, in other words, more or less in a vertical direction, when being transferred from the bobbin container or box to the slide gate units and from them onto the cross-conveyor or conveyors, each of the cross-conveyors transports them in a horizontal direction to the righting chute or the like that is located at its delivery end. They fall, preferably by their own weight, from the cross-conveyor onto the righting chute, which has a longitudinal axis that is inclined with respect to the plane of the cross-conveyor. For this reason, the transfer to the righting chute is accompanied by a certain righting or erection of the cop passing down the chute. Since, however, the righting chute is on an angle with the horizontal that does deviate substantially from 90°, the cops passing down the chute do not assume a vertical but rather an inclined position. Since the delivery end of the righting chute can be closed, the cop that reached the bottom of the chute cannot leave it until its delivery end is released. This does not happen until the the delivery end is positioned over a bobbin receptacle of the spooling machine and that bobbin receptacle is empty. All movements are meaningfully coordinated with one another, to insure, for example, that another cop does not fall into the righting chute until it has first been unloaded. Similarly, the slide gate units must be completely emptied before a new row of bobbins can be transferred from the bobbin container.
A further object of the invention is to provide a device for transferring bobbins of yarn from a bobbin container to a bobbin receptacle of a spooling frame which is simple in design, rugged in construction and economical to manufacture.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference is made to the accompanying drawings and descriptive matter in which preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings depict one embodiment of the invention by way of example. In the drawings:
FIG. 1 is a truncated front view of the inventive device;
FIG. 2 is a side view of the device taken in the direction of arrow B in FIG. 1;
FIG. 3 is a vertical sectional view taken through the slide gate unit; and
FIG. 4 is a truncated top view of the slide gate unit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The device in the embodiment used as an example is symmetrically constructed around the vertical plane 1 (FIGS. 1 and 4). In a bobbin container 2 suggested in FIG. 2 are a rather large number of bobbins of yarn or the like of the kind known as cops 3. By means of this device they are to be transferred to the bobbin holder 4, of a spooling frame 5, the spooling frame 5 possessing a whole row of such bobbin holders with a plurality of bobbin receptacles 6, in particular arranged in a circle. When a bobbin is transferred to one of these bobbin receptacles 6, the bobbin holder, which is preferably rotatable, is turned further on its axis 7 until the next bobbin receptacle moves up into place. If, in the case of a conical bobbin core 8, for example, the thicker end of the core should be on the bottom 9 of the bobbin holder 4, the bobbins must already be so oriented in the bobbin container 2. The device is equipped with wheels, sliding blocks or the like, not depicted in detail, with which it can be moved along the spooling frame perpendicular to the projection plane of FIG. 2. An appropriate device makes sure that it is oriented in precisely predetermined position to each bobbin holder on the frame.
When a box slide (not shown) is opened, a given number of cops 3 fall out of the bobbin container 2 onto the tops of slide gate units 13 and 14. When these slide gate units, which are mounted for movement on a frame, are actuated in a manner described below in greater detail, the cops or bobbins drop onto at least one, but in the present embodiment two cross-conveyors 11, 12 positioned lengthwise one after the other, conveying in the directions indicated by the arrows 16 and 17. At the delivery end 18 of each cross-conveyor is a righting chute 10, in the present emobdiment at an angle of roughly 45° to the horizontal. Its delivery end 15 is correlated with a bobbin holder 4 and a bobbin receptacle 6, as shown in FIG. 2. For this purpose, the delivery end can be adjusted, at least in the direction indicated by the double arrow 19, by means of a retaining and adjustive device 20. Each slide gate unit 13, 14 has a slide 21, 22, which is roughly U-shaped in cross-section and that extends parallel to the carrying surface 23 of the conveying elements 24 of the cross-conveyors 11, 12. The two legs of the U run roughly parallel to the carrying surface 23, as can be readily seen in FIG. 2 of the drawings in particular, and the open ends of the legs of the two slides 21 and 22 point toward one another. The upper legs of the U's of slides 21 and 22 are provided with recesses 25, the lower legs with recesses 26, so that upper carrying tabs 27 and lower carrying tabs 28 positioned next to one another at regular intervals are created (FIGS. 1 and 4).
The recesses are so devised, however, that the lower carrying tabs are correlated with gaps or recesses above and vice versa (FIG. 1). When the slide tate units are in starting position the upper carrying tabs 27 are located in each case under guides 29, formed in each case by a pair of blocks 30, 31. Other pairs of blocks 32, 33 create lower guides 34. The lower carrying tabs 28, because of the staggered arrangement vis-a-vis the upper carrying tabs 27, are situated underneath their blocks 32 and 33.
When the cops are transferred from the bobbin container 2 to the slide gate units 13 and 14, due to the design of the box slide (not shown) this comes about in such a way that one end of a cop 3 rests on each of the upper carrying tabs 27, each end lying between neighboring blocks 30 and 31. The vertical distance between the planes defined by the upper carrying tabs 27 on the one hand and the lower carrying tabs 28 on the other hand is approximately equal to or a little larger than the diameter of the ends of the bobbin or the thicker end of the bobbin. Now if the slides 21 and 22 are moved, in the direction indicated by the arrow 35, for example, and in synchrony, the upper carrying tabs 27 open the lower ends of the guides 29, so that the cops 3 lying on them can fall down. Meanwhile, however, the lower carrying tabs 28 are also moved to the lower end of their guides 34, so that the cops are now each held between blocks 32 and 33 and on tabs 28. Not until the slides 21 and 22 are synchronously moved back in the counter-direction to arrow 35 are the lower ends of the guides 34 opened so that the cops can fall down once again. With the exception of the outer left cop shown in FIG. 1 and the outer right cop (not shown) all the others fall onto the corresponding carrying surface 23 of the conveying elements 24 of the two cross-conveyors 11 and 12. The conveying elements 24 have crossridges 36 or the like projecting, outwardly distributed along the circumference, particularly at regular intervals. Between any two such crossridges falls a cop. This means that the conveyor elements 24 must be in a precisely predetermined resting position when the slides 21 and 22 are activated. A symbolically depicted molding 37 or the like separates the empty space above the conveying element 24 from the space above the righting chute 10. The cop that is on the outer edge in each case can fall directly onto the righting chute past the delivery end 18 of the cross-conveyor 11 or 12. Not until this cop has been delivered to a bobbin receptacle 6 will the corresponding cross-conveyor 11 or 12 be driven forward by one segment in the direction of arrow 16 so that the next cop can fall onto the righting chute.
As mentioned earlier, the device is designed as a double device which is symmetrical around the vertical plane 1. For this reason in the embodiment used as an example the slide gate units 13 and 14 are divided into two half slide gate units lying to the left and right of the vertical plane 1. As a result, each slide gate half or each pair of slide gate halves can be operated on its own, so that the cops in the left slide gate half-units can be transferred to their cross-conveyor 11 independently of those in the right slide gate half-units, and vice versa. The particular point of this construction lies in the fact that this device, as mentioned earlier, travels along the spooling frame first, for example, from the left end of the frame to the right and then travels back again from right to left. In one "travelling direction," cops are conveyed down the left righting chute 10, for example, and in the other direction down the right righting chute (not shown). This makes possible an ingenious and comparatively simple positioning of the device with respect to the various bobbin receptacles 6, regardless of the direction of travel. Furthermore, it opens up the possibility of feeding the spooling frame with one kind of cop via one cross-conveyor 11 and another, different kind of cop via the second cross-conveyor 12. The types of cops may differ in their length and diameter and in the yarn. For this reason, it is particularly helpful to enable the blocks 30 through 33 to change in width 38 in a manner not shown in detail, resulting, of course, in a widening or narrowing of the guides 29 and 34.
The intermediate space 39 between each cross-conveyor 11 or 12 and the halves of the slide gate units 13 and 14 above it can be monitored by means of a corresponding monitoring device 40, 41, particularly an optical device consisting of a light source and a reflector. A second monitoring device 42, 43, again particularly an optical device, serves to monitor the righting chute 10. These monitoring devices check for the presence of cops. If none of the monitoring devices detects a cop, the drive for the corresponding pair of slides 21, 22 or slide halves is released or activated. Furthermore, the two slides or slide halves of the two slide gate units 13, 14 or slide gate unit halves are coupled in terms of movement or are synchronously drivable.
Within the field of motion of the cop 3 leaving the delivery end 18 of the cross-conveyor 11 or 12 and falling onto the righting chute 10, or to speak more precisely, within the field of motion of the front end 44 of the cop as it falls down the chute, is a damping lever 45 (FIG. 1). It is a double-armed lever, preferably with an angular shape, that is tiltable about an axis 46. Its free end extending over the chute constitutes an impact member 47, and on its other arm, the right arm of the lever in FIG. 1, is an adjusting weight 48 that can be moved along the length of the arm. The center-of-gravity lever can be adjusted to different cop weights by, for example, screwing the weight up or down on its threaded rod that is fixed to lever 45. The impact member 47 brakes the cop end 44 somewhat so that the cop does not hit the righting chute 10 as hard.
In the vicinity of the delivery end 15 of the righting chute 10 is located a controllable stop lever 49. It can be rotated around an axis 52 in the direction of the double arrow 51 with the aid of an electromagnet, in particular a rotary magnet 50. A lever 53 is non-rotatably connected with the axis of rotation 55 of the rotary magnet 50. Via a joint 56 the lever 53 is articulated with another lever 54, the two together forming a toggle joint. The lever 54 is adjustable lengthwise. The lever 54 has been made lengthwise-adjustable, so that the pivot of the knee joint consisting of levers 53 and 54, namely, the pivots 55, 56 and 57, can be brought out into an extended position lying along the same line (see FIG. 2). Thus, the support 59 may be positioned in the ideal position for engaging the cop end. In its starting position, in other words, in the rest position of the magnet, the toggle joint is stretched out, i.e. the joint points 55, 56 and 57 lie in a straight line. This results in thorough breaking of the fall. If the magnet rotates, for example, in the direction of the arrow 58, it results in the stop lever 49 turning in the same direction of rotation. Its supporting end 59, which extends into the chute, then releases the front end 44 of the cop lying on it, so that the cop 3 can drop down into the approximately aligned bobbin receptacle 6. The stop lever 49 is made of a shock-absorbing material, in particular out of a plastic with sufficient elasticity, but with strength and low wear.
A controllable ejection lever 60 can be applied to the upper end 61 of the cop 3 supported on the stop lever 49. It is not brought into operating position until the lower end 44 of the cop rests on the supporting end 59 of the stop lever. The ejection lever 60 is pivoted in synchrony with the stop lever 49 in the same rotational direction. It supports and speeds up the process of sliding the cop 3 out of the righting chute 10. The axis of rotation of the ejection lever 60 is designated 62.
In the forward direction of the cop 3 sliding down the righting chute 10, there projects into the field of motion of the cop a braking element 63 preferably in the shape of a plate that can be deflected outwardly. The end 64 of element 63 that extends toward the chute 10 is designed as a centering element for the oncoming cop. It has a cut-out in the shape of an arc, triangle, trapezoid or the like.
A geared motor 65 drives a first toothed belt disc 66, which turns a second toothed belt disc 68 via a toothed belt 67. The second toothed belt disc 68 is seated on the drive shaft 69 for the corresponding halves of the slide gate units 13 and 14. The slide gate unit halves are driven by means of two eccentrics 70 and 71 also non-rotatably seated on the drive shaft 69. They engage in corresponding slots 87 of the slide gate unit halves. By this means the slide gate unit halves can be slid forward and back perpendicular to the projection plane of FIG. 3 without a reversal of rotation direction on the part of the geared motor 65. To guide the halves of the slide gate units 13 and 14 rollers or sliding pieces 72 and 73 are provided for a guide plate 74 for each.
An internal wall 75 positioned by what in FIG. 3 is the left end of the drive shaft 69, is adjustable and lockable in the direction of the double arrow 76. If starting from the position shown in FIG. 3 it is moved to the left. This has the effect of also moving the two havles of the slide gate unit 13 in the same direction. This increases the distance between the corresponding upper and lower supports and those opposite them, so that longer cops can now be supported. For this purpose, however, it is necessary for the drive shaft 69 to be able to pull out like a telescope. This is accomplished by a many-sided, specifically a four-sided shape 77 on the short left piece in FIG. 3 of the drive shaft 69 that engages positively in a recess 88 in the left end of the long right section of the drive shaft 69. The drive shaft 69 performs a 360° turn or two 180° turns following quickly upon one another. During the first 180° turn the upper guides 29 are opened and the lower guides closed, while during the second 180° turn the slide gate units or the halves thereof are pushed back into their starting position. The full or the two half rotations are accomplished with the aid of a trip cam 78 seated on the drive shaft 69, which works in conjunction with a stationary switch 79. The speed of motion of the slides can be adjusted to the size and weight of the cops by means of corresponding changes in the rpm of the first toothed belt disc 66.
The drive for each conveyor element of the cross-conveyor 11 or 12 is also accomplished by means of a geared motor 80 for each. Its drive shaft bears a toothed belt disc 81, which transmits the torque via a toothed belt 82 to another toothed belt disc 83. If necessary, a clutch 84 can also be interposed between the drive shaft of the motor and the first toothed belt disc 81. The second toothed belt disc 83 is coaxially connected with a front reversing roller 85 or the like for the conveyor element 24. A rear reversing roller or the like is labelled 86.
While specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | A device for transferring bobbins of yarn from a bobbin container to a bobbin receptacle on a spooling frame where the yarn is "refined" by cutting out bad spots, has slide gate units (13, 14) that are divided into slide gate unit halves. On the basis of a control system that comprises in particular an optical monitoring device (40, 41, and 42, 43), a given row of bobbins are transferred by a box slide from the bobbin container to the slide gate units (13, 14) or sliding gate unit halves. In two steps they fall from there onto a pair of cross-conveyors (11, 12) that operate in opposite directions. Each cross-conveyor is associated with a righting chute (10). A bobbin that is on the outside by-passes the cross-conveyor and falls directly onto the righting chute, while the others are transferred, at intervals, to the righting chute, as it is emptied. With the aid of a controllable supporting end (59) at the lower end of the chute, the bobbin is transferred at the scheduled time, to the bobbin receptacle (6) of one of a number of bobbin holders (4) on the spooling frame (5). | 1 |
[0001] A variety of documents is cited in this specification. The disclosure content of these prior art documents, including manufactorer's manuals, is herewith incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] New targets have been identified by comparative and statistical analysis of healthy and diseased patients, in particular by analyzing tissues and/or blood derived plasma from said patients. Usually, the comparative analysis can be done on different levels, such as on DNA-, RNA-, protein- and post translational levels. One commonly used technique is based on differential gene expression analysis. Briefly, mRNA derived from both, diseased and healthy cells is labeled and subsequently hybridised to a gene chip and quantified. Up- or downregulation of different mRNAs, as derived from the quantification signals, reveals potential new targets. Another approach well known in the prior art is based on the identification and comparison of DNA methylation patterns of DNA molecules derived from healthy and diseased patients.
[0003] It is to be noted in the above context, however, that neither the DNA modification (i.e. the DNA methylation pattern) nor the differential gene expression analysis (i.e. the level of mRNA expressed in a cell) necessarily reflects whether a specific protein encoded by the corresponding DNA or the corresponding mRNA is indeed expressed. Therefore, identification of differential expression levels, i.e. quantitative and also qualitative analysis of protein expression patterns of healthy as compared to diseased cells, remains challenging.
[0004] A method for identification of differential protein expression levels is based on differential two-dimensional gel analysis of said proteins with subsequent analysis via mass spectrometry, a technique well known to the person skilled in the art. Additionally, methods based on protein fractionation, such as, to mention but a few, techniques based on the use of protein chips, HPLC- and FPLC related techniques which are all known to a person skilled in the art.
[0005] Techniques of phage display offer, for example, the possibility to deplete a large library, e.g., an expression library of binding members, on samples, such as tissues or cells that are, for example, derived from a healthy donor, and use the residual population of the library on samples, such as tissues or cells, that are derived, for example, from a diseased donor. Binding members which have been traced by depletion analysis, i.e. which bind to (poly)peptide targets or counterparts of diseased tissues/cells but not to healthy tissues/cells are usually considered to bind to a target which is uniquely (or at least much higher) expressed on the target cells (e.g. the diseased cell). Subsequently, binding member/(poly)peptide target complexes can be identified by, e.g., mass spectrometry or methods for protein analysis well known to the person skilled in the art.
[0006] Of particular interest are binding members that internalize upon binding of their target. A person skilled in the art is aware that said binding members can, e.g., then be fused to any substance or any small molecule that might be toxic for the cell thus triggering the killing of the, preferably diseased, cell expressing said target(s), which cell preferably is diseased. As also known in the art, once a target of interest that internalizes has been identified as, e.g., a diseased or cancerous cell, it is then possible to determine further binding members with, e.g., higher affinity to the target and/or higher potential for triggering internalization of said target. Said improved binding members can then be considered, for example, as drugs for treating, e.g., diseased cells expressing said target(s).
[0007] To efficiently determine potential targets that have internalized into the cell upon binding of their respective binding member, it would be desirable to separate internalized complexes from non internalized complexes. However, in the prior art, said separation has not been achieved in a qualitative and quantitative satisfying manner thus confronting the skilled artisan with time consuming and complex techniques for determining binding members and targets that internalize.
[0008] There is therefore a continuous need to further develop and also ameliorate methods and processes that allow for efficient separation between internalized and non-internalized complexes.
BRIEF DESCRIPTION OF THE FIGURES
[0009] FIG. 1 shows efficiency of target internalization upon Fab binding.
[0010] Percent (%)-internalization was calculated from the ratio of extracellular signal on cell surface at 4° C. vs. 37° C.; recovery of fluorescence was measured by the ratio of extracellular plus intracellular staining at 4° C. vs. 37° C., showing that no or only few phage particles were lost during the internalization process, the saporin treatment and/or the staining. Fab A showed an 80% internalization, Fab B only internalized with 20%, and Fab C showed no binding at all.
[0011] FIG. 2 shows efficiency of phage target complex internalization and depletion of surface bound phage by DDT.
[0012] Internalization of phages displaying via a disulfide bond Fab A against an antigen that predominantly internalizes versus phages displaying via a disulfide bond a Fab B against an antigen that does not predominantly internalize is shown.
[0013] Percent (%)-internalization was calculated from the ratio of extracellular signal on cell surface at 4° C. vs. 37° C.; recovery of fluorescence was measured by the ratio of extracellular plus intracellular staining at 4° C. vs. 37° C.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention relates, in one aspect, to a method for recovering a nucleic acid molecule encoding a binding member of a complex internalized in a cell, comprising the following steps of (a) contacting a cell with a diverse collection of bacteriophage particles, wherein each or substantially all of said bacteriophage particles displays a binding member on its surface, wherein said binding member is displayed as a non-fusion (poly)peptide with a phage coat protein of said bacteriophage particle and wherein each or substantially all of said bacteriophage particles comprises a nucleic acid molecule encoding the displayed binding member, (b) allowing for binding of the binding member displayed on the bacteriophage particle to its target, thereby allowing for the formation of at least one complex, each of said complexes comprising a bacteriophage particle with its displayed binding member and its target, (c) culturing the cell under conditions that allow internalization of at least one of said complexes into the cell, (d) eluting the nucleic acid molecules encoding a binding member that are not internalized under conditions that substantially no cell lysis occurs, (e) lysing the cell comprising the internalized complexes, and (f) recovering from the lysed cell the nucleic acid molecule encoding a binding member derived from at least one of the internalized complexes.
[0015] The term “cell” refers to any eukaryotic or prokaryotic cell. Preferred in connection with the present invention are mammalian cells. Mammalian cells may comprise healthy and also diseased cells.
[0016] In the context of the present invention, the term “diverse collection” refers to a collection of at least two particles or molecules which differ in at least part of their compositions, properties, and/or sequences.
[0017] The term “a diverse collection of bacteriophage particles” as used in connection with the present invention refers to a plurality of bacteriophage particles. Each or substantially all members of such a plurality display a distinct binding member. Methods for the generation of diverse collections of bacteriophage particles are well-known to one of ordinary skill in the art.
[0018] The term “bacteriophage” as used in connection with the present invention is to be construed in its broadest sense. In the context of the present invention, the term “bacteriophage” therefore relates to any bacterial virus that forms a package having a protein coat containing nucleic acid required for the replication of the phage. The nucleic acid may be DNA or RNA, either double or single stranded, linear or circular. Bacteriophage such as phage lambda or filamentous phage (such as M13, fd, or fl) are well known to the artisan of ordinary skill in the art.
[0019] Preferred in the context of the present invention is a filamentous bacteriophage, such as, for example, M13 bacteriophage. More preferred is the filamentous bacteriophage VCSM 13.
[0020] In the context of the present invention, the term “bacteriophage particles” refers to the particles according to the present invention, i.e. to particles displaying a (poly)peptide/protein.
[0021] In the above context, it is to be considered that each or substantially all members of the diverse collection of bacteriophage particles display a binding member, wherein each binding member preferably differs in at least one amino acid position of their sequence.
[0022] The term “binding member” in accordance with the present invention refers to any (poly)peptide that can bind to a specific counterpart or target, thereby forming a complex. Said term, in connection with the present invention, is construed to comprise, inter alia, any scaffold known to a skilled artisan. A “scaffold” in connection with the present invention refers to any collection of (poly)peptides having a common framework and at least one variable region. Scaffolds known to the skilled artisan are, for example, fibronectin based scaffolds or ankyrin repeat protein based scaffolds. The term “(poly)peptide” as used herein describes a group of molecules which comprise the group of peptides, as well as the group of polypeptides. The group of peptides is consisting of molecules with up to 30 amino acids, the group of polypeptides or proteins is consisting of molecules with more than 30 amino acids. The term “(poly)peptide” in connection with the present invention is construed to also comprise an antibody or antibody fragment or derivative thereof. Said antibody is to be construed to comprise any immunoglobulin known to the skilled artisan. An “immunoglobulin” (Ig) is protein belonging to the class IgG, IgM, IgE, IgA, or IgD (or any subclass thereof), and includes all conventionally known antibodies and functional fragments thereof. A “functional fragment” of an antibody/immunoglobulin hereby is defined as a fragment of an antibody/immunoglobulin (e.g., a variable region of an IgG) that retains the antigen-binding region. The term “antibody fragment or derivative thereof” relates to single chain antibodies, or fragments thereof, synthetic antibodies, antibody fragments, such as Fab, a F(ab2)′, Fv or scFv fragments, single domain antibodies etc., or a chemically modified derivative of any of these. Antibodies to be employed in accordance with the invention or their corresponding immunoglobulin chain(s) can be further modified outside the motifs using conventional techniques known in the art, for example, by using amino acid deletion(s), insertion(s), substitution(s), addition(s), and/or recombination(s) and/or any other modification(s) (e.g. posttranslational and chemical modifications, such as glycosylation and phosphorylation) known in the art either alone or in combination. Methods for introducing such modifications in the DNA sequence underlying the amino acid sequence of an immunoglobulin chain are well known to the person skilled in the art; see, e.g., Sambrook et al.; Molecular Cloning: A Laboratory Manual; Cold Spring Harbor Laboratory Press, 2nd edition 1989 and 3rd edition 2001.
[0023] Fragments or derivatives of the recited antibody molecules define (poly)peptides which are parts of the above antibody molecules and/or which are modified by chemical/biochemical or molecular biological methods. The same applies, mutatis mutandis, to any scaffold. Corresponding methods are known in the art and described inter alia in laboratory manuals (see Sambrook et al., loc cit.; Gerhardt et al.; Methods for General and Molecular Bacteriology; ASM Press, 1994; Lefkovits; Immunology Methods Manual: The Comprehensive Sourcebook of Techniques; Academic Press, 1997; Golemis; Protein-Protein Interactions: A Molecular Cloning Manual; Cold Spring Harbor Laboratory Press, 2002).
[0024] The term “is displayed as a non-fusion (poly)peptide” in the context of the present invention refers to any (poly)peptide that is not displayed via any of the conventional fusion techniques known to a person skilled in the art. Conventional display can be achieved, for example, by genetic fusion wherein a fusion protein results as an expression product from the fusion of preferably two genes. A skilled artisan is aware that said fusion protein in the prior art sometimes is referred to as a hybrid or a chimeric protein, which is created by the expression of a hybrid gene, made by genetic engineering and wherein preferably two separate gene sequences are combined.
[0025] The term “phage coat protein” in connection with the present invention is considered to comprise not only phage coat proteins derived from any phage well known to the skilled artisan, but also fragments derived therefrom, wherein said fragments are capable of being incorporated into the protein coat of the bacteriophage particle.
[0026] The term “target” as used in connection with the present invention refers to (i) any (poly)peptide expressed on a cell that can bind a binding member or (ii) any molecule capable of being internalized into a cell, and which can bind a binding member. Preferred are any cell surface receptors, more preferred receptor tyrosine kinases. The targets comprise any target not known to a skilled artisan and yet to be identified or might be known per se but not in the context of their capacity of internalization. A cell expressing at least one of the potential targets is also referred to in connection with the present invention as a “target cell”.
[0027] The term “allowing internalization of at least one of said complexes into the cell” refers to any technique well known to a skilled artisan to trigger internalization of the complex into the cell. Preferred are techniques relying on temperature shifts, such as, for example, increasing the temperature from 4° C. to 37° C.
[0028] The term “substantially no cell lysis” in the term “eluting the nucleic acid molecules encoding a binding member that are not internalized under conditions that substantially no cell lysis occurs” as used in connection with the present invention is to be construed that not more than approximately 50%, preferably approximately 40%, more preferably approximately 30%, more preferably approximately 20%, preferably not more than approximately 10%, more preferably not more than approximately 5%, even more preferably not more than approximately 1% of the cells are lysed and most preferably none of the cells are lysed.
[0029] The term “lysing the cell comprising the internalized complex” as used in connection with the present invention comprises any techniques for lysing cells known to a skilled artisan. As regards mammalian cells, lysis due to the presence of triethylamin is preferred.
[0030] As has been outlined above and in other terms, the invention solves the recited technical problem by providing a method that reliably and efficiently allows the skilled artisan to distinguish between internalized and non internalized complexes. With the display techniques based on fusion proteins, a separation of internalized and non-internalized complexes can usually only be achieved by applying rather harsh elution steps with appropriate buffers, such as by using pH- or salt gradients, in order to also deplete the high affinity binding members. Unpredictable cell lysis events result, leading to a mixture of internalized and non-internalized complexes complicating or even preventing any further analysis. The present invention overcomes the above situation, by transferring the advantages of non-fusion display systems, such as, for example, mild elution conditions and independence of the specific affinity between binding member and target, to the field of internalizing complexes.
[0031] In a preferred embodiment, a method of the present invention further comprises the step of determining the sequence of the target of the internalized complex. The skilled artisan is aware of techniques for determining the sequence of targets of internalized complexes. Preferably, techniques for determining the amino acid sequence of a (poly)peptide target are contemplated. Reference is also made to the embodiments further below.
[0032] In another preferred embodiment of the method of the present invention, said display as a non-fusion (poly)peptide is characterized by a non-peptide bond between the phage coat protein and the binding member.
[0033] In a more preferred embodiment of the method of the present invention, said non-peptide bond is a disulfide bond.
[0034] In a most preferred embodiment of the present invention, said disulfide bond is generated between a first cysteine residue comprised in said phage coat protein and a second cysteine residue comprised in said binding member.
[0035] In another most preferred embodiment of the method of the present invention, said elution of said nucleic acid molecules encoding a binding member that are not internalized is carried out under reducing conditions such that said disulfide bond is cleaved.
[0036] This and the previous embodiment refer to a situation wherein the disulfide bond is responsible for the attachment. Details of the above system are disclosed in the patent application WO 01/05950, the contents of which is expressly incorporated herein by reference.
[0037] In a preferred embodiment of the method of the present invention, said recovery from the lysed cell of said nucleic acid molecule encoding the binding member is achieved by PCR. In the context of this preferred embodiment, PCR primers can, for example, be used which are capable of amplifying a binding member of interest. Techniques based on specific primers for amplification of nucleic acid molecules by polymerase chain reaction (PCR) are well known to the skilled artisan.
[0038] In another embodiment of the method of the present invention said step of determining the sequence of the target in the internalized complex is achieved by mass spectrometry.
[0039] The person skilled in the art is aware of techniques for recovering from lysed cells nucleic acid molecules and of techniques for determining the sequence of a (poly)peptide in a complex.
[0040] The present invention also relates to a target and/or a binding member obtainable by the method of the present invention.
[0041] Finally, the present invention relates to a method for delivering a toxic substance into a cell comprising the steps of (a) obtaining a (poly)peptide encoded by the recovered nucleic acid molecule of claim 1 , (b) combining said toxic substance with said (poly)peptide encoded by the recovered nucleic acid of claim 1 , and (c) administering to a cell the toxic substance resulting from step (b), thereby triggering internalization of said toxic substance into the cell.
[0042] As mentioned above and in other words, the present invention can be used for identifying binding members and/or targets which have the potential to internalize into cells. Preferably, as explained above, said binding members and/or targets can be applied in connection, for example, with the killing of diseased cells, such as cancerous cells. It is to be noted, however, that any application whatsoever known to the skilled artisan and based on the identification of binding members and/or targets capable of internalizing into a cell, is construed to be comprised in the scope of the present invention.
[0043] The following examples are provided to illustrate the present invention and are not to be construed to be limiting thereof.
EXAMPLES
Example 1
[0044] Experimental procedure for use of the present invention's method to identify internalization targets.
Preparation of Target and Control Cells
[0045] 1. Wash the target cells (transfected or antigen positive) and control cells (mock-transfected or antigen negative) 3× with 5% FCS 1 /PBS 2 or with PBS if cells will be fixed (see 2.2.3). TBS or HBS should be used if Ca2+ must be added to all buffers (see section 1.3; calcium precipitates in the presence of phosphate as calcium-phosphate). 1 FCS: Fetal bovine serum: 0.1 μm sterile filtered, mycoplasma tested. PAN BiotechGmbH, Aidenbach, #3302-P971610. (Or mycoplasma tested FCS from any other supplier.) 2 PBS Dulbecco's: w/o calcium and magnesium and w/o sodium bicarbonate, Gibco BRL Life Technologies, #14190-094.
2. Count target cells and adjust to 5×106−1×107 cells in 1 ml 5% FCS/PBS in a 2 ml micro-centrifuge tube for each selection
3. Keep all subsequent steps at the appropriate temperature of 4° C. on ice for 2 h on an over head rotator at 4° C. for blocking.
4. Adjust phage titer of the combined library phage to 1-2×1013 phage in 1 ml 5% FCS/PBS (+suppl.). Incubate for 2 h at 4° C. for on an over-head rotator to block phage.
Selection on Target Cells
[0046] 5. The blocked target cells are centrifuged at 2000 rpm for 2 min and resuspended in 0.5-1 ml pre-adsorbed phage-solution.
6. Incubate for 2 h at 4° C. on a rocker.
7. Spin cells at 2000 rpm for 2 min.
8. Carefully pipette off the supernatant and discard.
9. First Wash: carefully resuspend cell pellet in 1 ml 5% FCS/PBS (+suppl.) using a pipette.
10. Incubate for 5 min at 4° C.
[0047] 11. Spin cells at 2000 rpm for 2 min.
12. Carefully pipette off the supernatant and discard.
13. Second Wash: carefully resuspend cell pellet in 1 ml 5% FCS/PBS (+suppl.) using a pipette.
14. Incubate for 5 min at 4° C. for live cells or at 20° C. for fixed cells on a rocker.
15. Spin cells at 2000 rpm for 2 min.
16. Carefully pipette off the supernatant and discard.
17. Third Wash: carefully resuspend cell pellet in 1 ml 5% FCS/PBS (+suppl.) using a pipette. Transfer cells to a new sterile 2 ml tube that has been blocked with 5% FCS/PBS 3 . 3 This step helps to avoid again enrichment of phage un-specifically bound to the selection tube.
18. Incubate for 5 min at 4° C. for live cells or at 20° C. for fixed cells on a rocker.
19. Spin cells at 2000 rpm for 2 min.
20. Carefully pipette off the supernatant and discard.
Internalization of Phage:
[0048] 21. Carefully resuspend cell pellet in 1 ml 5% FCS/PBS (+suppl.) using a pipette.
22. Increase temperature to 37° C. and incubate for 30 min
Depletion of not Internalized Phage
[0049] 23. Add 300 μl 20 mM DTT in 10 mM Tris/HCl, pH8.0 4 to the cells and incubate for 10 min at RT 5 , spin at 2000 rpm for 2 min, discard supernatant 4 20 mM DTT in 10 mM Tris/HCl, pH 8.0: the DTT solution should always be stored at −20° C. Avoid multiple freezing and thawing of the solution. 5 Instead of DTT elution, which is recommended for the HuCAL GOLD® library, conventional elution methods can also be used (e.g., see Krebs et al., 2001)
24. Fourth Wash: carefully resuspend cell pellet in 1 ml 5% FCS/PBS (+suppl.) using a pipette.
25. Incubate for 5 min at 4° C.
[0050] 26. Spin cells at 2000 rpm for 2 min.
27. Carefully pipette off the supernatant and discard.
28. Fifth Wash: carefully resuspend cell pellet in 1 ml 5% FCS/PBS (+suppl.) using a pipette.
29. Incubate for 5 min at 4° C. for live cells or at 20° C. for fixed cells on a rocker.
30. Spin cells at 2000 rpm for 2 min.
31. Carefully pipette off the supernatant and discard.
Recovering of Internalized Phase
[0051] 32. Add 500 μl 100 mM triethylamine (140 μl TEA in 10 ml PBS) and incubate for 10 min at RT (cells tend to lyse immediately). Add 400 μl 1M Tris pH 7.0 for neutralization. Check pH after neutralization with pH-indicator stick.
33. Use eluate for infection of TG1 (DWCP)
34. Identify and express Fab expressing clones by standard procedures.
Example 2
[0052] Antigen A, B and C were tested for prevalence on cell and Fab A, B, C for internalization properties.
Materials and Methods:
Fabs Tested:
[0000]
Fab_C_FH (Lysozyme binder, negative control)
Fab_B_FS (ICAM binder, non internalizing control)
Fab_A_FH (antigen A, internalizing)
Fabs tested at 1 μg/ml
Cells:
[0000]
NCI H226: lung carcinoma cells
1×10E5 cells/measurement
Other Material:
[0000]
10% Saponin: 1 g Saponin was dissolved in 10 ml PBS, 0.5% Saponin/PBS, stored at 4 C
4% PFA: stocksolution 16% was diluted 1:4 in PBS. Stocksolution: 16% w/v Alpha Aesar, Lot E10S015
FACSbuffer (FB): PBS/3% FCS, stored at 4 C
Goat anti human IgG (H+L)-PE, Jackson Dianova, 109-116-088, diluted 1:200 in FACS buffer (PBS/3% FCS)
Procedure:
[0000]
1. 100 μl Fab (1 μg/ml) were added to a pellet of 2.5*10 6 NCI H226 cells in FACSbuffer and incubated for one hour on ice. The cells were washed 2 times using 200 μl FACSbuffer, centrifuged (2000 rpm) and resuspended in 200 μl medium.
2. 100 μl were transferred to a 96 well plate and incubated for 1 h at 4° C. and further 10 min on ice.
3. The cells were washed 2 times 200 μl FACSbuffer; 200 rpm
4. Resuspended in 200 μl FACSbuffer, split in 2 times 100 μl and centrifuged 2 min 1200 rpm
For Non Internalizing Conditions (4° C.):
For Extracellular Staining:
[0000]
5. Cells were resuspended with 100 μl Goat anti human IgG-PE and incubated for 1 hour at 4° C. and washed two times with 200 μl FACSbuffer; 200 rpm
6. Resuspended in 100 μl FACSbuffer
7. FACS was then measured on BD FACSARRAY FSC 50; SSC; 280; Yellow 420
For Intracellular Staining:
[0000]
8. Cells from step (4) were resuspended in 100 μl 4% PFA, 4° C. 30 min
9. Cells were washed 2 times with 200 μl FACSbuffer; 2000 rpm
10. Cells were resuspended in 0.5% Saporin, 10 min RT
11. 100 μl anti human IgG-PE were added and incubated for 1 h at RT
12. Cells were washed 2 times with 0.5% Saporin, 200 rpm
13. Resuspended in 100 μl FACSbuffer
14. FACS was then measured on BD FACSARRAY FSC 50; SSC; 280; Yellow 420
For Internalizing Conditions (37° C.):
For Extracellular Staining:
[0000]
15. Cells from step (4) were resuspended with 100 μl Goat anti human IgG-PE and incubated for 1 hour at 37° C. and washed two times with 200 μl FACSbuffer; 200 rpm
16. Resuspended in 100 μl FACSbuffer
17. FACS was then measured on BD FACSARRAY FSC 50; SSC; 280; Yellow 420
For Intracellular Staining:
[0000]
18. Cells from step (4) were resuspended in 100 μl 4% PFA, 4° C. 30 min
19. Cells were washed 2 times with 200 μl FACSbuffer; 2000 rpm
20. Cells were resuspended in 0.5% Saporin, 10 min RT
21. 100 μl anti human IgG-PE were added and incubated for 1 h at RT
22. Cells were washed 2 times with 0.5% Saporin, 200 rpm
23. Resuspended in 100 μl FACSbuffer
24. FACS was then measured on BD FACSARRAY FSC 50; SSC; 280; Yellow 420
Results:
[0087] As shown in FIG. 1 , 80% of Fab target A were internalized as compared to only 20% of the Fab target B complex. The internalization process, cell permeabilization and staining did not influence the overall phage number.
Example 3
[0088] Enrichment of internalizing phages by DTT cleavage of extracellular bound phages
Materials and Methods:
Phages Tested:
[0089] Genes encoding Fab A, B, C (see Example 1) were subcloned in Cys-Display vector pMORPH23 and VCSM 13 derived phages were produced according to standard procedures.
Phage_Fab_C (Lysozyme binder, negative control) Phage_Fab_B_ (ICAM binder, non internalizing control) Phage_Fab_A_ (antigen A, internalizing) 1×10E10 phages each were used
Stripping:
[0000]
20 mM DTT in 10 nM Tris/HCl pH 8.0, Roche Cat# 1583786
Antibodies:
[0000]
Anti M13 mab: Amersham Biosciences, 27-9420-01, 1 mg/ml, to be diluted 1 μg/ml in FACS buffer FB (PBS/3% FCS)
Goat anti mouse IgG Fc gamma fragment specific-PE, Jackson Dianova, 115-116-071, R14, to be diluted 1:200 in FACS buffer (PBS/3% FCS)
Cells:
[0000]
NCI H226: lung carcinoma cells
1×10E5 cells/measurement
Other Material:
[0000]
10% Saponin: 1 g Saponin was dissolved in 10 ml PBS, 0.5% Saponin/PBS
4% PFA: stocksolution 16% was diluted 1:4 in PBS. Stocksolution: 16% w/v Alpha Aesar, Lot E10S015
FACSbuffer (FB): PBS/3% FCS
Goat anti mouse IgG Fc gamma fragment specific-PE, Jackson Dianova, 115-116-071, R14, to be diluted 1:200 in FACS buffer (PBS/3% FCS)
Procedure:
[0000]
1. 1×10E10 phages were added to a pellet of 5*10 4 NCI H226 cells in FACSbuffer and incubated for one hour at 4° C. The cells were washed 2 times using 400 μl FACSbuffer, centrifuged (2000 rpm) and resuspended in 600 μl medium.
For Non Internalizing Conditions (4° C.):
[0000]
2. 2×100 μl were transferred to a 96 well plate and incubated for 1 h at 4° C. and further 5 min on ice.
3. The cells were washed 2 times 200 μl FACSbuffer; 200 rpm
4. Resuspended in 200 μl FACSbuffer, and centrifuged 2 min 2000 rpm
5. One control aliquot was resuspended in 100 μl, the second one in 50 μl DDT
6. The cells were stored on ice for 5 min and washed 2 time using 200 μl FACSbuffer and 1200 rpm
7. The cells were resuspended in 50 μl anti-M13 antibody (5 μg/ml FACSbuffer)
8. The cells were incubated 45 min at 4° C.
9. The cells were washed two times 200 μl FACSbuffer
10. The cells were resuspended in 100 μl Goat anti mouse IgG Fc gamma fragment specific-PE (1:100)
11. The cells were washed 2 times with 200 μl FACSbuffer
12. FACS was measured on BD FACSARRAY FSC 10; SSC335; Yellow 330
For Internalizing Conditions (37° C.):
[0000]
13. 2×100 μl were transferred to a 96 well plate and incubated for 1 h at 37° C. and further 5 min on ice.
14. The cells were washed 2 times 200 μl FACSbuffer; 200 rpm
15. Resuspended in 200 μl FACSbuffer, and centrifuged 2 min 2000 rpm
16. One control aliquot was resuspended in 100 μl, the second one in 50 μl DDT
17. The cells were stored on ice for 5 min and washed 2 time using 200 μl FACSbuffer and 1200 rpm
18. The cells were resuspended in 50 μl anti-M13 antibody (5 μg/ml FACSbuffer)
19. The cells were incubated 45 min at 4° C.
20. The cells were washed two times 200 μl FACSbuffer
21. The cells were resuspended in 100 μl Goat anti mouse IgG Fc gamma fragment specific-PE (1:100)
22. The cells were washed 2 times with 200 μl FACSbuffer
23. FACS was measured on BD FACSARRAY FSC 10; SSC335; Yellow 330
Results:
[0126] Under the conditions of the experiment (with/without DTT, 4° C. or 37° C.) the cells stayed intact. As expected, cell binding of Phages bearing Fab C couldn't be detected.
[0127] As shown in FIG. 2 , approximatly 65% of phage A and 20% of phage B were internalized when increasing the temperature from 4° C. to 37° C.
[0128] Phages on the cell surface could be effciently stripped by 5 min treatment with 20 mM DTT at 4° C., without influencing cell integrity.
[0129] DTT addition upon internalization stripped surface bound phages while leaving internalized ones intact thus allowing an enrichment of phages binding to internalizing targets. | A target internalized within a cell (and a binding member that specifically binds thereto) can be identified in an efficient manner by segregating (or substantially segregating) genetic material encoding the binding member from genetic material encoding a binding member that binds to a target that is not internalized. This can be achieved by employing a display library of binding members having a genotype/phenotype linkage via a non-fusion protein format, whereby genetic material encoding non-in-ternalized targets can be segregated (or substantially segregated) without lysing the cells. Internalized genetic material subsequently can be isolated and amplified. | 2 |
BACKGROUND AND SUMMARY
[0001] The present invention relates to an auxiliary power unit (APU), methods of operating an APU and a vehicle comprising said APU and/or said method.
[0002] One way to provide electric power and heat to the truck driver's welfare when not driving the truck is to use the engine as a power source. This is often an inefficient way to produce electricity and heat both from fuel consumption and emission aspects, and will also be subject to legal restrictions in the near future. Typical engine effiencieny at idle is around 5-10%. One way which this is solved is with an auxiliary power unit (APU) consisting of a fuel processor for converting diesel to hydrogen and a fuel cell for converting hydrogen to water and electric power.
[0003] To lower the demand for oil, there are ongoing work for alternative fuels. One alternative fuel is dimethyl ether (DME). For these vehicles there will also be a need for an APU. A fuel processor for DME may be simpler in construction than a diesel fuel processor with lower working temperature and fewer gas cleaning steps. In EP01060535B1 a fuel cell able to be used with DME as feed is described. With this fuel cell the APU can be simplified to just a fuel cell, water recovery, cooling and fuel and air pumping to the fuel cell.
[0004] However, a problem with DME is its very low lubricating properties. Therefore there is a need to mix DME with a small amount of lubricant before sold as fuel. This lubricant may have very different properties for fuel processing and may eventually cause the DME fuel processor to make gases not suited for a fuel cell. Another problem with APU's is the need of water to the fuel processor and the fuel cell, this is solved by condensing water from the fuel cells off-gases see e.g., U.S. Pat. No. 7,036,466B2. The cooling for the water condensing could be arranged by blowing ambient air by a fan. However this cost energy for the fan and can also be inefficient and even impossible in some climate due to the low condensing temperature needed. Some solutions of the latter is described in U.S. Pat. No. 6,759,154 and DE10337607.
[0005] As explained above, there is a problem associated with DME mixed with lubricant for the functionality and/or properties for the fuel cell in an APU.
[0006] It is desirable to provide an APU in which the above mentioned problem with DME mixed with lubricants is at least reduced or eliminated.
[0007] In a first example embodiment an auxiliary power unit (APU) comprising a fuel processor and a fuel cell, said fuel processor is provided with steam, air and DME. Said APU further comprising an afterburner for combusting rest fuel from the fuel cell, wherein exhaust gases from said afterburner is used for heating a first heat exchanger. Said fuel processor is preparing the vehicle fuel to a fuel suitable for the fuel cell and said fuel processor is provided between said fuel reservoir and said fuel cell. The interpretation of preparing is meant to include for instance one or more of the following: transformations, distillations, any form of reactions, adsorptions, absorptions, change of state of aggregation, mixtures, solutions, etc.
[0008] In another example embodiment said first heat exchanger has at least one inlet and at least one outlet, said at least one inlet is provided with DME comprising a lubricant from a fuel tank. Said at least one outlet from said first heat exchanger is providing clean DME, and said lubricant is trapped in said first heat exchanger.
[0009] In still another example embodiment the APU further comprising a second heat exchanger, said second heat exchanger is connected to the exhaust gases from said after burner, said second heat exchanger further comprising at least one inlet and at least one outlet, said at least one inlet is connected to a condenser with condensed water from the fuel cell, said outlet is connected to said fuel processor for providing steam to said fuel processor.
[0010] In still another example embodiment said first heat exchanger and said second heat exchanger is the same unit.
[0011] In still another example embodiment said first heat exchanger is heated by gases from a water condenser.
[0012] In still another example embodiment said first heat exchanger has a DME fuel inlet and DME gas outlet and a lubricant outlet.
[0013] In still another example embodiment said first heat exchanger has a gas inlet and gas outlet and an outlet for condensed water.
[0014] In still another example embodiment said first heat exchanger is heated by cooling water from the fuel cell.
[0015] In still another example embodiment said first heat exchanger has a DME fuel inlet and DME gas outlet and a lubricant outlet.
[0016] In still another example embodiment said first heat exchanger has a cooling water inlet and cooling water outlet.
[0017] It is desirable to provide an auxiliary power unit process in which the above mentioned problem with DME mixed with lubricant is at least reduced or eliminated.
[0018] In a first example embodiment an auxiliary power unit process comprising the actions of providing air, steam and DME fuel to fuel processor unit, extracting at least hydrogen from said fuel processor unit, providing said hydrogen and air to a fuel cell, condensing water extracted from said fuel cell in a condenser, combusting rest fuel from the fuel cell in an after burner, separating a lubricant from a DME fuel before providing said DME fuel to the fuel processor unit.
[0019] In another example embodiment of the auxiliary power unit process, said separating of DME and lubricant is performed by using exhaust gases from said after burner in a first heat exchanger.
[0020] In still another example embodiment said first heat exchanger is heated by gases from a water condenser.
[0021] In still another example embodiment said first heat exchanger has a DME fuel inlet and DME gas outlet and a lubricant outlet.
[0022] In still another example embodiment said first heat exchanger has a gas inlet and gas outlet and an outlet for condensed water.
[0023] In still another example embodiment said first heat exchanger is heated by cooling water from the fuel cell.
[0024] In still another example embodiment said first heat exchanger has a DME fuel inlet and DME gas outlet and a lubricant outlet.
[0025] In still another example embodiment said first heat exchanger has a cooling water inlet and cooling water outlet.
[0026] In yet another example embodiment the auxiliary power unit process further comprising the action of providing steam to said fuel processor by heating said water from said condenser in a second heat exchanger heated by said exhaust gases from said after burner.
[0027] In still another example embodiment of the auxiliary power unit process said first heat exchanger for providing steam is the same heat exchanger as the second heat exchanger for separating the lubricant from the DME fuel.
[0028] The present invention also relates to a vehicle provided with an engine for traction power, an auxiliary power unit (APU) and a reservoir of fuel. Said fuel is used for running said engine and said APU. Said APU comprising a fuel processor and a fuel cell, wherein said fuel processor is provided between said fuel reservoir and said fuel cell. Said fuel is dimethyl ether (DME), wherein means is provided for separating said DME fuel from at least one lubricant included in said DME.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] With reference to the appended drawings below follows a more detailed description of embodiments of the invention cited as examples.
[0030] In the drawings:
[0031] FIG. 1 a shows a schematic view illustrating a first example embodiment of an APU according to the invention.
[0032] FIG. 1 b shows a schematic view illustrating a second example embodiment of an APU according to the invention.
DETAILED DESCRIPTION
[0033] In FIG. 1 a an APU 100 according to an example embodiment of the invention is schematically illustrated. The APU 100 comprises an optional air compressor 102 , a reformer 104 , a CO clean-up 108 , a fuel cell 122 , an afterburner 124 , a condenser 120 , a first heat exchanger 114 and a second heat exchanger 180 .
[0034] The first heat exchanger 114 may be used interchangeably with the second heat exchanger 180 in the following text and claims, i.e., they may be the same unit or may change position with each other in the embodiments as illustrated in the figures and the following text.
[0035] The reformer 104 may have different designs and properties. In a first embodiment said reformer 104 comprises a mix zone and a catalytic converter. The mix zone is arranged at an inlet side of said reformer and the catalytic converter is arranges at an outlet side of the catalytic converter, i.e., said mix zone is arranged prior to said catalytic converter in a direction of flow of gases introduced into the reformer 104 . Said first embodiment of the reformer 104 may be used when the gases to be reformed are not mixed before entering said reformer 104 . In a second embodiment said reformer. 104 is a catalytic converter without a mix zone. The second embodiment of the reformer 104 may be useful when the gases to be reformed are premixed before entering said reformer 104 . The catalytic converter in said reformer 104 may be made of ceramic or metal in the form of a monolithic structure. A catalytic material is attached onto said monolithic structure. Said catalytic material may for instance comprise different palladium-zinc alloy on AI2O3. Said catalytic converter may also be divided into different zones with different properties, i.e., different catalytic materials in different zones and/or different mixtures of two or more catalytic materials in different zones. A catalytic converter divided into zone as just described may be used to favour at least one reaction in a beginning or an end of the catalytic converter and/or to suppress at least a second reaction at the beginning or the end of the catalytic converter. Instead of using a monolithic structure as the bearer of the catalytic material pellets covered at least partially with catalytic material may be used. Said pellets may be in the form of solid bodies in any form for instance spherical or irregular. Said pellets may be made of ceramic material or a metal. Instead of using in the form of solid bodies, porous bodies may be used. Instead of covering the pellets made of non catalytic material at least partly with a catalytic material, said pellets may be made of a catalytic material.
[0036] Enclosing said pellets or monolithic structure and if present the mixing zone is a body made for instance of steel. Said body may be isolated. The reformer 104 may also be built as a heat exchanger. The temperature inside the reformer 104 may be between 250 C-700 C.
[0037] The reformer 104 has at least one inlet and at least one outlet. If present, the mixing zone is closest to said inlet and the catalytic converter is closes to the outlet. The reformer 104 is provided with different gases. The reformer 104 is a part of a process of reforming at least one gas into a suitable fuel for the fuel cell. According to an example embodiment of the present invention air, DME and steam are used as input gases into the reformer. In the example embodiment illustrated in FIG. 1 a, air is provided air a first inlet 172 , DME is provided at a second inlet 174 , and steam is provided at a third inlet 176 of said reformer 104 . In said reformer many different reactions are taking place. Some of the more important reactions are as follows:
[0000] DME+air: CH3OCH3+3/2 02=>2CO2+3H2 1)
[0000] DME+steam: CH3OCH3+3H20→2CO2+6H2 2)
[0000] DME+air: CH3OCH3+1/2O2=>2CO+3H2 3)
[0000] CO+steam: CO+H20<=>CO2+H2 4)
[0000] DME+steam: CH3OCH3 H20=>>2CH3OH 5)
[0000] Methanol+air: CH3OH+V2 02=>CO2+2H2 6)
[0000] Methanol+steam: CH3OH+H2O=>CO2+3H2 7)
[0000] Methanol+air: CH3OH+O2→CO+2H20 8)
[0038] From the list of reactions above, desired reactions are reaction 1 and 2. The other equations (3-8)+the equations not mentioned are so called secondary reactions which may be suppressed as much as possible. Reaction number 4 is a balance equation which is moved to the right at higher temperatures.
[0039] From the outlet 178 of the reformer 104 comes inter alia N2, CO, H2, H20 CH4 and traces of other material and/or contaminations from inter alia the air provided at the input of the reformer 104 .
[0040] In the illustrated embodiment in FIG. 1 a, air is provided to the first inlet 172 of the reformer via a first pipe 128 , DME is provided to the second inlet 174 of the reformer via a second pipe 126 , and steam is provided to the third inlet 176 of the reformer via a third pipe 130 . Air may be provided into the reformer with an overpressure created by an optional air compressor 102 . In an alternative embodiment said reformer 104 only comprises one inlet for providing the different gases, which may be blended or not depending on the design of the reformer 104 . If the gases are not blended, the above mentioned mixing chamber is in the reformer 104 .
[0041] The outlet 178 of the reformer 104 is coupled to a first inlet 180 of the CO clean-up device 108 via a fourth pipe 160 . In said fourth pipe 160 , N2, CO, H2, H20 and CH4 from the reformer 104 are transferred to the CO clean-up device 108 . Also provided to the CO clean-up device 108 is air to a second inlet 182 of said CO clean up 108 via pipe 128 , which may or may not be provided with overpressure depending on the presence of the compressor 102 . The CO clean-up device 108 may be built similarly as the reformer 104 with a slight difference in the material chosen for the catalytic converter. In the CO clean-up device 108 said catalytic converter material may be platinum-based. The temperature in the CO clean-up device is between 150 C- 180 C. In one embodiment said CO clean-up device is built as a heat exchanger. Between the reformer 104 and the CO clean-up device 108 a heat exchanger may be provided.
[0042] A desired reaction taking place in the CO clean-up device 108 is:
[0000] CO+1/2O2=>CO2 9)
[0043] An optional reaction can be H2+1/2O2=>H20 which will consume the hydrogen and is undesired and will lower the total efficiency for the system
[0044] As the name of the device may suggest said CO clean-up device is used for transforming harmful CO which is present in the gases coming from the reformer 104 into less harmful CO2.
[0045] An output 184 of the CO clean-up device 108 is connected to a first inlet 186 of the fuel cell 122 via a fifth pipe 150 . Air is also provided to a second inlet 188 of the fuel cell 122 via the first pipe 128 . Depending on the presence of the air compressor 102 said air is provided to the fuel cell 122 with overpressure or not. Gases provided to the fuel cell 122 is air and the gases produced in the reformer 1.04 minus all or part of the CO content which is transformed into CO2 in the CO clean-up device 108 . The reaction taking place in the fuel cell 122 is:
[0000] H2+1/2O2→H20. 10)
[0046] Said reaction is taking place on electrodes, where electrons are moving in wires and hydrogen ions are moving through an electrolyte membrane which separates the hydrogen gas from the air.
[0047] The fuel cell 122 has a first cooling pipe 154 and a second cooling pipe 156 . In one of said first of second cooling pipes 154 , 156 a coolant is provided to the fuel cell. In the other cooling pipe 156 , 154 said coolant is transferred from the fuel cell. Said first and second cooling pipes 154 , 156 may be coupled to a radiator not illustrated in FIG. 1 a. The coolant may be air, water, AC coolant such as R-134A, or any other suitable coolant. Said coolant may be used in a heat exchanger for separating the lubricant from the DME fluid. Another useful application of the coolant is to use its heat for heating the driver compartment. Another useful application of the heat is to transfer it to and through the engine and/or a cooling system for the engine in order to keep said engine warm while not running the engine.
[0048] An output 190 of the fuel cell 122 is connected to an inlet 192 of the condenser 120 via pipe 140 . In said condenser 120 , water is condensed to the bottom of said condenser 120 and separated from the rest of the gases coming from the fuel cell 122 . Not all of the hydrogen provided to the fuel cell 122 via the fifth pipe 150 is consumed and transformed into water and energy in the fuel cell 122 . The hydrogen which is not consumed in the fuel cell 122 (together with other gases not fully consumed in the fuel cell 122 , inter alia methane), so called rest fuel, are transferred to an inlet 196 of the after burner 124 via pipe 134 .
[0049] The after burner or combustor 124 may be constructed in similarity to the CO clean up device 108 . The material in the catalytic converter may be a catalyst of Noble metal and/or base metals supported on a monolith.
[0050] The heat produced by the after burner 124 when combusting the rest fuel from the fuel cell 122 is used to make steam of the water coming from the condenser 120 . From an outlet 198 of the combustor 124 is combusted gas transferred to a first inlet 181 of the heat exchanger 114 via pipe 132 . Water from the condenser 120 is transferred from a first outlet 197 of the condenser 120 to a second inlet 194 of the first heat exchanger 114 via pipe 138 . The heat of the combusted gas in the first heat exchanger 114 is heating the water to and above its boiling point in order to produce steam. Said steam from the first heat exchanger is transferred from a second outlet 183 to said third inlet 176 of the reformer 104 via said third pipe 130 .
[0051] In the embodiment of the invention illustrated in FIG. 1 a, a first inlet 189 of the second heat exchanger 180 is coupled to a first outlet 185 of the first heat exchanger 114 via a pipe 170 . In said pipe 170 combusted gases from the combustor 124 , which has passed through the first heat exchanger 114 , is provided to the second heat exchanger 180 . DME is fed to a second inlet 193 of said second heat exchanger 180 via pipe 190 . Said DME is separated from a lubricant within said second heat exchanger 180 . Said lubricant may be trapped in said second heat exchanger 180 or fed to the after burner for combustion. DME, which is pure and free from lubricant, is fed to the reformer 104 via a second pipe 126 , which is connected between a second outlet 187 of said second heat exchanger 180 and the second inlet 174 of said reformer 104 .
[0052] Combusted gases are transferred out of said second heat exchanger 180 via a first outlet 191 .
[0053] In an alternative embodiment the first and second heat exchangers 114 , 180 are the same unit.
[0054] The temperature in the reformer 104 may be between 350° C.-450° C. The temperature in the CO clean-up device 108 may be between 150° C. -180° C. The temperature in the Fuel cell 122 may be around 80° C. The temperature in the condenser 120 may be 80° C. -50° C. The temperature in the combustor may be between 400° C.-500° C. The temperature of the water before the first heat exchanger 114 may be less than 50° C. The temperature of the steam after the first heat exchanger may be above 140° C. The temperature of the combusted gas before the first heat exchanger may be 400° C. -500° C. The temperature of the combusted gas after the first heat exchanger may be 50° C.-200° C.
[0055] In FIG. 1 b an alternative example embodiment of the present invention is illustrated. This embodiment differs compared to the embodiment illustrated in FIG. 1 a in that it comprises a water gas shift 106 , a third heat exchanger 112 , a fourth heat exchanger 110 and a water tank 118 . It further differs in that the second heat exchanger 180 is connected in a somewhat different manner. The water gas shift 106 is connected with a first inlet 115 to the outlet 178 of the reformer with the pipe 160 . An outlet 117 of said water gas shift 106 is connected to a first inlet 119 of the third heat exchanger 112 . A first outlet 135 of said third heat exchanger 112 is connected to the first inlet 180 of the CO clean-up device 108 . A first inlet 127 of the water tank is connected to the first outlet 197 of the condenser 120 . A first outlet 129 of the water tank is connected to a first inlet 139 of the fourth heat exchanger 110 via pipe 158 . A second outlet 131 of said water tank 118 is connected to the first inlet 115 of the water gas shift 106 via pipe 144 . A first outlet 137 of said forth heat exchanger 110 is connected to a second inlet 121 of the third heat exchanger 112 via pipe 146 . A second outlet 133 of said third heat exchanger 112 is connected to the second inlet 194 of the first heat exchanger 114 via pipe 148 . The outlet 194 of CO clean-up device 108 is connected to a second inlet 123 of the forth heat exchanger 110 via pipe 150 . The second outlet 125 of said fourth heat exchanger 110 is connected to the first inlet 186 of the fuel cell 122 via pipe 152 .
[0056] In the embodiment as illustrated in FIG. 1 b, the rest gases from the fuel cell 122 is lean of hydrogen due to the set up of cold water injection into the water gas shift 106 , the third heat exchanger 112 and fourth heat exchanger 110 . The third heat exchanger 112 and the fourth heat exchanger 110 are cooling the gases introduced into the fuel cell 122 and increasing the water/steam content in the same gases.
[0057] A lower hydrogen content in the rest gases requires that the temperature of said gases are elevated compared to if the hydrogen content is higher as it is in the embodiment illustrated in FIG. 1 a. Increased rest gas temperature is performed by heating said gases in the second heat exchanger 180 , i.e., the gases introduced in the after burner 124 are heated by the exhaust gases from the after burner 124 in said second heat exchanger 180 .
[0058] The temperature in the water gas shift may be around 250° C.-350.
[0059] In the embodiment as illustrated in FIG. 1 b the steam provided to the reformer 104 is heated in three steps. A first step is in the fourth heat exchanger 110 , a second step is in the third heat exchanger 112 and a third step is in the first heat exchanger 114 .
[0060] In another example the first heat exchanger, which separates the DME fuel from the lubricant, is heated by the gases from the water-condenser. In this example the water condenser is working at some higher temperature and the last water is condensed by rejecting heat to the DME fuel.
[0061] It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims. | An auxiliary power unit (APU), a method of operating an APU and a vehicle comprising the APU are provided. The APU includes a fuel processor and a fuel cell, the fuel processor being provided with steam, air and dimethyl ether (DME). In order to avoid decreased functionality of the fuel cell caused by lubricants in the DME, a heat exchanger is provided for separating lubricant from the DME | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a heat exchanger for an air conditioner, and more particularly to a heat exchanger having a plurality of louver patterns above and below heat exchanging tubes perpendicularly passing through flat fins whereby the air currents flowing therethrough become turbulent and mixed and further a dead air region around each tube is reduced.
2. Description of the Prior Art
A conventional heat exchanger for an air conditioner includes, as shown in FIG. 1, a plurality of flat fins 1 arranged in a parallel relation to each other at predetermined intervals and a plurality of heat exchanging tubes 2 passing through the fins 1 perpendicular thereto. The air currents flow in the space defined between the fins 1 in the direction of the arrow in FIG. 1 and exchange heat with the fluid flowing in the heat exchanging tubes 2.
For a thermal fluid flowing around each flat fin 1, it has been known that the thickness of the thermal boundary layer 3 on both heat transfer surfaces of the fin 1 is gradually thickened in proportion to square root of the distance from the air current inlet end of the fin 1 as shown in FIG. 2. In this regard, the heat transfer rate of the fin 1 is remarkably reduced in proportion to the distance from the air current inlet end. Therefore, the above heat exchanger has a lower heat transfer efficiency.
For the thermal fluid flowing about each heat transfer pipe 102, it has been also known that, when lower velocity air currents flow in the direction of the arrow of FIG. 3, the air currents separate from the outer surface of the pipe 2 at portions spaced apart from the center point of outer surface of the pipe 4 at angles of 70-degree to 80-degree. Therefore, a dead air region 4 is formed behind each tube 2 in a direction of the air flow as shown in the hatched region of FIG. 3. In the dead air region 4, the heat transfer rate of the tube 2 is remarkably reduced so that the heat transfer efficiency of the above heat exchanger becomes worse.
In order to overcome the above problems, there has been proposed another solution as illustrated in FIGS. 4 and 5. This heat exchanger includes a plurality of heat exchanging tubes 2 which are fitted into the regularly spaced flat fins 1 such that the tubes 2 are perpendicular to the fins 1. The heat exchanger also includes a plurality of rectangular louver patterns P which are formed adjacent the tubes 2 passing through each fin 1, without any fin portions disposed between the tubes 2. Each louver 5a, 5b, 5c, 5d, or 5e is formed by bending at a given angle the louver's outer edges relative to the plane of the flat fin 1, respectively, by way of the cutting process. Also, the louvers are vertically positioned to the heat exchanging tubes 2.
The above-described louvers 5a, 5b, 5c, 5d and 5e make the air flow turbulent. This operation advantageously reduces the thickness of the thermal boundary layers formed on the fins 1. However, since upper and lower ends of each pattern of louvers are parallel to a tangent of the outer circumferential surface of the tube 2 and the patterns of louvers are generally rectangular, a dead air region still exists behind each tube 2 in a direction of the air flow. Also, there is a problem in that unmixed air currents flow in the spaces between the plurality of flat fins 1, and the expected improvement of the heat transfer effect due to mixing of air currents cannot be guaranteed.
Further, there is a problem in that said upper and lower edges of said louvers 5a to 5e are arranged in parallel relation to the air current flow S, resulting in an increased pressure drop that reduces the heat transfer performance.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide a heat exchanger which provides an improved heat transfer performance due to the turbulence and mixture of the air currents that flow in spaces between a plurality of flat fins, and also effectively reduces an air dead region found behind each tube in a direction of the air flow and thus improves the heat transfer performance.
Another object of the present invention is to provide the heat exchanger that provides (a) a draining function of condensed water generated on the heat exchanging tubes, (b) an enlargement of a whole surface area of the flat fins, and (c) an improved strength of the flat fins.
A heat exchanger for accomplishing the above objects is characterized in that vertical beads are formed on the flat fins and are situated above, below, in front of, and behind the heat exchanging tubes to provide (a) a draining function for condensed water generated on the heat exchanging tubes, (b) an enlargement of whole surface area of the flat fins, and (c) a reinforcement of the flat fins.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and aspects of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings in which:
FIG. 1 is a perspective view illustrating a conventional heat exchanger for an air conditioner;
FIG. 2 is an enlarged sectional view of a flat fin of the heat exchanger of FIG. 1, showing the characteristics of the thermal fluid flowing about the fin;
FIG. 3 is an enlarged sectional view of a the heat exchanging tube of the heat exchanger of FIG. 1, showing the characteristics of the thermal fluid flowing about the heat exchanging tube;
FIG. 4 is a front view of a flat fin of another conventional heat exchanger;
FIG. 5 is a sectional view of the flat fin taken along the section line A--A in FIG. 4;
FIG. 6 is a front view of a flat fin in accordance with a heat exchanger of the present invention;
FIG. 7 is a sectional view of the flat fin taken along the section line B--B in FIG. 6;
FIG. 8 is a sectional view of the flat fin taken along the section line C--C in FIG. 6; and
FIG. 9 is a schematic diagram explaining the air currents flow in the flat fin in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment according to the present invention will now be described in detail in accordance with the accompanying drawings. The same or corresponding elements or parts are designated with like references throughout the drawings.
Referring to FIG. 6, reference numeral 10 generally denotes a group of four angled louver patterns radially located around each tube 2, respectively. The louvers cause the air currents to be turbulent and to be mixed up, which effectively reduces a dead air region behind each tube 2 in a direction of the air flow and thus improves the heat transfer performance. Improvement is accomplished by a group of the angled louver patterns located above and below the tube 2, wherein the louver patterns located below tube 2 comprise a first louver pattern 20 configured to guide an air current flow in a first direction and a third louver pattern 40 inclined opposite to the first louver pattern 20 such that said guided air current is guided in an opposing second direction. Louver patterns arranged below the tube 2 comprise a second angled louver pattern 30 and a fourth louver pattern 50 inclined opposite to the second louver pattern as in the case of the first and third patterns, and wherein those louver patterns 10-50 are radially positioned relative to respective tubes 2 to encompass the tubes 2.
Also, the angled first and second louver patterns 20 and 30 are placed in mirror image relationship to each other such that the air currents flowing over both surfaces of the flat fin 1 and in a front half of the area between the tubes 2 become turbulent flow and are mixed up. Further, the angled third and fourth louver patterns 40 and 50 are similarly placed in mirror image relationship to each other such that the currents having passed the patterns 20 and 30 continue to pass the remaining rear half of the area between the tubes 2 and become turbulently mixed up, thereby reducing the dead air region.
Each of the first and second louver patterns 20, 30 has inclined strips or louvers (see FIG. 7), each of which has an upstream edge UE projecting past a first surface S' of the flat fin 1 and a downstream edge DE projecting past a second surface S" of the flat fin 1. Each strip or louver provides a slit formed to be perpendicular to the air flow. The strips of an inclined orientation according to the present invention may be formed by way of a cutting process. The third and fourth louver patterns 40, 50 are similar to those first and second louver patterns 20, 30, but the slits thereof are inclined in the opposite direction (see FIG. 7).
A roughly semi-circular base portion 60 occupies an area defined between upper ends of the first and third louver patterns 20, 40 and a lower outer circumference of a tube 2. With the base portion 60 interposed therebetween and further the tube 2 centered, the first and third louver patterns 20, 40 are radially oriented relative to the centered tube 2. Similarly, the second and fourth louver patterns 30, 50 are radially oriented relative to an upper outer circumference of a tube 2, with a certain round semi-circular base portion 60a interposed therebetween.
The first and third louver patterns 20, 40 and the second and fourth louver patterns 30, 50 are symmetrically formed relative to each other, these patterns being separated by a base portion 60b therebetween.
The louvers of each pattern are sequentially arranged without any base portion of the fin disposed therebetween and are directly formed by way of cutting process.
In the drawings, reference numerals 80 denote first beads which are positioned above or below a tube 2. Reference numerals 90 denote second beads positioned in front of or behind a tube 2. The beads, formed by way of a beading process, serve to drain condensed water that may be formed on the heat exchanging tubes 2, as well as to further reinforce the flat fin 1 and enlarge the surface area of the flat fin 1.
Namely, the first beads 80 are vertically separated by the round base portions 60 or 60a from a tube 2. The second beads 90 are horizontally separated from a tube 2 by base portions 60a.
Each bead is configured to project above the first surface S' of the flat fin 1, and is symmetrical relative to a central longitudinal axis thereof. Left and right halves of each bead are symmetrically bent at a suitable angle, respectively.
The first beads 80 respectively are positioned above and blow a tube 2 and are situated between the first and third louver patterns 20 and 40 and between the third and fourth louver patterns 30, 50. Each of the second beads 90 has a vertical length sized to be identical with the diameter of the tube 2.
An operation and effect of the heat exchanger for the air conditioner will be described.
When the air currents flow in the space defined between the fins 1 in the direction of the arrow S in FIG. 6, the air currents sequentially pass through the first and third louver patterns 20, 30 and then through the second and fourth patterns 40, 50 around tubes 2 in the directions of the arrows shown in FIG. 9. This operation allows the thermal flow from the heat exchanging tube 2 to be continuously transferred and to be turbulent and mixed up.
When the air currents flow in the spaces defined between adjacent fins 1 in the direction of the arrow S in FIG. 9, the air currents sequentially pass through the first and third louver groups 20 and 40, or the second and fifth louver groups 30, 50 while passing around the respective tubes 2. As the air current flowing along the first surface S' encounters the first louver group 20, some of the air is caused to flow through the fin via the slits defined by the louvers 70-75, whereby the air becomes transferred to the second surface S" of the fin. Simultaneously, that air becomes mixed with air that is already flowing along the second surface S" so as to become turbulent and mixed therewith. Thereafter, the air flowing along the second surface S" encounters the third louver group 40, and some of that air is caused to flow back through the fin via the slits formed by the louvers of the third louver group, and is thus transferred to the first surface S' where it becomes turbulent and mixed with air already flowing along the first surface S'.
The turbulent and mixed air currents continuously flow throughout a whole area around each tube 2, and are moved towards the rear of each tube 2, resulting in significantly less drop of the pressure and promotion of a smooth flow of the air currents.
The semi-circular base portions 60, 60a interposed between a tube 2 and the radially disposed first to fourth louver patterns 20 to 50 allow the turbulent air currents passing through said patterns 20 through 50 to be capable of further flowing into the dead air region. Thus, the dead air region becomes considerably reduced, and the heat transfer effect in the dead air region is further improved.
In addition, when the heat exchanger is used as an evaporator for a cooling apparatus or a condenser, so called condensed water is generated due to a temperature difference between a refrigerant flowing inside the heat exchanging tube 2 and the air currents flowing in the space between the flat fins 1 (e.g., a dew-forming phenomenon). In this regard, the beads 80, which enlarge the surface area of the flat fin 1, provide paths along which the condensed water can readily flow.
As described above, this invention prevents the pressure drop of the flowing air currents and provides turbulence and mixture of the air currents. Further, the invention improves the hear transfer effect and reduces the dead air region around the heat exchanging tubes. Therefore, the continuity of the heat transfer from the tube into other places can be guaranteed. Further, the improved heat transfer into a center portion between a plurality of heat exchanging tubes is also provided. Moreover, the beads provide the enlargement of the surface area of the flat fin, along with paths through which the generated condensed water flow. | A heat exchanger for an air conditioner comprises parallel flat fins for conducting air flows therebetween, and parallel tubes passing perpendicularly through the flat fins for conducting heat exchanging fluid. Each fin includes vertical beads disposed above, below, in front of and behind the tubes for draining condensed water. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. application Ser. No. 13/524,794 filed on Jun. 15, 2012, which claims priority to and the benefit of Korean Patent Application No. 10-2011-0058979 filed in the Korean Intellectual Property Office on Jun. 17, 2011, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to a method for sensing pressure according to touch, and more particularly, to an apparatus for sensing pressure using an optical waveguide which may measure a change in an amount of light passing through the optical waveguide when pressure is applied to the optical waveguide and sense intensity and a location of the applied pressure according to the measured change in the amount of the light, and a method thereof.
BACKGROUND ART
In general, a touch pad is an input device that may sense a location of a contact point by contacting another object such as a finger or a pen on a pad location of a point corresponding to a screen of a display device. In recent years, the touch pad has been used as a representative method instead of a mouse of a notebook computer. A touch screen is a device that a user contacts a picture or a character visually displayed on a screen by hand or with a pen to perform a command by attaching a transparent sensor having the same size as that of a display device to a screen coordinate and a contact point coordinate to correspond to each other.
The types of the foregoing touch panel and touch screen may be classified for each medium sensing a contact signal. There are a resistive type, a surface acoustic wave (SAW) type, a capacitive type, and the like as representative types of the touch pad or the touch screen.
In a resistive type touch screen panel, insulation bars are provided between a glass or transparent plastic plate and a polyester film using a resistive material at predetermined distance such that the glass or transparent plastic plate and the polyester film do not contact in such a way that the resistive material is coated on the glass or transparent plastic plate and the polyester film is covered thereon. When the user touches the resistive type touch screen panel, a resistance value varies and an applied voltage also varies due to a physical change in the insulation bars. A contact location is recognized according to the variation in the applied voltage.
The SAW type touch screen panel includes a transmitter, a reflector, and a receiver. The transmitter generates an ultrasonic wave and is attached to one corner of glass. The reflector reflects a sound wave and is spaced apart from the transmitter by a predetermined distance. The receiver is attached to another side of the reflector. When a panel contacts an object such as a finger preventing the sound wave, some ultrasonic wave is absorbed. The SAW type touch screen panel uses a method of calculating a location where the change occurs and simultaneously recording a contact location.
In a capacitive type touch screen, when both sides of glass are coated with a transparent special conductive metal and a voltage is applied to four corners of a screen, a high frequency is generated on a surface of the touch screen. In this case, if a conductive object such as a user's finger contacts on the capacitive type touch screen, a high frequency component become low. Such digital data is analyzed by a controller to find out a contact location. The method is not influenced by external factors and a panel has high transparency and thus is the most frequently used technology.
An infrared type touch screen uses straight attribute of light, and is a technology using an attribute that is blocked and is not advanced when there is an obstacle. In a basic structure of a panel, a plurality of infrared light emitting diodes being an emission device and a photo-transistor being a receiving device are disposed to face each other, and an optical grating frame is made and mounted around a front cover of a monitor. An object such as a finger touches the infrared type touch screen, because light is blocked and is not sensed by a photo-transistor of an opposite side, a touched location of a cell is recognized.
Because only on/off of an existing touch pad is sensed based on an input signal, whether an operation is performed suited to the intention of a user can be known by only a change in a corresponding picture or button. Accordingly, because an error with respect to a desired operation of the user can be appreciated according to presence of a function operation, delay occurs for some time. When the touch pad is used by only on/off input as described above, sensitivity of the touch pad may not be adjusted, operation erroneously performed cannot be prevented when a key is strongly input.
An existing touch screen touches a screen based on a screen, namely, a panel to recognize a location, and may perform a multi-touch function, a drag function, and the like in some cases. However, the multi-touch function, the drag function, and the like are performed by a method capable of being used in a plane, and thus it is difficult to implement a previous resolution and precision in an irregular side. As in the touch pad, because the existing touch screen recognizes only on/off input, namely, touch, the touch screen may cause an erroneous operation of desired input.
Such problems occur because the touch screen cannot recognize pressure which the user applies.
SUMMARY OF THE INVENTION
The present invention has been made in an effort to provide an apparatus for sensing pressure using an optical waveguide which may measure a change in an amount of light passing through the optical waveguide when pressure is applied to the optical waveguide and sense intensity and a location of the pressure according to the measured change in the amount of light, and a method thereof.
The present invention further provides an apparatus for sensing pressure using an optical waveguide which may sense the intensity of pressure by using a change in amount of light passing through the optical waveguide and sense intensity and a location of the pressure so as to allow a user to recognize the sensed intensity of pressure, and a method thereof.
However, an object of the present invention is not limited to the above-mentioned matters, and other non-mentioned objects will become apparent to those skilled in the art based on the following explanation.
An exemplary embodiment of the present invention provides an apparatus for sensing pressure using an optical waveguide sensor, including: a light source radiating light; an optical waveguide panel emitting some of the radiated light to the outside through a plurality of light transmitting regions previously formed, and changing an amount of totally reflected light according to pressure applied to at least one of the plurality of light transmitting regions; a detector detecting the amount of light; and an analyzer determining intensity and a location of the pressure according to the detected amount of light.
The optical waveguide panel may include: a first cladding layer; a core layer formed in an upper portion of the first cladding layer in a grating pattern, and totally reflecting and transmitting the light radiated from the light source; and a second cladding layer formed in an upper portion of the first cladding layer on which the core layer is formed, and having the light transmitting region where holes are formed at a predetermined interval at the upper portion of the core layer, and some of the light passing through the core layer are emitted to the outside through the formed holes.
The optical waveguide panel may include: a first cladding layer; a core layer formed in an upper portion of the first cladding layer in a grating pattern, and having the light transmitting region on which the first cladding layer has a bent shape at a predetermined interval, and some of light radiated from the light source are emitted to the outside; and a second cladding layer formed in an upper portion of the first cladding layer on which the core layer is formed.
The optical waveguide panel may include: a first cladding layer; a core layer formed in an upper portion of the first cladding layer in a grating pattern, and totally reflecting and transmitted to the light radiated from the light source; a second cladding layer formed in an upper portion of the first cladding layer on which the core layer is formed; and a photo elastic layer inserted into the second cladding layer at a predetermined interval and emitting some of the light passing through the core layer to the outside.
The photo elastic layer may use a photo elastic material having a refraction index different from that of the second cladding layer, and a side of the photo elastic layer may contact the core layer.
The optical waveguide panel includes an electric elastic layer that may be formed in a lower portion of the first cladding layer, and receiving an electric signal according to the intensity of the pressure applied to the light transmitting region such that physical properties in the electric elastic layer vary.
When the electric elastic layer receives the electric signal, the physical properties in the electric elastic layer may vary left and right.
When the electric elastic layer receives the electric signal, the physical properties in the electric elastic layer may vary upward and downward.
The more the amount of light is, the higher the intensity of the pressure may be, and the less the amount of light is, the lower the intensity of the pressure may be.
Another exemplary embodiment of the present invention provides an apparatus for sensing pressure using an optical waveguide sensor, including: a light source radiating light; an optical waveguide panel emitting some of the radiated light to the outside through a plurality of light transmitting regions previously formed, and changing an amount of light totally reflected according to pressure applied to at least one of the plurality of light transmitting regions; a detector detecting the amount of light; and an analyzer determining intensity and a location of the pressure according to the detected amount of light, wherein the optical waveguide panel receives an electric signal from the analyzer according to the intensity of the pressure, and physical properties in the optical waveguide panel vary in a region to which the pressure is applied.
When the optical waveguide panel receives the electric signal, the physical properties in the optical waveguide panel may vary left and right.
When the optical waveguide panel receives the electric signal, the physical properties in the optical waveguide panel may vary upward and downward.
The more the amount of light is, the higher the intensity of the pressure may be, and the less the amount of light is, the lower the intensity of the pressure may be.
Yet another exemplary embodiment of the present invention provides a method for sensing pressure using an optical waveguide sensor, including: radiating light to an optical waveguide panel to emit some of the light outside through a plurality of light transmitting regions previously formed; detecting an amount of light changed according to pressure applied to at least one of the plurality of light transmitting regions; and determining intensity and a location of the pressure according to the detected amount of the light.
The method may further include applying an electric signal to a region to which pressure of the optical waveguide panel is applied according to the intensity of the pressure to vary physical properties in the region.
The varying of the physical properties may include applying an electric signal to a region to which pressure of the optical waveguide panel is applied according to the intensity of the pressure to vary physical properties in a left side and a right side of the region.
The varying of the physical properties may include applying an electric signal to a region to which pressure of the optical waveguide panel is applied according to the intensity of the pressure to vary physical properties in up and down directions of the region.
The more the amount of light is, the higher the intensity of the pressure may be, and the less the amount of light is, the lower the intensity of the pressure may be.
According to exemplary embodiments of the present invention, it is possible to measure a change in an amount of light passing through the optical waveguide when pressure is applied to the optical waveguide and to sense intensity and a location of the applied pressure according to the measured change in the amount of light, thereby more precisely detecting the intensity and location of the pressure.
It is also possible to sense the intensity of the pressure by using a change in an amount of light passing through the optical waveguide according to the applied pressure to allow a user to recognize the sensed pressure intensity, thereby controlling the pressure intensity.
It is also possible to sense the intensity of the pressure by using a change in an amount of light passing through the optical waveguide according to the applied pressure to allow a user to recognize the sensed intensity of the pressure, thereby implementing various user interfaces.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exemplary diagram illustrating an apparatus for sensing pressure according to an exemplary embodiment of the present invention.
FIGS. 2A, 2B and 2C are first exemplary diagrams illustrating a principle for sensing pressure according to the exemplary embodiment of the present invention.
FIGS. 3A, 3B and 3C are second exemplary diagrams illustrating a principle for sensing pressure according to the exemplary embodiment of the present invention.
FIGS. 4A, 4B and 4C are third exemplary diagrams illustrating a principle for sensing pressure according to the exemplary embodiment of the present invention.
FIG. 5 is an exemplary diagram illustrating another configuration of an optical waveguide panel according to the exemplary embodiment of the present invention.
FIGS. 6A, 6B and 6C are exemplary diagrams illustrating a principle for returning a physical stimulation according to the exemplary embodiment of the present invention.
FIG. 7 is an exemplary diagram illustrating a process of processing a physical stimulation according to the exemplary embodiment of the present invention.
FIG. 8 is an exemplary diagram illustrating a method for sensing pressure according to an exemplary embodiment of the present invention.
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
Hereinafter, an apparatus and a method for sensing pressure using an optical waveguide according to exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, namely, FIGS. 1 to 8 . The exemplary embodiments of the present invention will be described in detail based on parts necessary to understand operations and functions of the present invention. Throughout the specification, in giving reference numerals to elements of each drawing, like reference numerals refer to like elements even though like elements are shown in different drawings.
An exemplary embodiment of the present invention suggests an approach which may measure a change in an amount of light passing through an optical waveguide when pressure is applied to the optical waveguide and sense intensity and a location of the applied pressure according to the measured change in the amount of light, and may allow a user to recognize the sensed intensity of the pressure, and a method thereof. Here, the optical waveguide refers to an optical fiber designed such that an optical signal is transferred.
FIG. 1 is an exemplary diagram illustrating an apparatus for sensing pressure according to an exemplary embodiment of the present invention.
As shown in FIG. 1 , the apparatus for sensing pressure according to the exemplary embodiment of the present invention may include a first light source 110 , a second light source 120 , an optical waveguide panel 200 , a first detector 310 , a second detector 320 , and an analyzer 400 , as a user input device for sensing pressure according to touch. For example, the user input device may be a concept generally including a key pad, a touch pad, a touch screen, and the like.
The first light source 110 and the second light source 120 may radiate light to the optical waveguide panel 200 , respectively. For example, the first light source 100 may radiate the light in a transverse direction of the optical waveguide panel 200 , and the second light source 120 may radiate the light in a longitudinal direction of the optical waveguide panel 200 .
The optical waveguide panel 200 may include a core layer 210 transmitting light and a cladding layer 220 surrounding the core layer 210 and preventing light from being emitted to the outside of the core layer 210 . Here, the core layer 210 and the cladding layer 220 have different refraction indexes such that the core layer 210 totally reflects and transmits the light. The core layer 210 may be formed in a grating pattern.
The optical waveguide panel 200 may transmit the light, and an amount of the transmitted light is changed according to intensity of pressure applied from the user. Particularly, the optical waveguide panel 200 radiates some of the light outside through a plurality of light transmitting regions previously formed, and changes an amount of totally reflected light according to pressure applied to at least one of the plurality of light transmitting regions.
That is, the higher the intensity of the pressure is, the more the amount of light passing through the optical waveguide panel 200 is. The lower the intensity of the pressure is, the less the amount of light passing through the optical waveguide panel 200 is.
The light transmitting region may be implemented in various forms, and several examples thereof will be described below.
The optical waveguide panel 200 may return a physical stimulation to the user according to a change in the amount of light. Here, the physical stimulation may refer to tactile indicating whether a user contacts or the intensity of the touch. For example, through the function of real-time returning the physical stimulation, functions of various user interfaces, for example, a key pad, a multi-key pad, a touch screen, a mouse, and the like may be implemented.
The first detector 140 may detect an amount of light passing through a plurality of core layers arranged parallel with each other at predetermined intervals in a transverse direction, and the second detector 150 may detect an amount of light passing through a plurality of core layers arranged parallel with each other at predetermined intervals in a longitudinal direction. Here, a photo transistor or the like may be used as the first detector 140 and the second detector 150 .
The analyzer 160 may determine a touched intensity and a touched location of the pressure based on the detected amount of the light. The analyzer 160 may apply an electric signal to the optical waveguide panel to apply a physical stimulation to the user according to the intensity of the pressure applied to the light transmitting region.
FIGS. 2A, 2B and 2C are first exemplary diagrams illustrating a principle for sensing pressure according to the exemplary embodiment of the present invention.
FIGS. 2A, 2B and 2C are cross-sectional views of the optical waveguide panel 200 according an exemplary embodiment of the present invention. The optical waveguide panel 200 may include a first cladding layer 221 , a core layer 210 formed in an upper portion of the first cladding layer 221 , a second cladding layer 222 formed in an upper portion of the core layer 210 , and the like.
The second cladding layer 222 has a light transmitting region 223 a where apertures or holes are formed at a predetermined interval at upper portions of the core layer 210 , and some of light passing through the core layer 210 are emitted to the outside through the formed holes. In this case, a distance between the holes may be formed to have 1 mm or less.
In FIG. 2A , if the user does not apply pressure to the optical waveguide panel 200 from the outside, some of the light passing through the core layer 210 are emitted to the outside through all the formed holes.
In FIG. 2B , if the user applies first pressure to a predetermined hole, some of the light passing through the core layer 210 are emitted to the outside through a hole to which the pressure is applied. However, because the amount of light emitted to the outside in FIG. 2B is reduced in comparison with the case of FIG. 2A , an amount of totally reflected and transmitted light is increased. In FIG. 2C , if the user applies second pressure higher than the first pressure hole, an external path of a hole is blocked such that the light passing through the core layer is not emitted to the outside.
In this case, intensity of the first pressure and intensity of the second pressure are set according to the amount of light.
As described above, the amount of light passing through the core layer is changed according to intensity of pressure applied to the hole. That is, the higher the pressure intensity applied to the hole is, the more the amount of light passing through the core layer is. The lower the pressure intensity applied to the hole is, the less the amount of light passing through the core layer is.
FIGS. 3A, 3B and 3C are second exemplary diagrams illustrating a principle for sensing pressure according to the exemplary embodiment of the present invention.
FIGS. 3A, 3B and 3C are cross-sectional views of the optical waveguide panel according an exemplary embodiment of the present invention. The optical waveguide panel may include a first cladding layer 221 , a core layer 210 formed in an upper portion of the first cladding layer 221 , a second cladding layer 222 formed in an upper portion of the core layer 210 , and the like.
The core layer 210 has a light transmitting region 223 b where the first cladding layer 221 has a convex or bent shape at a predetermined interval, and some of light are emitted to the outside at a bent shape. Here, the bent shape may be implemented in various shapes such as a triangle shape, a circle, an ellipse, or a square. In this case, a distance between the bent shapes may be formed to have 1 mm or less.
In FIG. 3A , if the user does not apply pressure from the outside, some of the light passing through the core layer 210 are emitted to the outside through all the bent shapes. In this case, the light is emitted to the first cladding layer 221 or the second cladding layer 222 through the bent shapes.
In FIG. 3B , if the user applies first pressure in a predetermined bent shape, some of the light passing through the core layer 210 are emitted to the outside through a bent shape to which pressure is applied. However, because the amount of light emitted to the outside in FIG. 3B is reduced in comparison with the case of the FIG. 3A , an amount of totally reflected and transmitted light is increased. In FIG. 3C , if the user applies second pressure higher than the first pressure in a predetermined bent shape, the bent shape is spread in a straight shape such that the light passing through the core layer 210 is not emitted to the outside.
As described above, an amount of light passing through the core layer is changed according to intensity of the pressure applied to the bent shape. That is, the higher the intensity of the pressure applied to the bent shape is, the more the amount of the light passing through the core layer is. The lower the intensity of the pressure applied to the bent shape is, the less the amount of the light passing through the core layer is.
FIGS. 4A, 4B and 4C are third exemplary diagrams illustrating a principle for sensing pressure according to the exemplary embodiment of the present invention.
FIGS. 4A, 4B and 4C are cross-sectional views of the optical waveguide panel 200 according an exemplary embodiment of the present invention. The optical waveguide panel 200 may include a first cladding layer 221 , a core layer 210 formed in an upper portion of the first cladding layer 221 , a second cladding layer 222 formed in an upper portion of the core layer 210 , and a photo elastic layer 223 c.
The photo elastic layer 223 c is inserted into the second cladding layer 222 at a predetermined interval as a light transmitting region 223 c . A side of the photo elastic layer 223 c is formed to contact the core layer 210 , and the photo elastic layer 223 c emits some of the light passing through the core layer 210 to the outside. In this case, the photo elastic layer 223 c uses a photo elastic material having a refraction index different from that of the second cladding layer 222 . A distance between the photo elastic layers 223 c may be formed to have 1 mm or less.
In FIG. 4A , if the user does not apply pressure from the outside, some of the light passing through the core layer are emitted to the outside through all the formed photo elastic layers.
In FIG. 4B , if the user applies first pressure to a predetermined photo elastic layer, some of the light passing through the core layer are emitted to the outside through the photo elastic layer to which pressure is applied. Because the amount of light emitted to the outside in FIG. 4B is reduced in comparison with the case of the FIG. 4A , an amount of totally reflected and transmitted light is increased.
In FIG. 4C , if the user applies second pressure higher than the first pressure to a predetermined photo elastic layer, an external path of a hole is blocked such that the light passing through the core layer is not emitted to the outside.
As described above, an amount of light passing through the core layer is changed according to intensity of the pressure applied to the photo elastic layer. That is, the higher the intensity of the pressure applied to the photo elastic layer is, the more the amount of the light passing through the core layer is. The lower the intensity of the pressure applied to the photo elastic layer is, the less the amount of the light passing through the core layer is.
FIG. 5 is an exemplary diagram illustrating another configuration of an optical waveguide panel according to the exemplary embodiment of the present invention.
FIG. 5 is a partially cross-sectional view of the optical waveguide panel according to an exemplary embodiment of the present invention. The optical waveguide panel may include a first cladding layer 221 , a core layer 210 formed in an upper portion of the first cladding layer 221 , a second cladding layer 222 formed in an upper portion of the core layer 210 , and an electric elastic layer 223 c.
The construction of emitting some of light transmitting a core layer to an outside is identical to that shown in FIGS. 2 to 4 , and thus the description thereof is omitted.
The electric elastic layer 224 is formed in a lower portion of the first cladding layer 221 . When the electric elastic layer 224 receives an electric signal according to the intensity of the pressure applied to a light transmitting region, physical properties in the electric elastic layer 224 vary, that is, the electric elastic layer 224 is contracted or expanded. That is, because a contracted degree of the electric elastic layer 224 is changed according to intensity of pressure, every time the pressure is applied, the electric elastic layer 224 returns a physical stimulation to a user.
In this case, physical properties in the electric elastic layer 224 vary in left and right directions or up and down directions.
FIGS. 6A, 6B and 6C are exemplary diagrams illustrating a principle for returning a physical stimulation according to the exemplary embodiment of the present invention.
As shown in FIG. 6A , if the user does not apply pressure to a light transmitting region, some of the light passing through the core layer are emitted to the outside through all the formed photo elastic layers, and physical properties in the electronic elastic layer do not vary.
In FIG. 6B , if the user applies first pressure to a predetermined light transmitting region, some of the light passing through the core layer are emitted to the outside through a light transmitting region to which the pressure is applied. However, because the amount of light emitted to the outside in FIG. 6B is reduced in comparison with the case of the FIG. 6A , an amount of totally reflected and transmitted light is increased. An electric signal corresponding to the first pressure is applied to the electric elastic layer 224 such that physical properties in the electric elastic layer 224 vary, that is, the electric elastic layer 224 is significantly contracted upward and downward.
In FIG. 6C , if the user applies second pressure higher than the first pressure to a predetermined light transmitting region, an external path of the light transmitting region is blocked such that the light passing through the core layer is not emitted to the outside. An electric signal corresponding to the second pressure is applied to the electric elastic layer such that the physical properties in the electric elastic layer vary, that is, the electric elastic layer is contracted upward and downward larger than that of FIG. 6A .
FIG. 7 is an exemplary diagram illustrating a process of processing a physical stimulation according to the exemplary embodiment of the present invention.
FIG. 7 shows in detail a process of applying how to feedback if pressure corresponding to a desired operation is applied using an input device.
First, when there is no pressure, the input device sets a variable PressDownState to zero (PressDownState=0) (S 710 ). If the pressure is applied, the input device determines whether a magnitude of the applied pressure is lower than a level 1 (S 720 ). When the magnitude of the applied pressure is not lower than the level 1 , the input device may determine whether the magnitude of the applied pressure is level 1 (S 730 ).
That is, when the user increases the pressure applied to an upper part of the input device constant so that the magnitude of the pressure reaches first pressure or the level 1 , a physical stimulation or tactile feedback is generated (S 740 ). In this case, when the magnitude of the pressure reaches level 1 using the variable PressDownState, a tactile output is generated only once. That is, before the pressure is applied again in a state that pressure lower than or equal to the level 1 is applied, generated tactile feedback is not regenerated.
Next, in case where there is no input, if pressure at level 1 is applied in a state that the variable PressDownState is set to zero (PressDownState=0), the variable PressDownState is set to 1 (PressDownState=1) (S 750 ).
Subsequently, if the pressure is continuously applied, the input device determines whether the magnitude of the pressure is equal to or higher than level 1 (S 760 ). When the magnitude of the pressure is equal to or higher than level 1 , the input device may determine whether the magnitude of the pressure is at level 2 (S 770 ).
That is, when the magnitude of the pressure exceeds level 1 and reaches level 2 , the user generates a new tactile output (S 780 ). In this case, a tactile output when the pressure reaches level 2 provides another pattern having intensity higher than intensity or having the stimulation number greater than the stimulation number when the pressure reaches level 1 such that a user may intuitively know the applied pressure by oneself. In this case, as described above, when the pressure reaches level 2 , a moment tactile output is generated only once.
Next, if pressure of level 2 is applied in a state that the variable PressDownState is set to 1 (PressDownState=1) at pressure of level 1 , the variable PressDownState is set to 2 (PressDownState=2) (S 790 ).
In this case, before the magnitude of the pressure is reduced to level 2 or less and then is increased, for example, before the magnitude of the pressure is reduced to level 1 and then is increased to level 2 , a tactile output corresponding to level 2 is not generated. In this case, only when the pressure is continuously increased using a variable PressDownState in a previous state, the tactile output is generated.
FIG. 8 is an exemplary diagram illustrating a method for sensing pressure according to an exemplary embodiment of the present invention.
As shown in FIG. 8 , an input device according to an exemplary embodiment of the present invention may radiate light to an optical waveguide panel, and radiate light in a transverse direction and a longitudinal direction of the optical waveguide panel, respectively (S 810 ).
Next, the input device may detect an amount of light passing through the optical waveguide panel (S 820 ), and determine intensity and a location of pressure according to the detected amount of the light (S 830 ). Here, the intensity of the pressure may be divided into first pressure and second pressure, and may be divided into two or more as needed.
Next, the input device may generate an electric signal corresponding to the intensity of pressure, and apply the generated electric signal to a region to which the pressure of the optical waveguide panel is applied based on the location of the pressure (S 840 ). That is, the input device may apply a first electric signal to a region to which pressure is applied according to first pressure and a second electric signal to a region to which the pressure is applied according to second pressure, so as to transfer different physical stimulations to a user according to the intensity of the pressure.
As described above, the apparatus and the method for sensing pressure using an optical waveguide according to the exemplary embodiments of the present invention have been described and illustrated in the drawings and the specification. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | Disclosed are an apparatus and a method for sensing pressure using an optical waveguide sensor. The apparatus for sensing pressure using an optical waveguide sensor, includes: a light source radiating light; an optical waveguide panel emitting some of the radiated light outside through a plurality of light transmitting regions previously formed, and changing an amount of totally reflected light according to pressure applied to at least one of the plurality of light transmitting regions; a detector detecting the amount of light; and an analyzer determining intensity and a location of the pressure according to the detected amount of light. | 6 |
This is a division of application Ser. No. 918,947 filed June 26, 1978, now U.S. Pat. No. 4,202,188.
BACKGROUND OF THE INVENTION
This invention relates to a method for applying a liquid on a moving web in patterns.
A method for applying a liquid on a moving web utilizing a liquid shroud falling on the web from above which is interrupted in a pattern and to apparatus suitable for carrying out this method along with a dyeing device assembled thereto is disclosed, in principle, by Patent DL No. 44 964. However, this patent only schematically illustrated the interruption of the shroud without disclosing a practical embodiment. Such an embodiment is the subject of the German Offenlegungschrift No. 23 35 234. In the disclosed device channels, which can be brought into the descent path of the shroud in a controlled manner and which then conduct the liquid found there into a collecting tray, are provided over the width of the web side by side for the purpose interrupting the liquid shroud, so that the web receives no liquid for the pattern at the locations of the channels. By suitably controlling the individual channels, a given patterns can be achieved, the appearance of which, however, is determined by the longitudinal stripes or sections thereof which correspond to the channels.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method using apparatus of the type mentioned at the outset wherein the liquid can be applied in a freer and more irregular pattern.
According to the present invention, the solution of this problem comprises blowing a fluid medium transversely against the shroud to displace portions thereof without affecting its cohesiveness.
The fluid medium may be, in particular, air, but may also be a liquid when then must be compatible with the other liquid, of course.
By blowing on the air, no liquid is removed from the falling shroud. Instead, the amount of liquid uniformly available over the width of the web is merely made nonuniform by displacing the flow filaments of the falling liquid to one side at the point where a "hole" is made in the shroud by the blowing, and the filaments settle on thy web, at the one side, in larger amounts than in the vicinity of the "hole".
Blowing liquid directed against a web is known per se from German Auslegeschrift No. 1 460 349. In the disclosed system, however, the liquid is sprayed against the web from adjacent nozzles and thus does not form a cohesive shroud, and the liquid is kept away from the web by the blowing.
In the preferred embodiment of the present invention, the blowing of the fluid medium against the shroud is interrupted in a controlled manner.
In this manner, the application of the liquid is not only made nonuniform in the transversal direction (by the blowing), but the nonuniformity is also made variable in the longitudinal direction, so that the variety of patterns increases.
One important embodiment of the method of the present invention for dyeing nap textiles, and especially rugs, in patterns comprises interrupting several dyeing liquid shrouds in patterns by blowing and applying the shrouds to the web sequentially wet on wet. The dyeing liquids may, in particular, have different viscosities.
A pattern is then obtained by the superposition and merging of the dyeing liquids which are applied, each by itself, interrupted in a pattern. Through suitable choice and adjustment of different dyeing liquids and the sequence in time of their application, rug patterns can be obtained which can be achieved with no other method of pattern application.
The present invention is also embodimed in apparatus for applying a liquid on a moving web in a pattern, comprising a device, arranged above the web, for producing a liquid shroud which falls on the web and extends across the web, and an arrangement which is provided between the device for producing the liquid shroud and the web, and which interrupts the falling shroud in a pattern before it strikes the web, and is characterized by the feature that the arrangement comprises at least one nozzle which points toward the falling shroud, and by means of which a fluid medium can be blown transversely against the shroud.
So that the effect of the nozzles can be varied, the discharge direction of at least one of the nozzles can be varied, and at least one of the nozzles is also movable, particularly perpendicularly and/or parallel to the shroud.
Further variations are possible by providing a splitting element which splits the nozzle jet between at least one of the nozzles and the shroud.
The development of the nozzle jets is influenced thereby and the jet strikes the shroud in changed form.
Also, the effect of the splitting elements can be varied inasmuch as at least one of them is movable, particularly perpendicularly perpendicularly and/or parrallel to the shroud.
In one advantageous embodiment, the splitting elements consist of a grid arranged in front of the nozzles.
A facility for carrying out the above-mentioned method for dyeing nap textiles, particularly rugs, comprises several of the devices described above, which are arranged and operate in tandem in the travel direction of the web.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an individual apparatus for dyeing rug webs in patterns.
FIG. 2 is a partial view corresponding to FIG. 1, from above onto the nozzle arrangement.
FIG. 3 is a side view of an embodiment modified by adding a grid.
FIG. 4 is a partial view corresponding to FIG. 3 from above.
FIG. 5 is a side view of a rug dyeing facility.
DETAILED DESCRIPTION OF THE INVENTION
The apparatus 10 in FIG. 1 is used for dyeing a rug web 1, horizontally advancing in the direction of the arrow 9, in patterns. Across and above the rug web 1, a trough 2 with dyeing liquid is arranged. A cylinder 3 has its lower part immersed in the dyeing liquid and takes dyeing liquid along at its surface when it rotates in the direction of the arrow 4 about the shaft 5 which is aligned transversely to the web of material. It is removed from the cylinder surface by a wiper 6 which is arranged on the descending side of the circumference of the cylinder 3 and points down toward the rug web 1 at an angle. The liquid flows over the surface of the wiper 6 and drops down from the lower edge of the latter in a shroud 8 which is uninterrupted across the rug web.
The above constitutes the apparatus for generating the liquid shroud.
Between the lower edge 7 of the wiper 6 and the rug web 1, a nozzle arrangement 20 is provided. The nozzle arrangement 20 comprises individual nozzles 21 which are realized in the illustrated embodiment as flat (duckbill) nozzles arranged parallel to the rug web 1, side by side close together. The nozzles are connected to a common air supply line 22 and can be connected to the air supply line 22 or separated therefrom by valves 23 which, for instance, are operated electrically.
The nozzles 21 blow crosswise against the falling shroud 8 and make the latter uneven in the striking area of the air jet in that the flow filaments of the liquid falling in the shroud 8 are displaced, as indicated in FIG. 2 for the middle nozzle. Because of the surface tension, the liquid shroud 8 is not simply displaced parallel to the travel direction of the rug web 1, which would not result in differences of the liquid application in the transversal direction, but the flow filaments accumulate preferentially in the zones 24 on both sides of the striking zone 25, as can be seen from FIG. 2. The liquid shroud 8 falls uninfluenced and uniformly in front of nozzles 21 which are not in operation, as can be seen in FIG. 1, where every second nozzle is inoperative.
In FIG. 1, the nozzle arrangement 20 is provided below the dyeing liquid trough 2. While this arrangement has advantages as far as space requirements are concerned, it is not essential for the operation; the nozzles 21 can also blow against the direction of travel.
The effect of the blasting can now be varied in different ways, as may be seen from FIGS. 2 to 4.
First, the entire nozzle arrangement can supported so as to be movable, according to FIG. 2, parallel to the travel direction 9 of the rug web as indicated by arrow 27. The effect of the impinging air jet is different, depending on whether the mouth of the nozzles 21 is close to the shroud 8 or farther away from the same.
The nozzle arrangement can furthermore be supported for rotation is shown by FIG. 3, in the direction of the arrow 28 upward and downward about a transversal axis and, as per FIG. 4, in the direction of the arrow 29 in a plane extending parallel to the rug web 1. The rotatability can be obtained in a simple manner by connecting the nozzle 21 to the valve 23 via an elastic tube 26. The movement is accomplished by means of suitable driving means which engage at the nozzles 21 but are not shown.
The effect of the nozzles 21 can furthermore be influenced by splitting elements arranged between the nozzles and the falling shroud 8 such as the grid 30 in FIGS. 3 and 4. The grid 30 and similar splitting elements placed in the jet of the nozzles 21 may likewise be movable in various ways, as is indicated by the arrow 31 in FIG. 4.
Other nozzle designs can also be used instead of the shape of the nozzles diagrammatically indicated in the figures. Similarly, a different fluid medium, for instance, a liquid can be blown against the falling shroud 8 instead of the air mentioned up to now. Of course, this liquid must be compatible with the dyeing process. In the case of aqueous dyeing liquids water can be used. An additional effect takes place here inasmuch as the liquid which gets onto the web additionally, influences the running of the dyeing liquid on the web and thus brings an additional component into the pattern.
In FIG. 5 a rug dyeing machine is shown, in which five devices 10 are connected in series. The five devices 10 operate wet on wet. The individual dyeing liquids applied in patterns get onto the nap of the rub web 1 one after the other, sink in to different depths, merge into each other at the edges and result in a quite unique, varied pattern which can be obtained with no other dyeing process. It is not a droplet-type pattern but a pattern with larger dyed zones which can be different particularly in the depth direction of the rug. If hues of different saturation of a color are used, uniquely changing appearances of the pattern can be produced. Through the size of the individual pattern fields, animation of the pattern is obtained, which has a pleasing effect on the eye, especially in the case of large areas such as can be considered for display goods. By using dyeing liquids with different viscosities, the ability to sink in and the interaction with the other dyeing liquids can be controlled. Dyeing liquids which exhibit differences with regard to other criteria, which have an effect on the shape of the pattern can, of course, also be used. | In order to pattern a web using a method for applying a liquid to the moving web on which a cohesive liquid shroud falling on the web from above is interrupted in a pattern, a fluid medium is blown transversely against the falling shroud to displace portions thereof without affecting its cohesiveness. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This U.S. patent application is a continuation of, and claims priority under 35 U.S.C. §120 from, U.S. patent application Ser. No. 12/464,844, filed on May 12, 2009, which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present teachings relate to devices and methods for controlling the reflection of emitted beams to influence navigation of an autonomous device having a navigation sensor utilizing reflected emitted beams to influence navigation, for example by ensuring that a reflection is obtained from an encountered surface that is inclined with respect to a surface on which the autonomous device is traveling. In certain embodiments, the present teachings relate more specifically to providing a surface configured to facilitate refection of emissions at an angle that allows proper operation of a cliff sensor of an autonomous device such as a robotic cleaning device encountering a surface that is inclined with respect to a surface on which the autonomous device is traveling.
BACKGROUND
[0003] Many autonomous devices that move around an area in a random or planned coverage path include navigation sensors such as cliff sensors that prevent the device from driving over a ledge such as, for example, stairs. A known cliff sensor and its method of operating are disclosed in U.S. Pat. No. 6,594,844, the entire disclosure of which is incorporated herein by reference. A schematic diagram of an exemplary cliff sensor is illustrated in FIG. 1 . Many known cliff sensors include an infrared light emitting diode (IR-LED) emitter E that emits a beam from a bottom surface of the device onto the surface over which the device travels, most commonly at a predetermined angle. In turn, the surface can reflect or scatter the light upward, and the light can be fanned out over many three-dimensional angles, but with a high concentration of energy in the beam angle that is equal in size, but opposite in sign, to the IR-LED's angle of emission. A companion detector D (also referred to herein as a receiver), such as a photo-transistor that can be oriented to receive reflections from the illuminated zone, is provided to detect a portion of the scattered energy and send information regarding detected energy (e.g., the existence of the detected energy) to the device's controller to let the controller know that a cliff is not imminent. If no reflection is detected by the receiver, the controller can conclude that there is no surface over which to reflect and thus over which to travel, and can then halt or back away from the threat of falling.
[0004] Certain cliff sensors in autonomous devices direct the IR-LED beam onto the surface at an angle of, for example, about 20° to 30° from the vertical, and the receiver can be aimed at the intended illuminated spot at a slightly different angle, with both angles being in a common plane. An exemplary embodiment of a cliff sensor on a robotic cleaning device detecting the presence of a floor under the device is illustrated in FIG. 2A . One skilled in the art will understand that emitted light will be scattered to a greater extent in more reflective surfaces, despite the simplified illustration of FIG. 2A .
[0005] Because the cliff sensor works on the notion that a “cliff’ exists when no reflection of the IR-LED beam is received, there can be occasions when no cliff exists, but the environment, surface composition, or surface geometry interferes with reflection of the IR-LED beam back to the receiver, causing false detection of a cliff and inappropriate halting or reversing of the autonomous device. The environment can effect cliff sensor operation when it contains too much ambient light. Surface composition that can interfere with proper cliff sensing includes dark or black carpeting, which absorbs light and thereby can prevent sufficient reflection of light back to the cliff sensor. One example of a surface geometry that interferes with reflection of the IR-LED beam back to the receiver includes certain 30°-60° surfaces encountered by the cliff sensor, particularly when the surface is highly reflective and thus scatters emitted light such that light is not concentrated at the cliff sensor detector to a suitable degree. While such inclined surfaces may not always interfere with accurate cliff sensor detection, they have the potential to interfere therewith.
[0006] An exemplary embodiment of a cliff sensor on a robotic cleaning device failing to detect the presence of an inclined surface in front of the device is illustrated in FIG. 2B . As can be seen, the surface in FIG. 2B is inclined at an angle of about 45° with respect to the horizontal. As can be seen, because the beam angle is emitted at, for example 20°, the beams therein are reflected from the inclined surface such that they are not detected by the detector. Thus, the controller may inappropriately halt or reverse the device, believing that a cliff exists. Further, the shinier (more reflective) the inclined surface is, the more the emitted beam is scattered and the less likely it is that the detector will receive enough emitted beam to properly move forward over the surface. An example of a shiny, inclined surface that can be encountered by a floor cleaning robot is a threshold or transition plate, as commonly used to transition between different types of flooring. One skilled in the art will understand that emitted light will be scattered to a greater extent in more reflective surfaces, despite the simplified illustration of FIG. 2B .
[0007] Docking stations are known to be used for, e.g., guiding, receiving, and/or charging autonomous devices such as robotic cleaning devices. Docking stations typically provide charging contacts to which contacts on the autonomous device connect so that a power source (e.g., a battery) on the autonomous device can be recharged. Docking stations commonly rest on the floor and provide the charging contact on a raised surface, as shown on FIG. 3 .
[0008] Docking station design, for example combining aesthetic considerations with functional requirements, may dictate that certain surfaces such as exterior walls supporting the raised surface be inclined at an angle of between 30° to 60° which, as stated above, can cause inappropriate halting and/or reversing of the autonomous device, particularly if such inclined surfaces are highly reflective.
SUMMARY
[0009] The present teachings provide a device for controlling the reflection of incident beams to influence navigation of an autonomous device having a navigation sensor comprising a beam emitter and a beam detector for detecting reflected emitted beams. The device comprises at least one surface having a geometry configured to direct a reflection from the emitted beam in a predetermined direction so that a suitable amount of the reflected beam can be detected by the detector.
[0010] The present teachings also provide a device for controlling the reflection of incident beams to influence navigation of an autonomous device having a navigation sensor comprising a beam emitter and a beam detector for detecting reflected emitted beams. The device comprises at least one surface extending generally in a first plane and having a geometry comprising sub-surfaces extending in different planes than the first plane and directing a reflection from the emitted beam toward the beam detector.
[0011] The present teachings further provide a docking station having at least one inclined, reflective surface configured to control the reflection of incident beams, the surface influencing navigation of a robotic cleaning device having a navigation sensor comprising a beam emitter and a beam detector for detecting reflected emitted beams. The at least one inclined, reflective surface has a geometry configured to direct a reflection from the emitted beam in a predetermined direction so that a suitable amount of the reflected beam can be detected by the detector.
[0012] Additional objects and advantages of the present teachings will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present teachings. The objects and advantages of the present teachings will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
[0013] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present teachings, as claimed.
[0014] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the present teachings and, together with the description, serve to explain the principles thereof.
DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a schematic diagram of an exemplary known cliff sensor.
[0016] FIG. 2A illustrates an exemplary embodiment of a cliff sensor on a robotic cleaning device detecting the presence of a floor under the device.
[0017] FIG. 2B illustrates an exemplary embodiment of a cliff sensor on a robotic cleaning device failing to detect the presence of an inclined surface in front of the device.
[0018] FIG. 2C illustrates an exemplary embodiment of a cliff sensor on a robotic cleaning device detecting the presence of an inclined surface in front of the device.
[0019] FIG. 3 illustrates an exemplary embodiment of a known autonomous device docking station.
[0020] FIG. 4 illustrates an exemplary embodiment of a known autonomous device docking station having a surface geometry in accordance with the present teachings.
[0021] FIG. 5 is a detailed view of the surface geometry utilized in the docking station of FIG. 4 .
[0022] FIG. 6 illustrates an exemplary rear side area of the base station.
[0023] FIG. 7 illustrates an exemplary rear area of the base station.
[0024] FIG. 8 is a schematic diagram of a cross section of an exemplary embodiment of a surface geometry in accordance with the present teachings.
[0025] FIG. 9 is a schematic diagram illustrating an embodiment of a surface geometry that can be used to cause reflection of emitted beams away from a detector to prevent an autonomous device having a cliff or similar sensor from advancing to a given area.
[0026] Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0027] Reference will now be made in detail to various exemplary embodiments of the present teachings, one or more of which are illustrated in the accompanying drawings.
[0028] As autonomous devices such as robotic cleaning devices navigate an area such as a floor to be cleaned, their path can be substantially randomly generated and controlled by input from various sensors on the autonomous device such as, for example, cliff sensors. The cliff sensor's primary purpose is to prevent the autonomous device from driving off of a “cliff.” The cliff sensor can also be utilized, however, to control navigation of the autonomous device when reflection or the direction of a reflection of a beam emitted from the cliff sensor is controlled to influence navigational behavior of the vehicle. This can be done, for example, by (1) preventing proper reflection of the emitted cliff sensor beam to the cliff sensor detector to keep the autonomous device from entering an area, or by (2) causing reflection of the emitted cliff sensor beam to the cliff sensor detector to prevent inappropriate stopping and reversing of the autonomous device.
[0029] As shown in FIG. 3 , autonomous device docking stations can comprise a base plate and a substantially vertical backstop, and can include one or more docking signal emitters and one or more LEDs. The base plate can include one or more raised surfaces on which one or more charging contacts are provided and appropriately positioned to mate with contacts on the autonomous device. The raised surfaces can be supported by exterior walls that are inclined. In the illustrated exemplary docking station embodiment, two raised surfaces of the base plate extend forwardly from the substantially vertical backstop in a generally parallel arrangement, and a recessed area of the base plate extends between the two raised surfaces. The recessed area can accommodate structure on an underside of the autonomous device when it is docking or docked. In the embodiment illustrated in FIG. 3 , the exterior walls of the base plate are inclined at an angle of between 30°-60°.
[0030] Many autonomous vehicles, such as robotic cleaning devices, are powered by a rechargeable power source such as a battery. When an autonomous device's battery needs to be recharged, the autonomous device typically begins the process of trying to locate and navigate to a docking station that can recharge its battery. The autonomous device may also return to the docking station when it is done performing its tasks. An exemplary process of locating and navigating to a docking station is described in U.S. patent application Ser. No. 11/633,869, filed Dec. 4, 2006, for an Autonomous Coverage Robot Navigation System, the entire content of which is incorporated herein by reference.
[0031] In an exemplary docking process, a base station emits an omnidirectional beam that is projected laterally around the docking station. In addition, navigational field emitters emit signal beams having laterally bounded and overlapping fields of emission. When the autonomous device enters a docking mode and detects, for example, the base station omni-directional beam and begins moving toward a base station, the remote vehicle can detect and follow a lateral field edge defined by one or more of the navigational field emitter signal beams, the lateral field edge being aligned with a proper docking direction. The autonomous device maneuvers toward the base station by detecting and advancing along the lateral field edge until it encounters the docking station. In certain embodiments, the autonomous device can servo along the lateral field edge.
[0032] In certain instances, when an autonomous device is attempting to dock with a docking station having an inclined reflective exterior wall such as that illustrated in FIG. 3 , the cliff sensor of the autonomous device may not detect a beam reflected from the inclined surface for the reasons explained above. In such a case, the autonomous device may inappropriately conclude that a cliff exists. If the device then halts or reverses, it may not be able to properly dock and recharge its battery as needed.
[0033] The autonomous device may also pass close to docking station even when not trying to dock, and may be inappropriately halted by any reflective inclined wall thereof. Further, other inclined surfaces may exist in the environment in which the autonomous device navigates, and those surfaces may similarly interfere with autonomous device navigation.
[0034] Providing a surface having a geometry allowing the autonomous device to reliably detect surfaces having an incline of 30° to 60° from the horizontal can increase overall performance and reliability of the autonomous device. FIGS. 4-7 illustrate a docking station 100 having inclined walls and utilizing an exemplary geometry allowing a robotic cleaning device to reliably detect its presence and successfully dock. The illustrated exemplary docking station 100 includes a substantially vertical backstop 110 having a top surface 120 . One skilled in the art will readily understand that the backstop can have a variety of shapes and sizes depending on a variety of aesthetic and functional limitations and considerations.
[0035] An emitter 130 , such as an omni-directional emitter, can be located on the top surface 120 of the backstop 110 , along with an LED 140 . The emitter can facilitate docking of an autonomous cleaning device, for example in accordance with the description above. The LED can indicate, for example, when the docking station 100 has power. A front surface 150 of the backstop 110 can include one or more additional emitters 160 , such as navigational field emitters, which can facilitate, for example, docking of an autonomous cleaning device, for example in accordance with the description above.
[0036] The exemplary docking station illustrated in FIG. 4 additionally includes, rather than a unitary base plate as illustrated in FIG. 3 , two separate forwardly extending legs 200 with an opening 220 therebetween. Each forwardly-extending leg 200 can be sized and shaped to properly position a charging contact 210 for mating with charging contacts on an associated autonomous cleaning robot. In the embodiment illustrated in FIG. 4 , the forwardly-extending legs 200 provide charging contacts 210 on respective raised top surfaces 205 . Inclined walls, 230 , 240 , and 250 extend upwardly to the top surface 205 of the legs 200 . An additional surface 260 , extending downwardly from the backstop, may or may not be inclined. The inclined walls 230 , 240 , and 250 include interior side walls 230 , front walls 240 , and exterior side walls 250 . In the illustrated embodiment, the inclined walls 230 , 240 , and 250 have a surface geometry allowing an autonomous cleaning robot to reliably detect, via its cliff sensor, the inclined walls 230 , 240 , and 250 . The additional surface 260 may also have a geometry allowing an autonomous cleaning robot's cliff sensor to reliably detect it. In the illustrated embodiment, the geometry comprises a series of steps. Each step can comprise, for example, a vertical surface V and a horizontal surface H (see FIG. 5 ). The steps need not comprise portions that are exactly horizontal and exactly vertical. The angle of the surfaces comprising the steps can be adjusted to control the desired reflection path of light from the stepped surface.
[0037] FIG. 2C is a schematic diagram of a cliff sensor on a robotic cleaning device detecting the presence of an encountered inclined surface having an exemplary surface geometry in accordance with the present teachings. As can be seen, the surface in FIG. 2C is generally at an angle of about 45° with respect to the horizontal, with the steps extending in substantially vertical and substantially horizontal planes. The emitted beams are reflected from the stepped surface toward the detector. Thus, the cliff detector should determine that no cliff exists and the robotic cleaning device can move forward. One skilled in the art will understand that emitted light will be scattered to a greater extent in more reflective surfaces, despite the simplified illustration of FIG. 2C .
[0038] FIG. 6 illustrates an exemplary rear side area of the base station 100 , where the leg 200 meets the back stop 100 . As can be seen, in this exemplary rear side area, the stepped geometry of the exterior side wall 250 can end at a transition area 255 to a section having an alternative geometry 270 . In this illustrated embodiment, the alternative embodiment includes a bumpy, textured surface. Such a surface can allow, as illustrated in FIG. 6 , information to be displayed and visible on the surface while still improving detection of the surface by a cliff sensor.
[0039] FIG. 7 illustrates an exemplary rear portion of a side of the base station, including an aperture 300 extending through a wall 180 of the rear portion. The aperture can accommodate, for example, a power cord for the base station in a known manner. As can be seen, in the illustrated exemplary embodiment, lower portions 280 , 290 of the rear wall can also be inclined, for example for aesthetic reasons. These inclined lower portions 280 , 290 could conceivably come into contact with the cleaning robot's cliff sensor and can thus comprise a stepped or otherwise textured inclined surface in accordance with the present teachings to avoid false readings by the cleaning robot's cliff sensor.
[0040] FIG. 8 is a schematic diagram of a cross section of an exemplary embodiment of a surface geometry in accordance with the present teachings, such as the stepped surface illustrated in FIGS. 5-7 . As shown, the surface S 1 extends generally in a first plane P and has a geometry comprising sub-surfaces V and H extending in different planes, Pv and PH respectively, than the first plane P to direct a reflection from the emitted beam toward the beam detector. One skilled in the art will understand that the sub-surfaces need not be exactly vertical or horizontal, and the angles thereof can be modified to alter the control the location to which the beam reflections are directed. In the illustrated schematic, the plane P of surface 81 is inclined at an angle a with respect to a surface 82 over which an autonomous device would be traveling prior to encountering the surface 81 .
[0041] The present teachings contemplate other embodiments having surface geometries that are not stepped, but which control reflection of emitted beams to redirect the emitted beam reflections. On such alterative embodiment comprises the textured surface geometry illustrated in section 270 of the illustrated base station. Such a surface geometry could be used over all of the discussed inclined surfaces of the docking station to improve cliff sensor detection of the docking station. In addition, the present teachings contemplate use of surface geometries for controlling reflection direction on elements other than a docking station. For example, such a surface geometry could be used on a threshold or transition plate, as commonly used to transition between different types of flooring, or on a ramped surface, for example transitioning between surfaces at different levels over which the autonomous device must navigate to get from one level to another.
[0042] Further, a surface geometry used in accordance with the present teachings can also be used to cause reflection of emitted beams away from a detector, for example to prevent an autonomous device having a cliff or similar sensor from advancing to a given area. For example, the present teachings contemplate using a surface geometry directing emitted beams away from a detector to prevent passage of an autonomous device into a bounded area such as a room. In one exemplary embodiment, a strip of material having such a surface geometry could be placed on the floor of a doorway to prevent the autonomous device from passing through the doorway. FIG. 9 is a schematic diagram illustrating an embodiment of a surface geometry that can be used to cause reflection of emitted beams away from a detector to prevent an autonomous device having a cliff or similar sensor from advancing to a given area. The area denoted “STEP ANGLE B” can cause such a deflection. In the embodiment illustrated in FIG. 9 , the surface geometry can be used to turn the signal on, off, and on, as shown.
[0043] Other embodiments of the present teachings will be apparent to those skilled in the art from consideration of the specification and practice of the teachings disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the present teachings being indicated by the following claims. | A device for controlling the reflection of incident beams to influence navigation of an autonomous device having a navigation sensor comprising a beam emitter and a beam detector for detecting reflected emitted beams. The device comprises at least one surface having a geometry configured to direct a reflection from the emitted beam in a predetermined direction so that a suitable amount of the reflected beam can be detected by the detector. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to window shades. More specifically, the present invention relates to spring tension mounted window shades.
[0003] 2. Background of the Related Art
[0004] In the home improvement and construction industries, there is a desire to make a window more pleasing to the eye, to provide some type of shade to the sun and to provide privacy, as needed. Windows are available in many different sizes thereby necessitating that the window shade be fit to the window casement at hand. As a result, numerous sizes of window shades must be available to fit a given window. This is particularly problematic in connection with the sale of such shades because different sizes of shades must be available for purchase to fit the different sizes of windows. Windows of uncommon sizes require custom built shades.
[0005] In the prior art, there have been many attempts to address the problem of fitting a shade to a window. U.S. Pat. No. 473,990 (Wilkinson) provides such a spring tension shade that includes spring-loaded pads on opposing ends of the shade to frictionally grip the facing sides of a window casement. However, the main body must generally fit within the width of the casement thereby. This device is not intended to fit to a wide range of window sizes. The focus of this invention is simply to removably attach a window shade to a window casement without the use of tools or mounting hardware. U.S. Pat. No. 4,373,569, issued to Barretella, similarly provides for a window shade assembly that can be easily installed and which is held in place by friction.
[0006] These prior art assemblies, however, suffer from the disadvantage of being of a substantially fixed length. The play in the spring-biased pads on the opposing ends of the assembly is minimal. As a result, the prior art assemblies are specifically made for installation into a specific sized window casement.
[0007] Therefore, there is a desire to provide a single spring tension shade assembly that can be installed into windows of a wide range of sizes. There is a desire to provide to the consumer with a single shade assembly that can be easily adjusted to fit a given window
[0008] Another disadvantage of prior art shade rollers is that the holding force exerted by the ends of the assembly is through the roller itself. This means that there is increased friction that keeps the roller from turning freely. As the holding force increases, the force necessary to operate the roller thereby increases making it harder to furl or unfurl the shade. The increase in the force necessary to operate the shade necessitates that the holding force must be increased to keep the shade assembly secure within the window casement.
[0009] Therefore, there is a need for a tension shade assembly that minimizes or reduces the forces exerted on the roller itself to prevent the jamming or the rotation of the roller or the dislodgment of the tension shade assembly from the window casement.
SUMMARY OF THE INVENTION
[0010] The present invention solves the problems associated with the prior art shade assemblies. The adjustable tension shade of the present invention includes a shade roller having a tubular body and a telescoping spring-biased axle. The shade roller has a first portion that slidably resides within a second portion to form the shade roller. The axle has a axle body portion and an adjustment rod portion that is received therein. The axle body portion has an adjustment spring contained therein. The adjustment rod portion has a raised shoulder that cooperates with the adjustment spring contained in the axle body portion to position the adjustment rod therein. The adjustment spring urges the free ends of the axle away from each other. As a result, the axle body member can be retained within a window casement by friction in similar fashion to a standard spring tension curtain rod. The ends of the axle have cushioned footings attached thereon to retain the entire assembly in place without damaging the window casement walls.
[0011] Unlike a curtain rod, the second (outer) portion of the tubular body member is also fitted with a spring motor. Thus, a shade can be attached thereto so it can be rolled in similar fashion to a typical spring tension shade, such as that depicted in the Wilkinson '990 patent discussed above.
[0012] However, the shade assembly of the present invention can be adjusted in width across a wide range to accommodate window casements of different sizes. The shade assembly is fit to a given window and then the shade itself is selected to fit to the adjusted to length. The shade member can be cut to the size and then attached directly onto the second (outer) tubular member so that it can be wound thereabout, as desired. However, it is also possible to provide a window shade member that can be sized by the user without cumbersome cutting. As seen in U.S. Pat. No. 4,438,799, issued to Comeau and commonly owned with the instant invention, a shade of adjustable width, using tear-way strips, can be used in conjunction with the present invention to facilitate the sizing of the shade member. Using the easy-adjusting shade member of Comeau '799, the shade assembly can be provided in a single kit for a consumer to custom install and fit a shade assembly into a wide range of window casement sizes.
[0013] Accordingly, it is an object of the present invention to provide an adjustable tension shade rod that can be easily adjusted to fit a range of window sizes.
[0014] Another object of the present invention is the provision for an adjustable tension shade rod that can be mounted to a window casement without the need for special mounting hardware.
[0015] Yet another object of the present invention is the provision for an adjustable tension shade that can be mounted to a window casement without damaging the window casement.
[0016] Yet another object of the present invention is the provision for an adjustable tension shade that minimizes the lateral forces on the roller of the tension shade thereby preventing jamming or dislodgment of the tension shade from the window casement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawings where:
[0018] FIG. 1 is a perspective view of the preferred embodiment of the tension shade assembly of the present invention;
[0019] FIG. 2 is a perspective view of the preferred embodiment of the tension shade assembly of the present invention with the shade member removed;
[0020] FIG. 3 is a exploded view of the preferred embodiment of the tension shade assembly of the present invention;
[0021] FIG. 4 is a side cross-section view through line 1 - 1 of FIG. 1 ;
[0022] FIG. 5 is a close-up side cross-section view of the adjustable end of the preferred embodiment shown in FIG. 4 ;
[0023] FIG. 6 is a close-up side cross-section view of the middle portion of the preferred embodiment shown in FIG. 4 ; and
[0024] FIG. 7 is a close-up side cross-section view of the spring-motor end of the preferred embodiment shown in FIG. 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] The adjustable tension shade rod of the present invention is shown generally at 10 in FIGS. 1-7 . As will hereinafter be more fully described, the present invention provides an inexpensive adjustable tension shade rod that can be adjusted to fit many windows of varying dimensions without the need for additional mounting hardware and without damaging the window casement walls.
[0026] Referring first to FIG. 1 , a front perspective view of the spring tension rod assembly 10 of the present invention is shown to include a telescoping shade roller 26 with a foot 28 on each opposing sides thereof. As will be described in detail below, the shade roller 26 is rotatably mounted relative to each foot 28 . A grip surface 30 is provided on the ends of each foot 28 is a grip surface for communicating with a mount surface, such as a window casement. A shade 33 is wound about the shade roller 26 . FIG. 1 illustrate the shade 33 fully would about the shade roller 26 .
[0027] Turning now to FIG. 2 , the spring tension rod assembly of FIG. 1 is shown without shade 33 for ease of discussion. As will be described in detail below, first portion 32 and second portion 34 of shade roller telescope relative to one another while still being able to carry shade 33 , as seen in FIG. 1 . Thus, as seen in FIG. 4 , the spring tension shade assembly 10 can be easily compressed laterally so that it may clear past the sides of a window casement, then positioned as desired and then released so it may be frictionally, yet removably, retained in place.
[0028] Turning now to FIG. 3-7 further details of the invention are set forth. The adjustable tension shade assembly 10 of the present invention has an axle 12 that has an adjustable telescoping shaft. The axle 12 includes an axle body portion 14 and an adjustment rod portion 16 . The axle body portion 14 is preferably an open seam roll-formed tube, but other construction techniques could be used. The axle body portion 14 has an adjustment spring 18 contained therein that extends the length of the axle body portion 14 . The adjustment spring 18 is retained within the axle body portion 14 by selectively crimping the axle body portion 18 , but other techniques could be used equally effectively. The adjustment rod portion 16 includes a raised shoulder 20 on one end, which can best be seen in FIG. 6 . The raised shoulder 20 can be formed, preferably of metal, by a number of methods that one skilled in the art would appreciate, including stamping, integrally molding or turning upwardly one end of the adjustment rod portion 16 among others. Other materials and manufacturing techniques may be used for the adjustment rod portion 16 . Most preferably, the raised shoulder 20 is formed by stamping the adjustment rod portion 16 near one end, leaving a small portion 22 extending beyond the raised shoulder 20 .
[0029] As seen in FIG. 6 , the adjustment rod portion 16 is slidably received into the axle body portion 14 and threaded into the adjustment spring 18 contained therein. The raised shoulder 20 serves a guide within the coils of the adjustment spring 18 to keep the adjustment rod portion 16 from moving freely within the axle body portion 14 or becoming dislodged entirely. By turning the adjustment rod portion 16 , it can be threaded in or out of the axle body portion 14 to the length that is desired to fit the entire assembly 10 into a particular window casement 21 . The small portion 22 of the adjustment rod portion 16 extending beyond the raised shoulder 20 serves to stabilize the adjustment rod portion 16 within the adjustment spring 18 and axle body portion 14 of the axle 12 and prevents the raised shoulder 20 from jumping the coils of the adjustment spring 18 . The adjustment spring 18 also urges the adjustment rod portion 16 out and away from the axle body portion 14 and thus urges the free ends of the axle 12 away from each other. A metal coil spring is preferably used to spring-bias the axle to an extended telescoped condition. Other spring-biasing structures may be used for this purpose.
[0030] Turning now to FIG. 7 , a spring motor 24 is connected to one end of the axle body portion 14 of the axle 12 and serves to drive the shade roller 26 , described below, during operation of the adjustable tension shade assembly 10 . The axle 12 reamins stationary while the spring motor 24 furls and unfurls the shade 33 on the shade roller 26 . Spring motors 24 are well-known in the art and one skilled in the art would be capable of selecting or constructing an appropriate spring motor 24 to drive the adjustable tension shade assembly 10 of the present invention. Therefore, the spring motor 24 need not be discussed in further detail herein.
[0031] Referring back to FIGS. 1 and 4 , attached to each end of the axle is a foot 28 . Each foot 28 serves to secure the adjustable tension shade assembly 10 against the window casement 21 without the use of additional mounting hardware. Although optional, each foot 28 preferably includes a soft rubber, or rubber-like, grip surface 30 to prevent damage to the underlying wall of the window casement 21 . Each grip surface 30 enhances the friction fit of the adjustable tension shade assembly 10 in the window casement 21 and prevents its slippage therefrom. Optionally, each foot 28 may further be pivotally mounted to the axle 12 to allow the adjustable tension shade assembly 10 to be fit into a window casement 21 that has walls that are not plumb or otherwise have uneven surfaces.
[0032] As best seen in FIGS. 3-6 , received over the axle 12 is a shade roller 26 that has a tubular body. The shade roller 26 includes a first portion 32 and a second portion 34 . The second portion 34 is slidably received into the first portion 32 and enables the shade roller 26 to be adjusted to the desired length of the axle 12 . After the axle 12 has been adjusted to the desired length as described above, the shade roller 26 is extended or retracted as appropriate to correspond to the length of the axle 12 . A shade 33 , shown in FIG. 1 but omitted from the other figures for ease of description, is attached to the shade roller 26 and is furled and deployed as desired.
[0033] Once the tension shade assembly 10 is sized to a given window casement 21 or other mounting structure, the shade 33 of the appropriate width can be secured to the shade roller 26 . As described above, the appropriate width may be achieved by cutting the shade, for example.
[0034] Referring back to FIG. 2 , the shade roller 26 further includes a groove 36 on the first portion 32 that engages a tongue 38 on the second portion 34 . The engagement of the tongue 38 with the groove 36 prevents the rotational movement of either portion 32 , 34 relative to the other. This feature is commonly referred to as “keying.” This keying the portions 32 , 34 of the shade roller 36 prevents the adjustable tension shade assembly 10 from malfunctioning during its operation. As would be appreciated by one skilled in the art, the use of a tongue 38 and a groove 36 are but one implementation that one could use to “key” the portions 32 , 34 of the shade roller 26 together.
[0035] In FIGS. 3 and 4 , an end cap 40 is frictionally fit into the free end of the second portion 34 of the shard roller 26 and serves to support the shade roller 26 on the adjustment rod portion 16 of the axle 12 .
[0036] It can therefore be seen that the present invention provides a simple, yet inexpensive, adjustable tension shade that can be mounted in a variety of window casements and without damaging the window casement or the need for additional hardware. For these reasons, the instant invention is believed to represent a significant advancement in the art that has substantial commercial merit.
[0037] While there is shown and described herein certain specific structure embodying the invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described except insofar as indicated by the scope of the appended claim. | The adjustable tension shade includes a spring motor, an axle, and a shade roller. The spring motor is mounted to the axle and drives the shade roller. The axle has an adjustable telescoping shaft and the free ends of the axle are spring-biased outwardly away from each other. The shade roller has a tubular body that surrounds the axle and the spring motor and serves as a mounting point and storage unit for a shade. A pair of feet is connected to each end of the axle and each has a soft rubber gripping surface thereon. | 4 |
Related Applications
This application is a Continuation of Ser. No. 07/614,037 filed Nov. 19, 1990, now abandoned; which is a Continuation of Ser. No. 07/096,461 filed Sep. 15, 1987, now abandoned; which is a Continuation-in-Part of Ser. No. 06/730,596 filed May 6, 1985, now U.S. Pat. No. 4,855,860; which is a Continuation-in-Part of Ser. No. 06/640,240 filed Aug. 13, 1984, now U.S. Pat. No. 4,563,719; which is a Continuation of Ser. No. 06/412,771, filed Aug. 30, 1982, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to inverter-type electronic ballasts for gas discharge lamps, particularly of the type wherein a gas discharge lamp is connected with the inverter's output by way of a series-excited parallel-loaded resonant L-C circuit.
2. Description of Prior Art
Inverter-type electronic ballasts for gas discharge lamps of the type wherein the inverter output is connected with the gas discharge lamp by way of a series-excited parallel-loaded resonant L-C circuit are fundamentally cost-effective and energy-efficient. Such ballasts are described in prior art, such as in U.S. Pat. Nos. 4,461,980, 4,581,562 and 4,663,571 to Nilssen.
However, a very basic problem associated with such series-resonance-loaded inverter-type ballasts is that of the likelyhood of self-destruction in the event that the lamp is removed or otherwise fails to constitute a proper load on the series-resonant L-C circuit.
The prior art has dealt with that problem in various ways; and the issue now is basically that of finding a still more cost-effective way of so doing.
SUMMARY OF THE INVENTION
Objects of the Invention
An object of the present invention is that of providing an energy-efficient cost-effective inverter-type electronic ballast for gas discharge lamps.
More specifically, an object is that of providing an energy-efficient cost-effective inverter-type ballast of a type wherein the inverter is powering a gas discharge lamp by way of a series-excited parallel-loaded resonant L-C circuit.
This as well as other objects, features and advantages of the present invention will become apparent from the following description and claims.
BRIEF DESCRIPTION
In its preferred embodiment, subject invention constitutes a series-excited parallel-loaded fluorescent lamp ballast comprising the following key component parts:
a source of DC voltage, which DC voltage is derived by rectification of the AC voltage from a regular 60 Hz power line;
an inverter connected with the source of DC voltage and operative to provide across an output a high-frequency square-wave voltage, the inverter having control input means operative in response to a control signal to control the frequency of the squarewave voltage between a minimum frequency and a maximum frequency;
an L-C circuit series-connected across the output, the L-C circuit having: i) a main tank-capacitor, ii) a main tank-inductor, and iii) a natural resonance frequency equal to the fundamental frequency of the squarewave voltage at its minimum frequency;
a pair of auxiliary tank-inductors, each magnetically coupled to the main tank-inductor and connected by way of an auxiliary capacitor to a pair of cathode power output terminals, each auxiliary tank-inductor being series-resonant with its auxiliary tank-capacitor at the fundamental frequency of the squarewave voltage at its maximum frequency;
a fluorescent lamp having a pair of main lamp power input terminals and two pairs of cathode power input terminals;
connect means operative to connect: i) the main lamp power input terminals across the tank-capacitor, and ii) each pair of cathode power input terminals with one of the pairs of cathode power output terminals; and
control means: i) responsive to lamp current flowing through the fluorescent lamp, ii) connected with the control input means, and iii) operative to provide the control signal in such manner as to increase the frequency of the squarewave voltage in response to the flow of lamp current;
whereby:
a) the inverter is protected from self-destruction by making the frequency of the squarewave voltage substantially higher than the L-C circuit's natural resonance frequency whenever the L-C circuit is inadequately loaded, as signified by absence of lamp current; and
b) the amount of cathode heating power is reduced as the magnitude of lamp current is increased, thereby improving overall operating efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically illustrates the preferred embodiment of the invention.
FIG. 2 illustrates a modified version of the preferred embodiment.
FIG. 3 shows various voltage and current waveforms associated with the preferred embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Details of Construction
In FIG. 1, a source S of 120 Volt/60 Hz voltage is applied to a full-wave bridge rectifier BR, the unidirectional voltage output of which is applied directly between a B+ bus and a B+ bus, with the positive voltage being connected to the B+ bus.
Between the B+ bus and the B- bus are connected a series-combination of two transistors Q1 and Q2 as well as a series-combination of two energy-storing capacitors C1 and C2.
A secondary winding CT1s of positive feedback current transformer CT1 is connected directly between the base and the emitter of transistor Q1; a secondary winding CT2s of positive feedback current transformer CT2 is connected directly between the base and the emitter of transistor Q2.
The collector of transistor Q1 is connected directly with the B+ bus; the emitter of transistor Q2 is connected directly with the B- bus; and the emitter of transistor Q1 is connected directly with the collector of transistor Q2, thereby forming junction QJ.
One terminal of capacitor C1 is connected directly with the B+ bus, while the other terminal of capacitor C1 is connected with a junction CJ. One terminal of capacitor C2 is connected directly with the B- bus, while the other terminal of capacitor C2 is connected directly with junction CJ.
An inductor L and a capacitor C are connected in series with one another and with primary windings CT1p and CT2p of current transformers CT1 and CT2.
The series-connected primary windings CT1p and CT2p are connected directly between junction QJ and a point X. Inductor L is connected with one of its terminals to point X and with the other of its terminals to another point Y; and capacitor C is connected between point Y and junction CJ.
A first auxiliary inductor AL1 is coupled loosely with tank-inductor L and is connected in series with a first auxiliary capacitor AC1 and a first thermionic cathode TC1 of a fluorescent lamp FL; a second auxiliary inductor AL2 is also coupled loosely with tank-inductor L and is connected in series with a second auxiliary capacitor AC2 and a second thermionic cathode TC2 of fluorescent lamp FL.
One of the terminals of thermionic cathode TC2 is connected by way of a primary winding CT3p of a current transformer CT3 to junction CJ; one of the terminals of thermionic cathode TC1 is connected with point Y. A secondary winding CT3s has two terminals and a center-tap; which center-tap is connected with the B- bus.
Current transformer CT1 has a tertiary winding CT1t connected between the B- bus and the anode of a diode D1; the cathode of diode D1 is connected with the cathode of a diode D2, whose anode is connected with one of the terminals of a tertiary winding CT2t of current transformer CT2. The other terminal of tertiary winding CT2t is connected with the B- bus.
A field effect transistor FET is connected with its drain terminal to the cathodes of diodes D1 and D2 and with its source terminal to the B- bus. An adjustable resistor AR is connected between the drain and source terminals. The gate terminal of transistor FET is connected with the B+ bus by way of a resistor R1 and with the B- bus by way of a resistor R2.
A control transistor CT is connected with its collector to the gate of transistor FET and with its emitter to the B- bus. Its base is connected by way of a resistor R3 to the cathode of a diode D3, whose anode is connected with one of the terminals of secondary winding CT3s of current transformer CT3. A diode D4 is connected with its anode to the other terminal of secondary winding CT3s and with its cathode to the cathode of diode D3.
A filter capacitor FC and a resistor R4 are both connected between the cathodes of diodes D3/D4 and the B- bus.
A resistor R5 is connected between the B+ bus and the anode of a diode D5, whose cathode is connected with junction QJ. A Diac D6 is connected between the anode of diode D5 and the base of transistor Q2. A capacitor C4 is connected between the anode of diode D5 and the B- bus.
FIG. 2 is identical to FIG. 1 except for having: a Varistor V connected between junction CJ and point Y; a resistor R6 connected between the B+ bus and a junction J; a capacitor C5 connected between junction J and the B- bus; and a Diac D7 and a resistor R7 series-connected between junction J and the base of control transistor CT.
DETAILS OF OPERATION
In FIG. 1, source S represents an ordinary electric utility power line, the voltage from which is applied directly to the bridge rectifier identified as BR. This bridge rectifier is of conventional construction and provides for the rectified line voltage to be applied to the inverter circuit by way of the B+ bus and the B- bus.
The two energy-storing capacitors C1 and C2 are connected directly across the output of the bridge rectifier BR and serve to filter the rectified line voltage, thereby providing for the voltage between the B+ bus and the B- bus to be substantially constant in magnitude. Junction CJ between the two capacitors serves to provide a power supply center tap.
The inverter circuit of FIG. 1, which represents a so-called half-bridge inverter, operates in a manner that is analogous with circuits previously described in published literature, as for instance in U.S. Pat. No. 4,184,128 entitled High Efficiency Push-Pull Inverters.
Inverter oscillation is initiated by one or a few trigger pulses applied to the base of transistor Q2 by way of the combination of resistor R5, capacitor C4 and Diac D6. Once the inverter starts operating, the provision of trigger pulses ceases because diode D5 then prevents capacitor C4 from reaching a voltage high enough to cause Diac D6 to break down.
The output of the half-bridge inverter is a substantially squarewave AC voltage provided between point X and junction CJ. By controlling the degree by which the saturable feedback current transformers CT1/CT2 are re-set after each time they have been operative to supply base current to their respective transistors Q1/Q2, the frequency of this squarewave AC voltage can be controlled between about 30 kHz and 60 kHz.
The degree to which the saturable feedback current transformers are re-set is determined by the magnitude of the voltage presented to the tertiary windings CT1t/CT2t during the re-set period. By controlling the magnitude of this voltage, the degree of re-set is controlled correspondingly: the lower the magnitude of the voltage present across the tertiary windings during the re-set period, the lower the degree of re-set of the saturable magnetic cores of feedback transformers CT1/CT2.
And, the lower the degree of re-set, the shorter will be the duration of the periods where the feedback transformers provide drive current to the bases of transistors Q1/Q2, and the higher will be the frequency of the squarewave AC voltage.
FIG. 3 illustrates the situation.
FIG. 3a depicts the collector-emitter voltage Vcel of transistor Q2 during a first situation where the magnitude of the voltage across the tertiary windings of saturable feedback transformers CT1/CT2 is prevented from exceeding a relatively low level--as indicated in FIG. 3b, which depicts the corresponding base-emitter voltage Vbel.
FIG. 3c depicts the collector-emitter voltage Vce2 of transistor Q2 during a second situation where the magnitude of the voltage presented to the tertiary windings of saturable feedback transformers CT1/CT2 is permitted to reach a relatively high level--as indicated in FIG. 3d, which depicts the corresponding base-emitter voltage Vbe2.
The frequency of inverter operation prevailing during the first situation is about twice that prevailing during the second situation (60 kHz or so versus 30 kHz or so).
Saturable feedback transformers CT1 and CT2 are both current transformers; which means that the magnitude of the voltage developing across a secondary or tertiary winding is a function of the magnitude of the associated primary current as multiplied by the turns-ratio and affected by the impedance characteristics of the load presented to this secondary or tertiary winding.
In particular, when transistor FET is fully conductive (i.e, acting like a short circuit)--which is the state it does indeed assume as long as no current flows through the fluorescent lamp (FL)--each of tertiary windings CT1t/CT2t is loaded with a forward-conducting diode during the re-set periods, while each of secondary windings CT1s/CT2s is loaded with a forward-conducting base-emitter junction during the drive periods. In other words, both the tertiary and the secondary windings are then loaded with a single forward-conducting diode junction.
However, the tertiary windings have about three times as many turns as do the secondary windings; which implies that the forward voltage drops presented by diodes D1/D2 to the tertiary windings have substantially less effect (per unit time) in terms of re-setting the magnetic cores of transformers CT1/CT2 than do the forward voltage drops presented to the secondary windings by the base-emitter junctions of transistors Q1/Q2 have in terms of setting the magnetic cores.
As a consequence of positive feedback, each transistor receive base current until its associated saturable feedback transformer reaches saturation; and the length of time it takes for this saturation to occur is proportional to the degree by which the magnetic core of the saturable feedback transformer has been reset.
FIGS. 3a and 3c also indicate the collector currents Ic1 and Ic2 flowing through transistor Q2 in correlation with collector-emitter voltages Vce1 and Vce2 and base-emitter voltages Vbe1 and Vbe2, all respectively.
When transistor FET is conducting, the situation of FIGS. 3a and 3b prevails; when transistor FET is non-conducting, the situation of FIGS. 3c and 3d prevails.
The conditions prevailing when transistor FET is nonconducting can be adjusted by adjustable resistor AR; which means that the lower inverter frequency can be adjusted by adjusting adjustable resistor AR.
The loosely coupled auxiliary inductors AL1 and AL2 are each tuned to series-resonate with auxiliary capacitors AC1 and AC2, respectively, at the higher inverter frequency; which means that, when the inverter frequency changes to the lower frequency, the amount of power provided to the cathodes will diminish significantly. The degree of diminishment can be chosen by way of choosing the loaded (operating) Q of the series-resonant circuits consisting of AL1/AC1 and AL2/AC2.
In the arrangement of FIG. 1, in the initial mode of the ballast, when the inverter oscillates at its higher frequency, the magnitude of the voltage present across tank-capacitor C is so arranged as to be just adequate to cause lamp current to start flowing after the cathodes have become thermionic. Then, as soon as some lamp current is flowing, current will be provided to the base of control transistor CT; which will then act to cause transistor FET to change to its non-conductive state, thereby causing the inverter to reduce its frequency to the lower frequency, which will then increase lamp current to its proper operational level.
If the lamp is non-connected, or if the lamp otherwise fails to conduct current, the ballast will remain in its initial mode of oscillating at the higher frequency.
In the arrangement of FIG. 2, the initial higher-frequency inverter mode is such as to provide proper cathode heating, but inadequately high voltage across the tank-capacitor to cause any significant amount of the current to flow through the lamp. Instead, to get the lamp ignited, after the initial mode has existed for about one second, a pulse is provided to the base of control transistor CT; which pulse is arranged to last for about 5 milli-seconds, thereby causing transistor FET to become non-conductive for a period of about 5 milli-seconds; which means that the inverter will oscillate at its lower frequency for that length of time.
After the cathodes have been pre-heated for about one second (or 1000 milli-seconds), the lamps are ready to ignite; and they then do indeed ignite within the 5 milli-second period during which the inverter oscillates at its lower frequency--this being so for the reason that the high-Q L-C circuit (which consists of tank-inductor L and tank-capacitor C) is resonant at or near this lower frequency; which means, due to so-called Q-multiplication, that the magnitude of the voltage developing across the tank-capacitor will increase until limited by whatever load is present thereacross.
After the lamps ignite (i.e., as soon as lamp current starts flowing), by means of lamp current sensing transformer CT3, control current will be provided to the base of control transistor CT, which will then assure that the inverter will remain in its position of oscillating at the lower frequency as long as lamp current is indeed flowing.
However, if the lamps were to fail to conduct current--perhaps because they were to become inoperative or removed--the inverter will revert to its initial mode of oscillating at its higher frequency; whereafter each 1000 milli-seconds it will for a period of 5 milli-seconds change mode to oscillate at the lower frequency.
If lamp current were to fail to flow, the magnitude of the voltage developing across the tank-capacitor will be limited by the Varistor, the (non-linear) characteristics of which are so chosen as to clamp the voltage magnitude to just the proper level to provide for proper lamp starting. Then, after the lamps have ignited, the magnitude of the voltage across the tank-capacitor will decrease to a lower level due to the loading provided by the lamps; which lower level is substantially lower than the level at which the Varistor provides for voltage clamping. Thus, after the lamps have ignited, current will cease to flow through the Varistor.
Since, in a series-excited parallel-loaded resonant high-Q L-C circuit, the power provided to the load is approximately proportional to the magnitude of the voltage developing across the load, the power provided to the Varistor when it is operative to effect voltage clamping is higher than that provided to the lamps during normal operation; and it is higher by a degree corresponding to the degree by which the lamps' starting voltage is higher than the lamps' operating voltage.
With two series-connected rapid-start lamps, the ratio between starting voltage and operating voltage is about 1.5.
Since the power provided to the lamps during normal operation is about 60 Watt, the power dissipated in the Varistor during any periods when it is constituting the load on the resonant L-C circuit will be about 90 Watt. However, even under the worst of circumstances, the Varistor can only be subject to this 90 Watt load for only about 5 milli-seconds once each 1000 milli-seconds; which means that the average dissipation of the Varistor can not exceed 0.5 Watt. Of course, these worst of circumstances would only occur if the lamp load were to be disconnected (or if it were to fail to ignite) for an extended period of time; in which case the output voltage provided from the ballast would alternate about once each second between a relatively low-magnitude minimum level and a relatively high-magnitude maximum level: the minimum level corresponding to a relatively high frequency, the maximum level corresponding to a relatively low frequency.
Additional Comments
a) The setting of adjustable resistor AR will determine the amount of power provided to the lamps during their normal operation; which implies that adjustable resistor AR may be used as a dimming means: the higher the resistance value of AR, the higher the power level provided to the lamps.
b) Transistor FET is a field effect transistor. However, a bi-polar transistor could just as well have been used.
c) It is possible by varying the amount of initial bias on the gate of transistor FET to control the effective initial impedance of this transistor, thereby effectively permitting a gradual or continuous feedback arrangement rather than the abrupt ON/OFF feedback arrangement actually described.
d) It is believed that the present invention and its several attendant advantages and features will be understood from the preceeding description. However, without departing from the spirit of the invention, changes may be made in its form and in the construction and interrelationships of its component parts, the form herein presented merely representing the presently preferred embodiment. | An inverter-type electronic fluorescent lamp ballast normally powers a fluorescent lamp by way of a series-excited parallel-loaded resonant L-C circuit. During the lamp starting phase, as well as whenever the lamp is inoperative or not connected, inverter frequency is automatically increased substantially beyond resonance, thereby preventing circuit self-destruction which would otherwise probably result whenever an inverter is used for series-exciting an unloaded resonant L-C circuit. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1 . Field of the Invention
[0004] The present invention relates to keys for security (anti-theft) fasteners such as locking wheel nuts and wheel bolts used to secure vehicular wheels.
[0005] 2. Description of the Prior Art
[0006] By way of background, locking wheel nuts and wheel bolts are commonly used to attach wheels to axle hub assemblies of automobiles and other vehicles. These security fasteners are designed with security features that are intended to thwart theft by rendering the fasteners difficult to remove with conventional tools. In particular, the fasteners do not have the usual hexagonal head pattern found on conventional nuts and bolts, and instead have smooth cylindrical side walls that cannot be gripped by standard wrenches. Fastener removal requires the use of a special security key having a key head formed with a unique key pattern that matches a corresponding lock pattern formed on the fastener end face. It is to improvements in security keys of the foregoing type and the prevention of unauthorized security fastener removal that the present invention is directed.
BRIEF SUMMARY OF THE INVENTION
[0007] The foregoing goals are achieved and an advance in the art is provided by an improved key for operating a security fastener having a lock pattern. The key features a retractable key pattern that is normally in an operational extension position in which it is enabled for substantial engagement with a security fastener having a matching lock pattern, thereby allowing operation of the matching security fastener. However, in the event that an outside tampering force in excess of a normal operational force is applied to the key pattern (such as the force that would be imparted if an attempt was made to slam the key pattern into a security fastener having a non-matching lock pattern), the key pattern will retract into a non-operational retraction position in which it is prevented from substantially engaging a security fastener having the non-matching lock pattern, thereby preventing operation of the non-matching security fastener.
[0008] In exemplary embodiments of the invention, the key includes a retraction control member that can be alternatively implemented using a biasing element, a breakable element, a crushable element or any other suitable expedient that will resist retraction of the key pattern until the tampering force is applied. The retraction control member is located to engage a key head that carries the key pattern at one end thereof. The key head is disposed in a key well that accommodates movement of the key head as the key pattern retracts. The key well is part of a key housing that includes a base end adapted for imparting torque to the key, such as by way of a handle or a gripping tool, and a fastener-receiving end that may include an open-ended shroud for guiding the key onto the end of a security fastener. A stop surface is provided on the key for contacting an area of the security fastener as the key pattern retracts to a retraction position under application of the tampering force. The stop surface prevents the security fastener's lock pattern from following the key pattern into the key well to its retraction limit.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0009] The foregoing and other features and advantages of the present invention will be apparent from the following more particular description of the preferred embodiments of the invention, as illustrated in the accompanying Drawings, in which:
[0010] FIG. 1 is an exploded perspective view of a first key exemplary construction in accordance with the invention;
[0011] FIG. 2A is a cross-sectional centerline view of the key of FIG. 1 ;
[0012] FIG. 2B is a cross-sectional centerline view of an alternative version of the key of FIG. 1 ;
[0013] FIG. 3 is a composite perspective view showing the manipulation of the key of FIG. 1 into engagement with a security fastener having a matching lock pattern;
[0014] FIG. 4A is a cross-sectional centerline view of the key of FIG. 1 with its key pattern in an operational extension position in operational engagement with a security fastener having a matching lock pattern;
[0015] FIG. 4B is a cross-sectional centerline view of the key of FIG. 1 with its key pattern in a non-operational retraction position due to a tampering force applied by a security fastener having a non-matching lock pattern;
[0016] FIG. 5 an exploded perspective view of a second exemplary key construction in accordance with the invention;
[0017] FIG. 6A is a cross-sectional centerline view of the key of FIG. 5 with its key pattern in an operational extension position;
[0018] FIG. 6B is a cross-sectional centerline view of the key of FIG. 5 with its key pattern in a non-operational retraction position;
[0019] FIG. 7 is an exploded perspective view of a third exemplary key construction in accordance with the invention;
[0020] FIG. 8A is a cross-sectional centerline view of the key of FIG. 7 with its key pattern in an operational extension position;
[0021] FIG. 8B is a cross-sectional centerline view of the key of FIG. 7 with its key pattern in a non-operational retraction position;
[0022] FIG. 9 is an exploded perspective view of a fourth exemplary key construction in accordance with the invention;
[0023] FIG. 10A is a cross-sectional centerline view of the key of FIG. 9 with its key pattern in an operational extension position;
[0024] FIG. 10B is a cross-sectional centerline view of the key of FIG. 9 with its key pattern in a non-operational retraction position;
[0025] FIG. 11 is an exploded perspective view of a fifth exemplary key construction in accordance with the invention;
[0026] FIG. 12A is a cross-sectional centerline view of view of the key of FIG. 11 with its key pattern in an operational extension position; and
[0027] FIG. 12B is a cross-sectional centerline view of the key of FIG. 11 with its key pattern in a non-operational retraction position.
DETAILED DESCRIPTION OF THE INVENTION
[0028] With reference now to the above-identified Drawings, wherein like reference numbers designate like elements in all of the several views, embodiments of the invention will now be presented by way of five exemplary key constructions representing alternative implementations of the inventive subject matter. The five exemplary constructions are respectively shown in FIGS. 1-4B , 5 - 6 B, 7 - 8 B, 9 - 10 B and 11 - 12 B. Except as otherwise indicated below when discussing alternative retraction control member constructions, it will be understood that all components used in the disclosed key constructions are fabricated from either steel, titanium, high-strength aluminum or other durable suitable materials for automotive and vehicular use.
[0000] I. FIRST EXEMPLARY KEY CONSTRUCTION
[0029] Turning now to FIG. 1 , a key 2 according to a first exemplary key construction includes a key housing 4 having a base end 6 and a fastener-receiving end 8 . By way of example only, the base end 6 can be formed as a male drive element of hexagonal shape that is either integrally formed with the main cylindrical portion of the housing 4 or attached thereto as a separate element. This configuration allows the base end 6 to receive a handle (not shown) or a tool (not shown), such as a wrench, that is capable of imparting operational torque to the housing 4 . Other suitable male (or female) configurations providing a torque transfer capability may likewise be used for the design of the base end 6 , including but not limited to external or internal shapes that are hexagonal, square, star, slotted, pinned, to name but a few. For example, in a female drive configuration, the base end 6 could be formed with a square internal opening in the housing 4 so that the key 2 can be mounted in the manner of a conventional socket to a conventional socket wrench. Note that the base end 6 could also be configured itself as a handle or a tool that is integrally formed as part of the housing 4 .
[0030] The fastener-receiving end 8 of the housing 4 can be configured as a generally tubular shroud 10 that is either integrally formed with the main cylindrical portion of the housing 4 or attached thereto as a separate element. The shroud 10 extends from a recessed ledge portion 12 of the housing 4 and can be of any suitable length consistent with its function of helping guide the key 2 onto the end of a security fastener. If desired, however, the shroud 10 could be eliminated, in which case the fastener-receiving end 8 of the housing 4 will be defined by the ledge 12 , which would no longer be recessed. The ledge 12 itself is formed as a generally annular surface that is transversely oriented relative to the housing's longitudinal axis. It terminates inwardly at the edge of a key well 14 formed in the housing's main cylindrical portion. As shown in FIG. 1 , and as described in more detail below, the key well 14 is configured to carry a biasing element in the form of a coil spring 16 and a key head 18 therein.
[0031] With additional reference now to FIG. 2A , the key well 14 is shown to include a bore 20 and a main guide way 22 . The bore 20 is adapted to carry the spring 16 and to slideably receive a stem 24 of the key head 18 . Note that the bore 20 and the stem 24 are optional insofar as the spring 16 could be located in the main guide way 22 and engage a key head configured without a stem. However, the design shown in FIG. 2A ensures proper guidance of the key head 18 by slideably supporting the stem 24 as it interacts with the spring 16 . Although the bore 20 and the stem 24 are both shown to be cylindrical in cross-sectional shape, it will be appreciated that other shapes could also be used.
[0032] One end of the bore 20 can be closed by a back wall 26 of the key well 14 in order to support the base of the spring 16 . Alternatively, in lieu of the closed back wall 26 , an annular ledge (not shown) could be formed to support the spring 16 . Thus, although the key well 14 is shown to closed-ended, it need not be so and could open to the base end of the housing 4 if desired. The other end of the bore 20 opens to the main guide way 22 . The main guide way 22 extends to a key head-receiving opening 28 where the key well 14 meets the ledge 12 . An enlarged intermediate guide flange portion 30 of the key head 18 slideably engages the sides of the key well's main guide way 22 . It will be seen that the guide flange 30 and the guide way 22 are both hexagonal in cross-sectional shape. This allows torque to be transferred from the housing 4 to the key head 18 , which can then transfer torque to a security fastener through a key pattern to be described below. It will be appreciated that many other configurations could be used to provide the required housing-key head torque transfer, including but not limited to other non-circular cross-sectional configurations, spline configurations, pin configurations, set-screw configurations, to name but a few. Indeed, any configuration that enables the key head 18 to slide within the key well 14 with little or no rotation can be used.
[0033] The end face of the key head's stem 24 contacts an end of the spring 16 that is opposite the key well's back wall 26 . The other end of the key head 18 , which faces the housing's fastener receiving end 8 , is provided with a key pattern 32 (best shown in FIG. 1 ). The key pattern 32 is shown by way of example only to be formed as a continuous raised curvilinear projection. However, it should be understood that the key pattern 32 could be implemented using any suitable male (or female) drive configuration that allows the key 2 to impart torque to a security fastener. For example, a continuous recessed curvilinear channel could be used for the key pattern 32 . Non-continuous drive patterns could also be used, including but not limited to male (or female) pin configurations, slot configurations, star configurations, hexagonal configurations, square configurations, to name but a few.
[0034] The key head 18 can be retained within the key well 14 in several ways. FIG. 2A shows one exemplary alternative in which the ledge 12 is staked around the key head-receiving opening 28 in order to trap the key head by engaging its guide flange 30 . FIG. 2B shows another construction in which the guide flange 30 is trapped by a retaining ring 34 seated in an annular groove 36 located adjacent to the key head-receiving opening 28 .
[0035] Turning now to FIGS. 3 and 4 A- 4 B, the improved security features of the key 2 will now be described. Initially, the key head 18 is in an operational extension position in which the key pattern 32 is extended toward the housing's fastener-receiving end 8 by virtue of the spring 16 . As shown in FIG. 3 , the key 2 is maneuvered into alignment with the head of a security fastener 36 and advanced onto the fastener using the shroud 10 as a guide. As shown by the double-headed arrow in FIG. 3 , slight rotation of the key 2 may be required to bring the key into proper operational alignment with the security fastener 36 . The security fastener 36 can be of any desired type, including but not limited to a vehicular lug nut or lug bolt, a vehicular spare tire winch drive, etc. The security fastener 36 could also be a non-vehicular fastener.
[0036] Among the security features of the security fastener 36 of FIGS. 3 and 4 A- 4 B is a tubular shroud 38 that freely spins relative to the remainder of the security fastener if an attempt is made to engage the shroud with a gripping tool. The security fastener 36 further includes a lock pattern 40 formed as a continuous curvilinear key receiving groove in the security fastener's generally planar end face 42 . A raised curvilinear projection could also be used if the key pattern 32 is formed as a recessed curvilinear channel. Other lock pattern configurations will be required if other key pattern configurations are used. Note that in FIGS. 3 and 4 A, the lock pattern 40 is assumed to match the key pattern 32 . FIG. 4B shows the key 2 being used with a security fastener 36 A having a non-matching lock pattern 40 A.
[0037] As shown in FIG. 4A , because the lock pattern 40 is configured to mate with the key pattern 32 , the key pattern in an operational extension position will substantially engage the lock pattern when the key 2 is advanced onto the security fastener 36 , thereby allowing the security fastener to be operated by way rotation thereof under torque applied by the key. For example, if the security fastener 36 is a vehicular lug nut or lug bolt, the key 2 can be used to turn the security fastener into and out of locking engagement in a vehicle wheel installation in which a vehicle wheel (not shown) is secured to a hub or other mounting structure (not shown).
[0038] In FIG. 4B , it is assumed that an attempt has been made to use the key 2 on a security fastener 36 A whose lock pattern 40 A is not configured to mate with the key pattern 32 . In that case, the key pattern 32 in an operational extension position will not engage the lock pattern 40 A and the non-matching security fastener 36 A cannot be operated by the key 2 . If an attempt is made to jam the key 2 onto the non-matching security fastener 36 A by applying an excessive tampering force (e.g., due to a hammer blow delivered to the base 6 of the key 2 ), the tampering force will be reacted by the immovable end face 42 A of the security fastener against the key pattern 32 . This tampering force will tend to urge the key head 18 toward the back wall 26 of the key well 14 against the biasing force of the spring 16 . This means that the key pattern 32 cannot be forced into engagement with the non-matching security fastener 36 A. Instead of being able to gain a purchase on the security fastener 36 A as a result of the tampering force, the key pattern 32 will simply retract toward the key well 14 into a non-operational retraction position. As this occurs, the spring 16 will act as a retraction control member that controls retraction of the key pattern 32 according to the amount of tampering force that is applied. Note that the spring 16 will return the key pattern 32 to an operational extension position once the tampering force is removed. Thus, the non-operational retraction position is only temporary in the first exemplary key construction represented by the key 2 .
[0039] It will be appreciated that the spring 16 should be designed so that forces associated with normal use of the key 2 to operate an authorized matching security fastener will not appreciably deflect the spring. However, the spring 16 should yield under the higher tampering force. Implementing the spring 16 as a helical coil made from steel stock of suitable gauge thickness will allow the key 2 to operate in the manner described above. It should further be understood that other spring designs may likewise be used to provide the biasing force needed for the key head retraction control function, including but not limited to Belleville spring washers as well as other biasing elements made from deformable resilient materials such as compressible rubber or the like. Resilient cushions, such as gas-filled bladders, could also be used.
[0040] As an additional security measure, a stop surface can be associated with the key housing 4 to contact an area of the non-matching security fastener 36 A as the key pattern 32 retracts. This will prevent the security fastener's non-matching lock pattern 40 A from following the key pattern 32 to its retraction limit wherein the key head 18 bottoms out in the key well 14 . The stop surface may reside at various locations on the key 2 depending on the geometry of the key and the size and shape of the non-matching security fastener 36 A. For example, as shown in FIG. 4B , a stop surface may be provided by the housing's fastener receiving end 8 if the shroud 10 is present and is of sufficient length to engage a corresponding surface of the non-matching security fastener 36 A during retraction of the key pattern 32 . In FIG. 4B , this corresponding surface is located on the front face of a tapered seat member of the non-matching security fastener 36 A. If the shroud 10 is not present, or is of reduced length, or if the security fastener 36 A has no surface to contact the shroud, the ledge 12 of the housing 4 can act as a stop surface that engages (for example) the forward end face of the non-matching security fastener's tubular shroud 38 A as the key pattern 32 retracts. In some cases, the fastener receiving end 8 and the ledge 12 of the key 2 could both act as stop surfaces in different situations depending on the type of non-matching security fastener being contacted by the key. As such, some key constructions may provide plural application-specific stop surfaces. Alternatively, it may be the case that neither the fastener receiving end 8 nor the ledge 12 engages any portion of a security fastener, in which case some other surface (such as a prong or a tang on the shroud 10 ) may be provided to perform this function.
[0000] II. SECOND EXEMPLARY KEY CONSTRUCTION
[0041] Turning now to FIGS. 5, 6A and 6 B, a key 102 according to a second exemplary key construction of the invention is similar in many respects to the key 2 of the first exemplary key construction, as indicated by the use of corresponding reference numbers incremented by a value of 100. The primary difference between the key 202 and the key 2 is that the former does not use the spring 16 as a retraction control member. Instead, the spring 16 is replaced with a breakable element 116 made from plastic (e.g., ST801 type 6/6 polyamide nylon or the like) or other readily breakable material, such as soft metal, etc. In addition, the housing 104 is modified such that the key well 114 comprises only a primary guide way 122 of hexagonal cross-sectional shape. It does not include a separate bore such as the bore 20 in the key housing 4 described above. The key head 118 is also modified insofar as it lacks a stem.
[0042] As shown in FIG. 6A , the breakable element 116 is formed with a disk-shaped base flange 116 A that rests against the back wall 126 of the key well 114 . Extending from the base flange 116 A is a central post 116 B that is sized to mate with a central longitudinal bore 118 A formed in the key head 118 . A thin, disk-shaped key pattern support flange 116 C is mounted on the post 116 B in spaced relation to the base flange 116 A. The support flange 116 C engages a base end of the key head to limit the distance that the post 116 B penetrates into the bore 118 A. The breakable element 116 thus acts as a retraction control member that maintains the key pattern 132 in an operational extension position until a tampering force is applied. More particularly, the thickness of the support flange 116 C is controlled to shear, rip, rupture or tear from the post 116 B, and/or to bend or fold, when a desired breakaway force is applied. It will be appreciated that a higher breakaway force can be obtained by increasing the thickness of the support flange 116 C, and visa versa.
[0043] In FIG. 6B , it is assumed that a tampering force has been applied to the key pattern 132 , and that the support flange 116 C has sheared at its point of connection to the post 116 B. This allows the post 116 B to advance into the bore 118 A, enabling the key head 118 to slide toward the back of the key well 114 . The key pattern 132 will thereby retract to a non-operational retraction position. Note that because the breakable element 116 is used in lieu of a biasing element, the key pattern 132 will tend to remain in a retraction position after the tampering force is removed, rendering the key 102 inoperable even for authorized use with a matching security fastener.
[0000] III. THIRD EXEMPLARY KEY CONSTRUCTION
[0044] Turning now to FIGS. 7, 8A and 8 B, a key 202 according to a third exemplary key construction of the invention is similar in many respects to the key 102 of the second exemplary key construction, as indicated by the use of corresponding reference numbers incremented by a value of 100. The primary difference between the key 202 and the key 102 is in the design of the retraction control member. In particular, a modified breakable element 216 , made from plastic (e.g., ST801 type 6/6 polyamide nylon or the like) or other readily breakable material, such as soft metal, etc., is used in lieu of the breakable element 116 described above. The housing 204 is the same design used for the housing 4 of the first exemplary key construction. The key well 214 of the housing 204 thus includes both a bore 220 and a main guide way 222 . The key head 218 is similar to the key head 18 of the first exemplary key construction, except that it includes a post 218 A extending from the stem 224 .
[0045] As shown in FIG. 8A , the breakable element 216 is formed with a main bushing 216 A that is sized to slideably engage the sides of the key well bore 220 . A thin, disk-shaped key pattern support flange 216 B is mounted on the end of the main bushing 216 A that faces the key well's main guide way 222 . The support flange 216 B engages the back of the key well's main guide way 222 . A central bore 216 C in the breakable element 216 extends through the main bushing 216 A (or at least a portion thereof). The central bore 216 C is sized to receive the key head's post 218 A. The breakable element 216 thus acts as a retraction control member that maintains the key pattern 232 in an operational extension position until a tampering force is applied. More particularly, the thickness of the support flange 216 B is controlled to shear, rip, rupture or tear from the main bushing 216 A, and/or to bend or fold, when a desired breakaway force is applied. It will be appreciated that a higher breakaway force can be obtained by increasing the thickness of the support flange 216 B, and visa versa.
[0046] In FIG. 8B , it is assumed that a tampering force has been applied to the key pattern 232 , and that the support flange 216 B has sheared at its point of connection to the main bushing 216 A. This will allow the main bushing 216 A to retreat deeper into key well's bore 220 , enabling the key head 218 to slide toward the back of the key well 214 . The key pattern 232 will thereby retract to a non-operational retraction position. Note that because the breakable element 216 is used in lieu of a biasing element, the key pattern 232 will tend to remain in a retraction position after the tampering force is removed, rendering the key 202 inoperable even for authorized use with a matching security fastener.
[0000] IV. FOURTH EXEMPLARY KEY CONSTRUCTION
[0047] Turning now to FIGS. 9, 10A and 10 B, a key 302 according to a fourth exemplary key construction of the invention is similar in many respects to the key 202 of the third exemplary key construction, as indicated by the use of corresponding reference numbers incremented by a value of 100. The primary difference between the key 302 and the key 202 is in the design of the retraction control member. In particular, a modified breakable element 316 in the form of a pin, made from plastic (e.g., ST801 type 6/6 polyamide nylon or the like) or other readily breakable material, such as soft metal, etc., is used in lieu of the breakable element 216 described above. The housing 304 is the same design used for the housing 104 of the second exemplary key construction, except that there are a pair of opposing pin-receiving holes 304 A formed in the sides of the key well 314 . The key head 318 is similar to the key head 118 of the second exemplary key construction, except that there is no longitudinal bore. Instead, a transverse bore 318 A can be provided to extend laterally through the key head's guide flange 330 .
[0048] As shown in FIG. 10A , the breakable element 316 is formed as a pin that extends through the holes 304 A in the key housing 304 and which may also extend through the key head bore 318 A, if present. Alternatively, the breakable element 316 could be located behind the key head's guide flange 330 , in which case the key head bore 318 A is not required. The breakable element 316 acts as a retraction control member that maintains the key pattern 332 in an operational extension position until a tampering force is applied. More particularly, the thickness of the breakable element 316 is controlled to shear, rip, rupture or tear, and/or to bend or fold, in two places on opposite sides of the key head 318 (i.e., at the location of the holes 304 A) when a desired breakaway force is applied. It will be appreciated that a higher breakaway force can be obtained by increasing the thickness of the breakable element 316 , and visa versa.
[0049] In FIG. 10B , it is assumed that a tampering force has been applied to the key pattern 332 , and that the breakable element 316 has sheared in the manner described above. This will allow the key head 318 to slide toward the back of the key well 314 . The key pattern 332 will thereby retract to a non-operational retraction position. Note that because the breakable element 316 is used in lieu of a biasing element, the key pattern 332 will tend to remain in a retraction position after the tampering force is removed, rendering the key 302 inoperable even for authorized use with a matching security fastener.
[0000] V. FIFTH EXEMPLARY KEY CONSTRUCTION
[0050] Turning now to FIGS. 11, 12A and 12 B, a key 402 according to a fifth exemplary key construction of the invention is similar in many respects to the key 302 of the second exemplary key construction, as indicated by the use of corresponding reference numbers incremented by a value of 100. The primary difference between the key 402 and the key 302 is in the design of the retraction control member. In particular, a crushable element 416 , made from a relatively rigid yet collapsible foam, or other readily crushable material, is used in lieu of a breakable element. The housing 404 is the same design used for the housing 4 of the first exemplary key construction. The key well 414 of the housing 404 thus includes both a bore 420 and a main guide way 422 . The key head 418 is the same design used for the key head 18 of the first exemplary key construction, and thus includes a stem 424 .
[0051] As shown in FIG. 12A , the crushable element 416 is shaped as a cylinder and resides within the key well's bore 420 . One end of the crushable element 416 is seated against the key well's back wall 426 . The other end of the crushable element 416 bears against the end face of the key head's stem 424 and supports the key head 418 against slideable movement toward the back of the key well 414 . The crushable element 416 thus acts as a retraction control member that maintains the key pattern 432 in an operational extension position until a tampering force is applied.
[0052] As shown in FIG. 12B , when a tampering force is applied to the key pattern 432 , the crushable element 416 will collapse within the bore 420 . This will allow the key head 418 to slide toward the back of the key well 414 . The key pattern 432 will thereby retract to a non-operational retraction position. Note that because the crushable element 416 is used in lieu of a biasing element, the key pattern 432 will tend to remain in a retraction position after the tampering force is removed, rendering the key 402 inoperable even for authorized use with a matching security fastener.
[0053] Accordingly, a key with a retractable key pattern has been shown and described according to several exemplary constructions. While various embodiments have been disclosed, many other variations would also be possible within the scope of the invention. For example, although various designs for implementing a retraction control function have been set forth, it should be apparent to persons skilled in the art in light of the teachings herein that there are innumerable design alternatives that could also be used. Examples include but are not limited to the use of retention elements that operate along the sides of the key well, such as ball detent mechanisms, deformable or breakable retaining rings or bushings, and flanges that are either separately attached or integrally formed on the key head or the key well, etc. Another design approach would be to establish an interference fit between the key head and the sides of the key well. Obtaining a proper interference fit with the required breakaway force could be aided by providing knurling on the key head or the key well, providing a deformable bushing between the key head and the key well, or by forming the stem of the key head as a slotted tube that is compressed by the key well side walls (or by an insert in the key well). Tapering the key well side walls or forming a chamfer therein (or providing a tapered or chamfered insert in the key well) could be used to apply a compressive force on the key head that increases as the key pattern retracts.
[0054] In view of these and many other potential alternative design possibilities, it should be understood that the invention is not to be in any way limited except in accordance with the spirit of the appended claims and their equivalents. | A key for operating a security fastener having a lock pattern includes a retractable key pattern. The key pattern has an operational extension position in which the key pattern is enabled for substantial engagement with a security fastener having a matching lock pattern, thereby allowing operation of the matching security fastener. The key pattern is also capable of retreating a non-operational retraction position in which the key pattern is not capable of substantial engagement with a security fastener having a non-matching lock pattern, thereby preventing operation of the non-matching security fastener. | 1 |
CROSS-REFERENCED TO RELATED APPLICATIONS
This application is a division of U.S. application Ser. No. 08/902,053, filed Jul. 29, 1997, now U.S. Pat. No. 5,958,970, which, in turn, is a continuation-in-part of U.S. application Ser. No. 09/813,514 filed Mar. 7, 1997, now abandoned, all aspects of which tat do not conflict with this application are incorporated herein in their entirety.
GOVERNMENT FUNDING
This application was funded, at least in part, by a grant from the United States Government, which may have certain rights therein.
BACKGROUND OF THE INVENTION
It was recently discovered that arisugacin, a natural product isolated from a culture of Penicillium, is an inhibitor of acetylcholinesterase (AChE), and on this basis arisugacin has been predicted to be effective in the treatment of Alzheimer's disease. Related compounds also showed inhibitory activity. Omura, S., et al. (1995), “Arisugacin, a Novel and Selective Inhibitor of Acetylcholinesterase from Penicillium sp. FO-4259,” J. Antibiotics 48:745-746. Arisugacin and the related compounds are tetracyclic pyrones (having four fused rings). Other tetracyclic pyrones, certain pyripyropenes, have been shown to be inhibitors of cholesterol acyltransferase (ACAT), and therefore have been predicted to be effective in the treatment of atherosclerosis and hypercholesterolemia. Omura, S., et al. (1993), “Pyripyropenes, Highly Potent Inhibitors of Acyl-CoA; Cholesterol Acyltransferase Produced by Aspergillus fumigatus,” J. Antibiotics 46:1168-1169; and “Kim, Y. K. et al. (1994), “Pyripyropenes, Novel Inhibitors of Acyl-CoA:Cholesterol Acyltransferase Produced by Aspergillus fumigatus,” J. Antibiotics 47:154-162. Pyripyropene A, one such inhibitor, is further characterized in Tomoda, H., et al. (1994), “Relative and Absolute Stereochemistry of Pyripyropene A, A Potent, Bioavailable Inhibitor of Acyl-CoA:Cholesterol Acyltransferase (ACAT),” J. Am. Chem. Soc. 116:12097-12098.
A number of multicyclic pyrones are known to the art and described in Chemical Abstracts; however, tricyclic and tetracyclic pyrones as disclosed and claimed herein, appear not to have been previously described.
There is a need for simpler inhibitors of AchE and ACAT that are useful as treatments for Alzheimer's disease, atherosclerosis and hypercholesterolemia.
SUMMARY OF THE INVENTION
The tricyclic and tetracyclic pyrones of this invention are useful as inhibitors of AChE and ACAT, and can be used in the treatment of Alzheimer's disease, atherosclerosis and Kit hypercholesterolemia. The tricyclic compounds are also potent inhibitors of cancer cell growth and macromolecule synthesis (e.g., DNA, RNA and protein synthesis) and can be used in the treatment of various forms of cancers including leukemia, ascites, and solid tumors. Further, their short-term inhibition of macromolecule synthesis is reversible following removal, but their long-term inhibition of tumor cell growth is not. Importantly, the tricyclic compounds are also powerful inhibitors of tubulin polymerization and may be useful as cell cycle-specific anticancer drugs. As hereinafter described, certain of these pyrones are useful intermediates in the synthesis of other pyrones of this invention. The tricyclic compounds are cytostatic but not overly cytotoxic.
The tricyclic pyrones of this invention include compounds selected from the group of compounds of the formula:
wherein:
T is independently CH, N, S or O;
X is independently O, NH or S;
Y is independently O, NH or S;
Z is independently CH, N, S or O;
R 1 is independently Formula I; or
R 1 and R 3 and R 4 and R 5 are, independently, H, OH, alkyl, alkenyl, alkynyl, an aromatic ring system,
wherein R and M are independently H, alkyl, alkenyl or alkynyl, an aromatic ring system, amino, amido, sulfhydryl, or sulfonyl, W is Cl, F, Br or OCI, and A is an aromatic ring system;
R 2 and R 9 are independently H or R where R is as defined above.
As used herein, the term “aromatic ring system” includes five and six-membered rings, fused rings, heterocyclic rings having oxygen, sulfur or nitrogen as a ring member, OR-substituted and R-substituted aromatic rings where R is defined as above. Preferably the substituents have one to five carbons. As used herein, the terms “alkyl,” “alkenyl,” an “alkynyl” include C1-C6 straight or branched chains. Unless otherwise specified, a general formula includes all stereoisomers.
Compounds of this invention also include compounds of the formula:
wherein:
X, Y and R 2 -R 3 are as set forth for Formula I;
R 1 is independently Formula II or as set forth for Formula I;
R 15 is independently NH 2 , OH, or OCOR′ where R′ is H, or alkyl;
R 16 is independently OH or H; and
R 15 and R 16 taken together are O;
compounds of the formula:
wherein:
X, Y, T, Z and R 2 and R 3 are as set forth in Formula I:
R 1 is independently Formula III or as set forth for Formula I; and
R 6 is H when R 7 is OH, or R 6 is OH when R 7 is H, or R 6 and R 7 taken together are ═O;
compounds of the formula:
wherein R 1 is independently Formula IV or as set forth for Formula I, and R 3 is as set forth for Formula I above; and R 2 , R 4 R 3 for Formula I above;
and compounds of the formula:
wherein R 1 is Formula V or independently is as set forth for Formula I above.
The tetracyclic pyrones of this invention include compounds selected from the group of compounds of the formula:
wherein:
R 1 and R 2 are independently as defined as R 3 as set forth for Formula I above;
R 10 and R 11 and R 13 and R 14 are independently defined as R 3 as set forth for Formula I above; and
R 12 is H, alkyl, alkenyl or alkynyl, an aromatic ring system, amino, amido, sulfhydryl, or sulfonyl.
A preferable class of compounds of this invention useful as macromolecule synthesis inhibitors in cancer cells are compounds selected from compounds of the formula:
wherein:
R 1 is independently selected from the group consisting of H, R, 3-pyridyl, R-substituted 3-pyridyl, phenyl, R-substituted, di-substituted and tri-substituted phenyl, O—R-substituted, di-substituted and tri-substituted phenyl where R is as defined above; and preferably comprises an aromatic ring;
R 2 and R 9 are independently selected from the group consisting of H and R, where R is as defined above;
R 3 , R 4 and R 5 are independently selected from the group H, R, OH, OCHO, and OR where R is as defined above; and
T and Z are independently selected from the group consisting of CH, N, S or O.
Most preferably, the compounds are selected from the group consisting of compounds of Formula 1 wherein:
R 1 is independently selected from the group consisting of alkyl, 3-pyridyl and 3,4-dimethoxyphenyl; preferably 3-pyridyl or 3,4-dimethoxyphenyl;
R 2 is independently selected from the group consisting of H and CH 3 ;
R 3 is independently selected from the group of H, OH, and OCHO;
R 4 and R 5 are independently H;
R 9 is independently selected from the group of H and isopropenyl; and
T and Z are independently CH.
Throughout the specification hereof, chemical structures are depicted and numerically labelled. The names of the numbered structures are set forth in Table 1 and indicated in boldface in the text.
TABLE 1
Names of Structures
1A
3-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]-
[i]benzopyran
1B
cis-3-5a-dimethyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
1C
trans-3-5a-dimethyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
1D
cis-3-5-a-dimethyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
1E
trans-3-5a-dimethyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
2A
3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-
b][1]benzopyran
2B
cis-3-(3-pyridyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-
1-oxopyrano[4,3-b][1]benzopyran
2C
trans-3-(3-pyridyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-
pentahydro-1-oxopyrano[4,3-b][1]benzopyran
2D
cis-3-(3-pyridyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-
pentahydro-1-oxopyrano[4,3-b][1]benzopyran
2E
trans-3-(3-pyridyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-
pentahydro-1-oxopyrano[4,3-b][1]benzopyran
3A
3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
3B
cis-3-(3,4-dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-
pentahydro-1-oxopyrano[4,3-b][1]benzopyran
3C
trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-
5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran
3D
cis-3-(3,4-Dimethoxyphenyl)-6-formyloxy-5a-methyl-1H-
5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-B][1]benzopyran
3E
trans-3-(3,4-Dimethoxyphenyl)-6-formyloxy-5a-methyl-1H-
5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran
4A
cyclohexenecarboxaldehyde
4B
3-hydroxy-2-methyl-1-cyclohexen-1-carboxaldehyde
4C
3-formyloxy-2-methyl-1-cyclohexen-1-carboxaldehyde
5A
4-hydroxy-6-methyl-2-pyrone
5B
4-hydroxy-6-(3-pyridyl)-2-pyrone
5C
4-hydroxy-6-(3,4-dimethoxyphenyl)-2-pyrone
6
3-5a-dimethyl-6-oxo-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
7
2-methylcyclohexan-1-one
8
2-methyl-2-cyclohexen-1-one
9
1,3-dithiane
10
1-[2-(1,3-dithianyl)]-2-methyl-2-cyclohexen-1-ol
11
3-[2-(1,3-dithianyl)]-2-methyl-2-cyclohexen-1-ol
12A
ethyl nicotinate
12B
ethyl 3,4-dimethoxybenzoate
13A
ethyl 5-(3-pyridyl)-3,5-dioxopentanoate
13B
methyl 5-(3,4-dimethoxyphenyl)-3,5-dioxopentanoate
14A
3-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]quinoline
14B
cis-3-5a-dimethyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b]quinoline
14C
cis-3-5a-dimethyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b]benzothiin
18
4-bromo-6-methyl-2-pyrone
19
4-azido-6-methyl-2-pyrone
20
4-amino-6-methyl-2-pyrone
21
4-mercapto-6-methyl-2-pyrone
22
tri(deacetyl)pyripyropene A
23
20(S)-camptothecin (CPT)
24
1H-6,7,8,9-tetrahydro-1-oxopyrano[4,3-b]quinoline
26
1H-3-methyl-7,8,9,10-tetrahydropyrano[4,3-c]isoquinolin-1-one
27
(S)-(-)-perillaldehyde
28
(5aS,7S)-7-Isopropenyl-3-methyl-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
29
(5aS,7S)-7-Isopropenyl-3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
30
(5aS,7S)-7-Isopropenyl-3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9-
pentahydro-1-oxopyrano[4,3-b][1]benzopyran
31
3-(Methoxycarbonylmethyl)-1H-5a,6,7,8,9-pentahydro-1-
oxopyrano[4,3-b][1]benzopyran
32
3-(Carboxymethyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-
b][1]benzopyran
33
1,8-Di-{3-[1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][I]
benzopyranyl]}-2,7-octanedione
34
(5aS,7S)-7-[2-(1-hydroxypropyl)]-3-methyl-1H-5a,6,7,8,9-
pentahydro-1-oxopyrano[4,3-b][1]benzopyran
35
(5aS,7S)-7-[1-(Formyl)ethyl]-3-methyl-1H-5a,6,7,8,9-pentahydro-
1-oxopyrano[4,3-b][1]benzopyran
36
(5aS,7S)-7-[2-(1-Hydroxypropyl)]-10-hydroxy-3-(3,4-
dimethoxyphenyl)-1H-5a,6,7,8,9,9a,10-heptahydro-1-
oxopyrano[4,3-b][1]benzopyran
37
(5aS,7S)-7-[2-(1-Pentanoyloxypropyl)]-10-hydroxy-3-(3,4-
dimethoxyphenyl)-1H-5a,6,7,8,9,9a,10-heptahydro-1-
oxopyrano[4,3-b][1]benzopyran
38A
(5aS*,9aS*,10S*)-9a,10-Epoxy-3-(3-pyridyl)-1H-5a,6,7,8,9,9a,10-
heptahydro-1-oxopyrano[4,3-b][1]benzopyran
38B
(5aS*,9aR*,10R*)-9a,10-Dihydroxy-3-(3-pyridyl)-1H-
5a,6,7,8,9,9a,10-heptahydro-1-oxopyrano[4,3-b][1]benzopyran
39
(R)-(-)-carvone
40
cis-1-iodo-3-(methanesulfonyloxy)-1-propene
41
(5R,6S)-2,6-Dimethyl-6-(cis-3-iodo-2-propenyl)-5-isopropenyl-2-
cyclohexen-1-one
42
(4aS,5R,8aS)-Methyl-(1H)-1-Oxo-4,4a,5,8,8a-pentahydro-2,5,8a-
trimethylnaphthalene-5-acetate
43
(4aS,5R,8aS)-(1H)-1-Oxo-4,4a,5,8,8a-pentahydro-2,5,8a-
trimethylnaphthalene-5-acetic acid
44
(1S,4aS,8aS)-(1H)-1-[2-(1,3-dithianyl)]-1-hydroxy-4,4a,5,8,8a-
pentahydro-2,5,8a-trimethylnaphthalene-5-acetic acid
45
(4aS,5R,8aS)-(1H)-1-carboxaldehyde-3-formyloxy-4,4a,5,8,8a-
pentahydro-2,5,8a-trimethylnaphthalene-5-acetic acid
46
(4R,4aS,6aS,12bS)-1H,11H-4,4a,5,6,6a,12b-Hexahydro-6-
formyloxy-11-oxo-9-(3-pyridyl)-4,6a,12b-trimethylnaphtho[2,1-
b]pyrano[3,4-e]pyran-4-acetic acid
47
(4aS,5S,8aS)-Methyl-(1H)-1-Oxo-4,4a,5,8,8a-pentahydro-2,5,8a-
trimethylnaphthalene-5-acetate
Preferred compounds of this invention are shown in below in Scheme 1 and include compounds selected from the group consisting of: 3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [2A]; 3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3A]; cis- and trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3D and 3E]; cis- and trans-3-(3-pyridyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [2D and 2E]; cis- and trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3B and 3C]; 3-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [1A]; cis- and trans-3-5a-dimethyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [1D and 1E]; and cis- and trans-3-(3-pyridyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [2B and 2C].
A more preferred class of compounds of this invention includes compounds selected from the group consisting of 3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [2A]; 3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3A]; cis- and trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3D and 3E]; cis- and trans-3-(3-pyridyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [2D and 2E]; cis- and trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3B and 3C]; and cis- and trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3B and 3C]; 1H-6,7,8,9-tetrahydro-1-oxopyrano[4,3-b]quinoline [24]; 1H-3-methyl-7,8,9, 10-tetrahydropyrano[4,3-c]isoquinolin-1-one [26]; (5aS*, 9aR*, 10R*)-9a, 10-Dihydroxy-3-(3-pyridyl)-1H-5a,6,7,8,9,9a, 10-heptahydro-1-oxopyrano [4,3-b][1] benzopyran [38B]; (5aS, 7S)-7-[2-(1-Pentanoyloxypropyl)]-10-hydroxy-3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9,9a, 10-heptahydro-1-oxopyrano [4,3-b][1] benzopyran [37]; (5aS, 7S)-7-Isopropenyl-3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano [4,3-b][1] benzopyran [30]; (5aS, 7S)-7-Isopropenyl-3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano [4,3-b][1] benzopyran [29]; (5aS, 7S)-7-Isopropenyl-3-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano [4,3-b][1] benzopyran [28]; and 3-(Carboxymethyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano [4,3-b][1] benzopyran [32].
A most preferred class of compounds of this invention includes compounds selected from the group consisting of 3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [2A]; 3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9-pentahydro- l -oxopyrano[4,3-b]benzopyran [3A]; cis- and trans-3 -(3,4-dimethoxyphenyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3D and 3E]; and cis- and trans-3-(3,4-dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b]benzopyran [3B and 3C]; and 1,8-Di {3-[1H-5a,6,7,8,9-pentahydro-1-oxopyrano [4,3-b] [1] benzopyranyl]}-2,7-octandione [33].
This invention also provides methods as illustrated in Schemes 1, 2, 6, 7, 8 and 9 below for making the above compounds via condensation reactions between an aldehyde of a cyclohexene having R 2 and R 3 substituents as defined above, and an ortho-oxy-substituted heterocyclic ring having as a para-substituent a reactive group capable of reacting with the β carbon of the enal function (carbon containing R 2 ) to form the tricyclic product. These anticancer drugs are easy to prepare in large quantities using few steps.
The method comprises contacting:
(a) a compound of the formula:
wherein X is as defined for Formula I;
wherein R 1 is defined as R 3 as set forth in Formula I above; and
Z is a reactive group comprising Y (as defined in Formula I above, i.e. O, S or N);
with
(b) a compound having an aldehyde substituent of the formula:
wherein:
R 2 and R 3 are as defined above for Formula I, R 6 is defined as R 3 for Formula I above, and R 4 and R 5 are as defined above for Formula I; and T and Z are independently CH, N, S or O
under reaction conditions whereby a condensation reaction takes place between said compounds of paragraphs (a) and (b) whereby reactive groups R 3 and Z react with said substituted ene aldehyde to form a compound as defined in the Formula I above.
Compounds of Formula I and Formula 1 where X≠Y may be made by means known to the art by methods analogous to those disclosed herein. Further, compounds of Formula I and Formula 1 where T≠CH, Z≠CH, R 4 ≠H, or R 5 ≠H may be made by means known to the art by methods analogous to those disclosed herein.
More preferably, the method comprises making a compound of Formula 1 comprising contacting:
wherein R 2 and R 3 are as defined for Formula 1 above, with
(b) a compound of the formula:
wherein:
R 1 is defined as R 3 as set forth for Formula 1 above.
Methods are also provided for making compounds of Formula IV above comprising reacting (a) compounds of the formula:
wherein R 1 is defined as R 3 as set forth above for Formula I;
with
(b) compounds of the formula:
wherein R 2 and R 3 are as defined above for Formula I.
Methods are provided for making compounds of Formula VI above comprising reacting (a) compounds of the formula:
wherein:
R 17 and R 18 are independently defined as R 3 as set forth for Formula I above;
R 19 is CH 2 R, wherein R is as defined as R 3 as set forth for Formula I above;
with
(b) compounds of the formula:
wherein R 1 is defined as R 3 as set forth for Formula I above.
Methods are also provided for making a compound of Formula E above comprising reacting:
wherein R 1 is defined as R 3 as set forth for Formula I above;
with
(b) a compound of the formula:
wherein X is I, Br, or Cl, and Ms is methanesulfonyl.
A method is also provided for inhibiting an enzyme selected from the group consisting of acetylcholinesterase and cholesterol acyltransferase in a patient comprising administering to the patient an effective amount of a compound of this invention. An effective amount is an amount capable of effecting measurable inhibition, preferably an amount capable of effecting inhibition equivalent or greater than that of known AChE inhibitor Tacrine or known ACAT inhibitor CP-113,818 (see Examples hereof). As is known to the art, dosage can be adjusted depending on the bioactivity of the particular compound chosen. The compound may be administered in combination with a suitable pharmaceutical carrier such as DMSO, ethyl alcohol, or other carriers known to the art.
Patients include humans, large mammals, livestock animals, pets, and laboratory animals.
A method is also provided for inhibiting macromolecule (e.g., DNA, RNA and protein) synthesis and growth of cancer cells in a patient comprising administering to the patient an effective amount of a compound of this invention. Suitable pharmaceutical carriers may be used for administration of the compound. An effective amount to inhibit macromolecule synthesis or cell growth is an amount sufficient to inhibit macromolecule production or cell growth at least as well as 20(S)-camptothecin (CPT) as measured in standard assays as described in the Examples hereof.
A method is also provided for inhibiting tubulin polymerization in a patient comprising administering to the patient an effective amount of a compound of this invention. Suitable pharmaceutical carriers may be used for administration of the compound. An effective amount is an amount capable of effecting measurable inhibition, preferably an amount capable of effecting inhibition equivalent to known tubulin polymerization inhibitor colchicine.
Methods are also provided herein for prevention of tubulin polymerization, tumor development, inhibiting the rate of tumor growth, and inducing regression of pre-existing tumors comprising administering to a patient an effective amount of a compound of this invention. An effective dosage for each purpose may be readily calculated by those of skill in the art based on effective dosages for inhibition of macromolecule synthesis, optimized and adjusted as required for individual patients.
Interestingly, Tau, which is a major component of the abnormal intracellular tangles of filaments found in the brain of Alzheimer patients, is a non-energy transducing microtubule-associated protein. If tricyclic pyrones bind to tubulin and disrupt microtubule dynamics, they should also decrease or prevent the interactions of Tau and other microtubule-associated proteins with microtubules that are involved in Alzheimer's disease.
The mechanism of action by which the compounds inhibit cancer cells is unknown; however, a possible mechanism is that the compounds bind selectively and strongly with one of the oxidative enzymes which undergoes oxidation at the C 3 -C 4 double bond to form the corresponding C 3 -C 4 epoxide and this epoxide then subsequently undergoes a ring opening reaction with a nucleophile of DNA, RNA, or enzymes in the cancer cell.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a comparison of the effects of four new tricyclic pyrone derivatives and CPT on DNA synthesis in L1210 cells in vitro. About 2.53×10 6 cells suspended in 0.5 ml of RPMI 1640 medium were incubated at 37° C. for 90 minutes in the presence or absence (control) of the indicated concentrations of drugs. The cells were then pulse-labeled for an additional 30 minutes to determine the rate of 3 H-thymidine incorporation into DNA. DNA synthesis in vehicle-treated control cells was 43,956±4,569 cpm (100±11%). The blank value (1,241±99 cpm) for cells pulse-labeled for 0 minutes with 1 μCi of 3 H-thymidine has been subtracted from the results. Bars: means±SD (n=3).
a P<0.1, significantly smaller than control; b not significantly different from control; c not different from CPT (20 μM).
FIG. 2 shows a comparison of the effects of 10 new tricyclic pyrone derivatives and CPT on DNA synthesis in L1210 cells in vitro. The protocol of the experiment was identical to that of FIG. 1, except that the cell density was 2.64×10 6 cells/0.5 ml. DNA synthesis in vehicle-treated control cells was 60,998±4,636 cpm (100±8%). The blank value (1,297±182 cpm) for cells pulse-labeled for 0 minutes with 1 μCi of 3 H-thymidine has been subtracted from the results. Bars: means±SD (n=3). a P<0.025, significantly smaller than 3B & 3C; b not significantly different from control; c not different from CPT (20 μM); d P<0.025, smaller than 2B & 2C; e not different from 1A; f P<0.025, smaller than 1D & 1E; g P<0.025, smaller than control.
FIG. 3 illustrates the concentration-dependent inhibition of DNA synthesis by the new tricyclic pyrone analog 3A () and CPT (∘) in L1210 cells in vitro. The protocol of the experiment was identical to that of FIG. 1, except that the cell density was 2.07×10 6 cells/0.5 ml. DNA synthesis in vehicle-treated control cells was 29,813±1,282 cpm (100±4%; striped area). The blank value (954±238 cpm) for cells pulse-labeled for 0 minutes with 1 μCi of 3 H-thymidine has been subtracted from the results. The concentrations of drugs are plotted on a logarithmic scale. Bars: means±SD (n=3). a P<0.005, significantly smaller than control; b not logarithmic scale. Bars: means±SD (n=3). a P<0.005, significantly smaller than control; b not significantly different from control.
FIG. 4 shows the concentration-dependent inhibition of DNA synthesis by the new tricyclic pyrone analog 2A () in L1210 cells in vitro. The protocol of the experiment was identical to that of FIG. 1, except that the cell density was 2.83×10 6 cells/0.5 ml. DNA synthesis in vehicle-treated control cells was 94,547±7,564 cpm (100±8%; striped area). The blank value (1,580±92 cpm) for cells pulse-labeled for 0 minutes with 1 μCi of 3 H-thymidine has been subtracted from the results. The concentrations of drugs are plotted on a logarithmic scale. Bars: means±SD (n=3). a P<0.025, significantly smaller than control.
FIG. 5 shows a comparison of the effects of six new tricyclic pyrone analogs and CPT on the growth of L1210 cells in vitro. Cells were plated at an initial density of 1×10 4 cells/0.5 ml/well in RPMI 1640 medium, containing 7.5% fortified bovine calf serum, and grown at 37° C. for 4 days in a humidified incubator in 5% CO 2 in air. Cells were incubated in the presence or absence ( • , control) of 50 μM 3A (▪), 2D & 2E (□),3D & 3E (▴), 2B & 2C (Δ) 2A (♦), 3B & 3C (⋄), or 10 μM CPT (∘) and their density was monitored in triplicate every 24 h using a Coulter counter. Cells numbers are plotted on a logarithmic scale.
In FIG. 6, the abilities of the drugs tested in FIG. 5 to inhibit the growth of L1210 cells in vitro are compared at days 3 (open) and 4 (striped). The results are expressed as % of the numbers of vehicle-treated control cells after 3 (396,200±38,431 cells/ml; 100±10%; open) and 4 days in culture (991,907±129,245 cells/ml; 100±13% striped). Bars: means±SD (n=3). a P<0.05, significantly smaller than control; b not significantly different from control; c not different from control or 2D & 2E.
FIG. 7 shows the concentration-dependent inhibition of the growth of L1210 cells in vitro by the new tricyclic pyrone analogs 3A and 3D & 3E. The protocol of the experiment was identical to that of FIG. 5 . Cells were incubated in the presence or absence ( • , control) of 3.12 μM 3A (▪), 3D & 3E (□) and CPT (∘), 12.5 μM 3A (▴) and 3D & 3E (Δ), or 50 μM 3A (♦) and 3D & 3E (⋄), and their density was monitored in triplicate every 24 hours. Cell numbers are plotted on a logarithmic scale.
In FIG. 8 the abilities of the concentrations of 3A tested in FIG. 7 to inhibit the growth of L1210 cells in vitro are compared at days 1 (□), 2 (▪), 3 (∘) and 4 (•). The results are expressed as % of the numbers of vehicle-treated control cells after 1 (15,387±1,723 cells/ml), 2 (54,880±6,256 cells/ml), 3 (458,280±52,244 cells/ml), and 4 (1,185,000±125,610 cells/ml) days in culture (100±11%; striped area). The concentrations of 3A are plotted on a logarithmic scale. Bars: means±SD (n=3). a Not significantly different from control; b P<0.025 and c P<0.05, significantly smaller than control.
In FIG. 9, the abilities of the concentrations of 3D & 3E tested in FIG. 7 to inhibit the growth of L1210 cells in vitro are compared at days 1 (□), 2 (▪), 3 (∘) and 4 (•). The determination of the results was identical to that of FIG. 8 . The concentrations of 3D & 3E are plotted on a logarithmic scale. Bars: means±SD (n=3). a Not significantly different from control; b P<0.05, significantly smaller than control.
FIG. 10 shows the concentration-dependent inhibition of the growth of L1210 cells in vitro by the new tricyclic pyrone analog 2A. The protocol of the experiment was identical to that of FIG. 5 . Cells were incubated in the presence or absence ( • , control) of 1.56 (▪), 3.12 (□), 6.25 (▴), 12.5 (Δ), 25 (♦) and 50 μM 2A (⋄) or 1.56 μM CPT (∘), and their density was monitored in triplicate every 24 hours. Cell numbers are plotted on a logarithmic scale.
In FIG. 11, the abilities of the concentrations of 2A tested in FIG. 10 to inhibit the growth of L1210 cells in vitro are compared at days 1 (□), 2 (▪), 3 (∘) and 4 (•). The results are expressed as % of the numbers of vehicle-treated control cells after 1 (46,480±4,462 cells/ml), 2 (135,880±13,004 cells/ml), 3 (495,440±51,823 cells/ml), and 4 (1,009,520±103,476 cells/ml) days in culture (100±10%; striped area). The concentrations of 2A are plotted on a logarithmic scale. Bars: means±SD (n=3). a Not significantly different from control; b P<0.025 and c P<0.005, significantly smaller than control.
FIG. 12 shows the concentration-dependent inhibition of the growth of L1210 cells in vitro by the new tricyclic pyrone analog 2A. The protocol of the experiment was identical to that of FIG. 5 . Cells were incubated in the presence or absence (•, control) of 0.19 (▪), 0.39 (□), 0.78 (▴), 1.56 (Δ) 3.12 (♦), 6.25 (⋄) and 12.5 μM 2A (▾) or 0.78 μM CPT (∘), and their density was monitored in triplicate every 24 hours. Cell numbers are plotted on a logarithmic scale.
In FIG. 13, the abilities of the concentrations of 2A tested in FIG. 12 to inhibit the growth of L1210 cells in vitro are compared at days 1 (□), 2 (▪), 3 (∘) and 4 (•). The results are expressed as % of the numbers of vehicle-treated control cells after 1 (50,560±2,730 cells/ml), 2 (198,987±9,452 cells/ml), 3 (862,707±39,253 cells/ml) and 4 (1,655,240±86,900 cells/ml) days in culture (100±5%; striped area). The concentrations of 2A are plotted on a logarithmic scale. Bars: means±SD (n=3). a Not significantly different from control; b< 0.05 and c P<0.005, significantly smaller than control.
FIG. 14 shows the ability of the new tricyclic pyrone analog 2A to completely inhibit polymerization of pure tubulin in a cell-free system in vitro. In a final volume of 200 μl, a solution of 2.5 mg/ml tubulin protein from bovine brain, 80 mM PIPES buffer, pH 6.8, 1 mM MgCl 2 , 1 mM EGTA, 1 mM GTP, and 10% glycerol was incubated at 35° C. for 20 minutes in the presence or absence (control) of 25 μM of compound 2A. The absorbance of the solution at OD 340 nm was measured to determine the rate of tubulin polymerization.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Tricyclic pyrones of this invention were tested for their ability to prevent L1210 leukemic cells from synthesizing macromolecules and growing in vitro. The term macromolecules, as used herein, refers to DNA, RNA and proteins. The compounds tested are listed with structures in Table 2.
TABLE 2
Compounds Tested for Antitumor Activity
TABLE 2
Compounds Tested for Antitumor Activity
Compound 23, 20(S)-camptothecin (CPT), a known anticancer drug which inhibits topisomerase I activity and exhibits a broad spectrum of antitumor activity, was also tested for purposes of comparison, as was compound 22, tri(deacetyl)pyripyropene A (Tomoda, H., et al. (1994), “Relative and Absolute Stereochemistry of Pyripyropene A, A Potent, Bioavailable Inhibitor of Acyl-CoA:Cholesterol Acyltransferase (ACAT),” J. Am. Chem. Soc. 116:12097-12098), Obata, R. et al. (1996), “Chemical modification and structure-activity relationships of pyripyropenes. 1. Modification at the four hydroxyl group,” J. Antibiotics 49:1133-1148, a tetracyclic pyrone, and compound 5B (4-hydroxy-6-(3-pyridyl)-2-pyrone), a monocyclic pyrone. The most preferred compounds of this invention were more effective than compounds 22 and 5B in inhibiting DNA synthesis and tumor cell growth, and were somewhat less effective than CPT at the concentrations tested.
This invention also provides a new chemical reaction as shown in Scheme 1 involving the condensation of pyrones with cyclohexenecarboxaldehydes to synthesize the cancer-active tricyclic pyranes of this invention. For example, equivalent molar amounts of the aldehyde and pyrone in solution, e.g., in ethyl acetate and 0.5 equivalents of L-proline, are stirred together under argon for three days, increasing the temperature from about 25° C. the first day to about 60° C. the last day, followed by dilution, washing, drying and concentrating.
More specifically, a simple synthesis of tricyclic pyrones with the general structure as depicted in Formula 1 (Scheme 1) is provided using a coupling reaction of 1-cyclohexenecarboxaldehydes (4) and 6-substituted 4-hydroxy-2-pyrones (5). For example, treatment of 1-cyclohexenecarboxaldehyde (4A) with one equivalent of 4-hydroxy-6-methyl-2-pyrone (5A) and 0.5 equivalent of L-proline in ethyl acetate at 70° C. under argon for 12 hours provided an 80% yield (based on reacted pyrone 5A) of 1A (Scheme 2). The structure of 1A was determined by 1 H and 13 C NMR, mass spectrometry, IR, elemental analysis, and single-crystal X-ray analysis.
Similarly, Pyrone 5A also condensed with carboxaldehydes 4B and 4C separately in the presence of 0.5 equivalent of L-proline or catalytic amount of piperidine and acetic acid in ethyl acetate at 60-80° C. to give a 72% yield of a mixture of 1B and 1C (in a ratio of 1.6:1; determined by 1 H NMR spectrum) and a 62% yield of a mixture of 1D and 1E (in a ratio of 3:1), respectively (Scheme 2). Compounds 1B and 1C were not separated; however, oxidation of this mixture with 1,1,1-triacetoxy-1,1-dihydro-1,2-benziodoxol-3(1H)-one 1 in CH 2 Cl 2 at room temperature gave the corresponding C-6 ketone 6. Reduction of ketone 6 with diisobutylaluminum hydride in THF provided pure cis-alcohol 1B. Pyranobenzopyrans 1D and 1E were separated by column chromatography and the structure of the cis-isomer, 1D, was unequivocally determined by a single-crystal X-ray analysis. Basic hydrolysis of pure 1D with K 2 CO 3 in MeOH at room temperature gave pure alcohol 1B (Scheme 3).
Aldehydes 4B and 4C were synthesized by a modification of the procedure reported by Corey and Erickson (Corey, E. J. and Erickson, B. W. (1971) “Oxidative hydrolysis of 1,3-dithiane derivatives to carbonyl compounds using N-halosuccimide reagent,” J. Org. Chem. 36(3):553-560) which is depicted in Scheme 4. Bromination of 2-methylcyclohexanone (7) with 1 equivalent of N-bromosuccinimide (Rinne, W. W. et al., “New methods of preparation of 2-methylcyclohexen-1-one,” J. Am. Chem. Soc. (1950) 72:5759-5760) in refluxing CCl 4 for 12 hours gave quantitative yield of 2-bromo-2-methylcyclohexanone. Dehydrobromination of this bromide with three equivalents of Li 2 CO 3 and three equivalents of LiBr in N,N-dimethylformamide (DMF) (Stotter, P. L. and Hill, K. A., “α Halocarbonyl Compounds. II. A Position-Specific Preparation of α-Bromo Ketones by Bromination of Lithium Enolates. A Position-Specific Introduction of α, β-Unsaturation into Unsymmetrical Ketones,” J. Org. Chem. (1973) 38:2576-2578) at 130° C. for 3 h provided a 72% yield of 2-methyl-2-cyclohexen-1-one (8). A 1,2-addition reaction of 8 with 1.5 equivalents of lithiated 1,3-dithiane [generated from 1,3-dithiane (9) with n-BuLi in THF] in THF at −10° C. to give a 96% yield of the 1,2-adduct 10. Rearrangement of 10 with 1% sulfuric acid in p-dioxane (52% yield) followed by removal of the dithiane protecting group of the resulting alcohol, 11, with N-chlorosuccinimide (NCS) and silver nitrate in acetonitrile-water gave aldehyde 4B (50% yield). Alcohol 4B is not a stable compound and decomposes upon standing at room temperature in a few days. A more stable material, 4C, was synthesized in a better yield from the rearrangement reaction of 10 in formic acid-THF in the presence of catalytic amount of p-toluenesulfonic acid (70% yield) followed by removal of the dithiane moiety with NCS-AgNO 3 (59% yield) (Scheme 4). In the formic acid rearrangement reaction, besides the desired product, 1-[2-(1,3-dithianyl)]-3-formyloxy-2-methyl-1-cyclohexene, 9% yield of 3-[2-(1,3-dithianyl)]-2-methyl-2-cyclohexen-1-ol (11) was isolated.
To demonstrate the generality of the newly-developed condensation reaction (i.e., Scheme 2), other pyrones such as 5B and 5C were also prepared and used in the condensation reaction. Scheme 5 outlines the preparation of 5B and 5C by following a small modification of the reported procedure (only 5B was reported)(Narasimhan, N. S. and Ammanamanchi, R., “Mechanism of acylation of dilithium salts of β-ketoesters: an efficient synthesis of anibine,” J. Org. Chem (1983) 48:3945-3947). Treatment of ethyl acetoacetate in diethyl ether with 2.5 equivalents of lithium diisopropylamide (LDA) at 0° C. for 1 h followed by 1 equivalent of ethyl nicotinate (12A) gave an 87% yield of triketone 13A (Scheme 5). Cyclization of 13A at 150° C. under 3 mm Hg reduced pressure for 0.5 h gave an 89% yield (based on 10.9% of recovered starting triketone) of pyrone 5B. Similarly, pyrone 5C was synthesized from ethyl 3,4-dimethoxybenzoate (12B). However, during the work-up procedure of coupling reaction of ethyl acetoacetate and 12B, the corresponding carboxylic acid of 13B was isolated, which upon methylation with diazomethane in methylene chloride and diethyl ether afforded a 56% yield of methyl ester 13B. Intramolecular cyclization of 13B gave a 70.5% yield (based on 60% recovery of starting triketone 13B) of 5C.
Condensation of aldehyde 4A with pyrones 5B and 5C separately in the presence of 0.5 equivalent of L-proline in ethyl acetate at 70° C. generated pyranobenzopyrans 2A and 3A in 73% and 62% yield, respectively (Scheme 6). In the condensation of formyloxy aldehyde 4C, some of the formyloxy group was hydrolyzed to produce the corresponding alcohol. Hence, treatment of aldehyde 4C with pyrone 5B and 0.5 equivalent of L-proline in ethyl acetate at 70° C. afforded 39% yield of formates 2D and 2E (in a ratio of 2:1) and 11% yield of alcohols 2B and 2C (ratio of 2:1).
Similarly condensation of 4C and 5C gave a 48% yield of 3D and 3E (2:1) and a 24% yield of 3B and 3C (2:1). In general, these cis and trans isomers (such as 3D and 3E, etc.) are separable by silica gel column chromatography (see Experimental Section). Condensation of alcohol 4B with pyrone 5C also provides a mixture of 2:1 ratio of the cis and trans adducts 3B and 3C.
This condensation reaction apparently is a general reaction and therefore can be applied to nitrogen and sulfur analogs. Hence, general structures, 14 (Scheme 7), can be synthesized from this reaction and subsequent chemical conversion of compounds 1-3 and 14 will provide a large number of derivatives, some of which are outlined in Scheme 7, such as 15 and 16. In Scheme 7, the synthesis of nitrogen analogs, 14A and 14B, and a sulfur analog, 14C, are demonstrated. The precursor pyrone 20 is a known compound (Cervera, M. et al., “R-4-Amino-6-methyl-2H-pyran-2-one, Preparation and Reactions with Aromatic Aldehydes,” Tetrahedron (1990) 46:7885-7892). We have already prepared this compound and the reactions are depicted in Scheme 7.
Additionally, a simple synthesis of nitrogen-containing tricyclic pyrones with general structure as depicted in Formulas IV and V is provided using a coupling reaction of 4-amino-pyrones and 1-cyclohexenecarboxaldehydes. Syntheses for the 5-nitrogen analogs 24 and 26 are shown in Scheme 8. It should be noted that nitrogen analog 14A was expected to be found from the reaction of 20 and 4A. However, 14A undergoes dehydrogenation under the reaction conditions to give compound 24. The synthesis of the 5-nitrogen analogs 24 and 26 were accomplished by heating 4-aminopyrone 20 with aldehyde 4A in the presence of a catalytic amount of(S)-(+)-10-camphorsulfonic acid in toluene at 85° C. to give 19% yield (based on unrecovered starting material) and 48% yield of the isomer 26 (Scheme 8b). The NMR spectra alone cannot determine the structures of 24 and 26. Single crystals of 24 and 26 were obtained (separately) and their structures were firmly established by single-crystal X-ray analyses.
A remarkable asymmetric induction was also observed for the newly-developed condensation reaction from a C-4 stereogenic center in the carboxaldehyde, such as (S)-(−)-perillaldehyde (27). Treatment of (S)-27 with pyrone 5A, 5B, and 5C separately gave single diastereomers 28 (78% yield), 29 (65% yield), and 30 (63% yield), respectively (Scheme 9). The structure of 28 was firmly established by single-crystal X-ray analysis and the data from 1 H NMR spectra also agrees with the same stereochemical assignment: 5aS and 7S: the C-5a proton (for example, in 28) resonates at δ5.15 ppm as a doublet of a doublet with J=11.2 Hz and 5.2 Hz (axial-axial and axial-equatorial couplings), indicative of an axial hydrogen (at C-5a).
To demonstrate the possibility of preparing various substituted derivatives, several chemical manipulations were also performed on the newly-developed tricyclic pyrones. Scheme 10 summarizes these manipulations. Deprotonation of 1A with lithium diisopropylamide (LDA) in THF at −78° C. followed by methyl chloroformate gave a 72% yield of methyl ester 31. Basic hydrolysis of 31 with KOH in THF and H 2 O provided a good yield of the acid 32. The lithiated anion derived from 1A and LDA also reacted with 0.5 equivalent of dielectrophile, adipoyl chloride, to produce diketone 33 (which exists as the enol form). The isopropenyl group of C-7 substituted tricyclic pyrones such as 28 can be hydroxylated with 1 equivalent of borane-THF followed by NaOH-30% H 2 O 2 to give primary alcohols 34 (69% yield; two inseparable diastereomers at C-12). Oxidation of alcohols 34 with 1,1,1-triacetoxy-1,1-dihydro-1,2-benziodoxol-3(1H)-one in methylene chloride gave an 87% yield of aldehydes 35.
When a greater than 1 equivalent of borane was used, both C-11 and C-9a double bonds can be oxidized to afford a mixture of diols such as 36 (2 diastereomers at C-11). Hence, hydroboration of pyrone 30 with excess of borane in THF followed by NaOH-30% H 2 O 2 gave diol 36 as a 1:1 mixture of two diastereomers at C-11. Acylation of 36 with pyridine and valeryl chloride in methylene chloride gave good yield of ester 37. C-9a double bond of 2A was epoxidized with 1 equiv of HCl (to protonate the pyridine nitrogen) followed by 1 equiv of m-chloroperbenzoic acid (MCPBA) to give a 1:4.1 ratio of 38A and 38B.
In addition to tricyclic pyrones, this invention provides a facile synthesis of tetracyclic pyrones (such as 46, Scheme 11). Treatment of(R)-carvone (39) with lithium diisopropylamide (LDA) in THF at −40° C. and MeI (−30° C.) gave an excellent yield of the corresponding C-6-monomethylated product. The regiospecific alkylation of carvone at C-6 is a known reaction (Gesson, J-P et al., “A New Annulation of Carvone to Chiral Trans and Cis Fused Bicyclic Ketones,” Tetrahedron (1986) 27:4461-4464). Subsequently, alkylation of this methylated product with LDA in THF at 0° C., followed by 1 equivalent of hexamethyl-phosphoramide (HMPA), and cis-1-iodo-3-(methanesulfonyloxy)-1-propene (40) at 0° C. then room temperature gave a 73% yield of iodide 41 as a single diastereomer and 14% recovery of 6-monomethylated carvone (Scheme 11). No other stereoisomer was detected. Cyclization of iodide 41 with palladium acetate, triphenylphosphine, silver carbonate, CO, and MeOH in DMF at 32° C. gave a 50% yield (isolated) of ester 42. Ester 42 was converted into its carboxylic acid 43 in 96% yield by the treatment with KOH in MeOH and water at 25° C. As far as we know, this is the shortest route for the synthesis of optically pure trans-decalinone derivatives, such as 42; in this synthesis, no protecting group is needed.
Addition reaction of acid 43 with the lithiated anion of 9 in THF gave adduct 44 which can be converted into aldehyde 45. Condensation of 45 with pyrone 5B will give tetracyclic pyrone 46 (a new compound).
A 23% yield of the corresponding β-isomer, compound 47, was also isolated from the above palladium-cyclization reaction. The stereochemistry of these compounds, 42 and 47, were firmly established by 2D NOESY spectroscopy and the results are depicted in structure 47 (Scheme 12). For example, in the 2D NOESY spectrum of the minor product, 47, NOE appears between C4a-H and C-10-methyl; and C-11-CH 2 and C-13-CH 2 . The NMR signals of C-13 and C-10 methyls of 42 are close to each other, hence it is difficult to determine their NOE.
Clearly, as will be appreciated by one skilled in the art, many other chemical manipulations can be carried out on the tricyclic and tetracyclic pyrones to produce various useful biologically active drugs. Additionally, the reactions illustrated in Schemes 1-11 can be modified to produce similar compounds, as will be appreciated by those skilled in the art.
The following examples illustrate the invention:
EXAMPLES
Compound Synthese
General Methods. Nuclear magnetic resonance spectra were obtained at 400 MHz for 1 H and 100 MHz for 13 C in deuteriochloro-form, unless otherwise indicated. Infrared spectra are reported in wavenumbers (cm −1 ). Mass spectra were taken from a Hewlett Packard 5890 Series II, GC-HPLC-MS. FAB spectra were taken by using Xe beam (8 KV) and m-nitrobenzyl alcohol as matrix. Davisil silica gel, grade 643 (200-425 mesh), was used for the flash column chromatographic separation. THF and diethyl ether were distilled over sodium and benzophenone before use. Methylene chloride was distilled over CaH 2 and toluene and benzene were distilled over LiAlH 4 . Ethyl acetate was dried over CaCl 2 and filtered and distilled under argon atmosphere.
General Procedure for the Condensation of Pyrone and Enal
The following reaction procedures are representative of the condensation reactions of this invention.
cis- and trans-3,5a-Dimethyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyranol[4,3-b][1]-benzopyran (1D and 1E)
A solution of 0.147 g (0.88 mmol) of aldehyde 4C, 0.11 g (0.88 mmol) of pyrone 5A, and 0.05 g (0.4 mmol) of L-proline in 10 mL of ethyl acetate was stirred under argon at 25° C. for 1 day, 40° C. (bath temperature) for 3 days, and 60° C. for 1 day. The mixture was diluted with 120 mL of methylene chloride, washed with 50 mL of saturated aqueous NaHCO 3 , and then with 50 mL of brine, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using a gradient mixture of hexane and diethyl ether as eluant to give 0.1133 g (46.5% yield) of 1D and 0.0378 g (15.5% yield) of 1E. Compound 1D: mp 138-140° C. IR (Nujol) ν 2980, 1720, 1690, 1630, 1550, 1110; 1 H NMR δ8.14 (d, J=1 Hz, 1 H, CHO), 6.18 (d, J=2.2 Hz, 1 H, C10 H), 5.73 (s, 1 H, C4 H), 5.31 (dd, J=11.6 Hz, 4.4 Hz, 1 H, C6 H, axial H), 2.39-2.33 (m, 1 H), 2.29-2.23 (m, 1 H), 2.19 (d, J=0.44 Hz, 3 H, Me), 2.12-2.05 (m, 1H), 1.88-1.8 (m, 1 H), 1.7-1.5 (m, 2 H), 1.54 (s, 3 H, Me); 13 C NMR δ162.4 (s, C═O), 162.32 (s), 160.36 (s, 2C), 132.74 (s, C10a), 112.51 (d, C10), 100.08 (d, C4), 97.7 (s, C9a), 84.4 (s, C5a), 76.46 (d, C6), 31.3 (t), 29.26 (t), 23.12 (t), 20.31 (q, Me), 18.88 (q, Me); MS.FAB, m/z 277 (M+1, 100%), 230, 139, 91. Analysis calc for C 15 ,H 16 O 5 : C, 65.21; H, 5.84. Found: C, 65.47; H, 5.61. Single crystals were obtained from the recrystallization in ether and the structure was unequivocally determined by an X-ray analysis.
Compound 1E: 1H NMR δ8.11 (d, J=0.92 Hz, 1 H, CHO), 6.23 (d, J=1.6 Hz, 1 H, C10 H), 5.72 (s, 1H, C4 H), 2.44-2.28 (m, 2 H), 2.19 (d, J=0.6 Hz, 3 H, Me), 2.1-2.0 (m, 1 H), 1.9-1.64 (a series of m, 3 H), 1.57 (s, 3 H, Me); MS.FAB, m/z 277 (M+1, 100%). Basic hydrolysis of 1E with K 2 CO 3 in MeOH gave the corresponding C6 alcohol having exact same NMR as the trans-alcohol obtained from the condensation of pyrone 5A and alcohol 4B.
3-Methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (1A)
A solution of 0.1 g (0.91 mmol) of cyclohexenecarboxaldehyde (4A), 0.115 g (0.91 mmol) of 4-hydroxy-6-methyl-2-pyrone (5A), and 0.052 g (0.455 mmol) of L-proline in 5 mL of ethyl acetate was heated at 70° C. under argon atmosphere for 24 h. The mixture was cooled to room temperature, diluted with 100 mL of methylene chloride, washed with saturated aqueous NaHCO 3 solution twice (30 mL each), with water (60 mL), and then with brine (60 mL), dried (MgSO 4 ), filtered, and concentrated to give 0.20 g of crude product. Column chromatography on silica gel of the crude product using a gradient mixture of hexane:ether as eluant gave 0.15 g (80% yield based on recovered starting pyrone) of 1A and 0.006 g (5% recovery) of 5A. Compound 1A: mp 110-112° C.; X-ray analysis was carried out on a single crystal obtained from the recrystallization from ether-hexane and the structure was solved. IR (Nujol) ν 1710 (s, C═O), 1630 (C═C), 1560. 1 H NMR δ6.07(s, 1 H C10H), 5.7 (s, 1H, C4H), 5.02 (dd, J=11.5 Hz, 1H, C5aH), 2.41 (m, 1H, C9H), 2.18 (s, 3H, Me), 2.13 (m, 1H, C5aH), 2.02-1.88 (m, 2H), 1.8-1.7 (m, 2H), 1.5-1.4 (m, 2H); 13 C NMR δ174 (s, C═O), 163.24 (s, C3), 161.38 (s, C4a), 133.06 (s, C10a), 109.17 (d, C10), 99.76 (d, C4), 97.33 (s, C9a), 79.69 (s, C5a), 35.15 (t, C9), 33.14 (t, C6), 26.89 (t, C7), 24.52 (t, C8), 20.06 (q, Me); MS (CI) m/z 219 (M+1). Analysis Calculated for C 13 H 14 O 3 : C 71.54; H 6.47. Found: C, 71.39; H, 6.53.
Preparation of 2-methyl-2-cyclohexen-1-one (8)
A solution of 15 g (0.134 mol) of 2-methyl-1-cyclohexanone (7) and 23.84 g (0.134 mol) of N-bromosuccinimide in 150 mL of carbon tetrachloride was stirred and heated to reflux for 12 h under argon. The mixture was cooled to room temperature, filtered through Celite to remove succinimide and the filter cake was washed with 150 mL of ether. The filtrate was concentrated to give 25.6 g (100% yield) of 2-bromo-2-methyl-1-cyclohexanone. 1 H NMR δ3.21 (td, J=16 Hz, 8 Hz, 1H, CH—CO), 2.36 (m, 2H), 2.06 (m, 2H), 1.82 (s, 3H, Me), 1.77 (m, 2H), 1.62 (m, 1H).
A mixture of 25.6 g (0.134 mol) of the above 2-bromo-2-methylcyclohexanone, 29.7 (0.4 mol) of Li 2 CO 3 and 34.9 g (0.4 mol) of LiBr in 300 mL of DMF was heated at 130° C. under argon for 3 h. The reaction mixture was cooled to room temperature, diluted with 400 mL of water, and extracted three times with ether (300 mL×2 and 200 mL). The combined extract was dried (MgSO 4 ), concentrated on a rotary evaporator to give 12.96 g of crude product which was subjected to vacuum distillation to give 10.6 g (72% yield) of 8, bp. 90-95° C./45 mm Hg; Lit. (Rinne, W. W. et al., “New Methods of Preparation of 2-methylcyclohexen-1-one,” J. Am. Chem. Soc (1950) 72:5759-5760) 93-97° C./25 mm Hg; 1 H NMR δ6.75 (broad s, 1H, ═CH), 2.42 (dd, J=5.6 Hz, 5 Hz, 2 H), 2.33 (m, 2H), 1.95 (pent, J=8 Hz, 2 H), 1.78 (q, J=2 Hz, 3 H, Me); 13 C NMR δ199.88 (s, C═O), 145.61 (d, ═CH), 135.65 (s, ═C), 38.33 (t), 26.04 (t), 23.32 (t), 15.97 (t).
1-[2-(1,3-Dithianyl)]-2-methyl-2-cyclohexen-1-ol (10)
To a cold (−10° C.) solution of 6.71 g (55.9 mmol) of 1,3-dithiane (9; commercially available) in 50 mL of THF under argon was added 24.6 mL (55.9 mmol; from a 2.27 M solution in hexane) of n-BuLi dropwise via syringe over 35 minutes and the resulting solution was stirred for 2 hours. In a separate flask, a solution of 4.10 g (37.7 mmol) of 8 in 25 mL of THF was prepared and this solution was added via cannula into the above dithiane anion solution. The solution was stirred at −10° C. for 1 h and kept in the refrigerator for 18 h, diluted with 100 mL of water, stirred for 10 minutes, and extracted three times with diethyl ether (100, 75, and 50 mL). The combined extract was washed twice with brine (2×100 mL), dried (MgSO 4 ), filtered, concentrated to give 13.147 g of crude product. Column chromatographic separation on silica gel using a gradient mixture of hexane:ether as eluant gave 8.208 g (96% yield) of 10 as an oil. 1 H NMR δ5.74 (t, J=4 Hz, 1H, ═CH), 4.42 (s, 1H, CH—S), 3.0-2.8 (m, 4H CH 2 —S), 2.28 (s, 1 H, OH), 2.16-1.6 (series of m, 8 H), 1.82 (broad s, 3 H, Me); 13 C NMR δ133.81 (s, ═C), 130.25 (d, ═CH), 74.04 (s, CO), 59.13 (d, CH—S), 33.88 (t, CH 2 S), 31.78 (t, CH 2 S), 31.33 (t, CH 2 ), 26.37 (t, CH 2 ), 25.61 (t, CH 2 ), 18.73 (t, CH 2 ), 17.75 (q, Me); MS (EI) m/z 230 (M + ).
3-[2-(1,3-Dithianyl)]-2-methyl-2-cyclohexen-1-ol (11)
A solution of 1.031 g (4.48 mmol) of alcohol 10 in 50 mL of p-dioxane and 75 mL of 1% aqueous solution of H 2 SO 4 was stirred at 25° C. for 5.5 h, and then extracted three times with diethyl ether (100 mL each). The combined extract was washed with 80 mL of saturated aqueous NaHCO 3 , twice with water (80 mL each) and 80 mL of brine, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using a gradient mixture of hexane and diethyl ether as solvent to give 0.533 g (58% yield based on recovered starting material 10) of 11 as an oil and 0.11 g (11% recovery) of 10. Compound 11: 1 H NMR δ5.09 (s, 1 H, CHS), 3.97 (broad s, 1 H, CHO), 3.04-2.95 (m, 2 H, CH 2 S), 2.87-2.81 (m, 2 H, CH 2 S), 2.32-2.24 (m, 1 H), 2.16-2.07 (m, 2 H), 1.91 (t, J=4 Hz, 3 H, Me), 1.89-1.58 (a series of m, 5 H); 13 C NMR δ132.89 (s, C═), 131.85 (s, ═C), 69.6 (d, CO), 51.11 (d, CHS), 31.81 (t), 31.36 (2 C, t, CH 2 S), 26.6 (t), 25.45 (t), 18.48 (t), 16.41 (q, Me); MS (EI) m/z 230 (M+). Analysis Calc. for C 11 H 18 OS 2 : C, 57.35; H, 7.87. Found: C, 57.56; H, 8.10.
3-Hydroxy-2-methyl-1-cyclohexen-1-carboxaldehyde (4B)
To a flask containing a stirring bar, 0.197 g of AgNO 3 (1.16 mmol) and 0.139 g (1.04 mmol) were added and the content was dried under vacuum, maintained under argon atmosphere, and 6 mL of CH 3 CN and 2.5 mL of H 2 O were added. The flask was stirred and cooled over ice-water bath, and a solution of 0.059 g (0.26 mmol) of 11 in 5 mL of acetonitrile was added drop wise via cannula. The solution was stirred at 0° C. for 45 min, and 1 mL each of saturated aqueous Na 2 SO 3 and Na 2 CO 3 were added at 1 min interval, and then 20 mL of a 1:1 mixture of CH 2 Cl 2 and petroleum ether was also added. The resulting mixture was filtered through Celite and the solid carefully washed with 120 mL of 1:1 mixture of CH 2 Cl 2 and petroleum ether. The filtrate was transferred into a separatory funnel and the water layer was removed. The organic layer was washed with 10 mL of saturated aqueous NaHCO 3 , dried (MgSO 4 ), concentrated to give 31.5 mg of the crude aldehyde 4B. The 1 H NMR spectrum of the crude product indicated 18 mg (50% yield) of the desired aldehyde and 13 mg of succinimide. This material can be used directly in the next reaction without further purification. In a separated reaction, the mixture was separated on silica gel flash column chromatography and provided 18 mg (50% yield) of pure 4B. Aldehyde 4B is not a stable compound and elemental analysis was not performed. 1 H NMR δ10.18 (s, 1 H, CHO), 4.16 (broad s, 1 H, CH—O), 2.27 (s, 3 H, Me), 2.31-1.6 (a series of m, 6 H); 13 C NMR δ192.37 (s, C═O), 154.24 (s, C═), 134.96 (s, C═), 70.32 (d, C—O), 31.79 (t), 22.7 (t), 17.91 (t), 14.85 (q, Me); MS, FAB m/z 141 (M+1, 100%), 140 (M+).
3-Formyloxy-2-methyl-1-cyclohexen-1-carboxaldehyde (4C)
A solution of 0.494 g (2.15 mmol) of alcohol 10 and three crystals of p-toluenesulfonic acid (anhydrous) in 2.43 mL of formic acid and 15 mL of THF was stirred under argon at 25° C. for 16 h. The solution was diluted with 100 mL of diethyl ether, washed with 40 mL of saturated aqueous NaHCO 3 , and 50 mL of brine, dried (MgSO 4 ), concentrated, and column chromatogtaphed on silica gel using a gradient mixture of hexane and diethyl ether as eluant to give 0.388 g (70% yield) of 1-[2-(1,3-dithianyl)]-3-formyloxy-2-methyl-1-cyclohexene and 0.048 g (9% yield) of alcohol 11. 1-[2-(1,3-dithianyl)]-3-formyloxy-2-methyl-1-cyclohexene: 1 H NMR δ8.12 (s, 1 H, CHO), 5.36 (broad s, 1 CH—O), 5.1 (s, 1 H, CHS), 3.05-2.95 (m, 2 H, CH 2 S), 2.9-2.8 (m, 2 H, CH 2 S), 2.4-2.3 (m, 1 H), 2.2-2.05 (m, 2 H), 1.94-1.6 (m, 5 H), 1.78 (s, 3 H, Me); 13 C NMR δ160.97 (s, C═O), 135.18 (s, C═), 128.43 (s, C═), 71.68 (d, C—)), 50.95 (d, CS), 31.34 (t, 2 C, CS), 28.7 (t), 26.43 (t), 25.42 (t), 18.55 (t), 16.31 (q, Me); MS, FAB m/z 259 (M+1), 258 (M+).
To a dried 100 mL-round-bottomed flask 1.19 g (7 mmol) of AgNO 3 , 0.828 g (6.2 mmol) of N-chlorosuccinimide, 40 mL of CH 3 CN and 16 mL of H 2 O were added under argon, and the solution was stirred and cooled over ice-water bath. To it, a solution of 0.4 g (1.55 mmol) of 1-[2-(1,3-dithanyl)]-3-formyloxy-2-methyl-1-cyclohexene in 10 mL of CH 3 CN was added drop-wise over 30 min. To the reaction solution, 2 mL saturated aqueous solution of NaSO 3 , 2 mL of saturated aqueous NaCl solution, and 20 mL of a 1:1 mixture of CH 2 Cl 2 :petroleum ether were added sequentially at 1 minute intervals. The whole mixture was then filtered through Celite, washed with 100 mL of CH 2 Cl 2 and petroleum ether. The filtrate was transferred into a separatory funnel, the water layer was separated and extracted with 40 mL of CH 2 Cl 2 . The combined organic layers were dried (MgSO 4 ), filtered, concentrated, and column chromatographed on silica gel using a gradient mixture of hexane and diethyl ether as eluant to give 0.154 g (59% yield) of pure 4C; IR (neat) ν 2750, 1720, 1680 (C=O); 1 H NMR δ10.2 (s, 1 H, CHO), 8.18 (d, J=0.8 Hz, 1 H, formyloxy CH), 5.53 (t, J=4.8 Hz, 1 H, CH—O), 2.39-2.3 (m, 1 H), 2.14 (s, 3 H, Me), 2.17-2.08 (m, 1 H), 1.94-1.6 (a series of m, 4 H); 13 C NMR δ191.59 (s, C═O aldehyde), 160.66 (s, C═O of formyloxy), 148.69 (s, C═), 137.36 (s, C═), 71.72 (d, CH—O), 28.57 (t), 22.48 (t), 17.89 (t), 14.76 (q, Me); MS, FAB m/z 169 (M+1), 168 (M+).
Ethyl 5-(3-pyridyl)-3,5-dioxopentanoate (13A)
To a cold (−10° C.) solution of 13.45 mL (96.2 mmol) of diisopropylamine in 150 mL of diethyl ether under argon was added 42.36 mL (96.2 mmol; 2.27 M solution in hexanes) of n-BuLi via syringe and the solution was stirred for 1 h. In a separated flask, 5 g (38.5 mmol) of freshly distilled ethyl acetoacetate and 60 mL of diethyl ether were added and the solution was cooled to −78° C. To it, the above LDA solution was added via cannula, then 5.8 mL (38.5 mmol) of N,N,N′,N′-tetramethylethylenediamine (TMEDA) (distilled from LiAlH 4 ) was added via syringe, and the solution was stirred at 0° C. for 3 h. To this dianion solution, a solution of 5.81 g (38.5 mmol) of ethyl nicotinate (freshly distilled) in 60 mL of diethyl ether was added via cannula and the reaction solution was warmed to room temperature and stirred for 30 h. To the solution, 5.5 mL of acetic acid was added and stirred for 10 min, filtered through fritted funnel, and the solid (desired product; exists as a protonated salt) was washed with 200 mL of diethyl ether. The filtrate was concentrated to give 1.691 g of material and the NMR spectrum indicated that it is a mixture of starting material and some unidentified components. The solid was transferred into a beaker and dissolved in 160 mL of distilled water and 60 mL of 1 N HCl, and extracted three times with methylene chloride (120 mL each). The combined extract was washed with 100 mL of brine, dried (MgSO 4 ), concentrated to give 7.921 g (87.5% yield) of the desired product 13A. 1 H NMR spectrum of this material indicated it is sufficiently pure and can be used in the next reaction without purification. Mp 38.5-39° C.; 1 H NMR δ9.07 (s, 1 H, C-2′ H, pyr.), 8.74 (d, J=4.6 Hz, 1H, C6′H, pyr.), 8.16 (d, J=8 Hz, C4′H), 7.41 (dd, J=8 Hz, 4.6 Hz, C5′H), 6.32 (s, 1 H, ═CH of enol; the compound completely exists as enol form at C4), 4.22 (q, J=7.2 Hz, 2 H, OCH 2 ), 3.5 (s, 2 H, CH 2 —C═O), 1.3 (t, J=7.2 Hz, 3 H, Me); 13 C NMR δ189.93 (s, C═O, C3), 179.97 (s, O—C═, C5), 167.11 (s, C═O ester), 152.74 (d, C2′), 148.13 (d, C6′), 134.3 (d, C4′), 129.7 (s, C3′), 123.41 (d, C5′), 97.18 (d, ═CH, C4), 61.39 (t, OCH 2 ), 45.66 (t, CH 2 ), 13.93 (q, Me); MS.FAB, m/z 236 (M+1), 235 (M+).
4-Hydroxy-6-(3-pyridyl)-2-pyrone-(5B)
To a flask equipped with an adaptor connecting to a manifold, 0.594 g (2.53 mmol) of ester 13A was added while the flask was maintained under argon. The flask was then connected to a vacuum set at 3 mm Hg pressure and heated over an oil bath at 150° C. The flask was kept at this temperature for 0.5 h and then cooled to room temperature. Diethyl ether was added to the crude product and filtered, washed with diethyl ether. The solid after drying under vacuum gave 0.38 g (89% yield based on recovered starting ester 13A) of 5B. The filtrate was concentrated and column chromatographed to give 0.065 g (10.9% recovery) of starting ester 13A. Compound 5B: mp 187-189° C.; Lit. (Narashimhan, N. S. and Ammanamanchi, R., “Mechanism of acylation of dilithium salts of β-ketoesters: an efficient synthesis of anibine,” J. Org. Chem. (1983) 48:3945-3947) 254-255° C.; 1 H NMR(CDCl 3 and DMSO-d6) δ9.03 (s, 1 H, C2′ H), 8.67 (d, J=5.2Hz, 1 H, C6′ H) pyr ring), 8.13 (d, J=8Hz, 1 H, C4′ H), 7.41 (dd, J=8 Hz, 5.2 Hz, 1 H, C5′ H), 6.56 (d, J=1.6 Hz, 1 H, C3 H), 5.62 (d, J=1.6 Hz, 1 H, C5 H); MS.FAB, m/z 190 (M+1), 189 (M+).
Methyl 5-(3,4-dimethoxyphenyl)-3,5-dioxopentanoate (13B)
To a cold (−20° C.) solution of 8.9 mL (63.7 mmol) of diisopropylamine in 100 mL of diethyl ether under argon was added 28.1 mL (63.7 mmol; 2.27 M solution in hexanes) of n-BuLi via syringe and the solution was stirred at 0° C. for 45 min. In a separated flask, 3.315 g (25.5 mmol) of freshly distilled ethyl acetoacetate and 50 mL of diethyl ether were added and the solution was cooled to −78° C. To it, the above LDA solution was added via cannula, then 3.84 mL (25.5 mmol) of N,N,N′,N′-tetramethylethylenediamine (TMEDA) (distilled from LiAlH 4 ) was added via syringe, and the solution was stirred at 0° C. for 3 h. To this dianion solution, a solution of 5.0 g (25.5 mmol) of methyl 3,4-dimethoxybenzoate in 50 mL of diethyl ether was added via cannula and the reaction solution was warmed to room temperature and stirred for 40 h. The reaction mixture was filtered through fritted funnel, and the solid (desired product) was saved. The organic filtrate from the above filtration was washed with a solution of 50 mL of 1 N HCl and 50 mL of distilled water, and then with 80 mL of brine, dried (MgSO 4 ), and concentrated to give the desired product, 5-(3,4-dimethoxy-phenyl)-3,5-dioxopentanoic acid. The solid obtained above was dissolved in 80 mL of distilled water and 10 mL of 1 N HCl solution, and washed twice with methylene chloride (100 mL each). The water layer was further acidified with 100 mL of 1 N HCl, extracted twice with methylene chloride (50 mL each). The combined methylene chloride extract was washed with 80 mL of brine, dried (MgSO 4 ), concentrated to give the desired carboxylic acid [5-(3,4-dimethoxyphenyl)-3,5-dioxopentanoic acid]. This acid and the above acid from the filtrate were combined and dissolved in 50 mL of CH 2 Cl 2 , cooled over ice-water bath, and a solution of diazomethane in diethyl ether was added dropwise until the carboxylic acid was no longer present. The solution was concentrated on a rotary evaporator and dried under vacuum, and column chromatographed on silica gel using a gradient mixture of hexane and ethyl acetate as eluant to give 3.798 g (56% yield) of pure 13B. 1 H NMR δ7.51 (dd, J=8.5 Hz, 2 Hz, 1 H, C5′ H, Ar), 7.45 (d, J=2 Hz, 1 H, C2′ H), 6.9 (d, J=8.5 Hz, 1 H, C6′ H), 6.24 (s, 1 H, ═CH of enol at C4&5), 3.95 (s, 6 H, 2 OMe on Ar ring), 3.77 (s, 3 H, MeO), 3.47 (s, 2 H, CH 2 ); 13 C NMR δ186.18 (s, C3 C═O), 184.05 (s, C5═C—O), 168.21 (s, C═O ester), 153.16 (s, C4′Ar), 149.07 (s, C3′Ar), 127.04 (s, Cl′Ar), 121.49 (d, C2′), 110.56 (d, C5′), 109.66 (d, C6′), 96.17 (d, C4═CH), 56.06 (q, OMe), 56.0 (q, OMe), 52.32 (q, OMe of ester), 44.89 (t, CH 2 ); MS.FAB, m/z 281 (M+1), 280 (M+).
4-Hydroxy-6-(3,4-dimethoxyphenyl)-2-pyrone (5C)
A flask containing the methyl ester 13B (2.2 g; 7.86 mmol) was connected into a vacuum system to provide −3 mmHg pressure and heated over an oil bath to 160° C. over a one hour period. The reaction was kept at this temperature for another one hour, cooled to room temperature, diluted with a small amount of ether and filtered to collect the yellow solids, washed with ether, and the solids were dried under vacuum to give 1.04 g (70.5% yield based on recovered starting material 13B) of pyrone 5C and 0.534 g (24% recovery) of starting ester 13B. Compound 5C: mp 210-212° C., 1 H NMR δ7.40 (dd, J=8.3 Hz, 2 Hz, 1 H, C6′ of the phenyl ring), 7.33 (d, J=2 Hz, 1 H, C2′ of Ph ring), 6.91 (d, J=8.3 Hz, 1 H, C5′), 6.40 (s, C3 H), 5.55 (s, 1 H, C5 H), 3.95 (s, 3 H, OMe), 3.94 (s, 3 H, OMe); MS.FAB, m/z 249 (M+1), 248 (M+).
cis- and trans-3,5a-Dimethyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]-benzopyran (1B and 1C)
From 0.024 g (0.188 mmol) of aldehyde 4B and 23.7 mg (0.188 mmol) of pyrone 5A, heating with 3 mL of ethyl acetate and 3 drops (˜15 mg) of piperidine and 3 drops of acetic acid at 80° C. for 18 h, 0.033 g (72% yield) of a mixture of 1B and 1C in a ratio of 1.6:1 (obtained from 1 H NMR spectrum) was obtained. Compound 1B: 1 H NMR δ6.13 (d, J=2 Hz, 1 H, C10 H), 5.77 (s, 1 H, C4 H), 4.07 (dd, J=8.4 Hz, 3.4 Hz, 1 H, C5a H), 2.36-2.16 (a series of m, 2 H), 2.21 (s, 3 H, C3 Me), 2.14 (broad s, 1H, OH), 1.98-2.04 (m, 1 H), 1.83-1.76 (m, 1 H), 1.56−1.42 (m, 2 H), 1.47 (s, 3 H, C5a Me); 13 C NMR δ162.42 (s, Cl), 162.08 (s, C4a), 158 (s, C3), 134.17 (s, C10a), 111.67 (d, C10), 100.13 (d, C4),98.08 (s, C9a), 87.07 (s, C5a,), 76.16 (d, C6), 31.59 (t), 30.94 (t), 23.20 (t), 20.36 (q, Me), 17.52 (q, Me); MS.FAB, m/z 249 (M+1), 248 (M+). Compound 1C: 1 H NMR δ6.23 (d, J=3 Hz, 1 H, C10 H), 5.80 (s, 1 H, C4 H), 3.87 (t, J=1 Hz, 1 H, C5a H), 2.21 (s, 3 H, C3 Me), 1.44 (s, 3 H, C5a Me), 2.4-1.5 (a series of m, 6 H); MS.FAB, m/z 249 (M+1), 248 (M+).
3-(3-Pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (2A)
From 0.344 g (1.82 mmol) of pyrone 5B and 0.2 g (1.82 mmol) of aldehyde 4A, 0.373 g (73% yield) of 2A was obtained after column chromatographic separation. IR (Nujol) ν 3070, 1690, 1620, 1540, 1200, 1060, 1020. 1 H NMR δ8.99 (d, J=2 Hz, 1 H, Pyr.), 8.65 (dd, J=4.9 Hz, 2 Hz, 1 H, C6′H), 8.1 (dt, J=8 Hz, 2 Hz, 1 H, C4′H), 7.38 (dd, J=8 Hz, 4.9 Hz, 1 H, C5′H), 6.44 (s, 1 H, C10 H), 6.14 (s, 1 H, C4 H), 5.14 (dd, J=11 Hz, 5 Hz, 1 H, C5a H), 2.47 (m, 1H, C9 H), 2.19 (m, 1 H, C9 H), 2.03 (m, 1 H), 1.94 (m, 1 H), 1.86-1.76 (m, 2 H), 1.5 (dt, J=13 Hz, 3.4 Hz, 1 H), 1.37 (dt, J=13 Hz, 3.4 Hz, 1 H); 13 C NMR δ162.63 (s, Cl), 161.44 (s, C4a), 156.51 (s, C3), 151.22 (d, C2′), 146.73 (d, C6′), 134.94 (s, C3′), 132.84 (d, C4′), 127.56 (s, C10a), 123.73 (d, C5′), 109.22 (d, C10), 99.84 (s, C9a), 98.57 (d, C4), 80.08 (d, C5a), 35.34 (t, C9), 33.38 (t, C6), 27.01 (t, C7), 24.62 (t, C8); MS.FAB, m/z 282 (M+1, 100%), 281 (M+), 252, 202, 148, 136, 106. Anal. Calc. for C 17 H 15 NO 3 : C, 72.58; H, 5.37. Found: C, 72.33; H, 5.42.
3-(3,4-Dimethoxyphenyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (3A)
From 0.2 g (0.81 mmol) of 5C and 0.135 g (0.81 mmol) of aldehyde 4A, 0.20 g (62% yield) of 3A was obtained after column chromatographic separation. Mp. 137-138° C.; IR (Nujol) ν 3010, 3050, 1700, 1650, 1630, 1560, 1520, 1280, 1240, 1150; 1 H NMR δ7.37 (dd, J=8.5 Hz, 2 Hz, 1 H, C6′H, Ph ring), 7.28 (d, J=2 Hz, 1 H, C2′H), 6.9 (d, J=8.5 Hz, 1 H, C5′ H), 6.29 (s, 1 H, C10 H), 6.14 (s, 1 H, C4 H), 5.07 (dd, J=11.4 Hz, 5.2 Hz, 1 H, C5a H), 3.94 (s, 3 H, OMe), 3.93 (s, 3 H, OMe), 2.45 (d, J=14 Hz, 1 H, C9 H), 2.18 (m, 1 H), 2.02 (m, 1 H), 1.92 (m, 1H), 1.78 (m, 2 H), 1.54-1.34 (m, 2 H); 13 C NMR δ163.44 (s, Cl), 161.95 (s, C4a), 159.28 (s, C3), 151.3 (s, C4′, Ph ring), 149.16 (s, C3′), 133.61 (s, Cl′), 124.13 (s, C10a), 118.89 (d, C2′), 111.05 (d, C5′), 109.38 (d, C10), 108.12 (d, C6′), 98.05 (s, C9a), 96.1 (d, C4), 79.75 (d, C5a), 56.12 (q, OMe), 56.04 (q, OMe), 35.25 (t, C9), 33.25 (t, C6), 26.95 (t, C7), 24.58 (t, C8); MS.FAB, m/z 341 (M+1, 100%), 340 (M+), 307, 289, 261, 235, 219. Anal. Calc. for C 20 H 20 O 5 : C,70.58; H, 5.92. Found: C,70.31; H, 6.11.
cis- and trans-3-(3-Pyridyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]-benzopyran (2B and 2C) and cis- and trans-3-(3-pyridyl)-5a-methyl-6-formyloxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-][1]-benzopyran (2D and 2E)
Condensation of 0.073 g (0.39 mmol) of pyrone 5B and 0.065 g (0.39 mmol) of aldehyde 4C in the presence of 0.023 g (0.19 mmol) of L-proline in 5 mL of ethyl acetate under argon at 70° C. was carried out for 3 days and then 3 mL of N,N-dimethylformamide (DMF) was added and the reaction mixture was heated at the same temperature for another 3 days. After aqueous work-up as described in the general procedure, 0.131 g of crude product was obtained. Columnn chromatographic separation of this material afforded 39% yield of formates 2D and 2E (in a ratio of 2:1) and 11% yield of alcohols 2B and 2C (ratio of 2: 1). Compounds 2D and 2E, and 2B and 2C are separable by a careful silica-gel column chromatography to give 34 mg (26% yield) of 2D, 17 mg (13% yield) of 2E, 9 mg (7.3% yield) of 2B, and 4 mg (3.7% yield) of 2C. Compounds 2B and 2C were probably formed from the hydrolytic reaction with trace amount of H 2 O contained in DMF.
Compound 2D: Mp. 160-161° C.; 1 H NMR δ9.0 (d, J=2 Hz, 1 H, C2′ H, pyr.), 8.66 (dd, J=5 Hz, 2 Hz, 1 H, C6′H), 8.18 (s, 1 H, CHO), 8.09 (dt, J=8 Hz, 2 Hz, 1 H, C4′H), 7.39 (dd, J=8 Hz, 5 Hz, 1 H, C5′H), 6.46 (s, 1 H, C10H), 6.26 (s, 1 H, C4H), 5.38 (dd, J=12 Hz, 5 Hz, 1 H, C6H), 2.42 (m, 1 H, C9H), 2.3 (m, 1 H, C9H), 2.12 (m, 1 H), 1.88 (m, 1 H), 1.7-1.52 (m, 2 H), 1.60 (s, 3 H, Me); 13 C NMR δ161.5 (s, Cl), 160.14 (d, s, 2 C, CHO & C4a), 157.12 (s, C3), 151.33 (d, C2′, pyr.), 146.72 (d, C4′), 134.2 (d, C3′), 132.8 (d, C4′), 127.31 (s, C10a), 123.6 (d, C5′), 112.25 (d, C10), 99.82 (s, C9a), 98.5 (d, C4), 84.61 (s, C5a), 76.18 (d, C6), 31.25 (t, C9), 29.07 (t, C7), 22.85 (t, C8), 18.85 (q, Me); MS.FAB, m/z 340 (M+1, 100%), 293, 278, 266, 240, 202, 173. Anal. Calc. for C 19 H 17 NO 5 : C, 67.25; H, 5.05. Found: C, 67.07; H, 5.29.
Compound 2E: 1 H NMR δ9.0 (d, J=2 Hz, 1 H, C2′H, pyr.), 8.66 (dd, J=5 Hz, 2 Hz, 1 H, C6′H), 8.14 (s, 1 H, CHO), 8.10 (dt, J=8 Hz, 2 Hz, 1 H, C4′H), 7.39 (dd, J=8 Hz, 5 Hz, 1 H, C5′H), 6.45 (s, 1 H, C10H), 6.31 (s, 1 H, C4H), 5.28 (broad s, 1 H, C6H), 2.46-1.5 (a series of m, 6 H), 1.64 (s, 3 H, Me); MS.FAB, m/z 340 (M+1, 100%).
Compound 2B: 1 H NMR δ9.0 (d, J=2 Hz, 1 H, C2′H, pyr.), 8.66 (d, J=4 Hz, 1 H, C6′H), 8.10 (dt, J=8 Hz, 2 Hz, 1 H, C4′H), 7.39 (dd, J=8 Hz, 4 Hz, 1 H, C5′H), 6.51 (s, 1 H, C10H), 6.20 (d, J=2 Hz, 1 H, C4H), 4.14 (dd, J=12 Hz, 4.4 Hz, 1 H, C6H), 2.42-1.4 (a series of m, 6 H), 1.54 (s, 3 H, Me); Anal. Calc. for C 18 H 17 NO 4 : C, 69.44; H, 5.50. Found: C, 69,17; H, 5.21.
Compound 2C: 1 H NMR δ9.0 (d, J=2 Hz, 1 H, C2′H, pyr.), 8.66 (d, J=4 Hz, 1 H, C6′H), 8.10 (dt, J=8 Hz, 2 Hz, 1 H, C4′H), 7.39 (dd, J=8 Hz, 4 Hz, 1 H, C5′H), 6.32 (s, 1 H, C10H), 6.20 (d, J=2 Hz, 1 H, C4H), 3.94 (broad s, 1 H, C6H), 2.42-1.4 (a series of m, 6 H), 1.51 (s, 3 H, Me); MS.FAB, m/z 312 (M+1, 100%).
cis- and trans-3-(3,4-Dimethoxyphenyl)-5a-methyl-6-hydroxy-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]-benzopyran (3B and 3C)
Condensation of 0.103 g (0.41 mmol) of pyrone 5C and 0.058 g (0.41 mmol) of hydroxy aldehyde 4B gave 3B and 3C in a ratio of 2:1. Column chromatographic separation gave pure 3B and 3C.
Compound 3B: 1 H NMR δ7.39 (dd, J=8 Hz, 2 Hz, 1 H, C6′, Ph), 7.29 (d, J=2 Hz, C2′H), 6.9 (d, J=8 Hz, 1 H, C5′H), 6.37 (s, 1 H, C10H), 6.2 (d, J=2 Hz, 1 H, C4H), 4.12 (dd, J=12 Hz, 5 Hz, 1 H, C6H), 3.94 (s, 3 H, OMe), 3.93 (s, 3 H, OMe), 2.36 (m, 1 H), 2.26 (m, 1 H) 2.04 (m, 1 H), 1.82 (m, 1 H), 1.6-1.46 (m, 2 H), 1.51 (s, 3 H, Me); MS.FAB, m/z 371 (M+1, 100%), 3.70 (M+), 355, 325, 307, 261, 219, 207. Anal. Calc. for C 12 H 22 O 6 : C, 68.10; H, 5.99. Found: C, 67.89; H, 5.73.
Compound 3C: 1 H NMR δ7.38 (dd, J=8 Hz, 2 Hz, 1 H, C6′, Ph), 7.29 (d, J=2 Hz, C2′H), 6.9 (d, J=8 Hz, 1 H, C5′H), 6.37 (s, 1 H, C10H), 6.31 (d, J=2 Hz, 1 H, C4H), 3.92 (m, 1 H, C6H), 3.94 (s, 3 H, OMe), 3.93 (s, 3 H, OMe), 2.53 (broad s, 1 H, OH), 2.42 (m, 1 H), 2.3 (m, 1 H), 2.08 (m, 1 H), 1.88 (m, 1 H), 1.77 (m, 1 H), 1.58 (m, 1 H), 1.49 (s, 3 H, Me); 13 C NMR δ162.29 (s, Cl), 161.6 (s, C4a), 159.52 (s, C3), 151.4 (C4′, Ph), 149.19 (s, C3′), 133.87 (s, Cl′), 124.01 (s, C10a), 118.9 (d, C2′), 112.65 (d, C5′), 111.04 (d, C10), 108.17 (d, C6′), 99.07 (s, C9a), 96.18 (d, C4), 85.62 (s, C5a), 73.07 (d, C6), 56.10 (q, OMe), 55.99 (q, OMe), 31.21 (t, C9), C7), 22.62 (t, C8), 19.56 (q, Me); MS.FAB, m/z 371 (M+1, 100%), 370 (M+).
cis- and trans-3-(3,4-Dimethoxyphenyl)-6-formyloxy-5a-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]-benzopyran (3D and 3E)
From 0.062 g (0.25 mmol) of pyrone 5C and 0.042 g (0.25 mmol) of aldehyde 4C, 48 mg (48% yield) of a 2:1 mixture of formyloxy derivatives 3D and 3E, and 22 mg (24% yield) of a 2:1 mixture of alcohol 3B and 3C were obtained after column chromatographic separation.
Compound 3D: IR (Nujol) ν 3080, 1690 (s, C═O), 1640, 1610, 1595, 1535, 1485, 1310, 1255, 1170, 1130, 1010, 970, 955, 845, 790; 1 H NMR δ8.20 (s, 1H, CHO), 7.40 (dd, J=8 Hz, 2 Hz, 1 H, C6′H,Ph), 7.27 (d, J=2 Hz, 1 H, C2′H), 6.90 (d, J=8 Hz, 1 H, C5′H), 6.32 (s, 1 H, C10H), 6.24 (d, J=2 Hz, 1 H, C4H), 5.34 (dd, J=12 Hz, 4.6 Hz, 1 H, C6H), 3.94 (s, 3 H, OMe), 3.92 (s, 3 H, OMe), 2.4-1.5 (a series of m, 6 H), 1.58 (q, Me); 13 C NMR 8 [from a 2:1 ratio mixture of 3D (c) and 3E (t)] 162.28 (Cl, t), 162.08 (Cl,c), 161.33 (C4a, t), 161.23 (C4a, c), 160.09 (CHO, c), 159.98 (CHO, t), 159.65 (C3, c), 159.40 (C3, t), 151.19 (C4′, c), 151.14 (C4′, t), 148.88 (C3′, c & t), 132.72 (Cl′, c), 131.79 (Cl′, t), 123.65 (C10a, c & t), 118.80 (C2′, c), 118.73 (C2′, t), 112.24 (C5′, c), 112.12 (C5′, t), 110.77 (C0, c & t), 107.84 (C6′, c), 107.77 (C6′, t), 97.87 (C9a, c), 97.45 (C9a, t), 95.85 (C4, c), 95.69 (C4, t), 83.98 (C5a, c), 82.67 (C5a, t), 76.23 (C6, c), 73.97 (C6, t), 56.83 (OMe, c & t), 55.74 (OMe, c& t), 30.91 (C9, c), 30.81 (C9, t), 28.82 (C7, c), 27.67 (C7, t), 22.65 (C8, c), 20.36 (C8, t), 18.46 (Me, c & t); MS.FAB, m/z 399 (M+1, 80%), 398 (M+), 352 (90%), 261, 165 (100%), 136.
Compound 3E (pure): 1 H NMR δ8.15 (s, 1 H, CHO), 7.40 (dd, J=8 Hz, 2 Hz, 1 H, C6′H, Ph), 7.27 (d, J=2 Hz, 1 H, C2′H), 6.90 (d, J=8 Hz, 1 H, C5′H), 6.32 (s, 1 H, C10H), 6.29 (s, 1 H,C4H), 5.28 (s, 1 H, C6H), 3.94 (s, 3 H, OMe), 3.92 (s, 3 H, OMe), 2.4-1.5 (a series of 1.62 (q, Me); MS.FAB, m/z 399 (M+1, 80%), 398 (M+).
Synthesis of 1H-6,7,8,9-tetrahydro-1-oxopyrano[4,3-b]quinoline (24) and 1H-3-methyl-7,8,9,10-tetrahydropyrano[4,3-c]isoquinolin-1-one (26) by Scheme 8
A mixture of 0.190 g (1.52 mmol) of pyrone 20, 250 mg (2.28 mmol) of aldehyde 4A, and 35 mg (0.15 mmol) of(S)-(+)-10-camphorsulfonic acid in 12 mL of toluene was heated at 85° C. for 3 days under argon atmosphere. The mixture was cooled to room temperature, filtered, and washed with 20 mL of ethyl acetate. The filtrate was diluted with 100 mL of methylene chloride, washed with 50 mL of water, and 50 mL of brine, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using ethyl acetate:hexane (2:1) as eluant to give 13.3 mg (19% yield; based on unrecovered starting material) of 24, 33 mg (48% yield) of 26, and 150 mg (79% recovery) of pyrone 20. Pyrone 20 can be reused under similar reaction conditions to provide more materials of 24 and 26.
Compound 24: white solids, mp 71-72° C.; 1 H NMR (CDCl 3 ) δ8.15 (s, 1 H, C10H), 6.44 (s, 1 H, C4 H), 3.01 (t, J=7 Hz, 2 H, CH 2 ), 2.88 (t, J=7 Hz, 2 H, CH 2 ), 2.31 (s, 3 H, Me), 1.95 (m, 2 H, CH 2 ), 1.86 (m, 2 H, CH 2 ); 13 C NMR (CDCl 3 ) δ168 (s, Cl), 165.71 (s, C5 a), 157.69 (s, C4a), 152.22 (s, C3), 137.2 (d, C10), 132.34 (s, C10a), 114.0 (s, C9a), 105.48 (d, C4), 33.34 (t, CH 2 ), 28.69 (t, CH 2 ), 22.59 (t, CH 2 ), 22.32 (t, CH 2 ), 19.89 (q, Me); MS (FAB) 216 (M+1). The structure was unequivocally determined by a single-crystal X-ray analysis.
Compound 26: white solids, mp 73-74° C.; 1 H NMR (CDCl 3 ) δ8.50 (s, 1 H, C10H), 6.43 (s, 1 H, C4 H), 3.35 (t, J=6 Hz, 2 H, CH 2 ), 2.82 (t, J=6 Hz, 2 H, CH 2 ), 2.29 (s, 3 H, Me), 1.90-1.80 (m, 4 H, CH 2 ); 13 C NMR (CDCl 3 ) δ162.5 (s, Cl), 157.4 (s), 156.4 (d, C6), 154.4 (s), 151.4 (s), 132.7 (s), 114.6 (s), 106.5 (d, C4), 28.6 (t, CH 2 ), 27.6 (t, CH 2 ), 22.6 (t, CH 2 ), 21.7 (t, CH 2 ), 19.8 (q, Me); MS (FAB) 216 (M+1), 215, 188, 154, 136. The structure was unequivocally determined by a single-crystal X-ray analysis.
(5aS, 7S)-7-Isopropenyl-3-methyl-1H-5a,6,7,8,9-pentahydyro-1-oxopyrano[4,3-][1]benzopyran (28)
From 1.000 g (7.93 mmol) of 5A and 1.191 g (7.93 mmol) of aldehyde (S)-27, 1.596 g (78% yield) of 28 was obtained after column chromatographic separation; yellow solids, mp 140-141° C. [α] D 22 =+31.9° (c 0.75, CHCl 3 ); 1 H NMR δ6.1 (s, 1 H, C10 H), 5.72 (s, 1 H, C4 H), 4.1 (dd, J=11 Hz, 5 Hz, 1 H, C5a H), 4.75 (m, 1 H, ═CH), 4.73 (m, 1 H, ═CH), 2.48 (ddd, J=14 Hz, 4 Hz, 2.4 Hz, 1 H), 2.22-2.02 (series of m, 3 H), 2.19 (s, 3 H, C4-Me), 1.88-1.72 (series of m, 2 H), 1.74 (s, 3 H, Me—C═), 1.31 (ddd, J=25 Hz, 12.8 Hz, 4Hz, 1 H); 13 C NMR δ163.4 (s, C═O), 162.6 (s, C3), 161.7 (s, C4a), 147.9 (s, C10a), 132.3 (s, =C), 109.8 (d, C10), 109.6 (t, ═CH 2 ), 99.9 (d, C4), 97.5 (s, C9a), 79.4 (s, C5a), 43.6 (d, C7), 40.0 (t), 32.5 (t), 32.1 (t), 20.9 (q, Me), 20.3 (q, Me); MS. FAB, m/z 259 (M+1; 70%), 258, 257, 215, 189, 139 (100%); Anal. Calc. for C 16 H 18 O 3 : C, 74.40; H, 7.02. Found: C, 74.17; H, 7.33.
(5aS,7S)-7-Isopropenyl-3-(3-pyridyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-][1]benzopyran (29)
From 0.200 g (1.06 mmol) of 5B and 0.160 g (1.06 mmol) of aldehyde (S)-27, 0.221 g (65% yield) of 29 was obtained after column chromatographic separation; yellow solids, mp 99-100° C. [α] D 22 =+100.6° (c 0.77, CH 2 Cl 2 ); 1 H NMR δ8.98 (d, J=2 Hz, 1 H, C2′ H, Pyr.) 8.65 (dd, J=4.8 Hz, 2 Hz, 1 H, C6′H), 8.07 (dt, J=8 Hz, 2 Hz, 1 H, C4′H), 7.38 (dd, J=8 Hz, 4.8 Hz, 1 H, C5′H), 6.44 (s, 1H, C10 H), 6.15 (s, 1 H, C4 H), 5.17 (dd, J=11.6 Hz, 5.2 Hz, 1 H, C5a H), 4.74 (m, 2 H, ═CH 2 ), 2.52 (m, 1 H), 2.26-1.75 (a series of m, 5 H), 1.75 (s, 3 H, Me), 1.3 (m, 1 H); 13 C NMR δ162.5 (s, Cl), 161.3 (s, C4a), 156.6 (s, C3), 151.2 (d, C2′), 147.6 (d, C6′), 146.7 (s, C═), 133.9 (s, C3′), 132.7 (d, C4′), 127.4 (s, C10a), 123.7 (d, C5′), 109.9 (d, C10), 109.4 (t, ═CH 2 ), 99.8 (s, C9a), 98.4 (d, C4), 79.6 (d, C5a), 43.4 (d, C7), 39.9 (t), 32.5 (t), 31.9 (t), 20.8 (q, Me); MS. FAB, m/z 322 (M+1, 100%), 278 (M+), 252, 202, 148, 106. Anal. Calc. for C 20 H 19 NO 3 : C, 74.75; H, 5.96. Found: C, 74.48; H, 6.12.
(5aS, 7S)-7-Isopropenyl-3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8 9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (30)
From 0.200 g (0.81 mmol) of 5C and 0.121 g (0.81 mmol) of aldehyde (S)-27, 0.193 g (63% yield) of 30 was obtained after column chromatographic separation; yellow solids, mp 119-120° C. [α] D 22 =+90.4° (c 0.76, CHCl 3 ); 1 H NMR δ7.37 (dd, J=8.8 Hz, 2.4 Hz, 1 H, C6′ H, Ph ring), 7.28 (d, J=2.4 Hz, 1 H, C2′ H), 6.89 (d, J=8.8 Hz, 1 H, C5′ H), 6.29 (s, 1 H, C10 H), 6.17 (s, 1 H, C4 H), 5.15 (dd, J=11 Hz, 5 Hz, 1 H, C5a H), 4.75 (m, 2H, ═CH 2 ), 3.94 (s, 3 H, OMe), 3.92 (s, 3 H, OMe), 2.52 (ddd, J=13 Hz, 6 Hz, 3.6 Hz, 1 H), 2.26-2.24 (a series of m, 3 H), 1.88-1.76 (m, 2 H), 1.75 (s, 3 H, Me), 1.34 (m, 1 H); 13 C NMR δ163.6 (s, Cl), 162.1 (s, C4a), 159.7 (s, C3), 151.6 (s, C4′), 149.4 (s, C3′), 148.0 (s, ═C), 132.8 (s, Cl′), 124.3 (s, C10a), 119.1 (d, C2′), 111.3 (d, C5′), 109.9 (d, ═CH 2 ), 109.9 (d, C10), 108.84 (d, C6′), 98.3 (s, C9a), 96.2 (d, C4), 79.5 (d, C5a), 56.3 (q, OMe), 56.2 (q, OMe), 43.6 (d, C7), 40.1 (t), 32.6 (t), 32.1 (t), 20.9 (q, Me); MS. FAB, m/z 381 (M+1, 100%), 380 (M+). Anal. Calc. for C 23 H 24 O 5 : C, 72.61; H, 6.36. Found: C, 72.43; H, 6.17.
3-(Methoxycarbonylmethyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (31)
To a cold (−78° C.) solution of 0.4 g (1.83 mmol) of pyrone 1A in 10 mL of THF under argon was added a cold (0° C.) solution of LDA [freshly prepared from 0.31 mL (2.2 mmol) of diisopropylamine and 1.4 mL (2.2 mmol; 1.6 M in hexane) of n-BuLi in 10 mL of ether under argon at −10° C. for 1 h]. To the reaction solution, 0.32 mL (1.83 mmol) of HMPA (hexamethylphosphoramide) was added, the resulting solution was stirred at −78° C. for 3 h, and then 0.14 mL (1.83 mmol) of methyl chloroformate was added. After the solution was stirred at room temperature for 16 h, it was diluted with 20 mL of water, and extracted with 50 mL of methylene chloride. The methylene chloride extract was dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using a gradient mixture of hexane and ether as eluant to give 0.215 g (72% yield; based on recovered starting material) of 31 and 0.165 g (41% recovery) of pyrone 1A. Compound 31: 1 H NMR δ6.1 (s, 1 H, C4 H), 6.06 (s, 1 H, C10 H), 5.06 (dd, J=11, 5 Hz, 1 H, C5a H), 3.81 (s, 2 H, CH 2 ), 3.80 (s, 3 H, OMe), 2.43 (m, 1 H), 1.98-1.74 (m, 5 H), 1.54-1.3 (m, 2 H); 13 C NMR δ165.2 (s, C═O), 162.3 (s, C═O), 161.4 (s, C3), 153.8 (s, C4a), 134.7 (s, C10a), 108.9 (d, C10), 102.6 (d, C4), 99.5 (s, C9a), 80.1 (s, C5a), 56.0 (q, OMe), 53.6 (t, CH 2 ), 35.3 (t), 33.3 (t), 27.0 (t), 24.5 (t).
3-(Carboxylmethyl)-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (32)
A solution of 0.08 g (0.29 mmol) of ester 31 and 0.033 g (0.58 mmol) of KOH in 4 mL of THF-H 2 O (1:3) was stirred at 40° C. for 30 h, cooled to room temperature, diluted with 30 mL of distilled water, and extracted with 40 mL of diethyl ether and then with 40 mL of methylene chloride. The combined extracts were washed with 30 mL of water, and with 30 mL of brine, dried (MgSO 4 ), concentrated to give 20.5 mg (26% recovery) of starting material 31. The combined aqueous layers were acidified with 1 N HCl, and extracted three times with 50 mL-portion of methylene chloride. The combined extract was washed twice with water (40 mL each), with 40 mL of brine, dried (MgSO 4 ), concentrated to give 32.5 mg (58% yield; based on recovered starting material) of 32. 1 H NMR δ6.8 (broad s, 1 H, OH), 6.04 (s, 1 H, C10 H), 5.96 (s, 1 H, C4 H), 5.07 (dd, J=11, 5 Hz, 1 H, C5a H), 3.51 (s, 2 H, CH 2 ), 2.42 (dd, J=14 Hz, 2 Hz, 1 H), 2.2-1.7 (m, 5H), 1.5-1.2 (m, 2 H).
1,8-Di-{3-[1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyranyl]}-2,7-octanedione (33)
The reaction conditions are similar to those of the preparation of 31. From 0.40 g (1.83 mmol) of pyrone 1A, 2.2 mmol of LDA, 1.83 mmol of HMPA, and 0.13 mL (0.5 equiv.; 0.9 mmol) of adipoyl chloride in 10 mL of THF and 10 mL of ether gave 0.091 g (38% yield; based on recovered starting material) of 33 and 0.18 g (45% recovery) of starting material 1A after column chromatography.
Compound 33: Mp. 161-162° C.; 1 H NMR δ6.39 (s, 2 H, ═CH of enol of the side chain), 6.07 (s, 2 H, C10 H), 5.64 (s, 2 H, C4 H), 5.04 (dd,J-11, 5 Hz, 2 H, C5a H), 2.6-1.3 (m, 24 H); 13 C NMR δ170.4 (s, C—O of enol), 162.9 (s, C═O), 161.6 (s, C3), 156.1 (d, ═CH of enol), 154.7 (s, C4a), 134.6 (s, C10a), 109.3 an 109.2 (d, C10), 102.3 (d, C4), 99.4 (s, C9a), 79.8 (s, C5a), 35.3 (t), 34.6 (t), 33.3 (t), 28.9 (t), 27.0 (t), 24.6 (t), 22.8 (t).
(5aS,7S)-7-[2-(1-Hydroxypropyl)]-3-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (34)
To a cold (−20° C.) solution of 0.10 g (0.39 mmol) of pyrone 28 in 3 mL of THF under argon was added a solution of 0.39 mL (0.39 mmol) of BH 3 .THF (1.0 M in THF). After the solution was stirred at −20° C. for 1 h, and −15° C. for 1 h, 2 mL of 1% aqueous NaOH and 1.5 mL of 30% H 2 O 2 were added, and resulting solution was stirred at 25° C. for 3 h. The reaction mixture was diluted with 20 mL of distilled water, extracted three times with methylene chloride (40, 30, and 20 mL), and the combined extracts were washed with 30 mL of brine, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using a gradient mixture of hexane and ether as eluant to give 0.074 g (69% yield) of alcohols 34 as a 1:1 mixture of two diastereomers at C-12: 1 H NMR δ6.05 (s, 1 H, C10 H), 5.72 (s, 1 H, C4 H), 5.07 (m, 1 H, C5a H), 3.58 (ddd, J=11 Hz, 6 Hz, 3 Hz, 1 H, CHO), 3.54 (dd, J=11 Hz, 6 Hz, 1 H, CHO), 2.46 (d, J=12 Hz, 1 H), 2.19 (s, 3 H, Me), 2.18-1.3 (series of m, 7 H), 0.906 (d, J =6.8 Hz, 3 H, Me), 0.902 (d, J=6.8 Hz, 3 H, Me); 13 C NMR δ163.5 (s, C═O), 162.8 (s, C3), 161.6 (s, C4a), 133.0 (s, C10 a), 109.1 (d, C10), 100.0 (d, C4), 97.5 (s, C9a), 79.8 and 79.7 (s, C5a; 2 isomers), 65.71 and 65.69 (t, CH 2 O, 2 isomers), 40.1 and 39.4 (t), 37.4, 37.3, 37.0, 32.5, 32.4, 31.2, 28.6, 20.2 (q, Me), 13.3 and 13.2 (q, Me).
(5aS,7S)-7-[1-(Formyl)ethyl)]-3-methyl-1H-5a,6,7,8,9-pentahydro-1-oxopyrano[4,3-b][1]benzopyran (35)
A solution of 0.07 g (0.25 mmol) of alcohols 34 and 0.16 g (0.38 mmol) of 1,1,1-triacetoxy-1,1-dihydro-1,2-benziodoxol-3(1H)-one in 4 mL of methylene chloride was stirred at 25° C. under argon for 48 h. The mixture was filtered through Celite, washed with 50 mL of methylene chloride, and the filtrate was concentrated and column chromatographed on silica gel using a gradient mixture of hexane and ether as eluant to give 0.060 g (87% yield) of the desired aldehyde 35 as a mixture of two diastereomers; 1:1 (indicated by proton and carbon NMR spectra). 1 H NMR δ9.68 (d, J=0.8 Hz, 1 H, CHO), 6.09 (s, 1 H, C10 H), 5.71 (s, 1 H, C4 H), 5.1 (m, 1 H, C5a H), 2.47 (d, J=12 Hz, 1 H), 2.35 (m, 1 H, C12 H), 2.19 (s, 3 H, Me), 2.18-1.2 (series of m, 6 H), 1.10 (d, J=6.8 Hz, 3 H, Me); 13 C NMR δ204.14 and 204.1 (d, CHO), 163.29 and 163.27 (s, C═O), 162.5 (s, C3), 161.8 (s, C4a), 141.7 (s, C10a), 109.9 (d, C10), 99.8 (d, C4), 97.4 (s, C9a), 79.03 and 78.9 (s, C5a; 2 isomers), 50.79 and 50.73, 39.2 (t), 37.3, 36.3 and 36.2, 32.2 and 32.1, 31.2, 29.2, 20.2 (q, Me), 10.2 and 10.1 (q, Me).
(5aS,7S,10S)-7-[2-(1-Hydroxylpropyl)]-10-hydroxy-3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9,9a, 10-heptahydro-1-oxopyrano[4,3-b][1]benzopyran (36)
To a cold (−20° C.) solution of 0.120 g (0.31 mmol) of pyrone 30 in 5 mL of THF under argon was added 1 mL (1 mol) of BH 3 .THF (1 M in THF). After the solution was stirred at −20° C. for 30 min., 0° C. for 2 h, and 25° C. for 12 h, 2 mL of 1% NaOH and 2 mL of 30% H 2 O 2 were added, and the resulting solution was stirred at room temperature for 3 h. The reaction solution was diluted with 20 mL of distilled water, extracted three times with methylene chloride (40, 30 and 20 mL), and the combined extract was washed with 40 mL of brine, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using hexane, ether, and ethyl acetate as eluants to give 0.021 g (16% yield) of diol 36 as a 1:1 mixture of two diastereomers at C11: [α] D 22 =−7.4° (c=0.68, CHCl 3 ); 1 H NMR δ7.39 (dd, J=8.8 Hz, 2.4 Hz, 1 H, C6′ H, Ph ring), 7.28 (d, J=2.4 Hz, 1 H, C2′ H), 6.91 (d, J=8.8 Hz, 1 H, C5′ H), 6.33 and 6.328 (two s, 1 H, C10 H; 2 isomers), 4.73 (dd, J=9 Hz, 3.3 Hz, 1 H, C5a H), 4.5 (m, 1 H, C10 H), 4.34 (broad s, 1 H, OH), 3.95 (s, 3 H, OMe), 3.93 (s, 3 H, OMe), 3.6 (m, 2H, CH 2 O), 2.3-2.17 (m, 2 H), 1.85-1.3 (a series of m, 7 H), 0.92 and 0.91 (2 d, J=7 Hz, 3 H, Me; 2 diastereomers); 13 C NMR δ165.0 (s, C1), 164.5 (s, C4a), 151.8 (s, C3), 149.5 (s, C4′), 142 (s, C3′), 124.0 (s, C1′), 119.3 (s, C10a), 111.3 (d, C2′), 108.5 (d, C5′), 100.3 (d, C6′), 97.1 (d, C4), 66.1, 66.1, 56.4 (q, OMe), 56.3 (q, OMe), 39.7, 38.3, 38.2, 31.9, 24.6, 13.8 (q, Me).
(5aS,7S,10S)-7-[2-(1-Pentanoyloxypropyl)]-10-hydroxy-3-(3,4-dimethoxyphenyl)-1H-5a,6,7,8,9,9a,10-heptahydro-1-oxopyrano[4,3-b][1]benzopyran (37)
A solution of 0.014 g (0.034 mmol) of alcohol 36, 4 mg (0.034 mmol) of valeryl chloride, and 0.03 mL (0.34 mmol) of pyridine in 1 mL of methylene chloride was stirred under argon at room temperature for 14 h. A solution of 7 mg of valeryl chloride in 0.2 mL of methylene chloride was added and the solution was stirred at 50° C. for 20 h. The progress of the reaction was monitored by TLC, and 0.015 g of veleryl chloride was added. After 10 min of stirring, the reaction was quenched by adding 20 mL of methylene chloride, washed with 15 mL of saturated aqueous NaHCO 3 . The aqueous layer was extracted twice with methylene chloride (15 and 10 mL). The combined extracts were washed with 20 mL of brine, dried (MgSO 4 ), concentrated and column chromatographed on silica gel using a gradient mixture of hexane and ether as eluant to give 9 mg (53% yield) of ester 37 as a 1:1 mixture of 2 diastereomers at C11(A & B); 1 H NMR δ7.44 (dd, J=8.4 Hz, 2 Hz, 1 H, C6′ H, Ph ring; isomer A), 7.41 (dd, J=8.4 Hz, 2 Hz, 1 H, C6′ H, Ph ring; isomer B), 7.32 (d, J=8.4 Hz, 1 H, C5′ H), 6.39 and 6.27 (two s, 1 H, C10 H; 2 isomers), 5.84 (broad s, 1 H, OH of A), 5.75 (broad s, 1 H, OH of B), 4.45 (m, 1 H, C5a H), 4.32 (m, 1 H, C10 H), 4.06-3.99 (m, 2 H, CH 2 O), 3.96 (s, 3 H, OMe of A), 3.95 (s, 3 H, OMe of B), 3.94 (s, 6 H, 2 OMe of A & B), 2.4-1.0 (a series ofm, 15 H), 0.96-0.90 (t & d, 6 H, 2 Me; 2 diastereomers).
(5aS*,9aS*,10S*)-9a,10-Epoxy-3-(3-pyridyl)-1H-5a,6,7,8,9a, 10-heptahydro-1-oxopyrano[4,3-b][1]benzopyran (38A) and (5aS*,9aR *,10R*)-9a,10-Dihydroxy-3-(3-pyridyl)-1H-5a,6,7,8,9,9a,10-heptahydro-1oxopyrano[4,3-b][1]benzopyran (38B)
To a cold (0° C.) solution of 90 mg (0.3 mmol) of pyrone 2A in 5 mL of methylene chloride under argon was added 0.3 mL (0.3 mmol) of a solution of HCl in ether (1 M). The solution was stirred for 10 min., warmed to room temperature and 0.102 g (0.32 mmol) of m-chloroperbenzoic acid (MCPBA; 55% pure) was added. After two hours of stirring, the mixture was neutralized with 1 M aqueous NaOH, and extracted with 20 mL of CH 2 Cl 2 . The extract was dried (MgSO 4 ), concentrated and column chromatographed on silica gel using ether as eluant to give 7 mg (7% yield) of epoxide 38A and 29 mg (30% yield) of dihydroxide 38B.
Compound 38A: 1 H NMR δ9.03 (s, 1 H, C2′ H, Pyr.), 8.7 (s, 1 H, C6′ H), 8.13 (dt, J=8 Hz, 2 Hz, 1 H, C4′ H), 7.42 (dd, J=8 Hz, 4.9 Hz, 1 H, C5′ H), 6.51 (s, 1 H, C4 H), 5.11 (s, 1 H, C10 H), 4.52 (dd, J=12 Hz, 5 Hz, 1 H, C5a H), 2.43 (m, 1 H), 2.15-1.4 (a series of m, 7 H).
Compound 38B: 1 H NMR δ9.03 (s, 1 H, C2′ H, Pyr.), 8.72 (s, 1 H, C6′ H), 8.14 (dt, J=8 Hz, 2 Hz, 1 H, C4′ H), 7.42 (dd, J=8 Hz, 4.9 Hz, 1 H, C5′ H), 6.51 (s, 1 H, C4 H), 5.04 (s, 1 H, C10 H), 4.81 (s, 1 H, C5a H), 2.3-1.2 (a series of m, 8 H). MS (FAB) m/z: 316 (M+1).
(5R,6S)-2,6-dimethyl-6-(cis-3-iodo-2-propenyl)-5-isopropenyl-2-cylohexen-1-one (41)
To a cold (−40° C.) solution of 46 mL (21 numol) of LDA (prepared as mentioned above from 2.9 mL of diisopropylamine and 13 mL of n-BuLi in 30 mL of THF) under argon was added a solution of 1.69 g (10.3 mmol) of (5R,6S)-2,6-dimethyl-5-isopropenyl-2-cyclohexen-1-one in 30 mL of ether was added via cannula, and the resulting solution was stirred at 0° C. for 45 min. To it, 1.8 mL (10 mmol) of HMPA was added, stirred at the same temperature for 4 hours, and a solution of 5.68 g (22 mmol) of (cis-3-iodo-2-propenyl) methanesulfonate (40) 2 in 30 mL of ether was added. After stirring at room temperature for 12 hours, the reaction mixture was poured into an aqueous solution of NaHCO 3 , extracted three times with ether, and the combined extracts were washed with brine, dried (MgSO 4 ), and concentrated. The residue was column chromatographed on silica gel using a hexane:methylene chloride (3:2) as eluant to give 2.48 g (73% yield) of 41 and 0.237 g (14% recovery) of the starting material.
Compound 41: [α] D 22 =−31.9° (c=1.5, CHCl 3 ); 1 H NMR δ6.63 (m, 1 H, C3 H), 6.3 (dt, J=8 Hz, 1.6 Hz, 1 H, ═CH—I), 6.12 (dt, J=8 Hz, 6.4 Hz, 1 H, ═CH), 4.83.(s, 1 H, ═CH 2 ), 4.74 (s, 1 H, ═CH 2 ), 2.7-2.3 (a series of m, 5 H), 1.79 (s, 3 H, ═C—Me), 1.65 (s, 3 H, ═C—Me), 1.09 (s, 3 H, Me); 13 C NMR δ203.4 (s, C1), 145.8 (s, ═C), 142.4 (d, ═CH), 137.7 (d, ═CH), 134.2 (s, ═C), 114.8 (t, ═CH 2 ), 84.9 (d, CH—I), 50.5 (d, C5), 48.0 (s, C6), 42.8 (t), 29.2 (t), 22.5 (q, Me), 19.3 (q, Me), 16.6 (q, Me).
(4aS,5R,8aS)-Methyl-(1H)-1-Oxo-4,4a,5,8,8a-pentahydro-2,5,8a-trimethylnaphthalene-5-acetate (42) and (4aS,5S,8aS)-Methyl-(1H)-1-Oxo-4,4a,5,8,8a-pentahydro-2,5,8a-trimethyl-naphthalene-5-acetate (47)
A mixture of 0.387 g (1.72 mmol) of Pd(OAc) 2 and 0.904 g (3.44 mmol of Ph 3 P in 10 mL of DMF under argon was stirred at room temperature for one hour. To it, a solution of 0.569 g (1.72 mmol) of iodide 41 in 10 mL of DMF was added via cannula, and the mixture was stirred at 32° C. for 30 min. After 10 mL of MeOH was added, the mixture was maintained under 1 atmosphere of CO (a CO balloon was used), and 0.476 g (1.72 mmol) for Ag 2 CO 3 was added. After stirring at 32° C. for 15 hours, the mixture was cooled to room temperature, filtered, washed the solids with methylene chloride, and the filtrate was concentrated. The residue was dissolved in either and washed with brined, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using a hexane:ether (10: 1) as eluant to give 0.332 g (73% yield) of a mixture of 2.2:1 of 42 and 47.
Pure compound 47: 1 H NMR δ6.77 (m, 1 H, C3 H), 5.68 (ddd, J=10 Hz, 5.6 Hz, 2 Hz, 1 H, C7 H), 5.56 (dd, J=10 Hz, 2 Hz, 1 H, C6 H), 3.67 (s, 3 H, OMe), 2.62 (d, J=13 Hz, 1 H, CH 2 CO 2 ), 2.36 (m, 1 H), 2.31 (d, J=13 Hz, 1 H, CH 2 CO 2 ), 2.28 (m, 2 H), 2.14 (d, J=18 Hz, 1 H, C8 H), 2.02 (dd, J=11 Hz, 5 Hz, 1 H, C4a H), 1.77 (s, 3H, ═C—Me), 1.21 (s, 3 H, C5-Me), 1.10 (s, 3 H, C8a-Me).
Compound 42 [from a mixture of 42 (major) and 47 (minor)]: 1 H NMR δ6.77 (m, 1 H, C3 H), 5.68 (m, 1 H, C7 H), 5.53(dd, J=10 Hz, 2 Hz, 1 H, C6 H), 3.62 (s, 3 H, OMe), 2.62 (d, J-13 Hz, 1 H, CH 2 CO 2 ), 2.38-2.26 (a series of m, 4 H), 2.12 (d, J=18 Hz, 1 H, C8 H), 2.01 (dd, J=11 Hz, 5 Hz, 1 H, C4a H), 1.77 (s, 3 H, ═C—Me), 1.12 (s, 3 H, C5-Me), 1.07 (s, 3 H, C8a-Me); 13 C NMR δ [a mixture of 42 (designated as A) and 47 (designated as B) 204.5 (s, C 1, A), 204.47 (s, C1, B), 172.5 (s, C2, A), 171.8 (s, C2, B), 143.7 (d), 134.8 (s), 133.8 (s), 133.7 (s), 133.4 (d, A), 132.5 (d, B), 123.7 (d, A), 123.5 (d, B), 51.5, 51.45, 48.0, 47.2, 46.9, 44.3, 44.1, 43.6, 41.7, 38.1, 36.7, 33.7, 33.1, 28.4, 24.3, 23.9, 23.8, 18.0, 17.99, 16.43 (q, A), 16.41 (q, B).
(4aS,8aS)-(1H)-1-Oxo-4,4a,5,8,8a-pentahydro-2,5,8a-trimethylnaphthalene-5-acetic acid (43); a mixture of 2.2:1 of 5R and 5S)
A solution of 0.127 g (0.48 mmol) of methyl esters 42 and 47 (2.2:1) and 90 mg (1.6 mmol) of KOH in 0.5 mL of water and 2 mL of MeOH was stirred at room temperature for 22 hours. The solution was acidified with 1 N aqueous HCl, extrated three times with CH 2 Cl 2 , and the combined extract was washed with brine, dried (MgSO 4 ), concentrated, and column chromatographed on silica gel using hexane:ether (1:1) as eluant to give 0.116 g (96% yield) of the acids 43 as a mixture of 2 isomers at C5.
Compounds 43: 1 H NMR δ6.79 (m, 1 H, C3 H), 5.74-5.6 (m, 1 H, C7 H), 5.57 (dd, J=10 Hz, 2 Hz, 1 H, C6 H), 2.64 (d, J=13 Hz, 1 H, CH 2 CO 2 ), 2.42-2.2 (a series of m, 4 H), 2.16 (d, J=18 Hz, 1 H, C8 H), 2.05 (dd, J=11 Hz, 5 Hz, 1 H, C4a H), 1.77 (s, 3 H, ═C—Me), 1.24 (s, 3 H, C5-Me of minor isomer), 1.15 (s, 3 H, C5-Me of major isomer), 1.11 (s, 3 H, C8a-Me of minor isomer), 1.08 (s, 3 H, C8a-Me of major isomer); 13 C NMR δ [a mixture of the α-isomer (major) (designated as A) and β-isomer (minor) (designated as B) 204.75 (s, C1, A), 204.55 (s, C1, B), 178.4 (s, C2, B), 177.5 (s, C2, A), 143.9 (d, A), 143.84 (d, B), 133.9 (B), 133.8 (A), 133.0 (A), 132.2 (B), 124.2 (A), 123.9 (B), 48.1,46.8, 44.4, 44.2, 43.6, 41.8, 38.2, 36.6, 33.8, 33.1, 28.4, 24.4, 24.0, 23.9, 18.1, 16.51 (q, A), 16.49 (q, B).
(1S,4aS,8aS)-(1H)-1-[2-(1,3-dithianyl)]-1-hydroxy-4,4a,5,8,8a-pentahydro-2,5,8a-trimethylnaphthalene-5-acetic acid (44)
To a cold (0° C.) solution of 0.116 g of 1,3-dithiane (9) in 4 mL of THF under argon was added 0.6 mL (0.97 mmol) of n-BuLi (1.6 M in hexane). After the solution was stirred at −10° C. for two hours, a solution of 0.080 g (0.32 mmol) of enone 43 in 1 mL of THF was added via cannula. The solution was stirred at room temperature for 16 hours, diluted with 20 mL of water and 5 mL of 6 N HCl, and extracted three times with 40 mL portion of methylene chloride. The combined extract was washed with 30 mL of water, and 30 mL of brined, dried (MgSO 4 ), concentrated and column chromatographed on silica gel using a gradient mixture of hexane and diethyl ether as eluant to give a good yield of 44. 1 H NMR (CDCl 3 ) δ5.75 (m, 1 H, C7 H), 5.6 (broad s, 1 H, C3 H), 5.58 (dd, J=10 Hz, 2 Hz, 1 H, C6 H), 4.57 (s, 1 H, CH—S), 2.9-2.6 (m, 4 H, CH 2 S), 2.41 (d, J=14 Hz, 1 H, CH 2 CO 2 H), 2.25 (d, J=14 Hz, 1 H, CH 2 CO 2 H), 2.3—1.2 (a series of m, 7 H), 1.83 (s, 3 H, ═CCH 3 ), 1.08 (s, 3 H, Me), 1.01 (s, 3 H, Me).
Biological Studies
Acetylcholinesterase Assay and Inhibition Kinetics: Tricyclic pyrones of this invention were tested for inhibition of AChE. The activities of electric eel acetylcholinesterase (EC 3.1.1.7, Sigma Chemical Co., St. Louis, Mo.), and fetal bovine serum acetylcholinesterase (Ralston, J. S. et al. (1985), “Acetylcholinesterase from Fetal Bovine Serum,” J. Biol. Chem. 260:4312-4318) were determined colorimetrically by the method of Ellman (Ellman, G. L. et al. (1961), “A new and rapid colorimetric determination of acetylcholinesterase activity,” Biochem. Pharmacol. 7:88-95) as described by Main et al. (Main, A. R. et al. (1974), “Purification of cholinesterase from horse serum,” Biochem. J. (1974)143:733-744). Reactions were carried out at 30° C. in 0.1 M sodium phosphate buffer at pH 8.0 in the presence of 10 −3 acetylthiocholine and 3.3×10 −4 M 3-carboxy-4-nitrophenyl disulfide. Aliquots of incubating mixtures containing enzyme alone, or enzyme in the presence of each carbamate, were withdrawn at selected time intervals and assayed for enzyme activity in order to obtain kinetic data. From the kinetic data, inhibition and bimolecular rate constants were calculated by the equation: 1 k app = 1 k 3 + K T k 3 - 1 [ I ]
in which k app is the pseudo-first-order rate constant. The bimolecular rate constant (k 3 ′) is equal to k 3 /K T . All the tricyclic pyrones are inactive against butyrylcholinesterase (BChE). BChE does not affect the formation of Aβ. The AChE inhibitory data of various tricyclic pyrones are summarized in Table 3. The inhibition of Ki of the tricyclic pyrones are in the μM range; while tacrine, an art-known AChE inhibitor, is in the nM range.
TABLE 3
The AChE inhibition constant Ki of various tricyclic pyrones
Tricyclic Pyrones
Ki(μM) ± std. error
1A
7 ± 1.2
1B
20 ± 5.8
1D
5 ± 1.7
2B
8 ± 2.3
2D
26 ± 2.3
3A
23 ± 3.5
3B
4 ± 0.6
3D
15 ± 5.8
tacrine
1 nM
Inhibition of liver and intestinal microsomal ACAT activity: Several synthesized tricyclic pyrones were tested for their inhibition of liver and intestinal microsomal ACAT along with pyripyropene A and CP-113,818 (as control) (Marzetta, C. A. et al. (1994), “Pharmacological properties of a novel ACAT inhibitor (CP-113,818) in cholesterol-fed rats, hamsters, rabbits, and monkeys,” J. Lipid Res. 35:1829-1838). Microsomes were prepared from liver and intestinal mucosal scrapings by sequential centrifugation and in vitro ACAT activity assays were done according to the method of Billheimer (Billheimer, J. T. (1985), “Cholesterol acyltransferase,” In Methods in Enzymology 111:286-293). Briefly, 100 μg microsomal protein, 22 μg BSA, and 52 nmol cholesterol and the synthesized drug in 5 μL DMSO were preincubated for 30 minutes at 37° C. in a phosphate buffer (200 μL total volume). After 30 minutes, 1 nmol [ 14 C]oleoyl-CoA was added as substrate and incubated for an additional 20 minutes. The reaction was stopped with the addition of 1 mL ethanol and lipids were extracted with hexane. Cholesteryl [ 14 C]oleate formation was quantified by thin-layer chromatography and data are expressed as percent inhibition of ACAT activity (pmol/μg protein per minute) compared to a control sample incubated with no drug. All samples were run in duplicate. Using the literature IC 50 value of pyropyropene of 58 nM as standard, it was found that IC 50 values for 2A, 3A, and 1D are 50 μM, 63 μM, and 52 μM, respectively.
TABLE 4
The Inhibition of ACAT by tricyclic pyrones and CP-113,818.
Compound
Concentration
% Inhibition
24
100
μM
3.3
50
μM
1.9
26
100
μM
13.7
50
μM
2.7
38B
100
μM
11.4
50
μM
9.7
37
100
μM
52.4
50
μM
36.8
30
100
μM
21.9
50
μM
13.3
29
100
μM
39
50
μM
21
28
100
μM
30
50
μM
17
32
100
μM
7.9
50
μM
10.3
33
100
μM
76
50
μM
57
CP-113,818
44
nM
42.5
Inhibition of DNA Synthesis: Tricyclic pyrone derivatives of this invention were tested for their ability to prevent L1210 leukemic cells from synthesizing DNA and growing in vitro. At 50 μM, a pyripyropene analog, 22, has no effect, whereas four pentahydro-3-aryl-1-oxopyrano[4,3-b][1]benzopyrans all inhibit DNA synthesis by 79-91% and tumor cell growth by 93-100%. These inhibitory effects are concentration-dependent with IC 50 around 8.5 μM for DNA synthesis at 2 h and 1.1 μM for tumor cell growth at 4 days. The aryl groups of the antitumor agents tested are either 3,4-dimethoxyphenyl or 3-pyridyl. Introduction of a methyl group at C5a and a formyloxy or hydroxy group at C6 does not alter the antitumor effects of the 3,4-dimethoxyphenyl benzopyrans but reduces those of the 3-pyridyl benzopyrans, which, at 50 μM inhibit DNA synthesis by only 32-49% and fail to alter tumor cell growth. The 4-hydroxy-6-(3-pyridyl)-2-pyrone (5B) has no effect and the tricyclic pyrones lacking aryl groups (e.g., 1A-1E) have less inhibitory effect on DNA synthesis, suggesting that a greater conjugation is required for the antitumor activity. The tricyclic pyrones also inhibit to a similar degree other macromolecule synthesis, e.g., RNA and protein synthesis. The 3,4-dimethoxyphenyl substituted tricyclic pyrone 3A being a more potent inhibitor of macromolecule synthesis than the 3-pyridyl substituted tricyclic pyrone 2A. Additionally, the tricyclic pyrones inhibit the growth of EMT6 mammary carcinoma cells and MCF-7 human breast cancer cells. However, in both these systems, tricyclic pyrone 2A has a greater inhibitory effect than tricyclic pyrone 3A. This lack of correlation between the ability of tricyclic pyrones to inhibit tumor cell growth and macromolecular synthesis suggests that other macromolecular targets may be involved in the antitumor action of these drugs.
Inhibition of Tubulin Polymerization
Tricyclic pyrone derivatives of this invention were tested for their ability to prevent tubulin polymerization. It was found that 2A completely inhibits tubulin polymerization and, therefore, works as a novel microtubule (MT) de-stabilizing drug. The ability of 2A to disrupt MT dynamics suggests that the anticancer activity of tricyclic pyrones may be cell cycle-specific. These anticancer drugs are therefore useful for arresting mammalian cells in mitosis. Tricyclic pyrones that can selectively disrupt MT dynamics and block the M-phase of the cell cycle have great therapeutic value.
Tubulin is a labile protein, which is unstable below 80 mM PIPES, should not be exposed to pH values less than 6.8 or greater than 7.0, and will not polymerize in the presence of Ca 2+ . GTP and Mg 2+ are necessary for tubulin nativity and glycerol stabilizes tubulin and lowers the initial concentration required to initiate polymerization.
The ability of 2A to alter the polymerization of pure tubulin in a cell-free system in vitro was analyzed using the assay kit purchased from Cytoskeleton (Denver, Colo.). The polymerization reaction contained, in a final volume of 200 μl, tubulin protein from bovine brain (2.5 mg/ml), 80 mM PIPES buffer, pH 6.8, 1 mM MgCl 2 , 1 mM EGTA, 1 mM GTP and 10% glycerol. Compound 2A was added in 2 μl of DMSO:tubulin buffer (40:60) to obtain a final concentration of 25 μM. This vehicle did not affect the rate of tubulin polymerization in drug-untreated control reactions. Samples were incubated at 35° C. in quartz microcells and the rate of tubulin polymerization was followed over 20 min by measuring the increased absorbance of the solution at OD 340nm , using a Shimadzu UV-160 spectrophotometer equipped with dual-beam optics and a thermostatically-controlled cell holder.
FIGS. 14A-B show the three typical phases of MT polymerization normally occurring in vehicle-treated control samples. The lag phase I is necessary to create nucleation sites (small tubulin oligomers) from which longer MT polymers can form. The growth phase II reflects the rapid increase in the ratio of MT assembly: disassembly occurring under those experimental conditions. And the steady phase III is established when the residual concentration of free tubulin heterodimer becomes equal to the critical concentration required to initiate polymerization. One unit of tubulin is defined as 5 mg of purified protein. When tubulin at a concentration of 1 unit (5 mg)/ml is incubated at 35° C. for 30 min. in the presence of 80 mM PIPES, pH 6.8, 1 mM MgCl 2 , 1 mM EGTA, 1 mM GTP and 10% glycerol, the OD 340nm increases from 0.0 to 1.0, which indicates that about 97% of tubulin has polymerized to form a total MT polymer mass of 4.8 mg/ml. An increase in OD of 0.2 is roughly equal to a MT polymer mass of 1 mg/ml. The kinetics of MT polymerization in FIG. 14A, therefore, appear consistent with the initial concentration of 2.5 mg tubulin/ml used in our control assay. In contrast, no significant MT polymerization can be detected in the presence of 25 μM of 2A in FIG. 14 B.
Materials and Methods
All solutions of tricyclic pyrone analogs were dissolved and diluted in 100% ethanol (ETOH), whereas CPT (Sigma Chemical Co., St. Louis, Mo.) solutions were prepared in 100% dimethyl sulfoxide (DMSO). Murine L1210 lymphoblastic leukemia cells, obtained from the American Type Culture Collection (Rockville, Md.), were maintained in continuous exponential growth by twice-a-week passage in RPMI 1640 medium supplemented with 7.5% fortified bovine calf serum (HyClone Laboratories, Inc., Logan, Utah). The cultures were incubated at 37° C. in a humidified atmosphere containing 5% CO 2 . All drugs were supplemented to the culture medium in 1- or 2 μl aliquots. The concentration of vehicle in the final incubation volume never exceeded 0.2-0.4%. Such low concentrations of EtOH or DMSO do not affect the rates of DNA synthesis and growth in L1210 cells. Control cells incubated in the absence of drugs were similarly treated with vehicle only and, in every experiment, all incubates received the same volume of solvent.
For DNA synthesis, L1210 cells were resuspended in fresh serum-free RPMI 1640 medium at a density of about 2.5×10 6 cells/0.5 ml. The cells were incubated at 37° C. for 90 min in the presence or absence of drugs and then pulse-labeled for an additional 30 min with 1 μCi of [methyl- 3 H]thymidine (51 Ci/mmol; Amersham Corp., Arlington Heights, Ill.). The incubations were terminated by the addition of 0.5 ml of 10% trichloroacetic acid (TCA). After holding on ice for 15 min, the acid-insoluble material was recovered over Whatman GF/A glass microfibre filters and washed thrice with 2 ml of 5% TCA and twice with 2 ml of 100% EtOH. After drying the filters, the radioactivity bound to the acid-precipitable material was determined by liquid scintillation counting in 10 ml of Bio-Safe NA (Research Products International Corp., Mount Prospect, Ill.).
For tumor cell growth, L1210 cells were resuspended in fresh serum-containing RPMI 1640 medium, plated at an initial density of 1×10 4 cells/0.5 ml, and incubated in 48-well Costar cell culture plates (Costar, Cambridge, Mass.). Cells were grown for 4 days in the presence or absence of drugs and their density was monitored every 24 h using a Coulter counter (Coulter Electronics, Ltd., Luton Beds, England). Data of all in vitro experiments were analyzed using Student's t-test with the level of significance set at P<0.05.
The known anticancer drug CPT inhibits the incorporation of 1 H-thymidine into DNA in a concentration-dependent manner (FIG. 1 ). When tested at 25 μM, the new agent 3A inhibits DNA synthesis in L1210 cells by 62% but 22, 2D & 2E and 5B have no significant effects (FIG. 1 ). However, 2D & 2E can inhibit DNA synthesis by 49% at 50 μtM (FIG. 2 ). In contrast, 22 and 5B remain ineffective even at this higher concentration (FIG. 2 ). Overall, four of the newly synthesized compounds can prevent leukemic cells from synthesizing DNA. Indeed, 50 μM 3A, 3D & 3E, 2A and 3B & 3C inhibit DNA synthesis in L1210 cells by 79-91%, an effect comparable to that of 20 μM CPT (FIG. 2 ). Besides 2D & 2E, which is a moderate inhibitor, the three remaining new compounds tested have very weak inhibitory effects on DNA synthesis in L1210 cells. At 50 μM, 2B & 2C, 1A, and 1D & 1E inhibit this DNA response by only 17-32% (FIG. 2 ).
Although less potent than CPT, 3A and 2A both inhibit the DNA response of L1210 cells in the same concentration-dependent manner (FIGS. 3 and 4 ). In this L1210 system in vitro, the concentration of 3A or 2A that inhibits DNA synthesis by 50% (IC 50 ) is about 8.5 μM, whereas that of CPT is about 0.65 μM (FIGS. 3 and 4 ).
The ability of several of the new tricyclic pyrone analogs to inhibit the growth of L1210 cells in culture was assessed and compared to that of CPT (FIGS. 5 and 6 ). Over a 4-day period, there is a 50-fold increase in the number of control cells grown in the absence of drugs (FIG. 5 ). Since 22 and 5B fail to inhibit DNA synthesis (FIG. 2 ), their ability to alter L1210 cell growth has not been tested. It should be noted that 50 μM 2D and 2E and 2B and 2C, which inhibit the DNA response of L1210 cells by 31-49% (FIG. 2 ), cannot inhibit the growth of these leukemic cells over a 4-day period (FIG. 5 ). The effects of 1A and 1D and 1E on L1210 cell growth, therefore, are not worth testing. Since these compounds inhibit DNA synthesis to a lesser degree than 2D and 2E and 2B and 2C (FIG. 2 ), they are very unlikely to significantly decrease tumor cell growth in vitro. In contrast, the same four new compounds shown to inhibit DNA synthesis by 79% or more (FIG. 2) also dramatically block the growth of L1210 cells in vitro (FIG. 5 ). At 50 μM, 3A, 3D and 3E, 2A and 3B and 3C all mimic the inhibition of L1210 cell growth caused by 10 μM CPT (FIG. 5 ). The similar magnitude of these inhibitory effects is more evident on a non-logarithmic scale. Indeed, 50 μM 3A, 3D and 3E, 2A and 3B and 3C all reduce the increasing numbers of untreated L1210 cells observed in control wells after 3 and 4 days in culture by 91-100% (FIG. 6 ).
The ability of 3A and 3D and 3E to inhibit the growth of L1210 cells in vitro is clearly concentration-dependent between 3.12 and 50 μM (FIGS. 7 - 9 ). On an equal concentration basis, 3D and 3E are slightly more effective than 3A but 50 μM concentrations of these new agents are required to match the inhibitory effect of 3.12 μM CPT. When the inhibitory effects are expressed as % of the increasing numbers of untreated cells present each day in control culture wells, the magnitudes of inhibition for each concentration of 3A and 3D and 3E generally increase over a 4-day period (FIGS. 8 and 9 ). Because the drugs increasingly slow down or block the rate of tumor cell growth, the difference between the number of exponentially growing a control cells and the reduced number of drug-treated cells keeps increasing with the number of days in culture. This effect is even more apparent with 2A (FIGS. 10 and 11 ).
The inhibition of tumor cell growth by 2A increases with the concentration tested (FIG. 10 ). And the effectiveness of each concentration increases with the time in culture (FIG. 11 ). But the shape of the concentration-response curve is similar at each time point tested. For instance, every day, the concentration-dependent inhibitory effect of 2A is maximal at 6.25 μM and plateaus thereafter (FIG. 11 ). However, the 6.25 μM concentration of 2A reduces the increasing numbers of untreated L1210 cells observed at 1, 2, 3 and 4 days in control wells by 28, 74, 90 and 94%, respectively (FIG. 11 ). These results, therefore, suggest that the effectiveness of 3A, 3D and 3E, 2A and 3B and 3C as inhibitors of tumor cell growth in vitro is a combination of drug concentration and duration of action. Obviously, concentrations of 2A much smaller than 1.56 μM should be tested since this level of drug has no effect after 24 h but inhibits tumor cell growth by 83% after96 h (FIG. 11 ).
Concentrations of 2A up to 8 times lower than 1.56 μM, therefore, were tested in another experiment for their ability to inhibit the growth of L1210 cells in vitro (FIGS. 12 and 13 ). Again, the concentration-dependent inhibitory effects of 2A (FIG. 12) clearly increase with the number of days in culture (FIG. 13 ). As a result, the concentrations of 2A that reduce by 50% (IC 50 ) the increasing numbers of untreated cells in control wells at 1, 2, 3 and 4 days are 11.0, 2.0, 1.1 and 1.1 μM, respectively (FIG. 13 ). Similarly, 0.78 μM CPT reduces the increasing numbers of untreated L1210 cells observed at 1, 2, 3 and 4 days in control wells by 46, 85, 97 and 99%, respectively (FIG. 13 ). The magnitude of this effect over a 4-day period is mimicked by 6.25 μM 2A, suggesting that this new tricyclic pyrone analog is about 8 times less potent than the anticancer drug CPT at inhibiting leukemic cell growth in vitro, an observation which is consistent with the respective potencies of 2A and CPT on DNA synthesis in the same L1210 system. The apparent discrepancy between the effects of 1.56 μM 2A on DNA synthesis (FIG. 4) and tumor cell growth (FIGS. 11 and 13) may simply be due to the fact that the incorporation of 3 H-thymidine into DNA was determined after only 90 min of drug treatment. Longer periods of incubation prior to pulse labelling might be required to demonstrate the inhibitory effects of low concentrations of 3A, 3D & 3E, 2A and 3B & 3C on DNA synthesis.
This invention is described with reference to preferred embodiments; however, it will be apparent to those skilled in the art that additional equivalent procedures and compositions may be substituted in the practice of this invention for those disclosed herein within the scope and spirit of applicants' contribution to the art. The appended claims are to be interpreted to include all such modifications and equivalents. | This invention provides cancer-active tricyclic and tetracyclic oxypyrones and a method of synthesizing these compounds. Preferred compounds have aryl groups at the 3-position of the oxypyrone ring. The tricyclic oxypyrone synthetic method is a simple condensation reaction of pyrones with cyclohexenecarboxaldehydes, providing high yields and using few steps. The tetracyclic oxypyrone synthetic method is a simple condensation reaction of carvones with pyrones. | 2 |
BACKGROUND OF THE INVENTION
A system is disclosed in the U.S. patent application Ser. No. 431,649 filed on Jan. 8, 1974 wherein logic means are used to select and release stitch information stored in memory means in timed relation with the operation of a sewing machine. Digital information from the memory means is converted to positional analog signals which control closed loop servo means including moving coil linear actuators directly controlling the position of conventional stitch forming instrumentalities of a sewing machine in the formation of ornamental patterns.
In this prior art system no means was disclosed for adjusting the feed pattern for ornamental variation. In addition, in this prior art system, feed balance, for instance in a buttonhole, to have the appearance of one leg of a buttonhole generated during forward feed conform to the appearance of the other leg of the buttonhole generated during reverse feed, was achieved by a variable balance control voltage which decreased forward feed when increasing reverse feed and vice versa. Thus with the prior art system any adjustment of feed balance would affect the density of both legs of a buttonhole simultaneously but would not necessarily be optimized insofar as the desired stitch density for each leg of the buttonhole was concerned.
In this prior art system, bight adjustment was achieved by a scaling resistor which was found to have an adverse loading effect on the circuit, changing circuit parameters which influenced linearity.
What is required is a means of providing for feed pattern variation, a means to individually control forward and reverse feed to obtain for example an optimum buttonhole that would have a balanced appearance, and a means for obtaining bight adjustment which would not suffer from the above noted drawbacks.
SUMMARY OF THE INVENTION
In the present invention an operational amplifier, interposed between a digital-to-analog converter and the servo amplifier system for both feed and bight pattern information, utilizes a feedback loop including a rheostat, variable to control the gain of the buffer amplifier and thereby the analog input signal to the servo amplifier system.
A commercially available FET switch is biased and latched in the conductive state by logic means, on operator command, thereby to insert the wiper of the rheostat into the circuit of the feedback loop for adjustment of feed or bight during ornamental pattern stitching.
A similar FET switch may be placed in the conductive state as signalled by the logic means only during reverse feed. To accomplish the aforesaid, the logic means may sense some characteristic of reverse feed, or of forward feed which indicates an absence of reverse feed. Thus a balance control voltage from a potentiometer connected as a voltage divider to a double ended reference voltage of a power supply may be introduced at a summing point of the servo amplifier system to obtain separate control over reverse feed in order to achieve an optimum buttonhole or optimum aesthetic effect in ornamental stitching.
DESCRIPTION OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. The invention itself, however, both as to its organization and method of operation thereof may be best understood by reference to the following description taken in connection with the accompanying drawings, in which:
FIG. 1 is a perspective view of a sewing machine including fragments of a typical driving mechanism and of a needle jogging and work feeding mechanism and illustrating the physical elements necessary to an embodiment of this invention applied thereto;
FIG. 2 is a general schematic block diagram of the feed portion of a system according to the present invention;
FIG. 3 is a schematic block diagram of a portion of the LSI indicating a method for sensing reverse feed;
FIG. 4 is a code table for the feed indicating the code words for the various feed positions;
FIG. 5 is a detailed circuit diagram of the servo amplifiers, feedback loops and balance control according to this invention; and,
FIG. 6 is a schematic block diagram of a preferred override latch arrangement for inserting the variable feedback loops shown in the circuit diagram, FIG. 5.
DESCRIPTION OF THE INVENTION
Referring to FIG. 1 there is shown in phantom a sewing machine casing 10 including a bed 11 and a bracket arm 12 supported in overhanging relation to the bed by a standard 13. The bracket arm 12 terminates in a head portion 15, within which is supported in a conventional manner a needle bar gate 17 which supports for endwise reciprocation therein a needle bar 16. The needle bar 16 is caused to undergo endwise reciprocation by an armshaft 20 by any conventional connection (not shown). The needle bar 16 carries in its extremity a needle 18 which cooperates with stitching instrumentalities (not shown) in bed 11 in the formation of sewing stitches.
The needle bar gate 17 is urged to impart lateral jogging motion to the needle bar 16 by a driving arm 21 pivoted to the needle bar gate as at 22. The driving arm 21 is connected to a reversible linear actuator 25 fully described and explained in the U.S. patent application Ser. No. 431,649, filed on Jan. 8, 1974, and assigned to the same assignee as the present invention, which is incorporated by reference herein. The linear actuator 25 is therefore used to determine lateral position of the sewing needle 18.
Also illustrated in FIG. 1 is a fragment of a work feed mechanism including a feed dog 26 carried by a feed bar 27. The mechanism illustrated for imparting work transporting movement to the feed dog includes a feed drive shaft 28 driven by gears 29 from a bed shaft 19, which is interconnected with the armshaft 20 in timed relationship by a conventional mechanism (not shown). A cam 30 embraced by pitman 31 is connected to a slide block 32, by pin 33, to reciprocate the slide block in a slotted feed regulating guideway 34. The pin 33 is also pivotably connected to horizontal line 35 which is itself pivotably connected to the feed bar 27. Thus for a given inclination of the guideway 34, a predictable horizontal motion of the slide block ensues and is transferred to the feed dog 26 by the horizontal link 35 and feed bar 27.
The inclination of the feed regulating guideway 34 may be adjusted by rotation of shaft 36 affixed to the guideway. The shaft 36 has a rock arm 37 affixed to the opposite extremity thereof which is connected by a rod 38 to a second reversible linear actuator 40 supported by support bracket 41 suitably attached to the sewing machine casing 10 by screws 42, only one of which is visible. Thus the linear actuator 40 is utilized to determine the feed rate of the sewing machine.
Referring to FIG. 2 there is depicted a general schematic block diagram for the feed controlling portion of the sewing machine only. The block diagram for bight control would be substantially similar except for differences to be further discussed below when referring to FIG. 5, the detailed circuit diagram of the servo amplifiers. The pattern information required to drive the linear actuators 25 and 40 originates preferably in a MOSFET Large Scale Integration (LSI) integrated circuit 50 (See also FIG. 1). A method by which the proper pattern information may be extracted from the LSI 50 to be presented to the respective digital to analog converters for bight and feed is disclosed in the U.S. Pat. No. 3,855,956, assigned to the same assignee as the present invention, which is hereby incorporated by reference herein. In that patent, a system is disclosed wherein digital information related to the positional coordinates for each stitch of a predetermined stitch pattern is stored in a static memory, such as the LSI 50. A pulse generator 45 (see also FIG. 1) driven in timed relation with the sewing machine produces a timing signal pulse between each successive stitch. These signal pulses are counted up in a counter to provide a time series of progressively increasing binary numbers corresponding to the progressively increasing number of stitches in the pattern. The counter output is applied as the address to the memory to recover as output therefrom the digital information related to the positional coordinates for each stitch of the predetermined pattern. The memory output is applied to control driving devices operatively connected to impart a controlled range of movement to the needle and the feed of the sewing machine to produce a specific predetermined position coordinate for the needle penetration during each stitch formation.
Thus in FIG. 2, the pulses from the pulse generator 45 are counted up in Binary Counter 46 and presented as address inputs to the LIS 50. The LSI 50, as shown in FIG. 1 is mounted on logic printed circuit board 49. The LSI 50 presents as output digital information related to the positional coordinates for each stitch in pulse width modulated form to digital-to-analog converters 52 for feed, and bight (not shown in FIG. 2). The LSI 50 may include a latch whereby the bight information may be held for later release to the bight servo system at a time appropriate to the operation of the needle jogging mechanism. Similarly the feed information may also be retained by a latch in the LSI 50 for later release to the feed servo system at a time appropriate to the operation of the feed regulating guideway 34. Proper timing for release of the bight or feed information may be determined by the pulse generator 45. Since the systems for the bight and for the feed are identical except for the specific switching necessary for balance control in the feed regulating system, the following description will for convenience, be confined to the feed system only and the specific switching for the balance control will be described later. Corresponding components in each system carry the same reference number except that the numbers associated with the bight or needle jogging system are primed.
The pulse width modulated signal presented along line 51 to the digital-to-analog converter 52 is filtered, offset by voltage divider 101 and scaled by rheostat 102 in the converter in order to accommodate a specific LSI 50 to those components between the LSI and the load, to account for manufacturing variability (See also FIG. 5). The analog signal from the D/A converter 52 outputs on line 53 to a feed signal control amplifier 54, which outputs on line 55 to the summing point 56 of a low level preamplifier 65 of a servo amplifier system described in the aforereferenced patent application Ser. No. 431,649. Further description of the servo amplifier system will be given below.
The output from the feed signal control amplifier 54 is also transferred via line 57 to FET 60a of the enhancement type, having its gate connected by gate line 58 to the LSI 50. On suitable command the LSI 50 will apply a gate voltage through a latch circuit to FET 60a by way of gate line 58 thereby to place and retain FET 60a in the conductive or ON condition. A feedback signal then passes through line 57 and FET 60a to a wiper of a rheostat, constituting manual stitch length control block 59.
Thus the gain of the feed signal control amplifier 54 may be controlled during pattern stitching or straight stitching. Referring to FIG. 1, the manual stitch length control rheostat 62, adjusted by knob 61, is mounted on power supply and override printed circuit board 63. Command to the LSI 50 to apply a gate voltage to FET 60a may be accomplished by a proximity switch, associated with knob 61, of the type described in the U.S. patent application Ser. No. 596,685 filed on July 16, 1975, entitled "Digital Differential Capacitance Proximity Switch." Rotation of knob 61 rotates wiper 59 of rheostat 62 for adjustment of feedback signal.
Referring to FIG. 6 there is shown a schematic block diagram of an override latch arrangement which may be implemented to retain, on operator command, the FET 60a in the ON condition for manual control of the feed signal. When the knob 61 (see FIG. 1) is touched by an operator, a proximity detector 105, of the type disclosed in the above referenced application, becomes active and presents an input signal to AND gate 106 and mismatch AND gate 108. If the feed override latch 107 is not set, that is the output Q' is a logical 1, the mismatch AND gate 108 outputs a signal to an input noise filter logic 110 on mismatch line 111. If the signal remains on line 111 for a period of from 80-160 micro seconds, the filter logic 110 presents a pulse signal on gate line 112 to the second input of AND gate 106, thereby setting the latch 107 to output a logical 0 at Q'. The mismatch AND gate 108, having a logical 0 as an input ceases to output a signal to the filter logic 110. A LED driver 115, implemented by an inverter, inverts the logical 0 input to provide a control signal to FET 60a by way of gate line 58 and to indicating LED's 116 mounted on a control panel (See FIG. 1).
The input noise filter logic 110 may also receive a signal from pattern selection buttons 120, also located on a control panel, which, if maintained for 80-160 micro sections, causes the filter logic to send a reset pulse along reset line 113 to reset the latch 107. The latch 107 outputs on Q' a logical 1, until again set by a signal from proximity detector 105 as explained above.
A similar arrangement may be implemented for bight control, initiated by contact with knob 61' (See FIG. 1). All of the components shown in FIG. 6, and the similar components required for bight control, may be implemented as part of LSI 50.
In the detailed circuit diagram of FIG. 5 the feed signal control amplifier 54 is indicated as an operational amplifier with rheostat 62 providing the feedback to the input. A MOSFET module 60, such as RCA type CD4016A, comprises four independent bilateral signal switches, one of which is 60a. The module may also be mounted on P.C. board 63 (see FIG. 1). As schematically indicated in FIG. 5 a voltage signal from LSI 50 on line 58 will place FET 60a in an ON condition, inserting the wiper 59, of rheostat 62 in bypass arrangement in the feedback circuit. Thereby feedback resistance of the operational amplifier 54 may be reduced to decrease to gain of the operational amplifier and reduce the analog signal to the summing point 56 of the low level preamplifier 65 of the servo amplifier systems mounted on servo circuit board 64 (see FIG. 1). The preamplifier 65 drives a power amplifier 66 which supplies direct current of reversible polarity to the electromechanical actuator 67, which in the broadest sense comprises a reversible motor, to position the actuator in accordance with the input analog voltage on line 55. A feedback position sensor 68 (see also FIG. 1) mechanically connected to the reversible motor 67 provides a feedback position signal on line 69 indicative of the existing output position. The input analog voltage and the feedback signal are algebraically summed at the summing point 56 to supply an error signal on line 70. The feedback signal from the position sensor is also differentiated with respect to time in a differentiator 71 and the resulting rate signal is presented on line 72 to the summing point 73 of the power amplifier 66 to modify the positional signal at that point. The position sensor 68 may be any device that generates an analog voltage proportional to position and may, in this embodiment, be a simple linear potentiometer connected to a stable reference voltage 74 (see FIG. 5) and functioning as a voltage divider. The differentiator 71 is preferably an operational amplifier connected to produce an output signal equal to the time rate of change of the input voltage as is well known in this art.
While the reversible motor 67 may be a conventional low-inertia rotary d.c. motor, it is preferable, for the purposes of the present invention that it takes the form of a linear actuator in which a lightweight coil moves linearly in a constant flux field and is directly coupled to the load to be positioned. This simplifies the driving mechanical linkage and minimizes the load inertia of the system.
Thus far it has been shown that the input to the feed (or bight) servo amplifier system may be attenuated to obtain a smaller pattern than is stored in the LSI 50, or for control of stitch length in straight stitch. However further control is required in the feed system to compensate for work related discrepancies such as the type and thickness of material being stitched, the pressure being applied by the presser foot and the rate of feed. Problems are usually encountered in closed pattern sewing, particularly in buttonhole stitching where the appearance of both legs of the buttonhole are ideally, identical, or balanced. Ornamental pattern stitching where the sewing needle is required to pass through a point in the work material more than once also presents a problem.
In the prior art sewing machines these work related discrepancies were accommodated by mechanically or electronically shifting the feed signal, however derived, in a fashion that altered forward feed while correcting reverse feed or vice versa. A system will now be described in which individual control over forward feed and reverse feed may be obtained in order to readily achieve an optimum balanced buttonhole or ornamental pattern, which also lends itself to ornamental variation not normally obtainable.
Referring to FIGS. 2 and 5, a manual balance control potentiometer 75 is connected as a voltage divider to the double ended reference voltage output of voltage regulator 74 in the power supply. The wiper of the balance control potentiometer 75 is connected by line 77 to FET 60b, which is connected by line 78 to the summing point 56. The gate of FET 60b is connected to LSI 50 by gate line 79. The LSI 50 applys a voltage to the gate line 79 to place the FET 60b in the ON condition only during reverse feed. Thus a balance control voltage, obtained by adjustment of knob 80 (see FIG. 1) attached to the wiper of balance control potentiometer 75 mounted on P.C. board 63, is introduced at summing point 56 only during reverse feed, thereby varying input voltage to the feed servo amplifier system only during reverse feed. During forward feed the FET 60b is in the OFF condition and the input to the feed servo amplifier system is responsive only to the output of the feed signal control amplifier 54 as adjusted by the knob 61 of the stitch length control rheostat 62.
A preferred method by which the LSI 50 will apply a control voltage to FET 60b only during reverse feed may be understood by reference to FIG. 3, which indicated in schematic block form a portion of LSI 50, and to FIG. 4, which sets out the binary code words for all the feed increments of which the sewing machine is capable. The feed code of FIG. 4 are stored in Read Only Memory (ROM) 85 in a predetermined sequence which in conjunction with bight code words similarly stored in a predetermined sequence, may be extracted by the pulse generator 45 and binary counter 46 seriatim, as explained above and in the reference U.S. Pat. No. 3,855,956, whereby the sewing machine 10 may generate an ornamental pattern.
As indicated in FIG. 3 the feed code word extracted from the ROM 86 is transferred to and retained in a storage register 87. Inspection of the Feed Logic Code table of FIG. 4 will disclose that for all reverse feed the most significant bit (MSB) 85 retained in the storage register 87 is a binary 1 or high voltage state. The remaining code words are retained in the storage register 87 on lines 81-84 including the least significant bit (LSB) 81. Thus in the preferred embodiment the MSB 85 may be directly connected via gate line 79 to the FET 60b, thereby to place the FET 60b in the ON condition during reverse feeding for the purpose of applying an adjustable balance voltage from balance control potentiometer 75 to the summing point 56.
The code word for a particular stitch retained in the storage register 87 is transferred via lines 81-85 to a comparator 88. A binary counter 89, running continuously, counts from 0 to 31 and reverts to zero. On the count of 31 a signal is transferred from the counter 89 to flip-flop 90 via line 91, turning on the flip-flop to introduce a voltage on line 51 to the digital-to-analog converter 52. A clock 92 issues counting commands to the binary counter 89 at approximately a 100 kilohertz rate. When a 5 bit code match is attained between the code word retained by the storage register 87 and presented to the comparator 88 and the count of the binary counter 89, the comparator sends a signal along line 94 to the flip-flop 90, turning off the flip-flop and, thereby, reducing the voltage signal on line 51 to zero. Thus, the digital signal is converted from parallel form to pulse width modulated serial form. The 100 kilohertz pulse rate of the clock 92 combined with the 32 bit counting capacity of counter 89 results in a pulse width modulated signal of approximately 3 kilohertz frequency on line 51 to the digital-to-analog converter 52.
While a preferred manner of sensing a reverse feed signal has been described, other methods also suggest themselves. Thus, logic circuits may be devised and implemented which are responsive to an absence of forward feed or zero feed which are characterized by a binary 0 or low voltage in the MSB 85. Also, logic circuits may be devised and implemented which are responsive to specific code words for reverse feed.
Referring to FIG. 5, a power supply circuit 100 is indicated which may be connected to the AC house mains via a transformer (not shown) supplying 12 volt 60 hertz to the power supply. The 12 volt AC supply undergoes full wave rectification and filtration to provide ± 15VDC to the power amplifiers and also to provide, through voltage regulator 74, ± 7.5 VDC to the bight and feed position potentiometers 68' and 68 respectively and to manual balance control potentiometer 75, as well as ± 7.5 VDC to the digital-to-analog offset voltage dividers 101 and 101' in the digital-to-analog converters 52 and 52' for feed and bight respectively (see also FIG. 1). Though not shown, the power supply 100 also provides ± 7.5 volts DC to LSI 50.
As previously stated all the bight components finding a counterparts in the feed system take the same number as the feed component except that the numbers are primed. Thus the two systems, as disclosed, differ only in the incorporation of a manual balance control potentiometer 75 which by way of line 77 and FET 60b conductive only during reverse feed as previously explained, applys an adjustable voltage signal to summing point 56 for control of voltage signal to the feed servo amplifier during reverse feed only. | An improvement in a logic controlled sewing machine which permits an operator to vary by electronic means ornamental pattern bight and feed, manual stitch control, or individually control forward and reverse feed to achieve, for example, an optimum balanced buttonhole or ornamental variations to patterns. Operator influenced means are effective to signal the logic to apply a holding signal to FET switches, maintaining the FET switch in the conductive state. Closing of the FET switch inserts the wiper of a rheostat in bypass arrangement in the feedback circuit of an operational amplifier between a digital-to-analog converter for feed or bight and, respectively, a feed or bight servo amplifier system. By changing the magnitude of the resistance in the feedback circuit of the operational amplifier, the gain may be altered, thereby to control the signal to the feed or bight linear actuator for variation of stitch length or pattern width, respectively. An additional FET switch is maintained in the conductive state by the logic means only during reverse feed thereby applying a variable voltage to a summing point prior to the servo amplifier for exclusive control of reverse stitch length during pattern stitching. | 3 |
BACKGROUND OF THE INVENTION
The continuing increases in the functional capacity of integrated circuits (ICs) over the last few years have been both astounding and beneficial. However, accompanying these increases are attendant technical problems that demand creative solutions. One such problem has been the increase in input/output (I/O) pads that typically result from increases in the amount of circuitry that can be incorporated onto an IC. The number of I/O pads on a traditional wire-bonded IC, which involves bonding wires from the I/O pads of the IC die to the substrate, is generally limited by the length of the IC perimeter because such I/O pads typically reside at the edges of the IC. Thus, reductions in the size of transistors and other electronic devices incorporated on a single die generally create a need for more I/O pads than what traditional wire-bonding technology can offer.
To satisfy this need, alternatives to wire-bonding techniques have been devised to increase the overall interconnection density of ICs. One such alternative is the “flip chip,” which utilizes I/O connections across the top surface of the die. Thus, the connections are not restricted to the perimeter of the IC. Typically, solder “bumps” are formed on these connections. The solder bumps are then covered with solder flux, the die is flipped over so that the bumps make contact with the connection points of the IC substrate, and the die-substrate assembly is heated to reflow the solder. Hence, the necessary electrical contacts between the die and substrate are made by way of the solder bumps with the aid of the solder flux. FIG. 1 is a simplified perspective view of a typical flip chip assembly 100 , with a die 110 connected to a substrate 120 by way of solder bumps 130 , with die 110 and substrate 120 defining a narrow, substantially planar space 140 therebetween.
Tests on flip chip devices have shown that repeated heating and cooling of the IC during normal use tends to place sufficient thermal stress on the integrated circuit (die-substrate) assembly to cause some of the connections made via solder bumps 130 to break, creating electrical discontinuities between die 110 and substrate 120 . To prevent such breaks, an underfill material (generally an adhesive) is normally employed to fill planar space 140 to maintain the structural integrity of the assembly and prevent the electrical connections from breaking. However, after the solder reflow, some flux residue remains in planar space 140 that must be removed by way of an IC cleaning solution before the underfill can be applied. The cleaning process is vital since leftover residue within planar space 140 prevents the underfill from reaching the entirety of planar space 140 , thus adversely affecting the structural integrity and overall reliability of flip chip assembly 100 .
Complete cleaning of the flux residue from planar space 140 of flip chip assembly 100 has proven to be rather difficult. The distance between die 110 and substrate 120 is normally quite narrow, on the order of 70 um or less. Further complicating the process is the fact that several rows of solder bumps 130 may exist in planar space 140 , thus making access to all of planar space 140 even more problematic.
Currently, IC assemblies are normally cleaned using commercially available centrifugal cleaners and cleaning solutions. As shown in a simplified manner in FIG. 2, a centrifugal cleaner 200 employs a tank 210 that is filled with an IC cleaning solution 220 during the cleaning process. Centrifugal cleaner 200 usually holds several IC assemblies, such as flip chip assembly 100 , using a cleaning fixture 230 immersed in cleaning solution 220 inside tank 210 . A tank-filling mechanism (not shown) of centrifugal cleaner 200 is used to fill tank 210 with IC cleaning solution 220 . Cleaning fixture 230 is then spun or agitated on a central vertical axis in cleaning solution 220 by way of a motor 240 . Cleaning solution 220 is then drained from tank 210 , and water rinse and spin-drying cycles in centrifugal cleaner 200 then normally follow. Cleaning fixture 230 holds several flip chip assemblies 100 , or other similar IC assemblies, horizontally within IC cleaning solution 220 .
Cleaning fixture 230 may be implemented in a variety of ways. For example, cleaning fixture 230 may consist of a central carousel to which one or more cassettes are attached. Each carousel would then be loaded manually with flip chip assemblies 100 prior to the cleaning process. Also, flip chip assemblies 100 may be held in boats 300 (FIG. 3 ), each of which holds several flip chip assemblies 100 throughout a majority of the IC manufacturing process. In that case, a cleaning fixture holds several such boats 300 containing flip chip assemblies 100 to be cleaned. Other methods of implementing cleaning fixture 230 not disclosed herein are also employed in the industry.
Unfortunately, as displayed in FIG. 4, which shows a top view of flip chip assembly 100 after being agitated or spun in a bath of cleaning solution 220 in centrifugal cleaner 200 , tests have shown that cleaning solution 220 almost always fails to penetrate the entirety of planar space 140 (not shown explicitly in FIG. 4) between die 110 and substrate 120 , leaving some flux residue behind because an air pocket 400 becomes trapped in planar space 140 . When flip chip assembly 100 is positioned horizontally, cleaning solution 220 encroaches from all sides of planar space 140 simultaneously, trapping air pocket 400 approximately in the center of planar space 140 . Air pocket 400 then acts as a countervailing force against the entry of cleaning solution 220 into planar space 140 . Cleaning solution 220 is thus prevented from reaching all of planar space 140 , allowing some of the flux residue from the solder reflow phase to remain. The remaining flux residue thus prohibits the underfill material subsequently applied from occupying all of planar space 140 . Tests also confirm that no amount of spinning or agitation in cleaning solution 220 will force air pocket 400 from planar space 140 so that cleaning solution 220 may occupy all of planar space 140 .
To remedy this problem, the use of a apparatus and method of cleaning the tight spaces in integrated circuit assemblies, such as, for example, between the die and substrate of a flip-chip IC, that would result in the complete removal of the flux residue in the space would be advantageous. Without any flux residue present in the planar space, the underfill material to be applied for purposes of structural integrity may fill all of the space, thus preventing the breakage of the various connections between the substrate and die. The cleaning of other types of integrated circuit assemblies involving similar tight spaces, such as, for example, ball grid arrays (BGAs) and direct chip attach (DCA) assemblies, whereby a die is attached directly to a printed circuit board (PCB), would also benefit from such an apparatus and method.
SUMMARY OF THE INVENTION
Specific embodiments according to the present invention, to be described herein, provide an effective way of cleaning a space within an integrated circuit assembly without trapping air inside the space. For example, one embodiment of the invention provides a method of cleaning an IC assembly, such as a flip chip IC. To allow the cleaning solution to enter the space without trapping an air pocket inside, the IC assembly is held at an incline from horizontal. The IC assembly is then immersed slowly in the cleaning solution so that the space is completely filled with the cleaning solution prior to the integrated circuit assembly becoming completely submerged within the solution. Since the cleaning solution fills all of the space, all flux residue will be dissolved, allowing the underfill material used later in the IC manufacturing process to fill the entire space, helping to create a structurally reliable IC assembly.
Another embodiment of the invention involves an IC cleaning apparatus that holds an IC assembly at an incline from horizontal. The IC assembly is usually retained either directly or indirectly by a cleaning fixture. The cleaning apparatus then slowly immerses the IC assembly in the cleaning solution bath so that the cleaning solution completely fills the space, thereby allowing air in the space to escape prior to total submergence of the IC assembly in the solution.
Other aspects and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified perspective view of a typical flip chip IC assembly according to the prior art.
FIG. 2 is a simplified cross-sectional side view of an IC centrifugal cleaner according to the prior art.
FIG. 3 is a simplified perspective view of a boat that holds flip chip IC assemblies during the IC manufacturing process according to the prior art.
FIG. 4 is a simplified plan view of the flip chip IC assembly after being spun or agitated while submerged horizontally according to the prior art in the IC cleaning solution in the centrifugal cleaner of FIG. 2 .
FIG. 5 is a simplified perspective view of a cleaning fixture for a centrifugal IC cleaner that employs cassettes that hold IC assemblies at an incline from horizontal according to an embodiment of the invention.
FIG. 6 is a simplified perspective view of a cleaning fixture for a centrifugal IC cleaner that employs IC boats containing IC assemblies, with the IC assemblies being held at an incline from horizontal according to an embodiment of the invention.
FIG. 7 is a simplified perspective view of a cleaning fixture for a centrifugal IC cleaner that holds the IC assemblies directly at an incline from horizontal according to an embodiment of the invention.
FIG. 8 is a flow chart of a method of cleaning IC assemblies according to an embodiment of the invention.
DETAILED DESCRIPTION
An IC assembly cleaning apparatus according to an embodiment of the invention utilizes a version of centrifugal cleaner 200 (of FIG. 2) having a cleaning fixture that holds IC assemblies to be cleaned at an incline from horizontal. (All of the embodiments discussed below involve a centrifugal cleaner, although other type of IC cleaners may also utilize the principles of the invention described herein.) The IC assemblies define a narrow space that contains flux residue to be removed. As described earlier, one such type of IC assembly is flip chip assembly 100 (of FIG. 1 ), in which die 110 and substrate 120 define substantially planar space 140 , which contains flux residue to be removed before space 140 is filled with an adhesive. In one embodiment, depicted in FIG. 5, a first cleaning fixture 500 employs removable cassettes 510 that are attached to a central carousel 520 . Each cassette 510 holds several flip chip assemblies 100 at an incline of approximately 30 degrees from horizontal. In another embodiment, shown in FIG. 6, a second cleaning fixture 600 is capable of holding one or more IC assembly boats 300 (from FIG. 3 ), each of which may hold several flip chip assemblies 100 to be cleaned. Boats 300 are attached to cleaning fixture 600 via slots 610 . In the particular embodiment of FIG. 6, boat 300 is held at an incline of 45 degrees from horizontal. In another embodiment, a third cleaning fixture 700 holds flip chip assemblies 100 directly in a circular fashion in slots (not shown). In the particular embodiment of FIG. 7, flip chip assemblies 100 are maintained at an angle of 90 degrees from horizontal. With respect to any of the embodiments of FIGS. 5, 6 , and 7 , the IC assembly cassettes or boats may be held within the cleaning fixture using methods employed in prior art cleaning fixtures that orient the IC assemblies horizontally. Additionally, other cleaning fixture configurations not specifically mentioned herein may also be utilized, provided that the IC assemblies are held at an angle from horizontal.
Flip chip assemblies 100 , while held at an incline from horizontal, are placed in contact with the surface of a bath of IC cleaning solution 220 in tank 210 (from FIG. 2 ). According to one embodiment, cleaning fixture 500 , 600 , or 700 is lowered into tank 210 that is already filled with cleaning solution 200 . More likely, cleaning fixture 500 , 600 , or 700 is first lowered into an empty tank 210 , and then tank 210 is filled with cleaning solution 220 until the surface of cleaning solution 220 makes contact with flip chip assemblies 100 such that cleaning solution 220 enters planar space 140 , possibly being drawn into planar space 140 by capillary action. While cleaning solution 220 is filling planar space 140 , at least some of the perimeter of planar space 140 is not submerged in cleaning solution 220 , due to the inclined orientation of planar space 140 . The inclined position of flip chip assemblies 100 allows any air within planar space 140 to escape while cleaning solution 220 continues to enter planar space 140 .
To allow air to escape from planar space 140 , flip chip assemblies 100 must be positioned in cleaning solution 220 such that only a portion of the perimeter of planar space 140 is submerged. This positioning is accomplished in one embodiment by controlling the descent of flip chip assemblies 100 into cleaning solution 220 , in the case that tank 210 is already filled with cleaning solution 220 . Alternately, in the case that cleaning fixture 500 , 600 , or 700 already resides within tank 210 , the filling of tank 210 with cleaning solution 220 is controlled so that the surface of the bath of cleaning solution 220 rises slowly enough to allow planar space 140 to be completely filled with cleaning solution 220 prior to the entire perimeter of planar space 140 becoming submerged, thus allowing all air in planar space 140 to escape prior to submergence.
In the embodiment of FIG. 6, second cleaning fixture 600 employs an incline of 45 degrees from vertical. In several embodiments, this angle is thought to be a fair compromise between the needs of a higher angle for purposes of reducing the time to fill solvent tank 210 (or increasing the speed with which the cleaning fixture may be lowered into cleaning solution 220 ) and the desire of a lower angle to facilitate the agitation or centrifugal extraction of cleaning solution 220 , depending on the particular configuration of the cleaning fixture. However, other angles of inclination, ranging from a slight tilt from horizontal to a fully vertical position, will also work well, such as the 30 degrees utilized in first cleaning fixture 500 , or the 90 degrees employed in third cleaning fixture 700 .
Both the agitation of flip chip assemblies 100 and the extraction of cleaning solution 220 from flip chip assemblies 100 are affected by the angle of incline and the angle of orientation with respect to the rotational axis of the particular cleaning fixture. For example, third cleaning fixture 700 provides excellent extraction because the parts are held radially with respect to the rotational axis. However, that same fixture provides poor agitation because of that same orientation. Agitation may be improved, however, by reducing the angle of incline, at the possible expense of a reduced rate of filling planar space 140 .
Furthermore, each embodiment shown in FIGS. 5, 6 , and 7 is not limited to the angle of incline shown for that particular fixture. For example, second cleaning fixture 600 could have been designed to hold flip chip assemblies 100 at an incline of 60 degrees or any other angle deemed necessary for proper cleaning.
Additionally, other embodiments of the present invention take the form of a method of cleaning an IC assembly, such as a flip chip assembly, that allows flux residue to be removed from tight spaces of the IC assembly. FIG. 8 displays the steps involved in a method embodiment of the invention. First, the IC assembly to be cleaned, such as a flip chip assembly with a substantially planar space, for example, is held at an incline from horizontal so that the top surface of a bath of cleaning solution coming in contact with the IC assembly may enter the space without submerging the entire perimeter of the space in the cleaning solution (step 800 ). Next, the IC assembly is immersed in the cleaning solution at a slow enough rate to allow the cleaning solution to fill the space while allowing air within the space to escape or vent without being impeded by the cleaning solution (step 810 ). The IC assembly should not be completely submerged in the cleaning solution until the space has been filled with the solution. Afterward, the steps of moving (via spinning or agitation) the IC assembly in the cleaning solution (step 820 ), rinsing the IC assembly with water to help remove the cleaning solution from the IC assembly (step 830 ), and spin-drying the IC assembly to ensure all cleaning solution and water are extracted from the IC assembly (step 840 ), are customarily employed.
From the use of embodiments of the present invention, not only has the ability to clean narrow spaces in flip chip assemblies been enhanced greatly, but manufacturing line throughput has been increased significantly. Although the time required to fill the tank of a centrifugal cleaner has been increased due to the time needed to allow the cleaning solution to completely fill the thin space of the IC assembly, the amount of time required for spinning and agitating the IC assembly within the cleaning solution has been reduced dramatically since the cleaning solution reaches all of the flux residue within the space. Current use of embodiments of the invention described herein have allowed a previous cleaning cycle time of 15 minutes to be reduced to less than 12 minutes, thus boosting cleaning process throughput by about 25%. Since the IC cleaning process is a significant limiting factor in overall IC manufacturing throughput, such a reduction in the cleaning process cycle time increases the capacity of the entire IC manufacturing line substantially. | An integrated circuit assembly cleaning apparatus and method allow a cleaning solution to completely fill spaces within an integrated circuit assembly. Such spaces include, for example, the thin space between the die and substrate of a flip-chip integrated circuit. The cleaning solution fills the space while the air initially occupying the space escapes. These actions are accomplished by first tilting the integrated circuit assembly from horizontal. The integrated circuit assembly is then immersed in the bath at a controllable rate to allow the cleaning solution to completely fill the space while the air in the space escapes. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 60/991,472, filed Nov. 30, 2007. The disclosure of the above application is incorporated herein by reference,
FIELD
[0002] The present disclosure relates to a motor and pump assembly and more particularly to a motor and pump assembly having improved sealing characteristics which reduce through flow when it is not operating.
BACKGROUND
[0003] The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
[0004] Pumps for fluids encompass a broad range of mechanical configurations and flow characteristics. One frequent pump flow design requirement is constant or non-pulsating flow. This requirement generally eliminates piston pumps which typically have one or more reciprocating pistons producing a pulsating flow and pressure output. Centrifugal pumps provide a significantly smoother output flow but exhibit performance characteristics that vary widely with speed.
[0005] Gerotor and gear pumps represent a middle ground between the foregoing conflicting performance criteria. On the one hand, their construction, which includes two rotating and meshing members, provides a relatively smooth, i.e., non-pulsating, output. On the other, since the pump is essentially a positive displacement type, its speed versus flow and pressure characteristics are essentially proportional. Accordingly, gerotor and gear pumps find wide use in applications requiring a straightforward design, extended service life, minimal pulsation and predictable flow characteristics.
[0006] Occasionally, an issue arises with gerotor and gear pumps with regard to sealing between the meshing members and its influence on through flow. i.e., forward and especially reverse flow, when the pump is not operating. Aside from negligible flow between the side and end surfaces of the members and the stationary housing, the most significant flow occurs between the meshing or nearly meshing members. Depending upon the positions of the members and, more specifically, the extent to which any reverse (or forward) flow and pressure is capable of back driving the pump members, there may be an opportunity for relatively significant backward or forward flow through the non-operating pump. Such flow through a non-operating pump is generally undesirable especially in parallel pump installations or installations where air may be drawn through the non-operating pump into the suction side of the operating pump.
SUMMARY
[0007] The present invention provides a motor and pump assembly that provides reduced forward or reverse leakage through the pump when it is not operating. The present invention comprehends a gerotor or gear pump driven by a permanent magnet motor which exhibits cogging torque, i.e., resistance to rotation when de-energized caused by interaction between permanent magnets in the rotor and teeth on the stator. Such interaction causes the rotor to come to rest in one of many defined rotational positions and resist rotation when electrical power to the motor has been terminated. The permanent magnet motor is coupled, preferably directly, to a gerotor pump having meshing rotors or a gear pump having meshing gears. When the motor is de-energized, the pump rotors or gears come to rest and their rotation is resisted by the cogging torque of the motor. If the permanent magnet motor is a multiple phase design, additional rotation resisting torque may be generated by energizing one phase of the multiple phase motor. Internal friction within the pump caused by fluid pressure on the pump rotors or gears also inhibits their rotation. The invention finds particular application in automotive transmissions and systems with parallel pumps. It should be appreciated that in addition to gerotor and gear pumps, the present invention encompasses the combination of a permanent magnet motor with any type of positive displacement pump.
[0008] Thus it is an object of the present invention to provide a motor and positive displacement pump assembly which achieves minimum through flow when the motor is de-energized.
[0009] It is a further object of the present invention to provide a motor and gerotor or gear pump assembly having a permanent magnet motor which resists rotation of the rotors or gears when the motor is de-energized.
[0010] It is a still further object of the present invention to provide a motor and gear or gerotor pump assembly having a permanent magnet motor which resists rotation of the pump gears or rotors when one phase of a three phase motor is energized.
[0011] It is a still further object of the present invention to provide a motor and pump assembly having minimum through flow in a de-energized state which is especially suited for use in parallel pump installations.
[0012] It is a still further object of the present invention to provide a motor and gerotor pump assembly having gears which resist rotation when the motor is de-energized due to increased internal friction caused by fluid pressure acting on the stationary gears.
[0013] Further objects, advantages and areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
[0014] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
[0015] FIG. 1 is a schematic view of an automatic transmission having two hydraulic pumps disposed in parallel;
[0016] FIG. 2 is an exploded perspective view of a permanent magnet motor according to the present invention;
[0017] FIG. 3 is an exploded perspective view of a permanent magnet motor stator according to the present invention;
[0018] FIG. 4 is an exploded perspective view of a permanent magnet motor rotor according to the present invention; and
[0019] FIG. 5 is an end elevational view of a gerotor pump according to the present invention.
DETAILED DESCRIPTION
[0020] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
[0021] With reference now to FIG. 1 , an automatic transmission incorporating the present invention is illustrated and generally designated by the reference number 10 . The automatic transmission 10 includes a metal housing 12 having a plurality of openings, bores, shoulders, flanges and other features which locate, support and secure various components such as, for example, an input shaft 14 and an output shaft 16 . The lowest portion of the housing 12 defines a sump 18 which collects hydraulic fluid from the various hydraulic components of the automatic transmission 10 . A filter 24 is submerged in the sump 18 and removes particulate matter from hydraulic fluid drawn into a bifurcated suction or inlet line 26 and provided to a first gear pump assembly 30 and a second gerotor or gear pump assembly 40 . The first gear pump assembly 30 includes a first gear pump driven by a component of the automatic transmission 10 and provides pressurized hydraulic fluid in a first output or supply line 34 . The second gerotor or gear pump assembly 40 includes a second gerotor pump 42 driven by a permanent magnet electric motor 44 and provides pressurized hydraulic fluid in a second output or supply line 46 . If desired, a check valve 48 may be disposed at the junction of the supply lines 34 and 46 to reduce back flow to and through the non-operating pump assembly 30 or 40 . The first and second supply lines 34 and 46 provide such hydraulic fluid to a transmission controller 50 which includes a plurality of control valves, spool valves and passageways that provide fluid outputs that control various torque transmitting devices such as clutches and brakes in the automatic transmission 10 to achieve operation. Typically, and as illustrated, the supply lines 34 and 46 will combine, either before or within the transmission controller 50 .
[0022] It will be appreciated that the first gear pump assembly 30 and the second gerotor or gear pump assembly 40 are both utilized in a single automatic transmission 10 to provide different pumping or flow characteristics. For example, since the first gear pump assembly 30 is driven by a component of the automatic transmission 10 , it will provide pressurized hydraulic fluid only when such component is rotating whereas the second gerotor pump assembly 40 may be activated or energized as desired or needed to provide pressurized hydraulic fluid. Alternatively, the first gear pump assembly 30 may have higher flow and lower pressure output than the second gerotor pump assembly 40 or vice versa or the second gerotor pump assembly 40 may have better cold temperature pumping characteristics than the first gear pump assembly 30 . In any event, it is envisioned that two pumps disposed on parallel will be utilized in the automatic transmission 10 to provide desirable and distinct hydraulic fluid pumping characteristics.
[0023] In such an installation, it is highly desirable to reduce or eliminate hydraulic fluid flow through the quiescent, i.e., at rest, gerotor pump assembly 40 . As explained above, the present invention is so directed. In this regard, it should be appreciated that while the present invention is especially suited for and described in conjunction with a parallel pump arrangement in an automatic transmission, the invention is equally suitable for use in other devices and in single, i.e., not parallel, or in multiple parallel installations where reduction in flow through the pump or pumps, especially reverse or back flow, when they are not operating, is either desirable or necessary. Moreover, it should be appreciated that while the second pump assembly 40 is described and referenced primarily as a gerotor pump, gear pumps and other positive displacement pumps are within the purview of the present invention.
[0024] Referring now to FIGS. 2 , 3 and 4 , the permanent magnet motor 44 of the second gerotor pump assembly 40 which drives the gerotor or gear pump 42 is illustrated. The electric motor 44 is disposed within and protected by a cylindrical housing 54 which supports a stator 56 of the electric motor 44 . As illustrated in FIG. 3 , the stator 56 comprises a metal stator core 58 defining a plurality of axially extending T-shaped teeth 62 . In the current motor design, eighteen T-shaped teeth 62 are utilized in the stator core 58 but it should be understood that more or fewer teeth 62 may be utilized. A plurality of slot liners 64 are received between the teeth 62 and a like plurality of electrical windings 66 are disposed within the slot liners 64 between the teeth 62 . The electrical windings 66 may be arranged and connected in either a single or multiple, for example, three, phase configuration. A pair of insulating end caps or spiders 68 complete the stator 56 and protect the electrical windings 66 .
[0025] Rotatably disposed within the stator 56 is a rotor 72 . The rotor 72 includes a cylindrical rotor core 74 which contains a plurality of, for example, twelve, permanent magnets 76 . It will be appreciated that more or fewer permanent magnets 76 may be utilized in the rotor core 74 . The permanent magnets 76 are arranged with circumferentially alternating north and south poles around the rotor core 74 . A balance ring 78 is secured to each end face of the rotor core 74 and the rotor 72 is disposed upon and secured to a stepped drive shaft 82 , illustrated in FIG. 2 .
[0026] Referring now to FIGS. 1 , 2 and 5 , the gerotor pump 42 is disposed at one end of and secured to the cylindrical housing 54 of the permanent magnet motor 44 by suitable means (not illustrated) and includes a cylindrical housing 90 which freely rotatably receives an outer rotor 92 surrounding and driven by an inner rotor 94 which is, in turn, driven by the stepped drive shaft 82 of the permanent magnet motor 44 . At one side of a pumping chamber 96 defined by the inner surface of the outer rotor 92 and the outer surface of the inner rotor 94 is an inlet or suction port 98 . On the opposite side of the pumping chamber 96 is an outlet or pressure port 102 .
[0027] The permanent magnet motor 44 also includes a plurality of ball bearing assemblies 104 associated with the stepped drive shaft 82 as well as fluid seals 106 , a bearing preload washer 108 and an end cap 110 secured to the cylindrical housing 54 by a plurality of threaded fasteners 112 .
[0028] Pumping operation of the second gerotor pump assembly 40 is essentially conventional. When, however, the flow of electrical power to the permanent magnet motor 44 is terminated, the magnetic force from the permanent magnets 76 will align the rotor 72 with the T-shaped teeth 62 of the stator 56 and thereby produce a rotation resisting torque, the cogging torque of the motor 44 . This cogging or rotation resisting (braking) torque is generally sufficient to prevent rotation of the pump rotors 92 and 94 and thus flow through the gerotor pump 42 , particularly reverse or backflow. This rotation resisting torque is augmented by friction or binding torque generated by the rotors 92 and 94 when stationary and subjected to reverse (or forward) fluid pressure.
[0029] It should be understood that if sufficient rotation resisting (braking) torque is not generated by the permanent magnet motor 44 in its deactivated or de-energized state, such that fluid pressure exerted on the outer rotor 92 and the inner rotor 94 of the gerotor pump 42 is sufficient to rotate the rotors 92 and 94 and cause undesirable flow through the gerotor pump 42 , one of the electrical windings 66 of a three phase permanent magnet motor 44 may be energized to increase braking torque to maintain the rotor 72 of the permanent magnet motor 44 and the rotors 92 and 94 of the gerotor pump 42 stationary.
[0030] It should also be understood that with the inner rotor 94 as well as the outer rotor 92 stationary due to the cogging torque of the permanent magnet motor 44 , fluid pressure in the outlet port 102 and the associated output or supply line 46 may be maintained at a low, positive value with a feed from a pressurized circuit such as the output of the first gear pump assembly 30 . This low, positive pressure at the outlet port 102 eliminates the potential for air leakage into the common suction line 26 which is undesirable.
[0031] Finally, it should be understood that while the invention has been described primarily in connection with a gerotor pump, it is equally adapted to and will provide the same benefits when using a gear pump and, in fact, any positive displacement pump.
[0032] The description of the invention is merely exemplary in nature and variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | The present invention comprehends a gerotor or gear pump driven by a permanent magnet motor which exhibits cogging torque, i.e., resistance to rotation when de-energized caused by interaction between permanent magnets in the rotor and teeth on the stator. Such interaction causes the rotor to come to rest in one of many defined rotational positions and resist rotation when electrical power to the motor has been terminated. The permanent magnet motor is coupled, preferably directly, to a gerotor pump having meshing rotors or a gear pump having meshing gears. When the motor is de-energized, the pump rotors or gears come to rest and their rotation is resisted by the cogging torque of the motor. The invention finds particular application in automotive transmissions and systems with parallel pumps. | 5 |
CLAIM OF PRIORITY
[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) to provisional U.S. Patent Application No. 61/687,720, filed on Apr. 30, 2012, the entire contents of which are hereby incorporated by reference.
FIELD OF USE
[0002] The present disclosure relates generally to an ingestible, electrical device, and specifically to an electrical device that stimulates tissues of a gastrointestinal tract of an organism.
BACKGROUND
[0003] In gastric bypass surgery, a surgeon reduces the volume of the stomach by suturing off a large section of the stomach. A portion of the small intestine is then resected, and the remaining organ structure is ligated to the stomach. The result of this therapy is that the amount of food that patients may consume at one time is restricted and the allowed time for nutrient absorption is dramatically reduced. Although effective, this procedure produces debilitating and dangerous side effects such as malnutrition and death.
SUMMARY
[0004] The present disclosure describes apparatus and methods relating to an ingestible, electrical device that stimulates tissues of a gastrointestinal tract of an organism. The device includes a stimulation electrode that provides a current, a voltage, or both to the tissue of the organism and a component for generating the current, the voltage, or both.
[0005] In one aspect of the present disclosure, an ingestible, electrical device, comprises one or more electrodes comprising a biocompatible conducting material and a biocompatible insulating material; a generator connected to the one or more electrodes, with the generator being configured to deliver one or more of a current or a voltage across the one or more electrodes to stimulate one or more internal cells of an organism that ingests the ingestible, electrical device; and an outer casing enclosing the one or more electrodes and the generator, the outer casing configured to dissolve in an aqueous environment of the organism; wherein the one or more electrodes have a first form factor when enclosed in the outer casing and a second form factor following a dissolution of the outer casing, wherein the first form factor is a form factor that is collapsed an increased amount relative to an amount of that the second form factor is collapsed, and wherein the second form factor is a form factor that is collapsed a decreased amount relative to an amount that the first form factor is collapsed.
[0006] Implementations of the disclosure can include one or more of the following features. The one or more electrodes may include a complementary anode cathode pair. The biocompatible conducting material may include at least one of a bioinert metal or a conducting polymer. The bioinert metal may include at least one of copper, gold, magnesium, silver, platinum, or zinc. The biocompatible insulating material may include a bioexcretable copolymer. The bioexcretable copolymer comprises at least one of polyester, polyanhydride, polyamide, polyether, polyphosphoester, polyorthoester, poly(ε-caprolactone) (PCL), or poly(ethylene glycol) (PEG). In some implementations, the generator includes a water-activated battery comprising one or more biocompatible materials. In some implementations, the generator includes a receiver coil and a rectifying circuit, each of the receiver coil and the rectifying circuit comprising one or more of a biodegradable material and a bioinert metal, the receiver coil configured to receive a near-field radio frequency signal, and the rectifying circuit configured to convert energy from the near-field radio frequency signal into the one or more of the current or the voltage. In some implementations, the generator includes one or more fuel cells. The generator may be configured to provide up to 0.1 mA of current for up to 90 minutes. The outer casing comprises at least one of gelatin, synthetic alphahydroxy polymer, crosslinked carbohydrate, polyester, polyanhydride, polyamide, polyether, polyphosphoester, polyorthoester, poly(-caprolactone) (PCL), or poly(ethylene glycol) (PEG). A timing of the dissolution of the outer casing may be based on a thickness of and a degree of crosslinking within a material of the outer casing. The ingestible, electrical device may be an electrical device that stimulates one or more internal cells of a gastrointestinal tract of the organism. The first form factor of the one or more electrodes may be formed by configuring the one or more electrodes into a planar geometry and straining the one or more electrodes equibiaxially during deposition of the bioinert metal to promote thin film metallic buckling of the one or more electrodes.
[0007] In another aspect of the present disclosure, a method performed by an ingestible, electrical device, comprises following a dissolution of an outer casing of the ingestible, electrical device, expanding a form factor of one or more electrodes included in the ingestible, electrical device; wherein at least one of the one or more electrodes comprises a biocompatible conducting material and a biocompatible insulating material; and wherein the dissolution occurs in an organism that ingests the ingestible, electrical device; activating, based on exposure to an aqueous environment in the organism, a generator of the ingestible, electrical device, the generator being connected to the one or more electrodes; following activation of the generator, delivering one or more of a current or a voltage across the one or more electrodes of the ingestible, electrical device; stimulating, based on delivery of the one or more of the current or the voltage, one or more internal cells of the organism that ingests the ingestible, electrical device; and ceasing to deliver the one or more of the current or the voltage across the one or more electrodes after a predetermined time; wherein the ingestible, electrical device may be configured to break down following a cease in delivery of the one or more of the current or the voltage.
[0008] Implementations of the disclosure can include one or more of the following features. The method includes causing, based on stimulating, a decrease in an amount of intestinal motility in the organism relative to an amount of intestinal motility in the organism prior to stimulation. The ingestible, electrical device may be an electrical device that stimulates one or more internal cells of a gastrointestinal tract of the organism. The biocompatible conducting material may include at least one of a bioinert metal or a conducting polymer. The bioinert metal may include at least one of copper, gold, magnesium, silver, platinum, or zinc. The biocompatible insulating material may include a bioexcretable copolymer. The bioexcretable copolymer may include at least one of polyester, polyanhydride, polyamide, polyether, polyphosphoester, polyorthoester, poly(-caprolactone) (PCL) or poly(ethylene glycol) (PEG). In some implementations, the generator includes a water-activated battery comprising biocompatible materials. In some implementations, the generator includes a receiver coil and a rectifying circuit, each of the receiver coil and the rectifying circuit comprising one or more of a biodegradable material and a bioinert metal, the receiver coil configured to receive a near-field radio frequency signal, and the rectifying circuit configured to convert energy from the near-field radio frequency signal into the one or more of the current or the voltage. In some implementations, the generator includes one or more fuel cells. The generator may be configured to provide up to 0.1 mA of current for up to 90 minutes. The outer casing may include at least one of a gelatin material, a synthetic alphahydroxy polymer, a crosslinked carbohydrate, polyester, polyanhydride, polyamide, polyether, polyphosphoester, polyorthoester, poly(-caprolactone) (PCL), or poly(ethylene glycol) (PEG). A timing of the dissolution of the outer casing may be based on a thickness of and a degree of crosslinking within a material of the outer casing.
[0009] In yet another aspect of the present disclosure, a gastroelectrical stimulation (GES) device, comprises one or more electrodes comprising gold deposited on a poly(ε-caprolactone) (PCL) and poly(ethylene glycol) (PEG) copolymer, the one or more electrodes configured to stimulate one or more internal cells of an organism that ingests the GES device to cause a decrease in an amount of intestinal motility in the organism relative to an amount of intestinal motility in the organism prior to stimulation; a water-activated battery comprising one or more biocompatible materials, the water-activated battery connected to the one or more electrodes, with the water-activated battery being configured to deliver a current of up to 0.1 mA for up to 90 minutes across the one or more electrodes to stimulate the one or more internal cells of the organism that ingests the GES device; and an outer casing comprising gelatin material in a capsule form, the outer casing enclosing the one or more electrodes and the water-activated battery, the outer casing configured to dissolve in an aqueous environment of the organism, with a timing of a dissolution of the outer casing based on a thickness and a degree of crosslinking within the gelatin material; wherein the electrodes have a first form factor when enclosed in the outer casing and a second form factor following the dissolution of the outer casing, wherein the first form factor is a form factor with an decreased amount of expansion relative to an amount of expansion of the second form factor, and wherein the second form factor is a form factor with an increased amount of expansion relative to an amount of expansion of the first form factor.
[0010] The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE FIGURES
[0011] FIG. 1 shows an example of an ingestible, electrical device in a condensed geometry packaged into an orally ingestible capsule.
[0012] FIG. 2 shows the ingestible, electrical device of FIG. 1 in an expanded geometry with deployed electrodes.
[0013] FIG. 3 shows an ingestible, electrical device during different stages of operation.
[0014] FIG. 4 shows a progression of an ingestible, electrical device through a gastrointestinal tract of an organism.
[0015] FIG. 5 is a flowchart of operations performed by an ingestible, electrical device.
[0016] FIG. 6 shows an ingestible, electrical device during different stages of fabrication.
DETAILED DESCRIPTION
[0017] An ingestible, electrical device consistent with this disclosure may provide GES that can be administered orally. The ingestible, electrical device may include a stimulation electrode and a generator. The generator provides a current, a voltage, or both to the stimulation electrode to stimulate tissues of a gastrointestinal (GI) tract of an organism. In this context, stimulate includes a change in local properties based on a delivery of a voltage or a current. The device poses minimal risk to an organism, especially in the context of consuming the device for chronic management of obesity. While this disclosure describes an ingestible, electrical device in the context of coordinated simulation for obesity treatment, the apparatus and methods described in the present disclosure could also be used to treat a wide range of food metabolism pathologies.
[0018] The ingestible, electrical device may be fabricated into a form factor that can be delivered orally and easily swallowed. The ingestible, electrical device may be fabricated from materials that are biodegradable and endogenous to an organism that ingests the device. Biodegradable devices reduce the risk associated with permanent devices including possible build-up and obstruction in the GI tract. Additionally, finite device lifetimes limit the potential toxicity profile associated with ingesting multiple devices over a sustained period of time.
[0019] FIG. 1 shows an example of an ingestible, electrical device 100 in a condensed (consolidated, compressed, or collapsed) geometry packaged into an orally ingestible capsule. When packaged in an outer casing 101 , the device 100 may take the approximate shape of a rectangular prism with a length of 2 cm, a width of 0.8 cm, and a height of 0.8 cm, which is approximately the size of a large pill to be taken orally. The device 100 includes non-toxic materials that can be absorbed, metabolized, or excreted by an organism, e.g., a human or other animal, that ingests the device 100 . FIG. 1 will be described in conjunction with FIG. 2 , which shows the ingestible, electrical device 100 in an expanded (or swollen) geometry with deployed electrodes 102 , 104 , 106 , and 108 . In addition to the electrodes 102 , 104 , 106 , and 108 , the device 100 includes a generator 110 .
[0020] The outer casing 101 encloses the device components, such as the electrodes 102 , 104 , 106 , and 108 , and the generator 110 . The outer casing 101 may protect the device components as the device 100 passes through a stomach and into a small intestine of an organism to ensure that the device 100 is not subjected to caustic environments. The outer casing may serve as a time protective retainer that keeps the electrodes 102 , 104 , 106 , and 108 in the condensed geometry until it reaches an area of interest within the GI tract of the organism. The material of the outer casing 101 can be engineered to dissolve within a precisely defined time line. After dissolution, the outer casing 101 can be absorbed and metabolized by the organism, or excreted by the organism with other non-absorbed device components.
[0021] The outer casing 101 of the device 100 may include, for example, gelatin in a capsule form similar to those commonly used in existing oral pill formulations. The timing of the device expansion or swelling is controlled by engineering the thickness and degree of crosslinking within the gelatin layer. The outer casing 101 may include other suitable materials such as synthetic alpha-hydroxy polymers, crosslinked carbohydrates, polyesters, polyanhydride, polyamides, polyethers, polyphosphoesters, polyorthoesters, poly(ε-caprolactone) (PCL), or poly(ethylene glycol) (PEG).
[0022] The electrodes 102 , 104 , 106 , and 108 have a condensed geometry when packaged in the outer casing 101 as shown in FIG. 1 , and have an expanded or swollen geometry following dissolution of the outer casing 101 as shown in FIG. 2 . The electrodes 102 , 104 , 106 , and 108 may include conducting materials 102 a , 104 a , 106 a , and 108 a such as bioinert metals or conducting polymers. Examples of bioinert metals include copper, gold, magnesium, silver, platinum, and zinc.
[0023] The electrodes 102 , 104 , 106 , and 108 may be shape-memory electrodes fabricated from insulating materials 102 b , 104 b , 106 b , and 108 b such as copolymers based on poly(ε-caprolactone) (PCL), poly(ethylene glycol) (PEG), or a combination. PCL and PEG copolymers are thermally actuated to deploy the electrodes 102 , 104 , 106 , and 108 through expansion. PCL is biodegradable, and PEG is bioexcretable. PCL and PEG have both been extensively utilized in medical devices that have been FDA-approved for various applications as surgical materials, drug delivery systems, and scaffolds for tissue regeneration. The electrodes 102 , 104 , 106 , and 108 may include other suitable insulating materials such as polyesters, polyanhydride, polyamides, polyethers, polyphosphoesters, polyorthoesters, or a combination. Poly(ester amide) networks are both elastomeric and biodegradable. Biodegradable shape-memory elastomer electrodes synthesized from poly(ester amide) networks can be actuated through rubbery-glassy transitions via hydration to deploy the electrodes 102 , 104 , 106 , and 108 through swelling. Another example of a suitable material for the electrodes 102 , 104 , 106 , and 108 may include a superabsorbent polymer such as a hydrogel. In this example, the electrodes 102 , 104 , 106 , and 108 may deploy by swelling due to hydrolysis. Other mechanisms for deployment of the electrodes 102 , 104 , 106 , and 108 may be based on environmental factors such as changes in potential hydrogen (pH), changes in temperature, and other environmental factors.
[0024] The generator 110 is connected to the electrodes 102 , 104 , 106 , and 108 to provide a current, a voltage, or both to the electrodes 102 , 104 , 106 , and 108 . The generator 110 may be composed of non-toxic biomaterials that can be absorbed as nutrients or excreted as waste. The generator 110 may be an on-board power supply for autonomous power generation or electronically active structures that are able to harvest externally applied energy which can be converted into electric current, voltage, or both for tissue stimulation. For example, the device 100 can be powered internally through a biocompatible or biodegradable battery or externally through near-field radiofrequency power transfer. The generator 110 may be configured to provide, for example, up to 0.1 mA of current for up to 90 minutes. The current or voltage may be programmed into arbitrary wave forms including constant, pulsed, and sinusoidal stimulation patterns. The current or voltage can be alternating or direct.
[0025] In some implementations, the generator 110 may be a water-activated biodegradable battery. The low currents and voltages and limited stimulation times of the device 100 allow for incorporation of a small battery to serve as an on-board power supply. The geometry of the battery may be a high-aspect ratio cylinder similar to an oral pill. The battery may be stored in a dry state and coated in a biodegradable poly(L-lactide-co-glycolide) (PLGA) film that is semi-permeable to water. Battery operation is activated once water permeates the PLGA film and wets the aqueous cell. The initiation of battery function is engineered by controlling water permeation in the PLGA casing. Water permeability is controlled through PLGA composition and film geometry. Other suitable material compositions may be used in addition, or as an alternative, to the PLGA film.
[0026] The battery may include a cathode, an anode, and a separator. The cathode may be fabricated from a compound based on sodium and manganese oxide. These cathode materials are able to shuttle sodium ions in aqueous cells with sufficient efficiencies. These cathode materials may be biocompatible. The anode of the battery may be fabricated from activated carbon. Activated carbon is non-toxic and may absorb toxins to replace liver function. The separator may be fabricated from microporous poly(L-lactide). The microporous structure may be achieved by phase inversion via rapid precipitation. The cathode and the anode of the battery are connected to the electrodes 102 , 104 , 106 , and 108 .
[0027] In some implementations, the generator 110 may power the device is through external radiofrequency stimulation. The generator 110 may include a receiver coil and a rectifying circuit. The receiver coil receives a near-field radio frequency signal, e.g., an AC signal, that may be provided by a pack of external coils. The rectifying circuit converts the energy from the near-field radio frequency signal into electric current, e.g., a DC current, or voltage that is used for GES. The receiver coil and the rectifying circuit may include electronically active biodegradable materials, bioinert metals, or a combination. The generator 110 may be devices other than those described above. For example, the generator 110 may be one or more fuel cells that provide power to the device 100 .
[0028] FIG. 3 shows an ingestible, electrical device, e.g., the device 100 of FIG. 1 and FIG. 2 , during different stages (a)-(d) of operation. FIG. 3 will be described in conjunction with FIG. 4 , which shows a progression of the device 100 through a gastrointestinal (GI) tract 400 of an organism during the different stages (a)-(d) of operation. The device 100 progresses through the GI tract 400 in a consolidated form factor via natural digestion. The device 100 can be selectively deployed and activated anywhere within the GI tract 400 through careful selection of materials and design of a geometry of the device 100 . For example, rapidly dissolvable packaging materials may be suitable for device deployment in a section of the small intestines 404 , e.g., the duodenum, while more slowly degrading materials may be suitable for device deployment in a section of the large intestines 406 such as the colon.
[0029] In stage (a), the components of the device 100 are enclosed in and protected by the outer casing 101 , and the device 100 is inactive. In this context, inactive refers to not being functional as in the case when the generator 110 is not supplying power to the electrodes 102 , 104 , 106 , and 108 of the device 100 . The device 100 may be in stage (a) while the device 100 is passing through a stomach 402 and into a small intestine 404 of the organism. The outer casing 101 can be engineered to dissolve within a precisely defined time line. Precisely timed dissolution of the outer casing 101 liberates the device 100 in a predetermined location with the GI track 400 .
[0030] The device 100 progresses to stage (b) after the device 100 passes through the stomach 402 and into the small intestine 404 of the organism. The outer casing 101 may have completely dissolved after passing through the stomach 404 . After dissolution of the outer casing 101 , the components of the device 100 are exposed to high salinity aqueous environments with elevated temperatures within the small intestine 404 of the organism.
[0031] At stage (c), elevated temperatures and hydration initiate shape change routines in the electrodes 102 , 104 , 106 , and 108 . The electrodes 102 , 104 , 106 , and 108 deploy by expanding, unfurling, or swelling. Water diffuses across a polymeric casing of the generator 110 and initiates activation of the generator 110 . In the case where the generator 110 is a water-activated battery, hydration of the battery initiates activation of the wet cell. The battery transitions from an inactive dehydrated state into an active wet-cell battery. The generator 110 delivers a current, a voltage, or both 302 across complementary cathode anode electrode pairs, e.g., electrodes 102 and 104 , or electrodes 106 and 108 . Complementary cathode anode electrode pairs form intimate contact with the soft tissues in the small intestines 404 to stimulate the gastric tissues at the predetermined location of interest. GES may occur for approximately 60 to 120 minutes. In some implementations, the device 100 may continue to progress through the small intestines 404 during GES. In some implementations, the electrodes 102 , 103 , 106 , and 108 may stabilize and anchor the device 100 and retard passage of the device 100 through the GI tract 400 during GES.
[0032] After stimulation, the device 100 ceases to function. The device 100 , including the electrodes 102 , 104 , 106 , and 108 , and the generator 110 , may degrade, or break down, and may lose mechanical resiliency at stage (d) as it progresses toward the end of the large intestine 406 of the GI tract 400 . The materials of the device 100 are absorbed or metabolized, or passed through the remainder of the GI tract 400 through active digestive motion and eventually excreted. The materials of the device 100 are selected such that they can be completely bioabsorbed by the organism or efficiently secreted without any negative health impacts.
[0033] FIG. 5 is a flowchart of operations performed by an ingestible, electrical device. As described above, the process 500 includes expanding a form factor of one or more electrodes included in the device ( 502 ), activating a generator of the device based on exposure to an aqueous environment in the organism ( 504 ), and delivering a current, a voltage, or both across the electrodes of the device following activation of the generator ( 506 ). Based on delivery of the current, the voltage, or both across the electrodes, the device stimulates one or more internal cells of the organism ( 508 ), which may cause a decrease in an amount of intestinal motility in the organism relative to an amount of intestinal motility in the organism prior to stimulation. After a predetermined time of stimulation, the device ceases to deliver the current or the voltage across the electrodes. Following a cease in the delivery of the current or the voltage, the device is configured to degrade or break down.
[0034] FIG. 6 shows an ingestible, electrical device during different stages of fabrication. The device may be fabricated entirely from non-toxic materials, biodegradable materials, or a combination of both. In some implementations, the device components are fabricated using materials that have been incorporated into FDA-approved medical devices. In some implementations, the device components are fabricated using materials that may be used in dietary supplements or other oral treatments such as detoxification.
[0035] In the example of FIG. 6 , insulating materials 602 , e.g., biodegradable shape-memory polymers synthesized from PCL and PEG composites, are injection molded at stage (a) into a final complex 3D geometry, as shown in stage (b). The form factor of the insulating materials 602 is programmed into a planar geometry at stage (c) to facilitate electrode integration. Materials such as poly(ester) amides can be integrated with an electrically conducting material 604 , e.g., a thin gold film. Gold is a bioinert metal that has been used in many medical devices and should pose no risk as a material that is consumed orally. Other suitable conducting materials include other bioinert metals, such as silver and platinum, and conducting polymers. Electrodes 603 are fabricated by thermal deposition or evaporation of the conducting material 604 and patterned using shadow masks at stage (d). At stage (e), the electrodes 603 may be processed into serpentine geometries to enable high density packaging into an outer gelatin capsule. For example, the insulating materials 602 in the planar form factor may be strained equibiaxially during deposition of the conducting material 604 in order to induce thin film buckling. Evaporating rigid films on pre-strained substrates can produce micron-scale buckling features. These corrugated features may help maintain electrical conductivity during deformation of the biodegradable elastomeric electrodes 602 during both packaging and deployment, e.g., during flexion and hydration-induced swelling in the GI tract. The electrodes 603 are connected to a generator 605 .
[0036] A number of implementations have been described. Nevertheless, various modifications can be made without departing from the spirit and scope of the processes and techniques described herein. In addition, the processes depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other steps can be provided, or steps can be eliminated, from the described processes, and other components can be added to, or removed from, the describe apparatus and systems. Accordingly, other embodiments are within the scope of the following claims. | In one aspect, an ingestible, electrical device, comprises one or more electrodes comprising a biocompatible conducting material and a biocompatible insulating material; a generator connected to the one or more electrodes; and an outer casing enclosing the one or more electrodes and the generator, the outer casing configured to dissolve in an aqueous environment of the organism; wherein the one or more electrodes have a first form factor when enclosed in the outer casing and a second form factor following a dissolution of the outer casing, the first form factor is a form factor that is collapsed an increased amount relative to an amount that the second form factor is collapsed, and the second form factor is a form factor that is collapsed a decreased amount relative to an amount that the first form factor is collapsed. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electrode for a lithium secondary battery and a method for producing the same.
2. Related Art
In recent years, development of lithium secondary batteries has been actively made. The battery properties of a lithium secondary battery, such as the charge-discharge voltages, the charge-discharge cycle life characteristics and the storage property, are greatly influenced by the electrode active material used.
Among electrode active materials capable of lithium storage and release, silicon which is a material storing lithium by being alloyed with lithium, has been examined in various aspects because it has a large theoretical capacity. However, since silicon stores lithium by forming an alloy with lithium, the volume greatly expands and shrinks with charge and discharge. This causes problems such as pulverization of the active material and separation of the material from a current collector, and thus deteriorates the charge-discharge cycle characteristics. For this reason, use of silicon has not yet been commercialized.
Electrodes for lithium secondary batteries using silicon and the like as an electrode active material and yet exhibiting a good charge-discharge cycle characteristics have been proposed (International Publication No. WO 0/31720A1), in which a microcrystalline or amorphous thin film is formed on a current collector by a thin film formation method such as a CVD method, a sputtering method and a vapor evaporation method. In such electrodes for lithium secondary batteries, the adhesion between the thin film and the current collector is good because a component of the current collector diffuses into the active material thin film appropriately, and this improves the charge-discharge cycle characteristics. For example, when a thin film made of silicon or germanium is formed on a current collector containing copper, the copper diffuses into the silicon or germanium, improving the adhesion between the thin film and the current collector.
However, since the diffusion coefficient of copper in silicon or germanium is significantly large, an excessive amount of the current collector component may diffuse in the thin film forming an alloy depending on the thin film formation conditions and the type of the current collector used. In such a case, the charge-discharge cycle characteristics may be deteriorated.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an electrode for a lithium secondary battery capable of controlling diffusion of a current collector component and exhibiting an excellent charge-discharge cycle characteristics, and a method for producing the same.
The electrode for a lithium secondary battery of the present invention includes: a current collector; an interlayer containing Mo or W provided on the current collector; and a thin film composed of active material capable of lithium storage and release deposited on the interlayer.
According to the present invention, an interlayer containing Mo or W is provided between the current collector and the thin film of active material. With providing the interlayer, it is possible to suppress diffusion of a current collector component into the thin film appropriately, and thus prevent generation of an adverse effect due to excessive diffusion of the current collector component.
The component of the interlayer is not limited to Mo and W, but substantially the same effect can be obtained by use of at least one kind of metal selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), germanium (Ge), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), silver (Ag), indium (In), tin (Sn), antimony (Sb), tantalum (Ta), tungsten (W) and lead (Pb), an alloy containing at least one kind of metal selected from the above group as a main component, or an oxide, nitride or carbide of any kind of metal selected from the above group.
According to the present invention, the thickness of the interlayer is preferably 0.01 to 1 μm. When a thin interlayer is formed, it does not necessarily cover the entire current collector, but may exist like islands on the current collector. The thickness of the interlayer as used herein is that obtained when the interlayer is deposited on a flat substrate surface. When the surface of the current collector is roughened, an interlayer having a uniform thickness may not be formed. In such a case, the thickness of the interlayer is converted to a thickness to be obtained when the interlayer is deposited on a smooth substrate surface as described above.
The surface of the interlayer in contact with the thin film is preferably roughened. With this roughened surface, the adhesion between the interlayer and the active material thin film is further improved. The surface of the interlayer can be roughened in correspondence with a roughened surface of the current collector. In other words, the surface of the current collector is roughened, and the interlayer is formed on the current collector so that the surface of the interlayer is roughened in correspondence with the surface of the current collector.
The roughened surface of the current collector preferably has a surface roughness Ra of about 0.01 to 2 μm, more preferably 0.1 μm or more, further more preferably about 0.1 to 2 μm. The surface roughness Ra is defined in Japan Industrial Standards (JIS B 0601-1994) and can be measured with a surface roughness meter, for example.
According to the present invention, preferably, the thin film is divided into columns by gaps formed in its thickness direction, and the columnar portions are adhered to the interlayer at their bottoms.
The thin film composed of active material capable of lithium storage and release according to the present invention is preferably a material storing lithium by being alloyed with lithium. Examples of such a material include silicon, germanium, tin, lead, zinc, magnesium, sodium, aluminum, potassium and indium. Among them, silicon and germanium are preferably used due to their large theoretical capacity. Therefore, the active material thin film used in the present invention is preferably a thin film containing silicon or germanium as a main component.
Preferably, the active material thin film is a substantially amorphous or microcrystalline thin film.
Examples of the material of the current collector used in the present invention include copper (Cu), nickel (Ni), stainless steel and tantalum (Ta). The current collector is preferably thin, and therefore preferably in the form of metal foil. The current collector is preferably made of a material which is not alloyed with lithium. Copper (Cu) is especially preferable as the current collector. Thus, current collector is preferably copper foil. As described above, the surface of the current collector is preferably roughened. In consideration of the above, electrolytic copper foil is preferably used because the surface of such foil is roughened. Alternatively, surface-roughened metal foil such as nickel foil with a copper-containing layer formed thereon may be preferably used.
The method for producing an electrode for a lithium secondary battery of the present invention includes the steps of: forming an interlayer containing Mo or W on a current collector; and depositing a thin film composed of active material capable of lithium storage and release on the interlayer.
The interlayer may be formed by a vapor evaporation method, a CVD method, a sputtering method, a plating method or the like, for example.
The active material thin film may be formed by an sputtering method, a CVD method, a vapor evaporation method, a spraying method, a plating method or the like.
In the active material thin film according to the present invention, preferably, gaps are formed in the thickness direction due to volume expansion and shrinkage of the active material with charge-discharge reaction, and the thin film is divided into columns. By dividing into columns due to gaps formed in the thickness direction, spaces are formed around the columnar portions. Therefore, these spaces can accommodate volume expansion and shrinkage with charge-discharge reaction, generation of stress in the thin film can be prevented. This makes it possible to prevent pulverization of the thin film and separation of the thin film from the current collector, and thus improve the charge-discharge cycle characteristics.
The gaps described above are preferably formed toward valleys of the irregularities on the surface of the interlayer in the case that the surface of the interlayer is roughened.
The active material thin film according to the present invention may be made up of a sequence of superimposed layers. The respective layers may differ in composition, crystallinity, element or impurity concentration or the like from one another. Alternatively, the thin film may have a graded structure in the thickness direction. For example, the thin film may have a graded structure varying composition, crystallinity, element or impurity concentration or the like in the thickness direction.
Lithium may previously be stored in or added to the active material thin film according to the present invention. Lithium may be added to the thin film at the time of forming the thin film. In other words, lithium may be added to the thin film by forming a lithium-containing thin film. Alternatively, lithium may be stored in or added to the thin film after forming the thin film. As a method which lithium is stored in or added to the thin film, an electrochemical method may be employed.
The thickness of the active material thin film is not specifically limited, but may be 20 μm or less, for example. For obtaining a larger charge-discharge capacity, the thickness is preferably 1 μm or more.
The lithium secondary battery of the present invention includes a negative electrode made of the electrode of the present invention described above, a positive electrode and a nonaqueous electrolyte.
The solvent of the electrolyte used for the lithium secondary battery of the present invention is not specifically limited, but an example of such a solvent is a mixed solvent of a cyclic carbonate such as ethylene carbonate, propylene carbonate, butylene carbonate and vinylene carbonate, and a chain carbonate such as dimethyl carbonate, methylethyl carbonate and diethyl carbonate. Another example is a mixed solvent of a cyclic carbonate described above with an ether solvent such as 1,2-dimethoxyethane or 1,2-diethoxyethane, or with a chain ester such as γ-butyrolactone, sulfolane or methyl acetate. Examples of a solute of the electrolyte include LiPF 6 , LiBF 4 , LiCF 3 SO 3 , LiN (CF 3 SO 2 ) 2 LiN (C 2 F 5 SO 2 ) 2 , LiN(CF 3 SO 2 ) (C 4 F 9 SO 2 ), LiC(CF 3 SO 2 ) 3 , LiC(C 2 F 5 SO 2 ) 3 , LiAsF 6 , LiClO 4 , Li 2 B 10 Cl 10 , Li 2 B 12 Cl 12 , and mixtures thereof. Examples of the electrolyte include gel polymer electrolyte made of a polymer electrolyte such as polyethylene oxide, polyacrylonitrile and polyvinylidene fluoride impregnated with an electrolyte solution, and an inorganic solid electrolyte such as LiI and Li 3 N. Any electrolyte can be used for the lithium secondary battery of the present invention without limitation as long as a Li compound as the solute developing ion conductivity and the solvent dissolving and retaining the compound are not decomposed under a voltage during charge, discharge or storage of the battery.
Examples of the positive electrode active material of the lithium secondary battery of the present invention include lithium-containing transition metal oxides such as LiCoO 2 , LiNiO 2 , LiMn 2 O 4 , LiMnO 2 , LiCo 0.5 Ni 0.5 O 2 and LiNiO 0.7 Co 0.2 Mn 0.1 O 2 and lithium-free metal oxides such as MnO 2 . Any other materials can also be used without limitation as long as they can insert and deinsert lithium electrochemically.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a scanning electron micrograph of a cross section of an electrode al of the present invention (magnification 2000×).
FIG. 2 is a scanning electron micrograph of a cross section of the electrode a 1 of the present invention (magnification 1000×).
FIG. 3 is a scanning electron micrograph of a cross section of an electrode a 2 of the present invention (magnification 2000×).
FIG. 4 is a scanning electron micrograph of a cross section of the electrode a 2 of the Comparative Example (magnification 1000×).
FIG. 5 is a scanning electron micrograph of a cross section of an electrode b 1 of the Comparative Example (magnification 2000×).
FIG. 6 is a scanning electron micrograph of a cross section of the electrode b 1 of the present invention (magnification 1000×).
FIG. 7 is a view showing the charge-discharge cycle characteristics of electrodes of examples of the present invention.
FIG. 8 is a view showing the charge-discharge cycle characteristics of electrodes of examples of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the present invention will be described in more detail by way of example. Note that the present invention is not restricted to the examples to follow, but any appropriate modification is possible as long as the scope of the invention is not changed.
(Experiment 1)
[Production of Electrodes a 1 and a 2 ]
An Mo layer and a W layer having a thickness of 0.1 μm as an interlayer were respectively formed on the roughened surface of the electrolytic copper foil (thickness: 18 μm) having a surface roughness Ra of 0.188 μm in an argon (Ar) atmosphere by RF sputtering. The thin film formation was performed under the conditions of an RF power of 200 W, an Ar gas flow of 60 sccm, a chamber inner pressure of 0.1 Pa, and room temperature (not heated) as the substrate temperature.
Thereafter, a microcrystalline silicon thin film was formed on each of the Mo layer and the W layer by a CVD method, using silane (SiH 4 ) gas as the material gas and hydrogen gas as the carrier gas. The thin film formation was performed under the conditions of an SiH 4 flow of 10 sccm, an H 2 gas flow of 200 sccm, a substrate temperature of 180° C., a reaction pressure of 40 Pa, and an RF power of 555W.
The microcrystalline silicon thin film was deposited to a thickness of 2 μm under the above conditions, and the resultant silicon thin film was cut into a 2 cm×2 cm piece together with the electrolytic copper foil, to obtain an electrode a 1 formed on the Mo interlayer and an electrode a2 formed on the W interlayer.
[Production of Electrode b 1 ]
An electrode b 1 was produced in the same manner of the electrodes a 1 and a 2 described above, except that a microcrystalline silicon thin film was directly formed on the roughened surface of the above-mentioned electrolytic copper foil with no Mo or W layer therebetween.
[Electron Microscopic Observation of Electrode]
The electrodes a 1 , a 2 and b 1 before assembly into test cells were observed with a scanning electron microscope. FIGS. 1 and 2 are scanning electron micrographs (secondary electron images) of a cross section of the electrode a 1 . FIGS. 3 and 4 are scanning electron micrographs (secondary electron images) of a cross section of the electrode a 2 . FIGS. 5 and 6 are scanning electron micrographs (secondary electron images) of a cross section of the electrode b 1 . The magnification is 2000×for FIGS. 1 , 3 and 5 , while it is 10000×for FIGS. 2 , 4 and 6 .
Each sample observed was prepared by covering the electrode with resin and slicing the resultant electrode. The dark region observed in the upper portion of each of FIGS. 1 to 6 corresponds to the resin cover layer. In FIGS. 1 to 6 , a slightly bright lower portion corresponds to the copper foil, and a somewhat dark portion above the copper foil corresponds to the silicon thin film (thickness: about 2 μm). In FIGS. 1 to 4 , a very thin bright portion is recognized between the copper foil and the silicon thin film. This is the Mo or W layer as the interlayer.
As is shown in FIGS. 1 to 4 , in which the silicon thin film is formed on the copper foil with the Mo or W layer as the interlayer therebetween, the silicon thin film is homogeneous with no particular abnormality recognized in the interface portion of the silicon thin film. On the contrary, as is shown in FIGS. 5 and 6 , in which the silicon thin film is directly formed on the copper foil with no interlayer therebetween, heterogenous portions are observed as somewhat bright portions in the silicon thin film at positions near the interface with the copper foil. It is considered that these portions were formed by excessive diffusion of copper into the silicon thin film. Therefore, it is found that diffusion of the current collector component into the silicon thin film can be suppressed by providing the Mo or W layer as the interlayer between the current collector and the silicon thin film.
[Measurement of Charge-discharge Cycle Characteristics]
Test cells were produced using the above-mentioned electrodes a 1 , a 2 and b 1 respectively as the working electrode, and metal lithium as the counter electrode and the reference electrode. As the electrolyte, an electrolyte obtained by dissolving 1 mol/liter of LiPF 6 in a mixed solvent containing equi-volumes of ethylene carbonate and diethyl carbonate was used. Note that in the single electrode test cells, reduction of the working electrode is referred to as charge, while oxidation thereof is referred to as discharge.
The test cells were charged at a constant current of 2 mA at 25° C. until the potential with the reference electrode as a standard reaches 0 V and then discharged at a constant current of 2 mA at 25° C. until the potential reaches 2 V. The one cycle of charge and discharge was repeated, and the capacity retention rate at each of the first to sixth cycles was measured. The capacity retention rate is a value defined by the equation below. The results are shown in Table 1 and FIG. 7
Capacity retention rate (%)=discharge capacity at each cycle/discharge capacity at the first cycle)×100
TABLE 1
Cycle Number
1
2
3
4
5
6
Capacity Retention
Rate (%)
Electrode a1
100
105
108
108
109
107
Electrode a2
100
102
104
104
105
104
Electrode b1
100
112
106
113
114
116
As is apparent from Table 1 and FIG. 7 , the test cells using the electrodes a 1 and a 2 exhibit cycle characteristics roughly equal to that of the test cell using the electrode b 1 . This indicates that the electrode having the Mo or W layer as the interlayer can exhibit adhesion roughly equal to that of the electrode having no interlayer, in addition to suppressing diffusion of copper into the silicon thin film.
In addition, it was confirmed that the entire electrode b 1 had been embrittled due to a reaction product generated near the interface between the current collector and the silicon thin film, and thus the electrode b 1 was inferior in durability as an electrode for a battery to the electrodes a 1 and a 2 . Accordingly, it is found that by providing an interlayer between the current collector and the active material thin film according to the present invention, it is possible to suppress reaction and diffusion at the interface between the current collector and the active material thin film appropriately, and thus provide an electrode for a lithium secondary battery excellent in charge-discharge cycle characteristics and durability. It is confirmed that such an effect is obtained even when the interlayer is further thinned to about 0.01 μm and does not cover the surface of the current collector completely but exists like islands on the surface of the current collector.
The electrodes a 1 and a 2 after the charge-discharge cycles were observed with a scanning electron microscope. As a result, it was confirmed that gaps were formed in the entire thin film in the thickness direction originating from valleys of the rough surface of the thin film, and the thin film was divided into columns by these gaps.
(Experiment 2)
[Production of Electrodes c 1 and c 2 ]
An Mo layer and a W layer as the interlayer were respectively formed on rolled copper foil (thickness: 18 μm) having a surface roughness Ra of 0.037 m under the same conditions as those in the formation of the electrodes a 1 and a 2 .
Thereafter, a microcrystalline silicon thin film was formed on each of the Mo and W layers under the same conditions as those in the formation of the electrodes a 1 and a 2 . The resultant silicon thin film was cut into a 2 cm×2 cm piece together with the rolled copper foil, to obtain an electrode c 1 with the Mo interlayer and an electrode c 2 with the W interlayer.
[Production of Electrode d 1 ]
An electrode d 1 was produced in the same manner of the electrodes c 1 and c 2 , except that a microcrystalline silicon thin film was directly formed on the rolled copper foil with no Mo or W layer therebetween.
[Measurement of Charge-discharge Cycle Characteristics]
Using the electrodes c 1 , c 2 and d 1 respectively as the working electrode, the charge-discharge cycle characteristics was measured as in Experiment 1 described above. The results are shown in Table 2 and FIG. 8 .
As is shown in Table 2 and FIG. 8 , while the cycle characteristics of test cells using the electrodes c 1 and c 2 are superior to that of a test cell using the electrode d 1 , they are significantly inferior to those of the electrodes a 1 , a 2 and b 1 in Experiment 1. The result indicates that while the charge-discharge characteristics can be improved by using the Mo or W layer as the interlayer, the charge-discharge cycle characteristics can further be improved when the surfaces of the interlayer and the current collector are roughened.
In addition, it was confirmed that the entire electrode d 1 had been embrittled due to a reaction product generated near the interface between the current collector and the silicon thin film, and thus the electrode d 1 was inferior in durability as an electrode for a battery. The embrittlement was more significant than that observed in the electrode b 1 . Actually, the electrode was cracked only by being slightly deformed.
TABLE 2
Cycle Number
1
2
3
4
5
6
Capacity Retention
Rate (%)
Electrode c1
100
88
78
68
55
44
Electrode c2
100
87
73
59
51
41
Electrode d1
100
78
57
44
32
22
In the above examples, the Mo layer and the W layer were used as the interlayer. Alternatively, substantially the same effect can also be obtained by use of an interlayer made of any of metals Mg, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Ge, Zr, Nb, Mo, Ru, Ag, In, Sn, Sb, Ta, W and Pb, alloys containing any of these metals as a main component, and oxides, nitrides and carbides of these metals.
According to the present invention, an electrode for a lithium secondary battery capable of controlling diffusion of a current collector component appropriately and exhibiting an excellent charge-discharge cycle characteristics can be obtained. | The electrode for a lithium secondary battery includes: a current collector; an interlayer containing Mo or W provided on the current collector; and a thin film composed of active material capable of lithium storage and release deposited on the interlayer. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is for a clamping system and, more particularly, is for a system including a variable geometry clamp joining telescoping box tubes, such as for gate arms.
2. Description of the Prior Art
Prior art clamping systems for gate arms were bolted together. The amount of time for assembly in the field was sometimes significant, because it was necessary to drill holes. In later years, the clamping systems came with predrilled holes, but sometimes the predrilled holes did not always align or were not drilled for the proper distances.
The present invention overcomes the problems with the prior art assembly of clamping systems for gate arms by providing a box tube clamping system. SUMMARY OF THE INVENTION
The general purpose of the present invention is to provide a box tube clamping system including telescoping box tubes and an interceding variable geometry clamp. Such joined box tubes can be used for railroad grade crossing arms, parking lot security arms, or other situations requiring the attachment of box tubes or arms along a longitudinal axis. An outer box tube telescopingly accommodates an inner box tube of slightly lesser dimension. The outer box tube and the inner box tube are dimensioned such that substantially planar portions of a variable geometry clamp can be accommodated between the lower planar panels of each of the box tubes. The lower panel of the larger of the box tubes includes an elongated hole through which vertically oriented posts of the variable geometry clamp protrude. The variable geometry clamp is comprised of a center wedge assembly flanked by a left wedge assembly and a right wedge assembly. Each wedge assembly includes a wedge plate having opposing bevels and a holed post extending downwardly from the bottom surface thereof. An upwardly facing bevel of the left wedge plate and an upwardly facing bevel of the right wedge plate align intimately in edge to edge, bevel to bevel, horizontal fashion to oppositely oriented downwardly facing bevels of the center wedge plate. A bolt extending through the holes in the downwardly extending posts is incorporated to draw the left and right beveled wedge plates of the left and right wedge assemblies together against the center wedge plate of the center wedge assembly to alter the geometry of the clamp by causing forced upward deflection of the center wedge assembly by action of the impinging bevels. Such a change to the vertical extent of the variable geometry clamp forces mutual frictional and secure engagement of the inner box tube and the outer box tube.
According to one embodiment of the present invention, there is provided a box tube clamping system for secure joining of telescoping outer nad inner box tubes.
An alternate embodiment discloses installation spacers in the variable geometry clamp which aid in insertion of the inner box tube into the outer box tube.
One significant aspect and feature of the present invention is a box tube clamping system having a variable geometry clamp disposed between like planar panels of telescoping box tubes.
Another significant aspect and feature of the present invention is a variable geometry clamp having a center wedge assembly disposed between adjoining wedge assemblies.
Still another significant aspect and feature of the present invention is the use of wedge assemblies having beveled wedge plates and holed posts extending downward therefrom.
Yet another significant aspect and feature of the present invention is the intimate horizontal alignment of beveled surfaces of the beveled wedge plates.
A further significant aspect and feature of the present invention is the forcing together of adjoining wedge assemblies of the variable geometry clamp to vary the vertical extents of the variable geometry clamp to force mutual frictional engagement of the inner box tube with the outer box tube.
Still another significant aspect and feature of the present invention is the use of installation spacers with a variable clamp assembly which maintains a low and orderly variable clamp assembly profile to aid in the installation of the inner box tube within the outer box tube.
Having thus described embodiments of the present invention and mentioned several significant aspects and features thereof, it is the principal object of the present invention to provide a box tube clamping system.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 illustrates an exploded isometric view of the box tube clamping system, the present invention;
FIG. 2 illustrates an exploded isometric view of the variable geometry clamp;
FIG. 3 illustrates the assembled components of FIG. 2;
FIG. 4 illustrates an assembled box tube clamping system;
FIG. 5 illustrates a cross section view of the box tube clamping system prior to actuation of the variable geometry clamp to urge the inner and outer box tubes into frictional and mutual engagement;
FIG. 6 illustrates a cross section view of the box tube clamping system subsequent to actuation of the variable geometry clamp to urge the inner and outer box tubes into frictional and mutual engagement;
FIG. 7, a first alternate embodiment, is an exploded isometric view of the variable geometry clamp of FIG. 2, including installation spacers;
FIG. 8 illustrates a cross section view of the box tube clamping system showing partial insertion of the inner box tube into the outer box tube and showing the use of installation spacers in the variable geometry clamp; and,
FIG. 9 is a cross section view showing the disengagement of the installation spacers from the variable geometry clamp.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates an exploded isometric view of the box tube clamping system 10 including an outer box tube 12 , an inner box tube 14 which is telescopingly accommodated by the outer box tube 12 , and a variable geometry clamp 16 . The outer box tube 12 , which preferably is open ended, includes upper and lower opposed panels 12 a and 12 b and opposed side panels 12 c and 12 d . An elongated hole 18 is included in the lower panel 12 b . The inner box tube 14 includes upper and lower opposed panels 14 a and 14 b and opposed side panels 14 c and 14 d . The greater and substantially planar portions of variable geometry clamp 16 align to the lower panel 12 b and within the confines of the outer box tube 12 , while the lower vertically oriented portions of the variable geometry clamp 16 extend through and beyond the elongated hole 18 in the lower panel 12 b of the outer box tube 12 . The variable geometry clamp 16 is comprised of a center wedge assembly 22 , adjoining left and right wedge assemblies 24 and 26 , and a bolt 28 and lockwasher 30 , as described later in detail with reference to FIG. 2 .
FIG. 2 illustrates an exploded isometric view of the variable geometry clamp 16 . The left wedge assembly 24 includes a wedge plate 32 having a transversely aligned upwardly facing bevel 32 a opposed to a transversely aligned upwardly facing bevel 32 b . The wedge plate 32 also includes a bottom surface 32 c and a top surface 32 d . A post 34 including a longitudinally oriented body hole 36 is located off center with respect to the wedge plate 32 . One side of the post 34 aligns to the lower edge of the bevel 32 b and extends downwardly from the lower edge of the bevel 32 b and from the bottom surface 32 c of the wedge plate 32 b.
The right wedge assembly 26 includes a wedge plate 38 having a transversely aligned upwardly facing bevel 38 a opposed to a transversely aligned upwardly facing bevel 38 b . The wedge plate 38 also includes a bottom surface 38 c and a top surface 38 d . A post 40 including a longitudinally oriented threaded hole 42 is located off center with respect to the wedge plate 38 . One side of the post 40 aligns to the lower edge of the bevel 38 b and extends downwardly from the lower edge of the bevel 38 b and from the bottom surface 38 c of the wedge plate 38 .
The center wedge assembly 22 includes a wedge plate 44 having a transversely aligned downwardly facing bevel 44 a opposed to a transversely aligned downwardly facing bevel 44 b . The wedge plate 44 also includes a top surface 44 c and a bottom surface 44 d . A post 46 including a longitudinally oriented elongated body hole 48 is located at the center of the wedge plate 44 and extends downwardly from the bottom surface 44 d of the wedge plate 44 . A plurality of gripping ridges 50 a - 50 n are located along and about the top surface 44 c of the wedge plate 44 to facilitate and enhance frictional engagement of the center wedge assembly 22 with the lower panel 14 b of the inner box tube 14 . The post 34 of the left wedge assembly 24 is oriented towards the post 46 of the center wedge assembly 22 and the post 40 of the right wedge assembly 26 is oriented towards the post 46 of the center wedge assembly 22 for best stabilization and alignment of the components of the variable geometry clamp 16 . The bolt 28 extends through body hole 36 of the left wedge assembly 24 and through the elongated body hole 48 of the center wedge assembly 22 to threadingly engage the threaded hole 42 of the right wedge assembly 26 .
FIG. 3 illustrates the assembled components of FIG. 2 . Insertion of the bolt 28 , as previously described, serves to group and align the left wedge 24 assembly, the right wedge 26 assembly and the center wedge assembly 22 . When assembled, the left and right wedge assemblies 24 and 26 are urged into close intimate contact with and about the center wedge assembly 22 with the actuation of the bolt 28 . Accordingly, the upwardly facing bevel 32 b of the left wedge assembly 24 is in intimate contact with the downwardly facing bevel 44 b of the center wedge assembly 22 , and the upwardly facing bevel 38 b of the right wedge assembly 26 is in intimate contact with the downwardly facing bevel 44 a of the center wedge assembly 22 . Rotary actuation of the bolt 28 in the correct direction draws the left wedge assembly 24 and the right wedge assembly 26 towards each other resulting in the forcing of the center wedge assembly 22 vertically as resultant movement during sliding and forced impingement of the intimately engaged bevels 32 b and 44 b and the intimately engaged bevels 38 b and 44 a.
FIG. 4 illustrates an assembled box tube clamping system 10 , the present invention. Illustrated in particular are the posts 34 , 46 and 40 and the bolt 28 extending through the accommodating elongated hole 18 .
Mode of Operation
FIGS. 5 and 6 further depict the invention and best illustrate the mode of operation of the box tube clamping system 10 . FIG. 5 illustrates a cross section view of the box tube clamping system 10 prior to actuation of the variable geometry clamp 16 to urge the inner and outer box tubes 14 and 12 into frictional and mutual engagement. Prior to any engagement of the inner and outer box tubes 14 and 12 , the variable geometry clamp 16 is first placed into the elongated hole 18 located in the lower panel 12 b of the outer box tube 12 , preferably with the bolt 28 rotated appropriately to cause distanced displacement of the left wedge assembly 24 with respect to the right wedge assembly 26 . Such distancing of the left wedge assembly 24 and the right wedge assembly 26 requires that the top surface 32 d of the wedge plate 32 and the top surface 38 d of the wedge plate 38 are higher than the gripping edges 50 a - 50 n extending upwardly from the top surface 44 c of the wedge plate 44 . The inner box tube 14 can then be aligned within the outer box tube 12 at any time after suitable placement of the variable geometry wedge 16 into the elongated hole 18 . The placement of the variable geometry clamp 16 places the bottom surfaces 32 c and 38 c of the left wedge plate 32 and right wedge plate 38 , respectively, in intimate contact with the upper surfaces of the lower panel 12 b at common areas surrounding the elongated hole 18 . The bolt 28 , the lockwasher 30 , and the posts 34 , 40 and 46 extend downwardly though the elongated hole 18 and at a sufficient distance beyond the panel 12 b to await rotation of the bolt 28 for actuation of the variable geometry clamp 16 .
FIG. 6 illustrates a cross section view of the box tube clamping system 10 subsequent to actuation of the variable geometry clamp 16 to urge the inner and outer box tubes 14 and 12 into frictional and mutual engagement. During such actuation, the bolt 28 is rotated in the appropriate direction to draw the left wedge assembly 24 and the right wedge assembly 26 towards each other. As the bolt 28 is rotated, the engagement of the threads of the bolt 28 in intimate engagement with the threads of the threaded hole 42 of the post 40 draws the post 40 along a portion of the elongated hole 18 , thus causing the bottom surface 38 c of the attached wedge plate 38 to slide longitudinally along the lower panel 12 b , as well as along and about a portion of the elongated hole 18 , whereby the right wedge assembly 26 is forcibly repositioned towards the left wedge assembly 24 . An opposing and simultaneous motion occurs with respect to the left wedge assembly 24 . As the bolt 28 is rotated, the engagement of the bolt 28 and lock washer 30 in intimate engagement about the body hole 36 of the post 34 draws the post 34 along a portion of the elongated hole 18 , thus causing the bottom surface 32 c of the attached wedge plate 32 to slide longitudinally along the lower panel 12 b , as well as along and about a portion of the elongated hole 18 , whereby the left wedge assembly 24 is forcibly repositioned towards the right wedge assembly 26 . As previously described, the upwardly facing bevels 32 b and 38 b of the wedge plates 32 and 38 are in intimate contact with the downwardly facing bevels 44 b and 44 a of the wedge plate 44 . As the left wedge assembly 24 and the right wedge assembly 26 advance horizontally towards each other, the center wedge assembly 22 is urged and forcibly advanced upwardly by interaction of the advancing and upwardly facing bevels 32 b and 38 b with the downwardly facing bevels 44 b and 44 a . The elongated hole 48 in the post 46 allows for movement of the post 46 of the center wedge assembly 22 about the bolt 28 . The bolt 28 is rotated until the center wedge assembly 22 ultimately causes intimate forced contact of the gripping edges 50 a - 50 n with the lower panel 14 b and resultant intimate forced planar contact of the upper panel 14 a of the inner box tube 14 with the upper panel 12 a of the outer box tube 12 . Although the use of one variable geometry clamp 16 is described, a plurality of variable geometry clamps 16 could be utilized should additional clamping be desired for the joining of box tubes being of greater length or weight. The joining of box tubes is demonstrated in the invention; however, other tubes or structures could be joined incorporating the teachings of the invention such as, but not limited to, joining dimension lumber to an outer box tube, joining fiber glass railroad crossing arms to an outer box tube, joining an I-beam to an outer box tube, or joining a round inner tube to a rectangular or round shaped tube. Modification of the shape of the wedge plates, such as to provide curved or arced wedge plates or other geometric configurations, shall not be deemed as limiting to the scope of the invention.
First Alternative Embodiment
FIG. 7, a first alternative embodiment, illustrates an exploded isometric view of the variable geometry clamp 16 shown with similarly constructed installation spacers 52 and 54 . Each of the installation spacers 52 and 54 is fashioned preferably of a plastic, such as a polycarbonate available under the registered trademark LEXAN, or of other suitable plastic or other material, and can be utilized to facilitate and promote substantially unrestricted entry of the inner box tube 14 within the outer box tube 12 , as shown in FIG. 8, without significant interference from the variable geometry clamp 16 . The use of the installation spacers 52 and 54 ensures that a low and orderly profile of the variable geometry clamp 16 is maintained during insertion of the inner box tube 14 into the outer box tube 12 . Each of the installation spacers 52 and 54 is U-shaped and each includes a slot 55 formed by an arcuate surface 56 having vertically aligned wall extensions 58 and 60 extending upwardly therefrom. Installation spacer 52 aligns as a spacer between the post 34 of the left wedge assembly 24 and the post 46 of the center wedge assembly 22 and over and about a portion of the bolt 28 which is accommodated by the slot 55 . In a similar fashion, the installation spacer 54 aligns as a spacer between the post 46 of the center wedge assembly 22 and the post 40 of the right wedge assembly 26 and over and about a portion of the bolt 28 which is accommodated by the slot 55 .
FIG. 8 illustrates a cross section view of the box tube clamping system 10 showing partial insertion of the inner box tube 14 within the outer box tube 12 prior to actuation of the variable geometry clamp 16 to urge the inner and outer box tubes 14 and 12 into frictional mutual engagement. Dashed line pairs show the insertional paths 14 e and 14 f of the inner box tube 14 . Prior to any engagement of the inner and outer box tubes 14 and 12 , the variable geometry clamp 16 utilizing the installation spacers 52 and 54 , which maintain a low and orderly variable geometry clamp 16 profile, is first placed into the elongated hole 18 located in the lower panel 12 b of the outer box tube 12 . The installation spacers 52 and 54 are placed as described previously in FIG. 7 between the posts 34 , 46 and 40 and over portions of the bolt 28 with the bolt 28 being rotatingly positioned to cause the alternatingly spaced posts 34 , 46 and 40 and the alternatingly spaced and appropriately dimensioned installation spacers 52 and 54 to draw together until the bolt 28 is prevented from further rotation by the compressed geometry of the posts 34 , 46 and 40 and the interposed installation spacers 52 and 54 . The longitudinal dimensioning or thickness of the installation spacers 52 and 54 is such that upon full tightening of the bolt 28 , the upward travel of the center wedge assembly 22 is limited as the travel of the left wedge assembly 24 and the right wedge assembly 26 is restricted. The inner box tube 14 can be aligned fully within the outer box tube 12 at any time after suitable placement of the variable geometry wedge 16 utilizing installation spacers 52 and 54 into the elongated hole 18 .
With respect to the removal of the installation spacers 52 and 54 , as depicted in FIG. 9, it is to be noted that the vertical dimensions of the installation spacers 52 and 54 are such that spaces, such as the immediately viewable and near space 62 , are located between the upper portions of the wall extensions 58 and 60 and the areas of the lower panel 12 b surrounding the elongated hole 18 . If required, a prying member such as a screwdriver can be inserted into such spaces to pryingly urge the installation spacer 52 from between the post 34 and the post 46 and the installation spacer 54 from between the post 46 and the post 40 in the event that a slightly oversized inner box tube 14 causes resistance to suitable retractive rotation of the bolt 28 .
FIG. 9 illustrates a cross section view of the box tube clamping system 10 where the inner box tube 14 has been fully advanced within the outer box tube 14 and advanced along and past the noninterferring variable geometry clamp 16 . Subsequently, the bolt 28 is then rotatingly actuated (as shown) to relieve the compression along the alternatingly spaced posts 34 , 46 and 40 and the alternatingly spaced installation spacers 52 and 54 prior to actuation of the variable geometry clamp 16 for engagement with the inner box tube 12 . Compressional relief allows the installation spacers 52 and 54 to disengage from frictional engagement between the respective posts 34 , 46 and 40 and to be released from the structure of the variable geometry clamp 16 . The bolt 28 is then actuated to force the center wedge assembly 22 upwardly to engage the inner box tube 14 and thus join the inner box tube 14 with the outer box tube 12 , as previously described.
Various modifications can be made to the present invention without departing from the apparent scope hereof.
BOX TUBE CLAMPING SYSTEM PARTS LIST
10
box tube clamping
system
12
outer box tube
12a
upper panel
12b
lower panel
12c-d
side panels
14
inner box tube
14a
upper panel
14b
lower panel
14c-d
side panels
14e-f
insertional paths
16
variable geometry
clamp
18
elongated hole
22
center wedge
assembly
24
left wedge
assembly
26
right wedge
assembly
28
bolt
30
lock washer
32
wedge plate
32a-b
bevels
32c
bottom surface
32d
top surface
34
post
36
body hole
38
wedge plate
38a-b
bevels
38c
bottom surface
38d
top surface
40
post
42
threaded hole
44
wedge plate
44a-b
bevels
44c
top surface
44d
bottom surface
46
post
48
elongated body
hole
50a-n
gripping ridges
52
installation
spacer
54
installation
spacer
55
slot
56
arcuate surface
58
wall extension
60
wall extension
62
space | A box tube clamping system featuring a variable geometry clamp for secure joining of telescoping box tubes. A variable geometry clamp aligns between an inner and an outer box tube and includes a center wedge plate flanked by adjoining wedge plates which are advanced towards the center wedge plate to force the center wedge plate in an upward direction to force the outer box tube and the inner box tube into forced and secure intimate frictional engagement. Installation spacers are included for use with the variable geometry clamp to provide user friendly accommodation of an inner box tube past and along the variable geometry clamp mounted in one end of the outer box tube. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
Reference is made to commonly assigned copending application Ser. No. 08/705,468 filed Aug. 29, 1996, entitled "APPARATUS AND METHOD FOR PRODUCING PHOTOGRAPHIC PRINTS WITH WRITEON BORDERS" in the names of J. A. Manico, D. L. Patton and P. H. Forest.
FIELD OF THE INVENTION
The invention relates generally to the field of still images having recorded sound associated with the still image. In one aspect, the invention relates to photofinishing apparatus and methods for reproducing a still image with a sound indicium imprinted on the image print to facilitate association of sound playback with the image during viewing of the image print.
BACKGROUND OF THE INVENTION
The ability to associate sound recorded in a camera with still image prints is of great interest to camera users. U.S. Pat. No. 4,905,029 is an example of prior art showing recording of sound on a magnetic strip which is either integrally formed with instant print material or is separable for later attachment to a processed image print. In U.S. Pat. No. 5,313,235, the camera records sound on a separate medium and exposes an image frame identifying bar code onto the film negative. The bar code is subsequently exposed onto the image print during photofinishing. The code serves as a print image identifier which associates the print with a segment recorded in a separate medium. A sensor connected to a separate playback device reads the code on the print and addresses the associated sound segment in the separate medium for sound playback. While of interest, this approach requires that the code be exposed onto the negative. This has the drawback that there is a risk the code will be obscured during masking that occurs during the print finishing process, unless the code is exposed obtrusively well within the image frame area. Also, since the code is in the negative, it will always be printed even if there is a desire not to associate sound with the print. There is therefore a need for a photofinishing process that enables the printing of a sound address code on an image print without relying on optical exposure from the negative.
FIG. 1 illustrates an example of a finished image print 10 with a sound address code printed as a sound icon 12 in the lower left hand corner of the print. It is desirable that the sound icon be presented generally in the same position relative to the print image, i.e. in the lower portion, relative to at least a majority of the viewed images and preferably near a corner. A difficulty of providing sound icons on prints is that images are printed with a variety of different formats, sometimes varying from image to image within a single filmstrip or order. FIG. 2 illustrates developed image prints on a strip of print paper 13, before cutting, where P represents a panoramic picture, C represents a conventional 3×5 format typical of 35 mm film and H represents an expanded width HDTV format. It should be noted that the center to edge distances D p , D c , and D H are different for each print format. Another difficulty of providing prints with a sound icon is that filmstrips may have been exposed in right-hand- or left-hand-load cameras. As shown in FIG. 3 of the present specification, a filmstrip 14 from a left-hand-load camera will present most of its images in an upright orientation when the film is fed in the direction of the arrow into the printer. In contrast, a filmstrip 16 from a right-hand-load camera will present most of its images in an inverted orientation when the film is fed in the same direction. In the familiar manner, such filmstrips are joined by a film splicing label 18 before they are processed; and the label remains with the filmstrips during subsequent printing from the developed negatives. To distinguish between filmstrips from left- and right-hand-load cameras, each label 18 may include a filmstrip or order number 20 and a code 22 to indicate the upright or inverted orientation of the following filmstrip. Such a technique is disclosed in commonly assigned European patent application No. 0 721 149 A2 published Jul. 10, 1996, the contents of which are incorporated by reference into this application. Even if the photofinisher's equipment can determine the different orientations or formats, or both, of such images, a print gate that places the sound icon in a fixed position will cause the icon to appear in a mixture of positions relative to the image, an unacceptable result for most customers.
To most efficiently provide a sound icon on prints made from images of different orientations and formats, it would be desirable to be able to determine the orientation and format of any image and then selectively position a sound icon printer mechanism so that the sound icon on all prints from a filmstrip would be positioned in the same orientation relative to their respective images. That is, all the icons would be along the lower edge in the corner of the film image and, preferably, in a preselected corner of the image.
SUMMARY OF THE INVENTION
It is an object of the invention to make provision for printing of a sound code on image prints in a manner that solves the problems described above. In accordance with one aspect of the invention, therefore, there is provided a method for producing photographic prints with a sound code icon printed thereon, that comprises the steps of intermittently conveying a filmstrip through a film strip gate for exposure of images on the filmstrip to photographic print paper; intermittently conveying a strip of photographic print paper through a print gate, the print gate defining an image print area for exposure to the filmstrip images; positioning a sound code icon printing device over said image print area; and actuating said icon printing device to expose a sound code icon onto said photographic print paper within said image print area in conjunction with exposure of a negative image onto said print paper.
In accordance with another aspect of the invention, photographic printer apparatus is provided that comprises means for intermittently moving filmstrips through a film gate; a print gate forming an image print area, said print gate including at least one sound code icon printer; means for intermittently moving photographic print paper through the print gate; illumination means for exposing each film image onto said print paper through the image print area of said print gate; means for positioning a sound code icon printer over said image print area; and means for actuating said icon printer to expose a sound code icon on the image print in conjunction with exposure of the film image onto said print paper.
In yet another aspect of the invention, a sound code printer is provided for exposing a circular sound code icon onto an image print on photographic print paper, the icon uniquely identifying the print image, wherein the icon comprises first and second circumferential rings each having binary coded segments uniquely identifying the image print. Segments of the first ring indicate frame number of a film image from which the image print is made on the paper and segments of the second ring indicate a number identifying the film strip on which the film image appears.
These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates schematically a photographic print with a sound code icon printed thereon.
FIG. 2 shows a strip of developed print paper illustrating schematically a sequence of image prints having different print aspect ratios (formats).
FIG. 3 illustrates schematically a developed filmstrip which was exposed in a left-hand-loaded camera and a developed filmstrip which was exposed in a right-hand-loaded camera, the filmstrips being joined by a splice label.
FIG. 4 illustrates schematically a photographic printer apparatus having a sound-on-print print gate embodying a feature of the present invention.
FIG. 5 illustrates schematically a side view of a sound-on-print print gate embodying a feature of the present invention.
FIG. 6 illustrates schematically a plan view of the print gate of FIG. 5.
FIG. 7 is a schematic illustration of a sound code icon of the type useful with the present invention.
FIGS. 8-10B are flow charts illustrating various stage of the method of the invention.
FIG. 11 is an illustration of an index print carrying a sound icon printed thereon.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 4 illustrates schematically a photographic printer embodying the invention. A supply reel 24 supports a wound strip made up of spliced, processed filmstrips 26. As the images on a filmstrip are sequentially exposed onto photographic paper, a take up reel 28 is rotated to wind up the spliced strip. Between the reels, a filmstrip print gate 30 flattens and supports each image on the filmstrip below an illumination source 32 as the filmstrip 26 is intermittently moved through the film gate. Light from source 32 passes through the image, through an adjustable iris 33 and through a projection lens system including a fixed lens element 34 and a movable lens element 35. Below the lens system, a supply roll 36 of photographic paper is rotated to provide a continuous strip 38 of paper on which the images are to be exposed. A takeup roll 40 is rotated to wind up the exposed paper. Between the rolls of paper, the paper is intermittently moved through a paper print gate 42 that includes a platen 44 to flatten and support the paper during exposure. To determine proper exposure conditions for each image and, if appropriate, to help detect panoramic or HDTV images or to help determine the orientation of individual images, a conventional electronic scanner 46 may be included. To read information recorded magnetically on the filmstrip, a magnetic read head 48 may be included. Also, to read information recorded optically on the filmstrip, an optical read head 50 may be included. In the conventional manner, a programmable controller 52 is connected to drive systems, not shown, for the filmstrip and paper and to scanner 46 and read heads 48,50. Thus, in the familiar manner, each image is scanned and any associated magnetic or optical codes are read as the image moves to gate 30. The illumination system, iris and lens system are then adjusted as appropriate to expose the image properly onto the photographic paper. To provide sound code icons on the prints in accordance with the invention, a sound-on-print print gate 60 is provided between the illumination source and the print paper. The sound-on-print print gate 60 includes a pair of sound icon printers 64,66 provided along opposite edges of the paper print gate 42 relative to the direction of movement of the paper. As will be seen, one of the sound icon printers is movably positioned in the image print area for exposure of a sound icon in conjunction with exposure of the film image onto the print paper in the image print area of the print gate 60.
Referring now jointly to FIGS. 5 and 6, FIG. 5 illustrates details of the print gate 60 adapted to print sound code icons on a strip of photographic print paper 62. FIG. 6 shows in plan view more details of the print gate 60. Print gate 60 includes first and second sound icon printers 64 and 66. Sound icon printer 64 is shown in the position used for the exposure of normal 3R, 4R and 5R prints where the 3R, 4R and 5R designations refer to different sized prints, namely 3R (4×5 inch; 101.6×127 mm), 4R (4×6 inch; 101.6×152.4 mm) and 5R (5×7 inch; 127×177.8 mm). The sound icon printer 64 is used for printing the sound icon 12 when the print image 68 is oriented normally. A second sound icon printer 66 is used for printing the sound icon 12 when the print image 68 is inverted. Sound icon printers 64 and 66 are mounted on pivotable arms 70 and 72, respectively, for rotation in and out of the image exposure area 74 in the directions shown by arrows 76 and 78. Arms 70,72 are rotated by actuator motors 80 and 82, respectively, which are powered through lines 84 and 86 from a power supply 88. Timing of the actuator motors is controlled by logic and control computer 20 via lines 90 and 92 respectively. Sound icon printer 64 is shown rotated into its printing position and sound icon printer 66 is shown rotated out of the printing position. In addition to being able to be rotated into and out of printing position both sound icon printers 64 and 66 can be moved parallel to the path of the print paper 62. The direction of movement of the print paper is indicated by arrow 94 and the translational movement of the sound icon printer 64 and 66 parallel to the paper path is indicated by arrows 95 and 96, respectively. Sound icon printers 64 and 66 are driven into position along tracks 100 and 102 by motors 104 and 106 powered, respectively, via lines 108 and 110 by power supply 88. The timing and amount of translation is controlled by logic and control computer 20 via control logic lines 112 and 114. Motor 104 turns the threaded lead screw 116 which is mounted to the sound print gate 60 by mounting steps 120 and 122. Threaded lead screw 116 engages sound icon printer 64 through the threaded drive connection step 124. Motor 106 turns the threaded leaded screw 118 which is mounted to the sound print gate 60 by mounting steps 128 and 130. Threaded lead screw 118 engages sound icon printer 66 through the threaded drive connection step 126.
The sound code printer 64 uses an LED print head 132 and sound code printer 66 uses an LED print head 134 to print the sound print icon 12, an example of which is described more detail in connection with FIG. 7. The printing of the code is controlled by logic and control computer 20 through lines 136 and 138 respectively. The LED print heads are powered by power supply 88 through power lines 140 and 142, respectively.
FIG. 7 illustrates an exemplary format useful as the sound icon 12 although it will be appreciated that the invention is not limited to a particular icon format. For example, an icon comprised of a linear bar code may be employed. In the illustration of FIG. 7, the icon 12 is generally composed of concentric rings 150 and 152 formed about an inner circular segment 154. These rings comprise a plurality of segments providing binary coded data uniquely identifying the associated print image. The inner ring 150 comprises a plurality of segments 156, of equal area, that identify the film frame number of the image print. The outer ring 152 comprises a plurality of equal area segments 158 that are used to identify the cartridge identification (CID) number which uniquely identifies the film strip. In the illustrated embodiment, there are seven equal area segments in the inner ring 150 and 12 equal area segments in the outer ring 152. By controlling the LED printer to expose, or not expose, selected segments in the icon, a binary code is produced that represents the appropriate frame number and CID number that uniquely identifies the print image. One radially extending segment 160 is always printed with a fixed, pre-defined alignment pattern. The binary value of any given segment in the inner and outer rings is determined by the angular distance of the segment from the alignment pattern. In the illustrated alignment pattern, a 25% area 162 is printed dark followed by a light 50% area 166 and ending with a dark 25% area 164. This same pattern extends radially across both inner and outer segments 150 and 152. A binary table for the illustrated icon is shown in Table I.
TABLE I______________________________________ ICON SEGMENT. VALUE______________________________________ A 1 B 2 C 4 D 8 E 16 F 32 G 64 H 128 I 256 J 512 K 1024 L 2048______________________________________
The inner circular segment 154 comprises a sound indicator segment which may show a symbol such as musical note 155. This symbol, when present, may be used to indicate that sound exists for the associated print image at the time of print development. Absence of the symbol 155 may be used to indicate that no sound exists at the time of photofinishing. However having the remainder of the code printed on the print allows the owner to record sound later, if desired, and to utilize the number code to uniquely associate the subsequently recorded sound with the image print.
FIGS. 8-10B are flow charts showing the method of operation of a photographic printer embodying the invention. FIG. 8 is a schematic showing the steps in the sound-on-print printer order sort routine. The order enters the sound-on-print printer order sort routine at "X" where the sound-on-print printer order sort routine sorts each order by using information obtained from the order information logic and control computer 20. At step 180, the photofinisher inputs information to the system via computer 20 concerning whether a given original order or a reorder is to have prints with the sound icon recorded thereon ("sound-onprints") and the size of the prints to be produced, i.e. 3R, 4R, or 5R. In the case of reorder prints using the Universal Reorder System (URS) or Kodak Reorder System (KRS), information regarding sound icon on prints may be provided by a computer disk for URS or by a punch code tape attached to the reorder negatives for KRS. If query 180 determines that the printing of the sound icon on prints is not requested, the system proceeds to a normal print routine at step 184. If sound-on-prints is requested, the system proceeds to step 182. At step 182, the order information logic and control computer 20 answers the query as to whether the sound should be printed on each print or only on the index print. If only on the index print, step 183 sets an action flag to cause the index print to be printed with the sound icon and the routine branches at step 184 to normal print routine. If not solely on the index print, step 185 determines if the sound icon is to be printed on the index print (as well custom prints) and if so, step 186 sets an index print sound icon action flag after which the routine proceeds to step 188. If only the sound icon is to be printed solely on the prints, the routine goes directly to step 188. One of the 3R, 4R or 5R print routines as determined at steps 188/190, 192/194 and 196/198. If the print size has not been specified, the system returns at step 199 to step 180.
FIG. 9 shows the print routine for 3R prints, those for 4R and 5R being substantially identical. Instruction for 3R prints is received at step 200 and paper width is checked at step 202. If the incorrect paper is present, a change is made at step 204. If the correct paper is present, the magnification setting of the lens system is checked at step 206. If the magnification is not correct, a change is made at step 208. If the magnification is correct, the status of the paper advance system is checked at step 210. If the advance system is not correct, a change is made at step 212. If the advance system is correct, the print order is checked at step 214 to see if all panoramic prints are requested. If all panoramic prints are requested, the paper advance and magnification are adjusted at step 216. The system then proceeds to a sound-on-print routine at step 218.
FIGS. 10A,10B show the steps in the sound-on-print printer print routine. In FIG. 10A, the sound-on-print order routine enters at point "B". Using information obtained from the order information logic and control computer 20 fed into decision step 230, it is determined if the sound-on-print negative is a panoramic or HDTV print negative. If the sound-on-print negative is a panoramic or HDTV print negative, the routine waits until the correct magnification and printer paper advance are automatically set on the printer at step 232 before proceeding to decision step 234. Using information obtained from the order information logic and control computer 20 fed into decision step 234, it is determined if the sound-on-print order is asking for alternating normal prints (no sound icon) and sound-on-prints from each negative or if sound-on-print order is asking for a sound-on-print on all prints from each negative. The customer, for example, may which to have multiple prints from each negative but have only one or two of the group carry the sound icon. If the sound-on-print order is asking for alternating normal prints and sound-on-prints from each negative, step 236 automatically sets a counter for the number of sound-on-prints desired for each negative before proceeding to decision step 238; otherwise the routine goes directly to decision step 238. Using information obtained from the order information logic and control computer 20 fed into decision step 238, it is determined if the sound-on-print negative is inverted, or if the sound-on-print negative is oriented normally. If normal (not inverted), step 240 causes activation of motor 80 to rotate icon printer 64 into position over the image print area. If inverted, step 242 activates motor 82 to position icon printer 66 over the image print area. Using information obtained from the order information logic and control computer 20 fed into decision step 244, it is determined if the sound-on-print negative is a panoramic negative, or if sound-on-print negative is not a panoramic negative. If the sound-on-print negative is a panoramic negative, the selected icon printer is positioned by step 246 at the extreme of its translation track to place the printer in the corner of the image print. If not a panoramic print, step 248 determines if it is an HDTV print and, if so, step 250 activates the printer motor to position the icon printer at an intermediate position corresponding to the location of the corner of the HDTV print image area. If neither a panoramic nor HDTV print, the icon printer remains at its default position corresponding to the corner of the C print shown in FIG. 3. After the icon printer is properly positioned, the routine proceeds to point "D" for entry into the remainder of the sound-on-print routine.
FIG. 10B shows the remainder of the sound-on-print routine. Using information obtained from the order information logic and control computer 20 fed into decision step 260, it is determined if the sound-on-print order requires the sound icon of the sound-on-print. If the sound icon is required, the routine proceeds to decision step 264. If the sound icon is not required, the sound icon printer is not enabled, step 262, and the routine proceeds to action step 272. If the sound icon is required, then, using information obtained from the order information logic and control computer 20 fed into decision step 264, it is determined if the sound for the sound-on-print order was recorded by the camera. If the sound for the sound-on-print order was recorded by the camera, action step 266 conditions the sound icon printer to include the music note 155 within the center segment 154 of the sound icon 12; otherwise the music note is not enabled, step 268. The sound-on-print routine now proceeds to action step 270 causing the sound icon is to be exposed. At action step 272, the exposure sequence of the print is completed, the paper is advanced, and punched. Step 274 retracts the icon printer and step 276 decrements the counter which is tracking the number prints to carry the sound icon for this negative. At decision step 278, using information obtained from the order information logic and control computer 20, it is determined if the count on the counter set in action step 236 in FIG. 10A is zero. If not, step 280 returns the routine to point "C" of the sound-on-print routine (FIG. 10A) to incorporate the sound icon on the next print. If the count on the counter set in action step 236 is zero, the routine proceeds to action step 282 and the parameters are reset for the next negative. The routine then proceeds to decision step 284 where it is determined if the order is complete and, if not, step 286 returns the routine to the beginning of the sound-on-print routine at point "B" (FIG. 10A). If the order is complete, step 288 returns the routine to point "X" to commence processing of the next film order.
FIG. 11 illustrates a sound-on-print index print 300 which bears a unique identification number ("000001") which appears in eye readable form 310 and in bar coded form 320. The sound-on-print 300 displays all the images 330 in a specific photographic order. Usually there is space on the sound-on-print index print 300 for forty images and the images are identified by their frame numbers 340. The sound icon can be printed in the upper right hand corner in a manner similar to its location on an inverted print and positioning of the icon printer can be selected be an additional decision step during the positioning routine (FIG. 10A) in the same manner as positioning for the inverted image print.
The invention has been described with reference to a preferred embodiment. However, it will be appreciated that variations and modifications can be effected by a person of ordinary skill in the art without departing from the scope of the invention.
PARTS LIST 88 power supply
10 photographic print 90,92 actuator signal control lines
12 sound code icon 94 print paper travel direction arrow
13 developed strip of print paper 95,96 icon printer translation arrows
14 filmstrip (left hand load) 40 100,102 icon printer translation tracks
16 filmstrip (right hand load) 104,106 icon printer translation actuator
18 film splicing label motors
20 film order ID number 108,110 motor power lines
22 orientation code number 112,124 control logic lines
24 film supply reel 45 116,118 threaded lead screws
26 spliced, processed filmstrips 120,122,128,130 mounting steps
28 take up reel 124,126 threaded drive connection steps
30 filmstrip print gate 132,134 LED print heads
32 illumination source 136,138 LED print head control lines
33 adjustable iris 50 140,142 LED print head power lines
34 fixed lens element 150,152,154
35 movable lens element 155 musical note symbol
36 print paper supply roll 156 frame number code segments
38 strip of photographic print paper 158 CID number code segments
40 paper take up roll 55 160 alignment segment
42 paper print gate 162,164 dark sections of alignment
44 platen segment
46 scanner
48 magnetic read head
50 optical read head
52 programmable print controller
60 sound-on-print print gate
62 photographic print paper
64,66 sound icon printers
68 print image
70,72 icon printer mounting arms
74 image exposure area
76,78 rotation directions
80,82 arm actuator motors
84,86 motor poser lines | Apparatus and method for printing sound code icons on photographic prints produced from filmstrips having images with varying orientation, size and or format. A sound-on-print print gate includes a pair of selectable LED icon printers for printing a binary coded sound icon on either edge of the photographic print depending on normal or inverted image orientation. The icon printers are mounted for translational movement lengthwise of the print paper, the positioning being determined by the format of the print: panoramic, normal or HDTV aspect ratios. A computer controlled system is disclosed which determines the orientation, size and format and positions the icon printers in response thereto at the print gate. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to an automatic door operator for use in swing doors.
FIG. 1 shows a typical well-known automatic swing door, in which a swing door 1 which rotates about a vertical axis is automatically opened and then closed by activating an accessing body sensing device such as mat switch 3. A signal from the mat switch 3 is transmitted through a cable 5 to a door operator 7 mounted on a header or transam 9 of a jamb or door supporting frame 8. In the operator 7, according to the signal supplied, an electric motor provided therein is energized. When the motor is energized a door swinging link mechanism 11 acting as an opening and closing means, connected through power transmission means to the electric motor, is actuated to open and close the door 1. However, when the power supply is stopped in this type of automatic swing door, the door must be opened and closed by hand. For example, in the case where an automatic swing door is also used as a fire or smoke door, the door is often left open when the power supply is stopped due to fire, since those escaping a fire usually do not stop to close the door. Thus, automatic swing doors in the prior art do not adequately perform fireproof and smokeproof functions when needed.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an automatic door operator for swing doors in which when a failure of the power supply occurs the door is automatically and completely closed, whereby the automatic door operator adequately serves as a door operator for fire or smoke doors.
This and other objects in view, the present invention provides an automatic door operator, for a swing door supported by a door supporting frame to swing about a vertical axis, comprising: means, adapted to be attached to the swing door, for opening and closing the swing door; means, connected to the opening and closing means, for driving the opening and closing means to open the swing door, the driving means including a prime mover for driving the opening and closing means; means for electrically controlling the driving means to swing the swing door; means for sensing a body accessing the swing door and thereby providing a signal to open the door to the controlling means; and a door closer connected to the door opening and closing means, the door closer including resilient means for storing part of the mechanical energy provided by the driving means in opening the swing door and for exerting a driving force on the door opening and closing means by using the stored mechanical energy to close the door.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims which particularly point out and distinctly define the subject matter which is regarded as the invention, it is believed the invention will be more clearly understood when considering the following detailed description and the accompanying drawings in which:
FIG. 1 is a perspective view illustrating the prior art automatic swing door;
FIG. 2 is a perspective view illustrating one embodiment of the present invention;
FIG. 3 is a lengthwise vertical section of the automatic door operator in FIG. 2;
FIG. 4 is a plan view partly cut away and showing a door closer used in the automatic door operator in FIG. 2;
FIG. 5 is a time chart showing one aspect of the operation of an automatic swing door using the door operator in FIG. 2;
FIG. 6 is a time chart showing another aspect of the operation of an automatic swing door using the door operator in FIG. 2;
FIG. 7 is a time chart showing a still another aspect of the operation of an automatic swing door using the door operator in FIG. 2;
FIG. 8 is a time chart showing a further aspect of the operation of an automatic swing door using the door operator in FIG. 2;
FIG. 9 is a perspective view illustrating a modified form of the automatic door operator in FIG. 2;
FIG. 10 is a lengthwise vertical section of the automatic door operator in FIG. 9;
FIG. 11 is a perspective view illustrating a further modified form of the automatic door operator in FIG. 2;
FIG. 12 is a lengthwise vertical section of the automatic door operator in FIG. 11;
FIG. 13 is a block diagram of the automatic door operator in FIGS. 2 and 11; and
FIG. 14 is a block diagram of the automatic door operator in FIG. 9;
FIG. 15 is a front view of a modified form of the detector in FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 2 to 4, there is illustrated one embodiment of the present invention in which a reference numeral 13 designates a support plate made of metal or the like which is fixedly attached to the header 9 of the door supporting frame as shown in FIG. 1. Mounted on the support plate 13 are a drive unit 15 for driving the door swinging link mechanism 11, and a control unit 17 for electrically controlling the drive unit 15 to open the swing door 1. The drive unit 15 includes an electric motor 19 and a speed reducer 21 of a gear train, a first gear member 23 of which meshes with a gear 25 integrally formed with the lower end of a rotational shaft 27 of the electric motor 19. A shaft 29 of a last gear member 31 of the speed reducer 21 constitutes a driving shaft which is connected in a well known manner for transmitting a rotational force to a mechanism for opening and closing the door 1 such as door swinging link mechanism 11 shown in FIG. 1. On the upper end of the rotational shaft 27 of the electric motor 19, there is disposed a solenoid brake 33 so as to surround the rotational shaft 27. The solenoid brake 33 applies a braking force on the rotational shaft 27 when it is energized, thereby preventing the rotation of the drive shaft 27. Mounted on the upper end of the drive shaft 29 is a timing gear 35, which transmits rotation through another timing gear 37 to a door open angle detector 39 for detecting an open angle degree of the door 1 or a horizontal angle formed between the door 1 and door supporting frame 8. This detector 39 includes a generally channel shaped support member 41 mounted on the support plate 13, a rotational shaft 43, vertically and rotatably supported by upper and lower flanges of the support member 41, which carries the timing gear 37 on its upper end, a program cam 45 mounted around the rotational shaft 43, and a photosensor 47 attached to a web of the support member 41. The photosensor 47 receives the periphery of the program cam 45 into a slit formed therein to thereby detect cut-out portions formed in the cam 45 as it turns, so that the photosensor 47 provides a signal of a predetermined door open angle to a control unit 19 which will be described hereinafter, whereby a predetermined rotation angle of the drive shaft 29, i.e., a predetermined door open angle is detected. On the support plate 13, there is further mounted a door closer 51 of a type used in swing doors, which as seen from FIG. 4 comprises a hollow cylinder 53 horizontally attached to the support plate 13 and containing a viscous oil 69, a piston 55 slidably and sealingly fitted into the cylinder 53, a compression coil spring 57 one end of which is attached to a front end 59 of the piston 55 and the other end of which is attached to the inner wall of one of closed ends 61, and a pinion 63 fixedly mounted on the upper portion of the drive shaft 29 which sealingly passes through the cylinder 53 and further passes through an elongate opening 65 formed through the piston to extend axially. The pinion 63 engages with a rack 67 integrally formed with one side wall of the opening 65 to extend axially. When the swing door 1 is to be opened, the drive shaft 29 is rotated to move the piston 55 against the coil spring 57 in a direction indicated by the arrow in FIG. 4 via the rack and pinion engagement, in which event part of viscous oil 69 contained in a coil receiving space 71 of the cylinder 53 flows through an axial passage 73 formed through the front end 59 of the piston 55 into the opening 65 and then it flows through two passages, that is, a narrow axial passage 77 formed through a rear end 75 of the piston 55 and a check valve 79 provided in the rear end 75 into a rear space 81 defined between the rear end 75 and the rear closed end 83 of the cylinder 53. As a result, the compression spring 57 is caused to compress, and thereby store mechanical energy for subsequent usage. In closing the swing door 1, the spring 57 is released and urges the piston 55 to move toward the rear closed end 83 of the cylinder, so that the drive shaft 29 is rotated via the rack and pinion engagement in a direction to close the swing door 1. In this event, the check valve 79 is closed, and hence part of viscous oil 69 within the space 81 flows through only the narrow passage 77 into an opening 65 and then through the passage 73 into the space 71. Since the check valve 79 is closed in closing the door 1, the door can be automatically closed at an optimum speed by providing the narrow passage 77 with an appropriate cross-sectional area. The control unit 17 includes a conventional electrical control devices including timers. The unit 17 stores data as to door opening speed, door opening period and the like and controls the electric motor 19 and the brake 33 according to an open control signal from the mat switch 3 and an open angle signal from the door open angle detector 39 as will be described below.
Referring now to FIGS. 5 and 13, the operation of the automatic door operator will be described with respect to one aspect thereof. Assuming that the swing door 1 is in a closed condition as shown in GRAPH 1, the compression spring 57 is preloaded to apply a force closing the swing door 1. The mat switch 3 is activated as shown in GRAPH 2 when a person steps thereon, which then provides a door open control signal to the control unit 17, which causes the electric motor 19 to be connected to a power source (not shown) to thereby energize it. (GRAPH 3) Thus, the drive unit 15 is actuated to rotate the drive shaft 29 in a direction to open the swing door 1. In this case, the rotation speed of the electric motor 19 is set high, so that the swing door 1 is turned at a relatively high speed about its vertical hinged axis in an open direction. When the swing door 1 is opened to a predetermined angle relative to the header 9 of the door supporting frame, e.g. 70° for a door with a maximum open angle of 90°, the photosensor 47 detects the predetermined angle by detecting a first cut-out portion of the program cam (GRAPH 4 in FIG. 5) corresponding to the predetermined open angle of the swing door 1, and supplies a first open angle signal to the control unit 17 which in turn reduces the rotation speed of the electric motor 19 (GRAPH 3), so that the opening speed of the swing door 1 becomes lower and it slowly opens from the predetermined angle position slightly before the door 1 is completely opened. In the latter event, the photosensor 47 detects the open angle of the door 1 at this stage by sensing a second cut-out portion (not shown) of the program cam 45 and provides a second open angle signal to the control unit 17, so that the electric motor 19 is deenergized and simultaneously solenoid brake 33 is energized with the result that a braking force is applied to the rotational shaft 27 (GRAPH 5). As a result, the rotation of the drive shaft is immediately stopped and thus the swing door 1 is held in a completely open condition, e.g., 90°-open condition by the solenoid brake 33 for a predetermined time interval which datum is previously inputted into the control unit 17. During the above-described door opening stroke, the compression force applied to the compression spring 57 is gradually increased as the swing door 1 opens (GRAPH 7), and becomes maximum when the door 1 is completely opened.
After the predetermined time interval during which the swing door 1 is completely opened, the control unit 17 deenergizes the solenoid brake 33 to thereby release the rotational shaft (GRAPH 6), so that the drive shaft 29 is caused to be rotated in a direction to close the door 1 by a counterforce exerted by the compression spring 57 via the rack and pinion engagement. (GRAPH 7) Thus, the swing door 1 is closed at a speed defined by the door closer 51.
FIG. 6 illustrates a second operation of the automatic door operator, which differs from the first aspect of operation above described in that during the closing of the door a small force for closing the swing door 1 is applied to the drive shaft 29 by reversing slowly the electric motor 19 in addition to the counterforce exerted by the compression spring 57 on the drive shaft 29, ensuring the door 1 to be positively closed. (GRAPH 3) This reversal of the electric motor 19 is controlled by the control unit 17 in such a manner that the control unit 17 supplies the electric motor 19 with a current to rotate slowly that motor in a reverse direction relative to a direction to open the door 1. Although the driving force exerted by the door closer 51 on the drive shaft 29 becomes smaller at low temperatures due to an increase in viscosity of the viscous oil contained in the cylinder 83, in this second operation the door 1 is positively closed by the additional force exerted by the electric motor 19.
Referring to FIG. 7 a third operation of the first embodiment of the present invention will be described. This third operation differs from the first operation already described in that when the swing door 1 is closed, the photosensor 47 detects this state by sensing a third cut-out portion (not shown) formed in the program cam 45 and provides the control unit 17 with a signal to energize the solenoid brake 33, so that brake prevents the drive shaft from being rotated to thereby prevent the swing door 1 from being opened by wind and the like.
FIG. 8 illustrates a fourth operation of the first embodiment, which differs from the second operation, described with reference to FIG. 6, in that when the swing door 1 is closed, the solenoid brake 33 is energized to prevent the rotation of the drive shaft 29 as in the third operation description in FIG. 7.
Although in the above embodiment, the rotational shaft 29 of the last gear member 31 passes through cylinder 53 of door closer 51, the shaft of pinion 63 and the rotational shaft of the last gear member 31 may be joined by mortise and tenon formed in opposed ends of those shafts.
FIGS. 9 and 10 illustrate a modified form of the embodiment shown in FIGS. 2 to 5. The modification is that the solenoid brake 33 is disposed to surround a rotational shaft 87 of a second gear member 85 of the speed reducer 21, thereby applying a braking force to the rotational shaft 87 when energized. This modified form is preferable in the case where the height of the door operator needs to be reduced. The block diagram of this modification is shown in FIG. 14.
In FIGS. 11 to 12, the solenoid brake 33 is disposed to surround a rotation shaft 89 of a gear member 90 which engages with the gear 25 of the rotation shaft 27 of the electric motor, the rotation shaft 89 of the gear member 90 being rotatably supported by the support plate 13 and the cover 93 of the speed reducer 21. The block diagram of this modification is shown in FIG. 13. This modified form is preferable where the height of the speed reducer 21 needs to be minimum.
FIG. 15 illustrates a modified form of the detector in FIG. 2, in which in place of timing gear 35 a program cam plate 45 is mounted on the upper end of the rotational shaft 29, and a photosensor 47 including a photoemitting element and photoreceiving element (not shown) is placed at one side of the cylinder 53 of the door closer 51 below the program cam 45. The photoemitting element emits light and the photoreceiving element receives light reflected by the program cam 45. The cut-out portions of the cam do not reflect light emitted from the photoemitting element, and thus the photosensor 47 detects the cut-out portions by not receiving any reflected light. | An automatic door operator for a swing door supported by a door supporting frame to swing about a vertical axis. The automatic door operator includes a mechanism for opening and closing the swing door, a drive for driving the door opening and closing mechanism to open the swing door, the drive including a prime mover for driving the door opening and closing mechanism, a door closer including a resilient device for storing part of mechanical energy provided by the drive in opening the swing door and for exerting driving force on the door opening and closing means by using the stored mechanical energy to close the door, a unit for electrically controlling the drive to swing the swing door, and a sensor for sensing a body accessing the door and thereby providing an electric signal to open the door to the controlling unit. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
This application claims the benefit of International Application No. PCT/KR2014/006883, filed on Jul. 28, 2014, based on Korean Patent Application No. 10-2013-0088722, filed Jul. 26, 2013 and Korean Patent Application No. 10-2014-0019203, filed Feb. 19, 2014, the disclosures of which are hereby incorporated by reference herein in their entirety.
BACKGROUND
1. Technical Field
The present invention relates generally to a humidifier.
2. Description of the Related Art
A humidifier is a device for atomizing water and spraying the atomized water into the air to create a pleasant environment and a comfortable humidity for human health. The humidifier is also often used in order to relieve respiratory diseases caused by dry air.
Generally, ultrasonic humidifiers are widely used, and a conventional ultrasonic humidifier comprises, a water reservoir for storing water and a humidifier body which accommodates the water reservoir and includes an electric circuit. On a predetermined position of humidifier body is provided with a ultrasonic vibrator. Accordingly, when the water stored inside the reservoir is supplied on the ultrasonic vibrator, the ultrasonic vibrator atomizes the water to form a mist, and the mist is sprayed outside the humidifier.
After protracted use of the conventional ultrasonic humidifier, a bacteria or a mold and the like grow in the water reservoir, ultrasonic vibrator, etc., which causes the spraying of mist contaminated with the bacteria or mold. The only resolution for this problem is a frequent cleaning or sterilization of the water reservoir, ultrasonic vibrator, etc. However, the reservoir of the conventional ultrasonic humidifier has a shape to help accommodate the reservoir in the humidifier body (for example, a tank having only a small hole in the lower portion of the tank for water supply and so on). Therefore, there are several locations which are difficult for manual cleaning with hands. In addition, in the conventional ultrasonic humidifier, the ultrasonic vibrator is mostly coupled to the humidifier bed including an electric circuit, which makes it difficult to clean or sterilize.
In order to solve the specific problem associated with cleaning due to these factors, an ultrasonic humidifier having the ultrasonic vibrator disposed on the bottom surface of the reservoir instead of the humidifier body was developed and used. But, such an ultrasonic humidifier has a disadvantage in that only a small amount of water can be contained in the water reservoir at any time to allow placement of the ultrasonic vibrator close to the surface of the water for the ultrasonic humidifier to sufficiently atomize the water easily.
SUMMARY
It is an object of the present invention to solve the above-described problems of the conventional arts as a whole.
It is another object of the present invention to provide a humidifier easily cleanable by a user.
It is yet another object of the present invention to provide a humidifier capable of easily sterilizing all the parts that are in contact with water.
It is yet another object of the present invention to provide a humidifier capable of easily separating and sterilizing the parts that are in contact with water.
It is yet another object of the present invention to provide a humidifier with a low manufacturing cost while achieving all of the above objects.
The representative configuration of the present invention to achieve the above objects is as follows.
According to an aspect of the present invention, there is provided a humidifier comprising: a main body including a water reservoir for storing water; an upper body disposed above the water reservoir for covering the water reservoir; and a vibration unit including a vibrator for atomizing the water in the water reservoir, wherein the upper body includes a first lunge part for hinge-coupling with the main body and a second hinge part for hinge-coupling with the vibration unit, the upper body is capable of being lifted from the main body using the first hinge part as a shaft, the vibration unit is capable of rotatably moving in the water using the second hinge part as a shaft, and the vibration unit further includes a vibrator receiving unit for the vibrator.
In addition, other configurations may be provided according to the technical idea of the present invention.
According to the present invention, there is provided a humidifier which can be easily cleaned and sterilized by a user.
According to the present invention, there is provided a humidifier in which the parts contacted with water can be easily separated and sterilized.
Also, according to the present invention, there is provided a humidifier with a low manufacturing cost while achieving all of the above objects.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an overall configuration of a humidifier according to an embodiment of the present invention.
FIG. 2 is a schematic diagram showing a coupling state of the upper body and the vibration unit according to an embodiment of the present invention.
FIG. 3 shows a lower part of the vibration unit according to an embodiment of the present invention.
FIG. 4 shows a location of the vibration unit when containing a small amount of in water in the water reservoir.
FIG. 5 shows a location of the vibration unit when containing a large amount of water in the water reservoir.
FIG. 6 is a diagram showing a state where the upper body is lifted up from the main body according to an embodiment of the present invention.
FIG. 7 is a reference diagram regarding a situation where the water reservoir, the lower part of the vibration unit and the separating plate are being sterilized.
DETAILED DESCRIPTION
The following detailed description of the present invention is made with reference to accompanying drawings illustrating specific embodiments of the present invention. These embodiments are described in detail to the extent that it is sufficient for a person skilled in the art to practice the present invention. Although embodiments of the present invention are different from each other, it should be understood that these are not necessarily exclusive to each other. For example, specific shapes, structures and characteristics as described herein can be practiced by modifying one embodiment to another without departing from the spirit and scope of the present invention. Further, it is to be understood that locations and configurations of the individual components of the embodiments can be modified without departing from the spirit and scope of the present invention. Accordingly, the following detailed description is intended to be non-limitative, and the scope of the present invention should be taken to encompass the scope of the appended claims and their equivalents. Similar reference numerals in the drawings represent the same or similar components in various aspects.
In the following, to allow those skilled in the art to easily practice the present invention, several preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Preferred Embodiments of the Present Invention
FIG. 1 shows an overall configuration of a humidifier according to an embodiment of the present invention. Referring to FIG. 1 , a humidifier 10 comprises an upper body 100 , a main body 200 and a vibration unit 300 .
According to an embodiment of the present invention, the upper body 100 may include a prescribed electric circuit (not shown) for the humidifier therein, and may further include a fan 110 , a first hinge part 120 , a second hinge part 130 and a separating plate 140 . The upper body 100 can be disposed over a water reservoir 210 of the main body 200 to be described later, if desired, thereby covering it.
The electric circuit of the upper body 100 may be used to start or stop the vibration of a vibrator in the vibration unit 300 to atomize water (W) in the water reservoir 210 . Also, the electric circuit may control the fan 110 to rotate as well when the vibrator is vibrating. The control state of the electric circuit can be determined by an operation state of a switch (not shown) attachable to the upper body 100 , main body 200 and so on. The other structure of the electric circuit may be similar to that of the electric circuit of the conventional ultrasonic humidifier. In the meantime, it may be preferable that the electric circuit is included in the upper body 100 ; however, it can be included in the main body 200 , if needed.
The fan 110 can rotate to intake external air into the water reservoir 210 and spray it to the outside of the water reservoir 210 (i.e. the outside of the humidifier 10 ) while including a mist generated in the water reservoir 210 , in addition, a filter not shown) associated with the fan 110 can be disposed. The filter can purify the external air provided into the water reservoir 210 . Meanwhile, the fan 110 may be preferably included in the upper body 100 ; however, it can be included in the main body 200 , if needed.
The first hinge part 120 may be a component for hinge-coupling the upper body 100 and the main body 200 . Accordingly, a user can lift up the upper body 100 from the main body 200 using the first hinge part 120 as a shaft. If the upper body 100 is lifted up from the main body 200 , the vibration unit 300 , which may be directly coupled to the upper body 100 , can be lifted up together with the upper body 100 as it will be described in detail later. Such a structure allows a user to easily take out the water reservoir 210 from the main body 200 without separating the vibration unit 300 .
The second hinge part 130 may be a component for hinge-coupling the upper body 100 and the vibration unit 300 . Accordingly, the vibration unit 300 can move upward or downward while rotating in the water in the water reservoir 210 using the second hinge part 130 as a shaft according to the water level. The movement of the vibration unit 300 will later be described in more detail.
A variable resistance (not shown) can be included in the second hinge part 130 . The variable resistance may be configured to vary its resistance in accordance with the angle of the vibration unit 300 at the second hinge part 130 . Accordingly, the gradient of the vibration unit 300 or the height of the vibrator ( 312 in FIG. 3 ) in the vibration unit 300 in the water reservoir 210 (which approximates the water level in the water reservoir 210 ) can be calculated based on the resistance value of the variable resistance, and the electric circuit may inform the user of the timing of the water replenishment with reference to it. This information may be especially useful when the main body 200 or the water reservoir 210 is made of an opaque material. The case in which the variable resistance is used to check the water level is illustrated herein, but the present invention is not limited thereto. It is possible to also use a water level sensor of the vibration unit 300 or the like as will be described later.
The separating plate 140 serves as a bottom plate of the upper body 100 to cover the electric circuit in the upper body 100 and protect it from the mist generated from the water in reservoir 210 . The separating plate 140 is exposed to the mist at any time, it should be cleaned/sterilized frequently. Accordingly, it is preferable that the separating plate 140 is configured to be separable from the upper body 100 so that it is cleaned or sterilized separately. Also, the separating plate 140 is preferably made of a heat-resistant material such as metal or glass (for example, stainless steel) which can facilitate cleaning or sterilization.
According to an embodiment of the present invention, the main body 200 is the main portion of the humidifier 10 , which may include the water reservoir 210 for storing water therein and for providing a space required for the stored water to become a mist by the vibrator. The water reservoir 210 has a shape in which the upper part thereof is wide and open to make it easy to clean and does not have electrical components which would not allow any contact with the water. So, the user can wash the water reservoir 210 everywhere here and even boil water with it. In this case, the water reservoir 210 can be separated with and taken out from the main body 200 , if needed. On one side of the water reservoir 210 , a mist outlet 211 may be formed, which discharges the mist in the water reservoir 210 to the outside. The user can fill the water reservoir 210 with water and heat the water reservoir 210 to boil the water in order to sterilize the water reservoir 210 . To this end, the water reservoir 210 is preferably made of a heat-resistant material such as metal or glass (for example, stainless steel) which can facilitate cleaning or sterilization.
On the other hand, a heat generation unit (not shown) may be further included under the water reservoir 210 to directly boil the water in the water reservoir 210 . The heat generation unit is made of coils and the like and generates heat when supplied with electricity to heat the water in the water reservoir 210 . The electric circuit can cooperate with a separate switch (not shown) for an operation of the heat generation unit. But, in the case where the water reservoir 210 can be separated from the main body 200 and handled separately, the user can sterilize the water reservoir 210 by simply boiling the water filled inside the water reservoir 210 using a household burner and the like. FIG. 7 is a reference diagram illustrating such a situation. As shown in FIG. 7 , the water reservoir 210 can be sterilized together with the separating plate 140 and the lower part 310 of the vibration unit 300 , which will be described later.
According to an embodiment of the present invention, the vibration unit 300 is disposed for the water stored in the water reservoir 210 and performs a function of creating an oscillation in the water to atomize it. The vibration unit 300 may include a lower part 310 and an upper part 320 . The lower part 310 can include or accommodate the vibrator ( 312 of FIG. 3 ) for vibrating the water, and the upper part 320 is coupled to the second hinge part 130 to suspend the vibration unit 300 to float on the water as a whole while supporting the lower part 310 . Meanwhile, the vibration unit 300 , especially the lower part 310 , may further include a water level sensor (not shown) to inform the user about whether the water is required to be replenished by detecting water at a predetermined location. The water level sensor can provide a prescribed electric signal to the above-described electric circuit to perform a function of start and stop the vibration of the vibrator 312 . That is, a control function that starts the vibration of the vibrator 312 if water is detected and stops the vibration of the vibrator 312 if water is not detected may be performed.
In the following, a coupling state of the upper body 100 and the upper part 320 of the vibration unit 300 is described referring to FIGS. 1 and 2 . In FIG. 1 , the arrow indicates a flowing route of the external air incoming via the fan 110 . FIG. 2 is a schematic diagram showing a coupling state of the upper body and the upper part of the vibration unit according to an embodiment of the present invention.
As shown, the upper part 320 of the vibration, unit 300 can be coupled to the predetermined position of the upper body 110 through the intermediation of the second hinge part 130 . The position is preferably on the incoming route of the external air indicated by the arrow. While it is important for the vibration unit 300 to be hinge-coupled to the upper body 100 in the present invention, the hinge-coupling part of the second hinge part 130 and so on are the parts in which cleaning or sterilization is relatively difficult compared to the part of the separating plate 140 of the upper body 100 . Accordingly, it is preferable to locate it on the incoming route of the external air for the incoming external air to block the approach of the mist to the second hinge part 130 and so on in some degree.
In the same context, as shown in FIG. 2 , it is preferable that the vibration unit 300 has a structure that the protrusion 327 of the upper part 320 thereof is inserted to the groove 317 of the lower part 310 thereof to be combined with each other. Such a configuration helps the user clean the upper part 320 of the vibration unit 300 which is difficult to separate and sterilize by minimizing the indented portions. In the meantime, it is preferable that H 1 or H 2 part of the upper part 320 as shown is sufficiently and constantly apart from the water in the water reservoir 210 by the support of the second hinge part 130 .
On the other hand, by hinge-coupling the vibration unit 300 to the upper body 100 through the intermediation of the second hinge part 130 , and preventing the second hinge part 130 from being dropped down under the vibration unit 300 , due to the upward directional torque in the vibration unit 300 resulting from the auxiliary operation of the hinge or the frictional force at the hinge, the size of the portion of the vibration unit 300 which is submerged in the water (for example, a vibrator receiving unit ( 311 of FIG. 3 ) of the vibration unit 300 which will be described later) can kept as small as possible.
Now, the lower part 310 of the vibration unit 300 is described referring to FIG. 3 . FIG. 3 shows the lower part of the vibration unit according to an embodiment of the present invention.
As shown, the lower part 310 may include a vibrator receiving unit 311 and a vibrator 312 on one side thereof. The vibrator receiving unit 311 may be for a temporary or non-temporary placement of the vibrator 312 , or it can be combined with the vibrator 312 . The vibrator receiving unit 311 may have a structure (for example, a structure that is hollow inside) or a material (for example, a material having a lower density than water) with buoyancy in water. On the other hand, the vibrator 312 can be any one of the types of conventional ultrasound vibrators. The vibrator 312 may start or stop the vibration in accordance with the electric signal received from the electric circuit of the upper body 100 through the wiring (not shown) inside the lower part 310 and the upper part 320 .
The lower part 310 may include at least one terminal 315 on the other side thereof. And, an electrical connection means (not shown) corresponding to the terminal 315 may be formed at a portion of the upper part 320 coupled to the lower part 310 . The terminal 315 or the electrical connection means may be connected to the wiring (not shown) inside the lower part 310 and the upper part 320 as described above.
Furthermore, in order to make the lower part 310 and the upper part 320 detachable from each other, the lower part 310 and the upper part ( 320 ) may include materials with magnetic force for the coupling portion with each other, or include a coupling structure by the frictional force such as protrusions and grooves.
The lower part 310 of the vibration unit 300 can be boiled in water in the same manner as the separating plate 140 and the like, if well packaged, due to the simple electrical structure.
Importantly, the vibrator receiving unit 311 can be formed to be bent from the bottom part 310 to the position where the vibration unit 300 is coupled to the upper body 100 (that is, the position of the second hinge part 130 ), as shown. This configuration is very advantageous for preventing the vibrator 312 from exposure to the water during the flotation of the vibration unit 300 due to the buoyancy when containing a large amount of water in the water reservoir 210 (the vibrator 312 should be submerged in the water while it is vibrating and it is preferable that the vibrator 312 is submerged in the water even while it is not vibrating).
FIG. 4 shows a location of the vibration unit when containing a small amount of water in the water reservoir, and FIG. 5 shows a location of the vibration unit when containing a large amount of water in the water reservoir.
As shown in FIGS. 4 and 5 , in either case that a small or large amount of water is contained in the water reservoir 210 , due to the specific structure of the lower part 310 of the vibration unit 300 according to the present invention, the vibrator receiving unit 311 is disposed under the water surface and the vibrator 312 can atomize water.
FIG. 6 is a diagram showing a state where the upper body is lifted up from the main body in accordance with an embodiment of the present invention.
When a user lifts up the upper body 100 from the main body 200 , the vibration unit 300 coupled to the tipper body 100 is lifted from the main body 200 as well. Accordingly, when the user supplies the water reservoir 210 with water or cleans or sterilizes the water reservoir 210 , the user does not need to separate the vibration unit 300 . Furthermore, the above characteristics serve the convenience of separating the water reservoir 210 easily from the main body 200 in the direction of the arrow and handling it comfortably.
While there has been described herein the present invention with reference to the specific components, embodiments, and drawings, it will be appreciated by those skilled in the art that they are only intended to aid the overall understanding of the present invention, not to limit the present invention to those embodiments, and that various changes and modifications may be made to the invention in view of the above description.
Accordingly, the idea of the present invention should not be limited to the embodiments described above, and it is intended that the present invention encompass the appended claims and the equivalents and modifications thereof as well. | The present invention relates to a humidifier. According to an aspect of the present invention, there is provided a humidifier comprising: a main body including a water reservoir for storing water; an upper body disposed above the water reservoir for covering the water reservoir; and a vibration unit including a vibrator for atomizing the water in the water reservoir, wherein the upper body includes a first hinge part for hinge-coupling with the main body and a second hinge part for hinge-coupling with the vibration unit, the upper body is capable of being lifted from the main body using the first hinge part as a shaft, the vibration unit is capable of rotatably moving in the water using the second hinge part as a shaft, and the vibration unit further includes a vibrator receiving unit for the vibrator. | 5 |
[0001] This application is a continuation of U.S. patent application Ser. No. 12/472,982, filed on May 27, 2009, which claims priority from U.S. Application No. 61/056,329, filed on May 27, 2008, the entire contents of which are incorporated herein by reference.
FIELD OF TECHNOLOGY
[0002] The invention relates in general to autonomous control systems of aircraft, and, more particularly, to multi-aircraft lifting control systems.
DESCRIPTION OF THE RELATED ART
[0003] Aircraft, for example helicopters and airships, that are able to perform unique maneuvers, such as taking off and landing vertically or hovering in one area, have many industrial and commercial applications; they are used as air ambulances, aerial cranes, and military vehicles. These aircraft are also used to transport heavy payloads to locations that are difficult or impossible to reach by ground transportation and other aircraft. The lifting capacity of an individual aircraft approaches limitations asymptotically because lifting a heavier payload requires stronger support mechanisms, larger engines, more fuel, and a larger aircraft overall. The aircraft's weight therefore increases in proportion to the weight that it is to lift. Further, constructing, maintaining and storing large aircraft becomes difficult because of size, for example in extremely large airships. Despite improving load capacities, there is still an ongoing demand to transport much greater loads in both the commercial and military sectors.
[0004] One way to transport greater loads is through the coordinated flight of multiple aircraft. In other words, multiple pilots can fly in formation to carry a common payload. This is done by tethering the payload to multiple helicopters using cables. By way of background, helicopters, for example, have rotating blades that provide lift and allow them to hover in a stationary position. However, to maintain stability in a helicopter, a pilot must constantly adjust the primary controls such as the cyclic stick, collective stick and rudder pedals. In order for the helicopters to lift the load together, they must redirect some of their thrust from lift to counter the horizontal forces pulling the helicopters together. These complex maneuvers further require a pilot to communicate his own efforts with other pilots, thereby increasing cognitive loading on the pilots. It is therefore very difficult and dangerous for multiple helicopters to fly in formation or in close proximity to one another.
[0005] Alternative methods for improving the safety and reliability of two or more helicopters operating in close proximity have been developed. For example, U.S. Pat. No. 3,746,279 describes a “spreader bar” connected to a mass and tethered to each participating helicopter. The purpose of this bar is to reduce the need of the helicopters to lean away from one another while in hover. However, the spreader bar incurs the disadvantage of set-up time and effort to attach the spreader bar, while incurring a weight penalty on the payload capacity. The patent also describes a leader aircraft that is coupled to the controls of the other aircraft. The close coupling between the leader and slave aircraft creates a dependency, such that a failure in the leader aircraft may result in the overall failure of the flight system.
[0006] Further, U.S. Pat. No. 3,656,723 describes a single truss network to fix all helicopters into a rigid formation. In this system, a single pilot can simultaneously direct the system using the same control signal that is relayed to the network of helicopters. This has the advantages of eliminating pilot to pilot communication error as well as preventing any mid air collisions by failed coordination. However, a truss network for helicopters does not easily accommodate variances to the type or quantity of employed helicopters in the formation. Also, if a single helicopter has a mechanical failure it not only ceases to provide lift, but becomes a liability to the rest of the system. An inoperable helicopter becomes a parasitic load because it is permanently fixed to the truss.
[0007] Other prior art include U.S. Pat. No. 5,521,817, which describes a method for semi-autonomous control of multiple aircraft. This control system demonstrates how a single unmanned drone can lead a group of followers. This lead drone, which is remotely controlled from the ground, relays flight information to the followers. As the group moves, the followers react to the relative movement of surrounding drones to prevent mid air collisions. However, the drones of this system cannot function as a group to accomplish a task beyond relocation. As discussed earlier, the coordination of multiple aircraft to lift a common payload requires a more robust and precise control system that considers the dynamic and kinematic effects of a swinging payload.
[0008] Therefore, it is an object of the invention to obviate or mitigate at least one of the above-mentioned problems.
SUMMARY
[0009] The semi-autonomous system for multiple aircraft lifting a common load comprises of at least two aircraft, a single payload, and a pilot station, which allows a single pilot to control the swarm in a remote and safe environment.
[0010] The payload is connected to each aircraft through tethers and anchors. A tether extends from each aircraft's tethering anchor to the payload's tethering anchor. The anchors allow the tethers to be easily attached or released, and also prevent tangling. The location and orientation of the payload is determined through sensors, for example a Global Positioning System.
[0011] Each aircraft has autonomous flight capabilities and, therefore, can stabilize and move to different locations without a pilot. The autonomous flight functionality is implemented through a swarm avionics unit, which interacts with the aircraft's flight controller. The swarm avionics unit receives control signals from the pilot station and transmits aircraft sensory data to the pilot station. Sensory data about the aircraft and payload are used to stabilize and guide the aircraft through a flight controller algorithm.
[0012] Command of the entire multi-aircraft lifting system takes place at a remotely located pilot station. The pilot does not control the aircraft movement directly but, instead, inputs commands regarding the desired location of the payload. A payload waypoint controller calculates intermediary waypoints between the current and desired positions. These payload waypoints are used by the swarm waypoint controller to generate individual waypoints for each aircraft. These aircraft waypoints are then transmitted wirelessly to the swarm avionics unit on each aircraft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The features of the invention will become more apparent in the following detailed description in which reference is made to the appended drawings wherein:
[0014] FIG. 1 is a schematic representation of a configuration for a multi-aircraft lifting system.
[0015] FIG. 2 is a schematic of an alternate configuration to FIG. 1 .
[0016] FIG. 3 is a schematic of yet another configuration to FIG. 1 .
[0017] FIG. 4 is a diagram of several swarm patterns for a multi-aircraft lifting system.
[0018] FIG. 5 is a schematic representation of the functionalities and hardware for a multi-aircraft lifting system.
[0019] FIG. 6 is a schematic representation of the swarm avionics.
[0020] FIG. 7 is a schematic representation of the payload avionics.
[0021] FIG. 8 is a flowchart of the control system for a multi-aircraft lifting system.
[0022] FIG. 9 is a flowchart of a detailed control system for a multi-aircraft lifting system.
[0023] FIG. 10 is a schematic of relative positioning between a swarm and a payload.
[0024] FIG. 11 is another schematic of relative positioning between a swarm and a payload.
[0025] FIG. 12 is another schematic of relative positioning between a swarm and a payload with tethers of different lengths.
[0026] FIG. 13 is another schematic of relative positioning between a swarm and a payload with aircraft in contact with one another.
[0027] FIG. 14 is another schematic of relative positioning between a swarm and a payload with tether separating structures.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Referring to FIG. 1 , a semi-autonomous multi-aircraft lifting system comprises of several aircraft 11 , 12 , 13 , operating in formation attached to a single payload 14 by means of tethers 15 . Aircraft hereon refers to vehicles capable of hovering such as, by way of example, the UH-1 helicopter, V22 Osprey, F-35 Joint Strike Fighter, and a lighter-than-air airship or dirigible. Examples of heavy lifting airships include SkyHook International's JHL-40, CargoLifter's CL160 Super Heavy-Lift Cargo Airship and DARPA's Walrus heavy transport blimp. The number of aircraft in the multi-aircraft system may range from two to n units, and are labeled H 1 11 , H 2 12 , and H n 13 . A multi-aircraft lifting system has the advantage over a single aircraft in being capable of lifting a payload weight that is greater than a single aircraft's lift capacity. In other words, if a single aircraft carries x kg, then n aircraft can carry a payload of up to nx kg. A group of aircraft flying together will hereon be referred to as a swarm 18 . Note that the aircraft within the swarm 18 are not required to be of the same type as to allow different aircraft to operate within the multi-aircraft lifting system.
[0029] Continuing with FIG. 1 , it should be appreciated that a pilot is not required to operate each of the aircraft 11 , 12 , 13 . Instead, a pilot station 16 , requiring a minimum of one operator or pilot, operates the multi-aircraft lifting system. The pilot station 16 may be located in a ground base 17 for remote operation. Alternatively, as shown in FIG. 2 , the pilot station 16 may be located in a vehicle, for example, an aircraft 21 , that is ancillary to the swarm 18 . In yet another embodiment, referring to FIG. 3 , the pilot station 16 may be located within one of the swarm's aircraft. These pilot configurations advantageously allow for a reduced number of human operators and can allow a human operator to remain at a safe distance from the lifting procedure. It is also appreciated that the piloting operations may not require a human operator as many control systems are well known to automatically pilot aircraft.
[0030] It should also be appreciated that the number of aircraft that compose the swarm 18 affects the flight formation pattern as shown from a top-down perspective in FIG. 4 . In a two-aircraft swarm formation 43 , comprising aircraft 11 , 12 , the aircraft are positioned 180° from each other to facilitate equal tension in the tethers and, thereby facilitating the stability in transport of the payload. Similarly, for a three-aircraft swarm formation 44 (comprising 11 , 12 , 41 ), the aircraft are positioned 120° apart, while for a four-aircraft swarm formation 45 (comprising 11 , 12 , 41 , 42 ), the aircraft are positioned 90° apart. Note that the number of aircraft in the swarm is not limited to four.
[0031] Moreover, any swarm formation that allows multiple aircraft to lift a common payload is applicable to the principles herein. In some situations, it may be preferable that the aircraft are configured in an irregular formation, for example, to accommodate different payload sizes and uneven weight distribution. Aircraft in a swarm may be of a different type, each with different lifting and flight performance capabilities. Thus, it may also be preferable to configure swarm lifting formations based on aircraft type.
[0032] Referring to FIG. 5 , the components of the multi-aircraft lifting system is shown in further detail. A representation of a two-aircraft swarm consisting of aircraft H 1 11 and H 2 12 are carrying a payload 14 . Within each aircraft 11 , 12 there is a swarm avionics unit 502 that gathers sensory and flight data to determine flight control commands. The computed flight control commands are sent to the aircraft's flight system 503 , which is an electrical interface to the aircraft's actuators 504 . By way of background, a highly complex flight system may have autopilot functionality to control the aircraft's actuators 504 . Common helicopter actuators include, but are not limited to, tail rotor motors, main rotor motors, flapping hinge actuators, and pitch control rod actuators. Common airship actuators include rotors, flaps, thrust vectoring devices, ballasts, ballonet valves, means for filling and emptying the airship with lifting gas, and devices for heating and cooling the lifting gas within the airship.
[0033] The swarm avionics unit 502 is a critical part of the swarm control system as shown in detail in FIG. 6 . The swarm avionics unit 502 comprises a sensor suite 614 that collects data about the aircraft through a variety of sensors. Specifically, the sensor suite 614 should output data directly or indirectly pertaining to an aircraft's angular and translational position, velocity, and acceleration, and any sensors able to provide such data are applicable to the principles described herein. The sensor suite 614 may include a Global Positioning System (GPS) 601 , which provides absolute position, absolute speed, and a reference of merit for the sensor suite's output data. Similarly inertial sensors 602 , typically consisting of accelerometers and gyroscopes, provide absolute speed, attitude, heading, and a reference of merit for the sensor suite's output data. Object detection sensors 605 , for example, ultrasound and infrared, provide distance measurements between the payload, aircraft, and other objects. Radar 606 provides relative distances to other aircraft. An altimeter 607 provides the altitude. A tether sensor 608 provides the magnitude and direction of force from the tether acting on the aircraft.
[0034] Data from the sensor suite 614 is sent to the swarm avionic unit's processor 609 for real-time data processing. Processed aircraft data is wirelessly transmitted to the pilot station 14 through the communication unit 611 , which includes a transceiver 612 and receiver 613 . The processor 609 also receives swarm waypoint control signals from the pilot station 16 through the receiver 613 . The control signals and the sensor suite data are inputs to the flight control algorithms, which are stored in the memory 610 . The flight control algorithms compute in real-time and output flight control commands. Details regarding the flight control algorithms are discussed further below. Flight control commands are sent from the processor 609 to the aircraft's flight system 503 .
[0035] Referring back to FIG. 5 , the payload 14 is connected to each aircraft 11 , 12 using tethers 15 . Each tether 15 is attached to the aircraft 11 , 12 through an aircraft tethering anchor 505 and similarly, is attached to the payload 14 through a payload tethering anchor 506 . Both the aircraft and payload anchors 505 , 506 have a release mechanism that detaches the tether from the aircraft and payload respectively. The anchors 505 , 506 are also used to reduce tangling during flight manoeuvres. It should be noted that the tethers 15 are not required to be at right angles to the payload tethering anchor 506 in order to maintain equal force distribution in each tether 15 . The payload tethering anchor 506 is easily attachable to variety of surfaces to facilitate short cycle times for setting up a multi-aircraft lifting system.
[0036] It can be appreciated that the tethers 15 need not be flexible and may, instead be or include rigid materials. For example, the tethers 15 may be rigid bars. Any means for attaching the payload 14 to the aircraft 11 , 12 are applicable to the principles herein.
[0037] Attached to the payload 14 is a payload avionics unit 507 that gathers sensory data about the location and orientation of the payload 14 , and transmits the data to the pilot station 16 and the aircraft 11 , 12 . Turning to FIG. 7 , a detailed schematic representation shows that the payload avionics unit 507 consists of inertial sensors 71 to provide absolute speed, attitude, and heading data about the payload 14 . Examples of inertial sensors include, but are not limited to, accelerometers 72 and gyroscopes 73 . Similarly, GPS 74 determines the absolute position and speed. Data from the inertial sensors 71 and GPS 74 are collected and computed by a real-time processor 75 having on-board memory 76 . The processed data is then sent to a communication unit 77 with a transceiver 78 that is capable of transmitting the processed payload sensory data to the pilot station 16 and aircraft 11 , 12 .
[0038] Returning again to FIG. 5 , the pilot station 16 receives data about the payload 14 and individual aircraft 11 , 12 within the swarm 18 through the pilot station's communication unit 511 . Note that the communication unit 511 has a wireless receiver 515 and transceiver 514 . Wireless communication media between the aircraft 11 , 12 , payload 14 and pilot station 16 may include, for example, radio, satellite, Bluetooth, and laser. As shown in dotted lines, the communication unit 511 is in communication with the swarm avionics units 502 and the payload avionics 507 . Similarly, the payload avionics unit 502 is in communication with the swarm avionics units 502 . The received sensory data is processed in real-time by a processor 510 , which then sends the situational data to a computer display and interface 509 for the pilot 508 to view. The pilot 508 uses the current position and velocity of the swarm 18 and payload 14 to determine the flight path of the payload. The pilot 508 then inputs desired positions for the payload, called waypoints, into the computer 509 through interface devices, such as a keyboard, mouse, control stick, or control pad. The pilot's commands are sent to the processor 510 , which holds payload waypoint control algorithms and swarm waypoint control algorithms within the memory 512 . The processor uses the control algorithms to compute swarm waypoint commands for each aircraft within the swarm in order to move the payload to the desired waypoint. Details regarding the payload waypoint and swarm waypoint control algorithms are discussed further below. These waypoint commands are transmitted through the pilot station's transceiver 514 and are received by each aircraft's receiver 613 .
[0039] The above components are used to implement the multi-aircraft lifting system, which is dependent on the control system. The overall function of the multi-aircraft control system is to stabilize and guide each aircraft, while determining the flight path for each aircraft such that the payload 14 moves from its initial position to a final position as commanded by the pilot 508 . Subsidiary functions of the multi-aircraft control system include maintaining a safe distance between aircraft and proper positioning to support the payload 14 .
[0040] Referring to FIG. 8 , an overview of the multi-aircraft lifting control system is shown with respect to the pilot station processor 510 and swarm avionic processors 609 . The main components of the multi-aircraft lifting control system include the payload waypoint controller 802 , the swarm waypoint controller 803 , and the flight control system 806 . The flight control system 806 is implemented for each aircraft 11 , 12 , 13 . The payload waypoint controller 802 and the swarm waypoint controller 803 are run on the pilot station's processor 510 . Similarly, the flight controller 804 and aircraft plant model 805 , within the flight control system 806 , are run on the swarm avionics processor 609 .
[0041] A benefit of the preferred embodiment is shown more clearly in FIG. 8 . The control of the swarm is not localized to an aircraft and, instead, is ancillary to the aircraft. This mitigates or obviates the need for an aircraft leader for the swarm 18 . Therefore, in the event an aircraft fails, the multi-aircraft lifting system has the robustness to continue supporting the payload 14 . For example, four aircraft, each capable of lifting 500 kg, are transporting a 1200 kg payload in a swarm pattern 45 spaced 90° apart. If a flight control system 806 on one of the aircraft fails, the anchors 505 , 506 will allow the failed aircraft to leave the swarm 18 . The three remaining aircraft then adapt by forming a different swarm pattern 44 spaced 120° apart, while the payload waypoint controller 802 and swarm waypoint controller 803 continue to navigate the swarm 18 .
[0042] Continuing with the control system in FIG. 8 , the payload waypoint controller 802 monitors and controls the payload state variables, such as payload acceleration, velocity, position, and orientation. The payload waypoint controller 802 also generates a path along which the payload 14 will travel from its current state to the desired payload state as determined by the pilot 508 . The payload's path is formed by generating appropriate waypoints between the initial and final states, and calculates a path from the payload's initial state to the first waypoint. The path is mathematically interpolated, by way of example, through multiple splines that are used to determine the value of each state at a certain time t. This path is sent to the swarm waypoint controller 803 , which coordinates the individual aircraft within the swarm 18 to obtain the desired payload state at time t. It should be appreciated that other interpolation methods, such as Bezier curves, discrete steps, and linear interpolation may be used in place of splines. Other path planning controllers that may be used include fuzzy-logic and Bang-bang controllers.
[0043] The swarm waypoint controller 803 uses the previously generated payload path to determine the relative orientations and positions for all of the individual aircraft. Turning to FIG. 10 , a positioning configuration for four aircraft, by way of example, is shown. The positions on each aircraft 11 , 12 , 41 , 42 , relative to the payload 14 , is determined by two constants. The first constant is the height difference H between the payload 14 and the swarm plane 101 , and second constant is the radius R between each aircraft 11 , 12 , 41 , 42 to the center of the swarm plane 101 . It should be noted that the swarm plane 101 , as shown by the overhead view 102 , is described by a circle of radius R, in which each aircraft 11 , 12 , 41 , 42 is positioned at the circumference of the circle and separated by a constant angle θ, where θ=360°/(number of aircraft). In the example of a four aircraft swarm, the angular separation θ is 90°. Furthermore, if the length L of the tethers 15 are of the same length, then all points within the swarm plane 101 , including each aircraft, should have the same altitude. As seen by the front profile 103 , the payload 14 is located directly below the center of the swarm plane 101 by a height difference H. It should be appreciated that the R and H constants are determined by considering many factors, including, for example, the size of the aircraft, the number of aircraft, the desired horizontal to vertical force ratios, and the size of the payload. The tethers 15 between the payload 14 and aircraft 11 , 12 , 41 , 42 all have the same length, L, which is approximated by the Pythagorean relationship L=(R 2 +H 2 ) 1/2 . Thus, the swarm waypoint controller 803 maintains the relative positioning based on the constant radius R of the aircraft and the payload's height H below the swarm plane 101 .
[0044] Turning to FIG. 11 , the payload 14 may be very large where it is advantageous for each aircraft 11 , 12 to support different portions of the payload 14 . During a straight-path transport, the swarm waypoint controller 803 ensures that each aircraft 11 , 12 maintains a relative position to each other and the payload 14 , whereby the tethers 15 remain approximately vertical.
[0045] In FIG. 12 , the payload 14 is very large and has an irregular shape. Three aircraft 11 , 12 , 13 are attached to the payload 14 using various lengths of tethers, such that each aircraft has different elevation relative to each other. The swarm waypoint controller 803 ensures that each aircraft 11 , 12 , 13 maintains their relative elevations to ensure that equal tension. It can further be appreciated that the H1 ( 11 ) may be a helicopter, while H2 ( 12 ) and Hn ( 13 ) may be airships. In such a case, the swarm waypoint controller 803 would also need to take into account various flight performance specifications, such as lifting power, to maintain the relative orientations of the aircraft and payload 14 . It can thus be seen that the swarm waypoint controller 803 can be configured to maintain various relative positioning formations between the aircraft in the swarm 18 and the payload 14 .
[0046] Returning to FIG. 8 , this swarm waypoint controller 803 calculates the payload states based on the states of each aircraft; the payload position may be determined from the position of all aircraft relative to ground and the Euclidian distance from each aircraft to the payload. Alternatively, the payload position may be determined by the payload avionics unit 507 . Each aircraft body 11 , 12 in the swarm 18 affects the position of the payload body 807 and consequently, the payload sensors' 507 readout. The computed payload state information is sent to the payload waypoint controller 82 .
[0047] This swarm waypoint controller 803 generates waypoints to guide each aircraft while the payload 14 moves along the desired path. These intermediate waypoints ensure that each aircraft is properly positioned relative to each other such that the payload force is equally distributed to each aircraft. In other words, where the lifting power of each aircraft is similar, the tension force in the tethers 15 should be approximately equal. Multiple spline paths are calculated to provide a means to determine each state for each aircraft at a certain time t. The swarm waypoint controller 803 provides the reference signal to each individual flight control system 806 within the swarm 18 using the spline paths that were previously generated.
[0048] The flight control system 806 is responsible for the flight and stability of an individual aircraft. The flight control system 806 calculates the required actuation signals necessary for the plant model 805 to track the reference control signal provided by the swarm control system 803 . The flight control system 806 is also responsible for tracking the reference signal within a specified tracking error and overshoot, as specified later in more detail. Achieving these flight control system specifications allows the aircraft actuators 504 to position the aircraft body 11 , 12 at a safe distance from each other and at the proper locations to support the payload 14 , as was determined by the swarm waypoint controller 803 . This flight control system 806 then returns the observed state of the aircraft to the swarm waypoint control system 803 .
[0049] The method for the multi-aircraft lifting control system is shown in further detail in FIG. 9 . The control algorithm is divided amongst three main controllers, being the payload waypoint controller 802 , the swarm waypoint controller 803 , and the flight controller 804 . Within the payload waypoint controller 802 , the pilot interface 509 is used to receive the desired payload destination 801 , which is then used for the next payload waypoint calculation 902 . The next payload waypoint calculation 902 and the current payload state 901 are then used to determine the spline end-conditions for position, velocity, and acceleration of the payload 903 by way of numerical methods. It should be noted that the current payload state 901 is outputted from the swarm waypoint controller 803 . The data from this spline calculation 903 is inputted back into the next payload waypoint calculation 902 , forming a recursive relationship. The spline output from step 903 is then used to compute the desired state at time t for the payload 904 .
[0050] With regard to the swarm waypoint controller 803 in FIG. 9 , the controller 803 uses all aircraft states 905 and the next payload waypoint 908 as inputs. The aircraft states 905 originate from the flight controller 804 of each aircraft in the swarm 18 , and the next payload waypoint originates from the step 904 in the payload waypoint controller 802 . The aircraft states 905 are used in the calculation of the current payload state 906 . The current payload state 906 and the next payload waypoint 908 are then used in step 907 for computing the desired state of each aircraft in the swarm 18 . After step 907 , the desired aircraft states are inputted into the step 909 , where the next waypoints for each helicopter are calculated and then used to generated splines for each aircraft in step 910 . These splines for position, velocity, and acceleration are used to derive the current state for each aircraft at time t 911 , and to calculate step 906 . Note that steps 906 , 907 , 909 , and 910 form a recursive relationship within the swarm waypoint controller 803 .
[0051] The desired states 911 for each aircraft are transmitted to the corresponding flight controllers 804 , as shown in FIG. 9 in the example of a single flight controller 804 . In other words, for an n aircraft swarm 18 , the swarm waypoint controller 803 will generate n desired aircraft states 911 , which are then transmitted to each of the n corresponding flight controllers 804 residing on each aircraft's processor 609 . The desired aircraft state is considered the reference signal R 916 in a flight controller 804 . It should be appreciated that the implementation of the flight controller 804 discussed herein is only one embodiment of the multi-aircraft lifting system. Alternate closed-loop control configurations may be used to stabilize and guide the movement of the aircraft.
[0052] Referring to FIG. 9 , the reference signal R 916 is compared against the observed state {circumflex over (X)} of the aircraft. The difference between R and {circumflex over (X)} is used to compute the gain K in step 917 , which then generates an input value u that is fed into the plant model 912 and the observer 915 . The plant model 912 represents the mechanics and dynamics of the aircraft through mathematical relations. Typical values in the plant model include the position and velocity in a Cartesian coordinate frame, and the roll, pitch, and yaw of the aircraft. The actual state variables X of the aircraft are derived from the plant model 912 , and are filtered by the observer matrix C 913 . The observer matrix 913 selects a subset of states from matrix K that are passed into the observer 915 . This embodiment of the flight controller 804 also takes into account disturbances, for example crosswinds, through the disturbance matrix D 914 . The disturbances may cause the measured state values, y, to differ from the actual state variables, X.
[0053] The observer 915 is used to estimate state variables that may not be measured directly. The observer estimates the state of the aircraft {circumflex over (X)} through the relation {circumflex over ({dot over (X)}=A{circumflex over (X)}+BU+L{tilde over (Y)}, where {tilde over (Y)}=Y−Ŷ. The matrices A and B represent the plant model, while matrix L, is designed to drive the difference between measured state values Y and estimated measured state values Ŷ to zero, thereby driving {circumflex over (X)} to X. The estimated state {circumflex over (X)} for each helicopter is sent to the swarm waypoint controller 803 , and is collected in a matrix 905 .
[0054] In another embodiment of the multi-aircraft control system, the flight controller 804 may not require an observer as enough data may be available to accurately measure the all states of the aircraft.
[0055] In another configuration of the relative positioning between aircraft, and airships in particular, the body of the aircraft may be constructed in such a way that the body of the aircraft are touching while flying in a swarm formation. In FIG. 13 , three aircraft 11 , 12 , 13 are shown flying in formation while in contact with each other. It can be appreciated that any number of aircraft may fly in such a formation. In particular, airship bodies may be in contact if the envelope, or skin, or the airship provides sufficient force to withstand the forces exerted by another airship in contact. Moreover, the thrusters, ailerons or other external structures are positioned in locations on the airship envelope where there is no contact. Such structures, for example, may be positioned towards the top region of the airship. Alternatively, the external structures may be configured or protected to allow for contact with another airship, whereby no damage is done to the airship or external structure. This swarm configuration advantageously allows multiple aircraft to lift a smaller sized payload 14 . This swarm configuration also advantageously allows for the tethers or connecting means 15 to attach on to the payload 14 at a centralized location. As can be understood, the swarm waypoint controller 803 generates waypoints to guide each aircraft, such that they maintain a certain relative positioning taking into account that the aircraft are in contact with each other.
[0056] Another configuration of multiple aircraft is shown in FIG. 14 where tether separating structures 402 , 404 , 406 are used an intermediary between the aircraft 11 , 12 , 13 and the payload 14 . For each aircraft, there is preferably a corresponding separating structure. Each separating structure is made of a rigid or semi-rigid body, whereby the separating structures can withstand external compression forces. They are preferably constructed to be light weight and, for example, include carbon fibre, steel tubing and fabrics. As the separating structures are pressing against one another, the separating structures are preferably rounded and have smooth outer surfaces to allow the separating structures to slide against each other. In particular, the tethers 15 extend from the payload 14 at a centralized location, such as a payload anchor 506 . Each tether 15 extends upward from the payload 14 at an angle towards a respective tether separating structure 402 , 404 , 406 . The tethers 15 above the separating structures extend approximately vertical towards each respective aircraft 11 , 12 , 13 . It can be appreciated that the separating structures are sufficiently large to allow an aircraft to fly without exerting additional horizontal forces to be at a distance away from another aircraft in the swarm. This configuration is used in combination with the swarm waypoint controller 803 to maintain relative positions of the aircraft and payload 14 .
[0057] Possible applications of the multi-aircraft lifting system include transporting an entire building, such as a warehouse. This has particular utility in oil and mining operations in remote locations, where drilling and mining sites are moved frequently. In remote locations where there is limited accessibility by land or water, it is advantageous to transport building structures by air. For example, for drilling operations in the Arctic or Antarctic regions, there are often little to no roads. A fleet of heavy lift airships may be deployed to transport buildings, equipment and vehicles in such remote regions. Some of the airships in the fleet are used to individually carry smaller or lighter payloads. Other airships within the fleet are used to form a swarm to carry larger or heavier payloads. The number of airships and the formation of the swarm may be configured to meet the payload's weight and size. Thus, the multi-aircraft system is flexible to the lifting operation. Further, transporting entire buildings, rather than components of a building for assembly and disassembly, reduces the assembly or set-up time for the oil and mining operations. This advantageously allows the oil and mining operations to achieve operational status in shorter times.
[0058] In another application, the multi-aircraft lifting system may be used to transport assembled large marine vessels from land to water, and vice versa. This would advantageously allow ship and submarine manufacturers to construct or repair marine vessels inland, away from the water. Transporting large marine vessels using the multi-aircraft system would also allow marine vessels to be launched in locations that are further away from land, where the water depth is preferable.
[0059] It can be appreciated that constructing, maintaining and storing multiple smaller aircraft may be more economical. Further, the aircraft in a multi-aircraft lifting system can be used for multiple purposes, in addition to heavy lifting. For example, an aircraft in one situation is used to transport passengers. In another situation, the same aircraft cooperates with other aircraft to form a swarm for lifting a common payload. A multiple-aircraft lifting system further provides redundancy and reliability. For example, should an aircraft in the swarm fail or be removed from the swarm for other reasons, the remaining aircraft in the swarm continue to lift the payload.
[0060] Although the multi-aircraft lifting system has been described with reference to certain embodiments, various modifications thereof will be apparent to those skilled in the art without departing from the spirit and scope of the multi-aircraft lifting system as outlined in the claims. | A system and method are provided for controlling a plurality of aircraft to lift a common payload. The system comprises of multiple aircraft tethered to a common payload, where the group of aircraft form a swarm that is controlled by a pilot station. Each aircraft is autonomously stabilized and guided through a swarm avionics unit, which further includes sensor, communication, and processing hardware. At the pilot station, a pilot remotely enters payload destinations, which is processed and communicated to each aircraft. The method for controlling a multi-aircraft lifting system includes of inputting the desired location of the payload, and determining a series of intermediary payload waypoints. Next, these payload waypoints are used by the swarm waypoint controller to generate individual waypoints for each aircraft. A flight controller for each aircraft moves the aircraft to these individual waypoints. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a data processing apparatus for obtaining structural information regarding unknown compounds by searching for the mass spectra of such unknown compounds in a mass spectrum database of known compounds, the mass spectra of such unknown compounds being gained by using mass spectrometry that is capable of MS n .
[0003] 2. Background Art
[0004] In order to measure unknown compounds using mass spectrometry and to determine the structure thereof, a mass spectrum database of known compounds is widely used for searching for the mass spectrum of an unknown compound gained by measurement. JP Patent Publication (Kokai) No. 11-64285 A (1999) (Patent Document 1) and JP Patent Publication (Kokai) No. 2001-50945 A (Patent Document 2), for example, disclose mass spectrum database search methods.
[0005] Mass spectrometry uses an apparatus for separating and detecting a sample on the basis of the ratio of mass to charge (m/z), the sample being ionized using an ion source. In this case, a usual mass analysis method is referred to as MS 1 , by which a sample ionized at the beginning using an ion source is detected as such. A method for obtaining a second mass spectrum is referred to as MS 2 , by which the second mass spectrum is obtained by providing energy to ions (precursor ions) of a specific mass for fragmentation, the specific mass being in a mass spectrum obtained in MS 1 , and by separating the masses of a plurality of generated product ions.
[0006] Each bond in a sample molecule has a different likelihood of cleavage in accordance with the structure of the relevant molecules. Thus, fragment ions in a mass spectrum gained in MS 2 have differing intensities, and show molecule-specific mass spectrum patterns. In other words, when different compounds show the same mass spectrum pattern in an MS 1 spectrum, they show different mass spectrum patterns in an MS 2 spectrum. Thus, more accurate identification is possible by searching the MS 2 spectrum along with the MS 1 spectrum using a database. JP Patent Publication (Kokai) No. 8-124519 A (1996) (Patent Document 3), JP Patent Publication (Kokai) No. 2001-249114 A (Patent Document 4), and U.S. Pat. No. 6,624,408 (Patent Document 5) show examples of a database search method using the MS 2 spectrum.
[0007] Conventionally, the object of database search for unknown compounds is to identify unknown compounds. Under such object, it is necessary that the unknown compounds and known compounds searched for in a database have the same molecular weight, so that it is meaningless to search for mass spectra whose generations are different (have different n values) to each other, when searching MS n spectra. Thus, in conventional database search, among the MS n spectra of unknown compounds and known compounds, mass spectra whose generations are the same, such as MS 1 for MS 1 , MS 2 for MS 2 . . . are compared.
Patent Document 1: JP Patent Publication (Kokai) No. 11-64285 A (1999) Patent Document 2: JP Patent Publication (Kokai) No. 2001-50945 A Patent Document 3: JP Patent Publication (Kokai) No. 8-124519 A (1996) Patent Document 4: JP Patent Publication (Kokai) No. 2001-249114 A Patent Document 5: U.S. Pat. No. 6,624,408
SUMMARY OF THE INVENTION
[0013] Generally, biopolymers such as carbohydrates and peptides, for example, have many series of related compounds including various types of different side chains at the same principal chain. In the structural analysis thereof, when the structure of the principal chain is determined in accordance with the MS n spectrum of a cleaved principal chain, the analysis of the entire structure is possible by estimating the side chains on the basis of the structure of the principal chain, even if the entire structure is not clear. However, depending on compound, a series of related compounds has different numbers of MS n generations (n) ( FIG. 1 ) necessary to gain a mass spectrum pattern when a bond in the principal chain that shows the structure of the principal chain is cleaved in accordance with the number and types of bound side chains. Consequently, structural comparison that focuses on the principal chain has been impossible in conventional search methods by which, among MS n spectra of each compound, mass spectra of the same generation are compared.
[0014] Also, compounds that have a multitude of structural isomers in which a plurality of structural units that have the same mass are bound, such as carbohydrates, have a multitude of isomers whose molecular weights are equivalent to one other. Thus, in many cases, although the same mass spectrum patterns are shown in MS 1 , they result in different compounds. Consequently, it is difficult to accurately determine or identify structure via conventional database search methods.
[0015] It is an object of the present invention, in database searches for MS n spectra, to enable searching for a known compound whose principal chain is identical to that of an unknown compound even if the entire structure of the known compound in a database and that of a measured unknown compound is not identical so as to readily analyze the entire structure.
[0016] In order to achieve the aforementioned object, the present invention provides a data processing apparatus for mass spectrometry. The data processing apparatus is capable of MS n analysis of an ionized sample, and is provided with a database for storing mass spectrum data obtained as a result of MS n analysis of known compounds by each compound, and for searching for the mass spectrum data by comparing the mass spectrum data with MS m spectra (m≧1) obtained as a result of MS m analysis of unknown compounds. The data processing apparatus is characterized in that it has a function of searching MS n data involving differing generations, upon database search.
[0017] The MS m spectrum of an unknown compound that is a comparison target in the present invention, is characterized in that the MS m spectrum of the unknown compound is that with the smallest value of m among those mass spectra such that their intensity ratios of base ions to other ions are greater than a threshold.
[0018] The present invention is also characterized in that the MS m measurement of unknown compounds ends when the intensity ratio of the base ions to other ions in the MS m spectrum exceeds the threshold.
[0019] The present invention is further characterized in that the number m of mass spectra obtained as a result of the MS m analysis of unknown compounds are compared with all the mass spectra in a database successively from m=1, depending on the structure of the database.
[0020] According to the present invention, in the MS n measurement of a series of related compounds including various types of different side chains with the same principal chain, such as in the case of biopolymers, it is possible to determine the structure of the principal chain using a database search even if the entire structure is not clear. And the estimation of the entire structure is possible on the basis of the principal chain structure. Further, in a database search for determining the structure of a principal chain, it is possible to determine the structure of related compounds whose number is greater than that of known compounds registered in a database.
[0021] Moreover, in the MS n measurement of compounds that have a structure where a plurality of structural units that have the same mass are bound and the molecular weights of isomers are equivalent to each other, it is possible to identify the isomers using a database search even if the mass spectrum patterns in the results of MS 1 are the same.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 shows conceptual diagrams of a database search method according to the present invention.
[0023] FIG. 2 shows a schematic diagram of mass spectrometry according to the embodiments of the present invention.
[0024] FIG. 3 shows diagrams of the structures of two types of sugar chains used in the embodiments of the present invention.
[0025] FIG. 4 shows mass spectra gained in MS 2 and MS 3 analyses of the two types of sugar chains used in the embodiments of the present invention.
[0026] FIG. 5 shows a schematic diagram of the database search method in a first embodiment of the present invention.
[0027] FIG. 6 shows a diagram describing a data processing method in the first embodiment of the present invention.
[0028] FIG. 7 shows a schematic diagram of the database search method in a second embodiment of the present invention.
[0029] FIG. 8 shows a diagram describing the data processing method in the second embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] In the following, the embodiments of the present invention are described.
Embodiment 1
[0031] FIG. 2 shows the structure of mass spectrometry used in the embodiments of the present invention. The mass spectrometry according to the present invention comprises an ion source 1 for ionizing a sample, an ion trap type mass separating unit 2 for the mass separation of generated ions, the ion trap type mass separator being capable of MS n , a detector 3 for detecting the mass-separated ions, controller 4 for the control thereof, a data processing unit 5 , signal wires 6 for the connection thereof, and a display unit 7 for displaying measurement data and search results. The ion source 1 can employ a sonic spray ion source and an ion spray and a matrix-assisted laser desorption ion source, besides an electrospray source.
[0032] Sample ions ionized by the ion source 1 are introduced into the mass separating unit 2 . In the mass separating unit 2 , the sample ions are mass-separated. Also, MS n (n=2, 3, 4 . . . ) is successively conducted in accordance with the setting performed by an observer. The mass-separated sample ions are sent to the detector 3 and detected in the form of a mass spectrum. The mass spectrum is sent to the data processing unit 5 for processing via the signal wire 6 , and is displayed via the display unit 7 .
[0033] FIG. 3 shows the structures of two types of sugar chains used in the present embodiment. On the basis of the nomenclature of Takahashi et al. described in Analytical Biochemistry, 1988, No. 171, page 73, these are referred to as 200 . 2 ( FIG. 3 a ) and 210 . 2 ( FIG. 3 b ). Although they have the same principal chains, sugar chain 210 . 2 has fucose (Fuc) bound to glucose (Glc) at the end thereof.
[0034] FIG. 4 shows the result of the MS n analysis of the two types of sugar chains.
[0035] A sugar chain has a structure where a principal chain in which a multitude of sugars are bound is induced by various side chains. When the sugar chain is subjected to MS n measurement, cleavage is caused successively from the bond between the principal chain and the side chains. Thus, the number of generations (n) for MS n required for the bond in the principal chain to be cleaved differs depending on compounds. Also, the sugars constituting the principal chain of the sugar chain are isomers that have masses equivalent to one other, so that it is difficult to identify the structure of the principal chain on the basis of daughter ions corresponding to the principal chain, the daughter ions being gained by the desorption of the side chains upon MS n−1 . Thus, it is necessary to conduct MS n until the principal chain is cleaved.
[0036] In FIG. 4 , charts (a) and (b) show the mass spectra of 200 . 2 in MS 1 and MS 2 , and charts (c) to (e) show the mass spectra of 210 . 2 in MS 1 to MS 3 . In MS 1 , only molecular ions are generated and only those molecular ions (m/z 790, 863) of 200 . 2 and 210 . 2 are detected (charts (a) and (c)). When MS 2 is conducted, in 200 . 2 , each bond in the principal chain is cleaved and a plurality of fragment ions are generated (chart (b)). The generation pattern of the fragment ions shows structural information of the principal chain of 200 . 2 . By contrast, in the MS 2 of 210 . 2 , only the bond between the principal chain and the side chain (Fuc) is cleaved, so that only those daughter ions (m/z 790) corresponding to the principal chain are detected. Consequently, structural information about the principal chain cannot be obtained (chart (d)). When MS 3 is further conducted concerning 210 . 2 , each bond in the principal chain is cleaved and a plurality of fragment ions are generated (chart (e)). It is learned that the principal chains of 200 . 2 and 210 . 2 are the same in accordance with the similarity between the pattern of the MS 3 spectrum showing structural information of the principal chain of 210 . 2 and the pattern of the MS 2 spectrum of 200 . 2 .
[0037] In this case, when the MS n measurement of unknown compounds is conducted, one method enables measurement allowing an observer to estimate sufficient n for the number of generations (n) of MS n in advance such that it allows the principal chain of unknown compounds to be cleaved, and to specify n regarding measurement conditions.
[0038] Also, by setting a threshold for the intensity ratio of the base ions, which represent the strongest peak in a mass spectrum, to other ions in advance, it is possible to determine a mass spectrum in which the intensity ratio exceeds the threshold as a mass spectrum that shows structural information about the principal chain. On the basis of this, MS n relative to the base ions can be automatically repeated until a mass spectrum that shows structural information about the principal chain can be obtained. For example, in the aforementioned case, measurement can be automatically conducted up to MS 2 in 200 . 2 and MS 3 in 210 . 2 by establishing conditions whereby the principal chain is determined to be cleaved when the intensity of other ions exceeds 40% of the intensity of the base ions in a mass spectrum. A percentage from 10% to 50% is suitable for the threshold.
[0039] A case is considered where the MS 2 spectrum of 200 . 2 from data gained as mentioned above is registered in a database, and the results of MS 3 analysis of 210 . 2 are searched for in the database ( FIG. 5 ).
[0040] In the present invention, a mass spectrum that best shows structural information of the principal chain in the results of MS 3 analysis of 210 . 2 is first selected from among the three mass spectra of MS 1 , MS 2 , and MS 3 .
[0041] This selection method has two methods regarding the MS n analysis method for 210 . 2 .
[0042] If measurement is conducted by specifying the number of MS n generations (n) regardless of mass spectrum patterns, a mass spectrum that shows the structure of the principal chain is selected from the number n of gained mass spectra. The selection is carried out by determining a mass spectrum with the smallest n as the mass spectrum in which the principal chain is cleaved among mass spectra such that the intensity ratio of other ions to the base ions in the mass spectrum is not less than a certain threshold. In the case of 210 . 2 , when the threshold is set as 40%, the MS 3 spectrum in which the intensity of other ions to the base ions exceeds 40% is selected. A percentage from 10% to 50% is suitable for the threshold.
[0043] In contrast, if the MS n measurement of 210 . 2 is conducted by automatically determining a mass spectrum in which the principal chain is cleaved, the mass spectrum that shows the structure of the principal chain is a mass spectrum gained as the end of the MS n measurement; namely, the MS 3 spectrum. Thus, it is selected.
[0044] The selected MS 3 spectrum is compared with all the mass spectra registered in the database. As a result, the MS 2 spectrum of 200 . 2 that shows a similar mass spectrum pattern is displayed as a search result, and the principal chain of 210 . 2 is determined to be the same as that of 200 . 2 . An observer can analyze each mass spectrum of MS 1 and MS 2 using determined principal chain information, and can determine the entire structure ( FIG. 6 ).
Embodiment 2
[0045] The second embodiment includes the constitution of the first embodiment shown in FIG. 1 and gained data of 200 . 2 and 210 . 2 shown in FIG. 4 , and the database for storing MS n spectra has a hierarchical structure such that n=1, 2, 3 . . . . Also, two mass spectra of MS 1 and MS 2 are registered in the database as a result of the MS 2 measurement of 200 . 2 , and the results of the MS 3 analysis of 210 . 2 are searched for in the database ( FIG. 7 ).
[0046] In the present invention, an MS n spectrum (n≧1) of 210 . 2 is first compared with all the mass spectra registered in the database successively from n=1 and any similar mass spectra are selected. In the present embodiment, the MS 1 spectrum of 200 . 2 that is similar to the MS 2 spectrum of 210 . 2 is selected. This comparison determines a mass spectrum that shows daughter ions corresponding to the principal chain.
[0047] Then, concerning both a selected MS m spectrum of an unknown compound and the MS 1 spectrum in the database, the MS m+1 spectrum and the MS 1+1 spectrum are compared. In the present embodiment, the MS 3 spectrum of 210 . 2 and the MS 2 spectrum of 200 . 2 in the database are compared. The comparison is conducted between the MS m spectrum and the MS n spectrum in which the base ions are cleaved. As a result, search results are displayed in descending order of similarity, and the principal chain of 210 . 2 is determined to be the same as that of 200 . 2 ( FIG. 8 ).
[0048] Using determined principal chain information, an observer can determine the entire structure by analyzing each mass spectrum of MS 2 and MS 1 . | In a database MS n spectrum search, search of a known compound whose principal chain is identical to that of an unknown compound is enabled, thereby allowing analysis of an entire structure even if the entire structures of the known compound in database and that of the measured unknown compound are not identical. The MS n spectrum obtained in the MS n measurement of the unknown compound is compared with all the MS m spectra (m≧1) in the database regardless of MS n generation. In the MS n measurement of a series of related compounds including various types of different side chains of the same principal chain, such as in the case of biopolymers, it becomes possible to determine the structure of the principal chain using a database search even if the entire structure is not clear. And the estimation of the entire structure is made possible on the basis of the principal chain structure. | 7 |
FIELD OF THE INVENTION
The present invention pertains to general cleaning devices and more specifically to snake and grapple devices for retrieving and cleaning hair clogs from sanitary drainpipes in sewer lines.
BACKGROUND OF THE RELATED ART
Many devices exist in the field of the present invention that fulfill countless objectives with respect to cleaning sewer lines and drainpipes. None however fulfill the need for a safe and inexpensive device that is compact and effective in retrieving hair clogs from the upper portions of drainpipes found in the average home which are connected to sinks, tubs and showers.
A common problem that plagues people that use modern plumbing is the inevitable development of clogs that develop in the drainpipes connected to sinks, bathtubs and showers. These clogs may result from objects accidentally being dropped down a drain, but more typically are the result of a build-up of the soaps, oils, greases, hair and other organic material that is washed down the drain. Individuals skilled in the art and even the average homeowner are familiar with devices and methods used to try to open clogged drains. These include flexible plungers, metal plumber's snakes and numerous chemical and biological substances readily available in supermarkets and hardware stores. Plungers use air and water pressure to push and pull at the clog to dislodge it and allow it to freely flow out of the pipe and into the sewer system. Snakes are typically coils of flattened metal with a spiral wire on the end that are inserted into the drain to break through a clog by forcibly pushing, pulling and twisting to mechanically degrade the clog and allow it to flow freely into the sewer system. Chemical liquids and crystalline sodas chemically react with the clog, degrading or liquefying it until it flows freely into the sewer system.
These devices are often effective in freeing clogged drains but do not offer a consistent solution to opening clogged drains that are largely a result of an accumulation of hair that typically occurs in the trap and especially hair that becomes entangled in the drain pop-up lever arm assembly just below the drain pop-up in the opening of the drain. The current invention departs from concepts and designs of the prior art by embodying a device that is compact and capable of reliably and effectively removing such hair clogs from the upper portions of drains.
Each device of the current art is seen to be deficient in providing a solution for these upper-drain hair clogs upon examination. Plungers that utilize air or water pressure to dislodge clogs in drains do not reliably dislodge hair clogs because the pressurized air or water force is not great enough to break hair away from solid, fixed protrusions within the drainpipe. The hair that is entangled around a fixed object, primarily the drain pop-up lever arm, is a case in point. In addition, the hair that has become embedded in encrustment or build-up that has accumulated within the pipe in the drain trap or along the pipe wall are additional examples.
The common plumber's snake is another device of the prior art that is effective in breaking up drain clogs by repeated forcible insertion and retrieval of the device in the drain. These however have the drawbacks of being large and unwieldy for the average homeowner and often cannot be used for upper-drain clogs or those occurring from the drain opening to the trap because the drain opening around the peripheral area of the drain pop-up of a sink is not large enough to accommodate the metal spiral end of the snake. Smaller spiral-tipped sink snakes are available but still very unwieldy and not adept at snagging hair entangled around the drain pop-up lever arm. In addition, most of these devices are metal and subject to rust and corrosion. Specialized upper-drain snake devices do currently exist in the prior art, and in the marketplace, which are designed to be small enough to fit past the drain stopper in the drain opening of the typical sink. These devices each have disadvantages not present in the present invention. They are either unsafe for the user because of sharp edges, or have wire hooks which can get hooked on the pop-up lever arm, or they are not compact making them inconvenient to store or transport. These devices usually have length and cannot be coiled in a stationary fashion, which means a homeowner cannot store them in a drawer or the artisan cannot transport then in a toolbox due to their length. This is also a disadvantage in commercial sale since these devices cannot readily be packaged with the shelf size drain products that they work hand-in-hand with to provide a complete drain cleaning solution. These devices also have fewer hair-snagging elements than the present invention reducing their ability to snag, and hold, drain hair by comparison.
Homeowners typically resort to caustic chemical products to open clogged drains. These are often effective in chemically “burning away” drain clogs but have the disadvantages of being dangerous to people, pets and the environment. The caustic ingredients in these remedies often contain sodium hypochlorite (bleach), sodium hydroxide (lye) or acid. These chemicals are responsible for a multitude of human poisonings annually as well as eye, lung and flesh injuries from their use and existence in the household. These chemicals are readily available in most all grocery and hardware stores and are the easiest for the homeowner to use. Consequently, the large, cumulative volume that enters our sewage systems represents a hazard to the environment as the chemicals are not readily broken down in sewage treatment plants and flow out into the environment, adding unwanted and detrimental pollutants. In addition, the chemical solutions often flow by hair clogs that are wrapped around the drain pop-up lever arm and are suspended in the center of the drainpipe where the liquids cannot effectively work on them.
Biological drain opening products are also readily available to homeowners in stores and also represent an easy-to-use drain maintenance solution for homeowners. They typically come in a liquid or powder form that the homeowner simply washes down the drain similar to chemical products. These solutions have the benefit of ease of use without the danger of injury to people, pets and the environment. They work by utilizing natural and harmless live bacteria and enzymes that feed on the organic drain refuse and break it down to base elements in the same way that nature recycles refuse in the environment. These types of products hold out the hope of effective drain maintenance for the individual diligent in home maintenance and family safety. They also represent a benefit to society by replacing the chemicals that cause injury to people and damage to the environment. Unfortunately one drawback of biological products is that they are less effective for rapid treatment of hair-clogged drains. By not being able to readily free slow flowing drains due to hair clogs, biological drain products are less popular in the marketplace and consequently consumers more frequently purchase the dangerous and harmful chemical products to open drains to the detriment of society in general.
The present invention plays a vital role in solving the societal problem of using injurious caustic chemical drain opener products. It fulfills the need for a compact device for effectively clearing drain hair clogs. As a stand-alone device it fulfills the need for a safe, effective and easily stowable device for a homeowner to immediately and easily open up a slow-running, hair-clogged drain by retrieving the hair clogs that often occur in them.
The present invention also fills a void that currently exists in the prior art by representing a device that enhances and facilitates the use of people-friendly and environment-friendly biological drain maintenance products. By providing a compact and inexpensive device for clearing the hair clogs that biological products do not effectively eliminate, the present invention can readily be packaged with these products making them a more effective and attractive solution to opening clogged drains without the societal problem of exposing people to dangerous chemicals and harming the environment. Nothing found in the prior art or the marketplace combines the attributes of compactness, safety to the user and hair-snagging effectiveness like that of the present invention.
Consequently, the present invention represents a substantial departure from all the current concepts and designs in the prior art and includes many novel features and embodiments resulting in a new device for cleaning hair clogs from drains.
OBJECTS AND ADVANTAGES
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially those skilled in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
Accordingly, there are several objects and advantages of the present invention.
(a) It is an object of the present invention to provide a device for removing drain clogs that consist primarily of hair and other fibrous matter from the upper portions of drains from the drain opening to the trap where they typically form. (b) It is another object of the present invention to provide a new and novel device for removing hair and other fibrous clogs from the upper portions of drains which combines attributes in a fashion that has not previously been anticipated, rendered obvious or even been previously implied by any of the crowded prior art of drain cleaning devices. (c) It is also an object of the present invention to provide a device for removing hair and fibrous clogs that is easy and safe to use for both the average homeowner or artisan and which is inexpensive and affordable, and easily manufactured from existing products and materials. (d) It is another object of the present invention to provide a device for removing hair and fibrous clogs from a drain that does not harm the environment or present a health hazard in the household or for the artisan. (e) Another object of the present invention is to provide a device for removing hair and fibrous clogs that has a hair-snagging element at the distal end of an elongate shaft that is in the form of a pad which has width and thickness dimensions that allow it to fit into the drain opening through one of the four pie-shaped openings at the peripheral area of the drain pop-up stopper. This pad is not limited in shape but in the preferred embodiment of the device is manifested in the shape of a modified rectangle and made from readily available and inexpensive sections of the polymeric hook portion of hook-and-loop fastener material. The rectangular surface area of the hair-snagging pad has the end result of presenting the maximum number of hair-snagging hook elements on both the front and back side of the pad that the drain opening can accommodate. Hook-and-loop material is well known for its tenacious ability to snag and hold the loop portion of the fastener, providing the significant sheer strength or pull strength needed to pull loose and retrieve an entangled hair clog in a drain. Fibrous drain-hair clogs are similar in nature to this loop material and consequently also snag and hold tenaciously to the hair-snagging pad at the distal end of the present invention. The distinctive, rectangular shape of the pad has a wide sweeping range to snag hair when maneuvered and rotated within the drain. The hair-snagging pad in the preferred embodiment of the present invention utilizes the width of the flattened pad to present more hair-snagging hook elements against the clog and has an advantage over the prior art as stated in patent U.S. Pat. No. 5,836,032 issued to Hondo on Nov. 17, 1998. That device is not compact and is limited in the number of hooking elements presented to the clog since they are arranged radially around the elongate shaft which itself is limited in diameter to fit the largest circular dimension of the pie-shaped opening of the drain around the peripheral area of the drain pop-up stopper. The flattened hair-snagging pad of the present invention maximizes use of the widest lateral dimension of the drain opening rather than its smaller circular dimension. This consequently represents an advantage not contemplated in prior art providing a very effective device for removing hair clogs from drains while utilizing existing, inexpensive, tried-and-proven materials used in a new and novel way. (f) Another object of the present invention is to provide a device for removing hair and fibrous clogs that is compact by having a construction that is capable of easily being bent and formed into pocket-sized, fixed shapes such as a coil. This has a distinct advantage in the field of specialized, upper-drain snake devices of being more easily stored, transported and packaged for sale either alone, in multiple quantities, or in combination with other related drain care products. (g) It is another object of the present invention to provide a device for removing hair and fibrous clogs from a drain that can reduce the use of dangerous chemical drain openers and enhance the use of safe, biological drain cleaning products by being of such a compact size that it may be easily packaged with these safer types of off-the-shelf products. (h) Yet another object of the present invention in its preferred embodiment is to provide a device for removing hair and fibrous clogs that has all exposed parts made from plastic materials and not subject to rust or corrosion like metal snakes, and which is capable of either being cleaned and reused or simply disposed of due to its low cost. (i) Another object of the present invention is to provide a device for removing hair and fibrous clogs that due to its construction can be bent and remain fixed into many shapes. For the grasping, proximal end it may be formed for example into a circular, T-shaped or Z-shaped configuration to facilitate the pushing, pulling and rotating motion that is required to maneuver the hair-snagging distal end of the device into the drain and down to the fibrous clog. (j) Another object of the present invention is to provide a device for removing hair and fibrous clogs that has exterior surfaces made from plastic materials which are free of sharp edges making it safe for the untrained user or artisan. (k) Another object of the invention is to provide a device for removing hair and fibrous clogs that has effective hair-snagging ability without using metal hooks which tend to get snagged onto the drain pop-up apparatus within the drain when attempting to maneuver the device to snag hair clogs. Also, by utilizing polymeric hook-and-loop type material, the present invention is safer for the user than wire hook devices.
Further objects and advantages of the present invention will become apparent from a consideration of the drawings and ensuing description.
SUMMARY
The present invention is a device for quickly retrieving hair and other fibrous waste from a drain without dismantling the drain and without using dangerous chemicals in the drain and which comprises an elongate shaft, which flexes into fixed bent positions, having a proximal end portion for grasping and a distal end portion for insertion into a drain. In the preferred embodiment, the shaft is comprised of a plastic sheathed metal wire, which maintains a fixed position when bent allowing the device to be shaped into compact designs for ease of storage, transport and packaging as well as allowing various shapes to be bent at the proximal end to serve as a grasping and rotating handle. The device also includes a hair-snagging member which is securely attached at the distal end of the elongate shaft which is a flat, double-faced pad or pouch made from attaching two strips of the hook portion of common hook-and-loop material back-to-back. The resulting pad or pouch may be of various sizes and shapes but, in the preferred embodiment, has a predetermined length and width, which is determined by the longest lateral dimension of the pie-shaped opening created along the side of the drain pop-up stopper. By exploiting the thinner but wider dimension of the drain opening, the present invention departs from devices of the prior art which typically provide hooking materials disposed radially from the smaller dimensioned circular shaft of the device. This novel use of common hook-and-loop material in a double-sided, modified rectangular shape maximizes the hooking member surface area allowing over 300 hooking members per vertical inch of pad to be presented against the drain hair-clog and creating a larger sweep circumference within the drain when the shaft and pad are rotated via twisting the grasping proximal end of the shaft. This multitude of hooking members efficiently snag drain hair and fibrous material since those elements are very similar in nature to the loop portion of hook-and-loop material, creating entanglement on contact with the clog and having the increased holding strength that is necessary to withdraw drain hair and fibrous matter which becomes tenaciously entangled around the drain pop-up mechanism and in the drain trap.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description. The description makes reference to the attached drawings wherein:
FIG. 1A is a perspective view of the preferred embodiment of this invention.
FIG. 1B is a perspective view of the preferred embodiment bent into a fixed coil shape showing its compact handheld size for storage and packaging.
FIGS. 1C-1E are top elevations showing the method of use of the preferred embodiment of FIG. 1A of the invention. The embodiments of FIGS. 2 , 3 , 4 A and 5 A would be operated in a similar fashion.
FIG. 1F is a perspective top view of a typical drain opening and pop-up stopper showing the pie-shaped drain openings and the optimum insertion angle for the invention.
FIG. 1G is a side sectional view of a typical drain and trap showing where hair clogs typically accumulate.
FIG. 1H is a cross-sectional close-up view of the elongated shaft of the preferred embodiment of this invention.
FIG. 1J is a close-up view of the plastic plug, which is inserted in the proximal end of the sheath covering of the elongated shaft of the preferred embodiment of this invention.
FIG. 1K is a close-up side elevation view of the hair-snagging pad showing the hooking members disposed at the distal end of the elongated shaft of all the embodiments of this invention.
FIG. 1L is a perspective view of another embodiment of this invention, which shows how the device may be made with an all-plastic shaft.
FIG. 2 is a perspective view of another embodiment of this invention, which shows how a quick-release catch mechanism is used to create a removable and disposable hair-snagging pad.
FIG. 3 is a perspective view of another very basic embodiment of this invention, which is simply a wire with a hair-snagging pad at the end.
FIG. 4A is a perspective view of yet another embodiment of this invention in which the basic wire version of FIG. 3 has a plastic-coated wire instead of a bare wire and the grasping end has a circular bend.
FIG. 4B is a close-up view of the proximal, grasping end of the embodiment shown in FIG. 4A , showing the method of operation utilizing the circular bend as a finger spin ring.
FIG. 5A is a perspective view of yet another embodiment of this invention showing the hair-snagging pad and wire shaft as disposable members with a removable handle.
FIG. 5B is a close-up end view of the embodiment of FIG. 5A showing the method of inserting and removing the disposable wire with pad member into the removable handle.
FIG. 5C is a close-up end view of the removable handle of the embodiment shown in FIG. 5A displaying the opening for inserting the wire shaft, and also showing the release button used for inserting and removing the wire shaft with pad.
FIG. 5D also shows the embodiment of 5 A but as a close-up sectional view of the end of the removable handle revealing the release mechanism inside in the locked position when the release button is not pushed.
FIG. 5E is also a close-up end view of the removable handle embodiment of FIG. 5A except with the release button pushed into the release position.
DRAWINGS—REFERENCE NUMERALS
10 shaft
12 pad or pouch
14 wire
16 sheath
18 plug
22 female catch fastener
24 male catch fastener
26 drain opening
28 drain pop-up stopper
30 pie-shaped opening
32 insertion angle
34 pop-up lever arm
36 hair clog
38 hooking members
40 removable handle
42 handle release mechanism
46 finger spin ring
48 release button
52 wire lap cover
54 lock slot
56 loop bend
58 grasping member
60 coiling fastener pad
62 coiling slot
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention for removing hair and fibrous clogs from drainpipes is best understood by reference to the attached drawings.
Preferred Embodiment— FIG. 1A
FIG. 1A shows a perspective view of the preferred embodiment of the invention. The shaft 10 of the device consists of a plastic sheath 16 made from common 3/16″ OD PVC plastic tubing with a 90 Shore A durometer hardness with a #16 galvanized wire 14 inserted inside. FIG. 1H is a sectional view of the shaft 10 perpendicular to the longitudinal axis of the shaft 10 . The shaft 10 may be of any length but in the preferred embodiment is approximately 61 cm or 24 inches to reach past the typical drain trap. The wire 14 is sealed inside the sheath 16 with a readily available plastic, barbed plug 18 in FIG. 1J that is inserted into the grasping, proximal end of the shaft. The wire 14 shown if FIG. 1H gives the device enough rigidity for pushing into drains. The distal end of the sheath 16 is heat-sealed into a flattened, bell shape (not shown) and inserted into the hair-snagging pad 12 shown in FIG. 1A . The hair-snagging pad 12 consists of two matching pieces of the hook portion of common hook-and-loop fastener material. The two pieces are fastened at the edges back-to-back into a pad or pouch 12 . The two pieces of hook material may be thermally attached, attached with adhesive or mechanically attached together with eyelets, rivets or similar fasteners (not shown). The flattened, distal end of sheath 16 is inserted into the pouch 12 and the pouch 12 is then sealed around the flattened, bell-shaped distal end (not shown) of the sheath 16 resulting in a pad 12 . The resulting pad 12 has hooking members 38 on both exposed, substantially flat surfaces of the pad 12 as seen in the side elevation view in FIG. 1K . The pad 12 may be many different shapes, colors and sizes but in the preferred embodiment is 15.88 mm by 25.4 mm or ⅝″ by 1″ and approximately shaped into a modified rectangle with approximately 300 hooking members 38 total on both sides of the pad 12 . This width dimension is maximized to fit the typical sink drain opening 26 which is often restricted by a pop-up stopper 28 as shown in FIGS. 1F and 1G , which is installed at the opening of the drain. As seen in FIGS. 1F and 1G , the pop-up 28 body segments the drain opening into 4 smaller, pie-shaped openings 30 . By designing the invention with a substantially flat, rectangular shaped snagging pad 12 , it is able to slide past the pop-up stopper 28 at an oblique insertion angle 32 with respect to the circumference of the drain opening as shown by the diagram in FIG. 1F .
Additional Embodiments— FIG. 1L
FIG. 1L shows another, simplified embodiment of the present invention. This version maintains the novel features of being a compact device, and having a shaft 10 capable of being coiled along with a hair-snagging pad 12 , but is made even more inexpensively by having a molded plastic shaft 10 with grasping member 58 located at the proximal, grasping end, and the same unique hair-snagging pad 12 disposed at the distal end of the device. The hair-snagging pad 12 consists of two matching pieces of the hook portion of common hook-and-loop fastener material. The two pieces are fastened at the edges back-to-back into a pad or pouch 12 . The two pieces of hook material may be thermally attached, attached with adhesive or mechanically attached together with eyelets, rivets or similar fasteners (not shown). The molded plastic shaft has a T-shape (not shown) at the distal end, which is inserted into the hair-snagging pad 12 . This T-shape provides pull-out resistance from within the sealed pad or pouch 12 . The device in this embodiment is designed to be disposable after use and may be purchased economically in quantities for the home, institutional, or artisan user. The device as represented in this embodiment does not have a metal or wire core to maintain the fixed, coiled position necessary for ease of storage, transport and packaging. Consequently, it may also have a piece of the loop portion of common hook-and-loop material attached to the grasping member 58 to create a coiling fastener pad 60 such that when coiled by inserting through the grasping member 58 , and specifically through the coiling slot 62 , after 2 loops, the pad 12 wraps around and sticks to the attached piece of loop material and the device maintains a coiled configuration. The invention as represented in this embodiment may also be made from metal, however only for high volume, non-consumer users who are properly equipped with protective gloves due to the possibility of sharp edges and injury to the user.
Additional Embodiments— FIG. 2
FIG. 2 shows another embodiment of the present invention. This variation of the inventive device maintains the novel features of the preferred embodiment including a substantially flat, hair-snagging pad 12 and also a flexible shaft 10 which may be bent into compact fixed positions such as a pocket-sized coil. In this embodiment, the shaft 10 is made from molded plastic which may or may not have a wire core, and the hair-snagging pad 12 is sealed around the distal end of the male member of a catch mechanism 24 resulting in a pad 12 and catch 24 combined unit. The proximal end of the male catch 24 is snapped into a mating female member of the catch mechanism 22 which is molded into or attached to the distal end of the shaft 10 of the invention. The purpose of the mating catch mechanisms 22 and 24 is to provide a device for cleaning hair-clogs 36 ( FIG. 1G ) and other fibrous debris from a drain in which the hair-snagging pad 12 may be used and discarded with the retrieved debris. By releasing the catch 24 , the combined pad 12 and male catch 24 unit are freed from the device for disposal and ready for another new pad 12 and catch 24 unit to be snapped into place. It will be apparent after examining the drawing in FIG. 2 that equivalent functionality may easily be envisioned and implemented to serve the same purpose for the female catch 22 and male catch 24 . The depiction of these in the drawings shows a common buckle type snap-fit mechanism for illustrative purposes only to display the principle of the removable hair-snagging pad 12 , and are not intended to limit the invention to the exact construction and operation shown. It is the intent of the present invention to encompass other equivalent functioning embodiments of the female catch 22 and male catch 24 that satisfy the purpose of their functionality of easy removal of the pad 12 within the context of the present, novel invention.
Additional Embodiments— FIG. 3
FIG. 3 shows an additional embodiment of the invention. This embodiment is a stripped down version of the preferred embodiment, which may be manufactured even less expensively and may be desirable to the institutional user with many drains or the artisan who cleans drains professionally and has more interest in pure functionality than visual appeal. This embodiment consists of simply a #12, #14 or #16 size wire 14 or a plastic coated wire 14 with the attached hair-snagging pad 12 . The distal end of the wire 14 is bent into some shape that has shoulders perpendicular to the wire 10 shaft, such as an oblong O-shape or a T-shape (not shown) and is then sealed inside the pad 12 pouch thermally, mechanically or with adhesives. By bending the end of wire 14 , a shoulder is created which is perpendicular to the longitudinal axis of the wire 14 and which creates pull-out resistance of the wire 14 from the pouch 12 . The proximal end of the wire 14 is left unbent for the user to insert into a drill or to manually bend into various grasping shapes such as a crank, O-shape or T-shape.
Additional Embodiments FIGS. 4A-4B
The embodiment of the invention shown in FIG. 4A is the same as described above in FIG. 3 except that the proximal grasping end of the wire 14 shaft is bent into a finger spin ring 46 loop which may act either as a grasping handle or a means to rotate the shaft by insertion of the finger in a stirring motion as noted below in the operational description of this embodiment and depicted in FIG. 4B . The finger spin ring 46 is created by bending wire 14 on the proximal end into an O-shape while leaving a length of extra wire at the proximal end for twisting back around the wire 14 shaft at the base of the finger spin ring 46 and then covering the lapped extra length of wire 14 (not shown) and wire 14 shaft with a wire lap cover 52 made from a piece of heat-shrink PVC plastic approximately 3.81 cm or 1.5 inches long.
Additional Embodiments— FIGS. 5A-5E
FIGS. 5A-5E show another embodiment of the invention. In this form, the embodiment of FIG. 4 is taken one additional step by adding a removable handle 40 to the device as shown in FIG. 5A and utilizing a loop bend 56 as seen in FIG. 5B at the proximal end of the wire 14 for preventing the wire 14 with pad 12 combined member from pulling out of the handle 40 . The wire 14 may also be plastic coated. Once again this embodiment is targeted toward the professional artisan or institutional user who desires the same functionality of the preferred embodiment of the device, but regards per-use, reduced cost and utility of greatest importance. This embodiment retains the novel and effective double-sided snagging pad 12 and bendable memory of the wire 14 to coil the replaceable wire 14 with pad 12 combined members into a compact size for portability and packaging along with the handle 40 . The waterproof PVC sheath 16 and plug 18 of the preferred embodiment are not found in this version of the device since it will not optionally be cleaned and reused, but rather the wire 14 with pad 12 will simply be disposed of after use. The removable handle 40 is preferably made of molded plastic with a handle release mechanism 42 as shown in FIGS. 5C-5E into which the wire 14 is slid and automatically locked in place. The wire 14 receiving end of the handle 40 has a vertical lock slot 54 as viewed in FIG. 5C into which the looped end of the wire 14 is inserted after pushing release button 48 . FIG. 5C shows and end view of the handle 40 with the release button 48 in the out position. FIG. 5D shows a sectional end view of the handle 40 revealing the internal handle release mechanism 42 with the release button 48 in the out position. In this locked position, the loop bend 56 shown in FIG. 5B is unable to pull out through the smaller horizontal opening of the lock slot 54 . FIG. 5E is a sectional view of the handle 40 with the release button 48 in the pushed-in position. With the release button 48 pushed in as shown in FIG. 5E , the vertical opening of the lock slot 54 is revealed, allowing the loop bend 56 end portion of wire 14 to be inserted or withdrawn from the handle 40 . The wire 14 with pad 12 can be discarded after use.
The loop bend 56 in the wire 14 shown in FIG. 5B prevents the wire 14 shaft from spinning inside the handle 40 upon rotation of the device via the handle 40 . It will be apparent after examining the drawing in FIG. 5 that equivalent functionality may easily be envisioned and implemented to serve the same purpose for the removable handle 40 and handle release mechanism 42 . The depiction of these in the drawings are for illustrative purposes only to show the principle of the removable handle 40 and handle release mechanism 42 and not intended to limit the invention to the exact construction and operation shown. It is the intent of the present invention to encompass other equivalent functioning embodiments of the handle 40 and handle release mechanism 42 that satisfy the purpose of their functionality of a removable handle 40 and handle release mechanism 42 within the context of the present, novel invention.
Operation Common to All Embodiments
The device in its various embodiments as illustrated in FIGS. 1A , 1 L, 2 , 3 , 4 A and 5 A is used to retrieve hair-clogs 36 shown in FIG. 1G and other fibrous debris from the upper portions of drains from the drain opening to the U-shaped trap. The flexible shaft 10 allows the device to be bent into many shapes that aid in grasping, pushing, pulling and rotating the device to navigate the drainpipe and snag clogs. For example, if the device comes to the user packaged in a coil, the user may simply uncoil the needed length to reach the hair-clog and grasp the remaining O-shaped uncoiled shaft as a handle as viewed in FIGS. 1C-1D . The proximal end of the shaft may also be bent into a T-shape handle for the same grasping convenience. A third option might be to bend the grasping proximal end into a Z-shape crank (not shown) and use both hands to crank the device, rotating the pad 12 within the drain like a rectangular paddle, sweeping and entangling the drain hair and other fibrous clogs. The 300 odd hooking members 38 on both sides of the hair-snagging pad 12 will aggressively entangle and hold the hair for retrieval of the clog.
Additional Operation of Embodiment in FIG. 1L
The embodiment of the device as represented in FIG. 1L operates in a very similar fashion to the other embodiments. The distal end of the device with the hair-snagging pad 12 is inserted into the drain and manipulated in an up and down or rotating motion to snag hair clogs 36 ( FIG. 1G ) suspended over the drain pop-up lever arm 34 or in the drain trap. This version of the device is simply held by the enlarged, molded plastic handle grasping member 58 located at the proximal end of the device while manipulating the device, or else the user's finger may be inserted in the hole of the grasping member 58 for pulling or rotation of the device.
Additional Operation of Embodiment in FIG. 2
The embodiment of the device as shown in FIG. 2 operates significantly the same as the embodiments illustrated in FIGS. 1A , 3 , 4 A and 5 A as noted above with the exception that this embodiment has a removable pad 12 with male catch 24 . After inserting, maneuvering, and withdrawing the device from the drain as stated above under operation common to embodiments in FIGS. 1A , 2 , 3 , 4 A and 5 A, the user simply pinches together the release arms of the male catch 24 to free the catch 24 and pad 12 for disposal along with the hair and fibrous waste retrieved from the drain. The user can then simply snap in a new, clean catch 24 with pad 12 unit. The shaft 10 with attached female catch 22 mechanism is purchased only once so that the user may buy the smaller and less expensive male catch 24 with pad 12 units in quantity for future drain maintenance.
Additional Operation of Embodiment in FIG. 3
In addition to the functionality described above under operation common to embodiments in FIGS. 1A , 2 , 3 , 4 A and 5 A, the embodiment of the invention as shown in FIG. 3 is designed to be purchased in quantities and disposable after each use. An optional mode of operation for this embodiment is to insert the proximal end of wire 14 into an electric drill for creating an automatic rotation motion of the hair-snagging pad 12 in the drain.
Additional Operation of Embodiment in FIG. 4A
In addition to the functionality described above under operation common to embodiments in FIGS. 1A , 2 , 3 , 4 A and 5 A, the embodiment of the invention as shown in FIGS. 4A and 4B is designed to be purchased in quantities and disposable after each use. An optional mode of operation for this embodiment is to rotate the shaft 10 with pad 12 by use of the finger spin ring 46 . This allows the user to grasp the wire 14 lightly in one hand while inserting the index finger of the other hand into the ring 46 and rotating the whole device with a stirring motion of the finger along the inside surface of the ring 46 as shown in FIG. 4B .
Operation of Embodiment in FIG. 5A
The embodiment of the device as shown in FIG. 5A is used to retrieve hair-clogs and other fibrous debris from the upper portions of drains from the drain opening to the U-shaped trap. As shown in FIG. 5A , this embodiment of the invention has a removable handle 40 that aids in grasping, pushing, pulling and rotating the device to navigate the drainpipe and snag clogs. The wire 14 and snagging pad 12 are slid into the removable handle 40 and locked into place with the handle release mechanism 42 shown in FIGS. 5D-5E . The handle is then grasped for the inserting, pushing and pulling of the device required to navigate the drain and snag and remove hair and other fibrous clogs. The rotating pad 12 within the drain acts like a rectangular paddle, sweeping and entangling the drain hair and other fibrous clogs encountered within the drainpipe. The 300 odd hooking members 38 as shown in FIG. 1K , on both sides of the hair-snagging pad 12 will aggressively entangle and hold the hair for retrieval of the clog. After use, the release button 48 on the handle 40 is pressed allowing the wire 14 with attached pad 12 to slide out and be thrown in the trash with the accompanying hair and other fibrous waste that is snagged. The user is then ready to insert a new, clean wire 14 with pad 12 into the reusable handle 40 . The handle is purchased only once and then the user need only buy the replacement wire 14 with attached pad 12 units in quantities for an inexpensive and convenient way to maintain drains on a regular basis. The operation of the handle release mechanism 42 will be apparent from viewing the drawings in FIGS. 5C-5E .
CONCLUSION
As can be seen from reviewing the drawings and descriptions above, the present invention in its various embodiments represent a new and novel device for retrieving hair-clogs and other fibrous debris from the upper portions of drains in the common household. Its advantages include:
Being hand-held in size due to its coiling capability making it compact for packaging, storing and transporting Unique hair-snagging surfaces made from the hook portion of common hook-and-loop material which maximizes the number of hooking members due to its 2-sided substantially rectangular-shaped pad configuration Safe for the user since it has no sharp edges or metal hooks Safe for people, pets and the environment by opening hair-clogged drains without the use of caustic chemical drain openers Compact enough to be packaged with off-the-shelf biological, drain-opener products creating a totally new combined product offering that is a complete drain maintenance solution without the environmental and safety issues of chemical drain products Inexpensive to manufacture from commonly available materials Inexpensive to buy due to low cost of manufacture Made from corrosion-resistance materials
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A compact, smooth surfaced, flexible and formable, elongate apparatus that has a hair-clog snagging end portion for insertion into drains for snagging and removing the common hair clogs that exist in the upper portion of drains typically around the drain pop-up mechanism and drain trap. The elongate shaft ( 10 ) may be bent along its complete length into any shape and remain fixed in that shape to accommodate compact storage as well as forming a grasping and twisting handle for the shaft while it is in the drain or bending the hair-snagging end of the shaft for easier insertion and navigation within the drain. The hair-clog snagging portion, which is at the distal end of the shaft, is in the form of a pad ( 12 ), which maximizes the surface area of hair hooking members ( 38 ). The hair-snagging pad consists of the hook portion hook-and-loop fasteners and contains a multitude of miniature, hook formed, polymeric elements which aggressively entangle hair-clogs for quick retrieval from the drain without dismantling the drain and without using dangerous chemicals in the drain. | 4 |
FIELD OF INVENTION
This invention deals with the field of spectroscopy and specifically with the application of spectroscopy to measurement of circularly polarized light. More specifically it deals with optical elements that can be inserted into the optical path of either the exciting light or into the optical path of the transmitted or scattered light.
All measurements of various forms of optical activity rely on a small difference in the interaction of the right and left circularly polarized (hereinafter CP) or chiral light with a chiral sample. Typically, the chiral sample consists of molecules that are chiral, i.e., molecules that have non-superimposable mirror images of each other, like a person's left and right hand. There are three areas where this interaction manifests itself in a degree that can be measured. In optically active scattering, a small difference in the intensity for the left or right CP of the scattered light from the sample when the sample is excited with left and right CP light. Alternatively, when linearly polarized light (not left and right CP light) is used to excite a chiral sample, small differences in left and right CP scattered light can be detected. Finally, in circular dichroism a small transmission difference for the right and left CP light that passes through the sample and is absorbed by the sample is measured.
The most significant problem in all three types of measurements is the occurrence of small spurious spectral intensity differences, or offsets, not due to the optically active (chiral) nature of the sample itself but rather due to the optical imperfections in the measuring instrument.
The current invention provides a means to reduce such offsets to negligible levels in the measurement of optically active light scattering and circular dichroism.
DESCRIPTION OF THE PRIOR ART
Small intensity differences in the CP measurements are typically detected by modulating the polarization of the probing light, or the polarization analyzing properties of the detection system, or both, between left and right CP, synchronized with the routing of the acquired data into a right and left detection channel. The left and right detection channel data can be electronically manipulated to give a spectral scan of the sample that incorporates only the difference in the left and right CP light detected. In principle, very small intensity differences in the CP light can be recovered and analyzed. This requires the transmission characteristics of the measuring instrument to be identical for both the right and the left CP light modulation period, except for the creation or selective detection of the right or left CP light.
Previous published approaches designed to achieve the above condition are static in the sense that they try to achieve offset free operation of the instrument at all times. They often use optics of extreme precision and rely on tight and stable control of the momentary polarization state of the light. Small persisting errors at one place in the optical train of an instrument or typically compensated for by a deliberate, judicious introduction of canceling errors elsewhere. Examples are the adjustment of the voltage of electro-optic modulators, or changing the angular orientation of static depolarizing devices. Such tedious and sometimes arbitrary procedures in order to achieve the desired flat instrumental baseline are often required for each sample measured.
SUMMARY OF THE INVENTION
The present invention uses a time averaged and automatic offset cancellation to achieve the desired flat instrumental baseline. The invention uses the selective multiple inter-conversion of polarization states of coherent and incoherent light to achieve a time-averaged offset-free measurement of optically active scattering or circular dichroism. The polarization conversion is applied separately in the light by individual optical elements but in a concerted manner to the incident light used to excite scattering or absorption in the sample. In the same manner, the invention is applied to the light scattered or transmitted by the sample to get a flat baseline.
An object of the invention is to achieve an offset-free circular dichroism instrument in a time averaged manner.
Another object of the invention is to achieve an offset-free optically active light scattering instrument in a time averaged manner.
Both these objectives are obtained by the invention.
BRIEF DESCRIPTIONS OF THE DRAWINGS
As part of the specification, the drawings illustrate principles of the present invention and together with the description serve to explain the invention.
FIG. 1 is a schematic representation of a CP light generator and a pair of half-wave plates that are critical to the understanding of the invention.
FIG. 2 is a schematic representation showing the wave plates critical to the invention with a circular polarization analyzer.
FIG. 3 is a schematic representation showing the wave plates that are critical to the invention with the addition of an additional wave plate that enhances the invention.
FIG. 4 is a schematic of the invention incorporated into the optical path of a scattered circular polarization Raman optically activity scattering instrument.
FIG. 5 shows the spectra of a compound using the invention in an instrument as described in FIG. 4 .
FIG. 6 shows additional spectra of a compound using the invention in an instrument as described in FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
The polarized light transformed by the invention by itself does not have, and does not need to have, ideal polarization properties with respect to the intended measurement. The time-averaged cancellation of measurements performed with transformed light and untransformed light over a finite interval of time eliminates offsets. During the process, polarization and intensity information on optically active scattering is preserved.
One of the properties imparted to a beam of light by the invention is a time-averaged isotropic superposition of the linear polarization states of the beam of light. If a polarization analyzer was placed into a beam of light after the beam had passed through the invention, the time-averaged amount of light for any azimuthal orientation about the direction the beam of light propagates in would be equal.
Another property imparted on a beam of light that has been modulated between right and left CP light is the precise equilibration on the amount of right CP light in the right modulation period with the amount of left CP light in the left modulation period. The invention also achieves the precise equilibration of the total light intensities in the two modulation periods.
Another property imparted to the beam of light, where no modulation between right and left CP states is performed, is the extremely precise time-averaged equilibration of the amounts of right and left CP light that the beam contains. This property is effectively imparted to the light beam by the invention and is useful for the incident light beam hitting the sample.
Another property conferred to the scattered or transmitted beam of light where the beam is circular polarization analyzed is the conversion of the beam's circular component from right to left circular and from left to right circular. The invention presents the right CP transmitted or scattered light first as right CP light and next as left CP light to the circular polarization analyzer. The reciprocal sequence presents the left CP scattered or transmitted light to the analyzer first as left and then as right CP light.
Devices that can effect the required transformations of the polarization states of the light are optical retardation plates based on birefringence or on Fresnel reflection. The present invention uses half-wave and quarter wave retardation plates that are well known in the prior art. A half-wave retardation plate has two effects on the beam of light that are important to the invention. First, the half-wave plate will convert right CP light into left CP light and left CP light into right CP light. Second, the half-wave plate converts one linearly polarization state into another with the resulting plane of polarization rotated by twice the angle between the plane of polarization of the incident light and the fast axis of retardation. Thus, if the incident light has a plane of polarization of zero degrees and the fast axis of retardation of the half-wave plate is at ten degrees, the beam of light exiting from the half-wave plate will have a plane of polarization of twenty degrees.
A quarter-wave retardation plate also has two effects on the light that are important to the invention. First, the quarter wave plate converts CP light into linearly polarized light with a plane of polarization oriented at +45 degrees or −45 degrees to the fast axis of the retardation. Second, the quarter-wave plate can convert linearly polarized light that is oriented at +45 degrees or −45 degrees to the retardation axis of the quarter-wave plate to right or left CP light. All this is well known to those experienced in the art of making spectrometers for various functions.
The half-wave or the quarter-wave retardation plate based on birefringence performs the above functions precisely only at a specific wavelength of incident light. At neighboring wavelengths close to the exact half-wave or quarter-wave wavelength of ideal operation, a retardation plate acts to nearly the same extent as that of an exact half-wave or quarter-wave retardation plate at that particular wavelength. The effectiveness of the invention described herein is such that a range of wavelengths covering approximately plus or minus ten percent of the exact wavelength of ideal operation is sufficient to time-average offsets to below negligible levels if appropriate retardation plates are used. Approximately twice this range of wavelengths can be covered by repeated application of the invention with two half-wave or quarter-wave plates that have an overlapping central wavelength differing by approximately 20 percent. Outside this approximate range, achromatic retardation plates are required to effect polarization cancellation of offsets across a broader region of the spectrum.
FIG. 1 shows a schematic diagram of the invention. Initially the beam of light 1 generated by a light source like a laser passes through the basic switchable circular polarization generator 2 . The circular polarization generator 2 can be any of the known type of devices used to alternately generate left and right CP light. The light generated from such a device is sometimes called elliptically polarized light because it consists of a large circular component and a small linear component of different size and orientation for the two modulation periods. So the light coming from the polarization state generator 2 can be considered as largely left and right CP light with a small linearly polarized component.
Next the light passes through a rotating half-wave plate 4 . This rotating half-wave plate is called the linear rotator, and its purpose is to systematically rotate the orientation of the plane of polarization of the linear component of the light evenly in time over all possible orientations. Thus to use our example from above, if the initial plane of the polarized light coming from the polarization state generator 2 is zero degrees and the retardation axis of the half-wave plate 4 at this instant in time is ten degrees, then the plane of polarization of the light coming out of the linear rotator is twenty degrees. In the next instant of time, the plane of polarization of the linear component coming from the polarization state generator 2 is still zero degrees, and the linear rotator 4 has rotated the retardation axis to eleven degrees, the plane of polarization of the light exiting the linear rotator is twenty-two degrees. In time, the linear rotator will rotate the linear component evenly over all orientations.
An undesired effect of the linear rotator 4 is to convert the left CP light into right CP light and the right CP light into left CP light. This problem can be corrected for by simply interchanging the registration of the right and left modulation periods in the data collection channels of the data collector.
After the light leaves the linear rotator, it strikes another half-wave plate called the circularity converter 6 that can move in and out of the optical path. The circularity converter changes left CP light into right CP and vice versa. If, as is common, a difference exists in the intensity of the circular polarized light between the left and the right modulation period with the circularity converter out of the optical path, it will also exist with the circularity converter in the optical path. If the circularity converter is in the optical path, the left and right CP light will be interchanged. If, over a period of time, the circularity converter is repeatedly moved into and out of the optical path, the relative intensity differences of the left and right CP components of the light will be equal when they are time averaged.
A preferred arrangement of the invention according to FIG. 1 uses a rotating circularity converter 6 with the direction of rotation, speed of rotation and phase chosen to be optimized with the light produced by the linear rotator 4 , A strongly preferred embodiment of the rotating circularity converter consists of synchronized quarter wave plates rotating in the same direction first with their fast axes aligned and then with the fast axis of one plate aligned with the slow axis of the second plate. With the fast axes aligned, the circularity converter would be a half-wave plate and with the fast axis of one plate aligned with the slow axis of the second plate, it would be a zero-wave plate thus imparting no change to the left and right CP light. There are also non-moving embodiments of circularity converters that use stress or electrically induced variable retardation.
FIG. 2 is a schematic diagram of the invention as it is configured for analysis of left and right CP light. After the light 1 leaves the sample, it interacts first with the rotating half-wave plate, the linear rotator 4 . The effect of the linear rotator on the light is the same as described above. The linear polarized component of the light that passes through the linear rotator 4 is rotated evenly in time so that there is no time-averaged orientation to the linearly polarized component of the light. Thus there is a time-averaged absence of sensitivity to the size and direction of the linear polarization components of the light. Again the left and right CP light are converted to right and left CP light respectively, but this is inconsequential and can be corrected for by interchanging the registration of the left and right modulation periods in the detector.
Just as in the previous description, the action of the circularity converter 6 that moves into and out of the light path is to inter-convert the left and right CP light that passes through it. The inter-conversion allows for the precisely equal transmission characteristics for the right and left CP components of the light.
The basic circularity polarization analyzer 8 can be any of the well known kind of devices used to alternately, or simultaneously, determine the size of the right and left CP component of the light incident on them. Practical devices inevitably show a slight sensitivity in their transmission characteristics to the direction of the axes of the polarized light being analyzed. Mechanically, electrically, or other switchable devices, which alternately direct the left and right CP incident light into the same detection channel, can also show different transmission characteristics for the two switching positions. In the present invention, the action of the circularity converter 6 means that any offset that may be in the analyzer for the difference between right and left CP light will cancel. Thus by moving the circularity converter into and out of the light path, offsets that would only affect the left CP light will now affect the right CP light in exactly the same manner.
The preferred embodiment of the invention in FIG. 2 uses a rotating circularity converter 6 with its direction of rotation, speed of rotation, and phase of rotation chosen to be optimized with the effect produced by the linear rotator 4 . Practical devices are the same as described for FIG. 1 above.
FIG. 3 is a schematic diagram of the invention which an additional element has been added. The additional element is a rotating quarter-wave plate 10 , the circular rotator, which is placed into the optical path between the linear rotator 4 and the circularity converter 6 . The effect of the circular rotator on the incident light is to convert a net right or left CP light into a rotating linearly polarized component with the same direction and velocity of rotation as the circular rotator 10 . The effect on a linear component of the light is to convert it alternately into right and left CP light, with an intermediate passing through elliptical and linear polarization states.
It is an important aspect of the arrangement of FIG. 3 , in order to achieve the level of precision required in optically active scattering or transmission, with moderate speeds of rotation, that the velocity and phase of the rotation of the linear rotator 4 and of the circular rotator 10 must be locked to the instrumental data acquisition cycle. The rotations must also be synchronized to each other. In particular, the absolute and relative speed of rotation of the linear rotator 4 and the circular rotator 10 must take into account a time-varying character of the amount and polarization of the light incident on the arrangement. For very high rotation speeds, the synchronization requirements can be relaxed. Sufficient averaging can be achieved under this condition by proper de-synchronization of the two rotation speeds.
A preferred embodiment uses counter-rotating plates 4 and 10 , In the case of static elliptical polarized incident light, the preferred speed of rotation of the circular rotator 10 is twice the speed of rotation of the linear rotator 4 .
The function of the circularity converter 6 , that is moved into and out of the light path, is to further equilibrate the right and left CP light produced by the action of the linear rotator and the circular rotator. The effect of the circularity converter on the various lights has been described above.
The effect of the optical elements as shown in FIG. 3 and the above explanation on an arbitrarily polarized light beam is to remove, in a time averaged manner to a very high degree of precision, all traces of linear and circular bias on the light beam. At any instance the components of the light beam may have offsets, but if the measurements are conducted over a period of many rotations of the components of the invention, all the offsets go to zero. Any optical device that can completely scramble the polarization states of the light beam can achieve a similar result. Such a device is the fiber-squeezer-based dynamic polarization scrambler. By contrast, the effect of the optical elements depicted in FIG. 1 and FIG. 2 on arbitrarily polarized left and right CP light beams is first to time average to zero all linear polarization components. Second, as depicted in FIG. 1 , it is to remove any imbalance in the amount of left and right CP light incident on the sample generated by the circular polarization generator 2 . Third, as depicted in FIG. 3 , it is to remove any imbalance in the response of the circular analyzer, or subsequent optics, to left versus right CP light. Thus, the optical elements depicted in FIGS. 1 and 2 represent the essence of the invention which does not scramble the polarization states of the light, but rather they transform the polarization states of light in a controlled time-average manner. This controlled manner then yields the precise measurement of the differential effect a chiral sample has on the scattering or absorption of pure left and right CP light without interfering intensity offsets from the instrumental optical components.
The precision of the retardation of the half-wave plate in the linear rotator 4 and the circular converter does not need to be extraordinarily high. Time-average rotation to zero of small linear components is important but not required to be absolutely perfect. Balancing the circularity and total intensity of the exciting light, on the other hand, does need to be nearly perfect. If the correction achieved with a single circularity converter 6 is insufficient, a second circularity converter could be installed in the optical path and operate just like the first one. If necessary, this operation could be repeated a third time and fourth time etc. Arbitrarily precise balancing of the relative circular content of the light can be achieved this way.
EXAMPLE
Optical Offset Elimination in Collinear Scattered Circular Polarization Raman Optical Activity Scattering (SCP-ROA)
Scattered circular polarization Raman optical activity scattering (SCP-ROA) is defined as the difference in the Raman scattered light intensity from a sample of chiral molecules for alternately or simultaneously analyzed right and left CP scattered Raman light. The incident light is in a fixed unpolarized state. FIG. 4 is a schematic of how the invention would be used in SCP-ROA. Forward scattering is used in this example, but identical considerations apply to other scattering geometry.
FIG. 4 is a schematic of the device that achieves the balancing of the content of the left and right CP light to a high level of precision that is required for this technique. The arrangement in FIG. 4 achieves this level of precision, in a time-averaged fashion, without any need for the precise adjustment even for incident light having a circularity content of one percent or more. If high quality linear polarized light is available from the polarization modulator 12 , then it is possible to omit the circular rotator 10 of FIG. 3 from the light that is exciting the sample. As shown above the invention leads to the complete equilibration, in a time averaged fashion, of all the linear and circular components of the light prior to the focusing lens 14 and the sample 16 . So essentially the light has no polarization characteristics in a time averaged fashion.
The polarization analyzing section for the scattered light uses the linear rotator 4 ′ and the circularity converter 6 ′ to correct offsets created by the basic circular polarization analyzer. The polarization analyzer is assumed to consist of an electrically switchable liquid crystal retarder 24 and a linear polarization analyzer 22 . The light transmission of liquid crystal retarders depends of their switching position. Differences can reach 2 parts in 1000. Such devices, in spite of their otherwise desirable characteristics, have, therefore, not been applicable to the precise measurement of the optical activity phenomena. The use of the circularity converter makes it possible for the first time to use the liquid crystal retarder.
FIG. 5 is an example of the effectiveness of the invention for the particular case of SCP-ROA scattering of the optically active compound (−)-alpha-phenylethylamine. The measurement conditions are 420 seconds total illumination time and approximately 270 milliwatts of laser power directed at the sample. The bottom spectral trace labeled a is the unpolarized parent Raman spectrum of the compound. The middle spectral trace labeled b shows circular difference spectrum recorded with the mostly linearly polarized laser light without application of any correction scheme. The observed signal for the dominant polarized band situated at approximately 1000 cm −1 is almost entirely due to the instrumental offset and is of the order of four percent of the parent Raman signal. The top spectral trace labeled c shows the actual SCP-ROA spectrum obtained by introducing into the light path of the exciting light the optical elements shown in FIG. 3 and a circularity converter into the path of the scattered light. (The linear polarization rotator was not used in the optical path of the scattered light because the absence of measurable offsets in the light collection optics and the scattering cell.) It is seen that the actual SCP-ROA signal which is the signal of interest of the 1000 cm −1 signal, is at most of the order of ±2×10 −5 of the size of the parent Raman signal and the instrument offset is reduced by more than a factor of 2000 by the use of the present invention.
FIG. 6 demonstrates the importance of the use of the circularity converter described in the invention. The bottom trace d was recorded with the linear rotator and the circular rotator in the exciting light path. No other correction elements were in the excitation light path. Instrumental offset for the 1000 cm −1 signal is larger than six parts in ten thousand, which is over thirty times the actual ROA signal. This is typical of the best result one might expect from the use of a stress induced birefringent fiber optics polarization scrambler in the exciting light. No improvement would result from the additional use of a linear rotator in the scattered light.
The middle trace labeled e in FIG. 6 shows the effect of the introduction of a circularity converter into the scattered light only. Incremental reduction in the instrumental offset is visible but minor.
The top trace labeled f in FIG. 6 demonstrates the effect of the introduction of the circularity converter into the exciting light only. So in the top trace all three elements of the invention as shown in FIG. 3 are in the exciting light path. The instrumental offset reduction for the 1000 cm −1 signal is about five times as effective as compared to the bottom trace of FIG. 6 . The comparison with the actual ROA spectrum (c of FIG. 5 ) shows that the circularity converters in both the exciting and the scattered light are required for the reliable SCP measurement of ROA effects other than those with large ratios of ROA intensity to the intensity of the parent Raman band.
Experimenters skilled in the optical arts can determine other benefits of the invention by placing a single element or multiple elements of the invention in to the light path and determining the resulting spectrum. Those skilled in the optical arts may see further applications of the invention, such as incident circular polarization Raman optical activity, dual circular polarization Raman optical activity, electronic and vibrational circular dichroism instruments. The time-average signal that is available and is free from offsets can be used in either scattering or circular dichroism applications to obtain highly precise spectra. This description of the invention is designed to describe embodiments that might be useful to those skilled in the optical arts. Placing the invention in the exciting light path, the transmitted light path, or the scattered light path will have various beneficial effects for experimenters skilled in the optical arts. In addition, it is possible to combine the present invention in the dual polarization modulation spectrometer as described in U.S. Pat. No. 6,480,277 (Nafie, 2002) | The invention describes a method to eliminate instrumental offset in measurement of optically active scattering and circular dichroism. The method uses the time-average measurement of the light that is systematically transformed by a series of optical devices. The optical devises perform the function of rotating linearly polarized light, interconverting left and right circular polarized light, converting circular polarized light to rotating linear polarized light and converting linear polarized light to alternating left and right circular polarized light. | 6 |
This application is a 371 of PCT/DE95/00416 filed Mar. 26, 1995 and also claims priority under 35 U.S.C. §119 of U.S. application ser. No. 60/004,117, filed Sep. 21, 1995.
FIELD OF THE INVENTION
This present invention covers a procedure for producing a transponder unit provided with at least one chip and a coil, and in particular a chip-mounting board where the chip and the coil are mounted on one common substrate and the coil is formed by the installation of a coil wire and the ends of the coil wire are connected with the contact surfaces of the chip on the substrate.
BACKGROUND OF THE INVENTION
The procedures employed in prior art for producing chip-mounting boards involve the placement of coils for instance on a film carrier into which the individual windings are etched, as described in EP-A2-0 481 776, or of separate, prewound coils which are then mounted on a board substrate either together with the chip as one assembly or as individual components to be connected with the chip on the substrate.
The aforementioned etching process used to apply coil windings on a substrate is very complex and the process lends itself only to coils having a relatively low copper density, which means that transponder units so equipped offer correspondingly low transmitting power. Using prewound coils in the production of a transponder in turn involves complicated coil handling in the insertion and attachment of the coils followed by fusing or gluing the coil to the substrate. Hence, apart from the coiling process proper, additional processing and handling steps are required in producing a transponder unit employing a prewound coil. The overall procedure is thus again quite complex, time-consuming and expensive.
OBJECTS AND SUMMARY OF THE INVENTION
The objective of the invention here presented is to provide a procedure for producing a chip-mounting board, and the chip-mounting board itself, which permits simple and cost-effective production of such chip-mounting boards.
This objective is realized by means of a procedure for producing a chip-mounting board characterized by the procedural features according to claim 1, and a chip-mounting board having the design features according to claim 4.
In the procedure according to this invention, the chip and the coil are mounted on one common substrate and the transponder unit is created in that a coil wire is laid out on the substrate in a way as to form a coil and the ends of the coil wire are connected to the contact surfaces of the substrate-mounted chip.
Applying the coil-wire windings directly on the substrate obviates the need for the use of a prewound coil and the handling and mounting of the latter on the chip. Instead, the coil is created on the substrate itself, which offers the added benefit of permitting the formation of the coil and the connection of the coil-wire ends to the contact surfaces of the chip in one continuous or nearly simultaneous operation.
In a particularly desirable approach, the procedure begins with the connection of one coil-wire end to a first contact surface of the chip, followed by the application of the coil windings on the substrate and, finally, the connection of the open coil-wire end to a second contact surface of the chip. As the coil wire is laid out to form the coil, the coil wire is attached to the substrate at least in some locations so as to give the coil a fixed, rigid structure.
This "embedded" coil thus eliminates not only the separate winding process used in producing a conventional prewound coil but also the mutual "baking-together" of the individual windings required in conventional prewound coils.
In a manner similar to that in attaching the coil wire of the embedded coil to the substrate, the chip can be bonded to the substrate at the time the chip is mounted. This eliminates the need for special positioning provisions on the substrate. Instead, the entire transponder unit can be applied to an unpreprocessed, flat surface of the substrate.
The embedding or bonding of the coil wire or the chip can be accomplished by thermal compression, i.e. thermally softening the surface of the substrate to allow the coil wire or chip to be pressed in, or by any other suitable process such as "rubbing" it into the surface using ultrasound.
A particularly useful approach in installing the coil wire so as to be bonded to the substrate at least in some locations and for connecting the coil-wire ends to the contact surfaces of the chip involves the use of a bonding head, described in detail as a winding/bonding device in the same claimant's German patent application P 43 25 334.2. This bonding head incorporates the functionalities of a wire guide, a wire-connecting device and a wire cutter and is movable relative to the substrate. The chip can be mounted using a pick-and-place device that may be employed in conjunction with the above-mentioned bonding device.
The chip-mounting board according to this invention offers the features described in claim 4 and is provided with a substrate-mounted transponder unit which includes at least one chip and one coil, the coil-wire ends of which are connected with contact surfaces of the chip, wherein one or several coil-wire windings constituting the coil is/are placed in one plane on the substrate and bonded to the substrate at least in some locations.
The chip-mounting board according to this invention, by virtue of its design, permits production by a method which offers the advantages already mentioned above in conjunction with the procedure according to this invention, meaning production that is considerably simpler than that of conventional chip-mounting boards.
The term "chip-mounting board" is intended to cover all transponder applications employing a board- or card-like substrate. This also includes for instance fixed modules or plug-in boards which, unlike data boards or ID cards, are not subject to constant handling.
Placing the individual coil-wire windings in one plane offers the special advantage of giving the coil substantially higher transverse, flexural strength than that of complex, three-dimensional prewound coils. This in turn greatly improves the functional reliability of the chip-mounting board even when exposed to frequent bending stress.
Moreover, the coil produced by the embedded-application process may be positioned anywhere on the substrate without its contour having to abide by the constraints of a predetermined winding matrix. A particularly advantageous approach in this context involves an at least partially meandering or zigzag configuration of the coil-wire windings in their application on the substrate. The coil can thus be made particularly sturdy in terms of flexural strength in that part of the substrate which is most affected by bending stress, thus further increasing the aforementioned operational reliability of a chip-mounting board provided with this type of coil.
The substrate of the chip-mounting board according to this invention may also support other components in addition to the coil and the chip. This is possible by virtue of the above-mentioned fact that the "embedded" coil does not have to follow a particular predetermined pattern but may be configured in any desired fashion. This allows the placement of complex assemblies on the substrate, with the spaces between the individual components being available for installing the coil wire.
One desirable variation of the substrate-mounted assembly design involves the integration of a membrane-type touch-sensitive key or keyboard. This makes it possible to manually activate the transponder unit or to enter data such as a key code.
Depending on the intended use of the chip-mounting board, the substrate and the components mounted thereon may at least in part be covered with a layer which may serve either as a purely protective coating or as a functional layer carrying, for instance, advertising or visual identification information.
The following describes a preferred implementation of the procedure according to this invention as well as a preferred design version of the chip-mounting board according to this invention, with the aid of the diagrams.
DESCRIPTION OF THE FIGURES
FIG. 1 shows a device for installing a coil wire on a substrate, as a design example serving to explain the procedure according to this invention;
FIG. 2 shows, by way of example, a design version of a chip-mounting board produced using the procedure illustrated in FIG. 1;
FIG. 3 shows another design version of the chip-mounting board;
FIG. 4 shows yet another design version of the chip-mounting board;
FIG. 5 shows a design version of the chip-mounting board according to this invention, incorporating a multi-component assembly;
FIG. 6 shows another design variation of the chip-mounting board.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 depicts the design of an embedding/bonding device 10 as described in the German patent application P 43 25 334.2 and included in this present patent application by way of reference to its technical substance, incorporating tools attached to and guided by a tool holder 11, such as a wire guide 12, a wire-connecting device 13 and a wire cutter 14. The aforementioned patent application describes these tools in detail so that the following description need not go into specifics.
Located underneath the embedding/bonding device 10 is a board-shaped substrate 15 carrying a chip 16 so as to form a chip card 17.
The chip 16 is mounted on the substrate 15 for instance by means of a pick-and-place device, not illustrated in detail. The chip 16 can be attached to the substrate 15 for instance by way of an adhesive layer preapplied on the top surface of the substrate 15 or bottom surface of the chip 16. The chip may also be applied in the form of a chip module together with its own chip substrate.
Producing a coil 18 on the chip card 17 begins by connecting a free coil-wire end 19, emanating from the wire guide 12, to a first contact surface 20 of the chip 16. To that effect, the coil-wire end 19 of a coil wire 21 paid out by the wire guide 12 is clamped between the wire-connecting device 13, in this case of the thermal compression type, and a first contact surface 20 of the chip 16 and connected to the latter. For connecting to the contact surface a relatively thick coil wire such as the wire used in RF coils, having a diameter of about 100 μm, soldering has been found to be a preferred method, where the contact surfaces of the chip are in the form of tin-coated gold bumps. If, due to its composition, the coil wire used is bondable without (baked-enamel) insulation, the coil wire may be directly connected to the aluminum pads of the chip. In this case it will be particularly useful to make the connection using the ultrasound or the thermal compression process.
When insulated wire is used, it may be desirable to strip the wire by means of the wire stripper that is integrated in the embedding/bonding device. The wire stripper may be combined with a length-measuring system for marking the correct point where the insulation is to be stripped as a function of the length of the embedded coil. When a laser bonding unit is incorporated in the said embedding/bonding device, it can also double as a wire stripper.
Following the connection of the coil-wire end 19 to the first contact surface 20, the coil wire 21 is now laid out by means of the embedding/bonding device 10. To that effect, as shown in FIG. 1, the coil wire 21 is guided by the wire guide 12 across the substrate surface, partly in a straight line and partly along a meandering path, and at every point where the coil wire 21 changes direction it is bonded to the surface of the substrate 15 at the connecting points 22. To accomplish this, the wire guide 12 and the embedding/bonding device 10 are jointly moved in a biaxial (X-Y) direction across the plane of the substrate 15 and at every connecting point 22 the bonding device 13 makes a dipping movement (along the Z-axis), whereby the coil wire is temporarily clamped between the bonding unit 13 and the surface of the substrate and then pressed and thermally fused into the latter.
Following the formation of a coil 18 of the design shown in FIG. 1, a coil-wire end 23 paid out by the wire guide 12 is clamped by the bonding device 13 against a second contact surface 24 of the chip 16 and thermally as well as pressure-bonded to that surface. Thereupon the wire cutter 14 is activated to cut the end 23 of the continuous coil wire, the result of the process being a transponder unit 55 surface-mounted on the substrate 15 and consisting of the chip 16 and the coil 18 connected therewith.
In the form illustrated in FIG. 1, the embedding/bonding device 10 described above serves as an example only. Correspondingly, the bonding unit 13 of the embedding/bonding device 10 may be designed for instance as an ultrasonic (thermosonic) bonding unit, or it may be equipped with a laser bonding head and a fiber-optic cable which head, either by direct contact or via a light-conducting contact element, produces the connecting points 22 or serves to bond the coil wire 21 to the contact surfaces of the chip.
FIGS. 2 to 4 show examples of other possible layout patterns for mounting the coil wire 21 on the surface of a substrate 15 in a way as to form coils 25, 26 or 27 and for establishing the connection between the coil wire 21 and the contact surfaces 20, 24 of the chip 16, in each case creating differently configured transponder units 28, 29, 30 on the substrates 15. For the purpose of producing the meandering layout pattern shown here by way of example, several connecting points 31, 32 and 33, respectively, are provided between the coil wire 21 and the surface of the substrate 15 so as to form the serpentine pattern 34 of the coil wire.
It will be evident from the illustration in FIG. 5 that the placement of the coil wire 21 on the surface of the substrate 15 can be used not only for creating a coil 35 but also for running interconnecting wires 41, 42, 47, 48 between contact surfaces 20, 24, 43 to 46 and 49 to 52 of individual components 36, 37 and 38. The example of an assembly shown in FIG. 5 includes a chip 36, a battery element 37 and a touch-sensitive membrane-type key 38. In this case the coil wire 21 of the coil 35 is connected to the contact surfaces 20, 24. The interconnecting wires 41, 42 extend between the contact surfaces 43 and 44, respectively, of the battery element 37 and the contact surfaces 45 and 46, respectively, of the chip 36. The interconnecting wires 47, 48 link the contact surfaces 49 and 50 of the touch-sensitive key 38 respectively to the contact surfaces 51 and 52 of the chip 36.
The interconnecting wires 41, 42 and 47, 48 may be of the same coil wire 21 as the coil 35 and, in the same way as the coil wire forming the coil 35, they may be installed on the surface of the substrate 15 and bonded to the contact surfaces of the components by means of the embedding/bonding device 10.
As indicated by the shaded area in FIG. 5, the surface of the substrate 15 along with the components 36, 37 and 38 as well as the coil 35 and the interconnecting wires 41, 42, 47, 48 mounted thereon may be provided with a covering layer 53, leaving exposed only a contact window 54 for the touch-sensitive key 38. The covering layer 53 may for instance be in the form of a laminate or may be adhesively applied on the surface of the substrate 15 in any other suitable fashion.
FIG. 6 shows a chip card on which the coil wire 21 used to produce a coil 56 is first connected to the contact surface 20 whereupon, in laying out the coil, each winding is carried across the surface of the chip 16 and the coil is ultimately connected to the second contact surface 24. In this fashion, it is not necessary as in the design per FIG. 4 to run the coil wire across the windings of the coil in order to establish the connection with the second contact surface. This allows for the production of particularly thin chip cards i.e. chip-mounting boards. | Procedure for producing a transponder unit (55) provided with at least one chip (16) and one coil (18), and in particular a chip card/chip-mounting board (17) wherein the chip and the coil are mounted on one common substrate (15) and the coil is formed by installing a coil wire (21) and connecting the coil-wire ends (19, 23) to the contact surfaces (20, 24) of the chip on the substrate. | 7 |
BACKGROUNS OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to a recording medium such as a compact disc and, more particularly, to a recording medium for storing information to be protected from an unauthorized access.
[0003] 2. Description of the Related Art
[0004] In recent years, portable optical discs having a large capacity have become popular as a recording medium used with a personal computer. A read only type compact disc (CD-ROM) has become very popular. A recordable compact disc (CD-R) or a rewritable compact disc (CD-RW) is a typical recordable recording medium used with a personal computer.
[0005] In many cases, information recorded on a recording medium such as a CD-R or a CD-RW is created by the owner of the recording medium so as to be used by the owner or limited persons authorized by the owner. Additionally, in some cases, information recorded on the recording medium contains very important contents such as secret business information. Thus, a damage due to lost of such a recording medium or an unauthorized access to such a recording medium is inestimable.
[0006] Additionally, it has become important to protect information recorded on a CD-ROM from an illegal copy in light of copyright.
[0007] Accordingly, various techniques have been suggested to prevent illegal use of such a recording medium. In order to prevent an illegal access to information (programs or data) recorded on a recording medium or an illegal copy of such information, Japanese Laid-Open Patent Applications No.5-257816 and No.6-295521 disclose protecting methods using a licensing key (individual number key) or an enciphering technique.
[0008] Additionally, Japanese Laid-Open Patent Applications No.11-134650, No.11-134719 and No.11-134813 suggest measures taken for a recording method of a recording medium or a recording and reproducing apparatus.
[0009] However, practically in a data processing apparatus such as a personal computer using an operating system, there are many cases in which a recording medium is mounted on an apparatus. In this case, the term “be mounted on” means that a recording or reproducing operation with respect a recording medium can be performed through a drive apparatus due to predetermined information (for example, root directory information defined as a normal file system) recorded at a predetermined position of the recording medium. That is, an access can be made to information recorded on a recording medium by controlling the drive apparatus for reading or writing the recording medium. Thus, the above mentioned methods using the licensing key or enciphering technique are not so effective. Additionally, enciphered information may be illegally used by analyzing the enciphering algorithm.
[0010] On the other hand, if the measures suggested in Japanese Laid-Open Patent Applications No.11-134650, No.11-134719 and No.11-134813 are to be taken, such measures cannot be applied to recording and reproducing apparatuses that are already on the market. Thus, such measures must be applied to a new apparatus, and there needs a time to introduce such a new apparatus into the market.
SUMMARY OF THE INVENTION
[0011] It is a general object of the present invention to provide an improved and useful recording medium in which the above-mentioned problems are eliminated.
[0012] A more specific object of the present invention is to provide a recording medium having information which can be accessed exclusively by a particular person in a general circumstance of using a recording medium such as a personal computer circumstance.
[0013] Another object of the present invention is to provide a method for accessing a recording medium on which data is recorded according to a directory structure, the data recorded on the recording medium being protected from being accessed by an unauthorized person.
[0014] In order to achieve the above-mentioned objects, there is provided according to one aspect of the present invention a recording medium storing data having a directory structure, comprising: a first section in which a first set of root directory information is recorded; and a second section in which a second set of root directory information is recorded, the second section being located at a predetermined position different from a position of the first section, wherein the first set of root directory information is a part of the second set of root directory information.
[0015] According to the present invention, the contents of data recorded on the recording medium is presented to a user by accessing the first root directory information which is a part of the second root directory information. When the contents of the first root directory information is shown in accordance with the first root directory information, only a part of the contents of the data recorded on the recording medium is shown. Thus, the user cannot access the contents of which information is not included in the first root directory information.
[0016] In the recording medium according to the present invention, the first set of root directory information may indicate that only a root directory is present, and the second set of root directory information indicates all directories and files of the data recorded on the recording medium.
[0017] Accordingly, if the first set of root directory information is accessed by an unauthorized person and the second set of root directory can be accessed only by an authorized person, the data recorded on the recording medium can be accessed only by the authorized person. If the unauthorized person attempts to access the data recorded on the recording medium, only a root directory is presented to the unauthorized person. Accordingly, the data recorded on the recording medium is prevented from being accessed by an unauthorized person.
[0018] Additionally, in the recording medium according to the present invention, recording medium discrimination information may be recorded at a predetermined position on the recording medium, the recording medium discrimination information indicating whether or not the second set of root directory information is recorded. Thus, if the recording medium discrimination information is recorded on the recording medium, an attempt can be made to read the second root directory information to access the whole data recorded on the recording medium.
[0019] Additionally, in the recording medium according to the present invention, root directory position information is recorded at a predetermined position on the recording medium, the root directory position information indicating a position of the second section. Accordingly, the second root directory information can be accessed by reading the root directory position information.
[0020] Additionally, in the recording medium according to the present invention, root directory access information may be recorded at a predetermined position specified in an existing standard, the root directory access information indicting the position of the first section. Accordingly, the recording medium according to the present invention can be read by a conventional drive apparatus, which is operated according to the existing standard. However, since only the first root directory information can be accessed by the conventional drive apparatus, the data recorded on the recording medium cannot be accessed by the conventional drive apparatus.
[0021] Additionally, there is provided according to another aspect of the present invention a method for accessing a recording medium, comprising the steps of: discriminating whether the recording medium has both a first set of root directory information and a second set of root directory information, the first set of root directory information indicating only a root directory of data recorded on the recording medium, the second set of root directory information indicating all directories and files of the data recorded on the recording medium; determining whether a person, who is accessing the recording medium, is an authorized person when the recording medium has the second sets of root directory information; and reading root directory position information recorded at a predetermined position on the recording medium only when the person is determined to be the authorized person, the root directory position information indicating a position at which the second set of root directory information is recorded.
[0022] The method according to the present invention may further comprise a step of reading root directory access information recorded at a predetermined position on the recording medium when the person is determined to be an unauthorized person, the root directory access information indicating a position at which root directory information containing information with respect to only a root directory of the data recorded on the recording medium is recorded.
[0023] Additionally, the step of discriminating may include a step of reading recording medium discrimination information recorded at a predetermined position on the recording medium, the recording medium discrimination information indicating whether or not the second set of root directory information is recorded.
[0024] The method according to the present invention may further comprise a step of reading root directory access information recorded at a predetermined position on the recording medium when the recording medium does not have the second set of directory information, the root directory access information indicting a position at which the first set of root directory information is recorded.
[0025] Additionally, the step of determining may include the steps of: requesting the person to input certification information; and determining whether or not the certification information is correct so that the person is determined to be the authorized person when the certification is correct.
[0026] Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] [0027]FIG. 1 is a block diagram of an optical disc apparatus that performs an accessing method according to an embodiment of the present invention.
[0028] [0028]FIG. 2A is an illustration of an arrangement of root directory information recorded on an optical disc according to the embodiment of the present invention;
[0029] [0029]FIG. 2B is an illustration of an arrangement of root directory information recorded on an optical disc according to a recording method specified by an existing standard;
[0030] [0030]FIG. 3 is an illustration of a directory structure of data recorded on an optical disc;
[0031] [0031]FIG. 4 is a flowchart of a method for accessing an optical disc according to the embodiment of the present invention; and
[0032] [0032]FIG. 5 is a flowchart of a method for accessing an optical disc according to an existing standard.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] A description will now be given, with reference to the drawings, of an embodiment of the present invention.
[0034] [0034]FIG. 1 is a block diagram of an optical disc apparatus that performs an accessing method according to an embodiment of the present invention. The optical disc apparatus shown in FIG. 1 writes information on and read information from a recording medium such as an optical disc 1 . The optical disc apparatus comprises a drive apparatus 2 on which the optical disc 1 is mounted and an information processing apparatus 3 that exchanges information with the drive apparatus 2 and performs other processes.
[0035] The optical disc 1 can be a read only compact disc CD-ROM, a recordable compact disc CD-R or a rewritable compact disc CD-RW. Thus, the drive apparatus 2 may be a CD-ROM drive having a reading function or a CD-R/RW drive having a writing function. The drive apparatus 2 and the information processing apparatus 3 may be incorporated into a single unit.
[0036] The drive apparatus 2 comprises a reading part 4 as reading means and a connecting part 5 as connecting means. The reading part 4 optically reads information recorded on the optical disc 1 by an optical pickup. The connecting part 5 connects the information processing apparatus 3 to the drive apparatus 2 . When the drive apparatus 2 is a CD-R/RW apparatus having a writing function, a writing part 6 having an optical pickup as writing means is provided in the drive apparatus 2 so as to write information on the optical disc 1 in accordance with a write instruction provided from the information processing apparatus 3 .
[0037] The information processing apparatus 3 comprises connecting part 7 as connecting means, a reproducing part 8 as reproducing means, an output part 9 as output means, an input part 10 as input means, and a certificate analyzing part 11 as certificate analyzing means. The connecting part 7 connects the information processing apparatus 3 with the connecting part 5 of the drive apparatus 2 . The reproducing part 8 processes various information read from the optical disc 1 . The output part 9 outputs the information reproduced by the reproducing part 8 . A user accessing the optical disc 1 supplies information such as certificate information through the input part 10 . Certificate analyzing part 11 analyzes whether or not the certificate information input through the inputting part 10 is correct. In the present embodiment, software 12 for using a recording medium is installed in the information processing apparatus 3 so as to control an access to the optical disc 1 mounted on the drive apparatus 2 by controlling operations of the reproducing part 8 and the certificate analyzing part 11 .
[0038] A description will now be give, with reference to FIGS. 2A and 2B, of an information storing structure of the optical disc 1 . FIG. 2A illustrates an arrangement of root directory information recorded on the optical disc 1 according to the embodiment of the present invention. FIG. 2B illustrates an arrangement of root directory information recorded on the optical disc 1 according to a recording method specified by an existing standard.
[0039] The arrangement of information recorded on the optical disc 1 shown in FIG. 2B is in accordance with a recording method specified by an existing standard such as an ISO9660 file system or a Universal Disc Format (UDF) file system. The root directory access information is stored in a section or area 1 a starting from a predetermined position. For example, the directory access information is stored in the Primary Volume Descriptor according to the ISO file system, or stored in the File Set Descriptor (FDS) according to the UDF file system. Additionally, the root directory information is stored in a section or area 1 b different from the section or area 1 a storing the root directory access information. Pointer information indicating the start address of the sector or area 1 b storing the root directory information is included in the root directory access information. Accordingly, the root directory access information is read first, and then the root directory information can be read by referring to the pointer information indicating the start address of the section or area 1 b storing the root directory information. The data recorded on the optical disc 1 , which includes directories or files, is read by referring to the root directory information.
[0040] On the other hand, information recorded on the optical disc 1 shown in FIG. 2A, which is in accordance with the embodiment of the present information, includes additional information such as root directory position information. Additionally, the information recorded on the optical disc 1 shown in FIG. 2A includes two sets of root directory information such as first root directory information and second root directory information. Further, the information recorded on the optical disc 1 shown in FIG. 2A includes recording medium discrimination information, which indicates a type of a recording medium.
[0041] The root directory position information is stored in a sector or area If starting from a predetermined position (address). Similar to that shown in FIG. 2B, the root directory access information stored in the sector or area 1 a includes pointer information indicating a start position (start address) of a section or area 1 c in which the first root directory information is stored. Additionally, the root directory position information stored in the sector or area if includes pointer information indicating a start position (start address) of a section or area id in which the second root directory information is stored. Accordingly, the second root directory information can be read by referring to the pointer information included in the root directory position information stored in the section or area if of which position is fixed.
[0042] The recoding medium discrimination information is stored in a section or area 1 e starting from a predetermined position (address). The recording medium discrimination information indicates whether or not the optical disc 1 is of a type which has the root directory position information stored in the section or area If. That is, if the recording medium discrimination information is recorded on the optical disc 1 , the root directory position information is read by accessing the section or area if. Otherwise, the root directory access information store in the section or area 1 a is read so that the first root directory information is read.
[0043] A description will now be given, with reference to FIG. 3, of the difference between the first root directory information and the second root directory information. FIG. 3 is an illustration showing a directory structure of data recorded on the optical disc As shown in FIG. 3, the first root directory information is a part of the second root directory information. That is, the first root directory information includes only information regarding a root directory. The second root directory information includes information regarding all directories and files recorded on the optical disc 1 .
[0044] In the directory structure shown in FIG. 3, the root directory has directories D 1 and D 2 and files FR- 1 and FR- 2 . Additionally, the directory D 2 has a subdirectory SD 2 and files FD 2 - 1 and FD 2 - 2 . The subdirectory SD 2 has a file SD 2 - 1 .
[0045] The second root directory information includes information regarding all of the directories D 1 , D 2 and SD 2 and files FR- 1 , FR- 2 , FD 2 - 1 , FD 2 - 2 and FSD 2 - 1 that are arranged under the root directory. Thus, any one of the directories or files under the root directory can be accessed by referring to the second root directory information. That is, the whole data recorded on the optical disc 1 can be accessed by referring to the second root directory information, which can be read in accordance with the pointer information included in the root directory position information.
[0046] On the other hand, since the first root directory information includes only information regarding the root directory, one cannot merely recognize the root directory by through the first root directory information. That is, the directories and files under the root directory cannot be indicated when the first root directory information is read. Accordingly, when the first root directory information is read, one can recognize as if the optical disc 1 has only the root directory and there is no data recorded on the optical disc 1 .
[0047] A description will now be given, with reference to FIG. 4, of a method for accessing an optical disc according to the embodiment of the present invention. FIG. 4 is a flowchart of the method for accessing a recording medium according to the present invention.
[0048] The routine shown in FIG. 4 starts when the optical disc 1 is loaded to the drive apparatus 2 . When the optical disc 1 is loaded to the drive apparatus 2 , the drive apparatus sends information to the information processing apparatus 3 via the connecting parts 5 and 7 , and thereby the software 12 for using a recording medium is started.
[0049] Then, it is determined, in step S 1 , whether or not the recording medium discrimination information is recorded on the optical disc 1 by reading the section 1 e of the optical disc 1 . If it is determined that the recording medium discrimination information is not recorded, it is determined that the optical disc 1 is a regular optical disc, and the routine proceeds to step S 5 . In step S 5 , the section 1 a is read so as to obtain the root directory access information stored in the section 1 a , and, thereafter, access the root directory information stored in the section 1 b as shown in FIG. 2B.
[0050] On the other hand, if the recording medium discrimination information is recorded, the routine proceeds to step S 2 . In step S 2 , a request is made to a user to input attestation information such as a password so as to determined whether or not the user is an authorized person. Accordingly, it is determined, in step S 3 , whether or not the attestation information is input. If no input is give by the user, the process of step S 3 is repeated. If the attestation information is input through the input part 10 in response to the request, the routine proceeds to step S 4 .
[0051] Then it is determined, in step S 4 , whether or not the user is an authorized person by analyzing the attestation information by the analyzing part 11 and comparing the analyzed attestation information with attestation information previously registered in the software 12 .
[0052] If it is determined that the user is an authorized person, the routine proceeds to step S 6 . In step S 6 , the root directory position information stored in the section if is read first, and, then, the second root directory information stored in the section 1 d is read by referring to the pointer information included in the root directory position information. Thereby, the data recorded on the optical disc 1 can be recognized on a display. That is, the entire directory structure of the data recorded on the optical disc 1 is displayed on the display as shown in FIG. 3. Thus, the user can select any desired file or directory to be accessed. This means that the user is permitted to access the data or information recorded on the optical disc 1 .
[0053] On the other hand, if it is determined, in step S 4 , that the user is not an authorized person, the routine proceeds to step S 7 . In step S 7 , the root directory access information stored in the section 1 a is read, and, thereafter, the first root directory information stored in the section 1 c is read. At this time, since the first root directory information indicates as if only the root directory is present, the directories or files under the root directory cannot be accessed buy the user. That is, the user cannot recognize the directories and files under the root directory, thereby preventing an access to the data recorded on the optical disc 1 . For example, if the Windows® of Microsoft is installed as the operating software, only the root directory is indicated on the Explore® window. Thus, an authorized person is prohibited from accessing the data recorded on the optical disc 1 .
[0054] According to the above-mentioned embodiment of the present invention, the data recorded on the optical disc 1 loaded to the drive apparatus 2 is hidden, when an unauthorized person attempts to read the data recorded on the optical disc 1 , due to the software 12 effecting the first root directory information, which includes information regarding only the root directory. On the other hand, when the user inputs the correct attestation information and is determined as an authorized person, the user can access the data recorded on the optical disc 1 due to the software 12 effecting the second root directory information, which includes information regarding all directories and files of the data recorded on the optical disc 1 .
[0055] A description will now be give, with reference to FIG. 5, of a case in which the optical disc 1 according to the present embodiment is loaded to a disc drive apparatus which does not have software such as the software 12 . FIG. 5 is a flowchart of an operation performed a disc drive apparatus, which does not have a function to discriminate the optical disc according to the present embodiment.
[0056] When the optical disc 1 according to the present embodiment is loaded in a regular disc drive apparatus, the root directory access information is read first since the software of the regular disc drive apparatus does not have a function to discriminate the type of the optical disc and a function to determine whether the user is an authorized person. Accordingly, in step S 11 , the root directory access information stored in the section or area 1 a is read in accordance with a regular procedure of reading an optical disc, and, thereby, the first root directory information stored in the section 1 f is read. Thus, the information regarding only the root directory is displayed, which results in the user being prevented from accessing the directories and files under the root directory. Accordingly, the data recorded on the optical disc 1 cannot be accessed by an unauthorized person using a regular disc drive apparatus.
[0057] The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the present invention.
[0058] The present invention is based on Japanese priority application No.2000-050394 filed on Feb. 28, 2000, the entire contents of which are hereby incorporated by reference. | A recording medium can store data which can be accessed exclusively by a particular person in a general circumstance of using a recording medium such as a personal computer circumstance. The recording medium stores the data having a directory structure. A first set of root directory information is recorded in a first section. A second set of root directory information is recorded in a second section located at a predetermined position different from the position of the first section. The first set of root directory information is a part of the second set of root directory information. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the US National Stage of International Application No. PCT/EP2004/008052, filed Jul. 19, 2004 and claims the benefit thereof. The International Application claims the benefits of European Patent application No. 03019002.9 EP filed Aug. 21, 2003. All of the applications are incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
The invention relates to a stationary gas turbine having a segmented inner ring for holding guide vanes. It also relates to a method for assembling a segmented inner ring for guide vanes of a stationary gas turbine.
BACKGROUND OF THE INVENTION
DE 37 12 628 has disclosed an inner ring for holding guide vanes of a stationary gas turbine. The guide vanes which are arranged in a star shape around the rotor to form a guide vane ring are secured to the housing of the gas turbine by means of their radially outer guide vane roots. The radially extending guide vanes, on their side facing the rotor, have the guide vane head, which is connected to the stationary inner ring. This inner ring, which is U-shaped in cross section, engages coaxially around the rotor of the gas turbine and connects the guide vanes of a guide vane ring to one another in order to increase the stability of the guide vane ring and to improve the vibrational properties of the guide vanes. A gap is in this case formed between the web of the U-shaped inner ring, its flanks and the corresponding circumferential and end faces associated with the rotor. Likewise, the web of the U-shaped inner ring, on its surface facing the rotor, has one half of a labyrinth seal, which together with the second half arranged on the rotor forms the labyrinth seal.
When the gas turbine is operating, the working fluid which flows within the flow passage is only supposed to flow past the guide vanes of a guide vane ring. However, the working fluid can also flow through the gap formed by stationary and rotating components, as a leakage flow.
To reduce the extent of the leakage flow, the gap between the stationary and rotating components is sealed by means of the labyrinth seal.
Furthermore, it is known to provide a plurality of labyrinth seals in the gap between the flank of the inner ring and of the shaft shoulder, in order to achieve an improved sealing action. In this case, two labyrinth seals are arranged axially and radially offset with respect to one another, in a terraced arrangement, in the gap between the flank and shaft shoulder.
The terraced arrangement of a plurality of labyrinth seals takes up a large amount of space and is only used for stationary gas turbines. Stationary gas turbines have a parting plane located between a lower housing half and an upper housing half and are fitted together radially during assembly. In the process, the finished rotor is inserted into the lower housing half, which has already been preassembled and onto which the upper housing half is then fitted, so that only labyrinth seals which are offset in terraced fashion with respect to one another are possible between the rotor and the housing.
U.S. Pat. No. 5,222,742 has disclosed a stacked labyrinth seal between the securing ring for the guide vane of a turbine and a rotor blade mounted on the rotor of the turbine. The turbine is an axially assembled aircraft turbine, i.e. the axially successive rotor blade rings and guide vane rings of the individual compressor stages and/or turbine stages are mounted in succession ring by ring, so that a stacked arrangement is possible. Further labyrinth seals which have been stacked in this way for aircraft turbines are known from DE 199 31 765 and FR 2 241 691.
Since stacked labyrinth seals have hitherto only been known for aircraft turbines, a person skilled in the art was not hitherto in a position to transfer stacked labyrinth seals to stationary gas turbines, on account of the axial method of assembly.
SUMMARY OF THE INVENTION
Therefore, the object of the invention is to design a stationary gas turbine with a parting gap in such a way that the leakage flow is reduced by means of the stacked arrangement of labyrinth seals which is known from aircraft turbines. A further object is to provide a method for assembling an inner ring which allows a stacked arrangement of labyrinth seals.
The object relating to the gas turbine is achieved by the features herein disclosed. The object relating to the method is also achieved by the features herein disclosed. Advantageous configurations are given in this specification.
By carrying out the working steps of the invention, it is now possible for the first time for the arrangement of stacked labyrinth seals which is known from aircraft turbines also to be transferred to stationary gas turbines. It is therefore possible for a plurality of labyrinth seals which are stacked radially on top of one another to be arranged in a stationary gas turbine with a parting plane, and for the improved sealing action which ensues to be utilized for a stationary gas turbine. The leakage flow which reduces the efficiency of the stationary gas turbine is considerably reduced as a result.
The space required for the radially stacked labyrinth seals is reduced compared to the terraced arrangement. In particular, the size of the seal and of the entire inner ring in the axial direction have been reduced.
A gas turbine of this type is dismantled by carrying out the working steps of the invention in the reverse order.
If each labyrinth seal has a first coaxial balcony on the end side of the inner ring and a further coaxial balcony on the shaft shoulder, which balconies each, project in the axial direction, it is possible for the two balconies, in the assembled state of the inner ring, to lie radially opposite one another. This stacked arrangement of the balconies allows the series connection of labyrinth seals and forms a meandering gap for the leakage flow.
The labyrinth seal is advantageously formed by a sealing surface and at least one sealing tooth, the first balcony having the coaxial sealing surface, which faces the further balcony, and the further balcony, on its circumferential surface which faces the first balcony, having at least one circumferential sealing tooth which extends toward the sealing surface.
For axial securing purposes, the inner ring can be fixed to the rotationally fixed modules and/or to the guide vanes.
If the inner ring is arranged between two rotor blade rings, it can be secured against axial displacement by means of a securing ring. In this case, the securing ring is segmented and is mounted on the guide vane.
It is expedient for the securing ring to be arranged upstream of the inner ring.
It is advantageous for the sealing surfaces and the sealing teeth provided on the balconies to be designed in such a manner that intended axial displacement of the rotor counter to the direction of flow of the working fluid is possible without any change in the sealing action. Consequently, while the gas turbine is operating the rotor can be displaced without any deterioration in the sealing action. This is important in particular if the gap between the rotor blade tip and the radially outer, conical inner wall of the hot gas duct is to be reduced in size by the displacement of the rotor.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained with reference to a drawing, in which:
FIG. 1 shows a segmented securing ring for guide vanes of a first turbine stage,
FIG. 2 shows the segmented inner ring for the guide vanes of a second, third and fourth turbine stage, and
FIG. 3 shows a partial longitudinal section through a gas turbine.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 shows a stationary gas turbine 1 in the form of a partial longitudinal, section. In its interior, it has a rotor 3 , which is mounted such that it can rotate about an axis of rotation 2 and is also referred to as the turbine rotor or rotor shaft. An intake housing 4 , a compressor 5 , a toroidal annular combustion chamber 6 with a plurality of coaxially arranged burners 7 , a turbine 8 and the exhaust-gas housing 9 follow one another along the rotor 3 . The annular combustion chamber 6 in this case forms a combustion space 10 which is in communication with an annular hot-gas duct 11 , where four turbine stages 12 connected in series form the turbine 8 . Each turbine stage 12 is formed from two blade/vane rings. As seen in the direction of flow of a working fluid 14 , a guide vane ring 17 is followed in the hot-gas duct 11 by a ring 15 formed from rotor blades 18 . The guide vanes 16 are secured to the stator 19 , whereas the rotor blades 18 of a ring 15 are secured to the rotor 3 by means of a turbine disk 20 . A generator (not shown) is coupled to the rotor 3 .
The stationary gas turbine 1 has a housing 60 which with respect to a parting plane 61 running parallel to the horizontal plane can be divided into an upper housing half 62 and a lower housing half 64 . In the subsequent text using the terms “upward” and “downward” or “upper half of the . . . ” and “lower half of the . . . ”, this is in each case to be understood as meaning with respect to the parting plane 61 of the gas turbine 1 for the object in question.
While the gas turbine 1 is operating, the compressor 5 sucks in air 21 through the intake housing 4 and compresses it. The air 21 provided at the turbine end of the compressor 5 is fed to the burners 7 , where it is mixed with a fuel. The mixture is then burnt so as to form the working fluid 14 in the combustion space 10 . From there, the working fluid 10 flows past the guide vanes 16 and the rotor blades 18 in the hot-gas duct 11 . The working fluid 14 expands at the rotor blades 18 , transmitting its momentum as it does so, so that the rotor 3 is driven, and with it the generator coupled to it is also driven.
On their side facing the housing 13 , the guide vanes 16 have a guide vane root, by means of which they are hooked in an annular guide vane carrier. At their end facing the rotor 3 , i.e. the guide vane head, they are connected to an inner ring 30 .
FIG. 1 shows an excerpt from the gas turbine 1 between the guide vane 16 of the first turbine stage 12 and the rotor 3 . The inner wall, located on the radially inner side, of the combustion chamber 6 delimits the hot-gas duct 11 toward the inside. As seen in the direction of flow of the working fluid 14 , the guide vane 16 of the first turbine stage 12 is followed by the rotor blade 18 .
On the rotor 3 is the turbine disk 20 , which at its outer circumference holds the rotor blades 18 . To secure the rotor blades 18 against axial displacement, at a side wall 22 of the turbine disk 20 a covering element 23 is hooked to the turbine disk 20 by means of a plurality of radially spaced hooks. The covering element 23 , together with the turbine disk 20 , forms a shaft shoulder 24 .
A plurality of balconies 25 ′ 25 ″, 25 ′″, 25 ″″, which extend in the axial direction and are coaxially encircling, are arranged on a side wall 51 , facing the combustion chamber 6 , of the covering element 23 .
In each case three sealing teeth 26 ′, 26 ″, 26 ′″, 26 ″″ extend coaxially on that circumferential surface of each balcony 25 which faces away from the rotor 3 .
Three modules 33 , 34 , 35 are mounted rotationally fixedly on the stator 19 , between the inner wall, located on the radially inner side, of the combustion chamber 6 and the rotor 3 . The rotationally fixed inner ring 30 is provided between the modules 33 , 34 , 35 and the covering element 23 .
On its end side 52 facing the shaft shoulder 24 , the inner ring 30 has a plurality of balconies 29 ′, 29 ″, 29 ′″, 29 ″″ extending in the axial direction and coaxially encircling. Sealing surfaces 27 ′, 27 ″, 27 ′″, 27 ″″ are in each case provided on those circumferential surfaces of the balconies 29 which face the sealing teeth 26 . Each sealing surface 27 , together with its corresponding sealing teeth 26 , forms a labyrinth seal 28 .
A meandering gap 38 , in which therefore four labyrinth seals 28 ′, 28 ″, 28 ′″, 28 ″″ are connected sequentially, of which the three labyrinth seals 28 ′, 28 ″, 28 ′″ are stacked radially on top of one another, is formed between the covering element 23 and the inner ring 30 .
The labyrinth seal 28 ″″ is not stacked radially with respect to the next labyrinth seal 28 ′″ radially inward, but rather is arranged in terraced fashion, i.e. the labyrinth seal 28 ″″ is axially offset with respect to the labyrinth seal 28 ′″.
At its end side 52 facing the combustion chamber 6 , the inner ring 30 has an axially extending arm 46 , on the free end of which a projection 37 , which extends radially inwards, is formed integrally.
On its side facing the inner ring 30 , the module 34 comprises a projection 36 , which forms a hooked engagement with the projection 37 of the inner ring 30 .
When the gas turbine 1 is operating, a working fluid 14 flows within the hot-gas duct 11 . To prevent the working fluid 14 from penetrating as a leakage flow into a gap 38 formed by stationary and rotating components, the gap 38 has a plurality of labyrinth seals 28 which are stacked radially on top of one another and act jointly, in terms of flow, as a seal 31 .
The three labyrinth seals 28 ′, 28 ″, 28 ′″, which are stacked without any axial offset with respect to one another, allow a more compact design combined, at the same time, with an improvement in the sealing action as a result of the increase in the number of labyrinth seals 28 .
FIG. 2 shows an excerpt of a gas turbine 1 located between the hot-gas duct 11 and the axis of rotation 2 of the rotor 3 . The turbine disk 20 ″ bears the rotor blade 18 ″ of the second turbine stage and the turbine disk 20 ′″ bears the rotor blade 18 ′″ of the third turbine stage. On the side wall 22 ″ of the turbine disk 20 ″, the covering element 23 ″ secures the rotor blade 18 ″ against axial displacement. The covering element 23 ″ is hooked to the turbine disk 20 ″ by means of two hooked engagements that are radially spaced apart from one another. In the same way, the covering element 23 ′″ secures the rotor blade 18 ′″ against axial displacement. In this case, the covering element 23 ′″ and the turbine disk 20 ′″ are hooked together on the side wall 22 ′″.
The inner ring 30 with a securing ring 40 is provided in the groove-shaped recess 42 formed between the two turbine disks 20 ″, 20 ′″. The securing ring 40 is connected to the inner ring 30 on its side facing the rotor 3 by means of a hooked engagement 41 and is connected to the guide vane 16 ′″ on its side facing away from the rotor 3 . For this purpose, the inner ring 30 is bolted to the guide vane 16 ′″ by means of a bolt 45 , whereas the securing ring 40 is clamped to the guide vane 16 ′″. The securing ring 40 has a groove 43 into which extends a projection 44 arranged on the guide vane 16 ′″.
The side wall 51 facing away from the turbine disk 20 ′″, the covering element 23 ′″ has three balconies 25 ′, 25 ″, 25 ′″ which extend in the axial direction and are coaxially encircling. In each case three coaxially encircling sealing teeth 26 ′, 26 ″, 26 ′″ are provided on the outer circumference of the individual balconies 25 ′, 25 ″, 25 ′″. On its end side 52 assigned to the turbine disk 20 ′″, the inner ring 30 likewise has three balconies 29 ′, 29 ″, 29 ′″, which extend in the direction of the shaft shoulder 24 and are coaxially encircling transversely with respect thereto. Each balcony 29 , on its inner circumferential surface, has a sealing surface 27 facing the balconies 25 of the covering element 23 ′″ located further inward in the radial direction. In this case, the sealing surface 27 ′ together with the sealing tooth 26 ′ forms a labyrinth seal 28 ′, the sealing surface 27 ″ together with the sealing tooth 26 ″ forms a further labyrinth seal 28 ″, and the sealing surface 27 ′″ together with the sealing tooth 26 ′″ forms the third labyrinth seal 28 ′″.
The seal 31 shown in FIG. 2 can be put together by the sequence of the following assembly steps:
At the start of assembly of the stationary gas turbine 1 having the parting plane 61 , first of all the lower housing half 64 is put in place. In each case the lower halves of the guide vane rings 17 have already been completed in the lower housing half 64 by means of preassembled guide vanes 16 .
Only the covering element 23 ″ has been mounted on the rotor 3 , which has not yet been fitted; the side wall 22 ′″ does not yet have a covering element 23 ′″.
For each inner ring 30 according to the invention, the lower half of the securing ring 40 , which is formed by a single-part or multi-part segment of a total size of 180°, is placed into the lower housing half 64 , so that the projection 44 engages in the groove 43 . Then, the lower half of the inner ring 30 is mounted in the lower housing half 64 which in each case hooks to the inner ring 30 and is partly bolted to the guide vanes 16 in order to secure them against relative movements. The lower half of the securing ring 30 is likewise formed from one or more segments totaling a size of 180°.
When the lower half of each securing ring 40 and inner ring 30 has been mounted in the lower housing half 64 , the rotor 3 is placed into the lower housing half 64 . At least the lower halves of the side wall 22 ′″ of the turbine disks 20 , which subsequently face the end side 52 , must not have a covering element 23 ′″, since otherwise the rotor 3 cannot be placed into the lower housing half 64 .
A segment of the covering element 23 ′″ is mounted on the upper half of the side wall 22 ′″ of the rotor 3 which has already been placed into the lower housing half 64 .
Then, the rotor 3 is rotated, so that during this rotation the segment of the covering element 23 ′″ which is mounted on the upper half is rotated into the lower housing half 64 . In the process, the axially extending balconies 25 of the covering element 23 ′″ move accurately between the corresponding balconies 29 of the inner ring 30 which is already located in the lower half.
Segments of covering elements 23 continue to be mounted on the upper half of the side walls 22 and rotated into the lower housing half 64 until the lower half of the seal 31 has been completely formed.
After the upper half of the covering element 23 has then been mounted on the upper half of the rotor 3 on the side wall 22 ′″, the upper half of the inner ring 30 can then be moved radially inward into the recess 42 formed between the turbine disks 20 ″, 20 ′″ in order to complete the inner ring 30 , in order for the balconies 29 thereof then to be moved over the balconies 25 of the covering elements 23 ′″ by displacement in the axial direction. The upper half of the inner ring 30 is positioned on the flanges of the lower half of the inner ring 30 or securing ring 40 .
Thereafter, the upper half of the securing ring 40 is moved into the recess 42 and hooked to the inner ring 30 in order to complete the circular, segmented securing ring 40 .
Then, in a manner which is already known, the guide vanes 16 of the upper half of the guide vane ring 17 can be mounted.
The assembly instructions are carried out in a similar manner for securing the guide vanes 16 of the first turbine stage 12 shown in FIG. 1 .
In the lower housing half 64 , the guide vanes 16 and the modules 35 , 36 , 37 have already been preassembled before the rotor 3 without covering element 23 is placed into it.
Then, if not already present, one or more segments of the covering element 23 are mounted on the upper half of the side wall 22 of the first turbine disk 20 . Next, the rotor 3 is rotated, so that the segment(s) slide into the lower housing half 64 so as to form the lower half of the seal 31 .
After the upper half of the covering element 23 has been mounted on the upper half of the rotor 3 at the side wall 22 , the upper half of the inner ring 30 can then be moved radially inward into the clear space between turbine disk 20 and annular combustion chamber 6 , in order for the balconies 29 thereof then to be pushed in the axial direction over the balconies 25 of the covering elements 23 . The upper half of the inner ring 30 is located on the end sides of the lower half of the inner ring 30 . Then, the modules 33 , 34 and 36 are successively installed.
In an alternative configuration, each segment can be formed from a plurality of pieces.
During operation, it is possible for the rotor 3 to be displaced counter to the direction of flow of the working fluid 14 without a balcony 25 , 29 touching or striking the end side lying opposite it.
The inner ring 30 , which is rotationally fixed while the gas turbine 1 is operating, together with the rotating covering elements 23 , forms a gap 38 which is sealed by means of the seal 31 . The working fluid 14 is effectively prevented from leaving the hot-gas duct 11 , so that it flows past the rotor blades 18 as intended. The leakage flow is effectively reduced, which leads to an increase in the efficiency of the stationary gas turbine.
Furthermore, the seals 47 , 48 , 49 , 50 reduce the leakage flow between rotating and stationary components. | The invention relates to a segmented inner ring for holding guide blades. According to the invention, a lateral wall opposing the front side of the inner ring and pertaining to a shaft shoulder formed on the rotor shaft extends radially, and respectively one half of a labyrinth seal is formed on the front side of the inner ring and on the shaft shoulder. The aim of the invention is to apply an arrangement of stacked labyrinth seals, known from airplane turbines, to a stationary gas turbine having a separation plane. To this end, a method is used to mount an inner ring of a gas turbine. The invention also relates to a stationary gas turbine comprising a segmented inner ring. | 5 |
BACKGROUND OF THE INVENTION
This invention relates generally to the construction of sewing machine needles of the type having a butt or clamping portion and an adjoining shank or shaft which terminates in a a point above which an eye is formed, and more particularly to a sewing machine needle of this type wherein a long, thread-guiding channel is formed in one side of the shaft which opens into the needle eye and which also has a cutout portion or chamfer formed in the shank above the eye on the side of the needle shaft opposite to the side in which the thread-guiding channel is formed. Sewing machine needles of this type are known and reference is made in this connection to U.S. Pat. No. 4,037,641.
Generally, a sewing machine needle functions as both a tool and as a thread-guiding element and must penetrate during its life a variety of materials to form millions of stitches transporting the needle thread to the thread loop catching device within a predetermined time and over a certain movement path, so that the thread can be gripped or caught to achieve the necessary interlacing and completion of the sewing cycles.
The materials sewn using such needles are in general conventional textile fabrics which may be textured, knitted materials from natural or synthetic fibers for clothing and lingerie, as well as leather, artificial leather or other synthetic laminated material used in the clothing and shoe industry. Moreover, other types of materials, such as paper, cardboard, synthetic foils, textures, meshes, and fleeces formed of glass, steel and asbestos fibers as well as a multitude of other materials in various combinations and designs can be sewn together by seams on sewing machines by means of needles and needle threads. The reliability and quality of the sewn seams are at least in part determined by the specific characteristics of the materials being sewn. In this connection, the elasticity and resistance to puncturing or penetration of the material being sewn often has a critical influence on the efficacy of the seam.
The most frequently used sewing machine needles for backstitching and chain-stitching machines generally include a shaft terminating at a point with an eye formed therethrough and in which a cutout or chamfer portion is formed above the eye to define an interspace between the needle shaft and a needle thread which runs in an upward direction parallel to the needle shaft, which interspace receives a thread catching device during operation of the machine. In conventional needle construction, depth of the chamfer portion is generally only about 25% of the nominal shaft diameter so that the interspace defined by the chamfer portion alone is not sufficient to assure a reliable penetration of the thread catching device. Moreover, the resistance to buckling of a sewing machine needle of this type is reduced by about 40% as compared to a needle which does not have a cutout or chamfer portion. Accordingly, in order to provide sufficient needle rigidity, especially in the case where the needle is used with a material having a high resistance to penetration, it is often necessary to use heavier needles than would otherwise be required by the thickness of the needle thread.
Conventional sewing needles often have an elongate thread-guiding channel formed therein which merge to the needle eye in which the needle thread runs during machine operation. However, due to production and technical reasons, the depth of the thread-guiding channel in the region directly above the needle eye is generally reduced so that the sewing thread is insufficiently protected at that region.
Moreover, in sewing machine needles which are currently formed using stamping techniques, the depth of chamfer portion is limited for technological reasons to a maximum of 30% of the nominal shaft diameter.
For the above reasons, a thread which is guided through a conventional sewing machine needle and which abuts the needle in a taut condition can be gripped or caught by the thread-catching device with only the greatest unreliability, especially when the needles are below Nm90. In other words, the interspace defined between the needle shaft and the needle thread by the cutout or chamfer portion is by itself insufficient to insure a reliable gripping by the thread-catching device. Accordingly, the space in which the thread-catching device is received must be enlarged through the formation of a loop which occurs during the lifting stroke of the needle. More particularly, after the needle has reached its lower dead center position it begins an upward stroke corresponding to a certain crank angle of the drive shaft. In this manner, a loop is formed at the needle whose size is determined at the angle through which the crank rotates during the upward stroke and thereby creating an interspace of a varying magnitude. For example, the interspace will remain relatively small if a highly elastic sewing thread is used in the sewing operation.
However, the angle through which the crank rotates during the loop formation step is relatively small and always occurs after the needle has reached the bottom dead center position of its stroke. These conditions impose severe limits on the construction and coupling of the mechanical functions of the machine which are determined by the kinematics of the sewing thread.
The production techniques presently utilized in the construction of conventional sewing machine needles in which cutout or chamfer portions are produced is constituted by a stamping process which necessarily results in the formation of burrs. Such techniques increase the number of necessary operations thereby increasing production costs as well as material losses whereby the quality of the needle is often insufficient.
SUMMARY OF THE INVENTION
Accordingly, one object of the present invention is to provide a new and improved sewing machine needle having a deeper cutout or chamfer portion and yet which has sufficient resistance to buckling, thereby increasing the interspace between the needle shaft and the sewing thread.
Another object of the present invention is to provide a new and improved sewing machine needle of the above-mentioned type in which the thread-guiding channel has a greater depth in the area where it merges into the needle eye so that the needle thread is completely protected in that region.
Briefly, in accordance with the present invention, these and other objects are attained by providing a sewing machine needle including a shank or shaft in which a chamfer portion is formed and wherein the chamfer portion is defined by a portion of the shaft situated above the needle eye and which is laterally displaced with respect to the axis of the needle and which extends substantially parallel to the needle axis and wherein the displaced shaft portion has substantially the same transverse cross-sectional configuration as other portions of the shaft. Shaft transition portions adjoin the displaced shaft portion and are inclined towards the needle axis.
A sewing machine needle constructed in accordance with the present invention results in an enlargement of the interspace between the needle shaft and the sewing thread such that the sewing thread can be gripped by the thread-catching device in a dependable and reliable manner even without the so-called loop or lifting stroke. It has been surprisingly found that the displacement of the chamfer portion forming shaft portion, which abuts directly on the needle eye, by about 50%, for example, of the nominal shaft diameter or shaft thickness will cause the buckling resistance of the needle to decrease to a lesser extent than the decrease in buckling resistance resulting in conventional needle constructions by cutouts or chamfer portions having a depth of only 25% of the nominal shaft diameter.
In a preferred embodiment of the invention, the amount of displacement of the displaced portion corresponds to about 30% to 60% of the shaft thickness and the longitudinal center lines of the transition portions extend at an angle of less than about 30° to the needle axis. The longitudinal center line of the transition portion adjoining the needle eye preferably extends at an angle of between about 10° and 30° with respect to the needle axis while the longitudinal center line of the upper transition portion extends at an angle of between about 5° and 20° to the needle axis. It has been discovered that no difficulties arise when transition portions with such inclinations or slopes are utilized even at relatively great sewing speeds and that the puncture holes formed in the material being sewn are hardly enlarged, even when such material is relatively inflexible or tough.
As a result of the needle according to the present invention described above, a thread-guiding channel formed on the side of the needle shaft opposite to the side in which the chamfer portion is formed can have a constant depth and yet become deeper at the lower transition portion of the shaft up to the region where the channel merges with the needle eye. This feature advantageously provides a reliable protection for the thread even at the region where the thread-guiding channel merges into the needle eye.
According to the present invention, a rounded upper flange defining the top of the needle eye is somewhat displaced in the direction of a side of the needle shaft in which the chamfer portion is formed, i.e., towards the thread-catching device. This results in an improvement of the guidance of the thread as well as an increase in the interspace between the thread and the shaft.
The upper flange forming the top of the eye as well as the lower end of the thread-guiding channel is shaped in a manner such that it forms, together with a lower flange forming the lower side of the needle eye, a channel which reduces the extent to which the needle thread is deflected in the direction of the needle axis during machine operation.
Further in accordance with the present invention, the sewing machine needle including its pre-formed eye, is produced utilizing an extrusion molding technique, without burr formation and using a blank with specially designed tools whereby the cross-section of the shaft is either V- or U-shaped and whereby the angular position of the side walls along the length of the shaft, including the eye, may be either constant or variable. The molded V- or U-shaped shaft profiles will therefore have no interruptions in the fibers in the cross-section of the material as would otherwise occur in other methods of construction, such as free cutting methods. Accordingly, this method of construction advantageously contributes to the increase of the rigidity of the needle.
DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which:
FIG. 1 is a side elevation view in partial section of a prior art sewing needle and a pre-stressed needle thread associated therewith;
FIG. 2 is a view similar to FIG. 1 and illustrating a sewing needle according to the present invention;
FIG. 3 is a side elevation view in section of the shaft of the prior art needle illustrated in FIG. 1;
FIGS. 3a-3c are sectional views taken along lines A--A, B--B and C--C in FIG. 3;
FIG. 4 is a side elevation view section of the shaft of a needle in accordance with the present invention illustrated in FIG. 2;
FIGS. 4a-4c are sectional views taken along lines D--D, E--E and F--F of FIG. 4;
FIGS. 4a'-4c ' are sectional views similar to those illustrated in FIGS. 4a-4c and illustrating a V-shaped cross-section of a needle in accordance with the present invention;
FIG. 5 is a schematic view of the interspace provided by a prior art needle and the thread-catching device operatively associated with the needle and illustrates the extremely limited time period for the thread-catching operation of the device;
FIG. 6 is a schematic view of the interspace provided by a needle constructed in accordance with the present invention and a thread-catching device operatively associated therewith and illustrates the increase in the time period over which the thread-catching operation can be accomplished relative to the prior art;
FIG. 7 is a side elevation view in section of a needle shaft of a second embodiment of a needle according to the present invention having a second thread-guiding channel;
FIG. 8a is a section view taken along line G--G of FIG. 7;
FIG. 8b is a view similar to FIG. 8a and illustrating a modified embodiment thereof; and
FIG. 9 is a side elevation view in partial section of yet another embodiment of a sewing machine needle constructed in accordance with the present invention and having an arcuate needle axis.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings wherein like reference characters designate identical or corresponding parts throughout the several views, and more particularly to FIGS. 1 and 3, a conventional sewing machine needle such as that disclosed in U.S. Pat. No. 4,037,641, is illustrated of the type which is used in home sewing machines as well as in industrial machines. Such sewing machine needles are generally manufactured utilizing a stamping process which results in the formation of burrs. The prior art sewing needle has an upper clamping or butt portion 1' and an adjoining shank or shaft 2' integrally connected to and extending from an end of the butt portion 1'. The shaft 2' terminates in a needle point 3' and has an eye 4' formed therethrough above the point. In order to protect the needle thread during the stitching of the goods being sewn, a thread-guiding channel 5' is formed on one side of the shaft 2' which merges at its lower end into the eye 4'. On the side of shaft 2' opposite to the side in which the thread-guiding channel 5' is formed, a cutout or chamfer portion 6' is formed above the eye 4'. As seen in FIG. 1, the chamfer portion 6' defines a free space or interspace between the shaft 2' and a relatively taut needle thread.
In conventional sewing machine needles of the type illustrated in FIGS. 1 and 3, the chamfer portion 6' as well as the eye 4' is stamped into the shaft 2' by means of a burr-producing stamping operation. During this process, material from the shaft is forced from the subsequently formed chamfer portion 6' into two lateral burrs situated on a center line of the needle shaft, such as is shown by the dash lines in FIGS. 3b and 3c. These burrs are ground down after the needle has been removed from the stamping mold. Thus, the material volume of the needle shaft is reduced by the volume of the lateral burrs in the region of the chamfer portions 6'. Moreover, the cross-section of the shaft is significantly flattened and reduced in the area of chamfer portion 6' thereby significantly reducing the resistance to buckling of the prior art needle 1'.
The sewing machine needle and associated needle thread are illustrated in FIG. 1 during the puncturing operation and with the needle 1' reaching the dead center position. The protection of the sewing thread afforded by the thread-guiding channel 5' of the prior art needle 1' has proven to be insufficient, particularly in the case of heavier sewing threads. Similarly, the free space or interspace between the needle shaft 2' and the sewing thread, provided by the chamfer portion 6', is too small to allow a reliable gripping of the thread by the thread-catching device without additional widening of the thread loop through the loop forming stroke.
Still referring to FIGS. 1 and 3, the depth of the thread-guiding channel 5' at the point where it merges into the eye 4' is greatly reduced for production and technical reasons. Accordingly, protection of the thread and especially of somewhat heavier sewing threads, is not assured in this region when stitching holes are formed. Thus, during the puncturing of the material, it is possible that sensitive, texturized materials may be torn or that a sewing thread having low rigidity will be sheared as a result of a portion of the sewing thread projecting outwardly from the outer contour of the needle shaft 2'. Moreover, a cutting or milling of the thread-guiding channel 5' so as to have a constant depth is not possible since this would result in the formation of a sharp edge at the point where the thread-guiding channel 5' merges into the eye 4' prior to the return or deflection of the thread around the upper flange 12' (FIG. 3) of needle eye 4' with consequent damage to the needle thread from such a sharp edge. Moreover, it is not feasible to machine finish such a sharp edge for economic reasons.
Furthermore, it is not possible due to the stamping technique utilized in the manufacture of the prior art needle to have the thread-guiding channel 5' merge into the needle eye 4' with a constant depth greater than the diameter of the thread in the region of the eye 4' and of the chamfer portion 6' which has been stamped into the needle shaft by the burr-producing stamping process.
The guidance and formation of the thread loop is accomplished in part by the flange 12' which constitutes the upper side of the eye 4'. The lifting and supporting of the thread loop is accomplished in part by a flange 13' which forms the lower side of eye 4' proximate to the needle point 3'. Thus, flanges 12' and 13', together with the side walls, define the needle eye 4' and are arranged symmetrically with respect to the needle axis 7'. This construction contributes to the fact that a thread loop 20' (FIG. 5) is formed on both sides of the eye 4' when the needle is lifted from its bottom dead center position.
To facilitate a direct comparison with the conventional sewing machine needle illustrated in FIGS. 1 and 3, a sewing machine needle constructed in accordance with the present invention is illustrated in FIGS. 2 and 4. As in the case of the conventional needle 1', the needle 1 of the present invention includes a clamping or butt portion 1 and an adjoining shank or shaft 2 which terminates in a needle point 3 at its free end. An eye 4 is formed through the shaft 2 above the needle point 3 into which a thread-guiding channel 5, formed within the shaft 2, merges. A cutout or chamfer portion 6 is formed on the side of shaft 2 opposite to the side in which the thread-guiding channel 5 is formed.
According to the invention, the chamfer portion 6 is defined by a portion 8 of shaft 2 situated above the needle eye 4 which is laterally displaced with respect to the needle axis 7 which extends substantially parallel thereto. The displaced shaft portion 8 has substantially the same transverse cross-sectional configuration as other portions of shaft 2 above needle eye 4 as best seen in FIGS. 4a and 4b.
A pair of upper and lower transition portions 9 and 10 are formed in shaft 2 which are inclined towards the needle axis 7. Thus, the lower shaft transition portion 10 extends between the region of the needle eye 4 and the lower end of the displaced shaft portion 8 while the upper shaft transition portion 9 extends between the main portion of shaft 2 and the upper end of the displaced shaft portion 8. It has been found that the resistance moment in the displaced shaft portion 8 as well as in the shaft transition portions 9 and 10, is essentially equal to the resistance moment in the region of shaft 2 which adjoins the insertion or butt portion 1 of the needle. Thus, the sewing machine needle manufactured according to the present invention provides complete protection and free mobility for the tightening of the needle thread during the stitching operation.
Moreover, by providing that the shaft 2 at the upper end of eye 4 extends at an angle between about 10° and 30° from the needle axis 7, i.e., that the longitudinal axis of transition portion 10 forms an angle of between about 30° and 10° with needle axis 7, it becomes possible to provide for an increasing depth of the thread-guiding channel 5 at the region at which it merges into the eye 4 while maintaining a constant depth over the remainder of channel 5. Therefore, it is now possible to utilize sewing threads which are two-to-three thicknesses heavier than the threads which could be used with conventional sewing machine needles of the same size and yet afford complete protection thereof during the sewing operation.
Referring to FIGS. 4a and 4b, the shaft 2 of the sewing needle of the present invention has a transverse cross-section which is substantially U-shaped and in the region 4 defines a pair of parallel side walls 14 as seen in FIG. 4c. The web 17 which interconnects the two shanks 16 defining the U-shaped cross-section becomes somewhat wider towards the needle eye 4 so that the side walls 14 in the eye region will protrude on both sides above the peripheral line of the shaft cross-section.
As seen in FIGS. 4a'-4c', the cross-section of the shaft 2 may also have a substantially V-shaped configuration. In this case, the material forced from the needle eye 4 will be pressed into the side walls 14 which are somewhat wider than the thickness of the shaft 2.
It can be seen in FIGS. 4a-4c and 4a'-4c' that the ratio of shaft height to shaft width (H/S) is substantially constant for the three cross sections D,E and F in FIG. 4, which isn't the case for the prior art needle shown in FIGS. 3a-3c. This similarity in H/S ratio provides for a higher resistance to buckling than for the prior art needle as well a better loop formation during sewing.
As a result of the particular profiling of the chamfer portion 6 according to the present invention, which provides for a constant profile force which requires only a minor reduction of the width of the shaft profile only for special requirement, the needle of the invention has excellent rigidity characteristics, even where the depth of the chamfer portions 6 exceeds 60% of the nominal shaft diameter or shaft thickness. In order to assure the gripping of the needle thread, the depth of the chamfer portion 6 shculd be on the order of 50% of the thickness of the shaft 2 or 1.5 to 2 times the diameter of the sewing thread.
As illustrated in FIGS. 7, 8a and 8b, the sewing machine needle of the invention may be provided with a second thread-guiding channel 18 located above the chamfer portion 6 and on the same side thereof. Such construction is particularly advantageous for certain chain-stitching machines and "overlock" sewing machines.
The needle axis 7 of the sewing machine needle according to the present invention may also be curved in an arcuate configuration as seen in the embodiment of the invention illustrated in FIG. 9. If the radius of curvature of the needle axis is relatively large, a sufficient free space is provided for the thread-catching device through the chamfer portion 6.
Referring now to FIG. 5, the thread-gripping or catching operation normally encountered in sewing machines which utilize conventional sewing machine needles is illustrated. The known sewing machine needle has a chamfer portion 6' (FIG. 1) whose depth ranges from about 20% to a maximum of 30% of the thickness of the needle shaft 2'. The gripping or catching of the upper or needle thread by the thread-catching device 19 or by a shuttle is only possible if a thread loop 20' is formed as a result of the lifting of the needle. Thus, only if the crank 21 which drives needle shank 22 has passed the lower dead center position an angle α of at least 10° may the thread-catching device 19 engage the thread loop 20', at the earliest. This condition is illustrated by the right-most illustration of the needle and thread-catching device 19. As the crank continues to rotate through the angle β, which is approximately 15°, the thread loop 20' is further enlarged as depicted by the left-most illustration of the needle shaft 2'. It is therefore seen that only a relatively small crank angle β is available during which the upper or needle thread can be caught by the thread-catching device 19 or similar loop catcher. Moreover, this angle becomes even considerably smaller in the case where an elastic needle thread is used. The construction of the sewing needle of the present invention advantageously permits a significant widening of the crank angle during which the needle thread can be caught relative to prior art constructions. More particularly, referring to FIG. 6, it is indicated that utilizing a needle according to the present invention, the needle thread can be gripped in a "prestressed" condition. The free space or interspace created by the chamfer portion 6 is available at the lower dead center location of the needle and even before the lower dead center position of the needle (approximately a 20° crank angle), sufficient for a reliable gripping of the needle thread without the necessity of widening this space through the lifting of the needle to form a thread loop. As a result, the crank angle through which the needle thread can be caught by the thread-catching device 19 is widened to β, which is approximately 40° of crank angle rotation, wherein about 20° of such crank angle lies prior to the lower dead center position of the crank. Thus, prior to reaching the lower dead center position, the interspace of the thread loop 20 remains constant while after the lower dead center position has been passed, the thread loop 20 widens. Because of this free thread mobility into and through the needle of the invention, the thread loop 20 is greater than the thread loop 20' of the conventional needle, assuming all other factors to be the same. This permits the utilization of larger thread catching devices with adjustable tolerances which is a significant advantage relative to conventional apparatus. The free thread movement through the needle accomplished by the present invention also facilitates the adjustment of a low thread tension at the sewing machine.
The production costs for the needle of the invention are lower than the costs of known production techniques since in the former case the extrusion molding technique utilized to accomplish a direct profiling, i.e., a profiling from a blank by means of a stamping operation to a finished or completely formed needle which requires only the provision of a point for completion. Additionally, material costs are lower as a result of the loss free shaping technique. Because of the increased rigidity and the modified coordination of the individual needle thicknesses for larger thread thicknesses, the current series of needle thicknesses can be reduced from an average of 8 per needle type to approximately 1/2 that number.
The needle construction of the present invention advantageously provides an improved protection for the sewing thread, the functionally critical adjustment tolerance between the needle and the thread-catching device is enlarged and the interdependent time periods to accomplish certain operations are also increased to such an extent that effective improvements for the sewing machine construction and the application of the sewing needle become possible. Additionally, the production technique for the sewing needle of the present invention is improved in a manner such that necessary construction characteristics which improve the quality of the needle can be provided in an economical fashion.
The enlargement or increase of the depth of the chamfer portion above the needle eye makes it possible to completely eliminate the loop lifting step in sewing machines and to control the thread-catching device or, respectively, gripping device in a manner such that its point engages the thread even before the needle has reached its lower dead center position. Thus, the free space which comes into existence between the needle shaft and a taut thread will always be sufficiently large that the gripping point of the thread can be reliably caught over a relatively wide range of crank angles. This interspace is also independent of the material from which the sewing thread is formed, i.e., independent of whether an elastic sewing thread is being used and is also independent of the condition as to whether the upper thread and, if necessary, the lower thread is being sewn under relatively great tension.
All of the advantageous benefits of the present invention makes it possible to considerably increase the sewing speed, to considerably simplify the construction of a sewing machine, eliminate control problems, reduce stitching time, and enable the use of elastic threads under greater tension as well as sewing threads having relatively low rigidity for sewing at higher speed.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the claims appended hereto, the invention may be practiced otherwise than as specifically disclosed herein. | A sewing machine needle has a chamfer portion formed in its shaft which defines an interspace between the needle shaft and a thread running in an upward direction parallel to the needle shaft to permit a thread loop catching device to enter into the interspace during machine operation. The chamfer portion is formed by a portion of the needle shaft which is displaced with respect to the axis of the needle which extends substantially parallel thereto and yet which has substantially the same transverse cross-section as other portions of the shaft and by shaft transition portions which adjoin the displaced shaft portion which extend at an angle with respect to the needle axis. In this manner, a deep chamfer portion is obtained so as to increase the interspace between the needle shaft and sewing thread so that a reliable engagement of the sewing thread by the thread loop catching device can be achieved without the necessity of a so-called loop stroke. Moreover, sufficient resistance to buckling of the needle is achieved despite the increase in depth of the chamfer portion. | 3 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to nip presses used to exert pressing forces on moving webs for the formation of, for example, paper, textile material, plastic foil and other related materials. In particular, the present invention is directed to methods and apparatus for measuring and removing the effects of rotational variability from the nip pressure profile of nip presses which utilize imbedded sensors in covered rolls. While prior art presses which utilize rolls with imbedded sensors may be capable of detecting variations in pressure along the length of the roll, these same imbedded sensors may not be capable of measuring and compensating for rotational variability that can be generated by the high speed rotation of the covered roll. The present invention provides a method and apparatus for measuring and removing rotational variability from the nip pressure profile of the covered roll so as to obtain a more true profile of the nip pressure being developed in the nip region.
[0002] Nipped rolls are used in a vast number of continuous process industries including, for example, papermaking, steel making, plastics calendering and printing. The characteristics of nipped rolls are particularly important in papermaking. In the process of papermaking, many stages are required to transform headbox stock into paper. The initial stage is the deposition of the headbox stock, commonly referred to as “white water,” onto a paper machine forming fabric, commonly referred to as a “wire.” Upon deposition, the a portion of the white water flows through the interstices of the forming fabric wire leaving a mixture of liquid and fiber thereon. This mixture, referred to in the industry as a “web,” can be treated by equipment which further reduce the amount of moisture content of the finished product. The fabric wire continuously supports the fibrous web and advances it through the various dewatering equipment that effectively removes the desired amount of liquid from the web.
[0003] One of the stages of dewatering is effected by passing the web through a pair or more of rotating rolls which form a nip press or series thereof, during which liquid is expelled from the web via the pressure being applied by the rotating rolls. The rolls, in exerting force on the web and fabric wire, will cause some liquid to be pressed from the fibrous web. The web can then be advanced to other presses or dry equipment which further reduce the amount of moisture in the web. The “nip region” is the contact region between two adjacent rolls through which the paper web passes. One roll of the nip press is typically a hard steel roll while the other is constructed from a metallic shell covered by a polymeric cover. However, in some applications both roll may be covered. The amount of liquid to be pressed out of the web is dependent on the amount of pressure being placed on the web as it passes through the nip region. Later rolls in the process at the machine calender are used to control the caliper and other characteristics of the sheet. Covered rolls are at times used at the calender. The characteristics of the rolls are particularly important in papermaking as the amount of pressure applied to the web during the nip press stage can be critical in achieving uniform sheet characteristics.
[0004] One common problem associated with such rolls can be the lack of uniformity in the pressure being distributed along the working length of the roll. The pressure that is exerted by the rolls of the nip press is often referred to as the “nip pressure.” The amount of nip pressure applied to the web and the size of the nip can be important in achieving uniform sheet characteristics. Even nip pressure along the roll is important in papermaking and contributes to moisture content, caliper, sheet strength and surface appearance. For example, a lack of uniformity in the nip pressure can often result in paper of poor quality. Excessive nip pressure can cause crushing or displacement of fibers as well as holes in the resulting paper product. Improvements to nip loading can lead to higher productivity through higher machine speeds and lower breakdowns (unplanned downtime).
[0005] Conventional rolls for use in a press section may be formed of one or more layers of material. Roll deflection, commonly due to sag or nip loading, can be a source of uneven pressure and/or nip width distribution. Worn roll covers may also introduce pressure variations. Rolls have been developed which monitor and compensate for these deflections. These rolls generally have a floating shell which surrounds a stationary core. Underneath the floating shell are movable surfaces which can be actuated to compensate for uneven nip pressure distribution.
[0006] Previously known techniques for determining the presence of such discrepancies in the nip pressure required the operator to stop the roll and place a long piece of carbon paper or pressure sensitive film in the nip. This procedure is known as taking a “nip impression.” Later techniques for nip impressions involve using mylar with sensing elements to electronically record the pressures across the nip. These procedures, although useful, cannot be used while the nip press is in operation. Moreover, temperature, roll speed and other related changes which would affect the uniformity of nip pressure cannot be taken into account.
[0007] Accordingly, nip presses were developed over the years to permit the operator to measure the nip pressure while the rolls were being rotated. One such nip press is described in U.S. Pat. No. 4,509,237. This nip press utilizes a roll that has position sensors to determine an uneven disposition of the roll shell. The signals from the sensors activate support or pressure elements underneath the roll shell, to equalize any uneven positioning that may exist due to pressure variations. The pressure elements comprise conventional hydrostatic support bearings which are supplied by a pressurized oil infeed line. The roll described in U.S. Pat. No. 4,898,012 similarly attempts to address this problem by incorporating sensors on the roll to determine the nip pressure profile of a press nip. Yet another nip press is disclosed in U.S. Pat. No. 4,729,153. This controlled deflection roll further has sensors for regulating roll surface temperature in a narrow band across the roll face. Other controlled deflection rolls such as the one described in U.S. Pat. No. 4,233,011, rely on the thermal expansion properties of the roll material, to achieve proper roll flexure.
[0008] Further advancements in nip press technology included the development of wireless sensors which are imbedded in the sensing roll covers of nip presses as is disclosed in U.S. Pat. Nos. 7,225,688; 7,305,894; 7,392,715; 7,581,456 and 7,963,180 to Moore et al. These patents show the use of numerous sensors imbedded in the roll cover, commonly referred to as a “sensing roll,” which send wireless pressure signals to a remote signal receiver. U.S. Pat. No. 5,699,729 to Moschel discloses the use of a helical sensor for sensing pressure exhibited on a roll. Paper machine equipment manufacturers and suppliers such as Voith GmbH, Xerium Technologies, Inc. and its subsidiary Stowe have developed nip presses which utilize sensors imbedded within the sensing roll cover. These nip press generally utilize a plurality of sensors connected in a single spiral wound around the roll cover in a single revolution to form a helical pattern. An individual sensor is designed to extend into the nip region of the nip press as the sensing roll rotates. In this fashion, the helical pattern of sensors provides a different pressure signal along the cross-directional region of the nip press to provide the operator with valuable information regarding the pressure distribution across the nip region, and hence, the pressure that is being applied to the moving web as it passes through the nip region.
[0009] Control instrumentation associated with the nip press can provide a good representation of the cross-directional nip pressure (commonly referred to as the “nip pressure profile” or just “nip profile”) and will allow the operator to correct the nip pressure distribution should it arise. The control instruments usually provide a real time graphical display of the nip pressure profile on a computer screen or monitor. The nip profile is a compilation of pressure data that is being received from the sensors located on the sensing roll. It usually graphically shows the pressure signal in terms of the cross-directional position on the sensing roll. The y-axis usually designates pressure in pounds per linear inch while the x-axis designates the cross-directional position on the roll.
[0010] While a single line of sensors on the sensing roll may provide a fairly good representation of nip pressure cross-directional variability, these same sensors may not properly take into account the variability of pressure across the nip region caused by the high speed rotation of the sensing roll. The dynamics of a cylinder/roll rotating at a high angular speed (high RPMs) can cause slight changes to the pressure produced by the cylinder/roll that are not necessarily detectable when the cylinder/roll is at rest or rotating at a low speed. Such dynamic changes could be the result of centrifugal forces acting on the cylinder/roll, roll flexing, roll balance, eccentric shaft mounting or out-or round rolls and could possibly be influenced by environmental factors. The dynamic behavior of a typical high speed rotating cylinder/roll is often characterized by a development of an unbalance and bending stiffness variation. Such variations along the cylinder/roll are often referred to as rotational variability. Unbalance can be observed as a vibration component at certain rotating frequencies and also can cause unwanted bending of the flexible cylinder/roll as a function of the rotating speed. Since the lengths of the sensing rolls used in paper manufacturing can be quite long, unbalance in the rotating rolls can pose a serious problem to the paper manufacturer since a less than even nip pressure profile may be created and displayed by the control equipment. Any unwanted bending of the sensing roll can, of course, change the amount of pressure being exerted on the web as it travels through the nip roller. Again, since even nip pressure is highly desired during paper manufacturing, it would be highly beneficial to correctly display the nip pressure profile since any corrects to be made to the rotating roll based on an inaccurate nip pressure profile could certainly exacerbate the problem. A single sensor located at an individual cross-directional position on the sensing roll may not be able to compensate for the effect of rotational variability at that sensor's position and may provide less than accurate pressure readings. There are three primary measurements of variability. The true nip pressure profile has variability that can be term cross-directional variability as it is the variability of average pressure per cross-direction position across the nip. Each sensor in a single line of sensors may have some variability associated with it that may be calculated as the data is collected at high speed. This particular variability profile represents the variability of the high speed measurements at each position in the single line of sensors. This variability contains the variability of other equipment in the paper making process including the rotational variability of the roll nipped to the sensing roll. The third variability profile is the nip profile variability of multiple sensors at each cross-directional position of the roll. This variability represents the “rotational variability” of the sensing roll as it rotates through its plurality or sensing positions.
[0011] One of the problems of rotational variability is the creation of “high spots” and “low stops” at various locations along the sensing roll. A single sensor located at a cross-directional position where a high spot or low spot is found could provide the processing equipment with an inaccurate pressure reading being developed at that location. This is due to the fact that the overall pressure that is developed at the sensor's location as the roll fully rotates through a complete revolution will be lower that the measured “high spot” reading. Accordingly, a nip pressure profile which is based on the reading of a sensor located at a high or low spot will not be indicative of the average pressure being developed that that location. The processing equipment, in relying on this single, inaccurate reading, will calculate and display a nip pressure profile which is at least partially inaccurate. If a number of single sensors are located at numerous high or low spots, then the processing equipment will display a nip pressure profile which has numerous inaccuracies. The operator of the papermaking machinery may not even be aware that the processing system is displaying an inaccurate nip pressure profile. Further, attempts to correct the sensing roll based on an inaccurate nip pressure profile could lead to even greater inaccuracies.
[0012] Therefore, it would be beneficial if the manufacturer could detect and measure any rotational variability along the length of the covered roll of a nip press and compensate for it when a real time nip pressure profile is being calculated and displayed. The present invention provides a better measurement of the true nip pressure profile and is also capable of providing a previously unmeasured nip profile variability of the rotation (rotational variability). Furthermore, certain arrangements of sensing elements will provide information on the wear of the cover. Compensation for any rotational variability should produce a nip pressure profile which is a more accurate representation of the pressure being developed along the nip region of the press. The present inventions satisfy these and other needs.
SUMMARY OF THE INVENTION
[0013] The present invention provides apparatus and methods for accurately detecting, measuring and at least partially removing any effects of rotational variability from a covered roll (also referred to as a “sensing roll”) used in nip presses. The present invention compensates for this effect allowing a more accurate display of the nip pressure profile to be calculated and displayed. The present invention thus provides the machine operator with a more accurate representation of the actual pressure distribution across the nip press. The present invention could be used in collaboration with correcting instrumentation which can eliminate or compensate for pressure variability at locations across the sensing roll of the press. The data obtained from the arrangement of sensors along the sensing roll allows for the calculation and display of a rotational variability profile which can provide the operator with additional real time information concerning the dynamics of the pressure readings in order to obtain a more accurate nip pressure profile. The present invention can compensate for rotational variability in the sensing mechanism by calculating, for example, an average pressure value at each cross-directional (“CD”) position along the sensing roll. The present invention also could calculate and obtain a more accurate nip pressure profile utilizing other models, such as curve fitting.
[0014] The present invention uses multiple sensors circumferentially spaced at various cross-directional positions along the sensing roll in order to cancel the effects of rotational variability which may, or may not, be acting on the sensing roll. These strategically-placed sensors are designed to measure the pressure being placed against the web that is being advanced through the nip press. Previous work has demonstrated that roll rotational variability principally occurs at 1 times the rotational frequency of the roll and occasionally at 2 times the rotational frequency, primarily near the edges of the roll. Higher frequencies are rarely seen and then normally only at the extreme edges of the roll. In additional, cycles at each cross-directional position may be in phase where the highs and lows occur simultaneously across the entire roll width (known as “barring”) or the phasing of the highs and lows may vary across the roll as it rotates. Analysis of these variability patterns has demonstrated that the average of measurements of two sensors spaced 180° circumferential apart at a cross-directional position of a covered roll should provide a good measurement of the actual pressure being developed and would cancel, or at least partially cancel, any rotational variability of 1 times the rotational frequency that might develop at this position. Similarly the average of measurements of three sensors spaced 120° or four sensors spaced 90° circumferential apart at a cross-directional position of a covered roll should provide a good measurement of the actual pressure being developed and would cancel, or at least partially cancel, any rotational variability of 2 times the rotational frequency that might develop at this position. Alternate positioning of multiple sensors to remove the effect of rotation is possible. In this manner, a more true measurement of the pressure distribution across the nip region should be obtainable. Information on higher frequency barring which is indicative of cover wear and has been seen at calender stacks may be obtained by spacing the sensing elements at different rotational positions. The difference between individual sensing elements and the average of the group of sensing elements at the same cross-direction progression provides a measure of the roundness of the roll and shape of the cover. The progression of this difference as the cover ages is an indicator of cover wear.
[0015] The present invention provides advantages over sensing rolls and system which utilize a single sensor assigned to measure the pressure at a particular cross-directional position. Sensing rolls which just utilize a single sensor disposed at a cross-directional position on a roll lack the ability to take secondary measurements at the same cross-directional position for purposes of comparison to determine if there is any unbalance at that particular cross-directional position. As a result, such a sensing roll may provide inaccurate readings for calculating and displaying the nip profile. If the single sensor is placed at a position where there is a high or low spot, caused by rotational imbalance, then that sensor's pressure reading will not be quite accurate and its reading would lead to the calculation of an inaccurate nip pressure profile. Additionally, the use of single sensors at each CD position cannot generate the necessary data to allow for the calculation and display of a rotational variability profile which could provide the operator with additional real time information in order to obtain a more accurate nip pressure profile. The present invention allows for the calculation and display of such a rotational variability profile, along with the nip pressure profile.
[0016] In one aspect, the sensing roll for use in a nip press includes strategically-placed sensors including a first set of sensors disposed in a particular configuration along a roll cover that overlies a cylindrical member. Each sensor of this first set is located at a particular lateral position (cross-directional position) on the roll cover. The sensing roll further includes additional sets of sensors which are likewise disposed in a particular configuration on the roll cover, each sensor of the second set being likewise disposed at a particular cross-directional position. Each sensor of the first set of sensors has a corresponding sensor in the additional sets to define the CD group of sensors that are utilized to take the pressure readings at a particular cross-directional position. Again, each sensor at the cross-directional position is spaced circumferentially apart from the other. Multiple corresponding sensors can be strategically placed at different cross-directional positions along the length of the sensing roll, each pair of sensors designed to measure the pressure being developed at that cross-directional position. Each sensor will measure the pressure as it enters the nip region of the press. In theory, each corresponding sensors of a CD group should measure the same pressure at the particular cross-directional position if the sensing roll is truly balanced. If the pressure measurements for the two corresponding sensors are significantly different, then the measurements would indicate some variability that may be caused by the dynamics of the rotating sensing roll. The present invention allows the sensing roll to take multiple, not just one, pressure measurements at each cross-directional position during each 360° revolution of the sensing roll. These multiple measurements are utilized to obtain a more accurate nip pressure profile and a rotational variability profile. In one aspect of the invention, the readings at each sensor can be averaged to determine an average pressure measurement at that particular cross-directional position. This averaged measurement can then be used in computing and displaying the nip pressure profile. The same readings can be used to calculate and display the rotational variability profile of the operating nip press. The variability of the readings at each position will be monitored and displayed to determine if the roll rotational variability is stable or increasing. There are many possible measures of this variability including variance, standard deviation, 2 sigma, percent of process, co-variance, peak to peak. Increasing variability using any measure may be indicative of a potential failure in the bearings or roll cover or other roll problems.
[0017] In another aspect, multiple sets of sensors are disposed so as a particular pattern of lined-up sensors are created. For example, the pattern could be a continuous helical configuration which extends around the sensing roll in one revolution forming a helix around the sensing roll. The sensors of several sets can be aligned in a number of different patterns along the length of the sensing roll in order to develop a good representative nip pressure profile. In another aspect, the continuous line of sensors can extend only partially around the sensing roll, for example, in one half (½) revolution. A second set of sensors would also extend around the sensing roll in one half (½) revolution. In this manner, only a partial helix is formed around the sensing roll 10 . This arrangement of sensors still allows a pair of sensors to be assigned to a particular CD position. These sets of sensors would be spaced 180° circumferential apart from each other. In a similar manner three helixes may be wound 120° each, four 90° each or n helixes 360°/n each. The particular advantage of this arrangement of sensors is in sensing short wavelength bars that may be associated with cover wear as each sensing element is at a different rotational position.
[0018] In another aspect, a system for calculating and displaying a nip pressure profile and rotational variability profile for a nip press includes a sensing roll configured with a second roll in a nip arrangement, the sensing roll and the second roll adapted to rotatingly press matter therebetween in a nip region. The sensing roll has a plurality of cross-directional positions defined along its length. The sensing roll including a first set of pressure-measuring sensors and additional sets of pressure-measuring sensors, each sensor of the plural sets of sensors being disposed at a particular cross-directional position along the sensing roll. Each sensor is configured to sense and measure pressure when the sensor enters the nip region of the nip press. Again, each sensor of the first set has corresponding sensors in the additional sets which are located at the same cross-directional position but are spaced apart circumferentially on the sensing roll to provide multiple pressure readings at each cross-directional position. The plurality of readings can be used to calculate and formulate the nip pressure profile and rotational variability profile for the press. In one aspect, an average pressure reading at each location can be calculated to obtain a more accurate nip pressure profile.
[0019] A transceiver can be attached to the sensing roll and to each of the sensors of the multiple sets for transmitting data signals from the sensors to a receiver unit. A processing unit for calculating the nip pressure distribution based on the pressure measurements of each CD group of corresponding sensors of the first and additional sets of sensors can be coupled to the sensing roll. A display unit also could be coupled to the processing unit to provide a visual display of the nip pressure profile and the rotational variability profile.
[0020] A method for sensing and removing the effects of rotational variability from the nip pressure profile of a sensing roll of a nip press includes providing a sensing roll having a working length and a number of cross-directional positions disposed along the working length. Multiple pressure-measuring sensors are placed at each of the cross-directional positions, the sensors of each cross-directional position being spaced apart circumferentially from each other. The pressure being exerted on each sensor of each CD group as the sensor moves into the nip region of the nip press is then measured with the pressure measurements of each sensor at that cross-directional position being calculate to obtain an average pressure measurement at the respective cross-directional position. The obtained pressure measurements calculated at each cross-directional position can then be utilized to create a nip pressure profile for the nip press.
[0021] In yet another aspect, a method for measuring and removing the effects of rotational variability from the nip pressure profile of a sensing roll of a nip press includes measuring the pressure exerted on a first sensor disposed at a particular cross-directional position on the sensing roll of the nip press as the first sensor enters the nip region of the press. The pressure exerted on additional sensors is also measured as the second sensor enters the nip region of the press. The additional sensors are located at the same cross-directional position as the first sensor but spaced apart circumferentially from the first sensor. The pressure measurements of the multiple sensors are used to calculate and display the nip pressure profile and rotational variability profile. Multiple pluralities of sensors could be placed at various cross-directional positions along the sensing roll in order to measure pressures at multiple offset locations for each cross-directional position. The pressure measurements from the multiple sensors for each cross-directional position are averaged and used to calculate and display the nip pressure profile that is developed across the nip region. The method may include providing corrective procedures to the sensing roll in order to adjust for high or low pressure spots along the nip pressure profile.
[0022] These and other advantages of the present invention will become apparent from the following detailed description of preferred embodiments which, taken in conjunction with the drawings, illustrate by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a perspective view showing a nip press which utilizes a particular embodiment of a sensing or covered roll made in accordance with the present invention.
[0024] FIG. 2 is an end, schematic view of the nip press of FIG. 1 showing the formation of a web nipped between the nip rolls, the nip width of the nip press being designated by the letters
[0025] FIG. 3A is a side elevational view of a particular embodiment of a sensing roll made in accordance with the present invention which shows the placement of two sets of sensors along the length of the roll.
[0026] FIG. 3B is an end view of the sensing roll of FIG. 3A showing the placement of the first and second sets of sensors some 180° apart circumferentially on the sensing roll.
[0027] FIG. 4 is a side elevational view showing the placement of the two lines of sensors along the length of the sensing roll with sensors disposed within the nip region which is designated by a pair of dotted lines.
[0028] FIG. 5 is a side elevational view showing the placement of the two lines of sensors along the length of the sensing roll after the sensing roll has rotated 180° from its initial position shown in FIG. 4 .
[0029] FIG. 6A is a side view of a particular embodiment of a sensing roll made in accordance with the present invention which shows the placement of three sets of sensors along the length of the roll.
[0030] FIG. 6B is an end view of the sensing roll of FIG. 6A showing the placement of the first, second and third sets of sensors some 120° apart circumferentially on the sensing roll.
[0031] FIG. 7A is a side view of a particular embodiment of a sensing roll made in accordance with the present invention which shows the placement of four sets of sensors along the length of the roll.
[0032] FIG. 7B is an end view of the sensing roll of FIG. 7A showing the placement of the first, second, third and fourth sets of sensors some 90° apart circumferentially on the sensing roll.
[0033] FIG. 8A is a side view of a particular embodiment of a sensing roll made in accordance with the present invention which shows the placement of two sets of sensors wound 180° circumferentially along the length of the roll.
[0034] FIG. 8B is an end view of the sensing roll of FIG. 8A showing the placement of the first and second sets of sensors some 180° apart circumferentially on the sensing roll.
[0035] FIG. 9A is a side view of a particular embodiment of a sensing roll made in accordance with the present invention which shows the placement of three sets of sensors wound 120° circumferentially along the length of the roll.
[0036] FIG. 9B is an end view of the sensing roll of FIG. 9A showing the placement of the sets of sensors some 120° apart circumferentially on the sensing roll.
[0037] FIG. 10A is a side view of a particular embodiment of a sensing roll made in accordance with the present invention which shows the placement of four sets of sensors wound 90° circumferentially along the length of the roll.
[0038] FIG. 10B is an end view of the sensing roll of FIG. 10A showing the placement of the sets of sensors some 90° apart circumferentially on the sensing roll.
[0039] FIG. 11 is a schematic drawing showing the basic architecture of a particular monitoring system and paper processing line which could implement the sensing roll of the present invention.
[0040] FIG. 12 is a graphical display showing a plot of normalized error versus profile position for a single sensor array and two sensor array showing a helical pattern of in-phase variability over one cycle.
[0041] FIG. 13 is a graphical display showing a plot of normalized error versus profile position for a single sensor array and two sensor array (180°) showing a helical pattern of out of phase variability over one cycle.
[0042] FIG. 14 is a graphical display showing a plot of normalized error versus profile position for a single sensor array, a two sensor array (180°) and three sensor array (120°) showing a helical pattern of out of phase variability over one cycle/rotation center and 2 cycles/rotation edges.
[0043] FIG. 15 is a graphical display showing a comparison of nip pressure versus profile position for 3 sensor arrays for array 1 (0°), array 2 (90°) and array 3 (180°).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] The present invention relates to rolls for use particularly in nipped roll presses, in which rolls exert pressing forces on webs for forming paper, textile material, plastic foil and other related materials. Although the present invention may be used in the above industries, the discussion to follow will focus on the function of rolls for use particularly in the manufacture of paper and particularly to a nip press for dewatering a fibrous web, comprising a sensing roll disposed so as to rotatingly cooperate with another roll in the nip press. FIGS. 1-5 depict the embodiment wherein two sensors are positioned 180° circumferentially across the width of the roll at each cross-directional location as this provides the simplest illustration. Additional embodiments with multiple sensors at each CD location can be extrapolated, as is shown in FIGS. 6-8B .
[0045] As shown in FIG. 1 , a schematic perspective view shows a sensing roll 10 made in accordance with the present invention as a portion of a nip press 12 which includes a second roll 14 that cooperates with the sensing roll 10 to produce pressure on a fibrous web 16 that is advanced between the two rolls 10 , 14 . The sensing roll 10 and second roll 14 rotate, as is indicated by arrows in FIG. 2 , and are spaced apart at a nip region 18 where the two rolls 10 , 14 somewhat meet in order to place pressure on the fibrous web 16 so as to remove some of the liquid suspended in the web 16 . The letters NW in FIG. 2 indicate the formed “nip width” of the nip region 18 . This nip region 18 extends along the entire cross-directional length of the sensing roll 10 and second roll 14 . The sensing roll 10 may include an inner base roll 20 and the outer roll cover 22 may comprise materials suitable for use in making a press roll. The inner base roll 20 may include one or more lower layers, with the outer roll cover 22 being the top layer. This composite sensing roll 10 with the roll cover 24 is commonly known as a “covered roll” in the industry. The second roll 14 may be an uncovered roll or also comprise of a number of layers of materials and a base roll as well. If multiple covered rolls are contained in the nip, each may have sensors and produce nip profiles and variability profiles. The nip profiles or the two covered rolls may be averaged together for greater accuracy in making nip profile adjustments. However, the variability profiles of each covered roll provide information about the condition of that specific roll. It should be appreciated that while the present embodiments focuses only in a single nip, it is possible to utilize single rolls involved in bi-nip, tri-nip or multi-nip interactions which are common in the paper industry. One two rolls 10 , 14 are depicted to more clearly describe the advantages associated with the present invention. However, multiple nip profiles can be generated with each independent sensing roll utilizes in the nip press.
[0046] Referring now to FIGS. 1 and 3 , a first set 24 of sensors 26 is associated with the sensing roll 10 along with a second set 28 of sensors 30 . Sensors 26 of the first set 24 are designated by a circle while sensors 30 of the second set 28 are designated by a square. Circles and squares have been used for ease in identify the sensors constituting the first set 24 of sensors from the second set 28 of sensors. However, in practice, these sensors 26 and 30 can be the exact same sensing device. Also, one or both of the rolls 10 , 14 may have sensors associated with the roll. For purposes of illustration, however, this discussion will focus on only one of the rolls having sensing and measuring capabilities.
[0047] These sensors 26 and 30 may be at least partially disposed within the roll cover 22 which forms the portion of the sensing roll 10 . Each of the sensors 26 and 30 are adapted to sense and measure a particular data parameter, such as, for example, the pressure that is being exerted on the sensor when it enters the nip region 18 . As can be best seen in FIG. 3A , the first set 24 of sensors 26 is shown disposed in a particular configuration along the sensing roll 10 , each sensor 26 being located at a particular lateral position (referred to as the “cross-directional position” or “CD position”) on the sensing roll 10 . Each cross-directional position is a particular distance from the first end 32 of the sensing roll 10 . As can be seen in the particular embodiment of FIG. 3A , the first set 24 of sensors 26 are disposed along a line that spirals around the entire length of the sensing roll in a single revolution forming a helix or helical pattern. The second set 28 of sensors 30 is likewise disposed along a line that spirals around the entire length of the sensing roll in a single revolution creating the same helix or helical pattern except that this second set 28 of sensors 30 is separated apart from the first set 24 some 180° circumferentially around the sensing roll 10 . FIG. 3B shows an end view of the first set 24 spaced approximately 180° apart from the second set 28 . The use of these two lines of sensors 26 , 30 allows a large amount of the outer surface of the sensing roll 10 to be measured while the roll 10 is rotating. While the particular pattern of the first set 24 and second set 28 is shown herein in a helical pattern around the roll 10 , it should be appreciated that these sets 24 , 28 of sensors can be disposed in other particular configurations to provide pressure measurements all along the sensing roll 10 .
[0048] Each sensor 30 of this second set 28 is disposed at a particular cross-directional position on the sensing roll 10 . Each sensor 26 of the first set 24 has a corresponding sensor in the second set 28 with each corresponding sensor of the first and second set being located at the same cross-directional position along the sensing roll. In this manner, each cross-directional position of the sensing roll has a pair of sensors which measure the pressure at two different circumferential positions. Each pair of corresponding sensors are located along the sensing roll 10 at a cross-directional position to provide two sensor readings when the sensing roll completes a full 360° rotation. The average of these two readings can then be utilized to calculate and display the nip pressure profile that is being developed on the rotating nip press 12 .
[0049] The manner in which the pressure measurements can be made is best explained by referring to FIGS. 4 and 5 . FIGS. 4 and 5 show side elevational views of the sensing roll 10 as it would be viewed looking directly into the nip region 18 which is depicted by a pair of dotted lines. FIG. 4 shows a typical view in which the sensing roll 10 has a pair of sensors 26 , 30 directly in the nip region ready to take a pressure measurement. A grid located at the bottom of the sensing roll 10 for illustrative purposes shows fourteen (14) individual cross-directional positions along the working length L of the sensing roll 10 . In FIG. 4 , the first set 24 of sensors 26 can be seen depicted positioned at cross-directional positions numbered 1 - 7 . Likewise, the second set 28 of sensors 30 are shown in cross-directional positions numbered 8 - 14 in FIG. 4 . The other sensor 26 of the first set 24 are disposed in cross-directional positions 8 - 14 but cannot be seen in FIG. 4 . Likewise, the remaining sensors 30 of the second set 28 are in positions 1 - 7 but cannot be seen in FIG. 4 since they are at the reverse side of the sensing roll. It should be appreciated that only fourteen cross-directional positions are shown in these drawings to provide a simple explanation of the manner in which the present invention operates. In actual operation, there can be many more cross-directional positional positions associated with a sensing roll given the long lengths and widths that are associated with these rolls.
[0050] Only the sensor 26 located in the 4 th cross-directional position and the sensor 30 located in the 11th cross-directional position are in proper position for taking the pressure measurement as they are located in the nip region NR. Once these two sensors 26 , 30 enter the nip region NR, the pressure being exerted on the sensor is measured. As the sensing roll 10 continues to rotate, the other sensors in the 5 th and 12 th cross-directional positions will then be located in the nip region NR and will be able to measure the pressure at these particular positions. Further rotation of the sensing roll 10 places the sensors in the 6 th and 13 th cross-directional positions into the nip region NR for pressure measurements. Eventually, the sensing roll 10 rotates 180° from its initial position shown in FIG. 4 and will again have sensors in the 4 th and 11 th cross-directional positions. This arrangement of sensors 26 , 30 is shown in FIG. 5 . The only difference is that a sensor 30 of the second set 28 is now in the 4 th cross-directional position and a sensor 26 of the first set 24 is in the 11 th cross-directional position. These sensors 26 and 30 shown in FIGS. 4 and 5 are corresponding sensors which read the pressure at the 4 th cross-directional position. Likewise, sensor 26 of the first set 24 in FIG. 5 is now in the 11 th cross-directional position ready to measure the pressure at that location. The sensor 30 in the 11 th cross-directional position shown in FIG. 4 and the sensor 26 in the 11 th cross-directional position of FIG. 5 constitute corresponding sensors which provide pressure readings at that particular location on the sensing roll. The system which processes the pressure measurements can take the average of the readings of each pair of corresponding sensors at a particular cross-directional position and calculate the nip profile at that position based on an average reading. For example, if the sensors 26 , 30 in the 4 th cross-directional position both read 200 lbs per linear inch (PLI) then their average would be 200 PLI. This would indicate that there is little, or no, pressure variation caused by the rotation of the sensing roll 10 . The average 200 PLI reading would then be used to calculate and display the nip pressure profile at that particular cross-directional position. For example, if the sensor 30 in the 11 th cross-directional position, as shown in FIG. 4 , reads 240 PLI and the sensor 26 in the 11 th position shown in FIG. 5 reads 160 PLI, then the average pressure would be 200 PLI. These two different readings at the 11 th cross-directional position would indicate a pressure variation that most likely would be attributed to the high speed rotation of the sensing roll 10 . However, in processing the nip pressure profile for the 11 th cross-directional position, the average pressure measurement of 200 PLI would be utilized since this average will cancel, or nearly cancel, the effect of rotational variability that is occurring along the sensing roll 10 . The average of the two measurements will result in a more accurate representation of the pressure being developed at that particular cross-directional position.
[0051] In prior art sensing rolls which utilize a single sensor at each cross-directional position, the processing unit would have single sensors at each cross-directional positions. A prior art sensing roll which has a single sensor at the 11 th cross-directional position in the illustrated example above could only rely on a single reading at that position in order to calculate and display the nip pressure profile. A prior art roll would then use either the 240 PLI or 160 PLI reading for determining and displaying the nip pressure profile at this location. Such a reading would be less than accurate as the sensing roll full rotates in a 360° revolution. Accordingly, the calculated nip pressure at this position will be less than accurate. However, the processing unit would display a nip pressure profile would appear to be accurate but in reality would be less than accurate. If adjustments are made to the sensing roll by the machine operator or through automatic adjustment equipment to compensate for high or low pressure readings, then the sensing roll could be adjusted to develop even more incorrect pressures at various locations in the nip region.
[0052] As the roll 10 rotates placing different sensors into the nip region, the respective sensors measure the pressure which is then transmitted to the processing unit. The processing unit associated with each sensing roll 10 can then calculate the average pressure of each pair of corresponding sensors at the various cross-directional positions and produce a nip pressure profile which can be visualized on a monitor or other visual screen. Computer equipment well known in the art could be utilized to process the pressure readings that are being made in milliseconds.
[0053] One method of the present invention for sensing and removing the effects of rotational variability from the nip pressure profile of a sensing roll of a nip press thus includes providing a sensing roll having a working length and a plurality of cross-directional positions disposed along the working length and the placement of pairs of pressure-measuring sensors at each cross-directional positions. In the particular embodiment shown in FIGS. 3A-5 , the method utilizes sensors being spaced apart 180° circumferentially from each other. This allows for two different pressure measurements to be made at each cross-directional position. The pressure exerted on each sensor of each pair as the sensor moves into the nip region of the nip press can then be measured and the average of each of the two sensors at each cross-directional position can be calculated to determine an average pressure measurement. The average pressure measurements at each cross-directional position can then be used to provide a nip pressure profile for the nip press.
[0054] It should be appreciated that while the present invention discloses mathematical modeling that utilizes the direct averaging of the measurements taken by each corresponding sensor, it could be possible to obtain a composite average measurement utilizing other types of models which can obtain and calculate an averaged measurement at each cross-directional position. For example, the operating equipment (data processors) could utilize another model such as “curve fitting” which also can provide the more accurate nip pressure profile. Still other models known in the art could be utilized with the multiple pressure readings from the various sensors to obtain the more accurate nip pressure profile.
[0055] Variations of the sensing roll are disclosed in FIGS. 6-8 . Referring initially to FIGS. 6A and 6B , three different sets of sensors are utilized and extend around the sensing roll 10 . As can be seen in the disclosed embodiment of the sensing roll 10 , a first set 24 of sensors 26 , a second set 28 of sensors 30 and a third set 32 of sensors 34 are shown as continuous lines of sensors which extend around the sensing roll in one full revolution, each set 24 , 28 , 32 forming a helix around the sensing roll 10 . Sensors 34 are shown as a triangle to distinguish that particular sensor from the sensors 26 , 30 of the other two sets 24 , 28 . Adjacent sets 24 , 28 and 30 of sensors are spaced 120° circumferential apart from each other (see FIG. 6B ) at a cross-directional position of the sensing roll 10 to provide a good measurement of the actual pressure being developed and would cancel, or at least partially cancel, any rotational variability of 2 times the rotational frequency that might develop at this CD position. Again, the measurements from each of the corresponding sensors at each CD position can be averaged to provide an averaged measurement which provides a more accurate representation of the nip pressure being developed at that CD position.
[0056] It should be appreciated that the working length of the sensing roll can be quite long and may require each set of sensors to be wound more than one times around the roll. Again, such a pattern is satisfactory as long as the pattern allows for three sensors to be use at each cross-directional position (spaced 120° apart) in order to produce three separate pressure readings which are then processed to produce a base reading.
[0057] Referring now to FIGS. 7A and 7B , a fourth set 36 of sensors 38 has been added to the sensing roll 10 to provide yet another sensor at each CD position. Adjacent sets 24 , 28 , 30 , 36 are spaced 90° circumferential apart from each other (see FIG. 7B ) at a cross-directional position of the sensing roll 10 to provide a good measurement of the actual pressure being developed and would cancel, or at least partially cancel, any rotational variability of 2 times the rotational frequency that might develop at this CD position. Again, It should be appreciated that the working length of the sensing roll can be quite long and may require each set of sensors to be wound more than one times around the roll. Such a pattern is satisfactory as long as the pattern allows for four sensors to be use at each cross-directional position (spaced 90° apart) in order to produce four separate pressure readings which are then processed to produce a base reading.
[0058] Referring now to FIGS. 8A and 8B , a first set 24 of sensors 26 is shown as a continuous line of sensors which extend around the sensing roll in one half (½) revolution. Likewise, a second set 28 of sensors 30 extend around the sensing roll in one half (½) revolution. In this manner, only a partial helix is formed around the sensing roll 10 . This arrangement of sensors 26 , 30 still allows a pair of sensors to be assigned to a particular CD position. Like the sensing roll 10 shown in FIGS. 3A-5 , adjacent sets 24 , 28 are spaced 180° circumferential apart from each other (see FIG. 8B ). The resulting structure creates a sensing roll that has only one sensor entering the nip region at any given time. This particular embodiment of the sensing roll 10 should provide a good measurement of the actual pressure being developed and would cancel, or at least partially cancel, any rotational variability of 2 times the rotational frequency that might develop at this CD position.
[0059] In a similar manner three helixes may be wound 120° each, four 90° each or n helixes 360°/n each. The particular advantage of this arrangement of sensors is in sensing short wavelength bars that may be associated with cover wear as each sensing element is at a different rotational position. FIGS. 9A and 9B show three continuous lines 24 , 28 and 32 of sensors 26 , 30 and 34 which extend around the sensing roll in a partial revolution (a 120° revolution). In this manner, only a partial helix is formed around the sensing roll 10 by each set 24 , 28 and 32 . This arrangement of sensors 26 , 30 and 34 allows group of sensors to be assigned to a particular CD position. Like the sensing roll 10 shown in FIGS. 6A and 6B , adjacent sets 24 , 28 and 32 are spaced 120° circumferential apart from each other along the roll (see FIG. 9B ). FIGS. 10A and 10B show four continuous lines 24 , 28 , 32 and 36 of sensors 26 , 30 , 34 and 38 which extend around the sensing roll in a partial revolution (a 90° revolution). Again, only a partial helix is formed around the sensing roll 10 by each set 24 , 28 , 32 and 36 . This arrangement of sensors 26 , 30 , 34 and 38 allows group of sensors to be assigned to a particular CD position. Like the sensing roll 10 shown in FIGS. 7A and 7B , adjacent sets 24 , 28 , 32 and 36 are spaced 90° circumferential apart from each other (see FIG. 10B ). The resulting structure creates a sensing roll that has only one sensor entering the nip region at any given time. This particular embodiment of the sensing roll 10 should provide a good measurement of the actual pressure being developed and would cancel, or at least partially cancel, any rotational variability of 2 times the rotational frequency that might develop at this CD position. Similar lines of sensors could be disposed along the length of the sensing roll 10 such that n lines of sensors forming partial helixes are formed and placed 360°/n along the length of the roll 10 . Adjacent lines of sensors would be spaced 360°/n circumferentially apart from each other along the roll.
[0060] The methods for sensing and removing the effects of rotational variability from the nip pressure profile of a sensing roll of a nip press utilizing the embodiments of FIGS. 6A-10B includes providing a sensing roll having a working length and a plurality of cross-directional positions disposed along the working length and the placement of pairs of pressure-measuring sensors at each cross-directional positions. The method will calculate an average pressure measurement utilizing the number of sensors placed at each CD position. In the embodiments of FIGS. 6A and 6B and FIGS. 9A and 9B , three sensors located a CD position are averaged. Likewise, the readings from the four sensors of the embodiments of FIGS. 7A and 7B and FIGS. 10A and 10B are utilized to produce an average pressure measurement. The embodiment of FIGS. 8A and 8B , like the embodiment of FIGS. 3A-5 , utilize a pair of sensor measurements at each CD position. The average pressure measurements at each cross-directional position can then be used to provide a nip pressure profile for the nip press.
[0061] The sensors used in the various sets can be electrically connected to a transmitter unit 40 which also can be attached to the sensing unit 10 . The transmitter unit 40 can transmit wireless signals which can be received by a wireless receiver located at a remote location. The wireless receiver can be a part of a system which processes the signals, creates the nip profile and sends corrective signals back to the sensing roll 10 . Sensors may be collected in the same collection period and average together for immediate use. However, the additional wireless transmission may reduce the battery life of the wireless unit. As the rotational variability changes slowly, alternating the collection between the sensors and averaging together the collections in the alternate collection periods will provide comparable information and may save battery life.
[0062] One particular system for processing the signals is shown in FIG. 11 and will be discussed in greater detail below. Wireless transmission can be carried out via radio waves, optical waves, or other known remote transmission methods. If a direct wired transmission is desired, slip ring assemblies and other well-known electrical coupling devices (not shown) could be utilized.
[0063] FIG. 11 illustrates the overall architecture of one particular system for monitoring of a product quality variable as applied to paper production. The system shown in FIG. 11 includes processing equipment which calculates and displays the nip pressure profile. For example, the pressure measurements can be sent to the wireless received from the transmitter(s) located on the sensing roll. The signals are then sent to the high resolution signal processor to allow the average pressure measurements to be calculated and utilized to create and display the nip pressure profile. Data can be transferred to the process control which can, for example, send signals back to the sensing roll to correct pressure distribution across the nip region. One such nip press which is capable of real time correction is described in U.S. Pat. No. 4,509,237, incorporated herein by reference in its entirety. This nip press utilizes a roll that has position sensors to determine an uneven disposition of the roll shell. The signals from the sensors activate support or pressure elements underneath the roll shell, to equalize any uneven positioning that may exist due to pressure variations. Other known equipment which can correct the roll cover could also be used.
[0064] The sensors can take any form recognized by those skilled in the art as being suitable for detecting and measuring pressure. Pressure sensors may include piezoelectric sensors, piezoresistive sensors, force sensitive resistors (FSRs), fiber optic sensors, strain gage based load cells, and capacitive sensors. The invention is not to be limited to the above-named sensors and may include other pressure sensors known to those of ordinary skill in the art. It should be appreciated that data relating to the operational parameter of interest, other than pressure, could be utilized with the present invention. In this case, the sensors could be used to measure temperature, strain, moisture, nip width, etc. The sensors would be strategically located along the sensing roll as described above. Depending on the type of sensor, additional electronics may be required at each sensor location. The design and operation of the above sensors are well known in the art and need not be discussed further herein.
[0065] The processor unit is typically a personal computer or similar data exchange device, such as the distributive control system of a paper mill that can process signals from the sensors into useful, easily understood information from a remote location. Suitable exemplary processing units are discussed in U.S. Pat. Nos. 5,562,027 and 6,568,285 to Moore, the disclosures of which are hereby incorporated herein in their entireties.
[0066] Referring now to FIGS. 12-15 , graphical displays are provided which further explains and presents typical mapping of roll variability which can develop during operation. Roll surfaces were mapped pursuant to the methods and apparatus described in U.S. Pat. No. 5,960,374 using paper properties sensors that were related to nip pressure. The mappings used an array of 5,000 elements broken into 100 CD positions and 50 rotational positions. The mappings confirmed that most roll variability occurs in 1 cycle per revolution in-phase across the roll or out-of-phase (the phase shifts with profile position). A 2 cycle per revolution pattern is sometime noted at the edges of the roll. Higher frequencies (such as 3 cycles per revolution) are rarely seen and then only at the extreme edges and have little impact. Three roll surface maps were normalized (scaled on 0-100%) and helical scan paths were superimposed over the surface maps. The true nip pressure profile was determined by averaging the 50 rotational positions at each of the 100 CD positions. The helical scan paths and the averages of two or more of these paths at various separation angles were used to develop estimates of the nip pressure profile. These estimates were then subtracted from the true nip profile to obtain the error in each estimate. FIGS. 12 and 13 demonstrate that two sensor arrays across the width of the roll and separated by 180° circumferentially are sufficient to remove most of the rotational variability when the variability is 1 cycle per revolution. FIG. 14 demonstrates that 2 arrays are not sufficient to handle the 2 cycle per revolution variability at the edges as the estimate difference from the true nip profile is an large at the edges as the single helical scan. For this case a minimum of 3 arrays separated by 120° would be needed. A larger number of arrays per revolution may further reduce the measurement error, but at a higher cost. Therefore, the embodiment of three (3) arrays (lines) of sensors separated by 120° circumferentially insures that all 1 cycle/revolution and 2 cycle/revolution variability is reduced. However, 2 arrays may be sufficient for many rolls without 2 cycle/revolution variability and more than 3 arrays may give superior variability measurement and reduction but at a higher cost.
[0067] FIG. 15 shows nip pressure profiles collected on a roll using the various embedded sensors. The data show clear differences in the profile between the 3 arrays. Most notably, arrays 1 & 3 (separated by 180°) show a significant difference in shape, especially in profile position 14 - 20 .
[0068] While there have been described herein what are considered to be preferred and exemplary embodiments of the present invention, other modifications of the invention shall be apparent to those skilled in the art from the teachings herein and, it is therefore, desired to be secured in the appended claims all such modifications as fall within the true spirit and scope of the invention. Thus, any modification of the shape, configuration and composition of the elements comprising the invention is within the scope of the present invention. Accordingly, what is desired to be secured by Letters Patent of the United States is the invention as defined and differentiated in the following claims. | Multiple groups of sensors are circumferentially spaced apart at each cross-directional position along a sensing roll of a nip press to measure and cancel or nearly cancel the effects of rotational variability which may be acting on the sensing roll. The strategically-placed sensors are designed to measure the pressure being placed against the web that is being advanced through the nip press. The average of the measurements of multiple sensors spaced circumferential apart provides a good cancellation of any rotational variability that might be found at a cross-directional position on the sensing roll. In this manner, a more true measurement of the nip pressure profile can be obtained and better adjustments made to reduce nip pressure profile variability. In addition, the nip variability profile may be used as a predictor of cover or bearing failures, resonant frequencies and other roll anomalies. | 3 |
TITLE OF THE INVENTION
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to an electromagnetic actuator intended to operate devices such as valves or switches and having a plurality of possible states, controlled by the positioning of a rotary element.
Discussion of Background
The displacement detween two consecutive stable positions constitutes a rapid transition achieved by application of a current in at least one pair of coils. The operation of such devices by electric motors usually necessitates the use of locking mechanisms to guarantee positioning at rest in one of the sought positions after a rotary displacement, and to prevent untimely displacements in the absence of control signals. The prior art teaches the technique of actuators provided with a rotor disposed in the air gap of a stator structure formed by a first magnetic circuit provided with four pole shoes, each equipped with an exciting coil. The rotor has a magnetized thin portion comprising two pairs of thin poles magnetized transversely in opposite directions. Such actuators are intended in particular for control of valves or switches. These actuators exhibit the feature of having a broad zone in which the force is constant. As a result, it is possible to construct actuators having very great reproducibility and very great angular precision under automatic control.
To achieve positions that are stable in the absence of current, the prior art actuators are usually provided with a ratchet wheel to lock the position of the actuator after a displacement. The mechanical parts employed for locking are a source of noise and wear. In addition, they lead to higher ts for manufacture and assembly of such actuators.
SUMMARY OF THE INVENTION
The object of the present invention is to construct an actuator provided with at least two stable positions, with a strong locking torque with or without current, not necessitating mechanical locking parts.
To this end the present invention relates to an electromagnetic actuator having four positions that are stable in the absence of current, for operation of a device such as a valve or switch, the actuator being provided with a thin rotationally movable magnet, having two pairs of magnetic poles magnetized transversely in alternate directions, and a stator structure provided with four pole shoes of developed length P, each equipped with an exciting coil, two consecutive poles of the thin magnet being separated by a distance d. The thin magnet is movable in an air gap of dimension E, the dimensional ratios P/E and P/d being larger than 8.
Such an actuator has a locking torque of almost 30% of the motor torque when the diametral plane separating the two magnets is in one of the planes passing between two pole shoes.
Such an actuator can be constructed in two variants: a first variant in which the movable portion has the shape of a disk, and a second variant in which the movable portion has the shape of a tube.
According to the first variant, the movable portion comprises a yoke of circular cross section integral with a thin magnet in the shape of a disk, having two complementary sectors extending for about 180° and magnetized in two opposite axial directions, the pble shoes of the stator portion disposed facing the movable magnet having an annular shape extending for about 90°.
Advantageously, the semi-annular surface of the pole shoes of the stator portion is extended by a foot of smaller cross section, the exciting coil encircling the said foot.
Preferably the shoes are integral with a disk-shaped magnetic-flux closing part.
According to one particular embodiment, the stator structure comprises a first ferromagnetic part having two pole shoes and a second ferromagnetic part having two pole shoes, the two stator parts being disposed on both sides of the thin disk-shaped magnet, the planes passing through the top surface of the pole shoes being spaced apart by a distance d, and the two stator parts being offset by 90°.
According to a second constructional variant, the stator portion is formed by an inner part of cylindrical shape of ferromagnetic material, having two diametrically opposite lateral notches for positioning of an electric coil, and by a peripheral part of tubular shape having two longitudinal inner grooves for positioning of a second electric coil, the median planes of the two coils being perpendicular.
According to a first embodiment, the movable portion comprises a yoke of cylindrical shape and a thin cylinder-shaped magnet having two complementary tile-shaped sectors extending for about 180° and magnetized in two opposite radial directions.
Advantageously, the stator portion is formed by an inner part of cylindrical shape of a ferromagnetic material, having two diametrically opposite lateral notches for positioning of an electric coil, and by a peripheral part of tubular shape having two longitudinal inner grooves for positioning of a second electric coil, the median planes of the two coils being perpendicular.
According to a second embodiment, the stator structure is formed by an inner part of cylindrical shape of a ferromagnetic material, and by a peripheral part of tubular shape having four longitudinal inner grooves for positioning of four electric coils, the median planes of the two coils being angularly offset by 90°.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood in the description hereinafter, provided with reference to the drawings, wherein:
FIG. 1 represents an exploded view of an actuator according to the first variant,
FIG. 2 represents an overhead view of the pole shoes,
FIG. 3 represents the curve of actuator torque versus position,
FIG. 4 represents a median sectional view of the actuator,
FIG. 5 represents an exploded view of a second embodiment,
FIG. 6 represents an exploded view of a third embodiment,
FIG. 7 represents a transversal sectional view of a second constructional variant of the actuator,
FIG. 8 represents a transversal sectional view of another embodiment of the actuator.
FIG. 1 represents an exploded view of an actuator according to the first constructional variant.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The actuator comprises a movable portion (1) and a fixed portion (2).
The movable portion (1) is provided with a thin magnet (3) formed from two pairs of poles (4, 5) magnetized axially in opposite directions, each extending for about 180°. The transitions (6, 7) between two pairs of poles (4, 5) are smaller than 1°. The magnet (3) is constructed by joining two half magnets or preferably by magnetizing two sectors of a thin disk of a material such as ferronickel or any other material used for construction of permanent magnets.
The movable portion (1) is also provided with a yoke (8) of ferromagnetic material. The magnet (3) is attached close to this yoke (8).
The fixed portion comprises four pole shoes (9 to 12) formed by annular sectors extending for almost 90° and attached by feet (14 to 17) to a flux-closing plate (13). Electric coils (18 to 21) encircle the feet (14 to 17) to excite the pole shoes (9 to 12). Two pole shoes are separated by a free space (22 to 25), the length of which, measured along the mean perimeter, is d.
The actuator functions as follows:
In rest position No. 1, the first pair of magnet poles (4) having the SOUTH pole up is aligned with the two shoes (10, 11), the other pair of magnet poles (5) being aligned with the other two shoes (9, 12). The transitions (6, 7) are aligned respectively with the diametrically opposite spaces (25), (23).
This first rest position is stable in the absence of current. It is necessary to apply a significant torque to displace the movable portion.
In what follows, it will be considered that the flow of a positive (or respectively negative) current in one of the coils tends to cause the North (or respectively SOUTH) pole of the magnet to be displaced until the potential of the magnetic poles is added to that of the magnet.
Departure from rest position No. 1 is achieved by energizing the two consecutive coils (20, 21) positively and the two consecutive coils (18, 19) negatively. The movable portion is then displaced by 90°, ultimately occupying a rest position No. 2. This position corresponds to alignment of the first pair of magnet poles (4) having the SOUTH pole up with the two shoes (11, 12), the other pair of magnet poles (5) being aligned with the other two shoes (9, 10). The transitions (6, 7) are aligned respectively with the diametrically opposite spaces (22), (24).
To return from rest position No. 2 to rest position No. 1, it is necessary to energize the two coils (19, 20) positively and to energize the two coils (18, 21) negatively.
If the actuator is intended to cause an element to pivot between two positions offset by 90°, as for a valve control, the two diametrically opposite coils (18, 20) are always energized in the same manner. Pivoting from one of the positions to the other position is achieved by inverting the polarity of energization of the other two diametrically opposite coils (19, 21).
It is also possible, by combined energization specific to the purpose, to displace the movable element (1) into the other rest positions that are offset by 90° relative to the rest positions No. 1 and No. 2.
FIG. 2 represents an overhead view of the pole shoes.
The dimensional characteristics are determined by measurement along the mean perimeter (26). The mean perimeter (26) is the circle whose radius corresponds to the mean between the radius R1 of the inner edge of the shoes (9 to 12) and the radius R2 of the outer edge of the shoes (9 to 12).
In the following,
P designates the width of the pole shoes (9 to 12),
E designates the air gap between the top of the pole shoes (9 to 12) and the bottom surface of the movable yoke (see FIG. 4),
d designates the distance between two consecutive pole shoes (9 to 12).
One of the characteristics necessary to achieve the technical effect constituting the object of the invention, or in other words optimization of the amplitude and stiffness of the currentless locking torque, lies in the choices of dimensional ratios.
A large value, typically greater than 8, will be chosen for the ratio P/E. A value close to P/8 will be chosen for the distance d.
In this case, the actuator exhibits maximum currentless locking torque (typically 30% of the nominal torque with current) over the four stable positions, and maximum stiffness of this currentless torque law (typically 10 mNm/degrees), while retaining a starting torque sufficient for acceleration of the rotor and an end-of-travel stiffness with current on sufficient to brake the rotor. FIG. 3 represents a typical example of the end of torque with or without current as a function of position.
FIG. 4 represents a median sectional view of the actuator through the plane A-A'.
The movable portion (1) is integral with a shaft (27) passing through the stator portion (2). The air gap E separating the bottom surface (28) of the yoke (2) and the top surface (29) of the pole shoes (9 to 12) is determined by means of a thrust ball bearing (30). Positioning of the movable portion (1) and of the stator portion (2) is ensured by the magnetic attraction of the permanent magnets, thus avoiding the use of additional mechanical means to ensure immobilization of the shaft relative to the stator structure (2). In the described example, therefore, the actuator has a single stop acting to limit the axial travel in the direction of the movable portion (1) toward the stator portion (2), but does not have a stop in the opposite direction.
FIG. 5 represents a second embodiment of the actuator in the "disk magnet" configuration.
In this embodiment, the disk magnet (3) is integral not with a yoke but only with a connecting part with a shaft, which is not shown in this figure.
The fixed portion is provided with two stator portions (31, 32) disposed on both sides of the magnet (3). Each of the stator portions (31, 32) is provided with two pole shoes, respectively (34, 35) and (36, 37). Each of the pole shoes (34 to 37) is excited by a coil (38 to 41). The two stator portions (31, 32) are offset angularly in such a manner that their planes of symmetry BB' and CC' form an angle of 90° between them.
In this embodiment, the pole shoes can extend for an angle larger than 90°.
In this way, the distance d between the ends of two consecutive shoes can be reduced to 0 or can even have a negative sign. Preferably, the pole shoes (35 to 37)
extend over the largest possible angular aperture, and allow a minimum space to be present for passage of coils.
FIG. 6 represents another embodiment of an actuator of the disk-magnet type. The two stator portions (31, 32) are symmetrical relative to the plane of the thin magnet (3), and each is provided with four pole shoes (9 to 12). The pole shoes of one of the pole [sic: stator?] portions (32) are excited by electric coils (18 to 21), while the pole shoes of the other stator portion (31) can be optionally excited or non-excited.
FIGS. 7 and 8 represent two embodiments of the actuator variant with the tubular magnet.
FIG. 7 represents an embodiment in which the stator portion is provided with an inner cylindrical part (40) integral with the tubular magnet formed by two pairs of poles (41, 42) in the shape of tiles extending for about 180°, each magnetized radially in opposite directions. It is also possible to provide an inner cylindrical part that is not integral with the tubular magnet.
The outer stator portion (43) comprises a cylindrical part having four grooves (44 to 47), which define between them the four pole shoes (48 to 51). Each of the shoes (48 to 51) is encircled by a coil in the shape of a loop (52 to 55).
For the actuators according to the tubular variant, the dimensions P and d are measured along the internal surface of the pole shoes.
The energization sequences are described hereinbelow with the convention that the rotor is represented in FIG. 7 in -45° position.
______________________________________Position ofrotor at endof travel Coil 2 Coil 3 Coil 4______________________________________ -45° + + - --135° + - - ++135° - - + + +45° - + - +______________________________________
FIG. 8 represents another embodiment of an actuator with tubular structure.
The stator portion is provided with an inner part (56) of cylindrical shape having two diametrically opposite grooves (57, 58). A loop-type coil (59) encircles the inner stator portion (56) and is lodged in the two grooves (57, 58). The two grooves (57, 58) define between them the first two shoes (60, 61). The second stator portion comprises a tubular part (62) also having two grooves (63, 64) offset by 90° relative to the two grooves (58, 59) of the inner part (56). The other two shoes (66, 67) are formed between these two grooves (63, 64). A second electric coil (65) is lodged in these grooves (63, 64). In the described example, these grooves are formed on the inner surface of the tubular part (62).
It is understood that these examples of coil arrangements are described by way of example, and in no way do they constitute an exhaustive list of conceivable options.
The present invention is in no way limited to the foregoing embodiment, but to the contrary covers all variants. | An electromagnetic actuator has four positions which are stable in the absence of a current and moves rapidly between these positions when acted upon by a current. The actuator has a thin, rotatable magnet (3) with two pairs of magnetic poles transversally magnetised in alternate directions, and a stator member having four pole pieces (9-12, 34-37, 48-51) of developed length P, each with an excitation coil. Two consecutive poles of the thin magnet (3) are spaced by a distance d. The thin magnet (3) is movable in an airgap of width E. wherein the size ratio P:E and P:d is greater than 8. The invention is useful for driving a device such as a valve or a switch. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a memory controller and an operating method for the same, especially to a memory controller for using a downgrade memory with initialization step and an operating method for the same
[0003] 2. Description of Prior Art
[0004] FIG. 1 shows a block diagram of a conventional DDR SDRAM, which exemplifies a prevailing DRAM structure since the commencement of SDRAM. The shown memory is divided into a plurality of banks selected by bank address. The memory cells in each bank are accessed through a plurality of column addresses and a plurality of row addresses. As also shown in this figure, the column addresses and the row addresses are generally accessed in multiplexing way as the capacity size of DRAM memory increases. Taking a 256M (32M*8) memory as example, all the address pins A 0 -A 12 in address bus shown on left-top side of FIG. 1 are allocated to row address, while part of the address bus (for example, A 0 -A 9 ) are allocated to column address in multiplexing fashion to save pin count. As also shown in FIG. 1 , the bus of the memory also comprises bank address BA 0 , BA 1 to select memory bank, control signal pins /CAS, /RAS, /WE, and /CS (where slash “/” indicated inverted active signal) and data signal pins DQ 0 -DQ 7 . The address pins A 0 -A 12 and BA 0 , BA 1 can also be used for setting mode registers besides addressing.
[0005] FIG. 2 shows an allocation table for row address, column address and bank address of a standard SDRAM memory. Taking also the 256M (32M*8) memory as example, the address pin setting for row address, column address and bank address is (2, 13, 10). As can be seen from FIG. 2 , the pin counts of the SDRAM memory has specific regulation for correctly accessing the SDRAM memory through a memory controller.
[0006] As the progress of semiconductor technology, the capacity of DRAM memory is also rapidly increased. The current operation system also has capability to access memory larger than 4G bytes and the capacity of the commercially available memory is generally larger than 128 M bytes. Semiconductor memories are generally subjected to a test step after manufacture. If the defect of the memory is not serious after examination by the test step, the error can be corrected by redundant memory cells before package of the memory. However, if the defect of the memory is serious, the error cannot be corrected by redundant memory cells. The defected memory will be dropped or used as downgrade memory. In the downgrade memory, only accessible portion in the memory is used and the storage capacity is generally smaller than the normal capacity.
[0007] The applications of the conventional downgrade memory have following three ways, or the combination thereof.
[0008] As shown in FIG. 3A , in the first conventional way to use downgrade memory, an external redundant memory 76 is used to correct the error of the downgrade memory 70 . An external non-volatile memory unit 72 is used to record the defect location and used for the reference of the external redundant memory 76 . The external non-volatile memory unit 72 can be realized by, for example, EEPROM or Flash memory and the external redundant memory 76 can be realized by, for example, SRAM or DRAM memory. The external redundant memory 76 can be integrated into ASIC or independently arranged. A comparison/control unit 74 compares an accessing address with defect location and the comparison result is used to control a data bus multiplexer 78 to determine whether the output will be generated by the external redundant memory 76 . An alternative way is to use the comparison/control unit 74 to control the DM/DQM signal of memory 70 to control the output from the memory 70 and the external redundant memory 76 . The first conventional way has a disadvantage of higher cost caused by the high speed and complicated comparison/control unit 74 . The comparison/control unit 74 may need to integrate with the external redundant memory 76 to the same ASIC. However, the use of data bus multiplexer 78 to intercept data bus or the use of DM/DQM signal of memory 70 will cause bus contention problem. The accessing speed of the downgrade memory is limited. Moreover, the use of non-volatile memory unit 72 to record the defect location and the complexity in the comparison/control unit 74 will limit the application of the first conventional way to downgrade memory with less defect.
[0009] The second conventional method involves data line division, where the defected areas are precluded in terms of data line DQ. With reference to FIG. 3B , where two 32M*8 SDRAMs are tested and sorted and are used with 32M*1 bit DQ line. For example, if one 32M*8 SDRAM has available area of 32M*2(DQ0−DQ1) and another 32M*8 SDRAM has available area of 32M*6(DQ2−DQ7), the available 2+6=8 DQ lines can be drawn from the two SDRAMs such that a 32M*8 SDRAM is simulated. This method has the advantage of low cost. However, the utilization rate thereof is limited, because the division based on the 32M*1 bit DQ is not compatible with global area layout inside the memory. For example, when all 8 bits for one address are malfunctioned, this defected memory cannot be used as downgrade memory by this method even though this defect is minor.
[0010] The third conventional method uses address line division to preclude the defected area in terms of address line. Taking a 32M*8 DRAM as example (as shown in FIG. 2 , the pin setting is Bank*Row*Column=2*13*10), the defected area for this DRAM is corresponding to the portion with Row address A 12 being High after test. In other word, the defected area will never be accessed if the Row address A 12 is kept pulling High. In this situation, as shown in FIG. 3C , the defected area can be precluded by always pulling low the physical address line A 12 . With reference also to FIG. 2 , the memory downgraded in this way can be used as a standard 16M*8 DRAM. This downgrade method has the advantage of versatile variation because the address line has large amount. The variation can also be applied to pull High/Low, address inversion etc. The downgrade method can be performed for one fold downgrade or two fold downgrade (32M*8 down to 8M*8) or more folds. However, the downgrade method has the disadvantage of involving ASIC for address conversion. If the address line to be processed is not an exclusive address line, namely, the address line is multiplexed for row address and column address; ASIC is needed for address conversion. Moreover, the downgraded memory may not be a standard DRAM after address line division. For example, a 16M*8 DRAM (Bank*Row*Column=2*12*10) is downgraded by pulling low the A 11 address line, however, this downgraded memory is not a standard DRAM as can be reference to FIG. 2 . Therefore, an ASIC is needed to convert the signal of the downgraded memory to simulate an 8M*8 DRAM with pin assignment Bank*Row*Column=2*12*9. Moreover, for advanced DRAM memory such as SDRAM and its successors, the address lines there are also used for initialization commands such as MRS, EMRS commands. Therefore, additional ASIC is needed for signal conversion, which can be referred to Taiwan Patent No. 198183. This patent is also filed by the same applicant as the present invention.
[0011] However, the above-mentioned related art has the disadvantages of high cost and signal delay to hinder high-speed application. Moreover, various ASICs are needed for different address conversion schemes, this is inflexible. Moreover, the above-mentioned related art downgrade method is limited to certain conversion, for example, column address reduction instead of column address augmentation.
SUMMARY OF THE INVENTION
[0012] It is the object of the present invention to provide a memory controller for downgrade memory to overcome above-mentioned problem. The utilization rate can be increased and with extremely low delay and low cost.
[0013] According to a preferred embodiment of the present invention, the memory controller is provided between a downgrade memory and a memory requester. Herein several items are defined to better understand the following. The term “non-defect area” is referred to a cell group without any defect. The term “defect area”, is referred to a cell group which at least covers all defect cells. The memory controller sends initialization signals to the downgrade memory according to pin setting of the downgrade memory. The memory controller helps the memory requester to access at least a subset of the non-defect area of the downgrade memory according to memory space requested by the memory requester.
[0014] Preferably, the memory controller according to a preferred embodiment of the present invention sends predetermined signals to downgrade logical addresses of the downgrade memory according to a downgrade type setting. The predetermined signals can be directly pulling high/low according to the downgrade type setting or some specific signals or the logic combination thereof.
[0015] Preferably, the memory controller according to a preferred embodiment of the present invention comprises a recording unit to record the information of available logical address, correct initialization command and downgraded status. The recording unit can be implemented by jumper, connection status of resistor or EEPROM.
[0016] The memory controller according to the present invention can be easily applied to most current commercially available memory. The downgrade addresses can be bank addresses, row address and column addresses precluded with burst length range. The memory controller according to the present invention can be easily applied to full page burst memory (for example, frame buffer memory) as long as the page size of the downgrade memory is larger than the requested page size.
BRIEF DESCRIPTION OF DRAWING
[0017] The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
[0018] FIG. 1 shows a block diagram of a conventional DDR SDRAM.
[0019] FIG. 2 shows an allocation table for row address, column address and bank address of a standard SDRAM memory.
[0020] FIG. 3A shows the first conventional way to use downgrade memory.
[0021] FIG. 3B shows the second conventional way to use downgrade memory.
[0022] FIG. 3C shows the third conventional way to use downgrade memory.
[0023] FIG. 4A shows a schematic diagram of a first preferred embodiment of the present invention.
[0024] FIG. 4B shows a schematic diagram of a second preferred embodiment of the present invention.
[0025] FIG. 4C shows a schematic diagram of a third preferred embodiment of the present invention.
[0026] FIG. 4D shows a schematic diagram of a fourth preferred embodiment of the present invention.
[0027] FIG. 4E shows a schematic diagram of a fifth preferred embodiment of the present invention.
[0028] FIG. 5 demonstrates the working principle of the first preferred embodiment of the present invention.
[0029] FIG. 6 shows a flowchart according to a preferred embodiment of the present invention.
[0030] FIG. 7A shows a mapping relationship with reference to the control input pins.
[0031] FIG. 7B shows another mapping relationship with reference to the control input pins.
[0032] FIG. 8 is a schematic diagram showing the concept of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0033] In any application system using memory, a memory controller is employed to facilitate one or more sub-system to access the memory. The sub-system is referred to as Memory Requester hereinafter for clarity. The portion of the memory controller, which faces the memory, is referred to as Front-End. The portion of the memory controller, which faces the memory requester, is referred to as Back-End hereinafter for clarity. The memory controller has versatile functions such as memory refresh, switch and trace of memory page, initialization control of memory and mapping relationship between front-end and back-end.
[0034] In the prior art downgrade memory, one or more downgrade memory is used to simulate a standard memory for the accessing of memory controller. In the present invention, the memory controller has a built-in initialization control and provides mapping relationship between front-end and back-end for downgrade memory.
[0035] FIG. 4A shows a schematic diagram of a first preferred embodiment of the present invention. The present invention can be applied to any electronic system 10 needing to access memory. As shown in this figure, the electronic system 10 comprises one or more sub-systems 100 and the sub-systems 100 accesses a downgrade memory 20 through the help of a memory controller 120 .
[0036] FIG. 5 demonstrates the working principle of the first preferred embodiment of the present invention, where the sub-systems 100 needs memory with 2 m addressable space, namely, m logical address lines. A memory 20 with 2 n addressable space (namely the memory 20 has n logical addresses including bank address, row address and column address), the available capacity after address line division needs to exceed 2 m bits.
[0037] In this example, q logical addresses (q≧0) in the Y physical lines are the logical address for downgrade division (hereinafter, the q logical addresses are referred to as first downgrade logical addresses) and the downgrade command and initialization commands for those q logical address do not need logic gate, namely, the physical address lines corresponding to the q logical address can be directly connected to ground level or high level. Moreover, the X physical lines for the remaining (n−q)=p logical address lines are linked to the memory controller 120 , where the p logical addresses are referred to as linked logical addresses. In the p logical addresses, there are r logical addresses (r>0) and (p−r)≧m, where the r logical addresses are referred to as second downgrade logical addresses. When the memory controller 120 sends initialization commands for the memory 20 , the memory controller 120 sends correct signal satisfied with standard through the X physical lines according to initialization needs and a pin setting of the downgrade memory. In memory accessing stage, the memory controller 120 helps to access m requested logical addresses, while the memory controller 120 sends suitable signal for the r second downgrade logical addresses according to the downgrade type setting. For the (p−r−m) unused logical addresses, the memory controller 120 sends predetermined signal for those logical addresses. The (p−r−m) unused logical addresses can also be treated as downgrade logical addresses for simplification.
[0038] The downgrade type setting imposes limitation on applicable signals for certain logical addresses to prevent from using the defect area in the downgrade memory. When the first and the second downgrade logical addresses of the downgrade memory are applied with signals complied with the downgrade type setting in data-accessing stage, the defect area can be prevented from accessing. In above-mentioned preferred embodiment, the first downgrade logical addresses (the q logical addresses) are not processed through the memory controller 120 . The second downgrade logical addresses (the r logical addresses) are processed through the memory controller 120 . The memory cells corresponding to the (p−r−m) unused logical addresses are beyond the requirement of the memory requester. Therefore, the (p−r−m) unused logical addresses can be treated as the second downgrade logical addresses for simplification.
[0039] FIG. 6 shows a flowchart according to a preferred embodiment of the present invention.
[0040] Step S 600 : Determining the logical addresses number m required by the electronic system and the linked logical addresses p.
[0041] Step S 610 : Determining the second downgrade logical addresses r among the p linked logical addresses.
[0042] Step S 620 : Sending initialization signal through the X linked physical lines.
[0043] Step S 630 : Accessing 2 m addressable space in the memory according to the logical addresses number m required by the sub-system.
[0044] Step S 640 : Sending suitable signal to the r second downgrade logical addresses.
[0045] Step S 650 : Sending predetermined signal, such as signals of fixed level, to the (p−r−m) unused logical addresses.
[0046] FIG. 4B shows the block diagram according to another preferred embodiment of the present invention, where the sub system 100 is exemplified with a micro controller 100 . A recording unit 140 is incorporated to help the memory controller 120 to send correct initialization command and signal conversion according to downgrade type setting of the memory 20 .
[0047] The recording unit 140 can be any medium with recording function such as jumper, connection status of resistors, EEPROM, record or firmware in micro-controller. The recording unit 140 can be used to indicated the supportable types of downgrade memory for the memory controller 120 . For example, the supportable types of downgrade memory can be 4M*16 or 8M*16 memory.
[0048] In the second preferred embodiment of the present invention, there is only one memory requester 100 in back-end of the memory controller 120 and the required memory capacity is 8M*16. The memory controller 120 is connected to the memory requester 100 through address lines SA 0 , SA 1 . . . SA 22 . The memory 20 connected to the front end of the memory controller 120 is an 8M*16 downgrade memory, which is downgraded from a 16M*16 SDRAM. The memory 20 has following six address division ways, where we use BA for representing bank address, RA for representing row address and CA for representing column address. The first division way is CA 7 =L to indicate a required portion in the non-defect area; the second division way is CA 7 =H to indicate a required portion in the non-defect area; the third way is RA 7 =L to indicate a required portion in the non-defect area; the fourth way is RA 7 =H to indicate a required portion in the non-defect area; the fifth way is CA 7 =RA 7 to indicate a required portion in the non-defect area and the sixth way is CA 7 =/RA 7 to indicate a required portion in the non-defect area, where slash “/” means inverted phase. The physical address lines A 0 . . . A 12 ,BA 0 ,BA 1 of the memory 20 are connected to the pins MA 0 . . . MA 14 of the memory controller 120 . In this preferred embodiment, the recording unit 140 is realized by connecting three jumpers JP 0 -JP 2 to three control input pins S 2 , S 1 and S 0 of the memory controller 120 . The skilled in the art would know that the no prior art technology can simulate the downgrade memory with above-mentioned six address division ways into standard 8M*16, even though the downgrade memory with above-mentioned six address division ways has the memory capacity of 8M*16.
[0049] The memory controller 120 has following operations according to the present invention. Provided the memory controller 120 sets the CAS Latency=3, Wrap Type being linear Mode, Burst Length=4, then the memory controller 120 sends 0,0,0,0,0,0,0,0,0,1,1,0,0,1,0 for pins MA 14 . . . MA 0 in MRS command during initialization stage of the memory. Namely, the signals sent to MA 1 ,MA 4 ,MA 5 pins are high, and the remaining signals are low, this step can also be referred to the description of S 620 .
[0050] In data accessing stage, the memory controller 120 establishes a mapping relationship between the logical address BA 0 ,BA 1 ,RA 0 . . . RA 12 ,CA 0 . . . CA 8 at front end and the address lines SA 0 ,SA 1 . . . SA 22 at back end according to the input status of the control input pins S 2 , S 1 , S 0 and with reference to the relationship in FIG. 7A . As can be seen from this figure, the memory controller 120 establishes a mapping relationship for supporting downgrade memory characterized by CA 7 =L when the S 2 ,S 1 ,S 0 are L,L,L. the memory controller 120 establishes a mapping relationship for supporting downgrade memory characterized by CA 7 =H when the S 2 ,S 1 ,S 0 are L,L,H. The operation for above mapping relationship can also be referred to the description for step S 630 .
[0051] FIG. 4C shows the third preferred embodiment of the present invention, where an additional pin S 3 is added to the recording unit 140 for supporting other address division types. When the signal at pin S 3 is low, the memory controller 120 can support above-mentioned six address division types. When the signal at pin S 3 is high, the memory controller 120 can also support six new address division types. As shown in FIG. 7B , when S 3 , S 2 , S 1 , S 0 are H,L,L,L, the CA 5 =L address division type can be supported. When S 3 , S 2 , S 1 , S 0 are H,L,L,H, the CAS=H address division type can be supported. When S 3 , S 2 , S 1 , S 0 are H,L,H,L, the RA 5 =L address division type can be supported. When S 3 , S 2 , S 1 , S 0 are H,L,H,H, the RA 5 =H address division type can be supported. When S 3 , S 2 , S 1 , S 0 are H,H,L,L, the CA 5 =RA 5 address division type can be supported. When S 3 , S 2 , S 1 , S 0 are H,H,L,H, the CA 5 =/RA 5 address division type can be supported.
[0052] As can be seen from above description, the memory controller 120 according to the present invention can support memory of almost any address division type as long as sufficient column address amount is reserved for page size and the column address for burst length is precluded according to the requirement of the requester. Moreover, the prior art downgrade method by address division needs different circuits for different division ways, while the memory controller 120 according to the present invention needs only change mapping relationship of address lines according to the setting of recording unit 140 . Therefore, the design complexity is greatly reduced.
[0053] As can be seen from the second and the third preferred embodiment, the present invention can be applied to various address division schemes. For those applications with high efficiency and high speed request, the following fourth and the fifth embodiments shows simplifying scheme for increasing the utilization rate of downgrade memory without increasing internal delay.
[0054] FIG. 4D shows the fourth embodiment of the present invention. The memory controller 120 has similar back end as that in the second preferred embodiment However, for the connection between the memory 20 and the memory controller 120 , the A 6 pin can be selectively connected to MA 7 pin and the A 7 pin can be selectively connected to the MA 6 pin through the connection of external resistor or jumper. Therefore, the address division ways can be expanded to CA 6 =L, CA 6 =H, RA 6 =L, RA 6 =H, CA 6 =RA 6 and CA 6 =/RA 6 without increasing complexity of memory controller 120 .
[0055] FIG. 4E shows the fifth embodiment of the present invention. The fifth embodiment also supports similar downgrade memory with the third embodiment but in different way. In comparison with the third embodiment, the fifth embodiment is added with an identification input pin S 3 and the A 5 and A 7 pins of the memory 20 are connected to the memory controller 120 through the connection of external resistor or jumper. For MRS signal of initialization, when the pins A 5 and A 7 are connected to the pins MA 5 and MA 7 , the S 3 pin is set to be low such that the signals for the pins MA 14 . . . MA 0 are the same as the third embodiment to ensure the memory 20 has received the correct MRS commands. When the signals of the pins A 5 and A 7 are switched, the signal at the S 3 pin is set to be high such that the signals for the pins MA 14 . . . MA 0 are 0,0,0,0,0,0,0,1,0,0,1,0,0,1,0. Therefore, the memory 20 has received the correct MRS commands. The mapping relationship for the front end and back end of the memory controller 120 is independent of the signal at the S 3 pin and is the same as that shown in FIG. 7A . Therefore the circuit complexity is transferred to the output logic circuits for initialization. Those output logic circuits for initialization can be set with arbitrary wait state and the overall system accessing is not influenced.
[0056] The fifth embodiment of the present invention can be further simplified for system with micro controller. The initialization control can be performed by firmware of the micro controller. Therefore, the input state of the S 3 pin can be read by the micro controller and the various MRS signals are provided by firmware to not increase hardware complexity.
[0057] The above-mentioned embodiments are exemplified with the mapping relationship between logic address signals of front end and back end in the memory controller 120 . However the mapping relationship between logic address signals of front end and back end is just a subset of a generic mapping relationship between front end and back end of the memory controller 120 . The concept of the present invention can be easily applied to downgrade memory with non-2′ power capacity.
[0058] The sixth embodiment of the present invention can be used for a downgrade memory with non-2′ power capacity. Provided that there are three memory requesters and each of the memory requesters needs an individual 1M*16 memory capability, the total memory capability needed is 3M*16. In this preferred embodiment, the memory controller 120 comprises two control input pins S 1 and S 0 to identify and support for 3M*16 downgrade memory, which is downgraded from 8M*16 memory. The memory controller 120 according to the sixth embodiment of the present invention can support following downgrade type. When the signals of the pins S 1 ,S 0 are L,L, the memory controller 120 can support a 3M*16 downgrade memory having a required portion in the non-defect area with the pin setting CA 8 =H AND NOT(RA 8 =L AND CA 7 =L). When the signals of the pins S 1 ,S 0 are L,H, the memory controller 120 can support a 3M*16 downgrade memory having a required portion in the non-defect area with the pin setting CA 8 =H AND NOT(RA 8 =L AND CA 7 =H). When the signals of the pins S 1 ,S 0 are H, L the memory controller 120 can support a 3M*16 downgrade memory having a required portion in the non-defect area with the pin setting CA 8 =H AND NOT(RA 8 =H AND CA 7 =H). Hereinafter the three memory requesters are referred to as RQ 0 , RQ 1 , and RQ 2 . The respective 1M*16 for the memory requesters RQ 0 , RQ 1 , and RQ 2 form a virtual space of 3M*16. If the three highest addresses in the memory site are selected as CA 8 , RA 8 , and CA 7 , the memory space is divided into eight 1M*16 addressable sub-spaces by the logical addresses CA 8 , RA 8 , and CA 7 . The memory needed by the memory requesters RQ 0 , RQ 1 , and RQ 2 belong to three memory sub-spaces in the memory space addressable by the logical addresses CA 8 , RA 8 , and CA 7 . Therefore, the memory controller 120 can serve memory request for the memory requesters RQ 0 , RQ 1 , and RQ 2 as long as the memory controller 120 can establish mapping relationship between three 1M*16 memory locations at memory requester end with three 1M*16 memory sub-spaces at front end of the memory.
[0059] In the sixth embodiment of the present invention, the memory controller 120 can one by one map the logical addresses SA 19 ,SA 18 . . . SA 0 of the 1M*16 memory location to the logical addresses BA 1 ,BA 0 ,RA 11 . . . RA 9 ,RA 7 ,RA 6 . . . RA 0 , CA 6 ,CA 5 . . . CA 0 of the front end of the memory. When the signals at pins S 1 ,S 0 are L,L and the memory requester RQ 0 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,H,H; when memory requester RQ 1 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,L,H; when memory requester RQ 2 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,H,L. When the signals at pins S 1 ,S 0 are L,H and the memory requester RQ 0 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,L,L; when memory requester RQ 1 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,H,H; when memory requester RQ 2 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,H,L. When the signals at pins S 1 ,S 0 are H,L and the memory requester RQ 0 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,L,L; when memory requester RQ 1 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,L,H; when memory requester RQ 2 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,H,H. When the signals at pins S 1 ,S 0 are H,H and the memory requester RQ 0 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,L,L; when memory requester RQ 1 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,L,H; when memory requester RQ 2 demands for memory accessing, the signals at the logical addresses CA 8 ,RA 8 ,CA 7 are set to be H,H,L.
[0060] FIG. 8 is a schematic diagram showing the concept of the present invention. The downgrade memory is connected to the memory controller 120 through X physical lines and the X physical lines provide p linked logical addresses, which are larger than m logical addresses requested by system. Therefore, the X physical lines exceed what the system requires and the X physical lines provide memory accessing for downgrade memory of different defect types. By setting the memory controller 120 to access partial physical lines among the X physical lines, the memory controller 120 has flexibility to access different portions in the non-defect area in the downgrade memory of different defect types. On the contrary, the conventional memory controller for downgrade memory is generally connected to the downgrade memory with physical lines having number exactly meeting system requirement. Therefore, the conventional memory controller for downgrade memory can only be used for limited types of downgrade memory. The memory controller 120 according to the present invention has ability to connect to more physical lines and can access downgrade memory of versatile defect types through the help of the recording unit 140 . The memory controller 120 according to the present invention can be used for accessing downgrade memory of versatile defect type to reduce cost.
[0061] Moreover, to demonstrate the versatile usage of the memory controller 120 according to the present invention, the application of m requested logical addresses are used to address 2 m memory units. The actual need might not be 2 m memory units and depends on designer choice. The manually assigned memory space for the back end of the memory controller can be generally expressed by a virtual space. When there is only one micro controller, the virtual space is the memory space for the micro controller. When there are different memory requesters at the back end of the memory controller, the memory space required by respective memory requester may be or may not be overlapped and can be manually assigned. The virtual addresses in the virtual space can be indicated by VA( 0 ), VA( 1 ) . . . VA(m− 1 ) and can be linked to the m logical addresses one by one through the memory controller 120 . For example, if the memory controller 120 according to the present invention is applied to DTV, the virtual addresses in the virtual space are the virtual addresses for the micro processor and the DS P processor, respectively. The memory resource requested by the micro processor and the DS P processor can be provided by accessing a downgrade memory through the memory controller 120 according to the present invention. When the memory resource requested is a non-2's power memory unit, a mapping relationship is established between the virtual space and the addressable memory locations in the memory. Therefore, the usage of memory controller 120 according to the present invention is not limited to what can be achieved by address line division, and can be extended addressable space mapping between back end and front end. The above mentioned 2's power memory unit is also a subset for the addressable space mapping.
[0062] Accordingly the memory controller 120 according to the present invention has following advantages:
[0063] 1. Low cost: The current electronic system has a trend of highly integration such that the memory controllers are almost integrated into other chip. Taking PC as an example, the memory controller for main memory is integrated into North Bridge. In VGA card with AGP interface, the memory controller is integrated into single chip with GPU and AGP controller. The slight elaboration on the memory controller will not increase the cost for chip. However, the overall cost can be reduced because the memory controller 120 according to the present invention has flexibility to access other kinds of downgrade memories.
[0064] 2. Applicability for high speed environment: The memory controller according to the present invention involves small gate delay between the memory requester and the memory, while the prior art memory controller involves external 10 delay for ASIC.
[0065] 3. Great utilization rate for memory: The downgraded memory used by the memory controller according to the present invention
[0066] Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims. | A controller apparatus for utilizing downgrade memory and method for operating the same are proposed. The controller apparatus uses address assignment to access the downgrade memory, which is classified by accessible address after testing. The controller apparatus is applicable to various applications, including memory interface controller for the accessing of a sub system. The controller apparatus can be integrated into the sub system within single chip. The controller apparatus further comprises at least one recording unit to record the initialization format and address mapping relation of a specific downgrade memory. Therefore, controller apparatus can be adapted to access various kinds of downgrade memory designated by the recording unit. | 6 |
BACKGROUND OF THE INVENTION
[0001] The invention is directed to a door or lid which is normally hinged to a washer opening to define a top-loading or a front-loading washer. Conventionally such doors or lids have been made of metal with or without a glass panel through which the interior of the washer can be viewed.
DESCRIPTION OF THE RELATED ART
[0002] U.S. Pat. No. 4,695,420 granted on Sep. 22, 1987 and assigned to Caterpillar, Inc. makes reference to the desirability of injection molding plastic articles having a variety of complex shapes and sizes including panels and doors of vehicles or equipment enclosures, such as cab doors. Such cab doors were originally manufactured by utilizing a flat rigid frame fabricated from metal to which is unitized a window in what is termed a costly and time-consuming operation. The window or glazing is floated in a soft gasket channel isolated from the frame to reduce shock-loads and thermal stresses induced by varying coefficients of thermal expansion between the metal frame and the glazing/glass panel. It is believed that the process just described is workable because the window panes in all cases are sheets of transparent plastic material, such as polycarbonate and acrylic with the preferred material being a polycarbonate having a silicone hard coat applied thereto to make the polycarbonate glazing or window pane more scratch-resistant. The silicone hard coat on the peripheral edge is removed by sanding or grinding to assure good bonding between the eventually molded frame and the polycarbonate glazing.
[0003] With the advent of excellent molding qualities of modern plastic materials, an effort was made to form a door by first manufacturing a pre-shaped pane of transparent glass and subsequently integrally molding the latter into a door frame as the window thereof. Following this process, the window pane was distorted and wavy and the door frame had a tendency to warp. However, by utilizing a high modulus plastic material, such as polyurethane and a shrink-reducing filler material, undesired high temperature rise from exothermic reaction was moderated, particularly when a catalyst was added in sufficient amounts to control the weight of the reaction and the heat evolution. Also, by heating the glass and forming the frame by reaction injection molding, both the frame and the glass window pane thermally contract similarly absent window pane buckle and with bonding of the edges of the glass window pane to the frame.
[0004] Glass and specifically tempered glass have heretofore never been provided with an injection molded polymeric/copolymeric frame to form a door or lid, and particularly a washer lid. However, injection-molding polymeric/copolymeric material as an encapsulation or border to form a shelf is well known, as is evidenced by U.S. Pat. No. 5,273,354 granted on Dec. 28, 1993; U.S. Pat. No. 5,362,145 granted on Nov. 8, 1994; U.S. Pat. No. 5,403,084 granted on Apr. 4, 1995; U.S. Pat. No. 5,429,433 granted on Jul. 4, 1995; U.S. Pat. No. 5,441,338 granted on Aug. 15, 1995; U.S. Pat. No. 5,454,638 granted on Oct. 3, 1995; U.S. Pat. No. 5,540,493 granted on Jul. 30, 1996 and U.S. Pat. No. 5,735,589 granted on Apr. 7, 1998.
[0005] Other patents dealing with glass to which material is injection molded normally include windshields to which a gasket is molded and/or cured in situ so as to encapsulate a marginal peripheral edge of the windshield. Typical of such window assemblies and methods of forming the same are found in such patents as U.S. Pat. No. 4,778,366 granted on Oct. 18, 1998; U.S. Pat. No. 4,688,752 granted on Aug. 25, 1987 and U.S. Pat. No. 4,732,553 granted on Mar. 22, 1988.
[0006] Other patents which were located during the search of the instant invention include U.S. Pat. No. 4,543,283 granted on Sep. 22, 1987; U.S. Pat. No. 3,843,982 granted on Oct. 29, 1974; U.S. Pat. No. 6,146,574, granted on Nov. 14, 2000 and U.S. Pat. No. 4,336,301 granted on Jun. 22, 1982.
SUMMARY OF THE INVENTION
[0007] The present invention is specifically directed to a door or lid for a washer, but contrary to the door of U.S. Pat. No. 4,695,420, the transparent panel is constructed from tempered glass and an open frame-like encapsulation is preferably a polymeric/copolymeric synthetic plastic material in the form of acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. The latter specifics of the blended material which is injection molded to form the open frame-like encapsulation achieves a much lower shrink ratio and elasticity, as compared to polypropylene which is normally used in the injection molding of a tempered glass substrate to form a shelf (not a door). Since tempered glass or a similar glass substrate has virtually a zero coefficient of expansion, the same obviously will not expand or contract in relationship to the expansion or contraction of conventional polymeric/copolymeric material, such as polypropylene. Consequently, typical “weld lines” created in the injection molded open frame-like encapsulation or border tend to fracture, particularly as such parts experience temperatures varying between −30° F. to +104° F. However, through the utilization of the specific blended materials latter defined at the ratios stated, such fracture has been essentially eliminated and the washer door or lid of the present invention achieves unexpected longevity, absent deterioration, and aesthetic characteristics at competitive prices, particularly at higher price-ranged washers.
[0008] The aesthetics of the washer lid are also enhanced by designing the exterior of the frame-like encapsulation which is exposed to the consumer as a relatively smooth, unbroken surface except as might otherwise be desired by a washer manufacturer who might specify a recess in the outer surface for reception of a decal, label or the like carrying trademark or other information. The interior of the washer lid which is less susceptible to scrutiny because of it being opened essentially only when the washer is being loaded or unloaded is engineered to include structural characteristics necessary for optimum functionality of the washer lid including, for example, an internally stepped relatively thick inner periphery of the frame-like encapsulation which securely grips and reinforces the peripheral edge of the tempered glass panel, an outboard depending peripheral skirt achieving exterior peripheral rigidity of the frame-like encapsulation, an indiscrete handle portion along an underside of a front wall of the encapsulation which is essentially unobservable when the washer lid is closed, a reinforced corner for a switch actuator, and opposite rear corners rigidly supporting hinges which are utilized to hinge the washer lid to an associated washer opening for movement between open and closed positions thereof.
[0009] With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a fragmentary top perspective view, and illustrates a washer with a washer lid or door of the present invention hinged thereto in its closed position.
[0011] [0011]FIG. 2 is a fragmentary perspective view of the washer of FIG. 1, and illustrates the washer lid in its open position.
[0012] [0012]FIG. 3 is a bottom plan view of the washer lid or door, and illustrates a tempered glass panel bonded by an open frame-like encapsulation formed of one-piece injection molded polymeric/copolymeric plastic material.
[0013] [0013]FIG. 4 is a fragmentary cross sectional view through a corner portion of two identical rear corners of the washer lid, and illustrates a generally L-shaped hinge defined by a mounting portion and a pintle portion with the former being fastened to a depending peripheral skirt of the frame-like encapsulation and the pintle portion passing through a slot of the depending peripheral skirt.
[0014] [0014]FIG. 5 is an exterior fragmentary side elevational view of the hinge of FIG. 4, and illustrates the details thereof.
[0015] [0015]FIG. 6 is an interior fragmentary side elevational view of the hinge of FIG. 4.
[0016] [0016]FIG. 7 is a fragmentary bottom plan view of a forward corner of the frame-like encapsulation, and illustrates a switch actuator seated upon reinforcing ribs projecting from a top panel of the frame-like encapsulation and being secured to the peripheral skirt by fasteners.
[0017] [0017]FIG. 8 is an outside fragmentary side elevational view of the forward corner illustrated in FIG. 7, and illustrates details of the switch actuator.
[0018] [0018]FIG. 9 is a fragmentary cross sectional view of the peripheral skirt of the corner of FIG. 7, and illustrates further details of the switch actuator.
DETAILED DESCRIPTION OF THE INVENTION
[0019] A washer 10 is illustrated in FIGS. 1 and 2 of the drawings and includes a conventional washer body 11 having an interior tub or chamber 12 including an upper frame 13 to which is hinged a novel washer lid or door 20 of the present invention. The upper frame 13 defines an upstanding inner peripheral wall 14 (FIGS. 2 and 4) at opposite rear corners (unnumbered) which the upper frame 13 is provided with openings 15 (FIG. 4) for hinging the washer lid 20 thereto in a manner to be described more fully hereinafter.
[0020] A conventional agitator (not shown) is mounted in the tub or chamber 12 and reciprocates arcuately in a conventional fashion. A conventional safety switch or “ON”/“OFF” switch 18 (FIG. 2) is carried by and beneath an apertured horizontal frame portion 16 of the upper frame 13 of the washer 10 , and is switched “on” and “off” by the washer lid 20 in a manner to be described more fully hereinafter.
[0021] The washer lid or door 20 includes a tempered glass panel 21 of a predetermined peripheral configuration defined by a substantially continuous peripheral edge 22 . The glass panel 21 further includes opposite inner and outer surfaces 23 , 24 , respectively, bridged by the peripheral edge 22 . A peripheral portion 25 of the glass panel 21 is defined by the peripheral edge 22 and immediately adjacent surface portions of the opposite inner and outer surfaces 23 , 24 , respectively.
[0022] An open frame-like encapsulation or border 30 is formed as a one-piece of injection molded polymeric/copolymeric synthetic plastic material. The polymeric/copolymeric synthetic plastic material is preferably acrylonitrile-styrene-acrylate polymer blended with mica glass beads at a ratio of substantially 70%-90% of the polymer and substantially 30%-10% of the mica glass beads, respectively, by weight. The preferable range by weight of the blend is substantially 80% of the polymer to substantially 20% of the mica glass beads. The latter ranges of the polymer and the mica glass beads achieve an extremely low shrink ratio and elasticity, as compared to polypropylene. As the injection molded blended polymer of the open frame-like encapsulation 30 cools, its virtually minimal shrink ratio parallels the almost zero coefficient of expansion of the tempered glass panel 21 . Consequently, weld lines of the injection molded frame-like encapsulation 30 will not fracture, particularly when subject to temperature anywhere between −30° F. to 140° F.
[0023] The open frame-like encapsulation 30 includes an outer peripheral portion 31 and an inner peripheral portion 32 with the inner peripheral portion 32 entirely encapsulating the glass panel outer peripheral portion 25 including the peripheral edge 22 and immediately adjacent surface portions of the opposite inner and outer surfaces 23 , 24 , respectively. The frame-like encapsulation 30 further includes an inner or lower surface 34 and an outer or upper surface 35 defining therebetween the overall inner and outer surface configurations of the frame-like encapsulation 30 and the wall thickness thereof. The frame-like encapsulation inner surface 35 is stepped (FIG. 2) at the frame-like inner peripheral portion 32 and defines thereat a relatively thicker wall thickness than the wall thickness at the outer peripheral portion 31 . However, the outer surface 34 has a configuration which is substantially continuous and unstepped which presents an aesthetic appearance to the washer lid 20 when in the closed position (FIG. 1), and all remaining injection-molded characteristics are formed along the inner surface 35 and are hidden from view (FIG. 1) except, of course, when the washer lid 20 is opened (FIG. 2).
[0024] The outer peripheral portion 31 of the washer lid 20 is defined as continuously downward depending peripheral wall or skirt which is smooth and unbroken except along a front edge (unnumbered) of the frame-like encapsulation 30 . At the front edge (FIGS. 1 - 3 ) of the frame-like encapsulation 30 a curved wall portion 38 (FIGS. 2 and 3) of the depending skirt 31 is recessed inwardly and opens concavely outwardly to define a handgrip recess 40 in association with an overlying ledge or lip 39 of the frame-like encapsulation 30 . In order to open the washer lid 20 , a person merely inserts one or more fingers within the handgrip area 40 (FIG. 1) and lifts upwardly against the ledge 39 to pivot the washer lid 20 from the position shown in FIG. 1 to the position shown in FIG. 2.
[0025] The frame-like encapsulation 30 also includes substantially identical corner portions 50 , 50 (FIGS. 1 and 4) defined by the peripheral skirt 31 with a radius (unnumbered) of each corner portion 50 including an elongated curved slot or opening 52 (FIGS. 4 and 5). Two bosses 53 , 54 project inwardly of the peripheral skirt 31 and each includes a respective bore 55 , 56 . Hinge means in the form of a hinge pin 60 is associated with each corner portion 50 and is of a generally L-shaped configuration defined by a pintle portion 61 connected by a radius portion 62 to a mounting portion 63 which includes respective flattened recessed portions 64 , 65 seated upon and receiving therein the bosses 53 , 54 , respectively. Threaded fasteners 64 ′, 65 ′ are fed through bores (unnumbered) of the bosses 53 , 54 and are threaded into threaded openings (unnumbered) of the flattened portions 64 , 65 , respectively, of the mounting portion 63 of each hinge 60 thereby rigidly attaching each of the hinges 60 to the peripheral skirt 31 adjacent an associated one of the rear corner portions 50 . The pintle portions 61 of the hinge pins 60 lie in coaxial relationship to each other and project in opposite directions. Each pintle portion 61 is fitted in one of the openings 15 (FIG. 4) of the inner peripheral wall 14 of the upper frame 13 of the washer body 11 to thereby permit pivoting movement of the washer lid 20 between the positions shown in FIGS. 1 and 2 of the drawings.
[0026] At the corner portion 50 adjacent the hand recess 40 (FIGS. 3, 7, 8 and 9 ), a one-piece molded switch-actuator mechanism 69 defined by a mounting block 70 having a switch actuator leg 71 rests upon four substantially parallel relatively spaced reinforcing ribs 72 which project downwardly from the inner surface 34 of the frame-like encapsulation 30 . The peripheral skirt 31 in the area of the ribs 72 includes two bores 74 through which pass fasteners 75 which are threaded into the mounting block 70 to rigidly secure the same in the manner illustrated in FIGS. 7 through 9 of the drawings. The leg 71 of the switch-actuating mechanism 69 is aligned with the safety “ON”/“OFF” switch 18 to close the latter when the washer lid 20 is closed (FIG. 1) and open the latter when the washer lid 20 is open (FIG. 2) to respectively start and stop the washer agitator (not shown) in a conventional manner.
[0027] A substantially inwardly directed flange 85 is located at each of the front corners 50 , 50 of the washer lid 20 in spaced relationship to the inner surface 34 (FIGS. 3, 7 and 9 ). The flange 85 illustrated at the upper left hand corner 50 of FIG. 3 includes an opening 86 carrying a rubber or similar flexible stop (not shown) which contacts and rests upon the horizontal frame portion 16 of the upper frame 13 of the washer body 11 when the washer lid 20 is in the closed position thereof (FIG. 1). The leg 71 of the switch-actuating mechanism 69 passes through and is radially supported by the opening 86 of the flange 85 (FIGS. 7 and 9).
[0028] As is most readily apparent from FIG. 1 of the drawings, the washer lid 20 presents an extremely aesthetic appearance to the overall washer 10 due to the relatively smooth and unbroken upper/outer surface 35 of the encapsulation 30 . Even in the open position (FIG. 2) of the washer lid 20 , the interior of the washer lid 20 is relatively aesthetic in appearance since the hinges 60 , 60 are unobtrusive, as is the design and location of the switch block 69 which is partially hidden by the flange 85 (FIG. 7). However, most important is the fact that, even though the panel 21 is constructed from glass, the specific blend of the polymer and the mica glass beads from which the frame-like encapsulation 30 is injection molded achieves an intimate bond between the components, absent fracture or weakening of the encapsulation 30 due to the similarities between the low shrink ratios and elasticities of these materials. Since the tempered glass panel 21 has almost a zero coefficient of expansion, there will obviously not be any material of the expansion or contraction of the same relative to the injected polymeric/copolymeric material of the encapsulation 30 at temperatures ranging between −30° F. to −140° F., temperatures which heretofore would cause injection molded polypropylene to fracture. Hence, a strong, durable and aesthetic acceptable washer lid 20 is achieved by the present invention, though usage is as other than a washer lid is well within the breadth of the present disclosure.
[0029] Although a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor variations may be made in the apparatus without departing from the spirit and scope of the invention, as defined by the appended claims. | A washer door or lid as defined by a tempered glass panel bordered by an open frame-like encapsulation of one-piece injection molded polymeric/copolymeric synthetic plastic material. The latter material is preferably acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. Further specifics of the washer lid include a relatively thick inner periphery of the encapsulation which securely grips and reinforces an outer peripheral edge of the tempered glass panel, a rigid outer peripheral skirt, an indiscrete handle, a reinforced hand corder for a switch actuator and opposite rear corners carrying hinges for securing the washer lid to an associated washer opening. | 3 |
BACKGROUND OF THE INVENTION
The field of this invention of that of liner hangers for the isolation of the well bore of oil and gas wells from the earth formations through which the oil or gas well is being drilled.
As different producing, water, and other formations through which the drilled well will pass must be isolated from each other, a casing string must be cemented in place to isolate each zone. An oil or gas well is typically drilled by first deciding the minimum bore of the production string of casing, or the last pipe to be cemented in place and will be continuous from the surface all the way down to the oil or gas producing formations. This production string of casing must be large enough to allow the production tubing landed inside it to flow enough oil or gas to make the well economic.
Each casing set point requires that an additional concentric casing string be set. A typical set of casing strings in a subsea environment from the inside out would be 7″ 9.625″ 11.750″, 13.375″, and 16″ set within an 18.750″ bore blowout preventer stack, and 20 and 30″ casing strings set before the 18.750″ bore blowout preventer stack is installed. Each casing string occupies a certain amount of radial space, requiring that the next string of pipe be progressively smaller. That program provides a maximum of 5 casing set points with blowout preventer protection during drilling.
Typically, a casing string, i.e. 11.75″ outer diameter, is installed in a drill well bore suspended from the surface to a depth such as 10,000 feet deep. After cementing the 11.750″ casing in place, a hole is drilled with a bit through the 11.750″ casing, i.e. 10.50″ diameter hole to 12,000 feet deep. Into this hole a 9.625″ outside diameter casing can be landed and cemented in place. If the 9.625″ casing string is suspended from the surface and is therefore 12,000 feet long, it is called a casing string. If, however, the 9.625″ casing is only 2000′ long and is suspended by a hanger from the lower end of the 11.750″ casing string, it is called a liner. The use of a liner can save substantially on the cost of casing and cement, e.g. 10,000 feet of casing not purchased. The well program would be followed with a 7.000″ casing string continuous from the surface to the bottom of the well as the production casing string.
The 9.625″ liner in the example above would have saved the operator the 10,000 feet of pipe not purchased, with the cost of a conventional liner hanger being generally offset by the cost of the surface casing hanger. The liner still “costs” the drilling company the “radial space”, forcing the next string to be progressively larger.
In this conventional scenario, if an unexpected pressured formation is encountered and requires that an extra casing string is set, it would probably be 5.500″ in size. With the 5.500″ size, the tubing string landed inside would be reduced from 3″ to 2″, substantially restricting the flow of production from the well. Flow from wells is especially important offshore where the high cost of drilling and producing wells demands a high flow rate to be economic. Cases have been seen of abandonment of wells when an extra pressurized reservoir zone was encountered and the driller realized that his final well bore size would be too small to be economic.
SUMMARY OF THE INVENTION
The object of this invention is to provide a liner which does not occupy “radial space” in the well bore and therefore does force each previously set casing hanger to be a step larger in diameter.
A second object of the present invention is to provide the capability of installing multiple liners in a drilling program to compensate for unforeseen well control situations.
A third object of the present invention is to provide a liner that can be rolled up for compact storage and shipment.
Another object of the present invention is to provide a liner assembly that is compact enough to be airlifted out to an offshore drilling vessel.
Another object of the present invention is to provide an expandable liner which is metallic in construction and impervious to fluid flow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a section through the oil or gas well as would remain after the previous casing string has been set and landed in place.
FIG. 2 is a section through the oil or gas well showing the bi-center bit approaching the specialized shoe.
FIG. 3 is a section through the oil or gas well showing the bi-center bit centralized and drilling within the pilot section of the existing float shoe.
FIG. 4A is a front view of the reeled liner as it would be shipped to the well site.
FIG. 4B is a side view of the reeled liner illustrating the position of the float shoe and support means.
FIG. 5 is a section showing that the liner is inserted into the well, but has not been inflated.
FIG. 6 is a section of the flattened liner as seen in FIG. 5 showing it relative size to the casing string through which it passed.
FIG. 7 is a section through a liner which has been flattened to a different pattern.
FIG. 8 is a section through the float shoe showing the means to allow for holding pressure on the first pressure cycle and then not holding pressure on subsequent pressure cycles.
FIG. 9 is a section through the liner support means.
FIG. 10 is a section showing that the liner has been expanded into an enlarged section at the lower end of the casing string.
FIG. 11 is a section through the oil or gas well showing the liner as landed, expanded and sealing in the lower end of the casing string.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, an oil or gas well 10 is shown with a subsea housing 11 at the top with a 13.625″ nominal housing bore 12 at the top. The subsea housing 11 is supported on a surface casing string 13 which penetrates the seafloor 14 . Within the housing bore 12 and on shoulder 15 a casing hanger 16 is landed. Casing string 17 having a well bore 18 extends down into the well and terminates in a casing shoe 20 .
Casing shoe 20 attached to casing string 17 by casing coupling 21 and has a landing profile 22 near its upper end. Below the landing profile is a support profile 23 , and enlarged pipe section 24 , and a float shoe portion 25 . Immediately above the float shoe portion is a standard cement annular portion 30 with a pilot bore 31 and a through bore 32 . In the bore of the landing profile 22 , the enlarged pipe section 23 , and the pilot bore 31 , a low strength material 33 is cast in place which will be usefully removed as seen further in this description.
Referring now to FIG. 2, a bi-center bit 40 is run into the enlarged pipe section. The bi-center bit includes a pilot bit portion 41 , a fixed hole opener section 42 , and a rotatable hole opener section 43 mounted on a spiral 44 . Conventionally, a special trip with a collapsible hole opener is required because a bi-center bit cannot be started within the casing due to the potential of damage to the bit. In this invention, the pilot bit is automatically centralized within the pilot bit preparation 45 to allow it to be concentric within the well prior to the beginning of rotation. The combination of this centralization and the enlarged pipe section allow for the immediate rotation of the bi-center bit without the need for a conventional hole opener run.
Referring now to FIG. 3, the pilot bit 41 is now drilling out the low strength material 33 as the rotatable hole opener section 43 contacts the top 50 of the standard cement annular portion 30 and remains vertically stationary as it rotates until the fixed hole opener section 42 catches up with it and they begin to drill the cement section together. At that time the pilot bit, rotatable hole opener section, and fixed hole opener section work together to drill out the cement shoe and continue to drill the oil or gas well deeper.
Referring now to FIG. 4, the liner of this invention is delivered to the well site on a reel 60 with a float shoe 61 near its outer end 62 and a support section 63 near its inner end 64 . The liner 65 is folded and flattened and rolled up on the reel for ease of transportation and storage. Either an 11.750″×0.250 wall×1000 ft. or a 9.625″×0.156 wall×2000 ft. liner can be airlifted for offshore service at about 30,000 lbs. The package size would be approximately 12 ft.×12 ft.×2.5 ft.
Referring now to FIG. 5, the liner is unreeled into the well bore 18 until drill string threaded connection 66 is attached to the upper thread 67 of the support section 63 . The lowering continues until expandable landing ring 68 engages landing profile 22 to position the support section 63 . The main portion of the liner 65 is in a flattened state suspended in the drilled well bore 69 .
Referring now to FIG. 6, the section through the well bore 69 and liner 65 shows that the liner has multiple folds to make it both flat and able to be rolled on a reel, and also of a smaller dimension that the hole through which it must pass. The liner is preferably of a size such that the circumference of the inner diameter when expanded to a circular shape is slightly larger than the inner diameter of the casing string through which it passed. In this style, it is effectively invisible with respect to view from the top of the well.
Referring now to FIG. 7, an alternate folding style is illustrated which yields a smaller package for entering into the well bore but somewhat more complex to fold and will tend to make a larger diameter reel for transportation.
Referring now to FIG. 8, a float shoe 61 depends from the lower end of the liner 65 , having a plug 81 with a seal 82 . Shear pins 83 hold the plug 81 in an initial position against the spring 84 . The first time the liner 65 is pressurized for inflation, the shear pins 83 shear and allow the plug 81 to move down against shoulder 85 . After the inflation pressure is released, the spring 84 will move the plug 81 out of the bore 86 and allow for cement to be circulated through the shoe to cement the liner in place.
Referring to FIG. 9, the support section 63 is shown in greater detail prior to inflating the liner 65 . After the inflation cycle and the opening of the float shoe as described above, a cementing plug (not shown) will be pumped down the bore 90 of the running string 91 until it hits shoulder 92 of cement cup 93 and pumps it to the float shoe 61 .
As the cementing plug and cement cup 93 approach the cement shoe, a support shoulder dart (not shown) is placed in the bore 90 of the running string 91 until it lands and stops on shoulder 94 . The support shoulder dart seals below the port 95 to allow high pressure from above in the running string to be vented to the inner diameter of the packer 96 . The packer expands to expand the upper section 100 of the liner 65 out to engage the profile 101 of the support section 63 . The profile 101 is made of a high yield material relative to the strength of the upper section 100 such that when the upper section 101 is expanded and released a compressive load will be retained between the surfaces.
After the upper section 100 is engaged and supported within profile 101 , the running string 91 is rotated to the right to unscrew from the connection to the top of the liner at thread 102 . Spring loaded milling cutters 103 are automatically deployed and remove any unexpanded section of the liner as the unit moves upward.
Referring now to FIG. 10, the upper end 100 of the liner 65 is supported in support profile 101 , and the milled end 110 of the upper section is seen remaining. The interface 111 between the liner upper end 100 and the support profile 101 provides for mechanical support of the liner (in addition to the cement) plus a metal to metal seal between the two parts.
Referring now to FIG. 11, a completed view of an installed invisible liner is seen after a conventional bit is used to drill out through the float shoe and continued to drill the well deeper.
The foregoing disclosure and description of this invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials as well as the details of the illustrated construction may be made without departing from the spirit of the invention. | An impervious metallic liner for the isolation of the well bore from the formations of an oil or gas well below a casing string; the liner being flattened to run through the casing string, but is inflated to occupy the space directly below the casing string rather than occupying the conventional area radially inward from the position occupied by the casing string. | 4 |
This is a nonprovisional application of prior pending provisional application Ser. No. 60/003,354, filed Sep. 7, 1995.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for severing a flexible polymeric tube, pipe, or tubular extrudate, especially an organic polymer flexible light pipe, in an uniform and clean manner, allowing for less light loss at the severed interface and for efficacious rejoining of severed segments during further processing or fabrication.
2. Description of the Prior Art
Light pipes have applications in industrial, commercial and residential lighting where it is desirable to direct light from a single source to one or more remote locations. In a light pipe system, the light is transmitted from the source to the desired location by means of one or more light pipes. Light pipes may also be referred to as optical guides or optical fibers, and vary in length and diameter depending upon particular applications. For example, light pipes made from polymeric materials may have a diameter as small as 0.001 inch (25.4 microns). The largest commercially available solid core light pipes have a diameter of about 1 inch (2.54 cm). While larger diameters of light pipes may be used, a 1 inch diameter (or less) is sufficient for most applications and light from a typical commercial light source may be readily focused onto a 1 inch light pipe. Solid core light pipes, herein abbreviated "FLP" for Flexible Light Pipe, commonly have one or more layers of light-reflective or coating materials, the light-reflective layer, often a fluoropolymer, being known as "cladding" and the protective outer coating being known as "sheathing", made of a flexible and chemically resistant material.
For making a light pipe system as versatile as possible, the FLP will often be used in multiple segments, requiring connection through appropriate coupling devices adjacent to the light source at locations where the light may be led into various branch light pipes, and finally again coupled to a lens or other device for utilizing the transmitted light for illumination.
To prepare the best couplings with the minimum loss of light whilst avoiding refractive-indexed matched liquids or adhesive in the couplings, it is necessary that the FLP have clean-cut surfaces (i.e., a flat surface with no tear marks or irregularities), usually perpendicular to the pipe (which is normally in cylindrical form--if ovoid or irregular, the cut would be perpendicular to the center line of the extended FLP.) Without extreme care, it is difficult to sever a FLP with a soft or semi-liquid core, without tearing an irregular severed area; such tearing often occurs with devices such as razor blades, knife blades in holders, blade-type "paper cutters" and the like. There exists a molded plastic apparatus, designed for severing solid rubber cylindrical stock into O-rings, with a perpendicular slit through which a razor blade may be inserted, but it does not hold the light pipe steady enough for repetitive cuts which are clean and uniform.
Matsumoto, U.S. Pat. No. 5,012,579, describes a severing machine for synthetic resin pipes which involves an improved method for applying uniform pressure to the blade during the severing process. The device appears to entail no means for tightly holding and aligning the pipe to be severed and thus assure accuracy and reproducibility during the severing process. Further, the device requires means to drive the apparatus, which makes it awkward for repetitive use in an environment where electric power is not readily available.
Thus, there is no available device which will hold the pipe in a steady manner, hold it in a form where the cut is perpendicular, and perform a rapid, clean cut with no tearing to leave a smooth perpendicular surface. Further, there is no device which can be used to sever lengths of light pipe cleanly and with good reproducibility of length. The present invention overcomes the above stated problems.
STATEMENT OF THE INVENTION
We have developed such a device for severing a flexible polymeric tube, pipe, or tubular extrudate, preferably a flexible polymeric optical light pipe, to yield reproducibly a clean cut perpendicular to the surface of the linearly extended flexible polymeric light pipe. The severed flexible optical light pipe is suitable for optical re-coupling. The severing device comprises:
a) means for holding the linearly extended flexible polymeric light pipe to be severed so that the surface of the light pipe is perpendicular to the plane swept by the severing means, said holding means not interfering with the path of the severing means, said holding means comprising:
(1) two hollow cylinder blocks of a diameter larger than that of the linearly extended flexible polymeric light pipe to be severed, said cylinder blocks mounted so that the diameter line of one cylinder block when extended is the diameter line of the second, said opposing faces of said cylinder blocks being separated by a distance slightly larger than the thickness of the blade, preferably the difference between the thickness of the blade and the width of the distance being from about 0.001 to 0.010 inches;
(2) a collet inserted in each cylinder block, each collet having an outer diameter slightly smaller than the inner diameter of the cylinder and an inner diameter slightly larger than the linearly extended flexible polymeric light pipe to be severed, said opposing faces of said collets being separated by a distance slightly larger than the thickness of the blade, preferably the difference between the thickness of the blade and the distance being from about 0.001 to 0.010 inches;
(3) means for tightening the cylinder block to the collet, so that the collet is immobilized within the cylinder block;
(4) means for tightening the collet to the flexible polymeric light pipe, so that the linearly extended flexible polymeric light pipe is immobilized within the collet;
b) severing means comprising a blade of sufficient sharpness to sever cleanly the linearly extended flexible polymeric light pipe and a blade holder for said blade which clamps the blade securely, said blade being of a thickness slightly smaller than the distance between the opposing faces of the collets or cylinder blocks, said blade being of a size of exposed severing edge at least that of the diameter of the linearly extended flexible polymeric light pipe to be severed, said blade holder having a portion in the shape of a handle, said holder having an exposed area for the blade surface adjacent to said severing edge at least that of the diameter of the linearly extended flexible polymeric light pipe to be severed, said blade holder having means to attaching to a pivot mount so that it may be moved in a plane perpendicular to that of the pivot;
c) a mounting for said severing means comprising a pivot mount, having a pivot, and a baseplate, said baseplate being capable of being tightly fastened to a solid surface, said pivot mount being aligned parallel to the diameter of the linearly extended flexible polymeric light pipe after clamping and holding the linearly extended flexible polymeric light pipe, said pivot mount attaching to said blade holder through said attaching means, said pivot mount being located at a point in the block wherein the plane swept by the exposed blade on said severing means will engage the complete cross-sectional area of the cylinder or collet in the space between the opposing faces of said cylinder blocks or collets.
The apparatus described herein, as illustrated by the drawings, is a specific embodiment of the broader invention; it will be apparent that alterations can be made in the design to accommodate the full inventive concept of the device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 through 3 show a first embodiment, FIG. 1 being a side view, FIG. 2 being a top view, and FIG. 3 being a sectional view taken on section line II--II of FIG. 2 with a flexible polymeric light pipe (110) mounted therein; FIG. 4 is a top view of a base plate (1); FIG. 5 is a blade (14); FIGS. 6 through 8 are, respectively, a top view, a side view, and a front view of a pivot mount (2); FIGS. 9 through 11 are, respectively, a side view, a bottom view, and a side view of a blade holder (13); FIGS. 12 through 14 are, respectively, a top view, a front view, and a side view of a cylinder block (19); FIG. 15 is a top view of a collet (23).
DESCRIPTION OF THE PREFERRED EMBODIMENT
One embodiment of the device is shown in FIGS. 1 through 15. The term "collet" is used in the dictionary sense of "a collar or enclosing band, specifically, a slotted cylindrical clamp inserted into the interior of a sleeve", so that the collet (23), having a flat end (124), is sized externally to fit within the cylinder block (19), having a flat end (124), and internally so as to allow insertion of the flexible polymeric light pipe (110) and to fit firmly around the flexible polymeric light pipe (110), further with means to tighten further upon the flexible polymeric light pipe (110) by means of external pressure. The advantage of the collet (23) over direct insertion of the flexible polymeric light pipe (110) into the cylinder block (19) and applying tightening pressure to hold the flexible polymeric light pipe (110) steady is that the collet (23) is sized close enough to the size of the flexible polymeric light pipe (110) that the flexible polymeric light pipe (110) is already held tightly without distortion of the cross-sectional area, and the pressure of one or more tightening devices to hold it very steady will not distort the flexible polymeric light pipe (110) further.
Preferred embodiments of the invention involve the use of a blade (14) which is coated with a lubricating fluoropolymer (not shown), such as polytetrafluoroethylene. Such a coating, which includes any coating or film having a low coefficient of friction, avoids the need to apply an external lubricant frequently. For ease and safety of replacement, a single-edge razor blade is preferred, and especially preferred, for ease of clamping securely, is a razor blade (14) which contains a reinforcing strip (14b) across the top of the blade (14), and a severing edge (14c) of the blade being at the bottom.
To hold the blade (14) immobile, it is preferred further that the blade holder (13) contains means, such as tightening bolts (106), for applying pressure perpendicular to the razor blade surface to render said blade (14) immobile relative to the blade holder (13).
For best control to tightly mount the severing blade (14), it is preferred to use a razor blade which contains notches (14a) at each side of the blade (14), said notches (14a) being centered from about one-fourth to about three-fourths of the distance between top and bottom of the blade (14). Such notches (14a) are engaged in the blade holder (13) by tightening bolts (106).
As designed, the blade holder (13) is constrained to pass the blade (14) through a narrow passage (122) between the collets (23) which hold the linearly extended flexible polymeric light pipe (110) in a fixed manner, and the blade holder (13) is constrained to swing in an arc (not shown) which allows the severing edge (14c) to descend upon and cleanly slice the linearly extended flexible polymeric light pipe (110) to be severed, but which is constrained by the design of the blade holder (13) so that the severing edge (14c) does not contact the base plate (1) with resultant dulling of the severing edge (14c).
Although designed to sever flexible polymeric light pipe which is a soft, flexible, sometimes semi-liquid core surrounded by a thin cladding of reflective polymer, such as a fluorocarbon polymer, and further usually surrounded by a protective sheath of a relatively tough plastic, such as polyethylene, the device may also be used to sever other objects, such as elastomers, rubber tubing, plastic tubing, and the like, which are difficult to cut without tearing or spoiling the surface exposed by the severing. The device further alleviates the need to chill the object prior to cutting or severing.
If it is desired to make a clean cut at an angle other than perpendicular to the alignment within the cylinder blocks (19) of the flexible polymeric light pipe (110) to be cut, the device may be further transmogrified so that the narrow passage (122) is angled in such a way that the plane of the cut (not shown) produces an angled cut (still perpendicular to the surface) or an angled cut which is no longer perpendicular to the surface of the flexible polymeric light pipe (110). The former will involve mounting the cylinder blocks (19) so that the narrow passage (122) between the two cylinder blocks (19) or the two collets (23) (to be filled by the linearly extended flexible polymer light pipe (110) to be cut) is not perpendicular to the plane (not shown) traversed by the blade (14), which in turn will involve modifying the angles of the flat ends (124) of the cylinder blocks (19) and collets (23) to allow clean passage of the blade (14) without excessive widening of the narrow passage (122) between the two flat ends (124).
The latter will require altering the nature of the pivot mount (2) and/or the mounting of the cylinder blocks (19) and also probably the location and angle of the pivots (not shown); for most purposes, it will suffice to mount the two cylinder blocks (19) on the base plate (1) in such a way that the narrow passage (122) between the two cylinder blocks (19) or the two collets (23)(to be filled by the linearly extended flexible polymeric light pipe (110) to be cut) is aligned such that the desired angle cut (not shown) is formed upon passage of the blade (14). The geometry of the ends of the cylinder blocks (19) and collets (23) adjacent to the severing area will require modification (not shown) to allow passage of the blade (14); also, the cylinder blocks (19) may be bored at an angle which is not perpendicular to the plane (not shown) of the blade (14). Appropriate design adjustments to the device described below may readily be calculated. Elements of the mounting used in compound miter saws (not shown) may be employed in such a design, as may the use of a swivel on the base plate (1) to move the cylinder blocks (19) to an appropriate angle (not shown), and then controlling the width of the narrow passage (122) by collet design.
It is also possible to design the collet (23) in such a way that it is also useful as part of the assembled flexible polymeric light pipe (110). For example, the collet (23) at one end (not shown) would insert into the cylinder blocks (19) for controlling the cutting of the flexible polymeric light pipe (110), while the other end (not shown) would be designed to fit into an appropriate holder to place and hold the flexible polymeric light pipe (110) in a desired position relative to an illuminator (source of light, not shown) or the area to be illuminated (not shown).
FIGS. 1 and 2 show the severing device (120) of the present invention, which is the blade holder (13) and blade (14) mounted together and installed on a mounting (not shown separately) for the blade (14) and blade holder (13), the mounting (not shown separately) comprising the pivot mount (2) and the baseplate (1); FIG. 3 further shows the means for holding the flexible polymeric light pipe (110) to be severed mounted on the baseplate (1), the means for holding comprising two hollow cylinder blocks (19), two collets (23) for the cylinder blocks (19), tightening means such as polyacetal screws (102) for tightening the cylinder blocks (19) to the collets (23), and tightening means such as polyacetal screws (104) for tightening the collets (23) to the flexible polymeric light pipe (110). Each portion will be described in detail.
The base plate (1), is machined from 6061 aluminum of dimensions 4 inches by 6 inches by 0.25 inches. A rubber pad (100) may be affixed to the bottom, or clamps (not shown) may be applied at the corners for better fastening to a fixed surface (not shown). The pivot mount (2) is mounted to the base plate (1) near edge (1a) through two 10/32 screw holes (3a) and (4a) (see FIG. 6) and associated holes (3) and (4) for cap screws (5) drilled in the base plate (1) 0.25 inch and 1 inch from the end and 1.489 inch from one side. The pivot mount (2) is an "L" shaped piece of 1/4 inch aluminum, having a bottom (2a) 1.25 inches deep×0.75 inches wide, into which is drilled two 10/32 screw holes (3a) and (4a) to fasten base plate (1) and pivot mount (2) together. The pivot mount (2) has an upright portion (2b) and stands 1.5 inches high. The two pieces are fastened together by cap screws (5) though holes (3) and (4); see FIGS. 6 through 8 which illustrate the configurations of the pivot mount (2)for the blade holder (13).
Into the surface of the longer and upright portion (2b) of the L-shaped pivot mount (2) is drilled and tapped a 10/32 inch hole (6a) into which will be inserted a nylon ball plunger (7) which then will be held in place by a lock nut (8). The nylon ball plunger (7) will protrude just far enough to lock into place with one of three depressions (17) milled into the blade holder (13), so as to lock it in position, as will be described below. Hole (6a) is drilled 0.75 inches from the bottom (2a) of the pivot mount (2) and 0.50 inches from the edge (2c) of the pivot mount (2) at the edge of the base plate (1a); see FIG. 8.
For safety purposes, so as to block the blade holder handle (13a) from being raised too high and so exposing the blade (14), a cap screw hole (9) is bored in the upper corner nearest the base plate edge (1a) of the pivot mount (2). When a cap screw (not shown) is inserted into this cap screw hole (9), the blade holder (13) cannot be lifted above a 45° angle, and the blade (14) is less exposed. The cap screw (not shown) can be removed to pivot the blade holder (13) fully for removal of the blade (14) or cleaning of the blade (14) and blade holder (13).
A 0.25 inch pivot hole (10) with screw tapping (not shown)is drilled into the surface of the longer and upright portion (2b) of the L-shaped pivot mount (2) at a point 0.75 inches from the bottom (2a) of the pivot mount (2) and 0.875 inches from the edge (2c) of the pivot mount (2) mounted at the edge (1a) of the base plate (1). Through this pivot hole (10) and an aligned hole (112) in the blade holder (13) (see FIG. 9) will be placed a shoulder screw (12) on the side of the blade attachment part of the blade holder (13b) which can be tightened to hold the blade holder (13) firmly on the pivot mount (2), yet allow motion of the blade holder (13) in a severing plane (not shown). The shoulder screw (12) has a screw thread (not shown) at the end, a larger shank (not shown)which is just slightly longer than the width of the blade holder (13), and a shoulder (not shown) with an inset head (not shown); when the shoulder screw (12) is inserted, pivoting is constrained by the ending of the screw thread portion and the larger width of the shoulder portion to keep the blade holder (13) pivoting in a narrow plane.
The blade holder (13)--see FIGS. 9 through 11, which illustrates the blade holder (13)--is machined from 6061 aluminum. It is 7.5 inches long, and 0.38 inches thick. The arm of the holder (13a) which is used for severing and which extends from the edge of the razor blade (14) to the end is 5 inches long and 0.56 inches high. The blade attachment part of the blade holder (13b) is 2.0 inches high and 2.75 inches wide. A triangular portion (16a) cut 1 inch from the edge is removed; the lower left corner is rounded with a 0.5 inch radius (not shown). The blade (14), such as a razor blade, fits into the bottom edge where a blade recess (15) 0.10 inches deep has been cut into the blade attachment part of the blade holder (13b) on the side (13c) which will be mounted away from the nearest edge. This blade recess (15) is 1.58 inches long and 0.8 inches high. Behind the blade recess (15) are drilled two 4/40 taps (16) for fastening bolts (106) which tighten on the blade (14) at the blade notches (14c) to hold it firmly in place. The cut-out (15b) for the blade recess (15) is cut through the depth of the blade attachment part of the blade holder (13b). The cut-out (15b) is shaped so as to be as large as the largest piece of light pipe to be cut, so that only the severing edge (14c) sweeps through the narrow passage (122) allocated for the severing operation. The cut-out (15b) is also shaped slightly off center, so when the severing edge (14c) is worn down, the blade (14) can be reversed in the blade holder (13b) and re-used.
The blade (14) is a commercially available single-edge razor blade, coated with polytetrafluoroethylene--see FIG. 5. The blade (14) is 1.5 inches in length, and 0.75 inches high. Its thickness is 0.009 inches. Notches (14a) have been cut by the blade manufacturer in both sides 0.625 inches from the bottom or severing edge of the blade. A reinforcing strip (14b), added by the blade manufacturer, is attached to the blade (14), of height about 0.238 inches and of thickness about 0.015 inches. A hole (14d) is in the center of the blade (14). As noted above, the blade recess (15) width and height are so constructed that the blade (14) can be easily inserted and removed, but can be tightened firmly in place by the bolts (106), which fit though the notches at 14a.
For safety and to hold the blade holder (13) in various positions, there are machined into the blade attachment part of the blade holder (13b) three depressions (17) which are at angles of 0°, 45°, and 90° to the position of the blade holder (13) when the blade holder handle (13a) is parallel to the base plate (1). These depressions (17) are machined at a distance equivalent to the distance between holes 6 and 10. The nylon ball plunger (7) will then engage one of the depressions (17) so as to hold the blade (14) at one of three angles (not shown), but allow it easily to be released for severing purposes.
When fastened into the blade recess (15), and when the blade holder handle (13a) is parallel to the base plate (1), i.e., when the blade (14) has been lowered to pass through the narrow passage (122), the severing edge (14c) of the razor blade (14) will not touch the base plate (1), as the blade recess (15) is so machined that the severing edge (14c) of the blade (14) is slightly above the bottom edge (13c) of the blade holder (13).
Into the base plate (1) are drilled eight holes (18a through 18h) to hold the cylinder blocks (19) for the flexible polymeric light pipe (110) to be cut. The first set (18a to 18d) at edge (1a) of the base plate (1) where the pivot mount (2) is mounted comprise a rectangle 0.875 inches along the longer edge of the base plate by 0.65 inches along the narrower edge of the base plate (1). The holes (18a and 18b) closest to the pivot mount (2) are 1.375 inches from the narrower edge (1a) of the base plate (1) and 1.00 inch (18a) and 1.65 inches (18b), respectively, from the longer edge (1b) of the base plate (1). The second set (18e-18h) at the opposite side of the base plate (1) where the pivot mount (2) is mounted comprise a rectangle 0.875 inches along the longer edge (1c) of the base plate (1) by 0.65 inches along the narrower edge (1a) of the base plate (1). The holes (18e and 18f) closest to the pivot mount (2) are 1.375 inches from the narrower edge (1a) of the base plate (1) and 1.312 inches (18e) and 0.662 inches (18f), respectively, from the longer edge (1c) of the base plate (1).
The cylinder blocks (19) are attached to the base plate (1) by screws (114) which are tightened into the baseplate holes (18a through 18h) through vertical holes (116) drilled vertically at the same dimensions as the patterns of holes (18a through 18h). Screws (114) of sufficient length to allow manual tightening and loosening pass through the vertical holes (116) to the tapped holes (18a through 18h) . The cylinder blocks (19) are illustrated in FIGS. 12 through 14.
The cylinder blocks (19) are made from polyacetal resin and are 0.75 inches high by 1.68 inches wide by 1.12 inches deep, except that at the edge which faces the severing area, there is an cylindrical extension (20) which is 0.28 inches long and 0.52 inches in diameter, the cylindrical extension (20) being centered over the center of a drilled cylindrical hole (21). (If desired, the portion of the cylinder block (19) not pierced with the cylindrical hole (21) may be machined off (not shown) to leave only a base portion (not shown) for fastening via set screws in holes (18a through 18h). The cylindrical hole (21) is bored with its center 0.56 inches from the sides and 0.291 inches from the bottom face (which sits on the base plate (1)). This cylindrical hole (21) is of diameter 0.384 inches. The portion of the cylinder block (19) within the cylindrical extension (20) is slightly flared as a chamfer of 0.03 inches by a 45° angle (not shown).
In the top of a cylinder block (19) is drilled a vertical tapped hole (22) which is located 0.84 inches from the face edge of the cylindrical extension (20) (0.56 inches from the rear face). Into this 10/32 vertical tapped hole (22) is inserted a polyacetal screw (102) which may be turned by hand to exert pressure on the collet (23) inserted in the cylindrical hole (21) and keep the collet (23) from moving. Multiple holes and screws could be utilized for this purpose, or some method which would exhibit uniform pressure on the collet (23) could be employed (not shown).
As the cylindrical hole (21) is of fixed size (9.75 mm.) whereas the flexible polymeric light pipe (110) to be cut will be of several sizes (e.g., 3, 5, 7, or 9 mm.), various collets (not shown) are employed. These collets narrow the diameter of the cylindrical hole (21) which holds the flexible polymeric light pipe (110) to a value just large enough to allow easy insertion and removal, and only slight additional pressure by a tightening device (not shown) to hold the flexible polymeric light pipe (110) steady in the collet (23), which in turn is held steady in the cylinder block (19) by a screw (22).
A typical collet (23), as illustrated in FIG. 15, is machined from an aluminum cylinder (23a) with a hole (not shown) inside, the outer diameter of the aluminum cylinder (23a) being just smaller than the diameter of the cylindrical hole (21). At the end of the collet (23) away from the narrow passage (122) is present a shoulder (24) which is 0.5 inches long and 0.5 inches in diameter. The aluminum cylinder (23a) of the collet is 1.41 inches long, which is just slightly longer than the length of the cylindrical hole (21). The collet (23) may be manufactured from one piece of aluminum pipe, rather than attaching a separate sleeve (not shown). The interior diameter of the collet is 5 mm. (0.197 inches).
In the shoulder (24) is tapped a vertical hole (25) which is located 0.25 inches from the rear edge of the shoulder (24). Into this 10/32 vertical hole (25) is inserted a polyacetal screw (104) which may be turned by hand to exert pressure on the flexible polymeric light pipe (110) inserted in the collet (23) and keep the flexible polymeric light pipe (110) from moving. Multiple holes (not shown) and screws (not shown) could be utilized for this purpose, or some method which would exhibit uniform pressure on the flexible polymeric light pipe (110) could be employed.
In practice, the device is assembled and it is determined that the centers of the cylindrical holes (21) are aligned, and that the narrow passage (122) between the facing edges of the collets (23) is sufficient to allow the severing edge (14c) of the razor blade (14) to pass through that narrow passage (122) upon lowering the blade holder handle (13a). The blade holder handle (13a) is then raised 45°, a piece of 5 mm flexible polymeric light pipe (110) is inserted through both collets (23), the polyacetal screws (102) and (104) are tightened, and the blade holder handle (13a) is lowered to cause the blade (14) to sever the flexible polymeric light pipe (110). A clean cut on both surfaces is observed (not shown).
The severing edge (14c) ay be the conventional shape as found in a commercial razor blade, where the two severing surfaces taper inwards at equal angles (not shown). These tapering edges may be slightly beveled. However, although well adapted for shaving, these blades do not give the best perpendicular cut for the cleanest surfaces, although the cuts are adequate for most purposes.
An improvement is to shape the blade so that one side of the blade is extended in a straight line in the plane of the cutting stroke, and the other edge is tapered to the desired cutting edge thickness (not shown). When mounted in the blade holder (13), the straight edge will face the portion of the flexible polymeric light pipe (110) which requires the best surface (not shown). For example, if the severing device is used to trim the end of a piece of flexible polymeric light pipe (110) prior to re-connection, then the flat edge of the blade not shown) will contact the new end cut on the flexible polymeric light pipe (110), while the tapered edge (not shown) faces the small end piece (not shown) which is removed and discarded.
Various other attachments may be made, such as means for measuring a specific length of light pipe to be cut. The device may be used to sever flexible light pipe which does not have an external protective sheathing. The device may be used to sever a bundled flexible light pipe, i.e., where several light pipes are bundled together within a single protective sheath. | A device for severing flexible polymeric tube, pipe, or tubular extrudate, such as flexible light pipe, reproducibly, cleanly, and safely is described. The device comprises a block with two specially aligned cylindrical devices for holding the pipe and a slot between the devices for guiding the severing blade with minimum deviation from its path, and a pivot and mounting upon which a blade in a holder is mounted to give even more accurate and uniform control of the path of the severing action. | 8 |
FIELD OF THE INVENTION
The present invention relates to arc welding torches and particularly to welding torches of the Gas Metal Arc Welding ("GMAW") type in which the barrel carrying the welding tip can be readily removed or rotated to any desired angular position.
BACKGROUND OF THE INVENTION
GMAW welding torches typically comprise a mounting block adapted to be manipulated by a welder's hand or a robotic manipulator, made of current conducting material such as aluminum or a copper alloy. A current conducting barrel, having a welding tip at the remote end thereof, is generally inserted into a socket formed in the block. The barrel is secured in the block by means of bolts which squeeze two sides of the block, separated by a slit, together adjacent the entrance to the socket. The mounting block transfers a consumable electrode or welding wire, weld current, inert gas and generally a coolant fluid such as water, from a stationary location, e.g., a cabinet, to the barrel. The barrel is provided with appropriate passageways or channels for conducting such materials to the welding tip. See U.S. Pat. No. 4,954,690 which describes the GMAW torch sold by the assignee of this application, M. K. Products, Inc., under the trademark Prince®. The Prince® torch does not provide a coolant liquid to the barrel. Also see U.S. Pat. No. 5,549,068 which describes another torch marketed by M. K. Products under the trademark King Cobra®. The latter torch, which is water cooled, utilizes intermediate barrel mounted to the block for holding the torch barrel.
Torch barrels may be straight or curved depending upon the type of welding to be accomplished and the preferences of the welder. It is often necessary or highly desirable for an operator to be able to change the angular position of a curved barrel relative to the block to accommodate a robotic manipulator or to configure the torch so that it is more ergonomically compatible to a welder's hand manipulations.
The barrels in both of the above prior art torches can be rotated. However, a proper tool is used to remove the cover and adjust the angular position of the '690 torch. An angular adjustment of the barrel in the '068 torch can be readily accomplished by hand. However, the intermediate barrel (referred to in the '068 patent as the main barrel) constitutes not only an additional element, but an element that is expensive to manufacture in view of the bayonet connections (22a and 22b, FIG. 3) for the cooling water. In addition, arcing can occur between metallic collet fingers (100, FIG. 5) and the welding tip barrel mounting structure (34, FIG. 3) of the '068 torch if the operator fails to insure that the collet nut 20 is rotated to its tightened stop position.
There is a need for an improved GMAW torch assembly which allows an operator to readily rotate a weld tip barrel (particularly of the curved type) without disturbing the feed wire, gas and coolant connections while insuring that a reliable current carrying connection between the barrel and block is maintained after the rotation has been accomplished.
SUMMARY OF THE INVENTION
A welding torch, in accordance with the present invention, includes a mounting block assembly of current conducting material, such as aluminum or a copper alloy, having a cylindrical open-ended receiving socket with a proximal end adjacent the opening and a distal interior section. The mounting block is adapted to be connected to a welding current source and includes passageways opening into the distal section of the socket for supplying welding wire, coolant and inert gas to passageways in the mounting end of a current conducting elongated torch barrel inserted into the socket. A current carrying split collar is slidable along the outer surface of the torch barrel for insertion into and extraction from a seated position in the proximal end of the socket. Preferably the collar is carried by the torch barrel. The collar, in its seated position, is wedged between the inner surface of the proximal end of the socket and the outer surface of the barrel to carry welding current therebetween and to maintain the barrel in a fixed position relative to the block. The collar, in its unseated position, permits the torch barrel to be rotated without disturbing the wire, gas and coolant connections or removed entirely from the mounting block. A manually operable assembly, such as a nut and a cooperating threaded portion on the block allows an operator to move the collar along the barrel to its seated or unseated position.
The construction and features of the torch assembly of the present invention may best be understood by reference to the following description taken in conjunction with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view, partially broken away, of the mounting block assembly and torch barrel of the present invention;
FIG. 2 is an enlarged exploded view of a split collar and an insertion/extraction nut subassembly for securing the barrel to the mounting block;
FIG. 3 is a cross-sectional view of the mounting end of the torch barrel seated in the receiving socket of the mounting block assembly; and
FIG. 4 is a side elevational view, partially broken away, of the mounting block assembly with the mounting end of the torch barrel seated therein.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, a GMAW welding torch or gun is illustrated (FIG. 1) which can be manually manipulated or mounted on a robotic manipulator. The gun includes an insulated housing 10, the upper portion 12 of which encloses a current conducting mounting block 14 (shown in FIG. 3). The housing includes a lower portion which forms a pistol grip for accommodating an operator's hand and encloses an electric motor (not shown). The motor pulls a consumable wire electrode 18 via a gear drive 20 (FIG. 4), from a spool of wire carried by the gun or from a stationary location, such as a cabinet (not shown), containing a spool of welding wire and supplies of welding current, inert gas and coolant fluid. A hand operated lever 17 conventionally controls a potentiometer/switch arrangement (not shown) to operate and control the speed of the motor. Coolant fluid, generally water, is supplied to the mounting block through the power cable sheath 22 and returned to the cabinet (or a sink) through a conduit or hose, such as 24. Inert gas is supplied to the block 14 through a conduit or hose, such as 26. Power for the wire pull motor may be supplied through a cable, such as 28. The conduit 30 houses the weld wire 18.
The mounting block 14, along with a forwardly extending frusto-conical-barrel-mounting sleeve or collet 34, having an integral flange 34a, is bolted to the block 14 via bolts 34b. The block 14 and sleeve 34 form a mounting block assembly. Both the block 14 and the sleeve are manufactured from a current conducting material with the block generally made of aluminum and the sleeve being made of a brass or copper alloy. The block assembly is provided with a cylindrical open-ended receiving socket which includes a distal section, indicated generally by the bracket 36 in FIG. 3, and a proximal end formed by the interior of the sleeve 34. It is to be noted that while the sleeve is illustrated as a separate piece, it may be formed integrally with the block 14. The block 14 is formed with annular channels 38, 40 and 42 and passageways 38a, 40a and 42a for providing coolant fluid and inert gas to the torch barrel as will be more fully described.
The barrel structure includes a curved cylindrical barrel member 44 (FIG. 1) made of a suitable current conducting material such as a copper alloy, which carries a welding tip 48 at the other end. The welding tip is conventional and includes a shroud 49 surrounding a wire guide 50 through which the consumable electrode is fed to the welding site. The shroud 49 is cooled by coolant channeled through the barrel and is insulated from the current conducting barrel to eliminate arcing between the shroud and the work piece. The barrel may also be covered by an insulating sheath. Inert gas from the mounting block flows through a separate passageway in the barrel (not shown) and exits in the space between the wire guide 50 and the shroud 49. It should be noted that the barrel member may be straight instead of curved, in which case there is no need to rotate the barrel after installation.
The mounting end 46 of the barrel is arranged to be axially inserted into the receiving socket of the mounting block assembly as is illustrated in FIG. 3. The distal section of the receiving socket is provided with an inwardly projecting abutment 52 which registers with a shoulder 54 when the mounting end of the barrel is in seated and registered position in the socket. The mounting end of the barrel is provided with peripheral grooves 56, 58 and 60 which are aligned with the socket channels 38, 40 and 42, respectively, when the barrel is seated within the socket.
A passageway, within the barrel (not shown) conducts the inert gas from the channel 56 to the welding tip. Additional passageways within the barrel (not shown) conduct coolant fluid from one of the channels 58, 60 to the shroud and back to the other channel in a conventional manner. The coolant, e.g., water, circulates to the very front of the shroud or cup 49 and circulates around the shroud to cool the same and then returns back to the barrel passageways. Protrusions 61 in the shroud conduct the coolant to and from the barrel. O rings 62 extend between retaining recesses in the mounting end of the barrel and the socket wall to maintain the several fluids within their assigned channels.
A current conducting split collar 64, made for example of a brass or copper alloy, cooperates with the mounting block sleeve or collet 34 to secure the mounting end of the barrel in the block assembly socket and prevent relative movement therebetween. The collar 64 has a substantially cylindrical inner surface and an outer surface which tapers at a small angle within the range of about 1° to 5° and preferably about 2° toward the insertion end 64b as is illustrated in FIG. 3. The taper, designated by the bracket 64b in FIGS. 2 and 3, mates with a corresponding taper on the inner surface 34d of the sleeve 34. The cylindrical inner surface of the collar is arranged to slide axially along the outer surface of the mounting end 46 of the torch barrel 44. The collar 64 is arranged to be carried by the barrel, although it could be carried and remain a part of the mounting block assembly.
The collar 64 is provided with an outwardly projecting flange 64c and a snap ring receiving groove 64d into which a snap ring 68 is arranged to be seated. A collar-insertion/extraction nut 70 cooperates with the externally threaded forward end 34c of the sleeve 34 to insert and extract the split collar from a seated position in the sleeve as will be explained more fully.
The insertion/extraction nut 70 includes an inwardly projecting shoulder 70a which is captured between the flange 64c and the snap ring 68. A knurled cap 72 made of insulating material is press fitted over the nut 70.
The torch is assembled by inserting the mounting end of the torch barrel, with the insertion/extraction nut 70 (including cap 72) and collar 64 positioned thereon, into the receiving socket of the block assembly until the shoulder 54 engages the socket abutment 52. The collar 64 and nut 70 are then slid along the barrel until the nut engages the threads on the sleeve 34. When the barrel has been turned, to provide the desired angular relationship between the mounting block assembly and the weld site or workpiece, the nut 70 is driven along the threads on the sleeve until the barrel is firmly secured in the block assembly. In the secured or seated position, the collar is wedged between the outer surface of the barrel and the inner surface of the sleeve 34 to prevent relative movement between the barrel and block assembly and to provide a continuous and reliable path for the welding current. When the rotational direction of the nut 70 is reversed the shoulder of the nut engages the snap ring and pulls the collar forwardly of the sleeve 34. This action unseats the collar and allows the barrel to be rotated relative to the block assembly without disturbing the gas, wire and coolant connections since the mounting end of the barrel remains seated in the distal end of the socket. When the collar is unseated the mounting end of the barrel may also be manually removed from the block assembly.
There has thus been described a novel GMAW type welding torch which allows an operator or welder to rotate the torch barrel to a desired angular position without disturbing the fluid and wire connections while insuring that a reliable current path to the barrel is maintained after the rotation has been completed. Various modifications and improvements will become obvious to those skilled in the art without involving any departure from the spirit and scope of the invention as covered by the appended claims. | An arc welding torch includes a current conducting mounting block which provided with an open-ended socket for receiving the mounting end of a current conducting removable and rotatable barrel having a welding tip at the free end thereof. Welding wire, inert gas and coolant are supplied to the welding tip via passageways in the block and barrel. A current carrying split collar is slidable along the barrel and adapted to be wedged between the barrel and the inner surface of the socket adjacent the open end thereof via a nut which engages threads on the block to maintain the barrel in a seated and fixed position in the socket. | 1 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The invention relates to a vehicle driving unit which employs a driving source formed by combining a combustion engine (hereinafter referred to as an engine) with a motor generator and a multi-stage automatic transmission for accomplishing a plurality of speeds. More specifically, the invention relates to a control system of the vehicle driving unit.
2. Description of Related Art
Generally employed vehicle driving units include a hydraulic driving unit which combines a driving source formed of an engine and a motor generator with a multi-stage automatic transmission. The motor generator of the driving unit of this type can be used as a generator which recovers braking energy from wheels and accumulates it as electric power. The motor generator is driven by the accumulated power to start the engine and drive the vehicle.
As previously designed, the aforementioned hybrid vehicle driving unit may use a torque converter as a starting device which inputs a driving torque of the driving source formed by the engine and the motor generator into the automatic transmission. Alternatively, a power split device formed by combining a planetary gear with a clutch can be used in the driving unit of the aforementioned type.
Unlike the torque converter, the power split device does not retard revolution change resulting from fluid slippage when the automatic transmission performs a shift operation while the engine is being driven. As the input revolution changes, the inertia torque generated by an inertia moment at the front side of the transmission such as an engine and a fly wheel during the shift operation is directly input to the transmission. On the other hand, the input inertia torque is rapidly absorbed by the engaging elements at the end of the shift operation. Such a sharp change in the torque may cause a great shift shock.
However, a shift shock resulting from rapid absorption of the inertia torque, though on a relatively small level, occurs also in a generally employed multi-stage automatic transmission provided with a general torque converter having only an engine as a driving source. In order to eliminate the aforementioned shift shock, the generally employed automatic transmission is provided with various kinds of devices for controlling an engagement hydraulic pressure applied to the friction engagement elements. In case of following the general solution as aforementioned to eliminate the shift shock which occurs in the hybrid vehicle driving unit, the engagement pressure applied to the friction engagement elements is decreased immediately after the end of the shift operation to reduce a rate of the revolution change. This may prevent the output torque from sharply declining.
FIG. 7 is a timing chart showing the relationship between characteristics of an engagement hydraulic pressure (Pa) of the friction engagement elements, an engine revolution (Ne) and a transmission output torque (Tout). It is assumed that the engagement hydraulic pressure (Pa) of a clutch or a brake as the friction engagement element decreases from the level of the general characteristic shown by a chain line to the level shown by a solid line at a later stage of the engagement phase as the arrow indicates. Then, a sharp decline of the transmission output torque (Tout) resulting from absorption of the inertia torque shown by a chain line can be modified to a gentle decline shown by a solid line.
In the case where the aforementioned method is adopted to inhibit the shift shock resulting from absorption of the inertia torque, the transmission output torque (Tout) characteristic may cause the time required for the shift operation to be longer by (t) than the case where generation of the inertia torque is not retarded as shown by the chain line. Accordingly, the time period during which the friction engagement elements slip is extended by the time (t). This may adversely affect the durability of the friction materials constituting the respective elements.
SUMMARY OF THE INVENTION
A first object of the invention is to provide a control system of a vehicle driving unit employing a driving source formed of an engine and a motor generator, which eliminates a shift shock by preventing a sharp decline of a transmission output torque at the end of a shift operation without extending the time required for the shift operation.
A second object of the invention is to prevent the sharp decline of the transmission output torque in accordance with an inertia torque input to the automatic transmission.
A third object of the invention is to keep a decrease rate of the transmission output torque constant in order to prevent the aforementioned sharp decline.
A fourth object of the invention is to cause a motor generator to apply a torque (torque assistance) in accordance with the inertia torque input to the automatic transmnission.
A fifth object of the invention is to reduce the inertia torque itself input to the automatic transmission system.
In order to accomplish the first object, there is provided a control system of a vehicle driving unit which employs a driving source formed by combining an engine with a motor generator, and a multi-stage automatic transmission for accomplishing a predetermined speed by engagement of friction engagement elements. The control system includes shift operation termination determination means for determining the time until the shift operation is terminated and torque output command means for generating a torque output command to the motor generator based on a determination of the time left until termination of the shift operation made by the shift operation termination determination means such that an output torque decreases gently from a predetermined torque value.
In order to accomplish the second object, the control system includes input revolution detection means for detecting an input revolution of the automatic transmission and inertia torque calculation means for calculating an inertia torque input to the automatic transmission during a shift operation based on a change in input revolution detected by the input revolution detection means. A predetermined torque is defined as an output torque corresponding to the inertia torque calculated by the inertia torque calculation means.
In order to accomplish the third object, the control system includes a torque decrease rate setting means for setting a rate at which an output torque decreases gently, and based on a decrease rate set by the torque decrease rate setting means, the torque output command means sends a torque output command to a motor generator such that the output torque decreases at a constant rate every time a shift operation is performed.
In order to accomplish the fourth object, the control system includes output command selection means for comparing an inertia torque during a shift operation calculated by inertia torque calculation means with a predetermined inertia torque value, and for stopping transmission of an output command from the torque output command means when the calculated inertia torque is equal to or less than the predetermined value.
In order to accomplish the fifth object, the torque output command means generates a torque output command (S24) such that an output torque of the motor generator becomes negative during a shift operation.
The invention allows the output torque after the end of the shift operation to be reduced gently by torque assistance of the motor generator. As a result, the shift shock resulting from absorption of the inertia torque by the friction engagement elements can be eliminated.
Furthermore, the output torque can decrease gently even after the absorption of the inertia torque.
Also, the decrease rate of the output torque, that is, a descending gradient of the output torque is kept constant every time a shift operation is performed. Therefore, the output torque can decrease gently even if a greater inertia torque is applied. In the case where the decrease rate of the output torque varies every time the shift operation is performed, a driver may feel uneasy. The invention is able to relieve the driver of such uneasiness resulting from the shift operation.
In addition, application of the torque assistance after the end of the shift operation can be prohibited during the shift operation at a low inertia torque, namely, when the shift shock is substantially negligible. Therefore, the motor generator does not have to output unnecessary torque, leading to power reduction.
Furthermore, it is possible to reduce the torque input to the automatic transmission by the amount of the inertia torque by means of a negative torque output from the motor generator, that is, torque-down control executed by the motor generator serving as the generator.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and further objects, features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings, wherein like numerals are used to represent like elements and wherein:
FIG. 1 is a block diagram showing a structure of a vehicle driving unit according to a first embodiment of the invention;
FIG. 2 is a flowchart showing a series of torque assistance control processes according to the first embodiment;
FIG. 3 is a timing chart representing a shift operation under the torque assistance control;
FIG. 4 is a beginning part of a flowchart showing a series of torque-down and torque-assistance control processes according to a second embodiment of the invention;
FIG. 5 is an ending part of the flowchart started in FIG. 4;
FIG. 6 is a timing chart representing a typical example of a shift operation under the torque-down and torque-assistance control; and
FIG. 7 is a timing chart of a generally employed hydraulic shift control process.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Preferred embodiments of the invention will be described referring to the drawings. FIG. 1 is a block diagram showing an entire structure of a vehicle driving unit according to a first embodiment of the invention. The driving unit includes an engine (E/G) 1, an automatic transmission 3 for transmitting motor power of the engine 1 to wheels (not shown), and a motor generator (M/G) 4 of a permanent magnet synchronous motor type functioning as a motor for driving the engine 1 and wheels via the automatic transmission 3 and functioning as a generator for recovering inverse driving energy from the engine 1 and the wheels. In the aforementioned driving unit, the engine 1, the motor generator 4, and the automatic transmission 3 are controlled by a control system 5(T/M&M/G-ECU).
In the vehicle driving unit, the automatic transmission 3 is connected to a driving source, that is, the engine 1 and the motor generator 4 via a power split device 2 functioning as a starting device. The power split device 2 is connected to the engine 1 via a forward clutch (CF) and is provided with a planetary gear unit 20 which is connected to the motor generator 4 and the automatic transmission 3. The planetary gear unit 20 has a simple construction including rotating elements such as a ring gear 21, a sun gear 22, and a carrier 24 of a pinion gear 23 which engages with the ring gear 21 and the sun gear 22. The ring gear 21 is connected to an output shaft 11 of the engine 1 via the forward clutch (CF), the sun gear 22 is connected to a rotor 41 of the motor generator 4 and the carrier 24 is connected to an input shaft 31 of the automatic transmission 3 respectively. A lock-up clutch (CD) for engaging/disengaging the ring gear 21 with/from the sun gear 22 is provided such that the planetary gear unit achieves locked-up rotation or planetary rotation.
The control system for controlling the above-described driving unit is mainly formed of an electronic control system (T/M&M/G-ECU) 5 which controls the motor generator 4 via an inverter 40 and controls friction engagement elements of the automatic transmission 3 via a hydraulic control device. The control system is further provided with a battery 6 for storing energy recovered by the motor generator 4 as electric power and supplying the power to drive the motor generator 4, the inverter 40 constituting control means of the motor generator 4, the hydraulic control device constituting control means of the automatic transmission 3, and an engine control computer (E/G-ECU) 7 for sending/receiving information to/from the electronic control system 5. Additionally, the control system includes, as information detection means for control operations, an input revolution sensor 81 for detecting an input revolution of the input shaft 31 of the automatic transmission 3, a vehicle speed sensor 82 serving as output revolution detection means for detecting a vehicle speed in accordance with a revolution of the output shaft 32 of the automatic transmission 3, and a neutral start switch (not shown) for detecting a shift position of the automatic transmission 3.
The vehicle driving unit constructed as described above enables it to select engagement or disengagement of the forward clutch (CF) and the lock-up clutch (CD) of the power split device 2 so as to realize various running states. These running states include a motor mode running state where only the motor generator 4 performs a driving operation, a split mode running state where the engine 1 mainly performs the driving operation but the motor generator 4 also performs the driving or braking operation partially, a parallel hybrid mode running state where both the engine 1 and the motor generator 4 perform the driving operation, an engine mode running state where only the engine 1 performs the driving operation, and a recovery mode running state where the motor generator 4 performs a dynamic braking operation.
The automatic transmission 3 with four speeds according to the first embodiment employs two planetary gears (P1, P2) as shift elements. The automatic transmission 3 is formed by combining a shift mechanism with a planetary gear (P0). The shift mechanism including three forward speeds and one reverse speed is controlled by engagement/disengagement of a plurality of clutches and brakes as friction engagement elements which are controlled according to the invention. The planetary gear (P0) constitutes an overdrive mechanism similarly controlled by engagement/disengagement of a plurality of clutches and brakes. In the planetary gear (P0), a carrier (Cr0) connected to the input shaft 31 of the transmission 3 and a sun gear (S0) are connected with each other via a clutch (C0) and a one-way clutch (F0) that are disposed in parallel. The sun gear (S0) can be arrested by a brake (B0). A ring gear (R0) constituting an output element of the planetary gear (P0) is connected to a ring gear (R1) of a planetary gear (P1) via a clutch (C1) and is connected to sun gears (S1, S2) via a clutch (C2). A sun gear (S2) and a ring gear (R2) of a planetary gear (P2) are respectively connected to the sun gear (S1) and a carrier (Cr1) of the planetary gear (P1). The ring gear (R2) constitutes the output element of the automatic transmission 3. The sun gears (S1, S2) can be arrested by a brake (B1) via a one-way clutch (F1) and a brake (B2) that are disposed in series. A carrier (Cr2) of the planetary gear (P2) can be arrested by a one-way clutch (F2) and a brake (B3) that are disposed in parallel.
The control system of the invention is provided with shift operation termination determination means for determining how much time remains until the shift operation is terminated (at step S6, which will be described later) and torque output command means (at step S10, which will also be described later) for generating a torque output command to the motor generator such that the output torque decreases gently from a predetermined torque value in response to a determination that the shift operation is about to terminate, as made by the shift operation termination determination means. These means are formed as control programs installed in the electronic control system 5. The control programs will be described referring to flowcharts and timing charts.
Referring to a flowchart of FIG. 2, first at step S1, it is determined whether or not a shift signal has been outputted, that is, a shift operation has been performed. If NO in step S1, the program invariably proceeds to step S11, where normal running control is executed by controlling outputs of the engine (E/G) or the motor generator (M/G) in accordance with a throttle opening.
If YES in step S1, the program proceeds to step S2 where input/output revolutions are read from an actual value of the transmission input revolution detected by the input revolution sensor 81 and an actual value of the transmission output revolution (Nout) detected by the vehicle speed sensor 82. Alternatively, it is possible to use the engine revolution that can be fetched from the engine control computer 7, which is substantially equal to the actual input revolution in the vehicle driving unit of the first embodiment. The revolution fetched from a resolver attached to the motor generator may also be used because the engine 1 and the motor generator 4 are locked up.
In the next step S3, it is determined whether or not the input revolution has changed with respect to the gear ratio and the output revolution. The start of the revolution change indicates that the friction engagement elements have entered an inertia phase. If YES in step S3, the program proceeds to step S4, where an amount of change (dN) in transmission (T/M) input revolution is calculated. In step S5, the time period (tes) remaining until the end of the revolution change is calculated based on the amount of change (dN) determined in step S4.
In step S6, it is determined whether or not the calculated time period (tes) remaining until the end of the revolution change is equal to or less than a predetermined time period (tmd). It is practically difficult to cause the motor generator to generate a torque immediately after the end of revolution change. This is because there is a certain delay of time taken for such a process as signal transmission between computers. Therefore, the aforementioned determination process step is necessary to prepare to generate the torque of the motor generator 4 just prior to the end of the shift operation (before expiration of (tmd)) in order to compensate for the delay.
In step S7, an inertia torque (Ti) is calculated using the following equation;
i=I×dN.
where I stands for a moment of inertia. In step S8, a torque assistance time (ta) is set in accordance with the calculated inertia torque (Ti). The torque assistance time (ta) is set such that the rate of a change in the output torque (gradient) is kept constant.
In step S9, it is determined whether or not the inertia torque (Ti) is equal to or more than a predetermined value (Ts). If NO in step S9, that is, if it is determined that the inertia torque (Ti) is smaller than the predetermined value (Ts), the shift shock is considered to be negligible. Therefore, the program is terminated without executing torque assistance control. If YES in step S9, that is, if it is determined that the torque assistance is required, the program proceeds to step S10. In step S10, a torque (Tm) output from the motor generator 4 is equalized to the inertia torque (Ti), i.e., (Ti=Tm). Concurrently, the output torque (Tm) of the motor generator 4 is decreased over time to zero within the torque assistance time (ta).
FIG. 3 is a timing chart for a upshift operation, which is a typical example of the torque assistance control as described above. Referring to the timing chart, at an initial stage, the transmission input revolution (Ne) assumes a high value corresponding to a lower gear stage prior to the shift operation. The value of the (Ne) gradually increases as the vehicle is accelerated. The value of the engagement hydraulic pressure assumes zero, indicating a disengagement state. The value of the output torque (Tout) gradually decreases as the vehicle is accelerated.
Referring back to FIG. 2, when step S1 determines that the shift signal has been outputted, the hydraulic control device outputs an engagement pressure applied to the friction engagement elements. The friction engagement elements enter an inertia phase due to the increase over time of the engagement hydraulic pressure level, thus transmitting the torque. Then, the transmission output torque (Tout) decreases and the input revolution (Ne) starts to change, which causes a shift state. Step S3 determines whether or not the input revolution has started to change. The revolution change is shown by a declining line in FIG. 3. Upon the beginning of the revolution change, the transmission output torque (Tout) increases sharply to reach a value greater than an input torque of an engine prior to declination by an amount of the generated inertia torque.
At this timing, the program starts to calculate an amount of change (dN) in transmission input revolution in step S4 and starts to calculate the time period (tes) remaining until the end of the revolution change in step S5.
When the shift state proceeds to reach the timing which is (tmd) prior to expiration of the time (tes) remaining until the end of the revolution change, the inertia torque (Ti) is calculated in step S7 and the assistance time (ta) is calculated in step S8 based on the determination made in step S6 whether or not little time is left before termination of the shift operation. A command for outputting the torque is generated in step S10. At the transmission side, the input revolution (Ne) is synchronized with the revolution at a gear stage after the upshift operation, which terminates the revolution change. Then, the inertia torque is quickly absorbed by the friction engagement elements. The transmission output torque (Tout) tends to decline to a lower output torque corresponding to a running load at the gear stage after the upshift operation as shown by a broken line of the timing chart of FIG. 3. As the assistance torque is output in accordance with the declination, the transmission output torque decreases gently at a descending gradient shown by a solid line of the timing chart. The descending gradient matches the decrease over time of the output torque of the motor generator performed in accordance with the assistance time (ta) calculated in step S8.
Referring to FIGS. 4 to 6, a second embodiment of the invention will be described. This embodiment is obtained by adding torque-down control to the torque assistance control of the first embodiment. In the second embodiment, as shown in flowcharts of FIGS. 4 and 5, steps S21 to S23 and steps S31 to S34 related to the torque assistance control are substantially the same as steps S1 to S3 and S7 to S10 of the flowchart of the first embodiment. Therefore, the explanation of those steps will be omitted. The torque-down control characteristic of the second embodiment will be described.
The program starts the torque-down control in step S24, where the motor generator functions as a generator to decrease the transmission input torque by a predetermined amount. The predetermined decrease amount of the torque is defined by the type of a shift operation and an engine revolution, which is stored in a memory as map data. In step S25, an amount of change (dN) in transmission (T/M) input revolution is calculated. In step S26, it is determined whether or not the calculated amount of change (dN) is equal to or less than an ideal amount of change in revolution (idN). In this case, the hydraulic pressure is set without executing the torque-down control. In accordance with the torque-down control executed in step S24, the shift operation is likely to be performed at a high rate. If NO in step S26, that is, if the shift operation is performed at an excessively high rate, the engagement pressure applied to the friction engagement elements decreases in step S27 so as to modify the rate of the shift operation to an ideal value. If YES in step S26, the engagement hydraulic pressure applied to the friction engagement elements is maintained in step S28.
Subsequently, in step S29, the time (tes) to elapse until the end of the revolution change is calculated based on the amount of change (dN) in the same manner as performed in the torque assistance control. In step S30, it is determined whether or not the time (tes) is equal to or less than a predetermined value of time (tde). Although the control process steps subsequent to step S30 are different from those of the first embodiment, the reason for executing the controlling is substantially the same as that of the first embodiment. It is practically difficult to switch the output of the motor generator from the down (negative) side to the up (positive) side simultaneously with the end of the revolution change. This is because there is a certain delay of time taken for such a process as signal transmission between computers. Therefore, the aforementioned determination process step is necessary to output the torque-down termination command prior to the end of the shift operation (before expiration of the time (tde)) in step S30-1 and to cause the motor generator to terminate the torque-down control. The following steps S31 to S34 relate to the torque assistance control, which are the same as steps S7 to S10 of the first embodiment.
FIG. 6 is a timing chart for an upshift operation, which is a typical example of the torque assistance control to which the torque-down control is added. The program starts to perform the control substantially in the same manner as in the first embodiment. Referring to FIG. 4, when it is determined that the shift signal has been outputted in step S21, the hydraulic control device outputs an engagement pressure applied to the friction engagement elements (not shown in the flowchart). The subsequent control process will be the same as that executed in the first embodiment. That is, the engagement hydraulic pressure is increased over time, the friction engagement elements enter an inertia phase and transmission of the torque is initiate&. The transmission output torque (Tout) declines and the input revolution (Ne) starts to change (as shown by a steep declining line of FIG. 6), leading to a shift state. Referring back to FIG. 4, step S23 determines the start of the revolution change. The program proceeds to step S24, where the motor generator 4 immediately starts outputting a negative (minus) torque. In response to the start of revolution change, the transmission output torque (Tout) sharply increases, reaching a value greater than the input engine torque prior to decline thereof by an amount of the inertia torque generated during the revolution change. The torque-down control is performed such that the transmission output torque decreases to a desired engine torque. Likewise, the engagement hydraulic pressure decreases in accordance with the decreased Tout. The descending gradient of the input revolution (Ne) becomes gentle as shown in FIG. 6, keeping an optimum shift time.
When the shift state reaches the time which is (tde) prior to expiration of the time period (tes) to elapse until the end of the shift operation, step S30-1 stops generating torque-down outputs based on the determination in step S30. The program proceeds to the torque assistance control. In this control process, the transmission output torque during the shift operation is reduced by executing the torque-down control and decreasing the engagement pressure. Therefore, the torque assistance amount to be supplied after the end of the shift operation decreases.
The invention employs the motor generator 4 to provide such assistance that the transmission output torque (Tout) does not decline after the end of revolution change. As a result, the transmission output torque (Tout) decreases gently. An inertia torque is derived from a rate of change in engine revolution during the shift operation. When the engine revolution has stopped changing, the motor generator 4 outputs the derived inertia torque. Then, the motor generator torque is decreased over time down to zero within a predetermined time period (ta). The predetermined time period (ta) for decreasing the motor generator torque over time is defined by the inertia torque.
While the invention has been described with reference to two preferred embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments or construction. To the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | In a vehicle driving unit employing a driving source formed by combining an engine with a motor generator, a control system prevents a sharp decline of an output torque of a transmission at the end of a shift operation without extending a time period required for the shift operation. The shift shock resulting from the sharp decline of the output torque can be eliminated. The vehicle driving unit is provided with an engine, a motor generator and a multi-stage automatic transmission for accomplishing a predetermined speed by engagement of friction engagement elements. The control system includes a shift operation termination determination step for determining the length of time remaining until the termination of a shift operation being performed by engagement of the friction engagement elements and a torque output command step for generating a torque assistance command to the motor generator based on the determination made during the shift operation termination determination step such that the transmission output torque decreases gently from a predetermined torque value. An assistance torque is outputted to prevent the sharp decline of the transmission output torque at the end of the shift operation caused by the inertia torque being rapidly absorbed by the friction engagement elements. | 1 |
[0001] The application claims the filing-date priority of Provisional Application No. 61/142,575, filed Jan. 5, 2009, the disclosure of which is incorporated herein in its entirety; the application also claims priority to U.S. patent application Ser. No. 12/139,391, filed Jun. 13, 2008, the disclosure of which is incorporated herein in its entirety; this application also claims priority to U.S. patent application Ser. No. 12/652,040, filed Jan. 5, 2010, the disclosure of which is incorporated herein in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The disclosure relates to a method and apparatus for efficient deposition of a patterned film on a substrate. More specifically, the disclosure relates to a method and apparatus for supporting and transporting a substrate on gas bearing during thermal jet printing of material on a substrate.
[0004] 2. Description of Related Art
[0005] The manufacture of organic light emitting devices (OLEDs) requires depositing one or more organic films on a substrate and coupling the top and bottom of the film stack to electrodes. The film thickness is a prime consideration. The total layer stack thickness is about 100 nm and each layer is optimally deposited uniformly with an accuracy of better than .+−.1 nm. Film purity is also important. Conventional apparatuses form the film stack using one of two methods: (1) thermal evaporation of organic material in a relative vacuum environment and subsequent condensation of the organic vapor on the substrate; or, (2) dissolution of organic material into a solvent, coating the substrate with the resulting solution, and subsequent removal of the solvent.
[0006] Another consideration in depositing the organic thin films of an OLED is placing the films precisely at the desired location on the substrate. There are two conventional technologies for performing this task, depending on the method of film deposition. For thermal evaporation, shadow masking is used to form OLED films of a desired configuration. Shadow masking techniques require placing a well-defined mask over a region of the substrate followed by depositing the film over the entire substrate area. Once deposition is complete, the shadow mask is removed. The regions exposed through the mask define the pattern of material deposited on the substrate. This process is inefficient as the entire substrate must be coated, even though only the regions exposed through the shadow mask require a film. Furthermore, the shadow mask becomes increasingly coated with each use, and must eventually be discarded or cleaned. Finally, the use of shadow masks over large areas is made difficult by the need to use very thin masks (to achieve small feature sizes) that make said masks structurally unstable. However, the vapor deposition technique yields OLED films with high uniformity and purity and excellent thickness control.
[0007] For solvent deposition, ink jet printing can be used to deposit patterns of OLED films. Ink jet printing requires dissolving organic material into a solvent that yields a printable ink. Furthermore, ink jet printing is conventionally limited to the use of single layer OLED film stacks, which typically have lower performance as compared to multilayer stacks. The single-layer limitation arises because printing typically causes destructive dissolution of any underlying organic layers. Finally, unless the substrate is first prepared to define the regions into which the ink is to be deposited, a step that increases the cost and complexity of the process, ink jet printing is limited to circular deposited areas with poor thickness uniformity as compared to vapor deposited films. The material quality is also lower due to structural changes in the material that occur during the drying process and due to material impurities present in the ink. However, the ink jet printing technique is capable of providing patterns of OLED films over very large areas with good material efficiency.
[0008] No conventional technique combines the large area patterning capabilities of ink jet printing with the high uniformity, purity, and thickness control achieved with vapor deposition for organic thin films. Because ink jet processed single layer OLED devices continue to have inadequate quality for widespread commercialization, and thermal evaporation remains impractical for scaling to large areas, it is a major technological challenge for the OLED industry to develop a technique that can offer both high film quality and cost-effective large area scalability.
[0009] Manufacturing OLED displays may also require the patterned deposition of thin films of metals, inorganic semiconductors, and/or inorganic insulators. Conventionally, vapor deposition and/or sputtering have been used to deposit these layers. Patterning is accomplished using prior substrate preparation (e.g., patterned coating with an insulator), shadow masking as described above, and when a fresh substrate or protective layers are employed, conventional photolithography. Each of these approaches is inefficient as compared to the direct deposition of the desired pattern, either because it wastes material or requires additional processing steps. Thus, for these materials as well there is a need for a method and apparatus for depositing high-quality, cost effective, large area scalable films.
[0010] Certain applications of thermal jet printing require non-oxidizing environment to prevent oxidation of the deposited materials or associated inks. In a conventional method, a sealed nitrogen tent is used to prevent oxidation. Conventional systems use a floating system to support and move the substrate. A floatation system can be defined as a bearing system of alternative gas bearings and vacuum ports. The gas bearings provide the lubricity and non-contacting support for the substrate, while the vacuum supports the counter-force necessary to strictly control the height at which the relatively light-weight substrate floats. Since high-purity nitrogen gas can be a costly component of the printing system, it is important to minimize nitrogen loss to the ambient.
[0011] Accordingly, there is a need for load-locked printing system which supports a substrate on gas bearings while minimizing system leakage and nitrogen loss.
SUMMARY
[0012] The disclosure relates to a method and apparatus for preventing oxidation or contamination during a thermal jet printing operation. The thermal jet printing operation may include OLED printing and the printing material may include suitable ink composition. In an exemplary embodiment, the printing process is conducted at a load-locked printer housing having one or more chambers. Each chamber is partitioned from the other chambers by physical gates or fluidic curtains. A controller coordinates transportation of a substrate through the system and purges the system by timely opening appropriate gates. The substrate may be transported using gas bearings which are formed using a plurality of vacuum and gas input portals. The controller may also provide a non-oxidizing environment within the chamber using a gas similar to, or different from, the gas used for the gas bearings. The controller may also control the printing operation by energizing the print-head at a time when the substrate is positioned substantially thereunder.
[0013] In one embodiment, the disclosure relates to a method for printing a film of OLED material on a substrate by (i) receiving the substrate at an inlet chamber; (ii) flooding the inlet load-locked chamber with a noble gas and sealing the inlet chamber; (iii) directing at least a portion of the substrate to a print-head chamber and discharging a quantity of OLED material from a thermal jet discharge nozzle onto the portion of the substrate; (iv) directing the substrate to an outlet chamber; (v) partitioning the print-head chamber from the outlet chamber; and (vi) unloading the print-head from the outlet chamber. In one embodiment of the invention, the print-head chamber pulsatingly delivers a quantity of material from a thermal jet discharge nozzle to the substrate.
[0014] In another embodiment, the disclosure relates to a method for depositing a material on a substrate. The method includes the steps of: (i) receiving the substrate at an inlet chamber; (ii) flooding the inlet chamber with a chamber gas and sealing the inlet chamber; (iii) directing at least a portion of the substrate to a print-head chamber and discharging a quantity of material from a thermal jet discharge nozzle onto the portion of the substrate; (iv) directing the substrate to an outlet chamber; (v) partitioning the print-head chamber from the outlet chamber; and (vi) unloading the print-head from the outlet chamber. The print-head chamber pulsatingly delivers a quantity of material from a thermal jet discharge nozzle to the substrate.
[0015] In another embodiment, the disclosure relates to a load-locked printing apparatus, comprising an inlet chamber for receiving a substrate, the inlet chamber having a first partition and a second partition; a print-head chamber in communication with the inlet chamber, the print-head chamber having a discharge nozzle for pulsatingly metering a quantity of ink onto a substrate, the second partition separating the print-head chamber from the inlet chamber; an outlet chamber in communication with the print-head chamber through a third partition, the outlet chamber receiving the substrate from print head chamber and exiting the substrate from a fourth chamber. In a preferred embodiment, the inlet chamber, the print-head chamber and the outlet chamber provide an inert gas environment while the discharge nozzle pulsatingly meters the quantity of ink onto the substrate. Although the implementation of the invention are not limited thereto, the inert gas environment can be a noble gas (e.g. argon, helium, nitrogen or hydrogen).
[0016] In still another embodiment, the disclosure relates to a load-locked thermal jet printing system. The system includes a housing with an inlet partition and an outlet partition. The housing defines a print-head chamber for depositing a quantity of ink onto a substrate. The housing also includes an inlet partition and an outlet partition for receiving and dispatching the substrate. A gas input provides a first gas to the housing. A controller communicates with the print-head chamber, the gas input and the inlet and outlet partitions. The controller comprises a processor circuit in communication with a memory circuit, the memory circuit instructing the processor circuit to (i) receive the substrate at the inlet partition; (ii) purge the housing with the first gas; (iii) direct the substrate to a discharge nozzle at the print-head chamber; (iv) energize the thermal jet discharge nozzle to pulsatingly deliver a quantity of film material from the discharge nozzle onto the substrate; and (v) dispatch the substrate from the housing through the outlet partition.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] These and other embodiments of the disclosure will be discussed with reference to the following exemplary and non-limiting illustrations, in which like elements are numbered similarly, and where:
[0018] FIG. 1 is a schematic representation of a conventional substrate floatation system;
[0019] FIG. 2 is a schematic representation of an exemplary load-locked printing housing;
[0020] FIG. 3 is a schematic representation of the load-locked printing housing of FIG. 2 receiving a substrate;
[0021] FIG. 4 schematically shows the substrate received at the print-head chamber of the housing;
[0022] FIG. 5 schematically shows the completion of the printing process of FIGS. 3 and 4 ;
[0023] FIG. 6 is a schematic representation of a print-head for use with the load-locked housing of FIG. 2 ; and
[0024] FIG. 7 is an exemplary load-locked system according to an embodiment of the invention;
[0025] FIG. 8 shows several types of substrate misalignment within the print system, and
[0026] FIG. 9 shows a substrate pattern including fiducials and initial locus of area viewed by a camera or other imaging devices.
DETAILED DESCRIPTION
[0027] FIG. 1 is a schematic representation of a conventional substrate floatation system. More specifically, FIG. 1 shows a portion of a flotation system in which substrate 100 is supported by air bearings. The air bearings are shown schematically as arrows entering and leaving between baffles 110 . The substrate floatation system of FIG. 1 is typically housed in a sealed chamber (not shown). The chamber includes multiple vacuum outlet ports and gas bearing inlet ports, which are typically arranged on a flat surface. Substrate 100 is lifted and kept off a hard surface by the pressure of a gas such as nitrogen. The flow out of the bearing volume is accomplished by means of multiple vacuum outlet ports. The floating height is typically a function of the gas pressure and flow. In principle, any gas can be utilized for such a substrate floatation system; however, in practice it is preferable to utilize a floatation gas that is inert to the materials that come into contact with the gas. As a result, it is conventional to use noble gases (e.g., nitrogen, argon, and helium) as they usually demonstrate sufficient inertness.
[0028] The floatation gas is an expensive component of the substrate floatation system. The cost is compounded when the printing system calls for substantially pure gas. Thus, it is desirable to minimize any gas loss to the environment.
[0029] FIG. 2 is a simplified representation of an exemplary load-locked printing housing according to one embodiment of the disclosure. Housing 200 is divided into three chambers, including inlet chamber 210 , print-head chamber 220 and outlet chamber 230 . As will be discussed, each chamber is separated from the rest of housing 200 through a gate or a partition. In one embodiment of the disclosure the gates or partitions substantially seal the chambers from the ambient environment and from the rest of housing 200 . In another embodiment of the disclosure (not shown), chamber 230 is not included in housing 200 , and chamber 210 is utilized as both an inlet and an outlet chamber.
[0030] FIG. 3 is a schematic representation of the load-locked printing housing of FIG. 2 receiving a substrate. During operation, substrate 350 is received at inlet chamber 310 through inlet gates 312 . Inlet gates 312 can comprise a variety of options, including single or multiple moving gates. The gates can also be complemented with an air curtain (not shown) for minimizing influx of ambient gases into inlet chamber 310 . Alternatively, the gates can be replaced with air curtains acting as a partition. Similar schemes can be deployed in all gates of the housing. Once substrate 350 is received at inlet chamber 310 , inlet gates 312 close. The substrate can then be detained at inlet chamber 310 . At this time, the inlet chamber can be optionally purged from any ambient gases and refilled with the desired chamber gas, which is conventionally selected to be the same as the floatation gas, e.g. pure nitrogen or other noble gases. During the purging process, print-head inlet gate 322 as well as inlet gate 312 remain closed. Print-head inlet gate 322 can define a physical or a gas curtain. Alternatively, print-head inlet gate 322 can define a physical gate similar to inlet gate 312 .
[0031] FIG. 4 schematically shows the substrate received at the print-head chamber of the housing. Air bearings can be used to transport substrate 450 from inlet chamber 410 through print-head inlet gate 422 and into print-chamber 420 . Print-head chamber 420 houses the thermal jet print-head, and optionally, the ink reservoir. The printing process occurs at print-head chamber 420 . In one implementation of the invention, once substrate 450 is received at print-head chamber 420 , print-head gates 422 and 424 are closed during the printing process. Print-head chamber can be optionally purged with a chamber gas (e.g., high purity nitrogen) for further purification of the printing environment. In another implementation, substrate 450 is printed while gates 422 and 424 remain open. During the printing operation, substrate 450 can be supported by air bearings. The substrate's location in relation to housing 400 can be controlled using a combination of air pressure and vacuum, such as those shown in FIG. 1 . In an alternative embodiment, the substrate is transported through housing 400 using a conveyer belt.
[0032] Once the printing process is complete, the substrate is transported to the outlet chamber as shown in FIG. 5 . Here, print-head gates 522 and 524 are closed to seal off outlet chamber 530 from the remainder of housing 500 . Outlet gate 532 is opened to eject substrate 550 as indicated by the arrow. The process shown in FIGS. 3-5 can be repeated to continuously print OLED materials on multiple substrates. Alternatively, gates 512 , 522 , 524 and 532 can be replaced with air curtains to provide for continuous and uninterrupted printing process. In another embodiment of the disclosure, once the printing process is complete, the substrate is transported back to the inlet chamber 310 through gate 322 , where gate 322 can be subsequently sealed off and gate 312 opened to eject the substrate. In this embodiment, inlet chamber 310 functions also as the outlet chamber, functionally replacing outlet chamber 530 .
[0033] The print-head chamber houses the print-head. In a preferred embodiment, the print-head comprises an ink chamber in fluid communication with nozzle. The ink chamber receives ink, comprising particles of the material to be deposited on the substrate dissolved or suspended in a carrier liquid, in substantially liquid form from a reservoir. The ink head chamber then meters a specified quantity of ink onto an upper face of a thermal jet discharge nozzle having a plurality of conduits such that upon delivery to the upper face, the ink flows into the conduits. The thermal jet discharge nozzle is activated such that the carrier liquid is removed leaving behind in the conduits the particles in substantially solid form. The thermal jet discharge nozzle is then further pulsatingly activated to deliver the quantity of material in substantially vapor form onto the substrate, where it condenses into substantially solid form.
[0034] FIG. 6 is a schematic representation of a thermal jet print-head for use with the load-locked housing of FIG. 2 . Print-head 600 includes ink chamber 615 which is surrounded by top structure 610 and energizing element 620 . Ink chamber 615 is in liquid communication with an ink reservoir (not shown). Energizing element 620 can comprise a piezoelectric element or a heater. Energizing element 620 is energized intermittently to dispense a metered quantity of ink, optionally in the form of a liquid droplet, on the top surface of the thermal jet discharge nozzle 640 .
[0035] Bottom structure 630 supports nozzle 640 through brackets 660 . Brackets 660 can include and integrated heating element. The heating element is capable of instantaneously heating thermal jet discharge nozzle 640 such that the ink carrier liquid evaporates from the conduits 650 . The heating element is further capable of instantaneously heating the thermal jet discharge nozzle 650 such that substantially solid particles in the discharge nozzle are delivered from the conduits in substantially vapor form onto the substrate, where they condense into substantially solid form.
[0036] Print-head 600 operates entirely within the print-head chamber 220 and housing 200 of FIG. 2 . Thus, for properly selected chamber and floatation gases (e.g. high purity nitrogen in most instances), the ink is not subject to oxidation during the deposition process. In addition, the load-locked housing can be configured to receive a transport gas, such as a noble gas, for carrying the material from the thermal jet discharge nozzle 640 onto the substrate surface. The transport gas may also transport the material from the thermal jet discharge nozzle 640 to the substrate by flowing through conduits 650 . In a preferred embodiment, multiple print-heads 600 are arranged within a load-locked print system as an array. The array can be configured to deposit material on a substrate by activating the print-heads simultaneously or sequentially.
[0037] FIG. 7 is an exemplary load-locked system according to an embodiment of the invention. Load-locked system of FIG. 7 includes a housing with inlet chamber 710 , print-head chamber 720 and outlet chamber 730 . Inlet chamber 710 communicates through gates 712 and 722 . Print-head chamber 720 receives substrate 750 from the inlet chamber and deposits organic LED material thereon as described in relation to FIG. 6 . Gate 724 communicates substrate 750 to outlet chamber 730 after the printing process is completed. The substrate exists outlet chamber 730 through gate 732 .
[0038] Vacuum and pressure can be used to transport substrate 750 through the load-locked system of FIG. 7 . To control transporting the substrate, controller 770 communicates with nitrogen source 762 and vacuum 760 through valves 772 and 774 , respectively. Controller 770 comprises one or more processor circuits (not shown) in communication with one or more memory circuit (not shown). The controller also communicates with the load-locked housing and ultimately with the print nozzle. In this manner, controller 770 can coordinate opening and closing gates 712 , 722 , 724 and 732 . Controller 770 can also control ink dispensing by activating the piezoelectric element and/or the heater (see FIG. 6 ). The substrate can be transported through the load-locked print system through air bearings or by a physical conveyer under the control of the controller.
[0039] In an exemplary operation, a memory circuit (not shown) of controller 770 provides instructions to a processor circuit (not shown) to: (i) receive the substrate at the inlet partition; (ii) purge the housing with the first gas; (iii) direct the substrate to a discharge nozzle at the print-head chamber; (iv) energize the discharge nozzle to pulsatingly deliver a quantity of material from the thermal jet discharge nozzle onto the substrate; and (v) dispatch the substrate from the housing through the outlet partition. The first gas and the second gas can be different or identical gases. The first and/or the second gas can be selected from the group comprising nitrogen, argon, and helium.
[0040] Controller 770 may also identify the location of the substrate through the load-locked print system and dispense ink from the print-head only when the substrate is at a precise location relative to the print-head.
[0041] Another aspect of the invention relates to registering the substrate relative to the print-head. Printing registration is defined as the alignment and the size of one printing process with respect to the previous printing processes performed on the same substrate. In order to achieve appropriate registration, the print-head and the substrate need to be aligned substantially identically in each printing step. In one implementation of the invention, the substrate is provided with horizontal motion (i.e., motion in the x direction) and the print-head is provided with another horizontal motion (i.e., motion in the y direction). The x and y directions may be orthogonal to each other. With this arrangement, the movement of the print-head with respect to the substrate can be defined with a combination of these two horizontal directions.
[0042] When the substrate is loaded onto a load-locked system, the areas to be printed are usually not perfectly aligned in the x and y directions of the system. Thus, there is a need for detecting the misalignment, determining the required corrections to the motion of the print-head relative to the substrate and applying the corrections.
[0043] According to one embodiment of the invention, the pattern or the previous printing is detected using a pattern recognition system. This pattern can be inherent in the previous printing or may have been added deliberately (i.e., fiducials) for the pattern recognition step. By means of its recognition of the pattern, the misalignment of the substrate to the printing system's motion, direction or axis can be determined. This manifests itself as a magnification misalignment, a translational misalignment and an angular misalignment.
[0044] FIG. 8 shows several types of substrate misalignment within the print system, including translational misalignment, rotational misalignment, magnification misalignment and combinational misalignment. For each print-head scan motion relative to the substrate, the pattern recognition system will look for and find/recognize the desired pattern. The pattern recognition system can optionally be integrated with the controller (see FIG. 7 ). The pattern recognition system will look for and find/recognize the desired pattern. The pattern recognition system will provide the degree of error/misalignment in the x and y directions to the system's controller, which will then reposition the print-head and substrate to eliminate the error/misalignment. This means that for several motions of the print-head with respect to the substrate, the motion control system will check for misalignment and make the necessary corrections.
[0045] Alternatively, an initial scan of the entire substrate can be performed by the pattern recognition system utilizing the x and y motions available in the printing system. FIG. 9 shows a substrate pattern including fiducials and initial locus of area viewed by a camera or other imaging devices. In FIG. 9 , fiducials or alignment targets are identified as boxes 910 in each replicated “pixel.” Each pixel in this example, and in many OLED applications, comprises three sub-pixels each having a distinct color: red, green, and blue (RGB). The camera or the pattern recognition device initially focuses on an area of the substrate identified by circle 930 . Once the amount of misalignment is determined, the motion control system can compensate for the misalignment by causing the x and the y directions to move in a rotated and translated set of axes x 1 and y 1 such that these axis are a linear combination of the previous motions.
[0046] For either alignment technique, the printing control system will then cause the print-head to fire appropriately at the desired print axis as it scans the substrate. In the case of the embodiment described above, the print system will periodically use the pattern recognition system to update and adjust for any misalignment, causing the print-head to fire after alignment has been achieved. Depending on the degree of misalignment, the required update and adjustment steps may have to be repeated more often during the printing operations. Alternatively, the pattern recognition system must scan the substrate initially to assess the amount and direction of misalignment, then printing control system will utilize the misalignment information to adjust the print-head firing accordingly.
[0047] While the principles of the disclosure have been illustrated in relation to the exemplary embodiments shown herein, the principles of the disclosure are not limited thereto and include any modification, variation or permutation thereof. For example, while the exemplary embodiments are discussed in relation to a thermal jet discharge nozzle, the disclosed principles can be implemented with different type of nozzles. Moreover, the same or different gases can be used for floating the substrate and for providing a non-oxidizing environment within the chamber. These gases need not be noble gases. Finally, the substrate may enter the system from any direction and the schematic of a tri-chamber system is entirely exemplary. | The disclosure relates to a method and apparatus for preventing oxidation or contamination during a circuit printing operation. The circuit printing operation can be directed to OLED-type printing. In an exemplary embodiment, the printing process is conducted at a load-locked printer housing having one or more of chambers. Each chamber is partitioned from the other chambers by physical gates or fluidic curtains. A controller coordinates transportation of a substrate through the system and purges the system by timely opening appropriate gates. The controller may also control the printing operation by energizing the print-head at a time when the substrate is positioned substantially thereunder. | 1 |
This is a continuation of application Ser. No. 07/833,600 filed on Feb. 10, 1992, now abandoned which is a continuation of application Ser. No. 07/387,909 filed on Jul. 31, 1989, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a support for a natural human heart which may be used for the surgical correction of a deformed heart valve, specifically a heart valve which has become dilated. In particular, the present invention relates to a holder and flexible annuloplasty ring prosthesis combination for properly positioning the ring about the valve annulus during implantation.
The human heart generally includes four valves. Of these valves the more critical ones are known as the mitral valve, which is located in the left atrioventricular opening, and the tricuspid valve, which is located in the right atrioventricular opening. Both of these valves are intended to prevent regurgitation of blood from the ventricle into the atrium when the ventricle contracts. In preventing blood regurgitation both valves must be able to withstand considerable back pressure as the ventricle contracts. The valve cusps are anchored to the muscular wall of the heart by delicate but strong fibrous cords in order to support the cusps during ventricular contraction. Furthermore, the geometry of the heart valves ensure that the cusps overlay each other to assist in control ling the regurgitation of the blood during ventricular contraction.
Diseases and certain natural defects to heart valves can impair the functioning of the cusps in preventing regurgitation. For example, certain diseases cause the dilation of the heart valve annulus. Dilation may also cause deformation of the valve geometry or shape displacing one or more of the valve cusps from the center of the valve. Other diseases or natural heart valve defects result in deformation of the valve annulus with little or no dilation.
Dilation and/or deformation result in the displacement of the cusps away from the center of the valve. This results in an ineffective closure of the valve during ventricular contraction, which results in the regurgitation or leakage of blood during ventricle contraction. For example, diseases such as rheumatic fever or bacterial inflammations of the heart tissue can cause distortion or dilation of the valvular annulus. Other diseases or malformations result in the distortion of the cusps, which will also lead to ineffective closure of the valve.
One method of repairing an impaired valve is to completely replace the valve. This method is particularly suitable for replacing a heart valve when one of the cusps has been severely damaged or deformed. While the replacement of the entire valve eliminates the immediate problem associated with a dilated valve annulus, presently available heart valves do not possess the same durability as natural heart valves. Various surgical procedures have been developed to correct the deformation of the valve annulus and retain the intact natural heart valve.
These surgical techniques involve repairing the shape of the dilated or elongated valve. Such techniques, generally Known as annuloplasty, require surgically restricting the valve annulus to minimize dilation. Typically, a prosthesis is sutured about the base of the valve leaflets to reshape the valve annulus and restrict the movement of the valve annulus during the opening and closing of the valve.
A suitable prosthesis should allow the surgeon to properly reconstruct the heart valve annulus and minimize dilation, while allowing natural movement of the valve annulus during the opening and closing of the valve. The ability of the prosthesis to allow for a natural opening and closing of the valve is particularly important since such prostheses are not normally removed from the heart valve, even if the valve annulus heals to a normal geometry.
Many different types of prostheses have been developed for use in annuloplasty surgery. In general prostheses are annular or partially annular shaped members which fit about the base of the valve annulus. Initially the prostheses were designed as rigid frame members, to correct the dilation and reshape the valve annulus to the natural state. These annular prostheses were formed from a metallic or other rigid material, which flexes little, if at all, during the normal opening and closing of the valve.
Examples of rigid annuloplasty ring prostheses are disclosed in U.S. Pat. Nos. 3,656,185, issued to Carpentier on Apr. 18, 1972; and 4,164,046, issued to Cooley on Aug. 14, 1979. Certain artificial heart valves have also been developed with rigid frame members similar to the rigidity of the described valve prosthesis. Examples of this type of heart valve are disclosed in U.S. Pat. Nos. 4,204,283, issued to Bellhouse et al on May 27, 1980; and 4,306,319, issued to Kaster on Dec. 22, 1981.
Rigid annuloplasty ring prostheses adequately promote the healing of the valve annulus by restricting valve dilation and reshaping the valve annulus. However, this rigidity prevents the normal flexibility of the valve annulus. That is, a normal heart valve annulus continuously flexes during the cardiac cycle, and a rigid ring prosthesis interferes with this movement. Since the prosthesis remains implanted, even after the valve annulus has healed, a prosthesis of high rigidity will permanently restrict the normal opening and closing of the valve, and thus impair the normal functioning of the valve. Another disadvantage with a highly rigid ring prosthesis is the tendency of the sutures tearing during the normal movement of the valve annulus.
Other workers have suggested the use of completely flexible annuloplasty ring prostheses. Flexible prostheses include an inner support member formed from a flexible material. This support member is wrapped in woven, biocompatible cloth material. Resistance to the dilation of the annulus during the opening and closing of the valve is obtained by the proper suturing of the ring about the valve annulus.
One disadvantage with completely flexible ring prostheses is that during the implantation process the material forming the ring may become bunched at localized areas. This bunching of the prosthesis results in the phenomenon known as multiple plications of the ring prosthesis. One result of this phenomenon is variability of the ability of the ring to control the shape of the valve annulus. The bunched up areas of the ring tend to provide a more rigid area in comparison to the other portions of the ring which results in distorting the valve annulus during the opening and closing of the valve.
Examples of completely flexible ring prostheses are disclosed in U.S. Pat. No. 4,290,151, issued to Massana on Sep. 22, 1981, and are discussed In the articles of Carlos D. Duran and Jose Luis M. Ubago, "Clinical and Hemodymanic Performance of a Totally Flexible Prosthetic Ring for Atrioventricular Valve Reconstruction", 5 Annals of Thoracic Surgery, (No. 5), 458-463, (Nov. 1976) and M. Puig Massana et al, "Conservative Surgery of the Mitral Valve Annuloplasty on a New Adjustable Ring", Cardiovascular Surgery 1980, 30-37, (1981).
Still further types of annuloplasty ring prostheses are designed to allow for adjustment of the ring circumference, either during the surgical implantation, or as the ring prosthesis during the opening and closing of the valve. This type of adjustable prosthesis is typically designed in combination with a rigid, or at least partially rigid frame member.
An example of a self adjusting ring prosthesis is taught in U.S. Pat. No. 4,489,446, issued to Reed on Dec. 25, 1984. This annuloplasty ring prosthesis provides for self adjustment of the prosthesis annulus by two reciprocating pieces which form the prosthesis frame. The basic disadvantage of this ring prosthesis is that the individual frame members are formed from a rigid material, with the resulting prosthesis suffering the same disadvantages discussed above for rigid ring prosthesis in general.
Other examples of adjustable ring prostheses are taught in U.S. Pat. Nos. 4,602,911, issued to Ahmadi et al and 4,042,979, issued to Angell on Aug. 23, 1977, provide for mechanism of adjusting the ring circumference. In Ahmadi et al the ring prosthesis frame is a coiled spring ribbon which is adjusted by a mechanical screw assembly. In Angell, a drawstring is used to adjust the circumference of a rigid frame member. Again, these ring prostheses suffer from the disadvantages of the rigid ring prosthesis discussed above. The Angell prosthesis could also possess a substantially flexible portion after suturing which could include multiple plications for the reasons discussed above for the completely flexible prosthesis.
U.S. Pat. No. 4,055,861, issued to Carpentier on Nov. 1, 1977 teaches an annuloplasty ring prosthesis which has a flexibility between the completely flexible rings discussed above and rigid ring. The ring of Carpentier is deformable to an equal degree and simultaneously in all directions. The preferred support is described as having the elasticity of an annular bundle of 2 to 8 turns of a cylindrical bristle of poly(ethylene terephthalate).
While rigid and semi-rigid annuloplasty rings provide a benefit over flexible rings, the restrictive nature of such rings may be detrimental to the ability of the valve to normally open and close. It thus remains an object to provide a flexible annuloplasty ring which does not have the any of the above described detriments.
DESCRIPTION OF THE DRAWINGS
The present invention may be better understood and the advantages will become apparent to those skilled in the art by reference to the accompanying drawings, wherein like reference numerals refer to like elements in the several figures, and wherein:
FIG. 1 is a prospective exploded view of a annuloplasty ring prosthesis and holder assembly in accordance with an embodiment of the invention;
FIG. 2 is an exploded view of the ring mount portion and lower part of the handle portion of the holder assembly of FIG. 1;
FIG. 3 is a prospective view of the assembled ring mount and lower handle portions seen in FIG. 2;
FIG. 4 is a cross sectional view of the assembled ring mount and lower handle portions of FIG. 3 along line 4--4;
FIG. 5 is a top view of the ring mount seen in FIGS. 2-4 with a flexible annuloplasty secured thereto; and
FIG. 6 is a prospective view of a ring mount in accordance with another embodiment of the invention.
SUMMARY OF THE INVENTION
The present invention overcomes the above discussed disadvantages by providing an assembly for holding a substantially flexible annuloplasty ring in a substantially taut position for suturing about a valve annulus. The assembly includes a portion which is formed with a surface against which the annuloplasty ring is positioned and held in a shape substantially equivalent to at least a portion of the valve annulus. The assembly further includes a mechanism for releasably binding the annuloplasty ring this surface.
The annuloplasty ring prosthesis used with the assembly of the invention is a generally elongated flexible body element formed from an internal flexible frame wrapped in a woven cloth material.
The holder assembly includes a body which is formed with an outwardly facing surface against which is positioned the annuloplasty ring. This surface is dimensioned with a shape substantially similar to at least a portion of valve annulus. Preferably, this surface is formed with at least one depression for receiving a portion of the ring prosthesis.
The annuloplasty ring prosthesis is releasably retained against the body surface by at least a first thread. This thread is affixed at both ends to the body with a portion thereof passing at least partially through the annuloplasty ring prosthesis. The thread is affixed to the body to expose a portion which when disected subdivides the thread into two pieces affixed at one end to the body. At least one of these pieces defines that portion passing through the ring prosthesis and which is freely withdrawn from the annuloplasty ring.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is directed to a holder assembly for holding a substantially flexible annuloplasty ring in a substantially taut position for suturing about a valve annulus. The prosthesis of the invention is formed from a flexible body about which a woven cloth is wrapped to form a covering. The annuloplasty ring prosthesis of the invention is surgically sutured, with the aid of the holder assembly, to the annulus of a dilated and/or deformed heart valve. The dilation and/or deformation of heart valves may be the result of a disease, natural defect or physical damage to the valve annulus. This dilated and/or deformed heart valve will not completely close, allowing for regurgitation of blood with a closed valve.
The suturing of the prosthesis to the valve annulus restricts the circumference of the dilated valve to a more natural dimension. The prosthesis of the invention thus restrains dilation of the valve and al lows the surgeon to reshape the valve.
The holder assembly includes a ring mount assembly about which the annuloplasty ring is mounted and releasably affixed. Generally the ring mount assembly includes a ring support which formed with a shape similar to that of the valve annulus about which the annuloplasty ring is to be implanted. The annuloplasty ring is mounted about a portion of this ring support, typically about a curved portion. The holder assembly allows the surgeon to properly position the annuloplasty ring during the suturing process, and minimize the potential of forming multiple plications as the ring prosthesis is sutured in position.
Referring now to FIG. 1, an exploded view of a holder assembly to which an annuloplasty ring is mounted, as seen generally at 12 and 10 respectively. The holder assembly 12 includes a ring mount assembly 18 and handle assembly 40, which is formed from a handle 42 and housing 44.
The annuloplasty ring prosthesis 10 is a generally straight member formed with an inner frame 14 about which is wrapped an outer cloth 16, as better seen in FIGS. 4 and 5. Frame 14 is formed from a flat or tubular piece of resilient, flexible material, e.g. mylar, with the outer cloth 16 formed from any biocompatible, woven cloth material is adequate for use as the outer cloth 16. Preferably, the outer cloth 16 is dacron. This outer cloth 16 is tightly wrapped and sewen about this frame 14 The thickness of the outer cloth 16 is sufficient to allow the surgeon to pass a suture therethrough.
As seen in FIGS. 2 through 5, the ring prosthesis 10 is mounted about the lower portion of the holder assembly 12. This portion of the holder assembly 12 is the ring mount assembly 18. Ring mount assembly 18 includes a ring support 20. This ring support 20 is generally annular, with a shape similar to that of the annulus of the valve to which the ring prosthesis 10 is being sutured. More particularly, ring support 20 has a C-shaped portion 28, with its ends connected by a straight side 30.
The ring prosthesis 10 is fitted about the curved C-shaped portion 28 of the ring support 20. The ring support 20 is formed with a groove or trough 32 which is dimensioned to receive a portion of the ring prosthesis 10, as best seen in FIG. 4. The positioning of the ring prosthesis 10 within the trough 32 slightly deforms the ring prosthesis 10. This deformation places a thicker portion of the woven cloth 16 outside of the trough 32 to allow the surgeon to pass a suture therethrough.
The ring mount assembly 18 also includes a central support hub 22 to which the ring support 20 is attached by three integrally formed spokes, one of which is seen at 24. The arrangement allows the surgeon to visual observe the heart valve during the suturing process. Central support hub 22 is formed with an annular groove 36. This groove 36 is formed proximate that end 34 of hub 22 opposite ring support 20, and defines a post member 38. That portion of hub 22 remaining at that side of the groove 36 opposite the ring support 20, hub end 34, includes an inwardly tapering peripheral surface, as seen generally at 35. The hub 22 is also includes an open bore 37 through which is fitted a cylindrical plug 39. The plug 39 is dimensioned to extend out from both sides of the bore 37. The purpose of tapered surface 35, and the plug 39 will be described in greater detail herein.
As stated the handle assembly 40 includes an elongated post 42 and a housing 44. As seen in FIG. 1, housing 44 is mounted to an end 54 of post 42. While the housing 44 may be integrally formed at the end 54 of the post 42, preferably end 54 is formed with outwardly facing threads. These threads are formed to threadably mate with threads formed along a surface of an opening formed on the top of the housing 44, seen generally at 59. The opposite end of the post 42 Is formed with an external etched surface 52. This etched surface 52 assists the surgeon in gripping post 42.
Housing 44 Is a thimble shaped structure having a circular wall 60 which defines a cavity 46. As seen better in FIG. 4, cavity 46 is open at one side, seen generally as opening 45. The inner surface of the circular wall 60 inwardly converges a short distance from the opening 45. The cavity 46 is generally wide enough at the open side 45 to snuggly receive hub 22, but the plug 39 extends sufficiently outward from hub 22 to prevent passage through open side 45 into cavity 46. Hall 60 is formed with two J-shaped notches, seen at 48 and 49 in FIGS. 2 and 3. These J-shaped notches 48 and 49 are formed and positioned to respectively receive the ends of the plug 39 extending outward from the hub 22. The shape of the notches 48 and 49 defines a landing 50 between the long and short legs of each notche.
Handle assembly 40 is coupled to the ring mount assembly 18 by inserting end 54 of the hub 22 into the cavity 46, with the outwardly extending ends of the plug 39 passing through a respective on of each J-shaped notche 48 and 49. The tapered surface 35 of the hub 22 engages the inwardly tapering surface of the wall 60. This causes a slight compression of the hub end 34, resulting in a spring force. The spring force acts to restrain the movement of the outwardly extending ends of the plug 39 through the larger legs of the J-shaped notches 48 and 49. Additional exertion moves the plug 39 ends through the larger legs of J-shaped notches 48 and 49, with rotation of the handle 40 passing the outward ends of the plug 39 across the landings 50 and into the smaller leg of each J-shaped notch 48 and 49.
The spring force established by the slight compression of the hub end 54 maintains the assembly of the housing 44 and ring mount assembly 18. The handle 40 is decoupled from the ring mount assembly 18 by reversing the described procedure.
The mechanism for attaching the ring prosthesis 10 to the ring support 20 of the ring mount assembly 18 is seen in FIG. 5. Ring support 20 is formed with two holes 66 and 68. Each of the holes 66 and 68 is formed through the ring support 20 and communicates with the groove 32. The exact positioning of the holes 66 and 68 is not critical. As illustrated these holes 66 and 68 are formed along the straight portion of the ring support 20, at a location proximate two of the spokes 24.
One end 71 of a cord or suture 70 is passed through one of the holes, as illustrated hole 66, and tied off on the ring support 20. The other end 73 of suture 70 is passed through the body of ring prosthesis 10 from one end to the other. This end 73 is then passed first through hole 68 and then through and tied off at hole 66. After the ring prosthesis 10 is sutured in position about the valve annulus, that portion of the suture 70 between the two holes 66 and 68 is sniped. The suture 70 passes out of the ring prosthesis 10 by withdrawing the handle assembly 12.
In accordance with another embodiment, the first end 71 is tied off at hole 66, with the second end 73 passed first through one end of the ring prosthesis 10, and then brought back across and passed through the other prosthesis 10 end. This suture end 73 is again tied off at hole 66. Removal of suture 70 is accomplished by sniping the suture between the two holes.
The above described ring mount assembly 18 includes a ring support 20 formed by a C-shaped and straight side as best seen in FIG. 5. A second embodiment is seen in FIG. 6. This ring mount assembly 80 includes a ring support 82 which is formed with only an open C-shaped side 84. Except for the stated difference in shape of the ring support 82, this ring mount assembly 80 includes similar elements as those described for ring support 20, which are indicated by the prime of the previously provided element number, and will not be described in any more detail herein. This embodiment of ring mount assembly 80 provides an open area across which a suture is positioned after being tied off at the respective hole 66.
While the preferred embodiments have been described, various modifications and substitutions may be made thereto without departing from the scope of the invention. Accordingly, it is to be understood that the invention has been described by way of illustration and not limitation. | An assembly for holding a substantially flexible annuloplasty ring in a substantially taunt position for suturing about a valve annulus. The assembly includes a portion which is formed with a surface against which the annuloplasty ring is positioned and held in a shape substantially equivalent to at least a portion of the valve annulus. The assembly further includes a mechanism for releasably binding the annuloplasty ring to this surface. | 0 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to articles created and/or decorated using particulate from recycled souvenirs and a method of manufacture thereof. More particularly, the invention relates to a method of making and/or decorating articles such as garments with ground particulate obtained from noteworthy spectator sport objects such as race car tires, for example.
[0002] Many people attending, watching or who are otherwise fans of spectator sports commonly purchase merchandise having a design and/or indicia connected to the event and/or team and/or individual sport participant. Such items may include t-shirts, sweatshirts, shorts, pants, hats, jackets, mugs, glasses, coozies, etc., where the design and/or indicia are printed thereon. Many of these people also desire to obtain an actual article used in the event by the team or individual participant, e.g., a puck used in a game, although the opportunity to acquire these articles by chance (e.g., catching a puck in the stands) is of course very rare. Such items may sometimes be bought as a collectible but are typically expensive due to their direct connection to the event and/or sports participant. In some spectator sports such as auto racing, there are very few opportunities to acquire such articles actually used in a race.
[0003] It would therefore be desirable to provide merchandise articles for fans of a spectator sport which is made using an item used by the team or individual sports participant. It would furthermore be desirable to repurpose and recycle used sports items in the manufacturing of such merchandise and thereby have a positive impact on the environment.
SUMMARY OF THE INVENTION
[0004] The present invention addresses the above needs by providing an article with an applied recycled souvenir and a method of manufacturing the article with applied recycled souvenir. An item used in a spectator sport is considered to have souvenir value and is recycled by converting (e.g., by grinding) it into a particulate. The particulate (comprised of many individual granular particles) may be formed of a predetermined size and shape; e.g., with a particle size of between about 0.1 and 1500 microns, more preferably with a particle size of between about 0.5 and 800 microns and most preferably with a particle size of between about 1 and 400 microns. If desired, the original nature of the souvenir may be further emphasized or exaggerated by using even larger particle sizes to augment the visual and tactile characteristic of the design on the article. The particulate may also be a combination of granular sizes to obtain the desired visual and tactile effect. When the souvenir is a tire, for example, the particulate may be formed into a mixture of various sized particles such that when applied to the article, the particulate layer forms a raised surface that has peaks and valleys which are visually and tactically very evident. The larger particles (e.g., up to 1 mm or more in size) create actual “chunks” of the tire which provides an immediate indication of the nature of the actual souvenir.
[0005] The particles may be formed into random particle shapes or specific particle shapes (e.g., spherical, oblong, squared, etc. or any combination thereof). The particles may be deposited on the article in a specific or nonspecific (i.e., random) laydown pattern according to particle shape and/or size. The term “laydown pattern” as used herein means the pattern the individual particles make within the outline of the overall recycled souvenir design pattern. An article such as a garment (e.g., t-shirt) is decorated with the recycled souvenir particles, wherein in a first embodiment, the method comprises the steps of:
a) converting (e.g., by grinding) at least a portion of said souvenir into a particulate; b) screen printing a colored ink layer onto the article in a desired recycled souvenir design pattern (which may be a representation of the nature of the recycled souvenir (e.g., if the souvenir is a hockey puck, the pattern may be designed to look like a hockey puck)); c) screen printing a first coat liquid adhesive layer onto the colored ink layer in said desired souvenir pattern; d) distributing the particulate in a laydown pattern onto said liquid adhesive layer; e) removing excess particulate from the article not located on the liquid adhesive layer (e.g., by vacuum pick-up); f) drying (e.g., flash drying) the first coat liquid adhesive layer and thereby bonding the particulate to the first coat liquid adhesive layer to form a first bonded layer at a preferred drying temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; g) screen printing a second coat liquid adhesive layer onto the first bonded layer and thereby forming a multilayer composite; h) if necessary, curing the multilayer composite (e.g., via conveyor oven at a preferred curing temperature of approximately 350 Fahrenheit for a preferred duration of between about 30 and 35 seconds); and i) if necessary, heat pressing the multilayer composite at a preferred temperature of approximately 375 degrees Fahrenheit for a preferred duration of between about 15 and 18 seconds.
[0015] The drying and curing steps may vary depending in the types of inks used, some of which may be quick drying at room temperature thereby negating the need for a separate drying/cure step. The colored ink layer may be any suitable screen printing ink (e.g., plastisol) and the adhesive layer may be any suitable material which will bind with the souvenir particulate. The adhesive layer may be a screen printing glue or may be a screen printing clear ink (e.g., clear plastisol which has been found to be an adequate particulate binder). It is noted that final step i) is process dependent, i.e., this step may only be necessary when decorating certain types of article such as t-shirts, for example. It is furthermore understood that the steps may be combined and/or performed in a different order. For example, in a second alternate embodiment the colored ink and first adhesive layer are combined together prior to depositing the mixture on the article, the alternate method comprises the steps of:
a) converting (e.g., by grinding) at least a portion of said souvenir into a particulate; b) mixing colored ink and a liquid adhesive together to form a homogeneous base mixture; c) screen printing the homogenous base mixture onto the article in a desired pattern (which may be a representation of the nature of the recycled souvenir (e.g., if the souvenir is a hockey puck, the pattern may be designed to look like a hockey puck)); d) distributing the particulate onto said homogenous base mixture; e) removing excess particulate from the article not located on the ink and liquid adhesive layer (e.g., by vacuum pick-up); f) drying (e.g., flash drying) the homogenous base mixture with the particulate thereon to form a first bonded layer at a preferred drying temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; g) screen printing a second coat liquid adhesive layer onto the first bonded layer and thereby forming a multilayer composite; h) if necessary, curing the multilayer composite (e.g., via conveyor oven at a preferred curing temperature of approximately 350 Fahrenheit for a preferred duration of between about 30 and 35 seconds; and i) if necessary, heat pressing the multilayer composite together at a preferred temperature of approximately 375 degrees Fahrenheit for a preferred duration of between about 15 and 18 seconds.
[0025] As with the first embodiment, it is noted that final step i) is process dependent, i.e., this step may only be necessary when decorating certain types of articles such as t-shirts, for example. It is furthermore understood that the steps may be combined and/or performed in a different order. As stated above, the drying and curing steps may vary depending in the types of inks used, some of which may be quick drying at room temperature thereby negating the need for a separate drying/cure step and/or heat/press source.
[0026] In yet another embodiment, a method of decorating an article with a recycled souvenir comprises the steps of:
a) converting at least a portion of said souvenir into a particulate; b) providing an adhesive backing layer on a non-binding release paper; c) screen printing a colored ink layer onto the adhesive backing layer in a desired pattern; d) screen printing a first coat liquid adhesive layer over the colored ink layer; e) distributing the particulate onto said first coat liquid adhesive layer; f) removing excess particulate from the article not located or bonded on the liquid adhesive layer; g) drying (e.g., flash drying) the first coat liquid adhesive layer with the particulate thereon to form a first bonded layer at a preferred temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; h) screen printing a second coat liquid adhesive layer onto the first bonded layer and thereby forming a multilayer composite; i) if necessary, curing the multilayer composite at a preferred curing temperature of approximately 350 Fahrenheit for a preferred duration of between about 30 and 35 seconds; and j) if necessary, heat pressing the multilayer composite at a temperature of approximately 375 degrees Fahrenheit for between about 15 and 18 seconds to thereby form the design pattern as a decal; and k) removing the decal from the release paper and applying the decal to an article.
[0038] In yet a further embodiment, a method of decorating an article with a recycled souvenir comprises the steps of:
a) converting at least a portion of said souvenir into a particulate; b) screen printing a colored ink layer onto a patch of material in a desired pattern; c) screen printing a first coat liquid adhesive layer over the colored ink layer; d) distributing the particulate onto said liquid adhesive layer; e) removing excess particulate from the article not located or bonded on the liquid adhesive layer; f) drying (e.g., flash drying) the first coat liquid adhesive layer with the particulate thereon to form a first bonded layer at a preferred temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; g) screen printing a second coat liquid adhesive layer onto the first bonded layer and thereby forming a multilayer composite on said patch; h) if necessary, curing the multilayer composite at a preferred curing temperature of approximately 350 Fahrenheit for a preferred duration of between about 30 and 35 seconds; and i) applying said patch to an article.
[0048] The method may further comprise the step of marking the garment with a design and/or indicia indicating the source of the souvenir (e.g., the number and/or name of the sports participant or team who used the souvenir in the sporting event). The souvenir may be any desired item which is recycled and applied to any desired object. For example, a tire that has been used by a race car may be the recycled souvenir which is applied to a garment. Race cars are known to use several sets of tires during a single race. These used tires are then discarded as with regular automobile and truck tires which typically end up in a land fill, with tremendous negative impact to the environment. These tires may instead be recycled into a particulate and applied to merchandise objects in accordance with the teachings of the present invention.
[0049] Examples of other souvenir items may include, for example, hockey pucks used in a hockey game, skateboards or skateboard wheels used by a famous skateboarder, a football helmet from a famous football player, a football used in a football game, a baseball, bat or helmet used in a baseball game, soccer shin pads or a soccer ball used in a soccer game, etc. The particulate may be left in the color of the original souvenir or optionally colored (e.g., by spraying or soaking the particulate with an ink).
[0050] The above-mentioned invention and method of manufacture are unique in that they provide not only the opportunity for fans to own a souvenir, but also provide for an extremely realistic facsimile of the original collectible souvenir material making the overall product appealing in a way that no prior art has been able to accomplish. In particular, the distribution of the recycled particulate directly into and/or onto the adhesive layer allows many options for creating the desired visual and tactile (e.g., 3D) pattern. The particulate laydown pattern may thus be customized as desired to achieve a very close simulation (or playful exaggeration or deliberate non-simulation, if desired) of the original souvenir type and/or characteristic and/or material(s).
BRIEF DESCRIPTION OF THE DRAWING
[0051] FIG. 1 a and 1 b are front and rear views, respectively, of a t-shirt according to one embodiment of the invention;
[0052] FIGS. 2 a and 2 b are front and rear views, respectively, of a cap according to another embodiment of the invention;
[0053] FIGS. 3 a , 3 b and 3 c are front, rear and side views, respectively, of a sweatshirt according to another embodiment of the invention;
[0054] FIGS. 4 a and 4 b are front and rear views, respectively, of a glass according to another embodiment of the invention;
[0055] FIG. 5 is a front view of a bag according to another embodiment of the invention;
[0056] FIG. 6 is a block diagram of the individual layers according to an embodiment of the invention;
[0057] FIG. 7 is a fragmented view of FIG. 3 b showing an application of the invention with examples of particulate laydown patterns; and
[0058] FIGS. 8A-8D are simplified side elevational views of particulate laydown patterns and a decal embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0059] Referring now to the drawing, there is seen in FIGS. 1 a and 1 b a first embodiment of the invention in the form of a t-shirt designated generally by the reference numeral 10 having a front 10 a and rear 10 b. Any part of t-shirt 10 may have a pattern and design and/or indicia applied thereto in accordance with the inventive method described above. In this embodiment, the recycled souvenir is a used tire from the car of race car driver Bob Smith driving car number “93” and the article to which the recycled souvenir is applied is a t-shirt. More particularly, the used tire (not shown) is converted (e.g., by grinding) into particulate and applied to any part of t-shirt 10 (in this example, to rear surface 10 b ) in a souvenir design pattern 12 which resembles a tire track. Indicia indicating the source of the souvenir is placed on the article and may be applied over a portion of or adjacent to pattern 12 . In the present example, the indicia is the name of the race car driver “Bob Smith” and the number of his race car “93” as indicated by reference numerals 14 and 16 , respectively. The race car driver's signature 18 may also be applied as indicia. A potential purchaser may thus instantly recognize the source of pattern 12 although further identifying detail may be provided if desired (e.g., a tag or label attached to the t-shirt indicating the tire track is from the actual used tire of car 93 driven by Bob Smith).
[0060] FIGS. 2 a and 2 b show a second embodiment of the invention in the form of a baseball cap designated generally by the reference numeral 20 having a front 20 a and rear 20 b. Any part of cap 20 may have a pattern and design and/or indicia applied thereto in accordance with the inventive method described above. In this embodiment, the recycled souvenir is a helmet used in a game by player number “37” and the article to which the recycled souvenir is applied is a baseball cap. More particularly, the used helmet (not shown) is ground into particulate and applied to any part of cap 20 (in this example, to front surface 20 a ) in a souvenir pattern 22 which resembles a helmet. Indicia indicating the source of the souvenir is applied over a portion of or adjacent to pattern 22 . In the present example, the indicia is the player and the player's number “37” as indicated by reference numeral 24 and 26 , respectively. A potential purchaser may thus instantly recognize the source of pattern 22 although further identifying detail may be provided if desired (e.g., a tag or label attached to the cap indicating the helmet is from an actual helmet used in a game by Player 37).
[0061] FIGS. 3 a , 3 b and 3 c show a third embodiment of the invention in the form of a sweat shirt designated generally by the reference numeral 30 having a front 30 a, a rear 30 b and sleeves 30 c. Any part of sweatshirt 30 may have a pattern and design and/or indicia applied thereto in accordance with the inventive method described above. In this embodiment, the recycled souvenir is a used baseball bat used in a game by player “99” and the article to which the recycled souvenir is applied is a sweatshirt. More particularly, the used baseball bat (not shown) is ground into particulate and applied to any part of sweatshirt 30 (in this example, to rear surface 30 a ) in a souvenir pattern 32 which resembles a baseball bat. Indicia indicating the source of the souvenir is applied over a portion of, adjacent to pattern 32 or anywhere else on sweatshirt 30 . In the present example, the indicia is an outline of the player and the player's number “99” as indicated by reference numerals 34 and 36 , respectively. A potential purchaser may thus instantly recognize the source of pattern 32 although further identifying detail may be provided if desired (e.g., a tag or label attached to the sweatshirt indicating the baseball bat design is from the actual baseball bat used in a game by player number 99).
[0062] FIGS. 4 a and 4 b show a third embodiment of the invention in the form of a drinking glass designated generally by the reference numeral 40 having a front 40 a and rear 40 b. Any part of glass 40 may have a pattern and design and/or indicia applied thereto in accordance with the inventive method described above. In this embodiment, the recycled souvenir is the used hockey puck used in a game by player having the number “97” and the article to which the recycled souvenir is applied is a drinking glass. More particularly, the used hockey puck (not shown) is ground into particulate and applied to any part of glass 40 (in this example, to front surface 40 a ) in a souvenir pattern 42 which resembles a hockey puck. Indicia indicating the source of the souvenir is applied over a portion of or adjacent to pattern 42 . In the present example, the indicia is the player and the player's number “97” as indicated by reference numeral 44 and 46 , respectively. A potential purchaser may thus instantly recognize the source of pattern 42 although further identifying detail may be provided if desired (e.g., a tag or label attached to the glass indicating the puck design is from the actual puck used in a game by player number 97).
[0063] FIG. 5 shows a fourth embodiment of the invention in the form of a tote bag designated generally by the reference numeral 50 having a front panel 50 a. Any part of bag 50 may have a pattern and design and/or indicia applied thereto in accordance with the inventive method described above. In this embodiment, the recycled souvenir is a used skateboard and the article to which the recycled souvenir is applied is a tote bag. More particularly, the used skateboard (not shown) and/or wheels is ground into particulate and applied to any part of bag 50 (in this example, to front surface 50 a ) in a souvenir pattern 52 which resembles a skateboard. Indicia indicating the source of the souvenir is applied over a portion of or adjacent to pattern 52 . In the present example, the indicia is the skateboarder as indicated by reference numeral 54 . A potential purchaser may thus instantly recognize the source of pattern 42 although further identifying detail may be provided if desired (e.g., a tag or label attached to the bag indicating the skateboard design is from the actual skateboard used by a particular skateboarder.
[0064] As stated above and referring to FIG. 6 , in a first embodiment, the method for applying the recycled souvenir particles to an article 60 comprises the steps of:
a) converting (e.g., by grinding) at least a portion of said souvenir into a particulate; b) screen printing a colored ink layer 62 onto the article 60 in a desired recycled souvenir design pattern (which may be a representation of the nature of the recycled souvenir (e.g., if the souvenir is a hockey puck, the pattern may be designed to look like a hockey puck)); c) screen printing a first coat liquid adhesive layer 64 onto the colored ink layer 62 ; d) distributing the particulate 66 onto said liquid adhesive layer 64 ; e) removing excess particulate from the article not located or bonded on the liquid adhesive layer (e.g., by vacuum pick-up); f) drying (e.g., flash drying) the first coat liquid adhesive layer and thereby bonding with the particulate thereto the first coat liquid adhesive layer on to form a first bonded layer 70 at a preferred drying temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; g) screen printing a second coat liquid adhesive layer 68 onto the first bonded layer and thereby forming a multilayer composite 72 ; h) if necessary, curing the multilayer composite 72 (e.g., via conveyor oven at a preferred curing temperature of approximately 350 Fahrenheit for a preferred duration of between about 30 and 35 seconds); and i) if necessary, heat pressing the multilayer composite 72 at a temperature of approximately 375 degrees Fahrenheit for a preferred duration of between about 15 and 18 seconds.
[0074] The laydown pattern of the individual particles may be random or customized as desired to achieve the desired visual and tactile effect. For example, as seen in FIG. 7 , souvenir pattern 32 is formed in the shape of a baseball bat. A recycled baseball bat is converted into a particulate with the desired particle size and shape such as indicated at boxes 80 , 82 , 84 and 86 . Box 80 illustrates a particulate composition and laydown pattern having a mixture of very small particles 80 a combined with randomly shaped and interspersed large, medium and small particles 80 b - d , respectively.
[0075] Box 82 illustrates a particulate composition and laydown pattern having only randomly shaped and interspersed large, medium and small particles 82 a - c , respectively.
[0076] Box 84 illustrates a particulate composition and laydown pattern having small linear particles 84 a oriented in the same direction with an interior design 84 b formed to simulate wood grain (or any other desired design such as a player's number or team, for example) which may be formed with colored ink or particles which are colored darker than background particles 80 a.
[0077] Box 86 illustrates a particulate composition and laydown pattern 86 a which provides a gradient effect. This may be done using particles that have been colored in different shades and laying them down on the article with the different shades separated to provide the desired gradient effect.
[0078] FIG. 8 a illustrates a simplified section view of an article such as t-shirt 10 having design 32 formed using a particulate composition having oblong shaped particles 90 which are all of the same size and oriented in the same direction. Various methods may be used to achieve the desired orientation of the particles during the laydown process including using particle orientation frames which physically direct the particles into the desired orientation. Additional materials may also be added to the particulate for this purpose and/or for additional design effect, e.g., adding metal filings which would allow the use of magnets to orient the filing/particle mixture.
[0079] FIG. 8B illustrates a simplified section view of an article such as t-shirt 10 having design 32 formed using a particulate composition having oblong shaped particles 92 of different sizes and oriented in the same direction.
[0080] As noted above the particle orientation and particle shapes may be of any desired combination.
[0081] As an alternative to forming the design pattern directly on the article, FIGS. 8C and 8D illustrate an alternate method where the design pattern is formed as a patch or decal 100 (e.g., applique, transfer, iron-on, press-on, sew-on, static cling, etc.) which may be separately formed either as a unitary piece (decal) or onto any desired piece of material, e.g., fabric, (patch) which is subsequently attached to the desired article. In the embodiment where the back surface of the unitary design or decal includes an adhesive backing for adhesively applying the design/decal to the article, a protective release paper 102 may be applied to the adhesive back surface of the design/decal which may be removed immediately prior to applying the design/decal to the desired article. It can be seen in FIG. 8C that the particle composition and orientation in this example is varied including both oriented particles 104 and non-oriented or randomly placed particles 106 . According to the “decal” embodiment, the method comprises the steps of:
a) converting at least a portion of said souvenir into a particulate; b) providing an adhesive backing layer on a non-binding release paper; c) screen printing a colored ink layer onto the adhesive backing layer in a desired pattern which may be a representation of the nature of or characteristic of the recycled souvenir (e.g., if the souvenir is a hockey puck, the pattern may be designed to look like a hockey puck); d) screen printing a first coat liquid adhesive layer over the colored ink layer; e) distributing the particulate onto said liquid adhesive layer; f) removing excess particulate from the article not located or bonded on the liquid adhesive layer; g) drying (e.g., flash drying) the first coat liquid adhesive layer with the particulate thereon to form a first bonded layer at a preferred temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; h) screen printing a second coat liquid adhesive layer onto the first bonded layer and thereby forming a multilayer composite; i) if necessary, curing the multilayer composite via conveyor oven at a curing temperature of approximately 350 Fahrenheit for a duration of between about 30 and 35 seconds; and j) if necessary, heat pressing the multilayer composite at a temperature of approximately 375 degrees Fahrenheit for between about 15 and 18 seconds to thereby form the design pattern as a decal; and k) removing the decal from the release paper and applying the decal to an article.
[0093] The steps may be combined and/or performed in a different order (e.g., the colored ink and first coat adhesive layer may be combined prior to screen printing. In this embodiment the particulate composition may have a particulate size of preferably between about 0.1 and 1500 microns, more preferably between about 0.5 and 800 microns and most preferably between about 1 and 400 microns.
[0094] According to the “patch” embodiment, the method comprises the steps of:
a) converting at least a portion of said souvenir into a particulate; b) screen printing a colored ink layer onto a patch of material in a desired pattern; c) screen printing a first coat liquid adhesive layer over the colored ink layer; d) distributing the particulate onto said liquid adhesive layer; e) removing excess particulate from the article not located or bonded on the liquid adhesive layer; f) drying (e.g., flash drying) the first coat liquid adhesive layer with the particulate thereon to form a first bonded layer, the drying step optionally being with applied heat at a preferred temperature of approximately 300 degrees Fahrenheit for a preferred duration of between about 15 and 20 seconds; g) screen printing a second coat liquid adhesive layer onto the first bonded layer and thereby forming a multilayer composite on said patch; h) if necessary, curing the multilayer composite at a preferred curing temperature of approximately 350 Fahrenheit for a preferred duration of between about 30 and 35 seconds; and i) applying said patch to an article.
[0104] The following is a non-limiting list of examples of the types of articles on which the inventive method may be used:
[0105] Adhesive Notes, Antenna Pennants, Ash Trays, Automotive Gift Sets, Automotive Emergency Kits, Awards, Plaques and Trophies, Backpacks, Badges and Holders, Bag Clips, Bags, Balls, Bandages and Dispensers, Bandanas, Bar Gifts and Accessories, Bats, Battery-Operated Cars, Beach Items, Beach Towels, Beads, Belts, Belt and Fanny Packs, Big & Tall Apparel, Billiard Accessories, Billiard Cues, Billiard Gift Sets, Binders, Binoculars, Blankets, Bobble heads, Books, Bookmarks, Bottle and Can Openers, Bowling Balls, Bowling Pins and Equipment, Bowls, Briefs, Bracelets, Briefcases, Bumper Stickers, Business Cards and Cases, Buttons, Calculators, Calendars, Cameras, Can and Bottle Coolers, Can and Bottle Drink Sleeves, Candles, Candy Jars, Caps, Car Accessories (Flags, Magnets and Shades), Card Games, Carabiners, Cards (playing/greeting/trading), Carriers, Cases, Cell Phone Accessories, Chairs (Deck, Director, Folding, etc.), Chalk Boards, Checkbook Covers, Christmas and other Ornaments, Cigar Gift Sets and Accessories, Cinch Bags, Clips, Clipboards, Clocks, Coasters, Coats, Coffee Mugs (ceramic and metallic), Coins, Collectibles & Memorabilia, Collectible Stamps, Computer Bags, Accessories and Gift Sets, Containers, Cookie Jars, Coolers (soft and hard sided), Cooler Tailgate Tubs, Corkscrews, Covers, Coozies (aka Cozies and/or Koozies), Crystal, Cuff Links, Custom Gear including Customizable Apparel (your name in collectible material), DVDs & Books, Day Packs, Decals, Decorations, Desk Sets, Desk Top Awards, Accessories and Organizers, Diaries, Desk pads, Diecast Cars, Trucks, other equipment and vehicles and Cases, Displays, Dog Tags, Door Mats, Drinkware, Driving Experience Products and Accessories, Duffel Bags, Ear Buds, Ear Phones, Ear Rings, Electronics, Erasers, Executive Gift Sets, Fans, Fitness and Personal Safety Products, Flags & Banners, Flashlights, Flatware, Flip Flops, Flying Discs, Folders, Folios, Footwear, Frames, Friction and/or Pullback Vehicles, Gambling Sets and Accessories, Games, Gifts & Seasonal, Gift Baskets, Glasses, Globes, Gloves, Golf Equipment and Gift sets (containing or partially containing golf balls, head covers, shoe bag, iron cleaning brush, wooden tees, towel, ball marker chips, tees, travel bag and cart/carrying bag), Glassware, Hats and Headwear, Helmets & Accessories, Headphones and Headsets, Headrest Covers, Highlighters, Hitch Covers, Home & Office, Housewares, Ice Scrapers, Jackets, Jewelry, Jotters, Journals, Keys, Key Blanks, Key Chains and Key Fobs, Kitchenware, Knives, Ladder Mount Plaques, Lamps, Lanyards and Badge Holders, Laptop Computer Skins, Laser Pointer, Letter Opener, License Plates and Holders, Lighters, Lip Balms, Luggage, Luggage Tags, Lunch Bags and Boxes, Magnets, Markers and Marker Boards, Mats, Meal Carriers/Lunch Kits, Media Cases, Mice, Mini-Bats, Mini-Pucks, Mini-Balls, Mini-Wheels, Mini-Sticks, Mini-Sneakers, Mini-Mouse Pads, Mugs, Multi-Tools, Nail Files, Napkin Holders, NASCAR Gear, Necklaces, Neoprene Drink Koozies, Notebooks, Notepads, Officeware, Padfolios, Panoramas, Papers, Paper Clips, Paper Weights, Pens, Pencils, Pennants, Pet Harnesses, Collars, Leashes and Accessories, Photo or Picture Frames, Pins, Ping Pong Tables, Paddles and Balls, Picnic and BBQ Products, Pill Boxes, Pins, Pit Shirts, Place Mats, Planners, Plastic Model Kit cars, Plates, Plush Novelties, Poker and other game Tables, Poker Chips, Ponchos, Portable Bars, Portfolios, Posters, Prints, Programs, Pucks, Purses, Puzzles, Radios, Remote Control Cars (light/sound/action), Rings, Rulers, Sandals, Seat Belt Covers, Shaving Kit/Bag, Shoes, Shot Glasses, Sleeves, Spa Accessories, Spare Wheel Covers, Speakers, Sport Bottles, Sporting Goods, Stadium Seats, Stands, Staplers, Stationery, Stools, Stress Balls, Sunglasses, Sweatshirts, Hoodies & Fleece, Swimming Pool Sets and Accessories, T-Shirts, Tables (folding and otherwise), Tailgating Accessories, Tank Tops, Tape Measures, Tattoos, Tents (camping, outfitter and screened-in tents), Thermometers, Thimbles, Throw Blankets with Sleeves, Tins (containers), Tires, Toiletry Bags, Tools, Tool Bags, Tool Kits, Totes, Toys, Travelware, Tumblers, Umbrellas, Undergarments, Uniforms, USB accessories, Utensils, Utility Kits, Vases, Vinyl Stickers and Decals, Wall Graphics, Wallets and Money Clips, Watches, Water Bottles and Jugs with and without Sleeves, Wheels, White Boards, Window Clings, Wine Stoppers, Women's Apparel, Wrist Bands. | Articles created using particulate from recycled souvenirs and a method of decorating articles such as garments with patterns made from ground particulate obtained from noteworthy spectator sport objects such as race car tires, for example, wherein the pattern resembles the nature or characteristic of the recycled item. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to lock systems and more particularly pertains to an automatic door locking/unlocking device for an automotive vehicle which is designed to automatically lock and unlock the vehicle's doors.
2. Description of the Prior Art
The use of automatic locking and unlocking devices for vehicles is known in the prior art. For example, U.S. Pat. No. 4,502,718, which issued to Sasaki, et al on Mar. 5, 1985 discloses a door lock/unlock system for an automotive vehicle to include a safety device for preventing a mis-operation thereof. Another patent of interest is U.S. Pat. No. 4,709,776 which issued to Marcus Metz on Dec. 1, 1987 and which is directed to an electrical circuit that automatically locks door locks of a motor vehicle at a predetermined speed. A further patent of interest is U.S. Pat. No. 4,848,114 that issued to Mary Rippe on Jul. 18, 1989 and directed to a locking system for the doors of an automotive vehicle.
While all of these above-mentioned patents illustrate the fact that automatic locking technology is available in the prior art, non of these devices and their associated circuits provide for both automatic locking and unlocking of vehicle doors without any driver input. As such, there appears to be a need for some type of device which would provide both automatic locking and unlocking of vehicle doors without driver input and in this respect, the present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of automatic locking systems now present in the prior art, the present invention provides an improved automatic locking and unlocking system for a vehicle wherein the same can be used to automatically lock and unlock vehicle doors without driver assistance. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved automatic locking and unlocking system for a vehicle which has all the advantages of prior art automatic locking and unlocking systems and none of the disadvantages.
To attain this, the present invention essentially comprises an automatic locking and unlocking unit for a vehicle which will lock the doors of the vehicle when the ignition is turned on and will eventually unlock the doors when the ignition is turned off. The unit senses voltage levels in the wires attached to the ignition lock and then activates the appropriate functional circuit to either lock or unlock the doors.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
It is therefore an object of the present invention to provide a new and improved automatic locking and unlocking unit for a vehicle which has all the advantages of the prior art automatic locking and unlocking units for a vehicles and none of the disadvantages.
It is another object of the present invention to provide a new and improved automatic locking and unlocking unit for a vehicle which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new and improved automatic locking and unlocking unit for a vehicle which is of a durable and reliable construction.
An even further object of the present invention is to provide a new and improved automatic locking and unlocking unit for a vehicle which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such automatic locking and unlocking units for a vehicle economically available to the buying public.
Still yet another object of the present invention is to provide a new and improved automatic locking and unlocking unit for a vehicle which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is an electrical schematic of the automatic locking and unlocking unit for a vehicle comprising the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIG. 1 thereof, a new and improved automatic locking and unlocking unit for a vehicle embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
Initially, with no key in the vehicle's ignition and with the vehicle's engine turned off, the unit 10 is in a standby mode. Points A and B, which are start and ignition connections from the vehicle's ignition lock harness, are at this time being provided with no voltage so that the inputs at the AND gate 12 and the NOR gate 14 are being grounded by R1 and R2.
With both inputs low, the output of the AND gate 12 is low and regardless of the electrical state of the bilateral gate BG1, there will be no voltage to trigger the one-shot OS-L causing a low output and no base voltage to turn the transistor TRL on, whereby no locking of the vehicle's doors will occur.
The NOR gate 14, however, with its inputs low will produce a high output state. This high state could trigger one-shot OS-U but since the bilateral gate BG2 is non-conductive (hi-z state), no voltage will reach the trigger input of the one-shot OS-U, and the same cascade effect of low output will not produce an unlocking.
FF is a JK flip-flop set up to have Q high and Q' low. At this stage of operation, the flip-flop FF is acting as an unlock disabler and a lock enabler. Once the key is in the ignition and is switched from the "ignition" or "on" position to a "start" position, the AND gate 12 will produce a high output that will trigger the one-shot OS-L. The output of the one-shot OS-L will put enough voltage at the base of the transistor TRL to turn it on and produce a locking of the doors. The output of the one-shot OS-L (and also one-shot OS-U) is a one second pulse determined by Rt and Ct.
The output of the one-shot OS-L is at the same instant fed through diode D1 to the clock and K input of the flip-flop FF. This causes the flip-flop FF to toggle its values to Q=low and Q'=high which results in a disable mode for the lock circuit and an enable mode for the unlock circuit.
Since the inputs for the NOR gate 14 are no longer both low, the output will be low and no triggering of the one-shot OS-U will occur. When the key is taken out of the ignition, both inputs of the NOR gate will be low so as to produce a high output and since the bilateral gate BG2 is now conductive, an unlocking will occur. The Q output of the one-shot OS-U is fed through the diode D2 to the flip-flop FF causing it once more to toggle its values so as to enable the lock circuit and disable the unlock. This of course is the standby mode.
It is important to note that a locking action must occur to enable the unlock circuit. The bilateral gates BG3, BG4 are being fed by the opposite circuit's complementary output. The only task of this circuit is to protect the car's lock and unlock actuators from being driven from simultaneous pulses.
As to the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | An automatic locking and unlocking unit for a vehicle will lock the doors of the vehicle when the ignition is turned on and will eventually unlock the doors when the ignition is turned off. The unit senses voltage levels in the wires attached to the ignition lock and then activates the appropriate functional circuit to either lock or unlock the doors. | 4 |
[0001] This application is a continuation of U.S. application Ser. No. 13/712,946, which disclosure is hereby incorporated herein in its entirety.
TECHNICAL FIELD
[0002] This application relates in general to lubricants.
BACKGROUND
[0003] A bicycle chain is a roller chain that transfers power from the pedals to the drive-wheel of a bicycle which propels it. Many bicycle chains are made from plain carbon or alloy steel with some plated with nickel for example to reduce rust and allow for some self-lubrication. Bicycle chains come in a variety of shapes and sizes and most are often referred to as roller chains. Roller chains are one of the most efficient and cost effective ways to transmit mechanical power between two shafts (i.e. the bicycle crank shaft and the rear axle). The general construction of a roller chain consists of two alternating link assemblies and when put together create a chain segment. The outer link assembly usually consists of two outer link side plates containing two link pins. The inner link assembly usually consists of two inter link bushings and two link rollers. Therefore one chain segment usually consists of eight separate components with six moving contact points. FIG. 1 is a schematic of a chain link segment.
[0004] An average bicycle chain has about forty to fifty segments, therefore 320 to 400 separate components with 240 to 300 moving parts and all of these parts are directly exposed to the environment (e.g., water and dirt).
[0005] A variety of mechanisms exist for reducing the transfer of power in the chain drive. Frictional, impact and chain deformation are the predominant energy loss mechanisms. Frictional losses cannot be recovered during operation and this energy is dissipated as heat. Impact losses describe the interactions between the chain and the sprockets and chain deformation results from the offset angle of the chain. Frictional losses account for the majority of the energy loss and are a product of the coefficient of friction and the normal force acting over the contacting chain surfaces.
[0006] The following may be useful to the reader:
[0007] Plant-derived oils are defined as oils that were produced from plant sources, as opposed to animal fats or petroleum. There are three primary types of plant oils, differing both by the means of extracting the relevant parts of the plant, and in the nature of the resulting oil. (1) Vegetable oils are historically extracted by putting part of the plant under pressure and squeezing out the oil. (2) Macerated oils consist of a base oil to which parts of plants are added and (3) essential oils are composed of volatile aromatic compounds, extracted from plants by distillation.
[0008] Vegetable oils are what are most commonly considered plant oils. These are triglyceride-based and include oils such as canola oil, soybean oil, sesame seed oil, rape seed oil, peanut oil, palm oil, olive oil, neatstool oil, menhadden oil, linseed oil, cotton seed oil, corn oil, coconut oil, sunflower oil, safflower oil and castor oil to name a few. The oils are extracted from the plant (usually the seed) by compressing the plant under pressure.
[0009] Canola oil is a vegetable oil which refers to a cultivar of either rapeseed ( Brassica napus L.) or field mustard ( Brassica campestris L. or Brassica Rapa var.). Canola oil is a pale yellow liquid with a mild or no odor or taste. Its boiling point is 225° F. (107° C.) with a density of 910 kg/m 3 . It has a flash point of 600° F. (315° C.). Its seeds are used to produce edible oil suitable for consumption by humans. Canola oil can be obtained from several commercial sources including ADM Agri-Industries, Ltd. (Decatur, Ill.) and Cargill, Inc. (Minneapolis, Minn.).
[0010] Castor oil is a vegetable oil obtained from the castor bean (i.e. castor seed), Ricinus communis (Euphorbiaceae). Castor oil is a colorless to pale yellow liquid with mild or no odor or taste. Its boiling point is 595° F. (313° C.) with a density of 961 kg/m 3 . It has a flash point of about 445° F. (229° C.). Its seeds are used to produce edible oil suitable for consumption by humans. Castor oil can be obtained from several commercial sources including Welch, Holme & Clark Company, Inc. (Newark, N.J.) and Jedwards International, Inc. (Quincy, Mass.).
[0011] Mineral oil is any various colorless, odorless, light mixture of alkanes in the C 15 to C 40 range from a non-vegetable (mineral) source particularly a distillate of petroleum. Other names such as white oil, liquid paraffin and liquid petroleum have been used. Refined mineral oil can be purified and certain grades are safe for human consumption. Mineral oil can be substituted for some plant oil content in the disclosed invention.
[0012] Polyolefin is a polymer produced from a simple olefin called an alkene with the general formula C n H 2n . For example, polyethylene is the polyolefin produced by polymerizing the olefin ethylene. Polyolefins have chemical resistance and very low surface energies. Polyolefins with 15 or less carbons are more likely to be soluble in plant-based oils and produce lubricants with a viscosity suitable for bicycle chain applications.
[0013] Poly-alpha-olefin is a specific type of polyolefin where the carbon-carbon double bond starts at the alpha-carbon atom (i.e. the double bond is between the first and second carbons in the molecule). Many poly-alpha-olefins are safe for human contact. A few examples of poly-alpha-olefins which are food-grade compatible (H-1) include CAMCO FMO-5, FMO-15, FMO-32, FMO-46 and FMO-100 from CAMCO Lubricants (St. Paul, Minn.) and Omnilube FGH 1022, FGH 1032, FGH 1046, FGH 1068, FGH 1100 and FGH 1150 from UltraChem, Inc. (New Castle, Del.).
[0014] Polyalkylene glycol is a specific type of condensation polymer from ethylene oxide and water. Polyalkylene glycols generally have much better load and wear properties compared to petroleum oils and poly-alpha-olefins. A few examples of polyalkylene glycols which are food-grade compatible (H-1) include PG 130 FG and PG 220 FG from UltraChem, Inc.
[0015] BioBlend MP22 is a biodegradable plant-based oil which is used for a variety of applications including chain and cable applications. BioBlend MP22 is produced by BioBlend Renewable Resources, LLC (Joliet, Ill.).
[0016] Antioxidants inhibit oxidation of molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals which in turn can start chain reactions. Antioxidants are important in lubricants and can prevent the formation of gums that interfere with the operation of the lubricating surfaces. There are hundreds of water and oil soluble antioxidants. Many food grade phenolic-based and aromatic amine-based antioxidants exist. A few examples of oil soluble antioxidants which are safe for human contact include vitamin E, butylated hydroxytoluene, butylated hydroxyanisole, and omega 3 fatty acids. Vitamin E is the collective name for a set of eight related tocopherols and tocotrienols with antioxidant properties. Omega 3 fatty acids are a blend of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).
[0017] Aqueous soluble dyes which are food grade compatible include Food, Drug and Cosmetic (FC&C) dyes such as FD&C #40 (red), FD&C #3 (red), FD&C #5 (yellow), FD&C #6 (orange), FD&C #1 (Blue), FD&C #2 (Blue), FD&C #3 (Green), Orange B and Citrus Red #2. Oil soluble dyes which are safe for human contact include Drug and Cosmetic dyes such as D&C #6 (green), D&C #17 (red), D&C #11 (yellow) and D&C #2 (violet). The dyes are available from Sensient Colors, Inc. and Spectra Colors Corporation. Some aqueous soluble dyes maybe used by first dissolving in propylene glycol or other suitable solvent before dissolving in the plant based oils.
[0018] Bioderived is defined to mean the mixture contains equal to or greater than 77 weight percent of a biobased product. The USDA BioPreferred program requires chain and cable lubricants to contain equal to or greater than 77 weight percent of a biobased product.
[0019] Biobased is defined to mean a product that contains organic carbon. In other words, carbon that did not originate from petroleum or petroleum-based products. The biobased content can be determined by measuring the amount of carbon-13 in the product using ASTM Method D6866, Standard Test Methods for Determining the Biobased Content of Natural Range Materials Using Radiocarbon and Isotope Ratio Mass Spectrometry Analysis.
[0020] Flammable liquid is defined as one with a flash point below 100° F. (37.8° C.). Less-flammable liquids with a flash point between 100° F. (37.8° C.) and 200° F. (93.3° C.) are defined as combustible liquids. This definition is used by the National Fire Protection Association, the U.S. Department of Transportation, the U.S. Environmental Protection Agency, the U.S. Occupational Safety the Health Administration and others.
[0021] NSF International is a not-for-profit, non-governmental organization that provides standards development, product certification, auditing, education and risk management for public health and safety. NSF is a World Health Organization collaborating center for food and water safety and indoor environment.
[0022] Food Grade Lubricants are acceptable for use in meat, poultry and other food processing equipment, applications and plants. The lubricant types in food-grade applications are broken into categories based on the likelihood they will contact food. The USDA created the original food-grade designations H1, H2 and H3, which is the current terminology used. The approval and registration of a new lubricant into one of these categories depends on the ingredients used in the formulation.
[0023] H1 Lubricant is a food-grade lubricant used in food processing environments where there is some possibility of incidental food contact. Lubricant formulations may only be composed of one or more approved basestocks, additives and thickeners listed in Guidelines of Security Code of Federal Regulations (CFR) Title 21, 178.3570.
[0024] H2 Lubricant is a lubricant used on equipment and machine parts in locations where there is no possibility that the lubricant or lubricated surface contacts food. Because there is not the risk of contacting food, it does not have a defined list of acceptable ingredients. They cannot, however, contain intentionally added heavy metals such as antimony, arsenic, cadmium, lead, mercury or selenium. Also, the ingredients must not include substances that are carcinogens, mutagens, teratogens or mineral acids.
[0025] H3 Lubricant is a lubricant also known as a soluble or edible oil. It is used to clean and prevent rust on hooks, trolleys, and similar equipment.
[0026] Biodegradable is the chemical breakdown of the base oil and additives into carbon dioxide and water, in the presence of organisms, air, and water.
[0027] Inherently Biodegradable means at least 20% of the product will have biodegraded in 28 days or less.
[0028] Readily Biodegradable or Ultimately Biodegradable means that 60% or more of the product will have biodegraded in 28 days or less.
SUMMARY
[0029] This application relates to a multi-purpose lubricant which is formulated for use on items, such as, but notwithstanding, bicycle chains that is bioderived, nonflammable, biodegradable, and environmentally safe with a low coefficient of friction and lubricant loss rate. The lubricant during use may also attract and retain minimal dirt particles and is easy to clean from the chain surfaces.
[0030] In accordance with one implementation, a lubricant comprises food grade based oils substantially complying with USDA H-1 specifications for incidental contact with food, wherein at least one oil is selected from the group consisting of food grade plant oil, food grade poly-alpha-olefin, polyalkylene glycol, and mixtures thereof.
[0031] In accordance with another implementation, a lubricant comprises canola oil, castor oil and a poly-alpha-olefin.
[0032] In accordance with yet another implementation, a lubricant comprises canola oil, castor oil and a polyalkylene glycol.
[0033] In accordance with yet another implementation, a lubricant comprises an oil substantially complying with USDA H-2 specification wherein the oil is at least one item selected from the group consisting of plant oil, poly-alpha-olefin, polyalkylene glycol, and mixtures thereof.
[0034] The details of one or more implementations are set forth in the accompanying drawing and the description below. Other features, aspects, and advantages will become apparent from the description, the drawing, and the claims. It is to be understood that the foregoing general description and the detailed description are exemplary, but not restrictive of the lubricant or the method for making the lubricant.
DESCRIPTION OF DRAWINGS
[0035] In the drawing, which is discussed herein, an implementation of a chain link segment is illustrated. It is understood that the lubricant is not limited to being applied to the implementation depicted in the drawing, but rather may be used on other types of chains, equivalent structures or items to be lubricated.
[0036] FIG. 1 shows a schematic of a chain link segment.
DETAILED DESCRIPTION
[0037] While the specification concludes with claims particularly pointing out and distinctly claiming subject matter, the lubricant will now be further described by reference to the following detailed description of exemplary implementations taken in conjunction with the above-described accompanying drawing. The following description is presented to enable any person skilled in the art to make and use the lubricant. Descriptions of specific implementations and applications are provided only as non-limiting examples and various modifications will be readily apparent to those skilled in the art. The general principles defined herein may be applied to other implementations and applications without departing from the spirit and scope of the lubricant. Thus, the lubricant is to be accorded the widest scope encompassing numerous alternatives, modifications, and equivalents consistent with the principles and features disclosed herein. For purpose of clarity, details relating to technical material that is known in the technical fields related to the lubricant have not been described in detail so as not to unnecessarily obscure the present application.
[0038] In some implementations, a lubricant for bicycle chains and other mechanisms is made by combining canola oil, castor oil and a poly-alpha-olefin or polyalkylene glycol. In some implementations, this combination forms a thin, penetrating multi-function film over the entire chain mechanism by balancing a combination of properties including chain wet ability, metal affinity, anti-wear and anti-friction elements.
[0039] In some implementations, the canola oil is plant-derived. Canola oil has lubricating properties, including chain wet ability and low coefficient of friction. In some implementations, the canola oil content may vary from about 1 to about 80 weight percent.
[0040] In some implementations, the castor oil is plant-derived. It is a triglyceride and has a great affinity for metal surfaces. Castor oils also have lubrication properties, including good low temperature viscosity properties. In some implementations, the castor oil content may vary from about 1 to about 75 weight percent. In some implementations, higher concentrations of castor oil may be used, but in some cases depending on the amount of poly-alpha-olefin present, the mixture may form two phases. For example, a mixture containing about 77 weight percent castor oil, about 20 weight percent poly-alpha-olefin and about 3 weight percent canola oil may separate into two-phases. Ideally the lubricant components remain completely miscible, but in the event the lubricant components separate, the user would shake the bottle before use to ensure a uniform mixture was applied to the bicycle chain or mechanism to be lubricated.
[0041] Regarding the poly-alpha-olefin or polyalkylene glycol, many poly-alpha-olefins have flexible alkyl branching groups on every other carbon of their polymer backbone chain. These alkyl groups which can shape themselves in numerous conformations make it difficult for the polymer molecules to line themselves up side-by-side in an orderly way. Therefore, many poly-alpha-olefins do not crystallize or solidify easily and are oily, viscous liquids even at low temperature. At least for these reasons, low molecular weight poly-alpha-olefins are synthetic lubricants with low coefficient of friction and anti-wear properties.
[0042] In some implementations, the poly-alpha-olefin content may vary from about 1 to about 20 weight percent. In some implementations, higher concentrations of poly-alpha-olefin may be used, but in some cases depending on the amount of castor oil present, the mixture may form two phases. For example, a mixture containing about 40 weight percent poly-alpha-olefin, about 50 weight percent castor oil and about 10 weight percent canola oil may separate into two phases. Ideally the lubricant components remain completely miscible, but in the event the lubricant components separate, the user would shake the bottle before use to ensure a uniform mixture was applied to the bicycle chain or mechanism to be lubricated. In some implementations, a polyalkylene glycol may be used instead of or in addition to the poly-alpha-olefin. Polyalkylene glycols are lubricants having a low coefficient of friction and anti-wear properties. Polyalkylene glycols also generally perform better at higher temperatures than poly-alpha-olefins. Mixtures of poly-alpha-olefins and polyalkylene glycols may also be used in combination with canola oil and castor oil.
[0043] In order to measure the chain drive efficiency and study the effect of lubrication on chain link performance, a test stand was constructed. The stand consisted of two shafts connected by a standard bicycle chain. The front shaft was driven by an adjustable speed motor with a speed and power sensor and was connected to a standard Shimano bicycle front chain ring with 52 teeth. The rear shaft was connected to a second power sensor with a standard Shimano rear cassette and derailleur unit. The rear cassette had ten chain rings with 11, 12, 14, 15, 17, 18, 19, 21, 23 and 25 teeth. The rear shaft also was connected to a mechanical braking system and a tensioner so that a constant load could be applied to simulate actually riding conditions. To determine the chain drive efficiency, the ratio of the power output divided by the power input was calculated at several speeds and power outputs with various gear ratios using the rear cassette.
[0044] The standard conditions selected for comparison to determine the improvements with and without lubrication on the chain were 60 revolutions per minute (rpm) with a front shaft power output of 100 watts (W) using the 52/15 front ring/cassette ring combination. A baseline experiment was conducted with a clean dry chain with no lubricant which resulted in a chain drive efficiency of about 90±1%.
[0045] The same experiment was repeated after applying a lubricant to the chain comprising a mixture of canola oil, castor oil and a poly-alpha-olefin (PAO) or polyalkylene glycol (PAG). In some implementations, an antioxidant and dye were added to reduce oxidation and alter the color of the otherwise pale yellow to clear oils. In some implementations, the antioxidant content may vary from 0 to 5 weight percent and the dyes from 0 to 0.1 weight percent.
[0046] Examples 1 to 6 measure the chain drive efficiency performance of mixtures containing canola oil, castor oil and PAO with and without additives. Examples 7 to 9 measure the chain drive efficiency performance of mixtures containing canola oil and lubricant additives purchased from BioBlend Renewable Resources with castor oil in various proportions. Examples 10 to 15 measure the chain drive efficiency performance of mixtures containing canola oil, castor oil and PAG with and without additives. In all cases the chain drives efficiency improved by 1 to 3%.
Example 1
[0047] A lubricant containing about 80 weight percent food grade canola oil, 10 weight percent food grade castor oil and 10 weight percent poly-alpha-olefin (Omnilube FGH 1022) was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 50 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 93±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 2.3±0.5%.
Example 2
[0048] A lubricant containing about 80 weight percent food grade canola oil, 10 weight percent food grade castor oil, 9 weight percent poly-alpha-olefin (Omnilube FGH 1022), 0.95 weight percent vitamin E antioxidant and 0.05 weight percent annatto dye was mixed together for twenty minutes to form a miscible yellow solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 50 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 93±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 2.4±0.5%.
Example 3
[0049] A lubricant containing about 45 weight percent food grade canola oil, 45 weight percent food grade castor oil and 10 weight percent poly-alpha-olefin (Omnilube FGH 1032) was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 200 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 92±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.7±0.5%.
Example 4
[0050] A lubricant containing about 45 weight percent food grade canola oil, 45 weight percent food grade castor oil, 9 weight percent poly-alpha-olefin (Omnilube FGH 1032), 0.93 weight percent omega 3 fatty acid antioxidant and 0.07 weight percent chlorophyll dye was mixed together for twenty minutes to form a green miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 200 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 92±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.9±0.5%.
Example 5
[0051] A lubricant containing about 15 weight percent food grade canola oil, 75 weight percent food grade castor oil and 10 weight percent poly-alpha-olefin (Omnilube FGH 1022) was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 400 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 91±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.5±0.5%.
Example 6
[0052] A lubricant containing about 15 weight percent food grade canola oil, 75 weight percent food grade castor oil, 9 weight percent poly-alpha-olefin (Omnilube FGH 1022), 0.92 weight percent butylated hydroxyanisole antioxidant and 0.08 weight percent paprika oleoresin dye was mixed together for twenty minutes to form a red miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 400 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 91±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.5±0.5%.
Example 7
[0053] A lubricant containing about 75 weight percent BioBlend MP22 and 25 weight percent food grade castor oil was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm 3 and a viscosity of about 100 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 92±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 2.0±0.5%.
Example 8
[0054] A lubricant containing about 50 weight percent BioBlend MP22 and 50 weight percent food grade castor oil was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 200 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 92±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.8±0.5%.
Example 9
[0055] A lubricant containing 25 weight percent BioBlend MP22 and 75 weight percent food grade castor oil was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm 3 and a viscosity of about 400 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 91±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.6±0.5%.
Example 10
[0056] A lubricant containing about 80 weight percent food grade canola oil, 10 weight percent food grade castor oil and 10 weight percent polyalkylene glycol (Omnilube PG 130 FG) was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 55 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 93±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 2.2±0.5%.
Example 11
[0057] A lubricant containing about 80 weight percent food grade canola oil, 10 weight percent food grade castor oil, 9 weight percent polyalkylene glycol (Omnilube PG 130 FG), 0.97 weight percent vitamin E antioxidant and 0.03 weight percent D&C Yellow #11 was mixed together for twenty minutes to form a miscible yellow solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 55 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 93±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 2.3±0.5%.
Example 12
[0058] A lubricant containing about 40 weight percent food grade canola oil, 50 weight percent food grade castor oil and 10 weight percent polyalkylene glycol (Omnilube PG 130 FG) was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 220 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 92±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.6±0.5%.
Example 13
[0059] A lubricant containing about 40 weight percent food grade canola oil, 50 weight percent food grade castor oil, 9 weight percent polyalkylene glycol (Omnilube PG 130 FG), 0.98 weight percent omega 3 fatty acid antioxidant and 0.02 weight percent D&C Green #6 was mixed together for twenty minutes to form a green miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 220 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 92±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.7±0.5%.
Example 14
[0060] A lubricant containing about 10 weight percent food grade canola oil, 80 weight percent food grade castor oil and 10 weight percent polyalkylene glycol (Omnilube PG 130 FG) was mixed together for twenty minutes to form a miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 450 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 91±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.2±0.5%.
Example 15
[0061] A lubricant containing about 10 weight percent food grade canola oil, 80 weight percent food grade castor oil, 9 weight percent polyalkylene glycol (Omnilube PG 130 FG), 0.99 weight percent butylated hydroxyanisole antioxidant and 0.01 weight percent D&C red #17 dye was mixed together for twenty minutes to form a red miscible solution at room temperature. The lubricant had a density of about 0.9 g cm −3 and a viscosity of about 450 centipoise at 21 degrees Celsius. The lubricant mixture was applied to a bicycle chain and the excess wiped off with a rag, leaving behind a thin film of lubricant. The bike chain was installed in a test stand to measure the mass and frictional loss. The drive chain efficiency was measured at about 100 watts and 60 rpm to be about 91±1%. The chain was carefully removed and the weight compared before and after operation. The lubricant mass loss was calculated to be about 1.3±0.5%.
[0062] A lubricant mixture containing about 80 weight percent canola oil, 10 weight percent castor oil and 10 weight percent poly-alpha-olefin with and without antioxidant and dye showed an improvement in chain drive efficiency of about 3±1%. A lubricant mixture containing about 45 weight percent canola oil, 45 weight percent castor oil and 10 weight percent poly-alpha-olefin with and without antioxidant and dye showed an improvement in chain drive efficiency of about 2±1%. A lubricant mixture containing about 15 weight percent canola oil, 75 weight percent castor oil and 10 weight percent poly-alpha-olefin with and without antioxidant and dye showed an improvement in chain drive efficiency of about 1±1%.
[0063] A lubricant mixture containing about 75 weight percent BioBlend MP22 and 25 weight percent castor oil showed an improvement in chain drive efficiency of about 2±1%. A lubricant mixture containing about 50 weight percent BioBlend MP22 and 50 weight percent castor oil showed an improvement in chain drive efficiency of about 2±1%. A lubricant mixture containing about 25 weight percent BioBlend MP22 and 75 weight percent castor oil showed an improvement in chain drive efficiency of about 1±1%.
[0064] A lubricant mixture containing about 80 weight percent canola oil, 10 weight percent castor oil and 10 weight percent polyalkylene glycol with and without antioxidant and dye showed an improvement in chain drive efficiency of about 3±1%. A lubricant mixture containing about 40 weight percent canola oil, 50 weight percent castor oil and 10 weight percent polyalkylene glycol with and without antioxidant and dye showed an improvement in chain drive efficiency of about 2±1%. A lubricant mixture containing about 10 weight percent canola oil, 80 weight percent castor oil and 10 weight percent polyalkylene glycol with and without antioxidant and dye showed an improvement in chain drive efficiency of about 1±1%.
[0065] The viscosity of a lubricant is an important factor in determining the lubricant-film thickness. A critical film thickness is required in order to minimize the coefficient of friction. If the lubricant is too thin, the film thickness may become too small and friction may increase. If the lubricant is too thick, it may become difficult for the lubricant to penetrate into and between the links and rollers and surface wettability may decrease leading to an increase in friction.
[0066] Examples 1 to 15 also show a correlation exists between the lubricant's absolute viscosity and the chain drive efficiency. The density and viscosity of each lubricant mixture was measured using a pycnometer and rheometer, respectively, at room temperature (about 70° F. or about 21° C.). The mixture containing 80 weight percent canola oil, 10 weight percent castor oil and 10 weight percent poly-alpha-olefin had an absolute viscosity of about 50 centipoise at room temperature. The mixture containing 45 weight percent canola oil, 45 weight percent castor oil and 10 weight percent poly-alpha-olefin had an absolute viscosity of about 200 centipoise at room temperature. The mixture containing 15 weight percent canola oil, 75 weight percent castor oil and 10 weight percent poly-alpha-olefin had an absolute viscosity of about 400 centipoise at room temperature. The mixture containing 25 weight percent BioBlend MP22 and 75 weight percent castor oil had an absolute viscosity of about 400 centipoise at room temperature. The mixture containing 50 weight percent BioBlend MP22 and 50 weight percent castor oil had an absolute viscosity of about 200 centipoise at room temperature. The mixture containing 75 weight percent BioBlend MP22 and 25 weight percent castor oil had an absolute viscosity of about 100 centipoise at room temperature. The mixture containing 80 weight percent canola oil, 10 weight percent castor oil and 10 weight percent polyalkylene glycol had an absolute viscosity of about 55 centipoise at room temperature. The mixture containing 40 weight percent canola oil, 50 weight percent castor oil and 10 weight percent polyalkylene glycol had an absolute viscosity of about 220 centipoise at room temperature. The mixture containing 10 weight percent canola oil, 80 weight percent castor oil and 10 weight percent polyalkylene glycol had an absolute viscosity of about 450 centipoise at room temperature. The ideal absolute viscosity range for many riding styles and environmental conditions is about 50 to 450 centipoise at room temperature.
[0067] The lubricants' ability to adhere to the chain is another parameter to be considered. The lubricant should remain on the chain while in motion and not “fly-off” the surface of the chain. If the lubricant viscosity is below about 50 centipoise, it has a greater tendency to “fly-off” the chain because it is too thin. The lubricants' adherence was measured by carefully weighing the dry chain, applying lubricant on the chain and using a rag to wipe off any excess lubricant. The chain was mounted in the test stand which was run for about 1 hour at 60 rpm, 100 watt load in the 52/15 front ring/cassette ring combination. Examples 1 to 15 demonstrate several mixtures which were prepared and the lubricant mass loss measured. In all cases the chain lost some lubricant from about 1.5% to 2.3%.
[0068] A lubricant mixture containing 80 weight percent canola oil, 10 weight percent castor oil and 10 weight percent poly-alpha-olefin with and without antioxidant and dye had an average lubricant mass loss of 2.3±0.5%. A lubricant mixture containing 45 weight percent canola oil, 45 weight percent castor oil and 10 weight percent poly-alpha-olefin with and without antioxidant and dye had an average lubricant mass loss of 1.8±0.5%. A lubricant mixture containing 15 weight percent canola oil, 75 weight percent castor oil and 10 weight percent poly-alpha-olefin with and without antioxidant and dye had an average lubricant mass loss of 1.5±0.5%. A lubricant mixture containing 75 weight percent BioBlend MP22 and 25 weight percent castor oil had an average lubricant mass loss of 2.0±0.5%. A lubricant mixture containing 50 weight percent BioBlend MP22 and 50 weight percent castor oil had an average lubricant mass loss of 1.8±0.5%. A lubricant mixture containing 25 weight percent BioBlend MP22 and 75 weight percent castor oil had an average lubricant mass loss of 1.6±0.5%. A lubricant mixture containing 80 weight percent canola oil, 10 weight percent castor oil and 10 weight percent polyalkylene glycol with and without antioxidant and dye had an average lubricant mass loss of 2.2±0.5%. A lubricant mixture containing 40 weight percent canola oil, 50 weight percent castor oil and 10 weight percent polyalkylene glycol with and without antioxidant and dye had an average lubricant mass loss of 1.6±0.5%. A lubricant mixture containing 10 weight percent canola oil, 80 weight percent castor oil and 10 weight percent polyalkylene glycol with and without antioxidant and dye had an average lubricant mass loss of 1.2±0.5%.
[0069] Therefore a balance of properties may be used when formulating a multi-purpose lubricant. In some implementations, the multi-purpose lubricant may be used for bicycle chains. The canola oil provides chain wet ability and a low coefficient of friction. Mixtures containing high content of canola oil (about 80 weight percent) showed the highest chain drive efficiency (3% improvement); however this may be balanced with the lubricant mass loss which also was high at about 2.3%. The castor oil provides lubrication and affinity for metal surfaces with low mass loss of about 1.5%; however this may be balanced with the lower chain drive efficiency (1% improvement). A mixture containing 45 weight percent canola oil, 45 weight percent castor oil and 10 weight percent of poly-alpha-olefin may provide an overall balance between chain drive efficiency (2% improvement) and lubricant mass loss (1.8%). The same is true for a mixture containing 40 weight percent canola oil, 50 weight percent castor oil and 10 weight percent of polyalkylene glycol with the best overall balance between chain drive efficiency (2% improvement) and lubricant mass loss (1.6%). As mentioned earlier, another component of the lubricant mixture is a poly-alpha-olefin or polyalkylene glycol. Because plant oils can oxidize over time and become gummy, the addition of the poly-alpha-olefin or polyalkylene glycol reduces gum formation. These additives also reduce the coefficient of friction and improve the thermal and oxidative stability of the mixture. Additional antioxidants and dyes also may be added. The mixtures containing BioBlend MP22 perform in a similar fashion to those using canola oil.
[0070] In some implementations, a blend of canola oil and castor oil with poly-alpha-olefins and polyalkylene glycols minimizes gum formation. In some implementations, in order to prevent gum formation at temperatures experienced with normal bicycle operation (i.e. about 0 to 120° F. or −18 to 49° C.) in air, at least about 2 weight percent poly-alpha-olefin or polyalkylene glycol or mixtures of both should be added. Other commercially available oils such as BioBlend MP22 may be substituted for canola oil in the formulations set forth herein.
[0071] In some implementations, the canola oil and castor oil may be bioderived. In some implementations, the combined mass of the canola and castor oils may be at least 77 weight percent so that the environmental impact of the lubricant may be minimized. The USDA BioPreferred program has established for chain and cable lubricants a minimum bioderived content of 77 weight percent. In some implementations, the poly-alpha-olefin and polyalkylene glycol may be either bioderived or synthetic. In some implementations, the poly-alpha-olefin and polyalkylene glycol may be a combination of bioderived and synthetic.
[0072] In some implementations, the lubricant mixture may be nonflammable. Canola oil, castor oil, most poly-alpha-olefins (C 6 to C 14 ) and polyalkylene glycols have a boiling point and flash point which exceed 200° F. (93.3° C.); therefore they are defined as combustible liquids and are classified as nonflammable. In some implementations, a nonflammable bicycle lubricant may be an important safety feature for bicycle chain oils which are often applied indoors in confined spaces where the risk of ignition may be present. In some implementations, nonflammable bicycle lubricants may be an important feature for transportation and storage.
[0073] In some implementations, the lubricant may be non-toxic. Canola oil and castor oil are both obtainable as food-grade products. Many poly-alpha-olefins and polyalkylene glycols are used in a variety of personal care products and are considered safe in case of incidental food contact. In some implementations, due to the importance of maintaining the safety of users applying these lubricants, the components should be classified as either H-1 or H-2 and approved by the United States Department of Agriculture (USDA). Organizations such as NSF International use these classifications to protect consumers and ensure products are certified and meet safety specifications. H-1 is a stringent classification for lubricants approved for incidental food contact. The H-2 classification is for uses where there is no possibility of food contact and seeks to assure that no known poisons or carcinogens are used in the lubricant. In some implementations, the present bicycle oils may be formulated to meet H-1 and H-2 classification. H-1 approved oil and the term “food grade” will be used interchangeably for the purpose of this application.
[0074] In some implementations, the lubricant may pick up minimal dirt particles from road and trail surfaces. In some implementations, the lubricant may not wash off when riding in wet conditions. In some implementations, the lubricant may be formulated so that the chain can be easily cleaned with a rag leaving behind a minimal residue.
[0075] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosures in this application. As a non-limiting example, additional components may be added to those described above, or components may be removed or rearranged.
[0076] Other implementations are within the scope of the following claims. | A multi-purpose lubricant is described. In accordance with one implementation, a lubricant comprises food grade based oils substantially complying with USDA H-1 specifications for incidental contact with food, wherein at least one oil is selected from the group consisting of food grade plant oil, food grade poly-alpha-olefin, polyalkylene glycol, and mixtures thereof. In accordance with another implementation, a lubricant comprises canola oil, castor oil and a poly-alpha-olefin. In accordance with yet another implementation, a lubricant comprises canola oil, castor oil and a polyalkylene glycol. In accordance with yet another implementation, a lubricant comprises an oil substantially complying with USDA H-2 specification wherein the oil is at least one item selected from the group consisting of plant oil, poly-alpha-olefin, polyalkylene glycol, and mixtures thereof. In some implementations, the multi-purpose lubricant may be applied to areas of a bicycle chain. | 2 |
The present invention generally relates to post and panel type walls. More particularly, the present invention concerns an improved post for use in connection with panel walls of the free-standing variety.
In recent years, many civil engineering projects have required the placement of a free-standing barriers along project boundaries to control environmental radiated energy problems and to create opaque walls. Typical radiated energy problems include noise, electromagnetic energy, and nuclear radiation. Each of these problems is potentially a two way problem. More particularly, in some applications it is desired to keep the energy out of an area while in other applications it is desired to keep the energy in a particular area.
As used in this patent, free-standing means a non-loadbearing wall structure which extends upwardly above an underlying ground surface so that both sides are exposed to wind loading, air borne chemicals, scouring, and other environmental weather including ultraviolet radiation and fungi. Commonly, undulating barriers use a zigzag or other offset arrangement of panels that is self-supporting. One offset type barrier system is illustrated and described in U.S. Pat. No. 4,111,401 which was issued Sept. 5, 1978 to William H. Pickett. An example of a structure having the zigzag type is illustrated in U.S. Pat. No. 3,732,653 which issued May 15, 1973 to William H. Pickett.
In many municipal areas, the practical availability or cost of purchasing rights-of-way for civil engineering projects has created a need for an environmental barrier system which extends in a more generally straight line than the zig zag or offset type systems. Such a straighter line arrangement for an environmental barrier thus minimizes the additional right-of-way that must be acquired for the project when compared to a sound barrier systems which use offsets, zigzags and the like. Undulating barrier systems prove less costly than straight line systems when adequate and inexpensive right-of-way space is available.
When free-standing undulating barrier systems are converted to straight line systems, post and panel arrangements have generally been found to be preferable to other systems such as embedding panels. In a post and panel arrangement, a plurality of posts are spaced at predetermined distances from one another along the desired line for the barrier. When the posts are set in position, panels of metal, concrete, wood, plastic or the like are supported between adjacent posts to create the barrier structure which will attenuate radiated energy or block sight.
Known post and panel systems experience a variety of problems and use limitations. One problem associated with these known post and panel systems is the need to very precisely position adjacent posts if prefabricated panels are to be positioned therebetween. The positioning problem include not only the post-to-post spacing but also the plumbness of the post both to the wall face and the panel edge. Once the panel dimensions are selected and the panels are fabricated, then the spacing between adjacent posts must correspond to the panel length for the full exposed length of the post. If this positioning is not maintained, then the panels will not be accepted between posts (spacing too close) or the panels cannot be attached to the posts (spacing too great). In a species of the latter case, a poor acoustic joint may result requiring specialized treatment. This spacing problem can be exacerbated by the comparatively large fabrication tolerances which in the case of a precast concrete elements may be in the neighborhood of plus or minus one quarter inch.
Another problem with the post and panel barrier arrangements is the exposure of the wall to design wind pressure. Since environmental walls may be quite high (for example, on the order of 35 ft.), a substantial surface area is presented by the panels which can be acted upon by wind pressure. In some localities wind velocities as high as 120 mph can be expected corresponding to wind pressure loadings of about 46 pounds per square foot. In such localities, posts supporting the panels must be designed with full cognizance of the expected, and aberrational once-in-50-year, design wind pressure levels that may be acting upon the wall during its life. Additionally, the design physics of such wind pressures are increased by gust, drag and safety factors.
Customarily, posts for such post and panel walls, as well as for fencing, have been designed by determining the maximum force load conditions that will be exerted on the posts. Typically, the post comprises a member cantilevered out of the earth or some other structure which partially supports each of the adjacent panels. In such an arrangement, the maximum force load condition ordinarily occurs near the grade level, that is, the area where the post enters the underlying ground or other support structure.
In the past, posts have ordinarily been made from tree trunks, rolled and extruded metal shapes, cast concrete and the like. Economy of fabrication has dictated heretofore that the post have a uniform cross section from one end to the other, the cross-sectional dimensions being selected to accomodate the maximum force load condition. Thus, little or no effort was made in the past to optimize the post design and structure for the loading conditions to which the post would be exposed.
More recently, some posts have been fabricated from precast concrete. In keeping with tradition, these concrete posts are generally provided with a uniform cross-section. However, any post whether of wood, metal or concrete, having a uniform cross-sectional shape is not significantly stressed at all cross sections and, therefore, is not efficiently used. Consequently, substantial amounts of structural material are wasted; adding considerably to the material expense for the post and shipping costs for delivering the post to a job site.
The manufacturing and placement tolerances discussed above in connection with post spacing also create problem for precast concrete posts. Since the tolerances in both the post and panel fabrication can accumulate along with the post spacing and verticality tolerances, the accumulation of tolerances can lead to a loose joint between panels and posts. With a loose joint, vibration can occur, and sound, light and radiation energy can pass through the barrier structure as well.
Another problem associated with a straight line post and panel system concerns thermally induced linear expansion and contraction after erection. Such thermal variations in the wall can lead to loose joints during contraction as discussed above, structural damage of the posts and panels due to compressive stress developed during expansion, and difficulty in construction when large thermal variations occur.
Accordingly, it is apparent that the need continues to exist for a post and panel barrier system which overcomes problems of the type discussed above.
SUMMARY OF THE INVENTION
The present invention overcomes problems of the type discussed above by providing a precast concrete post, having a cross section which varies from a first location adjacent the top to a second location adjacent to the bottom or, at least, spaced from the first location. The variation in post cross-sectional size is determined such that an essentially constant maximum bending stress is provided anywhere in the post between the two locations under the design conditions. In this manner, material usage in the post is optimized and material waste is minimized.
In addition, in order to relax the acceptable tolerances for post-to-post spacing, a resilient joint packing may be provided. This resilient packing expands or contracts as necessary to accomodate tolerance accumulations resulting from build up of casting tolerances as well as post-to-post spacing. Moreover, thermal expansion and contraction can be accomodated with the joint packing.
The problems of spacing tolerances and linear thermal expansion may also be accomodated in the post and panel barrier construction of this invention by use of a folded plate panel assembly between adjacent posts. This folded plate panel assembly has an articulatable joint between adjacent sections of the panel assembly. Articulation of the joint occurs if, as, and when thermal expansion so requires. In addition, the articulatable joint is useful to further relax the tolerances on post-to-post spacing. The resilient joint packing can be used in combination with, and as an alternate to, the folded plate panel assembly.
To provide flexibility in the post and panel system to accommodate changes and ground surface elevation, the post may be provided with a plurality of lateral channels to receive corresponding connecting devices. The connecting devices attach panel assemblies to the associated posts. By providing these channels at conveniently spaced apart locations along the length of the post, panel elevation can be adjusted to accommodate ground contour changes in a step-up fashion.
Furthermore the post panel and connector parts of this invention permit the wall to follow horizontal and vertical curves. Moreover, corners in the wall from essentially 0° to essentially 360° may be negotiated by the wall.
BRIEF DESCRIPTION OF THE DRAWINGS
Many objects and advantages of the present invention will be apparent to those skilled in the art when this specification is read in conjunction with the attached drawings wherein like reference numerals have been applied the like elements and wherein:
FIG. 1 is a perspective view of a post and panel wall constructed in accordance with one embodiment of the barrier system of the present invention;
FIG. 2 is a perspective view of a post constructed in accordance with the present invention;
FIG. 3 is an enlarged plan view of the post of FIG. 2;
FIGS. 4, 5 and 6 are plan views of alternate cross-sectional embodiment of the post illustrated in FIG. 2;
FIG. 7 is an enlarged cross-sectional view taken along the line 7--7 of FIG. 1;
FIG. 8 is a cross-sectional view, similar to FIG. 7, illustrating a 90° corner with posts and panels of the present invention;
FIG. 9 is a perspective view of a second embodiment of the barrier system of the present invention;
FIG. 10 is a plan view of a portion of the wall of FIG. 9;
FIG. 11 is an enlarged cross-sectional view, similar to FIG. 7, illustrating a 0° corner using posts and panels of the present invention;
FIG. 12 is a front elevational view showing a first embodiment of vertical support for wall panels;
FIG. 13 is a front elevational view showing a second embodiment of vertical support for wall panels; and
FIG. 14 is an elevational view showing the elevation adjustment possible with the present post and panel system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIG. 1, a privacy wall 20 for controlling sight, sound, fire, trespass, drift, erosion or radiated energy is positioned along a side boundary of a civil engineering structure 21 such as a highway. The wall 20 has post and panel construction. The wall 20 includes a plurality of precast concrete posts 22 each of which is preferably spaced from adjacent posts by a uniform predetermined distance along a generally straight line. While uniform post spacing is preferable, in some application the spacing may be variable. Typical distances between posts are, for example, 20, 25 and 30 ft.
Each post 22 extends vertically out of the underlying ground 24 to a height which is generally coextensive with the barrier height. Typical heights for the barrier range from 5 to 30 feet. If the barrier is used for security purposes, additional security devices including fencing may be mounted to the tops of the posts.
Spanning the distance between adjacent posts 22 is a panel means 26 for establishing the privacy barrier. Each panel means 26 has a pair of generally parallel side edges 28, 30 each edge being attached to a corresponding post adjacent to that side edge. Where the height of the wall 20 becomes particularly large, for example, in excess of 10 ft, it will ordinarily be desirable to use a plurality of vertically stacked panel elements to give the panel means 26 the requisite height. The height of these component panel elements lies in the range of 8 to 12 feet and is selected such that individual panel elements can be readily transported by commonly available vehicles in compliance with highway regulations.
Each post 22 (see FIG. 2) includes a front surface 32, a rear surface 34, and a pair of generally parallel side surfaces 36, 38. The distance between the front and rear surfaces 32, 34 defines a post thickness; similarly, the distance between side surfaces 36, 38 defines a post width.
Generally speaking, the post 22 has a cross-sectional area which varies from a first location near the free end to a second location remote from the free end of the post. In a typical design, the first location will be located at the top of the post 40. The second location 42 will be spaced from the top 40 of the post and will typically be located at the bottom of the exposed portion of the post 22. More particularly, the second location 42 would ordinarily be positioned at approximately the grade level where the post 22 projects vertically upwardly out of the underlying ground.
To support the post 22 in its vertically upstanding position, any one of a multitude of suitable conventional foundations may be used. For example, caissons may be provided from which the post 22 projects upwardly or, the post 22 may include an elongated portion projecting downwardly beyond the second location 42 so that the post can be driven into the underlying soil or supported by a cast-in-place footing.
As noted, the cross-sectional area of the post 22 (FIG. 2) varies between the first location 40 and the second location 42. In most cases, the cross-sectional area will be symmetrically distributed in each of two planes. One plane of symmetry is vertical and lies in the plane between two adjacent posts. The second plane of symmetry is also vertical but is perpendicular to the first plane of symmetry, i.e., normal to the plane between adjacent posts. However, there may be applications where symmetry in one or both such planes is not needed or not desired.
The cross-sectional area variation between the first and second locations is selected to provide optimal material utilization in the post 22 and thereby minimize the weight of the post 22, minimize the material cost for the post, and provide standardization of design. The cross-sectional area variation from the first location 40 to the second location 42 is determined such that an essentially constant maximum bending stress exists in the post 22 between the first location 40 and the second location 42. In making this bending stress determination, the presence of steel reinforcements in the concrete material must be considered. For simplicity, the reinforcements are not illustrated in the various illustrations here.
In a preferred embodiment of the post 22, the post width is essentially constant from the first location 40 to the second location 42 (the second plane of symmetry being parallel to the side surfaces 36, 38); and, the depth of the post between the front surface 32 and the back surface 34 provides the cross-sectional area variation between the two spaced locations 40, 42 (the first plane of symmetry being essentially equidistant from the front and back surfaces 32, 34). With this arrangement of surfaces on the post 22, the thickness variation between the two locations 40, 42 can be most easily designed to give the constant maximum bending stress.
The above reference to an essentially constant maximum bending stress allows economy in form construction for casting the concrete post 22. More specifically, it may be more convenient in the molding operation to develop the contour of the front surface curve 32 and the rear surface curve 34 from chord-like straight line approximations to the design curve. These straight line approximations to the curves will allow some deviation from the constant maximum bending stress that might otherwise be attainable with a post designed strictly in accordance with the present invention.
In establishing the post depth variation between the first location 40 and the second location 42 the forces acting upon the post 22 must be considered. These forces must include, the maximum design wind pressure to which the wall of FIG. 1 is exposed multiplied by an appropriate safety factor, gust factor and drag factor. It will be noted that the wind pressure acting on a structure is non-uniform and varies approximately as elevation (i.e. distance of any point above the ground surface) raised to the 1/7th power, i.e., p h 1/7 . Wind pressure, p, is assumed to act on the surface area of the panel means 26 extending between adjacent posts as well as the posts 22 themselves. And, the wind pressure distribution (i.e., vertical intensity) is determined by considering the topography around the wall site. That portion wind pressure acting on the panel means is applied to the post as a distributed force extending between the first and second locations 40, 42.
Weight of the panel means themselves, in addition to the weight of the posts, resists the toppling effect of wind pressure on the posts; thus wall panels must also be included in the analysis. These various weights contribute a greater stability to the wall against toppling as one progresses from the top of the post 40 to the bottom of the post 42. This enhanced stability is in part due to the increasing moment arm about which toppling must occur, which moment arm corresponds to about one-half the depth of the post 22 at any given elevation.
In some instances where right-of-way width permits, the panel means extending between adjacent posts is folded about a hinge line intermediate the adjacent posts (see, for example, FIGS. 9, 10 and 12-14). In such instances, the effect of the folded panel means can provide further substantial resistance to overturning by wind pressure loading because the assembly has a wider base moment arm on which its stabilizing weight may act. Accordingly, when the post thickness variation is being developed using the folded plate, the effective wall stability due to a hinged or folded panel means must also be included to optimize post configuration.
Each side surface 36, 38 (FIG. 2) of the post 22 is provided with a corresponding groove 44, 46 (FIG. 3). Each groove 44, 46 extends from the top of the post 22 to the bottom of the post and cooperates with a conformingly shaped edge from the panel means positioned between adjacent posts. In the preferred embodiment, the grooves 44, 46 are arcuate in cross-sectional shape and comprise a circular arc of approximately 90°. The radius of the arc is selected to conform to the radius provided on the corresponding side edges 28, 30 (FIG. 1) of the panel means 26 positioned between adjacent posts 22.
While the grooves 44, 46 (FIG. 3) are preferably arcuate, it is also within the scope of the present invention to form those grooves from other shapes. For example (FIG. 4), the grooves 44', 46' are fashioned from two planar segments which appear in cross section as straight line elements 48, 50. These straight line elements can approximate an arcuate shape if desired. Here again, casting considerations for the post 22 may suggest the desirability of utilizing straight line elements in forming the grooves 44', 46'.
In FIG. 5, the grooves 44", 46" are again made up from a plurality of planar segments which appear as straight line elements 52, 54, 56 in cross section. A multiplicity of line elements give a better approximation of the desired arcuate shape. As another feature, each of the grooves 44", 46" is recessed beneath laterally projecting shoulders 58, 60 that are integrally cast with the corresponding side surfaces 36, 38 of the post 22. The shoulder 58, 60 can be used in any of the embodiments. As shown in FIG. 5, the bottom of the grooves 44", 46" intrude beyond the plane of the corresponding side surface 36, 38 into the central portion of the post 22. As the depth of the groove 44", 46" (measured from the bottom of the groove 44", 46" to the plane of the corresponding side surface 36, 38) decreases and the bottom of the groove approaches the plane of the corresponding post-side surface, there is an increase in the range of angles at which the post 22 and panel means can be connected. For example, the post and panel system can be designed to accommodate angles essentially from 0° to 360°, (FIG. 11).
A post 22 suitable for applications where wall panels are at angles from 0° to 360° to one another is illustrated in FIG. 6. Here, each groove 44, 46 is arcuate in cross section and subtends an angle of about 90° about its corresponding center. The bottom of each groove 44, 46 is essentially tangential to the plane of the corresponding side surface 36, 38. At each side of each groove 44, 46, the shoulders 58, 60 restrain a panel means from slipping along the plane of the side surfaces 36, 38. To permit sealing between the panel means and the corresponding groove, each groove 44, 46 may be provided with a slot 59 which extends radially into the post body from the bottom of the groove. The slot 59 has a depth away from the groove sufficient to retain a resilient packing.
To facilitate connecting the wall panel means 26 to the post 22 (see FIG. 2), each post is provided with a plurality of channels 62. Each channel 62 extends between the side surfaces 36, 38 (FIG. 7), is aligned to be tangential to the bullnose 70, 70' of each panel means 26, 26' adjacent to the post 22 and has a counterbore at each place where it meets a side of the post 22. In addition, each channel 62 has a cross-sectional size which is selected to permit a flexible tensile connector to pass therethrough. These channels 62 may be regularly spaced in pairs along the entire length of the post 22.
Ordinarily, the connecting means 64 will attach one panel means 26' to one side of the post 22. As shown in FIG. 7, the connector means 64 attaches the panel means 26' to the post 22 whereas the connector means 64' attaches the panel means 26 to the post 22. As seen from FIG. 7, the two connector means 64, 64' do not lie in the same horizontal plane. Spaced above or below the connecting means 64 is a second connecting means 64' which attaches the second panel means 26 to the opposite side of the post 22. Each panel means 26, 26' is attached to the post 22 by at least two vertically spaced connectors 64. If desired, the connecting means could simultaneously attach both panel means 26, 26' to the post 22. Moreover, if desired the channels 62 could have other configurations.
While at least two pairs channels 62 will be necessary to attach most panel means 26 to the post 22, a larger number of channel pairs 62 are typically provided. These additional channel pairs 62 provide a means for adjusting the vertical height of panel means 26 relative to the post 22 while using the same type of connecting assembly. Ordinarily, the channels 62 will be provided at vertically spaced increments which correspond to the minimum desired height increment between panel means in adjacent portions of the wall.
The channel 62 (see FIG. 7) is sized to permit workmen to manipulate a connecting means 64 through the post 22 in order to attach adjacent wall panel means 26, 26' to the post. In its preferred form, the connecting means 64 comprises a flexible tensile element which is attached at each end in a corresponding counterbore of the channel 62. The connecting means 64 biases the respective panel means 26, 26' toward each other and into engagement with the corresponding grooves 44, 46 provided in the side surfaces 36, 38 of the post 22. A suitable, flexible tensile element is illustrated, for example, in U.S. Pat. No. 4,111,401, the contents of which are incorporated herein by this reference thereto.
As will be seen from FIG. 7, each side edge 30, 28 of the wall panel means 26, 26' has a shape which conforms to the cross-sectional shape of the corresponding groove 44, 46 provided in the post 22. In this embodiment, the side edges 28, 30 of the panel means are contoured so as to be arcuate in cross section. Moreover, the cross-sectional arc of the panel means preferably extends for an angle of approximately 270° symmetrically disposed about a central plane. A pair of shoulders 66, 68 extend backwardly from the rounded or bullnose side edges 30, 28 to the front and rear planar surfaces of the wall panel means 26. The radius of the bullnose end 70 is preferably selected to be equal to at least half the thickness of the wall panel 26. That bullnose 70 must, however, be positioned in the groove so that there is overlap of panel material and post material. Thus, material of the panel means 26 would shear material of the post 22 and adequate retention is attained. That is, the packing material 72 should not be relied upon to restrain movement of the panel means along the faces 36, 38 unless the packing material has a shear strength equivalent to the post material.
The foregoing relationship between the radius of the bullnose 70 and the thickness of the panel 26 permits the wall panel 26" (FIG. 8) to be moved relative to the post 22 so that the wall panel 26" creates an essentially right angle relative to the plane of the wall panel 26 approaching the post 22 from the left. Clearly, the wall panel 26" could assume any angle less than 90° with respect to the lateral plane of the post 22. If both panels are attached to the post 22 so as to define the maximum external angle, an angle of essentially 360° can be obtained (FIG. 11).
In typical precast concrete construction, tolerances of ±1/4 inch or more are common, depending on experience of fabricators and cost of forms. Accumulations of such tolerances require that positioning and placement of posts 22 be very precise in order to accommodate the precast panel means 26 therebetween. Precise tolerances on the lateral spacing between posts can be very difficult to maintain at construction sites. To overcome the problems with precise tolerances, a joint packing material 72 (FIG. 7) may be provided between the bullnose 70 and the adjacent groove 44, as well as between the bullnose 70' and the adjacent groove 46. The packing material 72 extends from the top of the post 22 to the bottom of the post along the entire length of the groove 44, 46. The width of the packing material may be selected to be approximately coextensive with the formed post surfaces defining each groove 44, 46.
The thickness of the packing material 72 is selected such that it will be compressed partially when the minimum size bullnose 70 cooperates with the deepest groove 44, 46 and the shortest panel means 26 is positioned between two posts with the maximum distance therebetween. In addition, the packing material 72 will accommodate compression that results when the largest bullnose 70 is received by the shallowest groove 44 when the longest panel means 26 is positioned between two posts with the minimum distance therebetween. In this fashion, the maximum bullnose 70 can also be accommodated by the shallowest groove 44 with the packing material 72 not being compressed to such a degree that it will prohibit placement of the panels 26 between adjacent posts. If desired, the packing material 72 may be formed as a flat sheet or as a preformed arcuate member having a shape corresponding approximately to the shape of the grooves 44, 46. It is not necessary, however, that the packing material 72 be coextensive with the arcuate dimension of the groove since, for acoustic purposes, only a simple blockage is needed.
The cross-sectional shape of the bullnose 70 conforms to the cross-sectional shape of the groove 44, 46. This correspondence may be essentially exact as in the case when no packing material 72 is employed, i.e., the bullnose radius and the groove radius may be equal. Alternatively, the bullnose 70 may have a radius which is less than the radius of the groove 44 by an amount corresponding to about one-half the compressible thickness of the gasket material 72. In this fashion, the packing material 72 will be subjected to essentially radial compression when the attachment means 64 connects adjacent panels 26, 26" with the post 22.
With a packing material 72 having a thickness as described, the packing material 72 will accommodate those tolerances in the post positioning.
While the panel means 26 of FIG. 1 are flat and generally planar, many applications of the post and panel barrier exist which experience considerable variations in ambient temperature and where spacing tolerances cannot be easily maintained. Variations in ambient temperature may lead to creation of significant compressive stresses in the panel means 26 and in the posts 22 which support particular panel means 26 when the panels are planar. Thermally induced expansions and contraction of the panel means 26 can lead to cracking of the panel means 26 unless somanar. Thermally induced expansions and contraction of the panel means 26 can lead to cracking of the panel means 26 unless some arrangement is established to relieve those thermally induced expansions and contractions. One arrangement of accommodating such thermally induced length variations is use of the joint packing material 72 described above in connection with FIG. 7. Another arrangement, and the most preferred embodiment of this invention, for accommodating these thermal expansions as well as for avoiding critical spacing problems is use of a folded panel means 74, as illustrated in FIG. 9.
The folded panel means 74 is supported in part by posts 22 which are the same in all material respects to those discussed above. The most preferred cross-sectional arrangement of the post is, however, illustrated in FIG. 11. The folded panel means 74 is similar to the panel means 26 discussed in connection with FIG. 1 in that it has shaped edges 28, 30 (FIG. 11) which conform to and are received by grooves provided in the sides of the wall posts 22. In addition to these features, however, each folded panel means 74 (FIG. 9) is provided with at least one hinged connection 76 positioned between the side edges 28, 30 and preferably positioned at approximately the center of the folded panel means 74. The hinged connection 76 is essentially parallel to the grooves in the posts 22 and the associated side edges 28, 30 of the folded panel means 74. In this manner, the hinged connection 76 permits the folded panel means 74 to flex in a direction perpendicular to the plane extending between adjacent posts 22.
This flexion capability provides significant advantages to the post and panel barrier illustrated. For example, thermally induced linear expansions and contractions of the wall panel 74 are accommodated by increased or decreased offset distances measured between the hinged connection 76 and the plane connecting adjacent posts 22. The offset provides a further benefit by increasing the front-to-back base thickness of the wall itself to resist toppling in response to wind pressures exerted on the face thereof. Another advantage of the folded panel means 74 resides in its ability to accomodate much greater tolerance in the spacing between adjacent posts. More particularly, the spacing between adjacent posts can be accommodated by increased or decreased offset in the folded panel means 74. The folded panel means 74 also allows the panel to be attached to posts without sliding panels down between posts 22. For example, the panel is folded while it is attached to one post and then unfolded sufficiently to attach with the next post. If desired, multiple hinged connections 76 may be provided in each panel means 74.
The folded panel means 74 includes a first panel section 78 and a second panel section 80 (FIG. 10). The first panel section 78 is preferably provided with a bullnose adjacent the post 22. Similarly, the second panel portion 80 has a bullnose adjacent the groove of post 22'. The post 22' is adjacent to the opposite side edge of the folded panel means 74. The hinged connection 76 between adjacent panel sections 78, 80 preferably includes a bullnose 82 and conformingly shaped groove 84. The bullnose 82 may be provided on one of the two panel sections 78, 80 with the conformingly shaped groove 84 being provided on the other of the two panel sections 78, 80.
A flexible tensile connection means is provided between the panel portions 78, 80 at the hinge line 76 as described above in connection with the attachment of the panel assemblies 78 to the associated posts 22.
When the folded panel means 74 is used on a surface environment having substantial frost movement, each post 22 is supported by a foundation 90 (FIG. 12) which extends below the frost line. Accordingly the posts 22 are vertically fixed and do not move with frost heaves.
In some application it may be desirable to provide a foundation 92 under the hinged connection 76. Here again the foundation 92 would extend below the frost line. With this arrangement the folded panel assembly 74 is clearly grounded against vertical movements inducted by frost. It should however, be noted that even without a foundation 92 under the hinged connection 76 the folded panel assembly 74 is grounded.
More particularly, the panel 78 cannot rotate in its plane relative to the post 22 since the tensile connectors prevent such rotation. Moreover the attachment of the panel 78 to the panel 80 physically prevents such rotation and the tensile connectors are that hinged connection 76 further prevent the relative rotation. Thus, when the panel means 74 rests on the post foundations 90, there really is no need for the intermediate foundation 92.
In situations where the panel means 74 can be permitted to move vertically with frost induced surface movements (FIG. 13) the panel means 74 is provided with a cut-out 94 at the bottom corner on each side edge 28, 30. Each cut-out extends laterally from the corresponding side edge 28, 30 by a distance sufficient to clear the post foundation 90. In addition, each cut-out 94 extends vertically above the post foundation 90 by a distance sufficient to mechanically decouple the vertical panel movement from the post. The unconfined length of the tensile connectors will permit this vertical flexibility.
In order to seal the privacy barrier, a compressible sealing material 96 is positioned in the cut-out 94. Accordingly, the opening at the cut-out is prevented from providing a path for transmission of sight, sound, environmental radiation and the like.
When it becomes necessary to erect the wall in a region where the underlying ground contour 86 (FIG. 14) is not level, then adjacent folded wall panel means 74, 74' extending from opposite sides of a post 22' are vertically offset. This vertical offset is effected by using the predetermined spacing between the pairs of channels 62 (see FIG. 2). Accordingly, (see FIG. 14), the panel means 74' may be positioned at a higher elevation on the post 22' than the panel means 74. This arrangement creates a stepwise increase in elevation of the panel means 74 as the wall traverses an uneven or inclined ground surface. In some areas the ground contour may require more frequent elevation changes (e.g. where it is steep) or esthetics may require more gradual steps. In these situations, additional vertical offsets may be made at the hinged connection of folded panel means, as shown at 74".
It will now be apparent to those skilled in the art that a new improved post and panel barrier structure has been described which overcomes the problems discussed above in connection with the prior art. Mod panel barrier structure has been described which overcomes the problems discussed above in connection with the prior art. Moreover, it will be apparent to those skilled in the art that numerous modifications, variations, substitutions and equivalents exist for various features of the invention as described in the foregoing specification. Accordingly, it is expressly intended that all such modifications, variations, substitutions and equivalents which fall within the spirit and scope of the appended claims, be embraced thereby. | A post and panel barrier system employs posts which are contoured to provide a constant maximum bending stress for anticipated wind pressure distributions. Posts and associated panel assemblies permit adjacent panels to meet at angles ranging from 0° to 360°. Panel assemblies used in the barrier system may be folded so that thermal movement and spacing tolerances are automatically compensated. Posts and panels may be decoupled to allow relative vertical displacements. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an improvement of cooling of a steel strip which has been cooled through a cooling zone in a continuous heat treating line, in particular, of final cooling of the strip by immersing in cooling water in a cooling tank.
2. Related Art Statement
There has been heretofore employed such method of cooling the steel strip by continuously passing through cooling water in a cooling tank for finally cooling the strip in the continuous heat treating line such as a continuous annealing line.
The cooling tank used for cooling the steel strip is provided with a sensor for detecting temperature of cooling water, a pump for supplying cooling water and a temperature controller and arranged such that the strip is cooled to a predetermined temperature during immersing in the cooling water in the cooling tank, while the cooling water is heated by taking the heat energy of the strip so as to be recovered in the form of hot water. Such steel strip cooling method is described, for example, in Japanese Patent Application Publication No. 11,933/57.
There has been however known that when the steel strip having a high temperature is cooled by immersing in cooling water in the cooling tank, the surface of the steel strip is often dirtied with foreign substances such as dirty suspensions or the like in the cooling water.
Furthermore, it has been known that the tendency of dirt adhesion on the surface of the steel strip becomes higher as in particular the temperature of the steel strip at the inlet of the cooling tank is higher and the amount of steel strip to be cooled in the cooling tank is greater.
It has been found that the surface of the steel strip is dirtied as a result in that in case of the steel strip still having a high temperature at the inlet of the cooling tank after cooling through the cooling zone in the heat treating line, the strip can not be sufficiently cooled with the cooling water in the cooling tank by the time of contacting with a first sink-roll so that a water film interposed between the surface of the sink-roll and the surface of the strip which is wound around the sink-roll is evaporated by the heat of the strip having a high temperature to deposit dirty suspensions included in the water on the surface of the strip.
Accordingly, in order to reduce the temperature of the steel strip at the time of winding the strip around the sink-roll, some methods have been proposed such that the steel strip is sufficiently cooled through the cooling zone of the heat treating line to fall the temperature of the strip at the inlet of the cooling tank or the cooling tank is made larger to increased the distance from the surface of cooling water to the sink-roll so as to cool the strip sufficiently with cooling water until the strip reaches the first sink-roll.
Such methods however have disadvantages that in case of reducing the temperature of the steel strip at the inlet of the cooling tank, not only the heat energy of the strip can not be recovered by the cooling water, but also the electric opower consumed in cooling the strip through the cooling zone arranged before the cooling tank is increased and in case of using the larger cooling tank, the cost of equipment becomes higher.
An object of the present invention is to provide a method and an apparatus of finally cooling a steel strip capable of preventing dirts from adhering to the surface of the strip without the above mentioned disadvantages.
Another object of the invention is to provide a method and an apparatus of cooling a steel strip capable of using a smaller cooling tank.
A further object of the present invention is to provide a method and an apparatus of effectively cooling a steel strip having a higher temperature at the inlet of the cooling tank to substantially reduce the power consumed in cooling the steel strip in the cooling zone of the continuous heat treating line.
According to an aspect of the present invention, a method of cooling a steel strip which has been cooled through a cooling zone in a continuous heat treating line comprises steps of immersing the strip in cooling water through around one or more sink-rolls in a cooling tank and injecting cooling water jets to the strip from injection nozzles arranged in the cooling water until the immersed strip reach the first one of the sink-rolls, thereby to cool the strip to a temperature for preventing evaporation of a water film interposed between the surface of the first sink-roll and the surface of the strip wound around the first sink-roll.
In a preferable embodiment of the invention, the injection of water jets from the injection nozzles may be controlled in accordance with the following formula: ##EQU1## here, l is the length of the portion of a steel strip cooled by water jets injected from injection nozzles (m)
Ts is the temperature of the steel strip at the inlet of the cooling tank (°C.)
Tw is the temperature of cooling water (°C.)
Cp is the specific heat of the steel strip (Kcal/kg°C.)
v is the feed speed of the steel strip (m/hr)
d is the thickness of the steel strip (m)
α is the coefficient of heat transfer (8,500˜10,500 Kcal/m 2 hr°C.)
ρ is the density of the steel strip (kg/m 3 )
According to another aspect of the present invention, an apparatus for cooling a steel strip which has been cooled through a cooling zone in a continuous heat treating line comprises a cooling tank containing cooling water, one or more sink-rolls arranged in the cooling water to guide the steel strip in the cooling tank, a guide roll provided at the inlet of the cooling tank for guiding the steel strip from the outlet of the cooling zone to the first one of the sink-rolls in the cooling water, a plurality of injection nozzles arranged along a passage of the steel strip in the cooling water to inject cooling water jets against the surfaces of the steel strip over the distance from the surface of the cooling water to the first sink-roll and means for supplying cooling water to the injection nozzles.
In a preferable embodiment of the invention, the apparatus further comprises a controller for controlling the temperature of the cooling water (Tw) and/or the steel strip (Ts) at the inlet of the cooling tank in accordance with the following formula:
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the present invention will appear more fully as the following description of illustrative embodiments proceeds in view of the drawings, in which:
FIG. 1 is a diagrammatic view of an embodiment of the invention;
FIG. 2 is a graph showing a condition of dirt adhesion;
FIG. 3 is a graph showing the relation between the coefficient of heat transfer and the follow rate of the injected cooling water;
FIGS. 4, 5 and 6 are diagrammatic views of another embodiments of the invention;
FIG. 7 is a graph showing the dead zone of dirt adhesion; and
FIG. 8 is a graph showing power consumed in cooling.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an embodiment of an apparatus for cooling the steel strip according to the invention. In FIG. 1, a cooling water tank 1 is provided with a sink-roll 2 arranged in the cooling water to guide a steel strip 7 passing through the cooling water from an inlet guide roll 20 at the inlet of the cooling tank to an outlet guide roll 21.
There is a sensor 3 on the wall of the cooling tank 1 for detecting the temperature of the cooling water. The sensor 3 is connected to a controller 4 for controlling the temperature of the cooling water, which controller supplies an output signal to a pump 5 when the temperature of the cooling water exceeds a predetermined temperature to supply cooling water to the cooling tank 1 through a cooling water supply pipe 8 while to overflow hot water from the cooling tank through an overflow pipe 6.
In the water tank 1, a plurality of injection nozzles 9 are arranged along a passage of the steel strip between the surface of the cooling water and the sink-roll 2 to inject cooling water jets against the surfaces of the steel strip in the cooling water. The injection nozzles 9 are connected to a pump 10 provided at a supply pipe connected for circulating the cooling water in the cooling tank 1.
In order to recognize cooling conditions in case of cooling steel strip 7 by immersing in the cooling water in a tank 1, the following experiments are conducted.
Each of steel strips having different thickness from each other is provided with a thermocouple and heated at a temperature on the order of 200° to 300° C. and then immersed in the cooling water in the tank 1. Table 1 shows results obtained in case of cooling by simply immersing the heated steel strips in the cooling water in the tank and Table 2 shows results obtained in case of cooling by injecting cooling water jets to the immersed steel strips from injection nozzles arranged in the cooling water.
TABLE 1______________________________________ (mm)steel stripThickness of (°C.)steel stripTemperature of (°C.)cooling waterTemperature ##STR1##______________________________________0.5 200 80 4,800 250 80 5,3001.0 200 75 5,450 200 85 4,8501.5 300 90 5,050 250 85 5,100 200 85 4,950 mean coeffi- 5,000 cient of heat transfer α.sub.1______________________________________
TABLE 2______________________________________ (mm)steel stripThickness of (°C.)steel stripTemperature of (°C.)cooling waterTemperature ##STR2##______________________________________0.5 200 80 10,100 250 75 9,7001.0 200 80 8,500 200 90 8,3001.5 300 85 9,800 250 80 10,500 200 85 9,600 mean coeffi- 9,500 cient of heat transfer α.sub.2______________________________________
It will be seen from the Table 1 and Table 2 that in case of cooling by simply immersing in the cooling water in the tank, a mean coefficient of heat transfer ρ 1 becomes about 5,000 (Kcal/m 2 hr°C.) and in case of cooling by use of immersed injection nozzles, a mean coefficient of heat transfer ρ 2 becomes about 9,500 (Kcal/m 2 hr°C.) irrespective of thickness of the steel strips and the temperature of the cooling water.
It will be seen from the above described results that the case of cooling by injecting cooling water jets to the immersed steel strip can significantly improve the coefficiency of heat transfer as compared with the case of cooling by simply immersing in the cooling water.
Accordingly, when the steel strip 7 having a high temperature is cooled by immersing in the cooling water in the tank 1, the steel strip can be quickly cooled by injecting cooling water jets to the steel strip through immersed injection nozzles.
The cooling water to be injected through the immersed injection nozzle 9 may be preferably controlled to satisfy the following conditions.
FIG. 2 is a graph showing the state of dirts adhered to the surface of the steel strip which is immersed at an inlet temperature Ts within 200° to 300° C. in the cooling water having a temperature Tw within 70° to 90° C. It will be seen from the graph that the dirts are adhered to the surface of the strip when the strip having a temperature Ts' at or higher than about 120° C. contacts the first sink-roll irrespective of the product of the speed of the steel strip (v/60) and the thickness of the steel strip (d×10 3 ). The temperature Ts' of the steel strip when the later reaches the first sink-roll 2 is represented by the following formula. ##EQU3## here, Ts is the inlet temperature of a steel strip (°C.)
Ts' is the temperature of the steel strip when the later reaches the first sink-roll (°C.)
Tw is the temperature of cooling water (°C.)
Cp is the specific heat of the steel strip (Kcal/kg°C.)
l is the length of the portion of the steel strip cooled by the water jets injected from the injection nozzles (m)
v is the speed of the steel strip (m/hr)
d is the thickness of the steel strip (m)
ρ is the density of the steel strip (kg/m 3 )
α is the coefficient of heat transfer (8,500˜10,500 Kcal/m 2 hr°C.)
Since the dirts adhesion on the surface of the steel strip can be prevented by controlling the cooling temperature of the steel strip so as to satisfy a condition of Ts'≦120° C.
The formula (1) can be written as follows: ##EQU4##
The formula (2) can be rewritten as follows: ##EQU5## As the result of the experiments, it is found that the mean coefficient heat transfer α is 95,000 (Kcal/m 2 hr°C.) and the density of the steel strip is 7,850. These values are substituted in the formula (3) and the following formula is given. ##EQU6## Accordingly, the cooling of the steel strip is controlled so as to satisfy the formula (4) by selecting the temperature of cooling water Tw°C. and the inlet temperature of the steel strip Ts in correspond to the product of the speed of the steel strip (v) and the thickness of the steel strip (d).
The flow rate (w) of the cooling water jets injected through the injection nozzles 9 is more than 1 m 3 /min.m 2 and the injection pressure is 3 to 5 kg/m 2 .
FIG. 3 is a graph showing the relation between the injection flow rate (w) and the coefficient of heat transfer (α 2 ). It will be seen from the graph that the coefficient of heat transfer (α 2 ) can be increased on the order of 9,000 to 10,000 Kcal/m 2 hr°C. when the injection flow rate (w) is increased to one or more m 3 /min.m 2 . However, even if the injection flow rate is further increased, the coefficient of heat transfer does not substantially exceed the above value, while the power consumed in injecting the cooling water is increased so that any remarkable effect could not be expected. It is therefore desirable that the injection flow rate (w) is controlled in a range of 1 to 2 m 3 /min.m 2 .
It will be described some embodiments of controlling for cooling a steel strip.
FIG. 4 shows an embodiment for cooling the steel strip 7 by controlling cooling water injected from the injection nozzles 9. A temperature of the cooling water (Tw) to be injected from immersed injection nozzles 9 in a cooling tank 1 is detected by means of a temperature sensor 11. The detected temperature (Tw) of cooling water is used together with the predetermined speed (v) and thickness (d) of steel strip to operate a central processing unit 12 according to the above formula (4) to determine a temperature of steel strip (Ts) at the inlet of the cooling tank. This calculated inlet temperature of steel strip is transmitted to a temperature controller 13 and compared with an actual inlet temperature of steel strip detected by means of a steel strip temperature sensor 14. An output signal from the temperature controller 13 is used to control a cooling zone 16 so as to limit the upper limit of the actual inlet temperature of steel strip in respect to the calculated inlet temperature.
FIG. 5 shows an embodiment for controlling a temperature (Tw) of cooling water to be injected from the injection nozzles 9. In this embodiment, there is arranged a heat exchanger 17 at the discharge side of the immersed injection pump 10 and a regulating valve 19 for controlling a flow rate of cooling water supplied to the heat exchanger 17. In this case, the inlet temperature of steel strip (Ts) and/or the temperature of cooling water (Tw) is determined and controlled by the central processing unit 12 which is operated according to the above formula (4) with the predetermined speed (v) and thickness (d) of the steel strip.
FIG. 6 shows another embodiment comprising two cooling tanks 1 and 20. In this embodiment, a temperature of cooling water in the second cooling tank 20 is controlled such that a target temperature is obtained by passing the steel strip 7 through both of the first cooling tank 1 and the second cooling tank 20. The cooling water in the second cooling tank 20 overflows into the first cooling tank 1 and the water in the tank 1 is overflowed through a discharge pipe 6 to be recovered as hot water.
EXAMPLE
It will be described a typical example of the invention referring to the embodiment shown in FIG. 4. A steel strip having a thickness of 0.5 to 1.5 mm and a width of 900 to 1,400 mm was finally cooled by injecting cooling water jets from the injection nozzles arranged in the cooling water. The temperature of the cooling water (Tw) was controlled at 80° C. and the length of the steel strip subjected to the cooling water jets (l) was 1.2 meters. The speed of steel strip (v/60) m/min multiplied by the strip thickness (d×10 3 ) mm was controlled to two hundred and fifty. The temperature of the steel strip was reduced through the cooling zone 16 from 350° C. to 270° C. at the inlet of the cooling tank. As a result of a macroscopic test, there was no dirt on the surface of the steel strip after final cooling.
While, for the purpose of comparing the steel strip was cooled by a conventional immersing manner under the same condition as the above.
FIG. 7 is a graph showing the dead zones of dirt adhesion according to the present invention and the conventional manner obtained as a result of the above comparing tests.
It was found from the comparing tests that in order to prevent the dirts from adhering to the surface of the strip, the temperature of the steel strip to be cooled by the conventional manner must be reduced through the cooling zone 16 from 350° C. to 168° C., while the temperature of the steel strip to be cooled according to the present invention is sufficient to reduce from 350° C. to 270° C. through the cooling zone 16.
It will be seen from FIG. 8 that in accordance with the invention the amount of power consumed in the cooling zone 16 is remarkably reduced and the total amount of power included the power consumed in the injection pump is about 0.7 KWH/T so that the cooling cost can be significantly reduced. | Disclosed is an improvement of final cooling of the steel strip by immersing in cooling water, which strip has been cooled through a cooling zone in a continuous heat treating line. The improvement is achieved by injecting cooling water to the surface of the immersed strip to rapidly cool the strip to a predetermined temperature until the strip reaches the first sink-roll and resulted in that any dirt adhesion on the surface of the strip caused by contacting with the first sink-roll is prevented without increment of cooling cost. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to materials for converting microwave energy into thermal energy, and further to microwave cooking receptacles which brown and sear food by using materials of this type. In particular, this invention relates to a compound made up of a high impedance soft magnetic material and other materials, and which has improved microwave conversion properties and lower cost, and to cookware made from the compound. Examples of suitable high impedance soft magnetic materials include ferrites and soft magnetic iron powder. Although the specific example given below uses iron oxide, those skilled in the art will appreciate that iron powder could be substituted for the purpose of even further lowering the cost of the material.
2. Description of the Related Art
Compounds of iron or iron oxide have been known since the beginning of the "iron age." More recently, it has been proposed to use a ferrite coating on a disposable container to convert microwave energy to heat in order to improve the browning, crisping, or searing properties of the container. Such a coating is described, for example, in U.S. Pat. No. 5,079,398. While a heating effect is said to be achieved (370°-400° F. in less than about 5 minutes or 120°-140° F. within about three minutes), however, the time it taken to reach an adequate temperature is unacceptably slow and the coatings described therein are costly and difficult to manufacture and also relatively costly in comparison with the material and cookware structure of the present invention.
Both the present invention and the material described in U.S. Pat. No. 5,079,398 are directed to the same problem, namely that certain foods cooked in a microwave oven are, by their appearance, displeasing because the microwave cooking process does not produce a color and texture in the food similar to that produced by conventional cooking methods, i.e., microwave-cooked food often is not seared, browned, and crisp, and in addition the compound of the present invention can use ferrite as one of the elements of the compound, the similarities essentially end there. The present invention provides a much more practical solution to the problem than did prior approaches, with better results such as improved durability and a lower heating time.
Although the present invention involves material which directly converts microwaves to thermal energy, those skilled in the art will appreciate by way of background that an alternative type of non-iron oxide based converting material can be fabricated from a plurality of resistive particles, each of which functions as an independent electrode so that adjacent pairs of particles form spark gaps. This alternative type of material is less relevant to the present invention than the direct conversion materials, and has the separate disadvantage that, when the resistive particles are irradiated with microwave energy, electric arcs form across the spark gaps, thereby producing an amount of thermal energy sufficient to sear and brown food. Converting materials of this type are disclosed, for example, in U.S. Pat. Nos. 4,496,815, 3,777,099, 3,731,037, and 3,701,872. In use, this type of converting material has at least the drawback that, in order for it to reach a temperature high enough for cooking, it has to be preheated in a microwave oven. This preheating step adds to the overall cooking time of the food, and thus undercuts what is generally accepted to be the primary advantage of microwave cooking--rapid food preparation.
Other types of converting materials such as semiconductor films do not require preheating (see, for example, U.S. Pat. Nos. 5,239,153, 4,970,360, 4,948,932, and 4,641,005), but such materials are in general primarily used in disposable cooking containers, and are not well suited for use in permanent cookware which requires washing and re-use on a daily basis.
It is clear from the foregoing discussion that converting materials presently in use in microwave cookware have drawbacks which limit, either in terms of convenience or economics, the everyday life of the consumer. A need therefore exists for an improved converting material which, when incorporated into the cooking surface of a microwave oven receptacle, will brown and sear food without realizing any of the disadvantages of existing microwave cookware.
SUMMARY OF THE INVENTION
It is a principal objective of the present invention to provide an improved material for converting microwave energy into thermal energy that is more economical to manufacture than known converting materials, including prior materials based on a composition of iron oxide.
It a second objective of the present invention to provide an improved material that is not only economical to manufacture but which has a composition that can be altered to achieve a desired temperature.
It is a third objective of the present invention to provide an improved material having the aforementioned properties which is encapsulated in a protective polymer coating for making the material impervious to moisture, and yet which is flexible and thus resistant to cracking, washable and reusable.
It is a fourth objective of the present invention to provide an improved microwave cooking receptacle, intended for permanent everyday use, which incorporates into its cooking surface a converting material having all of the aforementioned properties.
It is a fifth objective of the present invention to provide an improved microwave cooking receptacle which, when irradiated with microwave energy, can cook food without having to be preheated.
The foregoing and other objectives of the invention are achieved by providing a converting material which is made of a composition which includes a predetermined percentage of iron oxide, and which enables the converting material to be more economically manufactured as compared with known converting materials. In particular, the present invention provides a material for converting microwave energy to thermal energy which is made up of 50-70% iron oxide and a combination of two or more additives, and further mixed with water, calcium carbonate, aluminum silicate, a resin polymer, a rubber polymer, ethylene glycol, and mineral spirits.
In practice, the converting material converts microwave energy into thermal energy according to the principle of induction heating: Microwave energy impinging on the converting material creates eddy currents which generate an amount of thermal energy which depends in part on the percentage of iron oxide in the converting material.
The microwave cooking receptacle of the present invention includes a layer containing the converting material of the present invention interposed between a heat-absorbing layer and a heat-insulating layer. When irradiated with microwave energy, the converting layer generates heat which migrates to an upper surface of the heat-absorbing layer to raise the temperature of that upper surface to a level sufficient to brown and sear food thereon. Because the amount of thermal energy generated by the converting layer is proportional to the percentage of iron oxide contained in the composition, the maximum temperature of the cooking surface may be adjusted by adjusting the percentage of iron oxide in the converting layer.
Because the converting layer is enshrouded in a protective polymer coating, the cooking receptacle of the present invention is well suited for washing, which makes it ideal for everyday use. Moreover, the use of the above-described combination of materials in its converting layer, as opposed to other converting materials known in the prior art, enables the cooking receptacle of the present invention to cook food without having to be preheated.
BRIEF DESCRIPTION OF THE DRAWINGS
The sole FIGURE is a cross-sectional view of a microwave cooking receptacle made from the converting material of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is, in one respect, a material for converting microwave energy into thermal energy and, in another respect, a microwave cooking receptacle fabricated from this converting material.
The converting material of the present invention is made of a composition which includes a predetermined percentage of iron oxide coupled with at least two additives. Applicant has found that an iron oxide composition of between 50% and 70% provides the best performance.
The iron oxide in the composition is combined with other components including water, calcium carbonate, aluminum silicate ethylene glycol, and mineral spirits. The total mixture is then encapsulated in a resin polymer coating and a rubber polymer coating, both of which function to protect the converting material against moisture in order to provide an improved material which converts microwave energy into thermal energy according to the principle of induction heating: Microwave energy impinging on the converting material induces eddy currents in the material. The aggregate effect of these eddy currents is to produce an amount of thermal energy, and thus a converting material temperature, which is proportional to the percentage of iron oxide contained in the material.
The microwave cooking receptacle of the present invention may assume any size or shape desired. For example, the cooking receptacle may have the size and shape of a casserole dish, a sauce pan, a baking dish, or any number of cooking containers.
The sole FIGURE shows a cross-sectional view of the cooking receptacle 10 of the present invention in the shape of a baking dish. The receptacle includes a base 20 and a curved retaining wall 30 circumscribing the base. The base is fabricated from at least three layers. The first layer 1 functions as a heat-absorbing layer. It is preferably made of aluminum, iron, or an alloy of aluminum or iron. Layer 1 contains an upper surface 5 for supporting food to be cooked. To improve the appearance and texture of the food cooked in the receptacle, surface 5 may be treated with a non-stick coating such as Teflon™.
The second layer 2 functions as a converting layer. It is made of a composition that includes the converting material of the present invention, as previously described. Converting layer 2 preferably has a surface area which is substantially equal to the surface area of heat-absorbing layer 1, so as to ensure that food resting on surface 5 is uniformly and thoroughly heated by the thermal energy generated by the converting material. Other arrangements of the converting layer, however, are possible. For example, the converting material may be arranged in a pattern of strips underneath metal layer 1.
The third layer 3, which may be made of the same material and be physically continuous with layer 30, functions as an RF and heat insulation layer. Layer 3 preferably is made of a high temperature resist material such as glass, ceramic, and plastic. A commercial material known as Bakelite™ may also be used.
In practice, food to be cooked is placed onto the upper layer of metal layer 1. The receptacle is then placed into an oven and irradiated with microwave energy. The converting layer in the receptacle converts this microwave energy into an amount of thermal energy proportional to the percentage of iron oxide contained in the converting layer. The thermal energy migrates through the heat-absorbing layer to heat the upper surface to a temperature sufficient to sear and brown the food. Because the amount of thermal energy produced by the converting layer depends on the percentage of iron oxide that it contains, the maximum cooking temperature of the cooking receptacle can be adjusted by adjusting the percentage of iron oxide in the converting layer.
In one example of the present invention, a cooking receptacle having a converting layer containing between 50% and 70% iron oxide was irradiated in a 600 W microwave oven. After 3 minutes exposure, the upper surface of the receptacle reached a temperature of 300° F. The converting material remained at this temperature for as long as the microwave energy continued to irradiate the material. This ability to remain at a maximum temperature regardless of how long it is exposed to microwave energy advantageously allows the cooking receptacle of the present invention to cook food without burning it.
The microwave cooking receptacle of the present invention in many ways outperforms cookware made from converting materials known in the prior art.
First, because it requires less iron oxide, the cooking receptacle of the present invention is more economical to manufacture than known cooking receptacles, which use ferrite-based or resistive particle-type converting materials that require special preparation prior to their incorporation.
Second, the cooking receptacle of the present invention can rapidly generate an amount of heat sufficient for cooking food without requiring preheating. The same cannot be said for many types of cooking receptacles known in the prior art.
Third, because its converting material is encapsulated in a protective polymer coating to form a single layer having a thickness of 1-3 mm, the cooking receptacle of the present invention eliminates the need for multiple coating steps during manufacture and yet is more durable than conventional materials, and thus can for example be subjected to repeated cleaning in a dishwasher, making it is well suited for everyday use. In contrast, many converting materials known in the prior art are not treated with a protective coating. As a result, cookware fabricated from prior art converting materials are susceptible to damage and deterioration from moisture, and thus are not well suited for everyday use.
Other modifications and variations to the invention will be apparent to those skilled in the art from the foregoing disclosure. Thus, while only certain embodiments of the invention have been specifically described herein, it will be apparent that numerous modifications may be made thereto without departing from the spirit and scope of the invention. | A material for converting microwave energy into thermal energy is made of a composition which includes a combination of iron oxide, a polymer coating, and at least the following compounds: calcium carbonate, water, aluminum silicate, ethylene glycol, and mineral spirits. The material performs the microwave to thermal conversion according to the principle of induction heating. A microwave cooking receptacle incorporates the converting material into its cooking surface for browning and searing food. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of Invention
[0002] The present invention involves use of a snubbing apparatus to drill open hole. More particularly, the present invention involves use of a snubbing apparatus to drill open hole in underbalanced and managed pressure situations.
[0003] 2. Related Art
[0004] Heretofore, various configurations of drilling rigs have been proposed. The basic purpose of all such rigs has been the same: to drill a hole (a well or wellbore) that taps into an oil or gas reservoir. Subsequently, crude oil and/or natural gas are extracted from the tapped reservoir and processed into usable forms, such as gasoline and heating oil.
[0005] In oil and gas operations, pipes or tubular members are usually run in or pulled out of a well using conventional drilling or workover rigs or a snubbing apparatus. Workover rigs are effectively small drilling rigs having a derrick and drawworks. Although less costly and easier to employ than full sized drilling rigs, workover units can still be quite costly. Snubbing units are generally smaller, easier to transport and less expensive than workover or drilling rigs. The term “snubbing unit” is an industry expression designating equipment used to raise or lower pipe and bottom hole assembly components in a wellbore through some form of packoff assembly, with wellbore pressure. Thus, snubbing units are often employed when working a pressurized well which requires that tubular members be forced into the wellbore.
[0006] Conventional snubbing units require some means for forcing a pipe or tools into a well until the imposed force is sufficient to overcome any lifting or ejecting force of the well pressure on the pipe. The forcing can be accomplished with wireline blocks and wire rope. Typically, the pipe or tools are forced through a stripper head or blowout preventer. The term “stripper head” includes rotating control heads or rotating blowout preventers or annular blow out preventer.
[0007] It is often desirable during snubbing operations to rotate the pipe or tubular member. Most snubbing units, however, do not provide a method for imposing torque on a held pipe or tubular member (e.g., the snubbing unit described in U.S. Pat. No. 4,085,796); other snubbing units do (e.g., the snubbing apparatus described in U.S. Pat. No. 5,746,276).
[0008] Generally, rigs can rotate a bit in one of three different ways. One way uses a rotary table and kelly. Alternatively, a topdrive device can be employed. A third possible way involves use of a downhole motor.
[0009] A rotary table and kelly system involves use of a rotating turntable that mates with a special flattened sided pipe (a kelly). A top drive, on the other hand, uses a “power swivel,” not a kelly, to rotate the drill stem and bit. The third alternative, downhole motors, does not rotate the pipe; instead, it rotates the drill bit, and is powered by a drilling fluid, most often.
[0010] A “packoff assembly” has previously been mentioned. To “pack off” is to place a packer or other elastomeric equipment in or above the wellbore and to activate it so that it forms a seal between the drillstring or tubing and the casing. Often, the packoff assembly comprises a blowout preventer (BOP). A BOP is equipment that prevents the escape of pressure either in the annular space between the casing and drill pipe, or from the drill pipe itself when used in conjunction with some form of internal drillstring valve, during drilling and completion operations.
[0011] “Casing” is steel pipe placed (and then generally cemented) in a well as drilling progresses to prevent the walls of the wellbore from caving in during drilling, and to provide a conduit to the surface. An open hole, on the other hand, is a wellbore having no casing.
[0012] Conventionally, drilling is carried out in an overbalanced condition, a condition in which fluid pressure in a wellbore is greater than fluid pressure in the formation surrounding the wellbore. Mud (a fluid circulated in a well) is used in conventional drilling to ensure that hydrocarbons are not produced during drilling, which can be unsafe. In underbalanced drilling (UBD), on the other hand, fluid pressure in a wellbore is less than fluid pressure in the surrounding formation. A primary value of underbalanced drilling is to reduce formation damage. Negative or differential pressure between the formation and a wellbore also enhances fluid and gas flow from the reservoir by reducing the damaging effects encountered when using fluids. Increased penetration rates are also often observed in wells drilled underbalanced. In UBD, hydrocarbon production is assumed, and planned for. Underbalanced drilling is, however, initially more costly than overbalanced drilling, and to maximize benefits extreme care must be taken to keep drilling and completion operations underbalanced at all times.
[0013] “Managed pressure drilling” involves precise control of the annular fluid pressure within a wellbore. Managed pressure drilling (MPD) is a technique or tool which will, in comparison with conventional drilling, mitigate some of the risks and costs associated with drilling wells with narrow downhole environmental limits by proactively managing (or “walking the line” with regard to) the annular hydraulic pressure vs. formation or reservoir pressure profile. The purpose of MPD is both to ascertain the downhole pressure environmental limits and to manage the annular hydraulic pressure profile to fill that window. In MPD, hydrocarbon production is not planned for or is limited in volume.
[0014] With regard to both UBD and MPD, the associated wellbore is under pressure (putting aside hydrocarbon production), and therefore pressure in the wellbore must be handled appropriately.
[0015] U.S. Pat. Nos. 5,029,642 and 5,180,012 disclose a method and apparatus for the running of various tools and devices used to service oil and gas wells in combination with coiled tubing apparatus that permits the application of a sudden downward force of predetermined magnitude. These patents teach away from use of a snubbing apparatus to retrieve stuck valves, as coil tubing apparatus can (according to these patents) provide a much greater pulling capacity than a wireline saving the use of the much more expensive standby work-over rig snubbing apparatus necessary in the event the wireline apparatus cannot retrieve a stuck valve.
[0016] U.S. Pat. Nos. 5,662,170 and 5,842,528 (assigned to Baker Hughes) disclose a method and assembly for completing a well. These patents do mention open hole drilling and completion, and that snubbing units are less expensive; however, they do not teach or suggest use of snubbing units for drilling open hole: “In order to minimize cost [of drilling and completion], several techniques have been employed with varying degrees of success. One technique has been to drill and case the well, and then immobilize the drilling rig. A replacement rig is then utilized to complete the well. The replacement rig may vary from a snubbing apparatus, coiled tubing apparatus, work over rig using smaller inner diameter pipe, and in some cases wire line. Thus, rather than completing the well with the more expensive rig, a less expensive rig is utilized.” (column 2 , lines 22 - 30 ) These passages are not enough to teach or suggest using a snubbing apparatus for drilling open hole.
[0017] U.S. Pat. No. 6,065,550 discloses a method and system of drilling multiple radial wells using underbalanced drilling. FIG. 11 of this patent illustrates a flow diagram for underbalanced drilling or completing of multilateral wells off of a principal wellbore utilizing the two string technique where there is a completed multilateral well that is producing and a multilateral well that is producing while drilling is ongoing utilizing drill pipe and a snubbing apparatus as part of the system. However, from the disclosure it appears that the snubbing apparatus is not being used to drill, but only being used in the traditional sense to control pressure in an underbalanced situation.
[0018] U.S. Pat. No. 6,209,663 discloses apparatus and methods for a deployment valve used with an underbalanced drilling system to enhance the advantages of underbalanced drilling. The underbalanced drilling system may typically comprise elements such as a rotating blow out preventer and drilling recovery system. The deployment valve is positioned in a tubular string, such as casing, at a well bore depth at or preferably substantially below the string light point of the drilling string. This patent teaches away from using a snubbing apparatus for removing drill string, and does not disclose or suggest using a snubbing apparatus for drilling open hole. After discussing some of the problems of UBD, the patent states “Another very effective and safe practice is that of providing a snubbing apparatus for removing the drilling string. However, the snubbing apparatus takes considerable time to rig up, requires considerable additional time while tripping the well, and then requires considerable additional time to rig down. Thus, the cost of tripping the drill string can be quite considerable due to the rig time costs and snubbing apparatus costs. Additional tripping of the well may also be necessary and again require the snubbing apparatus. This procedure then, while effective and safe, increases drilling costs considerably.”
[0019] U.S. Pat. No. 6,367,566 discloses a system and method that permits control of down hole fluid pressures during underbalanced drilling, tripping of the drill string, and well completion to substantially avoid “killing” of the well and thereby damaging the producing formations in the well bore. The system and method utilizes separate and interconnected fluid pathways for introducing a downwardly flowing hydrodynamic control fluid through one fluid pathway and for removing through the other fluid pathway a commingled fluid formed by mixing of the hydrodynamic control fluid and the well bore fluids flowing upwardly in the well bore. This patent teaches away from using a snubbing apparatus, and does not teach or suggest using a snubbing apparatus to drill open hole. The patent states “As an alternative to killing the well with a heavy well-bore fluid, the drill pipe, production tubing or other equipment may be stripped in or out of the well under high well-head pressure through a snubbing apparatus. This procedure is expensive and complicated. Furthermore, if the well is shut-in under high pressure while stripping pipe or equipment in or out of the well through a snubbing apparatus, the liquids at the bottom of the well bore may be injected into the formation adjacent to the well bore and adjacent to the hydraulic fractures. In the zones invaded by these bottom-hole well-bore liquids while stripping through the snubbing apparatus, the rock permeability to the formation fluids may be severely damaged as described above.”
[0020] U.S. Pat. Nos.6,394,184; 6,520,255; and 6,957,701 (assigned to ExxonMobil Upstream Research Company) disclose methods of, as well as apparatus and systems for, perforating and treating multiple intervals of one or more subterranean formations intersected by a wellbore by deploying within said wellbore a bottom-hole assembly (“BHA”) having a perforating device and a sealing mechanisms, wherein pressure communication is established between the portions of the wellbore above and below the sealing mechanism. These patents discuss snubbing, but not in terms of drilling using a snubbing apparatus. FIG. 10 of the patents illustrates in detail an embodiment of the invention where a jetting tool is used as the perforating device and jointed tubing is used to suspend the BHA in the wellbore. As the patent states, in this embodiment, jointed tubing is preferably used with a mechanical compression-set, re-settable packer since it can be readily actuated and de-actuated by vertical movement and/or rotation applied via the jointed tubing. Vertical movement and/or rotation is applied via the jointed tubing using a completion rig-assisted snubbing apparatus with the aid of a power swivel apparatus as the surface means for connection, installation, and removal of the jointed tubing into and out of the wellbore.
[0021] U.S. Pat. Nos. 6,457,540 and 6,745,855 disclose a method and system of drilling straight directional and multilateral wells utilizing hydraulic frictional controlled drilling, by providing concentric casing strings to define a plurality of annuli therebetween; injecting fluid down some of the annuli; returning the fluid up at least one annulus so that the return flow creates adequate hydraulic friction within the return annulus to control the return flow within the well. A snubbing unit is used for well control during trips out of the hole and to keep the well under control during the process. The snubbing units is considered a key component for being able to safely trip in and out of the wellbore during rotary drilling operations. The snubbing unit allows one to retrieve the drill bit out of the hole and yet maintain the pressure of the underbalanced well to keep the well as a live well. However, the snubbing unit is used only when the drilling or completion assembly is being tripped in and out of the hole. These passages do not teach or suggest using a snubbing unit for drilling open hole.
[0022] U.S. Pat. No. 6,755,261 (assigned to Varco I/P, Inc.) discloses methods and systems for varying fluid pressure in a circulation system while circulating a “kick” out of a wellbore drilled through a subterranean formation. While the patent does discuss open hole, the only mention of snubbing is in a boilerplate paragraph near the end, where it is stated that equipment used may also include conventional and known non-conventional equipment, including coiled tubing units or snubbing units.
[0023] Published US patent application 20040238177 discloses an arrangement and a method to control and regulate the bottom hole pressure in a well during subsea drilling at deep waters, involving adjustment of a liquid/gas interface level in a drilling riser up or down. The only mention of snubbing is in discussing the gas pressure in the riser being
DETAILED DESCRIPTION
[0024] In the following description, numerous details are set forth to provide an understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
[0025] All phrases, derivations, collocations and multiword expressions used herein, in particular in the claims that follow, are expressly not limited to nouns and verbs. It is apparent that meanings are not just expressed by nouns and verbs or single words. Languages use a variety of ways to express content. The existence of inventive concepts and the ways in which these are expressed varies in language-cultures. For example, many lexicalized compounds in Germanic languages are often expressed as adjective-noun combinations, noun-preposition-noun combinations or derivations in Romanic languages. The possibility to include phrases, derivations and collocations in the claims is essential for high-quality patents, making it possible to reduce expressions to their conceptual content, and all possible conceptual combinations of words that are compatible with such content (either within a language or across languages) are intended to be included in the used phrases.
[0026] The invention describes apparatus and methods of using same in drilling open hole in wellbores. The terms “well” and “wellbore” are used interchangeably herein, and may be any type of well, including, but not limited to, a producing well, a non-producing well, an experimental well, and exploratory well, and the like. Wellbores may be vertical, horizontal, some angle between vertical and horizontal, diverted or non-diverted, and combinations thereof, for example a vertical well with a non-vertical component. Although methods for drilling open hole have been improved over the years, there remains a need for improved designs, especially those that may operate in a variety of wellbore pressure situations without killing a well.
[0027] The methods and apparatus of the present invention may be employed in an underbalanced application or in a managed pressure application.
[0028] There are many reasons for using a snubbing unit instead of a conventional drilling rig, some of those reasons including: very low, causing the drill string to be “pipe heavy” at all times, excluding the need for snubbing equipment or “pipe light” inverted slips in the drilling operation.
[0029] Published US patent application 20050006098 generally relates to a method and an apparatus for stimulating the production of an existing well. The patent teaches away from the use of a snubbing apparatus for pressure control, and there is no teaching or suggestion of drilling with a snubbing apparatus. As a selective treatment assembly is urged toward the surface of the wellbore, a releasable mechanical connection fails, thereby allowing a plug assembly to separate from the selective treatment assembly and remain downhole in a polished bore receptacle (PBR) while the selective treatment assembly continues to be moved toward the surface of the wellbore. In this respect, the plug assembly separates and seals a treated portion of the wellbore below the PBR from an untreated portion of the wellbore above the PBR. Thereafter, the pressure in the untreated portion of the wellbore is bled down to 0 Psi, thereby allowing the jointed pipe connected to the selective treatment assembly to be removed without the use of a snubbing unit.
[0030] Published U.S. patent application 20050115713 discloses a wellbore junction including a first passage extending from a first opposite end to a second opposite end of the wellbore junction. A window is formed through a sidewall of the wellbore junction and provides fluid communication between the first passage and an exterior of the wellbore junction. Snubbing is mentioned discussing UBD as a possible implementation of the invention. A fluid loss control device such as a valve may be used in these embodiments, which permits a drill string to be tripped in and out of the branch wellbore while the wellbore is in an underbalanced condition, and without a need for killing the well or snubbing the drill string out of the well under pressure. There is no teaching or suggestion of using a snubbing apparatus to drill open hole.
[0031] U.S. Pat. No. 4,085,796 (assigned to Otis Engineering Corporation, Dallas, Tex.) describes snubbing units as well tubing handling systems employed in running and pulling well tubing under pressure, particularly, for well workover operations. The patent notes that one of the most vital factors in the operation of well snubbing units is the cost of servicing a well with the apparatus. Such cost is directly related to the time factor which is primarily affected by the speed of operation of the apparatus. In addition to the number of cycles required for the apparatus to run or pull a given length of well tubing, the actual weight which the apparatus can handle is an important factor. Usually, such apparatus is rented or leased on a time basis and the cost of operation is additionally affected by the cost of paying the wages of the operators. A still further element in the total expense of servicing a well is the length of time the well is shut down and, thus, not producing an income.
[0032] U.S. Pat. No. 4,649,777 discloses back-up power tongs for holding a tubular member, such as a drill pipe, against rotation of a connected tubular member, the back-up tongs comprising a body, having a center opening of sufficient size for the tubular member to pass therethrough, a slot communicating between the edge of the body and the center opening, and a cavity disposed within the body. A plurality of jaw members are disposed within the body around the perimeter of the center opening, each jaw member having a concave surface generally conforming to the curvature of the tubular member and facing the interior of the opening so as to be grippingly engageable with the tubular member. At least one cylinder assembly is disposed within the cavity and fixedly connected to one jaw member so as to extend or retract the jaw member on a radial path centered at the center of the tubular member.
[0033] U.S. Pat. Nos. 5,746,276 and 5,566,769 (assigned to Eckel Manufacturing, Odessa, Tex.), disclose a tool for rotating a tubular member passing through a slip assembly powered by a rotary table of a drilling rig. The patents state: “While snubbing operations have significant advantages compared to workover operations where the well is killed, a recognized disadvantage of a snubbing operation is that the workover string may become stuck in a wellbore. When this occurs, remedial operations to “unstick” the string can be very expensive and time consuming. In some instances, it is also desirable to rotate a work string during a conventional workover operation even when the well is killed. The patent describes improved techniques and equipment which allow rotation of a workover string during the snubbing or workover operations. More particularly, the tool allows for the rotation of the entire work string when making up or breaking apart a threaded joint at the well. While this patent appears to disclose means to rotate a workover string during snubbing, there is no teaching or suggestion of using a snubbing apparatus to drill open hole.
[0034] U.S. Pat. No. 6,640,939 discloses an improved snubbing unit including a snubbing unit base, a lifting assembly having a platform positioned above the base, a rotary table positioned on the snubbing unit, and a first slip assembly positioned on the rotary table. While this patent appears to disclose means for rotating a workover string during snubbing, there is no teaching or suggestion of drilling open hole with the snubbing apparatus.
[0035] Notwithstanding all of the advances made in the drilling art, some of which are discussed briefly above, it is a shortcoming and deficiency of the prior art that there has not heretofore been a quick and easy way to drill, especially in certain unconventional situations.
SUMMARY OF THE INVENTION
[0036] In accordance with the present invention, methods and apparatus are described that reduce or overcome problems in previously known methods and apparatus.
[0037] A first aspect of the invention are methods, one method comprising:
a) isolating or controlling downhole pressure in a wellbore; and b) drilling open hole while isolating or controlling the downhole pressure.
[0040] Methods of the invention include those methods wherein the drilling open hole while isolating or controlling of downhole pressure comprises using a push-pull component selected from a deployment valve, a snubbing unit, a well workover rig, a wireline push-pull unit, and combinations thereof. Certain methods of the invention include those wherein the drilling open hole comprises drilling in an underbalanced condition. Other methods of the invention are those wherein the drilling open hole comprises drilling in a managed pressure condition. Methods of the invention may include producing one or more materials from the well, and may further comprise processing the material or materials, wherein the materials may be any materials producible from a wellbore, including an open hole, and may comprise materials selected from hydrocarbons (including but not limited to hydrocarbon oils and hydrocarbon gases), dirt, water, brine, and the like, and combinations and mixtures thereof. Where the material comprises hydrocarbon oil and gas, and water, processing may include separating oil, gas and water, and may further include reinjecting one or more processed fluids downhole.
[0041] A second aspect of the invention are apparatus, one apparatus comprising:
a) a pressure control component strategically positionable in a wellbore to isolate or control downhole pressure while drilling open hole; b) the pressure control component comprising a rotational drive member effective to rotate a tubular member while drilling open hole.
[0044] Apparatus of the invention include those wherein the pressure control component is a push-pull unit selected from a snubbing unit, a workover rig, a wireline push-pull unit, and combinations thereof. Apparatus of the invention include those apparatus further comprising means for processing any material extracted from the wellbore, and apparatus wherein the pressure control component achieves an underbalanced situation in the wellbore. Certain apparatus of the invention are those apparatus in which the pressure control component achieves a managed pressure situation in the wellbore, or in an annulus. Apparatus of the invention include those apparatus comprising processing components, which may be selected from gas extracting components, dirt extracting components, and the like, and combinations thereof. Certain apparatus of the invention comprise separation units capable of separating oil, gas and water, and may further comprise processing units capable of reinjecting wellbore fluids downhole.
[0045] Another apparatus of the invention comprises:
a) a snubbing unit for drilling a well open hole in a surrounding geologic formation having a formation fluid pressure, the well having a well fluid pressure; and b) means for maintaining the well fluid pressure less than the formation fluid pressure.
[0048] Apparatus within this aspect of the invention include a surface system for processing any material extracted from the well, wherein system for processing may comprise any one or more of a gas extractor, an oil extractor, and a water extractor. The processing system may comprise a fluid reinjector for reinjecting fluid downhole. The apparatus may comprise means for maintaining the well in an underbalanced situation or in a managed pressure situation.
[0049] These and other features of the apparatus and methods of the invention will become more apparent upon review of the brief description of the drawings, the detailed description of the invention, and the claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] The manner in which the objectives of the invention and other desirable characteristics can be obtained is explained in the following description and attached drawings in which:
[0051] FIG. 1 is a schematic, partial block and partial longitudinal cross section view illustrating an embodiment of the present invention;
[0052] FIG. 2 is a schematic side elevation view, partially in cross section, with some parts broken away, illustrating a snubbing unit which may be used according to the teachings of the present invention;
[0053] FIG. 3 is a schematic side elevation view illustrating a snubbing stack incorporating some of the features of the present invention;
[0054] FIG. 4 is a graph depicting depth versus pressure profiles in underbalanced drilling (UBD); and
[0055] FIG. 5 is a schematic process flow diagram illustrating a surface processing system that may be employed in practicing the present invention.
[0056] It is to be noted, however, that the appended drawings are not to scale and illustrate only typical embodiments of this invention, and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. Identical reference numerals are used throughout the several views for like or similar elements.
[0057] a. Reduced rig/operational modifications for drilling programs requiring flammable drilling fluids/gases. Electrical/ignition sources are easily removed from the areas of operations during well planning operations.
[0058] b. Apparatus of the present invention are designed for pressure operations and allows tripping of pipe without killing the well. This is especially important on IADC level 4 and level 5 wells where flow rates and pressures can be extremely important.
[0059] c. Rig crews are for the most part trained and ready for operating in pressured conditions. Use of apparatus and methods of the present invention reduces or eliminates the cost of crew training and the fear factor for conventional rig crews.
[0060] d. A stand alone hydraulic snubbing unit may allow drilling operation without the cost and availability of a rig.
[0061] e. The footprint of systems incorporating apparatus of the invention is much smaller than that of a conventional rig modified for underbalanced drilling. This should prove effective on small platforms and on small land locations where space is critical.
[0062] f. Stack configurations incorporating apparatus of the invention may accommodate items such as core barrels and other bottom hole assembly systems.
[0063] g. Apparatus and methods of the invention provide an excellent system for underbalanced drilling and managed pressure drilling or coring.
[0064] h. When apparatus of the invention are used in conjunction with a full opening valve which is placed on the wellhead, the stack out becomes a lubricator for the bottom hole assembly. The valve functions as a shallow set deployment valve, an emergency blind ram, and it supplies a barrier upon rig up or rig down operations.
[0065] The methods of using apparatus of the invention and systems incorporating same provide for drilling a well open hole, including isolating the pressure downhole. Such isolation may be provided by a deployment valve.
[0066] Still further, the methods and apparatus of the invention and systems incorporating same may provide means for processing material removed from a well, including separating oil, gas, and other material (such as water, or dirt) and means for reinjecting fluid back into the well, however, the invention is not so limited; the ability to separate fluids at the surface is not required.
[0067] Referring now to the drawings, and more particularly to FIG. 1 , which is a schematic side elevation view, partially using blocks, and in partial cross section, of the major components of apparatus and methods of the present invention. In broad terms, the present invention comprises apparatus and methods for isolating pressure downhole or beneath some type of pressure control equipment, whether this is a stripping head, rotating control head or other type of pressure control component. The pressure control component of the inventive apparatus may be a snubbing unit. Alternatively, or in conjunction with a snubbing unit, the pressure control component may be (or include) a deployment valve placed in the wellbore. In the latter case, a deployment valve may be pulled or run into the wellbore to the point below where the drillpipe is still “heavy” in the well; there, pressure would be bled off above the valve so that pipe may be pulled out without formally “snubbing” the well.
[0068] Referring specifically to snubbing units, any type of snubbing unit—hydraulic, mechanical, combination thereof, or any other equivalent type, for that matter—may be used in embodiments of the present invention. “Snubbing”, a verb, is well known in the art, and generally means forcing a pipe into a well against pressure. As previously mentioned, snubbing units (i.e., apparatus that perform snubbing) are well known and readily available; apparatus of the invention may comprise any type of snubbing unit, and methods of using apparatus of the invention may use any type of snubbing unit to practice the present invention, although the invention is not limited to use of snubbing units for pressure control, as previously discussed.
[0069] Referring again to FIG. 1 , illustrated schematically therein is a pipe 4 being forced by a snubbing unit 2 into a well 6 . At the farthest end (distal end) of pipe 4 into well 6 is a bit 8 . Bit 8 is a cutting or boring element that drills well 6 into and through a formation 10 surrounding well 6 . Well 6 may also be called a wellbore. Ideally, hydrocarbon oil and/or gas will be tapped into by well 6 , and the hydrocarbon oil and/or gas can then be brought to the surface 12 for processing.
[0070] The instant invention involves the use of snubbing unit 2 to drill open hole. While snubbing units have previously been used in the art for their intended use (snubbing), the inventor herein is aware of no instance where a snubbing unit has been used to drill open hole in the underbalanced condition. Using a snubbing unit to drill open hole is an aspect of the present invention. An “open hole” is a well in which casing or a protective liner has not been set. Casing, illustrated in FIG. 1 by reference numeral 14 , is pipe placed (and generally cemented) in a hydrocarbon oil or gas-bearing well as drilling progresses to prevent the wall of well 6 from caving in. A portion of well 6 designated with reference numeral 16 in FIG. 1 has no casing; portion 16 is an open hole. Open hole drilling has no casing; the walls of the borehole are the substrate.
[0071] Referring still to FIG. 1 , snubbing unit 2 is capable of raising and lowering pipe 4 and bottom hole assembly (i.e., bit 8 ) into well 6 through some form of packoff assembly 18 . Packoff assemblies insure that a well is drilled correctly (i.e., having a proper flow course). A blowout preventer (BOP) is equipment installed at the surface at the top of well 6 (or possibly on the seafloor), which equipment prevents the escape of pressure during drilling and completion operations. A rotating control head (RCH), an annular BOP or a similar such packoff assembly structure 18 could also be employed at this location. Any and all of which manner of packoff assemblies 18 through which pipe could be manipulated by a snubbing unit according to the teachings of the present invention will readily occur to those skilled in the art. By way of illustration, a BOP is illustrated in block form at 18 in FIG. 1 .
[0072] For convenience in further description, well 6 will be said to contain hydrocarbon oil or gas or water having certain fluid pressure, while the surrounding formation 10 also has an associated fluid pressure. Underbalanced drilling involves the pressure of the fluid in well 6 being less than the pressure of formation 10 . Underbalanced drilling is well known to increase safety and productivity. See “Underbalanced Completions Improve Well Safety and Productivity,” by Tim Walker and Mark Hopman (World Oil, November 1995), which is hereby incorporated by reference herein. Apparatus and methods of the invention are especially ideal for drilling open hole in an underbalanced condition.
[0073] Yet another term frequently used in the art is “managed pressure drilling.” Managed pressure drilling, or MPD, as it is called, encompasses adaptive drilling techniques (e.g., use of backpressure, variable fluid density, fluid rheology, circulating friction, and/or annular fluid pressure profile) within a well. Further information regarding the techniques and advantages of MPD may be found in materials generated for the Managed Pressure Drilling Forum, Jan. 27-29, 2004, at the Moody Gardens Hotel and Conference Center in Galveston, Tex., which is hereby incorporated by reference herein. Apparatus and methods of the present invention are also especially ideal for open hole drilling in managed pressure situations.
[0074] FIG. 2 is a schematic side elevation view, partially in cross section, with some parts broken away, illustrating a snubbing unit which may be used according to the teachings of the present invention. Snubbing unit 2 may be any conventional snubbing unit, except that it is used to drill open hole, particularly in underbalanced and managed pressure situations in accordance with the teachings herein.
[0075] Snubbing unit 2 incorporates slip assemblies 24 . Snubbing unit 2 in FIG. 2 is illustrated positioned on a blowout preventer 26 and generally comprises a base 28 , basket support columns 30 , a basket 32 (with a basket railing 34 ), and a lifting assembly 36 . Lifting assembly 36 includes a lifting platform 38 supported by hydraulic cylinders 40 which raise and lower lifting platform 38 . Positioned atop lifting platform 38 is a rotary table 42 with a first (upper) slip assembly 44 connected thereto. Rotary table 42 may be any conventional torque generating device which may be positioned atop lifting assembly 36 . Many different types of rotary tables are well known in the drilling industry and could be applied in snubbing unit 2 , although the rotary table illustrated in FIG. 2 is hydraulically driven. Hydraulic fluid may be supplied to rotary table 42 through hydraulic hoses 46 and to slip assembly 44 through a conventional hydraulic swivel. Hydraulic swivel assemblies are well known in the art and one such hydraulic swivel assembly is available from Superior Manufacturing, Inc., located at 4225 Highway 90 East, Broussard, La., under the tradename Clincher Hydraulic Rotary Table, Model No. HRT-20B (although the model number may vary based upon the rotary table's size). Another suitable rotary table is available from Hydra Rig, located at 6000 Berry Street, Fort Worth, Tex. 76119.
[0076] The detailed insert of hydraulic swivel assembly 48 illustrated in FIG. 2 schematically illustrates how a conventional hydraulic swivel supplies fluid to slip assembly 44 . Hydraulic swivel assembly 48 allows a fixed hydraulic fluid line 50 to transfer fluid through a rotating hub 52 . While the main FIG. 2 illustration only illustrates a single fluid line 50 , the detailed insert more precisely illustrates line 50 divided into dual internal fluid lines 50 a and 50 b. Swivel assembly 48 includes a hydraulic swivel ring 54 which encircles rotating hub 52 , but is held stationary (by a structure hidden from view in FIG. 2 ) while rotating hub 52 is attached to rotary table 42 . Hydraulic swivel assembly 48 will further have two annular passages 56 and 58 formed at the junction of swivel ring 54 and rotating hub 52 . It should be understood that passages 56 and 58 are annular in the sense that they form a space completely encircling the circumference of rotating hub 52 . Because passage 56 is annular, passage 56 may maintain fluid communication between internal fluid lines 50 a and 60 throughout rotating hub 52 's entire range of rotation. Likewise, it can be seen that annular passage 58 maintains communication between internal hydraulic lines 50 b and 62 in the same manner. Seals 64 will ensure fluid does not escape from the point where swivel ring 54 mates with rotating hub 52 . Internal line 60 will typically be attached to an external line (not illustrated) as internal line 60 exits rotating hub 52 and that external line will connect to an inlet (not illustrated) of cylinders (not illustrated). As is well known in the art, line 50 a may direct fluid to the upper inlet on a cylinder (thus retracting the cylinder) while fluid line 50 b may direct fluid to the lower inlet on the cylinder (thus extending the cylinder). A second (lower) slip assembly 66 is illustrated positioned upon base 28 . It will be understood that all elements positioned along the center line of snubbing apparatus 2 will have a central aperture allowing a pipe or other tubular member 68 to pass therethrough. A cut-away section illustrates a tubular joint 70 connecting two successive tubular members 68 . A fuller description of snubbing units and their operation may be seen in references such as U.S. Pat. No. 4,085,796 to Council, which is incorporated herein by reference.
[0077] Conventional snubbing units generally include a power and a backup power tong. Additionally, an upper slip assembly may be positioned upon a swivel base which allows the slips to rotate when the tubular string rotates. In operation, the upper slip assembly will grip the tubular string and a lower slip assembly will release the tubular. of the snubbing unit could be designed to possibly impose torque on a tubular 68 . Many other variations of snubbing units are possible, and any and all of those variations are considered within the scope of the invention.
[0078] The inventor herein has found power tongs, a crane or gin pole package (which assists in picking up and lowering pipe), slip rams (in a BOP section) and a long riser or lubricator package, to be especially useful.
[0079] Power tongs have previously been described. A crane is a machine for manipulating heavy pieces of equipment, especially offshore. A gin-pole truck also lifts heavy equipment with hoisting equipment and a pole or an arrangement of poles. Slip rams have also been described. A riser is a pipe through which liquid may travel upward. A lubricator is a specially fabricated length of casing or tubing usually placed temporarily above a valve on top of the casing or tubing head. A lubricator allows a device such as a wireline to pass into the well. All of the terms used herein and the equipment associated with them are well known in the art and should be readily understood and appreciated by those skilled in the art.
[0080] Notwithstanding the particular makeup of a snubbing unit, the instant invention contemplates and covers using a snubbing unit to drill open hole in underbalanced situations, as well as in managed pressure situations.
[0081] Referring now to FIG. 3 , there is illustrated a snubbing stack 2 that may employ an apparatus of the invention. FIG. 3 illustrates a conventional 7- 1/16″ 5M CIW “U” Snubbing Stack. The depicted stack 2 includes a Shaffer Annular BOP 80 . Recognizing that the term ram denotes a closing or sealing component, stack 2 also comprises a blind ram 82 that when closed, forms a seal that has no pipe through it. Stack 2 also comprises stripper rams 84 that can perform sealing functions. Stack 2 also comprises safety rams 86 and “VARI VARI” 88 . Please note that elements in FIG. 3 are not illustrated to scale: for example, the mid placed “snubbing stack” in FIG. 3 is designated to be 48 feet long; the immediately adjacent elements to it ( 84 / 86 and 86 / 82 ) are each designated to be 44 inches long, although each is depicted as longer than the 48 foot section, mentioned above. Further, it should also be realized that the elements depicted in FIG. 3 are exemplary only; those skilled in the art should well recognize those elements, their configuration, function Lifting devices such as hydraulic cylinders will lift the upper slip assembly in order to position the tubular joint between the power tong and the backup power tong. The power tong will apply torque to a tubular above a joint while the backup tong holds the tubular against rotation below the joint. As is well known in the art, alternative gripping and releasing of the slip assemblies in conjunction with raising and lowering of the upper slip assembly allows successive joint sections to be positioned between the power tong and backup tongs. In this manner, successive sections of tubulars in the string may be made-up or broken out.
[0082] Prior art snubbing units generally require the use of power tongs to rotate the pipe because prior art slip assemblies are intended to only resist the weight of the tubular string and such slip assemblies cannot effectively apply torque (or resist torque applied) to a tubular member. However, in the snubbing unit illustrated in FIG. 2 , first slip assembly 44 may be the slip assembly 24 described in detail in U.S. Pat. No. 6,640,939, which is incorporated herein by reference. Further, first slip assembly 44 is fixed to rotary table 42 such that torque may be applied to slip assembly 44 . The slip assemblies 24 are well adapted to applying torque (or resisting torque applied) to the tubular being gripped. Thus, when slip assembly 44 grips tubular 68 as discussed in U. S. Pat. No. 6,640,939, slip assembly 44 may apply torque to the tubular 68 in the same manner as done by power tongs in some prior art snubbing units.
[0083] Certain embodiments of snubbing unit 2 may include a backup tong 72 positioned on snubbing unit 2 and may be connected underneath lifting assembly 38 . In FIG. 2 , brackets 74 will be fixed to lifting assembly 38 and backup tong 72 , when present, is slid between brackets 74 . In this manner, backup tong 72 will be removably positioned on snubbing apparatus 2 . Backup tong 72 may be any conventional backup tong such as that disclosed in U.S. Pat. No. 4,649,777 to Buck which is incorporated herein by reference. Backup tong 72 will hold lower tubular 68 against rotation while first slip assembly 44 applies torque to upper tubular 68 . In this embodiment of snubbing unit 2 , slip assembly 66 may be any conventional slip assembly.
[0084] Other variations are possible and are considered within the invention. For example, a snubbing unit may not include backup tongs; however, the second slip assembly and use; likewise, the configuration depicted in FIG. 3 has been successfully employed in practice of the present invention.
[0085] Referring now to FIG. 4 , there is a graph showing further details about drilling pressure. In the FIG. 4 graph, the x axis designates pressure whereas the y axis designates well depth. “Pressure” and “depth” are used as labels in FIG. 4 . Marked on the graph are three lines, each denoting that pressure increases as depth decreases. One of those three lines (marked with dashes) denotes fracture pressure 92 . The area marked 94 then, denotes breaking pressure of a formation. A second line in the FIG. 4 graph marked with alternating dots and dashes) denotes pore pressure 96 . The area marked 98 then, denotes an area in which underbalanced drilling (UBD) will not produce anything out of the well. The goal then, is to “manage” well pressure in drilling so that the well pressure (indicated by the solid line in FIG. 4 ) 100 , stays between the pore pressure 96 and the fracture pressure 92 .
[0086] Referring now to FIG. 5 , there is illustrated a processing system that has been successfully employed in an embodiment of the present invention. In FIG. 5 , various elements are depicted that comprise a drilling apparatus (that is, elements 2 and 16 in FIG. 1 ). On line 102 the aforementioned components hopefully produce a hydrocarbon gas and fluid mixture. At the gas buster 104 the gas is extracted. Line 106 , then, transmits liquids and solids only. In frac tanks 108 any dirt is extracted from the liquid, leaving only usable oil. The elements depicted in FIG. 5 are exemplary only. Having a processing system is important but not necessary to practice drilling open hole using snubbing unit. Likewise, it is important but not necessary to practice drilling open hole using a snubbing unit to be able to separate gas and oil and to render any separated oil usable (e.g., by removing dirt from the oil). In a particularly useful processing system, gas, oil and water may be separated, and fluid may be reinjected downhole. Various details of the processing system are not important to practice embodiments of the present invention.
[0087] The apparatus of the invention may connect in any number of ways to their equipment counterparts. Each end of apparatus of the invention may be adapted to be attached in a tubular string. This can be through threaded connections, friction fits, expandable sealing means, and the like, all in a manner well known in the oil tool arts. Although the term tubular string is used, this can include jointed or coiled tubing, casing or any other equivalent structure. The materials used can be suitable for use with fluids typically used in the art.
[0088] Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, no clauses are intended to be in the means-plus-function format allowed by 35 U.S.C. § 112, paragraph 6 unless “means for” is explicitly recited together with an associated function. “Means for” clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. | Methods of drilling open hole and apparatus for achieving same are described. One apparatus comprises a pressure control component strategically positionable in or above a wellbore to isolate downhole pressure while drilling open hole, the pressure control component comprising a rotational drive member effective to rotate a tubular member while drilling open hole. This abstract allows a searcher or other reader to quickly ascertain the subject matter of the disclosure. It will not be used to interpret or limit the scope or meaning of the claims. | 4 |
This invention relates to hypodermic syringe needle destroying devices and methods and more particularly to those utilizing electrical resistance heating at the point of use to incinerate and sterilize used needle parts prior to disposal through conventional waste channels.
BACKGROUND OF THE INVENTION AND PRIOR ART
One-time use of hollow hypodermic syringe needles has become the norm in most health facilities because they cannot be reliably sterilized for reuse. The safe disposal of used needles has however, created a problem of its own; the cost to society is enormous and the end results have been less than satisfactory. Bulk incineration of accumulated syringes and needles at the point of use is an obvious but impractical solution because it cannot be accomplished easily, effectively or even safely. And once started toward the dubious but expensive channels of hazardous waste disposal prior to incineration or burial at a central facility the destiny of the syringes with their needles intact or of the needle assemblies per se seems to be all but uncontrollable.
Mechanical shearing devices have long been used at the point of use to sever used needles from their supports. While shearing goes far to prevent reuse of the needle particularly if it is sheared in sections, it is far from a sanitary solution. The severed parts remain sharp as well as contaminated and the shearing operation itself is believed to spread vaporized contamination as part of the shearing impact.
It has been known from the beginning of the electrical age that metallic electrical conductors having a low ratio of volume to surface area, of which a hollow needle is a classic example, will be incinerated when large electric currents are passed through them. A typical modern day device of this type is shown in U.S. Pat. No. 4,628,169 in which portions of the hypodermic needle are successively heated in relatively short sections from the tip inward to achieve incineration temperatures between fixed, spaced apart electrodes while the needle is still attached to the syringe body. No known prior art, point-of-use devices of this type, however, eliminate sharp needle stubs close to the syringe body and none is able to generate heat for a sufficient time to sterilize needle parts much beyond the points of electrode contact. Predetermined or optimized spacing of the fixed electrodes is not a solution to the problem because widely spaced electrodes, in which the spacing approximates the length of the exposed shaft of the needle, leave relatively long sharp stubs of needles attached to the syringe body, for reasons explained below. In addition, the time interval during which current can flow is minimal, with the circuit often being burned open before there is time for heat to be conducted to sections inward of the electrode coupling points to the needle shaft. Close electrode spacing, on the other hand, also restricts the time for the heat to flow along the needle to parts outside of the electrodes, such as those within the syringe body and, in addition, subjects the electrodes to becoming permanently short circuited by fused needle parts to shut down the entire process. And the most minimal practical electrode spacing nevertheless leaves a critical sharp needle stub requiring careful handling to overcome the latent contamination risks.
SUMMARY OF THE INVENTION
The present invention overcomes the several disadvantages found in the prior art designs by providing electrical resistance, point-of-use needle incinerators having unique electrode configurations and associated parts which accommodate a wide range of needle lengths, provide time constants for complete sterilization, positively preclude exposed needle stubs, and which in a variety of species can disinfect needle parts in shielded or recessed portions of disposable or single use syringe bodies.
In a broader concept of the invention two electrodes are provided which are convergent, either geometrically or by virtue of their ability to be relatively moved during the incinerating process from maximum spacing to minimum while the needle remains in its syringe mounting so that the syringe body with its needle can be moved as one as the electrodes converge to destroy successively all parts of the needle shaft and in the process afford time for the generation and conduction of heat back into the syringe body by maintaining electrical contact at the base of needle during the entire cycle. In an embodiment particularly useful with dental syringes in which the needle hub where gripped by the syringe body is metallic and in which the needle is double ended, one electrode comprises an elongated track which is continuously engaged in sliding contact with the hub to conduct electricity into the needle at the point of entry into the syringe body over the full incinerating cycle during which the electrical circuit can open and close randomly as parts of the needle shaft burn away. The other electrode comprises a conducting ramp convergent toward the first electrode track so that the needle is first heated over its entire length and as the syringe is moved laterally to continuously close the circuit burned open by the ongoing incinerating process, all portions are destroyed back to a point adjacent the hub and sterilized even further. An abutment is provided, which if desired can be part of the second electrode itself, over which the incandescent and momentarily softened stub end of the needle is drawn to detach it from the hub. The needle residue is collected in a disposable container below, such residue, however, being sterile and therefore non-hazardous. In embodiments of the invention adapted for use with syringes in which there is no metallic hub carrying the needle, which is typical of those used in the medical profession, the needle stub can be rendered harmless by bending it in its heated malleable condition at the instant it is released from the electrode coupling to fold it back into the then softened thermo-plastic tip of the syringe body. For situations in which a second needle tip is disposed within the syringe body such as double ended needles frequently used in the dental profession, the convergent electrodes can take the form of a pair of relatively movable electrodes preferably spring loaded and having a geometry enabling them to enter confined areas. The normal preactivation positioning of the electrodes should be such in accordance with the invention that they are spaced apart by the maximum needle length intended to be incinerated. As in the case of the fixed, convergent electrode embodiments, the electrodes converge under movement of the syringe to successively destroy the needle from its tip inwardly toward the hub to reestablish the circuit as it is randomly burned open.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view in perspective of a needle destroying apparatus showing the basic housing part and removed therefrom a disposable and sealable container for sterilized nonhazardous needle ashes and bits, above which is shown a permanent, final cover portion;
FIG. 2 is a view in vertical section taken on the line 2--2 of FIG. 1 looking in the direction of the arrows and showing the disposable container open and in place within the housing;
FIG. 3 is a view in vertical section corresponding to the right hand portion of FIG. 2 and as viewed along the line 3--3 of FIG. 5 and showing in progressive steps the position of a hypodermic syringe body and needle in the process of destruction and sterilization;
FIG. 4 is a view in transverse section taken on the line 4--4 of FIG. 3 looking in the direction of the arrows;
FIG. 5 is a top view of the apparatus shown in FIGS. 1 and 2;
FIG. 5a is a fragmentary view showing the upper electrode removed from the apparatus and in its closed position prior to receiving the needle;
FIG. 6 is a view corresponding to FIG. 5 and as viewed along the line 6--6 of FIG. 7 showing another embodiment of the invention;
FIG. 7 is a top view of the apparatus of FIG. 6;
FIG. 8 is a top view with the cover removed of another embodiment of the invention;
FIGS. 8A, 8B and 8C are views in vertical section taken along the line 8--8 of FIG. 8 showing needle destruction in successive stages of operation; and
FIG. 9 is a view in vertical section of another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-5 an embodiment of the invention is disclosed which is particularly adapted for destroying and sterilizing parts of a used hypodermic syringe S having a hollow needle N attached to a syringe body B (which can be of the autoclavable reusable type or, as is becoming more common, is discarded after a single use). The illustrated syringe needle is a type used in the dental profession; it is double-ended and carried between its ends N-1 and N-2 by a metal hub H gripped by the forward end of the syringe body either in a detachable coupling as when the syringe body is sterilizable for reuse, or permanently molded into an expendable syringe body to be discarded as a unit after one use.
The needle destroying and sterilizing apparatus includes a housing 20 adapted to be self-powered or connected to conventional electrical service mains (not shown) and preferably positioned near the point of use of the syringe by the professional operator. The housing 20 is formed with a deep slot 21 bounded by depending side walls 21a and 21b. The surface of the housing is formed with a slide track 22 defined by lateral guide ribs 22a and 22b to receive the forward end of the syringe body or barrel B and to position the needle N correctly within the housing for carrying out the incinerating process. The housing can include a viewing window with appropriate light filtration to allow monitoring of the incinerating process or alternatively the entire housing can be formed of a semi-transparent material such as smoked plastic.
The housing 20 contains a high current, low voltage power source 23 which can take the form of a rechargeable battery capable of delivering approximately 3 to 6 volts (across the load when the impedance is relatively high) served by a low voltage DC battery charging source through a power cord 24. If desired the power source in the incinerating unit can include its own battery charging circuitry, in which case it can be powered through the cord 24 directly from the AC mains. Alternatively the power source can be a step-down transformer, the primary winding of which is connected to the AC mains by the power cord 24. The DC source or the transformer secondary winding, the latter preferably developing an AC output not greater than 12 volts, is connected across the two electrodes of an electrode array (described below in several embodiments) through a fuse 25 which is preferably a bimetallic, automatic reset fuse via upper and lower contacts 25a and 25b disposed in the housing 20. Currents ranging from 9 to 25 amperes are adequate in most cases to incinerate hollow hypodermic needles of conventional size ranging in size from 18 to 30 gage. The electrode array which engages the needle shafts can be designed for periodic replacement and thus can be incorporated in a disposable box 27 which slides like a drawer in and out of the housing 20. It will be understood, however, one or both of the electrodes can be made a permanent part of the housing 20 or they can be removed from the used box and mounted in a replacement box. When the expendable box 27 is ultimately removed from the housing for disposal with its spent electrodes and a volume of incinerated, sterile needle ash and discrete bits, it can be sealed in accordance with the invention by the cover 31 taken from its duplicate replacement box by reversing the cover lengthwise to bring its interior locking cleats 31a into register with locking cleats 27a on the outside of the box 27. The expendable box 27 is then able to be thrown into conventional channels of waste disposal, free of hazardous contamination.
With the incinerating box in place in the housing and locked in position by a latch 29, with its top removed, the electrode array is centered under the slot 21 and upper and lower electrode contacts 30a and 30b are in engagement with the contacts 26a and 26b, respectively, to energize the electrodes. An on-off switch and pilot light are not illustrated in the drawing but can be provided, if needed.
The disposable incinerating box 27 in the illustrated embodiment incorporates the electrode array as renewable elements subject to wear and designed to be discarded after use for, say, one thousand incinerations. The upper electrode 32 forms a track adapted to engage the metallic hub H of the syringe and to conduct electricity to the needle at points closely adjacent the inner end of the needle where it enters the syringe body. The upper electrode as best seen in FIG. 5A can take the form of a number 10 springy wire of electrically conducting material such as copper or aluminum having two elongated parallel arms 33a and 33b normally spring biased together by the action of the circular head 34 which defines an enlarged opening to receive needle N at the entry point at the left hand end of the track as viewed in FIG. 2. The conducting arms 33a and 33b rest in groves 35 and 36 formed in the upper surface of the incinerating box, with the free ends of the arms being splayed outward to center the paired arms directly above the narrow elongated grove 37 in the upper surface of the box. The upper electrode 32 is secured in place by means of a mounting screw 38 which clamps a narrow extension loop 39 to the box body and also secures contact spring 30a which engages the transformer contact 26a.
The electrode array is completed by complementary second electrode 40 which is a metallic conducting plate electrically coupled by the contact 30b to the lower contact 26b. The lower electrode 40 is supported in upwardly convergent relationship with the upper electrode 32. The upper end 41 of the electrode 40 defines a wiping barrier with its uppermost sharp corner which is spaced from the upper electrode 32 by a distance corresponding to the amount by which the hub A extends downward through the upper electrode arms 33a and 33b when the head of the syringe body B is in sliding engagement with the track 22 as best seen in FIGS. 3 and 4. If desired the barrier section 41 can be made more pronounced by forming it at a steeper angle as illustrated by the barrier 41' of FIGS. 6 and 7.
The spacing between the electrodes at the left hand end of the incineration chamber exceeds the length of the longest needle to be accommodated by the unit. As best seen in FIG. 3, with the end of the syringe body B seated on the slide track 22, the needle hub H, when the syringe is moved from the enlarged electrode opening 38, will be engaged laterally by the spring loaded electrode arms 33a and 33b which will be forced apart in their support grooves 35 and 36. When the depending end of the needle N reaches the upwardly convergent electrode 40 current will flow through the needle body from hub to tip, quickly achieving incandescence. The needle will typically burn through at a point between its ends where the cooling effect of the electrodes is least felt, with maximum cooling typically occurring near the hub end due to the relatively large metal masses of the twin electrode arms. The ability of the heated needle to bend will increase the time before the break, if any, occurs to open the circuit, after which further sliding movement of the syringe will quickly reestablish the circuit to resume the heating cycle. By the time the needle reaches the barrier 41 the upper or hub end of the needle will have been heated and reheated over a relatively long time cycle of say 2 to 3 seconds causing heat to be conducted upward into the syringe body to convey sterilizing temperatures into the syringe body beyond the electrode coupling point. Any liquids within the needle will be heated to sterilizing temperatures and driven in a superheated state upward into the syringe barrel.
When the remaining needle stub, heated to incandescence and therefore malleable, engages the barrier 41 it will be detached from the hub H by the wiping action of the hub over the lip of the barrier and will establish a fleeting direct electrical coupling between the hub H and the electrode, generating additional heat. If necessary the hub can be wiped back and forth over the barrier 41 to detach the stub. The physical wiping action will also serve to clear the barrier area of residue. After passing the barrier 41 the syringe body, free of its sharp stub is lifted from the unit. If the syringe is capable of being reused the hub H and internal needle part N-2 can be detached therefrom and further incinerated by the species of the invention described below having reference to FIGS. 8, 8A, B, and C.
Referring to FIGS. 6 and 7 there is illustrated a point-of-use needle incinerating device which is specifically designed to accommodate a type of hypodermic syringe S' widely used in the medical profession in which the hollow needle N' is carried by hub H' formed of plastic and supported by the syringe body B, all of which are intended to be destroyed after a single use. The needle N' is in most cases single ended and is molded directly into the plastic hub H' (without an interposed metallic hub part such as the hub H in FIGS. 1-5A).
The housing and basic electrode parts are substantially identical to those described above having references to FIGS. 1-5A and are identified by like reference numerals with the upper electrode 32 having elongated arms 33a and 33b adapted to be spread apart against the inherent spring action of the head 34 by the thickness of the shaft of the needle N' (as opposed to the greater thickness of the metallic hub H in FIGS. 1-5A). The lower electrode 40 is convergent upwardly toward the upper electrode 32 and can terminate in barrier 41 which is spaced from the upper electrode by a distance which precludes unintended permanent short circuiting by bits of the burned needle becoming fused therebetween. The spacing also defines the length of the needle stub.
Immediately beyond the electrically conducting barrier 41 in the direction of travel of the syringe the housing is formed with an upwardly inclined barrier 42 to a peak 43 followed by a deforming trough 44 of approximately the same width and contour as the lower end of the syringe hub H'.
In operation the Syringe S' is inserted at the left hand end of the track with the needle N' pointing down, until the lower shoulder of the syringe body B' engages the slide track 22. The syringe is then slid to the right as viewed in FIG. 6 until the tip of the needle engages the lower electrode 40 and the shaft of the needle is engaged by the electrode arms 33a and 33b close to the lower end of the hub H'. The electrical circuit is thus completed to heat the entire needle shaft to incandescence and destruction. Thus heated it first bends to enlarge its contact area with the lower electrode and in some cases breaks off as a fully sterilized but deformed section. Meantime the syringe is moving in its track to maintain continuous heating of the needle from the hub downward by electrical resistance heating and from the hub upward into the body of the syringe by conduction. In the process any contained liquids will become vaporized and sterilized. The process continues over a finite time interval of 2 to 3 seconds until all portions of the needle shaft below the level of the top of the electrode barrier 41 are destroyed. A heated shaft stub having a length corresponding to the spacing between the electrode 32 and the top of the barrier 41 remains and is on the order of 2 mm. Immediately, the red hot stub engages the inclined barrier 42 and begins a bending-over process which reaches 90 degrees as the stub passes over the peak section 43, after which it drops into the contoured trough 44 which peens it over. Under the impact with the base of the trough it is pressed into the now softened thermoplastic hub H' to render it harmless as well as sterile. The syringe body which remains can be disposed of by conventional waste disposal means without requiring the use of either hazardous or sharp protection containers. Needle residue, sterile and harmless, is collected in the disposable box 27 which in time due to filling as well as wear of the electrodes will be sealed by a cover 31 as described above and discarded.
If desired the deforming process for the needle stub can take the form of a shearing device or cut off wheel positioned to act on the stub in its heated condition at the instant it leaves the electrodes.
Referring to FIGS. 8, 8A, B and C there is illustrated another embodiment of the invention which is adapted to dispose of a double ended hypodermic needle assembly S-2 including an external sharpened portion N-1 (shown in phantom lines and having previously burned away) and an internal sharpened portion N-2 carried by the central metallic hub H-2 attached to the plastic carrier body B-2. The needle incinerator includes base 47 supporting a disposable outer container 48 having a detachable cover portion 49 within which the permanent electrode array 50 is removably mounted. The electrode array 50 includes a three legged base portion 51 having a pedestal 52 extending upwardly therefrom formed of electrically insulating material and carrying at its upper end cup shaped first electrode 53 connected to one terminal 54a (shown schematically) of a low voltage source (not shown) in the base 47.
The second electrode assembly 55 is adapted to be convergent toward the first electrode 53 by virtue of its ability to be moved axially downward on the pedestal 52 against a compression spring 56 connected at its lower end to a second terminal 54b (also shown schematically) of the low voltage power source. The second electrode assembly 55 comprises a metal cage having four lateral arms 55a, b, c and d attached at their lower ends to a collar 57 surrounding the pedestal 52 and attached to the upper end of the compression spring 56. The cage arms carry an electrode disc 58 having a central contoured electrode ring 59 adapted to be engaged by the metal hub H-2 of the needle assembly. A conical plastic shield 60 and a cylindrical skirt 60' carried by the arms 55a, b, c and d shields the interior of the container 48 at the radial space between the inner wall 49a of the cover 49 and the electrode arms 58.
With the needle carrier body B-2 fitted over the upper cage arms and the electrode disc 58 with the needle N-2 entering the ring 59 it will come to rest with the pointed end of the needle pointed toward the inner electrode 53 and the metallic hub H-2 resting on the upper electrode 59 to establish electrical contact therewith. The carrier body B-2 is then pushed downwardly causing the inner tip of the needle N-2 to engage the inner electrode 53 to establish a flow of current through the needle portion N-2 which will incinerate the needle in the manner described above as the electrodes converge. Suitable stops are provided so that the electrodes 53 and 59 remain out of contact at the extreme end of the incinerating motion as shown in FIG. 8C. The remaining carrier body B-2 can then be removed and discarded. It will be understood that the exposed needle portion N-1 has been previously incinerated by following the same procedure with the needle carrier body reversed. Any needle stubs remaining at the end of the incinerating process can be sheared off by moving the carrier laterally causing the ring electrode 59 to function as a barrier similar to the action of the barriers 41 and 41' described above to shear off the red hot stub. Also, it will be seen that the relatively movable electrodes 53 and 59 in action are convergent and duplicate the functions of the fixed convergent electrodes 31 and 40 of the species of the invention described above having references to FIGS. 1-5A and FIGS. 6 and 7. In all cases the needle is heated throughout the entire cycle from the hub outward to the needle tip allowing time for heat to be conducted to interior parts not spanned by the electrodes and assuring complete heating of all needle shaft parts. Also, the embodiment of the invention shown in FIGS. 8 and 8A, B and C can be used to incinerate the medical needle designs of the type shown in FIGS. 6 and 7.
When the needle parts are incinerated, the ash and pieces of sterilized needle shaft will drop through the cage arms supporting the upper electrode into the cavity within the container 48 surrounding the pedestal 52 and spring 56. After a plurality of incinerations the container 48 can be replaced with a fresh container, capped and discarded after removing the electrode array 50, which is adapted to be installed in the replacement container. Separable electrical contacts (not shown) can be provided for this purpose. Alternatively, the container 48 can be emptied into a non-hazardous waste disposal container and reassembled with the electrode array.
It will be understood that the apparatus of FIGS. 8A-C can be reversed in its mechanical action so that the lower electrode 53 is moved upward toward the upper electrode 59 either by lever action or cocked spring action completed, if desired, by speed control means to establish a relatively slow rate of travel. In such arrangement the syringe body is simply manually held or clamped at the lid with the upper electrode 59 in engagement with the hub H-2, with the lower electrode 53 being supported by a vertically movable carrier to establish convergent electrodes to destroy the needle shaft from the tip inward. As in all embodiments, electrode contact adjacent the hub is continuous throughout the cycle.
Referring to FIG. 9, there is illustrated another embodiment of the invention which adapted to destroy double-ended needle assemblies S-2 of the type frequently used by the dental profession. A base 61 including a power supply supports a detachable container 62 having a removable cover 63. The cover carries an upper electrode 64 on a support 65 and the container carries the complementary convergent lower electrode 66 on a yielding spring arm 67 connected to an electrical contact 68 (shown schematically) which couples to the power source in the base 61. The upper electrode is energized from an electrical contact 69 through a conductor 70, spring finger contact 71 and conductors 72 and 73. The conductor 72 is bare and seated within a groove 74 in which the spring finger contact 71 rides in sliding contact with the conductor. If desired, the conductor 72 can be covered by an insulator 75 at the upper end of the groove to break the electrical circuit when the cover is lowered to the point of complete needle incineration to open the circuit.
A floating carrier assembly 76 having an inner annulus 77 and an outer annulus 78 joined by radial spokes 79 rides on a light compression spring 80 seated on an abutment 81 and secured against rotation by a vertical rib 82 on the inner wall of the container received in a slot 83 in the outer edge of the annulus 78. The inner annulus 77 is a seat for holding the base B-2 of the needle assembly, which is identical to that described above having reference to FIG. 8A. The body B-2 rests on radially yieldable fingers or alternatively on a yieldable 0-ring 84 and is constrained against rotation by elements 85 which engage the upper side of the body B-2.
Attached to the annulus 78 of the floating carrier 76 is a transparent sleeve 86 forming a finger gripping surface for stabilizing the floating support 76 when the needle assembly S-2 is mounted therein. If desired, an optional upper coil spring 87 can be secured to underside of the cover 63 to rest releasably on the upper edge of the sleeve 86 to apply balancing forces against the lower coil spring when the cover 63 is lowered, as described below. This force balance relieves the needle part N-2 of most of the bearing load necessary to lower the support 76 and the needle assembly carried thereby into rubbing engagement with the lower electrode 66.
Also, by appropriate selection of springs 80 and 87, the system can be tuned so that the upper and lower electrodes both converge toward the upper and lower ends of the hub at the same time, provided however that the upper spring is stronger than the lower. If for example, needle part N-1 is twice as long as N-2, a spring strength ratio of 2 to 1 favoring the upper will bring the two electrodes to the hub H-2 at the same time. Omitting the upper spring will bring the upper electrode to the hub before substantial movement of the needle assembly occurs, thus delaying complete incineration of the lower needle part and removal of its stub, if any by the barrier 66a.
In operation, when the dentist has finished with the hypodermic injection of a patient, with the cover 63 removed the syringe barrel (not shown) with its detachable needle assembly S-2 is placed vertically into the annulus 77 and the syringe barrel unscrewed from the expendable needle assembly. With the syringe barrel removed, the cover 63 is placed on the container and slowly lowered to bring the upper electrode 64 into contact with the upper needle part N-2 and the lower needle part N-1 into contact with the lower electrode 66. The floating support 76 then moves downward as necessary to establish the current flow through the needle through wiping action on the inclined electrode surfaces.
The needle will immediately be heated to incandescence and will sterilize and destroy itself as the cover is slowly lowered to cause the electrodes 64 and 66 to coverage to points of close proximity to the top and bottom of the hub H-2. This point can be signalled by a releasable detent (not shown). Further smart pressure on the cover 63 will drive the body portion B-2 downward through the yieldable means 84 and in the process will force the lower electrode downward on its spring arm 67 until the body falls into the repository below. Any stub remaining from the needle part N-1 will be broken away by the barrier 66a on the edge of the electrode 66. The momentary dead short across the electrodes by the metal hub H-2 can, if necessary, be overcome either by the circuit breaker or by the insulator 75. As the hub H-2 snaps over the barrier lip 66a on the electrode 67 any stub remaining from the needle N-1 will be removed. It will be understood that the lower end of the container 62 (shown foreshortened in the drawing) is subject to many design variations including, if desired, a removable drawer configuration similar to the drawer 27 in FIG. 1.
While the invention has been illustrated as applied to embodiments found in the field of dental hypodermic syringes it will be understood that the principles of the invention can be adapted to other syringe needle structures having exposed or imperfectly concealed needle portions. Also, additional shielding against the escape of sparks from the relatively small openings can be provided by movable iris vanes or by flexible filaments adapted to yield with the movement of the syringes such shields preferably being disposable with the collection boxes for destroyed needle parts. It will also be understood that dampers can be included to control the rate of syringe motion under hand power or mechanical drives can be used to replace the hand driven motion of the syringe bodies to provide for precision timing of the incineration process. Also, while the lower electrode 40 is shown as being upwardly convergent toward the upper electrode 32, the upper electrode can be contacted downwardly and mounted in a sloping wall part of the housing. The invention should not therefore be regarded as limited except as defined in the following claims. | A hypodermic syringe needle destroying apparatus and method using electrical resistance heating between electrodes which are convergent either geometrically or by virtue of relative movement to conduct incinerating currents first throughout the entire length of the contaminated needle and thereafter over progressively shorter lengths until the entire needle is destroyed. Any remaining needle stub can be removed or deformed while in its heated state by impacting it against a deforming barrier. | 0 |
BACKGROUND OF THE INVENTION
The invention relates to improvements in charging valves which pass a controlled predetermined amount of material from a supply to a working machine requiring the amount of material. More particularly, the invention relates to a bucket wheel charging valve having parallel alternately rotatable wheels each with cells or pockets on the periphery thereof.
Passing a valved charge to a work machine such as a comminution machine having a flow through of hot gasses with the materials is accomplished with the use of a bucket wheel or a double oscillating charging valve. Double oscillating valves are very disadvantageous because of the necessity of discontinuous operation, but also because of the necessity of low supply speed as the materials passing through the charging valve require a long release and dropping time. By comparison, bucket wheel charging valves which have heretofore been used make it possible to have a continuous operation, but difficulties are encountered with the adhesion of material onto the walls of the bucket which is particularly true when charging moist materials. Material depositing and adhering to the walls of the charging valves lead to a substantial decrease or to an undesirable alteration of the output quantity passed by the valve. Quantitatively controlled and uniform charging of a work machine with materials, particularly with moist or adherent materials has not been possible with valves heretofore used with the types of aggregates and material referred to.
It is accordingly an object of the present invention to provide an improved bucket wheel charging valve which makes possible the uniform charging of a work machine with materials, and particular moisture adhesive materials.
In accordance with a feature of the invention, the object is attained by providing a bucket wheel where the wheel has arcuate recesses in the periphery having the recesses or cells with their inner walls constructed on the arc of a circle. The bucket wheels are rotated alternately with each alternately driven at a prescribed angle of rotation which is equal to the width of the particular cell or recess of the other wheel. The bucket wheels are also arranged to be spaced from each other so that the outer rim end of the spoke between the recesses passes in close running or cleaning relationship to the wall of the recess of the opposite bucket wheel. The bucket wheel charging valve construction of the present invention includes an outer rim of spokes between each of the pockets so that the rim of the driven wheel slides along the inner wall of the arc shaped recess of the non-driven wheel and with the wheels driven alternately, there is a constant cleaning of each of the bucket walls. The buckets of the bucket wheels are maintained in operation and always kept free from adhering material. The bucket wheels are driven at a predetermined controlled arcuate rotation and at a controlled speed so that constant quantities of material are supplied to the work machine. The bucket wheel charging valve construction of the invention makes possible a constant uniform charging of the treatment or processing machine with materials, and particularly with moisture adhesive materials, and therefore, optimum control of the amount of material passed is attained over a long period of time which is not altered by the build-up of material to foul the valve and change its rate of delivery.
A further feature of the invention is that there is provided a drive for the bucket wheel charging valve including a crank with a connecting rod which connects to lever arms that are connected to a rotary drive on the axis of each of the bucket wheels and the crank drive continues in uniform rotation to drive the bucket wheels alternately in counter-rotation through a specific angle which includes the width of the cell formed on the periphery of the bucket wheel. The crank drive with its connecting rod connected to the lever arms are connected to a one-way rotary drive arranged on the axis of each of the bucket wheels so that they are alternately rotated through a specific angle of rotation.
A further feature of the invention is the provision of a rotary drive for each of the bucket wheels in the form of a free wheeling or a gripping clutch roller drive arrangement or a pawl drive ratchet arrangement.
Other advantages, objects and features, as well as equivalent structures which are intended to be covered herein, will become more apparent with the teaching of the principles of the invention in connection with the disclosure of the preferred embodiments in the specification, claims and drawings, in which:
DRAWINGS
FIG. 1 is a vertical sectional view taken through the housing of a bucket wheel charging valve constructed and operating in accordance with the principles of the present invention:
FIG. 2 is a somewhat schematic view of the exterior of the bucket wheel charging valve illustrating the external crank driving mechanism thereof;
FIG. 3 is a detailed enlarged view, with parts omitted for clarity, of a free wheeling clutch drive for the valve; and
FIG. 4 is an enlarged detailed view of a pawl drive for the valve, illustrating a drive for only one of the wheels.
DESCRIPTION
FIG. 1 illustrates a housing 1 with counter-rotatable bucket wheels 2 and 3 supported on axles 4a and 5 within the housing.
Each of the bucket wheels has a series of cells or recesses or pockets 4 on its outer periphery with the inner walls of the recesses being constructed on the arc of a circle. The arc of the circle is such that the center of the arc is coincident with the shaft of the opposite wheel when the recess is facing said opposite wheel. For example, in FIG. 1, the wall 4b has its center at the axis of the shaft 4a of the opposite wheel. Similarly, the center of the arc of the wall 4c is coincident with the axis of the shaft 5 of the opposite wheel.
The distance or spacing between the shafts 4a and 5 of the bucket wheels 2 and 3 are such that the rim of the driven bucket wheel passes in close running relationship to the inner wall of the recess of the non-driven bucket wheel. Each of the recesses have spokes 6 therebetween with the outer tips 6a of the spoke being the rim of the wheel. Thus, the rim 6a of the spokes 6, shown in FIG. 1, will traverse the dotted line path 6b as the wheel 4 is advanced in the direction shown by the arrowed line 4d. The tip 6c or rim, will traverse the line 6d as the wheel 6 is advanced in the direction of the arrowed line 6e.
The bucket wheels 2 and 3 which are illustrated are each provided with four equally spaced recesses spaced at an angle of 90° with respect to each other. With this spacing, each bucket wheel is alternately advanced 90° when it is driven.
Means are provided for supplying a flow of material to the valve mechanism which will flow from a conduit 7a above the valve, and a plate shaped material distributing device 7 is shown in the center of the spacing above the bucket wheels to aid in the material flowing directly into the recesses.
After the material passes the valve, it flows downwardly in the direction of the arrowed line 7b to a work machine receiving the material.
As illustrated in FIG. 2, the drive mechanism for the bucket valve includes a crank 8 which is driven in rotation by a power means, not shown. Preferably, the crank can be driven at a constant speed rotation, and the mechanism provided will incrementally and alternately advance the bucket wheels. The crank has a connecting rod 9 which is connected to simultaneously pivot lever arms 10 and 13. An actuator rod or link 12 interconnects the free ends of each of the lever arms 10 and 13 so that they will simultaneously be driven in pivotal motion. The lower end of the lever arms 10 and 13 are connected to the bucket wheels through one-way free wheeling clutches as will be described in connection with FIG. 3 or in an alternate arrangement, in connection with FIG. 4.
The rotary drives are shown generally at 11 and 14 in FIGS. 2 and 3, and include an annular ring or raceway 15 or 16. The drive shafts 4a and 5 have hubs at their ends within the rings 15 and 16. Driving rollers 17 and 18 are positioned between the hubs and the inner surface of the rings. The hubs 29 and 30 have recesses around their periphery containing the rollers 17 and 18 respectively, and the recesses are so constructed so that when the drive mechanism moves to the left in FIG. 3, the shaft 4a will be driven forwardly, but the shaft 5 will remain stationary. When the drive mechanism moves to the right in FIG. 3, the shaft 5 will be driven forwardly while the shaft 4a will remain stationary.
These recesses are arranged so that the hub 29 has a portion 17a sloping toward the inner surface of the ring 15 so that the roller will drive the hub when the ring 15 moves in a counter-clockwise direction, but the roller will move back against a shoulder 17b when the ring 5 moves in a clockwise direction. Similarly, the hub 30 has a sloping portion 18a leading toward the inner surface of the ring 16 so that the hub 30 will be driven when the ring 16 moves in a clockwise direction, but the roller 18 will move back against a shoulder 18b so that the hub 30 is not driven when the ring 16 moves in a counter-clockwise direction.
With reference to the arrowed lines, when the crank arm 9 moves in the direction of the solid arrowed line 19, the link 12 moves in the direction of the solid arrowed line 19a, and each of the arms 10 and 13 will swing to the left. The ring 15 will move in the direction of the solid line arrow 20, and the shaft 4a will be driven in rotation in the direction of the arrowed line 34. Simultaneously, the ring 16 will move in the direction of the broken arrowed line 21, and the ring 16 will turn freely on the hub so that the shaft 5 will not be driven. When the crank 9 moves in the opposite direction, as indicated by the broken arrowed line 33, and the link 12 moves in the direction of the broken arrowed line 32, the crank arm 13 moves in the direction of the solid arrowed line 22 driving the ring 16 and driving the shaft 5 in the direction of the arrowed line 35. The ring 11 will move in the direction of the broken arrowed line 31, and the shaft 4a will not be driven. Thus, with the back and forward movement of the crank arm 9, the shafts and their supported bucket wheels alternately rotate toward each other in the direction of the arrowed lines 4d and 6e of FIG. 1.
The size of the crank 8 is chosen relative to the length of the lever arms 10 and 13 so that they will swing through an arc of 90° with each rotation of the crank. When bucket wheels are used with recesses that are spaced apart more or less than 90°, corresponding change in the size of the crank arm 8 and lever arms 10 and 13 are chosen. A variable speed control may be provided for the crank arm 8 as indicated at 36 so that the quantity of material passed will be a function of the speed of operation of the crank 8 as determined by the control 36.
FIG. 4 illustrates an alternate type of drive with a ring 26 operated by a lever arm 26a driven by a crank mechanism similar to that shown in FIG. 3. A hub 23 is connected to the shaft of the bucket wheel and is provided with pockets 24 on its outer periphery with pawls 27 therein. The pawls are arranged so that as the ring 26 is driven in the direction of the solid arrowed line 37, the pawls will effect a driving engagement between the ring 26 and the hub 23 to drive the bucket wheel. When the ring 26 moves to the right, in the direction of the broken arrowed line 28, the pawls 27 will release so that the hub 23 is not driven. The hub is shown driven to the left in the direction of the arrowed line 25 so that as illustrated, the mechanism will be connected to the shaft 4a for the right bucket wheel. A corresponding pawl or ratchet drive, such as shown in FIG. 4, will be provided for the shaft 5 of the left bucket wheel.
Instead of bucket wheels with four buckets as shown in the drawing of FIG. 1, bucket wheels may be installed which have three, six or other numbers of buckets. Each recess, of course, will be constructed with its wall in the shape of the arc of a circle so that the tooth of the other bucket will sweep the arc and perform an automatic cleaning operation as it discharges the recess. When wheels are employed with numbers of recesses other than those illustrated in the drawing, the crank and rotary drive are adjusted so that the wheels in each case are rotated at an angle equal to the spacing between buckets. The recesses are uniformly spaced on the wheel with the spokes uniformly spaced between the recesses. With X equalling the number of recesses employed, the arc of rotation of each wheel for each advance is X/360 degrees. Thus, with a wheel having three buckets, each wheel must be rotated for each time it is drived through an angle of 120°. Similarly, a wheel with six buckets is advanced 60° with each forward rotational drive. Other drive mechanisms may be employed such as employing crank guide drives or oscillating hydraulic cylinders.
In operation, as shown in FIG. 1, material drops downwardly through the conduit 7a onto the bucket wheels, and the bucket wheel 4 is rotated to the left in the direction of the arrowed line 4d through 90° so that the rim or end 6a of the tooth sweeps the pocket 4b and drops the contents of the pocket downwardly in the direction of the arrow 7b. The other bucket wheel 6 is then driven to the right in the direction of the arrowed line 6e so that its tooth end 6c sweeps the pocket 4c (of course, since the wheel 4a is advanced, the pocket 4e will be in position to be swept by the tooth 6c). The contents of the pocket 4e then drops downwardly, and the pocket is simultaneously cleaned.
The inner arcuate walls 1a and 1b of the housing are arranged so that the ends of the teeth will be in close running relation thereto to form a gas-tight closure, and the pockets of material themselves will form a closure between the two bucket valves. The charging will remain uniform and as a direct function of the speed of operation. Also, it will be seen that the bucket wheels may be readily changed with more or less pockets, and the size of the pocket correspondingly changed as may be dictated by the necessities in physical properties of different materials.
The bucket valve remains constantly cleaned throughout continued operation insuring accuracy and reliability and eliminating the need for cleaning and servicing. | A bucket wheel charging valve having an outer enclosing housing with first and second counter-rotatable wheels on parallel axes therein with each wheel having cells along the periphery with the cell walls swung on an axis coincident with the opposite wheel and the tip end of the spokes between the cells sweeping the cells of the opposite wheel as each wheel is incrementally advanced while the other cell is stationary. | 1 |
CROSS REFERENCES TO RELATED APPLICATIONS
This application is a continuation of international patent application WO 2006/105932 A1 (PCT/EP2006/003054), filed on Apr. 4, 2006, designating the U.S., which international patent application has been published in English language and claims priority from German patent application DE 10 2005 015 522, filed on Apr. 4, 2005. The entire contents of these priority applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to an intracorporeal probe, for example preferably for examining hollow organs or natural or artificially created body cavities in the human or animal body, the probe being designed in the form of a capsule that can be introduced into the body without external connecting elements, comprising a housing and an image pickup unit inside the housing that is designed for optically recording, for example imaging, a region (termed pickup region below) outside the probe.
An intracorporeal probe of the aforesaid type is known in general, for example from DE 101 46 197. EP-A-0 667 115 also discloses an intracorporeal probe that is designed in the form of a capsule that can be swallowed by the patient to be examined in order to be able to examine the gastrointestinal tract visually. The optical signals received from the probe are transmitted telemetrically via a transmitter present in the capsule to extracorporeal space and visualized there. This known autonomous video probe certainly enables visual inspection of the gastrointestinal tract, and permits the images to be transmitted to the outside telemetrically, but undertaking a diagnosis with the aid of the transmitted images is exceptionally difficult. The reason for this resides in the fact that, although the position of the probe inside the patient can be determined in the meantime relatively well, the regions picked up by the image sensor installed in the probe are of a rather random nature. It is not possible for specific regions inside the gastrointestinal tract to be specifically picked up. The image information obtained by the probe is consequently more of a random product and cannot be determined by the examining doctor.
Against this background, the invention is therefore based on the object of developing the intracorporeal probe mentioned at the beginning so as to enable a controlled, flexible and targeted visualization.
SUMMARY OF THE INVENTION
According to the invention, this object is achieved with regard to the intracorporeal probe mentioned at the beginning by virtue of the fact that the image pickup unit is held in a fashion capable of moving inside the housing in order to be able to vary the pickup region by means of such a movement.
That is to say, in other words, the alignment of the image pickup unit can be varied such that the straight ahead front view of previous probe solutions can be varied via an appropriate movement of the image pickup unit to provide a side view as well, without there being variation in the position of the probe itself. Overall, it is thereby possible for the field of view of the image pickup unit to be greatly enlarged by varying its position inside the probe.
The examining doctor obtains much more image information with the aid of the inventive probe while the probe is passing through the gastrointestinal tract.
In a preferred refinement, the image pickup unit has an image sensor and a pickup optics. The image pickup unit preferably has at least one illumination element for illuminating the pickup region.
The aforementioned measures have the advantage that a very compact image pickup unit is provided that owing to its movable mounting inside the housing of the probe moves the image sensor and pickup optics together. It is thereby possible to achieve a simpler control for the execution of a movement, since only one component need be moved.
The fact that the image pickup unit also has an illumination element, which means at the same time that the illumination element cooperates in the movement of the image sensor and the pickup optics, enables optimum illumination of the corresponding pickup region. The illumination element always illuminates the selected pickup region without requiring a dedicated control.
In a further preferred refinement, the housing is of elongated shape, and the image pickup unit is held in a fashion capable of swiveling about an axis that runs perpendicular to the longitudinal axis of the probe. It is preferred to provide a first motor that is coupled to the image pickup unit in order to move the latter. The motor is preferably a wobble motor, in particular a Q-PEM motor.
The aforesaid measures have proved to be particularly advantageous in practice. In particular, a very large pickup region is permitted by the ability of the image pickup unit to swivel about an axis that runs perpendicular to the longitudinal axis of the probe. The pickup region itself, that is to say the position of the image pickup unit, can be set via the first motor, preferably via control signals output by the examining doctor. Of course, it is also conceivable to control the motor in accordance with a permanently prescribed program without external influence.
The use of a wobble motor has proved to be advantageous as regards the aspects of energy and accuracy in particular. A wobble motor requires little energy and can be moved in very precise small incremental steps.
In a further preferred refinement, a coupling element is provided between the motor and image pickup unit and is designed to convert a rotary movement of the motor into a transverse movement. The coupling element is preferably fitted on the image pickup unit in a fashion remote from the swiveling axis, and the coupling element preferably comprises a flexible shaft.
These measures permit a very efficient swiveling of the image pickup unit about the axis perpendicular to the longitudinal axis. The flexible shaft in this case undertakes the swiveling of the image pickup unit when the motor rotates.
It goes without saying that the previously described approach to a solution for swiveling the image pickup unit about the transverse axis (with reference to the longitudinal axis of the probe) is a purely exemplary one. The person skilled in the art will recognize that other possibilities exist for appropriately coupling the image pickup unit to a motor in order to achieve a swiveling movement about the transverse axis. Thus, for example, the coupling of a motor to the image pickup unit could be performed via the transverse axis, that is to say the transverse axis or a corresponding transversely running shaft transmits the rotary movement of the motor to the image pickup unit.
In a further preferred embodiment, the image pickup unit is held in a fashion capable of rotating about the longitudinal axis of the probe.
This measure has the advantage that the pickup region can be greatly enlarged once more. By swiveling the image pickup unit about the transverse axis, and by rotation about the longitudinal axis it is possible to bring the image pickup unit into many more positions such that the pickup region can pick up at least a hemispherical region around the probe.
A second motor is preferably provided in order to rotate the image pickup unit about the probe longitudinal axis. With particular preference, the image pickup unit and the first motor are interconnected with the aid of the coupling element in order to be able to rotate jointly about the probe longitudinal axis.
In a further embodiment, a mounting frame that carries the image pickup unit and the first motor is provided in the housing, and is preferably coupled to the second motor for rotation about the probe longitudinal axis.
This is a conceivable solution for holding the image pickup unit and the two motors inside the probe. However, it will be clear to the person skilled in the art that there are further possible ways of holding the image pickup unit, the first motor and the second motor appropriately in the housing of the probe so as to ensure fluidity of swiveling about the transverse axis, and of rotating about the longitudinal axis.
In a further preferred embodiment, the image sensor is a CMOS image sensor, for example an HDRC (high dynamic range camera) type CMOS image sensor, preferably with a resolution of 768×496 pixels. The CMOS image sensor is preferably operated at an imaging rate of at least two, in particular ten, more preferably at least twenty images per second.
The aforesaid image sensor has proved in practice to be particularly advantageous, particularly with regard to its resolution and its photosensitivity. Such a type HDRC CMOS image sensor is described, for example, in German patent DE 42 09 536.
In a further preferred refinement, the probe has a transmitting unit for transmitting the acquired images from intracorporeal space to extracorporeal space, an energy receiving and supply unit that preferably receives energy inductively from extracorporeal space and supplies units inside the probe with energy, and a locating unit for locating the intracorporeal position of the probe from the extracorporeal.
The energy receiving and supply unit can be used to transfer into the probe energy from extracorporeal space that then serves to supply the respective elements, in particular the image pickup unit and the motors. The locating unit can be used for accurate determination of the position of the probe inside the gastrointestinal tract of the patient, the alignment or position of the longitudinal axis of the probe relating to this purpose, as well. These data enable the examining doctor on the one hand to be able to classify and evaluate the received images more effectively and, on the other hand, to have the motors controlled in a targeted fashion and thus to vary the pickup region.
It is thereby possible to pick up specific pickup regions deliberately such that the pictures of the gastrointestinal tract that are supplied are no longer random products. Consequently, the results of diagnosis can be much improved overall.
It may be remarked at this juncture that the aforesaid units, specifically transmitting unit, energy receiving and supply unit and locating unit can also be used separately of one another.
In a further preferred embodiment, the illumination element is a light-emitting diode. It is preferred to provide a number of light-emitting diodes that are arranged around the optics for uniform illumination of the pickup region.
On the one hand, light-emitting diodes are very compact components, while on the other hand they manage with relatively little energy in conjunction with a high light yield, something which renders them advantageous for use in an intracorporeal probe.
In a further preferred embodiment, an electroacoustic transducer is provided that generates an acoustic signal in the audible or in the ultrasonic range.
It is further preferred that in addition to the image sensor the image pickup unit has further electronic elements for processing the signals supplied by the image sensor.
This measure has the advantage that the image signals can be compressed, for example, even in the probe in order thereby to be able to lower the requisite data transmission rate or, vice versa, to be able to transmit more image data to extracorporeal space per time unit.
In a further preferred embodiment, the image pickup unit is arranged at a longitudinal end of the housing, and this end region of the housing is of dome-shaped and transparent design.
The arrangement of the image pickup unit at a longitudinal end has proved to be particularly advantageous with regard to the possible pickup region. However, it is to be remarked that the image pickup unit could also be arranged at other positions inside the probe. Moreover, it is conceivable that at least one further image pickup unit is provided in a movable fashion, for example in such a way that their pickup regions complement one another. For example, the image pickup units could be arranged such that—in the unswiveled state—their optical axes are perpendicular to one another.
This preferred refinement enables a further enlargement of the pickup region, and thus an improvement in the results of diagnosis, since more image information, for example from the gastrointestinal tract, is available to the examining doctor.
Further advantages and features emerge from the following description and the attached drawing. It goes without saying that the aforementioned features, and those still to be explained below, can be used not only in the respectively specified combination, but also in other combinations or on their own without departing from the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are illustrated in the drawing and will be described in more detail hereinafter with reference thereto, wherein:
FIG. 1 shows a perspective view of an intracorporeal probe according to the invention;
FIG. 2 shows a perspective illustration of the probe from FIG. 1 with partially opened housing;
FIG. 3 shows a perspective schematic diagram of an image pickup unit;
FIG. 4 shows a sectional schematic diagram of the image pickup unit from FIG. 3 ;
FIGS. 5A-C show a schematic diagram of the image pickup unit inside the probe for the purpose of explaining the inventive mobility of the image pickup unit;
FIG. 6 shows an exploded schematic diagram of the inventive probe;
FIG. 7 shows a perspective schematic diagram of a longitudinal section of the probe that contains the image pickup unit; and
FIG. 8 shows a schematic diagram of a further embodiment of the intracorporeal probe for the purpose of achieving the ability to rotate about the longitudinal axis.
DESCRIPTION OF PREFERRED EMBODIMENTS
An intracorporeal probe is shown in a perspective illustration in FIG. 1 and marked with the reference numeral 10 . This probe 10 is used, for example, to examine hollow organs or body cavities in the human or animal body. In particular, the probe is used to examine the gastrointestinal tract of a patient. The probe 10 is swallowed for this purpose by the patient to be examined and thereafter travels through the gastrointestinal tract, finally being excreted again.
The probe 10 is of elongated shape, the longitudinal axis being indicated by dashes in FIG. 1 , and being denoted by the letter L. The dimensions of the probe are selected such that the probe can be easily swallowed, and so they correspond approximately to the dimensions of conventional drug capsules.
The probe 10 has a dome-shaped longitudinal end 12 that is fabricated from an optically transparent material. By contrast therewith, the remaining part of the probe, which is denoted by the reference numeral 14 , is fabricated from a nontransparent material. The longitudinal end 12 and the longitudinal section 14 adjoining it together form a liquid-tight and acid-resistant housing 16 .
Visible in the region of the longitudinal end 12 behind the transparent dome is an optics 18 whose optical axis coincides in FIG. 1 with the longitudinal axis L. The optics 18 serves the purpose of focusing light from outside the probe onto an image sensor.
Provided in a fashion uniformly spaced around the optics 18 are illumination elements 20 , the illumination elements 20 preferably being designed as LEDs 21 . The LEDs 21 serve the purpose of illuminating a specific region outside the probe. The alignment of the LEDs 21 thus corresponds in essence to the alignment of the optics 18 .
The components provided inside the housing 16 are well in evidence in the illustration of FIG. 2 . Following the optics 18 is an image sensor 22 that is preferably designed as a CMOS sensor 23 . The image sensor 22 is seated, in turn, on a camera chip 24 that contains the logic circuitry required for evaluating the image signals supplied by the CMOS sensor.
The optics 18 , the image sensor 22 and the camera chip 24 together form an image pickup unit 26 . The aforesaid elements 18 , 22 and 24 are consequently permanently interconnected and therefore can be handled as a unit. The camera chip 24 is connected inside the housing to two points thereof, one connecting point being visible in FIG. 2 and denoted by the reference numeral 28 . The other connecting point (not visible) lies on an axis that goes through the connecting point 28 and cuts the longitudinal axis L. The connecting points 28 are designed such that a rotation of the camera chip 24 about a transverse axis Q (that is perpendicular to the longitudinal axis L and goes through the two connecting points 28 ) can be performed.
The entire image pickup unit 26 , that is to say also the image sensor 22 and the optics 18 , can be pivoted or swiveled about the transverse axis Q with the aid of this swiveling suspension of the camera chip 24 . The consequence of such a swiveling movement is a variation of the optical axis by comparison with the longitudinal axis L, and thus a variation in the pickup region sensed by the image pickup unit 26 .
Overall, the image pickup unit 26 is designed to sense a specific pickup region outside the probe, and supply the optical images of the pickup region to the examining doctor.
Following the image pickup unit 26 inside the probe 10 , as seen in the longitudinal direction, is a positioning motor 30 that is connected to the camera chip 24 via a coupling element 32 . The motor 30 is a rotary motor, for example in the form of a Q-PEM motor, a time motor or a piezomotor. The motor 30 and the coupling element 32 together have the task of swiveling the camera chip 24 , and thereby the image pickup unit 26 about the transverse axis Q. In the present exemplary embodiment, the rotary movement of the motor 30 is transformed via the coupling element 32 into a transverse movement. The coupling element 32 can be designed, for example, as a flexible shaft that is displaced in the longitudinal direction via a cam on the motor 30 .
Of course, the person skilled in the art is also familiar with other solutions that enable a swiveling movement of the image pickup unit 26 . For example, instead of the rotary motor 30 it would be possible to use a linear motor for swiveling the image pickup unit 26 .
Provided in the same longitudinal section as the motor 30 inside the housing 16 of the probe 10 is a locating chip 34 that can supply exact position information. A locating chip is described in detail as a position-detecting element for example in the application WO 03/024328 of the applicant, and so reference is made for the purpose of simplification to this printed publication and the corresponding disclosure content is incorporated by reference. The position-detecting means of the probe 10 can be designed, for example, as a coil system whose position can be detected via an external magnetic field detector.
Other solutions directed to locating, that is to say determining the position of the probe, for example inside the gastrointestinal tract, are, of course, also conceivable.
Following the locating chip 34 in the longitudinal direction is an energy and data transmission chip 36 that is responsible, on the one hand, for transmitting information from intracorporeal to extracorporeal space and, on the other hand, for receiving data, for example control signals, from extracorporeal space. Corresponding solutions for the transmission of such data are likewise described in the previously mentioned printed publication WO 03/024328. In addition, the chip is capable of receiving energy from extracorporeal space.
Finally, the probe 10 includes at least one battery 40 at the longitudinal end 38 opposite the longitudinal end 12 . This battery 40 is designed such that it can supply sufficient energy to the aforementioned electronic components inside the probe 10 .
The probe 10 usually contains additional coils that are not shown in the figures. These coils can be used to position the probe in the gastrointestinal tract by applying an appropriate magnetic field extracorporeally. The examining doctor can therefore control the position of the probe from outside.
All in all, the intracorporeal probe shown in FIG. 2 provides the examining doctor with a tool with the aid of which he obtains pictures of the gastrointestinal tract that are much more precisely targeted than has been possible to date using rigid image pickup units and position control solely by magnetic fields. A field of view of virtually 180° can be covered by swiveling the image pickup unit 26 . In order further to improve the image quality, the optics 18 can have an objective that is focusable and/or zoomable or can be switched to macrophotography. The focus can be set, for example, via a magnetic drive (not illustrated in FIG. 2 , however). The aforesaid preferred embodiment is of particular importance whenever the distance of the optics 18 from the inside of the dome-shaped longitudinal end 12 changes as a result of the swiveling movement of the image pickup unit.
Of course, other image sensors, for example CCD sensors, are also conceivable in addition to the abovementioned CMOS sensor 23 . However, an HDRC (High Dynamic Range Camera) image sensor based on CMOS technology has proved to be particularly advantageous in practice. Such a logarithmically operating sensor is described in detail in DE 42 09 536, and so reference may be made thereto.
FIGS. 3 and 4 show an image pickup unit 26 that differs somewhat with regard to its shape from the image pickup unit illustrated in FIG. 2 .
As already mentioned, the image pickup unit 26 comprises the camera chip 24 , which has electronic components for processing image signals. On this camera chip 24 , the image sensor 22 lies inside an interior 42 that is surrounded by a housing 44 . The housing 44 is fabricated from an opaque material such that light can pass into the interior 42 only through an opening 46 . Starting from the opening 46 , the interior 42 expands conically toward the image sensor 22 .
The upper longitudinal section 48 of the housing 44 also has this conical shape. The conical shape of the longitudinal section 48 enables a more effective possibility of swiveling inside the dome-shaped longitudinal end 12 of the probe 10 .
The optics 18 , which preferably includes a focusing objective, is provided in the opening 46 .
The optics 18 is designed such that a region lying directly before the dome-shaped longitudinal end is focused onto the image sensor 22 .
The LEDs 21 are arranged adjacent to the optics 18 , use being made of a total of four LEDs in the present exemplary embodiment. Of course, a different number of LEDs is also possible.
The swivelability of the image pickup unit 26 will now be examined again with reference to FIGS. 5A-C .
The image pickup unit 26 is shown in FIG. 5A in its fundamental position, in which the optical axis, denoted by O, coincides with the longitudinal axis L of the probe 10 .
The motor 30 must be activated if the image pickup unit 26 is to be swiveled about the transverse axis Q. A stepwise rotation of the motor 30 leads to a displacement of the coupling element 32 and, owing to the fact that it is fitted offset from the transverse axis Q, to a swiveling of the image pickup unit 26 . In FIG. 5B , the image pickup unit 26 is swiveled counterclockwise by an angle α, while in FIG. 5C the swiveling has been performed in a clockwise fashion by the angle α. The two maximum values of the angles α are preferably designed such that a pickup region of virtually 180° can be detected by the image pickup unit.
As already mentioned, the person skilled in the art is familiar with different solutions of achieving the above-described swivelability of the image pickup unit 26 about the transverse axis Q. The invention is not intended to be limited to the illustrated solution with a rotary motor and a shaft as coupling element.
In order to achieve swiveling of the image pickup unit 26 , it is preferred to control the motor 30 via control signals that are output by the examining doctor. Control signals can be received by the data transmission chip 36 and be processed to form control signals for the motor 30 . Of course, it is also conceivable to run the swiveling of the image pickup unit 26 via a permanently prescribed control program stored in the electronics of the probe 10 .
The images supplied by the image pickup unit 26 , preferably ten images per second, are processed by the logic circuitry on the camera chip 24 , in particular compressed in order then to be transferred to extracorporeal space for the purpose of visualization for the examining doctor. The processing of the image signals on the camera chip 24 can be taken over, for example, by an ASIC designed therefor.
The image information supplied to the examining doctor is linked to positional information that is supplied by the locating chip 34 . The examining doctor therefore has the possibility of assigning the image information obtained to a specific region, for example inside the gastrointestinal tract.
The energy required to supply the electronic components inside the probe 10 is supplied by the battery 40 . However, it is also conceivable for the energy, or at least a portion of the required energy, to be fed from outside. To this end, the energy and data transmission chip 36 can have three orthogonal coils and a stack of thick film substrates that fix and connect the receiver's electronic components. The three coils can be pushed into one another in order to form a compact cylinder that surrounds the electronic components. Because of the orthogonality of the coils, at least always one coil is capable of extracting energy from the external magnetic field independently of the position and alignment of the probe.
The probe of FIG. 2 is shown once again in another illustration in FIGS. 6 and 7 . Identical components are marked with identical reference numerals for the sake of simplicity. It is clearly to be seen from the two FIGS. 6 and 7 that the camera chip 24 , and thus the image pickup unit 26 overall, is rotatably fitted on the housing 16 via two connecting points 28 . Also to be seen are the cable connections 50 that run from the data transmission chip 36 to the camera chip 24 and the motor 30 . Also well in evidence is the dome-shaped longitudinal end 12 that is fabricated from a transparent material, preferably glass.
With reference to FIG. 8 , a further embodiment of the inventive intracorporeal probe 10 will now be described that differs from the previous probe only in that the image pickup unit 26 is also held in a fashion capable of rotating about the longitudinal axis L.
To this end, the motor 30 and image pickup unit 26 are held by a frame 52 that can rotate inside the housing 16 about the longitudinal axis L. For example, the frame 52 could comprise two rings 54 , 56 that are supported on the inside of the housing. The two rings 54 , 56 are interconnected via one or more elements 58 running in the longitudinal direction. The motor 30 is fastened on such a longitudinally running element 58 (longitudinal carrier) in the example shown in FIG. 8 .
The rotation of the frame 52 , and thus of the image pickup unit 26 , about the longitudinal axis L is performed via a second motor 60 , which is permanently connected to the housing 16 and, for example, cooperates with the ring 56 in order to rotate the frame 52 . Of course, other technical solutions can also be presented for the purpose, on the one hand, of holding the image pickup unit 26 and the motor 30 in a fashion capable of rotating about the longitudinal axis L, and, on the other hand, of undertaking the drive.
The rotatability of the image pickup unit 26 about the longitudinal axis L expands the possible pickup region in such a way that virtually the entire region about the dome-shaped longitudinal end 12 can be detected.
As also in the case of the motor 30 , the motor 60 is preferably controlled via control signals output from extracorporeal space. However, the motor 60 could also be controlled via a permanently prescribed program.
A single image pickup unit 26 is provided in the probe 10 in the previously described exemplary embodiments. However, it is also conceivable to provide the image pickup unit 26 additionally at the opposite longitudinal end such that the pickup region is much enlarged.
Finally, it is also conceivable to provide two swiveling image pickup units 26 at a longitudinal end of the probe 10 , or to provide an image pickup unit whose optical axis runs perpendicular to the longitudinal axis L and permits visual detection of the region at the lateral housing 16 .
The inventive intracorporeal probe could also be combined with a probe such as is disclosed in the printed publication WO 03/024328 already previously mentioned.
It may be stated in summary that a substantial improvement is possible, in particular with regard to the targeting accuracy of the imaging, with the aid of the inventive swiveling arrangement of the image pickup unit 26 | The invention relates to an intracorporeal probe ( 10 ), for example preferably for examining hollow organs or natural or artificially created body cavities in the human or animal body, the probe ( 10 ) being designed in the form of a capsule that can be introduced into the body without external connecting elements, comprising an elongate housing ( 16 ) and an image pickup unit ( 26 ) inside the housing ( 16 ) that is designed for optically recording a region (pickup region) outside the probe ( 10 ). The image pickup unit ( 26 ) is held in a fashion capable of moving inside the housing ( 16 ) in order to vary the pickup region by means of such a movement (FIG. 1 ). | 0 |
This application is a divisional of application application Ser. No. 08/997,321 filed on Dec. 23, 1997, and now U.S. Pat. No. 5,930,855.
BACKGROUND OF THE INVENTION
The present invention relates to laundry appliances, particularly clothes washing machines. More particularly, the present invention relates to a device and method for optimizing the rotational speed of a washing machine tub during the spin cycle so as to minimize washing machine vibration.
A tuned vibration absorber mounted to a clothes washer has been found to effectively reduce machine vibration. The vibration absorber is tuned to reduce machine vibration when the tub is rotated over a range of speeds and is most effective when it vibrates out of phase with the vibration of the washing machine. Such a vibration absorber is described in applicant's co-pending application Ser. No. 08/996,755, filed Dec. 23, 1997.
One difficulty with a vibration absorption system is that the tuned frequency of the absorber is dependent upon the mass attached to the absorber, the spring rate of the springs, the amount of clothes in the tub of the washing machine, floor conditions, and other installation conditions. Consequently, the optimum operational rotational speed for the tub varies from machine to machine, installation to installation and cycle to cycle. Thus, it is not sufficient to preset the controls of the washing machine to spin the tub at a certain rotational speed. For these reasons, there is a need for a device and method of determining the optimum rotational speed of the tub during each spin cycle to best utilize the vibration absorber and minimize machine vibration.
A general object of the present invention is the provision of an improved automatic washing machine.
A further object of the present invention is the provision of an automatic washing machine which determines the optimum rotational speed for the tub during each spin cycle.
A further object of the present invention is the provision of a method for determining the optimum rotational speed for the tub during each spin cycle.
A still further object of the present invention is the provision of a method for quickly determining the optimum rotational speed of the tub to minimize machine vibration.
These as well as other objects, features and advantages of the present invention will become apparent from the following specification and claims.
SUMMARY OF THE INVENTION
The present invention relates to a method and apparatus for optimizing the rotational speed of a washing machine tub during the spin cycle to minimize machine vibration. The method includes sensing and recording rotational speeds and machine vibrations over a range of rotational speeds to quickly determine the optimum speed. The method preferably includes a period of accelerating the washing machine tub to first locate a maximum vibration value and then an approximate minimum vibration value before the tub is decelerated towards the minimum value to more accurately select a rotational speed which minimizes washing machine vibration. The apparatus includes a variable speed washing machine and an accelerometer to sense machine vibration. The washing machine preferably includes a micro-processor, data storage memory circuitry, and computer software to analyze machine vibration and select an optimum speed to minimize machine vibration.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a washing machine used with the present invention.
FIG. 2 is an enlarged perspective view of an accelerometer used to sense machine vibration during the spin cycle.
FIGS. 3A and 3B show a flow chart of the preferred method used to optimize rotational speed and machine vibration.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be described as it applies to its preferred embodiment. It is not intended that the present invention be limited to the described embodiment. It is intended that the invention cover all alternatives, modifications, and equivalents which may be included within the spirit and scope of the invention.
FIG. 1 shows a clothes washing machine 10 having a tub 12 mounted within an enclosure 14. A multi-direction vibration absorber 16 is mounted inside the front door 18 adjacent the tub 12. To practice the invention, it is important that the tub 12 be capable of rotating at different speeds. Thus, a variable speed motor (not shown) is provided to rotate the tub 12. Although FIG. 1 shows a horizontal-axis washing machine, the present invention is also suitable for use with conventional vertical-axis washing machines.
The multi-direction vibration absorber 16 is tuned to vibrate in response to certain frequencies. The vibration absorber 16 comprises generally a mass suspended in the door 18 by a plurality of springs as shown in FIG. 1. The vibration absorber 16 is most effective at absorbing and controlling vibration when it vibrates out of phase with machine vibration. The details of the vibration absorber are disclosed in co-pending application Ser. No. 08/996,755, filed Dec. 23, 1997, which is incorporated by reference.
A control 20 is mounted within a console 22 for controlling the operation of the washing machine 10. An accelerometer 24 as shown in FIG. 2 is interfaced with the control 20 and is used to sense machine vibration. Although the accelerometer 24 can be positioned in a variety of different locations about the washing machine 10, mounting the accelerometer 24 towards the top of the washing machine 10 has been found to produce the most reliable measurements.
As shown in FIG. 2, the accelerometer 24 used with the present invention includes a piezoelectric film 26 with a mass 28 attached to the end of the film 26. The accelerometer 24 is well-suited for measuring vibration, as acceleration and vibration are proportional.
The control 20 of the preferred embodiment uses an 8-bit register to store vibration values to display an integer between 0-255 as a measurement of vibration. The control 20 also houses a micro-processor, data memory circuits and computer software.
A method is provided for determining the optimum rotational speed of the tub 12 at which machine vibration is at a minimum. In general, the computer software program interfaces with the control 20 to direct and monitor the rotational speed of the tub 12. The program reads vibration inputs from the accelerometer as the tub is accelerated over a range of rotational speeds. The program then, based on a comparison of the different vibration measurements, quickly and accurately identifies a range at which vibration is a minimum and directs the variable speed motor to decelerate the tub and focus around this minimum range. After more closely monitoring vibration about the minimum vibration range, the program then directs the variable speed motor to settle in at and maintain a rotational speed at which machine vibration is at a minimum.
The method which has been found most effective in quickly and accurately determining an optimum rotational speed so as to minimize machine vibration is set out in FIGS. 3A and 3B. To aid in the description of the prepared method, each of the nodes are identified by a reference numeral. First, the computer software program monitors whether the washing machine 10 is in the spin cycle (32). Once the washing machine 10 enters the spin cycle, then the variable speed motor is activated to start and accelerate the tub 12 spinning (34). Parameters required for determining optimum values for rotational speed (S) and vibration (V) are initialized (36).
The program then continues to monitor the rotational speed (S) of the tub 12 until it reaches a threshold level (S i ) (see 38, 40 and 42). Experimentation has shown 740 rpm to be a suitable S i under normal conditions. Once the tub 12 reaches this threshold speed (S i ), then vibration values (V) from the accelerometer 24 are read (44). This initial reading sets both initial maximum and minimum vibration values (V max , V min ) (46). The program will continue to update these values as it searches for a final value as described in detail below.
The preferred method first searches for a maximum vibration value (V max ). As acceleration continues, vibration is constantly read and recorded to establish the current maximum vibration value (V max ) (see 48, 50, 52, 54 and 56). The current vibration value (V) is always compared with a maximum vibration value (V max ) which is repeatedly updated (54, 56).
The tub 12 continues to accelerate throughout this initial period while searching for a maximum vibration value. Often machine vibration will be at a maximum just prior to entering a range of minimum vibration; accelerating the tub 12 past these maximum values lessens the effect of these spikes in vibration.
The maximum vibration value (V max ) is used as a benchmark in testing for a minimum vibration value (V min ). The program recognizes a minimum vibration value (V min ) as a vibration value less than the previous V min and less than or equal to one-half of V max (58, 60).
Once the current vibration value (V) reaches a level equal to or greater than twice the minimum vibration value (V min ), or there has been no change in the minimum vibration value (V min ) for 20 rpm, then the program assumes that the tub 12 has accelerated past a true minimum vibration value (62). Once this condition is satisfied, the method begins to search for a more accurate V min and the speed with the minimum vibration value (V min ) (see generally FIG. 3B). During some cycles this condition may not be satisfied before the tub reaches the upper limit of its rotational speed (S f ). In this case, the tub 12 is decelerated from this upper limit S f to fine tune the minimum (V min ) (see 52, 53). That is, the tub 12 can be decelerated without first satisfying the minimum vibration condition if rotational speed reaches a predetermined value (S f ), preferably 850 rpm. It is also possible that the tub will reach an acceptable level of vibration (V a ) before an actual minimum vibration level is found. In this case, the searching method is cut short and the tub 12 set to spin at S a , the rotational speed corresponding to the acceptable level of vibration (V a ) (see 64, 66). In other words, when vibration is sufficiently low at a default high speed, preferably 810 rpm, then the program can break out of the optimization routine.
Tub 12 is incrementally decelerated while searching for a final minimum vibration value (V min ). That is, the tub 12 is stepped through certain rotational speeds in fine tuning the minimum vibration value (V min ). Rotational speed (S) and vibration (V) are recorded (76) as the tub 12 decelerates at increments of 5 rpm (84). The tub 12 is maintained at each increment for a sufficient time, preferably 5 to 7 seconds, to allow vibration to stabilize (74). Once a vibration reading is encountered which exceeds the continuously updated minimum vibration, then the tub is accelerated to the optimum rotational speed (S min ) and the corresponding minimum vibration level (V min ) (see 80, 86 and 88). This minimum vibration level corresponds to the rotational speed at which the vibration absorber 16 is at, or approximately, out of phase with machine vibration. Again, an acceptable vibration value (V a ) can be tested for to short cut the method (78). Also, the search can be stopped when the rotational speed reaches a threshold level (S f ) (78). This method of determining the optimum operational speed quickly reaches a desired setting without spending considerable time in ranges of high vibration.
It should be understood that this method is not dependent upon predetermined hard-coded values. For example, the threshold rotational speed (S i ), constants used to test for a true minimum vibration value (V min ), and rpm increments for decelerating the tub 12 can all be customized based on the size of the washer, type of vibration absorber, market requirements, installation conditions, etc.
It should also be understood that the method of the present invention may be used either with or without a tuned vibration absorber. In either case, the method finds an optimal speed to rotate the tub. | A method and apparatus for optimizing the rotational speed of a washing machine tub to minimize washing machine vibration. The washing machine uses an accelerometer to sense machine vibration. A computer software program monitors, records, and compares machine vibrations over a range of rotational speeds to determine a rotational speed which minimizes machine vibration. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to circuit for locking a signal to a d.c. reference value during successive time intervals so as to regularly restore a basic level of the signal. The present invention more specifically relates to such a control circuit allowing, in a television set, restoration of the black level of a chrominance or luminance signal after the line fly-back.
2. Discussion of the Related Art
FIG. 1 shows a conventional circuit for locking a luminance or chrominance signal to the black level. The unlocked signal V is applied to the input of an amplifier 10 via a capacitor C. The signal Vc at the input of amplifier 10 corresponds to the signal to be locked to the black level. Said signal Vc, amplified by amplifier 10, is most of the time converted into a digital signal by an analog-to-digital converter 12. A digital comparator 14 receives on an input A the digital output N of converter 12 and on an input B a reference digital value Nref. The terminal of capacitor C, from which the locked signal Vc is taken, is connected to a high supply potential Vdd by a charging current source Ic, and to the ground GND by a discharging current source Id. The charging source Ic is activated by a signal UP issued by comparator 14 when the value N is lower than Nref. The source Id is activated by a signal DN issued by comparator 14 when the value N is higher than Nref. The source Ic or Id is activated at the rate of a clock CK provided to comparator 14 and converter 12.
With this configuration, when the value N is higher than Nref, for instance, the source Id is activated and progressively discharges capacitor C. The voltage Vc decreases, and the signal N follows the evolution of the voltage Vc. When the signal N has reached Nref, none of the sources Ic or Id is activated, and the voltage Vc remains at the value reached.
This circuit is only used during line fly-back; the current sources Ic and Id are deactivated for the duration of the lines.
During a locking phase, the voltage V is assumed to be constant. In practice, this voltage V includes noise caused by various surrounding parasitic phenomena. The noise is directly transmitted by capacitor C and amplifier 10 to the input of converter 12 and can cause an alteration of the digital signal N. The noise, which is random and has a mean value equal to zero, is not a nuisance in an open loop, that is, outside the locking phases.
However, during the locking phases, the circuit performs a correction of the signal N at each clock cycle according to the value of the signal N found at the previous cycle. Thus, for instance, if a parasitic pulse of voltage Vc causes an increase of the value N, the circuit performs, at the next cycle, a negative correction on voltage Vc, even if said voltage Vc is simultaneously submitted to a negative parasitic pulse: the negative correction and the negative parasitic pulse cumulate and increase the error on the value N, rather than decrease it. Such cumulative errors have a non negligible probability of occurring and cause an oscillation of the signal N with an amplitude of several units. While a one unit oscillation is normal and tolerable, an oscillation of several units becomes apparent on the television screen and deteriorates the image quality.
Additionally, the converter 12 generally used in such a circuit is a converter which has a reaction time of several clock cycles CK, often three, between the time when a sample of the input signal of the converter is acquired and the time when the digital value of this sample is supplied by the converter. Thus, a charging or discharging current is applied to capacitor C during all these reaction cycles. If the value N only differs from Nref by one unit, the voltage Vc could reach the desired value during the first of the following reaction cycles. If this occurs, the correction nevertheless continues to be performed during the remaining reaction cycles, which draws the value Vc away from the desired value again. As the control is desirably performed quickly, relatively high charge and discharge currents are being used. Thus, this drawing away of the voltage Vc is likely to be sufficient to alter the value N in the wrong direction. There also results an oscillation of the signal N (and of the value Vc) with an amplitude which can become apparent on the television screen.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a circuit for locking a signal on a reference value, which has reduced sensitivity to noise.
Another object of the present invention is to provide such a circuit which does not start oscillating because of the reaction time of an analog-to-digital converter.
These objects are achieved in a circuit for locking an analog signal to a reference value, including an analog-to-digital converter receiving the analog signal modified by the charge stored in a capacitor. A digital comparator receives the output of the converter and a reference digital value, and controls capacitor charging and discharging sources. A memory point represents a stability condition flag for inhibiting the capacitor charging and discharging. A circuit for analyzing the converter output activates the flag when the successive values of the converter output meet a predetermined stability condition, and deactivates the flag when the successive values of the converter output meet a predetermined divergence condition.
According to an embodiment of the present invention, the circuit includes a window detector, which is active when the converter output is in the vicinity of the reference value, so as to reduce the amount of capacitor charging or discharging.
According to an embodiment of the present invention, the reduced amount of charging or discharging is such that the converter output varies by no more than one unit from a value to a following or successive value.
According to an embodiment of the present invention, the circuit includes a drift detector in order to apply a reduced amount of charging or discharging when the successive values of the converter output meet a predetermined drift condition and during the active time of said flag.
According to an embodiment of the present invention, the window of the window detector is delimited by the reference value increased by one and the reference value decreased by one.
According to an embodiment of the present invention, the stability condition corresponds to two consecutive values equal to the reference value, and the divergence condition corresponds to four consecutive values higher or lower than the reference value.
According to an embodiment of the present invention, the drift condition corresponds to three consecutive values higher or lower than the reference value, with the possibility that the second value among the three values is equal to the reference value.
The foregoing and other objects, features and advantages of the present invention will be discussed in the following description of specific embodiments, taken in conjunction with the accompanying drawings but not limited by them.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1, which has been previously described, shows a conventional circuit for locking a chrominance or luminance signal to the black level in a television set;
FIG. 2 shows an architecture of a locking circuit according to the present invention;
FIG. 3 shows a block diagram illustrating the operation of the circuit of FIG. 2 according to a first embodiment; and
FIG. 4 partially shows a block diagram illustrating the operation of the circuit of FIG. 2 according to another embodiment.
DETAILED DESCRIPTION
FIG. 2 shows some elements that are the same as in FIG. 1, referred to by the same reference numerals. The comparator 14 of FIG. 1 is replaced by a comparator 14' supplying, for example, an A≧B signal active if the value N is higher than or equal to Nref and an A=B signal active if the value N is equal to Nref. As an alternative, the comparator 14' further supplies an A=B+1 signal active if the value N is equal to Nref+1, and an A=B-1 signal active if the value N is equal to Nref-1. These four signals are supplied, according to the invention, to a control circuit 16 which analyses these signals and controls the current sources Ic and Id (by means of the signals UP and DN) in the manner described hereafter.
As a summary, according to a first embodiment, the circuit of FIG. 2 initially functions as that of FIG. 1, as long as the control circuit 16 detects a difference between the values N and Nref. As soon as the signal N settles on Nref, the control circuit 16 enters a locked mode where the sources Ic and Id are no longer activated. In this case, even if the signal Vc or N varies randomly due to the noise, the circuit performs no correction which could make the signals Vc and N oscillate.
Of course, a correction must be performed if the signal Vc starts diverging, which could translate a discharging of capacitor C through a resistor or a parasitic influence. This divergence could also be caused by a normal variation of the unlocked voltage V. In fact, the control circuit 16 analyses the successive values of the outputs A≧B and A=B of comparator 14' in order to detect a divergence condition. If such a divergence condition is detected, the control circuit 16 switches to the unlocked mode and the errors are corrected again as in the circuit of FIG. 1.
According to a second embodiment, the outputs A=B+1 and A=B-1 of comparator 14' are used by the control circuit 16 to perform a fine correction when the value N is in the vicinity of Nref (between Nref-1 and Nref+1). Thus, the circuit has a fast convergence mode when the signal N is distant from Nref, and a fine convergence mode when the signal N differs from Nref by a unit. The fine correction is chosen to be small enough for the signal N not to vary during the reaction cycles of converter 12, which avoids oscillations of the signal Vc or N. As an alternative, this fine correction is further used when the control circuit 16, being in its locked mode, detects a low drift condition insufficient for switching modes.
FIG. 3 shows a block diagram illustrating more in detail the operation of the control circuit 16 according to the first embodiment. In the block diagrams described hereafter, a paragraph describing a block starts with the block reference number.
100. A new value of the signal N is expected.
102. The last values of N are analyzed in order to determine if they meet a stability condition. This stability condition is met, for instance, if the last two values of N are equal to Nref. In practice, the values of the A=B output of comparator 14' are analyzed, and not the values of N. In order to do this, for example, the A=B signal supplies a 2 bit shift register, which is validated for each new value N. Thus, if the two bits of the shift register are on 1, the stability condition is met.
104. If the stability condition is met, the circuit enters a locked mode indicated, for example, by a flag corresponding to the state of a memory point (a flip-flop).
106. The last values of N are analyzed in order to determine if they meet a divergence condition. This condition is met, for instance, if the last four values of N are either all Greater or all smaller than Nref. In order to do this, in practice, the last four pairs of signals (A≧B, A=B) of comparator 14' are analyzed. The divergence condition is met if the four pairs are all equal to (1,0) or to (0,0). The A≧B and A=B signals are supplied, for instance, to respective 4 bit shift registers, which are validated for each new value N. The shift register associated with the A=B signal is also used to perform the analysis of the stability condition in block 102.
108. If the divergence condition is met, the circuit enters the unlocked mode by no longer validating the flag which had been validated in block 104.
110. A checking of whether the value N is higher than or equal to Nref is performed, which amounts to checking if the A≧B signal is on 1.
112. In case of a positive result, a checking of whether the value N is equal to Nref is performed, which amounts to checking if the A=B signal is on 1. If it is so, the situation is an optimum stability situation and the circuit expects a new value N at block 100.
114. The value N is strictly higher than Nref. A checking of whether the circuit is in the locked mode is performed. In case of a positive result, the value N is slightly higher than Nref and the difference is only a parasitic phenomenon which does not require correcting. The circuit expects a new value N at block 100.
116. The circuit is not in the locked mode. In this case, the signal N is in a convergence phase and decreases towards Nref, or has reached Nref but starts diverging by increasing. The signal DN is activated during a clock cycle, which causes the discharging of capacitor C by the current of source Id of an amount determined by the current of the source Id, the period of the clock CK, and the value of the capacitance C.
Symmetrical operations are performed if the value N is lower than Nref. In block 114', as in block 114, a check is performed on whether the circuit is locked. In case of a positive result, no correction is performed and a new value N is expected at block 100. In case of a negative result, the signal UP is activated at block 116' during a clock cycle so as to charge capacitor C with a predetermined amount.
The blocks 102 to 108, which are used to put the circuit in the locked or the unlocked mode, have been integrated in the block diagram of FIG. 3. However, the corresponding operations can be performed separately, in parallel with the rest of the operations of the block diagram.
Due to the operating mode just discussed, the control circuit according to the invention does not correct random parasites of the signal Vc or N, once the signal N has reached Nref. The signal Vc or N is corrected again only if it exhibits divergence characteristics (several successive values higher or lower than the desired value).
FIG. 4 partially shows a block diagram from the block 110 of the block diagram of FIG. 3, illustrating an optimized operation of the locking circuit according to the invention. This block diagram includes all the blocks of FIG. 3, which will not be described again.
113. This block is interposed between blocks 112 and 114. The value N is strictly higher than Nref and a checking on whether it is equal to Nref+1 is performed. In case of a negative result, the operations continue, as described previously, at block 114 to perform, if necessary, a normal correction.
120. The value N is equal to Nref+1. A checking on whether the circuit is in the locked mode is performed.
122. The circuit is not in the locked mode. At this step, it either means that the signal N is converging by decreasing towards Nref and is in the vicinity of Nref, or that the signal N starts to diverge by increasing. A fine correction is then performed. The capacitor C is discharged by a reduced amount with respect to that of block 116. In order to perform this reduced discharging, for example, the signal DN is only activated during an alternation of the clock CK, that is, during a half period of the clock or even less if the clock duty cycle is chosen to be lower than 0.5. The optimum value of this reduced discharging is such that voltage Vc does not reach a value corresponding to Nref-1 during the reaction cycles of the converter. The oscillations due to excessive corrections performed in the vicinity of Nref are thus suppressed. Besides, a fast convergence is provided by blocks 114 and 116 when the signal N is far from Nref.
124. The circuit is in the locked mode and the value N is equal to Nref+1. A check is performed on whether the last values of N meet a positive drift condition which is not sufficient to trigger the unlocking of the circuit. This drift condition corresponds, for example, to three consecutive values equal to Nref+1, with the possibility for the middle one to be equal to Nref. In case of a positive result, a correction is decided, but a fine correction is performed at block 122. In case of a negative result, no correction is performed and a new value N is expected at block 100.
The operations just described correspond to the correction of values of N greater than Nref. The values of N lower than Nref are corrected in a symmetrical way. Thus, in a block 113', a checking is performed on whether the value N is equal to Nref-1 (which is indicated by the A=B-1 signal of comparator 14'). In case of a negative result, the operations continue at block 114' in the way described in the block diagram of FIG. 3. In case of a positive result, a checking is performed at block 120' on whether the circuit is in the locked mode. If the circuit is in the locked mode, a fine correction is performed at block 122', by increasing the charge of capacitor C by an amount smaller than at block 116'. If the circuit is in the locked mode, a check is performed at block 124' on whether the last values of the signal N meet a negative drift condition. In case of a positive result, a fine correction is performed in block 122', otherwise no correction is performed.
The present invention has mainly been described by means of block diagrams that those skilled in art can easily retranscribe, for example, in VHDL language in order to generate logic circuits performing the desired operations. In addition, the order of the blocks of the block diagrams can be changed without altering the functions described. For instance, block 112 can be positioned before block 110. Then, in block 110, a check is performed on whether the value N is strictly greater than Nref.
Of course, the present invention is likely to have various alterations and modifications which will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and the scope of the invention. Accordingly, the foregoing description is by way of example only and is not intended to be limiting. The invention is limited only as defined in the following claims and the equivalent thereto. | The present invention relates to a circuit for locking an analog signal to a reference value, including an analog-to-digital converter receiving the analog signal modified by the charge stored in a capacitor. A digital comparator receives the output of the converter and a reference digital value, and controls capacitor charging and discharging sources. A memory point is a stability condition flag for inhibiting the charging and discharging of the capacitor. A circuit for analyzing the converter output activates the flag when the successive values of the converter output meet a predetermined stability condition, and deactivates the flag when the successive values of the converter output meet a predetermined divergence condition. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of manufacturing an optical component by die molding, and particularly to a production method in which an optical component is molded integrally with a holder.
2. Related Art
An optical component (or, optical element) such as a lens is often used while being housed in a holding member (holder) made of a metal or the like. The function of an optical component may be impaired by stain or scratch, and hence it is difficult to handle an optical component. When a holder is previously disposed, it is not required to handle an optical component with directly contacting the component, also in a step of incorporating the component into a machine or the like, so that occurrence of stain or scratch can be reduced.
In an optical component having an optical element and a holder in which the optical element such as a lens is made of glass, a resin, or the like and fixed into the holder, the holder and the optical element may be separately produced and then fixed together by adhesion. Alternatively, such an optical component having a holder is sometimes produced by a method in which a blank for the optical element is pressurized and deformed in the holder, and an optical surface is formed simultaneously with press fixation to the holder (for example, JP-A-61-114822 and JP-A-3-265529).
FIGS. 1A through 1D show a conventional procedure in the production of an aspherical lens by such a molding method. Hereinafter, the identical components are denoted by the same reference numerals, and their description may be often omitted. As shown in FIG. 1A , first, a lower die 12 is incorporated in a cylindrical barrel die 10 with upward directing a molding surface 15 . In the lower die, a step 13 is formed, and a lower portion 14 has a larger diameter. A cylindrical inner sleeve 18 which is an auxiliary member is placed on the step 13 . In this state, first, a lens holder 130 made of a metal is inserted from an upper portion of the barrel die 10 , and placed at a predetermined position of the inner sleeve 18 . As shown in FIG. 1B , then, a lens blank 120 is inserted into a through hole of the lens holder 130 , and placed on the molding surface 15 of the lower die 12 .
The lens blank 120 is made of a glass material, and processed into a spherical shape as shown in FIG. 2A . The lens holder 130 has a cylindrical shape as shown in FIG. 2B , and comprises a through hole having a circular section shape. The inner diameter B of the through hole must be larger than the diameter A of the lens blank 120 . The relationship between A and B must be designed so that the lens after shaping is in close contact with the lens holder, and an excess of the blank is not produced.
In this state, as shown in FIG. 1C , an upper die 116 is inserted and lowered into the upper portion of the barrel die 10 to press the lens blank 120 which is softened by heating to a predetermined temperature. As a result of the above procedure, as shown in FIGS. 2A and 2B , a molded product 122 which is defined by the shapes of the lower and upper dies 12 , 116 and the lens holder 130 is formed. The molded product 122 is fixed to the lens holder 130 , but is not fixed to the lower and upper dies 12 , 116 which are previously subjected to a releasing process, and can be released from the dies.
After the molding process is completed, as shown in FIG. 1D , the upper die is removed away, and an aspherical lens 150 having a holder is taken out. A holder and a lens blank are newly prepared, and the same procedure is conducted, whereby an aspherical lens having a holder can be repeatedly produced. According to this apparatus, only the upper die is taken out, and the other members are not required to be reassembled. Therefore, the repeated production is enabled within a short time period.
The lens holder is usually transported onto the inner sleeve while being mechanically grasped or sucked by vacuum suction. The lens holder 130 has the through hole 136 . In order to mechanically grasp the lens holder, therefore, means such as that a tweezers-like grasping tool 160 grasps an outer peripheral portion 132 as shown in FIG. 3A , or that the tool outward pushes an inner peripheral portion 134 to hold the lens holder as shown in FIG. 3B is taken.
When vacuum suction is employed, a method such as that in which suction is conducted while a suction port 180 is in contact with a side face 132 as shown as shown in FIG. 3C , or that in which suction is conducted while the suction port is in contact with an end face 138 that is deviated from the center, and that has a small area is selected.
In the conventional method, the two transportation works of placing the lens holder onto the inner sleeve, and then transporting the lens blank to the lower-die surface in the through hole of the lens holder are required. Therefore, there is a problem in that the working efficiency is poor.
Each of the lens holder transporting methods shown in FIGS. 3A through 3D has a problem. In the method of FIG. 3A , the grasping tool 160 is placed outside the lens holder 130 , and hence a room for allowing the grasping tool 160 to pass must be formed between the outer diameter of the lens holder 130 and the diameter of the inner periphery of the barrel die. The upper and lower dies and the like must be correspondingly produced in a larger size, and the cost of the production apparatus is increased. In the method of FIG. 3B , the lens holder is unstably held, and therefore easily drops during transportation.
In the case where the side face 132 of the lens holder 130 is sucked as shown in FIG. 3C , the lens holder must be rotated by 90° in the barrel die, and inadequate placement of the lens holder 130 as shown in FIG. 4 easily occurs. In the case of FIG. 3D , the suction port 180 must be inserted in close proximity to the inner peripheral face of the barrel die. Therefore, it is necessary to provide a room for the insertion, and the holding becomes easily unstable. In this case also, consequently, the problem such as shown in FIG. 4 readily occurs.
SUMMARY OF THE INVENTION
The invention has been conducted in order to solve the problems. It is an object of the invention to provide a production method in which a blank for an optical element such as a lens blank, and a holder such as a lens holder can be taken simultaneously and stably into a molding die and installed correctly therein. It is another object of the invention to provide a production method in which a special space for taking a holder for an optical component into a molding die is not required, and hence the size of a production apparatus is prevented from being increased.
The method of manufacturing an optical component having an optical element and a holder attached to the optical element which is provided by the invention is basically implemented in the following steps: inserting a blank for the optical element into a through hole of the holder wherein the through hole has a narrowed portion at which the blank is prevented from passing through the through hole; sucking at least the blank from an upper side thereof in a state where the blank is inserted into the through hole; transporting the holder and the blank simultaneously to a molding device; placing the blank on a molding surface of the molding device; and heating and pressurizing the blank in the molding device so that the blank is deformed to obtain a predetermined optical surface and is press-fitted to an inner face of the holder.
According to the method, when only the blank is sucked to be lifted up, the blank is caught by the narrowed portion of the through hole of the holder, and therefore also the holder can be lifted up together. When the blank and the holder are sucked together, the blank does not slip off from the holder because the narrowed portion exists in the through hole of the holder.
Therefore, the blank and the holder can be taken simultaneously and stably into the molding device, and correctly placed. The outer diameter of a suction port can be made smaller than that of the holder, and hence a special space for inserting the suction port into the molding device is not necessary. In the specification, the upward means a direction opposite to the direction in which the gravitational force acts.
Preferably, the molding device is fixed, an auxiliary member having a through hole for fixing the holder to a predetermined position with respect to the molding surface is disposed on a molding die, and the transported holder is placed at a predetermined position on the auxiliary member.
According to the configuration, the blank and the holder which are simultaneously transported can be correctly placed at the same time on the fixed molding device and the auxiliary member, respectively, and an optical component having a holder in which the optical component is correctly fixed to a predetermined position of the holder can be easily produced.
The through hole of the holder has a circular section shape, a portion which protrudes toward a center of the through hole is disposed in a part of an inner peripheral face of the through hole, the section shape of the through hole in the portion is symmetric about the center, and a minimum value of a distance passing the center is smaller than a maximum value of an external shape of the blank.
In the case where the section shape of the through hole is circular, when the above-mentioned relationships are established, the blank does not slip off from the holder. When the through hole is centrosymmetric, the end face of the holder can be easily held to an approximately horizontal state in the case where the blank is sucked and lifted, and the blank can be correctly placed in the molding device.
Preferably, the blank is circular, cylindrical, or spheroidal. In the case where the blank has such a shape, when the optical element is axisymmetric as in a lens, a molded product which is in close contact with the holder is easily configured. Here, deformation which is in the order of a shape error caused by a usual molding process is not considered in the terms of shapes such as “circular.”
According to the manufacturing method of the invention, a blank for an optical element such as a lens, and a holder such as a lens holder can be taken simultaneously and stably into a molding device and installed correctly therein. Therefore, the production efficiency of an optical component having a holder can be improved. Only the blank placed in the through hole of the holder is sucked, and taken as it is into the molding device. Therefore, a special space for inserting a suction tool into the molding device is not required, and the size of a molding device can be prevented from being increased.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A through 1D are views illustrating a conventional procedure in the production of a lens having a holder;
FIGS. 2A and 2B are views showing a conventional example of a lens blank and a lens holder;
FIGS. 3A through 3D are views showing conventional methods of transporting a lens holder;
FIG. 4 is a view illustrating problems in a conventional production method;
FIGS. 5A and 5B are views showing an example of a lens blank and a lens holder in the invention;
FIG. 6 is a view illustrating a method of transporting a lens holder and a lens blank in the invention;
FIGS. 7A through 7C are sectional views of a suction port of a sucking device;
FIG. 8 is a view of a molding device according to the invention;
FIG. 9 is a view showing a process of molding a lens in the invention;
FIGS. 10A and 10B are views showing other examples of the shape of the lens blank; and
FIGS. 11A and 11B are views showing other examples of the shape of the lens holder.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, a method of manufacturing an aspherical lens having a holder with using the production method of the invention will be specifically described.
A molding device used in molding of the lens is basically similar to the conventional apparatus shown in FIGS. 1A through 1D , and pressurizes a lens blank by two molding dies to deform it, thereby forming a lens as an optical element. Therefore, the molding surfaces of the molding dies are previously processed in accordance with the designed surface shape of an aspherical lens.
In a state before a lens blank and a lens holder are inserted, as shown in FIG. 1A , the lower die 12 (which constitutes a part of molding device) is inserted into the through hole of the cylindrical barrel die 10 , and disposed so that the molding surface 15 is directed in the upward direction. The lower die 12 is not moved during a molding process. The lower die 12 has a step 13 below the molding surface 15 . The sectional area of the lower portion 14 which is lower than the step 13 is larger than that of the upper portion having the molding surface 15 . The inner sleeve 18 which has a through hole, and which is an auxiliary member is placed on the step 13 . At this time, an upper portion of the lower die 12 is inserted into the through hole of the inner sleeve 18 .
In this state, the lens blank (blank) and the lens holder (holder) are loaded into the molding dies with using method which is a characteristic of the invention.
The lens blank 20 is made of a glass material, and previously processed into a spherical shape (having a diameter A) as shown in FIG. 5A .
The used lens holder 30 is made of a metal material and cylindrical as shown in FIG. 5B , and has a through hole having a circular section shape. In order to allow the lens blank to be inserted only, the shape of the conventional example such as shown in FIG. 2B may be used. In order to employ the production method of the invention, the through hole of the lens holder 30 must be partly narrowed so that the lens blank cannot pass therethrough.
In the example of FIG. 5B , an inward protruding portion 33 is disposed so that the diameter of the through hole is reduced in one end portion, or a portion of the through hole is narrowed so as to be smaller than the other portion. When an article which is molded into a spherical shape of a diameter A as shown in FIG. 5A is used as the lens blank 20 , the diameter C of the narrowed portion in the through hole of the lens holder 30 is made smaller than the diameter A of the lens blank 20 (C<A). Of course, the diameter B of the through hole in the portion into which the lens blank 20 is to be inserted must be larger than the diameter A of the lens blank.
The lens blank 20 and the lens holder 30 are prepared while being placed on a pallet 70 as shown in FIG. 6 . The pallet 70 has plural recesses or hole portions 72 in each of which a step is formed between a part for supporting the spherical lens blank 20 and that for supporting the lens holder 30 , so that plural lens blanks and lens holders can be held while being placed on the pallet. As shown in FIG. 6 , the lens holder 30 is placed on the pallet while the narrowed side of the through hole is positioned in the upper side so as to cover the spherical lens blank 20 .
By arranging plural pairs of the lens blanks 20 and the lends holders 30 on the pallet 70 in a state that each lens blank 20 is inserted in the through hole of the corresponding lens holder 30 . By such the preparation with the pallet 70 , continuous manufacturing of a large number of the optical components can be performed.
In the initial stage of the molding step, the lens blank 20 and the lens holder 30 which are on the pallet are simultaneously transported into the molding device. The transportation is conducted by means of suction. As shown in FIG. 7A , a suction port 80 of a sucking device has a flat end face 82 having a required perpendicularity. In the case where the suction port 80 having an outer diameter which is substantially equal to the outer diameter of the lens holder 30 as shown in FIG. 7B is used, the lens blank and lens holder are sucked together. Even when such suction is conducted, the lens blank 20 does not slip off from the lens holder 30 because the upper end of the through hole of the lens holder is narrowed.
In the case where a suction port 84 having an outer diameter which is smaller than the diameter of the through hole of the lens holder is used, only the lens blank 20 is sucked. Even when only the lens blank 20 is sucked to be lifted, the lens holder 30 is caught by the lens blank 20 and does not drop, because the upper end of the through hole of the lens holder 30 is narrowed.
In both the cases, the lens blank 20 and the lens holder 30 can be simultaneously moved to a predetermined position inside the barrel die 10 as shown in FIG. 6 . When the suction is cancelled at this position, or when a process of back blow is conducted in some cases, the lens blank 20 and the lens holder 30 are separated from the end face of the suction port 80 . As a result of the above, the lens blank 20 and the lens holder 30 are set simultaneously and accurately to predetermined positions on the molding surface of the lower die 12 and the inner sleeve 18 , respectively.
Thereafter, an upper die (second molding die) 16 is inserted and lowered into the barrel die 10 with downward directing the molding surface as shown in FIG. 8 . The lens blank 20 is heated to a temperature at which the blank is softened, and pressurized between the upper and lower molding dies 16 , 12 . When the volume of the lens blank 20 is previously set to a predetermined value, the lens blank 20 is deformed by the pressurization, with the result that a molding product 22 is obtained which is in close contact with the inner peripheral face of the lens holder 30 , and which is molded into the surface shape of an aspherical lens defined by the molding surfaces of the molding dies as shown in FIG. 9 .
FIG. 9 shows molding of a plano-convex lens in which the molding surface of the lower die 12 is aspheric and that of the upper die 16 is flat. However, this is only a example. Alternatively, the lower die may have a flat face, and the upper die may have an aspheric face, or the both faces of the lens may be convex.
After the molding product 22 is formed and press-fitted to the lens holder 30 , the molding product 22 is sucked and removed from the barrel die 10 . Such a sucking transportation is conducted in a similar manner to the transportation of the lens blank 20 and the lens holder 30 into the barrel die 10 as shown in FIGS. 6 and 7 . Since the molding product 22 has been integrated with the lens holder 30 , even when only the molding product 22 is sucked to be lifted, the lens holder 30 is secured to the molding product 22 and does not drop.
The above-described embodiment can attain the following effects.
(1) The vacuum condition which enables the suction operation is obtained by closing the through hole of the lens holder with the lens blank. At the same time as the lens blank, the lens holder can be sucked in the direction toward the through hole. Therefore, the lens blank and the lens holder can be simultaneously transported. (2) Since the outer diameter of the end face of the suction port can be made equal to or smaller than that of the lens holder, a space into which the lens holder can be inserted is sufficient for enabling transportation and insertion. (3) In the suction process, positioning and fixation are enabled by butting the end face of the suction port against that of the lens holder. Therefore, high accuracy can be achieved in the position and inclination in the case where the lens holder is set in the molding dies.
The production method can be applied also to an optical component having a holder, other than an aspherical lens and a spherical lens. Examples of such an optical component are a Fresnel lens having a minute concave and convex structure, a diffractive optical element such as a diffraction grating, and a prism.
The shape of the blank is not restricted to a spherical shape, and may be a cylindrical shape or a disk-like shape shown in FIG. 10A , a spheroidal shape shown in FIG. 10B , or the like. In this case, the diameter of the cylinder or the disk is considered to be equivalent to the diameter A of the sphere shown in FIG. 5A , and the diameter C of the through hole in the narrowed portion of the holder shown in FIG. 5B is requested to satisfy the relationship of C<A. In the case of a spheroid, the maximum width is considered as A, and then the same is applicable.
The section shape of the through hole of the holder is not always necessary to be circular, depending on the shape of the optical element to be held. In order to conduct the pressure molding, however, it is preferable that the section shape is centrosymmetrical.
The narrowed portion of the through hole is not always necessary to have a similar shape as the section of the other portion of the through hole as in the case of the holder 30 shown in FIG. 5B . The through hole is requested to have a structure in which the blank cannot linearly pass through the through hole in at least one direction.
For example, as in the case of a holder 230 shown in FIG. 11A , plural convex portions 233 protruding toward the center may be disposed on the inner peripheral face of through hole so as to be symmetrical about the center of the through hole. The minimum value of the distance between the tip ends of the convex portions, i.e., the distance passing the center is indicated as D. When the relationship of D<A is satisfied, the blank cannot pass through the through hole. Alternatively, as in the case of a holder 330 shown in FIG. 11B , an opening 333 may have a square section shape. Also in the alternative, when the minimum value of the distance of the square opening passing the center of the through hole is indicated as E, E is requested to satisfy the relationship of E<A.
Other shapes may be employed as means for narrowing the through hole. In order to prevent the blank from being inclined or positionally displaced, a shape which is symmetric about the center of the through hole is preferably employed. | A method of manufacturing an optical component having an optical element and a holder attached to the optical element, comprising the steps of: inserting a blank for the optical element into a through hole of the holder wherein the through hole has a narrowed portion at which the blank is prevented from passing through the through hole; sucking at least the blank from an upper side thereof in a state where the blank is inserted into the through hole; transporting the holder and the blank simultaneously to a molding device; placing the blank on a molding surface of the molding device; and heating and pressurizing the blank in the molding device so that the blank is deformed to obtain a predetermined optical surface and is press-fitted to an inner face of the holder. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is the formal patent application for provisional application Ser. No. 61/201,444, filed Dec. 10, 2008, entitled “Ultra-short Slip and Packing Element System”. Applicant hereby claims priority from said application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to downhole tools for oil and gas wells and similar applications and more particularly to improved well packers, plugs, and the like.
2. Description of Prior Art
Well packers are used to form an annular barrier between well tubing or casing, to create fluid barriers, or plugs, within tubing or casing, or the control or direct fluid within tubing or casing. Packers may be used to protect tubulars from well pressures, protect tubulars from corrosive fluids or gases, provide zonal isolation, or direct acid and frac slurries into formations.
Typical well packers, bridge plugs, and the like, consist of a packer body. Radially mounted on the packer body is a locking or release mechanism, a packing element system, and a slip system. These packers tend to be two feet or longer depending on the packer design. The packing system is typically an elastomeric packing element with various types of backup devices. The packing system is typically expanded outward to contact the I.D. (internal diameter) of the casing by a longitudinal compression force generated by a setting tool or hydraulic piston. This force expands the elastomer and backups to create a seal between the packer body and casing I.D. This same longitudinal force acts through the sealing system and acts on the slip system. The slip system is typically an upper and lower cone that slides under slip segments and expands the slip segments outwardly until teeth on the O.D. (outer diameter) of a series of slip segments engage the I.D. of the casing. Teeth or buttons on the O.D. of the slip segments penetrate the I.D. of the casing, to secure the packer in the casing, so the packer will not move up or down as pressure above or below the packer is applied. A locking system typically secures the seal and slip systems in there outward engaged position in order to maintain compression force in the elastomer and, in turn, compression force on the slip system. Certain part configurations allow the locking mechanism to disengage to allow retrieval of the packer. The presence of the release mechanism usually classifies the packer as a “retrievable packer” and the absence of the release mechanism classifies the packer as a “permanent packer”.
Problems with prior art packers, in some cases, can be the excessive length of the packers since all of the above combined systems require length. An increased length of the tool results in an increased effort to mill or drill out the tool if and when necessary, particularly at the end of the useful life of the tool. It would advantageous to have a packer that is much shorter in that reduced material would certainly lower material and manufacturing costs. It would be advantageous to have a very short packer, so if packer removal is required, milling time would be greatly reduced.
Some of the drillable frac plugs on the market are the Halliburton “Obsidian Frac Plug”, the Smith Services “D2 Bridge Plug”, the Owen Type “A” Frac Plug, the Weatherford “FracGuard”, and the BJ Services “Phython”. By comparison, all of these plug designs are very long in comparison to the current invention. Also, a very short packer would reduce cost and simplify the task of creating a “Pass-through” packer. “Pass-through” packers are used for intelligent well completions and allow the passage of, for example and not limited to, hydraulic control lines, fiber optic lines, and electrical lines.
Both retrievable and permanent packers are sometimes drilled or milled out of the casing. If the packer is being used as a “Frac Plug”, it is commonly milled out after the frac is completed. Typical packers, as described above, tend to have mill-out problems because the packer parts tend to spin within the engaged slips. The mill operation becomes very inefficient because the packer parts spin with the rotation of the milling tool. Some packer designs exist, for example the BJ Services U.S. Pat. No. 6,708,770, to reduce this spinning tendency. It would be advantageous to have a packer design that would offer alternative features to prevent spinning of parts while milling out. It would also be advantageous if this same design feature would provide a means to equally distribute the slip segments around the packer body to evenly distribute the load on the I.D. of the casing, and also function as packer retrieval devices to retain and retract the slip segments during retrieving.
Another problem is that the slip system is loaded through the packing element system. Any degradation or extrusion of the packing element system reduces stored energy in the slip system thus allowing the slip system to disengage, especially during pressure reversals, the casing and in turn cause packer slippage and seal failure.
Typical packers have a seal system that has elastomers backed up by anti-extrusion devices and the anti-extrusion devices are backed up by gage rings. The gage rings typically have a built-in extrusion gap between the O.D. of the gage ring and the I.D. of the casing to provide running clearance for the packer. The built-in extrusion gap can be a problem and is commonly the primary mode of seal system failure at higher temperatures and pressures. This is because the elastomers and backup devices tend to move into the extrusion gaps. When this movement occurs, the stored energy is lost in the seal system and the seal engagement is jeopardized to the point of seal failure. It would be an advantage to remove the majority of the extrusion gap to prevent the seal from extruding or moving. Attempts have been made to reduce the extrusion gap by use of expandable metal packers, for example, the Baker expandable packer U.S. Pat. No. 7,134,504 B2, US 2005/0217869, and U.S. Pat. No. 6,959,759 B2, or the Weatherford Lamb metal sealing element patent #US 2005/023100 A1.
Typical retrievable packers have slip systems that, when expanded, contact the I.D. of the casing at 45 degree or 60 degree increments around the I.D. of the casing. Each slip segment has a width and there is typically a space between each slip segment. The space between each slip segment creates a surface area where no slip tooth engagement occurs. The total slip contact with the I.D. of the casing may, for example, only be 50% of the surface area on the inside of the casing. If pressure is applied across the packer, the slips are driven outward into the casing. It is a problem in that due to the incremental contact on the I.D. of the casing, high non-uniform stresses in the casing wall can cause deformation or even failure of the casing wall. It would be very desirable to have a slip system that approaches a full 360 degree contact in the I.D. of the casing to minimize damage to the casing. Also, with slip engagement approaching 360 degrees, there is more slip tooth engagement due to increased radial surface contact area, thereby providing the opportunity to reduce length of the slip. Reduced length of the slip then reduces the overall length of the packer.
Typical permanent packers have slip systems that “break”. Slips that “break” approach the 360 degrees of contact. These slips are usually made by manufacturing a ring, cutting slots in the ring to create break points, and then treating the teeth on the O.D. of the ring for hardness purposes. When longitudinal load is applied to a cone, the cone moves under the slip ring and the ring tends to break at the slots to create slip segments. History has shown that the slip segments, break unevenly or don't break at all, break at different forces, and engage the I.D. of the casing in irregular patterns. These breaking problems can reduce the performance and reliability of the packer. It would be advantageous to have slips that approach the 360 degrees of contact and are not required to break, don't require a variable force to break, and evenly distribute themselves around the I.D. of the casing.
Some packers have built-in “boosting” systems. Boosting systems exert additional force on packer seal systems when differential pressure is applied from either above or below, or both, relative to the packer. The additional boosting force tends to help the packer maintain a seal with the I.D. of the casing. The boosting systems typically added to packers require additional parts that add complexity to the packer and require the use of additional seals. Additional seals increase the risk of packer leaks if the seal should fail.
It would be advantageous to have a packer slip/seal design that inherently provides a seal and slip boosting feature, without additional seals and parts, when pressure is applied from either above or below the packer and in which design the slips and seals are arranged in a manner to provide sufficient well sealing and anchoring with component parts which are considerably shorter than those found in conventional packers and similar well plugs.
SUMMARY OF THE INVENTION
A tool is provided for sealing along a section of a wall of a subterranean well. The wall may be uncased hole or the internal diameter wall of set casing inside the well. The tool is carriable into said well on a conduit. The conduit may be any one of a number of conventional and well known devices, such as tubing, coiled tubing, wire line, electric line, and the like, and moveable from a run-in position to a set position by a setting tool manipulatable on or by said conduit. The tool comprises a plurality of anchoring elements, sometimes referred to as slips with a set of profiled angularly positioned teeth around the exterior for biting engagement into the wall of the well upon setting of the tool. The tool is shiftable from a first retracted position when the well tool is in a run-in position to a second expanded position after manipulation of the setting tool. The tool also includes seal means, preferably made of an elastomeric material, but may be metallic, or a combination thereof, which are carried around the anchoring elements for sealing engagement along the wall of the well in concert and substantially concurrently with the anchoring elements when the anchoring elements are shifted to the set position.
Stated somewhat differently, the tool of the present invention provides a packer device including an interior packer body and radially surrounding cone, slip and seal system that seals and engages the surrounding casing or other tubular member. The cones expand both the seal system and the slip system simultaneously. The slip system provides a means for supporting the seal system when pressure is applied from above or below the packer. The close proximity of the seal and slip system provides for a very short packer or a “minimum material packer” that offers lower cost, higher performance, and if required, faster mill-out.
The seal system can be of several configurations and one such configuration is an expandable metal seal combined with an optional elastomeric or non-elastomeric seal for high temperature and pressure applications.
This invention also provides an improved packer for cased or uncased wells or for a tubular member positioned inside of casing. A very short and simple packer design, with features that increase overall packer reliability, is created by effectively combining synergies of the cone, slip and seal elements to work in unison.
This packer can be set on standard or electric wireline, or with hydraulic setting tools conveyed on jointed pipe or coiled tubing.
The packer can be ready modified to serve several applications. A hydraulic setting cylinder can be added so the packer can be run as part of the casing or tubing. The packer can utilize a fixed frangible disc or a flapper device to serve as a bridge plug, frac plug, or frac disc-type of component.
The materials of the packer can be optimized to reduce mill-out time. Mill-out time is greatly reduced due to the very short length of the packer, typically, 3″ to 4″, so expensive composite materials aren't necessarily required, 3) a seal bore can easily be attached to the packer body. Since the slip system creates a metal-to-metal interface with the I.D. of the casing, the packer can readily be adapted to a high pressure and temperature well environment. The packer can address applications as simple as low cost plug and abandonment to highly complex applications in hostile environment wells. Finally, the packer, due to it's short length, is ideal for incorporating “control line pass-thru” for intelligent well completions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the present invention in the “running position”.
FIG. 2 is a schematic view of the present invention in the “set position”.
FIG. 3 is a cross-sectional view of the packer mandrel and slip segments of the present invention in the fully expanded “set position”.
FIG. 4 is a close-up quarter-section view of the packer mandrel lugs inside of a slip segment pocket in the “running position”.
FIG. 5 is a schematic of the present invention with a “flapper valve” attached.
FIG. 6 is a schematic of the present invention with a “seal bore” attached.
FIG. 7 shows two examples of the present invention in the “set position” inside of a section of casing with a workstring placing fluid into the formation above a set packer.
FIG. 8 shows a schematic of the present invention with a control line pass-thru added.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1 , a schematic of the present invention shows a 180 degree cross-section of the packer. A mandrel 1 has a running thread 16 with a separation recess 17 immediately below the running thread. Seal 11 is located on the O.D. of the mandrel 1 . At the bottom of the mandrel are an internal thread 18 and a seal 13 . A setting tool (not shown) is made up to running thread 16 in order to convey the packer into the well. A millable, frangible or disintegrable disc 14 is a fluid barrier and is threaded into thread 18 and seals on seal 13 . Cone surface 3 is shown of the O.D. of the mandrel 1 .
Lower seals 7 and 8 are shown to be positioned on cone surface 3 . Seal portion 7 is a deformable material but has sufficient rigidity to bridge the gap between slip segments 4 . Seal portion 8 is a deformable seal material that is fixably attached to seal portion 7 so that it can be reliably transported into the well. Rotational lock pin 12 is either attached to, or part of, mandrel 1 . The number of rotational pins is equal to the number of gaps between slip segments 4 . The rotational pins assist in positioning the slip segments equally around the mandrel and a modified version can act as a pickup shoulder if used in a retrievable packer configuration. The slip segments 4 are positioned almost 360 degrees around the O.D. of the mandrel 1 . Each slip segment has a series of teeth 19 , or some other casing penetrating profile, on the O.D. of the slip segment. The teeth are sufficiently hard to penetrate the inside of the casing wall in order to grip the wall and prevent the packer from moving relative to the casing. The slip segments have an O.D. that is machined to be almost equal to the I.D. of the casing. The slip segments are machined to minimize any gaps between the O.D. of the slip segments and the I.D. of the casing. Similarly, the angles on the I.D. of the slip segments are machined to almost match the O.D. of the cone surfaces 2 and 3 when the slip is fully expanded, in order to minimize gaps between the parts.
Seal 11 does not seal in the “running position” but in the “set position” seals on the I.D. of upper cone 15 . Upper seals 5 and 6 are the same as seals 7 and 8 . These seals, of course, can assume different geometries and materials based on the application of the packer. Upper and lower seals, 5 , 6 , 7 , 8 , are of sufficient strength to capture and retain slip segments 4 inward during the trip into the well.
Upper cone 2 has a surface 15 . The setting tool (not shown) pushes against surface 15 while pulling on threads 16 during the setting operation. Upper cone 2 has internal thread that engage body lock ring 9 . Body lock ring 9 can ratchet freely toward the slip segments 4 but engages and prevents movement away from the slip segments 4 by engaging the threads on the top O.D. of the mandrel 2 .
FIG. 2 shows the packer in the “set position”. In operation, the setting tool (not shown) pushes on surface 15 and pulls on thread 16 . Upper cone 2 moves toward the slip segments 4 and in the process expands the slip segments 4 and the deformable seals 5 , 6 , 7 , and 8 . Expansion continues until sufficient contact is made with the I.D. of the casing to achieve slip tooth 19 penetration in the inner wall of the casing. At this point the teeth of the slip segments have nearly closed any seal extrusion gaps between the O.D. of the slip segments and the I.D. of the casing. Extrusion gaps have been minimized nearly 360 degrees around the packer. Additionally, slip load has been nearly evenly distributed around the I.D. of the casing to minimize distortion of the casing. Slip segment 4 distribution around the O.D. of the mandrel 1 is more uniform due to the pins 12 . Also, extrusion gaps have been closed where the I.D. of the slip segments contact the surfaces of the cones at 20 and 21 . At his point the only extrusion gaps that exist are the ones between the slip segments. This can be seen in FIG. 3 identified as 31 . These extrusion gaps are blocked with the seal portions 5 and 6 that additionally minimize extrusion of seal portions 6 and 8 . The seals portions are expanded with the cones until surface 23 makes sufficient sealing contact with the I.D. of the casing. At this point the upper and lower cones have simultaneously engaged the slips and expanded the seals. Sufficient force is placed on the slips and cones to achieve tooth penetration and store seal compression. As a result, loss of seal compression does not create loss of slip tooth engagement and vise-versa. Furthermore, in the set position, all extrusion gaps have been closed to a minimum.
As the setting tool continues to stroke, body lock ring 9 ratchets on mandrel 1 until the slip segments and seals are fully energized. Lock ring 9 will not allow reverse movement to occur; therefore the packer is locked in the “set position”. In the FIG. 2 packer configuration, the setting tool continues to add force to the packer until a pre-planned tensile load is reached. This load is sufficient to shear the mandrel 1 at recess 17 so that ring 25 separates from mandrel 1 . Removal of ring 25 leaves a minimum amount of material to aid any milling operations that may be planned. Other methods of separation from the mandrel 1 are available depending on the application of the packer.
In the set position, FIG. 2 , when pressure is applied from below the packer, the cone surface 3 acts on the seal 7 and 8 and the slip segment 4 to further energize tooth engagement and the seals. Pressure from below acts on seals 7 and 8 to achieve a better seal. Conversely, pressure from above acts on seals 5 and 6 and cone surface 2 to achieve a better tooth engagement and seal pack-off.
FIG. 3 shows a cross-sectional view of the mandrel 1 and the slip segments 4 . Notice that lugs are protruding from the mandrel as indicated by the arrow labeled 1 and surface 28 . The lugs also have ears 29 that fit into the pockets 30 . The pockets 30 are shaped to allow the slip segments to move from the “run position” to the “set position” and back again. When the ears 29 touch surface 33 , the slip segments are trapped and can not expand further. This is a modification of the rotational lock pins 12 that are positioned between the slip segments. In this case some length, maybe 2 inches maximum, needs to be added to the slip segments. This configuration would apply more to a retrievable type packer where it is desired to retain the slips during retrieval. Referencing FIG. 4 , the mandrel lugs 1 are shown in a cross-sectional longitudinal view. During packer retrieval, lug surface 28 contacts slip segment surface 32 and pulls slip segment 4 off cone surface 3 . Of course, upper cone surface 2 is configured to move upward, when connected to a retrieving tool, from cone surface 3 to allow retraction of slip segment 4 . Simultaneously, the inner surface of ear 29 of the lug 28 , engages a lip 44 on the inside of the slip segment to retain the slip segment.
FIG. 5 shows a cross-section of the packer with the frangible disc removed from the bottom. Instead, a flapper valve 34 has been added to the top end of the packer. The flapper is hinged with pin 35 and seal on mandrel 45 at seal 36 . This configuration would allow treatment of the well above the packer and flow of the well from below at a later time without removing any flow barriers.
FIG. 6 shows the packer modified to be a seal bore packer. Seal bore 38 has been added to create a production packer that would allow installation of a production string (not shown). Seals (not shown) on the end of the production string are placed in the seal bore to direct fluid up the production string.
FIG. 7 shows well casing 39 in a formation 43 . The well casing 39 has two sets of perforations 41 and two packers 40 positioned between the perforations. A work string 42 places fluid, acid or proppant, into the formation. The packer 40 forces the fluid into the formation. Every time a zone is treated, a packer can be set, the formation treated, and then go to another zone up the hole if desired. When all zones are treated, the packers can be milled out prior to production. If milling is not desired, the frangible disc or flapper packer configuration can be used.
FIG. 8 shows the packer modified to serve as a “pass-thru” packer. The compact geometry of the slip and seal system reduces the length required to create a control line bypass through the body of the packer. This short distance can eliminate the expensive gun drill process that is usually needed to drill long holes through long packer bodies. FIG. 8 shows the same slip, seal and cone parts as in FIG. 1 . Drilled hole 46 provides a path for the control line, or fiber optic or electrical line to pass through the packer body. Fitting 47 acts as a fluid barrier between the hole 46 and the control line 47 . Thread 48 would be a typical connection on the packer to allow connection with the completion string (not shown). The top end of the packer is not shown for this example, but the top end of the packer would have some type of setting mechanism to stroke the packer to the set position.
Although the invention has been described above in terms of presently preferred embodiments, those skilled in the art of design and operation of subterranean well packers and the like will readily appreciate modifications can be made without departing from the spirit of the description and the appended claims, below. Accordingly, such modifications can be considered to be included within the scope of the invention disclosure and the claims. | A subterranean well tool seals along a section of a wall of the well and is carried on a conduit into the well. A plurality of anchoring elements and seals are provided for respective anchoring and sealing engagement along the wall of the well in concert and substantially concurrently with one another when the tool is shifted to the set position. When the well tool moves to the set position, a portion of the mandrel separates and is retrieved from the well bore, allowing the well tool to be reduced in overall length. The anchoring elements are sandwiched in between first and second, or upper and lower, sets of seals. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a U.S. national phase application under 35 U.S.C. §371 of International Patent Application No. PCT/JP2007/073036 filed Nov. 29, 2007 and claims the benefit of Japanese Application No. 2006-327638 filed Dec. 4, 2006 and Japanese Application No. 2006-327639 also filed Dec. 4, 2006. The International Application was published in the Japanese language on Jun. 12, 2008 as International Publication No. WO/2008/069089 under PCT Article 21(2). The contents of all foregoing applications are incorporated herein in their entireties.
FIELD OF THE INVENTION
The present invention relates to an excavating apparatus for underground excavation, a rotary excavator, and an underground excavating method.
In greater detail, the present invention relates to an excavating apparatus for underground excavation, a rotary excavator, and an underground excavating method that can perform excavation work with low levels of vibration and noise.
RELATED ART
In the fields of civil engineering and construction, excavating apparatuses called “down-the-hole hammers” are used in the excavation of hard soil foundations that principally contain, for example, bedrock, boulders, concrete, and the like. A down-the-hole hammer supplies compressed air to drive an internal piston, which moves a hammer bit at the tip up and down, and excavation is performed by the resulting strikes (e.g., refer to Japanese Unexamined Patent Application Publication No. H9-328983 (hereinafter “JP '983”, please refer to FIG. 1 thereof).
In addition, excavating apparatuses called “earth augers” that excavate holes using a helical cone are also used; however, compared with the abovementioned down-the-hole hammer, an earth auger is not as well suited to the excavation of a hard soil foundation that contains, for example, bedrock, boulders, or concrete.
In a conventional down-the-hole hammer as shown in FIG. 1 of JP '983, the soil foundation is struck by moving a hammer bit, whose diameter is substantially the same as that of the hole to be excavated, up and down; consequently, the impact to which the soil foundation is subjected with every strike is large, which generates intense noise and vibrations during excavation. Consequently, the conventional down-the-hole hammer is not suited for use in, for example, dense residential areas and urban business districts where it is preferable to perform work with low levels of vibration and noise.
Thus, in locations where it is highly desirable to perform work with low levels of vibration and noise, preventing the generation of noise and vibration becomes one of the most important goals; however, even in locations where the generation of some vibration and noise is not an impediment (e.g., locations somewhat distant from any dense residential area or business districts), it is nevertheless important to increase the efficiency of the excavation work and to reduce the number of construction workdays. Namely, while reducing the number of construction workdays reduces costs, it also reduces the number of days during which the area surrounding the site is exposed to vibration and noise.
Accordingly, an object of the present invention is to provide an excavating apparatus for underground excavation, a rotary excavator, and an underground excavating method wherein excavation work can be performed with low levels of vibration and noise.
Another object of the present invention is to provide an excavating apparatus for underground excavation, a rotary excavator, and an underground excavating method, wherein excavation work can be performed both with low levels of vibration and noise, and, by increasing the efficiency of the excavation work, over fewer construction workdays. This and other objects of the present invention will become obvious in the course of the explanation below.
SUMMARY OF THE INVENTION
The means devised by the present invention to achieve the abovementioned objects are as below.
Furthermore, while including in parenthesis reference numerals used in the drawings aid in understanding the explanation of the operation (discussed later), the constituent features are not limited to those symbols used in the drawings.
The present invention provides an excavating apparatus for underground excavation that includes: a plurality of bits, the outer diameters of which are smaller than that of an excavating apparatus main body, that advances to and retracts from an excavation side; piston case members, which correspond to the number of the bits and a plurality of which are housed inside the excavating apparatus main body, with built-in pistons that impart strike forces to the bits via the energy of a working fluid; a fluid storage part that stores the working fluid that is fed to each of the piston case members; working fluid distribution paths, a plurality of which are provided corresponding to the number of the piston case members, wherethrough the working fluid fed to each of the piston case members passes; and a rotary body that comprises a plurality of communication holes, which brings the fluid storage part and distribution ports into communication in order to feed the working fluid from the fluid storage part to the distribution ports of the working fluid distribution paths; wherein, the distribution ports are provided in the rotational direction of the rotary body such that the bits are impact driven staggered in time; and the communication holes are provided in the rotational direction with a layout different from that of the distribution ports in order to prevent each of the communication holes from communicating with each of the distribution ports simultaneously and with the same degree of openness.
The present invention may be configured such that the rotary body comprises a working fluid receiving blade for catching the working fluid and thereby rotating the rotary body.
The present invention may be configured such that the rotary body comprises working fluid supply holes that, separately from the communication holes, bring the fluid storage part and each of the distribution ports into communication; and the working fluid supply holes are set such that their inner diameters are smaller than those of the communication holes in order to supply part of the working fluid needed to impart the strike forces to the bits.
The present invention can include: a plurality of bits that are impact driven simultaneously separately and independently of the plurality of the bits that are impact driven staggered in time; wherein, the working fluid distribution paths of piston case members that correspond to the separately and independently driven bits are in a state of continuous communication with the fluid storage part without being controlled by the rotary body.
In addition, the present invention provides an excavating apparatus for underground excavation that has: a plurality of bits, the outer diameters of which are smaller than that of an excavating apparatus main body, that advances to and retracts from an excavation side; piston case members, which correspond to the number of the bits and a plurality of which are housed inside the excavating apparatus main body, with built-in pistons that impart strike forces to the bits via the energy of a working fluid; a fluid storage part that stores the working fluid that is fed to each of the piston case members; and working fluid distribution paths, a plurality of which are provided corresponding to the number of the piston case members, wherethrough the working fluid fed from the fluid storage part to each of the piston case members passes; wherein, at least one aspect selected from the group consisting of the distance of travel of the pistons ( 61 ) that move reciprocatively in order to impart strike forces to the bits, the sizes of the pistons, and the weights of the pistons, are set differently for each of the piston case members such that the bits, which are provided to the piston case members, are impact driven staggered in time.
Furthermore, the present invention provides an excavating apparatus for underground excavation that includes: a plurality of bits, the outer diameters of which are smaller than that of an excavating apparatus main body, that advances to and retracts from an excavation side; piston case members, which correspond to the number of the bits and a plurality of which are housed inside the excavating apparatus main body, with built-in pistons that impart strike forces to the bits via the energy of a working fluid; a fluid storage part that stores the working fluid that is fed to each of the piston case members; and working fluid distribution paths, a plurality of which are provided corresponding to the number of the piston case members, wherethrough the working fluid fed from the fluid storage part to each of the piston case members passes; wherein, the internal diameters of working fluid distribution paths, wherethrough the working fluid passes, are set differently for each of the piston case members such that the bits, which are provided to the piston case members, are impact driven staggered in time.
The present invention may be configured such that the fluid storage part is provided with a working fluid guide member that catches the working fluid supplied by the fluid storage part and guides such to the distribution ports.
The present invention may be configured such that the excavating apparatus main body is provided with vibration isolating and/or sound insulating materials such that they surround the piston case members.
The present invention is a rotary excavator that has: an excavating apparatus according to any one aspect of the abovementioned aspects; and a rotary drive apparatus that is capable of imparting rotary motion to the excavating apparatus.
Furthermore, the present invention is an underground excavating method wherein an excavating apparatus according to any one aspect of the abovementioned aspects is used, and includes the step of: performing underground excavation while imparting rotary motion to the excavating apparatus.
A gas, such as air (e.g., compressed air) or a liquid, such as water or oil, can be used as the “working fluid” recited in the present specification and the claims.
The number of distribution ports of the working fluid distribution paths provided in the rotational direction of the rotary body and the number of the communication holes of the rotary body may be the same or different (e.g., greater or lesser), as long as it is possible to prevent the communication holes and the distribution ports from communicating simultaneously and with the same degree of openness.
The cases listed below are examples of layouts of the communication holes and the distribution ports that can prevent the communication holes from communicating with the distribution ports simultaneously and with the same degree of openness.
If the number of the communication holes and the number of the distribution ports are the same, then either the communication holes or the distribution ports may be disposed equispaced, while the others are disposed not equispaced but rather with staggered spacing. In addition, both may be disposed not equispaced but rather with staggered spacing. Furthermore, if the number of the communication holes and the number of distribution ports are different, then there are cases wherein, depending on those numbers, both may be disposed equispaced. For example, in the case wherein the distribution ports are provided equispaced at five locations in the rotational direction of the rotary body and the communication holes are provided at six locations, then, even if the communication holes were disposed equispaced, it is still possible to prevent the communication holes from communicating with the distribution ports simultaneously and with the same degree of openness.
There are also cases wherein either the vibration isolating material or the sound insulating material is included in the “vibration isolating and/or sound insulating material” recited in the present specification and the claims, as well as cases wherein both the vibration isolating material and the sound insulating material are included (i.e., a material provided with both functions—vibration isolation and sound insulation—is included).
The excavating apparatus for underground excavation according to the present invention has a plurality of multiple bits whose outer diameters are smaller than that of the excavating apparatus main body, that advance to and retract from the excavation side, and that operate as follows.
(a) The rotation of the rotary body brings the fluid storage part and the distribution ports of the working fluid piston paths into communication via the plurality of communication holes, which are provided to the rotary body. Thereby, the working fluid is fed from the fluid storage part to each of the working fluid piston paths. As a result, the pistons, which are built into the piston case members, impart strike forces to the bits, which advance and retract to the excavation side of the excavating apparatus main body; thereby, excavation is performed.
Furthermore, in the present invention, the distribution ports are provided in the rotational direction of the rotary body such that the distribution ports can communicate with the communication holes, and, to prevent the communication holes from communicating with the distribution ports simultaneously and with the same degree of openness, the communication holes are provided in a layout different from that of the distribution ports. Thereby, it is possible to prevent the working fluid from being fed simultaneously and at the same flow rate from the fluid storage part to the piston case members. As a result, the bits are impact driven staggered in time. Accordingly, the impact on the soil foundation received for each strike of the bits is small.
(b) By providing the rotary body with working fluid receiving blades that catch the working fluid and thereby rotate the rotary body, the rotary body itself rotates without the addition of any other motive power. Consequently, it is possible to prevent problems such as complicating the structure or increasing the number of parts as in cases wherein other types of motive power are provided.
(c) The rotary body includes the working fluid supply holes, which bring the fluid storage part and the distribution ports into communication separately from the communication holes; consequently, attendant with the rotation of the rotary body, the working fluid is fed from the fluid storage part to the distribution ports via the working fluid supply holes, whose inner diameters are smaller than those of the communication holes, and the pistons move as far as the standby state prior to imparting the strike forces to the bits. Thereby, when the communication holes communicate with the distribution ports, the bits are impact driven promptly, and thus excavation is performed smoothly.
(d) A plurality of bits are provided, separately and independently of the plurality of bits that are impact driven staggered in time, that are impact driven simultaneously, and therefore the plurality of bits that are impact driven simultaneously can simultaneously impart a large impact force to the earth surface, yielding a high excavation working efficiency compared with the case wherein all of the bits are impact driven staggered in time.
(e) The working fluid is fed from the fluid storage part, which stores the working fluid, to the piston case members via the working fluid piston paths. Thereby, the pistons built into the piston case members impart strike forces to the bits for the purpose of excavation.
Furthermore, in the present invention, at least one aspect selected from the group including the distance of travel of the piston that moves reciprocatively to impart a strike force to the bit, the size of the piston, and the weight of the piston, is set differently for each of the piston case members, or the inner diameter of the working fluid paths through which the working fluid passes is set differently for each of the piston case members; therefore, by setting other conditions of the piston case members identically, the bits are impact driven staggered in time. Accordingly, the impact on the soil foundation received for each strike of the bits is small.
(f) By providing the working fluid guide member to the fluid storage part, the working fluid guide member catches the working fluid supplied by the fluid storage part and guides such to the distribution ports; thereby, the working fluid is fed uniformly, or uniformly to the degree possible, to each of the communication holes of the rotary body. In addition, the working fluid guide member catches the working fluid supplied by the fluid storage part and guides such to the working fluid paths; thereby, the working fluid is fed uniformly, or uniformly to the degree possible, to each of the working fluid paths. Thereby, it is possible to prevent nonuniformity in the working fluid that is fed to each of the piston case members and, as a result, to make the impact forces of each of the bits identical or identical to the degree possible; thereby, the excavation surface can be struck uniformly.
(g) In being provided to the excavating apparatus main body such that it surrounds the piston cases, the vibration isolating and/or sound insulating material mitigates the vibration and the sound generated when the pistons are driven.
(h) The rotary excavator according to the present invention performs excavation work while the rotary drive apparatus imparts rotary motion to the excavating apparatus. Through the imparting of this rotary motion, the excavation positions of the bits of the excavating apparatus move with respect to the excavation surface. Thereby, the bits strike the entire excavation surface without missing any spots.
The present invention has the abovementioned configuration and the effects described below.
(a) According to the excavating apparatus of the present invention, at least one aspect selected from the group consisting of the distance of travel of the piston that moves reciprocatively to impart a strike force to the bit, the size of the piston, and the weight of the piston, is set differently for each of the piston case members, or the inner diameter of the working fluid paths through which the working fluid passes is set differently for each of the piston case members; therefore, by setting other conditions of the piston case members identically, the bits are impact driven staggered in time.
Thereby, the impact on the soil foundation received for each strike of the bits is small compared with the conventional down-the-hole hammer, wherein the soil foundation is struck by moving up and down a hammer bit whose diameter is substantially the same as that of the hole to be excavated; consequently, excavation work can be performed with low levels of vibration and noise. Accordingly, the present invention is suitable for use in, for example, dense residential areas and urban business districts where it is desirable to perform work at lower levels of vibration and noise.
In addition, in contrast to the conventional excavating apparatus, which requires a comparatively large air compressor, the present invention needs only to drive comparatively small bits, and therefore the amount of the working fluid (e.g., air) required for a single bit to advance and retreat is small, which enables the supply apparatus that supplies the working fluid (e.g., the air compressor when the working fluid is air) to be made more compact. Thereby, only a small installation surface area is needed for the supply apparatus, and consequently the present invention is ideally suited to construction work performed at locations where space is limited, such as dense residential areas and urban business districts. In addition, reducing the size of the supply apparatus makes it possible to make the driving means, such as the engine that drives the supply apparatus, more compact; consequently, it is possible to reduce the levels of vibration and noise generated by the driving means.
(b) By providing the rotary body with working fluid receiving blades that catch the working fluid and thereby rotate the rotary body, the rotary body itself rotates without the addition of any other motive power; consequently, it is possible to prevent problems such as complicating the structure or increasing the number of parts as in cases wherein other types of motive power are provided.
(c) The rotary body includes working fluid supply holes, which bring the fluid storage part and the distribution ports into communication separately from the communication holes, and therefore the bits can be impact driven promptly; consequently, the excavation work can be performed smoothly.
(d) A plurality of bits are provided, separately and independently of the bits that are impact driven staggered in time, that are impact driven simultaneously, and therefore the plurality of bits that are impact driven simultaneously can simultaneously impart a large impact force to the earth surface, yielding a high excavation working efficiency. In addition, also provided are the plurality of bits that are impact driven staggered in time, which, compared with the case wherein all of the bits are impact driven staggered in time, makes it possible to reduce the number of construction work days needed to perform the excavation work.
(e) The working fluid guide member is provided to the fluid storage part, and therefore it is possible to prevent nonuniformity in the working fluid that is fed to each of the piston case members; consequently, the impact forces of every bit are made identical, or identical to the degree possible, and the excavation surface can be struck evenly.
(f) The excavating apparatus main body is provided with a vibration isolating and/or sound insulating material that surrounds the piston cases, which makes it possible to effectively prevent the leakage or external transmission of the vibration or the sound generated when the pistons are driven.
(g) According to the rotary excavator and the underground excavating method of the present invention, using the excavating apparatus, which has the effects mentioned above, while imparting rotary motion thereto makes it possible to perform excavation work at low levels of vibration and noise.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an explanatory oblique view of an excavating apparatus according to an embodiment, viewed from a tip side.
FIG. 2 is an explanatory longitudinal cross sectional view of the excavating apparatus shown in FIG. 1 .
FIG. 3 is an explanatory exploded oblique view of the excavating apparatus shown in FIG. 1 .
FIG. 4 includes explanatory side views that show the internal structure of a longitudinal cross section of the piston case member, which is housed in an excavating bit member.
FIG. 5 is an explanatory oblique view that shows a fluid guide member, which is disposed inside an air tank member of the excavating apparatus shown in FIG. 2 .
FIG. 6 is an explanatory oblique view that shows a rotary body, which is disposed inside the fluid guide member shown in FIG. 5 .
FIG. 7 is an explanatory plan view that shows the internal structure of the fluid guide member, including the rotary body, shown in FIG. 5 , with the cross section taken in the horizontal directions.
FIG. 8 includes explanatory partial schematic views that show rotating states of the rotary body shown in FIG. 7 over the course of time.
FIG. 9 is an explanatory side view that shows a rotary excavator that principally comprises the excavating apparatus and a rotary drive apparatus.
FIG. 10 is an explanatory partial enlarged view that shows another embodiment of the rotary body shown in FIG. 2 .
FIG. 11 is an explanatory longitudinal cross sectional view of the excavating apparatus according to another embodiment.
FIG. 12 is an explanatory plan view that shows the internal structure, including the rotary body, of an air guide member shown in FIG. 11 , wherein the cross section is taken along the horizontal directions.
FIG. 13 is an explanatory schematic view that shows variations of the excavating apparatus manufactured such that the number and positions of the bits vary.
FIG. 14 is an explanatory longitudinal cross sectional view of the excavating apparatus according to a further embodiment.
FIG. 15( a ) is the same explanatory longitudinal cross sectional view as the one shown in FIG. 4( a ), and FIG. 15( b ) is an explanatory longitudinal cross sectional view of another piston case member that is housed in the excavating bit member.
FIG. 16 is an explanatory oblique view that shows the fluid guide member, which is disposed inside the air tank member of the excavating apparatus shown in FIG. 14 .
FIG. 17 is an explanatory partial enlarged cross sectional view for explaining the excavating apparatus for underground excavation according to an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
The following text explains the present invention based on the various embodiments, but the present invention is not limited thereto.
FIG. 1 through FIG. 9 are views for explaining an embodiment of an excavating apparatus for underground excavation according to the present invention.
FIG. 1 is an explanatory oblique view of the excavating apparatus according to the embodiment, viewed from a tip side; FIG. 2 is an explanatory longitudinal cross sectional view of the excavating apparatus shown in FIG. 1 ; and FIG. 3 is an explanatory exploded oblique view of the excavating apparatus shown in FIG. 1 that shows an air tank member as well as an excavating bit member that has been removed from the air tank member. Furthermore, a base side (i.e., the upward side) of an air tank member 3 is not shown in FIG. 3 .
FIG. 4 is an explanatory side view that shows the internal structure of a longitudinal cross section of a piston case member, which is housed in the excavating bit member, wherein FIGS. 4 ( a )-( d ) show the states wherein the built-in piston moves up and down (i.e., undergoes advancing and retracting movement) over the course of time.
FIG. 5 is an explanatory oblique view that shows a fluid guide member, which is disposed inside the air tank member of the excavating apparatus shown in FIG. 2 . FIG. 6 is an explanatory oblique view that shows a rotary body, which is disposed inside the fluid guide member shown in FIG. 5 . FIG. 7 is an explanatory plan view that shows the internal structure, including the rotary body, of the fluid guide member shown in FIG. 5 , such that the cross section is taken in the horizontal directions; and FIGS. 8( a )-( d ) are explanatory partial schematic views that show the rotating states of the rotary body shown in FIG. 7 over the course of time, wherein FIG. 8( a ) corresponds to the state shown in FIG. 7 . Furthermore, air catching blades 45 and air supply holes 46 , which are shown in FIG. 7 , are not shown in FIG. 8 .
FIG. 9 is an explanatory side view that shows a rotary excavator, which principally includes the excavating apparatus and a rotary drive apparatus.
As shown in FIG. 9 , a rotary excavator 6 comprises an excavating apparatus 1 for underground excavation, which is shown in FIG. 1 , and a rotary drive apparatus 5 , which can provide rotary motion to the excavating apparatus 1 .
First, the excavating apparatus 1 will be explained, and then the rotary drive apparatus 5 will be explained.
Excavating Apparatus 1
As shown in FIG. 1 and FIG. 2 , the excavating apparatus 1 is formed such that its overall shape is substantially columnar. The excavating apparatus 1 comprises an excavating bit member 2 , which is an excavating apparatus main body positioned on the excavation side (i.e., the tip side), and an air tank member 3 , which is a working fluid storage member positioned on the base side.
The excavating bit member 2 comprises, at its tip, a plurality of bits 41 , 42 a , 42 b , 42 c , 42 d , 42 e (in the present embodiment, six). Each of the plurality of bits 41 , 42 a , . . . is smaller than the excavating bit member 2 . As shown in FIG. 9 (discussed below), the excavating apparatus 1 is suspended from a crane (not illustrated), and thereby is used in an erect state such that each of the bits 41 , 42 , . . . at the tip face downward.
In the present embodiment, as shown in FIG. 1 , the bits 41 , 42 a , . . . include: the center bit 41 , which is provided at one location on a shaft center part of the excavating bit member 2 , and the peripheral bits 42 a , 42 b , 42 c , 42 d , 42 e , which are provided at five locations equispaced along a circumference of which the center bit 41 serves as the center (i.e., equispaced around the center bit 41 ). As discussed below, whereas the head part of the center bit 41 is circular, the head part of each of the peripheral bits 42 a , . . . is substantially triangular.
The peripheral bits 42 a , . . . are not impact driven simultaneously; rather, they are configured such that each is impact driven staggered in time. In contrast, the center bit 41 is impact driven separately and independently of the strike operations of the other peripheral bits 42 a, . . . .
The air tank member 3 is detachably connected to the base side of the excavating bit member 2 by bolts 31 and nuts 32 , which are fastening tools (hidden in FIG. 1 ; refer to FIG. 2 ). As shown in FIG. 2 , the air tank member 3 has an air storage part 30 that can store air, which constitutes the working fluid that drives the bits 41 , 42 a , . . . , under high pressure.
The following text explains in detail and in order each constituent member of the excavating apparatus 1 .
(Excavating Bit Member 2 )
As shown in FIG. 3 , the excavating bit member 2 has, in order from above: piston case members 22 a , 22 b , 22 b , 22 b , 22 b , 22 b , each of which includes a connection body 21 and houses, for example, a driving means that includes a piston; a piston case mounting body 23 ; drive chucks 24 ; a chuck guide 25 ; and bits 41 , 42 a, . . . .
Each of the piston case members 22 a , 22 b , . . . has a cylindrical piston case main body 220 that is made of a metal. The connection body 21 is screwed to a base end part (in FIG. 3 , an upper part) of each of the piston case main bodies 220 . The bits 41 , 42 a , . . . are connected to tip parts (in FIG. 3 , lower parts) of the corresponding piston case main bodies 220 via the drive chucks 24 and the chuck guide 25 . The piston case members 22 a , 22 b are provided in the same number as the bits 41 , 42 a , . . . (in the present embodiment, a plurality at a total of six locations).
Furthermore, for the sake of convenience in the explanation below, the piston case member 22 a corresponding to the center bit 41 is sometimes called the “center piston case member 22 a ,” and the piston case members 22 b corresponding to the peripheral bits 42 a , . . . are sometimes called the “peripheral piston case members 22 b.”
We now refer to FIG. 4 which shows the singular center piston case member 22 a that is housed in the excavating bit member, but the other peripheral piston case members 22 b have substantially the same structure, differing only in the shape of the bit 41 , and all pistons 61 perform reciprocating motion in the same manner.
As shown in FIG. 4 , a driving means, which includes the piston 61 that operates the bit 41 , is built into (housed in) the piston case main body 220 . Namely, in addition to the piston 61 , the piston case main body 220 is provided with a cylinder 62 , a check valve 63 , an air distributor 64 (i.e., a rigid valve), a valve spring 65 , a foot valve 66 , a make-up ring, an O-ring, a piston retainer ring, and a bit retainer ring. This driving means is the same as or substantially the same as the drive mechanism of the well known down-the-hole hammer (e.g., as recited in Japanese Unexamined Patent Application Publication No. S61-92288), and a detailed explanation thereof is therefore omitted.
The drive mechanism will now be explained in simple terms, referencing FIGS. 4( a )-( d ).
First, in the state wherein the excavating apparatus 1 is suspended prior to the excavation work as shown in FIG. 9 , the bit 41 at the tip is in the state wherein it protrudes from the tip of the piston case member 22 a owing to its own weight, as shown in FIG. 4( a ). In this state, a tip side circumferential surface part of the piston 61 contacts an inner circumferential surface of the piston case main body 220 , and the air that is introduced from an air hose 351 does not circulate (i.e., is not fed to) the tip part side of the piston 61 . Thereby, the piston 61 does not rise (i.e., does not move to the base side of the piston case main body 220 ), and the bit 41 is in a drive stopped state.
Furthermore, as shown in FIG. 4( b ), when the excavating apparatus 1 in the suspended state is lowered until the bit 41 makes contact with an excavation surface L, which is the earth surface (or the ground surface), the self weight of the excavating apparatus 1 causes the bit 41 to move into the interior of the piston case main body 220 . Thereby, air circulates to the lower part side of the piston 61 because of a gap that is created between the tip side circumferential surface part of the piston 61 and the inner circumferential surface of the piston case main body 220 and pushes the piston 61 up at high speed, as shown in FIG. 4( c ) as well as FIG. 4( d ).
Subsequently, when the piston 61 rises to a required position, the tip side circumferential surface part of the piston 61 once again contacts the inner circumferential surface of the piston case main body 220 , and the air no longer circulates to the tip part side of the piston 61 . Thereby, the air circulates to an upper part side of the piston 61 , and the piston 61 that was pushed up is now pushed down at high speed and strikes the base side of the bit 41 at the tip, as shown in FIG. 4( a ). Thereby, the air that enters from the foot valve 66 passes through the interior of the bit 41 and is exhausted from the tip part side thereof; in addition, the bit 41 protrudes from the tip and is impact driven. The impact forces that accompany the up and down repetitive reciprocating motion of the piston 61 cause the excavation side of the bit 41 (and likewise, of the bits 42 a , . . . corresponding to the piston case members 22 b ) to advance and retract, thereby digging into the earth.
Each of the bits 41 , 42 a , . . . vibrationally strikes (i.e., moves up and down or advances and retracts) at high speed and thereby excavates the soil foundation. For example, each bit is impact driven 1,200-1,300 times per minute, and collectively the bits are impact driven approximately 7,200-7,800 times per minute. Furthermore, even if the same excavating apparatus 1 is used, the number of strikes per unit of time varies with the hardness of the stratum to be excavated. In the case of a hard stratum, after the soil foundation is struck, the bits 41 , 42 a , . . . return quickly and the subsequent up and down movement of the piston 61 becomes intense; consequently, the number of strikes of each of the bits 41 , 42 a , . . . increases.
As shown in FIG. 2 and FIG. 3 , the connection body 21 positioned at the base end part of each of the piston case main bodies 220 has a hole 211 (not visible in FIG. 3 ), which constitutes the path of the working fluid; furthermore, the base end side of the connection body 21 is formed in the shape of a protrusion in a cross section. That protruding portion constitutes an insertion part 222 , which is mounted to the air tank member 3 by inserting it thereinto. Thus, the air that is fed from the air tank member 3 via the insertion part 222 of the connection body 21 drives the driving means inside each of the piston case members 22 a , 22 b.
Each of the piston case members 22 a , 22 b , . . . (in the present embodiment, a total of six) is detachably attached to the piston case mounting body 23 (refer to FIG. 3 ), which is a mounting body with a substantially columnar shape. The piston case mounting body 23 principally comprises: a tubular main body 231 (refer to FIG. 2 ); a cover body 233 (hereinbelow, called a “tip part cover body 233 ”), which is fastened to the tip part side opening of the tubular main body 231 ; and a cover body 234 (hereinbelow, called a “base cover body 234 ”), which is fastened to the base side opening of the tubular main body 231 .
Furthermore, piston case casings 232 (refer to FIG. 2 ), which are long and thin casings with a cylindrical shape, are housed inside the piston case mounting body 23 . Each of the piston case casings 232 is attached such that the corresponding piston case main body 220 is inserted therein. The piston case casings 232 number the same as the piston case main bodies 220 and are provided such that their axial directions are oriented in the longitudinal directions of the piston case mounting body 23 .
The tip part cover body 233 has a required thickness and is provided with through holes 235 , which are holes through which the piston case members 22 are inserted. Likewise, the base cover body 234 has a required thickness and is provided with through holes 236 (refer to FIG. 2 ), which are holes through which the piston case members 22 a , 22 b are inserted. In the present embodiment, the through holes 235 are provided at a total of six locations, namely, at one location in the center part and at five locations equispaced along the circumference whose center is the center part; likewise, the through holes 236 are provided at a total of six locations, namely, at one location in the center part and at five locations equispaced along the circumference whose center is the center part.
As shown in FIG. 2 , each of the abovementioned piston case casings 232 is fastened such that it is interposed above and below by the two cover bodies 233 , 234 and is housed inside the tubular main body 231 . The tip side holes (symbol omitted) of the piston case casings 232 communicate with the through holes 235 of the tip part cover body 233 . The base end side holes (symbol omitted) of the piston case casings 232 communicate with the through holes 236 of the base cover body 234 .
Furthermore, an air gap portion formed between each of the piston case main bodies 220 , 220 inside the piston case mounting body 23 (i.e., the tubular main body 231 ) is filled with sand 230 (refer to FIG. 2 ), which serves as a vibration isolating and/or sound insulating material.
In addition, the tip part of each of the piston case main bodies 220 partly protrudes from the tip part cover body 233 . The base end sides of the substantially tubular drive chucks 24 shown in FIG. 3 are attached such that they are somewhat tightly pushed into holes (symbol omitted) of these protruding portions. The base sides of the bits 41 , 42 a , . . . are retractably accommodated in tip side holes 241 of the drive chucks 24 via the chuck guide 25 .
The chuck guide 25 is substantially circular in a plan view, has a required thickness, and is fastened to the tip (i.e., the tip part cover body 233 ) of the piston case mounting body 23 . The chuck guide 25 is fastened using bolts 251 and nuts 252 (shown on the left side of the piston case mounting body 23 in FIG. 3 ), both of which are fastening tools; furthermore, the nuts 252 are attached from the piston case mounting body 23 side.
The tip part side of the chuck guide 25 is provided with a recessed part 253 , which is disposed at the center and is circular in the paper plane view, and a required number of recessed parts 254 , which are V-shaped grooves in the paper plain view and are disposed radially such that they surround the recessed part 253 . The center bit 41 , which comprises a head part 411 that is circular in the paper plane view, is disposed inside the recessed part 253 . The peripheral bits 42 a - 42 e , each of which includes a head part 421 that is substantially triangular in the paper plane view, are disposed in the recessed parts 254 . Numerous button chips 412 , which are made of cemented carbide, are provided to the head parts 411 , 421 of the bits 41 , 42 a, . . . .
The chuck guide 25 is provided with mounting holes 255 , which are mounts that have holes and number the same as the bits 41 , 42 a , . . . . The mounting holes 255 are positioned inside the recessed part 253 and the recessed parts 254 mentioned above. The tip parts of the drive chucks 24 mate with the base sides of the mounting holes 255 . Each of the drive chucks 24 has a detent 242 , which has a hexagonal nut shape; furthermore, hexagonally-shaped recessed parts 256 (refer to FIG. 2 ), whereto the detents 242 are mated, are formed in the mounting holes 255 of the chuck guide 25 .
The base side of each of the bits 41 , 42 a , . . . is formed as a splined shaft; furthermore, each of these base sides mates with the tip part of the corresponding mounting hole 255 and thereby is mounted inside the corresponding drive chuck 24 , the inner circumferential wall of which is grooved (not illustrated) for engaging therewith. The base side of each of the bits 41 , 42 a , . . . is mounted with the abovementioned bit retainer ring and O-ring such that it does not detach from the corresponding drive chuck 24 .
In addition, as shown in FIG. 1 , a required number of flat bars 26 , which are projections, are provided to the outer circumference of the piston case mounting body 23 such that they are oriented in the axial directions thereof. In the present embodiment, multiple flat bars 26 are provided at required intervals in the circumferential directions (at a total of six locations). Furthermore, the air jetted from the tip part side of the excavating bit member 2 (i.e., the chuck guide 25 ) delivers to the ground surface the crushed bedrock, earth and sand (i.e., slime), and the like generated inside the excavated hole during soil foundation excavation work through gaps between the flat bars 26 , 26 and the excavated hole.
Air Tank Member 3
A coupling joint 34 , which is for introducing air, is provided such that it protrudes from the base end part (i.e., the upper end part in FIG. 2 ) of the air tank member 3 . The air introduced via the coupling joint 34 is stored inside the air storage part 30 , which is disposed inside the air tank member 3 . A symbol 340 indicates a blow-out hole of the coupling joint 34 .
As shown in FIG. 3 , a coupling body 33 , which is for the purpose of coupling with the base end part of the excavating bit member 2 (i.e., the insertion part 222 side of each of the piston case members 22 a ), is provided to the tip part side of the air tank member 3 . Furthermore, as shown in FIG. 2 , the air storage part 30 is provided internally closer to the base side (in FIG. 2 , the upward side) than the coupling body 33 . The air storage part 30 is compartmentalized on the coupling body 33 side by a compartment body 300 , which comprises a plate shaped body that is circular in a plan view.
As shown in FIG. 3 , a required number of coupling holes 331 is provided to the tip part of the coupling body 33 . Furthermore, as shown in FIG. 2 , one end part (in FIG. 2 , the lower end part) of the air hose 351 and each of air hoses 352 is connected to the insertion part 222 of the corresponding piston case member 22 a , . . . , which is inserted into the corresponding coupling hole 331 .
The other end part (in FIG. 2 , the upper end part) of each of the air hoses 351 , 352 is connected to a corresponding compartment hole 3 a , 3 b , 3 c , 3 d , 3 e , 3 f (shown by broken lines in FIG. 7 ); note that the compartment holes 3 a , 3 b , 3 c , 3 d , 3 e , 3 f are distribution holes for working fluid that are formed in the compartment body 300 . Each of the compartment holes 3 a , . . . and each of the air hoses 351 , 352 constitute working fluid piston paths for feeding the working fluid to the piston case members 22 a , 22 b.
Furthermore, in FIG. 2 , not all of the air hoses are shown; however, the air hoses are provided corresponding to the total number of the piston case members 22 a , 22 b (i.e., the same number as the piston case members 22 a , 22 b ; in the present embodiment, six). In addition, in the present embodiment, the coupling body 33 that houses the air hoses 351 , 352 is, on the whole, a hollow substantially tubular body, but the coupling body 33 can also be formed as a solid shape.
In the present embodiment, each of the compartment holes 3 a , . . . shown by the broken lines in FIG. 7 is a circular hole. The compartment holes 3 a , . . . are provided such that they correspond to the number of piston case members 22 a , 22 b , . . . . Namely, as shown by the broken lines in FIG. 7 , the compartment hole 3 f (hereinbelow, sometimes called the “center compartment hole 3 f ”) is provided in one location at the center part of the compartment body 300 ; furthermore, the compartment holes 3 a , 3 b , 3 c , 3 d , 3 e (hereinbelow sometimes called the “peripheral compartment holes 3 a ”) are provided in five locations equispaced along a circumference whose center is the center compartment hole 3 f.
The air hose 351 (refer to FIG. 2 ; hereinbelow, called the “center air hose 351 ”), which leads out from the center piston case member 22 a that corresponds to the center bit 41 shown in FIG. 1 , is connected to the center compartment hole 3 f . The remaining peripheral compartment holes 3 a , . . . that surround the center compartment hole 3 f are connected to the air hoses 352 (refer to FIG. 2 ; hereinbelow, called the “peripheral air hoses 352 ”), which lead out from the piston case members 22 b that correspond to the peripheral bits 42 a , . . . shown in FIG. 1 . The peripheral air hoses 352 all have the same inner diameter and length.
Furthermore, a rotary body 40 (refer also to FIG. 6 ), which rotates by catching the air inside the air storage part 30 , is provided on the air storage part 30 side in FIG. 2 . The rotary body 40 is provided such that it contacts the compartment body 300 . The rotary body 40 will be discussed later in detail.
Air Guide Member 8
The rotary body 40 shown in FIG. 6 is disposed inside the air guide member 8 , which is a working fluid guide member that is shaped like a cup (in one embodiment like a sake cup), as shown in FIG. 2 and FIG. 5 . The air guide member 8 includes: an air guide receptacle 81 , which is a working fluid guide receptacle that has a semispherical shape (i.e., the shape of half a ball) and that catches the air from the blow-out hole 340 of the coupling joint 34 ; and a rotary body housing 82 that has a conical wall part, which is a substantially conical body, that supports the air guide receptacle 81 . In the present embodiment, a base end part 823 (in FIG. 2 , the lower end part) of the rotary body housing 82 is fixed to the compartment body 300 in the vicinity of the circumferential edge part of the compartment body 300 , but the base end part 823 can also be directly or indirectly fixed to an inner wall surface 304 of the air storage part 30 .
A required number of intake parts 821 , 822 , wherethrough the air is taken into the rotary body housing 82 , is provided to the rotary body housing 82 shown in FIG. 5 . In the present embodiment, the intake parts are the intake holes 821 , which are provided on the tip part side (in FIG. 5 , the upper side) of the rotary body housing 82 , and the intake pipes 822 , which are provided on the base side (in FIG. 5 , the lower side) of the rotary body housing 82 .
The intake holes 821 (refer also to FIG. 2 ) are provided at three locations equispaced along the circumferential surface directions of the rotary body housing 82 . Each of the intake holes 821 is provided such that it is inclined in the diagonally downward direction in FIG. 2 and such that it discharges toward the rotary body 40 within. As shown in FIG. 7 , the intake pipes 822 are provided slightly inclined along the rotational direction of the rotary body 40 such that the air therefrom strikes the semicircular shaped air catching blades 45 (discussed below; refer also to FIG. 6 ), a required number of which are provided to the rotary body 40 , and thereby causes the rotary body 40 to rotate smoothly. Furthermore, the intake pipes 822 are provided such that they are inclined slightly in the diagonally downward direction toward the rotary body 40 in FIG. 2 .
Based on such a configuration, the air supplied from the blow-out hole 340 of the coupling joint 34 , shown in the upper part of FIG. 2 , strikes the receptacle 81 of the air guide member 8 , then rebounds along the recessed part surface of the receptacle 81 , returns to the rotary body housing 82 side along an arcuate path, emerges via the intake holes 821 and the intake pipes 822 , and is fed to the rotary body 40 side.
Rotary Body 40
As shown in FIG. 6 and FIG. 7 , the rotary body 40 includes a rotary plate 43 , which is circular in a plan view, and a tubular rotational shaft 4 f , which is a shaft part that axially and rotatably supports the rotary plate 43 . As shown in FIG. 2 , the rotational shaft 4 f is rotatably inserted into the center compartment hole 3 f at the center of the compartment body 300 (refer also to FIG. 7 ) and has a structure such that it cannot slip out of the center compartment hole 3 f.
As described above, the center air hose 351 is connected to the center compartment hole 3 f (refer to FIG. 2 ). Thereby, the air storage part 30 and the center air hose 351 are in continuous communication via the rotational shaft 4 f . Accordingly, the air inside the air storage part 30 is fed continuously to the center air hose 351 and drives the piston 61 inside the center piston case member 22 a ; thereby, the center bit 41 is impact driven separately from and independently of each of the peripheral bits 42 a , . . . . A symbol 301 indicates a rolling body, such as a ball bearing.
FIG. 10 is an explanatory partial enlarged view that shows another embodiment of the rotary body shown in FIG. 2 .
The rotary body 40 shown in FIG. 6 is integral with the rotational shaft 4 f and the rotary plate 43 and rotates together therewith. In contrast, as shown in FIG. 10 , a configuration can also be adopted wherein a rotary plate 43 a rotates such that a shaft part 44 a , which is fixed to the compartment body 300 , serves as the axis. In this case, the shaft part 44 a can be configured such that it is long, an other end part 441 thereof (the lower end part in FIG. 10 ) can be coupled to the center piston case member 22 a by inserting it into the hole 211 of the center piston case member 22 a , and the tip part of a rotational shaft 4 g can be formed with a diameter larger than that of the compartment hole 3 f , as in the head of a bolt. Symbols 302 indicate rolling bodies, such as ball bearings.
In addition, as shown in FIG. 7 , to control the degrees of openness of the air storage part 30 (which is positioned closer to the paper surface than the rotary plate 43 is in FIG. 7 ) and of the peripheral compartment holes 3 a , 3 b , 3 c , 3 d , 3 e (shown by broken lines), the rotary plate 43 has a size such that it can cover the portion of the compartment body 300 wherein the peripheral compartment holes 3 a , . . . are provided and is provided such that it contacts the compartment body 300 . The rotary plate 43 has rotational holes 4 a , 4 b , 4 c , 4 d , 4 e , which bring the air storage part 30 into communication with each of the peripheral compartment holes 3 a , . . . . Each of the rotational holes 4 a , . . . constitutes a communication path wherethrough air is distributed.
As shown in FIG. 6 , a required number of the rotational holes 4 a , 4 b , 4 c , 4 d , 4 e is disposed at required intervals along a circumference (i.e., along the rotational direction of the rotary body 40 ) such that the rotational shaft 4 f serves as the center. In the present embodiment, the rotational holes 4 a , . . . are provided at five locations corresponding to the number of the peripheral piston case members 22 b , . . . that drive the peripheral bits 42 a , . . . . Each of the rotational holes 4 a , . . . is a circular hole with an inner diameter that is the same or substantially the same as that of each of the peripheral compartment holes 3 a, . . . .
Furthermore, the rotational holes 4 a , . . . or the peripheral compartment holes 3 a , . . . , or both, can be formed as holes that have an oblong (i.e., an elliptical) shape in a plan view and can also be formed as holes of some other shape, for example, square or rectangular. Furthermore, each of the rotational holes 4 a can be formed with an inner diameter that is larger than that of the peripheral compartment holes 3 a , and vice versa.
The rotational holes 4 a , . . . are not equispaced but rather are disposed at varying intervals (i.e., with staggered spacing) along the rotational direction of the rotary body 40 such that the rotation of the rotary body 40 gradually increases the degree of openness, in sequence of the rotational holes 4 a , . . . in the rotational direction, of the peripheral compartment holes 3 a, . . . .
Namely, whereas the peripheral compartment holes 3 a , . . . , which are shown by broken lines in FIG. 7 , are provided at five locations equispaced along the same circumference, the rotational holes 4 a , . . . , which are shown by solid lines, are not equispaced at five locations along this circumference but rather are provided at varying intervals, as discussed below. Accordingly, for the sake of explanatory convenience, the rotational hole 4 a , which is not in communication with the peripheral compartment hole 3 a in the lower right of FIG. 7 , is referred to as the first rotational hole 4 a , and the corresponding peripheral compartment hole 3 a is referred to as the first compartment hole 3 a.
In addition, in clockwise order in FIG. 7 (i.e., in the order of the direction opposite the rotational direction) starting from the first rotational hole 4 a , let us refer to the subsequent rotational holes as the second rotational hole 4 b , the third rotational hole 4 c , the fourth rotational hole 4 d , and the fifth rotational hole 4 e . Similarly, in clockwise order in FIG. 7 (i.e., in the order of the direction opposite the rotational direction) starting from the first compartment hole 3 a shown by the broken line, let us refer to the subsequent compartment holes as the second compartment hole 3 b , the third compartment hole 3 c , the fourth compartment hole 3 d , and the fifth compartment hole 3 e.
In so doing, in the state shown in FIG. 7 , the second rotational hole 4 b communicates with the second compartment hole 3 b such that approximately ⅓ of its inner diameter overlaps the second compartment hole 3 b ; the third rotational hole 4 c communicates with the third compartment hole 3 c such that approximately ½ of its inner diameter overlaps the third compartment hole 3 c ; the fourth rotational hole 4 d communicates with the fourth compartment hole 3 d such that approximately ⅔ of its inner diameter overlaps the fourth compartment hole 3 d ; and the fifth rotational hole 4 e communicates completely with the fifth compartment hole 3 e such that it entirely overlaps the fifth compartment hole 3 e . Furthermore, the rotation of the rotary body 40 causes each of the rotational holes 4 a , . . . to communicate with each of the peripheral compartment holes 3 a , . . . and the air is fed through the peripheral air hoses 352 to the peripheral piston case members 22 b , where it drives the peripheral bits 42 a , . . . shown in FIG. 1 . The detailed operation of the rotary body 40 will be discussed later.
As shown in FIG. 6 and FIG. 7 , the semicircular shaped air catching blades 45 are provided (at a total of five locations) in the vicinity of substantially the middle position between each adjacent pair of rotational holes 4 a , 4 b , . . . . The air catching blades 45 are disposed along the circumferential edge part of the rotary plate 43 . The air catching blades 45 are fixed to the rotary plate 43 of the rotary body 40 via rod shaped support parts 451 (refer to FIG. 6 ). The air catching blades 45 are attached such that their recessed part surfaces face opposite the rotational direction and such that the rotary body 40 rotates in the left-handed rotational direction (i.e., counterclockwise) in FIG. 6 . Furthermore, the present invention is not limited to the number of air catching blades 45 illustrated.
Furthermore, as illustrated in FIG. 7 , a required number of the air supply holes 46 , which are working fluid supply holes that pass through the rotary plate 43 and whose inner diameters are smaller than those of the rotational holes 4 a , is provided between adjacent pairs of air catching blades 45 and rotational holes 4 a , . . . (in the present embodiment, at one location per pair with a total of 10 locations over the entire rotary plate 43 ). The air supply holes 46 are provided along a circumference such that the rotational shaft 4 g serves as the center and such that they communicate with the peripheral compartment holes 3 a , 3 b , 3 c , 3 d , 3 e . The rotation of the rotary body 40 brings each of the air supply holes 46 into communication with one of the peripheral compartment holes 3 a , . . . , and thereby the air from the air storage part 30 is fed a little bit at a time to each of the peripheral piston case members 22 b and drives the piston 61 therein as far as the standby state prior to a strike. The operation will be discussed later.
Outer Circumferential Portion of the Air Tank Member 3
As shown in FIG. 2 , the air tank member 3 on the base side (i.e., the upper part side in FIG. 2 ) of the coupling body 33 bounds the coupling body 33 and is formed such that it narrows slightly toward its base side. The outer diameter of a small caliber portion 36 , which is formed with a diameter slightly smaller than that of the coupling body 33 , matches the inner diameter of a tubular drive bushing 51 , which is provided to the rotary drive apparatus 5 (discussed below; refer to FIG. 9 ). Furthermore, as shown in FIG. 9 , the excavating apparatus 1 , in the erect state, is dropped down such that the drive bushing 51 mates with the base end part of the excavating apparatus 1 , whereupon the drive bushing 51 stops the excavating apparatus 1 at the portion at which the diameter of the air tank member 3 is large (in the vicinity of the coupling body 33 ), and the excavating apparatus 1 does not drop downward any further. The details of this operation are discussed later.
Furthermore, as shown in FIG. 1 , a required number of flat bars 361 , which are projections, are provided to the outer circumference of the air tank member 3 such that they are oriented in the axial directions thereof. In the present embodiment, a plurality of flat bars 361 is provided (at a total of six locations). Furthermore, when excavation work is performed, these flat bars 361 engage with mating grooves provided to an inner wall part of the drive bushing 51 of the rotary drive apparatus 5 (refer to FIG. 9 ), which comprises a rotary table that is discussed below, and transmit the rotary drive force (i.e., the rotary motion) of the drive bushing 51 to the excavating apparatus 1 .
Rotary Drive Apparatus 5
Moreover, as described above, the rotary drive apparatus 5 shown in FIG. 9 imparts rotary motion to the excavating apparatus 1 . The rotary drive apparatus 5 comprises a rotary drive apparatus main body 50 and outriggers 52 , which support the rotary drive apparatus main body 50 . As described above, the rotary drive apparatus main body 50 comprises a rotary table (not shown in FIG. 9 because it is hidden), whereto the excavating apparatus 1 can be mounted via the drive bushing 51 and that can impart rotary motion to the excavating apparatus 1 .
Operation
The operation of the rotary excavator 6 , which comprises the excavating apparatus 1 , will now be explained. Furthermore, the present embodiment explains the operation of the rotary excavator 6 taking as an example a case wherein a pile hole is excavated in the soil foundation.
First, as shown in FIG. 9 , the rotary drive apparatus 5 , which is a constituent element of the rotary excavator 6 , is mounted on temporary footholds 600 , which are erected using, for example, H-beams. Moreover, a required number (i.e., a necessary number) of kelly rods 7 , in accordance with the length of the hole to be excavated in the soil foundation, are connected to the base end part of the excavating apparatus 1 . In the present embodiment, one kelly rod 7 may be connected, or two or more (i.e., a plurality) may be connected.
The kelly rod 7 has a built-in air supply pipe. The kelly rod 7 and the excavating apparatus 1 are fastened together by fastening tools (not illustrated), which comprise pins, bolts, nuts, and the like. The excavating apparatus 1 , to which the kelly rod 7 is connected, is supported by the crane (not shown in the drawings) such that it is suspended therefrom. In FIG. 9 , a symbol 73 indicates a wire that is connected to the crane.
Furthermore, the drive bushing 51 is set on the rotary table (hidden in FIG. 5 and therefore not shown) of the rotary drive apparatus 5 . Furthermore, while the excavating apparatus 1 is suspended from and supported by the crane, the flat bars 361 of the air tank 30 member 3 of the excavating apparatus 1 are engaged with mating grooves (hidden in the drawings and therefore not shown), which are grooves in the inner wall of the drive bushing 51 . Furthermore, excavation is started while the excavating apparatus 1 is suspended from the crane.
During excavation, the rotary drive force transmitted from the rotary table to the drive bushing 51 is further transmitted to the air tank member 3 , and thereby the excavating apparatus 1 rotates. A support shaft 71 , which is for suspending the kelly rod 7 from the crane, is provided to the upper end of the kelly rod 7 . A supply pipe 72 , which supplies air to the excavating apparatus 1 , is connected to the support shaft 71 . In addition, an air swivel (not illustrated) is provided to the support shaft 71 .
The air fed from the supply pipe 72 is fed to the excavating apparatus 1 via the air supply pipe of the kelly rod 7 . The air fed to the excavating apparatus 1 is discharged from the blow-out hole 340 of the coupling joint 34 , which is shown in FIG. 2 , and stored in the air storage part 30 .
The air supplied from the blow-out hole 340 strikes the receptacle 81 of the air guide member 8 , then rebounds along the recessed part surface of the receptacle 81 , returns to the rotary body housing 82 side along an arcuate path, and is fed to the rotary body 40 side.
Furthermore, while the air catching blades 45 catch the air, the rotary body 40 rotates in the left-handed rotational direction (i.e., counterclockwise) starting from the state shown in FIG. 8( a ) and proceeding, in order, through the states shown in FIGS. 8( b ), ( c ), and ( d ). Furthermore, FIGS. 8( a )-( d ) show the rotating states of the rotary body 40 over the course of time; however, for the sake of explanatory convenience, the time intervals between the drawings are not all the same.
The air rotates the rotary body 40 , additionally passes through the air hoses 351 , 352 via both the tubular rotational shaft 4 f ( 4 g ) and the rotational holes 4 a - 4 e of the rotary body 40 shown in FIG. 2 ( FIG. 10 ), is fed to the corresponding piston case members 22 a , 22 b , and impact drives the center bit 41 and the peripheral bits 42 a, . . . .
Among the bits, the center bit 41 is not controlled by the amount of air flow from the rotary body 40 , and therefore the air that is continuously fed from the rotational shaft 4 f ( 4 g ) to the center piston case member 22 a impact drives the center bit 41 independently of the strike operation of the other peripheral bits 42 a.
In contrast, the rotation of the rotary body 40 controls the degrees of openness of the air storage part 30 and the peripheral compartment holes 3 a , and thereby the peripheral bits 42 a , . . . are impact driven as described below.
Namely, in the state shown in FIG. 8( b ), the fifth rotational hole 4 e that was in communication with the fifth compartment hole 3 e in FIG. 8( a ) moves and transitions to the noncommunicative state; the other rotational holes 4 a , 4 b , 4 c , 4 d transition to states of noncommunication with the other peripheral compartment holes 3 a , 3 b , 3 c , 3 d.
In addition, in the state shown in FIG. 8( c ), which is achieved by further rotation, the first rotational hole 4 a that was in the noncommunicative state as shown in FIG. 8( b ) now communicates with the fifth compartment hole 3 e such that approximately ⅔ of its inner diameter overlaps the fifth compartment hole 3 e , the second rotational hole 4 b communicates with the first compartment hole 3 a such that approximately ⅓ of its inner diameter overlaps the first compartment hole 3 a , and the third rotational hole 4 c is still in the noncommunicative state. The communication states of the fourth rotational hole 4 d and the fifth rotational hole 4 e as illustrated in FIG. 8( c ) are both in the noncommunicative state.
Furthermore, in the state shown in FIG. 8( d ), the first rotational hole 4 a that was in approximately ⅔ communication in the state shown in FIG. 8( c ) is now in complete communication with the fifth compartment hole 3 e , the second rotational hole 4 b that was in approximately ⅓ communication now communicates with the first compartment hole 3 a such that approximately ½ of its inner diameter overlaps the first compartment hole 3 a , and the third rotational hole 4 c that was in the noncommunicative state now communicates with the second compartment hole 3 b such that approximately ⅓ of its inner diameter overlaps the second compartment hole 3 b . The communication states of the fourth rotational hole 4 d and the fifth rotational hole 4 e are in minor communication with the third compartment hole 3 c and in the noncommunicative state with the fourth compartment hole 3 d , respectively.
As described above, the rotation of the rotary body 40 gradually increases—in the rotational direction—the degrees of openness of each of the first rotational holes 4 a , . . . to the corresponding compartment holes 3 a , . . . ; furthermore, after each of the first rotational holes 4 a , . . . has been brought, in order, into communication, each returns once again to the noncommunicative state shown in FIG. 8( b ), and the cycle is then performed repetitively.
Thus, by bringing, in order, each of the rotational holes 4 a , . . . into communication in the rotational direction of the rotary body 40 , the air is not introduced from the air storage part 30 to the peripheral piston case members 22 b simultaneously, but rather is introduced sequentially and staggered in time. Thereby, the peripheral bits 42 a , . . . (refer to FIG. 1 ) corresponding to the peripheral piston case members 22 b strike, in turn, in the order of the peripheral bits 42 a , 42 b , 42 c , 42 d , 42 e in the circumferential directions. Accordingly, the impact forces produced by the strikes of the bits 41 , 42 a , . . . are imparted to the excavation surface substantially evenly, without missing a spot.
In addition, as described above, the rotation of the rotary body 40 brings the air supply holes 46 , the inner diameters of which are smaller than that of the rotational hole 4 a , into communication with the peripheral compartment holes 3 a , . . . , and thereby the air from the air storage part 30 is fed a little bit at a time to each of the peripheral piston case members 22 b . Thereby, the working fluid is fed until the piston 61 inside each of the peripheral piston case members 22 b reaches the standby state prior to strike (i.e., the state wherein the piston 61 has moved upward or the state wherein the air is fed to the peripheral piston case members 22 b to some degree even though the corresponding piston 61 does not rise). As a result, when each of the rotational holes 4 a coincides with the corresponding peripheral compartment hole 3 a , the corresponding piston 61 promptly falls and the bit 41 strikes. Namely, the time shift between the coincidence of one of the rotational holes 4 a with one of the peripheral compartment holes 3 a and the striking of the bit 41 is eliminated or shortened.
Thus, by performing the impact drive while the bits 42 a , . . . are operated staggered in time, the excavation work can be performed at lower noise and vibration levels than those of the conventional down-the-hole hammer, wherein the earth surface is struck by moving up and down one hammer bit with a diameter substantially the same as the hole to be excavated. Accordingly, the present invention is suited to use in, for example, dense residential areas and urban business districts.
Furthermore, the rotary motion imparted to the excavating apparatus 1 by the rotary drive apparatus 5 moves, with respect to the excavation surface, the excavation position of each of the peripheral bits 42 a , . . . of the excavating apparatus 1 . Thereby, the bits 41 , 42 strike the entire excavation surface without missing any spots. In addition, rotating the excavating apparatus 1 smoothly delivers the crushed bedrock, earth and sand (i.e., slime), and the like produced during excavation to the ground surface.
In addition, as shown in FIG. 2 , the driving means, such as the pistons 61 that operate the bits 41 , 42 a , . . . , are housed inside the piston case main bodies 220 , are furthermore covered by the tubular piston case casings 232 , and are furthermore housed inside the tubular main body 231 that is filled with the sand 230 , which is a vibration isolating and/or sound insulating material. Thereby, it is possible to prevent the sound and vibration generated during the drive of the driving means from leaking externally or being transmitted, and therefore to reduce the sound and vibration levels.
In addition, in the present embodiment, the rotary drive apparatus 5 comprises the outriggers 52 , which not only improve stability during excavation work, but also dampen vibration transmitted from the rotary drive apparatus main body 50 to the grounding surface to a greater extent than the case wherein excavation is performed with the rotary drive apparatus main body 50 mounted directly on the grounding surface. Thereby, the present invention effectively reduces vibration and noise levels.
Furthermore, as described above, the conventional art necessitates driving a hammer bit with a large diameter substantially the same as that of the hole to be excavated; consequently, driving the hammer bit up and down inevitably consumes a large amount of air, and therefore a comparatively large air compressor is required.
In contrast, in the present embodiment, each of the small-diameter bits 41 , 42 a , . . . is driven, in turn, into the hole to be excavated; accordingly, because a small amount of air is consumed in moving a single bit up and down, the air compressor used can be made more compact. Accordingly, the air compressor needs only a small amount of installation surface area, and the present invention is suited to construction work in locations where space is limited, such as dense residential areas and urban business districts. In addition, making the air compressor more compact makes it possible to reduce the size of the prime mover that drives the air compressor, which in turn makes it possible to reduce the levels of vibration and noise generated by the prime mover.
Furthermore, in the present embodiment, the excavating bit member 2 that is provided with the bits 41 , 42 a , . . . at a total of six locations is used, but the present invention is not particularly limited to that number. In the present embodiment, the diameter of the excavating bit member 2 is, for example, 450-700 mm.
Unlike the present embodiment, if the excavating bit member 2 were configured with bits at, for example, five locations (i.e., in one location at the shaft center part and in four locations therearound), then the diameter of the excavating bit member 2 could be, for example, less than 450 mm. Furthermore, if the excavating bit member 2 were configured with bits at, for example, six to seven locations (i.e., in one location at the shaft center part and in five locations or six locations therearound), then the diameter of the excavating bit member 2 could be, for example, 700 mm or greater.
Furthermore, a screw shaft that comprises an air supply pipe can be used instead of the kelly rod 7 . If a screw shaft were used, then the crushed bedrock, earth and sand (i.e., slime), and the like generated during excavation could be delivered (i.e., removed) to the ground surface more smoothly. In addition, helical blades for earth removal can also be provided to a circumferential surface part of the air tank member 3 .
In addition, the present embodiment explained the case wherein excavation work is performed using the rotary drive apparatus 5 that comprises the rotary table, but the means for imparting rotary motion to the excavating apparatus 1 is not limited to the rotary table; for example, it is also possible to employ a well known rotary driving means, such as a three point pile driver or a leader.
FIG. 11 and FIG. 12 are views for explaining another embodiment of the excavating apparatus for underground excavation according to the present invention.
FIG. 11 is an explanatory longitudinal cross sectional view of the excavating apparatus according to this embodiment, and FIG. 12 is an explanatory plan view that shows the internal structure of the air guide member, including the rotary body, shown in FIG. 11 , with the cross section taken in the horizontal directions; furthermore, FIG. 11 is a view that corresponds to FIG. 7 mentioned above.
Furthermore, in the present embodiment, the same symbols are assigned at the same or equivalent locations as those in the above embodiment. In addition, the following text omits explanations of locations explained in the above embodiment and principally explains the points of difference.
In the previous embodiment described above (refer to FIG. 2 and FIG. 7 ), the rotary body 40 controls the degrees of openness of the five peripheral compartment holes 3 a , 3 b , 3 c , 3 d , 3 e . In contrast, with an excavating apparatus 1 a according to the present embodiment, a rotary body 40 a shown in FIG. 12 controls the degrees of openness of three compartment holes 5 a , 5 b , 5 c (hereinbelow, called the “inward compartment holes 5 a , 5 b , 5 c ”). Furthermore, three compartment holes 5 d , 5 e , 5 f (hereinbelow, called the “outward compartment holes 5 d , 5 e , 5 f ”) are disposed on the outer side of the rotary body 40 a.
The excavating apparatus 1 a according to the present embodiment will now be explained in greater detail.
Unlike in the above embodiment (refer to FIG. 2 ), a rotational shaft 4 h of the rotary body 40 a shown in FIG. 11 is not formed tubularly and air hoses are not connected thereto. Rather, the rotational shaft 4 h is provided such that it is rotatably inserted into and will not slip off of a bearing hole 303 , which is formed in the center of a compartment body 300 a . The abovementioned inward compartment holes 5 a , 5 b , 5 c (indicated by the broken lines) are disposed at three locations equispaced along the circumference of the compartment body 300 a (refer to FIG. 12 ), such that the bearing hole 303 serves as the center.
Among the compartment holes, the singular inward compartment hole 5 a (positioned on the right side in FIG. 12 ) is connected to a peripheral air hose 353 , which leads out from the peripheral piston case member 22 b (refer to FIG. 11 ) that corresponds to the peripheral bit 42 a shown in FIG. 1 . In addition, of the remaining compartment holes, the inward compartment hole 5 b (positioned to the lower right of the compartment hole 5 a in FIG. 12 ) is connected to a peripheral air hose 354 (partly not shown; refer to FIG. 11 ), which leads out from the peripheral piston case member 22 b that corresponds to the peripheral bit 42 c shown in FIG. 1 . Furthermore, the other remaining inward compartment hole, that is, the inward compartment hole 5 c (positioned to the upper left of the compartment hole 5 a in FIG. 12 ) is connected to a peripheral air hose 355 (refer to FIG. 11 ), which leads out from the peripheral piston case member 22 b that corresponds to the peripheral bit 42 d shown in FIG. 1 . Furthermore, the inner diameters and the lengths of the air hoses 353 , 354 , 355 to which these inward compartment holes 5 a , 5 b , 5 c are connected are all the same.
The rotary plate 43 a has rotational holes 6 a , 6 b , 6 c , which bring the air storage part 30 and the inward compartment holes 5 a , 5 b , 5 c into communication. Each of the inward rotational holes 6 a , . . . comprises a communication path wherethrough air is distributed. A required number of the rotational holes 6 a , 6 b , 6 c is disposed at required intervals along the circumference of the rotary plate 43 a (i.e., in the rotational direction of the rotary body 40 a ) such that the center of rotation of the rotary plate 43 a serves as the center. In the present embodiment, the rotational holes 6 a , 6 b , 6 c are provided at a total of three locations, corresponding in number to the abovementioned inward compartment holes 5 a , 5 b , 5 c . In addition, in the present embodiment, each of the rotational holes 6 a , 6 b , 6 c is a circular hole whose inner diameter is substantially the same as that of the inward compartment holes 5 a , 5 b , 5 c.
As described above, the inward compartment holes 5 a , 5 b , 5 c (indicated by the broken lines) are provided equispaced. In contrast, the rotational holes 6 a , . . . are not equispaced but rather are disposed at varying intervals (i.e., with staggered spacing) along the rotational direction of the rotary body 40 a such that the rotation of the rotary body 40 a gradually increases the degree of openness, in sequence of the rotational holes 6 a , . . . in the rotational direction, of the compartment holes 5 a , 5 b , 5 c.
For the sake of explanatory convenience, the rotational hole 6 a , the full circle of which is in complete communication with the inward compartment hole 5 a (positioned on the right side in FIG. 12 ), shall be called the first rotational hole 6 a . Furthermore, in clockwise order (i.e., in the direction opposite the rotational direction) in FIG. 12 and starting from the first rotational hole 6 a , the other rotational holes shall be called the second rotational hole 6 b and the third rotational hole 6 c . In addition, similarly, in the clockwise order (i.e., in the direction opposite the rotational direction) in FIG. 12 and starting from the inward compartment hole 5 a on the right side, the other compartment holes shall be called the second inward compartment hole 5 b and the third inward compartment hole 5 c.
In the present embodiment, in the state shown in FIG. 12 , the second rotational hole 6 b communicates with the second inward compartment hole 5 b such that approximately ⅓ of its inner diameter overlaps the second inward compartment hole 5 b ; furthermore, the third rotational hole 6 c communicates with the third inward compartment hole 5 c such that approximately ½ of its inner diameter overlaps the third inward compartment hole 5 c . The communicating states between the rotational holes 6 a , . . . and the inward compartment holes 5 a , . . . created by the rotation of the rotary body 40 a will be discussed later, along with the operation thereof.
As shown in FIG. 12 , a required number of the air catching blades 45 (at two locations between adjacent pairs of rotational holes 6 a , . . . , with a total of six locations) are provided with required spacings between adjacent pairs of rotational holes 6 a , . . . . Furthermore, air supply holes 46 , whose inner diameters are smaller than those of the rotational holes 6 a , are provided at required positions between pairs of rotational holes 6 a and air catching blades 45 such that the air supply holes 46 avoid the rotational holes 6 a and the air catching blades 45 . The operation of the air catching blades 45 and the air supply holes 46 is the same as that in the previous embodiment, and therefore the explanation thereof is omitted.
As shown in FIG. 11 , the base end part 823 (i.e., the lower end part in FIG. 11 ) of the rotary body housing 82 is fixed slightly inside the circumferential edge part of the compartment body 300 a . Furthermore, a required number of the outward compartment holes 5 d , 5 e , 5 f (in the present embodiment, at three locations equispaced to create the vertices of an equilateral triangle), which are distribution holes wherethrough the working fluid is distributed, are provided at required intervals in the portion of the compartment body 300 a (refer also to FIG. 12 ) positioned between the base end part 823 and the inner wall surface 304 of the air storage part 30 .
Among the compartment holes, the singular outward compartment hole 5 d (positioned on the right side in FIG. 12 ) is connected to a center air hose 356 , which leads out from the center piston case member 22 a (refer to FIG. 11 ) that corresponds to the center bit 41 shown in FIG. 1 . In addition, of the remaining compartment holes, the outward compartment hole 5 e (positioned to the lower right in FIG. 12 ) is connected to a peripheral air hose (partly not shown), which leads out from the peripheral piston case member 22 b that corresponds to the peripheral bit 42 b shown in FIG. 1 . Furthermore, the other remaining outward compartment hole, that is, the outward compartment hole 5 f (positioned to the upper left in FIG. 12 ), is connected to a peripheral air hose (not shown), which leads out from the peripheral piston case member 22 b that corresponds to the peripheral bit 42 e shown in FIG. 1 . Furthermore, the diameters and the lengths of the air hoses to which these outward compartment holes 5 d , 5 e , 5 f are connected are all the same.
Operation
The excavating apparatus 1 a according to the present embodiment operates as described below. Furthermore, explanations of portions of the operation that are in principle the same as those described in the above embodiment will be omitted.
As in the above embodiment, the air supplied from the blow-out hole 340 of the coupling joint 34 shown in FIG. 11 strikes the air guide member 8 , is fed to the tip part side of the air storage part 30 , and is partly fed to the rotary body 40 a inside the rotary body housing 82 .
The air fed to the tip part side of the air storage part 30 is then fed to the outward compartment holes 5 d , 5 e , 5 f positioned on the outer side of the rotary body housing 82 in FIG. 12 . Furthermore, air is continuously fed from the outward compartment holes 5 d , 5 e , 5 f to the corresponding piston case members 22 a , 22 b , 22 b without being controlled by the distribution of the air by the rotary body 40 a , and thereby the center bit 41 , the peripheral bit 42 b , and the peripheral bit 42 e shown in FIG. 1 are impact driven simultaneously.
Moreover, the air fed to the interior of the rotary body housing 82 rotates the rotary body 40 a shown in FIG. 12 in the left-handed rotation direction (i.e., counterclockwise). Furthermore, the rotation of the rotary body 40 a controls the degrees of openness between the air storage part 30 and the inward compartment holes 5 a , 5 b , 5 c . Namely, by making the rotational holes 6 a , 6 b , 6 c , which are indicated by the solid lines in FIG. 12 , coincide with the inward compartment holes 5 a , 5 b , 5 c , which are indicated by the broken lines, the air storage part 30 and the inward compartment holes 5 a , 5 b , 5 c communicate, and thereby the peripheral bits 42 a , . . . shown in FIG. 1 are impact driven in order and staggered in time.
In detail, as in the rotary body 40 explained in the above embodiment, the inward compartment holes 5 a , 5 b , 5 c are not equispaced but rather are disposed at varying intervals (i.e., with staggered spacing). Furthermore, the rotation of the rotary body 40 a gradually increases the degrees of openness—in the rotational direction—between the first rotational holes 6 a , . . . and the inward compartment holes 5 a , 5 b , 5 c , and thereby the air is not introduced from the air storage part 30 to the peripheral piston case members 22 b simultaneously but rather is introduced sequentially and staggered in time. Thereby, the peripheral bits 42 a , 42 c , 42 d shown in FIG. 1 strike, in that order, staggered in time.
To reiterate the drive states of the bits 41 , 42 a , . . . explained above referencing FIG. 1 , the three bits, that is, the center bit 41 and the peripheral bits 42 b , 42 e , are simultaneously impact driven, and the remaining three bits, that is, the peripheral bits 42 a , 42 c , 42 d , are impact driven, in that order, staggered in time.
Thus, unlike the previous embodiment (which is configured such that all of the peripheral bits 42 b , . . . are impact driven in order and staggered in time), the present embodiment (i.e., the second embodiment) comprises both the peripheral bits 42 a , 42 c , 42 d , which are impact driven in order and staggered in time, as well as the center bit 41 and the peripheral bits 42 b , 42 e , which are impact driven simultaneously.
Accordingly, in the present embodiment, the center bit 41 and the peripheral bits 42 b , 42 e , which are impact driven simultaneously, impart simultaneously a large impact force to the earth surface, yielding a high excavation working efficiency. In other words, although the previous embodiment is superior to the present embodiment with regard to reduction of the vibration and noise levels, the present embodiment is superior with regard to excavation working efficiency.
Accordingly, in locations where the generation of some vibration and noise is not a problem (e.g., locations somewhat distant from any dense residential area or urban business district), the use of the excavating apparatus 1 a of the present embodiment is the superior choice for increasing excavation working efficiency and decreasing the number of construction work days.
In addition, even if excavation work were performed at the same site as construction work, the effect of vibration and noise on the area surrounding the site would diminish as the depth of the hole in the earth increased. Accordingly, as a first step, the excavating apparatus 1 (refer to FIG. 2 ) of the previous embodiment is used to dig into the ground surface up to a required depth; next, as a second step, the excavation apparatus 1 is replaced with the excavating apparatus 1 a (refer to FIG. 11 ) of the present embodiment, which continues the excavation work; as a result, excavation working efficiency can be improved and the number of construction work days can be reduced while minimizing the impact of vibration and noise on the areas surrounding the site.
Furthermore, with respect to the reduction of vibration and noise levels, the present embodiment is certainly superior to the conventional down-the-hole hammer, wherein a single hammer bit with a diameter substantially the same as that of the hole to be excavated is impact driven.
In addition, in the present embodiment, three of the plurality of bits 41 , 42 a , . . . shown in FIG. 1 , namely, the center bit 41 and the peripheral bits 42 b , 42 e , can be impact driven simultaneously, but the present invention is not particularly limited to the number and positions of the simultaneously driven bits.
Furthermore, FIG. 13 shows variations in the excavation apparatuses manufactured with different numbers of bits at different positions and schematically shows the states of the excavating apparatuses, viewed from the bit tips. In FIG. 13 , bits 47 are indicated by the small circles and the excavating bit member 2 is indicated by the large circles.
The present invention is not particularly limited with respect to the total number and the positions of the bits; for example, each of the variations shown in FIG. 13 , namely, excavating apparatuses 1 d - 1 l , is conceivable. Namely, as shown in FIG. 13 , bits can be provided at, for example, four to ten locations; furthermore, bits can be provided at three locations or at eleven or more locations. In addition, the center bits 47 may be omitted, and it is also possible to provide a bit at one location in the center, as well as to provide bits at two, three, or more locations at the center.
FIG. 14 through FIG. 16 are views for explaining the embodiment of the excavating apparatus for underground excavation according to the present invention. FIG. 14 is an explanatory longitudinal cross sectional view of the excavating apparatus according to this embodiment; FIG. 15 includes FIG. 15( a ), which is the same explanatory longitudinal cross sectional view as that shown in FIG. 4( a ), and FIG. 15( b ), which is an explanatory longitudinal cross sectional view of another piston case member housed in the excavating bit member; and FIG. 16 is an explanatory oblique view that shows the fluid guide member, which is disposed inside the air tank member of the excavating apparatus shown in FIG. 14 . An excavating apparatus 1 b will now be explained. Furthermore, the same symbols are assigned at the same or equivalent locations as those in the previous embodiments. In addition, the following text omits explanations of locations explained in the previous embodiments and principally explains the points of difference.
Excavating Apparatus 1 b
The excavating apparatus 1 b is configured such that the bits 41 , . . . according to the excavating bit member 2 are impact driven (i.e., they move up and down or advance and retract) not simultaneously but rather staggered in time. The following text explains in detail the constituent members of the excavating apparatus 1 b and the points of difference from the other embodiments.
Excavating Bit Member 2
Refer now to FIG. 15 . In addition to the center piston case member 22 a mentioned above, the excavating bit member 2 is provided with the five peripheral piston case members 22 b , . . . . Furthermore, with regard to the center piston case member 22 a and the other five peripheral piston case members 22 b , . . . , the lengths of piston case main bodies 220 a , 220 b differ and the sizes of the pistons 61 , 61 b housed in the piston case main bodies 220 a , 220 b also differ.
Namely, the length in the longitudinal directions of the piston case main body 220 b of the peripheral piston case member 22 b shown in, for example, FIG. 15( b ) is shorter than that of the piston case main body 220 a of the center piston case member 22 a shown in FIG. 15( a ). Namely, a distance L 2 from the air distributor 64 to the bit 42 a shown in FIG. 15( b ) is shorter than a distance L 1 from the air distributor 64 to the bit 41 shown in FIG. 15( a ).
Furthermore, corresponding to the length of the piston case main body 220 b , the length in the longitudinal directions of the piston 61 b of the peripheral piston case member 22 b shown in FIG. 15( b ) is shorter than that of the piston 61 of the center piston case member 22 a shown in FIG. 15( a ). In other words, the piston 61 b , which is shorter than the piston 61 , also weighs less than the piston 61 .
Adopting such a configuration of the piston case members 22 a , 22 b means that even if the same amounts of air were fed from the air storage part 30 shown in FIG. 14 to each of the air hoses 351 , 352 , the piston 61 b of the peripheral piston case member 22 b shown in FIG. 15( b ) will be able to be driven with a smaller amount of air. Accordingly, the number of strikes per unit of time of the peripheral piston case member 22 b shown in FIG. 15( b ) is greater than that of the center piston case member 22 a shown in FIG. 15( a ).
For example, assuming that the center piston case member 22 a shown in FIG. 15( a ) impact drives the bit 41 approximately 1,200 times per minute, then the peripheral piston case member 22 b shown in FIG. 15( b ) can be set to the state wherein the bit 42 a is impact driven approximately 200 strikes per minute more, namely, 1,400 times per minute.
Furthermore, although not shown, the lengths of each of the remaining four peripheral piston case members 22 b , . . . corresponding to the other bits 42 a , 42 c , 42 d , 42 e differ, and the sizes of each of the pistons housed therein also differ. Thereby, the number of strikes per minute also differs among them (e.g., the bit 42 a can be set to 1,600 times per minute, the bit 42 c can be set to 1,800 times per minute, the bit 42 d can be set to 2,000 times per minute, and the bit 42 e can be set to 2,200 times per minute). As a result, the six bits 41 , . . . shown in FIG. 1 move up and down not simultaneously but rather staggered in time, and therefore the soil foundation can be excavated.
Furthermore, even if the same bit is used, the number of strikes per unit of time of the bits 41 , . . . varies with the hardness of the stratum to be excavated. In the case of a hard stratum, after the soil foundation is struck, the bits 41 , . . . return quickly and the subsequent up and down movement of the piston 61 becomes intense; consequently, the number of strikes of each of the bits 41 , . . . increases.
As shown in FIG. 14 , the connection body 21 positioned at the base end part of each of the piston case main bodies 220 a , 220 b has a hole 211 (not visible in FIG. 3 ), which constitutes the path of the working fluid; furthermore, the base end side of the connection body 21 is formed in the shape of a protrusion in a cross section. That protruding portion constitutes the insertion part 222 , which is mounted to the air tank member 3 by inserting it thereinto. Thus, the air that is fed from the air tank member 3 via the insertion part 222 of the connection body 21 drives the driving means inside each of the piston case members 22 a , 22 b.
The piston case casings 232 (refer to FIG. 14 ), which are long and thin casings with a cylindrical shape, are housed inside the piston case mounting body 23 . Each of the piston case casings 232 is attached such that the corresponding piston case main body 220 a , 220 b is inserted therein. The piston case casings 232 number the same as the piston case main bodies 220 a , 220 b and are provided such that their axial directions are oriented in the longitudinal directions of the piston case mounting body 23 .
An air gap portion formed between each of the piston case main bodies 220 a , 220 b inside the piston case mounting body 23 (i.e., the tubular main body 231 ) is filled with sand 230 (refer to FIG. 2 ), which serves as a vibration isolating and/or sound insulating material.
The tip part of each of the piston case main bodies 220 a , 220 b partly protrudes from the tip part cover body 233 . The base end sides of the substantially tubular drive chucks 24 shown in FIG. 3 are attached such that they are somewhat tightly pushed into holes (symbol omitted) of these protruding portions. The base sides of the bits 41 , . . . are retractably accommodated in tip side holes 241 of the drive chucks 24 via the chuck guide 25 .
The other end parts (i.e., the upper end parts in FIG. 14 ) of the air hoses 351 , 352 are connected to the compartment holes 3 a , 3 d , 3 f , which are distribution holes formed in the abovementioned compartment body 300 wherethrough the working fluid is distributed (in FIG. 14 , three compartment holes are shown, and the symbols for the remaining three compartment holes not shown are omitted). The compartment holes 3 a , . . . and the air hoses 351 , 352 constitute working fluid distribution parts for feeding the working fluid to the piston case members 22 a , 22 b.
In the present embodiment, each of the compartment holes 3 a is a circular hole. The compartment holes 3 a are provided such that they correspond to the number of piston case members 22 a , 22 b . Namely, the compartment hole 3 f (hereinbelow, sometimes called the “center compartment hole 3 f ”) is provided in one location at the center part of the compartment body 300 ; furthermore, the compartment holes 3 a , 3 d , 3 f , . . . (hereinbelow sometimes called the “peripheral compartment holes 3 a ”) are provided in five locations equispaced along a circumference whose center is the center compartment hole 3 f.
The air hose 351 (refer to FIG. 14 ; hereinbelow, called the “center air hose 351 ”), which leads out from the center piston case member 22 a that corresponds to the center bit 41 shown in FIG. 1 , is connected to the center compartment hole 3 f . The remaining peripheral compartment holes 3 a , . . . that surround the center compartment hole 3 f are connected to the air hoses 352 (refer to FIG. 14 ; hereinbelow, called the “peripheral air hoses 352 ”), which lead out from the piston case members 22 b that correspond to the peripheral bits 42 a , . . . shown in FIG. 1 . The center air hose 351 and the peripheral air hoses 352 all have the same inner diameter and length.
Air Guide Member 8 a
An air guide member 8 a , which is a working fluid guide member for guiding the air supplied from the coupling joint 34 to each of the compartment holes 3 a , . . . of the compartment body 300 , is provided inside the air storage part 30 . As shown in FIG. 16 , the air guide member 8 a is formed in the shape of a cup (i.e., a saké cup).
The air guide member 8 a includes: the air guide receptacle 81 , which has a semispherical shape (i.e., the shape of half a ball) and that catches the air from the blow-out hole 340 of the coupling joint 34 ; and a rotary body housing 82 a that comprises a conical wall part, which is a substantially conical body, that supports the air guide receptacle 81 . In the present embodiment, a base end part 823 (in FIG. 14 , the lower end part) of the rotary body housing 82 a is fixed to the compartment body 300 in the vicinity of the circumferential edge part of the compartment body 300 , but the base end part 823 can also be directly or indirectly fixed to an inner wall surface 304 of the air storage part 30 .
A required number of the intake holes 821 , each of which is an intake part that takes air into the interior of the rotary body housing 82 a , is provided to the rotary body housing 82 a shown in FIG. 16 . The required number of the intake holes 821 (in the present embodiment, a plurality) is provided equispaced (at eight locations) along the circumferential surface directions of the rotary body housing 82 a near the tip part side (in FIG. 16 , the upper side) and near the base side (in FIG. 16 , the lower side) of the rotary body housing 82 a . Each of the intake holes 821 is provided inclined in the diagonally downward direction in FIG. 14 such that it discharges toward the compartment holes 3 a , . . . of the compartment body 300 .
Based on such a configuration, the air supplied from the blow-out hole 340 of the coupling joint 34 , shown in the upper part of FIG. 14 , strikes the air guide receptacle 81 of the air guide member 8 a , then rebounds along the recessed part surface of the air guide receptacle 81 , returns to the rotary body housing 82 a side along an arcuate path, emerges via the intake holes 821 , and is fed to each of the compartment holes 3 a , . . . of each of the compartment body 300 .
Operation
The operation of the rotary excavator 6 , which includes the excavating apparatus 1 b , will now be explained. Furthermore, explanations of portions of the operation that are in principle the same as those described in the above embodiments will be omitted.
In addition, both the method of setting up the rotary excavator 6 and the procedure leading up to the start of work are the same as those in the above embodiments, and therefore the explanations thereof are omitted; the following text explains the operation after the point in time at which the air is fed from the supply pipe 72 to the excavating apparatus 1 b.
The air fed from the supply pipe 72 is fed to the excavating apparatus 1 b via the air supply pipe of the kelly rod 7 . The air fed to the excavating apparatus 1 b is discharged from the blow-out hole 340 of the coupling joint 34 , which is shown in FIG. 2 , and stored in the air storage part 30 .
The air supplied from the blow-out hole 340 strikes the air guide receptacle 81 of the air guide member 8 , then rebounds along the recessed part surface of the air guide receptacle 81 , returns to the rotary body housing 82 a side along an arcuate path, emerges via the intake holes 821 , and is fed to each of the compartment holes 3 a , . . . of each of the compartment body 300 .
Furthermore, air passes through the air hoses 351 , 352 that correspond to the compartment holes 3 a , . . . , is introduced to the piston case members 22 a , . . . , drives the pistons 61 , 61 b , . . . , and moves the bits 41 , 42 a , . . . at the tip up and down.
Furthermore, as mentioned above, the lengths of the piston case main bodies 220 a , 220 b of the piston case members 22 a differ and the sizes of the pistons 61 b , . . . housed in the piston case main bodies 220 a , 220 b also differ; consequently, the number of strikes per minute differs. Thereby, the bits 41 , 42 a move up and down staggered in time and do not simultaneously and continually strike the soil foundation. Furthermore, because the diameters of the bits 41 , 42 are smaller than that of the hole to be excavated, the impact on the earth surface received with each strike of each of the bits 41 , 42 is small.
In addition, as shown in FIG. 14 , the driving means, such as the pistons 61 that operate the bits 41 , . . . , are housed inside the piston case main bodies 220 a , 220 b , are furthermore covered by the tubular piston case casings 232 , and are furthermore housed inside the tubular main body 231 that is filled with the sand 230 , which is a vibration isolating and/or sound insulating material. Thereby, it is possible to prevent the sound and vibration generated during the drive of the driving means from leaking externally or being transmitted, and therefore to reduce the sound and vibration levels.
FIG. 17 is an explanatory partial enlarged cross sectional view for explaining the excavating apparatus for underground excavation according to the present embodiment and, to facilitate understanding of the thicknesses of the air hoses, shows an enlargement of a portion that includes the air hoses.
Furthermore, explanations of portions of the operation described in the above embodiments will be omitted. In addition, the following text omits explanations of locations explained in the above embodiment and principally explains the points of difference.
In the previous embodiment, (refer to FIG. 14 ), the lengths of the piston case main bodies 220 a , 220 b in the piston case members 22 a , 22 b differ and the sizes of the pistons 61 b , . . . housed in the piston case main bodies 220 a , 220 b also differ; thereby, the bits 41 , . . . are impact driven not simultaneously but rather staggered in time.
In contrast, in an excavating apparatus 1 c (refer to FIG. 17 ) according to the present embodiment, while the lengths of the piston case main bodies 220 a , 220 b , the sizes of the pistons housed in the piston case main bodies 220 a , 220 b , and other conditions remain the same, and all of the same constituent elements are used, there are notable differences regarding whether the piston case members 22 a , 22 b comprise the center bit 41 and whether they comprise the peripheral bits 42 a.
Accordingly, in the present embodiment, the diameters of the air hoses 351 , 352 a , 352 b , 352 c , . . . , which are connected to the piston case members 22 a , 22 b , vary such that the bits 41 , . . . are impact driven not simultaneously but rather staggered in time. Thereby, the arrival times of the air introduced from the air storage part 30 to each of the piston case members 22 a , 22 b are staggered, and, as a result, the times at which the bits 41 , . . . are impact driven are also staggered.
Furthermore, the arrival times of the air introduced to the piston case members 22 a , 22 b may be staggered by varying both the diameters and the lengths of the air hoses 351 , 352 a , 352 b , 352 c, . . . .
Other operational aspects and effects are the same as or substantially the same as those in the above embodiment, and consequently the explanations thereof are omitted.
Furthermore, the terms and expressions used in the present specification are merely for the sake of the explanation made herein, and the present invention is not limited thereto; for example, terms and expressions equivalent to those mentioned above are not excluded from the present invention. In addition, the present invention is not limited to the illustrated embodiments, and it is understood that variations and modifications may be effected without departing from the scope of the invention's technical concept.
Furthermore, while including in parenthesis in the claims reference numerals used in the drawings aids in understanding the content of the claims, the scope of the claims is not limited to those symbols used in the drawings.
(a) According to the excavating apparatus of the present invention, at least one aspect selected from the group consisting of the distance of travel of the piston that moves reciprocatively to impart a strike force to the bit, the size of the piston, and the weight of the piston, is set differently for each of the piston case members, or the inner diameter of the working fluid paths through which the working fluid passes is set differently for each of the piston case members; therefore, by setting other conditions of the piston case members identically, the bits are impact driven staggered in time.
Thereby, the impact on the soil foundation received for each strike of the bits is small compared with the conventional down-the-hole hammer, wherein the soil foundation is struck by moving up and down a hammer bit whose diameter is substantially the same as that of the hole to be excavated; consequently, excavation work can be performed with low levels of vibration and noise. Accordingly, the present invention is suitable for use in, for example, dense residential areas and urban business districts where it is desirable to perform work at lower levels of vibration and noise.
In addition, in contrast to the conventional excavating apparatus, which requires a comparatively large air compressor, the present invention needs only to drive comparatively small bits, and therefore the amount of the working fluid (e.g., air) required for a single bit to advance and retreat is small, which enables the supply apparatus that supplies the working fluid (e.g., the air compressor when the working fluid is air) to be made more compact. Thereby, only a small installation surface area is needed for the supply apparatus, and consequently the present invention is ideally suited to construction work performed at locations where space is limited, such as dense residential areas and urban business districts. In addition, reducing the size of the supply apparatus makes it possible to make the driving means, such as the engine that drives the supply apparatus, more compact; consequently, it is possible to reduce the levels of vibration and noise generated by the driving means.
(b) By providing the rotary body with working fluid receiving blades that catch the working fluid and thereby rotate the rotary body, the rotary body itself rotates without the addition of any other motive power; consequently, it is possible to prevent problems such as complicating the structure or increasing the number of parts as in cases wherein other types of motive power are provided.
(c) The rotary body includes working fluid supply holes, which bring the fluid storage part and the distribution ports into communication separately from the communication holes, and therefore the bits can be impact driven promptly; consequently, the excavation work can be performed smoothly.
(d) A plurality of bits are provided, separately and independently of the bits that are impact driven staggered in time, that are impact driven simultaneously, and therefore the plurality of bits that are impact driven simultaneously can simultaneously impart a large impact force to the earth surface, yielding a high excavation working efficiency. In addition, also provided are the plurality of bits that are impact driven staggered in time, which, compared with the case wherein all of the bits are impact driven staggered in time, makes it possible to reduce the number of construction work days needed to perform the excavation work.
(e) The working fluid guide member is provided to the fluid storage part, and therefore it is possible to prevent nonuniformity in the working fluid that is fed to each of the piston case members; consequently, the impact forces of every bit are made identical, or identical to the degree possible, and the excavation surface can be struck evenly.
(f) The excavating apparatus main body is provided with a vibration isolating and/or sound insulating material that surrounds the piston cases, which makes it possible to effectively prevent the leakage or external transmission of the vibration or the sound generated when the pistons are driven.
(g) According to the rotary excavator and the underground excavating method of the present invention, using the excavating apparatus, which has the effects mentioned above, while imparting rotary motion thereto makes it possible to perform excavation work at low levels of vibration and noise. | An excavator for underground excavating arranged to perform excavating work with low vibration and low noise. A rotary excavator and an underground excavating method are also provided. The excavator ( 1 ) for underground excavating comprises a plurality of bits ( 42 a , . . . ) having the outside diameter smaller than that of the excavator body ( 2 ) and advancing/retracting to/from the excavating side, piston case members ( 22 b , . . . ) incorporating pistons ( 61 ) for applying a hitting force to respective bits ( 42 a , . . . ) by the energy of working fluid, a section ( 30 ) for storing the working fluid being fed to respective piston case members ( 22 b , . . . ), working fluid circulation passages ( 352 ) for allowing the working fluid being fed to respective piston case members ( 22 b , . . . ) to pass, and a body of rotation ( 40 ) provided with a plurality of holes ( 4 a , . . . ) for allowing the fluid storage section ( 30 ) to communicate with the circulation openings ( 3 a , . . . ) of each working fluid circulation passage ( 352 ) in order to feed the working fluid from the fluid storage section ( 30 ) to the circulation openings ( 3 a , . . . ) of the respective working fluid circulation passages ( 352 ). | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a carrier suitable for a development by a magnetic brush.
Development of an electrostatic latent image can be effected by attracting a minus or plus toner frictionally charged on a plus or minus electostatic latent image formed on a photosensitive member respectively. In order to charge the toner a plus or minus charged carrier is used. If the carrier can be optionally varied in its polarity of charge, one kind of neutral toner can be used as a toner chargeable to both plus and minus polarities.
Hitherto, as methods of changing the polarity of charge on a binder type carrier there are disclosed in Japanese Patent Publication (KOKAI) No. 6660/1986 that various kinds of charge controlling agents are incorporated into a binder resin (First method), and in Japanese Patent Publication (KOKAI) No. 100242/1978 and Japanese Patent Publication (KOKAI) No. 79634/1979 that the surface of magnetic powders or the like is coated with a resin containing charge controlling agents (Second method).
In the first method the effect of the charge controlling agent is negligible, because the content of the magnetic powder in the carrier is too much (200 to 900 parts by weight) in comparison with the toner content, so that the magnetic powder strongly influence the polarity of the carrier even if the charge controlling agents are incorporated into the binder resin.
In the second method, as when the binder type carrier is coated with a coating resin containing charge controlling agents or a solution containing them, the carrier is dissolved by the coated resin or a solvent in the solution, the application of the second method to the binder type carrier is substantially impracticable. Therefore, this method is usually applied to inorganic magnetic powder such as iron powder, magnetite powders, ferrite powder and the like or other carriers having a core of material insoluble with solvent, for example glass core. Thus, the second method is not suitable for binder type carriers.
SUMMARY OF THE INVENTION
The present invention provides a binder type carrier usable for development by magnetic brush, which can be controlled in the polarity of charge. The binder type carrier of the present invention is produced by adhering charge controlling agents on the surface of the core essentially consisting of magnetic powders and thermoplastic resins.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to binder type carriers which comprise cores essentially consisting of magnetic powders and thermoplastic binder resins, and charge controlling agents adhered on the surface of the cores.
The binder type carriers of the present invention can be prepared by firmly adhering charge controlling agents on the surface of cores which are conventional binder type carriers essentially consisting of thermoplastic binder resins and magnetic powders.
The cores used in the present invention may be a well known one, for example, the binder type carrier as described in Japanese Patent Publication (KOKAI) No. 66134/1979, in which magnetic powders having a particle size of from 0.01 to 2 micron meters are dispersed in binder resins and bound therein. The descriptions in the specifications for the above patent applications are incorporated into the present invention. A preferable binder type carrier to the present invention has a particle diameter of from 20 to 100 micron meters, especially 50 to 70 micron meters.
The magnetic powders dispersed in the binder resins may be any one having a volumetric specific resistance of more than 10 4 ohm cm, and a magnetization intensity of from 40 emu/g to 90 emu/g, especially from 60 emu/g to 80 emu/g, which may include iron powders, ferrite powders, magnetite powders, and the like. Particle size of the magnetic powders may be from 0.01 to 2 micron meters, preferably from 0.05 to 1 micron meters.
The binder resins usable in the present invention include polymers having a polar group such as carboxy group, hydroxyl group, glycidyl group, amino group and the like, derived from acid monomer having a polymerizable unsaturated bond, for example, acrylic acid, methacrylic acid, maleic acid, itaconic acid, and the like; hydroxyl group-containing monomer such as mono- or polypropylene glycol monoacrylate, mono- or polypropylene glycol monomethacrylate, mono- or polyethyleneglycol monoacrylate or methacrylate and the like; amino group-containing monomer such as dialkylaminoalkyl acrylate or methacrylate, e.g. dimethylaminoethyl methacrylate; epoxy group-containing monomer such as glycidyl acrylate or methacrylate; polymers derived from a monomer having no polar group, for example alkyl esters of unsaturated carboxylic acid monomers such as methyl acrylate or methacrylate, ethyl acrylate or methacrylate, diethyl maleate and the like; and vinyl aromatic monomers such as styrene, methyl styrene, ethyl styrene vinyl naphthalene and the like. These polymers may be derived from the copolymerization of the exemplified monomers and/or others.
Other group of polymers usable in the present invention may be polyesters. Such polyesters may be derived from the esterification of polyols and poly-acids, for example, as polyols there are exemplified diols such as ethyleneglycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropyleneglycol, triethylene glycol, polypropylene glycol, 1,4-butanediol, aromatic diols such as p,p'-isopropylidenediphenol (bisphenol A), precursor of diols such as lactones, partially esterified polyols such as fatty acid monoglycerides; triols or tetraols; and addition products of alkylene oxides to aliphatic or aromatic compounds having two or more active hydrogen atoms, such as diols, amines, alkanolamines, dithiols and the like. Most preferable polyols are diols and addition products of ethylene oxide and/or propylene oxide. As the poly-acids there are exemplified di-carboxylic acids, tricarboxylic acids or others. The di-carboxylic acids may include terephthalic acid, isophthalic acid, maleic acid, fumaric acid, itaconic acid, malonic acid, succinic acid, alkylsuccinic acids, glutaric acid pimeric acid, adipic acid, sebacic acid, and the like. As tri-carboxylic acid may include trimellitic acid and the like.
Other groups of the polymers usable as a binder resin of the present invention may include maleic alkyd resin, maleic oil, elastomer resin, for example, resin partially containing diens such as butadiene, isoprene, chloroprene and the like; and epoxy resin and so on.
These polymers may be mixed to give suitable properties as a binder resin.
The binder resins according to the present invention preferably has a melting point of from 80 to 180 l ° C., elasticity of from 100° to 160° C., and glass transition temperature of from 55° to 70° C.
The ratio of the binder resins to the magnetic powders is preferably 100 parts by weight to 200-900 parts by weight. If the magnetic powders are mixed less than 200 parts by weight, sufficient magnetic intensity cannot be effected whereas in case of more than 900 parts by weight obtained binder type carriers become so brittle to be used as a carrier.
In order to prepare the cores (i.e. conventional binder type carriers) to be used in the production of the carrier of the present invention any conventional manner may be used, for example, binder resin is sufficiently mixed with magnetic powders under higher temperature than the melting point of the binder resins, cooled, smashed and sifted to a suitable particle size.
The cores preferably have a particle size of from 20 to 100 micron meter, more preferably 30 to 70 micron meter as a weight average particle size, and a volumetric specific resistance of more than 10 8 ohm cm, more preferably more than 10 13 ohm cm.
According to the present invention charge controlling agents are firmly adhered on the surface of the cores.
The charge controlling agents may include any inorganic materials or organic materials which can give an electrical charge under friction with a toner, for example, metal oxides such as superfine silica, superfine titanium oxide, superfine alumina and the like; oily dyes containing metal alloy; nigrosine dyes; quaternary ammonium salts; nitrogen-containing cyclic compounds such as imidazols, pyridines or derivative thereof and the like; organic pigments; resinous materials containing fluorine atom, chlorine atom, nitrogen atom and the like.
The particle size of the charge controlling agents may be 0.02 to 15 micron meter, more preferably 0.1 to 10 micron meter, which is preferably 1/1000 to 1/10 of the particle size of non-coated carriers to be covered therewith. The preferable amount of the charge controlling agents is 0.1 to 10 % by weight based on the weight of the cores more preferably 1 to 5 % by weight.
The binder type carriers of the present invention may be prepared by mixing the cores with charge controlling agents in a vessel equipped with an instantaneously heating device and a mixing blade to dust the charge controlling agents on the surface with the cores, and heating the mixture on at least the surface of the cores, for instance, by means of high friction under vigorous mixture or by means of microwave to weld the charge controlling agents on the surface of the cores. A suitable apparatus to adhere the charge controlling agents on the carrier is, for example, Henshel mixer, Hybridizer available from Narakikai Seisakusho K.K. Of course, this method is only an example, but any manners, device or means are applicable to prepare the binder type carriers of the present invention.
The binder type carriers of the present invention may contain other materials which are usually used in a conventional binder type carrier.
The present invention shall be illustrated by the following examples, but it should not be interpreted as restricted by the descriptions of the examples.
Example 1
Synthesis of Binder Resin (1):
Into four necks flask equipped with a thermometer, a stirrer of stainless steel, a condenser and an N 2 -inlet hydroxyphenyl)propane (490 g), polyoxyethylene(2.2 mol)-2,2-bis(4-hydroxyphenyl)propane (190 g), terephthalic acid (170 g), n-dodecylsuccinic acid (320 g) and dibutyltin oxide (0.05 g), which were heated to 270° C. on a mantle heater under nitrogen atmosphere to allow them to react. When the generation of water had not been observed, trimellitic acid (58 g) was added, and the reaction was continued. When the acid value of the reaction mixture becameto 9 (mg KOH/g), the reaction mixture was cooled to stop the reaction. The obtained polyester had an acid value of 9 mg KOH/g, OH value of 16 mg KOH/g, a melting point (Tm) of 124° C., a viscosity (η 100 )3×10 6 poise, -d(log η)/dT: 4.0×10 2 , which were determined by a flow tester, and a moisture absorptivity of 0.66 %.
Preparation of Core A:
After following materials described hereinafter were sufficiently mixed, the mixture was blended under heating, cooled, smashed and classified to give the Core A.
______________________________________formulation of Core A parts by weight______________________________________polyester resin prepared in the above 100carbon black (MA #8: available fromMitsubishi Kasei Kogyo K.K.) 2silica (Aerosil #200: available fromAerosil K.K.) 1.5Zn type-ferrite (max. magnetic intensity:72 emu/g, Hc: 110, a vol. spec.resistance: 3 × 10.sup.8 Ωcm 600______________________________________
The average particle size of the Core A is 61 μm
Preparation of Carrier I:
The Core A prepared by the above process (100 parts by weight) and nigrosine dye (Bontron N-01: available from Orient Kagaku Kogyo K.K.) (3 parts by weight) were charged into a Henshel mixer (capacity: 10 liter), stirred at a revolution rate of 2,000 rpm for 2 minutes to uniformly dust the nigrosine all over the Core A. The dusted Core A was dispersed into anair flow heated at 320° C., and held for about 1 to 3 seconds to partially melt the surface of the Core A, and the dye was welded thereon to give a Carrier I.
Example 2
The Core A (100 parts by weight) and metal-containing dye (Bontron S-34: available from Orient Kagaku Kogyo K.K.) (2 parts by weight) were charged into a Henshel mixer (capacity: 10 liter), and blended at a revolution rate of 2,000 rpm for 2 minutes to uniformly dust the dye all over the surface of the Core A.
The dusted Core A was partially heated for 20 minutes at 1,000 rpm to weld the metal-containing dye on the core surface to give Carrier II.
Example 3
Carrier III was obtained by mixing the Core A (100 parts by weight) and colloidal silica (R-972: available from Nippon Aerosil K.K.) (2 parts by weight), stirred and then instantaneously heated according to Example 1.
Example 4
Carrier IV was obtained by mixing the Core A (100 parts by weight) and quaternary ammonium salts (P-51: available from Orient Kagaku Kogyo K.K.) (3 parts by weight), stirred and then instantaneously heated according to the same manner as in the Example 1.
Example 5
Carrier V was obtained by mixing the Core A (100 parts by weight) and nigrosine (Bontron N-01: available from Orient Kagaku K.K.) (0.5 parts by weight), stirred and then instantaneously heated according to the same manner as in the Example 1.
Example 6
Carrier VI was obtained by mixing the Core A (100 parts by weight) and nigrosine (Bontron N-01: available from Orient Kagaku K.K., 10 parts by weight), stirred and then instantaneously heated according to Example 1.
Example 7
Synthesis of Binder Resin (2): Styrene (650 g), n-butyl methacrylate (300 g), acrylic acid (5 g), azobisisobutyronitrile (20 g) and benzene (1000 g)were charged into a four-necks flask equipped with a thermometer, a stirrerof stainless steel, a condenser, and a nitrogen-inlet, and heated at 70° C. on a mantle heater to react under nitrogen circumstances for6 hours. After the reaction the benzene was removed under reduced pressure to give a solid resin (2), which had an acid value of 39 mg KOH/g, a glasstemperature of 62° C., melting point (Tm) of 125° C., and a viscosity (at 100° C.:η 100 ) of 4×10 6 poise and -d(log η)/dT of 3.8×10 2 when determined by a flow tester.
Preparation of Core B:
Following components were sufficiently mixed, blended under heating, cooled, smashed and then classified to give Core B.
______________________________________Components parts by weight______________________________________styrene-acryl resin (2) 100carbon black (MA #8: availablefrom Mitsubishi Kasei K.K.) 2silica (Aerosil #200: availablefrom Aerosil K.K.) 1.5Zn type ferrite (maximum magnetizedintensity: 72 emu/g, Hc: 110,vol. spec. resistance: 3 × 10.sup.8 Ωcm) 600______________________________________
The obtained Core B has an average particle size of 6.3 micron meter.
Preparation of carrier VII:
Core B (100 parts by weight), nigrosine (Bontron N-01: available from Orient Kagaku Kogyo K.K.) (3 parts by weight) were charged into a Henshel mixer (capacity: 10 liter), and mixed at 2,000 rpm for 2 minutes to uniformly dust the nigrosine all over the Core B. The dusted Core B was dispersed in an air flow heated at 320° C., and the surface thereofwas partially and instantaneously heated for about 1 to 3 seconds to weld the nigrosine on the surface of the Carrier B to give the Core VII.
Comparative Example 1
The Core A of Example 1 was used as it is as a conventional carrier for theComparative Example 1.
Comparative Example 2
The Core B prepared in Example 7 was used as it is as a conventional carrier for the Comparative Example 2.
Preparation of Toner:
Hymer SBM 600 (styrene-acrylic copolymer: available from Sanyo Kasei Kogyo K.K.) (100 parts by weight), carbon black (MA #100: available from Mitsubishi Kasei Kogyo K.K.) (5 parts by weight) were sufficiently mixed, blended by a mixer having three rollers, and then finely smashed by a jet pulverizer. The smashed mixture was sifted to fine particles and coarse particles, and obtained toners having a particle size of 5-25 micron meters and an average particle size of 13 micron meters.
Determination of Charge Amount:
Developers were prepared by mixing the toner (3 g) and the carrier (27 g) of each example and comparative example, and then the charge amount of theobtained developers was determined just after each developer was stirred at120 rpm for 10 minutes. The results were shown in Table 1.
Evaluation of durability against copying:
The durability of the developers prepared from the Carriers I - VII against60,000 sheets copying was evaluated using Copying Machines EP-470Z and EP-650Z (available from Minolta Camera K.K.). Neither fog was observed in the copied image obtained using the Carriers I-VII, nor stains by the toner on the photosensitive member, whereas with respect to the developer of the Comparative Examples 1 and 2 the charge amount was insufficient to be determined.
TABLE 1______________________________________ charge binder resin charge controlling amountexample (100 parts) agents (μc/g) fog______________________________________1 polyester nigrosine (3 parts) -15 non resin (Bontron N-01)2 polyester metal-containing +13 non resin dye (2 parts) (Bontron S-34)3 polyester colloidal silica +12 non resin (2 parts) R-9724 polyester quaternary ammonium -12 non resin salts (3 parts) P-515 polyester nigrosine (0.5 -10 non resin parts) Bontron N-016 polyester nigrosine (10 -16 non resin parts) Bontron N-017 styrene- nigrosine (3 parts) -13 non acrylic resin (Bontron N-01)Compar. polyester non +2 --Ex. 1 resin2 styrene- non -1 -- acrylic resin______________________________________
As apparent from the above results, the binder type carriers of the presentinvention can control the polarity of the charge thereon, plus or minus, bythe action of the charge controlling agents, in addition to which the tonerused together with the carriers can be sufficiently charged. The copied image produced by the developer containing the carrier of the present invention has no substantial fogs even after durability test of 60,000 sheets. | The present invention relates binder type carriers, the surface of which is firmly adhered with charge controlling agents, by which the elastic charge of the carriers can be controlled to a desirable polarity and a level without the influence of the chargeability inherent to the magnetic powders themselves. | 6 |
BACKGROUND OF THE INVENTION
The U.S. government has rights in this invention by virtue of Contract No. N0014-75-C-0880 and Contract No. N00014-82-K-0737 from the Office of Naval Research.
Presently available solid state microelectronic devices consist of microcircuits with discrete circuit elements such as monolithic integrated circuits, transistors, diodes, resistors, capacitors, transformers, and conductors mounted on an insulating substrate. Thin film hybrid microcircuits are formed by vapor deposition of conductors, such as copper and gold, and resistors, such as tantalum, nichrome, and tin oxide onto a passive or insulating substrate such as silicon dioxide. An exact conductor pattern is obtained by masking or photolithographic etching. The entire circuit is subsequently encased with an epoxy dip to protect against moisture and contamination.
Modern integrated circuit devices, even highly miniaturized very large scale integrated devices (VLSI), are responsive only to electrical signals. There is now considerable interest in interfacing microelectronic devices with chemical and biological systems and it is therefore highly desirable to provide a microelectronic device that is responsive to such chemical or biological inputs. Typical applications for these devices include sensing of changes in pH and molar concentrations of chemical compounds, oxygen, hydrogen, and enzyme substrate concentrations.
Applicant is not aware of any apparatus or system which allows a direct interface between a microelectronic device sensitive to chemical imputs and a microminiature electrical circuit. Devices have been made on a larger scale which are sensitive to chemical input. These devices include such well known apparatus as pH sensors. Work in this area has recently centered around the use of electroactive polymers, such as polypyrrole or polythiophene. These compounds change conductivity in response to changes in redox potential. Recently, a polymeric semiconductor field effect transistor has been disclosed in a Japanese Pat. No. 58-114465. As described in this patent, polymers such as trans-polyacetylene, cis-polyacetylene, polypyrrole, and polyvinyl phenylene have been used as inexpensive substitutes for single crystal silicon or germanium in making a semiconductor field effect transistor. There is no recognition of the unique properties of these polymers in this patent and, in fact, the polymers are treated as semiconducting material even though the properties of the polymers are distinctly different from that of silicon or germanium. The polymers are used as substitutes for semiconducting materials sensitive to electrical signals for uses such as in memory storage. Disadvantages to the FET as disclosed are that it is unstable and has a short useful life.
It is therefore an object of the present invention to provide a process for producing microelectronic devices responsive to chemical input which can be incorporated into microelectronic systems which are responsive to electrical input.
A further object of the present invention is to provide a process for constructing molecule-based microelectronic devices on silicon substrates which can easily be integrated with solid state silicon devices for signal processing.
Still another object of the invention is to provide small, sensitive, and specific microelectronic devices with very low power requirements.
A further object of the invention is to provide diodes, transistors, sensors, surface energy storage elements, and light-emitting microelectrode devices which can be controlled by molecular-level changes in electroactive polymer components.
SUMMARY OF THE INVENTION
The present invention is a process for making microelectronic devices which can be controlled by molecular-level changes in electroactive polymer components. These devices are fabricated by functionalizing electrodes formed by deposition of metal on silicon dioxide substrates using conventional masking and photolithography techniques with polymers whose physical properties change in response to chemical signals. The key features are the small dimension of the electrodes and the small spacing, in the range of less than five microns, between them.
In one emboidment, analogue of a solid state transistor, wherein a transistor is defined as a material whose resistance can be adjusted by an electrical signal, is formed from an array of gold microelectrodes derivatized with a redox polymer such as polypyrrole. When polypyrrole is oxidized, it conducts an electrical current between the microelectrodes. As in a solid state transistor, the current between the two outer microelectrodes of the array can be varied as a function of the potential of the polymer electrically connecting the electrodes in a manner analagous to the "gate" of a transistor. As the potential is altered, the oxidation or reduction of the polypyrrole can be effected. This device amplifies the very small signal needed to turn the polypyrrole from its reduced and insulating state to its oxidized and conducting state. Further variations are possible using additonal polymers with different redox potentials.
In a second embodiment, a diode is fabricated on a silicon dioxide-silicon substrate from an array of two or more microelectrodes separated from each other by a distance of 2 microns or less, individually functionalized with a chemically responsive polymer, such as a redox polymer. Examples of redox polymers are polypyrrole, poly-N-methylpyrrole, polythiophene, poly-3-methylthiophene, polyvinylferrocene, derivatized styrene and polyaniline. As many different polymers may be used as there are pairs of microelectrodes. Since the polymers respond at different potentials, each pair of electrodes can be effectively isolated from the other microelectrodes.
In yet another embodiment, a microelectronic device with transistor or "triode-like" properties is fabricated by deposition of polyaniline onto an array of two or more gold microelectrodes. Polyaniline, a redox polymer, has the unusual property of being insulating at an electrical potential, less than +0.1 V vs. SCE in aqueous 0.5 M NaHSO 4 , greater than 10 6 times more conducting at a slightly higher electrical potential, +0.4 V vs. SCE in 0.5 M NaHSO 4 , and insulating at a higher electrical potential, +0.7 V vs. SCE in 0.5 M NaHSO 4 . The exact potential at which the polyaniline is conducting or insulating is determined by the medium, the amount of polyaniline connecting the electrodes, and interactions with other polymers. This device is particularly useful as an electrical switch between a specific range of potentials or as a pH or other chemical sensor. The device may be further modified for use as an oxygen or hydrogen sensor by connecting the polyaniline to a noble metal electrode such as a platinum electrode or by dispersing particles of noble metals such as palladium into the polyaniline.
Other specific embodiments of the present invention include surface energy storage elements and light-emitting microelectrodes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a surface energy storage device wherein electrical energy is used to charge the device by reducing a polyviologen polymer, (PQ 2+/+ ) n , and oxidizing a polyvinylferrocene polymer, (FeCp 2 +/o) n .
FIG. 2 is a cross-sectional view of a molecule-based transistor consisting of three gold microelectrodes, derivatized with polypyrrole and immersed in electrolyte, with a schematic showing how the electrical potential of the gate is set using a potentiostat with a counter electrode and a saturated calomel reference electrode (SCE).
FIG. 3 is a graph showing the output characteristics of the transistor of FIG. 2 as I D , the current between source and drain, as a function of V D , the potential between source and drain, at various fixed gate potentials, V G .
FIG. 4a is a cross-sectional view of a molecule-based transistor, consisting of two gold electrodes coated with polyvinylferrocene, (FeCp 2 +/o ) n , and polyviologen, (PQ 2+/+ ) n , and functionalized with a quinone-based polymer, (Q/QH 2 ) n , having a pH-dependent redox potential which is more negative or positive than the potential of the viologen polymer, depending on the pH.
FIG. 4b is a schematic of the effect of pH variation on the polymers in the transistor of FIG. 4a and shows the approximate relationship of the redox potentials.
FIG. 5 is a cross-sectional view of a molecule-based diode consisting of two gold microelectrodes derivatized with two polymers of different redox potentials.
FIG. 6 is a cross-sectional view of an array of eight gold microelectrodes derivatized with different amounts of polypyrrole.
FIG. 7 is a graph of cyclic voltammograms at 100 mV/s for an array like that in FIG. 6 in CH 3 CN/0.1M [n-Bu 4 N]ClO 4 . The bottom portion of the sketch is the expected result based on the derivation procedure and electrochemical response.
FIG. 8a is a graph of the potential, V vs. SCE, measured in CH 3 CN/0.1M [n-Bu 4 N]ClO 4 , of five gold microelectrodes connected with polypyrrole when one is under active potential control at -1.0 V vs. SCE and one is at a positive potential at which the polypyrrole is expected to be conducting.
FIG. 8b is a graph of the potential, V vs. SCE, of five gold microelectrodes connected with polypyrrole where only one electrode is under active potential control.
FIG. 9 is a graph of the current, i, measured between electrodes, versus applied potential, V appl vs. SCE, for two adjacent microelectrodes connected with polypyrrole as a function of V set , where V set is the fixed potential vs. SCE of one of the two electrodes, and V appl , where V appl is the potential of the other electrode.
FIG. 10 is a graph comparing the diode characteristics for two microelectrodes connected with (a) polypyrrole and (b) poly-N-methylpyrrole where the fixed potential, V set , in (a) is -1.0 V vs. SCE and in (b) is -0.6 V vs. SCE.
FIG. 11 is a cross-sectional view of a light-emitting pair of microelectrodes wherein the two gold microelectrodes are connected by a polymer such that application of a voltage, approximately 2.6 V, results in emission of light characteristic of an excited tris, 2,2'-bipyridine ruthenium (II) complex, Ru(bpy) 3 2+ .
FIG. 12 (inset) is a cross-sectional view of a device fabricated from two polyaniline-coated gold microelectrodes wherein V D is the potential between one microelectrode "source" and another microelectrode "drain" at a fixed gate potential, V G , controlled relative to an aqueous saturated calomel reference electrode (SCE).
FIG. 12a is a graph of the drain current, I D , in microamps versus the drain voltage, V D , in mV for the device shown in the inset at various values of V G , where the charge passed in setting the gate to a potential where there is conductivity between source and drain can be regarded as an input signal.
FIG. 12b is a graph of I D vs. V G at a fixed V D of 0.18 V for the device shown in the inset.
FIG. 13 is a graph of a cyclic voltammogram at 100 mV/s for a devcie such as the one described in FIG. 12 (inset) when V G is +0.3 V vs. SCE and V D is 20 mV.--is at 0 hours and . . . is after 16 hours.
FIG. 13 (inset) is a graph of I D versus time in hours when V D is at 20 mV, V G is at +0.3 V vs. SCE, and the electrolyte is 0.5M NaHSO 4 at pH 1.
FIG. 14a is a graph of the I D vs. V G for a device such as the one shown in FIG. 12 (inset), where V G is varied from -0.2 V vs. SCE to +0.8 V vs SCE.
FIG. 14b is a graph of resistance in ohms versus V G for a device shown as the one in FIG. 12 (inset).
FIG. 15 is a graph for a device such as the one shown in FIG. 12 (insert) of I D in microamps versus V D in mV at a V G of -0.2 V vs. SCE, a potential at which polyaniline is reduced and insulating.
FIG. 16 is a graph of I D versus time in seconds at V D of 0.18 V for a device such as the one shown in FIG. 12 (inset) for a V G step of -0.2 to +0.3 V vs. SCE.
FIG. 17 is a cross-sectional view of a polyaniline-connected microelectrode array connected externally to a macroscopic indicator electrode.
FIG. 18 is a cross-sectional view of a polyaniline-connected microelectrode array consisting of three gold microelectrodes connected to a counter-electrode, reference electrode, and potentiostat.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a process for producing molecule-based microelectronic devices consisting of two or more microelectrodes separated by a small dimension, which can be contacted individually and independently functionalized using electroactive polymers with specific properties that are responsive to chemical and/or electrical signals. Examples of one group of electroactive polymers are redox polymers which are insulating when reduced and conducting when oxidized.
The microelectrodes are small, typically on the order of 2 to 5 microns wide by 50 to 150 microns long by 0.1 to 0.15 microns thick, although even smaller electrodes may be utilized, and made of inert, electrically conductive material such as gold, silver, palladium, gold-platinum, and gold-palladium or other metals that are electrochemically inert. The conductor should be easily deposited and have low electrical resistance, good adhesion to the substrate, stability, and ability to be functionalized.
These electrodes are positioned on an inert substrate. An example of a preferred substrate would be oxidized silicon wafers made by growing a 4500 Angstroms to 10,000 Angstroms thick SiO 2 layer on <100> Si. Devices made according to the present invention on silicon wafers may be easily integrated into presently available solid state microelectronic devices, most of which are also produced on silicon wafers.
The small separation between electrodes, typically on the order of 0.1 to 2 microns, combined with the use of electroactive polymers with specific properties, is crucial to the invention. The smallest inter-electrode space technically feasible is preferred. The small inter-electrode space allows high current densities. As the distance between microelectrodes is increased, output decreases and "noise" increases. The direction of current flow, the ability to respond to a chemical signal such as a change in pH, the rate of response, the degree of response, the storage of energy, and the ability to place other pairs of electrodes in close proximity without interference is due to the choice, deposition, degree of separation and quantity of polymer.
Various groups of polymers known to those skilled in the art are suitable for use in the present invention. The requirements for such polymers are that they can be electrochemically deposited on individual electrodes and polymerized and that they can respond to a signal, in a reversible manner, in a way which can be electrochemically detected. Such materials are described by R. W. Murray in Electroanalytical Chemistry, Vol. 13, Edited by A. J. Bard (Marcel Dekker, N.Y., 1984).
Suitable electrochemically polymerizable materials for use in the present invention include redox polymers. Examples of such polymers are polypyrrole, polyaniline, poly-N-methylpyrrole, polythiophene, poly-3-methylthiophene and polyvinylferrocene (poly vinyl dicyclopentadienyliron). Styrene and vinyl aromatic derivatives such as vinyl pyridine, vinyl, 2,2'-bipyridine and metal complexes of these derivatives, are also useful since they can be electrochemically polymerized and may be derivatized with a number of reagents, including biologically active agents such as enzymes and ionophores that complex with ions such as lithium and calcium.
Using two or more electrodes connected with one polymer, a transistor-like device may be fabricated. By choosing two or more polymers with different redox potentials, adjacent electrodes may be electronically isolated or made to function as diodes or surface energy storage units.
For polypyrrole and poly-N-methylpyrrole, the oxidized materials are electronic conductors. The conductivity varies by more than 10 10 depending on the redox state of the polymers. The consequence of the very large difference in conductivity with redox state is that the potential drop can occur across a very small fraction of length of the connecting polymer when one microelectrode is held at a potential where the polymer is reduced and insulating and the other is held at a potential where the polymer is oxidized and conducting. For example, polypyrrole is insulating at approximately -0.4 V vs. SCE potential but becomes conducting at positive potentials up to any positive potential at which the polypyrrole is durable. The actual conductivities of the oxidized polymers, mesured in CH 3 CH/0.1M [n-Bu 4 N]ClO 4 , of polypyrrole and poly-N-methylpyrrole, respectively, are approximately 10 -2 ohm -1 ·cm -1 and 10 -4 to 10 -5 ohm -1 ·cm -1 .
In contrast to polypyrrole, polyaniline can be made conducting by either a positive or a negative shift of the electrochemical potential, since polyaniline is essentially insulating at sufficiently negative (negative of 0.0 V vs. SCE) or positive (positive of +0.7 V vs. SCE) electrochemical potentials. As a result, a polyaniline-based device responds to a signal in a significantly different way from solid state transistors where the current passing between source and drain, I D , at a given source to drain voltage, V D , does not decrease with increasing gate voltage, V G . The conductivity of polyaniline has been measured to span eight orders of magnitude and is sensitive to pH and other chemical parameters.
The potential at which a polymer exhibits a sharp change in conductivity due to oxidation is the threshold potential, V T . V T can be manipulated by using different monomers or different redox polymers, and by varying the medium to be "seen" by the polymer.
Other polymers which are useful in the present invention include redox polymers known to be electrochromic materials, compounds which change color as a result of electrochemical reactions. Examples of such materials are polyvinylferrocene, polynitrostyrene, and viologens. Viologens, described by Wrighton et al in U.S. Pat. Nos. 4,473,695 and 4,439,302, the teachings of which are incorporated herein, are compounds formed from 4,4'-bipyridinium which may be polymerized and covalently bonded or otherwise confined to the surfaces of electrodes. Viologens such as dialkyl-4,4'-bipyridinium di-cation and associated anions, dichloride, dibromide, or di-iodide, forming contrasting colors when oxidized or reduced. Since each monomer unit of viologen has a 2+ charge which is balanced in the presence of two halide counter ions, the counter ions can be replaced with a complex ion such as PtCl 6 2- which can then be reduced to yield embedded elemental Pt(O) in highly dispersed form. An enzyme such as hydrogenase can also be immobilized onto or throughout the redox polymer to equilibrate the redox polymer with the enzyme substrates.
Substituted viologens are useful for photogeneration of hydrogen from aqueous electrolytes, for reduction of metal-containing macromolecules, and on p-type silicon photocathodes in electrolytic cells.
The invention is further illustrated by the following non-limiting examples. Devices in these examples were constructed according to the procedure outlined below, with minor variations.
FABRICATION OF MICROELECTRODE ARRAYS
Microelectrodes arrays were fabricated in the Massachusetts Institute of Technology Microelectronics Laboratory in the Center for Materials Science and Engineering which includes a class 100 clean room and is equipped to meet the specialized requirements for the production of solid state microelectronic devices such as "silicon chips".
A two-mask process was designed. The first mask was made for a metal lift-off procedure to form microelectrodes, leads, and contact pads. The second mask was made to pattern a photoresist overlayer leaving a 50 to 140 micron length of the microelectrodes and the contact pads exposed.
A microelectrode array was designed using the Computer Aided Design Program HPEDIT at a Hewlett Packard Model 2648A graphics terminal on a DEC-20. The design file was translated into Caltech Intermediate Form (CIF). This CIF file was translated to Mann compatible code and written on magnetic tape. Masks for photolithography were made from the file on magnetic tape using a Gyrex Model 1005A Pattern Generator. E-K 5"×5"×0.090" Extra Flat high resolution glass emulsion plates were used to make the photolithography masks. The emulsion plates were developed by a dark field process.
P-Si wafers of <100> orientation, two inches in diameter and 0.011 inches thick, obtained from Wacker Corp. were used as substrates upon which to fabricate the microelectrode arrays. The silicon wafers were RCA cleaned in a laminar air flow hood in the class 100 clean room. The wafers were immersed in hot aqueous 6% by volume H 2 O 2 /14% by volume aqueous NH 3 , briefly etched in hydrofluoric acid diluted 10:1 with deionized water, immersed in hot aqueous 6% by volume H 2 O 2 /14% by volume HCl, rinsed in deionized water (resistance greater than 14 Mohm·cm), and spun dry. The cleaned wafers were loaded immediately into an oxidation tube furnace at 1100° C. under N 2 . For examples 1 to 5, a dry/wet/dry/anneal oxidation cycle was used to grow a thermal oxide layer 4500 Angstroms thick. For example 6, a dry oxidation cycle was used to grow a thermal oxide 11,850 Angstroms thick. Oxide thicknesses were measured using a Gaertner Model L117 ellipsometer. The oxidized wafers were taken immediately to the photolithography stage.
Each oxidized wafer was flood-coated with hexamethyldisilazane and spun at 6000 rpm for 20 sec. For examples 1 to 5, one ml of MacDermid Ultramac PR-914 positive photoresist was syringed onto each wafer. The wafer coated with resist was spun for 30 sec at 4000 rpm and then prebaked 35 min at 90° C. For example 6, one ml of Shipley 1470 positive photoresist was syringed onto each wafter and the wafer spun for 30 seconds at 6000 rpm. The coated wafer was then prebaked 25 minutes at 90° C.
A GCA Mann 4800 DSW Wafer Stepper was used to expose the photoresist. The Mann uses the 405 nm line of a 350 W Hg arc lamp as a light source. The mask image is reduced 5:1 in the projection printing. For examples 1 to 5, an exposure time of 0.850 sec was used and the photoresist developed 60 sec in MacDermid Ultramac MF-62 diluted 1:1 with deionized water. For example 6, the wafer was exposed for 1.2 seconds and developed 60 seconds in Shipley 312 developer diluted 1:1 with dionized water. The developed wafers were then cleaned in a planar oxygen etching chamber at 75-100 W forward power in 20 mtorr of oxygen for 15 seconds.
A bilayer metallization was performed. A MRC 8620 Sputtering System was used in preparing the microelectrode arrays of examples 1 to 5. The bilayer metallization of the wafers used in example 6 was performed in a NRC 3117 electron beam evaporation system. Wafers were placed on a quartz plate that was freshly coated with chromium. The wafers were backsputtered 2 min at 50 W forward power in an argon plasma at 5 mtorr. Chromium was sputtered at 50 W forward power to produce a layer of chromium. The layer on the wafers in examples 1 to 5 was 200 Angstroms thick. The layer in example 6 was 50 Angstroms thick. Gold was then sputtered at 50 W forward power to produce a layer 1000 Angstroms thick. Chromium serves as an adhesion layer for the gold. The combined chromium/gold thickness of the wafers used in example 6 was measured to be 1052 Angstroms on a Dektak II surface profile measuring device.
At this point, the chromium/gold was in direct contact with the SiO 2 substrate only in the areas that were to form the microelectrodes, leads, and contact pads on the photoresist in all other areas. The chromium/gold on photoresist was removed by a lift-off procedure: the metallized wafers were immersed in warm acetone, in which soft-baked positive photoresist is soluble, for 75 minutes for the wafers used in examples 1 to 5 and 5 minutes for the wafers used in example 6. The wafers used in examples 1 to 5 were briefly sonicated in acetone to remove the metal between microelectrodes, dried, and then cleaned of residual photoresist in a planar oxygen plasma etching chamber at 200 W forward power in 50 mtorr oxygen for 60 sec.
The wafers used in example 6 was blasted with acetone from a Paasche air brush with N 2 at 70 psi, sonicated for 30 minutes in acetone, then rinsed with acetone and methanol before drying. The wafers were then cleaned in a mixture of hot aqueous 6% by volume H 2 O 2 /14% by volume aqueous NH 3 , rinsed in deionized water (greater than 14 megaohm·cm), and spun dry. The wafers were then baked at 180° C. for 40 minutes before repeating the photoresist spin coating process. The wafers were again prebaked at 90° C. for 25 minutes and then exposed in a Karl Suss America Inc. Model 505 aligner for 11 seconds, using a dark field mask. The photoresist was developed in Shipley 312 developer diluted 1:1 with deionized water to expose the bond pads and the array of microelectrode wires. The exposed areas were cleaned of residual photoresist in the oxygen plasma etching chamber at 75-100 W for 1 minute. The remaining photoresist was hardbaked at 180° C. for 15 hours.
Wafers were then baked at 180° C. for 40 minutes before repeating the photoresist spin coating process. The wafers were again prebaked at 90° C. for 25 minutes and then exposed in a Karl Suss America Inc. Model 505 aligner for 11 seconds, using a dark field mask. The photoresist was developed in Shipley 312 developer diluted 1:1 with deionized water to expose the bond pads and the array of microelectrode wires. The exposed areas were cleaned of residual photoresist in the oxygen plasma etching chamber at 75-100 W for 1 minute. The remaining photoresist was hard baked at 180° C. for 15 hours.
Individual die (chips) were scribed and separated. The chips were mounted on TO-5 headers from Texas Instruments with Epoxi-Patch 0151 Clear from Hysol Corp. A Mech-El Ind. Model NU-827 Au ball ultrasonic wire bonder was used to make wire bonds from the chip to the TO-5 header. The leads, bonding pads, wire bonds, and header were encapsulated with Epoxi-Patch 0151. The header was connected through a TO-5 socket to external wires. The external wires were encased in a glass tube. The header was sealed at the distal end of the glass tube with heat shrink tubing and Epoxi-Patch 1C white epoxy from Hysol Corp.
Prior to use as a microelectrode array, the array was tested to establish the leakage current between the various electrodes of the array. Arrays characterized as usable have a measured resistance between any two electrodes of greater than 10 9 ohms in non-aqueous electrolyte solution containing no added electroactive species. In many cases only a fraction of the electrodes of an array were usable. Prior to use in experimentation the microelectrode arrays were tested further in aqueous electrolyte solution containing 0.01M K 3 [Fe(CN) 6 ] and 0.01M K 4 [Fe(CN) 6 ] or with [Ru(NH 3 ) 6 ]Cl 3 to establish that the microelectrodes give the expected response. Typically, a negative potential excursion to evolve H 2 cleaned the gold surface sufficiently to give good electrochemical response to the Fe(CN) 6 3-/4- or Ru(NH 3 ) 6 3+/2+ redox couples. The electrolyte used for electrical measurement was 0.1M NaClO 4 in H 2 O solvent, 0.5M NaHSO 4 , or 0.1M [n-Bu 4 N]ClO 4 in CH 3 CN solvent.
ELECTROCHEMICAL EQUIPMENT
Most of the electrochemical experimentation in examples 1 to 5 was carried out using a Pine Model RDE 3 bipotentiostat and potential programmer. In cases where two microelectrodes were under active potential control and a third was to be probed, a PAR Model 363 potentiostat/galvanostat was used in conjunction with the Pine Model RDE 3. All potentials were controlled relative to an aqueous saturated calomel reference electrode (SCE). Typically, electrochemical measurements were carried out under N 2 or Ar at 25° C.
For Example 6, most of the electrochemical experimentation was carried out using a Pine model RDE 4 bipotentiostat and potential programmer. In some cases where only a single potentiostat was needed a PAR Model 173 potentiostat/galvanostat and a PAR Model 175 universal programmer was used. Potential step experiments were carried out using the RDE 4 with a Tektronix type 564B storage oscilloscope as the recorder.
DERIVATIZATION OF MICROELECTRODES
In examples 1 to 5, the gold microelectrodes were functionalized by oxidation of 25-50 mM pyrrole or N-methylpyrrole in CH 3 CN/0.1M [n-Bu 4 N]ClO 4 . The polypyrrole was deposited at +0.8 V vs. SCE, and the poly-N-methylpyrrole was deposited at +1.2 vs. SCE. The deposition of the polymer can be effected in a controller manner by removing the array from the derivatization solution after passing a certain amount of charge. Electrodes were then examined by cyclic voltammetry in CH 3 CN/0.1M [n-Bu 4 N]ClO 4 to assess the coverage of polymer and to determine whether the polymer coated two or more electrodes resulting in a "connection" between them.
Prior to use as a microelectrode array, each microelectrode wire in the devices used in example 6 was tested with an ohmmeter to make sure it was not shorted to any other wire on the device. Then each microelectrode was tested by running a cyclic voltammogram in 0.01M Ru(NH 3 ) 6 3+ /0.1M NaNO 3 /H 2 O. The microelectrodes were derivatized by oxidation of a stirred 0.44M aniline solution in 0.5M NaHSO 4 /H 2 O at pH 1. The polyaniline was deposited at +0.9 V vs. SCE. Electrodes were then examined by cyclic voltammetry in 0.5M NaHSO 4 at pH 1 to assess the coverage of polymer and to determine whether the polymer coated two or more electrodes resulting in a connection between them. Macroscopic gold electrodes were derivatized with polyaniline by the same procedure to accurately relate the thickness of polyaniline to cyclic voltammetry response and the charge passed in the anodic deposition. Typically, a portion of the gold flag was covered with grease prior to depositing the polyaniline over the exposed gold surface. The grease was then removed with CH 2 Cl 2 to give a well defined step from gold to polyaniline.
EXAMPLE 1
In one embodiment of the present invention, depicted in FIG. 1, a surface energy storage device 10 is constructed from two gold microelectrodes 12, 3 microns wide by 140 microns long by 0.12 microns thick, deposited on a 1 micron thick SiO 2 insulator 14 grown on a <100> Si substrate 16 and separated by a distance of 1.4 microns. Each microelectrode is individually coated with electrochemically deposited polymerized polymers, polyviologen 18 and polyvinylferrocene 20. Electrical energy can be used to charge the device by reducing the polyviologen, the (PQ 2+ ) n polymer, and oxidizing the polyvinylferrocene, the (FeCp 2 0 ) n polymer, according to the following reaction: ##STR1##
EXAMPLE 2
In another embodiment of the present invention, shown in FIG. 2, a molecule-based transistor 22 is fabricated from three gold microelectrodes separated by 1.4 microns, derivatized with polypyrrole 24. Typical coverage of the polypyrrole is 10 -7 mol/cm 2 of exposed gold, and the individual microelectrodes are electrically connected. The microelectrodes are wired so as to correspond to the drain 26, gate 28, and source 30 as in a conventional solid state transistor.
The properties of the device are characterized by immersing the device in an electrolyte, CH 3 CN/0.1M [n-Bu 4 N]ClO 4 , and measuring the current 32 between source 30 and drain 26, I D , as a function of the potential 34 between source and drain, V D , at various fixed gate potentials 36, V G . The results are shown in FIG. 3.
At values for V D of less than 0.5 V, the device is "off" when V G is held at a negative potential where the polypyrrole is expected to be insulating and I D is small. When V G is moved to potentials more positive than the oxidation potential of polypyrrole, approximately -0.2 V vs. SCE, the device "turns on" and a significant steady-state value for I D can be observed for modest values of V D . The close spacing of the microelectrodes allows an easily measurable current to pass between the source 30 and the drain 26 when V D is significant and V G is above the threshold, V T . V T , the gate potential at which the device starts to turn on, is approximately equal to the redox potential of polypyrrole. For V G more positive than V T , the value of I D increases at a given value of V D , in a manner consistent with the increasing conductivity due to an increasing degree of oxidation. At sufficiently positive values of V G , greater than or equal to +0.5 V vs. SCE, I D becomes insensitive to further positive movement of V G at a given value of V D , a result consistent with measurements of the resistance of the oxidized polypyrrole coated on a microelectrode array. A small range of V D values (0 to 0.2 V) is used to minimize electrochemical reactions at the source 30/polymer and drain 26 /polymer 24 interfaces.
A fraction of 10 -8 C of charge is required to obtain the maximum steady-state value of I D when V D is equal to 0.2 V with this device. The value of I D achievable with the device is 4×10 -5 C/s. It is apparent from these results that a small signal to the gate microelectrode can be amplified in much the same way that a small electrical signal cam be amplified with a solid state transistor. The major difference is that the turn on/turn off time in the molecule-based system is dependent on the rate of a chemical reaction rather than on electron transit times across the source to drain distance. For the molecule-based system, the properties such as V T and minimum turn on signal can be adjusted with rational variation in the monomer used to prepare the polymer. Use of smaller dimensions and materials other than polypyrrole can also lead to faster switching times.
EXAMPLE 3
As shown in FIG. 4a, a molecule-based pH sensor 40 can theoretically be fabricated using a two microelectrode array on a SiO 2 -Si substrate 42.
The two gold microelectrodes 44, 45 are coated with polyviologen 46, (PQ 2+/+ ) n , and polyvinylferrocene 48, (FeCp 2 +/o ) n , respectively, and then overlaid with another polymer 50 with a different pH dependent redox potential, such as a polyquinone, (Q/QH 2 ) n , whose redox potential is above the redox potential of the polyviologen at high pH and between that of the polyviologen and polyvinylferrocene at low pH.
The pH variation serves as the signal to the amplified. Varying the pH results in a variation in current passing between the two gold electrodes at a fixed potential difference with the negative lead to the viologen coated electrode. As shown by FIG. 4b, alteration of the pH changes the redox potential of polymer 50. Low pH acts to make it easier to reduce polymer 50. Current can flow between source 44 and drain 45 when the negative lead is attached to the polyviologen-coated gold microelectrode 44 and the positive lead is connected to the polyvinylferrocene-coated gold microelectrode 45 and the redox potential of the polyquinone is between the redox potentials of the two polymers 46 and 50 coating source 44 and drain 45. At a fixed potential difference, the current passing between the two microelectrodes 44 and 45 should depend on the pH of the solution contacting the polymer 50.
A pH sensor may also be affected by coating a microelectrode array with a polymer such as polyaniline. For a device consisting of two gold microelectrodes, 0.1 micron thick, 4.4 microns wide, and 50 microns long, separated by a distance of 1.7 microns, coated with a layer of polyaniline approximately 5 microns thick, changes in the pH of the surrounding medium markedly alter the conductivity. For example, the value of I D at V D equal to 20 mV and V G of 0.2 V vs. SCE is reduced upon raising the pH of the solution, where I D is the current between one electrode and the next, V D is the potential between the first and second electrode, and V G is the potential between the two electrodes and a saturated calomel reference electrode. I D at pH 1 is approximately 10 2 times greater than at pH 6.
Polyaniline is limited to use with solutions of pH less than 6 to preclude irreversible chemical changes that occur at the higher pH values. However, other pH-sensitive redox polymers may be used to fabricate microelectrode pH-sensors for other pH ranges.
Numerous uses in chemical systems are possible for such sensing devices. For example, such a device may be used to detect subtle changes in pH of aqueous solutions. Electrical signals generated by the device could be directly amplified and processed further.
EXAMPLE 4
A molecule-based diode 50, produced according to the present invention, is shown in FIG. 5. Microelectrodes 52 and 54 are each individually covered with polymers 56 and 58 having very different redox potentials. The current passes between the two heavily coated, connected microelectrodes 52 and 54 as a function of the threshold potential of the diode, which is dependent on the redox potentials of the polymers. Electrons only flow from microelectrode 52 to microelectrode 54 due to the large difference in the redox potentials of the two polymers 56 and 58. For example, for a polyviologen/polyvinylferrocene diode, charge will pass only when the negative lead of the applied potential is connected to the gold electrode 52 coated with polyviologen 56 and the positive lead is attached to the gold electrode 54 coated with polyvinylferrocene 58. This reaction is shown as: ##STR2##
As shown in FIG. 6, it is possible to electrochemically deposit electroactive polymers 60 on individual electrodes 62a-h in variable amounts. The electrodes 62e-h which are bridged by the polymer 60 are electrically connected: charge can pass from one microelectrode 62e to another microelectrode 62f-h via conduction mechanisms of the polymer 60. Connected electrodes are typically associated with coverages of approximately 10 -7 mol polymer/cm 2 electrode. Addressing one electrode oxidizes and reduces the polymer 60 over all of the electrodes 62e-h.
FIG. 7 shows the cyclic voltammetry of the polypyrrole modified array of FIG. 6 in CH 3 CN/0.1M [n-Bu 4 ]ClO 4 containing no added redox active species. The unfunctionalized electrodes 62a, 62b, and the electrode 62c, with a negligible amount of polypyrrole, lack the cyclic voltammetry signal characteristic of an electrode-confined polymer. Immediately adjacent to the non-derivatized electrodes 62a-c are electrodes 62d-h that show cyclic voltammograms characteristic of electrode-confined polypyrrole. The shape of the voltammogram is nearly the same as for a macroscopic gold electrode derivatized in the same manner. In addition, the potential of the oxidation and reduction peaks are as expected for the oxidation and reduction of polypyrrole.
Based on the integration of the charge passed upon cycling the derivatized microelectrodes 62 individually between the negative and positive limits, it can be seen that controlled amounts of polypyrrole 60 can be deposited on the electrodes 62. The same results, with the expected differences in the oxidation and reduction potentials, were shown using poly-N-methylpyrrole instead of polypyrrole.
FIGS. 8a and 8b show the spatial potential distributions across a polypyrrole array 70 where one (FIG. 8b) or two (FIG. 8a) of the electrodes is under active potential control. The entire array 70 was immersed in CH 3 CN/0.1M [n-Bu 4 ]ClO 4 and a biopotentiostat used to actively control the potential of one (FIG. 8b) or two (FIG. 8a) microelectrodes against a common reference and counter electrode in the electrolyte solution.
The potential of one microelectrode 72 in the five electrode array 70 was set at a negative potential of -1.0 V vs. SCE and the potential of another microelectrode 74 varied between 0.0 and 1.0 V vs. SCE.
As shown in FIG. 8a, the potentials of electrodes 76, 78, and 80 not under active potential control are nearly equal to the positive potential applied to electrode 74. Although a small potential drop of approximately 50 mV occurs over the 9 micron distance separating electrodes 74 and 80, the essential finding is that nearly all, up to 1.8 V, of the potential drop occurs across a narrow region immediately adjacent to electrode 72 under active potential control at -1.0 V vs. SCE. The result is consistent with the difference in conductivity between the reduced and oxidized state of the polypyrrole, of which the consequence is that the potential drop occurs across a very small fraction of length of the connecting polymer when one microelectrode is held at a potential where the polymer is reduced and insulating and another is held at a potential where the polymer is oxidized and conducting. This would not be an expected result for a polymer with only a moderate conductivity, such as those that exhibit redox conductivity where a linear change in concentration of redox centers across the thickness spanned by two electrodes at differing potentials would give a potential profile predicted by the Nernst equation.
FIG. 8b shows that when only one 82 of the microeletrodes is under active potential control in the positive region, all of the electrodes are at the same potential as would be expected when there is an electrical connection between them. When one of the microeletrodes is driven to a negative potential, it would be expected that all would ultimately follow. Upon reduction, however, the polymer becomes insulating and the rate of potential following can be expected to be slower.
As shown by the current vs. potential data in FIG. 9, polypyrrole connected-microelectrodes 90 behave in a diode-like fashion. Current vs. V applied curves are shown as a function of the potential, V set , at which one 92 of the electrodes is fixed relative to the SCE. The current measured is that passing between the two microelectrodes. The magnitude of the current passing through one microelectrode is identical to that passing through the other microelectrode but opposite in sign.
When V set is sufficiently positive, the current vs. V applied curve is linear over a wide range of V applied . The resistance of polypyrrole from the slope of such plots is about 10 3 ohms. Current densities exceeding 1 kA/cm 2 were observed. When V set is sufficiently negative, there is a broad range of the current vs. V applied curve where there is insignificant current. Therefore, as shown in FIG. 10a, a good diode characteristic can be obtained using polypyrrole coated, closely spaced microelectrodes. The onset of current closely corresponds to the situation where the V appl . results in the conversion of the polypyrrole from its reduced and insulating state to its oxidized and strongly conducting state.
As shown in FIG. 10b, results using poly-N-methylpyrrole in place of polypyrrole in the array shown in FIG. 9 were similar except that the value of V set necessary to obtain a current that is linear as V applied is varied is more positive than with polypyrrole. The resistance of the poly-N-methylpyrrole is 10 5 to 10 6 ohms. Both the higher resistance and the more positive potential necessary to obtain the conducting regime are consistent with the known differences between polypyrrole and poly-N-methylpyrrole.
EXAMPLE 5
A light emitting device 98 may also be made according to the process of the present invention. As shown in FIG. 11, light is emitted from a polymer 100 overlaying two gold microelectrodes 102 on a silicon dioxide-silicon substrate 104 when an electrical current is applied. In the depicted device, light characteristic of an excited Ru(bpy) 3 2+ species is emitted when a voltage of approximately 2.6 V is applied.
Polymers useful in a light emitting device according to the present invention can be polymerized from any monomers which are electrochemiluminescent, such as vinyl derivatives of rubrene or diphenyl anthracene.
EXAMPLE 6
A triode-like device was also constructed by electrochemical deposition and oxidation of a polyaniline film onto a microelectrode array consisting of eight gold electrodes, 0.1 micron thick, 4.4 microns wide, and 50 microns long, each individually addressable and separated from each other by 1.7 microns.
The magnitude of the current passing between electrically connected microelectrodes at a given applied potential depends on the electrochemical potential of the polyaniline. In an electrolyte of aqueous 0.5M NaHSO 4 , the current at a fixed applied potential is maximum at an electrochemical potential of +0.4 V vs. SCE and declines by a factor of greater than 10 6 upon reduction to a potential of +0.1 V vs. SCE or oxidation to +0.7 vs. SCE.
The polyaniline-functionalized microelectrodes were examined by cyclic voltammetry in 0.5M NaHSO 4 at pH 1 to assess coverage of the polymer and to determine whether the polymer coating two or more electrodes results in an electrical connection between them. Derivatization of the electrode can be controlled by adjusting the amount of polyaniniline by varying the amount of charge passed in the electrochemical polymerization. At one extreme, the amount of polyaniline can be small enough to derivatize the individual microelectrodes but not to electrically connect them. At the other extreme, polyaniline can be deposited in amounts sufficient to electrically connect all of the microelectrodes.
Both a separate, unconnected microelectrode and multiple, connected electrodes show the same cyclic voltammogram at 50 mV/s in 0.5M NaHSO 4 as does a single unconnected reference microelectrode at 50 mV/s in 0.5M NaHSO 4 . This is consistent with one electrode being capable of oxidizing all of the polyaniline present on a single microelectrode or on multiple connected microelectrodes. When adjacent derivatized microelectrodes are not connected, the sum of the areas under the cyclic voltammograms for the individual electrodes is the area found when the microelectrodes are externally connected together and driven as a single electrode. The thickness of polyaniline is not measured to be directly proportional to the integrated cyclic voltammetry wave as it is for surface-confined, viologen derived polymers. This lack of direct proportionality may be attributable to morophological changes in the polymer with increasing thickness.
As shown in FIG. 12 (inset), a triode-like device 110 was constructed by coating two adjacent gold microelectrodes 112, 114 with a five to 10 micron thick electrochemically deposited and polymerized film of polyaniline 116. Measurements were made by immersing the device 110 in aqueous 0.5M NaHSO 4 at 25° C. under an inert atmosphere of N 2 or Ar. Devices constructed in this manner exhibit fairly long term stability.
As shown by the cyclic voltammogram in FIG. 13 for the device 110, the connected pair of electrodes exhibits a nearly constant steady state current between the two microelectrodes for at least 6 hours when V D is 20 mV and V G is 0.3 V vs. SCE. In general, devices can be used for characterization for several days without significant deterioration.
The conductivity of polyaniline which is immersed in an electrolyte such as aqueous 0.5M NaHSO 4 depends on the electrochemical potential, which can be varied by varying V G . As shown in FIGS. 14a and 14b, the resistance of polyaniline depends on its electrochemical potential. The minimum resistance is at an electrochemical potential in the vicinity of +0.4 V vs. SCE. Changes in resistance in excess of 10 6 are routinely measured.
The minimum resistance for polyaniline is similar to that for polypyrrole connecting two microelectrodes spaced 1.4 microns apart, as shown in example 3. It is significantly different from polypyrrole, however, in that polyaniline is less conducting at potentials less than or greater than 0.4 V vs. SCE. The change in resistance of polyaniline is essentially reversible for potentials less than +0.6 V vs. SCE. Potentials significantly more positive than +0.6 V vs. SCE yield an increase in the ressistance of the poyaniline when the potential is again decreased to +0.4 V vs. SCE. The limit of positive applied potential is determined by O 2 evolution and limited durability of the polyaniline. The limit of negative applied potential is determined by the onset of H 2 evolution.
As shown in FIGS. 12a and 12b, the triode-like device 110 shows an increase and then a decrease in I D as V G is varied from negative to positive potentials, unlike conventional solid state devices which show an increase in I D and V G is varied until the I D ultimately levels off at a constant, V G -independent value. The charge passed in setting the gate to a potential where there is conductivity between the source 114 and drain 112 can be regarded as an input signal. For the device 110, the charge necessary to completely turn on the device is approximately 10 -6 C.
Transconductance. g m , is determined by the equation: ##EQU1##
Using the data in FIGS. 12a and 12b, the maximum value of g m for device 110 is approximately 20 millisiemens per millimeter of gate width, as determined from the rising part of the I D -V G curve as V G is moved to a potential more positive than approximately 0.1 mA/V.
By convention, gate length in Si/SiO 2 /metal field effect transistors (MOSFET) is the separation of source and drain. "Width" therefore corresponds to the long dimension of the device 110. Since the g m of device 110 is only about one-order of magnitude less than that for good MOSFET devices, the signal from the polyaniline-based device can be fed to conventional MOSFET in the form of voltage across a load resistance for further amplification.
Diode-like behavior can be obtained using device 110, as shown in FIG. 15, at V G values where the polyaniline is reduced and insulating. Current passes between the microelectrodes 112 and 114 when the "source" microelectrode 114 is oxidized. If the "drain " microelectrode 112 is moved to the negative of the source 114, current does not flow because the polyaniline remains insulating. Device 110 is not an exact analogue of a solid state diode because it is not a two-terminal device as is p-n junction or a metal/semiconductor Schottky barrier. The diode-like behavior of device 110 results from a chemical reaction of the polymer 116 at a particular potential that causes a change in conductivity of the polymer 116.
Persistent diode-like behavior is obtained by maintaining one microelectrode, the drain 112, at a negative potential at which it is insulating. Difficulties are encountered with degradation of the polyaniline when the potential of the microelectrode is held at a potential positive enough for the polyaniline to be insulating, +0.7 V vs. SCE, with the other microelectrode at a more negative potential.
Chemical-based devices depend on chemical reactions such as redox reactions which occur relatively slowly compared to the turn on/turn off speeds for solid state diodes and transistors. As shown in FIG. 16, device 110 can be turned on and off in less than one second. In FIG. 16, the value of I D is shown for a potential step of V G from -0.2 to +0.3 V vs. SCE then back to -0.2 V vs. SCE at V D of 0.18 V. By monitoring the rise and fall of I D of the potential steps, on to off times of less than 50 ms and slightly longer off to on times were shown.
The polyaniline-coated device 110 exemplifies the type of molecule-based devices that could be used as chemical sensors where the input signal to the device is a redox agent that can equilibrate with the polyaniline 116 to change the value of I D at a given value of V D . The specificity of the device stems from the fact that only those redox reagents that will bring the electrochemical potential of the polyaniline to a value that will allow current to pass will be detected. Further specificity arises from the failure of the polyaniline to react with a particular given redox reagent. For example, polyaniline does not equilibrate with the H + /H 2 redox couple. There is, however, rapid equilibration of polyaniline with one-electron outer-sphere redox reagents such as Ru(NH 3 ) 6 3+/2+ , E o ' approximately equal to -0.18 V vs. SCE which is close to the E o' of H + /H 2 at pH=1 of approximately -0.3 V vs. SCE.
Polyaniline also equilibrates with Fe(CN) 6 3-/4- . For example, immersion of the polyaniline-based device 110 into a solution of aqueous 0.5M NaHSO 4 containing the oxidant K 3 [Fe(CN) 6 ], E o' of [Fe(CN) 6 ] 3-/4- approximately equal to +0.2 V vs. SCE, turns the device "on". Immersion of the device into a solution of 0.5M NaHSO 4 containing Ru(NH 3 ) 6 2+ turns the device "off".
As depicted in FIG. 17, the change in resistance of the polyaniline with a change in electrochemical potential can be brought about by externally connecting the polyaniline-connected microelectrode array 120 to a macroscopic indicator electrode 122 that will respond to reagents 124 other than outer-sphere reagents. When the indicator electrode 122 is platinum, the microelectrode array 120 can be equilibrated with H + /H 2 since platinum equilibrates with H + /H 2 .
The device 130 in FIG. 18 is useful in characterizing the device of FIG. 17 since the potentiostat 132 and counter-electrode 134 can be used to quantitatively establish the amount of charge that is necessary to turn on the device 130. This device differs from the device 110 shown in FIG. 12A by the presence of an additional polymer-coated microelectrode and because the source and drain float.
It is also possible to chemically functionalize the polymer directly, as by the deposition of a metal such as palladium or a metal oxide onto the polyaniline connecting the microelectrodes. Palladium provides a mechanism for equilibrating the polymer with H 2 O/H 2 and O 2 /H 2 O.
The present invention may be embodied in other specific forms without departing from the spirit and scope thereof. These and other modifications of the invention will occur to those skilled in the art. Such other embodiments and modifications are intented to fall within the scope of the appended claims. | Several types of new microelectronic devices including diodes, transistors, sensors, surface energy storage elements, and light-emitting devices are disclosed. The properties of these devices can be controlled by molecular-level changes in electroactive polymer components. These polymer components are formed from electrochemically polymerizable material whose physical properties change in response to chemical changes, and can be used to bring about an electrical connection between two or more closely spaced microelectrodes. Examples of such materials include polypyrrole, polyaniline, and polythiophene, which respond to changes in redox potential. Each electrode can be individually addressed and characterized electrochemically by controlling the amount and chemical composition of the functionalizing polymer. Sensitivity of the devices may be increased by decreasing separations between electrodes as well as altering the chemical environment of the electrode-confined polymer. These very small, specific, sensitive devices provide means for interfacing electrical and chemical systems while consuming very little power. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application Ser. No. 61/930,057, filed Jan. 22, 2014, which is hereby incorporated by reference in its entirety.
FIELD OF THE DISCLOSURE
This disclosure relates to bicycles that are transformable into a cart, wheelbarrow, or the like. In particular, the disclosure relates to a transformable bicycle suitable for use in outdoor activities such as hunting, camping, or the like.
BACKGROUND
Transformable bicycles are known, however, they are typically transformable, or foldable, for convenience of transporting or storing, and, thus, are sized to be smaller, or less rugged than typical bicycles. Likewise, some transformable bicycles have customized or specialized frames or other components in order to be compactly folded or otherwise transformed.
The smaller components (e.g., wheels) or specialized frames are typically due to the compromise between compactness when folded and comfort when ridden as a bicycle. Typically, for most transformable bicycles it is more important that the bicycle fold down to a smaller size for ease of transport (e.g., storing in an automobile trunk or carried onto public transportation) than it is for optimal riding comfort or ease. Such transformable bicycles may be suitable for commuting, light shopping (e.g., smaller or a few packages), or the like. However, small-wheeled or custom framed transformable bicycles are not suitable for use in outdoor or other rougher riding environments. Furthermore, existing transformable bicycles are not suitable for carrying heavy or awkward loads when transformed. Other drawbacks and disadvantages of existing transformable bicycles also may exist.
Thus, there exists a need for a durable, full-sized, transformable bicycle that is capable of being comfortably ridden in outdoor or other rougher riding environments and that is capable of being transformed into a cart or the like capable of carrying heavy or awkward loads when transformed. Other needs are also met by the disclosed embodiments.
SUMMARY
Accordingly, disclosed embodiments include a transformable bicycle having a front wheel, a back wheel, a frame having at least one pivot point, at least one brake, a front rack located substantially over the front wheel, a back rack located substantially over the back wheel, and at least one cart handle extension connected to the frame. In some embodiments, pivoting the frame about the at least one pivot point enables the front wheel to be positioned substantially parallel and substantially coaxial with the back wheel.
In some embodiments, the least one of the front rack and the back rack further have a rack lock. In some embodiments, when the frame is pivoted about the at least one pivot point the rack lock connects the front rack to the back rack.
In some embodiments, at least one of the front rack and the back rack further have at least one foldable portion. In further embodiments, the at least one cart handle extension is adjustable. In still further embodiments, the at least one cart handle extension is adjustable in at least one of a rotational aspect and a length.
In some embodiments, the transformable bicycle has at least one handlebar and the at least one brake is mounted on the at least one handlebar. In some embodiments, the at least one handlebar is selectively removable and mountable in the at least one cart handle extension.
Some disclosed embodiments include a bicycle, convertible into a cart, having a front wheel, a rear wheel, a frame having at least one pivot point, further having a socket, wherein the at least one pivot point pivots at least a portion of the frame and positions the front wheel next to and substantially parallel and substantially coaxial with the rear wheel, a right handlebar, a left handlebar, a rack for carrying cargo, at least one brake mounted on either the right or left handlebar, a cart handle extension comprising a socket, and wherein at least one of the right handlebar and the left handlebar are removable and mountable in either the at least one pivot point socket or the cart handle extension socket to form at least one cart handle.
In some embodiments, when the frame is pivoted and the front wheel is positioned next to the rear wheel, the rack is positioned substantially over both the front wheel and the rear wheel, and the at least one cart handle is positioned behind the rack. In some embodiments, the at least one brake mounted on at least one of the left handlebar or the right handlebar is movable along with at least one of the left handlebar or the right handlebar when mounted as at least one cart handle.
In some embodiments, the rack further comprises at least one foldable portion. In further embodiments, at least one of the cart handles is an adjustable handle. In still further embodiments, the adjustable handle is adjustable in length. Other features and advantages of the disclosed embodiments also exist.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of embodiments of the disclosed transformable bicycle in bicycle configuration.
FIG. 2 is a front view of the transformable bicycle in cart configuration in accordance with some disclosed embodiments.
FIG. 3 is a perspective view of a foldable rack in accordance with some disclosed embodiments.
FIG. 4 is a perspective view of the transformable bicycle in cart configuration loaded with cargo.
FIG. 5 is a perspective view of the transformable bicycle in bicycle configuration with the front rack unfolded to carry cargo.
While the disclosure is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the disclosure is not intended to be limited to the particular forms disclosed. Rather, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION
FIG. 1 is a side view of embodiments of the disclosed transformable bicycle 10 in bicycle configuration. As shown, embodiments of transformable bicycle 10 may comprise the typical components for a full-sized bicycle suitable for riding outdoors over rough terrain (i.e., a so-called “mountain bike,” or the like). As shown, the transformable bicycle 10 may comprise wheels 12 , a frame 14 , handlebars (left 16 , right 17 ), pedals 18 , a chain 20 , one or more gears 22 , a seat 24 , and brakes 26 . As also shown, embodiments of the transformable bicycle 10 may also comprise a front rack 28 , mounted over the front wheel 12 , and a back rack 30 , mounted over the back, or rear, wheel 30 . Additional features of front rack 28 and back rack 30 are discussed below.
Embodiments of the transformable bicycle 10 also comprise a left cart handle extension 50 and a right cart handle 34 . In some embodiments, when in the bicycle configuration, the left handlebar 16 and right handle bar 17 are substantially perpendicular with the frame 14 as shown in FIG. 1 to permit normal riding of the transformable bicycle 10 . Additional features enabling the transformation of handlebars ( 16 . 17 ) into cart handles ( 32 , 34 ) are as discussed below.
FIG. 2 is a rear view of the transformable bicycle 10 in cart configuration in accordance with some disclosed embodiments. As shown, embodiments of transformable bicycle 10 may comprise a frame 14 with two pivot points ( 36 , 38 ). First pivot point 36 may be located at or near the front of frame 14 (e.g., under handlebars 16 , 17 ) and second pivot point 38 may be located at or near the rear of the frame 14 (e.g., under seat 24 ). Location of the pivot points ( 36 , 38 ) in such a manner enables the front and rear wheels 12 to be positioned substantially parallel, and substantially coaxial, to one another as shown in FIG. 2 . As also shown, embodiments of transformable bicycle 10 may also comprise a stand, such as kick stand 40 , that enables the transformable bicycle 10 to be stood upright in either bicycle or cart configuration.
For some embodiments first and second pivot points ( 36 , 38 ) may be held in place by implementation of a suitable locking device. For example, a locking pin (not shown) may be selectively inserted through corresponding holes in frame 14 to selectively secure the pivot points ( 36 , 38 ) in the desired position. In some embodiments it is preferable that the pivoting and locking can be accomplished without the use of any tools or other implements. Other locking devices are also possible.
As also illustrated in FIG. 2 , for some embodiments, when the frame 14 is pivoted from bicycle to cart configuration, handle bars ( 16 , 17 ) may be removed from the head clamp 49 and inserted into appropriate receptors to form cart handles ( 32 , 34 ). For example, left handlebar 16 may be inserted into left cart handle extension 50 to form left cart handle 32 and right handlebar 17 may be inserted into an appropriate socket on the second pivot point 38 to form right cart handle 34 . In some embodiments, left and right handlebars ( 16 , 17 ) may be locked into place in the respective receptors through a pin-and-hole arrangement, threading, a compression fit lock, or the like. Preferably, the removal, rearrangement, and locking of the handlebars ( 16 , 17 ) into place as cart handles ( 32 , 34 ) may be accomplished by hand without the need for other tools. Other embodiments may allow for the pivoting and locking of both left and right cart handles ( 32 , 34 ) in order to allow for wider or narrower handle positions as desired. In some embodiments it is preferable that the pivoting and locking can be accomplished without the use of any tools or other implements.
As also illustrated in FIGS. 2 and 3 embodiments of transformable bicycle 10 may comprise foldable front ( 28 ) and back ( 30 ) racks. Some embodiments may comprise one or more foldable portions for each rack ( 28 , 30 ). For example, front rack 28 may have a single foldable portion 282 and back rack 30 may have two foldable portions 302 , 304 . Of course, other configurations for the foldable portions are also possible. As shown, front rack 28 and back rack 30 may comprise a suitable number of hinges 306 to enable the foldable portions (e.g., 282 , 302 , 304 ) to fold out to a substantially flat position. As shown in FIG. 3 , hinges 306 also enable the racks (e.g., back rack 30 ) to be folded into a smaller configuration that may be preferable in some circumstances (e.g., when riding in bicycle configuration).
As shown in FIG. 3 , front rack 28 and back rack 30 substantially align when in cart configuration and, for some embodiments, may be locked into position by a suitable rack lock 42 . In some embodiments, rack lock 42 may comprise a pin and through-hole arrangement, however, other rack locks 42 , such as hooks, clasps, or the like, are also possible. In embodiments where front rack 28 and back rack 30 are extended and locked into position, they provide a relatively large and sturdy platform on which relatively heavy or awkward objects can be loaded and carried.
For example, FIG. 4 is a perspective view of the transformable bicycle 10 in cart configuration loaded with a cargo 44 . In the exemplary embodiment shown in FIG. 4 , the cargo may comprise a full sized hay bale (e.g., approximately 16″×24″×48″).
Likewise, one or more of the racks ( 28 , 30 ) may be unfolded while in bicycle configuration as well in order to facilitate the transport of larger cargo 44 while riding. For example, FIG. 5 is a side view of the transformable bicycle 10 in bicycle configuration with front rack 28 unfolded to carry cargo 44 comprising a chain saw and back rack partially unfolded to carry cargo 44 comprising a tool box or fuel canister. In such a manner the transformable bicycle 10 may be ridden in bicycle mode out to a remote forest trail, or the like, while transporting the appropriate tools to cut trees and then converted to cart configuration to transport the cut logs back to a convenient location. Another potential application of the disclosed transformable bicycle is to ride the bicycle in bicycle configuration out to a relatively remote hunting spot. Then, after harvesting a game animal, put the transformable bicycle into cart configuration and use the locked racks ( 28 , 30 ) to transport the cargo 44 (i.e., the animal carcass) to a convenient location. Of course, other applications are also possible.
FIG. 4 also illustrates other features of some embodiments of transformable bicycle 10 . As shown, for some embodiments, it may be desirable that brakes 26 and associated cables (cables and other brake components not shown for clarity) may be relocated along with the handlebars ( 16 , 17 ) (e.g., for use when in bicycle configuration) to be usable with left cart handle 32 and right cart handle 34 to enable braking of the wheels 12 during cart configuration operations. Other movable brake 26 schemes are also possible.
In addition, for some embodiments left cart handle 32 and right cart handle 34 may be further adjustable for additional user comfort and ease by including grips 46 and a handle adjustment portion 48 that enables the handles 32 , 34 , to be rotated, extended, or contracted according to user preference. For example, adjustment portion 48 may comprise a pin-and-hole arrangement to allow the positioning of the handles 32 , 34 , or adjustment portion may comprise threaded portions, hand-adjustable compression fittings, or the like.
Although various embodiments have been shown and described, the present disclosure is not so limited and will be understood to include all such modifications and variations are would be apparent to one skilled in the art. | A durable, full-sized, transformable bicycle that is capable of being comfortably ridden in outdoor or other rougher riding environments and that is capable of being transformed into a cart or the like capable of carrying heavy or awkward loads when transformed. | 1 |
This application is a continuation of application Ser. No. 07/213,901, filed June 30, 1988 now abandoned.
BACKGROUND OF THE INVENTION:
1. Field of the Invention
The present invention relates generally to an apparatus and process for transferring liquids, especially liquids, such as molten sulfur, which are difficult to handle, from one location or container to another by the use of a pressurized gas.
2. Background Discussion
Sulfur is the fifteenth most common terrestrial element and is of great commercial importance. According to published statistics, about 9.8 million tons of sulfur were produced in the United States in 1986, about 49 percent of which was used--principally in the form of sulfuric acid--for industrial purposes, including the production of petrochemicals, plastics and fibers. Another 25 percent of the produced sulfur was used for inorganics and pigments, and about 12 percent for non-chemical purposes, such as plating. The remaining 14 percent or so of the produced sulfur was used, indirectly or directly, in agriculture--about 9 percent as sulfuric acid for the production of phosphate fertilizers and the remaining 5 percent for application to crops and the like.
Unlike most elements, sulfur is produced by both "voluntary" and "involuntary" means. In "voluntary" production, sulfur is intentionally mined and produced from naturally-occurring ores or deposits, with such production being entirely discretionary on the part of the sulfur producers. By contrast, in "involuntary" production, sulfur is produced as a necessary by-product of other processes, or from the manufacture of other products. Consequently, involuntary sulfur production depends upon the market for the other processes or products and not upon the demand for sulfur.
With regard to the involuntary production of sulfur, large quantities of elemental sulfur are, for example, obtained from unwanted hydrogen sulfide and/or sulfur removed from natural gas, crude oil, and geothermal fluids during the production, processing, or use of these fluids. Natural gas, for example, typically contains between about 15 and 30 percent of hydrogen sulfide which must be removed, to meet pollution standards, before or during use of the gas. Moreover, in addition to usually containing some hydrogen sulfide, crude oils typically contain between about 0.1 and 2.8 percent of elemental sulfur, with some "sour" oils having over a 3 percent sulfur content; most of this sulfur must be removed from the crude oil during its refining.
More than half the sulfur presently produced in the United States is produced involuntarily. For example, of the approximately 9.8 million tons of sulfur produced in the United States in 1986, only about 4.0 million tons were "voluntarily" produced, mainly by the Frash process. Of the remaining 5.8 million tons of "involuntary" sulfur, about 2.24 million tons were reportedly produced as a by-product of cleaning natural gas.
This high percentage of involuntarily-produced sulfur can and does cause substantial upsets in the sulfur market. In the early 1970s, for example, the Mideast oil embargoes forced a greatly increased reliance on higher sulfur-content, "sour" crude oils from other regions of the world. As a consequence, involuntary sulfur producers (principally in the oil and gas industry) accumulated huge surpluses of sulfur, thereby causing a worldwide sulfur surplus and a substantial decrease in the market value of sulfur. The curtailing of voluntary sulfur production and the resumed usage of lower sulfur-content oil has since reduced these huge sulfur surpluses of the early 1970s; nevertheless, sulfur surpluses still, from time to time, occur. More recent surpluses of sulfur have, for example, been caused by such factors as the diminished demand for sulfur for producing phosphate fertilizers (due to improved crop strains and the over-productions of food in many countries) and the still-increasing use of sour oil from Texas, Mexico, and Venezuela.
Mainly because of such sulfur surpluses, new and/or expanded uses for sulfur have been sought in order to stabilize the sulfur market. Most of the new or proposed new, uses for sulfur are for structural materials, principally: (i) sulfur-asphalt compositions for road building, (ii) rigid sulfur foams for thermal insulation, and (iii) sulfur-based concrete for special applications in which the properties of conventional, portland cement-based concretes are inadequate.
Regarding the combining of sulfur with asphalt--with which the present invention is indirectly concerned--it has been well known for over a century that sulfur can improve the properties of asphalt compositions. For example, the addition of sulfur to asphalt can result in the increased stability of asphalt pavements (macadam), and in reduced pavement rutting, washboarding, and deflections. However, only in recent years have the necessary techniques been developed to the extent that sulfur and asphalt can be combined in a practical manner.
Sulfur can be incorporated into asphalt for paving in either of two principal ways, each of which has a different purpose. One such way is to incorporate molten sulfur in a hot mix; the other way is to produce an asphalt/sulfur emulsion. By adding about 13 percent of sulfur in the hot mix asphalt process, most or all of the generally costly (and increasingly scarce) rock aggregate, which would normally be used in the paving material, can be replaced with much less costly, and more readily available, sand. Although the added sulfur increases the fluidity of the hot mix, when the mix cools the sulfur solidifies and contributes to the mechanical stability of the mixture.
In the sulfur/asphalt emulsion process, molten sulfur replaces some of the asphalt oil binder, which is usually more costly than sulfur. Such so-called "sulfur-extended asphalts" typically contain 30 to 50 percent of sulfur which may be emulsified into the asphalt by a special mixer.
Other processes for using sulfur as a replacement for asphalt in a plasticized sulfur composition have reportedly been developed for the U.S. Federal Highway Administration and tested by the U.S. Bureau of Mines. These plasticized sulfur compositions contain substantial amounts of such plasticizers as dicyclopentadiene. However, the high cost of the plasticizers is presently impeding significant development of the material.
Along with the interest of the sulfur industry in developing new uses and markets for sulfur, a Strategic Highway Research Program (SHRP) has recently been established in the United States to provide carefully targeted research toward improving highway materials and pavement performance so as to preserve the trillion dollar investment in United States highways. One specially targeted area of research for the $150 million, 5-year study program by SHRP is asphalt, since of the slightly over 2 million miles of paved highways in the United States, nearly 1.9 million miles consist, at least in part, of asphaltic materials. In this regard, about 30-35 million tons of asphalt paving material are reportedly used each year just in the State of California.
One of the problems associated with the use of molten sulfur for such purposes as compounding asphalt paving materials is that sulfur has a fairly high melting point of 115.2° C. (about 240° F.). Relatively costly systems are, therefore, presently required for storing and transferring molten sulfur, which is commonly delivered to a road-building site in liquid form by tank trucks typically containing about 23 to 24 tons (about 3200 gallons) of sulfur. Moreover, such molten sulfur handling and transferring systems are required to be mobile to the extent they can be advanced along a roadway with other equipment as the sulfur/asphalt pavement composition is applied. To keep the sulfur in its molten state, such systems typically require a steam-jacketed tank for storing the molten sulfur, a boiler for generating steam for the steam jacket, and a pump and piping for continuously recirculating molten sulfur through the discharge pipe used to deliver the sulfur to apparatus in which the sulfur is to be mixed when needed. Some type of molten sulfur metering or weighing equipment is additionally required so that the proper amount of molten sulfur can be mixed with asphalt and aggregate or sand to make the sulfur/asphalt paving material.
The relatively high cost of such molten sulfur handling and transfer systems--the estimated cost for each such system is between about $50,000 and about $100,000--tends to make it difficult to generate great interest in the use by paving contractors of sulfur as an asphalt pavement component, particularly since there is not presently a large surplus of sulfur and its cost is not particularly low.
SUMMARY OF THE INVENTION
To eliminate the need for large, costly, on-site molten sulfur storage and handling equipment, and to thereby encourage the use of sulfur in the asphalt paving industry, the present inventors have developed a relatively compact, inexpensive--yet very efficient and effective--apparatus. The present apparatus enables molten sulfur to be rapidly transferred from a delivery vehicle, in small, discrete "slugs," to an existing asphalt mixing apparatus (pug mill) used for blending asphalt oil and aggregate into a paving material.
There is accordingly provided, in accordance with the present invention, an apparatus for transferring a liquid, particularly a liquid, such as molten sulfur, which is difficult to handle, from a liquid supply to another location. The apparatus comprises a transfer vessel or tank having a liquid inlet and outlet, the inlet being connected to the liquid supply and adapted for receiving a gravity flow of liquid therefrom. Means, preferably a check valve, are provided for permitting the liquid to flow from the liquid supply into the transfer vessel while blocking the flow of the liquid from the transfer vessel back to the liquid supply.
The apparatus further includes means, preferably comprising an air compressor and a pressurized air conduit, for providing a flow of pressurized gas to the transfer vessel to force liquid contained therein out through the vessel outlet and to the other location. Preferably included are means for controlling the flow of pressurized gas to the transfer vessel. Also in the preferred embodiment, the pressurized air conduit is adapted to have a portion thereof extend above the level of liquid in the liquid supply to prevent the liquid from the supply and/or the transfer vessel from flowing into the compressor.
A corresponding process is provided for transferring a liquid, preferably a difficult-to-handle liquid, and most preferably molten sulfur, from a supply to another location. The most preferred process comprises the steps of: (i) connecting an inlet of a transfer vessel to a supply of molten sulfur and an outlet of the transfer vessel to a location other than that of the supply, (b) flowing, under gravity, molten sulfur from the supply into the transfer vessel, and (iii) pressurizing, with a pressurized gas, the transfer vessel so as to force molten sulfur contained in the vessel out through an outlet and to the other location. The process includes the step of preventing the flow of molten sulfur from the inlet of the transfer vessel back to the supply of molten sulfur and from the supply and the transfer vessel to the source of pressurized gas.
It is preferred that the volume of the transfer vessel be substantially smaller than the volume of the molten sulfur supply, the process then including repeating, in sequence, the steps of flowing molten sulfur from the molten sulfur supply into the transfer vessel and of pressurizing the transfer vessel to transfer the molten sulfur in the vessel to the other location, thereby causing molten sulfur to be transferred from the supply to the other location in a series of small, discrete slugs, each of which preferably has the same volume.
BRIEF DESCRIPTION OF THE DRAWING
The present invention can be more readily understood from the following detailed description when taken in conjunction with the accompanying drawing in which there is depicted (in schematic form) a volumetric transfer apparatus, in accordance with the present invention, for transferring molten sulfur or the like from a supply (for example a delivery tank truck) to a point of use (for example an asphalt-mixing pug mill). In the drawing, a molten sulfur transfer tank, which comprises part of the apparatus, is shown partially cut away so that a flow check valve disposed in the tank can be seen.
DESCRIPTION OF THE PREFERRED EMBODIMENT
There is schematically depicted in the drawing a volumetric liquid transfer apparatus 10, according to the present invention. By way of illustrative example, volumetric liquid transfer apparatus 10 is connected for incrementally transferring molten sulfur, in specific, known, relatively small amounts or slugs, from a delivery tank truck (or other delivery vehicle) 12 to a pug mill 14 wherein, as described below, the molten sulfur is combined with asphalt oil and aggregate to compound batches of a material suitable for paving roads, parking lots, and the like. Located beneath pug mill 14 is a hopper 16 into which the pug mill discharges batches of mixed sulfur/asphalt/aggregate paving material 17. From hopper 16, paving material 17 is discharged onto a conveyor 18 which delivers the paving material to a point of use or to a storage area (not shown). Alternatively, conveyor 18 may be eliminated to enable hopper 16 to discharge mixed sulfur/asphalt paving material 17 into trucks (not shown) for delivery to a paving site.
It is, however, to be appreciated that apparatus 10 of the present invention is not limited to the transfer of molten sulfur between delivery tank truck 12 and pug mill 14, nor is the present invention even limited to the transfer of molten sulfur. Thus, the apparatus of the present invention may be advantageously used for the measured (volumetric) transfer of any type of liquid, but especially those liquids which are difficult to handle--such as liquids having high viscosities or high melting points, or which are highly corrosive--because no complicated parts, such as flow meters and pumps, having continually moving parts, are needed. Another important advantage of apparatus 10 is that, as described below, the apparatus is self cleaning after use, making it additionally advantageous to use with difficult-to-handle liquids.
Shown comprising transfer apparatus 10 are a relatively small volume transfer vessel or tank 20 (which is positioned at a lower elevation than the liquid discharge point of tank truck 12) and an air compressor or other source (such as a pressure tank) of pressurized air (or gas) 22, the latter preferably having a pressure relief conduit 23. Connected in liquid flow series between a fitting 24 at the bottom of tank truck 12 and the top of vessel 20 are a manual shutoff valve 26 and a one-way, check valve 28 which permits the flow of molten sulfur from the tank truck into the vessel, but not from the vessel back into the tank truck. As will be apparent from the following description, check valve 28, which may be of a simple, flapper-type, as is known in the art, has the only moving part in the molten sulfur flow path through apparatus 10.
Shutoff valve 26 is ordinarily an existing part of tank truck 12 (and is not, therefore, usually part of transfer apparatus 10), being mounted directly to fitting 24, or a short conduit 30 extending downwardly therefrom. Liquid transfer apparatus 10 includes a fitting 31, upstream of check valve 28, which enables liquid transfer apparatus 10 to be connected, through shutoff valve 26, to tank truck 12. A conduit 32 upstream of check valve 28 is connected between connection fitting 31 and a liquid inlet 33 of vessel 20. Preferably, as shown in the drawing, check valve 28 is disposed within transfer vessel 20, at inlet 33, so that the heat of molten sulfur in the vessel keeps the check valve from freezing up with solidified sulfur. Alternatively, although less advantageously, check valve 28 could be installed upstream of vessel 20 in conduit 32.
Connected between a liquid outlet 34 of transfer vessel 20 and pug mill 14 is a molten sulfur transfer conduit 36, exposed regions of which are preferably thermally insulated. Transfer conduit 36 includes a standpipe portion 38 which extends downwardly through vessel outlet 34 nearly to the bottom of vessel 20.
A pressurized air conduit 40 is connected between compressor 22 and a gas inlet 41 at the top of transfer vessel 20 to enable pressurization of the vessel with air from the compressor. Preferably (as depicted in the drawing) compressed air conduit 40 extends to an elevation above the top of tank truck 12 so that molten sulfur is prevented from flowing from the tank truck (or from vessel 20) into compressor 22, thereby eliminating the need for a check valve in the compressed air conduit. However, if desired, a check valve (similar to check valve 28) can additionally, or as an alternative to routing compressed air conduit 40 above the top of tank truck 12, be installed in the compressed air conduit.
An electrically controlled shutoff valve 42 (which may be electrically or pneumatically actuated) is installed in air conduit 40, such valve being controlled through an electrical conduit 44 by a control unit 45. Although control unit 45 preferably comprises a known type of timer/sequencer 46, it may alternatively (or additionally) comprise a simple, manually-operated, electrical on/off switch 47 (shown in phantom lines in the drawing).
Timer/sequencer 46 is connected for automatically cycling valve 42 on and off in accordance with a pre-established timing sequence. Such a timing sequence is determined by such factors as: (i) the amount of molten sulfur to be combined with the asphalt oil and aggregate in pug mill 14 for each batch of paving material 17 to be mixed therein, (ii) the volume of transfer vessel 20, (iii) the length of time required to gravity fill the transfer vessel with molten sulfur from tank truck 12, (iv) the length of time required to transfer each slug of molten sulfur from the transfer vessel to the pug mill, (v) the mixing time in the pug mill of the molten sulfur, asphalt oil, and aggregate for each batch of paving material 17, and (vi) the time delay (if any) between the discharge of one batch of paving material from the pug mill and the receiving of molten sulfur into the pug mill for the next batch. Control unit 46 may also be connected to compressor 22, by an electrical conduit 48, for turning the compressor on and off at the start and end of the entire pavement mixing operation.
The gravity draining of molten sulfur from transfer vessel 20 (if necessary, for example, in the event compressor 22 fails to operate or valve 42 fails to open as required after the vessel has been filled with molten sulfur) is enabled by a drain valve 50 which is connected to the bottom of the vessel by a conduit 52.
For convenience in moving apparatus 10 from place to place, transfer vessel 20 and compressor 22 may be mounted on a skid or pallet 54 (shown in phantom lines in the drawing).
OPERATION OF TRANSFER APPARATUS 10
After tank truck 12 arrives at a site where sulfur/asphalt oil/aggregate paving material 17 is to be mixed (and with tank truck shutoff valve 26, tank drain valve 50, and compressed air valve 42 all closed) transfer apparatus 10 is connected to the tank truck shutoff valve by connector 31. Compressor 22 is started and air pressure is permitted to build up in the compressor. Normally thereafter, compressor 22 is kept running, with the compressed air being vented, for example, through pressure relief conduit 23, when valve 42 in compressed air conduit 40 to transfer vessel 20 is closed.
As initial, measured amounts of aggregate and asphalt oil are being introduced into pug mill 14 in a conventional manner, valve 26 at the bottom of tank truck 12 is opened, thereby permitting molten sulfur to flow from tank truck 12 into transfer vessel 20 through check valve 28. As above-mentioned, transfer vessel 20 is physically positioned below the level of tank truck 12 to enable the gravity flow of molten sulfur from the tank truck into the transfer vessel.
After transfer vessel 20 has been filled with molten sulfur in this manner, and when molten sulfur is required by pug mill 14, compressed air valve 42 is opened, by timer/sequencer 46 of control unit 45, thereby supplying compressed air, through conduit 40, to the vessel. As compressed air is supplied to transfer vessel 20, check valve 28 between the vessel and tank truck 12 is forced closed. Check valve 28 thus prevents (without the need to close shutoff valve 26) the flow of molten sulfur back into the tank truck and enables transfer vessel 20 to be pressurized and the molten sulfur held therein to be forced, by the compressed air, from the transfer vessel, through conduit 36, into pug mill 14.
After the length of time required for compressed air from conduit 40 to force all the molten sulfur from transfer vessel 20 into pug mill 14, compressed air valve 42 is closed by timer/sequencer 46. Transfer vessel 20 then depressurizes (through conduit 36), thereby permitting check valve 28 to automatically reopen. Transfer vessel 20 then refills, through check valve 28 and shutoff valve 26, with molten sulfur from tank truck 12.
In the alternative, if only manual on-off switch 47 is provided in control unit 45, such switch is manually actuated so as to close valve 42 in compressed air conduit 40 either after a measured time interval which is sufficient to transfer the molten sulfur from vessel 20 into pug mill 14 or when it has otherwise been determined that all the molten sulfur has been forced by the compressed air from the vessel into pug mill 14. Such complete emptying of transfer tank can, for example, usually be detected by the sound of compressed air flowing through outlet conduit 36.
Pug mill 14 typically batch-mixes the aggregate, asphalt oil, and molten sulfur supplied to it, transfer vessel 20 being preferably, but not necessarily, constructed to hold the total amount of molten sulfur required for one such batch. If transfer vessel 20 holds less than the amount of molten sulfur required for mixing a batch of paving material 17 (for example, if all the required molten sulfur is not to be introduced into pug mill 14 in a single slug), more than one of the above-described fill and transfer cycle is required for each batch of paving material 17. Assuming that all factors (such as those listed above) determining the operating schedule of apparatus 10 are known in advance, timer-sequencer 46 of control unit 45 is preferably programmed so that the opening and closing of compressed air valve 42 is performed in a manner automatically transferring the required amounts of molten sulfur from tank truck 12 to pug mill 14 at the required times.
In the event, however, that automatic timer/sequencer 46 is not provided in control unit 45, manual switch 47 controlling compressed air valve 42 can be actuated to achieve substantially the same results described above, but usually in a less convenient manner. However, if pug mill 14 is not operated in accordance with a preestablished schedule, manual operation of control unit 45 by manual switch 47 may be necessary, such switch thereby providing an optional, manual mode of operation.
From the foregoing description it is evident that the molten sulfur is transferred from vessel 20 into pug mill 14 in relatively small (compared to the volume of tank truck 12), discrete amounts or slugs, the size of each of which is determined by the volume of the transfer vessel. It is further evident that the cyclic sequence of filling transfer vessel 20 with molten sulfur from tank truck 12 and then emptying the molten sulfur from the transfer vessel into pug mill 14 is enabled solely by the respective closing and opening of valve 42 in compressed air conduit 40 (assuming, of course, that shutoff valve 26 at the bottom of the tank truck is left open). The only moving parts in apparatus 10 which are in the molten sulfur flow path are those in check valve 28.
An important advantage of apparatus 10 is that after the last slug of molten sulfur required for any pavement mixing operation has been forced (by the compressed air) from vessel 20, through molten sulfur conduit 36, to pug mill 14, both the vessel (including check valve 28) and conduit 36 are (or can readily be) swept free of the molten sulfur by the compressed air used to transfer the molten sulfur (shutoff valve 26 being closed to prevent any more molten sulfur flowing from tank truck 12 into the vessel). Consequently, apparatus 10 can be removed from operation without the necessity for draining molten sulfur therefrom or for having to heat the apparatus, or any part thereof, to a temperature above the sulfur solidification point. Should any small amount of sulfur happen to solidify in check valve 28, the next time apparatus 10 is connected to a sulfur tank truck 12 and valve 26 is opened, the heat of the molten sulfur from the truck will rapidly melt any sulfur solidified in the check valve.
A corresponding process is provided for transferring a liquid, such as molten sulfur, from a supply, such as tank truck 12, to another location, such as pug mill 14.
EXAMPLE
By way of a specific example, with no limitations being thereby intended or implied, a typical tank truck 12 holds about 3200 gallons (48,000 pounds, at about 15 pounds per gallon) of molten sulfur. A typical pug mill 14 batch-mixes about 5 tons of paving material 17 (in proportions of about 9500 pounds of aggregate, about 283 pounds of asphalt oil, and about 206 pounds of molten sulfur) in about 45-50 seconds. To provide a 206 pound slug of molten sulfur, transfer vessel 20 is about 12 inches in diameter and about 30-36 inches high, thereby having a capacity of about 14 gallons.
Shut-off valve 26 at the bottom of tank truck 12 and check valve 28 at the inlet to transfer vessel 20 are 3-inch valves. The molten sulfur discharge rate from the tank truck into the transfer vessel is typically about 200-300 gallons per minute (depending upon the sulfur head in the tank truck). The average fill time of transfer vessel 20 is thus typically less than about 5 seconds.
Compressor 22 is selected to have an output of about 10-20 cubic feet per minute at a pressure of somewhat less than 100 psig. Compressed air conduit 40 is a 2-inch pipe or flexible hose, and conduit 36, through which molten sulfur is discharged from transfer tank 20, is a 3-inch, insulated pipe. A typical time in which transfer tank 20 is emptied by compressed air from compressor 22 is about 10 seconds.
Assuming: (i) an asphalt material batch mixing time in pug mill 14 of 45 seconds, (ii) the continuous (that is, batch-after-batch) production of mixed batches of paving material 17 from the pug mill, and (iii) an emptying time of 10 seconds for transfer tank 20, timer-sequencer 46 of control unit 45 is set to automatically open valve 42 in compressed air conduit 40 every 45 seconds for about 10 seconds, so as to automatically provide a 206 pound slug of molten sulfur from vessel 20 to the pug mill every 45 seconds.
Although there has been described above a volumetric transfer apparatus for liquids, and particularly such difficult-to-handle liquids as molten sulfur, in accordance with the present invention for purposes of illustrating the manner in which the invention can be used to advantage, it is to be understood that the invention is not limited thereto. Accordingly, any and all variations and modifications which may occur to one skilled in the art are to be considered to fall within the scope and spirit of the invention as defined by the appended claims. | Apparatus is provided for transferring a liquid, particularly liquids, such as molten sulfur which are difficult to handle, from a liquid supply, such as a molten sulfur tank truck, to another location, such as a pug mill in which a sulfur/asphalt pavement material is blended. The apparatus comprises a relatively small transfer vessel, which is connected, through a shutoff valve, to the liquid for receiving a gravity flow of liquid therefrom, and an air compressor for pressurizing the transfer vessel through a pressurized air conduit. A check valve installed in the transfer vessel adjacent the liquid inlet of the vessel prevents the trasfer of liquid from the vessel back into the supply when the vessel is pressurized. An electrically-controlled valve in the pressurized air conduit enables an associated control unit to control the flow of pressurized air into the vessel. When the vessel is connected to the source and is unpressurized, liquid flows from the source into the vessel through the check valve; pressurization of the vessel by the compressor then closes the check valve and forces the liquid contained in the vessel out of the vessel and to the other location. An elevated loop in the pressurized air conduit prevents liquid from the liquid supply or the vessel from flowing into the compressor. A corresponding process is provided for transferring a liquid, in discrete amounts or "slugs," from a liquid supply to another location. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority of provisional patent application Ser. No. 60/694,189 filed on Jun. 27, 2005, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a system and method for investing through exchange-traded funds (ETFs).
BACKGROUND OF THE INVENTION
[0003] An ETF is an investing tool that is similar to stocks, except that the shares of a given ETF represent an index of stocks, other securities or other investments rather than a single company stock. Similar to mutual funds, ETFs provide an investor with various types of diversity within a single fund. However, ETFs provide the added benefit of lower expenses, greater transparency, better tax efficiency, and flexibility. For example, unlike mutual or index funds, whose shares may only be bought at the end of the day based on that day's closing price or net asset value as of 4:00 pm on any given day, ETF shares may be purchased intraday, at any time during the trading day, in the same way stocks are traded. Examples of ETFs are the Standard & Poor's Depository Receipt (SPDR), otherwise known as spider, that trades as a stock on the American Stock Exchange and is an index of, or otherwise represents, the S & P 500; Diamonds (DIA) that trades as a stock on the American Stock Exchange and is an index of, or otherwise represents, the thirty stocks in the Dow Jones Industrial Average; Cubes (QQQQ) that trades as a stock on the NASDAQ and is an index of, or otherwise represents, the NASDAQ 100.
[0004] However, ETFs, particularly real estate based ETFs, can be limiting because each such ETF is an index of multiple types of asset classes of real estate whose ratio and types within a single ETF is predetermined by the ETF sponsor's selected index. For those investors who seek to participate in a particular asset class or particular sub-market within a specific sector, the trading characteristics of an ETF are currently not available. For purposes of describing the invention, currently available broad or sector based ETFs are referred to herein as macro ETFs as opposed to the novel sub-sector ETFs of the invention referred to herein as micro ETFs.
SUMMARY OF THE INVENTION
[0005] It is therefore a primary object of this invention to provide a system and method for providing micro ETFs that are differentiated by asset sub-class and/or by sub-market and/or by sub-sector.
[0006] This invention relates to a system and method for investing through exchange-traded finds (ETFs) and more specifically, in the preferred embodiment of the system and method, to investing through real estate sub-sectors or sub-classes (micro ETFs) that are classified using the appropriate asset class or sector terminology. For example, within the sector of real estate, asset classes may include, but are not limited to, industrial, retail, residential, and/or hospitality, and/or market and sub-market classes based on geographic regions in the United States or elsewhere, not previously available to investors through ETFs.
[0007] This invention features a method for offering micro ETFs comprising the steps of: providing a sector sub-class specific exchange traded find comprising a plurality of shares, offering the shares for sale, and selling one or more of the shares to one or more qualified buyers. The step of selling may comprise selling the shares at any time intraday. The sector sub-class specific exchange traded fund may further comprise a plurality of share classes, and the step of selling may further comprise selling a plurality of shares specific to one or more of the share classes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Other objects, features and advantages of invention will occur to those skilled in the art from the following description of the preferred embodiments and the accompanying drawings, in which:
[0009] FIGS. 1 A-E are schematic diagrams of a plurality of preferred embodiments of the micro ETFs of the system and method of the invention; and
[0010] FIG. 2 is a flow chart of the preferred embodiment of the methodology of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] The invention features a system and method that provides investors with a means for investing in specific sub-sectors and sub-classes of assets such as real estate holdings using an ETF structure. Since the system and method of the invention are novel and there is not any known terminology that would adequately describe the invention in short form, the ETFs of the invention are referred to herein as “micro ETFs” for the purpose of describing, but not limiting, the invention.
[0012] Schematic diagrams of a plurality of preferred embodiments of the micro ETFs, any one or more of which may be used in the system and method of the invention, are shown in FIGS. 1A-1E . Although the examples described are based on the real estate sector, the system and method of the invention may be modified for other potential sub-sectors or sub-classes of assets that are traded or could be traded and that can be further sub-classified. For example, the packaging industry is made up of non-competing businesses in the plastics packaging, paper packaging and glass packaging industries.
[0013] REITs commonly own and operate properties in a specific sub-sector of the real estate sector. Some such sub-sectors include residential, office buildings, shopping centers, regional malls, diversified, industrial facilities, mixed (industrial and office), health care, lodging/resorts, mortgage, specialty, and self storage.
[0014] As shown in FIG. 1 , each of the micro ETFs of the invention comprise, for example, a plurality of real estate investment trusts (REITs) that are invested in a single sub-sector. For example, micro ETF 12 ( FIG. 1A ) comprises lodging/resort sub-sector REITs; micro ETF 14 ( FIG. 1B ) comprises retail sub-sector REITs; micro ETF 16 ( FIG. 1C ) comprises industrial sub-sector REITs, micro ETF 18 ( FIG. 1D ) comprises healthcare sub-sector REITs, and micro ETF 19 ( FIG. 1E ) comprises residential sub-sector REITs. Any one of these micro ETFs can be further structured based on any number of sector and/or sub-sector relevant variables such as capitalization, geographic region, and/or asset quality. The variables and combinations are virtually limitless. For example, micro ETF 12 comprises the top 5 , micro ETF comprises the top 10 , micro ETF comprises the top 50 , and micro ETF 18 comprises the top 100 , based on capitalization. Micro ETF 19 represents an undefined group that could be based on any one or more variables, such as geographic location within the residential apartment sub-sector
[0015] As of May 30, 2005, according to Thomson Financial Services, there exist a total of twenty-one exchange-traded funds (ETFs) available in the marketplace that comprise real estate equities. Eighteen are listed as closed-end funds and four are listed as index funds. Each of these ETFs represents a diversified mix of shares in REITs which themselves are unique products in the public markets. Most REITs specialize in investing in one type or specialized sub-sector of the vast real estate industry: residential, industrial, warehouse/manufacturing, lodging/resorts, retail regional malls, retail strip centers, self-storage, and health care, for example. A minority of REITs are diversified by property type. All of the REIT based ETFs hold a diversified mix of REITs—none holds a portfolio of REITs based on one sector, sub-sector, or sub-class of the real estate industry.
[0016] The largest current closed-end REIT ETF is ING Clarion Global Real Estate Income Fund with $2.5 billion under management. The smallest is AEW Real Estate Income Fund with $105 million. Similarly, the largest index REIT ETF is iShares Cohen & Steers Realty Majors Fund at $1.1 billion and the smallest index REIT ETF is Vanguard REIT VIPERS with $144 million.
[0017] As indicated, the real estate industry is segmented by asset class (aka sub-class) or sub-market. Institutional investors pay attention to the weighting of each asset class when they make investment or acquisition decisions. At the institutional ownership level, specialization in a particular asset class expresses expertise, and therefore permits the owner to use its expertise to its advantage.
[0018] Most real estate professionals' vocabulary and mindset are therefore based on their participation in a specific sub-class within the industry. A “hotel person,” “retail expert,” or “class A office developer” are ways these professionals identify with their product. This is reflected in the sector-specific holdings of the REITs themselves.
[0019] Over the last 10 years, the real estate sector has become an ever more accepted institutional investment, e.g. for pension funds of all descriptions from corporate to public sector. As a result many institutional investment portfolios have increased their real estate investment allocations from originally below 5% to over 15% of their total investment portfolio. Many institutional investors invest directly in real estate in segregated or “separate” accounts that hold title to the real estate in their name (thus direct investment) and managed by real estate professionals, or the institutional investors invest indirectly in real estate through ownership of REIT shares or by investing in co-mingled funds managed by pension fund advisors. The combination results in real estate as one of the largest portfolio allocations of institutional investors.
[0020] Investments in real estate by pension funds are often through co-mingled funds managed by pension fund advisors. These advisors further specialize in types (sub-classes) of investments, typically as to the quality of the asset: class A, B or C represents the quality of the location, building materials, size, marketability, etc. “Core,” “core plus,” or “value added” represent various relationships between risk and reward. Whatever asset class mix a pension fund advisor chooses to represent in this matrix, they prefer to specialize in that single asset class. Institutional investors view departures from these traditional specialized asset classes unfavorably because departures from the advisor's asset class specialty confuses the institutional investor's investment decision. This characterization is significant because the pension fund's portfolio manager reserves the right and obligation to diversify the risk of each class of real estate it may be holding. The system and method of the invention can accommodate such traditions. The micro ETFs of the invention may be divided into share classes to enable investors to purchase shares from any one of more of the offered subclasses. These share classes can be based on any number of variables, both traditional and new variables unique to micro ETF sub-classifications of the invention that will inevitably develop along with the demand for these micro ETF sub-classifications.
[0021] As noted, the system and method of the invention, when applied to the real estate market, provide the trading characteristics of an ETF that are currently not available to individual investors who seek to participate in sub-sectors or sector sub-classifications in the real estate markets. The system and method of the invention provide a novel means for sector sub-classification activities. If, for example, one felt that the hospitality industry is in recovery, one could purchase a lodging/resort ETF. Should a travel recession be imminent, one could short the lodging sector ETF. Real estate professionals could likewise balance their portfolios should their exposure in a certain area be unsuitable because, for example, they hold a large number of rather illiquid hotels as direct investments, and require a hedge in a suddenly down trending market.
[0022] Such sector ETF sub-classes can now become an essential part of many investment or trading strategies. Just as “industrials” are sectored in investment research departments and portfolio management departments by industry, e.g. paper and forest products, computing, pharmaceuticals, automotive, etc., real estate sectors will be available to these same investors as sub-classes, or micro ETFs, through the system and method of the invention.
[0023] A micro ETF of the invention can hold, for example, large numbers of REITs specializing in a single sector sub-class and, as such, becomes an analogue for that entire sector's sub-class. For example, a retail strip center-based micro ETF becomes the “market on strip centers”. Further, such large holdings will diversify such strip center REITs as to location, property management, tenant exposures, etc. and become a surrogate for all strip centers with which one could participate in or hedge against holdings in specific geographical markets or exposures to strips with common tenancies.
[0024] The system and method of the invention can be restructured and/or applied to all types of micro ETFs of the invention. For example, offerings using the invention can be structured as closed-end funds or indexes for any and all types of sectors and even more specifically to one or more types of groupings within a given sector. For further example, there are currently over 17 diversified REITs with market caps in excess of $25 billion, there are 12 health care REITs with caps over $14 billion, there are 24 office REITs with caps exceeding $56 billion, 15 industrial/mixed REITs with caps over $40 billion, 5 self-storage REITs with caps over $11 billion, 22 residential apartment REITs with capping over $46 billion, there are 24 shopping center/free standing retail REITs capping over $39 billion, 9 regional mall REITs capping over $47 billion, and 18 lodging/resort REITs capping over $16 billion. A given sector specific sub-class ETF of the invention could utilize a structure that includes a certain category within a particular sector such as ratio based groups, e.g. the five largest or 10 largest. The variables are innumerable and can be structured based on market demand. Depending on the structure or strategy desired, SEC requirements relating, for example, to the number of REITs in a larger pool of REITs must be followed. Alternatively, a given micro ETF of the invention could be indexed, or combined with logically related variables such as regional malls with strip center/free standing retail.
[0025] Many ETFs trade off of an index. The invention contemplates employing one or more existing indexes, and/or creating one or more indexes. One existing REIT index is the FTSE NAREIT US Real Estate Index Series. An example of an index that could be created for use in the invention would be a lodging index made up of REITs that own shares in the lodging real estate sub-sector. Examples of indexes for different asset sub-sectors for the invention could be an index created by an academic institution, an index designed by a commercial institution, or an index designed by a government agency.
[0026] The invention can also apply to indexes that include companies involved in non real estate-based sub-sectors and sub-classes. Examples of the almost limitless possibilities of sub-sectors or sub-classes of assets include: sub-sectors of the paper business, including Kraft paper, writing paper, tissue paper, linen or rag-based paper, etc; sub-classes of the software business, including virus protection, operating systems, productivity, internet-based, gaming, etc.; or sub-classes of the computer memory business, such as hard drives, RAM, ROM, flash, etc.
[0027] The steps taken to accomplish the methodology 30 of the preferred embodiment of the invention, FIG. 2 , contemplate licensing or creating an appropriate index that includes sub-sector or sub-classes of assets, step 32 , writing a prospectus based on the index parameters, step 34 , securing exemptive approval from the SEC, step 36 , securing an index sponsor and advisor, step 38 , listing the index on an exchange, step 40 , and then trading the ETF shares as done with any ETF, step 42 . The micro ETFs of the invention can be structured for trading on any of the available exchanges. Depending on the exchange of choice, once the SEC or other jurisdictional authority approves a given micro ETF of the invention, the system can be run and managed through any of the known means available for trading securities.
[0028] Although specific features of the invention are shown in some drawings and not others, this is for convenience only as the features may be combined in other manners in accordance with the invention, which is defined only by the claims. | A method for accomplishing sub-sector specific investing. A sector sub-class specific exchange traded fund (ETF) having a number of shares is created. The shares are offered for sale, and one or more of the shares are sold to one or more appropriate buyers. | 6 |
RELATED APPLICATIONS
[0001] The invention relates to methods and devices for regulating the filling level in measuring cells of ion cyclotron resonance mass spectrometers so that it is optimal for mass resolution and mass accuracy.
BACKGROUND OF THE INVENTION
[0002] Ion cyclotron resonance mass spectrometers (ICR-MS), also known as Fourier transform mass spectrometers (FTMS) or, in full, as Fourier transform ion cyclotron resonance mass spectrometers (FTICR-MS), are at present the mass spectrometers that offer the highest mass resolution and the most accurate measurement of mass. In these spectrometers, the ions are excited into cyclotron movement under ultrahigh vacuum conditions in a very intense magnetic field of seven, nine, twelve or even fifteen Tesla, generated by superconducting coils held at the temperature of liquid helium, and the frequency of these circulating movements of the ions is measured. The frequencies are inversely proportional to the masses of the ions. Since the magnetic field generated by the superconducting coils is extraordinarily stable, and since frequency measurements are amongst the most accurate measurements that can be taken by today's physical technology, the masses of the circulating ions can be determined with greater accuracy than by any other type of mass spectrometer.
[0003] Unfortunately, this ion cyclotron frequency is shifted by the space charge that is created by the ions in the measuring cell of the ICR-MS. A “reduced cyclotron frequency” is measured, which is non-linearly dependent on the strength of the space charge. This has been known for a long time. The publication by J. B. Jeffries, S. E. Barlow and G. H. Dunn, International Journal of Mass Spectrometry and Ion Processes 54, 169-187, (1983) gives a theoretical description of the frequency shift as a consequence of space charge. If the space charge varies from one scan to the next because it is not regulated, it can cause a shift in the mass signal that differs every time.
[0004] At higher ion densities, a further undesirable phenomenon, known as “peak coalescence”, occurs in ICR mass spectrometry. Signals from ions whose masses only differ very slightly converge, and in extreme cases the ion signals may even completely merge. The result of this merging is, in most cases, another high-resolution ion signal that wrongly indicates an apparent mass lying between the true masses of the two ion species. The analysis of ion signals that lie very close together is, however, a task that ICR mass spectrometers are often called upon to perform.
[0005] Any kind of frequency shift will result in incorrect mass measurements, and must therefore be avoided. Control methods for filling the measuring cell of an ICR-MS are therefore described in patent specification U.S. Pat. No. 6,555,814 B1 (G. Baykut, J. Franzen). The control methods described there, however, always refer to the measurement of the total ion current (or of a fixed proportion of the total ion current) alone, with the result that the regulation of the filling level is always focused on the total ion charge that has been inserted into the measuring cell. Experience, however, shows that maintaining a constant charge quantity does not protect against various kinds of non-reproducible frequency shifts. In addition to the total charge, the precise composition of the mixture of ions of different mass and charge also plays a role, as is already clear from the phenomenon of ion signal merging that has been mentioned above.
[0006] Electrospray ionization is nowadays the most widely used ionization method for the ICR mass spectrometry of biomolecules. In this method, ions are generated out of the solution of the analyte molecules at atmospheric pressure under high voltage (3-6 kV) between an electrospray needle and a counter-electrode. Although the spraying procedure is often supported by a slow, finely controllable spray pump (or by a liquid chromatography feed pump, known by the acronym HPLC), the driving force of the spraying method is the detachment of small, charged droplets resulting from a high ion density on the liquid surface (Coulomb repulsion) under the influence of a powerful electrical field. A “dry gas” that flows in the direction opposite to that of the flight of the charged droplets causes the solvent to evaporate from the droplets (the desolvation process), therefore causing the droplet radii to diminish. As a result of the Coulomb forces that have been strengthened in this way, ionized molecules are evaporated, in most cases in multiply protonated form, i.e. as positively charged ions. These ions are fed for measurement to the mass spectrometer through an inlet capillary, a multi-stage vacuum system and a multipole ion guide.
[0007] Electrospray ionization under atmospheric pressure has made it very easy to couple separation methods for dissolved analyte substances, such as liquid chromatography or capillary electrophoresis, directly to the mass spectrometer. Ionization by laser desorption (LDI) has for a long time been used successfully to transfer large organic molecules from a solid surface into the gaseous phase, and thereby to ionize them. A special type of LDI is ionization by matrix-assisted laser desorption (MALDI). MALDI involves the analyte molecules being mixed with what is known as a matrix substance. The ratio of analyte to matrix molecules here is typically between 1:10 2 and 1:10 4 . The laser beam is absorbed by matrix molecules; in the process, a portion of this matrix material evaporates, taking analyte molecules with it into the gaseous phase. The process partially ionizes them. In most cases the ionization occurs by proton acceptance. Substances used as a matrix are most often proton donors, i.e. substances that easily give up protons.
SUMMARY OF THE INVENTION
[0008] According to the invention, an ICR mass analyzer and a reference mass analyzer are operated in parallel, and a fraction each of the same mixtures of ions obtained from the same flow of substance mixtures by the same ionization methods are supplied to both mass analyzers. The reference mass spectra from the reference mass analyzer are then used to extract parameters that can be used to control the filling process of the measurement cell of the ICR mass analyzer. The two mass analyzers can belong to two different mass spectrometers, each having, for instance, their own ion sources, but may also be integrated into a single device.
[0009] The mixtures of ions can be fed to the reference mass analyzer somewhat earlier than to the ICR mass analyzer, in order to provide sufficient time to evaluate the reference mass spectrum and to control filling of the measuring cell of the ICR mass analyzer at exactly the moment at which the same ion mixture that was measured by the reference mass analyzer is fed to the ICR mass analyzer. This is of particular importance in the case of quickly changing sample substance mixtures, as delivered by separation methods like liquid chromatography or capillary electrophoresis.
[0010] The flows of substance from separation procedures of this type can be coupled indirectly, for instance by coating a MALDI sample support plate, or may be coupled directly, for instance through a splitter that guides the eluate to two ion sources belonging to the two mass spectrometers. A delay loop in the capillary feed line can then be used to supply the ICR mass spectrometer with the mixture of substances from the separation process somewhat later. However, it is also possible for the mixtures of substances to be ionized in just a single ion source, and for the ion beam to be split in the vacuum system before the two partial beams are fed to the two mass analyzers. The splitter may operate in space or in time: it may generate two parallel ion beams for the two analyzers, or may sent a single beam alternately to the two mass analyzers.
[0011] The filling of the measuring cell in the ICR mass spectrometer should be regulated with the aid of a parameter that is obtained from the reference spectrum. This can be the integral of all the ion masses in the ion current, but may also be a mass-dependent, weighted integral taken over the ion current. A parameter that describes the largest collection of ions in a restricted range of masses within the mass spectrum has been found to be particularly favorable. The parameter can thus be calculated as the “maximum of a sliding average”, where the sliding average is obtained by multiplying the reference spectrum with a sliding notch function. The maximum of the sliding average obtained in this way then forms the regulating parameter. The notch function can be a rectangle, whose width can be specified on the mass scale (the normal sliding average), but may also be a triangular or Gaussian function (a weighted sliding average). This method permits filling in which the highest intensity of a mass range with one or more strong mass signals is used as the regulating parameter, thus exploiting the observable effect that, in practice, ions of quite different masses cause very little deterioration in the resolution or the mass accuracy. Of course, any mixture of the functions mentioned above can be used.
[0012] The use of the maximum of a sliding average as regulating parameter is interesting: if, for instance, the mass spectrum consists of 10 ion signals of the same intensity, and if the masses are evenly distributed over the measured mass range, the measuring cell can, without deterioration in the measurements, take about 10 times as many ions as it could if only a single ion species were present. This also accords with the observable effects. This can be explained by the fact that the ions of one ion species, which remain substantially together in their orbits, interfere with each other more strongly through Coulomb repulsion than do other ion species, which have their own cyclotron frequency and only occasionally, while overtaking, fly through the cloud of other ion species. However, ions of species whose masses are almost the same cause the regulating parameter to be reduced, in order to avoid both induced disturbances and “peak coalescence”.
[0013] On the basis of further experience it is possible to obtain algorithms for the calculation of the regulating parameter in different ways. For instance, it can be favorable to handle heavy ions in a different way from light ions. This can be done by introducing a mass-dependent weighting factor.
[0014] The reference mass analyzer used in parallel can, for instance, be a time-of-flight mass spectrometer with orthogonal ion injection (OTOF). This time-of-flight mass spectrometer can be relatively small, since high mass accuracy is not important. Even with a flight-tube only 30 centimeters long, a spectrometer with a reflector can achieve a resolution of about 3000 or 5000, which is quite adequate for the present purposes.
[0015] Ideally the reference mass spectrometer would use the same ion generation and ion guide system as the ICR spectrometer, in other words the same ion source, same ion guide, and, if relevant, the same ion selection and ion fragmentation stages. It is then possible for all the processes to which the ions are subjected on the path to the mass-spectroscopic analyzer itself to be carried out in the same way.
[0016] The two mass analyzers can also share parts of the vacuum pump system. They can even share parts of the ion generation and further ion guidance systems, in which case the ion currents will have to be split somewhere before the two mass analyzers. The common ion guidance systems may include ion selection and ion reaction stages, for instance, ion fragmentation reactions. The splitting can involve a partition of the ion currents that remains constant in time, but can also be a time-based split, feeding the ion mixtures to the two mass analyzers in temporal alternation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The above and further advantages of the invention may be better understood by referring to the following description in conjunction with the accompanying drawings in which:
[0018] FIG. 1 illustrates an example of an arrangement in which two mass spectrometers are operated in parallel in accordance with this invention. The eluate produced by a separation unit is divided by a splitter and sent separately to the two mass spectrometers; the flow to the ion cyclotron resonance mass spectrometer is held back by a delay loop.
[0019] FIG. 2 illustrates an example of an arrangement in which two mass analyzers are integrated in a vacuum system, where they are operated in parallel. The eluate from the separation unit is here only sent to a single ion source, and the ion currents are not divided until they reach the ion flow splitter in the vacuum system. The ion current being sent to the ion cyclotron resonance mass analyzer can be delayed by an ion storage unit.
DETAILED DESCRIPTION
[0020] A first embodiment consists in the parallel operation of an FTICR mass spectrometer and an entirely independent time-of-flight mass spectrometer with orthogonal ion injection. The time-of-flight mass spectrometer is used as the reference mass spectrometer, and has an ion source of the same type, an ion inlet into the vacuum system of the same type and, apart from any differences necessitated by the nature of the system, equipment of the same type for feeding the ions in the vacuum to the mass analyzer. The two ion sources are connected to the same separation equipment through a device for dividing the liquid flows (the “flow splitter”); in this case the separation equipment may consist of apparatus for liquid chromatography or for capillary electrophoresis. The parameter used to regulate filling of the measuring cell of the FTICR mass spectrometer is then calculated from the reference mass spectrum obtained by the time-of-flight mass spectrometer.
[0021] For a slow liquid chromatography process, it is acceptable for the mixtures of substances emerging from the splitter to be delivered synchronously to the two ion sources. Recording the reference mass spectrum in the time-of-flight mass spectrometer only takes a few tenths of a second, and the evaluation required, up to calculation of the parameter used to control the filling of the FTICR mass spectrometer, adds only a few tenths of a second. During this period of between a half and a whole second, the mixture in the eluate emerging from the liquid chromatography unit only changes very little; the regulating parameter calculated on the basis of the reference mass spectrum can well be used here, even though a short time does elapse between measuring the reference mass spectrum and filling the measuring cell.
[0022] Modern separators, however, are achieving increasingly sharp separations, and consequently shorter and shorter peak widths for the separated substances. The use of very fine capillaries in what is called the nano-LC itself shortens the time in which a substance is delivered from more than ten seconds for the normal-LC down to a few seconds in the nano-LC. Capillary electrophoresis can achieve substance peak widths of between one and five seconds. In electrophoretically supported capillary chromatography, the peak widths are already less than one second. Substance peak widths of only a few tenths of a second are also generated in chip-based micro-separation systems. For separation systems of this type, in which the substance mixtures change greatly within tenths of a second, synchronous delivery of the ion mixtures to the two mass spectrometers is no longer usable, due to the time delay between measuring the reference mass spectrum and controlling the filling of an FTICR mass spectrometer.
[0023] The flow of liquid between the splitter and the ion source of the FTICR mass spectrometer can, in these cases, be delayed by a loop in the transport capillary, so that the same mixture of separated substances is measured somewhat sooner in the time-of-flight mass spectrometer. The time difference must be sufficient for a reference mass spectrum to be acquired in the time-of-flight mass spectrometer, for the reference mass spectrum to be evaluated, and for the parameter that will control filling of the measurement cell of the FTICR mass spectrometer to be calculated. This parameter is then used to control filling of the measurement cell of the FTICR mass spectrometer with exactly the same mixture of ions, but delivered a little later. In this method the ion mixture used to fill the cell is identical to the ion mixture whose reference mass spectrum was measured in the time-of-flight mass spectrometer.
[0024] The term “parameter” here should not be restricted to a single number, in spite of the fact that in general a single numerical value is sufficient to control the filling. There are more complicated filling processes, however, where the expression “parameter” should be read as “set of parameters” used to control these filling processes, e.g. by cutting off high ion masses or low ion masses from being filled into the ICR measuring cell. It is even possible to suppress a single kind of ions during the filling process to avoid overloading the cell by just this kind of ions.
[0025] As parameter used to control the filling, it is possible, for instance, to take an integral over the reference mass spectrum; even better is to use a mass-weighted integral over the reference mass spectrum. The mass-weighted integral can take into account the fact that ions of different masses in the FTICR mass spectrometer interfere with each other in different ways.
[0026] In these descriptions, the term “mass” always refers, as is usual in mass spectrometry, to the charge-related mass m/z, that is the physical mass m divided by the number z of elementary charges on the ion.
[0027] The integral taken over the reference mass spectrum does not, however, take into account the fact that the bunches of ions of widely differing masses scarcely disturb each other at all in the FTICR mass spectrometer, since they move with very different orbital frequencies, and therefore only come near to one another when overtaking. The maximum value of a sliding average over the reference mass spectrum is much more favorable, as the regulating parameter; the width of the sliding average should be chosen in such a way that the determination of mass is highly reproducible. In other words, the maximum intensity over all small ranges of masses is looked for. This involves, in a broad sense, the generation of a correlation function K( T ) from the reference mass spectrum S(m) and a notch function A( T −m): K( T )=∫S(m)×A( T −m) dm. For a sliding average, the notch function is rectangular; other notch functions, such as triangular or Gaussian functions, can, however, be used to calculate the regulating parameter. In each case, the maximum of this correlation function, K, is used as the regulating parameter.
[0028] The maximum of the correlation function, K, is logically described here as the “maximum of a sliding average”, since it refers to the maximum intensity in a small range of masses selected from all the small mass ranges in the reference mass spectrum.
[0029] A parameter of this type has surprising properties. If, for instance, the reference mass spectrum has 10 ion species of various masses evenly distributed across the spectrum, it is possible for 10 times as many ions to be loaded into the FTICR mass spectrometer's measuring cell as would be the case if the reference mass spectrum only contained a single ion species. Practical experience indicates very much the same thing: highly linear spectra with large numbers of ion species generally yield much better mass determinations than spectra with very few ion species; in any event this was the case when reference samples with a large number of substances were used during calibration of the FTICR mass spectrometer.
[0030] Even better results can be achieved using parameters obtained from a combination of the maximum of the correlation function (the maximum of the sliding average) with the integral over the mass spectrum (the total charge), because then the influence of the ions with largely different masses can be considered, too.
[0031] The reference mass spectrometer does not, of course, have to be a time-of-flight mass spectrometer. Practically any other kind of mass spectrometer can be used, such as an ion trap mass spectrometer, a quadrupole filter mass spectrometer, or even a magnetic sector field mass spectrometer. The reference mass spectrometer can be very small; it should, however, cover the mass range of the FTICR mass spectrometer. This can already be difficult in the case of ion trap mass spectrometers. If a mass spectrometer with a very low resolution is used, the maximum intensity of the spectrum recorded in this way can itself form the regulating parameter, as the low resolution means that the output is already a sliding average value.
[0032] Furthermore, it is not necessary for the reference mass spectrometer to consist of an entirely separate, independent mass spectrometer. The two mass spectrometers can, for instance, share the same pump system. Both mass spectrometers can be built into the same housing. They can even use the same ion source, in which case the splitter is not located in the feed of substances upstream of the ion source, but in the path of the ion current on the way to the two mass analyzers. Here again, simultaneous supply of the ion mixtures to the two mass analyzers can be avoided through the use of ion storage units. Suitable means are known to the specialist. When the two devices are closely integrated, only a single mass spectrometer is externally visible; internally, however, it consists of two mass analyzers, a reference mass analyzer and an FTICR mass analyzer.
[0033] Within the vacuum system, the ions do not simply have to be guided to the mass analyzers; it is instead possible for individual ion species to be selected by an ion filter and to be fragmented in a fragmentation unit to create daughter ions. These daughter ions are passed on to the mass analyzer, where they are measured as daughter ion spectra. Bearing in mind the idea of the invention, it is clear that the selection and fragmentation units on the two ion paths to the two mass analyzers must be as similar as possible. Here it is particularly expedient if the selection and fragmentation are carried out using devices in which the ion source, ion inlet into the vacuum and other ion guidance systems can be used jointly. Selection and fragmentation (or other types of ion reactions) can then be located on that part of the path through which the ions all travel before the ion current is split and sent separately to the two mass analyzers.
[0034] The necessary equipment is easily determined on the basis of the descriptions of the method and the figures. | The invention relates to methods and devices for regulating the filling level in measuring cells of ion cyclotron resonance mass spectrometers so that it is optimal for mass resolution and mass accuracy. The invention consists in supplying a fraction of the samples to a second reference mass spectrometer operated in parallel, and employing the mass spectra obtained from this reference mass spectrometer to regulate the filling level in the ion cyclotron resonance mass spectrometer. | 7 |
BACKGROUND OF THE INVENTION
The present invention is directed to a linerless, threaded, molded plastic closure, particularly intended for use with glass bottles containing pressurized liquids, but also suitable for use with other types of containers and for non-pressurized applications.
The carbonated-beverage industry produces large amounts of a bulky product in which the container package must meet severe performance requirements while representing a relatively large percentage of the total product cost. Under these conditions, there is an evident need for container closures which are highly efficient and at the same time economical.
SUMMARY OF THE INVENTION
The invention described herein comprises a screw-type, linerless closure for use with threaded containers, molded from polythylene, polypropylene, or other resilient plastic materials suited to the particular application. The use of resilient plastic makes it inherently resistant to shock and abrasion, and as a one-piece molded closure it can be economically fabricated and conveniently recycled. Specific design features as described below are provided to secure high sealing efficiency over a wide range of storage and handling conditions, and to assure safety and conveneince for the user.
In order to accommodate the wide range of dimensional tolerances and surface finishes associated with glass containers, the subject closure employs sealing elements which bear primarily on the top rim of the container outlet. A substantially conical sealing flange of conventional design, depending from the underside of the crown, is deflected into a shape which adjusts itself to fit that surface. Novel supplementary sealing elements cooperate with the flange member to perform specialized functions in the overall sealing system, as described below in detail.
The structure of the internal thread of the closure may also contribute to the efficiency of the sealing action, by utilizing the compensated-pitch principle described in my U.S. Pat. No. 4,294,370 entitled "Thread Construction for Plastic Closures".
An object of the invention is to provide an improved closure for use on a variety of threaded containers.
Another object of the invention is to provide an improved linerless, molded plastic closure which is suitable for use with containers holding pressurized liquids, and which is adapted to the special characteristics of glass containers.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged side view, partially sectioned on the central plane of a closure according to the invention, showing the closure partially installed on a container but prior to sealing contact.
FIG. 2 is a similar sectional side view, the same as FIG. 1 except that the closure has been screwed down firmly onto the container so that the seals are fully deflected and the threads fully loaded.
FIG. 3 is a more detailed view of a portion of the underside of the sealing cone of FIG. 1, as viewed from below.
FIG. 4 is a partial sectional view of an upper portion of FIG. 1, showing alternative designs for the sealing ridge and closure crown.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1, the invention is embodied in a molded plastic, screw-type closure made of polyethethylene, polypropylene, or a similar resilient plastic. The basic structure of the closure comprises a circular crown 1, a concentric cylindrical sidewall or skirt 2 which is integral with the crown, an internal screw thread 3 for mating with a container thread 4, and external knurls or flutes 5 by which the closure may be gripped to rotate it on to or off of the container thread.
Depending from the junction of crown 1 and sidewall 2 is a sealing flange 6 in the form of a truncated cone, having an inside diameter which is approximately the same as that of the top surface or rim 7 of container 8, after installation.
Molded into the under surface of seal 6 is a series of small concentric grooves 9. As shown enlarged in FIG. 3, these are separated by sharp-edged ridges 10 which supplement the operation of seal 6 in a manner to be described. As shown in FIG. 3, the crests of the ridges coincide with the under-surface of seal 6; however, they may also be positioned slightly above or below the surface.
Also depending from crown 1, and concentric with it, is a sealing ridge 11, the effective diameter of the ridge crest being substantially equal to the mean diameter of container top surface 7. Immediately inside or outside of the ridge is a groove 12, the inside location being shown in FIG. 1. The crest of ridge 11 projects below the adjacent plane of the undersurface 13 of crown 1, and groove 12 is recessed into the body of crown 1, so that the volume of ridge 11 below plane 13 is substantially equal to the volume of groove 12 above the plane. The crest of ridge 11 is substantially sharp as molded, whereas the contour of groove 12 is preferably rounded to minimize tension stresses under load. Directly above ridge 11 and groove 12 are a pair of concentric ridges 16 and 17 which are integral with the upper surface of crown 1; the outside diameter of ridge 16 is equal to, or slightly less than, the minimum diameter of groove 12, while the inside diameter of ridge 17 is equal to, or slightly greater than, the maximum diameter of the base of ridge 11, for reasons to be described.
It is contemplated that thread 3 may incorporate the compensated-pitch principle described in my U.S. Pat. No. 4,294,370, previously cited, in order to more effectively equalize thread loading and sealing pressure around the circumference of the closure.
As the closure is screwed on to the container, seal 6 is deflected toward crown 1 until it is compressed between ridge 11 and surface 7 as shown in FIG. 2. During the final stage of tightening, the crest of the ridge applies the axial closing force developed by the screw threads to a narrow zone on the upper surface of the seal, and through it to multiple ridges 10 and surface 7. At the same time, the axial force deflects part of the material of ridge 11 into groove 12, as provided for by the designed volumes of the ridge and groove and in accordance with the resilience of the molding material used.
Although surface 7 is normally made to be as smooth as glass technology permits, it typically possesses more small asperities and larger irregularities than, for example, a molded plastic surface. The small multiple ridges 10, each of which has one-third or less of the volume of ridge 11, are designed to absorb and to fill in the smallest of these asperities. Because the contour of surface 7 may vary from one lot of containers to another, and because the deflection of seal 6 over surface 7 may affect the final position of ridges 10 with respect to ridge 11, it is desirable to provide multiple concentric ridges 10, as shown in FIG. 3, so that one or two of them are sure to be directly underneath ridge 11 and will therefore be deformed into intimate contact with surface 7. It may also be desirable to mold a series of short radial ridges 14 across ridges 10, and of the same height, in order to divide the grooves 9 into compartments, as shown in FIG. 3. This will minimize leakage in case surface 7 should be even more irregular than normal, or if the deflection of seal 6 should introduce any irregularity into the concentricity of ridges 10 with respect to ridge 11.
In addition to supporting multiple ridges 10, seal 6 performs sealing functions of its own. Its flexibility allows it to adapt to larger variations in the contour of surface 7, and any leakage of internal gas pressure into space 15 above seal 6 will increase the axial sealing force on surface 7. This action is of particular value while the closure is in the process of recovering from abnormal top-load pressures, as detailed below.
The primary axial sealing pressure is applied through ridge 11, which is designed to be pliable enough to accommodate itself to the larger irregularities of top surface 7, deforming into groove 12 as required for this purpose. Groove 12 has a rounded root to minimize the development of notch stresses in that portion of crown 1 when under tension load from high gas pressures.
Groove 12 also operates to enable the structure to better resist the effects of abnormal top-load pressure, which may be encountered when open-top cases containing the product are stacked several units high during storage. If no relief were provided under such conditions, ridge 11 might be deformed so severly as to prevent adequate recovery after removal of the excess load, thereby permitting greater subsequent leakage. However, the construction as disclosed herein allows ridge 11 to be deflected into the space of groove 12, thereby limiting its deformation and permitting the excess load to be shared by a larger portion of surface 13. The presence of seal 6 also reduces the concentration of pressure on ridge 11. As a result of all these factors, ridge 11 is less likely to be stressed beyond its compressive limit. It will then retain sufficient resilience to restore much, it not all, of its sealing efficiency after removal of the excess load, any gas pressure which leaks into space 15 will supplement this resealing action by increasing the pressure on the existing contact zone between the underside of seal 6 and surface 7.
The resistance of ridge 11 to permanent deformation may be still further improved by the addition of ridges 16 and 17. Since any top-load pressure applied to these ridges is transmitted primarily to those portions of surface 13 which are directly underneath, just inside of groove 12 and outside of ridge 11 respectively, and from there directly to seal 6 and surface 7, transient overloads are more widely distributed, and correspondingly less pressure is applied to ridge 11.
FIG. 4 shows alternative constructions for the sealing ridge and for the central portion of the crown. In place of the assymmetrical combination of ridge 11 and groove 12, a symmetrical ridge 20, flanked by a pair of smaller grooves 21 and 22, may be preferred. For some applications the grooves may be omitted, and the ridge only used in the conventional way.
To further increase the resistance of the closure seals to top-load pressure, the inner portion of the crown may be offset upward until its upper surface 23 is substantially flush with the tops of ridges 16 and 17. The corresponding lower surface 24 may then be recessed enough to maintain the desired effective thickness of material. If desired, one or more slots 25 may be added to ridge 17 to drain off unwanted process or rainwater.
Since the internal gas pressure of carbonated beverages or other pressurized liquids normally causes the center of the closure to dome upward noticeably, any flattening of the dome is resisted by the gas pressure. This relieves some of the excess weight on the closure, which might otherwise result in excessive deformation of the sealing elements.
In compliance with the requirements of the patent statutes I have herein shown and described a preferred embodiment of the invention. It is, however, to be understood that the invention is not limited to the particular construction shown, the same being merely illustrative of the principles of the invention and its scope as determined by that of the claims. | A screw-type linerless closure molded of resilient plastic is provided with a novel combination of sealing elements for accommodating storage overloads, large container tolerances and variable surface textures, to secure reliable sealing over a wide range of conditions. Operation of the principal sealing ridge is assisted by an adjacent pressure-relief groove, or grooves, and by separate overload-resisting elements. A supplementary sealing flange is also provided to accommodate irregularities of the mating surface of the container. | 8 |
BACKGROUND OF THE INVENTION
This invention concerns weaving machines with an improved weft thread supply, more particularly weaving machines of the type in which each weft thread remains attached to the edge of the cloth between successive picks, as for example on rapier weaving machines.
It is known that the weft thread supply on certain types of weaving machines, such as rapier machines, includes one thread preparation mechanism for each type of weft thread, plus a thread presentation mechanism for presenting the respective weft threads in the path of a feed gripper. The thread preparation mechanisms each include a thread package, a prewinder mechanism and a thread braking device.
From Belgian patent No. 901.969 it is known for a thread detector to be included in the thread preparation mechanism. The thread detector is connected to the control unit such that whenever a broken weft thread is detected in a corresponding thread preparation mechanism, the machine automatically switches to another thread preparation mechanism, so that weaving can continue.
On rapier weaving machines in which the weft threads are cut loose at the beginning of their insertion after being presented in the path of the feed gripper, and then after insertion remain attached to the thread package back from the cloth edge until a new insertion of the corresponding weft thread occurs, the abovementioned method of automatically switching between thread preparation mechanism poses a problem. On such rapier weaving machines, the weft threads are drawn along with the cloth at a constant, if low, speed. This means that if a thread break occurs in a thread preparation mechanism, the section of thread still attached to the cloth edge is eventually drawn out of the thread preparation mechanism and falls into the path of the rapier. Such a section of weft thread is then carried into the shed along with the next weft thread to be inserted, so that a fault occurs in the cloth, of a type which is difficult to detect by conventional weft detectors.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a solution to the disadvantage just described, by ensuring that, before there can be a fall-off in the thread tension in a broken weft thread between the thread presentation mechanism and the edge of the cloth, an output signal is provided for further processing such that either an alarm is given, the weaving machine is stopped, or an alarm is given followed a certain time later by a machine stop.
The invention concerns a weaving machine with an improved weft thread supply, of the type in which each weft thread remains attached to the edge of the cloth between successive picks. The weft thread supply includes at least two thread preparation mechanisms each of which comprises a thread package, a prewinder and a thread braking device. A thread break detector is mounted somewhere along the path of the weft thread, more particularly between the thread package and the thread braking device, and a thread presentation mechanism is positioned after the thread preparation mechanism. Also included is a control unit connected to the thread preparation mechanisms, the thread presentation mechanism and the thread break detector, such that if the thread break detector detects a thread break, the control unit deactivates the thread preparation mechanism in use and also its corresponding thread guide element of the thread presentation mechanism, after which weaving continues with only one or more of the other thread preparation mechanisms according to a preset pattern. Finally, the improved weft thread supply of the invention includes a monitoring device which, if the thread break detector detects a thread break, sets a limit to how much farther the broken thread still attached to the cloth can move, and which also provides an output signal for further processing, at least at the moment that the limit is reached by the end of the broken section of weft thread. The monitoring device can consist of a delay circuit included in the weaving machine control which, when the thread break detector has detected a break, lets the weaving machine operate further for a known, predetermined length of time and then automatically brings it to a halt.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to better describe the characteristics of the invention, some preferred embodiments are now described, by way of example only and without being limitative in any way, with reference to the accompanying drawings, where:
FIG. 1 is a perspective view of a gripper weaving machine with an improved weft thread supply;
FIG. 2 is a schematic diagram of the improved supply according to the invention, including a schematic partial perspective view of the weft insertion mechanism and shed of the weaving machine of FIG. 1;
FIG. 3 is a detailed representation of the weft thread supply according to the invention;
FIGS. 4 to 9 are schematic diagrams of various possible variants of the embodiment shown in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a rapier weaving machine in which, as is known, the supply 1 consists of a number of thread preparation mechanisms 2 to 5, each of which consists of a number of thread packages 6 to 9, prewinders 10 to 13 and a thread presentation mechanism 14 for the purpose of bringing the weft threads 15 to 18, which are attached to the cloth 19, into the path of the feed gripper, in order to provide the weft. Also shown schematically in FIG. 1 are the receiving gripper 21 and the main drive 22 of the weaving machine. The supply 1 according to the invention is now described in detail with reference to the block diagram in FIG. 2.
The supply consists of a combination of: the thread preparation mechanisms 2 to 5, each of which consists of at least a thread package 6 to 9, a prewinder 10 to 13 and a thread braking device 23 to 26; at least one thread break detector 27 positioned in the path of the weft thread 15, more particularly between the corresponding thread package 6 and the corresponding thread braking device 23; a thread presentation mechanism 14 positioned after the thread preparation mechanisms 2 to 5; a control unit 28 connected to the thread preparation mechanisms 2 to 5, the thread presentation mechanism 14 and the thread break detector 27; and a monitoring device 29 including means to set a predetermined limit G to how much farther the broken section of weft thread 15A can move when the thread break detector 27 detects a thread break 30. The control unit 28 is designed so that if the thread break detector 27 detects a thread break 30, the thread preparation mechanism 2 in use is deactivated and the corresponding weft thread 15 (15A) is no longer presented by means of the thread guide element 34 of the thread presentation mechanism 14. Instead another thread preparation mechanism 3 to 5, according to choice, is activated instead. Clearly, if weaving is being carried out using all four of the thread preparation mechanism 2 to 5 according to a particular pattern, then when a break occurs this operating pattern is modified so that weaving can continue with only the remaining three thread preparation mechanisms 3 to 5. As already mentioned, the use of such a control unit to switch over to another thread preparation mechanism if a fault is detected is known from Belgian patent No. 901.969 granted to the applicant.
The above-mentioned monitoring device 29 supplies an output signal 31 whenever the free end 32 of the broken section of weft thread 15A has reached the limit G or is considered to have reached this limit. The output signal 31 can then be processed in any desired manner, for example in order to activate an alarm signalling device 33 or to shut off the main drive 22 of the weaving machine.
The operation and the purpose of the invention can be simply deduced from FIG. 2. During normal operation of the weaving process, as they are led along the thread guide elements 34 to 37 of the thread presentation mechanism 14 which are movable up and down, the weft threads 15 to 18 are kept taut since they remain attached to the edge of the cloth 38 and also pass through the thread braking devices 23 to 26. Since the cloth 19 moves forward continuously, the weft threads 15 to 18 are also continuously moved forward slowly when they are not inserted into the shed 39.
The insertion of the weft threads is itself common technology. As shown schematically in FIG. 2, the required thread guide element 37 is moved down so that the corresponding weft thread 18 is brought into the path of the feed gripper 20 and so carried into the shed 39. At the beginning of the insertion the weft thread 18 is cut free from the cloth edge 38 by a cutter 40. Once the weft thread has been beaten up between the warp threads 41 and 42, it is not cut free again at the weft insertion side until another weft thread of the same weft yarn is inserted.
Should a thread break 30 occur, the operation of the weft supply 1 is as follows. The thread break 30 is detected at a certain moment by the thread break detector 27. By means of the control unit 28 the thread preparation mechanism 2 is deactivated and the thread guide element 34 of the thread presentation mechanism is no longer presented, while another thread preparation mechanism 3, 4 or 5 is activated in its place. Obviously, for this purpose it is possible to use one or more thread preparation mechanisms which were already in use before the weft break occurred; after the thread break, these will then take over the task of the deactivated thread preparation mechanisms 2, in addition to their normal task. Thread presentation will then continue using only the thread guide elements 35 and/or 36 and/or 37. The section of weft thread 15A will however continue to move forward with the cloth. If no special measures are taken in order to carry out a repair, after a certain time the end 32 will come out of the thread braking device 23, so that the section of weft thread 15A will come loose and due to its own weight will sag between the corresponding thread guide element and the edge of the cloth 38 and so come into the path of the feed gripper 20, resulting in the disadvantages mentioned in the Background of the Invention.
In the present invention, however, as a result of the signal from the abovementioned thread break detector 27, the monitoring device 29 is activated, so that said monitoring device supplies an output signal 31 whenever the free end 32 runs through one or more preset limits G. The limits G are situated so that the thread runs through them before it reaches the thread braking device 23. In this way, either the alarm signalling device 33 can be activated or the main drive 22 of the weaving machine can be shut off before the section of weft thread 15A comes loose from the thread braking device 23. In this way, it is possible to intervene manually in good time or to intervene automatically by stopping the weaving machine.
Clearly, in a similar way as for thread preparation mechanism 2, the other thread preparation mechanisms 3 to 5 can also be equipped with thread break detectors 43 to 45 and connected to the monitoring device 29.
FIG. 3 shows a practical embodiment corresponding to the block diagram in FIG. 2, more particularly for two thread preparation mechanisms 2 and 3. In this configuration, the weft threads 15 and 16 pass successively and respectively through the detectors 46 and 47, the prewinders 10 and 11, the detectors 48 and 49, the thread brakes 50, 51 and 52, 53, thread compensators 54 and 55, a weft detector 56 and the thread guide elements 34 and 35 of the thread presentation mechanism 14.
The prewinders 10 and 11 each consist of a prewinder drum 57 and a rotating winding tube 58 through which the turns 59 are wound onto the prewinder drum. The prewinders each have one or more turn detectors 60 which monitor the quantity of thread on the prewinder drums 57.
The detectors 48 and 49 are preferably eye-shaped motion detectors, which also form a guide for the threads as these leave the prewinder drums 57.
The weft detector 56 consists of a series of motion detectors, of which two, 61 and 62 respectively, are used by the weft threads 15 and 16. These detectors supply a signal which is a function of the motion of the threads 15 and 16. The guide bar 63 ensures that the weft threads remain in permanent contact with the side walls of the motion detectors.
Finally, also shown schematically in FIG. 3 are the brush brakes 64 which operate on the winding drums 57, since as explained below these can also be of importance.
Depending on how the abovementioned components are connected to the control unit 28 and the monitoring device 29, a supply 1 according to the invention can be accomplished in various ways.
Clearly, in the practical embodiment, the thread detectors 27, 43, 44 and 45 mentionded in FIG. 2 can also consist of the detectors 46, 47 shown in FIG. 3 or the turn detectors 60. The turn detector 60 can be single or double. In the latter case, this means that there is a minimum as well as a maximum detector The turn detector 60 is able to determine the quantity of the thread on the prewinder, which in turn determines the length of the delay after which the weaving machine must be stopped after a thread break.
In order to set one or more limits G, one or more detectors 60, 48, 49 and 61, 62 operate with the monitoring device 29.
Some of the possible variants of the practical arrangement shown in FIG. 3 are now described with reference to the schematic diagrams in FIGS. 4 to 9. The embodiments shown all relate to the abovementioned thread preparation mechanism 2.
In each of the embodiments shown in FIGS. 4 to 9, the abovementioned detector 46 mounted in front of the winding tube 58 is used as the thread break detector 27 connected to the control unit 28.
As shown in FIGS. 4 and 5 the monitoring device 29 consists of a connection between the turn detector 60 and the main drive 22 of the weaving machine. The abovementioned limit G in this case is formed by the point at which the turn detector 60 is located. The thread braking device 23 shown schematically in FIG. 2 is in this practical example formed by the brush brake 64.
The operation of the supply 1 operates as follows: as shown in FIG. 4, whenever a break 30 is detected by the detector 46, the control unit 28 and the monitoring device 29 are activated. The control unit 28 ensures that operation is switched to one of the other thread preparation mechanisms 3, 4 or 5 or that, if these thread preparation mechanisms are already in use, they continue to operate according to a preset pattern in such a way that they take over the task of the deactivated mechanism 2. The alarm signalling device 33 can then be activated at that moment, either by the monitoring device 29 or perhaps directly by the detector 46, so that the weaver is alerted to the fact that a break 30 has occurred. Since the cloth 19 moves on, the weft thread 15 is also slowly unwound farther. Once the monitoring device 29, or in this case the turn detector 60 connected to it, does not detect a thread any more, the main drive 22 of the weaving machine is inexorably shut down, whereupon for example a lamp of another color lights up on the alarm signalling device 33. Stopping the weaving machine in good time in this way prevents the broken section of weft thread 15A being inserted into the shed.
FIG. 5 shows another variant. Here, the monitoring device 29 includes a connection between the turn detectors 60 and the main drive 22 of the weaving machine and/or the alarm signalling device 33. The particular feature of this variant is that the monitoring device 29 has a delay circuit and/or an arithmetic unit, such that, from the moment that thread is no longer detected at the turn detector 60, the main drive 22 of the weaving machine can remain in operation for a short while longer. Since there are still a number of turns on the prewinder drum 57, some thread can still be drawn from the prewinder drum 57 for a short while before the thread comes away from the brush brake 64. The length of the interval during which the section of weft thread 15A can continue to move without coming loose from the brush brake 64 can be calculated as a function of the speed at which the cloth 19 moves along, which in turn is a function of the beat-up frequency of the reed and the pick density. When the preset limit G is reached, the main drive of the weaving machine is shut off, and this is made known by a suitable visible signal on the alarm signalling device 33.
In the embodiment shown in FIG. 6, the abovementioned thread braking device 23 includes the thread brakes 50 and 51 instead of the brush brake 64. For the rest, the operation is similar to that of the embodiments shown in FIGS. 4 and 5.
In the embodiment shown in FIG. 7, the monitoring device 29 includes connections between the abovementioned thread detector 48 and the alarm signalling device 33 and the main drive 22 of the weaving machine respectively. The thread braking mechanism is formed by the thread brakes 50 and 51. The operation is similar to that of the embodiments previously described; in other words, when detector 46 detects a break 30, the alarm signalling device 33 is activated, and when detector 48 does not detect a thread any more the main drive 22 of the weaving machine is shut off, so that the broken section of weft thread 15A remains held in the thread brakes 50 and 51. The use of the two thread brakes 50 and 51 offers a greater degree of certainty that the section of weft thread 15A will be held fast.
Clearly, the detector 48 can consist of either a conventional thread detector or a motion detector. The former will detect the presence or absence of a thread, while the latter will detect whether or not the thread is moving.
FIGS. 8 and 9 show another two variants in which use is made of the weft detector 56. The monitoring device 29 in this case consists of connections from the detector 46 and from the weft detector 56 to the alarm signalling device 33 and/or the main drive 22 of the weaving machine. In this case, the monitoring device 29 includes an arithmetic unit which can calculate how much weft thread 15 has passed the motion detector 61, as a function of the signal from the weft detector 56.
The operation is as follows. When the detector 46 does not detect a thread any more, the control unit 28 and the monitoring device 29 are activated. By means of the control unit 28, operation is switched to the other thread preparation mechanisms, or the thread preparation mechanisms in use take over the task of the deactivated mechanism. The broken section of weft thread 15A however continues to advance, since it is attached to the edge of the cloth 19.
Depending on the minimum length of the weft thread between the detector 46 and the thread braking element 23, for example the brush brake 64, from the moment at which no thread is detected any more at the detector 46 because it is pulled along by the cloth, the main drive 22 of the weaving machine is stopped in good time such that the broken section of weft thread 15A is not pulled out of the corresponding thread braking device 23.
FIG. 9 shows a variant of FIG. 8 in which the thread braking device is formed by the thread brakes 50 and 51.
Clearly, a combination of the possibilities described above can be used. For example, in the thread preparation mechanism 2 in FIG. 3 the monitoring device 29 consists of connections from the detectors 46, 60 and 48 to the alarm signalling device 33 and the main drive 22 of the weaving machine. When detector 46 does not detect a thread any more, then for example a flashing light on the alarm signalling device 33 can be activated. When the turn detector 60 does not detect a thread any more, this light can flash faster, and when the detector 48 does not detect anything any more, it can shine continuously.
After that moment, depending on the amount by which the cloth 19 advances, after a certain amount of time or, since the pick density is known, after a certain number of picks, the main drive of the weaving machine is shut off before the free end 32 reaches the thread brakes 50 and 51, by means of an arithmetic unit or a delay circuit. Depending on the type of alarm signal given, the weaver knows how urgently a repair has to be carried out in order to prevent a machine stop.
By combining the detector 46 and a time setting, the rate of flashing of the signal lamp 46 can depend on the amount of time that has elapsed.
Clearly, the weaving machine, and more particularly its improved supply, can be made in different forms and variants while still remaining within the scope of the invention. | A weaving machine is of the type in which the weft thread remains attached to the edge of the cloth between successive picks, the weft thread moving along with the cloth as the weaving process progresses, and in which detection of a thread break causes deactivation of a corresponding thread preparation mechanism and transfer of its task to another thread preparation mechanism. The weaving machine includes a monitoring device which, in the case of a thread break, sets a limit as to how much further the broken section of weft thread which is attached to the cloth can move. The monitoring device supplies an output signal so that further action can be taken to prevent further movement of the broken weft thread along with the cloth. | 3 |
BACKGROUND OF THE INVENTION
Background of the Invention
[0001] The Sandwich has been a primary staple lunch for factory laborers, officer workers, and students for decades. There has long been the problem of the soggy sandwich which makes these meals less appealing. As soon as the sandwich is assembled, the ingredients begin interacting with each other. Breads begin to absorb the moisture from the vegetables and condiments losing its structure. Vegetables begin to wilt and lose their crispness. Meats and cheeses blend losing their distinct flavors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0002] FIG. 1 illustrates an exploded view of a sandwich separator container in accordance with an exemplary embodiment of the invention.
[0003] FIG. 2 illustrates a container lower element with an insertable heating and cooling element in accordance with an exemplary embodiment of the invention.
[0004] FIG. 3 shows an inner platform divider for a sandwich separator container in accordance with an exemplary embodiment of the invention.
[0005] FIG. 4 shows a cross sectional view of a sandwich separator container with sandwich ingredients in accordance with an exemplary embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0006] Described herein is a sandwich container for transporting a sandwich in a disassembled state such that the sandwich can be assembled when one is ready to consume it. The goal of the container is to allow one to enjoy the “just made” sandwich taste which most find to be more desirable than that of a sandwich made hours in advance. The best was to achieve this goal is to keep each element of the sandwich separated until it is time to consume the sandwich, and assemble them then. This requires that various element of the sandwich which may interact have their own compartment, and the compartments be separated in such a way that cross contamination is prevented even if the container is upended or jostled between the time it is packed and when it is unpacked (i.e. wet element kept separated from dry elements).
[0007] Next it is necessary for the container to contain enough compartments for a relatively complex sandwich (i.e. dual condiment compartments, meat, cheese, vegetable and bread compartments), and that there is means for keeping such compartments relatively hotter or colder than the surrounding environment. There needs to be all elements necessary to assemble the sandwich when it is time for consumption (e.g. a knife/spoon). Finally, it must be within a single container to prevent loss or misplacement of any single item.
[0008] The container described herein has individual compartments and/or trays to separate each of the sandwich's major component categories. The components may comprise breads, meats, cheeses, vegetables, and/or condiments. Items which are of a liquid or semi-liquid state, such as condiments, are stored in a compartment with a liquid-proof seal. The container includes a utensil, such as a knife, spoon, or other blade for spreading the condiments on the bread when assembling the sandwich. The included utensil ensures one is available when it is time to assemble and enjoy the sandwich.
[0009] The container may contain heating and/or cooling pads for keeping meats warm and/or keeping vegetables cool. One skilled in the arts would appreciate that heating and cooling pads may be passive thermal reservoirs, active electrical components, chemical components, or other means of maintaining a desired temperature range above or below the environment surrounding the container. One skilled in the art would also understand that the temperature differences may be enhanced and/or retained for longer periods of time by the use of different materials for construction of the pads, compartments, or the use of additional insulation between the desired compartment and the others, or the outside environment.
[0010] Refering to FIG. 1 one sees an exploded view of a sandwich separator container in accordance with an exemplary embodiment of the invention. The sandwich separator container comprises a lid element ( 5 ), and lower element ( 10 ), and an inner platform or divider element ( 30 ). The lower element ( 10 ) has a heating/cooling insertable element ( 20 ) which is held in place with supports ( 25 ) between the two lower compartments.
[0011] The inner platform/divider element ( 30 ) sets inside the lower element ( 10 ) and rest just above the supports ( 25 ) at the center line ( 37 ). The bread tray ( 35 ) rest just above and seals the lower compartment. The inner platform element ( 30 ) has two condiment compartments ( 60 ) which are sealed with a lid ( 70 ). The two condiments compartments ( 60 ) are molded into the inner platform element ( 30 ), and extend down into the lower compartment such that they form a lid over the lower compartment. The inner platform element ( 30 ) also has a detachable condiment utensil ( 40 ). Finger notches ( 80 ) provide a way for the inner platform ( 30 ) to be lifted out of the lower element ( 10 ). Finally the container is covered with a lid ( 5 ) which seals the sandwich container.
[0012] FIG. 2 illustrates a container lower element with an insertable heating and cooling element in accordance with an exemplary embodiment of the invention. Visible are the container's lower element ( 10 ), the insertable element supports ( 25 ), and an insertable heating/cooling element ( 20 ). One skilled in the art would appreciate that other configurations could be utilized which allowed separate heating/cooling elements for each of the lower compartments and would still be encompassed by the disclosures of this application.
[0013] FIG. 3 shows an inner platform divider for a sandwich separator container in accordance with an exemplary embodiment of the invention. The inner platform ( 30 ) has a bread tray ( 35 ) molded into one side, which extend downward from the inner platform ( 30 ). The center line ( 37 ) is where the inner platform ( 30 ) is supported in the container's lower element ( 10 ), and rest just above the insertable heating/cooling element ( 20 ). In the preferred embodiment, a plurality of depressions are molded into one side of the inner platform to serve as condiment compartments ( 60 ) which are sealable by a lid ( 70 ). In an alternative embodiment there may be more than two condiment compartments ( 60 ), or the condiment compartments may be separate containers which could detachable from the inner support tray ( 30 ). There is a reusable condiment utensil ( 40 ) which is included with the container. A finger notch ( 80 ) provides a way to lift the inner platform ( 30 )
[0014] FIG. 4 shows a cross sectional view of a sandwich separator container with sandwich ingredients in accordance with an exemplary embodiment of the invention. Visible is the container's lower element ( 10 ) which has supports ( 25 ) which hold the heating/cooling element ( 20 ) between two compartments which are shown to hold meats (B) and vegetables (C). Just above the vegetables (C) is found a condiment container ( 60 ) holding a condiment (D) which is sealed with a lid ( 70 ) and includes a utensil ( 40 ) for spreading the condiment on the bread (A) which is stored in the bread compartment ( 35 ) located on one side of the inner platform ( 30 ). Finally the container ( 1 ) is closed with the lid ( 5 ).
[0015] The diagrams in accordance with exemplary embodiments of the present invention are provided as examples and should not be construed to limit other embodiments within the scope of the invention. For instance, heights, widths, and thicknesses may not be to scale and should not be construed to limit the invention to the particular proportions illustrated. Additionally some elements illustrated in the singularity may actually be implemented in a plurality. Further, some element illustrated in the plurality could actually vary in count. Further, some elements illustrated in one form could actually vary in detail. Further yet, specific numerical data values (such as specific quantities, numbers, categories, etc.) or other specific information should be interpreted as illustrative for discussing exemplary embodiments. Such specific information is not provided to limit the invention.
[0016] The above discussion is meant to be illustrative of the principles and various embodiments of the present invention. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications. | A container for storing a sandwich comprising a plurality of individual compartments for storing sandwich items individually; wherein all the individual compartments of the container are joinable into a single container for ease of transportation. The individual compartments prevent the items of the sandwich from intermixing and affecting the taste, consistency, and integrity of each of the other elements. Included in the container are all utensils for preparing the sandwich. Individual compartments may be insulated and thus may be kept warmer or cooler than other compartments. | 0 |
This is a continuation of application Ser. No. 08/137,488 filed Oct. 18, 1993, now abandoned, which is a continuation of application Ser. No. 07/870,115 filed Apr. 17, 1992, now abandoned, which is a continuation of application Ser. No. 07/689,105 filed Apr. 23, 1991, now abandoned, which is a continuation of application Ser. No. 07/234,748 filed Aug. 22, 1988, which is now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method of forming a compound semiconductor by use of an organometallic compound starting material.
2. Related Background Art
For preparation of a group II-VI compound thin film according to the MOCVD (Metal organic compound chemical vapor deposition), method of the prior art, a hydride of the group VI element or an alkylated product in the form of R 1 --X--R 2 (X is selected from S, Se and Te), and R 1 and R 2 each represent alkyl) has been used as the group VI element supplying starting material (hereinafter abbreviated as group VI starting material). The method has involved the following problems.
A hydride of the group VI element had too high reactivity with the group II element supplying starting material (hereinafter abbreviated as group II starting material), whereby the reaction in the gas phase cannot be controlled, and therefore crystallinity of the epitaxial film was worsened, or it was difficult to control growth of a thin film.
On the other hand, the alkylated product in the form of R 1 --X--R 2 , which is slightly lower in reactivity with the group II starting material, can be more readily controlled in growth than the hydride, by utilizing higher substrate temperature.
Accordingly, in the case where the above hydride or alkylated product was used as the starting material according to the MOCVD method to selectively form a film on a patterned substrate, formation of a film on the mask surface (non film-forming surface), could not be sufficiently inhibited.
Further, the alkylated product in the form of R 1 --X--R 2 also had problems such as high toxicity and explosiveness.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide a method of forming a crystalline film of a compound semiconductor of high quality which improves growth controllability of a thin film by solving the problems of the prior art as described above.
Another object of the present invention is to provide a method of forming a compound semiconductor thin film of a group II-VI compound on a desired substrate according to the MOCVD method, which comprises using an alkylated product in the form of R 1 --X n --R 2 (n is an integer of 2 or more, R 1 and R 2 each represent alkyl and X represents S, Se or Te) as the organometallic starting material of the group VI.
Still another object of the present invention is to provide a method of forming a compound semiconductor thin film using a starting gas R 1 --X n --R 2 which is by far safer with respect to toxicity and explosiveness as compared with the prior art starting gas in the form of R 1 --X--R 2 .
Yet another object of the present invention is to provide a method of forming a compound semiconductor thin film in which the reactivity with the group II gas is moderate and by which uniformity over a large area can be improved.
Yet still another object of the present invention is to provide a method of forming a compound semiconductor thin film by which the monocrystal ratio can be dramatically improved in crystal formation utilizing selective nucleation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a MOCVD device, and FIGS. 2a-2g are diagrams of the steps of the method of forming a compound semiconductor crystal utilizing the selective nucleation method. FIG. 3 is a graph showing the relationship between the group VI starting material and the monocrystal ratio and FIGS. 4a to 4d are diagrams of the steps of the method of forming a crystal of a compound semiconductor utilizing the selective nucleation method.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a schematic illustration of one of the preferred embodiments of a device for embodying the method for forming a compound semiconductor film of the present invention.
A group II starting material from an introducing inlet 1 and a group VI starting material from an introducing inlet 2 are fed into quartz chamber 7. The starting material gases are mixed near the blowing outlet 3 to form a stable intermediate through chemical reaction, which is then delivered to the surface of the substrate 6.
The substrate 6 is held by a substrate holder 5 heated by a high frequency coil 4. The intermediate is thermally decomposed on the substrate 6 to deposit a compound semiconductor film. The remaining gas is evacuated through a vacuum pump 8.
The present invention applies the selective crystal growth method to the above mentioned MOCVD method. First, for better understanding of the present invention, the outline of the selective crystal growth method is to be described.
The selective crystal growth method is a method, in which a monocrystal is permitted to grow originating from a single nucleus formed on a nucleation surface provided on a non-nucleation surface (namely the surface with smaller nucleation density) which has sufficiently larger nucleation density than the non-nucleation surface and a fine surface area to the extent that only a single nucleaus can be generated. Thus, in this method, growth of crystal on the non-nucleation surface, is depressed and growth of a monocrystal occurs only on the nucleation surface.
FIG. 2 is a diagram of steps showing an example of the steps of the method of forming a crystal of a compound semiconductor according to the selective nucleation method of the present invention.
First, on a substrate 9 comprising high melting glass, quartz, alumina, ceramic, etc. which can stand high temperature, a SiO 2 film 10 is deposited to about 1000 Å according to the conventional chemical vapor deposition method (CVD method) by use of, for example, silane (SiH 4 ) and oxygen (O 2 ) Formation of Substrate!. Nucleation density (NDs) of the group II-VI compound semiconductor on SiO 2 film 10 is small, and the SiO 2 film 10 provides the non-nucleation surface (S NDS ). The above non-nucleation surface (S NDS ) may be formed by the physical vapor deposition (PVD) method such as vapor deposition method, sputtering method, etc.
In the case where the surface of the substrate 9 is constituted of material providing a non-nucleation surface (S NDS ), it is possible to use only the substrate 9 as it is without providing a SiO 2 film, etc. thereon.
Next, the surface of the SiO 2 film 10 is masked to a desired pattern with a photoresist 11.
Ions 12 of an element selected from among the group IV, the group II, and the group VI elements are implanted by use of an ion implanter.
The ions 12 are implanted onto the exposed SiO 2 film surface (FIGS. 2(C) and 2(D)). The amount of ions implanted may be determined depending on the desired characteristics, but should be preferably 1×10 15 cm -2 or more, more preferably 5×10 15 cm -2 or more, and most preferably 1×10 16 -2×10 16 cm -2 . Preferred elements implanted as ions 12 include Si, Ge, Zn, Cd, S and Se. Nucleation density (NDs) of the group II-VI compound semiconductor on the surface where no ion is implanted is small, and this portion becomes the non-nucleation surface (S NDS ). On the other hand, the regions 13-1, 13-2 where ions are implanted have larger nucleation density (ND L ) than the non-nucleation surface (S NDS ), and this portion becomes the nucleation surface (S NDL ). At this time, the size of the ion implanted portion is generally some μm or less, preferably 2 μm or less, and most preferably 1 μm or less.
After the photoresist 11 is removed and the substrate (the support 9 provided with the SiO 2 film 10 on the surface thereof) is washed, an organometallic material represented by the general formula R 1 --X n --R 2 , which is the group VI element supplying starting material, is supplied to form a compound semiconductor material film on a substrate. In the present application, the organometallic compound represented by the general formula R 1 --X n --R 2 as the group VI element supplying starting material may be suitably selected depending on the desired characteristics, but should be preferably the compounds wherein n is 2-4 and R 1 and R 2 each represent methyl or ethyl. Preferred organometallic compounds (VI) represented by the general formula R 1 --X n --R 2 include the following:
dimethyl disulfide CH 3 --S--S--CH 3
diethyl disulfide C 2 H 5 --S--S--C 2 H 5
dimethyl trisulfide CH 3 --S--S--S--CH 3
diethyl trisulfide C 2 H 5 --S--S--S--C 2 H 5
dimethyl diselenide CH 3 --Se--Se--CH 3
diethyl diselenide C 2 H 5 --Se--Se--C 2 H 5
dimethyl triselenide CH 3 --Se--Se--Se--CH 3
diethyl triselenide C 2 H 5 --Se--Se--Se--C 2 H 5
t-butylethyl disulfide t-C 4 H 9 --S--S--C 2 H 5
dipropyl disulfide C 3 H 7 --S--S--C 3 H 7
dimethyl ditelluride CH 3 --Te--Te--CH 3
diethyl ditelluride C 2 H 5 --Te--Te--C 2 H 5
Preferred examples of the compound (II) which is the group (II) atoms supplying starting material include organometallic compounds such as dimethylzinc Zn(CH 3 ) 2 ! diethylzinc Zn(C 2 H 2 !, dimethylcadium Cd(CH 3 ) 2 !, diethylcadmium Cd(C 2 H 5 ) 2 !, etc.
The film forming conditions in the method of forming a group II-VI compound semiconductor film of the present invention may be suitably determined. However, the substrate temperature should preferably be 300°-600° C., more preferably 300°-550° C., and most preferably 400°-500° C., and the reaction pressure should be preferably 1-400 torr, more preferably 10-300 torr, and most preferably 50-100 torr. Especially, when a ZnSe compound semiconductor film is formed, a reaction pressure within the range of 10-300 torr is preferred.
FIG. 3 is a graph showing the relationship between the monocrystal ratio (number of monocrystalline islands/(number of monocrystalline islands+number of polycrystalline islands)) and the surface area of nucleation surface when dimethylzinc (CH 3 ) 2 Zn is used as Zn supplying starting material and dimethyl selenide (CH 3 ) 2 Se Reference Example! or dimethyl diselenide (CH 3 ) 2 Se 2 Example of Present Invention! is used as Se supplying material. As shown in FIG. 3, when dimethyl selenium is used, the monocrystal ratio will be remarkably lowered as the nucleation surface becomes larger. Here, the word "polycrystal" is intended to mean the crystal grown until two or more monocrystals are contacted with grain boundaries formed therebetween.
More specifically, in judging whether the obtained crystal is polycrystalline or not, those crystals through which two or more grain boundaries run when observed through the upper surface of the crystal by a SEM are defined as polycrystals.
In the above example and reference example, the crystal forming time was 30 minutes; the nucleation surface distance was 100 μm; the molar ratio (VI/II) of the group VI element supplying starting material and the group II element supplying starting material was 1:5; the substrate temperature was 500° C.; and the inner pressure was 120 Torr.
As can be seen in FIG. 3, the monocrystal ratio is higher when dimethyl diselenide is used as the group VI element supplying starting material (present invention).
The present invention is further illustrated by the following examples but it is to be understood that the scope of the invention is not to be limited thereby.
EXAMPLE 1
Crystal forming treatment was carried out by the apparatus shown in FIG. 1 in accordance with the steps as shown in FIG. 2. In the surface of a support 9 constituted of quartz, a SiO 2 film 10 was deposited to a film thickness of 1000 Å under the following conditions:
Flow rate ratio of starting gases (molar ratio): SiH 4 :O 2 =3:1.7
Pressure: 1 atm
Support temperature: 400° C.
Next, on the surface of the SiO 2 film 10 was provided a photoresist (trade name OSTR-800, manufactured by Tokyo Ohka.) Following the conventional method and procedure, the photoresist 11 was subjected to patterning treatment to provide 20×20 holes of 1 μm square with an interval of 50 μm. Next, by use of an ion implanter (trade name: CS 3000, manufactured by VARIAN Corp.), Se 2- ions of 1×10 15 cm -2 were implanted to form the regions 13-1 and 13-2 see FIG. 2(C)!.
After the photoresist 11 remaining on the SiO 2 film 10 was peeled off, the support was subjected to heat treatment in PCl 3 atmosphere at about 550° C. for 10 minutes to clean the surface of the SiO 2 film 10.
Subsequently, while the support was heated to 500° C., dimethylzinc (CH 3 ) 2 Zn together with dimethyl diselenide (H 3 C--Se--Se--CH 3 ), and further HCl were flowed onto the support surface at a molar ratio of 1:8:0.2 together with a carrier gas H 2 , thereby permitting ZnSe monocrystals to grow FIGS. 2(E) and 2(F)!. The reaction pressure at this time was made 100 Torr.
The chemical reaction at the time of formation of ZnSe crystal in the present invention is hypothesized as follows. That is, the starting gases are mixed near the blowing outlet 3 shown in FIG. 1 to cause chemical reaction, thereby forming a stable intermediate as shown below, which is then delivered to the surface of the SiO 2 film 10 on the support to be thermally decomposed.
H.sub.3 C--Zn--CH.sub.3 +H.sub.3 C--Se--Se--CH.sub.3 →H.sub.3 C--Se--Zn--Se--CH.sub.3 (intermediate)+C.sub.2 H.sub.6 .Arrow-up bold.
At that time, as shown in FIG. 2(E), ZnSe monocrystals 14-1, 14-2 grow only on the nucleation surface 13-1, 13-2 where Se 2- ions have been implanted, and no ZnSe crystal is formed on the SiO 2 film surface where no Se 2- ion has been implanted.
When growth of the ZnSe monocrystal 14-1, 14-2, is further continued, ZnSe crystals 14-1 and 14-2 come into contact with each other as shown in FIG. 2(F). At that stage, the crystal growth treatment was stopped and the surface portions of the ZnSe monocrystals 14-1, 14-2 were polished and the portions of the crystal grain boundary 15 was etched (FIG. 2(G)). Thus ZnSe monocrystals 16-1, 16-2 were obtained.
EXAMPLE 2
Crystal growth treatment was carried out by use of the apparatus schematically shown in FIG. 1 in accordance with the steps shown in FIGS. 4(A)-4(D) which show the ZnS crystal forming steps.
First, on an alumina support 17, a SiO 2 film 18 was deposited to a thickness of 2000 Å similarly as in Example 1 by use of SiH 4 and O 2 as the starting materials by the thermal CVD method. Next, according to the plasma CVD method using SiH 4 and NH 3 as the starting gases, a SiN x film was deposited to a thickness of 300 Å on the SiO 2 film 18. The supplying ratio of SiH 4 and NH 3 was 2:1; the reaction pressure was 0.15 Torr; and the high frequency output power was 1.6×10 -2 W/cm 2 . The SiN x film was then subjected to patterning treatment to form 20×20 nucleation surfaces 19-1, 19-2 having a surface area of 1 μm square (See FIG. 4(A)) Formation of substrate to be subjected to crystal forming treatment!. After the substrate was well washed, it was subjected to heat treatment in H 2 atmosphere at about 900° C. for 10 minutes. Next, while heating the substrate to 550° C., dimethylzinc (H 3 C--Zn--CH 3 ) and dimethyl disulfide (H 3 C--S--S--CH 3 ) were supplied at a molar ratio of 1:20 together with carrier gas H 2 to permit ZnS monocrystals 20-1, 20-2 to grow. The reaction pressure at this time was 150 Torr. As shown in FIG. 4(B), ZnS crystals 20-1, 20-2 were grown only from the nucleation srufaces of a SiN x film 19-1, 19-2, while no ZnS nucleus was generated on the SiO 2 surface as the non-nucleation surface. When the ZnS monocrystals 20-1, 20-2 were further permitted to grow, ZnS monocrystals 20-1 and 20-2 came into contact with each other as shown in FIG. 4(C). At that stage, the crystal forming treatment was stopped. The surface portions of the ZnS monocrystals 20-1, 20-2 were then polished and the crystal grain boundary 15 was removed by etching to obtain ZnS monocrystals 20-1, 20-2 as shown in FIG. 4(D). The ZnS monocrystals 20-1, 20-2 thus obtained were confirmed to have very good crystallinity and to be execellent in semiconductor characteristics. | A method of forming a crystalline compound semiconductor film comprises introducing into a crystal forming space housing a substrate on which a non-nucleation surface (S NDS ) having a smaller nucleation density and a nucleation surface (S NDL ) having a fine surface area sufficient for crystal growth only from a single nucleus and having a larger nucleation density (ND L ) than the nucleation density (NDs) of the non-nucleation surface (S NDS ) are arranged adjacent to each other an organometallic compound (VI) for supplying an element belonging to the group VI of Periodic Table represented by the general formula R 1 --X n --R 2 wherein n is an integer of 2 or more; R 1 and R 2 each represent alkyl; and X is S, Se or Te and a compound (II) for supplying an element belonging to the group II of Periodic Table in gas phase and applying crystal growth treatment according to the vapor phase method to the substrate to selectively form a crystalline group II-VI compound semiconductor film on the substrate. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a content output apparatus, a content output method, and a recording medium.
[0003] 2. Description of the Related Art
[0004] JP 2011-150221 A discloses a display device that performs various kinds of notice by projecting a human image onto a flat screen having a human shape in order to give impressive notice to viewers. Further, a technique for projecting a human image onto a three-dimensional screen has been studied to give more realistic impression to viewers.
[0005] However, in display devices known to the inventors, it is difficult to change contents depending on a language used by a viewer.
[0006] In view of this, an object of the present invention is to output a content in an appropriate language for a viewer.
SUMMARY OF THE INVENTION
[0007] According to an embodiment of the present invention, there is provided a content output apparatus including: an acquisition unit configured to acquire, from a communication partner terminal, language information used by the communication partner terminal; and an output unit configured to output a content on the basis of the language information.
BRIEF DESCRIPTION OF THE DRAWING
[0008] FIG. 1 shows a configuration of a content output system according to this embodiment;
[0009] FIG. 2 is a block diagram of a configuration of a digital signage device according to this embodiment;
[0010] FIG. 3 is a block diagram of a configuration of a terminal device according to this embodiment;
[0011] FIG. 4 shows a sequence of wireless communication according to this embodiment;
[0012] FIG. 5 is a flowchart of content output processing of the digital signage device according to this embodiment; and
[0013] FIG. 6 is a flowchart of content output processing of the terminal device according to this embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] Hereinafter, a wireless communication device according to an embodiment of the present invention will be described with reference to the drawings. Note that the same or corresponding parts are denoted by the same reference signs.
[0015] FIG. 1 shows a configuration of a content output system according to this embodiment. In a configuration example of FIG. 1 , the content output system includes a digital signage device 1 and a terminal device 2 that performs wireless communication with the digital signage device 1 . The digital signage device 1 and the terminal device 2 perform wireless communication with each other on the basis of, for example, Bluetooth (registered trademark) low energy (hereinafter, referred to as BLE.). The BLE is a standard (mode) developed for the purpose of low power consumption in a short-range wireless communication standard referred to as Bluetooth (registered trademark).
[0016] The digital signage device 1 is, for example, a projection device that irradiates a screen (not shown) with the use of a rear projection projector, is provided on a store, an exhibition hall, and the like, and reproduces contents such as explanation of products, guidance, and questionnaires. The terminal device 2 is, for example, a smartphone or a tablet personal computer.
[0017] As shown in FIG. 2 , the digital signage device 1 includes a controller 11 , a display unit 12 , an input unit 13 , a communication unit 14 , and a storage unit 15 , and the storage unit 15 includes an image data storage unit 151 and an audio data storage unit 152 .
[0018] The controller 11 is constituted by a Central Processing Unit (CPU) and the like and includes the CPU that executes various programs stored in the storage unit 15 to perform predetermined calculation and control each unit and a memory serving as a working area when the programs are executed (both are not shown).
[0019] The display unit 12 is a projector that converts image data output from the controller 11 into projected light to irradiate a screen with the projected light.
[0020] For example, as a projector, it is possible to apply a Digital Light Processing (DLP) (registered trademark) projector including a digital micromirror device (DMD) which is a display element that performs display operation by turning on/off individual inclination angles of a plurality of (in the case of XGA, horizontal 1024 pixels×vertical 768 pixels) micromirrors arranged in an array at a high speed and forms an optical image with the use of reflected light thereof.
[0021] The input unit 13 accepts content change operation and the like from a user. The communication unit 14 transmits and receives a radio signal based on the BLE via an antenna (not shown). The communication unit 14 broadcasts a Beacon (advertise) based on the BLE, receives a connection request transmitted from the terminal device 2 in response to the Beacon, then establishes connection, and receives language information from the terminal device 2 .
[0022] The storage unit 15 includes the image data storage unit 151 storing image data to be projected and the audio data storage unit 152 storing audio data to be output in accordance with the image data. The audio data storage unit 152 stores a plurality of pieces of audio data of languages in various countries, such as Japanese, English, and Chinese, corresponding to image data.
[0023] FIG. 3 is a block diagram of a configuration of the terminal device 2 . The terminal device 2 includes a controller 21 , a display unit 22 , an input unit 23 , a communication unit 24 , and a storage unit 25 , and the storage unit 25 includes a language information storage unit 251 .
[0024] The controller 21 is constituted by a Central Processing Unit (CPU) and the like and includes the CPU that executes various programs stored in the storage unit 25 to perform predetermined calculation and control each unit and a memory serving as a working area when the programs are executed (both are not shown).
[0025] The display unit 22 includes, for example, a Liquid Crystal Display (LCD) or an Electroluminescence (EL) display.
[0026] The input unit 23 is, for example, a touchscreen, is provided on the display unit 22 , and is an interface used for inputting content of operation performed by a user. The touchscreen includes, for example, a transparent electrode (not shown). In the case where a finger or the like of a user is touched, the touchscreen detects a position where a voltage is changed as a touch position and outputs information on the touch position to the controller 21 as an input instruction.
[0027] The storage unit 25 includes the language information storage unit 251 storing language information used by a user.
[0028] FIG. 4 shows a sequence of wireless communication for acquiring language information according to this embodiment.
[0029] First, the digital signage device 1 broadcasts a Beacon with the use of the communication unit 14 (Step S 41 ). The Beacon contains identification information of the digital signage device 1 .
[0030] Then, the terminal device 2 that has received the broadcasted Beacon specifies the digital signage device 1 on the basis of the identification information contained in the Beacon and transmits a connection request to the digital signage device 1 (Step S 42 ).
[0031] The digital signage device 1 that has received the connection request establishes communication with the terminal device 2 , and the terminal device 2 acquires used language information from the language information storage unit 251 and transmits the language information to the digital signage device 1 (Step S 43 ).
[0032] FIG. 5 is a flowchart of content output processing of the digital signage device 1 . The digital signage device 1 refers to the image data storage unit 151 and projects a content. The digital signage device 1 acquires audio corresponding to the content from the audio data storage unit 152 and reproduces the audio.
[0033] First, the digital signage device 1 broadcasts a Beacon (Step S 51 ). The digital signage device 1 determines whether or not a connection request has been received from the terminal device 2 in response to the Beacon broadcasted in Step S 51 (Step S 52 ).
[0034] In the case where the connection request has not been received (Step S 52 NO), the processing returns to Step S 51 and the digital signage device 1 broadcasts a Beacon again. In the case where the connection request has been received (Step S 52 Yes), the digital signage device 1 establishes connection with the terminal device 2 (Step S 53 ).
[0035] After connection with the terminal device 2 is established, the digital signage device 1 determines whether or not language information has been received from the terminal device 2 (Step S 54 ). In the case where it is determined that the language information has not been received (Step S 54 NO), Step S 54 is repeated until the language information is received.
[0036] In the case where the language information has been received (Step S 54 YES), the digital signage device 1 compares language information of audio that is currently reproduced with the language information transmitted from the terminal device and determines whether or not those pieces of language information match with each other.
[0037] In the case where those pieces of language information match, reproduction is continued. In the case where it is determined that those pieces of language information do not match, the processing proceeds to Step S 56 , and the digital signage device 1 changes the language by referring to the audio data storage unit 152 to acquire audio data matching with the language information transmitted from the terminal device and reproducing the audio data.
[0038] FIG. 6 is a flowchart of content output processing of the terminal device 2 according to this embodiment.
[0039] The terminal device 2 determines whether or not a Beacon has been received from the digital signage device 1 (Step S 61 ). In the case where it is determined that the Beacon has not been received (Step S 61 NO), Step S 61 is repeated until the Beacon is received.
[0040] In the case where it is determined that the Beacon has been received in Step S 61 , the terminal device 2 specifies the digital signage device 1 that has transmitted the Beacon on the basis of identification information contained in the Beacon, transmits a connection request to the digital signage device 1 (Step S 62 ), and establishes connection with the digital signage device 1 .
[0041] After transmitting the connection request to the digital signage device 1 , the terminal device 2 refers to the language information storage unit 251 to acquire a language set as a used language. After the used language is acquired, the terminal device 2 transmits language information on the used language to the digital signage device 1 (Step S 63 ).
[0042] As described above, in this embodiment, the digital signage device 1 changes a language by acquiring language information from the terminal device 2 . Therefore, it is possible to reproduce a content suitable for each user.
[0043] In this embodiment, only audio data is changed and image data is not changed. However, this embodiment is not limited thereto, and moving image data in which image data and audio data are integrated may be changed.
[0044] In the case where there is no audio data matching with language information acquired from the terminal device 2 , audio data may be changed to audio data of a language which is likely to be understood, i.e., audio data may be set to, for example, English.
[0045] The embodiment described above is presented merely as an example and does not intend to limit the gist of the invention. The above new embodiment can be implemented in other various forms, and various kinds of omission, replacement, and modification can be performed within the scope of the invention. Those embodiments and modification thereof are encompassed in the scope or the gist of the invention and are also encompassed in the scope of the inventions described in claims and equivalents thereof. | Provided is a content output apparatus including: an acquisition unit configured to acquire, from a communication partner terminal, language information used by the communication partner terminal; and an output unit configured to output a content on the basis of the language information. | 7 |
FIELD OF THE INVENTION
The present invention relates to the detection of lens aberrations associated with the projection lens utilized in a lithography system and more particularly to the design, layout and application of lens-aberration monitoring structures that can be used to monitor the projection lens performance during the manufacture of semiconductor devices.
BACKGROUND OF THE INVENTION
Lithographic apparatus may employ various types of projection radiation, non-limiting examples of which include ultra-violet light (“UV”) radiation (including extreme UV (“EUV”), deep UV (“DUV”), and vacuum UV (“VUV”)), X-rays, ion beams or electron beams. Depending on the type of radiation used and the particular design requirements of the apparatus, the projection system may be for example, refractive, reflective or catadioptric, and may comprise vitreous components, grazing-incidence mirrors, selective multi-layer coatings, magnetic and/or electrostatic field lenses, etc; for simplicity, such components may be loosely referred to in this text, either singly or collectively, as a “lens”.
In a manufacturing process using such a lithographic projection apparatus, a pattern in a mask is imaged onto a substrate which is at least partially covered by a layer of radiation-sensitive material (resist). Prior to this imaging step, the substrate may undergo various procedures, such as priming, resist coating and a soft bake. After exposure, the substrate may be subjected to other procedures, such as a post-exposure bake (PEB), development, a hard bake and measurement/inspection of the images features. This array of procedures is used as a basis to pattern an individual layer of a device, e.g., an integrated circuit (IC). Such a patterned layer may then undergo various processes such as etching, ion-implantation (doping), metallization, oxidation, chemo-mechanical polishing, etc., all intended to finish off an individual layer. If several layers are required, then the whole procedure, or a variant thereof, will have to be repeated for each new layer. Eventually, an array of devices will be present on the substrate (wafer). These devices are then separated from one another by a technique such as dicing or sawing, whence the individual devices can be mounted on a carrier, connected to pins, etc. Further information regarding such processes may be obtained, for example, from the book “Microchip Fabrication: A Practical Guide to Semiconductor Processing”, Third Edition, by Peter van Zant, McGraw Hill Publishing Co., 1997 ISBN 0-07-067250-4.
The current state of integrated circuit (IC) fabrication requires lithography processes to provide for patterning feature line widths to near one-half of the exposure wavelength. For the 150 nm device generation, the krypton fluoride (KrF) excimer laser (248 nm) is typically selected as the exposure source of choice. Recent research and development efforts have further demonstrated the possibility of utilizing the KrF excimer laser for the 130 nm device generation. This is achieved by combining the use of multiple resolution enhancement techniques (RET), such as, attenuated phase-shifting masks (attPSM) and off-axis illumination (OAI), in combination with optical proximity correction (OPC) techniques. One possible alternative to the foregoing techniques is to use a shorter exposure wavelength, for example, an argon fluoride (ArF) excimer laser having a wavelength of 193 nm. However, due to various complications associated with the use of the ArF excimer laser, it is likely that the KrF excimer laser will be the dominant laser of choice for fabricating the 130 nm device generation.
Regardless of the excimer laser utilized in the fabrication process, the fabrication of devices having critical dimensions of 150 nm or less requires that the near-diffraction-limited lens utilized in the fabrication process be substantially aberration free. As is known, aberrations can be caused by various sources, such as a defective lens or an aging laser which emits a beam having a frequency shifted from the desired value. Accordingly, it is desirable to verify lens performance (i.e., qualify the lens) prior to installation, and then to subsequently monitor the lens performance during use (e.g., in an IC fabrication process).
During the lens manufacturing process, the lens performance can be fully tested interferometrically. Typically, the lens is first qualified at the factory and then again during the initial installation in the field. One common practice utilized for lens qualification is to print wafers and then measure the dimensions of the minimum feature width, or the critical dimension (CD). During this qualification process, both “vertical” and “horizontal” features are measured (i.e., features extending in two orthogonal directions on the substrate plane). In some instances, the CD for 45-degree features is also measured. In order to verify lens performance, a sufficient number of CD measurements are required across the entire exposure field. The results of the CD measurements are then analyzed to determine whether or not the lens performance is acceptable.
Although the CD measurement method provides a method of evaluating the performance of the lens, it is not a simple task to correlate the CD data to the “signature” of the lens aberration. Accordingly, there have been efforts to perform a direct observation of lens aberrations. For example, an article by Toh et al. entitled “Identifying and Monitoring of Lens Aberrations in Projection Printing,” SPIE Vol. 772, pp. 202-209 (1987) described methods for measuring the effects of relatively large lens aberrations of about 0.2λ, where λ is the exposure wavelength. However, for today's near-diffraction-limited optics, any lens aberration is likely to be in the neighborhood of 0.05λ, or smaller. For 130 nm features, a 0.05λ lens aberration translates to a 12.4 nm dimensional error when utilizing the KrF exposure source. Accordingly, if the feature CD budget (i.e., error tolerance) is assumed to be ±10% of the target feature width, a 12.4 nm error consumes almost the entire CD budget.
In an article by Gortych et al. entitled “Effects of Higher-Order Aberrations on the Process Window,” SPIE Vol. 1463, pp. 368-381 (1991) it was demonstrated that higher-order lens aberrations could deteriorate lithographic process windows. Unfortunately, the higher-order lens aberrations are difficult to eliminate after the photolithography system is assembled. In an article by Brunner entitled “Impact of Lens Aberration on Optical Lithography,” INTERFACE 1996 Proceedings, pp. 1-27 (1996) simulation was utilized to demonstrate the negative impact of near-wavelength features due to several first-order lens aberrations. Specifically, it was possible to observe coma aberrations by examining how the contact features were printed when utilizing attenuated PSM. It is also known that that lens aberrations can be balanced with custom off-axis illumination. Others have attempted to make direct measurements of various kinds of lens aberrations in an effort to achieve better CD control.
An article by Farrar et al. entitled “Measurement of Lens Aberrations Using an In-Situ Interferometer Reticle,” Advanced Reticle Symposium, San Jose, Calif. (June 1999) reported the use of an in-situ interferometer reticle to directly measure lens aberration. According to Farrar, it was possible to derive lens aberrations up to 37 Zernike terms. Although Farrar claims that the method is accurate and repeatable, it involves hundreds or thousands of registration type measurements (i.e., the measuring of the shift in relation to the intended feature position). As such, while Farrar's method may be accurate and repeatable, with the need for such exhaustive measurements, the method is clearly very time consuming, and therefore likely unusable in a manufacturing-driven environment. Furthermore, it is conceivable that minute lens aberrations can drift over time due to various reasons (e.g., as a result of the periodic preventive maintenance performed on a system). Thus, as it is critical to monitor lens performance on a periodic basis, the use of Farrar's method, which requires substantial measurements and calculations, is impractical. Accordingly, there is a need to be able to monitor the lens aberration directly from the printed product wafers.
In an effort to accomplish this objective, in 1999 Dirksen et al. (see, U.S. Pat. No. 6,248,486, filed Sep. 29, 1999, incorporated herein by reference) proposed a method for directly monitoring lens aberration from the printed wafers. According to Dirksen's method, the lens monitor comprises simple circular features on the reticle. More specifically, the circular feature is a chromeless feature that has been etched into the glass substrate of the reticle. The etched depth is typically λ/2 and the diameter is about (λ/NA), where NA is the numerical aperture of the projection lens. According to Dirksen, the method has proven to be effective. Further, the structure is simple and small enough to be readily placed throughout the entire exposure field.
Still, there are a number of issues concerning the use of Dirksen's lens aberration monitor. First, the depth of the lens monitor feature on the mask needs to be etched to approximately half of the wavelength. For a special-purpose mask, there is no problem dedicating an extra (or special) mask making process step to fabricate such a feature. However, for production reticle types, such as a binary chrome reticle or attPSM, an extra mask making process step necessary to create such a monitor is costly and time-consuming process. Alternating PSM (altPSM) or chromeless PSM (CLM) would also require the extra mask making process step. Further, since the Dirksen monitor calls for a different etch depth in the quartz substrate as opposed to the π-phase, it requires a special etch time and must be done separately.
A second issue with Dirksen's lens monitor is that it is vulnerable to phase error that may result from the quartz etch process during mask formation. More specifically, referring to FIGS. 1 ( a )- 1 ( f ), for an exacerbated phase error, the quartz etch process causes a sloped edge profile on the mask as shown in FIG. 1 ( a ). In such a case, the Dirksen monitor loses all of the sensitivity to indicate any possible lens aberration. However, when there is no phase-error on the mask, as shown in FIG. 1 ( d ), the Dirksen monitor is effective for detecting lens aberrations. FIGS. 1 ( b ) and 1 ( e ) illustrate a cross-sectional view of the printed resist pattern resulting from the “sloped” Dirksen monitor structure of FIG. 1 ( a ) and the “ideal” Dirksen monitor structure of FIG. 1 ( d ), respectively.
It is noted that the printing conditions utilized to produce the resist profiles illustrated in FIGS. 1 ( b ) and 1 ( e ) were as follows: a 0.68 NA with 0.8 partial coherence at +0.1 μm de-focus, utilizing a Shipley UV6 resist with a thickness of 0.4 μm on an organic BARC (AR2) on top of a polysilicon wafer. The simulation introduced a +0.025λ coma for both X & Y (Z7 and Z8 of Zernike terms).
Upon a closer examination of the ring-shaped resist patterns formed by the Dirksen monitor structures, as shown for example in FIGS. 1 ( c ) and 1 ( f ), it is clear that the inner ring of the printed resist pattern has a relatively sloppy resist profile in contrast to the steep profile formed by the outer ring structure. The reason for this variation is that the outer-ring resist pattern is formed by the phase change in the mask, while the inner ring resist pattern is formed without any such phase change. Specifically, the inner ring resist pattern is formed via the attenuation of the exposure wavelength that is passed through the center of the Dirksen monitor pattern. In other words, the two resist profiles (i.e., the inner ring and the outer ring) are formed by two inherently different log-slopes of the respective aerial images. The difference in resist profiles can lead to erroneous registration measurements, which can cause a misinterpretation of the lens aberration in question.
It is noted that it is possible to observe a slight coma with the Dirksen lens aberration monitor, as shown in FIGS. 1 ( e ) and ( f ). Specifically, the width of the ring is different on the left side as compared to the right side. It is further noted that it is difficult to observe this coma in the “sloped” Dirksen monitor, as shown in FIGS. 1 ( b ) and 1 ( c ).
Accordingly, in view of the foregoing problems, there remains a need for a lens monitor that allows for the detection of lens aberrations, but which is not easily impaired by slight imperfections in the mask making process. It is also desirable that the lens monitor structures be small enough such that they can be positioned in numerous places between or beside production die for in-situ lens monitoring purposes. It is also desirable that the lens monitor can be fabricated without requiring extra mask making process steps.
SUMMARY OF THE INVENTION
In an effort to solve the aforementioned needs, it is an object of the present invention to provide a lens monitor capable of detecting lens aberrations, where the lens monitor structures are sufficiently small in size so as to allow the monitor to be utilized for in-situ production monitoring, and which monitor does not require extra processing steps during mask formation. In addition, the functionality of the lens monitor should not be significantly impaired by minor imperfections in the mask formation process.
More specifically, the present invention relates to a lens aberration monitor for detecting lens aberrations. The lens aberration monitor comprises a mask for transferring a lithographic pattern onto a substrate, and a plurality of non-resolvable features disposed on the mask. The plurality of non-resolvable features are arranged so as to form a predetermined pattern on the substrate. The predetermined pattern is then utilized to detect lens aberrations. The size of the monitor is such that the mask can also contain a lithographic pattern corresponding to a device (e.g., an integrated circuit) to be formed on the substrate.
The present invention also relates to a method of detecting aberrations associated with a projection lens utilized in an optical lithography system. The method comprises the steps of forming a mask for transferring a lithographic pattern onto a substrate, forming a plurality of non-resolvable features disposed on the mask, where the plurality of non-resolvable features are arranged so as to form a predetermined pattern on the substrate, imaging the mask using the optical lithography system so as to print the mask on the substrate, and analyzing the position of the predetermined pattern formed on the substrate and the position of the plurality of non-resolvable features disposed on the mask so as to determine if there is an aberration. As explained below, if the position of the predetermined pattern differs from an expected position, which is determined from the position of the plurality of non-resolvable features, this shift from the expected position indicates the presence of an aberration.
As described in further detail below, the present invention provides significant advantages over the prior art. Most importantly, the present invention provides a lens monitor capable of detecting very subtle lens aberrations, and is substantially immune to deficiencies in the masking formation process utilized to form the monitor.
In addition, the lens monitor of the present invention is suitable for in-situ monitoring, as the lens monitor can be formed utilizing the same mask formation process required to form the production mask, and therefore does not require any additional mask formation processing steps. Furthermore, as the overall size of the lens monitor structures are sufficiently small, the monitor structures can be positioned in a sufficient number of positions in so as to allow for monitoring of the entire exposure field.
Yet another advantage is that the effectiveness of the lens monitor is relatively insensitive to both of the “sloped” phase edges and the “corner rounding” effects that are inherent to mask making process.
Additional advantages of the present invention will become apparent to those skilled in the art from the following detailed description of exemplary embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 ( a ) illustrates a top and cross-sectional view of a “sloped” Dirksen lens aberration monitor structure.
FIG. 1 ( b ) illustrates a cross-sectional view of the printed resist pattern resulting from the “sloped” Dirksen lens aberration monitor structure of FIG. 1 ( a ).
FIG. 1 ( c ) illustrates a top view of the resist pattern illustrated in FIG. 1 ( b ).
FIG. 1 ( d ) illustrates a top and cross-sectional view of an “ideal” Dirksen lens aberration monitor structure.
FIG. 1 ( e ) illustrates a cross-sectional view of the printed resist pattern resulting from the “ideal” Dirksen lens aberration monitor structure of FIG. 1 ( d ).
FIG. 1 ( f ) illustrates a top view of the resist pattern illustrated in FIG. 1 ( e ).
FIG. 2 ( a ) illustrates a top and cross-sectional view of a Dirksen monitor structure modified so as to form a ring-like structure.
FIG. 2 ( b ) is a one-dimensional cross-sectional aerial image of the ring-like structure monitor of FIG. 2 ( a ).
FIG. 2 ( c ) is a cross-sectional view of the printed resist pattern resulting from the ring-like monitor structure of FIG. 2 ( a ).
FIG. 3 ( a ) illustrates an exemplary lens aberration monitor structure in accordance with the present invention.
FIGS. 3 ( b )- 3 ( g ) illustrate exemplary variations of the lens aberration monitor structure illustrated in FIG. 3 ( a ) and the printing performance thereof.
FIG. 4 ( a ) illustrates the object phase spectrum produced by the Dirksen monitor structure of FIG. 1 .
FIG. 4 ( b ) illustrates the object phase spectrum produced by the “ring-like” monitor structure of FIG. 2 .
FIG. 4 ( c ) illustrates the object phase spectrum produced by the lens aberration monitor structure illustrated in FIG. 3 ( a ).
FIG. 4 ( d ) illustrates a 1-D cross-sectional aerial image produced by the Dirksen monitor structure of FIG. 1 .
FIG. 4 ( e ) illustrates a 1-D cross-sectional aerial image produced by the “ring-like” monitor structure of FIG. 2 .
FIG. 4 ( f ) illustrates a 1-D cross-sectional aerial image produced by the lens aberration monitor structure of FIG. 3 ( a ).
FIGS. 5 ( a )- 5 ( c ) illustrates the actual printing performance of the lens aberration monitor structure illustrated in FIG. 3 ( a ).
FIG. 6 ( a ) illustrates a top and cross-sectional view of the lens aberration monitor structure of FIG. 3 ( a ), wherein the mask formation process results in the non-resolvable features having sloped edges.
FIG. 6 ( b ) illustrates the object phase spectrum produced by the lens aberration monitor structure illustrated in FIG. 6 ( a ).
FIG. 6 ( c ) illustrates a two-dimensional aerial image of the lens aberration monitor structure illustrated in FIG. 6 ( a ) as projected by the projection lens.
FIG. 6 ( d ) illustrates a top view of the original resist patterns of FIG. 6 ( a ) overlapped with the resulting lens aberration monitor structure printed on a wafer.
FIG. 6 ( e ) is a cross-sectional view of the resulting lens aberration monitor structure corresponding to the monitor structure of FIG. 6 ( a ).
FIGS. 7 ( a )- 7 ( d ) demonstrate the ability of the lens aberration monitor of the present invention to be utilized in conjunction with a 6% attPSM or a binary chrome mask.
FIGS. 8 ( a )- 8 ( h ) illustrate the capability of the lens aberration monitor of the present invention to detect lens aberrations.
The invention itself, together with further objects and advantages, can be better understood by reference to the following detailed description and the accompanying drawings.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description of the lens aberration monitor of the present invention relates to both the lens monitor itself as well as a method of forming the lens aberration monitor. It is noted that in an effort to facilitate the understanding of the present invention, the following description details how the lens monitor can be utilized to form ring-shaped lens monitors structures. However, it is also noted that the present invention is not limited to such ring-shaped lens structures. Clearly, other shapes are possible.
From the observations described above with regard to the Dirksen monitor, the inventors of the present invention initially thought that the resist profile of the inner ring of Dirksen's monitor structure could be improved by modifying the monitor such that it exhibited a ring-like structure. In other words, the degraded/sloppy resist profile of the inner ring of Dirksen's monitor structure could be corrected by creating a phase change at the center of the structure. However, contrary to the initial thoughts, the inventor of the present invention determined that creating a phase change at the center of the Dirksen structure did not result in the corresponding resist profile exhibiting a ring-like structure. Moreover, the resulting resist profile was essentially useless for monitoring lens aberration.
FIGS. 2 ( a )- 2 ( c ) illustrate the Dirksen monitor structure modified to form a ring-like structure. Specifically, FIG. 2 ( a ) illustrates a top and cross-sectional view of the Dirksen structure modified so as to form a ring-like structure. FIG. 2 ( b ) is a one-dimensional cross-sectional aerial image of the ring-like structure of FIG. 2 ( a ). FIG. 2 ( c ) is a cross-sectional view of the printed resist pattern resulting from the ring-like structure of FIG. 2 ( a ). As is clear from a review of FIGS. 2 ( a )- 2 ( c ), the ring-like structure (FIG. 2 ( a )) does not produce a ring-shaped resist profile. This is due to the fact that the aerial image of the monitor structure does not have sufficient contrast to allow for patterning of a “ring like” resist structure. As a result, the structure of FIG. 2 ( a ) is essentially useless for monitoring lens aberrations. It is noted that the foregoing is accurate as long as the diameter of the monitor structure is in the range of λ/NA. For a larger diameter, the ring-like design of FIG. 2 ( a ) would likely print a ring-like resist pattern. However, as the diameter becomes larger than λ/NA, the effectiveness of lens aberration monitoring becomes diminished.
In view of the foregoing, one of the primary objectives of the present invention is to provide a lens aberration monitor having structures with an effective diameter in the range of λ/NA, which produce an aerial image having log-slopes which are steep enough to be sufficiently sensitive to indicate minute lens aberration.
FIG. 3 ( a ) illustrates an exemplary lens aberration monitor structure 10 in accordance with the present invention. As shown, the lens aberration structure 10 , which is referred to as an octad halftone ring (OHR), is a sub-resolution halftoning structure comprising a plurality of sub-resolution features 12 . A detailed discussion of the formation of sub-resolution halftoning structures is set forth in U.S. Pat. application Ser. No. 09/270,052 filed on Mar. 16, 1999, which is hereby incorporated by reference.
In the embodiment illustrated in FIG. 3 ( a ), the overall shape of the sub-resolution halftoning structure 10 is circular, while each of the features 12 exhibits a square shape. It is noted that the aberration monitor structure 10 of the present invention is not limited to such shapes. Clearly, the overall shape of the sub-resolution halftoning structure 10 can be other than circular, and the shape of each feature 12 can be other than square. It is noted that the square-shaped sub-resolution features 12 are likely to become corner rounded in an actual design due to the nature of mask making process.
Referring to FIG. 3 ( a ), the size of the individual features 12 and the spacing between the features 12 are as follows. In an exemplary embodiment, the dimension of each side of the square features is approximately 0.3(λ/NA) or less. It is noted that the mask making resolution limits the minimum size for sub-resolution features 12 . For today's production mask making process, the resolution limit is in the range of approximately 200 nm on a 4×mask. On a 1×wafer scale, this is equivalent to 50 nm. For example, when utilizing a 0.68 NA stepper with a KrF exposure source, the size of each square feature 12 can be approximately 100 nm-120 nm per side. In order to maintain a sufficient halftoning effect, it is preferable that the spacing between each square feature 12 be less than 0.15 (λ/NA). Alternatively, the spacing between each feature 12 should be less than about one-half of the square feature's 12 side dimension. It is noted that, as shown in FIG. 3 ( a ), the foregoing spacing requirements refer to the spacing between adjacent features 12 . It is further noted that, as shown in FIG. 3 ( a ), the staggered offset in the X and Y direction are preferably the same. In other words, the portion of a feature 12 overlapping an adjacent feature in either the X direction or the Y direction is preferably the same. In the current embodiment, the preferred staggered offset is in the range of approximately ¼ to ¾ of the sub-resolution element size. Finally, again referring to FIG. 3 ( a ), it is further noted that the distance between the inner edges of the two opposing features having the greatest distance therebetween, taken along the X direction (i.e., features 12 a , 12 b ) or the Y direction (i.e., features 12 c , 12 d ), is preferably approximately equal to (λ/NA). All dimensions are indicated in 1X wafer scale.
In the embodiment of the lens aberration monitor illustrated in FIG. 3 ( a ), the sub-resolution halftoning structure 10 of the present invention utilizes eight square features 12 arranged in a ring-like format. However, as stated, it is not intended that the present invention be so limited. Clearly, it is possible to generate and utilize a sub-resolution halftoning structure which does not exhibit a ring-like shape. It is also possible to form the sub-resolution halftoning structure utilizing a plurality of sub-resolution features having a total number other than eight, as it possible to utilize features having a shape other than square.
More specifically, although line-like structures (e.g., a pair of parallel lines) can show certain types of lens aberration (e.g., coma), it is desirable to form a “ring-like” structure in order to capture other forms of the lens aberration and their corresponding orientation. Further, because each feature 12 is sub-resolution, the particular shape is not of concern. The size of the feature 12 and halftone spacing is more critical. FIGS. 3 ( b ), 3 ( c ) and 3 ( d ) are examples of various configurations and shapes of the sub-resolution features 12 that can be utilized to form monitor structure. FIGS. 3 ( e ), 3 ( f ) and 3 ( g ) illustrates the actual printing performance of the monitor structures illustrated in FIGS. 3 ( b ), 3 ( c ) and 3 ( d ), respectively. All of the exposures were performed under the same conditions, namely 0.68 NA with annular illumination (0.8 inner sigma and 0.6 outer sigma). In addition, in each example, a 0.05λ of X and Y coma were purposely introduced. For all the three examples, the coma lens aberration can be clearly observed from the printed patterns illustrated in FIGS. 3 ( e ), 3 ( f ) and 3 ( g ).
FIGS. 4 ( a )- 4 ( f ) illustrate a comparison of the object spectrums and the aerial images of the Dirksen monitor structure (FIG. 1 ), the ring-like monitor structure (FIG. 2) and the OHR monitor structure of the present invention (FIG. 3 ( a )). More specifically, referring first to FIG. 4 ( a ), it is shown that the phase object spectrum of the Dirksen monitor is not symmetrical within the ±NA (numerical aperture) limits. Turning to FIG. 4 ( b ), it is shown that the “ring-like” monitor has a symmetrical phase spectrum but the overall phase range is compressed. However, as explained above and illustrated in FIG. 4 ( e ), the “ring-like” monitor structure exhibits insufficient aerial image contrast, and is therefore incapable of printing a ring-like resist pattern.
Turning to FIG. 4 ( c ), it is shown that the OHR monitor 10 exhibits a symmetrical phase spectrum within the ±NA limits, while having a full phase range from 0 to 360 degrees. The aerial image corresponding to the OHR monitor 10 (as shown in FIG. 4 ( f )) appears similar to the aerial image produced by the Dirksen monitor (as shown in FIG. 4 ( d )) when the two are compared at the printing threshold of ≈0.3 to 0.35 intensity levels. However, although it is not readily apparent, at the threshold intensity levels, the log-slopes for inner and outer aerial images are more balanced for the OHR monitor structure 10 . This is indicated by the pair of arrows depicted in both FIG. 4 ( d ) and FIG. 4 ( f ).
FIGS. 5 ( a )- 5 ( c ) illustrate the actual printing performance of the OHR lens monitor structure 10 illustrated in FIG. 3 ( a ). The printing conditions utilized to produce FIGS. 5 ( a )- 5 ( c ) are the same as those described above with regard to FIGS. 1 ( a )- 1 ( f ). FIG. 5 ( a ) illustrates a two-dimensional aerial image of the OHR monitor structure 10 as projected on the projection lens. FIG. 5 ( b ) illustrates a top view of the original resist patterns (i.e., features 12 ) overlapped with the resulting OHR monitor structure (i.e., the OHR monitor structure formed as a result of the printing process). As shown in FIGS. 5 ( a )- 5 ( c ), even very subtle coma aberrations can be easily detected by the monitor.
More specifically, the coma aberration (0.025λ for both Z7 and Z8) introduced in the simulation can be observed in the 2-D aerial image of FIG. 5 ( a ) as well as in FIG. 5 ( b ). Referring to FIG. 5 ( b ), the aberration is indicated by the shift of the inner ring 14 of the printed OHR structure to the upper right. Finally, FIG. 5 ( c ), which is a cross-sectional view of the printed OHR structure, illustrates that the inner portion 16 of the left side of the printed OHR structure (of the given cross-sectional view) is shifted more towards the center than the corresponding inner portion 17 of the right side of the printed OHR structure. Each of the foregoing shifts/variations of the location of the OHR structure indicate the existence of a lens aberration. In the event there was no lens aberration, the inner ring 14 of FIG. 5 ( b ) would be equally spaced from each of the square features 12 utilized to form the OHR monitor structure 10 . In addition, both of the resist patterns 16 , 17 of FIG. 5 ( c ) would be equally spaced from the center.
It is noted that in use, the OHR monitor, which is printed in the scribe line or within the die so as to not interfere with the circuit action, would be measured so as to monitor the actual lens aberration in the corresponding exposure field. The lens aberration is then utilized to compute the necessary corrective action required to minimize the CD error. The corrective action can be accomplished, for example, by varying the mask pattern or by tuning the exposure tool. As described herein, the amount of lens aberration can be determined by measuring the relative ring width or the relative position shift of the inner ring circle in relation to a known reference structure that is not sensitive to lens aberration. Another possible method is by taking a SEM photo of the printed OHR pattern and comparing it to a family of OHR patterns with known lens aberrations. Using statistical analysis, it is possible to determine the magnitude and type of lens aberration with reliable repeatability.
One important point regarding the OHR monitor of the present invention is that the performance of the monitor is not degraded as a result of an imperfect mask making process. More specifically, the OHR monitor does not lose lens-aberration detection sensitivity if the quartz etch results in sloped phase edges on the mask. FIG. 6 ( a ) illustrates a top and cross-sectional view of the OHR monitor structure 10 formed in the mask, wherein the mask formation process results in square features 12 having sloped edges. The sloped edges are a result of an imperfect quartz edge process utilized during formation of the mask. However, referring to FIG. 6 ( b ), it is shown that the sloped quartz phase-edge patterns on the mask do not have a noticeable influence on the object phase spectrum. The total object spectrum phase is only slightly compressed (to about 350 degrees). Such compression may result in a very slight reduction in the sensitivity of the lens aberration detection monitor. More importantly, however, even for such an extreme sloppy phase edge, as shown in FIGS. 6 ( c )- 6 ( e ), there is little impact on the printed resist profiles. Thus, in comparison to Dirksen's monitor, the OHR monitor of the present invention provides a much more versatile monitor. It is noted that the printing conditions utilized to produce FIGS. 6 ( c )- 6 ( e ) are the same as those described above with regard to FIGS. 1 ( a )- 1 ( f ).
As previously stated, it is desirable to utilize the lens aberration monitor of the present invention for in-situ monitoring during the production printing process. In order to accomplish this objective, it is necessary to satisfy the following two requirements:
(1) the lens aberration monitor must be made using the same mask making process, with no additional processing steps; and
(2) the lens aberration monitor structure must be usable and effective when printed under the same exposure conditions as intended for printing of the production patterns.
The OHR monitor of the present invention is capable of meeting both requirements. FIGS. 7 ( a )- 7 ( d ) demonstrate the ability of the OHR monitor of the present invention to be utilized on a 6% attPSM or a binary chrome mask. It is noted that the printing conditions utilized to produce FIGS. 7 ( a )- 7 ( d ) are the same as those described above with regard to FIGS. 1 ( a )- 1 ( f ).
More specifically, FIG. 7 ( a ) illustrates a top view of the resist patterns, which were formed on a 6% attPSM, overlapped with the resulting printed OHR monitor structure. FIG. 7 ( b ) is a cross-sectional view of the printed OHR monitor structure resulting from the resist patterns of FIG. 7 ( a ). FIG. 7 ( c ) illustrates a top view of the resist patterns, which were formed on a binary chrome mask, overlapped with the resulting printed OHR monitor structure. FIG. 7 ( d ) is a cross-sectional view of the printed OHR monitor structure resulting from the resist patterns of FIG. 7 ( c ).
As is clear from FIGS. 7 ( a )- 7 ( d ), both the OHR monitor structure formed utilizing 6% attPSM and the OHR monitor structure formed utilizing the binary chrome mask are capable of detecting minute lens aberrations (e.g., 0.025λ). For example, the inner ring 14 of the resulting OHR monitor structure in both FIGS. 7 ( a ) and 7 ( c ) is shifted in the upper-right direction, in the manner similar to the OHR monitor structure illustrated in FIG. 5 ( b ), thereby effectively detecting the 0.025λ lens aberration introduced in the simulation.
It is noted that in order to ensure that the same exposure levels can be utilized along with the associated product patterns, the dimension of the OHR square elements 12 were re-sized to be ≈0.35(λ/NA) for both 6% attPSM and binary chrome mask application. There was no change for the other OHR design parameters. However, due to the use of a slightly larger square element, it may prove necessary to re-tune the spacing between each square element to best optimize the halftoning effect.
As stated above, the OHR monitor of the present invention is quite versatile. For example, in addition to the detection of coma aberrations, as illustrated above in conjunction with FIGS. 5, 6 and 7 , the OHR monitor is also capable of detecting various other types of lens aberrations. FIGS. 8 ( a )- 8 ( h ) illustrate the capability of the OHR monitor to detect lens aberrations. It is noted that the printing conditions utilized to produce FIGS. 8 ( a )- 8 ( h ) are the same as those described above with regard to FIGS. 1 ( a )- 1 ( f ), except for the lens aberration settings, and all with +0.1 μm de-focus.
FIG. 8 ( a ) illustrates a top view of the resist patterns utilized to form the OHR monitor structure overlapped with the resulting OHR monitor structure printed from a diffraction-limited lens. FIG. 8 ( e ) illustrates the wavefront at the projection lens pupil corresponding to the OHR monitor of FIG. 8 ( a ). As shown, the printed OHR monitor structure indicates that the lens is substantially aberration free, as both the inner ring 14 and the outer ring 15 are in the expected position.
FIG. 8 ( b ) illustrates a top view of the resist patterns of the lens aberration monitor structure printed with a lens aberration of 0.05λ and 45 degree astigmatism, overlapped with the resulting OHR monitor structure. FIG. 8 ( f ) illustrates the wavefront at the projection lens pupil corresponding to the OHR monitor structure of FIG. 8 ( b ). As shown, the printed OHR monitor structure reveals the lens aberration by the elongation of the inner ring 14 about the 45 degree axis.
FIG. 8 ( c ) illustrates a top view of the resist patterns of the lens aberration monitor structure printed with a lens aberration of 0.05λ and X and Y coma (Z7 and Z8), overlapped with the resulting OHR monitor structure. FIG. 8 ( g ) illustrates the wavefront at the projection lens pupil corresponding to the OHR monitor structure of FIG. 8 ( c ). As shown, the printed OHR monitor structure indicates the lens aberration by the shifting of both the inner ring 14 and the outer ring 15 in both the upward and right directions.
FIG. 8 ( d ) illustrates a top view of the resist patterns of the lens aberration monitor structure printed with a lens aberration of 0.05λ and X and Y tilt (Z2 and Z3), overlapped with the resulting OHR monitor structure. FIG. 8 ( h ) illustrates the wavefront at the projection lens pupil corresponding to the OHR monitor structure of FIG. 8 ( d ). As shown, the printed OHR monitor structure indicates the lens aberration by the shifting of both the inner ring 14 and the outer ring 15 in both the downward and left directions.
Accordingly, even though actual lens aberrations can be very complicated and subtle, by the combined use of the OHR monitor of the present invention and state-of-the-art metrology tools, it is possible to analyze the underlying cause of lens aberrations. It is noted that the lens aberrations identified above in conjunction with FIGS. 8 ( a )- 8 ( h ) are also apparent when viewing the wavefronts projected on the projection lens pupil as illustrated in FIGS. 8 ( f )- 8 ( h ).
As mentioned above, variations of the exemplary embodiment of the OHR monitor of the present invention are possible. For example, while the exemplary OHR monitor structure is formed in the shape of a ring, clearly other shapes are possible. In addition, the individual features utilized to form the OHR monitor structure may be formed in a shape other than a square.
Furthermore, the OHR can be utilized in all types of mask, for example, binary chrome, attPSM, alternating PSM, and chrome-less PSM. Since the OHR design indicates that such structure and feature spacing can be very sensitive to lens aberration, the OHR design dimensions can be used as a reference for the “forbidden” design rule for integrated circuit design. As such, the circuit features can become less sensitive to minute lens aberrations. This can be extremely important for memory circuit or library circuit design, with the result being enhanced/improved CD control.
Finally, it is also noted that although specific reference may be made in the foregoing description to the use of lithographic projection apparatus in the manufacture of integrated circuits, it should be explicitly understood that such apparatus has many other possible applications. For example, it may be employed in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, liquid-crystal display panels, thin-film magnetic heads, etc. The skilled artisan will appreciated that, in the context of such alternative applications, any use of the terms “reticle” or “wafer” in this text should be considered as being replaced by the more general terms “mask” or “substrate”, respectively.
As described above, the OHR monitor of the present invention provides important advantages over the prior art. Most importantly, the present invention provides a lens monitor which is capable of detecting very subtle lens aberrations, and which is substantially immune to deficiencies in the masking formation process utilized to form the monitor.
In addition, the lens aberration monitor of the present invention is suitable for in-situ monitoring, as the lens monitor can be formed utilizing the same mask formation process required to form the production mask, and therefore does not require any additional mask formation processing steps. Furthermore, as the overall size of the lens monitor structure is sufficiently small, the structure can be positioned in a sufficient number of positions so as to allow for monitoring of the entire exposure field.
In yet another advantage, because the lens aberration monitor structure of the present invention utilizes sub-resolution features, the actual shape and size of the features are not very critical, and therefore the lens aberration monitor is exceedingly effective in detecting aberrations in actual applications.
Although certain specific embodiments of the present invention have been disclosed, it is noted that the present invention may be embodied in other 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 being indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | A method of detecting aberrations associated with a projection lens utilized in an optical lithography system. The method includes the steps of forming a mask for transferring a lithographic pattern onto a substrate, forming a plurality of non-resolvable features disposed on the mask, where the plurality of non-resolvable features are arranged so as to form a predetermined pattern on the substrate, exposing the mask using an optical exposure tool so as to print the mask on the substrate, and analyzing the position of the predetermined pattern formed on the substrate and the position of the plurality of non-resolvable features disposed on the mask so as to determine if there is an aberration. If the position of the predetermined pattern formed on the substrate differs from an expected position, which is determined from the position of the plurality of non-resolvable features, this shift from the expected position indicates the presence of an aberration. | 6 |
BACKGROUND OF THE INVENTION
Rock drilling by percussion and rotary drilling techniques produces cuttings in the hole formation process which comprise fine dust particles as well as larger rock chips and fragments. It is necessary and desirable to control the drill cuttings, which are normally conveyed from the drill hole by a high velocity air stream, to protect the work environment from unwanted pollution and prevent damage to the drilling equipment and components of the drill cuttings control apparatus.
Examples of prior art drill cuttings control apparatus are disclosed in U.S. Pat. Nos. 3,070,180 to R. F. Norrick and 3,800,890 to L. Gyongyosi et al. The present invention represents improvements in drill cuttings control apparatus over prior art devices in accordance with the advantages and superior features discussed hereinbelow.
SUMMARY OF THE INVENTION
The present invention provides an improved drill cuttings separaion and control apparatus for rock drills and the like wherein pollution of the operating environment of the drill due to air-borne dust and rock chips is minimized and the drill apparatus is protected from damage by relatively large cuttings or rock fragments.
The present invention also provides a drill cuttings control apparatus which provides for improved separation of the air-borne dust from larger particles or fragments as the drill cuttings emanate from the drill hole whereby the heavier drill cuttings are confined by the cuttings control apparatus and are prevented from clogging and damaging the apparatus or from falling back into the drill hole.
The present invention further provides a drill cuttings control apparatus in which air-borne dust is withdrawn from an enclosure over the drill hole in an improved manner providing for additional separation of heavier dust particles from the fluid stream to reduce dust loadings on the dust filters and the like.
The present invention still further provides for an improved drill cuttings separation and control apparatus which includes a hood adapted to be disposed over a drill hole, said hood including improved structure for collecting and separating the drill cuttings ejected from the drill hole by the cuttings evacuation medium. The hood is further constructed to facilitate movement of the cuttings control apparatus laterally away from the hole with the drill rig in the event that a drill stem is left in the hole.
The advantages and superior features of the drill cuttings separation and control apparatus of the present invention may be further appreciated from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a drill cuttings separation and control apparatus according to the present invention; and,
FIG. 2 is a side elevation taken in section along the line 2--2 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, the drill cuttings separation and control apparatus of the present invention is generally designated by the numeral 10. The apparatus 10 is adapted to be used with portable drilling rigs of the percussion or rotary type wherein the drill hole is formed by localized crushing of the rock by impact and forcible penetration of the rock structure. The rock cuttings, namely small chips, fragments, and finer particles called dust are normally evacuated from the hole by a continuous stream of pressure air which is conducted down to the bottom of the hole within the hollow drill stem and is ejected through nozzles or passages in the drill bit. In the drawing FIGS. 1 and 2 the apparatus 10 comprises a hood 12 formed as an inverted rectangular metal box having a deck 14 and depending side walls 16, 18, and 20. A portion of the hood 12 comprising a fourth side wall 22 and a portion of the deck 24 may be separated from the remainder of the hood and is retained in assembly therewith by suitable brackets 23 and fasteners 25. The hood 12 is adapted to be removably fastened to a flange 26 fixed to the lower end of a drill mast or tower 28. The hood 12 is adapted to have a suitable opening 30 in the deck 14 to permit the mast foot 32 to project through the deck into engagement with the ground surface 34 as shown in FIG. 2. The hood 14 is further characterized by sidewall portions formed by a depending flexible skirt 36 which is removably fastened to the sidewalls 16, 18, and 20 and is intended to engage the ground surface to form an enclosure around a drill hole 38. A skirt portion 40 also depends from the sidewall 22 into engagement with the ground surface 34. The skirt portion 40 is mounted on a suitable bracket 42 which is attached to the sidewall 22 by hinges 44. The skirt portion 40 may, accordingly, be swung upward to gain access to the enclosed space 46 formed by the hood 12 for removal of drill cuttings 48 which accumulate on the ground surface 34 around the drill hole. The skirt portions 36 and 40 are preferably made of a durable flexible rubberlike material.
The deck 14 includes a circular opening 50 in which is disposed a flexible seal 52 made of rubber or the like. The seal 52 is adapted to surround and engage a drill stem 54, FIG. 2, to substantially prevent air and dust from exiting or entering the enclosed space within the hood 12 through the deck opening 50. The seal 52 is retained on the deck 14 by an annular collar 56. The seal 52 includes a circular segment 58 which is fastened to the deck portion 24. Further radial slits 60 are formed in the seal 52 to permit entry and withdrawal of a drill bit 62 attached to the distal end of the drill stem 54.
The apparatus 10 is further characterized by a substantially conically shaped cuttings deflector 64 which depends from the deck 14 and has its central axis substantially coaxial with the longitudinal central axis of the drill stem 54. The deflector 64 is formed with a planar surface portion 66 to provide clearance for the mast foot 32. The deflector 64 includes a base 68 which is suitably fastened to the deck by fasteners 70. The conical wall portion of the deflector 64 could be fixed directly to the underside of the deck 14, the last mentioned structure thereby also serving as the base. The deflector 64 includes a conical segment 65 formed between the parting lines 72 and 74 of the removable hood portion 24. The deflector 64 is further characterized by a detachable flexible seal 76 which has an opening coaxially aligned with the axis of the drill stem 54. The seal 76 may be made of a rubberlike material and the opening therein is proportioned to assure that the seal prevents drill cuttings from entering the space 78 defined by the interior of the deflector 64. The seal 76 may be provided with radially extending slits, as are provided for the seal 52, to facilitate entry and withdrawal of the drill bit through the seal. The angle A that the conical surface of the deflector forms with the drill stem axis, which is also the axis of revolution of the cone, is desirably formed to be in the range of 45 to 50 degrees to provide for optimum separation of larger drill cuttings from the finer particles that are ejected from the drill hole.
The deflector 64 still further includes an annular baffle 80 fixed to the exterior of the conical surface of the deflector and spaced from and substantially parallel to the deck 14. The baffle 80 extends around the conical surface of the deflector 64, and includes a portion which may be moved with the deflector segment attached to the hood segment 24. The baffle 80 does not extend along the planar surface 66 in the embodiment shown in the drawings so as to provide clearance for the mast foot 32. The mast foot 32 itself serves as a baffle to some extent. The deflector 64 is provided with a series of apertures 81 disposed spaced apart around the deflector between the baffle 80 and the base 68 which apertures serve to permit the flow of air and whatever drill cuttings are borne therewith from the enclosed space 46 into the space 78. The apparatus 10 is further characterized by a conduit 82 which projects upward from the deck 14 and is disposed around an opening 84 through the deck into the space 78. The opening 84 is disposed adjacent to the outer periphery of the deflector 64. The conduit 82 is adapted to be connected to a source of suction for evacuating the air in the enclosed spaces 46 and 78 formed within the envelope of the hood. The source of suction may comprise a vacuum pump 86. Suitable filtering means 88 for collecting dust and the like may be interposed between the pump 86 and the opening 84.
In the operation of the apparatus 10 pressure air is substantially continuously pumped down through the hollow drill stem 54 and out through passages 90 in the bit 62. The drill cuttings formed by the bit are conveyed up through the annulus formed between the drill stem 54 and the sidewall of the hole 38 at relatively high velocity and are ejected into the enclosed space 46. A substantial portion of the drill cuttings ejected from the hole 38, in the form of rock chips and fragments, impinge against the deflector 64 and fall to the surface 34, or said cuttings merely fall to the surface under the hood 12 as the air velocity decreases upon entry into the enclosed space 46. The conical deflector 64 including the baffle 80 directs the impinging drill cuttings against the sidewalls of the hood 12 whereby they fall to the ground surface and accumulate until periodically removed through the opening provided by the hinged skirt 40.
The aforementioned source of suction applied to the conduit 82 is normally maintained to be sufficient to reduce the air pressure within the enclosure below the ambient atmospheric pressure surrounding the apparatus 10. Accordingly, there is little tendency for drill cuttings to escape from the apparatus around the seal 52 or the skirts 36 and 40. In fact, air tends to flow into the enclosure formed by the hood 12 from leakage around the seal 52 and the skirts. Moreover, the tortuous change in direction of air flowing around the baffle 80 and through the apertures 81 causes further inertial separation of air-borne drill cuttings. Air sucked through the apertures 81 is believed to be induced to flow in a substantially vortical path until it exits through the conduit 82. In like manner air leaking into the space 78 from the space 46 through the clearance and slits in the seal 76 is also believed to be induced to flow in a vortical manner within the space 78. Such a flow path of the air and remaining air-borne particles of drill cuttings tends to further separate many of the particles whereby they impinge on the interior surface of the deflector 64.
Periodic removal of the drill stem from the hole for bit changing or inspection or when drilling is finished allows the drill cuttings which have collected in the interior of the deflector 64 to be dumped through the seal opening 77. The drill rig would normally be moved off of the hole before dumping the cuttings but in any event the volume of cuttings would not be substantial. If it is desired to move the mast 28 and apparatus 10 away from the hole 38 with a section of drill stem still disposed in the hole, the segment 24 of the hood 12 may be first removed to permit lateral movement of the apparatus. | A drill cuttings and dust control hood formed as an inverted rectangular box having depending flexible skirts on three lateral sides and a swinging door formed on a fourth side of the box for drill cuttings removal. The dust control hood includes a conical drill cuttings deflector disposed around the drill stem and directly above the drill hole. The conical deflector includes a plurality of apertures disposed around its base and above a transverse baffle plate. A source of air suction is connected to a tangential outlet opening through the deck of the hood into the interior of the space formed within the conical deflector. Flexible collars on the hood deck and the apex of the conical deflector form dust seals around the drill stem. | 4 |
TECHNICAL FIELD
[0001] The present invention relates to internal combustion engines; more particularly, to devices for controlling the variable actuation of intake valves in an internal combustion engine; and most particularly, to a variable valve actuation assembly for controllably actuating and deactuating a rocker assembly responsive to a triple-lobed cam in an internal combustion engine between high valve lift and low valve lift modes.
BACKGROUND OF THE INVENTION
[0002] Internal combustion engines are well known. In an overhead valve engine, the valves may be actuated directly by camshafts disposed on the head itself, or the camshaft(s) may be disposed within the engine block and may actuate the valves via a valve train which may include valve lifters, pushrods, and rocker arms.
[0003] It is known that for a portion of the duty cycle of a typical multiple-cylinder engine, especially at times of low torque demand, valves may be opened to only a low lift position to conserve fuel; and that at times of high torque demand, the valves may be opened wider to a higher lift position to admit more fuel. It is known in the art to accomplish this by providing a special rocker assembly having a switching or latching pin which may be actuated and/or deactuated electromechanically. The rocker assembly includes both fixed peripheral low-lift cam followers that cause low lift of the valve when the pin is disengaged, and a pivotable central high lift cam follower that causes high lift of the valve when the latching pin is engaged into the high lift follower.
[0004] Various methods for actuating this type of latching pin are known. For example, see the disclosures of U.S. Pat. Nos. 5,619,958; 5,623,848; and 5,697,333. All of these methods employ individual solenoids, acting through bellcranks or similar structures, as part of an actuation system.
[0005] A significant problem for these devices is how to balance the physical size of the solenoid against the force required to actuate the mechanism. The solenoid desirably has rapid response, small size, sufficient stroke and pull-in force, low power requirement, and low sensitivity to voltage and temperature variations; whereas, large size, high pull-in force, and high power are typically required to energize prior art mechanisms.
[0006] One approach, disclosed in the above-referenced patents, is to reduce the solenoid force required by using the rotational motion of the rocker assembly inherent in its duty cycle to supply a portion of the actuating force. Typically, the motion of the rocker assembly permits the solenoid to “pull in” to a low air gap wherein high actuating forces can be generated. The solenoid essentially locks itself in the engaged position during a valve lift event (lift portion of the duty cycle), and some other compliant element in the device, such as a bellcrank, resiliently deflects as the rocker returns to the base circle portion of the cam at the conclusion of the lift event. Once the rocker reaches the base circle, the energy stored in the compliant element causes the locking pin to become engaged with the high-lift follower, shifting the rocker assembly to high-lift mode. This configuration requires the holding force of the solenoid in the actuated position to be greater than the force exerted against it by the compliant element; otherwise, the motion of the rocker assembly will overcome the solenoid and increase the magnetic air gap within the solenoid to a point at which the solenoid force becomes too small to actuate the pin, and the rocker then does not shift to high-lift mode.
[0007] Another prior art approach, disclosed in U.S. Pat. No. 5,623,897, decouples the force generated by the compliant element from the locking force of the solenoid. One end of the compliant element is “grounded” to the cylinder head, and the solenoid moves the opposite end of the compliant element into a position wherein it may engage the rotational displacement of the rocker assembly. The solenoid simply has to hold the compliant element in that position; it is not required to resist the internal force carried by the compressed compliant element.
[0008] The prior art configurations as disclosed have several shortcomings.
[0009] First, several of the linkages are fixed with respect to the pivot point of the rocker assembly, which typically is the ball-head of a hydraulic lash adjuster (HLA) supporting the assembly. The vertical length of the HLA may vary in the normal course of operating, and thus the pivot point may also vary in the z (vertical) direction. Further, the vertical and horizontal (x,y) locations of the pivot point must vary inherently from engine to engine as a result of stack-up of manufacturing tolerances. The prior art disclosures do not address practical or self-compensating means for accommodating tolerances in the cylinder head and cam cover.
[0010] Second, mechanisms disclosed in the prior art typically employ rotating linkages which may add friction to the force required for actuation and thus increase the force requirements of the solenoid.
[0011] Third, none of the disclosed mechanisms, except that shown in U.S. Pat. No. 5,623,897, fully decouples the solenoid force from the compliant element and, therefore, from the pin actuating force. In the disclosure of U.S. Pat. No. 5,623,897, a rotating rocker assembly with a large rocker ratio and large rotational inertia pivots through a relatively large angle in actuating the engine valve. These characteristics add to the force requirements of the solenoid. Further, the solenoid plunger does not act orthogonally to the rocker assembly, resulting in side-loading and friction in the solenoid bearings.
[0012] Fourth, in some prior art mechanisms, the point in the rotational cycle of the cam at which the solenoid is energized must be very carefully timed to avoid a phenomenon known in the art as “ejection” wherein the mechanism attempts to engage or disengage the locking pin into or out of the high-lift follower. When the pin is only slightly engaged, it is violently ejected, which can damage the pin or the high-lift follower and which causes a very loud and objectionable noise. Accurate timing of the solenoid energizing can be complex, as the response time of the mechanism may be affected by various operating parameters, such as oil temperature and thus viscosity.
[0013] It is a principal object of the present invention to provide an improved variable valve actuation (VVA) assembly wherein a secondary latching mechanism between the solenoid and the primary latching pin in the rocker assembly automatically self-times the engagement of the secondary latching mechanism such that the timing of solenoid energizing and de-energizing is not critical and ejections are prevented.
[0014] It is a further object of the invention to provide an improved VVA requiring a low solenoid actuating force and short stroke.
[0015] It is a still further object of the invention to provide an improved VVA wherein variation in assembly performance from the stack-up of manufacturing and operating tolerances among the components of the assembly is minimized.
SUMMARY OF THE INVENTION
[0016] Briefly described, a variable valve actuation assembly for variably opening of an engine intake valve in either a low-lift or high-lift mode includes a special rocker assembly pivotably disposed in the engine for opening and closing the valve and having a central high-lift cam follower and two peripheral low-lift cam followers, responsive to rotation of a camshaft having low-lift and high-lift lobes engageable with the respective cam followers; a primary latching mechanism including a slidable primary latching pin in the rocker assembly for engaging and disengaging the high-lift follower; a solenoid for causing the primary latching pin to be engaged and disengaged; and a secondary latching mechanism between the solenoid and the primary latching pin to automatically limit engagement and disengagement of the primary latching pin to times in the duty cycle of the camshaft when ejections are not possible.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] These and other features and advantages of the invention will be more fully understood and appreciated from the following description of certain exemplary embodiments of the invention taken together with the accompanying drawings, in which:
[0018] [0018]FIG. 1 is an isometric view from above, taken from the camshaft side (camshaft omitted for clarity) showing two variable valve actuation assemblies in accordance with the invention configured for operation of adjacent intake valves of adjacent engine cylinders;
[0019] [0019]FIG. 2 is an isometric view from above of the VVA assemblies shown in FIG. 1, taken from opposite the camshaft side (camshaft omitted for clarity);
[0020] [0020]FIG. 3 is an isometric view similar to that shown in FIG. 1, showing the VVA assemblies installed in the head of an engine;
[0021] [0021]FIG. 4 is a view similar to that shown in FIG. 1, but including a camshaft with high-lift and low-lift cams for one of the VVA assemblies;
[0022] [0022]FIG. 5 is an isometric view, partially exploded, taken from the VVA side opposite the camshaft side, of secondary latching mechanisms in the VVA assemblies shown in FIGS. 1 - 4 ;
[0023] [0023]FIG. 6 is an isometric view, partially in cross-section, similar to that shown in FIG. 5, showing the relationship of the solenoid mounted on an arbor on the engine and a secondary latching pin in the secondary latching mechanisms shown in FIG. 5;
[0024] [0024]FIGS. 7 through 10 are cross-sectional elevational views through a VVA taken along plane 7 - 10 in FIG. 4, showing successive stages in one operating cycle of a VVA in accordance with the invention; and
[0025] [0025]FIG. 11 is another view of FIG. 1 showing cam follower rollers as an alternate embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Referring to FIGS. 1 and 2, an improved dual variable valve actuation (VVA) assembly 10 in accordance with the invention is shown for variable actuation of two separate valves 12 of internal combustion engine 13 . Assembly 10 includes two separate, substantially identical VVA mechanisms 10 ′ sharing a common arbor 14 mountable onto an engine head 94 (as shown in FIG. 3). As the two VVA assemblies are substantially mirror images of each other, the following discussion is directed to only one VVA but should be understood as being applicable to both except as noted. Each mechanism 10 ′ includes a rocker assembly 16 and a secondary latching assembly 18 . Rocker assembly 16 is pivotably mounted, preferably by a ball-and-socket joint, on a conventional hydraulic lash adjuster (HLA) 20 and is pivotably connected near a distal end 22 to the stem of a valve 12 .
[0027] Referring to FIGS. 1 and 2 and any of FIGS. 7 through 10, rocker assembly 12 is similar to two-stage rocker assemblies known in the art, as described above. A frame 24 has a spherical socket 26 for pivotably mating with the ball head 28 of HLA 20 . Frame 24 provides a rigid but pivotable bridge between HLA 20 and valve 12 , and is formed having a generally rectangular longitudinal aperture 30 for receiving a high-lift cam follower 32 having a surface for following a high-lift cam lobe as described below. Follower 32 is pivotably pinned at one end by pin 34 in slot 36 formed in frame 24 in communication with aperture 30 . Preferably, a first torsion spring (not shown) is disposed on pin 34 in slot 36 to bias follower 32 upwards into continual contact with its respective cam lobe. Frame 24 further is provided with two rigidly-mounted low-lift cam followers 38 , each having a surface for following a low-lift cam lobe as described below.
[0028] At the proximal end 40 of rocker assembly 16 , a primary latching assembly 17 in frame 24 includes a stepped bore 42 slidably receivable of a primary latching pin 44 comprising a latching portion 46 and a trigger portion 48 . Pin 44 is urged away from high-lift follower 32 by a compression spring 50 disposed in bore 42 between frame 24 and trigger portion 48 . When follower 32 is suitably positioned (as shown in FIG. 10), portion 46 may be moved axially of bore 42 to engage portion 46 under latching nose 52 of follower 32 , thereby preventing follower 32 from rotating about pin 34 , and transforming rocker assembly 16 into high-lift mode, as described below.
[0029] Referring to FIGS. 5 through 10, secondary latching assembly 18 includes a backer frame 54 having a central aperture 56 for receiving a blocker plate 58 therein. Backer frame 54 is provided with bores 60 for receiving pivot screw 62 which is threadedly received in a bore in arbor 14 to pivotably attach frame 54 to arbor 14 . A shim 64 on screw 62 spaces frame 54 a predetermined distance from arbor 14 and supports a second torsion spring 66 engaged by a first tang 68 into arbor 14 and by a second tang 70 onto frame 54 for urging frame 54 pivotably toward rocker assembly 16 . As shown in FIGS. 5 and 6, each siderail 72 of frame 54 is further provided with a stepped bore 74 for receiving a stepped secondary latching pin 76 having a flat boss 78 at one end thereof. A compression spring 80 is disposed in bore 74 around pin 76 for urging pin 76 outwards of bore 74 . Only one bore 74 is used for each frame 54 , but preferably the two bores 74 provided in each frame are mirror images of each other so that a single configuration of frame 54 may be used for either of the assemblies 18 shown in these figures.
[0030] Blocker plate 58 is provided with a first bore 82 at an end thereof for receiving screw 62 to pivotably mount plate 58 between bores 60 in frame 54 such that plate 58 can swing through aperture 56 . A third torsion spring 75 is disposed on screw 62 coaxially with plate 58 and is configured conventionally to urge plate 58 rotationally of screw 62 against trigger portion 48 . Plate 58 is further provided with a medial bore 84 for receiving secondary latching pin 76 to rotationally lock plate 58 to frame 54 when so desired.
[0031] Frame 54 is further provided with an actuating extension 77 for engaging with the bearing surface 79 of rocker proximal end 40 . Preferably, the bearing surface 81 of extension 77 is included in a plane including the pivot axis 83 of backer frame 54 and bearing surface 79 is a cylindrical arc centered on the center of arcuate pad 85 which interfaces with the stem of valve 12 . As rocker assembly 16 oscillates about HLA head 28 during actuation thereof, surface 79 rotates and slides along surface 81 at a constant radius, and therefore the position of backer frame 52 is unaffected by such action. Further, these geometric relationships make the VVA mechanism virtually insensitive to normal manufacturing, assembly, and operating variations in the size and position of these components.
[0032] Arbor 14 is provided with a well 87 for receiving a solenoid 86 having an armature plunger 88 extending toward boss 78 on pin 76 in a direction orthogonal to plane 7 - 10 (FIG. 4), which is the actuation plane of assembly 10 ′, and parallel to the axis of rotation of the camshaft. When solenoid 86 is energized, pin 76 is urged toward blocker plate 58 in attempt to enter into bore 84 to lock plate 58 to frame 54 . Such entry is permitted under conditions as described below, wherein bore 74 becomes axially aligned with bore 84 . Where entry is not permitted immediately upon energizing of the solenoid, the energized solenoid acts as a cocked electromechanical spring and will insert pin 76 into bore 84 at the earliest opportunity during the camshaft duty cycle, as described below.
[0033] Referring to FIGS. 3 and 4, a camshaft 90 is carried in bearing mounts 92 formed in engine head 94 which positions cam lobes for actuation of valves 12 via rocker assembly 16 . In FIG. 4, the camshaft and cam lobes are shown for only one valve, but it should be understood that identical lobes are provided for each valve having an associated VVA mechanism. Camshaft 90 is provided with a central high-lift lobe 96 , which is followed by central high-lift follower 32 , and a pair of identical peripheral low-lift lobes 98 flanking lobe 96 , which are followed by peripheral low-lift followers 38 .
[0034] The conversion of a VVA assembly 10 ′ from low-lift mode (default mode) to high-lift mode is shown sequentially in FIGS. 7 through 10. Beginning with FIG. 7, in default low-lift mode, primary latching pin 44 is disengaged from high-lift follower 32 . Valve 12 is closed. Low-lift cam lobe 98 is engaged on its base circle portion 100 with low-lift follower 38 , and high-lift cam lobe 96 is engaged on its base circle portion 102 with high-lift follower 32 . Solenoid 86 is de-energized and therefore secondary latching pin 76 is disengaged from blocker plate 58 which is pivoted out of alignment by contact with trigger portion 48 at contact point 112 . Thus compression spring 50 which urges primary latching pin 44 out of engagement must be stronger than, and overcome, third torsion spring 75 . To begin the change from low-lift mode to high lift mode, solenoid 86 may be energized at any time during the camshaft duty cycle. Plunger 88 of the solenoid forcibly engages boss 78 (not visible in FIGS. 7 - 10 ) but secondary latching pin 76 cannot yet enter bore 84 because of axial misalignment. Secondary latching pin 76 is thus cocked by the energized solenoid to enter bore 84 in the blocker plate to lock the blocker plate to the backer frame 54 as soon as bore 84 becomes coaxially aligned with the pin.
[0035] Referring to FIG. 8, a low-lift event is shown in progress. The camshaft has rotated the cam lobes counterclockwise such that eccentric portion 104 of low-lift lobe 98 is engaged with low-lift follower 38 , thereby rotating rocker assembly 16 clockwise about HLA head 28 and opening valve 12 with low lift. Eccentric portion 106 of high-lift lobe 96 is similarly engaged with high-lift follower 32 , but because follower 32 is disengaged from primary latching pin 44 the follower simply pivots on pin 34 without lift effect on valve 12 . Note that bearing surface 108 on trigger 48 is preferably cylindrically arcuate and bearing surface 110 on blocker plate 58 is preferably flat. Comparing the contact point 112 between these two surfaces in FIG. 7 and FIG. 8, it is seen that the surface 108 moves along surface 110 in a combination sliding and rolling motion in response to the clockwise rotation of rocker assembly 16 . The angle of surface 110 with respect to pivot point 83 is such that the relationship of blocker plate 58 to backer frame 54 does not vary with tolerance variations in the cylinder head, an importance advance in the art conferred by an assembly in accordance with the invention. Further, because the change in contact point between the bearing surfaces is eccentric with respect to the pivot point of the rocker assembly, blocker plate 58 is permitted to pivot counterclockwise slightly about pivot axis 83 , bring bore 84 into alignment with pin 76 , which then enters bore 84 at the urging of the previously energized solenoid. Because the pin is small and of low mass, and because bore 84 is aligned with pin 76 by the natural motion of rocker assembly 16 imparted by the engine, solenoid 86 may be very small and relatively weak, thus overcoming the disadvantages of prior art VVA mechanisms as described above. This is an important advantage of a VVA assembly in accordance with the invention.
[0036] Referring to FIG. 9, as the low-lift event progresses, the cam lobes have rotated further counterclockwise such that the followers are in contact with the lobes at the point of merger between the eccentric portions 104 , 106 and the base circle portions 100 , 102 of the lobes 98 , 96 . Valve 12 has been closed by the action of a conventional valve spring (not shown), causing rocker assembly 16 to rotate counterclockwise back to its rest position, as shown previously in FIG. 7. However, blocker plate 58 is not free to also return to its former position because it is now locked to backer frame 54 , as was seen in FIG. 8. Further, latching portion 46 of primary latching pin 44 is still in slight interference with latching nose 52 . Therefore, the locked unit of backer frame and blocker plate is pivoted clockwise about axis 83 against second torsion spring 66 , cocking the primary and secondary latching mechanisms for engagement of primary latching pin 44 with latching nose 52 at the earliest opportunity.
[0037] Referring to FIG. 10, the low-lift event is completed and rocker assembly 16 is locked in high-lift mode by primary locking pin 44 . The cam lobes have rotated slightly farther than as shown in FIG. 9, onto their respective base circle portions, and high-lift follower 32 has pivoted farther clockwise about pivot pin 34 , bringing latching nose 52 into latching alignment with latching portion 46 . Second torsion spring 66 is stronger than compression spring 50 and immediately urges primary latching pin 44 into engagement with latching nose 52 , compressing spring 50 and completing the conversion of the rocker assembly from low-lift mode to high-lift mode. During the next revolution of the camshaft, the high-lift eccentric of lobe 96 will cause rocker assembly 16 to rotate through a greater angle than in the previous duty cycle, thereby opening valve 12 wider (higher lift) than in its previous opening.
[0038] Both primary latching pin 44 and secondary latching pin 76 will remain engaged as long as solenoid 86 is energized; the assembly will thus remain in high-lift mode. To shift back to low-lift (default) mode, the solenoid may be de-energized at any point. It will be seen that there is no shear force on secondary pin 76 while either a low-lift or high-lift event is in progress (eccentric lobe portions are engaged). Thus pin 76 is free to engage or disengage with bore 84 at any such time. De-energizing the solenoid during the high-lift event permits compression spring 80 to eject pin 76 from bore 84 ; however, primary latching pin 44 remains engaged with latching nose 52 because of shear force therebetween. When the lobes return to their base circles and such shear force is removed, compressed spring 50 immediately urges primary latching pin out of engagement with nose 52 . Blocker plate 85 is free to pivot away, and the assembly is returned to the default low-lift mode shown in FIG. 7.
[0039] It is an important advantage of a VVA assembly in accordance with the invention that the engagement of the primary latching pin with the high-lift follower necessarily occurs at the beginning of the base circle lobe engagement, at a point of no shear force between the pin and the follower. Thus, ejections of the primary latching pin, as are well known in the prior art, are rendered impossible. Further, because the secondary latching pin engages the blocker arm only when they are axially aligned, which occurs only during the lift portion of a low-lift duty cycle, the solenoid need be only strong enough to displace the secondary pin axially a short distance.
[0040] While the invention has been described by reference to various specific embodiments, it should be understood that numerous changes may be made within the spirit and scope of the inventive concepts described. For example, high-lift and low-lift cam followers 32 , 38 are shown as sliders herein but some or all of the followers may instead be provided as rollers rotatably mounted to frame 24 within the scope of the invention. For example, in FIG. 11, roller 38 ′ is shown instead of slider 38 . Accordingly, it is intended that the invention not be limited to the described embodiments, but will have full scope defined by the language of the following claims. | A variable valve actuation assembly for actuation of an engine intake valve between low-lift and high-lift modes. The VVA assembly includes a special rocker assembly having a pivotable central high-lift cam follower and two peripheral low-lift cam followers; a camshaft having low-lift and high-lift lobes engageable with the respective cam followers; a primary latching assembly including a slidable primary latching pin in the rocker assembly for engaging and disengaging the high-lift follower; a solenoid for causing the primary latching pin to be engaged and disengaged; and a secondary latching mechanism between the solenoid and the primary latching pin to automatically limit engagement and disengagement of the primary latching pin to times in the duty cycle of the camshaft (during lift events) when ejections of the primary latching pin are not possible. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
I hereby claim benefit under Title 35, United States Code, Section 119(e) of U.S. provisional patent application Ser. No. 60/346,730 filed Jan. 8, 2002. The 60/346,730 application is currently pending. The 60/346,730 application is hereby incorporated by reference into this application.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to building-material displays and more specifically to a rotating display system for assisting customers in visualizing various combinations of structures used in kitchens and bathrooms such as cabinets, countertops, backsplashes, flooring, and shower walls.
2. Description of the Related Art
Displays in the building industry have been in use for years. The most commonly utilized display is comprised of a rack displaying a plurality of countertop surface material that is not usually displayed with the other coordinating surfaces together. Another type of display is a board structure that supports a plurality of tile or countertop materials to illustrate the available options. The user must bring the product samples together with other surface options into a single location for visualization. Usually not all samples are available in one store.
The main problem with conventional displays is that they do not allow the user to combine and visually see various combinations of the coordinating surfaces together. A further problem with conventional displays is that numerous display units are required which consumes a significant amount of showroom space. Another problem with conventional displays is that it is time consuming for users to bring product samples to other stores for comparison purposes. Another problem with conventional displays is that they do not provide an accurate representation of the overall appearance of the combination in a building setting.
While these devices may be suitable for the particular purpose to which they address, they are not as suitable for assisting customers in visualizing various combinations of structures used in kitchens and bathrooms such as cabinets, countertops, backsplashes, flooring, and shower walls. Conventional building material displays do not provide an efficient display system that can be easily utilized for effectively displaying various combinations of coordinating building materials.
In these respects, the rotating display system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of assisting customers in visualizing various combinations of structures used in kitchens and bathrooms such as cabinets, countertops, backsplashes, flooring, and shower walls.
BRIEF SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of displays now present in the prior art, the present invention provides a new rotating display system construction wherein the same can be utilized for helping customers visualize various coordinating surfaces including but not limited to cabinet, countertop and backsplash options thereby facilitating purchases.
The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new rotating display system that has many of the advantages of the displays mentioned heretofore and many novel features that result in a new rotating display system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art displays, either alone or in any combination thereof.
To attain this, the present invention generally comprises a frame with each part being rotatable and able to be used to display (but not limited to) a cabinet display rotatably supported above a surface, a countertop display rotatably positioned above the cabinet display, and a backwash display rotatably positioned above said countertop display. The cabinet display has a plurality of sample cabinet surfaces, the countertop display has a plurality of sample countertop surfaces, and the backsplash display has a plurality of sample backsplash surfaces. The user rotates the cabinet display, the countertop display and the backsplash display to visually illustrate various options and combinations, or, in the example of a shower display, can be constructed to fit shower wall sample panels with two or more layers and a flooring layer.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.
A primary object of the present invention is to provide a rotating display system that will overcome the shortcomings of the prior art devices.
A second object is to provide a rotating display system for assisting customers in visualizing various combinations of structures used in kitchens and bathrooms such as cabinets, countertops, backsplashes, flooring, and shower walls.
Another object is to provide a rotating display system that is compact in size and requires a minimal amount of showroom space.
An additional object is to provide a rotating display system that provides one convenient location for customers to view various options and combinations of coordinating surfaces.
A further object is to provide a rotating display system that is easily manipulated to achieve various combinations.
Another object is to provide a rotating display system that provides an actual visual and physical representation of various combinations of coordinating surfaces.
A further object is to provide a rotating display system that assists salespeople in designing a space and which reduces the amount of time spent with each customer.
Other objects and advantages of the present invention will become obvious to the reader and it is intended that these objects and advantages are within the scope of the present invention.
To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated or surfaces used for display and described within the scope of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
FIG. 1 is an exploded upper perspective view of a first embodiment of the present invention.
FIG. 2 is an upper perspective view of the present invention.
FIG. 3 is an upper perspective of the present invention illustrating some rotational movements of the main components.
FIG. 4 is a top view of the present invention.
FIG. 5 is a front view of the present invention.
FIG. 6 is an upper perspective view of a second embodiment of the present invention.
FIG. 7 is an upper perspective view of a third embodiment of the present invention.
FIG. 8 is an upper perspective view of a fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A. Overview
Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views. FIGS. 1 through 5 illustrate a rotating display system 10 , which comprises a cabinet structure 20 to display (for example) a sample cabinet display, a frame to display, for example, a countertop display 40 rotatably positioned above the cabinet display rack 20 , and frame or structure to display, for example, a backsplash display rotatably positioned above said countertop display 40 . The cabinet display 20 has a plurality of sample cabinet surfaces, the countertop display 40 has a plurality of sample countertop surfaces, and the backsplash display 50 has a plurality of sample backsplash surfaces. The user rotates the cabinet display 20 , the countertop display 40 and the backsplash display 50 to visually illustrate various options and combinations. It can be appreciate that other coordinating surface materials can be used for display on this rotating display system.
B. Support Stand
FIG. 1 illustrates an exemplary support stand 30 for rotatably supporting the cabinet display 20 , the countertop display 40 and the backsplash display 50 . It can be appreciated that various other support structures may be utilized to rotatably support the cabinet display 20 , the countertop display 40 and the backsplash display 50 with respect to one another and the support stand 30 illustrated is merely for illustration purposes. For example, the cabinet display 20 , the countertop display 40 and the backsplash display 50 could be directly rotatably supported upon one another utilizing bearings, wheels or similar rotating mechanisms.
The support stand 30 has a support base 32 and a support pole 34 extending from the support base 32 . The support base 32 may have various broad structures for adequately supporting the cabinet display 20 , the countertop display 40 and the backsplash display 50 . For example, the support base 32 may have a broad structure, as shown in FIG. 1 , or the support base 32 may have a plurality of horizontal leg units. The support pole 34 is preferably comprised of an elongate rigid structure.
The support pole 34 extends upwardly from the support base 32 and rotatably receives the cabinet display 20 , the countertop display 40 and the backsplash display 50 . The cabinet display 20 , the countertop display 40 and the backsplash display 50 are preferably removably attached to the support pole 34 utilizing conventional fastening devices which allow for rotatably supporting the respective cabinet display 20 , the countertop display 40 and the backsplash display 50 with respect to one another. For example, locking collars may be attached to the support stand 30 with bearings attached to the cabinet display 20 , the countertop display 40 and the backsplash display 50 which rotatably rest upon the locking collars. Various other rotating structures may be utilized to rotatably support the cabinet display 20 , the countertop display 40 and the backsplash display 50 with respect to one another.
C. Cabinet Display
The cabinet display 20 is the base of the present invention which is rotatably supported upon or above a floor surface. For example, the cabinet display 20 may have an upper surface 22 with a cabinet aperture 26 within for receiving the support pole 34 as shown in FIG. 1 of the drawings.
The cabinet display 20 has a plurality of cabinet sections 24 a–d preferably forming a square, rectangular, oval or polygonal structure. The number of cabinet sections 24 a–d may vary such as but not limited to 2, 3, 4, 5, 6, 7 and 8 or more sections. FIG. 8 illustrates an alternative embodiment where the sections face outwardly instead of towards one another. The applicant has found that 4 cabinet sections 24 a–d provides minimum the desired visual effect as shown in FIG. 2 of the drawings. The cabinet sections 24 a–d preferably have a height and width similar to a conventional lower cabinet and may be constructed in a horizontal or parallel manner depending on the surface material being displayed.
Each of the cabinet sections 24 a–d for example purposes represents a various cabinet options for the user. The cabinet sections 24 a–d may have various wood and material types, styles, structures, colors and textures. The drawings merely illustrate some exemplary cabinet designs for illustration purpose and should not limit the present invention.
D. Countertop Display
The countertop display 40 for example purposes is a relative flat structure for this example representing a countertop surface. The countertop display 40 is rotatably supported upon or above the upper surface 22 of the cabinet display 20 . The countertop display 40 has a countertop aperture 42 that rotatably receives the support pole 34 as shown in FIG. 1 of the drawings.
The countertop display 40 has a plurality of cabinet sections 44 a–d preferably forming a triangular, square, rectangular, oval or polygonal shape. FIG. 8 illustrates an alternative embodiment where the sections face outwardly instead of towards one another. The number of countertop sections 44 a–d may vary such as but not limited to 2, 3, 4, 5, 6, 7 and 8 sections. It is desirable to utilize the same number of countertop sections 44 a–d as the number of cabinet sections 24 a–d utilized, though various other countertop sections 44 a–d may be utilized. The countertop sections 44 a–d preferably extend from each corner of the cabinet sections 24 a–d toward a central location.
The countertop display 40 has a plurality of countertop sections 44 a–d that represent various countertop options for the user. The countertop sections 44 a–d may have various material types, styles, colors, thicknesses, and textures. The drawings merely illustrate some exemplary countertop designs for illustration purposes and should not limit the present invention.
E. Backsplash Display
The backsplash display 50 , for purposes of example only, is comprised of a plurality of partitions 52 a–d for illustrating various backsplash designs. FIG. 8 illustrates an alternative embodiment where the sections face outwardly instead of towards one another. The number of partitions 52 a–d utilized depends upon the number of countertop sections 44 a–d utilized. The partitions 52 a–d are formed to align along the borders of each of the countertop sections 44 a–d as best illustrated in FIG. 4 of the drawings. In the preferred embodiment of the present invention, four partitions 52 a–d are utilized forming an X-shaped structure as best illustrated in FIGS. 2 and 4 of the drawings.
The backsplash display 50 is preferably rotatably positioned upon or above the countertop display 40 . For example, the backsplash display 50 may be rotatably attached to the upper portion of the support pole 34 .
The backsplash display 50 has a plurality of backsplash sections 54 a–d which represent various backsplash options for the user. The backsplash sections 54 a–d may have various material types, styles, colors, designs, and textures. The drawings merely illustrate some exemplary backsplash designs for illustration purposes and should not limit the present invention, nor should this display be limited to backsplashes.
F. Alternative Embodiment
FIG. 6 illustrates a second embodiment of the present invention. The second embodiment has a flooring display 60 which has a plurality sections that may have various material types, styles, colors, designs, and textures. The drawings merely illustrate some exemplary flooring designs for illustration purposes and should not limit the present invention, nor should this display be limited to flooring materials. The flooring display 60 may be added separately by the user or it may be integral with the present invention.
The second embodiment also has a lower wall display 62 which has a plurality sections that may have various material types, styles, colors, designs, and textures. The lower wall display 62 is rotatably positioned upon or above the flooring display 60 as shown in FIG. 6 of the drawings. The drawings merely illustrate some exemplary lower wall designs for illustration purposes and should not limit the present invention, nor should this display be limited to wall materials.
The second embodiment also has an upper wall display 64 which has a plurality sections that may have various material types, styles, colors, designs, and textures. The upper wall display 64 is rotatably positioned upon the lower wall display 62 as shown in FIG. 6 of the drawings. The drawings merely illustrate some exemplary lower wall designs for illustration purposes and should not limit the present invention, nor should this display be limited to wall materials.
FIG. 7 of the drawings illustrates a third embodiment which simply utilizes the exterior surfaces of polygonal structures to create the desired combinations. The present invention should not be limited to the structures as shown in the drawings.
G. Operation
In use, the user rotates the cabinet display 20 , the countertop display 40 and the backsplash display 50 until a desired combination is achieved. For example, the user may first select a desired cabinet appearance by selecting one of the cabinet sections 24 a–d. The selected cabinet section is retained towards the front as shown in FIG. 5 and the user then rotates the countertop display 40 until a desired countertop-cabinet combination is achieved. The user then rotates the backsplash display 50 until the desired countertop-cabinet-backsplash combination is achieved as shown in FIGS. 2 and 4 of the drawings. When the desired combination is shown, the partitions 52 a–d hide the non-selected countertop sections 44 a–d thereby providing the user with an overall visualization of the selected countertop-cabinet-backsplash combination.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed to be within the expertise of those skilled in the art, and all equivalent structural variations and relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A rotating display system for assisting customers in visualizing various combinations of structures used in kitchens and bathroom, such as cabinets, countertops, backsplashes, flooring, and shower walls. The rotating display system includes a cabinet display rotatably supported above a surface, a countertop display rotatably positioned above the cabinet display, and a backwash display rotatably positioned above said countertop display. The cabinet display has a plurality of sample cabinet surfaces, the countertop display has a plurality of sample countertop surfaces, and the backsplash display has a plurality of sample backsplash surfaces. The user rotates the cabinet display, the countertop display and the backsplash display to visually illustrate various options and combinations. | 6 |
This is a continuation of application Ser. No. 08/066,473 filed on May 24, 1993 and abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the manufacture of cellulose fiber by a method comprising the spinning of continuous cellulose filaments from a solution of cellulose in an organic solvent, particularly an amine oxide solvent. Cellulose manufactured in this manner is known as lyocell and will hereafter be referred to as solvent-spun cellulose or lyocell. The invention particularly aims to provide a detection means to enable the presence of so-called "trash" on the formed continuous filaments to be detected at an appropriate stage in the manufacturing process.
2. Description of the Related Art
The manufacture of lyocell cellulose filaments is described, for example, in U.S. Pat. No. 4,416,698 the contents of which are incorporated herein by way of reference. This Patent discloses a method of producing cellulose filaments by dissolving the cellulose in a suitable solvent such as a tertiary amine N-oxide.
A hot solution of the cellulose is extruded or spun through a suitable die assembly including a jet to produce filamentary material which is passed into water to leach out the amine oxide solvent from the extruded filaments.
The production of artificially formed filaments of material by extruding or spinning a solution or liquid through a spinnerette to form the filaments is, of course, well known. Initially, relatively small numbers of individual filaments were prepared, which filaments were individually wound up for use as continuous filament material. This meant that the number of continuous filaments which needed to be produced was essentially dictated by the number of filaments which could be individually wound either before or after drying.
However, if fiber is produced as a tow or if fiber is produced as a staple fiber then different criteria apply to the number of filaments which can be produced at any one time. A tow essentially comprises a bundle of essentially parallel filaments which are not handled individually. Staple fiber essentially comprises a mass of short lengths of fiber. Staple fiber can be produced by the cutting of dry tow or it can be produced by forming a tow, cutting it whilst still wet, and drying the cut mass of staple fiber.
Because there is no need to handle individual filaments in the case of a tow product or a staple product, large numbers of filaments can be produced simultaneously.
One problem encountered in the commercial production of solvent-spun cellulose filamentary tows as described above is that "trash" can become attached to the filaments and so degrade their quality. "Trash" in this process is usually in the form of globules of cellulosic polymer formed from the "dope" or hot solution of cellulose. These globules have not been spun into filamentary form and they attach themselves to the filaments of the formed tow. "Trash" can also be formed by pieces of broken filamentary fiber. It can occur from time to time for a variety of reasons. For example, breakage may occur due to the tensions applied to the formed filaments at various points in the manufacturing process. Polymer globules may be caused, for example, by partial blockage of one or more of the spinning holes. Broken filaments, being undrawn, are much thicker than the drawn filaments.
Accordingly it is an object of the present invention to provide detection means in the manufacturing process to alert to the formation of "trash" on the tow of cellulose filaments.
SUMMARY OF THE INVENTION
The invention provides an apparatus for the detection of faults on a tow of continuous filaments of solvent-spun cellulose, which comprises means to mix cellulose and a solvent to form a hot cellulose solution, means to form a tow of continuous filaments from the hot solution, a bath through which the tow can be passed to leach the solvent from the filaments and detection means, the detection means comprising means to project a beam across the tow, preferably while still wet, and receiving means on the opposite side of the tow to the means to project the beam, the receiving means being calibrated to initiate a signal if obscurement of the beam by the tow varies beyond a predetermined amount.
The solvent will preferably be a tertiary amine N-oxide and the bath a water bath to leach out the solvent.
The detection means may be installed at any desired position in the manufacturing process and, indeed, detection means may be installed at more than one position in the process, if so desired.
Particularly suitable positions to locate the detection means are:
i) between the spinning, i.e. extrusion, stage where the filamentary tow is formed and the washing stage to leach out the solvent,
ii) after the washing stage, while still wet and
iii) if the washed filamentary tow is to have crimp applied to it, immediately before the crimping stage.
In the latter instance, the tow of fibers, which is normally dried in an oven after the washing stage, will pass through the detection means between the drying stage and the crimping stage.
The detection means preferably comprises a source of collimated infra red light or a laser beam, which is projected across the path of travel of the tow and is received by a photo-receiver, for example a silicon photo diode. The detection means is calibrated so that the desired amount of beam blockage by the desired thickness of the tow causes no alarm signal. However, any change, e.g. increased blockage of the beam caused by "trash" or undesired change in thickness of the tow, causes a change in the electrical output of the photo-receiver. Any change beyond a predetermined amount triggers an appropriate signal. For example, it may trigger an audible alarm.
The detection means is preferably coupled to a microprocessor which has been programmed to analyse the data fed to it by the receiver. The microprocessor can, therefore, initiate any desired alarm and can also be used to maintain overall records for quality control analysis purposes.
It will be appreciated that in a largely automated manufacturing process an audible alarm signal will be desirable in view of the unpredictable and intermittent nature of the occurrence of "trash" on the tow.
BRIEF DESCRIPTION OF THE DRAWINGS
Specific embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:
FIG. 1 is a diagrammatic representation of the various stages in the manufacture of a continuous tow of solvent-spun cellulose fibers, i.e. lyocell;
FIG. 2 is a diagrammatic side view showing a detection means positioned in the manufacturing process of FIG. 1;
FIG. 3 is a plan view of the position shown in Figure 2;
FIG. 4 is a side view showing the tow passing through the detection means in a first embodiment;
FIG. 5 is a similar side view to FIG. 4 but showing the tow passing through the beam of a detection means in a second embodiment; and
FIG. 6 is a diagrammatic representation showing the detection means at a different position in the manufacturing process.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, is shown a mixer 10 with inlets 11 and 12 to receive shredded cellulose and an amine oxide solvent respectively. The hot solution is pumped via metering pump 13 to a spinnerette 14 where the solution is spun into a continuous tow 15 of fibers.
As the hot tow leaves the spinnerette 14 it is passed through a spin bath 16 in which a mixture of water and the amine oxide is recirculated. At start-up there will be no amine oxide in the spin bath but its proportion to water may rise to about 40% by weight, e.g. 25% by weight. From spin bath 16 the tow is passed via roll 17 through a water bath 18. The tow passing through the water bath may be, for example, up to 12 to 14 inches wide. In the water bath, the amine oxide is dissolved out of the fibers and the tow 19 emerging from the water bath is of solvent-spun cellulose, i.e. lyocell.
From water bath 18 the tow 19 is passed through a nip between rolls 20 and 21 and, while still wet from both 18, to a detection means 30, which is described in greater detail below with reference to Figures 2 and 3. The tow is then passed through a finishing stage 30A where the filaments are lubricated using spin finishes well known in the art. The tow is then passed through a drying oven 22 maintained at a temperature of about 100° to 180° C. e.g. 165° C.
The drying oven is preferably of the perforated drum type, well-known in the art, but may, alternatively, be of the can or calender drier type.
There may be, as shown, a single tow emerging from the spinnerette and this may contain, for example, up to 400,000 filaments and may weigh, for example 65 ktex, i.e. 65 g/meter, after the drying stage. Alternatively, the spinnerette may produce more than one, for example, four streams of tow and these may contain over 1 million filaments each and weigh, for example, about 181 ktex each after drying.
A single tow passing through the water bath may be, as indicated above, up to 12 to 14 inches wide. However, where four tows, for example, are produced from the spinnerette, these may be combined into two tows, each pair of tows going through a separate water bath which is at least 48 inches wide and each pair of tows 24 inches wide.
The dry tow from drier 22 is then passed into a nip defined by rolls 23 and 24 from which it is fed into stuffer box 25. The crimped tow 26 emerging from the stuffer box is passed via roll 27 to a cutter 28 where it is cut to staple fiber lengths. The crimped staple fiber lengths are collected in a box 29.
In FIG. 2 and 3 the tow 19 is shown passing from rolls 20 and 21 through the detection means 30. The detection means comprises a counter base 31 above which are set rolls 32 and 33 over which the tow passes. Between rolls 31 and 32 the tow passes in front of an infra-red light source 34 which projects an infra-red beam across the path of travel of the tow. On the other side of the tow from light source 34 is a silicon photo-diode receiver 35 which detects the infra-red beam passing across the tow. As indicated above, at this point, the tow may be from 12 to 14 inches wide so that light source 34 and receiver 35 are spaced apart by a little more than that amount.
As shown in FIG. 4, the beam 36 is set so that tow 19 passes centrally through it. If desired the bottom half of the beam, i.e. below tow 19 may be blocked off from the receiver by, e.g. a brass shield 37. This enables the system to run without alarm or counting of occasional loose edges appearing beneath the tow.
Alternatively, the beam 36 may be set a little higher relative to the tow 19 so that the tow passes through its lower half--see FIG. 5. The tow may be, for example about 2 mm above the bottom of a beam of diameter about 10 mm. In this set up sensitivity of the detection means is increased towards larger obstructions. In FIG. 4, an obstruction of height 2x is seen to produce less than double the obscurement of the beam caused by an obstruction of height x. In FIG. 5, an obstruction of height 2x gives obscurement of the beam more than double that caused by an obstruction of height x. Thus it can be appreciated that the position of the beam relative to the tow can be adjusted according to the type and size of trash or other obstruction preferably wished to be detected.
The system is calibrated so that a predetermined level of obscurement of the beam will increment a counter in counter base 31 and sound an alarm 50. Counter base 31 may contain or be connected to a microprocessor which may control the alarm and analyse the counter data.
The detection means may also be calibrated to allow for gradual changes in tow thickness whereby it slowly automatically compensates for changes in the amounts of light received by the receiver. Thus, if for example, 50% of the beam becomes obscured for any length of time, the remaining 50% becomes the "normal" level and the sensitivity is, therefore, doubled. In other words, the detection means counts sudden changes in the level of light received, while at the same time slowly adjusting the notional normal or "zero" obscurement level.
It will be appreciated that various embodiments may be changed from those described above without departing from the scope and spirit of the invention., In particular, the detection means may as previously suggested, be positioned at a different stage in the process. Thus it may be found useful to position a detection means immediately after the filament spinning stage and before the washing stage to leach out the amine oxide solvent. The tow may be positioned to travel just outside the path of the beam so that the beam is only interfered with by, e.g. trash, extending from the tow.
The detection means may, of course, be incorporated in a process in which the tow is not crimped or in which the tow is crimped but is not passed to a cutter.
An alternative embodiment is, therefore, described with reference to FIG. 6. In this embodiment a detection means 40 of the same type as described above is positioned between the spinnerette 14 in which the tow of filaments has been formed and the water bath (not shown) in which the solvent is leached out.
In this embodiment the detection means 40 is so positioned that as tow 19 passes over roll 41, the lowermost portion of the beam traverses the travel path of the tow a small distance above the top of the tow. This distance may be adjusted according to the minimum upstanding size of trash or other unwanted material that it is desired to detect. For example, the gap between the beam and the tow may be up to 3/8 inch.
The receiving diode in this embodiment may be connected to an alarm, counting means and microprocessor as previously described. | In a system for the production of solvent-spun cellulose tow, trash and other undesirable material is detected by a device which projects a light beam across the tow and a receiver for the beam which initiates a signal if the beam is obscured beyond a predetermined amount. | 3 |
TECHNICAL FIELD
[0001] The present invention relates to the technical field of oil refining.
TECHNICAL BACKGROUND
1. The Compression Ratio and Thermal Efficiency of Engines
[0002] The compression ratio refers to the ratio of the largest volume of the gas and the smallest volume of the gas that can be obtained in the cylinder during the movement of the piston. When the piston is at the bottom of its stroke in the cylinder, the gas therein has the largest volume; when the piston is at the top of its stroke in the cylinder, the gas therein has the smallest volume. The former is called the total volume of the cylinder, while the latter is called the combustion chamber volume of the cylinder. The compression ratio equals the total volume of the cylinder divided by the combustion chamber volume. The compression ratio is an important indicator of an internal combustion engine, wherein a larger compression ratio would result in a larger cylinder pressure and a higher temperature.
[0003] Theoretically speaking, the higher the compression ratio is, the higher the efficiency of an engine will be.
[0004] The compression ratio of a gasoline engine is usually 4-6. The compression ratio of the gasoline engine of a passenger car is increased to 7-9.5 in order to acquire a higher volume/power ratio. The compression ratio of the gasoline engine of a high-end passenger car is said to have reached 12.5. High octane (high grade) gasoline shall be used in a gasoline engine with a high compression ratio. Otherwise, spontaneous combustion would arise in the cylinder during the movement of the engine, such that a knocking would be caused therein.
[0005] The compression ratio of a diesel engine is usually 15-18, such that the thermal efficiency of a diesel engine is 30% higher than that of a gasoline engine. The greenhouse effect brought about by the emission of a diesel engine is 45% lower than that by a gasoline engine. The emission of carbon monoxide and hydrocarbons of a diesel engine is also lower than that of a gasoline engine. A diesel engine adopts compression ignition. Therefore, no knocking problems exist therein. The compression ratio of a diesel engine cannot be too large though, due to limitation of the strength of material.
2. The Octane Rating and Knocking of Gasoline
[0006] Regular gasoline types (research) in the market include unleaded gasoline 90#, 93#, 95#, 97# and 98#. Gasoline 100# is said to exist in some places. The so-called 90#, 93# and 97# are content indicators of “octane rating” of the corresponding gasoline, respectively equivalent to 90%, 93% and 97% of “isooctane” highly capable of anti-knocking and 10%, 7% and 3% of “n-heptane” poor of anti-knocking. Therefore, the octane rating of the gasoline required by an engine becomes an indicator of the anti-knocking capability of the gasoline engine. If gasoline 90# is used where gasoline 97# is required, it would easily bring about a knocking.
[0007] Two methods are usually adopted in evaluating the anti-knocking property of fuel oil, namely motor octane rating and research octane rating. When the motor octane rating of fuel oil is 85, its research octane rating should be 92; when the motor octane rating is 90, its research octane rating should be 97. The octane ratings in this disclosure are all research octane ratings.
[0008] A regular type of gasoline has an octane rating larger than 90 and a relatively high ignition temperature, such that it cannot be normally ignited by compression ignition. Therefore, the gasoline engines nowadays are all spark ignition engines.
[0009] In order to improve the thermal efficiency of a gasoline engine and to avoid a knocking, gasoline producers are trying every means to increase the octane rating of gasoline. Therefore, the production of gasoline is increasingly complex and costly.
3. Low Octane Gasoline
[0010] In order to further improve the compression ratio, thus to improve the efficiency of gasoline engines, the concepts of low octane gasoline and compression ignition low octane gasoline engines are proposed. The operation principle of compression ignition low octane gasoline engines is similar with that of diesel engines. When low octane gasoline is sprayed into the compressed air having a high temperature and a high pressure in the cylinder, ignition and combustion automatically arise therein. Compression ignition low octane gasoline engines may have a higher compression ratio and therefore, a higher thermal efficiency and a smaller greenhouse effect than spark ignition engines.
[0011] Low octane gasoline is defined in the same manner as high octane gasoline. Low octane gasoline graded as gasoline 40#, 30# or 20# respectively comprises 40%, 30% or 20% of “isooctane” having high anti-knocking capability and 60%, 70% or 80% of “n-heptane” having low anti-knocking capability. Low octane gasoline can be graded as gasoline 42#, 33#, 0# or −10#, etc. as required.
[0012] Low octane gasoline is characterized by two aspects. On the one hand, compared with the currently used gasoline, this new low octane gasoline is capable of compression ignition. On the other hand, the fractions of this new low octane gasoline are close or similar to those of the currently used gasoline, which are generally in the range of C7-C11 and can be extended to C6-C12 or even C5-C19 when required.
[0013] For the sake of convenient distinction, in this description, gasoline with the octane rating lower than 50 is referred to as low octane gasoline and that with the octane rating higher than 90 (commonly used at present) is referred to as high octane gasoline.
4. Low Octane Gasoline Engines
[0014] Low octane gasoline engines have the advantages of both diesel engines and gasoline engines. Especially when the compression ratio is selected as within the range of 10-15, low octane gasoline engines have the advantages of gasoline engines as “a small size, small vibration and stable operation”, and the advantages of diesel engines as “high efficiency, high power and a small greenhouse effect resulted by emissions”.
[0015] With respect to compression ignition gasoline engines, a smaller octane rating of the gasoline may require a smaller compression ratio (ranging from 10-15, or 7-22) and lower mechanical strength, and lead to a lighter and handier structure and more gently and smoother operation. Generally speaking, even when the compression ratio of a compression ignition low octane gasoline engine is a very low, it should be still higher than the ratio of a spark ignition gasoline engine. Therefore, a compression ignition low octane gasoline engine has higher thermal efficiency and a small green house effect resulted from emissions.
[0016] Low octane gasoline has shorter carbon chains and is more easily to burn. Therefore, there are few black granular impurities (black smoke) in the exhaust of a low octane gasoline engine. Tests have proved that when low octane gasoline is applied in an engine with the compression ratio of 18, there will hardly be any black smoke in the exhaust.
[0017] The corresponding minimum compression ratios of low octane gasoline of different octane ratings can be obtained by conventional experimental methods (the methods of measuring octane ratings) which are familiar to one skilled in the art.
5. Table 1 Shows the Octane Ratings and Boiling Points of Some Hydrocarbons.
[0018]
[0000]
TABLE 1
The relation between hydrocarbon structures
and octane ratings and boiling points
Boiling
point
Octane
Name
Chemical formula
(° C.)
rating
n-tetradecane
CH 3 —(CH 2 ) 12 —CH 3
252-254
<−45
n-tridecane
CH 3 —(CH 2 ) 11 —CH 3
234
<−45
n-dodecane
CH 3 —(CH 2 ) 10 —CH 3
216.3
<−45
n-undecane
CH 3 —(CH 2 ) 9 —CH 3
196
<−45
n-decane
CH 3 —(CH 2 ) 8 —CH 3
174
<−45
nonane
CH 3 —(CH 2 ) 7 —CH 3
150.8
−45
n-octane
CH 3 —(CH 2 ) 6 —CH 3
125.7
−17
n-heptane
CH 3 —(CH 2 ) 5 —CH 3
98.5
0
n-hexane
CH 3 —(CH 2 ) 4 —CH 3
68.7
25
octene-1
CH 2 ═CH—(CH 2 ) 5 —CH 3
121.3
34.7
ethylcyclohexane
CH 3 —CH 2 —(C 6 H 11 )
131.8
44
pentane
CH 3 —(CH 2 ) 3 —CH 3
36
61
1,1-
CH 3 —(C 6 H 10 )—CH 3
119.5
62
dimethylcyclohexane
octene-4
CH 3 —(CH 2 ) 2 —CH═
74.3
CH—(CH 2 ) 2 —CH 3
cyclohexane
C 6 H 12
80.2
77
hexene-1
CH 2 ═CH—(CH 2 ) 3 —CH 3
63.3
80
ethylbenzene
C 6 H 5 —C 2 H 5
136.2
98
isooctane
(CH 3 ) 3 C—CH 2 —CH(CH 3 ) 2
99.2
100
dimethylbenzene
CH 3 —(C 6 H 4 )—CH 3
138.35-
103
144.42
methylbenzene
C 6 H 5 —CH 3
110.6
104
benzene
C 6 H 6
80.1
108
6. Oil Refining
[0019] Crude oil is a black liquid, known as oil. This liquid contains aliphatic hydrocarbons, or hydrocarbons consisting of only hydrogen and carbon, wherein carbon atoms are linked together to form carbon chains of different lengths.
[0020] Currently, the process of oil refining mainly includes atmospheric distillation, reduced pressure distillation, hydrocracking, catalytic cracking, residual oil cracking, etc., wherein the light components of oil (light oil) are distilled off and the heavy components (long-chain alkanes and long-chain unsaturated hydrocarbons) are first converted into light components and then distilled off. In the distillation of light components, gasoline, aviation gasoline (aviation kerosene), kerosene and diesel are extracted in different stages based on the different condensation points or actually the different boiling points of each component of the light oil. The raw material for chemical products, i.e., “chemical light oil”, also known as “naphtha” can also be extracted within a certain condensation point range according to the different functions of the light oil.
[0021] To improve the octane rating of gasoline, oil refining processes further comprise reforming, catalytic cracking, etc., wherein straight-chain paraffins with low octane ratings are converted into aromatics with high octane ratings. The light oil obtained by these processes also needs to be treated through the process of distillation or rectification, wherein gasoline, kerosene and diesel are respectively extracted in different stages based on their different condensation points.
7. The Innovative Methods of the Present Invention
[0022] In the distillation process according to the prior art, the products of gasoline, kerosene, diesel, etc. are produced by extracting the corresponding components within different ranges of condensation temperatures. Generally, one fraction corresponds to one product. In the present invention, however, different components are respectively extracted by “fixed-point extraction” based on the octane rating of each of the light oil component. Dependent on the principle that one component corresponds to one fraction extraction point, the components of different structures are extracted separately. After that, the components with low octane ratings are combined to prepare low octane gasoline products and the components with high octane ratings are combined to prepare high octane gasoline products. This method has neither been applied in the industry nor been reported of any research so far.
SUMMARY OF THE INVENTION
I. Technical Measures
[0023] In the process of oil rectification or light oil (e.g. naphtha, reformate oil, oil generated from catalytic (hydrogenating) cracking, pyrolysis oil or aromatic raffinate oil) atmospheric distillation or reduced pressure distillation, the extraction points of the distillates are finely divided such that the temperature range of the fractions is narrowed down. Each of the low octane gasoline and high octane gasoline components having a high content from C6-C12 is extracted separately in the order of content. After that, the low octane rating components are combined into compression low octane gasoline products and high octane rating components are combined into high octane gasoline products. The remaining fractions from C6-C12 are added as supplementing agents into the low octane gasoline or high octane gasoline based on the octane ratings thereof “Components having a high content” refer to the first 30 components from the highest to the lowest content sequence or those whose content accounts for 90% of the oil.
[0024] Alternatively, the components from the range of C5-C12 are separately extracted to prepare low octane gasoline products or high octane gasoline products dependent on the octane ratings of these components and the octane rating of the target products. The low octane gasoline products and high octane gasoline products are respectively used as the fuel of compression gasoline engines and spark ignition gasoline engines.
[0025] Those components that are not main components and those fractions that are not separately extracted are also respectively added into low octane gasoline products or high octane gasoline products according to their octane ratings. Those components or fractions unsuitable to be used as gasoline components, e.g. olefins, alkynes and benzene, serve other functions.
[0026] When the octane rating of low octane gasoline is not low enough, low octane fractions of long carbon chains with more than 12 carbon atoms can be added to reduce the octane rating thereof. The octane ratings of paraffins with more than 12 or 13 carbon atoms are relatively low even when they are not straight-chain paraffins. Accordingly, it is an effective measure to add long-chain paraffins to reduce the octane rating of gasoline.
[0027] As to those components whose boiling points are close to each other (e.g. n-heptane and isooctane), and therefore cannot be simply separated through rectification, they can be extracted together as a mixture through rectification firstly, and then be further separated from each other through other means.
[0028] Obviously, the boiling points of the components that are added into low octane gasoline and high octane gasoline are discrete. Differently, in the rectification process of the prior art, diesel, kerosene, aviation kerosene and gasoline are successively extracted according to their temperatures in a descending order, wherein the boiling point temperatures within each product (fraction) is continuous.
[0029] The boiling point of pentane is 36° C. and the octane rating thereof is 61. Pentane generally does not serve as a component of gasoline (high octane gasoline). However, in the seasons when the temperature is low (e.g. winter or in the environment where the temperature is below 15° C.), as a low octane gasoline component, pentane can be added into low octane gasoline as a component of the new gasoline fuel. Hexane can also be used as the raw material to prepare low octane gasoline.
II. Technical Problems to be Solved
[0030] 1. The problems of finely separating, separately distracting and selecting gasoline component are solved.
[0031] 2. The problems of high energy consumption, high cost and lack of resources in producing high octane gasoline (gasoline 90# or that with a larger rating) currently are solved.
[0032] 3. The problem that the octane rating of low octane gasoline is not low enough is solved.
[0033] 4. The technical problem in separating n-heptane and isooctane is solved.
[0034] 5. The problem that pentane or hexane cannot be used as gasoline fuel because of too low an octane rating is solved.
III. The Effects that are Brought about
[0035] 1. Low octane gasoline can be obtained at a low cost, such that low-cost fuel can be provided to efficient, environmentally friendly and low-emission compression low octane gasoline engines.
[0036] Low octane components of gasoline have been a drag and burden to gasoline producers. However, it turns into a treasure now, because low octane gasoline is a low-cost, clean, environmentally friendly and high-quality fuel for internal combustion engines.
[0037] 2. Not only low-cost low octane gasoline, but also low-cost high octane gasoline is obtained. The production process of gasoline is simplified, the raw material for producing gasoline becomes easier to obtain and the production structure becomes simpler and the cost lower.
[0038] For quite a long time, gasoline producers are trying to improve the octane ratings of gasoline, e.g. by the processes of reforming, catalytic cracking, etc., which has increased the cost and energy consumption in producing gasoline products. In order to improve the octane rating of gasoline, even antiknock agents such as MBTE, MMT, etc. are added into the gasoline, which decreases the environment friendliness of the gasoline products and increases harmful components in gasoline and the combustion exhaust thereof.
[0039] 3. Compared with the prior art, the present invention can obtain high octane gasoline and low octane gasoline merely by separating the component of each fraction of the crude oil. The components need not to be converted from one to another such that the present invention provides a comparatively natural, simple, low-cost and environmentally friendly method.
DETAILED DESCRIPTION OF EMBODIMENTS
I. General Embodiments
[0040] 1. The components of the raw material (oil or light oil) to be processed (distillation) are first of all analyzed and tested and then extracted respectively (separately) from the raw material according to their boiling points (as shown in Table 1) in the process of the distillation. The components are then combined in various manners (mixed) dependent upon their octane ratings and according to the octane rating indexes of the target products, wherein low-octane gasoline products and high octane gasoline products are respectively obtained. For example, dimethylbenzene, isooctane, ethylbenzene, hexene-1, etc. are used to prepare gasoline 97#, gasoline 93# or other high octane gasoline; n-undecane, n-decane, nonane, n-octane, n-heptane, n-hexane, octene-1, ethylcyclohexane, etc. are used to prepare gasoline 35#, gasoline 0# or other low octane gasoline; and cyclohexane, octene-4, 1,1-dimethylcyclohexane, etc. can be added into high octane or low octane gasoline as required or permitted.
[0041] Fixed-point extraction method: when 10 main components in the raw material for distillation are to be extracted by fixed-point extraction, 10 small distillation columns can be suspended outside the main distillation column, the temperatures at the top of the 10 small distillation columns being controlled as the boiling points of the corresponding components. Other distillates than those of the 10 components return to the main column and are distilled off from other ports thereof.
[0042] 2. C12-C14 (or even longer-chain alkenes, such as C12-C14 alkenes) components can be added into low octane gasoline as required. In this case, the octane ratings of other components in the low octane gasoline can be appropriately increased, e.g. ethylcyclohexane, pentane, 1, 1-dimethylcyclohexane, and even octene-4 and cyclohexane can all serve as a component of low octane gasoline.
[0043] 3. The components that are not listed out in Table 1 are respectively allocated and added into high octane gasoline or low octane gasoline dependent on the octane ratings of the components.
[0044] 4. The separation of n-heptane and isooctane:
[0045] Because the boiling points of n-heptane (98.5° C.) and isooctane (99.2° C.) are approximately close to each other, they are difficult to be separated by atmospheric distillation or reduced pressure distillation. In the present invention, these two components are first of all simultaneously extracted (e.g. by atmospheric distillation of the fractions in the range of 92-105° C.) and then separated by gas adsorption or azeotropic distillation. N-heptane is then used in the preparation of low octane gasoline and isooctane in the preparation of high octane gasoline.
[0046] In the industrial production, 5 A molecular sieves are usually adopted as an adsorbent of straight-chain paraffins such as n-heptane and steam is usually used as a desorbent, such that n-heptane can be extracted and separated from isooctane.
[0047] In the industrial production, methanol is usually adopted as an entrainer of n-heptane to separate and extract n-heptane, such that n-heptane and isooctane can be separated.
[0048] Currently, it is not known how to separate n-heptane and isooctane from each other in the oil refining industry. Therefore, the separation technique mentioned above is one of the innovations of the present invention.
[0049] Through separation of n-heptane and isooctane, a high octane component with the octane rating as 100 and a low octane component with the octane rating as 0 will be simultaneously obtained, which would be an important contribute to the joint production low octane gasoline and high octane gasoline of the present invention.
II. Simplified Embodiments
[0050] 1. In order to reduce the complexity of the process of “fixed-point extraction” (separate extraction) from the light oil, some extraction points can be omitted according to the actual situation, such that the distillation fraction extraction points can be reduced, e.g. the number of the “components with a high content” can be reduced from 30 to 28, 24 or 20, etc.
[0051] 2. The remaining fractions other than those which are extracted “separately” can be respectively extracted together with either of the two adjacent components in the extraction temperature sequence in accordance with the principle of proximity of octane ratings.
[0052] For example, among all the components in the range of C7-C11, suppose the content number of a component is 31, whose octane rating is 34.7 and whose boiling point is 121.3° C.; the extraction point and octane rating of its high temperature adjacent fraction are respectively 131.8° C. and 44, and those of its low temperature adjacent fraction are respectively 119.5° C. and 62. In this case, this component will be extracted together with the fraction whose extraction point is 131.8° C., because their octane ratings (respectively 34.7 and 44) are 9.3 points away from each other, which is smaller than the distance between 34.7 and 62 (i.e., 27.3).
[0053] 3. Dimethylbenzene comprises three isomers, whose boiling points and octane ratings are close to one another, such that they can be extracted as a fraction and serve as a mixture component of high octane gasoline.
[0054] 4. Dimethylbenzene and ethylbenzene can be extracted as a fraction and serve as a component of high octane gasoline.
[0055] 5. Methylbenzene, dimethylbenzene and ethylbenzene can be extracted as a fraction and serve as a component of high octane gasoline.
[0056] 6. Fraction extraction points are uniformly provided at a small interval on the distillation column of oil or light oil. For example, fraction extraction ports are provided at an interval of 1° C. (or 2° C., 0.5° C. or other temperatures) to collect the fractions of different condensation points. The light oil composition or octane rating of each fraction is tested (analyzed) and the fractions are used in the preparation of low octane gasoline or high octane gasoline or to serve other functions according to their octane ratings. As to fractions of complex compositions (e.g. the mixture fraction of n-heptane and isooctane), a secondary separation can be carried out by other methods where necessary. Although the above-mentioned method seems far from satisfactory and requires complex distillation equipment, it excels in simple production organization and good adaptability to different sources of raw materials.
[0057] For components with specific boiling points where a decimal place is included (e.g. the boiling point of 1, 1-dimethylcyclohexane is 119.5° C. and that of n-octane is 126.7° C.), fraction extraction points at the temperature positions calculated to one decimal place are provided on the distillation column (fraction collection points are provided respectively at the temperature positions of 119.5° C. and 126.7° C.).
[0058] As experience accumulated, most fractions can be transported through the pipeline directly to the low octane gasoline tank or the high octane gasoline tank.
[0059] 7. As to the remaining portion after the process of rectification extraction (fixed-point extraction), it is divided into two parts dependent upon the boiling points of the fractions. Generally, fractions of high temperatures enter into low octane gasoline while fractions of low temperatures enter into high octane gasoline, which, however, is merely an empirical approach. Whether the fractions or how much of the fractions enter into the gasoline with corresponding octane ratings should be determined according to the test result of the octane ratings as actually required.
III. Supplementary Explanations
[0060] 1. In producing high octane gasoline with the method of the present invention, anti-knock agents may not be added to the maximum extent. Generally speaking, it is neither economy nor environmentally friendly to add anti-knock agents into gasoline.
[0061] 2. In this disclosure, only the technical solutions in producing high octane gasoline and low octane gasoline are provided. Where the issue of safety or environment protection is concerned with respect to the relevant components of gasoline products, the gasoline product standards of local authorities should be observed.
[0062] 3. No creative work is involved in preparing different grades of gasoline with addition of fractions of different octane ratings.
[0063] 4. The present invention does not exclude the method of adding ethanol or antiknock agents such as MBET, MMT, etc. in high octane gasoline products. On condition that the octane standard is measured up, low octane gasoline can be mixed with ethanol to serve as a mixture fuel.
[0064] 5. In the rectification extraction methods such as “fixed-point extraction” or “separate extraction” recited in this disclosure, the extracted component may not be pure. However, this method is a success as long as most of the target component is extracted, and among the actually extracted components, the target component accounts for the most part. As the extraction techniques are improved, e.g. the theoretical increase of column plates and the increasingly narrowing of the boiling point range of the rectification extracts, the content of the target component (concentration) obtained by the present method (fixed-point extraction or separate extraction) in each extraction component will be increasingly high.
[0065] 6. The pressure can be reduced or the theoretical column plates can be increased in order to separate n-heptane and isooctane.
[0066] 7. A liquid adsorption method is adopted to separate isooctane and n-heptane. The liquid adsorption separation method is a frequently-used industrial production method, e.g. paraxylene (PX) is extracted from the mixture of dimethylbenzene mainly by this method. The design and production of an adsorbent belongs to a professional technical field, wherein the adsorbent required in the separation of n-heptane and isooctane can be conveniently provided. The adsorbent according to this method can be sued to adsorb either n-heptane or isooctane. The adsorbent technique itself is not included in the claims of the present invention. | The present invention relates to a method for joint production of low octane gasoline and high octane gasoline. In the process of oil or light oil rectification, the extraction points of the distillates therein are finely divided, and the temperature ranges for extraction of fractions are narrowed down. Each of the low and high octane components having a high content in the range from C6-C12 (which may be extended to C5-C14 where necessary) is then separately extracted. After that, low octane components are combined into compression ignition low octane gasoline products, while high octane components are combined into high octane gasoline products. The remaining fractions are respectively added as supplementing agents into the low octane gasoline products or high octane gasoline products dependent on their octane ratings. Low octane gasoline is used in compression ignition gasoline engines, while high octane gasoline is used in spark ignition gasoline engines. | 2 |
TECHNICAL FIELD
This invention relates in general to secondary lithium electrochemical cells, and more particularly to secondary lithium batteries having high capacity positive electrodes.
BACKGROUND OF THE INVENTION
Secondary lithium electrochemical cells, and particularly lithium batteries, using an intercalation compound as the positive electrode, or cathode of the battery have been studied intensely during the past decade. Heretofore, the cathode material used in these batteries was typically a lithiated cobalt oxide, nickel oxide, or manganese oxide. Lithiated transition metal oxide batteries are being studied as an alternative to current nickel-cadmium and nickel-metal hydride cells because they possess several attractive characteristics, e.g., high cell voltage, long shelf life, a wide operating temperature range, and use of non-toxic materials. The earliest reports of LiNiO 2 and LiCoO 2 as the positive electrode materials in rechargeable lithium batteries occurred more than a decade ago and are shown in, for example, U.S. Pat. Nos. 4,302,518 and 4,357,215 to Goodenough, et al.
These materials have been intensively investigated, and one of them, LiCoO 2 is currently used in commercial lithium ion batteries. Numerous patents have been issued for different improvements in these materials as the positive electrode for lithium cells. An example of a recent improvement is illustrated in U.S. Pat. No. 5,180,547 to Von Sacken for "HYDRIDES OF LITHIATED NICKEL DIOXIDE AND SECONDARY CELLS PREPARED THEREFROM". The Von Sacken reference teaches fabricating the hydroxides of lithium nickel dioxide fabricated in an atmosphere including a partial pressure of water vapor greater than about 2 torr.
Regardless of the particular material used in such cells, each material is synthesized in an oxidizing environment such as O 2 or air at temperatures higher than about 700° C. using nickel or cobalt and lithium containing salts. For example, a publication to Ohzuku, et al published in the Journal of the Electrochemical Society, Vol. 140, No. 7, Jul. 19, 1993, illustrates at Table 1 thereof, the typical processing methods for preparing LiNiO 2 . Each of the methods illustrated in the Ohzuku, et al reference show preparing the material in an oxidizing environment of either oxygen or air.
Charge and discharge of the materials fabricated according to these processes proceeds by a charge mechanism of de-intercalation and intercalation of lithium ions from and into these materials. The materials synthesized by the prior art methods have a reversible capacity of about 135 mAh/g. In other words, about 0.5 lithium ions can be reversibly deintercalated and intercalated from and into each mole of LiNiO 2 or LiCoO 2 .
A significant amount of the capacity of these materials resides at potentials higher than about 4.2 volts versus lithium. If more than 0.5 lithium ions is removed from each of either a LiNiO 2 or LiCoO 2 electrode, potentials higher than 4.2 volts versus lithium are required causing decomposition of most electrolytes. Further, removal of more than 0.5 lithium ions will result in irreversible changes in the structure of these materials, causing a decrease in their capacity during charge and discharge cycles. This result was reported in a publication by Xie, et al prepared at the Electrochemical Society Fall Meeting, 1994, Extended Abstract No. 102, Miami, October 1994.
The reversible capacities of the most commonly used materials synthesized in O 2 and air atmospheres are very sensitive to residual inactive lithium salts such as Li 2 O, LiOH, and LiCoO 3 , each of which result from the synthesis process. However, to make stoichiometric LiNiO 2 , which is perceived to have the best performance of any of the prior art materials, excess lithium salt is normally used in precursor materials. As a result, the presence of residual lithium salt is inevitable in the final product fabricated according to prior art methods. In addition to causing a decrease in the capacity of LiNiO 2 , the presence of residual lithium salts often causes gas evolution such as CO 2 , H 2 and O 2 at the positive electrode during charging. Further, it is normally observed that the initial charge efficiency is much lower for LiNiO 2 (i.e., less than about 80%) than that for LiCoO 2 when the two materials are made in a similar fashion. In order to reduce these problems, manufacturers typically try to minimize or eliminate residual lithium salts from the product.
Accordingly, there exists a need to develop a new cathode material for rechargeable electrochemical systems, which is fabricated of materials which are relatively environmentally friendly, may be fabricated at relatively low temperatures and which demonstrate performance characteristics superior to those of the prior art. Specifically, such materials should have: (1) high capacity greater than 170 mAh/g at potentials between 3.5 and 4.2 volts; (2) an easy synthesis process which can be highly controlled; (3) insensitivity to residual lithium salts; (4) high initial charge efficiency; and (5) high reversible charge/discharge reactions so as to provide a material having good cycle life.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of an electrochemical cell including an electrode in accordance with the instant invention;
FIG. 2 is a flow chart illustrating the steps for preparing a lithiated transition metal oxide material in accordance with the instant invention;
FIG. 3 is an x-ray diffraction pattern of a high capacity LiNiO 2 material fabricated in accordance with the instant invention;
FIG. 4 is a charge/discharge profile for a high capacity LiNiO 2 material in accordance with the instant invention; and
FIG. 5 is a chart illustrating the discharge capacity and charge efficiency of an electrochemical cell employing a positive electrode material in accordance with the instant invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward.
Referring now to FIG. 1, there is illustrated therein a schematic representation of an electrochemical cell 10 including a lithiated transition metal oxide electrode in accordance with the instant invention. The electrochemical cell includes a positive electrode 20 and a negative electrode 30 and has an electrolyte 40 disposed between said electrodes. The cell 10 further includes a positive electrode 20 fabricated of a transition metal oxide such as a nickel oxide or a cobalt oxide electrochemical charge storage material which is described in greater detail hereinbelow. The negative electrode 30 or anode of the cell 10 may be fabricated of materials selected from the group of materials consisting of, but not limited to, Li metal, Li alloying metals such as Al, Sn, Bi, carbon (including graphite and petroleum coke), low voltage Li intercalation compounds, such as TiS 2 , V 6 O 13 , MoS 2 , and combinations thereof. The electrolyte 40 disposed between the electrodes can be any of the electrolytes known in the art, including, for example, LiClO 4 in propylene carbonate or polyethylene oxide, impregnated with a lithiated salt. The electrolyte may be either a solid, gel, or aqueous electrolyte. The electrolyte 40 may also act as a separator between the positive and negative electrodes.
In accordance with the instant invention, there is provided a method for fabricating a lithiated transition metal oxide material which is capable of storing and discharging electrical charge. The material disclosed herein is therefore useful as, for example, the cathode in lithium rechargeable batteries. The stabilized material has the formula LiTMyO 2 .Li 2 O where TM is a transition metal selected from the group of Mn, Ni, Co, and combinations thereof; 0.05≦x≦1.0; y≧1.0; and where Li 2 O may exist as a separate phase. The valence state of the TM may be less than the 3+ state. It is to be noted that Li 2 O may be tolerated in the instant material, and does not cause the deleterious effects observed in the prior art lithiated transition metal oxide cathode materials. The material may further include one or more modifiers selected from the group of Ti, Bi, Fe, Zn, Cr, and combinations thereof.
Referring now to FIG. 2, there is illustrated therein a flowchart 50 describing the steps for preparing a lithiated transition metal oxide material in accordance with the instant invention. The first step in preparing the lithiated transition metal oxide material is illustrated in Box 52 of Flowchart 50. Box 52 recites the step of providing a transition metal precursor material. Precursor materials which may be used include, for example, first transition metal compounds such as TM(OH) 2 , TMO, TM(NO 3 ) 2 , and TM(CO 2 ) where TM is a first transition metal, such as Co, Ni, or Mn. Specific examples of materials include, Ni(OH) 2 , Ni(NO 3 ) 2 .6H 2 O, NiO, Co(OH) 2 .Co(NO 3 ) 2 .6H 2 O, CoO, MnO, Mn(OH) 2 , Mn(NO 3 ) 2 .6H 2 O, Mn 2 O 3 , and combinations thereof. In one preferred embodiment, the transition metal precursor material is Ni(OH) 2 . In a second preferred embodiment, the transition metal precursor material is Co(OH) 2 .
The second step illustrated in Flowchart 50 is shown in Box 54 and comprises the step of providing a lithium containing compound. Examples of lithium-containing compounds include, for example, LiNO 3 , LiOH, Li 2 O, Li hydrocarbonate salts and combinations thereof. It is to be understood that in selecting the first transition metal precursor material and the lithium containing material, at least one of the them must include an oxidizing group, such as NO 3- to provide an oxidizing agent for the reaction. In one preferred embodiment, the transition metal precursor material is TM(OH) 2 , such as Ni(OH) 2 , and the lithium containing material is LiNO 3 , providing the required NO 3- oxidizing agent. Thus, the reaction for this preferred combination is as follows: ##STR1## This combination is preferred because the transition metal hydroxide has a layered structure, and both Ni(OH) 2 +LiNO 3 can mix homogeneously, as LiNO 3 becomes liquids at temperatures above 260° C. Further, Ni(OH) 2 has a crystalline structure similar to that of LiNiO 2 (a layered structure) and does not go through a NiO phase before forming LiNiO 2 . The transition metal precursor material and the lithium-containing compound are mixed together via conventional mixing techniques such as, for example, ball milling. This step is illustrated in Box 56 of Flowchart 50.
Thereafter, the materials are reacted, as by heating as illustrated in Box 58 of Flowchart 50. The conditions and environment in which the heating takes place is critical to forming a material having high capacity as illustrated herein. More particularly, the mixed materials are heated in an inert environment. By an inert environment, it is meant that the principle components of the atmosphere in which the heating takes place are not reactive with the materials therein. Accordingly, the heating illustrated in Step 58 of Flowchart 50 is carried out in a helium, nitrogen or argon environment. In one preferred embodiment, the heating generates reaction conditions, and takes place in a N 2 atmosphere, at temperatures between about 500° C.-800° C., and preferably between 600° C.-700° C. Heating continues for at least four and preferably at least ten hours. This is a substantial departure from the prior art which uniformly teaches the use of an oxidizing element to facilitate the activity of the oxidizing agent. Indeed, the prior art teaches away from any nonoxidizing environment.
There is an optimal reaction time for each temperature and for different ratios of Ni 2+ to Li + in the starting materials. The optimal reaction time can be determined by examining x-ray diffraction patterns of resulting materials. Specifically, the novel material resulting from the process described in FIG. 2 can be identified by its unique powder x-ray diffraction ("XRD") pattern. Specifically, the XRD pattern for a high capacity LiNiO 2 .0.7Li 2 O material in accordance with the instant invention is shown in FIG. 3. The XRD pattern has several peaks illustrated therein, though only two, identified as 70 and 72, are examined herein.
Peak 70 corresponds to an x-ray diffraction intensity at the degrees 2θ angle of approximately 18.7°, using CuKα 1 as the x-ray source. Peak 72 corresponds to the x-ray diffraction intensity at the degrees 2θ of approximately 44.2°, again using a CuKα 1 x-ray source. XRD patterns of prior art materials demonstrate a ratio between these peaks of no more than 1.40:1.00, and typically about 1.1:1.0. Conversely, the signature ratio of the instant high capacity material is at least 1.60:1.0 and may be considerably higher. This ratio is demonstrated in FIG. 3.
Accordingly, and contrary to the state of the art methods disclosed in the prior art, the synthesis of LiNiO 2 or LiCoO 2 can be accomplished through melt-solid reaction using an NO -3 containing salt as the oxidizing agent in an inert environment such as helium or nitrogen at temperatures below 700° C. Materials made in an inert environment have higher reversible capacity and charge efficiency than those made by the conventional method, i.e., in air or oxygen. Further, the reversibility of the intercalation/deintercalation of these materials is better, as will be demonstrated hereinbelow.
The materials fabricated in accordance with the method described herein, demonstrates distinct differences in defined structures of XRD patterns, as described above. In addition to the differences illustrated in FIG. 3, materials fabricated according to the instant invention have a significantly different physical appearance as compared with conventional materials. Materials fabricated according to the instant invention have a deep black color, such as carbon black, and have a "slippery" consistency similar to that of graphite powder. Conversely, materials according to the prior art are gray in color and do not possess the "slippery" graphite-like feeling.
The invention may be better understood from the examples presented below:
EXAMPLES
Examples I
A lithiated transition metal oxide material was prepared in accordance with the instant invention. Ni(OH) 2 and LiNO 3 were provided in the molar ratio of 1.0:2.5, and mixed thoroughly in a ball mixer and pressed into a pellet. Thereafter the pellet was heated to 300° C. in helium for four hours, heated to 600° C. for 20 hours in helium, with two intermittent grinding and heating steps. The weight of the resulting product was consistent with LiNiO 2 .0.75Li 2 O. An XRD analysis of the material was conducted on the material and is illustrated in FIG. 3 described hereinabove. The XRD pattern of the material indicates that it contained LiNiO 2 and Li 2 O only.
The electrochemical behavior of the material fabricated according to this example was evaluated in a test cell with 1M LiPF 6 in a solution of 50% ethylene carbonate and 50% dimethylethylene as the electrolyte and a lithium metal foil as the negative electrode (anode). The charge and discharge profiles of the cell voltage of the cell fabricated accordingly to this Example I is illustrated in FIG. 4 hereof. More specifically, it may be appreciated from FIG. 4, that nearly one lithium ion may be removed from each LiNiO 2 on charging at potentials below 4.2 volts and that approximately 0.9 lithium ion can be intercalated into the material for each nickel atom on discharge at a potential higher than about 3.0 volts.
It should be pointed out here that this material has the following characteristics that are different from those synthesized by a prior art method: 1. The peak ratio of the XRD intensity at the 2θ angle of about 18.7° to that at 44.3° is greater than 1.6 as illustrated in FIG. 3, compared to less than 1.4 for those by a prior art method; 2. the existence of Li 2 O does not affect the charge and discharge capacity; and 3. there is a flat plateau near 4.2 on charge and a corresponding one on discharge for this material as illustrated at points 80 and 82 respectively in FIG. 4. No plateau is observed on the charge curve at this potential for materials synthesized by a prior art method.
Referring now to FIG. 5, there is illustrated therein the discharge capacity (line 84) and the charge efficiency (line 86) as a function of cycle life for a coin type cell using a lithiated nickel oxide material fabricated in accordance with the instant invention, as described in this Example I. The lithiated nickel oxide served as the positive electrode material and commercially available graphite was used as the negative material. The separator used in the cell was porous polypropylene and is commercially available under the name Celgard 2500®. The electrolyte used in the cell was 1M LiPF 6 in a mixture of ethylene carbonate, diethylene carbonate, and propylene carbonate. The cell was charged and discharged at a rate of about C/3. The mass ratio of the positive electrode material to the negative electrode material was approximately 2:1. As shown in FIG. 5, the capacity of the cell does not fade with increasing cycle number.
Example II
Ni(OH) 2 and LiNO 3 were provided in the molar ratio of 1:1.05 and ground and mixed in a ball mill. The mixture was heated to 300° C. in air for 8 hours and then at 600° C. in air for 40 hours. The resulting product was ground and examined by x-ray diffraction. The XRD patterns indicated that the material consisted of Li 2 Ni 8 O 10 and LiNO 3 , and demonstrated poor electrochemical properties. However, a similar mixture was converted completely into high capacity LiNiO 2 .Li 2 O having a capacity greater than ˜170 mAh/g within 18 hours when calcined in a helium environment at temperatures of 600° C. This example indicates that partial oxidation of Ni 2+ , by O 2 in air slows decomposition of LiNO 3 as in the prior art method. A high capacity LiNiO 2 can be synthesized at a low temperature such as 600° C. in an inert environment, but cannot be made in air or O 2 at the same temperature.
Example III
Co(OH) 2 and LiNO 3 were mixed in the molar ratio of 1:2.5 and ground and mixed in a ball mill. The mixture was heated to 300° C. in helium for 8 hours and then at 600° C. in helium for 20 hours. The resulting product was ground and examined using x-ray diffraction. The XRD patterns indicate that the material contained LiCoO 2 and Li 2 O. The material also showed a capacity in excess of 140 mAh/g.
While the preferred embodiments of the invention have been illustrated and described, it will be clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims. | A method for preparing a lithiated transition metal oxide electrochemical charge storage material for use in an electrochemical cell. The cell (10) includes a cathode (20), an anode (30) and an electrolyte (40) disposed therebetween. The method involves the preparation of the lithiated, transition metal oxide material in an inert environment. The materials are characterized by improved electrochemical performance, and an identifiable x-ray diffraction matter. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to trailer hitches and more specifically, to a trailer hitch mounted to the bumper of a truck or other vehicle and having a rotatable draw plate for selectively deploying the draw plate and companion hitch ball outwardly of the trailer hitch in functional configuration, and inwardly of the trailer hitch housing in retracted, non-functional configuration.
Trailer hitches are conventionally mounted on the bumpers or frames of vehicles such as trucks and cars with a draw bar extending rearwardly of the bumper and a hitch ball bolted or otherwise secured to the pivoting end of the draw bar. When not in use, such hitches constitute a safety hazard and also detract from the esthetics of the vehicle. Since the draw bar and hitch ball extend outwardly from the bumper just below the knee of a person of average height, bumping of the shin and knee area of the legs against the hitch sometimes occurs when walking around the rear of the vehicle. The trailer hitch embodied in this invention includes a rotatable draw plate which operates to selectively extend the hitch ball in functional configuration rearwardly of the vehicle bumper for attachment to a trailer and inwardly of the trailer hitch housing through the plane of the bumper, when not in use.
2. Description of the Prior Art
Various trailer hitch mechanisms are known in the art for recessing or folding the draw bar and hitch ball of a trailer hitch. U.S. Pat. No. 2,474,231, dated June 28, 1949, to R. V. Crosely, discloses a "Sliding Ball Hitch For Automobiles". The sliding ball hitch detailed in this patent is characterized by a casing adapted to be connected to the rear of an automobile and having an opening in the rear end thereof, the casing further provided with interior shoulder portions and a block slidable in and out of the casing through the rear opening. The block is further provided with portions adapted to engage the shoulder portions of the casing, in order to limit outward movement of the block and the block is also provided with a recess having a sloping surface in the upper surface thereof. A latch plate having an upwardly-extending lip on the outer edge is positioned in the recess and a spring is located in the block for urging the plate upwardly to lock the block in the extended position. A ball is connected to the block for connecting the trailer hitch to the hitch device of a trailer. U.S. Pat. No. 3,117,805, dated Jan. 14, 1964, to W. A. Schoeffler, discloses a "Traler Hitch", the rear end section of which is bolted to the vehicle and the front end section being vertically pivotally attached to the rear end section, for rotating the draw bar and hitch ball into and out of functional orientation with respect to the vehicle. Another trailer hitch is disclosed in U.S. Pat. No. 3,480,296, dated Nov. 25, 1969, to E. L. Starling. The trailer hitch detailed in this patent is designed for mounting in a vehicle bumper and includes a draw bar pivotally mounted within a recess in the bumper, for swinging movement between a draft position outwardly extending from the bumper and a position with the draw bar fully retracted within the recess in the bumper to present a clean, uncluttered bumper surface. U.S. Pat. No. 4,109,930, dated Aug. 29, 1978, to S. T. L. Pilhall, discloses a "Towing Device For Motor Vehicles". The towing device embodied in this patent includes an upwardly-directed portion which is shaped as a ball and connected to the bumper and which, in a storage position, is covered by a removable or slidable portion of the bumper. The ball portion is connected to the bumper beam in such a manner that it can be moved between the storage position located in a storage space in the bumper beam and a towing position completely outside of the storage space. A "Hinged Bi-Level Hitch For A Vehicle" is disclosed in U.S. Pat. No. 4,275,899, dated June 30, 1981, to Verle L. Humphrey. This patent details a heavy-duty, hinged bi-level hitch for mounting on a tubular bumper of a vehicle. The hitch includes an upper hitch assembly with an upper hitch ball, which upper hitch assembly is integrally formed in the center of the bumper. A lower hitch assembly is pivotally attached to the bottom of the bumper. The lower hitch assembly can be pivoted from a raised storage position underneath the vehicle to a lowered position directed below the upper hitch assembly by loosening a pair of bolts. U.S. Pat. No. 4,482,167, dated Nov. 13, 1984, to H. L. Haugrud, discloses a "Retractable Hitch". The retractable hitch is designed for attachment beneath the bumper of a vehicle and the tow bar of the hitch is held in a retracted position by a pivotal wall locked in place. Alternatively, the tow bar may be clamped into an operational position by the same pivotal wall locked in place. The retractable hitch is operated into and out of the functional configuration by moving a handle beneath the hitch and rotating the tow bar, as desired. U.S. Pat. No. 4,540,194, dated Sept. 10, 1985, to Roy Dane, discloses a trailer hitch which includes a plate that is adapted to selectively lie flush with the bed of the truck or other vehicle and extend upwardly for attachment to a trailer. A hitch block, which has a connecting ball at one end, is journalled on an axis below the plate in such a manner, that when disposed in the towing position, the ball is located above the plate and when the vehicle is used for hauling, the entire block can be folded down beneath the bed of the vehicle. The opposite end of the block is provided with a spring-biased, retractable pin and an arcuate member located beneath the plate is provided with holes which receive the pin to hold the block in a selected position.
It is an object of this invention to provide a new and improved, heavy-duty trailer hitch having a rotatable draw plate for selectively orienting a hitch ball in functional towing configuration outwardly of the trailer hitch housing and rotating the hitch ball inwardly of the trailer hitch housing when not in use.
Another object of this invention is to provide a new and improved trailer hitch having a rotatable draw plate, which trailer hitch is designed for removably mounting to the bumper of a pick-up truck or other vehicle and is designed to selectively deploy the hitch ball outwardly of the vehicle bumper when in functional configuration and inwardly of the trailer hitch housing and inside the vertical plane of the vehicle bumper when in rotated, non-functional configuration, responsive to manipulation of a latch mechanism and rotation of the draw plate.
Still another object of the invention is to provide a trailer hitch having a rotatable draw plate, the frame of which trailer hitch is mounted on the bumper of a pick-up truck and is operable to locate the hitch ball outwardly of the plane of the bumper for coupling to the hitch mechanism of a trailer and inwardly of the trailer hitch housing and retracted inside the plane of the bumper when not in use.
A still further object of this invention is to provide a new and improved trailer hitch having a rotatable draw plate which is capable of removably receiving hitch balls of varying diameter and wherein a first hitch ball is mounted to the draw plate and a second hitch ball is mounted to the bumper and trailer hitch housing.
Yet another object of the invention is to provide a new and improved trailer hitch having a curved, rotatable draw plate, which trailer hitch is characterized by a housing having a ball clearance opening and is adapted for mounting on the bumper plate of a pick-up truck bumper and is rugged in construction and designed to tow trailers of substantially any size, with the capability of rotatably deploying the hitch ball outwardly of the bumper when in functional configuration and retracting the hitch ball through the ball clearance opening inside the trailer hitch housing when in stored configuration, responsive to manipulation of a latch and rotation of the draw plate with respect to the housing.
SUMMARY OF THE INVENTION
These and other objects of the invention are provided in a new and improved trailer hitch having a rotatable, curved draw plate for bolting to the bumper of a pick-up truck, which trailer hitch includes a latch mechanism for securing and releasing the draw plate and selectively deploying the trailer hitch ball outwardly of the trailer hitch housing in functional configuration and inwardly of the trailer hitch housing through a ball clearance opening, when retracted and not in use.
The invention will be better understood by reference to the accompanying drawing, wherein:
FIG. 1 is a front perspective view of the trailer hitch of this invention oriented in functional configuration for mounting on the bumper plate of a pick-up truck;
FIG. 2 is a bottom perspective view of the trailer hitch illustrated in FIG. 1;
FIG. 3 is a side sectional view of the trailer hitch illustrated in FIG. 1, with the pivot plate deployed in functional configuraton outwardly of the hitch housing;
FIG. 4 is a sectional view of the trailer hitch illustrated in FIG. 1, with the pivot plate rotated such that the hitch ball is located inwardly of the trailer hitch housing;
FIG. 5 is a top view of the pivot plate element of the trailer hitch of this invention; and
FIG. 6 is a perspective view of the trailer hitch illustrated in FIG. 1 mounted in functional configuration on the bumper of a pick-up truck.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIGS. 1, 2, 3 and 6 of the drawings, the trailer hitch of this invention is generally illustrated by reference numeral 1. The trailer hitch 1 includes a frame 1a, having a flat bumper mount plate 2, for securing the trailer hitch 1 to the conventional bumper plate 31 of the bumper 29 in a truck 28, by means of hitch mount bolts 30 and cooperating mount nuts 33. The bumper 29 is mounted on the truck 28 in conventional fashion and the trailer hitch 1 is suspended beneath the bumper plate 21 of the bumper 29 by means of the hitch mount bolts 30 and mount nuts 33, as illustrated. In a most preferred embodiment of the invention, a pair of mount slots 3 are provided in the bumper mount plate 2 in spaced relationship, in order to receive the hitch mount bolts 30 in adjustable fashion and accommodate a wide variety of hole spacings in the bumper plate 31. A ball mount hole 4 is also provided in the bumper mount plate 2 between the mount slots 3, in order to accommodate an auxiliary hitch ball 32, as illustrated in FIG. 6. The frame 1a of the trailer hitch 1 is completed by a pair of curved, downwardly extending side plates 5, one of which side plates 5 is welded or otherwise attached to a curved groove plate 25 and the other of which is secured to a rounded bottom mount plate 13, as illustrated in FIG. 2. The bottom mount plate 13 and the groove plate 25 define a curved clearance groove 24, which exists for a purpose which will be hereinafter further described. In a most preferred embodiment of the invention and referring again to FIG. 1, the bumper mount plate 2 to side plates 5 welds are strengthened by a pair of plate gussets 6 and the bottom edge of one of the side plates 5 is welded to a top mount plate 7, which extends parallel to the bumper mount plate 2. A partition plate 14 projects downwardly from welded attachment to the bumper mount plate 2 and is secured at the bottom edge thereof to the projecting edge of the top mount plate 7, in order to define a latch chamber 8a, provided with a latch 8, as illustrated. A pair of thin plate fillers 16 are welded between the curved top edges of the side plates 5 and the corresponding edges of the bumper mount plate 2, respectively, to strengthen the frame 1a. A ball clearance opening 26 is defined by the downwardly-extending partition plate 14 and the opposite one of the side plates 5 and the ball clearance opening 26 lies adjacent to the latch chamber 8a, as illustrated. The latch 8 provided in the latch chamber 8a is further characterized by a latch bracket 9, the legs of which are welded or otherwise attached to the top mount plate 7 and a t-bar 10, slidably mounted in the horizontal segment of the latch bracket 9. A coil spring 11 is mounted on the t-bar 10 and is disposed between the latch bracket 9 and a spring washer 12, which is welded or otherwise attached to the t-bar 10, in order to spring-load and bias the extending end of the t-bar 10 downwardly through an opening (not illustrated) in the top mount plate 7 and into a corresponding and registering opening 22, provided in the underlying pivot plate 15, and a bottom mount plate opening 13a, located in the bottom mount plate 13. As illustrated in FIG. 5, the pivot plate 15 is rotatably disposed between the spaced top mount plate 7 and bottom mount plate 13 and includes a curved front margin 27 and a pair of spaced spring pin openings 22, a pivot bolt opening 23 and a hitch ball 19. The pivot plate 15 is rotatably attached to the top mount plate 7 and the bottom mount plate 13 by means of a pivot bolt 17, which extends through the pivot bolt opening 23 and corresponding registering openings (not illustrated) drilled in the top mount plate 7 and bottom mount plate 13 and is secured by a cooperating pivot nut 18. The hitch ball 19 is secured to the pivot plate 15 near the front margin 27 of the pivot plate 15 by means of a ball mount nut 21, which is threaded on the ball mount bolt 20, which projects through a companion opening (not illustrated) drilled in the pivot plate 15, as illustrated.
Referring again to FIGS. 1, 3 and 6 of the drawing, the pivot plate 15 is rotatably mounted between the top mount plates 7 and the bottom mount plate 13 on the pivot bolt 17 such that the hitch ball 19 is extended outwardly of the ball clearance opening 26 in functional configuration. When so located, the hitch ball 19 is deployed for attachment to the hitch mechanism of a trailer (not illustrated) in conventional manner.
Referring to FIGS. 1, 2 and 5 of the drawing and as heretofore noted, the pivot plate 15 is rotatably disposed between the spaced top mount plate 7 and bottom mount plate 13 on the pivot bolt 17 by means of the pivot bolt 17. Furthermore, the projecting end of the t-bar 10 extends through a hole (not illustrated) provided in the top mount plate 7 and the spring pin opening 22 which is aligned with the corresponding opening in the top mount plate 7 (not illustrated), and into the bottom mount plate opening 13a, in order to selectively lock the pivot plate 15 in functional configuration as illustrated in FIGS. 1 and 2 and in folded or non-functional configuration, as illustrated in FIG. 4. Rotation of the hitch ball 19 from the functional configuration to the locked configuration is effected by lifting the t-bar 10 upwardly against the bias in the spring 11 to clear the extending end of the t-bar 10 from the bottom mount plate opening 13a and companion spring pin opening 22 in the pivot plate 15, to allow the pivot plate 15 to rotate on the pivot bolt 17, such that the curved front margin 27 clears the side plates 5 and the hitch ball 19 moves through the ball clearance opening 26, to the position illustrated in FIG. 4. As illustrated in FIG. 2, this movement also allows the ball mount nut 21 and the extending end of the ball mount bolt 20 to traverse the clearance groove 24 and facilitates relocation of the opposite spring pin opening 22 adjacent the t-bar 10, such that subsequent release of the t-bar 10 responsive to the bias in the spring 11, extends the end of the t-bar 10 through the relocated spring pin opening 22 and the fixed bottom mount plate opening 13a.
Referring again to FIGS. 3 and 4 of the drawing, it will be appreciated that the hitch ball 19 is conveniently stored rearwardly of the frame 1a, as illustrated in FIG. 4, to prevent injury resulting from stiking the hitch ball 19 when it is deployed as illustrated in FIG. 3. Furthermore, this deployment of the hitch ball 19 enhances the appearance of the trailer hitch 1.
In a most preferred embodiment of the invention, the frame 1a is constructed of steel and the rotatable pivot plate 15 is cut from steel plate stock having a thickness of about 3/8 inch. The pivot bolt 17 is typically about 1 inch in diameter and the side plates 5 are most preferably constructed of segments of 14-inch pipe.
Referring again to FIG. 1 of the drawing, the mount slots 3 facilitate adjustment of the bumper mount plate 2 on the bumper plate 31 and bumper 29 of substantially any truck 28, using a variety of spacings for the hitch mount bolts 30. Furthermore, since the pivot plate 15 is curved at the front margin 27 and around the sides and since the side plates 5 are also curved to accommodate the pivot plate 15, the pivot plate 15 cannot exit the frame 1a, even if the pivot bolt 17 and t-bar 10 should fail. This serves as an additional safety factor in the construction of the trailer hitch 1.
While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made and used therein and the appended claims are intended to cover all such modifications and combinations which may fall within the spirit and scope of the invention. | A trailer hitch having a rotatable draw plate, which trailer hitch is characterized by a metal frame adapted for mounting on the bumper plate of a truck bumper and a pivot plate rotatably attached to the frame for selectively positioning a removable hitch ball outwardly of the housing in functional configuration and inwardly of the housing in non-functional configuration. The pivot plate is secured with the hitch ball in selective functional and non-functional configuration by means of a latch located in the frame. In a preferred embodiment, the trailer hitch is bolted to the bumper plate of the truck and is located beneath the bumper plate and bumper. | 1 |
FIELD OF THE INVENTION
The present invention relates to methods for modifying the appearance of a substrate, and in particular methods that include depositing a coating on glass substrates to increase the visible light reflectance of the coated substrate while maintaining the reflected and transmitted color.
BACKGROUND
Glass substrates are used in a variety of applications such as automotive applications, architectural applications, aerospace applications, etc. For example, glass substrates are used as vision panels (i.e. front windshields, sidelights, etc.) in automotive applications. Depending on the end use of the glass substrate, the desired aesthetic properties such as, but not limited to, visible light reflectance, visible light transmittance, reflected color, etc., for the glass substrate will be different. In certain instances, it may be desirable to use a glass substrate that has a “brilliant appearance” as a vision panel in an automotive application. The term “brilliant appearance” means the glass substrate exhibits a visible light reflectance ranging from 5 to 20 percent, for example, from 9 to 15 percent, or from 10 to 12 percent. The use of such a vision panel could provide a competitive advantage to car manufactures.
The present invention provides a method for modifying the appearance of a glass substrate to give it a brilliant appearance. The method includes depositing a reflectance modifying coating on a particular side of a substrate.
SUMMARY OF THE INVENTION
In a non-limiting embodiment, the present invention is a method for modifying the appearance of a substrate comprising providing a substrate having first and second opposing surfaces and depositing a reflectance modifying coating on at least a portion of the first surface of the substrate, wherein the second surface has a visible light reflectance (R 1 ) ranging from 5 to 20 percent
In another non-limiting embodiment, the present invention is a method for modifying the appearance of a substrate comprising providing a substrate having first and second opposing surfaces and depositing a reflectance modifying coating by a CVD process on at least a portion of the first surface of a substrate, wherein the second surface has a visible light reflectance (R 1 ) ranging from 5 to 20 percent.
In yet another embodiment, the present invention is an article comprising a substrate having first and second opposing surfaces and a reflectance modifying coating on at least a portion of the first surface of the substrate, wherein the second surface has a visible light reflectance (R 1 ) ranging from 5 to 20 percent.
DESCRIPTION OF THE INVENTION
The present invention is a method for modifying the appearance of a substrate to provide a substrate having a brilliant appearance as defined above. The method of the present invention comprises depositing a reflectance modifying coating on at least a portion of a substrate. The reflectance modifying coating is deposited on the side of the substrate that is not the target of the modification. The side of the substrate opposite the reflectance modifying coating is the side (referred to herein as the “brilliant side”) with which the present invention is directed.
The reflectance modifying coating is non-absorbing of visible light and exhibits low dispersion. As used herein, “exhibits low dispersion” means the measured refractive index (n) of the coating at different wavelengths changes very little from 370 nanometers (nm) to 700 nm. The difference in refractive index measured at 370 nm and at 700 nm is referred to as Δn. In a non-limiting embodiment of the present invention, the reflectance modifying coating has a Δn of less than or equal to 0.35, for example, less than or equal to 0.30, or less than or equal 0.25. Table 1 lists Δn for various compounds.
TABLE 1
Δn for various materials
n at 370 nm
n at 700 nm
Δn
Ta 2 O 5
2.21
2.12
0.09
Al 2 O 3
1.66
1.61
0.05
TiO 2
2.52
2.22
0.30
SnO 2
2.07
1.96
0.11
In a non-limiting embodiment of the invention, the reflectance modifying coating has a refractive index ranging from 1.7 to 2.2 at 550 nm. Suitable materials for the reflectance modifying coating in this embodiment of the invention include, but are not limited to, alumina (Al 2 O 3 ), tin oxide (SnO 2 ), tantalum oxide (Ta 2 O 5 ), titania (TiO 2 ), zirconia (ZrO 2 ), zinc oxide (ZnO), zinc stannate (Zn X Sn 1−X O 2−X where x is greater than 0 but less than 1), or mixtures thereof.
According to the present invention, the step of depositing the reflectance modifying coating can be accomplished using conventional deposition techniques such as sol gel techniques, chemical vapor deposition (“CVD”), spray pyrolysis, vacuum deposition techniques and magnetron sputtered vacuum deposition (“MSVD”) as are well known in the art.
Suitable CVD methods of deposition are described in the following references, which are hereby incorporated by reference: U.S. Pat. Nos. 4,853,257; 4,971,843; 5,464,657; 5,599,387; and 5,948,131.
Suitable spray pyrolysis methods of deposition are described in the following references, which are hereby incorporated by reference: U.S. Pat. Nos. 4,719,126; 4,719,127; 4,111,150; and 3,660,061.
Suitable MSVD methods of deposition are described in the following references, which are hereby incorporated by reference: U.S. Pat. Nos. 4,379,040; 4,861,669; and 4,900,633.
Other well known deposition techniques such as plasma enhanced CVD (“PECVD”) and plasma assisted CVD (“PACVD”) can also be utilized in the present invention.
According to the present invention, the reflectance modifying coating can be deposited at any thickness. In one non-limiting embodiment, the physical thickness of the deposited reflectance modifying coating can range from equal to or less than 200 Å, for example, from 50 Å to 175 Å. The exact thickness of the deposited reflectance modifying coating depends on the performance properties desired in the final product.
According to the present invention, other steps can be performed in addition to depositing the reflectance modifying coating. In a non-limiting embodiment, the invention further comprises heating the substrate after the reflectance modifying coating has been deposited. Such heating step might be necessary if the coating is applied via a sol gel technique.
According to the present invention, the substrate is not limited to any particular category of materials. In a non-limiting embodiment of the invention, the substrate is a transparent material (i.e., exhibits a visible light transmittance of at least 10% at a thickness of 0.189 inches (4.8 mm) such as glass, plastic, etc. In another non-limiting embodiment of the invention, the substrate is made of glass commercially available from PPG Industries, Inc. (Pittsburgh, Pa.) under the names SOLEXTRA® glass, STARPHIRE® glass and VistaGray™ glass.
In yet another non-limiting embodiment of the invention, the substrate is a float glass ribbon as is well known in the art, and the glass is coated while it is on the molten tin. More specifically, the glass ribbon will be at a temperature ranging from 600° C. (1,100° F.) to 800° C. (1,472° F.) during the step of depositing a reflectance modifying coating. Because the glass ribbon is not dimensionally stable at temperatures above 800° C., it would not be practical to deposit a coating at a temperature that high.
After the steps of the present invention have been performed, a coated article will be realized that exhibits a visible light reflectance viewed from the uncoated side (R 1 ) ranging from 5 to 20 percent, for example, from 9 to 15 percent, or from 10 to 12 percent on its brilliant side.
In a non-limiting embodiment of the invention, after the method of the invention has been performed, a coated article having at least one side that has essentially the same color after the steps of the invention have been performed (i.e., E at time=1) as before the steps were performed (i.e., E at time=0). The variance in the color of a surface of an article before the steps of the invention have been performed and after the invention has been performed is quantified using ΔE (i.e., (E at time=1)−(E at time=0)). E is representative of the color of a surface as expressed in terms of color space coordinates a*, b* and L*. The lower the ΔE, the closer the color match.
According to the present invention, ΔE is the total color difference computed with a color difference equation which in this case is “CMC (1:c) color difference”. CMC (1:c) color difference is the color difference calculated by use of a formula developed by the Colour Measurement Committee of the Society of Dyers and Colourists of Great Britian. Since most of the substrates according to the invention can exhibit both reflected color and transmitted color, ΔE reflectance and ΔE transmittance can be measured and recorded for the substrates. Calculations for ΔE reflectance utilize reflected color space coordinates in the color difference equation. Calculations for ΔE transmittance utilize transmitted color space coordinates in the color difference equation.
In a non-limiting embodiment of the invention, an article undergoing the steps of the invention will have at least one surface (i.e., R 1 ) that exhibits a ΔE reflectance of less than or equal to 40, for example, less than or equal to 30, or less than or equal to 25. In another non-limiting embodiment of the invention, an article undergoing the steps of the invention will have at least one surface (i.e., R 1 ) that exhibits a ΔE transmittance of less than or equal to 15, for example, less than or equal to 10, or less than or equal to 8. In yet another non-limiting embodiment of the invention, an article undergoing the steps of the invention will have at least one surface that exhibits a visible light transmittance (Lta) of greater than 70 percent. In such an embodiment, the coated article can be made into a laminate, e.g. an automotive windshield.
The present invention also encompasses a coated article that includes a reflectance modifying coating.
EXAMPLES
The present invention is illustrated by the following non-limiting examples. Examples 1-9 were prepared in the following manner: for each example, the ingredients listed in Table 2 below were added to a jar in the order listed. After each ingredient was added to the jar, the jar was shaken to mix the contents.
TABLE 2
Ingredients used to make the Exemplary Compositions
Exs. 1–4
Ex. 5
Ex. 6
Ex. 7
Ex. 8
Ex. 9
Substrate
SOLEXTRA ®
SOLEXTRA ®
VistaGray ™ glass 2
VistaGray ™
STARPHIRE ®
STARPHIRE ®
glass 1
glass
glass
glass 3
glass
First Ingredient
95.06 g of 2-
6280.0 g of 1-
91.0 g of 1-
95.0 g of 1-
92.58 g of 2-
91.0 g of 1-
propanol
propanol
propanol
propanol
propanol
propanol
Second Ingredient
5.09 g of titanium
322.4 g of 1.5
7.14 g of
0.25 g of conc.
0.25 g of conc.
3.54 g of
IV butoxide
pentanediol
zirconium n-
HNO 3
HNO 3
zirconium n-
propoxide
propoxide
Third Ingredient
0.25 g of conc.
2.58 g of conc.
0.25 g of conc.
5.0 g of zirconium
2.58 g of titanium
0.25 g of conc.
HNO 3
HNO 3
HNO 3
n-propoxide
iso-butoxide
HNO 3
Fourth Ingredient
5.0 g of 1.5
220.7 g of
5.0 g of 1.5
5.0 g of 1.5
5.0 g of 1.5
5.0 g of 1.5
pentanediol
zirconium n-
pentanediol
pentanediol
pentanediol
pentanediol
propoxide
Fifth Ingredient
0.50 g of BYK ®-
2.54 g of BYK ®-
0.50 g of BYK ®-
0.50 g of BYK ®-
0.50 g of BYK ®-
0.50 g of BYK ®-
306 4
306
306
306
306
306
Sixth Ingredient
2.57 g of
32.3 g of
0.5 g of
0.48 g of
0.5 g of
tetramethyl-
tetramethyl-
tetramethyl-
tetramethyl-
tetramethyl-
ammonium
ammonium
ammonium
ammonium
ammonium
acetate
acetate
acetate
acetate
acetate
solution 20%
powder
powder
powder
powder
Seventh Ingredient
100.3 g of 1-
propanol
Eighth Ingredient
100.3 g of
zirconium n-
propoxide
Ninth Ingredient
100.8 g of 1-
propanol
Tenth Ingredient
100.8 g of
zirconium n-
propoxide
1 SOLEXTRA ® glass is a high performance green glass which is commercially available from PPG Industries, Inc. (Pittsburgh, PA).
2 VistaGray ™ glass is a gray glass which is commercially available from PPG Industries, Inc. (Pittsburgh, PA).
3 STARPHIRE ® glass is an ultra clear glass which is commercially available from PPG Industries, Inc. (Pittsburgh, PA).
4 BYK ®-306 is a highly effective silicone surface additive to provide good substrate wetting of critical substrates and good anti-crater performance by reduction of surface tension of the coatings. It is commercially available from BYK-Chemie GmbH (Germany).
The exemplary compositions were deposited on a 4 inch (10.16 cm)×4 inch (10.16 cm)×about 0.1522 inch (0.3866 cm) glass substrate using a spin coating method for Examples 1-4. The substrate thickness was about 0.139 inch (0.3531 cm) for Examples 6 and 7. The substrate thickness was about 0.4854 inch (1.2329 cm) for Examples 8 and 9. The thickness of the deposited coating is less than 100 angstroms. The substrate for each example is identified in Table 2. The spin coating method involved applying 5 ml of the exemplary composition at a spin speed of 600 rpm for a period of 30 seconds. The substrates were coated at room temperature (73.2° F.) in an environment at 17% relative humidity. For Example 5, the coating solution was applied to a 0.1516 inch (0.3851 cm) thick glass substrate by a draw-coating technique at a drawing speed of about 8 inches per minute. The coated glass samples were next heated for about 7 minutes at 600° C. in an electric muffle furnace.
Substrates coated with titania (Examples 1-4, and 8) were formed using precursor compositions that contained titanium IV butoxide or titanium iso-butoxide, and substrates coated with zirconia (Examples 5-7, and 9) were formed using compositions that contained zirconium n-propoxide. For Examples 2 and 4, the coating solution was further diluted from 5% TiO 2 to 2.5% TiO 2 prior to spin coating the substrate.
Exemplary substrates and controls (uncoated substrates) were analyzed for various transmittance and reflectance properties using a Perkin-Elmer Lambda 9 spectrophotometer. See the results of the analysis in Table 3. The performance properties were measured at normal incidence. Visible light transmittance (Lta) and visible light reflectance on the brilliant side (R 1 ) were measured using C.I.E. 1931 standard illuminant “A” over the wavelength range 380 to 770 nanometers at 10 nanometer intervals. Color (L*, a*, b*) was measured using illuminant “D65” with a 10° observer.
TABLE 3
Performance Properties of Substrates according to the Present Invention
Uncoated
SOLEXTRA ®
Glass
Ex. 1
Ex. 2
Ex. 3
Ex. 4
Ex. 5
Transmittance
Properties
Lta
72.86
60.88
68.97
59.74
68.63
68.83
L*
89.88
83.27
87.74
82.62
87.55
87.71
a*
−8.35
−7.63
−8.26
−7.49
−8.24
−7.96
b*
−5.08
−0.04
−2.53
0.14
−2.37
−3.30
ΔE CMC (1:1)
7.08
3.06
7.53
3.27
2.32
Reflectance
Properties
R1
6.93
16.49
10.11
17.47
10.47
10.46
L*
32.24
49.86
39.54
51.13
40.24
40.02
a*
−2.94
−7.11
−3.97
−7.58
−4.10
−4.70
b*
−2.53
−13.55
−10.31
−13.44
−10.73
−8.19
ΔE CMC (1:1)
24.94
12.59
26.26
13.53
11.21
Uncoated
Uncoated
VistaGray ™
STARPHIRE ®
glass
Ex. 6
Ex. 7
glass
Ex. 8
Ex. 9
Transmittance
Properties
Lta
73.31
68.12
70.79
90.72
86.17
88.84
L*
88.84
86.14
87.54
96.36
94.24
95.51
a*
−2.97
−2.75
−2.93
−0.59
−0.52
−0.54
b*
1.44
3.14
2.47
0.08
2.55
1.05
ΔE CMC (1:1)
2.62
1.58
3.93
1.35
Reflectance
Properties
R1
6.95
10.93
8.92
7.90
12.31
9.78
L*
32.32
40.14
36.35
33.84
42.51
37.84
a*
−2.98
−2.52
−1.79
−0.16
−0.49
−0.45
b*
−2.77
−4.22
−3.39
−0.45
−8.00
−3.76
ΔE CMC (1:1)
12.19
7.61
15.09
6.78
CONCLUSION
The performance results show that in non-limiting Examples 1-9, glass substrates coated according to the present invention (i.e., the reflectance modifying coating has a Δn as specified) having a visible light reflectance (R 1 ) on their brilliant sides ranging from 10 to 18 percent can be realized according to the present invention. Also, the reflectance modification can be achieved without changing the reflected color of the substrate as exhibited by the ΔE reflectance values ranging from 7 to 25. The reflectance modification can be achieved without changing the transmitted color of the substrate as exhibited by the ΔE transmittance values ranging from 1 to 8. Further, the method of the present invention can be performed on various substrates as illustrated by Examples 1-4 and 5 (SOLEXTRA® glass); Examples 6 and 7 (VistaGray™ glass); and Examples 8 and 9 (STARPHIRE® glass).
It will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed in the foregoing description. Such modifications are to be considered as included within the scope of the invention. Accordingly, the particular embodiments described in detail hereinabove are illustrative only and are not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof. | A method for modifying the appearance of a substrate is disclosed. The method includes providing a substrate having first and second opposing surfaces and depositing a reflectance modifying coating on at least a portion of the first surface of the substrate, wherein the second surface has a visible light reflectance (R 1 ) ranging from 5 to 20 percent. | 2 |
RELATED APPLICATIONS
[0001] This application is related to U.S. patent application Ser. No. 10/313,491, (Attorney Docket No. TI-34486), filed on Dec. 5, 2002, entitled “METHODS FOR FORMING SINGLE DAMASCENE VIA OR TRENCH CAVITIES AND FOR FORMING DUAL DAMASCENE VIA CAVITIES”, the entirety of which is hereby fully incorporated by reference.
FIELD OF INVENTION
[0002] The present invention relates generally to semiconductor processing and more particularly to implementing in-situ ashing in association with damascene processing in forming interconnect structures in the fabrication of semiconductor devices.
BACKGROUND OF THE INVENTION
[0003] In the manufacture of semiconductor products such as integrated circuits, individual electrical devices are formed on or in a semiconductor substrate, and are thereafter interconnected to form electrical circuits. Interconnection of these devices is typically accomplished by forming a multi-level interconnect network structure in layers formed over the electrical devices, by which active elements of the devices are connected to one another to create the desired circuits. Individual wiring layers within the multi-level network are formed by depositing an insulating or dielectric layer over the discrete devices or over a previous interconnect layer, and patterning and etching contact holes or openings such as vias. Conductive material, such as tungsten is then deposited into the vias to form inter-layer contacts. A conductive layer may then be formed over the dielectric layer and patterned to form wiring interconnections between the device vias, thereby creating a first level of basic circuitry. Dielectric material is then deposited over the patterned conductive layer, and the process may be repeated any number of times using additional wiring levels laid out over additional dielectric layers with conductive vias therebetween to form the multi-level interconnect network.
[0004] As device densities and operational speeds continue to increase, reduction of the delay times in integrated circuits is desired. These delays are related to the resistance of interconnect metal lines through the multi-layer interconnect networks as well as to the capacitance between adjacent metal lines. In order to reduce the resistivity of the interconnect metal lines formed in metal layers or structures, recent interconnect processes have employed copper instead of aluminum. However, difficulties have been encountered in patterning (etching) deposited copper to form wiring patterns. Furthermore, copper diffuses rapidly in certain types of insulation layers, such as silicon dioxide, leading to insulation degradation and/or copper diffusion through the insulation layers and into device regions.
[0005] Copper patterning difficulties have been avoided or mitigated through the use of single and dual damascene interconnect processes in which cavities are formed (etched) in a dielectric layer. Copper is then deposited into the trenches and over the insulative layer, followed by planarization using a chemical mechanical polishing (CMP) process to leave a copper wiring pattern including the desired interconnect metal lines inlaid within the dielectric layer trenches. In a single damascene process copper trench patterns or vias are created which connect to existing interconnect structures thereunder, whereas in a dual damascene process, both vias and the trenches are filled at the same time using a single copper deposition and a single CMP planarization.
[0006] Copper diffusion issues have been addressed using copper diffusion barriers formed between the copper and the dielectric layers as well as between the copper and the silicon substrate. Such barriers are typically formed using conductive compounds of transition metals such as tantalum nitride, titanium nitride, and tungsten nitride as well as the various transition metals themselves. Insulators such as silicon nitride and silicon oxynitride have also been used as barrier materials between copper metallurgy and insulative layers. More recently, silicon carbide (SiC) has been used as a copper diffusion barrier material, as well as in etch-stop layers employed during trench and/or via cavity formation.
[0007] RC delay times have also been reduced by recent developments in low dielectric constant (low-k) dielectric materials formed between the wiring metal lines, in order to reduce the capacitance therebetween and consequently to increase circuit speed. Examples of low-k dielectric materials include spin-on-glasses (SOGs), as well as organic and quasi-organic materials such as polysilsesquioxanes, fluorinated silica glasses (FSGs) and fluorinated polyarylene ethers. Totally organic, non silicaceous materials such as fluorinated polyarylene ethers, are seeing an increased usage in semiconductor processing technology because of their favorable dielectric characteristics and ease of application. Other low-k insulator materials include organo-silicate-glasses (OSGs), for example, having dielectric constant (k) as low as about 2.6-2.8, and ultra low-k dielectrics having dielectric constant below 2.5. OSG materials are low density silicate glasses to which alkyl groups have been added to achieve a low-k dielectric characteristic.
[0008] Conventional single and dual damascene interconnect processing typically includes the formation of via cavities through a dielectric layer, in which the via etch process stops on an etch-stop layer underlying the dielectric. A resist ashing process is then employed to remove a via etch photoresist mask, and an optional wet clean operation is then performed to remove polymers and other residual materials from the via cavity. In the single damascene case, an etch-stop layer etch process is then performed to expose the underlying structure, such as a conductive feature (e.g., copper feature) in a pre-existing interconnect layer. The via cavity is then filled with copper and the wafer is planarized, after which further interconnect levels may then be fabricated. In the dual damascene case, after the via ashing and wet clean operations, a trench cavity is patterned and etched, followed by another ashing operation and optionally another wet clean. Thereafter an etch-stop layer etch is performed to expose the underlying structure, and the via and trench cavities are simultaneously filled with copper and the wafer is planarized.
[0009] In the conventional single and dual damascene interconnect processes, however, the etch-stop layer etch process not only etches the etch-stop layer, but also recesses the exposed dielectric material. As a result, the inter level or inter layer dielectric (ILD) and/or intra-metal dielectric (IMD) becomes thinner. In addition, in the single damascene case, the etch-stop layer etch and subsequent cleaning steps (e.g., ashing and wet clean) often change the via profile and increase the critical dimensions (CDs) thereof. As new technologies demand ever smaller CDs in semiconductor devices, CD control becomes more important. Furthermore, the conventional via sidewalls become bowed during the etch-stop etch and intervening cleaning after the via etch process, leading to via profile distortion. In the dual damascene case, the etch-stop etch and subsequent cleaning also affect the top dielectric surface and sidewalls of the trench cavity. Consequently, the effective dielectric constant of the resulting structure can be increased. Thus, there remains a need for improved methods for fabricating single and/or dual damascene interconnect structures in semiconductor wafers by which these and other adverse effects can be mitigated or overcome, while concurrently streamlining the fabrication process to become more efficient in terms of cycle times, cost effectiveness, etc.
SUMMARY OF THE INVENTION
[0010] The following presents a simplified summary in order to provide a basic understanding of one or more aspects of the invention. This summary is not an extensive overview of the invention, and is neither intended to identify key or critical elements of the invention, nor to delineate the scope thereof. Rather, the primary purpose of the summary is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
[0011] One or more aspects of the present invention relate to forming single or dual damascene interconnect structures in the fabrication of semiconductor devices in manners that mitigate the above mentioned and other adverse effects. One or more aspects of the invention may be employed, for example, to facilitate better via critical dimension (CD) control, improve selectivity of etch-stop layer to inter layer dielectric (ILD) and/or intra-metal dielectric (IMD) material, and/or to simplify and make the flow of the fabrication process more efficient and/or cost effective.
[0012] In accordance with one or more aspects of the present invention, a method of performing an ashing act in an interconnect structure formation process that is integral with forming one or more semiconductor devices is disclosed. The method includes forming a via for the interconnect structure including etching via ILD layer and etch-stop layer in-situ, and then performing an in-situ ashing in forming the via.
[0013] To the accomplishment of the foregoing and related ends, the following description and annexed drawings set forth in detail certain illustrative aspects and implementations of the invention. These are indicative of but a few of the various ways in which the principles of the invention may be employed. Other aspects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIGS. 1A-1F are partial side elevation views in section illustrating a conventional single damascene via formation flow.
[0015] FIGS. 2A-2F are partial side elevation views in section illustrating a conventional via-first dual damascene formation flow.
[0016] FIG. 3 is a flow diagram illustrating an exemplary method of forming a single damascene interconnect structure in accordance with one or more aspects of the present invention.
[0017] FIGS. 4A-4P are partial side elevation views in section illustrating fabrication of an exemplary single damascene via or trench in accordance with one or more aspects of the present invention.
[0018] FIG. 5A is a cross-sectional side elevation view scanning electron microscope (SEM) image of single damascene vias formed according to conventional processes following ex-situ etch-stop etching.
[0019] FIG. 5B is a cross-sectional side elevation view SEM image of single damascene vias formed according to related application (Ser. No. 10/313,491) following in-situ etch-stop etching and conventional ex-situ ashing and utilizing the same ILD film stack as that used as in FIG. 5A .
[0020] FIG. 5C is a cross-sectional side elevation view SEM image of single damascene vias formed according to related application (Ser. No. 10/313,491) following in-situ etch-stop etching, conventional ex-situ ashing and wet solvent clean.
[0021] FIG. 5D is a cross-sectional side elevation view SEM image of single damascene vias formed according to one or more aspects of the present invention following in-situ etch-stop etching, in-situ ashing and wet solvent clean and utilizing the same ILD film stack as that used as in FIG. 5C .
[0022] FIG. 5E is a top view SEM image of single damascene vias formed according to related application (Ser. No. 10/313,491) following in-situ etch-stop etching and conventional ex-situ ashing.
[0023] FIGS. 5F and 5G are top view SEM images of single damascene vias formed according to one or more aspects of the present invention following in-situ etch-stop etching and in-situ ashing.
[0024] FIGS. 6A and 6B provide a flow diagram illustrating an exemplary method of forming a dual damascene interconnect structure in accordance with one or more aspects of the present invention.
[0025] FIGS. 7A-7N are partial side elevation views in section illustrating fabrication of an exemplary via-first dual damascene interconnect structure in accordance with one or more aspects of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The present invention will now be described with reference to the attached drawings, wherein like reference numerals are used to refer to like elements throughout, and wherein the various structures are not necessarily drawn to scale. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects of the present invention. It may be evident, however, that one or more aspects of the present invention may be practiced with a lesser degree of these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more aspects of the present invention.
[0027] One or more aspects of the present invention relate to forming single and/or dual damascene interconnect structures, including via and/or trench cavities or openings during interconnect processing of integrated circuits and other semiconductor devices. One or more implementations of the invention are hereinafter illustrated and described in the context of single or dual damascene trench and/or via cavity formation in low-k organo-silicate-glass (OSG) structures, where silicon carbide (SiC) etch-stop layers are employed. However, it will be appreciated by those skilled in the art that the invention is not limited to the exemplary implementations illustrated and described hereinafter. In particular, the various aspects of the invention may be employed in association with processing of devices using OSG, fluorinated silica glasses (FSG), or other low-k or ultra low-k dielectric materials, and other types of etch-stop layer materials. Further, the dual damascene formation methods of the invention may be employed in association with via-first and/or trench-first implementations.
[0028] Referring initially to FIGS. 1A-1F , one or more problems or shortcomings of conventional single damascene interconnect processing are illustrated and described to provide an appreciation of the benefits possible with the invention. FIG. 1A illustrates a wafer 2 comprising a silicon substrate 4 , in which a conductive silicide structure 5 is formed. An initial contact layer is formed over the substrate 4 , including a dielectric 6 with a tungsten contact 7 extending therethrough. A first interconnect structure is formed over the contact layer, including an etch-stop layer (not shown), over which a dielectric 8 is deposited. A conductive feature 10 is formed through the dielectric 8 and the etch-stop layer to provide electric coupling to the contact 7 . To form a single damascene interconnect level, a SiN or SiC etch-stop layer 12 is formed over the dielectric 8 and the conductive feature 10 , and a dielectric layer 14 is formed over the etch-stop layer 12 to a thickness 14 ′ of about 5000-6000 Å. A bottom anti-reflective coating (BARC) layer 16 is deposited over the dielectric 14 and a resist mask 18 is formed over the BARC layer 16 . In FIG. 1A , a via etch process 22 is performed to form an aperture or via cavity 24 in the BARC and dielectric layers 16 and 14 , respectively, which is stopped on the etch-stop material 12 .
[0029] Thereafter in FIG. 1B , a resist ashing process 26 is used to remove the mask 18 and BARC 16 , and a wet clean operation 28 is performed in FIG. 1C . The resulting via cavity 24 has a critical dimension (CD) 20 . In FIG. 1D , an etch-stop etch process 30 is performed to etch the exposed etch-stop layer material 12 at the bottom of the via cavity 24 , which also removes dielectric material from the exposed top of the layer 14 , as well as from the sidewalls of the cavity 24 . Thereafter in FIG. 1E , another ashing operation 32 is performed and a wet clean 34 is performed in FIG. 1F . Following this conventional single damascene process, the resulting via cavity 24 has a critical dimension 20 ′ ( FIG. 1F ), which may be significantly larger than the original dimension 20 ( FIG. 1C ). In addition, the etch-stop etch and cleaning processes 30 , 32 , and 34 have reduced the dielectric (e.g., ILD) thickness of the layer 14 to a smaller dimension 14 ″ ( FIG. 1F ), which may be significantly less than the starting dimension 14 ′ ( FIG. 1A ). For low-k dielectrics, the etch-stop etch and cleaning processes 30 , 32 and 34 can also affect low-k film properties of top surface and sidewalls, thus increasing the effective dielectric constant. Further, the ashing acts 26 and 32 are performed ex-situ, or rather in fabrication components that are separate from the chamber or chambers wherein the other acts (e.g., deposition, etching, etc.) are performed. Such ex-situ ashing adds complexity to the process flow and increases cycle times and equipment costs, among other things, as wafers have to be moved back and forth between processing tools. Ex-situ ashing may also, at times, fail to adequately remove etch residues.
[0030] Referring now to FIGS. 2A-2F , similar problems are seen in conventional dual damascene processing. FIG. 2A illustrates a wafer 52 comprising a substrate 54 , in which a conductive silicide structure 55 is formed. An initial contact layer is formed over the substrate 54 , including a dielectric 56 and a conductive contact 57 . A first interconnect structure is formed over the contact layer, including an etch-stop layer (not shown), and a dielectric 58 in which a conductive feature 60 is formed to provide electric coupling to the contact 57 . An etch-stop layer 62 is formed over the dielectric 58 and over the contact 60 , and a dielectric layer 64 is formed over the etch-stop layer 62 to a thickness of about 7000-8000 Å. A BARC layer 66 is then formed over the dielectric 64 and a resist mask 68 is formed over the BARC layer 66 . A via etch process 72 is performed in FIG. 2A to form a hole or via cavity 74 in the layers 66 and 64 , stopping on the etch-stop layer 62 . In FIG. 2B , a resist ashing process 76 and a wet clean 78 are performed to remove the mask 68 and the BARC 66 , resulting in via cavity 74 having a critical dimension of 70 .
[0031] In FIG. 2C , a second BARC layer 80 and a trench resist mask 82 are formed over the wafer 52 , and a trench etch operation 84 is performed to form a trench cavity or opening 86 leaving a CD of 71 , and leaving a trench bottom surface thickness 88 of about 3000-4000 Å above the previous interconnect dielectric material 58 . Another ashing operation 90 and wet clean 92 are performed in FIG. 2D , and an etch-stop etch process 94 is then performed in FIG. 2E to etch the exposed etch-stop layer material 62 at the bottom of the via cavity 74 . As illustrated in FIG. 2E , the etch-stop etch 94 also removes dielectric material from the exposed top of the layer 64 , from the bottom and sidewalls of the trench cavity 86 , and also from the sidewalls of the via cavity 74 . Thereafter in FIG. 2F , another ashing operation 96 and a wet clean 98 are performed. Thus the dielectric layer 64 has a reduced trench bottom surface thickness 88 ′ from it's original thickness 88 ( FIG. 2C ), and CDs have been increased to 70 ′ and 71 ′ for the via 74 and the trench 86 from their original dimensions 70 and 71 ( FIG. 2C ).
[0032] In the conventional single and dual damascene processes illustrated in FIGS. 1A-1F and 2 A- 2 F, respectively, it is thus seen that the etch-stop layer etch steps in FIGS. 1D and 2E adversely affect the profiles and CDs of the interconnect cavities and structures, leading to thinning of the ILD/IMD layers and corresponding increase in the effective dielectric constant of the finished structures. In order to reduce the capacitance between interconnect routing lines and vias and consequently to increase circuit speed in modern semiconductor devices, the present invention provides methods for single and dual damascene interconnect structure formation by which these difficulties can be mitigated or avoided, while the number of acts in these processes are also reduced, thus streamlining the processes and making them more efficient and cost effective, among other things.
[0033] Referring now to FIG. 3 , an exemplary method 100 is illustrated and described hereinafter for forming a single damascene interconnect structure, such as a via or a trench. Although the method 100 and other methods herein are illustrated and described below as a series of acts or events, it will be appreciated that the present invention is not limited by the illustrated ordering of such acts or events. For example, some acts may occur in different orders and/or concurrently with other acts or events apart from those illustrated and/or described herein, in accordance with the invention. In addition, not all illustrated steps may be required to implement a methodology in accordance with the present invention. Furthermore, the methods according to the present invention may be implemented in association with the formation and/or processing of structures illustrated and described herein as well as in association with other structures not illustrated.
[0034] The exemplary method 100 is described hereinafter in the context of a single damascene via formation in a semiconductor wafer. However, it will be appreciated that the exemplary method 100 , and other single damascene methodologies of the present invention, may be employed alternatively or in combination in forming a single damascene trench structure. Beginning at 102 , the method 100 comprises forming an etch-stop layer over an existing interconnect structure at 104 (e.g., over a previous damascene structure or over an initial contact level), and forming a low-k dielectric layer over the etch-stop material at 106 . Any appropriate etch-stop and dielectric materials and layer fabrication techniques may be employed at 104 and 106 , respectively, such as depositing SiN or SiC etch-stop material to a thickness of about 600 Å using any appropriate deposition technique such as chemical-vapor deposition (CVD) or the like. A hardmask or cap layer can be optionally used. A BARC (bottom anti-reflective coating) layer is optionally deposited at 108 of any appropriate organic material having anti-reflective properties to a thickness of about 800 Å over the dielectric layer. A resist mask is then deposited and patterned at 110 , having an opening in a prospective via region of the wafer, for example, using known photolithographic techniques and photoresist materials.
[0035] The dielectric layer may be formed at 106 via any appropriate technique, for example, by deposition of organo-silicate-glass (OSG) material to a thickness of about 5000 Å over the SiC etch-stop layer. Any appropriate deposition process may be employed in forming the OSG layer at 106 . In operation, the low-k dielectric layer provides insulation between overlying and underlying conductive features, such as between a conductive feature in an existing interconnect structure and later-formed features above or in trenches in the low-k dielectric. In this regard, it is noted that OSG material provides relatively low dielectric constant characteristics desirable in avoiding or mitigating RC delays and cross-talk between signals in the finished semiconductor device. In addition, it will be appreciated that any dielectric materials may be used in forming the dielectric layer at 106 , including but not limited to OSG, FSG, ultra low-k dielectrics, or the like, wherein the invention is not limited to use in association with the OSG materials discussed herein.
[0036] Thereafter, an in-situ process flow 112 is performed wherein a via cavity is formed through the BARC, dielectric, and etch-stop layers, which may be performed in a single reactive ion etch (RIE) tool, for example, without breaking vacuum. At 114 a , the exposed BARC layer is etched, using the patterned resist as a mask, and a via main etch is performed at 114 b to remove a portion of the dielectric layer, creating a via cavity or opening therein. Thereafter, a via over-etch process is performed at 114 c to remove the remaining portion of the dielectric material in the cavity and to expose a portion of the underlying etch-stop layer material. At 116 , the exposed portion of the etch-stop material is etched to extend the cavity and to expose a conductive feature in the underlying interconnect structure, with substantially no intervening processing between the via etch acts of 114 a - 114 c and the etch-stop etch of 116 .
[0037] In the exemplary method 100 , the via etch at 114 a - 114 c and the etch-stop etch at 116 are performed in-situ within a single reactive ion etching (RIE) tool. However, other implementations are possible within the scope of the invention, wherein the etch-stop etch at 116 is performed concurrently with the via etch 114 or immediately thereafter. In addition, the invention also contemplates alternative implementations in which the via and etch-stop etch acts are performed with substantially no processing steps therebetween. For example, no ashing or wet etch operations are performed between the via etch 114 and the etch-stop layer etch at 116 in the illustrated method 100 . Thus, compared with the conventional single damascene methods (e.g., FIGS. 1A-1F above), the exemplary method 100 streamlines the process by removing an intermediate act (e.g., ashing 26 in FIG. 1B ). Additionally, performing the etch-stop etch with the patterned resist mask in place mitigates damage to the via cavity (e.g., 20 vs 20 ′, FIGS. 1C and 1F ) as the mask affords some protection to the dielectric layer.
[0038] It is further noted that while the exemplary method 100 provides in-situ etching of the via cavity through the dielectric layer (e.g., 114 ) and etch-stop etching to extend the via cavity through the etch-stop layer, that other implementations are possible within the scope of the present invention where these or equivalent acts are performed in different etch tools. Moreover, one or more process steps or acts may be performed between the via and etch-stop etch acts in accordance with the invention where the dielectric layer is covered with the resist mask during the etch-stop etch. In the illustrated method 100 , the resist mask from the via etch steps remains during the etch-stop etch 116 . However, other implementations are possible within the scope of the invention, wherein all or a portion of the dielectric is covered by any means during the entirety of, or during a portion of, the etch-stop etch 116 . Also, while the exemplary method 100 provides a multi-step etch (e.g., 114 b , 114 c ) through the dielectric layer, other implementations are contemplated, wherein the BARC etch, the via etch, and/or the etch-stop etch acts may individually comprise single step and/or multi-step operations, within the scope of the present invention.
[0039] In the illustrated example, the acts 114 a - 114 c and 116 are performed in a single RIE etch tool, with appropriate etch chemistries being changed accordingly, in order to remove material from the layer currently exposed in the prospective via region (e.g., the BARC layer, then the dielectric layer, then the etch-stop layer). Furthermore, while illustrated and described with respect to organic BARC materials, OSG type low-k dielectric material, and SiC or SiN etch-stop layer materials, any appropriate materials may be employed in forming these layers in accordance with the invention, where appropriate etch chemistries and selectivities may be selected in performing the etch operations 114 - 116 to form and extend the via cavity. Furthermore, although illustrated in the context of a single damascene via formation flow, the invention contemplates implementations for forming single damascene trench structures and cavities, wherein the above described etch techniques may be employed to form a trench opening or cavity through the BARC, dielectric, and etch-stop layers.
[0040] In one exemplary implementation of the method 100 , the via etch through the dielectric layer at 114 b and 114 c comprises a two-step process having different etch chemistries for each such step. The main etch at 114 b is performed to etch the majority of the dielectric material in the cavity, and leaves about 1000-2000 Å of dielectric material remaining. The process parameters are then switched to the over-etch at 114 c , which is time controlled to stop on the etch-stop layer, although other forms of process control may be employed to stop on the etch-stop material, wherein the exemplary over-etch at 114 c has a higher selectivity to the etch-stop layer than does the main etch at 114 b.
[0041] Once the etch-stop layer has been exposed, the etch process parameters are again adjusted for etching the etch-stop material with a selectivity to the underlying (e.g., pre-existing) interconnect structure, so as to expose an underlying conductive feature (e.g., copper structure). It is noted that the method 100 provides a resist mask over the dielectric layer while etching the exposed portion of the etch-stop layer at 116 , since there is no intervening ashing or wet etch process to remove the via resist mask. This, in turn, advantageously mitigates or avoids etch-stop etch related damage to the dielectric material during the etch-stop etch at 116 , by which the via CD and profile, and the dielectric layer thickness are protected.
[0042] Following the in-situ process at 112 , the method 100 proceeds to 118 , where a resist stripping or ashing operation is performed to remove the resist mask initially formed at 110 , as well as the BARC material deposited at 108 . However, unlike conventional ashing operations (e.g., 32 , FIG. 1E ) which are performed ex-situ, ashing operation 118 is performed in the same processing chamber as the via etch 114 a - 114 c and etch-stop etch 116 , or in a different chamber on the same etcher. In the latter situation, the wafers would likely be transferred under vacuum. Performing the ashing operation 118 in-situ according to one or more aspects of the present invention, allows the process to be further streamlined as wafers do not have to be transferred between different processing tools. In-situ acts 114 a , 114 b , 114 c , 116 and 118 are thus referenced as 112 ′ in the exemplary flow 100 .
[0043] Such an in-situ ash 118 may also be performed with an RIE plasma asher that can remove tough residues more effectively as compared to ex-situ plasma ashers using downstream plasmas. The in-situ ash is also performed at a relatively low power and low pressure as compared to conventional systems. For example, the ash ing operation 118 may be performed at a power of about 150 to 400 W and a pressure of about 20 to 80 mT. Further, the operation 118 may be performed for a time of about 15 to 60 seconds with an oxygen (O 2 ) flow of about 100 to 500 sccm and at a chuck temperature of about 20 to 40 degrees Celsius. Additionally, other ash chemistries such as H 2 /Ar, H 2 /He, H 2 /N 2 O 2 /H 2 , O 2 /N 2 can also be used. The in-situ ash thus allows the operation to be more effective and to be performed more efficiently and cost effectively as fewer actions have to be taken, less equipment is needed, and cycle time is thereby reduced.
[0044] A wet clean operation is then optionally performed at 120 , such as using a wet solvent to remove any residue from the RIE etch acts which may still remain after the ashing operation at 118 . A copper diffusion barrier layer is then formed at 122 , which serves to line the via cavity, examples of which include conductive compounds of transition metals such as tantalum nitride, titanium nitride, and tungsten nitride as well as the various transition metals themselves. A seed copper layer is then deposited over the diffusion barrier at 124 , to facilitate subsequent copper filling of the via cavity.
[0045] An electro-chemical deposition (ECD) process is then performed at 126 to deposit a copper layer over the wafer, which fills the via cavity, and overlies the barrier layer on top of the remaining dielectric. Any appropriate copper deposition process or acts 124 - 126 may be employed, which may be a single step or a multi-step process. Thereafter at 128 , a chemical mechanical polishing (CMP) process is performed to planarize the upper surface of the device, which ideally stops on the dielectric layer and reduces the diffusion barrier and the deposited copper. In this manner, the planarization process 128 electrically separates the conductive (e.g., copper) via from other such vias formed in the device, whereby controlled connection of the underlying conductive feature with subsequently formed interconnect structures can be achieved, after which the method 100 ends at 130 .
[0046] Referring also to FIGS. 4A-4P , an exemplary wafer 202 is illustrated undergoing single damascene interconnect structure formation processing in accordance with this aspect of the invention. FIGS. 4A-4P illustrate formation of a single damascene via structure. However, the invention may also be employed in formation of a single damascene trench structure (not shown) according to the principles illustrated and described herein. FIG. 4A illustrates the wafer 202 at an intermediate stage of fabrication, comprising a silicon substrate 204 , in which a conductive silicide structure 205 is formed. An initial contact layer is formed over the substrate 204 , comprising a dielectric 206 with a tungsten contact 207 , for example, extending therethrough, and electrically contacting the silicide 205 . A previously formed interconnect structure is formed over the contact layer, comprising an etch-stop layer (not shown) and a dielectric 208 in which a conductive feature (e.g., copper trench metal) 210 is formed to provide electric coupling to the contact 207 . The invention may be employed in association with any existing interconnect structure to provide electrical coupling to a conductive feature therein. In FIG. 4B , a SiN or SiC etch-stop layer 212 is formed over the dielectric 208 and the conductive feature 210 of the existing interconnect structure to a thickness 212 ′ of about 500-800 Å via a deposition process 213 . A dielectric layer 214 , such as a low-k OSG dielectric material or the like, is formed via a deposition process 215 in FIG. 4C over the etch-stop layer 212 to a thickness 214 ′ of about 5000-6000 Å.
[0047] An organic BARC layer 216 is deposited in FIG. 4D over the dielectric 214 via a deposition process 217 to a thickness 216 ′ of about 600-800 Å. Thereafter in FIG. 4E , a resist mask 218 is formed over the BARC layer 216 having an opening 220 in a prospective via region. In FIG. 4F , a via BARC etch process 222 is performed to remove material from the BARC layer 216 in the via region 220 . A via main etch process 224 is then employed in FIG. 4G to form a via cavity 226 in the dielectric layer 214 , leaving a thickness 228 of dielectric material 214 unetched at the bottom of the via cavity 226 , wherein the via main etch 224 has a substantial etch rate and is substantially anisotropic. A via over-etch process 230 (e.g., which is highly selective with respect to the etch-stop layer 212 ) is then performed in FIG. 4H to further form the cavity 226 through the rest of the dielectric layer 214 , stopping on and exposing a portion of the underlying etch-stop layer 212 . At this point the via 226 has a width or critical dimension (CD) of 231 . An etch-stop etch 232 is performed immediately thereafter (e.g., concurrently with the over-etch 230 ) in FIG. 4I .
[0048] Thereafter in FIG. 4J , a resist ashing process 234 is used to remove the remaining resist mask 218 and the BARC layer 216 , and a wet clean operation 236 is performed in FIG. 4K . It is noted in FIG. 4K , that unlike the conventional single damascene process (e.g., FIG. 1F above), the profile and CD 231 of the via cavity 226 remains essentially the same as prior to the etch-stop etch 232 , since the resist mask 218 was maintained during the etch-stop etch 232 ( FIG. 4I ). In this regard, having the resist 218 over the dielectric 214 helps preserve the CD and profile of the via 226 . Additionally, unlike conventional ashing operations which are performed on separate fabrication tools and that require wafers to be moved back and forth between different tools, ashing operation 234 is performed in the same processing chamber as the etch-stop etch 232 , or in a different chamber on the same etcher. In the latter situation, the wafers would likely be transferred under vacuum. Performing the ashing operation 234 in-situ in accordance with one or more aspects of the present invention, allows the process to be streamlined as wafers do not have to be transferred between different processing tools.
[0049] An in-situ ash also allows a RIE plasma to be utilized at 234 . A RIE plasma ash process can remove tough residues more effectively as compared to ex-situ plasma ash using downstream plasmas. The in-situ ash is also performed at a relatively low power and low pressure as compared to conventional systems. For example, the ashing operation 234 may be performed at a power of about 150 to 400 W and a pressure of about 20 to 80 mT. Further, the operation 234 may be performed for a time of about 15 to 60 seconds with an oxygen (O 2 ) flow of about 100 to 500 sccm and at a chuck temperature of about 20 to 40 degrees Celsius. Additionally, other ash chemistries such as H 2 /Ar, H 2 /He, H 2 /N 2 O 2 /H 2 , O 2 /N 2 can also be used. The in-situ ash thus allows the operation to be more effective and to be performed more efficiently and cost effectively as fewer actions have to be taken, less equipment is needed, and cycle time is thereby reduced.
[0050] In FIG. 4L , a copper diffusion barrier layer 238 is formed via a deposition process 237 , and a copper seed layer 240 is formed in FIG. 4M via a deposition process 239 . An ECD, for example, copper deposition process 241 is then performed in FIG. 4N to deposit copper 242 , thereby filling the via cavity 226 and overlying the remainder of the wafer 202 , after which a CMP planarization process 243 is employed in FIG. 4O to planarize the wafer 202 , thus completing the conductive single damascene via structure.
[0051] Thereafter, as illustrated in FIG. 4P , a subsequent interconnect level or layer may be constructed, for example, using the above-described single damascene techniques, comprising another etch-stop layer 244 , a low-k dielectric layer 245 , and a trench structure comprising a copper diffusion barrier layer 246 , a copper seed layer 247 , and ECD deposited copper fill material 248 . Any number of such layers or levels may be fabricated in accordance with the present invention, to provide electrical coupling to the conductive feature 210 in the existing interconnect structure of the wafer 202 .
[0052] Referring also to FIGS. 5A and 5B , scanning-electron microscope (SEM) images are provided to illustrate some of the advantages which may be realized in practicing the single damascene methods of the invention, including the exemplary method 100 above, as contrasted with conventional techniques. FIG. 5A provides a cross-sectional SEM image 250 of single damascene vias after etch-stop etching, formed according to conventional processes (e.g., FIGS. 1A-1F above). FIG. 5B is a cross-sectional SEM image 262 (at the same scale and utilizing the same ILD film stack as the image 250 of FIG. 5A ) of single damascene vias formed according to the present invention (e.g., FIGS. 3 and 4 A- 4 P) with in-situ etch-stop etching and ashing.
[0053] As can be seen from FIGS. 5A and 5B , the conventional single damascene technique ( FIG. 5A ) provides significant reduction in the dielectric thickness 251 (e.g., due to the exposure of the dielectric material during the etch-stop etch or a poor selectivity to the top dielectric), whereas the thickness 251 ′ of the dielectric in the image 262 ( FIG. 5B ) is maintained according to the invention. This allows process flow steps (e.g., such as the dielectric layer formation in FIG. 4C above) to be adjusted to provide the desired final thickness, without having to compensate for etch-related reduction as experienced in the past. Further, the via profiles are better in the image 262 than in the conventional case of the image 250 (e.g., less bowing in FIG. 5B than in FIG. 5A , corresponding to 231 in FIG. 4J vs. 20 ′ in FIG. 1F , for example). Furthermore, the CDs in the image 262 of FIG. 5B are smaller than those in FIG. 5A .
[0054] By way of further example, FIGS. 5C and 5D similarly illustrate the effectiveness of in-situ ashing in accordance with one or more aspects of the present invention as compared to conventional techniques. In particular, FIG. 5C is a cross sectional SEM image 266 of vias 267 formed with in-situ etch-stop etching, conventional ex-situ ashing and wet solvent clean. FIG. 5D , on the other hand, depicts such vias formed as a result of in-situ ashing according to one or more aspects of the present invention. More particularly, FIG. 5D is a cross sectional SEM image 270 of single damascene vias 271 formed at the same scale as FIG. 5D and with in-situ etch-stop etching, in-situ ashing and wet solvent clean, where the vias 271 are formed in the same ILD film stack as the vias 267 of FIG. 5C . In the example shown in FIG. 5D , the in-situ ashing occurs in the same processing chamber as the in-situ etching. It will be appreciated, however, that the in-situ ashing could also occur in the same tool, but in a different chamber than the in-situ etching (with wafer transferred under vacuum) in accordance with one or more aspects of the present invention. It can be seen that the same, if not an improved, level of quality results from the in-situ ashing as compared to conventional ex-situ ashing. For example, the profile of the vias 271 in FIG. 5D is the same if not better than those 267 of FIG. 5C and are substantially uniform with very little, if any, bowing.
[0055] FIGS. 5E, 5F and 5 G are top view SEM images 574 , 576 , 578 , respectively, that also illustrate the effects of in-situ ashing according to one or more aspects of the present invention versus conventional ex-situ ashing. For example, the SEM image 574 in FIG. 5E is a top view of vias 575 formed with conventional ex-situ ash processing. It can be seen that a generous amount of residue 577 exists around the vias (and more particularly down in the vias along the sidewalls) and on the top surface between the vias. FIGS. 5F and 5G , on the other hand, illustrate vias formed with in-situ ashing according to one or more aspects of the present invention. The vias 579 in FIG. 5F were ashed in the same tool and in the same chamber as other processing (e.g., etching), whereas the vias 580 in FIG. 5G were ashed in the same tool, but in a different chamber. Regardless, it can be seen that less residue 581 , 582 (if any) is present in FIGS. 5 F and 5 G, respectively, as compared to the ex-situ ash case presented in FIG. 5E .
[0056] It is to be appreciated that one or more aspects of the present invention (e.g., in-situ low power, low pressure ash) allows a RIE plasma to be utilized. This, among other things, facilitates the decreased CD bias from in-situ ash as compared to conventional ex-situ ash due to, among other things, a substantially anisotropic nature of the RIE plasma. Additionally, adding O 2 to the low power ash facilitates oxidizing possible Cu residues left over from the in-situ etch-stop etch. The oxidized Cu residues can then be more easily removed by the subsequent wet clean operation further facilitating the improved residue removal.
[0057] According to another aspect of the invention, methods are provided for forming a dual damascene interconnect structure overlying an existing interconnect structure in a semiconductor wafer, which may be employed in a via-first implementation or in a trench-first dual damascene implementation to provide electrical coupling to a conductive feature in the existing interconnect structure. An exemplary via-first method 300 is illustrated in FIGS. 6A and 6B . While the method 300 is illustrated and described below as a series of acts or events, it will be appreciated that the present invention is not limited by the illustrated ordering of such acts or events. For example, some acts may occur in different orders and/or concurrently with other acts or events apart from those illustrated and/or described herein, in accordance with the invention. In addition, not all illustrated steps may be required to implement a methodology in accordance with the present invention. Furthermore, the methods according to the present invention may be implemented in association with the formation and/or processing of structures illustrated and described herein as well as in association with other structures not illustrated.
[0058] Beginning at 302 , the method 300 comprises forming an etch-stop layer over an existing interconnect structure at 304 , forming a low-k dielectric layer over the etch-stop material at 306 , and optionally forming a first BARC layer at 308 over the dielectric layer, in a manner similar to the acts 104 - 108 above. A via resist mask is then formed and patterned at 310 , having an opening in a prospective via region of the wafer. An in-situ process flow 312 is then performed in accordance with this aspect of the invention, wherein a via cavity is formed through the BARC, dielectric, and etch-stop layers, for example, concurrently in a single RIE tool. At 314 a , the exposed BARC layer is etched, using the patterned resist as a mask, and a via main etch is performed at 314 b , creating a via cavity or opening in the dielectric layer. A via over-etch process is then performed at 314 c to remove the remaining portion of the dielectric material in the via cavity and to expose a portion of the underlying etch-stop layer material. At 316 , an etch-stop layer etch (e.g., an RIE etch operation) is then performed to remove the exposed portion of the etch-stop material, thereby extending the cavity and exposing a conductive feature in the underlying interconnect structure.
[0059] As with the above single damascene case (e.g., FIG. 3 above), substantially no other processing is performed between the via etch acts of 314 a - 314 c and the etch-stop etch of 316 . The via etch at 314 a - 314 c and the etch-stop etch at 316 may, but need not be, performed in-situ within a single RIE etch tool, wherein other implementations are possible within the scope of the invention, in which the etch-stop etch at 316 is performed concurrently with the via etch 314 or immediately thereafter. In addition, the invention also contemplates alternative implementations in which the via and etch-stop etch acts are performed with substantially no processing steps therebetween. For example, no ashing or wet etch operations are performed between the exemplary via etch 314 and the etch-stop layer etch at 316 in the illustrated method 300 . In this regard, the exemplary method 300 provides coverage of the upper dielectric surface during the etch-stop etch at 316 because the patterned resist mask remains until after the etch-stop etch 316 .
[0060] Although the exemplary method 300 provides in-situ etching of the via cavity through the dielectric layer (e.g., 314 ) and etch-stop etching to extend the via cavity through the etch-stop layer, other implementations are possible within the scope of the present invention where these or equivalent acts are performed in different etch tools. Moreover, one or more process acts may be performed between the via etch and the etch-stop etch acts in accordance with the invention where the dielectric layer is covered during the etch-stop etch. In the illustrated method 300 , the resist mask from the via etch steps remains during the etch-stop etch 316 . However, other implementations are possible within the scope of the invention, wherein the all or a portion of the dielectric is covered by any means during the entirety of, or during a portion of, the etch-stop etch 316 . Further, although the exemplary method 300 provides a multi-step etch (e.g., 314 b , 314 c ) through the dielectric layer, other implementations are contemplated, wherein any of the BARC etch, the via etch, and/or the etch-stop etch acts may be single step or multi-step operations, within the scope of the present invention.
[0061] In the exemplary method 300 , the etching acts 314 a - 314 c and 316 are performed in a single RIE etch tool, with appropriate etch chemistries being changed accordingly, to remove material from the exposed layer (e.g., from the BARC layer, then the dielectric layer, and then the etch-stop layer). Furthermore, while illustrated and described with respect to organic BARC materials, OSG type low-k dielectric material, and SiC or SiN etch-stop layer materials, any appropriate materials may be employed in forming these layers in accordance with the invention, where appropriate etch chemistries and selectivities may be selected in performing the etch operations 314 - 316 to fabricate the via cavity. In the illustrated method 300 , the main etch at 314 b removes the majority of the dielectric material in the cavity, leaving about 1000-2000 Å of OSG low-k dielectric material remaining. The process parameters are then switched to the over-etch at 314 c , which is time controlled to stop on the etch-stop layer, wherein the exemplary via over-etch at 314 c has a higher selectivity to the etch-stop layer than does the via main etch at 314 b.
[0062] With the etch-stop layer exposed, the etch process is again adjusted for etching the etch-stop material at 316 with a selectivity to the underlying (e.g., pre-existing) interconnect structure, so as to expose an underlying conductive feature (e.g., copper structure). As with the single damascene case, the dual damascene method 300 preserves the resist mask over the dielectric layer while etching the exposed portion of the etch-stop layer at 316 , since there is no intervening ashing or wet etch process to remove the via resist mask. Consequently, etch-stop etch related damage to the dielectric material is mitigated or avoided during the etch-stop etch at 316 , by which the via CD and profile are protected.
[0063] After the in-situ process at 312 , the method 300 proceeds to 318 , where an ashing operation is performed to remove the resist mask initially formed at 310 , and the BARC material deposited at 308 . As discussed above with regard to the single damascene case, according to one or more aspects of the present invention, the ashing 318 is performed in-situ in the same tool either in the same or a different chamber. The in-situ ashing allows a RIE plasma to be utilized to more effectively remove residues. Similarly, oxygen can be added to facilitate removing Cu residues. Also, the in-situ process allows the via etch 314 a - 314 c , etch-stop etch 316 and ash 318 to be done more efficiently, cost effectively and with less actions. For example, the ashing 318 can be performed at a power of about 150 to 400 W and a pressure of about 20 to 80 mT. Further, the operation 318 may be performed for a time of about 15 to 60 seconds with an oxygen (O 2 ) flow of about 100 to 500 sccm and at a chuck temperature of about 20 to 40 degrees Celsius. Other ash chemistries such as H 2 /Ar, H 2 /He, H 2 /N 2 O 2 /H 2 , O 2 /N 2 can also be used. As a matter of reference, in-situ acts 314 a , 314 b , 314 c , 316 and 318 are depicted as 312 ′ in the exemplary flow 300 . A wet clean operation is then optionally performed at 320 to remove any residue remaining from the RIE etch and ash acts.
[0064] Referring also to FIG. 6B , a second BARC layer is then formed at 322 , and a trench resist mask is formed and patterned at 324 . A two step trench etch 326 is then performed, comprising a trench BARC etch at 328 a and a patterned trench main etch at 328 b . Thereafter at 330 , another ashing operation is performed to strip the trench resist mask and the second BARC layer, followed by another wet clean operation at 332 . The ashing operation 330 is once again performed in-situ according to one or more aspects of the present invention (e.g., as set forth above with regard to operations 318 , 118 ). As a matter of reference, in-situ acts 328 a , 328 b and 330 are depicted as 326 ′ in the exemplary flow 300 . It will be appreciated, however, that the ashing 330 can also be performed according to conventional ex-situ ash processes.
[0065] A diffusion barrier is then formed at 334 , and a seed copper layer is deposited over the diffusion barrier at 336 , to facilitate subsequent copper filling of the via and trench cavities. The trench and via cavities are then filled with copper using an ECD process at 338 , and a CMP process is performed at 340 to planarize the upper surface of the device, before the method 300 ends at 342 . It is noted that alternative implementations are possible within the scope of the invention, wherein the trench is formed prior to formation of the via cavity, wherein the via etch and etch-stop etch operations are performed concurrently, and/or with substantially no processing operations therebetween, and/or with the dielectric layer at least partially covered during the etch-stop etch, as described above.
[0066] Referring now to FIGS. 7A-7N , another exemplary wafer 402 is illustrated undergoing dual damascene interconnect processing in accordance with the invention. FIG. 7A illustrates the wafer 402 at an intermediate stage of fabrication, comprising a silicon substrate 404 , in which a conductive silicide structure 405 is formed. An initial contact layer is formed over the substrate 404 , comprising a dielectric 406 with a tungsten contact 407 extending therethrough, and electrically contacting the silicide 405 . An existing interconnect structure overlies the contact layer, including an etch-stop layer (not shown) and a dielectric 408 in which a conductive feature 410 is formed, such as copper trench metal, to provide electric coupling to the tungsten contact 407 . As with the single damascene methods of the invention, the dual damascene processing of the present invention may be carried out in fabricating an interconnect structure over an initial contact structure, such as illustrated in FIG. 7A , and/or in forming such a structure over another single or dual damascene structure in a multi-layer interconnect network structure.
[0067] A SiN or SiC etch-stop layer 412 is formed over the existing interconnect dielectric material 408 and over the conductive feature 410 , for example, to a thickness 412 ′ of about 600-800 Å, and a dielectric layer 414 , such as a low-k OSG dielectric material or the like, is formed over the etch-stop layer 412 to a thickness 414 ′ of about 7000-8000 Å. An organic BARC layer 416 overlies the dielectric 414 , having a thickness of about 600-800 Å, and a via resist mask 418 is formed over the BARC layer 416 , having an opening 420 in a prospective via region. In FIG. 7B , a via BARC etch process 422 is performed to remove the BARC layer 416 in the via region 420 . In FIG. 7C , a via main etch process 424 is used to form a via cavity 426 in the dielectric layer 414 , leaving a thickness 428 of dielectric material 414 unetched at the bottom of the via cavity 426 (e.g., about 1000-2000 Å). A via over-etch process 430 is employed in FIG. 7D to further form the cavity 426 through the rest of the dielectric layer 414 , stopping on and exposing a portion of the underlying etch-stop layer 412 . An etch-stop etch 432 is performed immediately thereafter (e.g., concurrently with the over-etch 430 ) in FIG. 7E to expose the underlying conductive contact 410 .
[0068] Thereafter in FIG. 7F , a resist ashing process 434 is used to remove the remaining resist mask 418 layer and the BARC layer 416 , and a wet clean operation 436 is performed in FIG. 7G . According to one or more aspects of the present invention, the ashing process 434 is performed in-situ in the same processing tool that performs the other operations (e.g., etching) in either the same or a different processing chamber within the tool. The ashing 434 is performed in an efficient and cost effective manner by utilizing a RIE plasma and oxygen that more effectively removes Cu and other residues as compared to conventional ex-situ ashing. Additionally, the ashing can be done at a power of about 150 to 400 W and a pressure of about 20 to 80 mT, for example. Further, the operation 434 may be performed for a time of about 15 to 60 seconds with an oxygen (O 2 ) flow of about 100 to 500 sccm and at a chuck temperature of about 20 to 40 degrees Celsius. Other ash chemistries such as H 2 /Ar, H 2 /He, H 2 /N 2 O 2 /H 2 , O 2 /N 2 can also be used.
[0069] As illustrated in FIG. 7H , a second BARC layer 438 is then formed over the wafer 402 , wherein some of the BARC material 438 ′ is formed at the bottom of the via cavity 426 . A trench resist mask 440 is formed over the BARC layer 438 , and a trench BARC etch process 442 is performed in FIG. 7I to remove the BARC material in the prospective trench region of the wafer 402 , with a portion of the BARC 438 ′ remaining in the via cavity 426 . Thereafter in FIG. 7J , an RIE trench etch process 444 is employed to form a trench cavity 446 in the dielectric layer 414 , wherein a certain amount of residual BARC material 438 ′ may still remain in the bottom of the via cavity 426 during the trench etch process 444 . Following the trench etch process 444 , another ashing process 448 is performed in FIG. 7K to remove the trench resist mask 440 and any remaining BARC material (e.g., BARC 438 ′ in the via cavity 426 ), after which another wet clean process 450 is performed in FIG. 7L . According to one or more aspects of the present invention, the ashing process 448 is performed in-situ rather than ex-situ, such as is described above with regard to 434 and 234 . The ashing operation 448 can also be performed according to conventional ex-situ ash processes.
[0070] As illustrated in FIG. 7M , a copper diffusion barrier layer 452 and a copper seed layer 454 are formed, after which copper fill material 456 is deposited over the wafer 402 to fill the trench and via cavities 446 and 426 , respectively, for example, using an ECD process. Thereafter in FIG. 7N , the wafer 402 is planarized, for example, using a CMP process, to complete the conductive dual damascene trench and via structure. One or more subsequent interconnect levels or layers may thereafter be constructed over the structure of FIG. 7N , for example, using the above-described or other single and/or dual damascene fabrication techniques. Any number of such layers or levels may be fabricated in accordance with the present invention, to provide electrical coupling to the conductive feature (e.g., silicide structure 406 ) in the wafer 402 .
[0071] Although the invention has been illustrated and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings and the present invention is intended to include the same. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms “including”, “includes”, “having”, “has”, “with”, or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.” Also, the term “exemplary” as utilized herein merely means an example, rather than the best. | One or more aspects of the subject disclosure pertain to forming single or dual damascene interconnect structures in the fabrication of semiconductor devices. The interconnect structures are formed in manners that mitigate one or more adverse effects associated with conventional techniques. One or more aspects of the invention may be employed, for example, to facilitate better via critical dimension (CD) control, improve selectivity of etch-stop layer to inter layer dielectric (ILD) and/or intra-metal dielectric (IMD) material, and/or to simplify and make the fabrication process more efficient and/or cost effective. | 7 |
FIELD OF THE INVENTION
The present invention relates directly to lift systems on agricultural implements and, more specifically, to a depth control actuation system for such implements.
BACKGROUND OF THE INVENTION
Agricultural implements with hydraulically actuated depth or lift systems often include depth control systems such as shown in commonly assigned U.S. Pat. Nos. 5,427,184 and 5,988,293. A typical system may include a valve which is activated to stop vertical movement of the frame as the implement is lowered to a selected working position.
Many hydraulically controlled agricultural implements utilize a single point depth control system wherein implement depth is monitored and adjusted at a single location on the implement. Typically, a plunger bracket assembly is slidably mounted on an actuator tube operably connected to the implement rockshaft. A plunger on the assembly contacts a poppet valve to stop fluid flow from the hydraulic lift cylinders at a preselected depth. To adjust depth, a set screw on the bracket assembly is loosened, and the bracket assembly is slid along the tube. The screw is tightened to secure the assembly at the desired location along the tube. Normally the amount of depth adjustment is small. When the set screw is unthreaded, the bracket is loosened from the tube and slides on the tube, often to a wrong location. The bracket has to be manually moved, and the amount of adjustment has to be determined visually. When the set screw is tightened, the bracket often changes location. Several trials may be required to achieve the desired position. Therefore, depth adjustment is often imprecise, difficult to repeat, and time consuming.
In another type of depth control, which is the subject of commonly assigned U.S. Pat. No. 5,427,184, a long crank is provided to adjust a linkage adjacent the depth control cylinder. Although such a device has the advantage of directly monitoring cylinder extension and retraction, the valve and linkage components are more complicated, expensive and difficult to access, and are subject to damage by crops and soil passing through the machine. A further type of control is shown in commonly assigned U.S. Pat. No. 5,988,293. Although these types of devices have alleviated some of the problems associated with depth control structures, most require complicated and expensive linkages, particularly if the depth adjustment is conveniently located for the operator. Wear and hysteresis limit the ability of such structures to provide accurate and repeatable depth control functions.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide an improved depth control system for an implement. It is a further object to provide such a system which overcomes most or all of the aforementioned problems. It is still another object to provide such a system which is particularly useful with single point depth control structures.
It is another object of the invention to provide an improved depth control system for an implement having reduced hysteresis and improved repeatability compared to at least most previously available systems. It is a further object to provide such a system which is less complicated, easier and less expensive to manufacture, and easier to access than most systems.
A depth control system includes a valve and actuator mounted directly to the pivotal connection areas of a hydraulic cylinder that controls height. Cylinder motion therefore directly controls valve actuation independently of complicated linkages to reduce the size and cost of the system and substantially overcome hysteresis problems. These and other objects, features and advantages of the invention will become apparent from the description below in view of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a portion of an implement with height control structure.
FIG. 2 is an enlarged perspective view of the height control structure on the implement of FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 and 2, therein is shown a portion of an agricultural implement 10 having a tool-supporting frame 12 supported for forward movement over a field by lift wheel structure 16 . Hydraulic cylinder structure 20 is connected through a lift linkage 22 to the wheel structure 16 to selectively raise and lower the frame 12 . Tools (not shown) can be mounted on the frame for vertical movement therewith between field-working and transport positions. Depth control for soil engaging elements is provided by the vertical movement of the frame 12 .
A rockshaft 24 extending transversely to the forward direction of the travel of the implement is rotatably mounted on the frame 12 by bearing block support structure 26 . A lever or arm 28 is fixed to and extends upwardly from the rockshaft 24 closely adjacent the support structure 26 for rotation with the rockshaft about a transversely extending axis. The lift linkage 22 includes a tension link 32 pivotally connected at a forward end 34 to the arm 28 . The link 32 includes an aft end 36 pivotally connected to an upright arm 38 on the wheel structure 16 . As the forward end 34 of the link 32 is moved in the fore-and-aft direction, the wheel structure 16 is pivoted relative to the frame 12 to raise and lower the frame.
The cylinder 20 includes a rod end 40 pivotally connected by elongated cylinder pin structure 42 to the rockshaft arm 28 rearwardly and below the pivotal connection at the forward end 34 to the arm 28 . The cylinder 20 includes a base end 44 pivotally connected by a second elongated cylinder pin structure 46 to an aft end of a cylinder support bracket structure 48 . The cylinder support bracket 48 includes an angle support 50 having a forward end connected to the bearing block support structure 26 . The aft end of bracket 48 is connected by a U-bolt assembly 52 to a transversely extending frame tube 12 t.
The rod and base ends of the cylinder 20 are connected by hydraulic lines 56 and 58 , respectively, to a controlled source of hydraulic fluid for extending and retracting the cylinder. The base end line 58 is connected to a lower output port on a control valve 60 which is mounted directly on the rod end cylinder pin structure 42 . The control valve 60 includes a forwardly directed inlet port connected through a manual lock-up valve 66 and fluid line 68 to a controlled source of hydraulic fluid on the towing vehicle (not shown). The control valve 60 includes an outwardly biased valve actuator 70 , which when in the position shown in FIG. 2 allows generally unrestricted flow between the base end of the cylinder 20 and the source. The actuator 70 , when depressed against the bias, blocks flow between the cylinder 20 and the source. The valve 66 is normally open during field operations but can be closed to lock the cylinder 20 in a selected position such as the extended position during transport of the implement 10 .
Valve actuator structure 80 is supported from the rod and base ends 40 and 44 of the cylinder 20 and includes a tube or guide 82 slidably received through mating apertures in the cylinder pin structures 42 and 46 . A spring 84 is captured on the base end of the guide 82 between pin and washer structure 86 and the pin structure 46 , and an aft end pin 88 prevents the guide 82 from sliding forwardly out from the aperture in the pin structure 46 . The forward end of the guide 82 extends through and freely slides within the aperture in the rod end pin structure 42 while the base end of the guide normally remains fixed relative to the base end pin structure 46 . In case of binding, over-retraction of the cylinder 20 or improper adjustment of the actuator structure 80 , the spring 84 can compress to allow the guide 82 to slide rearwardly relative to the pin structure 46 to prevent bending or breaking of the actuator structure 80 .
The actuator structure 80 includes a plate or contact member 90 slidably supported on the guide 82 . An adjustment rod 94 is rotatably supported from the guide 82 by a forward rod bracket 96 and an aft rod bracket 98 below and parallel to the guide 82 . The guide 82 is supported generally parallel to cylinder axis 20 a and remains parallel to the cylinder axis with extension and retraction of the cylinder. The rod 94 has a threaded central portion received through a threaded aperture at the lower end of the contact member 90 . By rotating the rod 94 , the contact member 90 can be adjustably positioned along a central portion of the guide 82 . Indices 102 are provided along the central portion to provide the operator with a visual indication of the adjusted position of the contact member 90 . As the cylinder 20 is retracted by opening the hydraulic line 68 to reservoir, the frame 12 lowers. The valve 60 moves with the rod end pivot structure 42 rearwardly relative to the contact member 90 as the forward end of the guide slides through the pin structure 42 . The valve 60 and contact member 90 converge generally along a straight path parallel to the cylinder axis 20 a until the member 90 depresses the valve actuator 70 and blocks flow from the base end of the cylinder 20 through the line 58 to establish an adjusted frame position dependent on the adjusted position of the contact member 90 along the guide 82 . To raise the frame, the operator pressurizes the line 68 using a control valve on the towing vehicle and a one-way check valve (not shown) in the valve 60 allows hydraulic fluid to enter the base end of the cylinder 20 to extend the cylinder rod and raise the frame.
Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims. | A depth control system particularly useful for single point depth control on an agricultural implement includes a valve and actuator mounted directly to the pivotal connection areas of a hydraulic cylinder that controls height. Cylinder motion directly controls valve actuation independently of complicated linkages to reduce the size and cost of the system and substantially overcome hysteresis problems. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a radiation delivery system, and in particular to a radiation delivery system used in the non-invasive treatment of human body tissue.
2. Description of the Prior Art
Systems which employ an external radiation source to modify internal body tissue are well known. Examples of such systems include radiotherapy systems, in which an external source delivers nuclear radiation to the body for example to destroy tumors; and ultrasound systems, in which an external source delivers ultrasound to the body for example to destroy kidney stones.
Problems with such systems are that it is often difficult to accurately locate an internal target site which is to receive the radiation and that it is sometimes difficult to maintain delivery of the radiation to that site. These problems may be particularly acute when the site itself is cont inuously moving relative to the body and to the radiation source. This can occur when the site is located on a moving organ such as the heart. In order for the physician to be sure that the internal target site receives a useful dose of radiation an area of tissue much larger than the site itself often may be irradiated. This can result in unnecessary damage to healthy tissue.
A further problem is that any unexpected movement of the body may result in the target site receiving less than the expected dose of radiation.
One known device which attempts to address at least some of these problems is described in the European Patent 0 400 196. This document discloses a radiation delivery system in which an ultrasound source is linked to an X-ray device. The X-ray device is used to locate the target site within the body and to provide information to control the delivery of ultrasound to that site. At least two X-ray images are required each time 3-dimensional position information is needed. Thus both the physician and the patient may be exposed to potentially hazardous ionizing radiation. This may be particularly problematical if the system were to be employed to monitor a movable target site as this is likely to require a large number of X-ray images to be made during a single procedure.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a radiation delivery system in which at least some of the aforementioned problems associated with the known radiation delivery systems are reduced.
The above object is achieved in accordance with the principles of the present invention in a system for delivering radiation to an intracorporeal target including a controllable extracorporeal radiation source and a locating system for controlling the radiation source to deliver radiation to the target site, the locating system including a reference element positionable at an intracorporeal site having a known spatial relationship with the target site, the reference element being configured to provide an output signal related to its location for use in controlling the radiation source.
Thus the radiation source, which may be formed as an array of radiation supplies operable in a group or separately, can be automatically controlled, for example by moving the focus of the source or by varying the level of radiation from the source, to deliver radiation to a target site and so minimize the destructive irradiation of tissue surrounding the target site.
Moreover, the use of an internal reference element which can be positioned at or near the target site means that the reference element can move as the target site moves. This allows the radiation source to track the movement of the target site so that the risk of damaging healthy tissue is further reduced.
The radiation delivery system according to the present invention may also include an element, positionable within the body, for modifying the path of the radiation within the body. This provides a greater control over the delivery of radiation to the target site. For example, a defocusing reflector may be used, perhaps mounted on or in the reference element, to reflect radiation from the radiation source over an area larger than that of the incident beam.
Simply, the reference element of the location system may include a radiation detector which provides an output dependent on the presence of radiation from the radiation source. The detector can be advantageously arranged to provide an output signal directly proportional to the level of detected radiation. In this way the radiation source may be controlled to more accurately deliver radiation to the target site than if the detector detected only the presence or absence of incident radiation.
The location system may additionally or alternatively include a non-ionizing radiation transmitter and receiver elements cooperating therewith to sense the position in space of a reference element which includes either the transmitter or receiver element. An output signal dependent on the sensed position of the reference element may then be generated to control the radiation source. This has an advantage that harmful radiation need not be present until the radiation source is focused on the target site.
Location systems that can sense the position of catheters within a body by using non-ionizing radiation are well known in the art. Examples of such systems are described in U.S. Pat. Nos. 5,042,486 and 5,391,199, both of which describe systems which employ electromagnetic or ultrasound radiation to track a catheter, and in PCT Application WO 95/09562, which describes a system for tracking a catheter using a magnetic field. All such systems work by equipping the catheter to be tracked with a radiation receiver or transmitter and having a complementary transmitter or receiver positioned outside the body. Radiation received from the transmitter can then be analyzed to provide information on the position of the catheter within the body. This information may then be used by a physician to guide a so called "minimally invasive medical tool", such as an ablation catheter, a mapping catheter or an endoscope through the body to a target site where surgical treatment is to be carried out.
In contrast to these known systems, the use in the inventive location system of a reference element which combines both a detector to detect radiation from the radiation source and also a position sensor allows the output from both the detector and sensor to be employed to control the radiation source. In this way there may be a greater certainty that the target site will be irradiated.
In such a system the radiation from the radiation source and the non-ionizing radiation used to sense position may both be ultrasound, perhaps of different frequencies to assist in the identification of their origin. This has the advantage that the reference means may be simplified in ways common in the art so that the device used in sensing the position of the reference element is also used to detect incident radiation from the radiation source.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic representation of a first system embodiment according to the present invention.
FIG. 2 shows a schematic representation of the tip of a reference catheter usable in the system of FIG. 1.
FIG. 3 shows a schematic representation of a second system embodiment according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a target site I is situated within the heart 2. A location system includes an internal reference catheter 3 having an ultrasound transceiver 4 disposed proximate its tip; a cooperable receiver 5 and a signal processor 6, which may be a suitably programmed computer. The location system provides to the cooperable ultrasound radiation source 8 an output signal dependent on the sensed position of the transceiver 4. The transceiver 4 is configured to serially operate both as a transmitter, to provide a location signal for the receiver 5, and as a receiver, to provide an output signal proportional to the level of radiation received from the radiation source 8.
The transceiver 4 of the catheter 3 is positioned at a known distance from the target site 1 to move as the target site 1 moves, for example as the heart 2 beats (shown as 1', 2' and 4'). This arrangement can then be used to locate the target site 1 at any time in the cardiac cycle. The accurate positioning of the catheter 3 within the heart 2 can be done using the location system 4, 5, 6 in a manner known in the art, for example as described in U.S. Pat. No. 5,042,486.
In use, the signal processor 6 receives a signal from the receiver 5 which is dependent on the relative positions of the transceiver 4 and the receiver 5 and analyzes the signal to sense the position of the transceiver 4 within the body 7. The processor 6 then provides a control signal to the external radiation source 8 dependent on this sensed position. The radiation source 8 is provided with control means, responsive to the control signal, to control the movement of the incident radiation beam 9 in order to maintain focus on the target site 1 as the heart 2 beats.
Alternatively, the focus of the beam 9 can remain fixed and the control signal can be employed to switch the beam 9 on and off as the target site 1 passes through the beam 9 during a heart beat.
In a modification to this embodiment the output of a cardiac monitor, such as an ECG system, (shown in broken lines and composed of an ECG electrode 11 and an ECG monitor 10 is also used to control the output of the radiation source 8. This additional control signal can ensure that irradiation occurs at a known point in every cardiac cycle. Here the location system 4, 5, 6 may be used to move the focus of the beam to a predetermined position in which the target site 1 will be irradiated by the beam 9 for at least a part of the cardiac cycle. Once positioned the operation of the radiation source 8 is determined by the output of the cardiac monitor 10, 11 so that the beam 9 is on only for some or all of that part of the cardiac cycle in which the target site 1 lies within the beam 9.
Before the site is irradiated the radiation delivery system may be calibrated in order to correlate the position of the heart 2 with the output from the cardiac monitor 10, 11. The location system may be used for this purpose by arranging for the position of the transceiver 4 to be sensed at known points in the cardiac cycle (determined using the cardiac monitor 10, 11). Once this correlation has been determined then the part of the cardiac cycle during which the target site 1 will lie within the beam 9 can be calculated and the output from the cardiac monitor 10,11 used to switch the beam 9 on and off as appropriate. The transceiver 4, operating as a receiver, can be used to provide an output signal dependent on the level of incident radiation from the beam 9. This signal can be used as a safety precaution so that the beam 9 is switched to maximum intensity only when there is an output signal from the transceiver 4.
A portion of a catheter 3, which may be used in the above described system, is shown in FIG. 2. A cylindrical transceiver 4 is positioned about the catheter 3 and proximal its tip. A curved radiation reflector 12 is positioned inside the catheter 3, between its tip and the transceiver 4. This reflector is curved so as to be able to defocus and reflect incident radiation 9 from the source 8 towards the target site 1.
A further embodiment of a system according to the present invention is shown in FIG. 3 in which items similar to those in FIG. 1 have the same reference numerals.
In FIG. 3 the target site 1 is again within the heart 2 and 15 a catheter 3 is provided having proximal its tip a nuclear radiation detector 13. The detector 13 is adapted to provide an output signal proportional to the intensity of incident radiation from a nuclear radiation source 14. Conveniently the output signal is in the form of an electric current which passes through a wire 15 within the catheter 3 to the radiation source 14 to control the intensity of the beam 9.
In use, the output of the beam 9 is arranged to have a default intensity which is less than that to be used to irradiate the target site 1. As the output signal from the detector 13 increases above a predetermined level, for example as the focus of the source 14 is manually moved toward the target site or as the target site 1 passes through the beam when the heart 2 beats, the intensity of the beam 9 is increased to its treatment level. As the output from the detector 13 decreases below the same or a different predetermined level the intensity of the beam 9 is reduced to its default level. In this way the radiation induced damage to healthy tissue which surrounds the target site 1 can be reduced.
It will be apparent to those skilled in the art that other combinations of radiation detector, position sensor, cardiac monitor or other monitor may be employed or that the analysis of signals and the control of the radiation source may be done by using a separate, suitably programmed computer or by using dedicated hardware which may be located within any monitor or the radiation source of the delivery system while remaining within the scope of the invention as claimed.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventor to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of his contribution to the art. | A system for delivering radiation to an intracorporeal target site has a controllable external radiation source 8 and a cooperable location system for controlling the radiation source to deliver radiation to the internal target site. The location system includes a reference element positionable at an internal site having a known spatial relationship with the target site, this element being configured to provide an output signal related to its location for controlling the radiation source. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority from, and incorporates by reference the entire disclosure of, Japanese Patent Application (1) No. 2004-338883, filed on Nov. 24, 2004.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a processing controller, a data communication apparatus such as a personal computer, and a program for the controller and apparatus. Particularly, the invention relates to a processing controller, a data communication apparatus that incorporates a software modem to stabilize a connection of a communication line between data communication apparatuses, and a program for the controller and apparatus.
2. Description of the Related Art
In order to maintain a stable operation of a communication line while the communication line is being connected to a bulletin board system (BBS) or other data communication apparatus, telecommunication equipment such as a modem always monitors line quality, and automatically resets communication functions and performance such as a communication speed and a modulation system (i.e., retraining, and rate renegotiation). With the increase in the operating speed of CPUs in recent years, software is being developed for telecommunication equipment such as modems. The bulletin board system conventionally refers to the whole of personal computer communication services, and nowadays refers to a data communication apparatus provided in a Web site mode on the Internet. The retraining refers to a negotiation operation that two sets of telecommunication equipment (i.e., modem) carry out to determine the setting of communication functions and performance by mutually exchanging information about communication speed, modulation system, error correction function, and data compression procedure, to establish communications. Particularly, negotiation to reset a communication speed is called rate renegotiation. The retraining is the processing to renegotiate communication functions and performance currently in use, without re-connecting the mutually-connected two modems. The retraining occurs when a line state changes as a result of increase in the amount of static electricity on the line, for example. Usually, this processing takes a few seconds.
Patent literature 1 discloses an information processor that restricts power consumption of a CPU by variably controlling the clock frequency of the CPU using a software modem, that is, a software system for a computer main body to execute a part of the functions of a modem that connects between the computer and an analog communication line. The patent literature 1 also discloses an information processor that restricts communication errors such as a connection refusal and a timeout, by variably controlling the clock frequency following a necessary CPU load that changes according to a negotiation state.
Patent literature 2 discloses a software modem for a data communication apparatus, in which, when there is an instruction to process a specific application with a higher processing priority than that of a modem processing of resetting communication functions and performance, the software modem starts processing this specific application even when the modem processing is being carried out. In order to properly execute the modem processing while properly executing the processing of other applications, the software modem changes a communication speed according to the number of applications being started, the state of the load of the applications being started on the CPU, and the time required for the modem processing.
Patent literature 1: Japanese Patent Application Unexamined Publication No. 11-296251 (paragraphs 0009 to 0015, 0019, 0022, 0024 to 0029, and 0066 to 0068, and FIG. 2 and FIG. 3).
Patent literature 2: Japanese Patent Application Unexamined Publication No. 2002-325114 (paragraphs 0002, 0005, 0006, 0009 and 0010).
Usually, the modem operates in a quiet mode after the line is connected. A user does not recognize that communication is now being reset. The modem executes a reset to stably operate communication. The software modem is most unstable during the resetting of communication such as a resetting of a modulation system and a communication speed. The load on the CPU is largest during this resetting. If, while the CPU is being applied with large load, the CPU receives an interrupt request to process a specific application having a higher priority than that of a retraining processing and, for example, when there is an interrupt request to start a word processor or reproduce a DVD that applies large load on the CPU, the CPU usually executes the interrupt processing with priority over the retraining processing. Therefore, the retraining processing is not executed. When this processing continues for a long time based on the interrupt request, the CPU cannot communicate with the other communication apparatus to reset communication. Consequently, the retraining processing cannot be carried out normally, and the line is disconnected.
The information processor described in the patent literature 1 variably controls the clock frequency following the necessary load on the CPU that changes based on the negotiation state. On the other hand, the software modem described in the patent literature 2 changes the communication speed according to the number of applications being started, the state of the load of the applications being started on the CPU, and the time required for the modem processing. However, the above operations do not solve a problem of a line disconnection that occurs when the CPU executes the interrupt processing with priority over the retraining processing during the resetting of communication functions and performance which applies a large load to the CPU.
SUMMARY OF THE INVENTION
In order to solve the above problem, the present invention provides a processing controller, a data communication apparatus incorporating a software modem, and a program for these apparatuses that can securely reset communication functions and performance such as a modulation system and a communication speed and can maintain stable connection of a communication line, even when a CPU is instructed to execute interrupt processing that has priority over retraining processing during the resetting operation.
In order to achieve the above object of the invention, there is provided a processing controller for a data communication apparatus having a processing section that executes at least a part of communication processing of a communication controller and that executes processing other than the communication processing. The processing controller has an interrupt request blocking section that blocks, during execution of a processing relevant to information exchange concerning a communication condition for the communication controller to carry out a communication processing, an interrupt request to the processing section with priority over the processing relevant to information exchange.
In order to achieve the above object of the invention, there is provided a data communication apparatus having a processing section that executes at least a part of communication processing of a communication controller and that executes processing other than the communication processing. The data communication apparatus has an interrupt request blocking section that blocks, during execution of a processing relevant to information exchange concerning a communication condition for the communication controller to carry out communication processing, an interrupt request to the processing section with priority over the processing relevant to information exchange.
In the data communication apparatus, an input device carries out the interrupt request to the processing section with priority over the processing relevant to information exchange during the execution of this processing.
The data communication apparatus displays a message to the effect that the operation carried out by the input device is invalid during the execution of the processing relevant to information exchange.
In order to achieve the above object of the invention, there is provided a program that is executed in a data communication apparatus having a processing section that executes at least a part of communication processing of a communication controller and that executes processing other than the communication processing. The program functions as an interrupt request blocking section that blocks, during execution of a processing relevant to information exchange concerning a communication condition for the communication controller to carry out a communication processing, an interrupt request to the processing section with priority over the processing relevant to information exchange.
According to the processing controller, the data communication apparatus, and software of the present invention, operation that gives a large load to the CPU can be blocked while the software modem is resetting communication functions and performance such as a modulation system and a communication speed. Therefore, the communication functions and performance can be reset securely, and stable connection of a communication line can be maintained.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block configuration diagram showing main parts of a data communication apparatus according to a first embodiment of the present invention;
FIG. 2 is a block configuration diagram showing functions of a modem shown in FIG. 1 ;
FIG. 3 is a block configuration diagram of a mother-board shown in FIG. 1 ; and
FIG. 4 is a flowchart showing a modem processing routine according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention are explained in detail below with reference to the appended drawings.
FIG. 1 is a block configuration diagram showing main parts of a data communication apparatus according to a first embodiment of the present invention. A data communication apparatus 1 shown in FIG. 1 is a personal computer, for example. The personal computer 1 incorporates a modem 2 , and a mother board 100 that is connected to an input device such as a keyboard 3 , a mouse 4 , and a scanner and a light pen not shown. The data communication apparatus 1 is connected to another data communication apparatus via the modem 2 , and a communication line such as a telephone circuit, to thereby carry out communications. An interrupt request blocking section 20 is provided in the mother board 100 . The interrupt request blocking section 20 has a function of blocking the CPU provided in the mother board 100 of the data communication apparatus 1 from executing an interrupt processing having priority over retraining processing while the modem 2 is resetting communication functions and performance such as a modulation system and a communication speed.
FIG. 2 is a block configuration diagram showing functions of a modem shown in FIG. 1 . The modem 2 converts (modulates) digital data transmitted from a data communication apparatus into an analog audio signal, and sends the signal to a telephone circuit. The modem 2 also converts (demodulates) an analog audio signal transmitted through a telephone circuit into digital data. According to the recommendations (V series) of the International Telecommunication Union (ITU) concerning a modem, 33.6 kbps is a maximum communication speed of a vertical symmetric type for which a communication speed in the direction from a subscriber to a telephone office is the same as a communication speed in the direction from a telephone office to a subscriber. For a vertical asynchronous type of which communication speeds are different between both directions, a maximum communication speed is 33.6 kbps for an up direction, and 56 kbps for a down direction, respectively.
The modem 2 is always monitoring the quality of a telephone circuit. The modem 2 has a function of resetting a circuit speed, a protocol, an error correction, and a data compression system at any time when noise is mixed into the telephone circuit or when a reception level or an S/N ratio becomes low, to maintain the throughput and the line connection (This is prescribed in the recommendations of the ITU-T V.90 and the ITU-T V.34). A controller 22 reads the information of a line interface 21 to monitor the quality of the telephone circuit. Noise includes power source noise, noise of electromagnetic waves of a microwave oven, and noise of an inverter of an air conditioner. According to a modem currently available, software, that is, driver software that operates on the operating system, plays the main roles of the controller 22 and a modulator/demodulator 23 , based on the speeding up of the CPU provided on the data communication apparatus on which the modem is mounted. Therefore, this modem is called a software modem.
FIG. 3 is a block configuration diagram of the mother board shown in FIG. 1 . The mother board 100 that is incorporated in the data communication apparatus 1 is mounted with a CPU 100 , and various items that are connected to the CPU 10 via a bus line, including a modem chip 12 , a keyboard chip 13 , a mouse chip 14 , a video chip 15 , an audio chip 16 , a hard disk drive (HDD) 17 such as a magnetic disk and a magnetic optical disk as an external storage, a CD-ROM drive 18 , and a memory 19 such as a RAM as an internal storage. The CD-ROM drive 18 can be replaced by a DVD-ROM drive. The modem chip 12 , the keyboard chip 13 , the mouse chip 14 , the video chip 15 , and the audio chip 16 respectively have interface functions to take interface between the CPU 10 and the modem 2 , the keyboard 3 , the mouse 4 , a display not shown, and a speaker not shown, respectively in this order. The interrupt request blocking section 20 is provided on the mother board 100 . The CPU 10 carries out communication control processing to realize the software modem, and executes the operating system as other software, and various programs of a word processor, DVD reproduction, etc.
The interrupt request blocking section 20 has a relay 21 that is excited/non-excited by the modem chip 12 . Based on the excitation/non-excitation of the relay 21 , the bus line that connects the CPU 10 with the keyboard chip 13 and the mouse chip 14 that are connected to the input device (i.e., the keyboard 3 and the mouse 4 ) is blocked or the block is cancelled for a predetermined time. The relay 21 is usually in a non-excited state. When the input device is operated to prepare a new document, for example, the CPU 10 receives this instruction, and executes interrupt processing. This interrupt processing refers to making access to an application stored in the hard disk not shown via the HDD 17 to write into the memory 19 , or rewriting the screen of the display unit not shown by the video chip 15 , for example. The CPU 10 executes this processing with priority over the resetting processing carried out by the modem 2 .
A program for a modem processing routine that is used for the software modem is written into the memory 19 directly or via a recording medium. Alternatively, the program is downloaded from another computer connected via a communication line, and is written into the memory 19 . The program is then stored into the own hard disk. The CPU 10 executes the program by writing it into the memory 19 according to need.
FIG. 4 is a flowchart showing the modem processing routine according to the present invention. The driver software of the modem 2 executes this routine in a predetermined cycle.
At step 401 , the modem 2 monitors the quality of the telephone circuit. The controller 22 reads the information of the line interface 21 , and decides whether there is a request for resetting (retraining) communication functions and performance such as a modulation system and a communication speed. When it is decided that there is a request for resetting communication functions and performance, the process proceeds to step 402 . When it is decided that there is no request for resetting, the present routine is finished.
At step 402 , the modem 2 displays, on the screen of the display unit not shown, a message “the input device is invalid” that indicates that it is not possible to make the CPU 10 execute an interrupt processing with priority over the retraining processing. At the same time, the modem chip 12 excites the relay within the interrupt request blocking section 20 to open the relay contact. As a result, the bus line that connects the CPU 10 with the keyboard switch 13 and the mouse chip 14 connected to the input device (i.e., the keyboard 3 and the mouse 4 ) is blocked. Consequently, a signal input from the input device to the CPU 10 is blocked. With this arrangement, a user is persuaded not to carry out additional operation during the resetting. During the execution of the resetting, voice can be output as well as the message “the input device is invalid” is displayed on the screen. In other words, during the resetting, the sound volume of the modem is increased to inform the user of the data communication apparatus, by voice, that the communication functions and performance are being reset.
At step 403 , the resetting is started.
At step 404 , it is decided whether the resetting has ended. When it is decided that the resetting has ended, the process proceeds to step 405 . When it is decided that the resetting has not ended yet, the present routine is finished.
At step 405 , a message “the input device invalidation is cancelled” is displayed on the screen of the display unit to indicate that the CPU 10 can restart operation of executing an interrupt processing with priority over the retraining processing. At the same time, the modem chip 12 de-excites the relay within the interrupt request blocking section 20 to close the relay contact. As a result, the blocking of the bus line that connects the CPU 10 with the keyboard switch 13 and the mouse chip 14 connected to the input device (i.e., the keyboard 3 and the mouse 4 ) is cancelled. Consequently, a signal is normally input again from the input device to the CPU 10 .
At step 406 , it is decided whether a predetermined time has passed since the start of the execution of the processing at step 405 . When a predetermined time has passed, the process proceeds to step 407 . When a predetermined time has not passed, the present routine is finished. At step 407 , the message “the input device invalidation is cancelled” that is displayed on the screen of the display unit is cancelled.
During the resetting, the operation of the input device can be stored in the memory 19 of the CPU 10 . After the resetting, the operation stored in the memory 19 can be executed. | A data communication apparatus 1 has a processing section (CPU) 10 that executes at least a part of communication processing of a communication controller 2 and that executes processing other than the communication processing, wherein
The data communication apparatus 1 has an interrupt request blocking section 20 that blocks, during execution of a processing relevant to information exchange concerning a communication condition for the communication controller 2 to carry out a communication processing, an interrupt request to the processing section 10 with priority over the processing relevant to information exchange. With this arrangement, even when additional operation is carried out to execute an interrupt processing during execution of a processing concerning a communication condition such as a modulation system of a modem and a communication speed, the processing can be executed securely and a stable connection of a communication line can be maintained. | 6 |
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