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BACKGROUND OF THE INVENTION
The present invention relates to a method of duplex copying by use of an electrophotographic duplex copying machine capable of forming images on both sides of each transfer sheet.
In the conventional method of duplex copying, as illustrated in FIG. 1, a sheet original or a bound material, such as a book, is placed on a contact glass 1 and a photoconductive drum 3 is exposed to a light image of the original by the scanning of an exposure optical system 2 so that a latent electrostatic image corresponding to the light image is formed on the photoconductive drum 3. The thus formed latent electrostatic image is then developed by a development apparatus 4 and the developed image is transferred to one side of a transfer sheet fed from a transfer sheet feed apparatus 5. After the transferred image is fixed to the transfer sheet by an image fixing apparatus 6, the sheet is stacked on a secondary transfer sheet feed apparatus 7, with the image-bearing side up.
Another original is then placed on the contact glass 1, and taking the same procedure as in the above-mentioned case, a latent electrostatic image is formed on the photoconductive drum 3 by the scanning of the exposure optical system 2. The transfer sheet which has had an image fixed on one side thereof, and which has been stacked on the secondary transfer sheet feed apparatus 7, is then fed from the apparatus 7 in such a manner that the other side thereof is brought into contact with the photoconductive drum 3. Thus, a toner image corresponding to an image of the second original is transferred to the back side of the above-mentioned transfer sheet and is discharged to a transfer sheet output tray 8 with its second side up after the transferred image has been fixed by the image fixing apparatus 6.
Thus, in the conventional method of duplex copying, two copying processes are required for one duplex copying.
Even in the case where a duplex copying machine having an auto document feeder for use with sheet originals is utilized, the same copying process has to be repeated two times, as in the above case, for forming images on both sides of each transfer sheet. One copying process means, in this specification, a copying process consisting of formation of a latent electrostatic image on a photoconductive drum by one scanning and exposure, development of the latent electrostatic image, transfer of the developed image to a transfer sheet after fixing of the developed image, and discharging of the image-bearing transfer sheet.
Recently speed-up of duplex copying is greatly demanded and, accordingly, various attempts have been made to develop a high speed duplex copying machine. However, a satisfactory duplex copying machine capable of making duplex copies speedily has not been developed.
Moreover, in duplex copying, transfer sheets having had images farmed on one side thereof have to be transported again to an image transfer station for duplex copying. In this case, it is important that such transfer sheets are stacked neatly and in good order. Otherwise, copying of other sides of the transfer sheets cannot be performed in a proper position of the respective transfer sheets. However, in the conventional duplex copying machine, neat stacking or lineup of such transfer sheets is not made.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to provide a duplex copying method which permits speed-up of duplex copying.
Another object of the invention is to provide a duplex copying method which permits a speedy duplex copying by reducing the number of copying processes.
A further object of the invention is to provide a method of duplex copying which permits the making of duplex copies having images in the same image-bearing relationship as that of originals to be copied.
A further object of the present invention is to provide a method of duplex copying by use of a duplex copying machine with an auto document feeder capable of making duplex copies from originals having images on both sides.
A still further object of the invention is to provide a sheet feed apparatus capable of stacking sheets neatly and in good order, which is particularly suitable for use in a duplex copying machine.
According to a method of duplex copying of the present invention, by a single exposure scanning of two originals placed on a contact glass side by side in the scanning direction of exposure means and by feeding two transfer sheets in synchronism with the above process, the respective images of the two originals are formed separately on the respective two transfer sheets. Thus, unlike the above-mentioned conventional method, two copying processes are not required in one duplex copying, but one duplex copying process is finished by a single exposure scanning. Accordingly, the duplex copying speed is significantly improved.
Also, according to the method of duplex copying of the present invention, duplex copies having images in the same image-bearing relationship as that of originals to be copied are obtained by use of a swingable guide member which determines the discharging direction of the two originals.
According to another method of duplex copying by use of an auto document feeder, particularly in the case where duplex copies are made from originals having images on both sides, two of such originals are fed in succession to a slit exposure station and by using a copying procedure similar to that in the above-mentioned case, the speed-up of duplex copying is attained.
Furthermore, in the present invention, a sheet feed apparatus is provided, and comprises a front plate and a side reference plate, both being fixedly exposed normal to each other, at least one movable plate disposed parallel to either the front plate or the side reference plate, and a base for stacking transfer sheets thereon, whereby the transfer sheets are brought into contact with both the front plate and the side reference plate so that the transfer sheets in a stack are lined up neatly. This apparatus can be utilized as a sheet original feed apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention as well as other objects and further features thereof, reference is had to the following detailed description of the invention to be read in connection with the accompanying drawings, wherein:
FIG. 1 is a schematic sectional side elevation of a prior art duplex copying machine.
FIG. 2 is a schematic sectional side elevation of a duplex copying machine and an embodiment of a method of duplex copying according to the present invention by use of the duplex copying machine.
FIG. 3 illustrates how to place originals to be copied on a contact glass in the embodiment of a duplex copying method according to the present invention.
FIG. 4 illustrates an example of bound material to be copied according to the present invention.
FIG. 5 illustrates how to transport two transfer sheets in succession according to the present invention.
FIG. 6 is a sectional side elevation of an auto document feeder for use in the duplex copying method according to the present invention.
FIGS. 7 (a) and (b) illustrate a transporting method for transfer sheets when duplex copies are made from a bound material according to the present invention.
FIG. 8 is a schematic sectional side elevation of a transfer sheet feed apparatus for use in a method of duplex copying according to the present invention.
FIG. 9 is a partial schematic sectional side elevation of a sheet feed apparatus capable of stacking sheets neatly and in good order.
FIG. 10 is a schematic plan view of the sheet feed apparatus of FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 2 is a schematic sectional side elevation of a duplex copying machine that can be utilized in a duplex copying method according to the present invention. In the figure, reference numeral 9 designates a contact glass for placing an original document thereon, and reference numeral 10 represents an optical exposure system. The optical exposure system 10 comprises a first reflector 11 and a second reflector 12 which, respectively, move in the same direction parallel to the contact glass 9 with a speed ratio of 1:1/2, a stationary in-mirror lens 13 and a third reflector 14. Just for a convenience of illustrating the invention, a book is placed on the contact glass 9 in such a manner that its even page comes to a right half portion A (hereafter called side A) of the contact glass 9 and its odd page to a left half portion B (hereafter called side B) of the contact glass 9.
FIG. 3 is a schematic plan view of the contact glass 9 of FIG. 2 and illustrates how to place originals to be copied thereon according to the present invention. As mentioned above, the book is placed on the contact glass 9 in such a manner that an even page, for instance, page 10 falls on side A, and an odd page, for instance page 11, on side B as illustrated in FIG. 4.
In the case where a book to be copied is of A4 size (210×297 mm), the whole surface of the contact glass 9 is used in the present duplex copying machine, and in the case where a book to be copied is of B5 size (182×257 mm), the book is placed so that the two sides thereof coincide in position with an exposure starting line 9a and a lateral end line 9b of the contact glass 9 as illustrated in FIG. 3. It must be noted here that the transfer sheets have to be of the same size as the originals to be copied.
Alternatively, a book can be copied on the contact glass 9 by use of a center line 9c of the contact glass 9 as a reference line.
In the following example of a duplex copying method according to the present invention, an A4 size book is placed on the contact glass 9 for making duplex copies from pages 10 to 15 of the book.
First, an input of a program commanding a duplex copying from an A4 size book is applied to a control apparatus of a duplex copying machine for use with the present invention. In accordance with such an input signal received by the control apparatus, each copy element of the duplex copying apparatus is set from a one-side copy mode to a duplex copy mode by conventional techniques, and after a predetermined period of time, a display lamp is lighted, which indicates that the duplex copying machine is ready for such duplex copying.
A book to be copied is then placed in a predetermined position on the contact glass 9 and a duplex copying is started by closing a print switch, whereby an exposure lamp (not shown) comes on.
The first reflector 11 and the second reflector 12 are moved in the direction of the respective arrows thereof up to the respective positions indicated by long and two short dash lines, scanning page 10 on side A and page 11 on side B of the contact glass 9 so that the respective images are projected on a unformly charged photoconductive drum 16, thus latent electrostatic images corresponding to the images of pages 10 and 11 are formed on the photoconductive drum 16. The latent electrostatic images are developed by conventional techniques, such as by brush development by a development apparatus 17. After such exposure scanning, the first and second reflectors 11, 12 are returned to their respective original positions.
From a primary transfer sheet feed apparatus 18 for holding a supply of A4 size transfer sheets, two transfer sheets are transported in succession to an image transfer station with a predetermined interval therebetween by a sheet feed roller 19 and a pair of register rollers 20, the rotation of which is controlled by the above-mentioned control apparatus.
More specifically, referring to FIG. 5, transfer sheets P1, P2 are transported in the direction of an arrow indicated in the figure, with an interval t kept between the transfer sheets P1 and P2. The interval t is adjustable in accordance with the space between the respective originals placed on side A and side B. The interval will be discussed in more detail later.
The thus fed transfer sheets P1 and P2 are transported up to the image transfer station where they are brought into close contact with the photoconductive drum 16 successively and the above-mentioned developed images are electrostatically transferred from the photoconductive drum 16 to the transfer sheets P1 and P2 in succession by an image transfer apparatus 21 comprising an image transfer charger. Thus, an image of page 10 is transferred to the first side of the preceding transfer sheet P1 and that of page 11 to the first side of the succeeding transfer sheet P2. After such image transfer, the respective transfer sheets are fed into a thermal image fixing roller apparatus 22 where toner images on the respective transfer sheets are fixed thereto, and are then transferred to a quenching apparatus 23 where residual charges on the transfer sheets are made null. After this step, the preceding transfer sheet P1 is guided into a transfer sheet output tray 25 by a swingable transfer sheet guide member 24 which is initially switched to a position indicated by dash lines, and is then held between sheet output rollers 26 which are rotated faster than other sheet transfer rollers, and the transfer sheet P1 is discharged to the transfer sheet output tray 25. Since the sheet output rollers 26 are rotated faster than other sheet transfer rollers, the interval t between the preceding transfer sheet P1 and the succeeding transfer sheet P2 is lengthened, whereby it is made easier to feed the transfer sheet P2 into a secondary sheet feed apparatus 27 by the swingable transfer sheet guide 24.
Namely, immediately after it is detected by a switch SW1 that the leading edge of the transfer sheet P1 has passed through the swingable transfer sheet guide member 24, the swingable guide member 24 is switched to a position indicated by solid lines. Thus, even if the succeeding transfer sheet P2 is transferred with a comparatively short time lag, the switching of the direction of the transfer sheet P2 is easy.
The transfer sheet P2 is placed on the secondary sheet feed apparatus 27 with an image-bearing side (first page) up. At this time, a sheet feed roller 28 for use with the secondary sheet feed apparatus 27 is retracted to an appropriate position so as not to stand in the way of the transfer sheet P2. Alternatively, the secondary sheet feed apparatus 27 can be retracted so as to receive the transfer sheet P2 thereon.
The next page of the book is opened and placed on the contact glass 9 so that page 12 falls on side A and page 13 on side B. Thus, page 12 and page 13 are subjected to exposure scanning, thus latent electrostatic images corresponding to the images of pages 12 and 13 are formed on the photoconductive drum 16.
Meanwhile, the transfer sheet P2 is fed from the secondary sheet feed apparatus 27 by the sheet feed roller 28 and is transported to the image transfer station by the register rollers 20 which are rotated in synchronism with the rotation of the photoconductive drum 16. When the transfer sheet P2 has passed through a switch SW2, a transfer sheet P3 is fed from the primary transfer sheet feed apparatus 18 and is transported to the image transfer station at a predetermined interval t.
After the transfer sheet P2 has passed through the image transfer station 21 and the image fixing station 22, it is discharged to the transfer sheet output tray 25 with the first page down. On the other hand, the transfer sheet P3 is placed on the secondary sheet feed apparatus 27 with the first page up, after having passed through the image transfer station 21 and the image fixing station 22. Hereafter the same copying cycle is repeated.
When an image of page 15 of the book has been formed on the first page of a transfer sheet P4, the image-bearing transfer sheet P4 is directly discharged to the first transfer sheet output tray 25, without being transported into the second sheet feed apparatus 27.
When the above-mentioned copying steps have been finished, the transfer sheets P1 to P4 are stacked on the first transfer sheet output tray 25 in the same order of page as in the original book, each of which bears images in the same image bearing relationship as that of the respective pages of the original book. In other words, page 11 is on the front side of the transfer sheet P2 and page 12 is on the back side of the same, and page 13 and page 14 are on the front side and back side of the transfer sheet P3, respectively.
Referring to FIG. 4, when copying is started with an odd page of the book, the first odd page is placed on side A so that the odd page is copied on a transfer sheet. Alternatively, the first odd page is placed on side B and the sheet feed timing is set so as to feed a second transfer sheet without any preceding transfer sheet.
In the case where a duplex copying is made from a sheet original having images on both sides, reference is had to FIG. 6 which is a partial sectional side elevation of a duplex copying machine having an auto document feeder 29.
The auto document feeder 29 comprises a primary sheet original feed apparatus 30, a secondary sheet original feed apparatus 31 and a sheet original output tray 32 and is mounted on an exposure window 33 formed on an upper portion of the duplex copying machine.
Just for convenience of explanation of this duplex copying, it is supposed that two duplex sheet originals S1 and S2, i.e. two originals, each of which has images on both sides, are stacked on the primary sheet original feed apparatus 30 in order of page so that the first page of the originals faces down.
In explaining this duplex copying machine with the auto document feeder, the same reference numerals as in FIG. 2 are used for a photoconductive drum, other apparatuses arranged around the drum, and transfer sheet transport apparatuses.
The duplex originals S1, S2 stacked on the primary sheet original feed apparatus 30 are individually fed from the top original sheet by a sheet original feed roller 30a. In other words, the two original sheets are fed in order of S2 and S1 to the exposure window 33, where the original sheets are illuminated in order of page 3 and page 1 of the original sheets. Accordingly, latent electrostatic images are formed on the photoconductive drum 16 in the same order of the original sheets, and two transfer sheets P2, P1 are individually fed from the primary transfer sheet feed apparatus 18 at the same interval as that between the original sheets S1 and S2.
Thus, an image corresponding to that of page 3 of the sheet original S2 is formed on the first page (front page) of the preceding transfer sheet P2 and an image corresponding to that of page 1 of the sheet original S1 is formed on the first page (front page) of the succeeding transfer sheet P1 and the transfer sheets P2 and P1 are stacked on the secondary sheet feed apparatus 27 with the respective image-bearing sides (front pages) up in the order of P2 and P1.
Meanwhile, after illumination at the exposure window 33, the sheet originals S1, S2 are stacked on the secondary sheet original feed apparatus 31 in order of S2, S1 by a swingable sheet original guide member 34, with the respective odd pages up.
In a predetermined period of time after a switch SW3 detects that the two sheet originals have been transported to the secondary sheet original feed apparatus 31, a secondary sheet original feed roller 35 begins to be rotated so that the original sheets stacked on the secondary sheet original feed apparatus 31 are fed again from the top original sheet to the exposure window 33 in order of S1, S2. Thus, the respective latent electrostatic images are formed on the photoconductive drum 16 in order of page 2 and page 4 of the sheet originals.
Meanwhile, the transfer sheets P1, P2 are fed from the secondary sheet feed apparatus 27 in order of P1, P2, and on the second page of the preceding transfer sheet P1 is formed an image corresponding to that of page 2 of the sheet original S1, and on the second page of the succeeding transfer sheet P2 is formed an image corresponding to that of page 4 of the sheet original S2. The transfer sheets S1, S2 are then discharged to the transfer sheet output tray 25 with the respective odd pages down. Thus, they are stacked on the tray 25 in order of page.
The original sheets are also stacked on the sheet original output tray 32 in order of S1, S2 with the respective odd pages down. At this time, the swingable sheet original guide member 34 has been switched to a position indicated by dash lines.
The invention has been described in detail with particular reference to the case where duplex copying is made from two duplex originals, but it will be understood that in the case where duplex copying is made from three or more duplex originals, the same procedure as in the above case applies. Also, duplex copies can be made from originals having images only on one side thereof by the use of the swingable sheet original guide member 34.
Moreover, in the case where a number of copies are made from each original sheet, original sheets stacked on the sheet original output tray 32 in order of page are replaced to the primary sheet original feed apparatus 30 and copying is repeated a desired number of times. Alternatively, a copying cycle passing through the secondary sheet original feed apparatus 31, the exposure window 33, the swingable sheet original guide member 34 and back to the secondary sheet original feed apparatus 31 is repeated a desired number of times, whereby a duplex copying can be attained automatically.
It must be noted here that, if the original sheets are stacked on the primary sheet original feed apparatus 30 with odd pages thereof up, they cannot be stacked on the sheet original output tray 32 in order of page.
In general, when binding image-bearing transfer sheets in order of page, if there is not a sufficient binding margin in each transfer sheet, a disadvantage occurs that the image areas to be copied are also bound. In such a case, even if no interval is maintained, for example, between the transfer sheets P1 and P2 of FIG. 5 as shown in FIG. 7 (a), sometimes, binding margins thereof are still insufficient. In such case, as shown in FIG. 7 (b), the preceding transfer sheet P1 and the succeeding transfer sheet P2 are transported by overlapping each other by a length l so that a central portion l where no images are copied can be used as a binding margin. Moreover, according to the duplex copying method of the present invention, a binding margin is formed in an identical portion of each transfer sheet regardless of the image-bearing sides, i.e., the front side or back side of each transfer sheet. Thus, image areas are not bound.
FIG. 8 shows a transfer sheet feed apparatus for use with the present invention, capable of feeding two transfer sheets at a time, with the two sheets being overlapped partially.
In the figure, reference numeral 37 designates a cassette for holding a supply of transfer sheets. Reference numeral 38 denotes a sheet feed roller. Reference numeral 39 identifies a pair of sheet carriage rollers and reference numeral 40 represents sheet detection means.
The sheet carriage rollers 39 are always rotated at a speed of V and the sheet feed roller 38 has an over-running clutch (not shown) between the sheet feed roller 38 and a shaft 38a thereof.
A transfer sheet P1 fed by the sheet feed roller 38 is held between the sheet carriage rollers 39 and transported at the speed of V. When the transfer sheet P1 has reached the sheet carriage rollers 39, the sheet feed roller 38 is disconnected from a driving force, but it is rotated continuously by the over-running clutch. When the leading edge of the transfer sheet P1 is detected by sheet detection means 40, the sheet feed roller 38 is again driven and rotated.
Therefore, by adjusting the distance between the sheet detecting means 40 and the sheet feed roller 38, the overlapping length of each transfer sheet can be changed appropriately. The overlapping length can be changed easily in accordance with the size of a book to be copied or the size of a transfer sheet, for example, by connecting the sheet detecting means 40 with adjusting means, disposed outside the duplex copying machine, capable of adjusting the above-mentioned distance between the detecting means 40 and the sheet feed roller 38.
Alternatively, the sheet feed roller 38 is continuously rotated during one cycle of copying process without using the sheet detection means 40, so that the transfer sheets are individually transported, overlapping by the length from the front end of the cassette to the point at which the sheet feed roller 38 is in contact with the top sheet in the cassette.
As discussed previously, transfer sheets stacked on the secondary sheet feed apparatus are again transported in the direction of the image transfer station at the next step for duplex copying. In this case, the transfer sheets in the secondary sheet feed apparatus have to be stacked neatly and lined up. Otherwise, copying of the respective back sides of the transfer sheets cannot be performed in a proper position. The same requirement applies to sheet originals stacked on the sheet original feed apparatus.
FIGS. 9 and 10 show a sheet feed apparatus capable of stacking sheets neatly and in good order, which can be utilized as the secondary sheet feed apparatus and the sheet original feed apparatus.
In the figures, reference numerals 41, 42 represent a pair of delivery rollers. A transfer sheet S is held between the delivery rollers and delivered in the direction of an arrow a.
Reference numeral 49 identifies a base to place the transfer sheet S thereon. The base 49 is movable up and down by a driving mechanism (not shown). Reference numeral 50a designates an end plate disposed parallel to a front plate 43. The end plate 50a is supported by pins 51a, 52a so as to be slidable on a movable base 54a only in the directions of an arrow b.
Reference numeral 55a represents a motor which drives a cam 53a. The motor 55a is fixed to the movable base 54a. The cam 53a reciprocates the end plate 50a in the directions of the arrow b. The movable base 54a is movable on a frame (not shown) in the directions of the arrow b, guided by pins 57a. However, the movable base 54a is driven by a cam 59 and its position is also determined by the cam 59.
The cam 59 has step-shaped edges 61a, 62a, 63a, 61b, 62b, and 63b and can be rotated to three angular positions by a knob 60.
A roller 58a disposed on the movable base 54a is brought into contact with one of the cam edges 61a, 62a and 63a, whereby the position of the movable base 54a is determined.
The front plate 43 is for use in determining a reference position of one edge C of the transfer sheet S. A reference position of another edge D adjacent the edge C is determined by a side reference plate 48. The side reference plate 48 is fixed to the frame so as to be normal to the front plate 43. A movable side plate 50b is disposed so as to face and to be parallel to the side reference plate 48. The movable side plate 50b is also movable in the directions of an arrow c by a mechanism similar to that of the end plate 50a.
Reference numeral 44 represents discharging rollers which are rotated by a shaft 45 supported at one end of an L-shaped lever 46. The lever 46 rotates on a shaft 47.
The lever 46 is turned to a position indicated by solid lines by a solenoid 65.
Reference numeral 64 identifies a microswitch which detects the position of the turned lever 46 and which is actuated when pressed by the lever 46.
The illustrated sheet feed apparatus is operated as follows. The transfer sheet S having had an image on one side thereof is delivered by the rotation of the delivery rollers 41, 42 until it is brought into contact with the end plate 50a which is in a retracted position, so that it falls on the base 49. At this moment, since the magnetic plunger 65 is energized, the discharging rollers 44 are in an upper position indicated by solid lines so that the rollers 44 are not in the way of the transfer sheet S.
When the transfer sheet S has fallen on the base 49, the motors 55a, 55b are energized so that the cams 53a, 53b are rotated one time, respectively.
As a result, the end plate 50a and the movable side plate 50b are reciprocated one time in the respective directions of the arrow b and the arrow c.
By this movement of the end plate 50a, the edge C of the transfer sheet S is brought into contact with the front plate 43, and by the movement of the movable side plate 50b, the edge D of the transfer sheet S is brought into contact with the side reference plate 48. Thus, the transfer sheet S is placed in a predetermined reference position.
In the same manner, transfer sheets S having had images on one side thereof, which are delivered in succession by the delivery rollers 41, 42, are stacked on the base 49, with their respective edges C, D neatly lined up. Thus, a space surrounded by the base 49, the front plate 43, the side reference plate 48, end plate 50a and the movable side plate 50b is used as a tray for holding transfer sheets S having had images on one side thereof.
When one-side copying of a certain set of transfer sheets has been finished, since the magnetic plunger 65 is disconnected from a power source, the lever 46 is turned to a position indicated by long and short dash lines, and the discharging rollers 44 are moved downwards. At the same time, the microswitch 64 is pressed and turned on. With the microswitch 64 on, the base 49 is moved upwards by a driving mechanism (not shown). Accordingly, a stack of transfer sheets S on the base 49 is also moved upwards. As a result, the discharging rollers 44 are pressed upwards by the stack of transfer sheets S, and the lever 46 is turned slightly in the direction of a position indicated by solid lines so that the lever 46 is disengaged from the microswitch 64. Thus, the microswitch 64 is turned off and the upward movement of the base 49 is terminated. At this stage, the top layer of the stack of transfer sheets S is located in a reference position indicated by long and dash line.
Thus, when the rotation of the discharging rollers 44 is started, since the rotating direction of the delivery rollers 41, 42 has been switched in the reverse direction, the transfer sheets are individually discharged in the direction opposite to that of the arrow a for duplex copying.
There is no particular restriction with respect to the operational timing of the end plate 50a and the movable side plate 50b. However, it is preferable that they are moved at the same time. For an accurate discharging of transfer sheets, it is also preferable that the end plate 50a and the movable side plate 50b are in contact with the edges E and F of the transfer sheets, respectively, when they are discharged.
When the sheet size is changed, the cam 59 is rotated to a proper position by turning the knob 60, whereby the movable bases 54a, 54b are moved to a suitable position, respectively, for a sheet size to be set, and the end plate 50a and the movable side plate 50b are reciprocated in the respective directions of the arrow b and the arrow c from the respective reference positions thereof.
By disposing the base 49 and the front plate 43 slantingly, the edge C of the transfer sheets S comes in contact with the front plate 43 under the weight of the transfer sheets S. In this case, the end plate 50a can be disposed fixedly.
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In the method, two originals are placed side-by-side on the contact glass of an electrophotographic duplex copying machine and are scanned successively, in a single scanning operation, by the exposure optical system of the machine to form respective successive images on a photoconductive drum rotated past an image transfer device. Two transfer sheets are fed successively, with a short interval therebetween, from a primary supply device for transfer sheets, past the image transfer device in synchronism with the image formation on the drum, to provide duplex copies, having images in the same relation as that of the two originals, in a single copying cycle or process. By utilizing a secondary sheet supply device and a suitable switching device, images can be provided on both sides or surfaces of a transfer sheet or sheets. The duplex copying apparatus includes a novel sheet feed device effective to stack transfer sheets neatly.
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BACKGROUND AND SUMMARY OF THE INVENTION
The present invention has reference to bleaching, especially with chlorine, of cellulose pulp obtained by delignification of vegetable fiber containing raw material such as wood, bamboo, bagasse, straw, and reeds.
Conventionally, such chlorine bleaching is performed at a pulp concentration of about 3-4 percent fibers or solids, i.e. at relatively low concentration of fibers in a watery suspension. This concentration has by experience been found most suitable, since chlorine has a very rapid initial reaction with pulp, whereby the main part of the chlorine reacts directly after the introduction. During such bleaching there is a risk that certain parts of the pulp are overchlorinated and other parts underchlorinated, but due to a relatively large water quantity an effective "mixing-in" and a relatively even bleaching result are possible. Chlorine can be added as gas or as gas dissolved in liquid, so called chlorine water.
As a process it is also known to bleach pulp with chlorine at higher concentrations, e.g. 10 percent, which generally speaking is common in treatment stages in modern bleach plants. If chlorine gas is to be mixed into pulp of 10 percent concentration, there are problems associated with proper mixing-in of the gas. If, on the other hand, the chlorine is to be added as chlorine water, the liquid quantity will be relatively large with the normal solubility of chlorine in water, and the pulp will be diluted to a concentration far below the desired 10 percent concentration.
According to the present invention it is possible by using chlorine water to bleach pulp at about 10 percent solids concentration. It has been found that the liquid quantity which is necessary in order to dilute pulp of about 30-40 percent solids concentration to about 10 percent solids concentration corresponds to the amount of liquid which contains a normal chlorine charge therein for bleaching unbleached sulphate pulp or the like. According to the present invention, pulp is dewatered by conventional dewatering apparatus, such as certain types of presses, to obtain a solids concentration of 30-40 percent. The concentrated pulp is then treated in a vessel with a first treatment liquid having between 3 and 10 grams of chlorine gas dissolved therein, corresponding to a charge of 20 to 80 kilograms of chlorine per ton of pulp, a normal chlorine charge treatment. The solids concentration of the pulp after treatment is then 6-15 percent, preferably about 10 percent.
According to another aspect of the present invention the pulp is first treated with a certain quantity of C10 2 dissolved in liquid, preferably with a quantity corresponding to 2-8 kgs per ton pulp calculated as active chlorine, preferably in the same treatment vessel. The treated pulp may be transported to a retention vessel and retained therein for a predetermined period of time in order to reduce the amount of residual chlorine in the pulp for further stages of treatment thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a mill pulp line assembly from the digester stage to the treatment stage according to the present invention; and
FIG. 2 is a schematic diagram of the mill pulp line assembly shown in FIG. 1 with the addition of an oxygen bleaching pretreatment stage.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, A signifies fiber containing raw material which is continuously fed into the digester 1. The fiber material may be washed in the digester 1 before it is fed to a second washing stage 2, which may comprise a continuous diffuser. After washing the pulp is transported to the screening department 3 and thereafter to the thickener 6 and from there to the storage container 7. From the storage container 7 the pulp is pumped to the thickening device 8, which can be a press and which in addition to pressing even can function to wash the pulp before the pulp goes further along its path of movement on to the chlorinator 9, wherein chlorine dioxide from line 12 may be added from the top of chlorinator 9 and mixed by a device 10, while a chlorine solution from line 13 is added into the bottom part in or close to a mixing device 11. The pump 14 transports the pulp to an upflow reaction tower 15 having a top with a built-in continuous washing diffuser. Chemicals, e.g. NaOH, for the next bleaching stage may be added to the pulp through the pipe 17 and warm water may be added through the pipe 18. The dirty water from the washing or the so-called back-water from the chlorine treatment leaves at 19 and the pulp at B.
If desired, the chlorinated pulp may be transported to a retention vessel, shown diagrammatically at 20 in FIG. 1 of the drawings, for retention therein for a predetermined period of time in order to reduce the amount of residual chlorine in the pulp for further stages of treatment thereof.
After retention, the pulp may be washed, without any considerable dilution thereof.
The FIG. 2 assembly has reference numbers corresponding to the FIG. 1 assembly and additionally includes a thickening device 4, e.g. a press or a decker for thickening to high concentration before possible oxygen gas treatment, which takes place in a container 5.
If a sequence according to the invention is followed, the concentration of the pulp in the reaction container 15 will be about 10 percent. When conventional 3-4 percent solids concentration pulp is employed a continuous diffuser which is installed in the top of the container 15 must first thicken the pulp from the 3-4 percent concentration up to about 10 percent solids before the pulp can be washed, which necessitates extra apparatus, for example extra screen rings which considerably complicate and make the equipment more expensive. The washing itself in such a diffuser, which can be of a type disclosed in U.S. Pat. No. 3,372,087 for example, works according to the displacement principle. Compared to conventional chlorine treatment at 3-4 percent concentration the 10 percent pulp contains considerably less liquid which is to be displaced, whereby the invention has the great advantage that the displaced liquid quantity 19 will be considerably smaller. Since dirty water or back water from the chlorination stage is considered one of the major sources of pollution from such facilities, and must be treated in various manners in the factories, such treatment is considerably facilitated if the quantity of back water is considerably less, as it is according to the present invention.
If the same reaction time is provided for the pulp after the addition of the chlorine as when bleaching conventionally, it is possible with bleaching of 10 percent pulp to reduce the volume of the reaction container 15 correspondingly. Another advantage according to the present invention is that a bleach tower of smaller size may be used than at conventional chlorine bleaching facilities, which means reduced buying, installation, and maintenance costs.
The necessary chemical quantity needed for the treatment of pulp is dependent upon the type of pulp, and in order to illustrate the charges which can come into question the below figures can serve as an example. The chlorine is given in kilograms per ton of pulp and the chlorine dioxide is expressed as active chlorine in kilograms per tone of pulp.
______________________________________ ClO.sub.2 Cl.sub.2Unbleached pulp, pine sulphate, 5 60Kappa number 33Semibleached pulp (e.g. oxygen 4 40bleached), pine sulphate,Kappa number 16Unbleached pulp, deciduous 5 47sulphate, Kappa number 22Semibleached pulp (e.g. oxygen 3 30bleached), deciduous sulphate,Kappa number 10______________________________________
In all the above exemplified cases it is possible by using different degrees of solubility of chlorine in water to obtain a total solution quantity which is to be added to the pulp of about 8000 liters per ton of pulp. If starting with 40 percent as a suitable concentration of the pulp before the treatment the final concentration will be as follows: 40 percent pulp contains 1.5 tons of water per tone of pulp and with an addition of 8000 liters, or in other words about 8 tons, the total liquid quantity in the pulp will be 1.5 + 8.0 = 9.5 tons per ton of pulp, which corresponds to a pulp solids concentration of about 9.5 percent. If for certain reasons it is desirable to use smaller solution quantities, it may be necessary to use special methods to obtain the solution of the same chlorine quantities in the liquid, e.g. by using other pressure-temperature conditions respectively.
Thickening of pulp to 30-40 percent can be effected by dewatering it in apparatus designed for such a purpose such as a screw press or drum press, vacuum apparatus, centrifugal apparatus or similar apparatus, with or without simultaneous treatment means such as washing means. Washing may be done in a "wash press."
For effecting mixing of suitable chemical solutions into the pulp in the container 9, a mixer of known type can be used, whereby the solution can be pumped into the pulp close to a rotating mixing body equipped with wings, pins or similar structures, or the solution can also be more or less added into the pulp itself through one or more outlets moving in the pulp, whereby possibly the very best distribution in the relatively thick pulp will be obtained. The last mentioned moveable outlet may be supported by added stirring devices or other mixing devices. The container 9 should suitably be filled with pulp suspension.
The invention has been herein described in what is presently conceived to be the most practical and preferred embodiment, however, many variations may be made thereof within the scope of the invention, which scope is not to be limited except by the appended claims.
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A method for bleaching pulp comprising the steps of dewatering or thickening the pulp to a solids concentration of about 30-40 percent, and then treating the pulp with a first treatment liquid, in a vessel, having between 3 and 10 grams of chlorine gas dissolved therein, corresponding to a charge of 20-80 kg of chlorine per ton of pulp resulting in a solids concentration of the treated pulp of 6-15 percent. Treatment with a second liquid in the vessel and other treatment steps may also be performed.
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BACKGROUND OF THE INVENTION
1. Technical Field
This invention relates to earth boring equipment. More particularly, this invention relates to an auger bit extension length. Specifically, this invention relates to a novel earthen auger length having a reinforced boring flight at the front end, as well as a reinforced boring flight and soil deflector at the back end.
2. Background Information
Earthen auger bits are used to bore holes in soil for the emplacement of fence posts, telephone poles, and the like. An earthen auger bit is used with a power mechanism for overall lateral movement to drive the bit into the soil. The power mechanism is also used for axial movement in rotating the bit. From forward movement, as well as axial spinning of the auger blade, the bit penetrates deeper into the soil and rock.
Resembling a corkscrew, the bit has six parts: screw, spurs, cutting edges, flight, shaft, and tang. The screw, also called a pilot point, is long and smaller than the flight in diameter; it centers the bit and draws it into the earth. At the working end of the flight there may be sharp points called spurs, which score a circle equal in diameter to the hole, and radial cutting edges that cut material within the scored circle. The flight is helical and the rotation and outward spiraling of the flight results in soil moving back out of the hole along the spiral. The shaft extends along the entire inner diameter of the bit, beginning with the tang and ending with the tip of the screw. The tang can be any shape, but usually square or hexagonal, and fits in either the chuck on the power mechanism, or another auger length used for extending the length of the bore hole. Additional auger lengths are added as the cutting head of the auger penetrates deeper into the earth. The size of the auger length depends on the pitch, thickness, and length of the desired hole.
A general auger length can be separated in two parts: a bit, comprising the screw, spur, cutting edges and tang, can be separate from the lengths, comprising the flight, shaft and tang. This enables each length to be interchangeable. The first end of each length comprises a tang receiving hole and the second end of each length comprises a tang. In this method, lengths can be “stacked” on each other as more drilling depth is required, as the first length receives the tang into the tang receiving hole.
BRIEF SUMMARY OF THE INVENTION
In general, the earth auger of the present invention is defined as comprising a pilot point and cutting edges on an auger bit, and a flight, shaft, tang, reinforcement braces and a deflector on an auger length. As the auger penetrates the earth, the flight rotates axially driving the auger deeper and pulling the soil out of the bore hole through the helical rotation of the flight. The leading flight blade undergoes tremendous torque and compressive forces from penetrating the earth and breaking up the soil or rock.
The present invention reinforces the lead flight blade by applying a flight brace proximate to the front end of the auger length. This brace adds to the strength of the lead flight and reduces stress and fatigue on the auger length. A flight brace is also added to the last flight blade, thus strengthening the connection area where two lengths are combined and require the most torque reinforcement due to a break in the overall shaft of the auger. This also helps to stabilize the shafts when stacked together and held by the tang and tang receiving hole. A deflection mechanism is also applied to the last flight and proximate the back end of the auger length. The deflector is used to move rock and soil outwardly from the shaft such that it is collected by the next flight blade and prevents soil from contacting the front flight brace of the subsequent auger length. This adds to the overall stability and reinforcement of the first auger flight blade.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
A preferred embodiment of the invention, illustrated of the best mode in which Applicant contemplates applying the principles, is set forth in the following description and is shown in the drawings and is particularly and distinctly pointed out and set forth in the appended claims.
FIG. 1 is a side profile of a mechanically powered earth auger of the present invention with part of the drilling tube cut-away;
FIG. 2 is a side profile view of the reinforced earth auger length of the present invention;
FIG. 3 is a side profile view the reinforced earth auger length of FIG. 2 ;
FIG. 4 is back profile view of the reinforced auger length of FIG. 3 , taken along line 4 - 4 in FIG. 3 ;
FIG. 5 is a front profile view of the reinforced auger length of FIG. 3 , taken along line 5 - 5 in FIG. 3 ;
FIG. 6 is a side profile view of the back end of the reinforced auger length of FIG. 3 , with portions cut away and part of the coupler shown in phantom;
FIG. 7 is a side profile view of the back end of the reinforced auger length of FIG. 3 , with portions cut away;
FIG. 8 is a side profile view of the back end of the reinforced auger big of FIG. 7 , taken from the opposite side with parts cut away;
FIG. 9 is a side profile view of two auger length lengths coupled together, with the coupler shown in phantom, and parts cut away;
FIG. 10 is a profile view of the two auger coupling of FIG. 9 .
Similar numbers refer to similar parts throughout the drawings.
DETAILED DESCRIPTION OF THE INVENTION
The reinforced earth auger length of the present invention is indicated generally at 1 in FIGS. 1 and 2 as an element of an earthen auger machine 3 . Machine 3 is typically disposed in a pit 8 formed in the earth's soil or ground 6 and configured to bore a hole through ground 6 for the purpose of laying underground pipe in the bored hole. Machine 3 typically bores a hole from within a pit such as pit 8 to another pit which may be spaced several hundred feet away. Machine 3 includes an engine compartment 2 housing an engine (not shown) which powers the forward and axial momentum of a rotational output shaft 5 for rotationally driving the auger length 1 . A tube 4 surrounds the plurality of auger lengths 1 stacked together longitudinally for extending into the hole formed in ground 6 and terminates with cutting head 18 attached at the end of the outermost auger length 1 .
Reinforced auger length 1 of the present invention is comprised of a shaft 10 , a flight 14 , a back end 20 , a front end 22 , a back flight brace 32 , a front flight brace 42 , and a deflector 52 . Back end 20 and front end 22 are located at opposite longitudinal ends of auger length 1 and spaced apart. Shaft 10 is generally cylindrical and runs the entire length of auger length 1 and transfers rotational torque to flight 14 from rotational output shaft 5 . Flight 14 is helical and begins at edge 47 at front end 22 and spirally encircles shaft 10 , terminating at edge 37 at back end 20 . Flight 14 includes an inner edge 15 adjacent to shaft 10 along the length of shaft 10 . Flight 14 also includes an outer edge 16 , spaced apart and opposite from inner edge 15 . Front flight brace 42 is proximate front end 22 . Back flight brace 32 and deflector 52 are proximate back end 20 .
Back flight brace 32 is herein described in greater detail. Shown in FIG. 4 , brace 32 is generally a box structure of steel or other strong metal, but may be a solid block of metal if desired. Brace 32 is proximate terminating edge 37 at back end 20 of auger length 1 and shaft 10 . Back flight brace 32 includes a first end 33 , a second end 34 , an adjacent side 35 , a distal side 36 , and a top panel 38 . First end 33 is proximate shaft 10 , with a portion adjacent to shaft 10 and welded thereto. Shown in FIG. 7 , first end 33 is generally flush with the outer end of shaft 10 , extending along the length of shaft 10 and terminating at flight 14 . Shown in FIG. 4 and 7 , second end 34 is spaced apart from first end 33 and is generally proximate outer edge 16 of flight 14 . Adjacent side 35 is adjacent to terminating edge 37 of flight 14 , welded thereto in a generally straight weld parallel to terminating edge 37 . Distal side 36 is spaced apart from side 35 and extends from first end 33 of back flight brace 32 to second end 34 . One edge of side 36 is welded to flight 14 and complementary shaped to follow the helix of flight 14 from first end 33 to second end 34 .
Outwardly extending ends 33 and 34 , and outwardly extending sides 35 and 36 are welded together to form a box shape. The box bottom is formed from welding the box structure onto flight 14 . The box top is formed from top panel 38 welded onto the extending and outer most edges of 33 , 34 , 35 , and 36 . In this way, a reinforcing box is formed on the rearmost flight blade to solidify flight 14 against rotational torque and compressive stress.
Front flight brace 42 is herein described in greater detail. Shown in FIG. 5 front flight brace 42 is substantially similar to back flight brace 32 . Front flight brace 42 is generally a box structure of steel or other strong metal, but may be a solid block of metal if desired. Brace 42 is proximate edge 47 at front end 22 of auger length 1 and shaft 10 , and includes a first end 43 , a second end 44 , an adjacent side 45 , a distal side 46 , and a top panel 48 . Ends 43 and 44 , and sides 45 and 46 are substantially similar to ends 33 and 34 , and sides 35 and 36 and operate similarly on flight 14 .
Substantially similar to back flight brace 32 , front flight brace 42 is a box structure formed from welding together ends 43 and 44 , and sides 45 and 46 . The box bottom is formed from welding the box structure onto flight 14 . The box top is formed from top panel 48 welded onto the extending and outer most edges of 43 , 44 , 45 , and 46 . In this way, a reinforcing box is formed on the rearmost flight blade to solidify flight 14 against rotational torque and compressive stress.
Deflector 52 is herein described in greater detail. Shown in FIG. 4 , 6 , and 8 , deflector 52 is generally a solid and flat block of steel or other strong metal. Deflector 52 is proximate edge 37 at back end 20 of auger length 1 and shaft 10 , and includes a first end 53 , a second end 54 , an adjacent side 55 , and a distal side 56 . Similarly to front flight brace 42 and back flight brace 32 , first end 53 is proximate shaft 10 , with a portion adjacent to shaft 10 and welded thereto. Second end 54 is spaced apart from first end 53 and is generally proximate outer edge 16 of flight 14 . Adjacent side 55 is adjacent to terminating edge 37 of flight 14 , welded thereto in a generally straight weld parallel to terminating edge 37 . Shown in FIG. 4 , adjacent side 55 is adjacent to terminating edge 37 on the opposite side from back flight brace 32 . Distal side 56 is spaced apart from adjacent side 55 and distal to terminating edge 37 .
Auger lengths 1 of the present invention can be joined and securely held together by any general securing mechanism. The preferred method of securing two lengths 1 is shown in FIGS. 4 and 5 . Shaft 10 of each length 1 includes a hexagonal joint hole 27 recessed longitudinally into shaft 10 at front 22 and back 20 end. Joint hole 27 receives approximately one half the length of a coupler 24 . Coupler 24 includes two pin holes 25 and six flat sides 29 which are spaced to form a complementing hexagonal insert for joint hole 27 . Pin holes 25 are spaced apart and parallel to one another, and extend from the center of side 29 of coupler 24 through and out the opposite and parallel side 29 . Pin holes 25 are complementary aligned with a pin hole 26 in shaft 10 , extending through joint hole 27 on each end 20 and 22 of auger length 1 . Pin holes 25 and 26 receive a pin 28 .
Shown in FIG. 9 in phantom, as a means for securing two auger lengths 1 , coupler 24 is inserted into joint hole 27 . Joint hole 27 receives approximately one half the length of coupler 24 , the protruding one half being inserted into second length 1 . Pin 28 is inserted into pin hole 26 in shaft 10 and extended through pin hole 25 in coupler 24 . The length of pin 28 allows it to pass entirely through coupler 24 and out pin holes 25 and 26 on the distal side of coupler 24 and shaft 10 . Pin 28 is then secured with a nut 30 , which tightly holds pin 28 and prevents its removal. Shown in FIG. 9 in phantom, each end of coupler 24 is inserted into a length 1 and secured through pin holes 25 and 26 to each length 1 by pins 28 . Shown in FIG. 1 , to facilitate drilling, cutting head 18 is attached to the first length 1 using coupler 24 in same manner as adding another length 1 .
In the preferred method of operation, cutting head 18 is attached to front end 22 of length 1 . Back end 20 of length 1 is attached to machine 3 at rotational output shaft 5 . Machine 3 provides lateral movement as well as rotational movement to drive cutting head 18 into the soil. As rotational movement is transferred from output shaft 5 to shaft 10 , flight 14 rotates axially around shaft 10 , bringing soil outward from inside the bore hole due to the helical structure of flight 14 .
As machine 3 moves length 1 and cutting head 18 farther into the soil, a maximum distance is eventually reached. If the desired bore hole depth has not yet been achieved, an additional length 1 is added. This is accomplished by manually disconnecting back end 20 of length 1 a from output shaft 5 , and connecting back end 20 of length 1 b to output shaft 5 . Back end 20 of length 1 a is then connected to front end 22 of output shaft 1 b , and the overall length of the structure is increased by the size of length 1 b . Machine 3 is shown in FIG. 1 with auger lengths 1 a and 1 b coupled to extend the depth bore hole. The means for attaching lengths 1 is coupler 24 , which is inserted into joint hole 27 in back end 20 of length 1 a , as well as joint hole 27 in front end 22 of length 1 b . Coupler 24 is secured by way of pins 28 extending through shaft 10 of each length 1 a and 1 b , and pin holes 25 and 26 . Pins 28 are secured by nuts 30 , which prevent pins 28 from being dislodged without removing nut 30 .
As overall length of the structure is increased by adding more lengths 1 , the linear structure of shaft 10 and stability of auger machine 3 is maintained by rear flight brace 32 and front flight brace 42 . Braces 32 and 42 reinforce terminating edges 37 and 47 of flight 14 , respectively, in each length 1 . As flight 14 turns, terminating edges 37 and 47 are located at the transfer point where rotational power from one length 1 is transferred to the next length 1 . This break in the overall longitudinal structure allows rotational torque to stress the trailing and leading terminating edges 37 and 47 . Stress at edges 37 and 47 could lead to shearing or bending of flight 14 , changing the helical shape and disrupting the flow of soil outward from the bore hole.
Deflector 52 is located at back end 20 of length 1 at terminating edge 37 of flight 14 . As soil passes along flight 14 , deflector 52 directs soil outward from terminating edge 37 and prevents soil from contacting front flight brace 42 of the subsequent length 1 . This adds to the stability of length 1 by directing soil away from the leading edge 47 of length 1 .
In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.
Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described.
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A brace or gusset is added to the first and last flight blade of an auger length for stability and reinforcement. The braces are generally box shaped with the flight blade as the box bottom. The brace walls are welded together along with a top panel. The brace is adjacent the auger shaft on one end and complementary shaped on one side to conform to the shape of the flight helix. A deflector is added to the last flight blade to distribute dirt and debris away from the first flight blade on the subsequent auger length. The auger length is reinforced against the twisting torque and compressive forces that occur at the first and last flight blade.
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BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a copying apparatus or an electronic printer for forming an image on a recording medium and, more particularly, to an image forming apparatus with a stacking apparatus for stacking an exhausted recording medium with images thereon.
In a conventional copying apparatus, as shown in FIG. 1, a sheet P is supplied from a paper cassette 1 to an image forming section, and an image is transferred to the sheet P. The sheet P is then discharged from an discharge port 2 and stacked on a tray 3.
The sheet P is discharged on the tray 3 such that an image formation surface P' of the sheet P faces upward so as to allow an operator to see the formed image.
When the discharged sheets P are stacked on the tray 3 while the image formation surfaces P' thereof face upward, the order of sheets P is reversed at the end of the copying operation. In other words, the uppermost image corresponds to the last document image. In order to rearrange the sheets P in the same order as that of the document images, the stacked sheets P must be reversed in order again, resulting in a cumbersome operation.
In addition, when each of a plurality of documents is to be copied a plurality of times, a plurality of copied sheets are stacked on the tray 3 in units of documents. In this case, the boundary between a plurality of copied sheets for a given document and those for a document next to the given document cannot be easily identified. For this reason, a sorting/stacking apparatus called a sorter is proposed. When a copying apparatus has a sorter, the overall size is increased at high cost.
SUMMARY OF THE INVENTION
The present invention has been made in consideration of the above situation, and has as its object to provide a recording apparatus with a stacking apparatus, wherein storing of the copied sheets discharged on a discharge tray can be automatically performed with a simple arrangement.
According to one aspect of the present invention, there is provided a recording apparatus which records information on a sheet-like recording medium having a first surface and a second surface opposing the first surface, comprising recording means for recording the information on the first surface while the first surface of the recording medium faces upward, conveying means for conveying the recording medium having the information recorded by said recording means along a first convey path while the first surface faces upward, switching means arranged to oppose a distal end of the first convey path and movable between a first position where the recording medium conveyed along the first convey path is guided in a second convey path and a second position where the recording medium is guided in a third convey path, a temporary stacking tray, arranged to oppose a distal end of the second convey path, for temporarily stacking the recording medium guided by said switching means from the first convey path to the second convey path while the first surface faces upward, said temporary stacking tray having a temporary stacking surface which is closed to the external atmosphere, a stacking tray, arranged at a distal end of the third convey path, for stacking the recording medium guided along the third convey path, said stacking tray having a stacking surface open to the external atmosphere, and inverting means for conveying the recording medium temporarily stacked on said temporary stacking tray to the third convey path through a fourth convey path without passing through said switching means while the second surface faces upward.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view showing a conventional copying apparatus; and
FIGS. 2 to 9 show a recording apparatus according to an embodiment of the present invention, in which
FIG. 2 is a side view of a copying apparatus as the recording apparatus,
FIG. 3 is a side view schematically showing an inversion mechanism of a stacking apparatus attached to the copying apparatus,
FIG. 4 is a partial cutaway front view of a variable mechanism of the stacking apparatus,
FIG. 5 is a side sectional view of the variable mechanism,
FIG. 6 is a side view showing a drive system for the inversion and variable mechanisms,
FIG. 7 is a block diagram of a control system of the stacking apparatus,
FIGS. 8A to 8C are respectively side views schematically showing the inversion operation, and
FIG. 9 is a side view schematically showing the noninversion operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A recording apparatus according to an embodiment of the present invention will be described in detail with reference to FIGS. 2 to 9 wherein the present invention is applied to a copying apparatus.
Referring to FIG. 2, reference numeral 11 denotes the housing of an electronic copying apparatus. A document table 12 is arranged at the upper portion of the housing 11. A paper cassette 13 is detachably mounted on a lower portion of one side wall of the housing 11 to feed sheets P as a recording medium. A stacking apparatus 15 is detachably mounted on the other side wall of the housing 11 to stack the discharged sheets P, as shown in FIG. 3. An image forming section 14 is formed in the housing 11 although detail of the section 14 is not illustrated. The image formation section 14 comprises: a photosensitive drum 14a; a charger 14b, an exposure unit 14c, a developing unit 14d, a transfer unit 14e, a separation unit 14f and a cleaning unit 14g which are arranged to surround the drum 14a; a fixing unit 14h for fixing a toner image transferred by the transfer unit 14e to the sheet P; and a convey unit 14i for picking up the sheet P from the cassette 13 and conveying the sheet P to the stacking apparatus 15 through the units 14e and 14h. Thereafter, an image is transferred from the drum 14a to the sheet P supplied from the cassette 13, and the sheet P is then conveyed in the stacking apparatus 15.
The stacking apparatus 15 has the arrangement shown in FIGS. 3 to 6. The apparatus 15 has a port 15a communicating with a discharge port lla of the housing 11. The apparatus 15 also has first to third convey paths 16, 17 and 19. The proximal end portions of the paths 16 and 17 are located near the port 15a and are selectively closed by a flip lever 18. The lever 18 can be actuated by a flip lever solenoid 78, as shown in FIG. 7. The paths 16 and 17 are coupled to each other through the path 19.
A pair of exhaust rollers 20 are on the end portion of the path 16. A discharged sheet detection switch 21 is set on the feed side of the rollers 20. A full detection switch 22 is set on the delivery side of the rollers 20. A convey roller 23 with a plurality of meshing grooves 23a thereon is arranged at the end portion of the path 17. A first bracing roller 24 is in rolling contact with the lower portion of the roller 23. Similarly, a second bracing roller 25 is in rolling contact with the upper portion of the roller 23. An inversion detection switch 67 is arranged at the feed side of the roller 23. An inversion plate 26 is pivotally mounted about a pivot pin 26a at the delivery side of the roller 23 so as to constitute an inversion mechanism A. An inversion plate roller 27 is integrally mounted at the pivotal end of the plate 26. The plate 26 is actuated by an inversion solenoid 28 to be brought into contact with or separated from the roller 25.
A discharge path 41 is formed in the housing 11 so as to deliver the sheet P with a fixed image to the stacking apparatus 15. A pair of feed rollers 42, an outlet switch 43 and a pair of discharge rollers 44 are arranged sequentially along the sheet feed direction of the path 41. The rollers 44 oppose the port 11a.
The apparatus 15 has a discharge tray 29 for receiving the sheet P discharged from the path 16. The tray 29 extends obliquely upward from the housing 11. A vertical portion 29a is integrally formed with the front end portion of the tray 29. A subtray 30 is arranged below the tray 29 to be parallel therewith.
As shown in FIG. 4, the tray 29 is placed on an upper surface of a slider 31 which constitutes a variable mechanism B. A pair of engaging recesses 32 are formed in the upper surface of the slider 31. A pair of projections 33 extending from the bottom surface of the tray 29 can be engaged with the recesses 32, respectively. In other words, the tray 29 can be detachably mounted on the slider 31. Two sides of the slider 31 are supported by a frame 36 through pivot links 34 and brackets 35. One end of a connecting rod 37 is connected to one of the links 34 through a link pin 34a. A half-rotatable spring clutch 39 is connected to the other end of the rod 37 through a crank pin 38. The pins 34a and 38 and the rod 37 constitute a crank mechanism. An output shaft 50 of a motor 49 is connected to the clutch 39 through a drive shaft 46 and bevel gears 47 and 48, as shown in FIG. 5.
The shaft 46 is held by the frame 36 through a bracket 51. A solenoid 53 is supported by a bracket 52 and arranged below the clutch 39. The clutch 39 is stopped by a lever 54 of the solenoid 53 every time the clutch 39 is rotated by a half revolution.
A sprocket 56 is mounted on the shaft 50 of the motor 49, as shown in FIG. 6. The sprocket 56 is coupled to sprockets 60a and 60b respectively mounted on shafts 58 and 59 of the rollers 20 and 25 through a chain 57. A gear 74 is mounted on the shaft 59 of the roller 25. The gear 74 meshes with a gear 76 mounted on a shaft 73 of the roller 24 through a gear 75 mounted on a shaft 72 of the roller 23. In this manner, the inversion and variable mechanisms A and B are driven by the common motor 49.
The stacking apparatus 15 is controlled by a control system shown in FIG. 7. Referring to FIG. 7, reference numeral 61 denotes a microcomputer. The microcomputer 61 comprises a central processing unit (CPU) 62, I/0 ports 63a and 63b, a program control ROM 64 and a data storage RAM 65. The CPU 62 is connected to a section 66 of the copying apparatus through the port 63a. The CPU 62 is also connected to the switches 67, 21 and 22 through the port 63b. In addition, the CPU 62 is connected to a driver 70 through the port 63b. The motor 49, the solenoid 28, the clutch 39 and the solenoid 78 are actuated through the driver 70. It should be noted that reference numeral 71 denotes a voltage regulating device.
With the above arrangement, a single copying mode wherein each of a plurality of documents is copied once will be described. In the single copying mode, the sheet P with an image is conveyed along the path 41 in the housing 11. When the sheet P passes by the switch 43, the switch 43 arranged near the outlet of the path 41 is turned on. Upon the ON operation of the switch 43, an output signal is generated from the section 66 of the copying apparatus. This signal is transferred to the CPU 62 through the port 63a. The CPU 62 causes the driver 70 to operate the driver 70 through the port 63b, thereby actuating the solenoid 78. At the same time, the motor 49 in the tray 29 is started. The lever 18 is pivoted upward upon operation of the solenoid 78. The motor 49 drives the rollers 23, 24 and 25 and the rollers 20 through the chain 57.
In this state, the sheet P is discharged by the rollers 42, as shown in FIG. 8A and is conveyed in the path 17 since the lever 18 is pivoted upward. The switch 67 detects that the sheet P is fed in the path 17. A detection signal from the switch 67 is supplied to the CPU 62 through the port 63b. The CPU 62 counts a predetermined period of time (a time from which the trailing end of the sheet P is detected until the trailing end of the sheet P is separated from the roller 23). As shown in FIG. 8B, the CPU 62 stops counting the predetermined period of time and supplies a signal to the driver 70 which then drives the solenoid 28. Upon operation of the solenoid 28, the plate 26 is pivoted about the pin 26a in the direction of the arrow. As shown in FIG. 8C, the roller 27 at the distal end of the plate 26 is brought into rolling contact with the roller 25, thereby moving upward the trailing end of the sheet P on the plate 26. In this manner, the sheet P is inserted between the rollers 23 and 25. The solenoid 28 is held operative for a predetermined period of time. Thereafter, the solenoid 28 is deenergized in response to a signal from the CPU 62 so that the plate 26 is pivoted downward, thereby obtaining the initial state. The holding time of the solenoid 28 is when the trailing end of the sheet P is clamped by the rollers 23 and 25. Upon clamping of the sheet P by the rollers 23 and 25, the sheet P is conveyed in the path 19 and then discharged by the rollers 20 into the tray 29.
When the above operation is repeated, the image formation surfaces of the sheets P face down on the tray 29 while the images are formed on the upper surfaces of the sheets P. Therefore, the order of the copied sheets is the same as that of the documents.
Since the plate 26 is pivoted downward while the sheet P is inverted by the mechanism A and fed by the rollers 23 and 25, the next sheet P can be fed by the rollers 23 and 25 into the subtray 30.
A multicopying mode wherein each of a plurality of documents is copied 10 times will be described. In the multicopying mode, the sheets P are discharged in the tray 29 in the same manner as described above. However, in this case, every time 10 copied sheets are stacked, a drive signal is supplied from the section 66 to the driver 70 which energizes the solenoid 53 and then the clutch 39 before the next document is subjected to copying. Power of the motor 49 is transmitted to the pin 38 through the gears 48 and 47, the shaft 46 and the clutch 39, so that the pin 38 is eccentrically rotated. Upon eccentric rotation of the pin 38, the rod 37 is moved and the link 34 is pivoted as indicated by the alternate long and two short dotted lines in FIG. 4. The slider 31 is moved by a distance l along a lateral direction (i.e., a direction perpendicular to the discharge direction of the sheet P), so that the stacking position of the sheets P corresponding to the next document can be varied.
Thereafter, when 10 copied sheets for the second document are discharged and stacked in the same manner as described above, they are stacked on the sheets P of the first document in an offset manner.
Subsequently, the tray 29 is moved to stack every 10 sheets corresponding to each document in an offset manner.
A case will be described wherein only one document is copied once. In this case, the section 66 supplies a signal to the driver 70 to deenergize the solenoid 78. As shown in FIG. 9, the lever 18 is pivoted downward, and the sheet P is not inverted and discharged by the rollers 20 along the path 16. The sheet P is discharged into the tray 29 such that the copied surface faces upward.
According to this embodiment, the mechanism A is provided for inverting the sheet P and guiding it into the tray 29. When a plurality of documents are continuously copied, the sheets are discharged in the tray such that their image formation surfaces face downward, so that the sheets have the same order as that of the documents.
In addition, since the mechanism B is provided for moving the position of the tray 29, the copied sheets can be grouped in units of documents when each of the plurality of documents is copied a plurality of times.
Furthermore, the tray 29 is detachably mounted on the slider 31. When paper jam occurs on the subtray 30, the tray 29 can be removed to take away the jammed sheet P.
Furthermore, since the vertical portion 29a of the tray 29 is integrally formed with the tray 29, the stacked sheets P can be properly aligned even if the tray 29 is moved.
Furthermore, since the roller 27 is integrally formed with the plate 26, the structure can be simplified and the proper operation can be performed.
Furthermore, the mechanism A is provided below the tray 29, so that the space can be effectively utilized and the copied sheets can be easily removed.
Furthermore, since the roller 23 has the grooves 23a, the sheet P can be easily fed.
Furthermore, the lever 18 is provided for discharging the sheets such that the image formation surfaces face upward as needed.
Furthermore, since a common drive source is used for the mechanisms A and B, the structure can be simplified and is low in cost.
Furthermore, the projections 33 of the tray 29 are engaged with the recesses 32 of the slider 31, so that the tray 29 can be attached to or removed from the slider 31 with a one-touch operation.
The present invention is not limited to the embodiment described above. Various changes and modifications can be made within the spirit and scope of the invention.
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A recording apparatus records an image impression of an original on a sheet. The recording apparatus comprises a flip lever arranged to oppose a distal end of a first convey path for conveying the sheet recorded by a recording mechanism. The flip lever is movable between the first position where the sheet conveyed along the first convey path is guided in a second convey path and a second position where the sheet is guided in a third convey path. A temporary stacking tray is arranged to oppose a distal end of the second convey path and temporarily stacks the sheet guided by the flip lever from the first convey path to the second convey path while the first surface of the sheet faces upward. In front of the temporary stacking tray, an inverting mechanism is provided for conveying the sheet temporarily stacked on the temporary stacking tray to the third convey path through a fourth convey path without passing through the flip lever while the second surface opposing the first surface faces upward.
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BACKGROUND OF THE INVENTION
This invention retates to a structure and implement for positioning the light-receiving edge of a light conductor onto the focus of a lens.
It has often been the practice to focus solar ray by means of a lens, to guide solar rays into a light conductor and to transmit the solar ray through the light conductor to an optical desired position in order to use the solar ray for illumination or other purposes. One of such methods is to focus the solar ray by means of a Fresnel lens of about 40 cm diameter to guide the solar ray focussed by the lens into the light conductor having an edge surface of about 10 mm diameter arranged at the focus position of the lens, and to transmit the solar ray guided into the light conductor in such a manner through the light conductor to the optional desired position in order to use the solar ray for illumination or other purposes, for instance, as the light source for cultivating the plants in a room or an underground room, light source for nurturing the plants on the botton of the sea, or the light source for culturing chlorella, etc. However, according to such method, the focal distance of the lens turns out to be longer, for instance, about 40 cm, and therefore the device becomes large-scaled or voluminous. And further, the light collecting energy for each lens increases so that a highly heat-proof material needs to be used as the member placed near to the focus position of the lens, and the operator may probably be in danger of suffering from burning the operator's hands, etc. at the focus position when the operator performs the adjustment work for positioning the edge surface of the light conductor onto the focus position of the lens, and so on. According to the method, a large number of small lenses having a diameter of about 4 cm are used, and the edge surface of an optical fiber of 1 through 2 mm diameter is arranged at the focus position of each lens. The light collected by each lens is guided into the respective optical fibers, and the light delivered from the respective optical fibers is guided into an optical conductor having a large diameter, for instance a diameter of 10 through 30 mm and transmitted to the optional desired position through the light conductor.
According to this method mentioned above, the focal distance of the lens turns out to be small, for instance, about 4 cm. Therefore, it may be possible to realize the device manufactured in a small-scaled and thin style. On the contrary, since a large number of lenses are used, it may be troublesome to position the light-receiving edge surface of the optical fiber onto the focus of each lens and perform its maintenance operation.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a structure and implement for positioning the light-receiving edge of the optical fiber onto the focus of the lens.
It is another object of the present invention to provide a structure and implement for effectively collecting solar rays.
It is another object of the present invention to provide a structure and implement for protecting the operator from getting burnt, etc.
It is another object of the present invention to provide a structure and implement for enabling to simplify the adjustment work of positioning the light-receiving edge onto the focus position of the lens.
It is another object of the present invention to provide a structure and implement for facilitating the maintenance and management operation.
A structure and implement for positioning a light-receiving edge of an optical fiber onto the focus of a lens unitarily comprise a large number of lenses and a large number of optical fibers having a light-receiving edge arranged at the focus position of each lens. The structure and implement further comprise a base plate having a large number of holes bored in the direction of the optical axis of the lens. Each of the holes is bored corresponding to the focus position of the lens. The light-receiving edge of the optical fiber is inserted into each hole. The position of the optical fiber inserted into the hole is adjusted in the axial direction of the hole. After precisely positioning the light-receiving edge at the focus of the lens, the light-receiving edge is fixed at the position by means of a binding agent (adhesive).
The above and other objects, features and advantages of the present invention will become apparent from the following detailed descreption taken with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an outlined perspective view showing a solar ray collecting device as an example applied for the present invention.
FIG. 2 is a diagram for explaining the construction of an embodiment according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to a structure for guiding with a high accuracy the light focussed by a lens into an optical fiber, that is to say, a structure and an implement for accurately positioning the light-receiving edge of the optical fiber onto the location of the lens focus.
FIG. 1 is an outlined perspective view showing a solar ray collecting device as an example applied for the present invention. In FIG. 1, 1 is a cylindrical base block, 2 is a dome-shaped head cover, and 3 is a capsule composed of the base block and the head cover for the solar ray collecting device. Under the usage condition, the solar ray collecting device 10 is accommodated in the capsule 2 as shown in FIG. 1. The solar ray collecting device 10 comprises a number of lens groups 11 (for example, in the figures, 7 lens groups are shown, but 19, 37 or 61 groups may be used) for focussing the solar ray, a direction sensor 12 for detecting the direction of the sun, a supporting frame 13 for unitarily retaining the lens groups and sensor, a first rotating shaft 14 for rotating the supporting frame 13, a supporting arm 16 for rotatably supporting the rotating shaft 14, and a second rotating shaft 17 for rotating the supporting arm 16 around the shaft crossing perpendicularly to the first rotating shaft 14. When the direction sensor 12 detects the direction of the sun, it generates the detection signal which controls the first and second rotating shafts so as to always direct the lens to the direction of the sun. The solar ray focussed by the lens groups is guided into an optical conductor cable or the like not shown, the light-receiving edge of which is arranged on the location of the lens focus, and the focus, and the focussed solar ray is transmitted onto the optical desired place through the optical conductor cable. And then, in the solar ray collecting device as mentined above, each lens group 11 comprises a large number (for example 61 per one group) of lenses 21 of several centimeters diameter for example 4 cm, and the solar rays collected by each lens 21 are guided into an optical fiber per one lens. In order to effectively guide the solar ray focussed by each lens into the optical fiber, it is required that the light-receiving edge of the optical fiber is precisely positioned onto the position of lens focus. Especially, in the case of using a large number of lenses as stated heretofore, the positioning operation and the following maintenance turns out to be very troublesome.
The present invention has been done in view of the aforementioned situation. In particular, the present invention relates to the structure for accurately positioning the light-receiving edge of the optical fiber onto the position of the lens focus and the implement preferably used in the embodiment of the present invention, in a solar ray collecting device using a large number of lenses as mentioned above.
FIG. 2 is a diagram for explaining the construction of an embodiment according to the present invention. In FIG. 2, 21 is a lens for focussing the solar ray, 22 is an optical fiber into which the solar ray collected by the lens 21 is guided, 23 is a retaining member for retaining the optical fiber 22, 24 is a sleeve which is unitarily mounted on the optical fiber 22 at the light-receiving side of the optical fiber 22, 25 is a supporting plate for supporting the lens 21 and the retaining member 23. The supporting plate 25 has a hole 25a on the optical axis of the lens 21. Further, the retaining member 23 has holes 23a for injecting an adhesive agent (liquid) in order to bind the retaining member 23 to the supporting plate 25 and other holes 23b for injecting an adhesive agent (liquid) in order to bind the sleeve 24 to the retaining member 23. And then, in order to position the light-receiving edge 22a of the optical fiber 22 onto the focus of the lens 21, the retaining member 23 is slid on the support plate 25" so as to let the center of the lens 21 coincide with that of the optical fiber 22, and then, adhesive agent liquid is injected inwardly through the hole 23a of the retaining member 23 to bind the member 23 to the supporting plate 25 under that condition kept. Next, the optical fiber 22 is moved in the direction of the Z-axis so as to position the light-receiving edge 22a of the optical fiber onto the focus of the lens 21. Keeping that condition, adhesive agent liquid is injected inwardly through the hole 23b of the retaining member 23 to bind the sleeve 24 to the retaining member 23. Furthermore, in order to let the center of the lens 21 coincide with that of the optical fiber 22, though the center of the optical fiber 22 may be positioned onto that of the Fresnel lens stripe pattern by observing it with the naked eyes in the case of the Fresnel lens, more generally, the side of the light-discharging edge of the optical fiber 22 is guided to a photometer or the like, the parallel rays just like laser rays, etc. being radiated onto the lens 21 from the direction shown by an arrow A, the position on which the indication value of the photometer turns out to be maximum is searched by sliding the retaining member 23 on the support plate 25 in such manner as mentioned above, and then, adhesive agent liquid is injected inwardly through the hole 23a on that position in order to fix the retaining member 23 to the supporting plate 25. Next, the position of the optical fiber 22 to the Z-axis direction is determined. Positioning of the optical fiber 22 to the Z-axis direction is performed in such a manner as afore-mentioned. That is to say, after fixing the retaining member 23 to the supporting plate 25, the optical fiber 22 is moved along the Z-axis direction for the purpose of searching the position at which the indication value of the photometer turns out to be maximum, and adhesive agent is injected inwardly through the hole 23b at that position in order to fix the sleeve unitarily constructed together with the optical fiber 22 to the retaining member 23.
As is apparent from the above-mentioned description, it might be possible to precisely and surely position the light-receiving edge surface of the optical fiber onto the position of the lens focus by use of the simple means and manufacturing process, according to the present invention. And then, since almost all for portions are constructed unitarily as a whole, there may be no need of the following maintenance.
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A structure for positioning the light-receiving edge of an optical fiber comprises a large number of lens for focussing the light, and a large number of optical fibers, each having a photo-receiving edge arranged on the focus of the lens. A supporting plate has a large number of holes coaxial with each of the optical axis of said lens, and a retaining member retains the optical fiber movably along the direction of the optical axis. The retaining member is bound with an adhesive agent to the supporting plate, and the optical fiber is bound with an adhesive agent to the retaining member.
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The present invention relates to the field of gas turbine engines and is aimed in particular at a transition channel between two turbine stages.
BACKGROUND OF THE INVENTION
A multiple-bodied gas turbine engine comprises assemblies rotating independently of one another usually about one and the same axis. For example, a double-bodied engine comprises two assemblies, one called high pressure and the other low pressure. The high pressure body consists of a compressor and a turbine mounted on one and the same shaft. The high pressure compressor supplies the combustion chamber with air which itself delivers the combustion gases to the high pressure turbine. The low pressure body comprises a low pressure turbine receiving, through a channel called the transition channel and where necessary a distributor, the gases that have undergone a first expansion in the high pressure turbine.
One of the means of increasing the output of the low pressure turbine consists in reducing the aerodynamic load via an increase in the average radius of the latter. The radius of the high pressure turbine remaining unchanged, it follows that the geometry of the transition channel between the high pressure, HP, turbine and the low pressure BP, turbine is therefore to be adapted between its section for the inlet of the gases originating from the high pressure turbine and its outlet section emerging into the distributor for supplying the low pressure turbine. For aero engines, because of space and weight constraints, it is not opportune to lengthen the transition channel; it follows that the walls of the latter must have steep slopes and arrange a considerable diffusion. A limit is however imposed by the quality of flow that is to be retained at the walls; the thickening and even the detachment of the boundary layer must be avoided.
If the limits of slope and diffusion in the swan neck formed by the transition channel are exceeded, detachments of the boundary layer occur that are an unfavorable factor for the performance of the turbine. That would cancel out the gain provided by the increase in the average radius of the low pressure turbine.
To remedy this problem, a solution consists in re-energizing the boundary layer at the walls in order to prevent detachments of the boundary layer, by injecting a flow of fluid into the boundary layer.
Such a solution therefore allows the adoption of a transition channel from the HP turbine to the BP turbine:
with a steep slope in order to increase the average radius of the turbine and hence the output, with high diffusion in order to reduce the losses generated by the distributor of the low pressure turbine and hence increase the output of the BP turbine.
This solution is appropriate for any transition channel between two turbine sections, not only between the HP section and the BP section immediately downstream.
DESCRIPTION OF THE PRIOR ART
Patent application US2005/0279100 describes such an inter-turbine transition channel provided with a fluid blowing means. A gas bleed duct is arranged in the stream upstream of the high pressure turbine. This duct bypasses the high pressure turbine and emerges downstream of the latter substantially parallel with the external wall of the transition channel, in the zone where the detachment of the boundary layer is likely to occur. As is mentioned in this document, the injection of fluid allows the production of a channel whose external wall has a steep slope.
Because of the thermal and mechanical stresses, there are however difficulties in injecting fluid into the transition channel.
SUMMARY OF THE INVENTION
The subject of the present invention is a method for producing the structure of the transition channel allowing an effective injection of the fluid for reattaching the boundary layer.
According to the invention, the transition channel between a first turbine section and a second turbine section for a gas turbine engine, comprising a first radially external annular wall, a second radially internal annular wall, the first wall comprising orifices, in the form of slots, holes or other elements, for injecting a fluid into the channel in order to re-energize its boundary layer, is characterized in that the first wall consists of ring sector elements housed inside an annular ring, fluid supply means being arranged between the outside of the ring and said injection orifices.
According to a first embodiment, the supply means comprise openings arranged in the annular ring, cavities arranged in the ring sectors and communicating with the injection orifices, and connecting tubes fitted between said openings and said cavities.
According to another embodiment, the supply means comprise openings arranged in the annular ring, cavities arranged in the ring sectors and communicating with the injection orifices, and an annular channel, delimited by annular seals, arranged between the openings and the cavities and placing them in communication.
According to another embodiment, the fluid injection orifices in the ring sector elements are obtained by machining the ring sectors.
According to another embodiment, the fluid injection orifices are defined between openings machined in the sectors and guide elements fitted to the sectors.
Advantageously, according to a particular embodiment, the injection orifices are arranged in order to impart a tangential speed component to the fluid.
The invention also relates to a gas turbine engine comprising a first turbine section and a second turbine section connected via a transition channel, wherein the ring arranges a fluid distribution cavity with a turbine casing element, said casing element comprising a fluid supply orifice communicating with a bleed zone upstream of the transition channel. The bleed is carried out preferably at the compressor so that the injected air forms a film for protecting the wall.
More particularly, the ring sectors, forming the radially external annular wall of the transition channel, are fitted to the elements forming the distributor at the entrance to the second turbine section. According to one embodiment, the ring sectors form monobloc parts with the elements of the distributor.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail with reference to the appended drawings in which:
FIG. 1 shows in axial half-section the turbine section of a gas turbine engine of the prior art with a first turbine, a second turbine and a transition channel,
FIG. 2 is a partial view of the radially external portion of the transition channel and shows the arrangement according to a first embodiment of the invention,
FIG. 3 shows a partial view of the radially external portion of the transition channel with an arrangement according to another embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an exemplary architecture of the prior art of the turbine sections of a gas turbine engine. The casing 1 houses a first turbine rotor 2 . Here, it is the high pressure turbine of the engine. This turbine is fixedly attached to a first shaft. A second turbine 4 , here the low pressure turbine, receives the gases having undergone a first expansion in the turbine 2 . The expansion is split between several stages, mounted on a single rotor. The latter is fixedly attached to a shaft coaxial with the first and independent of the latter. A transition channel 6 is arranged between the two sections, more precisely between the rotor of the high pressure turbine and the distributor at the entrance to the low pressure turbine. Because of the expansion of the gases between the entrance to the high pressure stage and the exit from the low pressure section, the volume increases and the average diameter also. However, this increase remains compatible with the conditions of undisturbed flow.
In the context of the design studies to increase the output of the low pressure turbine, the profile of the aerodynamic channel is optimized. Amongst these optimizations, the increase in the slope at the entrance to the low pressure turbine is adopted in the transition channel which allows a rapid increase in the average radius of the low pressure turbine. In addition, this increase in section at the entrance to the low pressure distributor generated by a greater diffusion in the channel, generates an increase in performance on the first stage with a better acceleration in the distributor. Thin lines (D) in FIG. 1 show the contours of such an optimized profile.
However, a steep slope at the entrance to the low pressure turbine creates risks of detachments of the boundary layer along the external wall of the main flow originating from the high pressure turbine. These detachments greatly harm the performance of the BP turbine.
In the proposed solution, a significant gas flow is injected at the exit from the high pressure turbine at the wall in order to keep it at the wall. This injection of air is commonly called blowing.
FIG. 2 shows the technological integration of the blowing that is the subject of the invention in an engine environment example. The figure shows a portion, in axial section, of the transition channel 10 . This channel 10 is situated between the HP turbine 12 of which a portion of blade can be seen and the distributor 14 at the entrance to the BP turbine section of which a portion of blade is also seen. The blading of the HP turbine 12 can move inside an annular channel defined externally relative to the axis of the engine by a sealing ring 121 . This ring is attached in an internal casing element 123 , called the HP turbine casing. This casing is itself mounted in the external casing 20 . The turbine ring 121 is formed of a plurality of annular sectors and is held in the casing element 123 by means of an intermediate part 124 by means of clamps 121 A.
The annular transition channel 10 is defined between a first radially external wall 102 and a second radially internal wall not shown in FIG. 2 . The first wall 102 is formed of platforms in ring sectors extending axially between the HP turbine ring 121 and the distributor 14 of the first stage of the BP turbine. In axial section, as is seen in FIG. 2 , downstream, the first wall 102 is fixedly attached to the distributor 14 by a tongue connection 102 A in a groove 14 A. Upstream, the first wall 102 is pressing against the sealing ring 121 via a seal 121 B. Cavities 102 B are arranged upstream of the wall. These cavities 102 B are radially open outward, relative to the axis of the machine. They communicate with injection orifices 102 C that open into the transition channel 10 . The injection orifices 102 C are oriented substantially parallel to the surface of the wall 102 . To the extent that the gas stream originating from the HP turbine comprises a tangential component in the transverse plane relative to the axis of the engine, it is advantageous to give these orifices an orientation that is also tangential in the transverse plane.
The wall 102 is contained in an annular ring 104 of the same axis as that of the channel, of substantially frustoconical shape. This ring 104 , made particularly of metal sheet, extends axially between the sealing ring 121 and the distributor. More precisely, upstream, the ring presses via a seal 104 A against a radial flange 123 A of the HP turbine casing 123 that is close to the edge of the ring 121 or, as here, in the same transverse plane as the latter. Downstream, the ring 104 is held by a tongue and groove fastener 104 D fixedly attached to the HP casing 123 . An axial flange 102 D forms a bearing surface 104 E for the ring 104 .
The ring 104 comprises radial openings 104 B communicating with the cavities 102 B of the first wall by means of fitted connecting tubes 106 . These cylindrical tubes have, at their ends, surfaces with an axial section in the arc of a circle interacting with the walls of the openings 104 B on the one hand and of the cavities 102 B. The diameters are adjusted so as to form a sealed contact between the tubes and the cylindrical walls of the openings 104 B and the cavities 102 B. The gaseous fluid is guided through the connecting tube with no leak. A limited rotary movement of the tubes in their housings is therefore allowed so as not to immobilize the first wall relative to the ring.
The ring 104 arranges an annular space 110 with the wall of the turbine casing 123 downstream of the radial flange 123 A. A seal 104 C provides the seal downstream between the ring 104 and the wall 123 of the casing. Orifices 123 B arranged in the wall of the turbine casing 123 place the space 110 in communication with a fluid supply channel 112 . Thus the annular space 110 is delimited between the ring 104 , the casing 123 and the seals 104 A and 104 C.
When the engine is operating, the gaseous fluid is guided from the channel 112 into the space 110 through the orifices 123 B, then from the space 110 into the cavities 102 B of the first wall of the channel 102 from where it is injected into the channel 10 through the injection orifices 102 C in order to re-energize the boundary layer on the wall 102 .
The channel 112 communicates with a zone that is situated upstream of the HP turbine and that is at a higher pressure than exists in the transition channel 10 . By choosing to bleed the fluid at the compressor for example, it is possible to perform an additional function of thermal protection of the wall.
A variant embodiment is described with reference to FIG. 3 . The portions that have been simply modified relative to the description with reference to FIG. 2 carry the same reference number but with a prime. In this embodiment, the connecting tubes are replaced by a duct arranged via seals.
The space 110 ′ is defined between the turbine casing element 123 , the ring 104 ′ and two seals, one upstream 104 ′ and the other downstream 104 C. The ring 104 ′ is pierced, upstream, with orifices 104 B′ communicating with radial cavities 102 B′ arranged in the first wall 102 ′. Seals 102 ′F and 102 ′G ensure a gaseous flow between the openings 104 B′ and the cavities 102 B′ with no leak. The seal 102 ′F here is ring-shaped; it is housed between the ring and a radial flange arranged on the ring sector forming the first wall. The seal 102 ′G is in the form of metal sheet fixedly attached to the ring 104 ′ and pressing elastically against a radial flange of the ring sector forming the wall 102 ′.
The cavities 102 B′ communicate with the injection orifices 102 C′ in the channel 10 ; according to this embodiment, the orifices 102 C′ are arranged by a guide 102 C″ fitted to the first wall. The cavities 102 B′ are through-cavities and are partially closed by the guide 102 ″. As in the preceding embodiment, the injection orifices are advantageously oriented with a tangential component in the plane transversal to the axis of the engine.
Operation is the same as in the preceding case.
The solution of the invention makes it possible via the ring to isolate the ring sectors forming the first wall from the source of fluid constituted by the channel 112 , and to provide effective guidance to the injection orifices without loss of fluid.
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A transition channel between a first turbine section and a second turbine section for a gas turbine engine is disclosed. The channel includes a first radially external annular wall including ring sector elements housed inside an annular ring and orifices for injecting a fluid into the channel in order to re-energize the boundary layer thereof, a second radially internal annular wall, and a fluid supply device arranged between the space outside the ring and the injection orifices.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. patent application Ser. No. 12/713,855 filed on Feb. 26, 2010, which is hereby incorporated herein by reference.
TECHNICAL FIELD
[0002] An embodiment of the present invention relates generally to semiconductor devices and, more particularly, to a semiconductor device having bucket-shaped under-bump metallization (UBM) and a method of forming the same.
BACKGROUND
[0003] Integrated circuits (ICs) fabricated using complementary metal oxide semiconductor (CMOS) technologies are susceptible to alpha particles. Alpha particles may cause single event upsets or soft errors during operation of the IC. In particular, alpha particles can cause ionizing radiation when passing through semiconductor device junctions. The ionizing radiation can upset or flip the state of various semiconductor structures, such as a memory cell (e.g., static random access memory (SRAM) cell, such as a conventional 6-transistor or 6T-SRAM). A common source of alpha particles is the bump material used in assembling, packaging, and/or mounting ICs. For example, the Controlled-Collapse Chip Connection (C4) packaging technology utilizes solder bumps deposited on solder wettable metal terminals of the IC and a matching footprint of solder wettable terminals on a substrate. The solder typically includes approximately 95% to 97% by weight of lead (Pb), with the remainder being made up by tin (Sn), although other materials and percentages of materials can be employed. In general, the most common material used for bumps is lead or a lead alloy. As is well known in the art, lead is a source of alpha particles. Alpha particles from solder bumps can penetrate through the interconnect layer of an IC and reach the underlying semiconductor structures, potentially causing the aforementioned single event upsets.
[0004] Accordingly, there exists a need in the art for a method and apparatus for a semiconductor device and method of fabrication thereof configured to block alpha particles emitted by solder balls used in device packaging.
SUMMARY
[0005] In one embodiment, a semiconductor device includes a substrate having an active layer and interconnect formed on the active layer. The interconnect has a bond pad. A first under-bump metallization (UBM) layer is disposed over the bond pad and directly contacts the bond pad. A dielectric layer is disposed above the interconnect layer and has a via exposing at least a portion of the first UBM layer. A part of the dielectric layer is disposed above a side of the first UBM layer. A second UBM layer is disposed above the first UBM layer and forms a UBM bucket over the via. At least a portion of the UBM bucket is in the dielectric layer. The UBM bucket defines a region located in the dielectric layer for accommodating a portion of a solder ball. The first UBM layer extends laterally past a periphery of the solder ball when the solder ball is accommodated in the region defined by the UBM bucket. A dielectric cap layer is disposed on the dielectric layer and a portion of the second UBM layer.
[0006] A method of forming a semiconductor device includes forming a first under-bump metallization (UBM) layer over a bond pad and directly contacting the bond pad. The bond pad is in the interconnect formed on the active layer of the substrate. A dielectric layer is formed above the interconnect and has a via exposing at least a portion of the first UBM layer. A part of the dielectric layer is above a side of the UBM portion. A second UBM layer is formed over the via and the first UBM layer is shaped as a UBM bucket. A dielectric cap layer is formed over the dielectric layer and a portion of the second UBM layer. The UBM bucket is formed so that at least a portion of the UBM bucket is in the dielectric layer, and the UBM bucket defines a region located in the dielectric layer for accommodating a portion of a solder ball. The first UBM layer extends laterally past a periphery of the solder ball when the solder ball is accommodated in the region defined by the UBM bucket.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Accompanying drawing(s) show exemplary embodiment(s) in accordance with one or more aspects of the invention; however, the accompanying drawing(s) should not be taken to limit the invention to the embodiment(s) shown, but are for explanation and understanding only.
[0008] FIG. 1 is a cross-section of a semiconductor device according to the prior art;
[0009] FIG. 2 is a cross-section of a semiconductor device according to one or more embodiments of the invention;
[0010] FIG. 3 is a flow diagram depicting a method of forming a semiconductor device according to one or more embodiments of the invention;
[0011] FIGS. 4A-4D depict semiconductor device cross-sections corresponding to steps of the method of FIG. 3 ;
[0012] FIG. 5 is a flow diagram depicting another method of forming a semiconductor device according to one or more embodiments of the invention;
[0013] FIGS. 6A-6E depict semiconductor device cross-sections corresponding to steps of the method of FIG. 5 ;
[0014] FIG. 7 is a flow diagram depicting another method of forming a semiconductor device according to one or more embodiments of the invention;
[0015] FIGS. 8A-8D depict semiconductor device cross-sections corresponding to steps of the method of FIG. 7 ; and
[0016] FIG. 9 is a flow diagram depicting another method of forming a semiconductor device according to one or more embodiments of the invention.
DETAILED DESCRIPTION
[0017] A semiconductor device having bucket-shaped under-bump metallization (UBM) and a method of forming the same is described. In some embodiments, a dielectric layer is patterned over the passivation layer of an IC substrate to have vias exposing bond pads. In some embodiments, the vias are tapered vias. A UBM layer is formed in the via such that a UBM bucket is formed over the bond pad. The IC substrate can then be bumped such that solder balls are formed in the UBM buckets. Alpha particles from the portion of the solder ball in the UBM bucket are blocked by the UBM metal from penetrating and affecting the active layer of the substrates. Alpha particles from the portion of the solder ball above the UBM bucket have angles of incidence and/or path lengths that prevent such particles from reaching the active circuitry. Thus, the UBM bucket reduces or eliminates penetration of alpha particles to the active circuitry, thereby reducing or eliminating single event upsets caused by such alpha particles. These and further aspects of the invention may be understood with reference to the following drawings.
[0018] FIG. 1 is a cross-section of a semiconductor device 100 according to the prior art. The semiconductor device 100 includes a substrate 102 having an active surface 104 and interconnect 106 disposed on the active surface 104 . The interconnect 106 includes a bond pad 108 . In a typical flip-chip packaging process, such as C4 packaging, an under-bump metal (UBM) layer 112 is formed over the bond pad 108 . A solder bump 110 is then formed on the UBM layer 112 . The UBM layer 112 is a flat metal layer that is self-aligned to the solder bump 110 such that the solder bump protrudes beyond the UBM layer 112 at its periphery. While the UBM layer 112 may be thick enough to block alpha particles emitted from the central lower surface of the solder bump 110 , the UBM layer 112 does not block alpha particles emitted from areas of the solder bump 110 that protrude beyond the UBM layer 112 . Alpha particles other than those close to vertical incidence will bypass the UBM layer 112 and could reach the underlying active surface 104 . Thus, a “donut” shape of single event upsets can be detected in underlying circuits on the active surface 104 caused by peripheral and non-vertical incidence alpha particles emitted by the solder ball 110 .
[0019] FIG. 2 is a cross-section of a semiconductor device 200 according to one or more embodiments of the invention. The semiconductor device 200 includes a substrate 202 having an active surface 204 and interconnect 206 disposed on the active surface 204 . The interconnect 206 can include multiple layers of conductive interconnect, including a top-most layer having bond pads, such as bond pad 216 . A passivation layer 208 is formed over the substrate 202 , exposing at least a portion of the bond pad 216 . A dielectric layer 210 is formed over the passivation layer 208 . A tapered via is formed through the dielectric layer 210 exposing the bond pad 216 . A “tapered via” is a hole through the layer that is at least partially frusto-conical in shape (a portion of the tapered via may be cylindrical in shape). A UBM layer 218 is formed in the tapered via and over the bond pad 216 . Thus, a “bucket-shaped” UBM is formed for supporting a solder ball 214 . A dielectric cap layer 212 is formed on the dielectric layer 210 and over a portion of the UBM layer 218 (e.g., the portion of the UBM layer 218 that protrudes above the dielectric layer 210 ).
[0020] The dielectric and passivation layers may be formed of any dielectric material known in the art, such as SiO 2 . The UBM layer 218 may be formed of various metals or metal alloys comprising Ti, Ni, Cu, Zn, Sn, and the like. The UBM layer 218 may have a thickness adapted to sufficiently block alpha particles. For example, in some non-limiting embodiments, the UBM layer 218 made of a Cu/Ni alloy may have a thickness between 5 and 10 μm. The solder ball 214 fully fills the bucket of the UBM layer 218 and includes a portion extending above the dielectric layer 212 . Alpha particles emitted anywhere from the portion of the solder ball 214 in the UBM bucket are blocked by the UBM layer 218 . Alpha particles emitted anywhere from the portion of the solder ball 214 extending above the dielectric cap layer 212 are not blocked, but have an angle of incidence and/or path lengths such that the particles will not penetrate through to the active surface 204 . In this manner, the bucket-shaped UBM in the UBM layer 218 reduces or eliminates single event upsets during IC operation caused by alpha particles.
[0021] FIG. 9 is a flow diagram depicting a method 900 of forming a semiconductor device according to one or more embodiments of the invention. The method 900 begins at step 902 , where a semiconductor substrate having an active layer and interconnect formed on the active layer is obtained. At step 904 , a dielectric layer is formed above the interconnect having a tapered via exposing at least a portion of a first metal layer. In some embodiments, the first metal layer is a bond pad on a top-most layer of the interconnect. In other embodiments, the first metal layer is a first UBM layer formed on a bond pad of the interconnect. In some embodiments, the dielectric layer is a passivation layer formed on the interconnect. In other embodiments, the dielectric layer is formed over a passivation layer formed on the interconnect. At step 906 , a UBM layer is formed over the tapered via and the first metal layer to form a UBM bucket in the tapered via. The UBM layer in step 906 may be a second UBM layer in embodiments where the first metal layer is a first UBM layer. At step 908 , a dielectric cap layer is formed over the dielectric layer and a portion of the UBM layer forming the UBM bucket. At step 910 , a solder ball can be formed in the UBM bucket having a first portion contained within the UBM bucket and a second portion extending above the dielectric cap layer. More detailed exemplary embodiments of the method 900 are described below.
[0022] FIG. 3 is a flow diagram depicting a method 300 of forming a semiconductor device according to one or more embodiments of the invention. FIGS. 4A-4D depict semiconductor device cross-sections corresponding to steps of the method 300 . Elements in FIGS. 4A-4D that are the same or similar to those of FIG. 2 are designated with identical reference numerals. At step 302 , a semiconductor substrate having a passivation layer formed thereon is obtained. FIG. 4A shows the substrate 202 having a passivation layer 402 formed on the interconnect 206 . The substrate 202 may be formed using conventional semiconductor processes.
[0023] At step 304 , a dielectric layer is deposited on the passivation layer and a passivation mask is used to selectively etch a tapered via in the dielectric layer to expose at least a portion of a bond pad. The tapered via may be formed using conventional deposition, photolithographic, and etching processes. FIG. 4B shows the passivation and dielectric layers 208 and 210 and a tapered via 404 formed therein. The dielectric layer 210 may be thick relative to the passivation layer 208 . For example, in a non-limiting embodiment, the dielectric layer 210 may have a thickness between 20 and 60 μm (whereas the passivation layer 208 may have a thickness between 5 and 7 μm). The dielectric layer 210 may be generally sized according to the size of the solder balls used in device packaging.
[0024] At step 306 , a UBM layer is deposited over the dielectric layer, tapered via and bond pad, and a UBM mask is used to selectively etch the UBM layer to form a UBM bucket in the tapered via. The UBM bucket may be formed using conventional deposition, photolithographic, and etching processes. The UBM mask may be oversized from the baseline UBM layer such that the UBM bucket fills the tapered via. FIG. 4C shows the UBM layer 218 having a UBM bucket 406 formed over the bond pad 216 .
[0025] At step 308 , a dielectric cap layer is deposited over the dielectric layer and the UBM layer, and a cap mask is used to selectively etch the dielectric cap layer to expose a portion of the UBM layer. The openings for the UBM layer may be formed using conventional deposition, photolithographic, and etching processes. The cap mask may be oversized from the passivation mask such that the dielectric cap layer covers the portions of the UBM bucket that extend above the dielectric layer. FIG. 4D shows the dielectric cap layer 212 formed over the dielectric layer 210 and a portion of the UBM layer 218 . A solder ball can then be formed in the UBM bucket 406 , as shown in FIG. 2 .
[0026] In some embodiments, the dielectric layer 210 can be omitted, and the passivation layer 208 can be formed having the same or similar thickness as the dielectric layer 210 .
[0027] FIG. 5 is a flow diagram depicting a method 500 of forming a semiconductor device according to one or more embodiments of the invention. FIGS. 6A-6E depict semiconductor device cross-sections corresponding to steps of the method 500 . Elements in FIGS. 6A-6E that are the same or similar to those of FIG. 2 are designated with identical reference numerals. At step 502 , a semiconductor substrate having a passivation layer formed thereon is obtained. FIG. 6A shows the substrate 202 having a passivation layer 601 formed on the interconnect 206 . The substrate 202 may be formed using conventional semiconductor processes.
[0028] At step 504 , a passivation mask is used to etch the passivation layer to expose a portion of each bond pad. At step 505 , a first UBM layer is deposited over the passivation layer and the bond pad, and a first UBM mask is used to etch the first UBM layer to form a first UBM portion (“first UBM layer”). The first UBM portion can be formed using conventional deposition, photolithographic, and etching techniques. FIG. 6B shows a first UBM portion 602 formed over the passivation layer 208 and the bond pad 216 .
[0029] At step 506 , a dielectric layer is deposited on the passivation layer and the first UBM portion, and a dielectric mask is used to selectively etch a tapered via in the dielectric layer to expose at least a portion of the first UBM portion. The tapered via may be formed using conventional deposition, photolithographic, and etching processes. FIG. 6C shows the dielectric layer 210 and a tapered via 604 formed therein. The dielectric layer 210 may be thick relative to the passivation layer 208 . For example, in a non-limiting embodiment, the dielectric layer 210 may have a thickness between 20 and 60 μm. The dielectric layer 210 may be generally sized according to the size of the solder balls used in device packaging.
[0030] At step 508 , a second UBM layer is deposited over the dielectric layer, tapered via and first UBM portion, and a second UBM mask is used to selectively etch the second UBM layer to form a UBM bucket in the tapered via. The UBM bucket may be formed using conventional deposition, photolithographic, and etching processes. The second UBM mask may be oversized from the baseline UBM layer such that the UBM bucket fills the tapered via. FIG. 6D shows the UBM layer 218 having a UBM bucket 606 formed over the first UBM portion 602 in the tapered via 604 .
[0031] At step 510 , a dielectric cap layer is deposited over the dielectric layer and the second UBM layer, and a cap mask is used to selectively etch the dielectric cap layer to expose a portion of the second UBM layer. The openings for the second UBM layer may be formed using conventional deposition, photolithographic, and etching processes. The cap mask may be oversized from the passivation mask such that the dielectric cap layer covers the portions of the UBM bucket that extend above the dielectric layer. FIG. 6E shows the dielectric cap layer 212 formed over the dielectric layer 210 and a portion of the UBM layer 218 . A solder ball can then be formed in the UBM bucket 606 , as shown in FIG. 2 .
[0032] The process 500 may be used to form a UBM bucket over a bond pad metal that requires two different UBM materials, such as a copper bond pad (i.e., one UBM material for adhering to the bond pad, and another UBM material for adhering to a solder ball).
[0033] FIG. 7 is a flow diagram depicting a method 700 of forming a semiconductor device according to one or more embodiments of the invention. FIGS. 8A-8D depict semiconductor device cross-sections corresponding to steps of the method 700 . Elements in FIGS. 8A-8D that are the same or similar to those of FIG. 2 are designated with identical reference numerals. At step 702 , a semiconductor substrate having a passivation layer formed thereon is obtained. FIG. 8A shows the substrate 202 having a passivation layer 801 formed on the interconnect 206 . The substrate 202 may be formed using conventional semiconductor processes.
[0034] At step 704 , a dielectric layer is deposited over the passivation layer, and a passivation mask is used to etch the dielectric and passivation layer to expose a portion of each bond pad. FIG. 8B shows a dielectric layer 802 formed over the passivation layer 208 and having a via 804 exposing the bond pad 216 . The via 804 may be cylindrical in shape. The dielectric layer 802 is thick relative to the passivation layer 208 (e.g., between 20 and 60 μm or other thickness depending on solder ball size).
[0035] At step 706 , a metal seed layer is deposited over the dielectric layer and the bond pad, and the seed layer is polished to form a seed bucket in the via. At step 708 , a UBM layer is electroplated over the seed bucket to form a UBM bucket. The seed and UBM buckets may be formed using conventional deposition, polishing, and electroplating processes. FIG. 8C shows a seed layer 806 and a UBM layer 808 forming a bucket over the bond pad 216 in the via of the dielectric layer 802 .
[0036] At optional step 710 , the dielectric layer can be removed by etching. The dielectric layer can be removed if necessary to control passivation layer stress. FIG. 8D shows the substrate 202 with the UBM bucket and the dielectric layer 802 removed. A solder ball 810 is shown formed in the UBM bucket formed by the seed layer 806 and the UBM layer 808 . A first portion of the solder ball 810 is formed in the UBM bucket, and a second portion of the solder ball 810 extends above the UBM bucket. Alpha particles emitted from the first portion of the solder ball 810 in the UBM bucket are blocked by the UBM metal, and alpha particles emitted from the second portion of the solder ball 810 are not blocked, but do not penetrate to the active surface 204 due to the angle of incidence and path length.
[0037] While the foregoing describes exemplary embodiment(s) in accordance with one or more aspects of the present invention, other and further embodiment(s) in accordance with the one or more aspects of the present invention may be devised without departing from the scope thereof, which is determined by the claim(s) that follow and equivalents thereof. Claim(s) listing steps do not imply any order of the steps. Trademarks are the property of their respective owners.
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A semiconductor device includes a first under-bump metallization (UBM) layer disposed over a bond pad, a dielectric layer above an interconnect layer having a via exposing at least a portion of the first UBM layer. A second UBM layer is disposed above the first UBM layer and forms a UBM bucket over the via. The first UBM layer and UBM bucket are configured to support a solder ball and can advantageously block all alpha particles emitted by the solder ball having a relevant angle of incidence from reaching the active semiconductor regions of the IC. Thus, soft errors, such as single event upsets in memory cells, are reduced or eliminated.
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GOVERNMENT RIGHTS
This invention was made with government support under Contract No. GM 44154 by the National Institutes of Health. The government has certain rights in the invention.
TECHNICAL FIELD
The present invention relates to the synthesis of carbohydrate molecules, and particularly to the synthesis of compounds related to 2-deoxyfucose.
BACKGROUND ART
2-Deoxy-L-fucose (2,6-dideoxy-L-galactose) is a constituent of rhodomycins, cinerubins A and B, the antibiotic azalomycins-B Horton et al., Method's Carbohydr. Chem., 8:201(1980) and the citations therein! and the anthracycliens Florent et al., J. Med. Chem., 36:1364(1993)!. L-Fucose is a constituent of sialyl Lewix X and sialyl Lewis A molecules that are involved with cellular adhesion mediated by the E- and P-selectins Phillips et al., Science, 250:1130(1990); Walz et al, Science, 250:1132(1990); U.S. Pat. Nos. 5,079,353 and 5,296,594; Berg et al., Biochem. Biophys. Res. Commun., 184:1048(1992), Berg et al, J. Biol. Chem., 23:14869(1991)!.
Aldolases are a group of enzymes which catalyze C--C bond formation, often in a highly stereoselective way. Over thirty aldolases have been identified so far and several have been used in organic synthesis. Wong et al., Enzymes in Synthetic Organic Chemistry, Pergamon, Oxford (1994) Chapter 4.! The mild reaction conditions, high stereoselectivity, and the minimal use of protective group chemistry make the use of aldolases an interesting alternative to the chemical aldo reactions. Most aldolases catalyze the condensation of an aldehyde with a ketone donor, giving a ketone as product. The enzyme 2-deoxyribose-5-phosphate aldolase (DERA, EC 4.1.2.4) Barbas et al., J. Am. Chem. Soc., 112:2013 (1990); Chen et al., J. Am. Chem. Soc., 114:741 (1992); Wong et al., J. Am. Chem. Soc., 117: (1995) in press; Gijsen et al., J. Am. Chem. Soc., 116:8422 (1994)!.
In view of the importance of fucose and 2-deoxyfucose and their related compounds (analogues and derivatives), it would be of importance to be able to prepare such compounds with relative ease. The disclosures that follow describe several such synthesis that utilize the enzyme 2-deoxyribose-5-phosphate aldolase.
BRIEF SUMMARY OF THE INVENTION
One aspect of the invention contemplates the use of 2-deoxyribose-5-phosphate aldolase (DERA) to prepare a pentose product of Formula I ##STR1##
wherein X is O or S, and R is selected from the group consisting of hydrogen, C 1 -C 4 alkyl and phenyl. That process comprises the steps of:
(a) admixing an aldehyde of Formula II ##STR2##
wherein X and R are as defined above, with acetaldehyde and DERA in an aqueous medium having a pH value of about 6.5 to about 8.5 and at a temperature of about 5° C. to about 45° C. to form a reaction mixture.
(b) That reaction mixture is maintained at that temperature and pH value for a time period sufficient for the product to form.
(c) The product is then recovered.
A particularly preferred aspect of the above process uses 2-deoxyribose-5-phosphate aldolase (DERA) to prepare a 2-deoxy-5-substituent-L-lyxo-pentose product in which the 5-substituent is C 1 -C 4 alkyl or phenyl. That process comprises the steps of:
(a) admixing an aldehyde of Formula III ##STR3##
wherein R is C 1 -C 4 alkyl or phenyl, with acetaldehyde and DERA in an aqueous medium at a pH value of about 7 to about 8 and at a temperature of about 15° C. to about 35° C. to form a reaction mixture in which acetaldehyde is in stoichiometric excess over the aldehyde of Formula III.
(b) The reaction mixture set forth is maintained in the absence of light at that temperature and pH value for a time period sufficient for the product to form.
(c) The product is then recovered.
Another aspect of this invention is a "one pot" synthesis of a 2,6-dideoxy hexose that is also a fucose derivative. This process uses 2-deoxyribose-5-phosphate aldolase (DERA) in a single vessel for the synthesis of a product compound of Formula V ##STR4##
wherein R 2 is selected from the group consisting of hydrogen, C 1 -C 4 alkoxy, halo and azido groups. Here, the process comprises the steps of:
(i) admixing the following materials in an aqueous medium at a pH value of about 6.5 to about 8.5 and at a temperature of about 5° C. to about 45° C. in a single reaction vessel to form a reaction mixture:
(a) acetaldehyde donor;
(b) R 2 -substituted acetaldehyde acceptor; and
(c) DERA
wherein the molar ratio of donor to acceptor is about 2:1 to about 4:1 and DERA is present in an amount of about 125 to about 150U per millimole of the donor and acceptor combined.
(ii) The admixture is maintained at that temperature and pH value for a time period sufficient for the product compound to form.
(iii) The product compound is then recovered.
DETAILED DESCRIPTION OF THE INVENTION
One aspect of the invention contemplated the use of 2-deoxyribose-5-phosphate aldolase (DERA) in a process to prepare a pentose product of Formula I, below, whose R group, when other than hydrogen, and hydroxyls are in the stereochemical configuration of L-fucose. ##STR5##
In Formula I, R is selected from the group consisting of hydrogen, C 1 -C 4 alkyl and phenyl and X is S (sulfur) or O (oxygen).
In accordance with the process of this aspect of the invention, an aldehyde of Formula II, below, where R and X are as above, ##STR6## is admixed with acetaldehyde and DERA in an aqueous medium at a pH value of about 6.5 to about 8.5 and at a temperature of about 5° C. to about 45° C. to form a reaction mixture.
That reaction mixture is maintained at the recited pH value and temperature for a time period sufficient for the product of Formula I to form, and that product is thereafter recovered.
This process is illustrated generally in the top line of Scheme 1, below, and more specifically in the following two lines, wherein Compounds 2a, 2b and 4 are shown to be prepared from compounds of Formulas III (Compounds 1a and 2b) and IV (Compound 3). Product yields are shown adjacent to the products. ##STR7##
Acetaldehyde is often referred to herein and in the art as the donor substrate, and the second aldehyde (Formula II) is the acceptor substrate, or more simply as donor and acceptor. It is preferred that the acetaldehyde be in stoichiometric excess over the acceptor. The ratio of donor to acceptor is typically about 1.5:1 to about 5:1 on a molar basis, and more preferably at about 2.5:1 to about 4:1.
The pH value noted before of the reaction mixture is typically between about 6.5 and about 8.5, and is more preferably about 7.0 to about 8.0. A pH value of about 7.3 is most preferred. It is also preferred that the pH value of the initially formed reaction mixture be the same during the maintenance step; i.e., within about 0.2 pH units of each other, but this preference is not critical.
The process is also preferably carried out in the absence of light; i.e., in the dark. The components are thus admixed in the light, and the resulting reaction mixture is shielded from the light by any convenient means. The process is also preferably carried out in the absence of oxygen so the process is typically carried out in an atmosphere of nitrogen, argon or a similar gas.
Turning now to the reactants, acetaldehyde (CH 3 CHO) is one reactant that is a donor in that acetaldehyde provides a carbanion that donates its pair of electrons in forming a covalent bond with the carbonyl carbon of the acceptor aldehyde of Formula II. ##STR8##
The compound of Formula II is shown with particular stereochemistry of the hydroxyl group of the carbon adjacent to the carbonyl group. That 2-position carbon thus has an R configuration. The configuration at the 3-position is not defined inasmuch as the R group can be hydrogen. However, when an R group is other than hydrogen, the configuration of the 3-position carbon is preferably S so that as shown, both the OH and XH groups extend below the plane of the page and can be shown using a dashed-wedge bond, as at position 2.
The configuration of the 3-position carbon atom quite unexpectedly plays some role in the rate of the aldol condensation reaction even though the bond that is formed is at the 1-position, two atoms removed. Thus, it was reported Chen. et al., J. Am. Chem. Soc., 114:741(1992)! that a compound having a 2R,3S configuration and a terminal hydroxyl group exhibited a relative rate of zero when reacted with acetaldehyde in the presence of DERA, whereas an isomeric compound with a 2R,3R configuration exhibited a relative rate of 0.3 under conditions in which dihydroxyacetone phosphate exhibited a relative rate of 100. Thus, whereas the Chen et al., paper could be taken to suggest that no reaction would take place here, relatively high yield reactions were found here, as noted in Scheme 1.
Exemplary C 1 -C 4 alkyl R groups include methyl, ethyl, propyl, isopropyl, butyl and sec-butyl. Methyl is a preferred R group when X is O, whereas hydrogen is a preferred R group when X is S.
The acceptor aldehydes have the preferred Formulas III and IV when X is O and S, respectively. These structural formulas are shown below. ##STR9##
The amount of DERA utilized in these reactions can be very broad such as about 80 to about 100 or more units (U) of enzyme per millimole of combined donor and acceptor aldehydes. Use of greater amounts of enzyme do not increase the yield of products. It is preferred to use about 90 to about 100U of enzyme per millimole of combined aldehydes, with those aldehydes being present at a before-stated ratio.
Another contemplated aspect of this invention is the use of DERA to carry out multiple condensation reactions, and more particularly, three condensations. These reactions were first reported in Gijsen et al., J. Am. Chem. Soc., 116: 8422 (1994). The general reaction is illustrated in Scheme 2, below, wherein R 2 is selected from the group consisting of hydrogen, C 1 -C 4 alkoxy, halo and azido. ##STR10##
In Scheme 2, it is seen that one mole of an R 2 -containing acetaldehyde derivative acceptor condenses with one mole of acetaldehyde as donor in a DERA-catalyzed reaction to form the 4-substituted-3-hydroxybutanal of Formula IV. That molecule then acts as acceptor for another mole of acetaldehyde as donor in a DERA-catalyzed condensation to form a compound of Formula V that is subsequently recovered.
It is believed that a multiple condensation as shown in Scheme 2 occurs here, but not in the previously discussed reactions because the β-hydroxyaldehyde of Formula IV cannot readily form a hemiacetal, which formulation effectively removes the hemiacetal from the reaction. Thus a compound of Formula II (i.e., a compound of Formulas III or IV) can form such an acetal.
In the above scheme, an exemplary C 1 -C 4 alkoxy group includes methoxy, ethoxy, iso-propoxy and butoxy groups, whereas an exemplary halo group includes fluoro, chloro, bromo and iodo groups, with chloro being preferred.
A compound such as 2,4-dideoxyfucose formed where R 2 is hydrogen is an intermediate used in the preparation of compactin, a cholesterol-lowering drug. The 2,4-dideoxyfucose is oxidized to the lactone that is a derivative of mevinic acids that are HMG-CoH reductase inhibitors.
A process contemplated here is carried out as described before for the first-mentioned process for using DERA, with two exceptions.
A first exception is the molar ratio of acetaldehyde donor to R 2 -substituted acetaldehyde acceptor. Inasmuch as two moles of acetaldehyde are consumed here, that ratio is preferably about 2:1 to about 4:1 on a molar basis.
A second exception is that the DERA is used in a larger amount to improve yield of the 2,4,6-trideoxy hexose product of Formula V. Thus, DERA is used here at about 125 to about 150 or more units per millimole of the combined donor and acceptor aldehydes used at an above-discussed molar ratio.
Results and Discussion
E. coli cells from the strain DH5α (ATCC 86968), transformed with the plasmid pVH17 containing the DERA gene, were used to provide about 124,000U of DERA per 6L of culture. Using lysozyme provided a convenient method for obtaining cell-free extracts, and is comparable to the disruption of the cells in a French Press (˜1600 U/g of cells) Barbas, et al., J. Am. Chem. Soc., 112:2013 (1990)!. The lysozyme method was especially useful when processing a large volume of cells. A net increase of 251 percent in the recovered activity was obtained after ammonium sulfate precipitation, salt removal and buffer exchange, compared to only about 30 percent recovered activity after overnight dialysis using tubing with a molecular weight cut off of 5000.
This new strategy for purification was based on the further use of anion exchange chromatography and chromatofocusing. Scale-up of the anion exchange chromatography was relatively easy as DERA was eluted in the void volume. Further purification by chromatofocusing using a pH gradient from 6 to 4 gave a main peak corresponding to DERA which upon analysis by SDS-PAGE revealed a single band of 28 kD. However, further analysis by isoelectrofocusing (IEF) revealed the existence of two more proteins. A narrower pH range (5.5-4.5) was used, and the peak containing DERA activity was analyzed by SDS-PAGE and IEF. A single band was obtained in both cases.
This is the first reported purification to homogeneity of 2-deoxyribose-5-phosphate aldolase that is especially noteworthy as the purification sequence produced an overall yield of 83 percent. For crystallization, DERA was dialyzed against Tris-HCl and concentrated to 10 mg/mL; crystals were immediately obtained upon treatment with polyethylene glycol Wong et al., Enzymes in Synthetic Organic Chemistry, Pergamos, Oxford (1990) Chapter 4!.
It was found that using DERA after the ammonium sulfate precipitation was a convenient method for using DERA in synthesis. However, the cell free extracts usually produced similar results.
Using α-hydroxyaldehydes with different substitution at the β-position (3-position), a variety of sugars were produced. Due to DERA's selectivity for D-2-hydroxyaldehydes, a single diastereomer was isolated when racemic 3-thioglyceraldehyde (Compound 3) was used as acceptor. Compound 3 produced 2-deoxy-5-thio-D-erythro-pentose in 33 percent yield as a mixture of α- and β-anomers.
2-Deoxy-L-fucose (Compound 2a), was synthesized from Compound la which is available from the Sharpless asymmetric dihydroxylation Henderson et al., J. Am. Chem. Soc., 116:558 (1994)!. Dihydroxyaldehyde Compound 1b afforded the unusual sugar Compound 2b in an analogous manner.
When acetaldehyde is used as the donor and acceptor, the resulting β-hydroxyaldehyde cannot form an internal hemiacetal, which results in an aldehyde being available for a second aldol reaction with acetaldehyde. The aldehyde resulting from this second addition, 2,4,6-trideoxy-D-hexapyranoside Compound 5, exists as the hemiacetal and was isolated.
When α-substituted acetaldehydes are used that contain functionality that will not cyclize after the first aldol reaction, the products from the sequential aldol reaction then cyclize in the pyranose form, stopping the polymerization after the addition of two acetaldehyde monomers. In this manner, 2,4-dideoxyhexoses with various substituents at the six position (Compounds 6-8) were also obtained Gijsen et al., J. Am. Chem, Soc., 116:8422 (1994)!.
Materials and Methods
Fast Protein Liquid Chromatography was performed on a Pharmacia FPLC system with columns purchased from Pharmacia. SDS-PAGE and IEF were performed with a Pharmacia PhastSystem instrument, using preformulated gels from the same company. UV and visible spectroscopy were obtained with a Beckman DU-70 Spectrophotometer at 25° C. NMR spectra were obtained on Bruker AMX-400 or AMX-500 spectrometers. High resolution mass spectra (HRMS) were obtained on a VG ZAB-ZSE Mass Spectrometer in electron impact (EI), fast atom bombardment (FAB), or with solid probe. All chemicals and enzymes, except DERA, were purchased from Aldrich, Sigma or Cambridge Isotope Laboratories.
EXAMPLE 1
Preparation of the Enzyme, DERA
The enzyme "DERA", 2-deoxyribose-5-phosphate aldolase was obtained by recombinant methods that follow:
A. Preparation of cell-free extract using lysozyme
To a suspension of E. coli cells strain DH5α (ATCC 86963), in Tris buffer (8 mL/g cells, 50 mM, pH 8.0), were added EDTA 50 mM, pH 8.2), and lysozyme (2 mg/g cells). The suspension was gently stirred at room temperature for one hour, and the suspension kept at 4° C. overnight. The preparation was gently sonicated for 20 minutes to decrease viscosity, DNase (10 μg/g cells) and MgCl 2 (0.95 μg per mL of preparation) were added and the mixture refrigerated for 20 minutes. The mixture was then centrifuged for 30 minutes at 16000×g, and the supernatant was used in the next purification steps.
In order to assess the efficiency of the above method, a cell-free extract was prepared by disruption of the above E. coli cells in a French Press. Five grams of cells were suspended in Tris buffer (45 mL, 50 mM, pH 8.0) and lysed twice in a French Press at 16,000 lb/in. After centrifugation for 30 minutes at 16,000×g, total proteins and DERA activities were measured in the supernatant and found to be similar to DERA activities in cell-free extracts obtained by the lysozyme method.
B. Purification of DERA
Streptomycin sulfate was added at 4° C. with stirring to the cell-free extract obtained by digestion of the cells with lysozyme until a concentration of 1 percent was obtained, and stirring was continued for 20 minutes. The solution was then centrifuged for 30 minutes at 16,000×g. The supernatant collected and ammonium sulfate added at 4° C. with stirring until a concentration of 40 percent ammonium sulfate saturation was obtained. The solution was then centrifuged for 30 minutes at 16,000×g, the supernatant collected and ammonium sulfate added at 4° C. with stirring until the ammonium sulfate saturation was raised to 65 percent. The solution was then centrifuged for 30 minutes at 16,000×g and the resulting pellet resuspended in Tris buffer (100 mM, pH 7.6), containing 2 mM EDTA (Buffer A). This solution was desalted using Centriprep™ tubes (Amicon). Further purification was achieved by FPLC at room temperature.
C. Anion exchange chromatography
Anion exchange chromatography was performed on a Mono Q™ column 10/10 with about 150 mg of protein loaded on the column in each run. The sample was eluted with a gradient of 1M NaCl in 200 mL of buffer A. Fractions (4 mL) containing protein were detected by absorbance at 280 nm, the active fractions pooled and the buffer exchanged with the initial buffer of the chromatofocusing using Centriprep tubes.
D. Chromatofocusing
Chromatofocusing was performed on a Mono P™ column 5/20 using two different pH gradients: 6 to 4 and 5.5 to 4.5. For the gradient from pH 6 to pH 4, the initial buffer was Bis-Tris (25 mM, adjusted to pH 6.3 with HCl). The elution buffer was Polybuffer 7-4 (adjusted to pH 4 with HCl), diluted by a factor of ten with distilled water. For the gradient from pH 5.5 to pH 4.5, the initial buffer was piperazine (25 mM, pH 6.3, and the elution buffer was prepared as before with a final pH of 4.5. In both cases, before loading the sample, a pregradient was made by washing the column with 3 mL of the elution buffer. The separation was optimized by loading 100 μg of protein in a total volume of 100 μL. To scale up the process, 15 mg of protein were applied in each run, and the protein fractions (0.5 mL each) were monitored by absorbance at 280 nm.
E. Determination of enzyme purity
Fractions obtained from different columns were analyzed by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and isoelectrofocusing (IEF). For SDS-PAGE, preformulated gels were used with a gradient (from 8 to 25 percent) of polyacrylamide in the separating zone. Prior to electrophoresis, the samples were boiled at 100° C. for 3 minutes in a solution containing 0.5 percent sodium dodecyl sulfate and 5 percent 2-mercaptoethanol. The IEF was performed on preformulated gels with a pH range from 4.5 to 6.5. In both cases, the markers used were from Pharmacia. The gels were stained using the Pharmacia PhastSilver™ Kit, modified to provide higher sensitivity. This technique can detect proteins in the range of 0.1 to 0.05 ng of protein per band Heukeshoven et al., at Electrophoresis, 9:28 (1988)!.
F. Enzymatic assay
DERA activity was assayed with a coupled enzymatic system where 0.5 mM of 2-deoxyribose-5-phosphate, 0.12 mM NADH, and a mixture of glycerophosphate dehydrogenase and triose phosphate isomerase were incubated in triethanolamine buffer (50 mM, pH 7.5) at 25° C. The assay was initiated by addition of DERA, and the decrease in the absorbance at 340 nm was monitored. The extinction coefficient for NADH was taken as 6.22×10 3 M -1 cm -1 . Protein concentration was measured by the Bradford assay using the Coomasie Plus Kit Reagent from Pierce Co., instead of the method described previously Bradford, Anal. Biochem, 72:248 (1976) (describing the Bradford assay); Barbas et al., J. Am. Chem. Soc., 112:2013 (1990) (describing the previous method); Chen et al., J. Am. Chem. Soc., 114:741 (1992) (describing the previous method)!.
EXAMPLE 2
DERA-catalyzed Synthesis of 2-deoxy-L-fucose (Compound 2a)
The acceptor aldehyde (2S,3R)-dihydroxybutyraldehyde (Compound 1a) was obtained by the Sharpless asymmetric dihydroxylation of butyraldehyde. Henderson et al., J. Am. Chem. Sox., 116:58 (1994). Compound 1a (41.3 mg, 0.40 mmol) and acetaldehyde (52.8 mg, 1.2 mmol) were dissolved in 1 mM Tris and 0.01 mM EDTA buffer (4 mL, pH 7.3), and 160 units of DERA were added. The resulting solution was stirred in the dark for two days under nitrogen atmosphere. The reaction was quenched by addition of two volumes of acetone, cooling to 0° C. for 20 minutes, and centripred to remove the precipitated protein. The solvent was removed under reduced pressure. The product, 2-deoxyfucose (also known as 2,6-dideoxy-L-lyxo-hexose, Compound 2a), (36 mg, 51 percent) was purified by silica gel column chromatography (10:2, CHCl 3 /MeOH). The 1 H NMR spectra was identical to that reported in the literature. DeBruyn et al., Acta Chem. Scand., Ser. B B30(9) :820(1976).
EXAMPLE 3
Use of DERA to prepare 2-Deoxy-5-phenyl-L-lyxo-pentose (Compound 2b)
The enzyme, DERA was obtained as described in Example 1. The sharpless asymmetric dihydroxylation method was used to prepare 3-(3-phenyl-1R,2S-dihydroxypropyl-1,5-dihydro-3H-2,4-benzodioxepine. Henderson, et al, J. Am. Chem. Soc., 116:558(1994).
A solution of 3-(3-phenyl-1R,2S-dihydroxypropyl)-1,5-dihydro-3H-2,4-benzodioxepine (200 mg, 0.70 mmol) in 0.1N HCl (7 mL) was heated at 70° C. for three hours to form 3-phenyl-2S,3R)-dihydroxypropionaldehyde (Compound 1b). The solution was cooled to room temperature and the pH adjusted to 7.5. Acetaldehyde (0.12 mL, 2.1 mmol) and DERA (280 Units) were added and the solution maintained at 25° C. in the dark for two days. Purification by silicagel column chromatography (CHCl 3 /MeOH, 2:1) afforded Compound 2b (67 mg, 46 percent yield) as a thick oil. 1 H NMR (400 MHz, CD 3 OD) δ 1.36 (dd, J=4.9, 15.1 Hz, 1H), 1.45 (dd, J=5.2, 15.1 Hz, 1H), 3.40 (m, 1H), 3.58 (d, J=5.0 Hz, 1H), 3.71 (dd, J=4.0, 5.2 Hz, 1H), 5.10 (d, J=3.1 Hz, 1H), 7.27-7.44 (m, 5H); 13 C NMR (100 MHz, CD 3 OD) δ 40.35, 62.90, 73.50, 73.94, 106.65, 127.80, 128.17, 128.54, 128.63, 129.15, 140.81; HRMS for C 11 H 14 O 4 (M+Na + ), calculated to be 233.0790, and found to be 233.0779.
EXAMPLE 4
Use of DERA to Prepare 2-Deoxy-5-thio-D-erythro-pentose (Compound 4)
The acceptor aldehyde, 3-thioglyceraldehyde (Compound 3), was prepared by the method of Effenberger. Effenberger Tetrahedron Lett., 33:5157 (1992)!. DERA (400U) was added to a 10 mL solution containing the acceptor aldehyde (100 mM Compound 3) and donor aldehyde (300 mM acetaldehyde), triethanolamine buffer (100 mM, pH 7.3) and EDTA (1 mM). This reaction is shown in Scheme 1. The resulting solution was stirred in the dark for 2 days under a N 2 atmosphere. The reaction was quenched by addition of 2 volumes of acetone and cooling to 0° C. for 20 minutes. The precipitated protein was removed by centrifugation. After removal of the solvent under reduced pressure, a 33 percent yield of Compound 4 was obtained (characterized as 2-deoxy-5-thio-1,3,4-tri-O-acetyl-D-erythro-pentose). Compound 4 was purified from the residue by preparative TLC on silica (methanol/chloroform/hexane, 1:90:10).
The α-anomer was obtained in 15 percent yield (41 mg,R f =0.27). 1 H NMR (500 MHz, CDCl 3 ) δ 2.06 (s, 3H), 2.09 (s, 3H), 2.13 (s, 3H), 2.29 (ddd, J=2.8, 3.8, 15.4 Hz, 1H), 2.50 (dd, J=3.8, 12.8 Hz, 1H), 2.63 (ddd, J=3.2, 4.4, 15.4 Hz, 1H), 3.36 (dd, J=11.1, 12.8 Hz, 1H), 5.12 (ddd, J=2.6, 3.9, 11.1 Hz, 1H) 5.22-5.25 (m, 1H), 5.79 (t, J=3.5 Hz, 1H); 13 C NMR (125 MHz, CDCl 3 ) δ 20.87, 20.97, 21.09, 22.73, 35.87, 67.39, 68.84, 70.18, 169.25, 169.83, 170.09; HRMS for C 11 H 16 O 6 S (M+Na + ), calculated 299.0565, found 299.0565.
The β-anomer was obtained in 18 percent yield (50 mg, R f =0.36). 1 H NMR (500 MHz, CDCl 3 ) δ 2.05 (s, 3H), 2.12 (s, 3H), 2.08-2.15 (m, 1H), 2.16 (s, 3H), 2.44 (ddd, J=2.9, 11.3, 13.6 Hz, 1H), 2.87 (dd, J=1.6, 14.6 Hz, 1H), 3.26 (dd, J=1.9, 14.6 Hz, 1H), 5.21 (ddd, J=3.8, 3.8, 11.3 Hz, 1H), 5.34 (ddd, J=1.6, 1.9, 3.8 Hz, 1H), 6.03 (br s, 1H); 13 C NMR (125 MHz, CDCL 3 ) δ 21.0, 21.1, 21.2, 28.4, 32.5, 66.1, 67.3, 72.4, 169.4, 170.1, 170.4; HRMS for C 11 H 16 O 6 S (M+Na + ), calculated 299.0565, found 299.0577.
General Procedure for DERA-catalyzed multiple reactions
DERA (1000U) was added to a 20 ml. solution containing 100 mM of acceptor aldehyde and 300 mM of donor aldehyde, 100 mM triethanolamine buffer (pH 7.3) and 1 mM EDTA. The resulting solution was stirred in the dark for 6 days under N 2 . The reaction was quenched by addition of 2 volumes of acetone, then cooled to 0° C. for 20 minutes and centrifuged to remove the precipitated protein. After removal of the solvent under reduced pressure, the residue was purified by silica gel chromatography.
EXAMPLE 5
Use of DERA to Prepare 2,4,6-Trideoxy-D-erythro-hexose (Compound 5)
The reaction was performed according to the general procedure for multiple reactions using DERA, as described above, where both the donor and acceptor aldehydes were acetaldehyde. The crude product was purified by flash chromatography (silica, ethyl acetate) to give Compound 5 (60 mg, 22 percent yield) as a mixture of anomers (α:β ratio in D 2 O 1:8).
1 H NMR (400 MHz, CDCl 3 ) δ 1.21 (d, J=6.3 Hz, 3H, α), 1.23 (d, J=6.3 Hz, 3H, β), 1.42-2.00 (m, 4H), 3.09 (d, J=6.2 Hz, 1H, α), 3.43 (d, J=5.1 Hz, 1H, β), 4.07 (ddq, J=2.2, 6.3, 11.4 Hz, 1H, β), 4, 17 (s, 1H), 4.18 (s, 1H), 4.18-4.24 (m, 1H, α), 4.32 (dq, J=2.7, 5.4 Hz, 1H, β), 4.42 (ddq, J=2.3, 6.3, 11.8 Hz, 1H, α), 5.16 (br d, J=10.2 Hz, 1H, β), 5.32 (t, J=4.8 Hz, 1H, α); α-anomer: 13 C NMR (100 MHz, CDCl 3 ) δ 21.43, 34.90, 39.86, 59.00, 65.02, 92.25; β-anomer: 13 C NMR (CDCl 3 ) δ 21.31, 39.42, 39.55, 65.59, 66.57, 92. HRMS for C 6 H 12 O 3 (M+Na + ), calculated 155.0684, found 155.0684.
EXAMPLE 6
Use of DERA to Prepare 6-O-Methyl-2,4-dideoxy-D-erythro-hexose (Compound 6)
The reaction was performed according to the general procedure for multiple reactions using DERA, as described above, where the acceptor aldehyde was 2-methoxyacetaldehyde and the donor aldehyde was acetaldehyde. The crude product was purified by flash chromatography (silica, ethyl acetate to ethyl acetate/methanol 12:1) to give Compound 6 (211 mg, 65 percent yield) as a mixture of anomers (α:β ratio in D 2 O 1:7).
1 H NMR (400 MHz, CDCl 3 ) δ 1.45-1.97 (m, 4H), 3.35 (s, 3H, β), 3.36 (s, 3H, α), 3.35-3.46 (m, 2H), 4.08-4.15 (m, 1H, β), 4.17-4.20 (m, 1H, α), 4.28-4.32 (m, 1H, β), 4.42-4.49 (m, 1H, α), 5.14 (dd, J=2.2, 9.8 Hz, 1H, β), 5.34 (d, J=3.3 Hz, 1H, α) ; α-anomer: 13 C NMR (100 MHz, CDCl 3 ) δ 34.11, 34.81, 59.08, 62.23, 64.35, 75.54, 92.14; β-anomer: 13 C NMR (100 MHz, CDCl 3 ) δ 33.83, 39.30, 59.05, 64.88, 69.51, 75.76, 92.70; HRMS for C 7 H 14 O 4 (M+Na + ), calculated 185.0790, found 185.0796.
EXAMPLE 7
Use of DERA to Prepare 6-Chloro-2,4,6-trideoxy-D-erythro-hexose (Compound 7)
The reaction was performed according to the general procedure for multiple reactions using DERA, described above, where the acceptor aldehyde was 2-chloroacetaldehyde and the donor aldehyde was acetaldehyde. The crude product was purified by flash chromatography (silica, ethyl acetate/hexane from 2:1 to 3:1) to give Compound 7 (235 mg, 70 percent yield) as a mixture of anomers (α:β ratio in D 2 O 1:6).
1 H NMR (400 MHz, CDCl 3 ) δ 1.53-2.00 (m, 4H) 3.52-3.62 (m, 2H), 4.12-4.18 (m, 1H, β), 4.23-4.28 (m, 1H, α), 4.34-4.38 (m, 1H, β), 4.45-4.52 (m, 1H, α), 5.20 (dd, J=2.1, 9.5 Hz, 1H, β), 5.37 (br t, J=4.1 Hz, 1H, α) ; α-anomer: 13 C NMR (100 MHz, CDCl 3 ) δ 35.07, 39.23, 47.03, 63.24, 64.89, 92.54; β-anomer: 13 C NMR (100 MHz, CDCl 3 ) δ 34.74, 35.35, 47.75, 64.49, 70.50, 93.03; HRMS for C 6 H 11 O 3 Cl (M+Na + ), calculated 189.0294, found 189.0288.
EXAMPLE 8
Use of DERA to prepare 6-Azido-2,4,6-trideoxy-D-erythro-hexose (Compound 8)
The reaction was performed according to the general procedure for multiple reactions using DERA, as described above, where the acceptor aldehyde was 2-azidoacetaldehyde and the donor aldehyde was acetaldehyde. The crude product was purified by flash chromatography (silica, ethyl acetate/hexane from 1:1 to 2:1) to give Compound 8 (81 mg, 23 percent yield) as a mixture of anomers (α:β ratio 2:3).
1 H NMR (400 MHz, D 2 O) δ 1.54-1.98 (m, 4H), 3.37-3.51 (m, 2H), 4.09-4.16 (m, 1H, β), 4.42-4.27 (m, 1H, α), 4.35-4.39 (m, 1H, β), 4.41-4.48 (m, 1H, α), 5.15 (dd, J=2.0, 10.0 Hz, 1H, β), 5.31 (br t, J=2.2 Hz, 1H, α); α-anomer: 13 C NMR (100 MHz, D 2 O) δ 36.02, 37.64, 56.49, 65.61, 66.44, 94.01; β-anomer: 13 C NMR (100 MHz, D 2 O) δ 35.94, 40.46, 56.69, 66.98, 72.55, 94.44; HRMS for C 6 H 11 O 3 N 3 (M+Na + ), calculated 196.0698, found 196.0706.
The foregoing description and the examples are intended as illustrative and are not to be taken as limiting. Still other variations within the spirit and scope of this invention are possible and will readily present themselves to those skilled in the art.
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Processes using 2-deoxyribose-5-phosphate aldolase (DERA) are described for the preparation of 2-deoxyfucose and related compounds. In one embodiment, DERA is used to catalyze the condensation of acetaldehyde as donor and a 2(R)-hydroxy-3-(hydroxy or mercapto)-propionaldehyde derivative to form a 2-deoxysugar whose hydroxyls have the configuration of fucose. In another embodiment, DERA is used to catalyze the condensation of two moles of acetaldehyde as donor and one mole of a 2-substituted acetaldehyde acceptor to form a 2,4,6-trideoxyhexose via a 4-substituted-3-hydroxybutanal intermediate.
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This is a divisional of application Ser. No. 09/817,694, filed Mar. 26, 2001 now abandoned, which claims priority from provisional application Ser. No. 60/193,615, filed Mar. 31, 2000.
FIELD OF THE INVENTION
The present invention is related in general to the field of semiconductor devices and processes and more specifically to a fixture and process for electroless plating bondable metal caps onto bond pads of integrated circuits having copper interconnecting metallization.
DESCRIPTION OF THE RELATED ART
In integrated circuits (IC) technology, pure or doped aluminum has been the metallization of choice for interconnection and bond pads for more than four decades. Main advantages of aluminum include ease of deposition and patterning. Further, the technology of bonding wires made of gold, copper, or aluminum to the aluminum bond pads has been developed to a high level of automation, miniaturization, and reliability. Examples of the high technical standard of wire bonding to aluminum can be found in U.S. Pat. No. 5,455,195, issued on Oct. 3, 1995 (Ramsey et al., “Method for Obtaining Metallurgical Stability in Integrated Circuit Conductive Bonds”); U.S. Pat. No. 5,244,140, issued on Sep. 14, 1993 (Ramsey et al., “Ultrasonic Bonding Process Beyond 125 kHz”); U.S. Pat. No. 5,201,454, issued on Apr. 13, 1993 (Alfaro et al., “Process for Enhanced Intermetallic Growth in IC Interconnections”); and U.S. Pat. No. 5,023,697, issued on Jun. 11, 1991 (Tsumura, “Semiconductor Device with Copper Wire Ball Bonding”).
In the continuing trend to miniaturize the ICs, the RC time constant of the interconnection between active circuit elements increasingly dominates the achievable IC speed-power product. Consequently, the relatively high resistivity of the interconnecting aluminum now appears inferior to the lower resistivity of metals such as copper. Further, the pronounced sensitivity of aluminum to electromigration is becoming a serious obstacle. Consequently, there is now a strong drive in the semiconductor industry to employ copper as the preferred interconnecting metal, based on its higher electrical conductivity and lower electromigration sensitivity. From the standpoint of the mature aluminum interconnection technology, however, this shift to copper is a significant technological challenge.
Copper has to be shielded from diffusing into the silicon base material of the ICs in order to protect the circuits from the carrier lifetime killing characteristic of copper atoms positioned in the silicon lattice. For bond pads made of copper, the formation of thin copper (I) oxide films during the manufacturing process flow has to be prevented, since these films severely inhibit reliable attachment of bonding wires, especially for conventional gold-wire ball bonding. In contrast to aluminum oxide films overlying metallic aluminum, copper oxide films overlying metallic copper cannot easily be broken by a combination of thermocompression and ultrasonic energy applied in the bonding process. As further difficulty, bare copper bond pads are susceptible to corrosion.
In order to overcome these problems, a process has been disclosed to cap the clean copper bond pad with a layer of aluminum and thus re-construct the traditional situation of an aluminum pad to be bonded by conventional gold-wire ball bonding. A suitable bonding process is described in U.S. Pat. No. 5,785,236, issued on Jul. 28, 1998 (Cheung et al., “Advanced Copper Interconnect System that is Compatible with Existing IC Wire Bonding Technology”). The described approach, however, has several shortcomings.
First, the fabrication cost of the aluminum cap is higher than desired, since the process requires additional steps for depositing metal, patterning, etching, and cleaning. Second, the cap must be thick enough to prevent copper from diffusing through the cap metal and possibly poisoning the IC transistors. Third, the aluminum used for the cap is soft and thus gets severely damaged by the markings of the multiprobe contacts in electrical testing. This damage, in turn, becomes so dominant in the ever decreasing size of the bond pads that the subsequent ball bond attachment is no longer reliable.
A low-cost structure and method for capping the copper bond pads of copper-metallized ICs has been disclosed on U.S. patent application No. 60/183,405, filed on 18 Feb. 2000. The present invention is related to that application. The structure provides a metal layer plated onto the copper, which impedes the up-diffusion of copper. Of several possibilities, nickel is a preferred choice. This layer is topped by a bondable metal layer, which also impedes the up-diffusion of the barrier metal. Of several possibilities, gold is a preferred choice. Metallurgical connections can then be performed by conventional wire bonding.
It is difficult, though, to plate these bond pad caps uniformly in electroless deposition systems, because electroless deposition is affected by local reactant concentrations and by the agitation velocities of the aqueous solution. Deposition depletes the reactants in areas around the bond pads. Increasing the agitation of the solution only exacerbates the deposition non-uniformity, which is influenced by the flow direction of the solution. The problem is further complicated when a whole batch of wafers is to be placed simultaneously in order to reduce cost, since known control methods have been applied only to process single wafers under applied electrical bias. See, for example, U.S. Pat. No. 5,024,746, issued Jun. 18, 1991, and U.S. Pat. No. 4,931,149, issued Jun. 5, 1990 (Stierman et al., “Fixture and a Method for Plating Contact Bumps for Integrated Circuits”).
An urgent need has arisen for a reliable method of plating metal caps over copper bond pads which combines minimum fabrication cost with maximum plating control of all layers to be deposited. The plating method should be flexible enough to be applied for different IC product families and a wide spectrum of design and process variations. Preferably, these innovations should be accomplished while shortening production cycle time and increasing throughput, and without the need of expensive additional manufacturing equipment.
SUMMARY OF THE INVENTION
The present invention discloses a method and an apparatus for uniform electroless plating of layers onto exposed metallizations in integrated circuits such as bond pads. The apparatus provides means for holding a plurality of wafers, and rotating each wafer at constant speed and synchronous within the plurality. Immersed in a plating solution flowing in substantially laminar motion and at constant speed, the method creates periodic superposition relative of directions and speeds of the motion of the wafers and the motion of the plating solution. The invention creates periodically changing wafer portions where the directions and speeds are additive and where the directions and speeds are opposed and subtractive. Consequently, highly uniformly layers are electrolessly plated onto the exposed metallizations of bond pads. If the plated layers are bondable metals, the process transforms otherwise unbondable bond pad metallization into bondable pads.
The present invention is related to high density and high speed ICs with copper interconnecting metallization, especially those having high numbers of copper metallized inputs/outputs, or “bond pads”. These circuits can be found in many device families such as processors, digital and analog devices, logic devices, high frequency and high power devices, and in both large and small area chip categories.
It is an aspect of the present invention to be applicable to bond pad area reduction and thus to be in support of the shrinking of IC chips. Consequently, the invention helps to alleviate the space constraint of continually shrinking applications such as cellular communication, pagers, hard disk drives, laptop computers and medical instrumentation.
Another aspect of the invention is to deposit the bond pad metal caps by the self-defining process of electroless plating, thus avoiding costly photolithographic and alignment techniques.
Another aspect of the invention is to accomplish the control and stability needed for successful electroless metal deposition.
Another aspect of the invention is to advance the process and reliability of wafer-level multi-probing by eliminating probe marks and subsequent bonding difficulties.
Another object of the invention is to provide design and process concepts which are flexible so that they can be applied to many families of semiconductor products, and are general so that they can be applied to several generations of products.
Another object of the invention is to use only designs and processes most commonly employed and accepted in the fabrication of IC devices, thus avoiding the cost of new capital investment and using the installed fabrication equipment base.
These objects have been achieved by the teachings of the invention concerning selection criteria, process flows and controls suitable for mass production. Various modifications have been successfully employed to satisfy the requirements of different plating solutions.
In the first embodiment of the invention, an apparatus is disclosed for uniform electroless plating of layers onto exposed metallizations in integrated circuits, such as bond pads, which are positioned on the active surface of semiconductor wafers. The apparatus is suitable for simultaneous processing of a plurality of wafers. It provides rotation at constant speed synchronously to the wafers and thus creates relative motion, between the wafers and the chemical solution of a plating bath.
In the second embodiment of the invention, a plating apparatus is disclosed which combines the rotation of the wafers with the laminar motion at constant speed of the plating solution. The superposition of rotational and laminar motions and the resulting periodic changes of direction and speed create periodically changing wafer portions where the speeds are additive and where the speeds are subtractive. The resulting controlled electroless deposition of metal creates uniformly plated layers.
In all preferred embodiments, the various metal layers are deposited by electroless plating, thus avoiding the need for expensive photolithographic definition steps.
The technical advances represented by the invention, as well as the aspects thereof, will become apparent from the following description of the preferred embodiments of the invention, when considered in conjunction with the accompanying drawings and the novel features set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic side view of the first embodiment of the invention, the apparatus for controlled electroless plating including a plurality of integrated circuit wafers.
FIG. 2 is a schematic end view of the first embodiment of the invention, the apparatus for controlled electroless plating.
FIG. 3 is a schematic composite side view and cross section of the second embodiment of the invention, the plating tank and apparatus for controlled electroless plating.
FIG. 4 is a schematic composite end view and cross section of the second embodiment of the invention, the plating tank and apparatus for controlled electroless plating.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Illustrating the first embodiment of the invention, generally designated 100 , FIG. 1 shows a side view of the apparatus for controlled electroless plating of uniform metal layers onto exposed metallizations on a plurality of integrated circuit (IC) wafers 101 . Usually, there are 10 to 30 wafers in a batch. In the fixture 100 , the wafers 101 are held approximately parallel to each other at predetermined distances 102 . A typical distance is in the range from about 5 to 10 mm and thus several times wider than the thickness of a wafer (about 0.25 to 0.75 mm). At their rims, the wafers are loosely held in grooves 103 of rollers. In FIG. 1 , two rollers are shown, the bottom roller 105 and the capture roller 104 . The rollers are made of chemically inert plastic material such as polypropylene. Instead of grooved rollers, toothed rollers may be used. A practical groove is about 2 to 5 mm deep. In the preferred embodiments, there are three rollers (see FIG. 2 ) employed to contain the wafers.
It is an essential feature of the invention that the rollers can be set in rotational motion by their respective driven gears 104 a and 105 a, which are driven by a central sun gear 110 (partially obscured in FIG. 1 , but fully visible in FIG. 2 ). With this feature, the turning sun gear 110 drives all rollers at the same speed. Consequently, all wafers 101 , contained in the roller grooves 103 and held in secure contact with the roller material by their weight, are rotating in unison at constant speed and in synchronous manner. For wafers of 200 mm diameter, preferred rotation speeds are in the range of about 0.5 to 5 rpm.
In FIG. 2 , fixture 100 is displayed in a schematic end view. All three rollers are indicated by their respective driven gears 104 a , 105 a and 106 a . The position of a 200 mm IC wafer is indicated by dashed line 101 a . For practical ease of loading and unloading of the wafers, one of the rollers (in FIGS. 1 and 2 , the capture roller 104 ) has a handle 104 b fixed to a pivot arm 201 so that the roller 104 can be swung sidewise manually. In FIG. 2 , the closed position is indicated by solid lines for pivot arm 201 and driven gear 104 b , the opened position by dashed lines.
Illustrating the second embodiment of the invention, generally designated 300 , as well as the process for electroless plating, FIGS. 3 and 4 show schematically the cross section through a plating tank filled by the liquid plating solution 302 up to the surface 302 a of the solution. The plating tank has an outer wall 301 a and an inner wall 301 b , separated by a gap 303 , which enables the reflow of the liquid. In FIGS. 3 and 4 , arrows indicate the flow of the liquid solution. As can be seen, the solution enters the tank from the bottom (arrows 310 ), moves in laminar flow at constant speed upward (for example, at a speed of 20 cm/min) through the tank, and exits from the tank surface (arrows 311 ) by overflowing into the reflow gap 303 . After reaching the tank bottom, the flow cycle begins anew.
Further shown in FIGS. 3 and 4 is the apparatus/fixture for holding a plurality of wafers, explained in FIGS. 1 and 2 . In FIG. 3 , the fixture is illustrated in side view 320 as in FIG. 1 ; in FIG. 4 , the fixture is illustrated in end view 420 as in FIG. 2 . As can be seen from FIG. 3 , the fixture is loaded with a batch of wafers 321 , contained on their side edges while their active and passive surfaces covered by a protective resist are exposed to the plating solution (the passive surfaces are covered by a protective resist).
On its laminar flow from the bottom to the surface of the tank, the plating solution flows substantially parallel to the active surfaces of the wafers contained in the fixture. In order to control the electroless plating process and achieve uniform metal layer deposition, it is an essential feature of the present invention that the direction and speed of the laminarly moving solution is superposed by another relative motion. This additional relative motion is generated by the rotation at constant speed of the wafers held in the fixture (the fixture causes the wafers to move synchronously with each other). With this additional motion, a periodic superposition of directions and speeds is achieved between the motion of the wafers and the motion of the solution, resulting in periodically changing wafer portions where the directions and speeds are additive and where the directions and speeds are opposed and subtractive.
This periodic relative motion in changing directions between the plating solution and the rotating wafers is crucial for creating uniformly plated layers on exposed metallizations of the active wafer surfaces by controlled electroless deposition.
The preferred electroless process flow used for plating uniform metal layers as caps onto exposed copper metallizations such as bond pads of ICs positioned on the active surface of semiconductor wafers has the following steps. The example is chosen for fabricating a cap consisting of two metal layers.
Step 1: Coating the passive surface of the IC wafers with resist using a spin-on technique. This coat will prevent accidental metal deposition on the passive surface of the wafers. Step 2: Baking the resist, typically at 110° C. for a time period of about 30 toe 60 minutes. Step 3: Cleaning of the exposed bond pad copper surface using a plasma ashing process for about 2 minutes. Step 4: Loading the wafers into the apparatus/fixture described above for controlled electroless plating. Step 5: Cleaning by immersing the wafers, having the exposed copper of the bond pads, in a solution of sulfuric acid, nitric acid, or any other acid, for about 50 to 60 seconds. Step 6: Rinsing in overflow rinser for about 100 to 180 seconds. Step 7: Immersing the wafers in a catalytic metal chloride solution, such as palladium chloride, for about 40 to 80 seconds. This step “activates” the copper surface, i.e., a layer of seed metal (such as palladium) is deposited onto the clean non-oxidized copper surface. Step 8: Rinsing in dump rinser for about 100 to 180 seconds. Step 9: Initiating laminar motion at constant speed of first electroless plating solution in plating tank. If nickel is to be plated, the solution consists of an aqueous solution of a nickel salt, such as nickel chloride, sodium hypo-phosphite, buffers, complexors, accelerators, stabilizers moderators, and wetting agents. Step 10: Immersing the wafers into the electroless plating solution. The solution, flowing in laminar motion at constant speed, flows substantially parallel to the active surface of the wafers. Step 11: Initiating rotation of wafers at constant speed and synchronously with each other, initiating superposition of directions and speeds of the waver motion and the solution motion. Step 12: Plating layer electrolessly. If a nickel layer is to be plated, plating between 150 and 180 seconds will deposit about 0.4 to 0.6 μm thick nickel layer. Step 13: Stopping rotation of wafers. Step 14: Removing wafers from plating solution. Step 15: Rinsing in dump rinser for about 100 to 180 seconds. Step 16: Repeating Steps 9 through 15 for second electroless plating solution, varying composition of solution and plating time according to metal-to-be-plated. Step 17: Repeating Steps 9 through 15 for third electroless plating solution, varying composition of solution and plating time according to metal-to-be-plated. Step 18: Stripping wafer protection resist from passive surface of wafers for about 8 to 12 minutes. Step 19: Spin rinsing and drying for about 6 to 8 minutes.
While this invention has been described in reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description. As an example, the invention can be applied to IC bond pad metallizations other than copper, which are difficult or impossible to bond by conventional ball or wedge bonding techniques, such as alloys of refractory metals and noble metals. As another example, the invention applies to immersion plating and autocatalytic plating. A sequence of these plating techniques is particularly useful for electroless plating of gold layers. As another example, the invention provides for easy control of the uniformity of plated layers by modifying individually the flow speed of the plating solution or the rotation speed of the wafers, even in the course of one plating deposition. It is therefore intended that the appended claims encompass any such modifications or embodiments.
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A method and an apparatus for uniform electroless plating of layers onto exposed metallizations in integrated circuits such as bond pads. The apparatus provides means for holding a plurality of wafers, and rotating each wafer at constant speed and synchronous within the plurality. Immersed in a plating solution flowing in substantially laminar motion and at constant speed, the method creates periodic superposition of directions and speeds of the motion of the wafers and the motion of the plating solution. The invention creates periodically changing wafer portions where the directions and speeds are additive and where the directions and speeds are opposed and subtractive. Consequently, highly uniformly layers are electrolessly plated onto the exposed metallizations of bond pads. If the plated layers are bondable metals, the process transforms otherwise unbondable pad metallization into bondable pads.
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CROSS REFERENCE TO RELATED APPLICATION
This application represents the U.S. National Stage Filing under 35 U.S.C. §371 of International Application No. PCT/CA2005/001398, filed Sep. 14, 2005, which was published in English, designated/elected the United States of America, and claims priority to International Application No. PCT/CA2004/001676 filed on Sep. 14, 2004 and to U.S. Provisional Patent Application No. 60/614,556, filed Oct. 1, 2004, all of which are incorporated by reference into the present application in their entirety for all purposes.
FIELD OF THE INVENTION
The present invention relates to a novel process for isolating growth and differentiating factors from colostrum. This process is characterized by maturation steps (controlled mild acid hydrolysis) and physical steps (molecular filtration). The invention further includes the use of the growth and differentiating factors derived from this process in prophylactic, therapeutic, cosmetic, cosmeceutical, dermatological, pharmaceutical, medical, veterinary or surgical (burn wounds, wounds, etc.) applications.
BACKGROUND OF THE INVENTION
Colostrum is a thick, yellow fluid produced by mammary glands during the first few days after birth. It provides life-supporting immune (gamma globulin) and growth factors that ensure the health and vitality of a newborn.
The identities and functions of many of the bioactive principles of colostrum milk remain to be elucidated. However, colostrum is known to be a source of numerous bioactive hormones and growth factors, many of which have been demonstrated to influence intestinal growth, cell differentiation, and the development of the immune and enteroendocrine systems when administered in isolation.
Growth factors may be defined as proteins of 5 to 680 kDa that possess growth modulating bioactivities. Their biological actions also include the modulation and facilitation of the expression of cellular phenotype. To exert biological effects, growth factors must interact with specific high-affinity membrane receptors that activate appropriate signal transduction/second messenger cascades.
In their natural state, most growth factors are inert on human cells and have very high molecular weights (340-580 kDa). In order to become active, these growth factors need to be released from their inactive original forms either through hydrolysis or temperature change, or both.
Interestingly, even growth factors from non-human origin, such as those derived from porcine or bovine colostrum, when converted into their active forms, have been found to be active on human cells. This can be explained by the fact that the active forms of smaller molecular weight are almost completely homologous to the corresponding human growth factors. This has been found to be the case, for example, for the following families of factors: IGFs (1-3), TFGs β (1-3), PDGFs (AA, AB, BB), BMPs (1-24) and FGFs (1-16). These factors, when in active form, are recognized for their ability to proliferate and/or differentiate the stem cells of a newborn.
U.S. Pat. No. 6,277,813 (Kelly) describes the extraction of a novel growth factor from porcine colostrum. The process for extracting this growth factor, identified as CDGF for “Colostrum Derived Growth Factor”, includes the following steps: (1) separating all components of colostrum having a molecular weight below 200 kDa and discarding all components having a lower molecular weight; (2) treating the product of step 1 with dithiothreitol and boiling for 10 minutes; and (3) centrifuging the mixture of step (2) to spin down any precipitated matter and recovering the CDGF located in the supernatant.
U.S. Pat. No. 5,500,229 (Aalto et al.) discloses a colostral fraction having a low endotoxin, protein and immunoglobulin concentration. The colostral fraction is obtained through ultrafiltration of defatted colostrum using a membrane having a molecular weight cut off of 100 kDa and is intended for use as a supplement in cell culture media. The colostral fraction is said to be extremely useful either alone or when complemented by other supplements for replacing partially or completely fetal bovine serum in widely used cell culture media. The patent describes the effectiveness of the colostral fraction in the cultivation of hybridoma cells. (This invention is also described in Appl Microbiol Biotechnol (1992) 37: 451-456.)
European Patent No. 918464 (Adler et al.) discloses a process for preparing a colostral milk product from which casein has been largely removed and the colostrum has been defatted. The defatted and largely decaseinated colostrum is passed through an ultrafiltration column with an exclusion molecular mass of approximately 10 6 . The product obtained can be further filtered using columns with exclusion molecular masses of 300 kDa and/or 150 kDa and/or 50 kDa and/or 30 kDa and/or 20 kDa and/or 10 kDa and/or 5 kDa and/or 1 kDa and/or 0.5 kDa. The resulting products are said to be suitable for use as an additive for drugs, food supplements, beverages, baby food, animal food, beverages in intensive sport for muscle protection or for reducing the muscular recovery phase, and for the prevention and treatment of bacterial, viral and mycotic infections.
Chinese Patent No. 1557837 (Gao Chunping) describes a process to separate insulin-like growth factor, immunoglobulins and casein from bovine colostrum. Colostrum is defatted and acidified to separate the insulin-like growth factor from binding, and the insulin-like growth factor is isolated through ultrafiltration, concentrated and freeze dried to obtain a powder. Immunoglobulins are separated through ultrafiltration and concentrated to prepare a powdered product. Casein is obtained through ultrafiltration or pH regulation, heat solidified and reacted with hydrolase to prepare casein phosphate polypeptide. The process is said to greatly lower production costs.
Chinese Patent No. 1557340 (also to Gao Chunping) describes a method of preparing a high bioreactivity growth factor and immunoglobulin from bovine colostrum. The method involves collecting colostrum 72 hours after parturition, defatting the colostrum through centrifugation, acidifying the solution, heating to solidify casein, centrifugally filtering or filtering the solution with cloth to eliminate casein, diluting the resulting solution, collecting the supernatant, concentrating with low molecular weight ultrafiltration membranes, and processing further in order to produce a dry powder preparation, a spray preparation, and the like. The product is intended for use in the treatment of various bacterial and viral infections.
U.S. Pat. No. 6,875,459 (Kopf et al.) discloses a method and apparatus for separation of milk, colostrum and whey components. In a preferred embodiment, the apparatus and method employ cross-flow filtration, chromatography and fermentation to separate the components of milk, colostrum and whey. The apparatus and method allow the extraction of immunoglobulins, among other factors.
European Patent No. 711171 (Laato et al.) describes a method for the improvement of wound healing in mammals, including humans, by using a colostral fraction. The colostral fraction is prepared by subjecting colostrum, from which part of the fat and cellular debris have been removed by conventional methods such as centrifugation, to ultrafiltration by using a membrane having a cutoff of 100 kDa and recovering the filtrate. The method for promoting wound healing consists of administering the colostral fraction locally.
PCT Publication No. WO 9811910 describes the use of a composition containing at least one compound with Growth Factor-like activity for the prevention or treatment of a gastrointestinal condition that is characterized at least partially by damage to epithelial cells and caused by the administration of a non-steroidal anti-inflammatory drug. Compositions for use in the invention may contain an IGF (e.g. IGF-1 or 2), a transforming growth factor (e.g. TGF1, TGF2 or TGF3), a keratinocyte growth factor, a fibroblast growth factor and/or a platelet-derived growth factor. The compositions containing the TGFs are preferably, though not exclusively, derived from colostrum. Similarly, PCT Publication No. WO 9811904 describes the use of colostrum or a derivative thereof for the prevention or treatment of a gastrointestinal condition that is characterized at least partially by damage to epithelial cells and caused by the administration of a non-steroidal anti-inflammatory drug. Derivatives suitable for use include ultrafiltered or microfiltered fractions of colostral whey (colostrum from which casein proteins have been removed), which are said to contain more concentrated Growth Factors relative to remaining colostral proteins and nutrients. Colostral whey may be used in liquid form (which may be defatted if desired) or may be further treated (such as being spray dried).
Other methods for the extraction of growth factors are known in the art, but surprisingly, no process appear to exist for deliberately and simultaneously isolating growth factors with highly disparate molecular weights. In addition, a number of methods rely on temperature conditions that have the effect of destroying the activity of the growth factors that are sought to be extracted.
There is therefore a need for a method of isolating growth and differentiating factors from colostrum that permits the separation of a great number of these factors (or “pools” of factors) in a manner that is efficient, reproducible and non-deleterious to their activities.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a novel process for isolating growth and differentiating factors from colostrum. More specifically, this process is characterized by maturation steps (controlled mild acid hydrolysis) and physical steps (molecular filtration) which optimize recovery of measured growth factors and their ability to entice a response on human cells.
In contrast to processes that are known in the art, the process of the present invention is neither performed at boiling temperatures. What results from this process are novel filtrate “pools” containing factors that are active on human cells, even if the colostrum is of bovine origin.
In one preferred embodiment, the process includes:
Diluting the colostrum and subjecting it to partial hydrolysis by adjusting the pH to about 3.75-3.85; vortexing the resulting colostral solution 60 minutes (30-90 minutes); adjusting the pH of the colostral solution to about 4.52-4.55; centrifuging the new colostral solution, and setting aside the resulting supernatant; and running the supernatant through a filtration system comprising one or more filtration columns (ceramic membranes) in order to obtain a fraction containing pools of growth and differentiating factors,
all the while ensuring that the reaction temperature never exceeds 38° C.
In another embodiment, the process further comprises lyophilizing the pools of derived growth and differentiating factors.
Generally, the process includes a filtration system which is comprised of one or more filtration columns selected from the following filtration sizes: 0.2 μm, 300 kDa, 150 kDa, 50 kDa, 15 kDa and 5 kDa. More specifically, and depending on the content and concentration of pooled growth and differentiating growth factors that are sought, the filtration system is selected from one of the following: a 0.2 μm column; a 300 kDa column; a 150 kDa column; a 50 kDa column; a 15 kDa column; a 0.2 μm column linked with a 150 kDa column; a 0.2 μm column linked with a 15 kDa column; and a 150 kDa column linked with a 15 kDa column.
The invention further includes colostral fractions isolated from the process of the present invention. Such fractions may include one or more fractions selected from the following: LP1, LP2, LP3, LP4, LP5, LP1-LP3, LP1-LP5 and LP3-LP5 (see the compositions of these fractions in Table 5). Depending on the application, these fractions may be used in their native form or they may be combined with an excipient or carrier.
Advantageously, this process allows the derivation and isolation of growth and differentiating factors, with the result that a number of factors with highly disparate sizes (or molecular weights) can be separated in pools from one another and used in select and varied ways, such as in cosmetic, cosmeceutical, nutraceutical, dermatological, pharmaceutical, medical and veterinary applications.
Other objects, advantages and features of the present invention will become apparent upon reading of the following non restrictive description of preferred embodiments thereof, given by way of example only with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 : Schematic view of the process steps for the isolation of growth factors from colostrum, including (A) controlled mild acid hydrolysis and (B) molecular filtration.
FIG. 2 : Growth factors found in colostral fractions.
FIG. 3 : Human ELISA test results for growth factors found in colostral fractions.
FIG. 4 : Fibroblast growth (Hoechst) during 72 hr exposure.
FIG. 5 : Fibroblast growth (new pools, Hoechst) during 72 hr exposure.
FIG. 6 : Proliferation of Human Umbilical Vein Endothelial Cells (HUVECs) (Cyquant®).
FIG. 7 : Percent of proline integrated into collagen synthesis.
FIG. 8 : Collagen Synthesis and Deposition in monolayer cell cultures as a function of cell number.
FIG. 9 : Collagen synthesis and deposition by fibroblasts in fibrin gel (new LP pools).
FIG. 10 : Fibroblasts grown in fibrin gel for 7-9 days. In the presence of 3.3 mg/ml LP1-LP3, fibroblasts formed a dense matrix as observed on phase contrast (A) whereas the cell density was limited as observed after Hoescht staining (B). Conversely, the control culture in serum-free resulted in poor matrix density (C&D), compared to A & B. At day 8, fibroblast-containing fibrin gels were released from the culture wells and observed the next day for potential contraction as observed in the presence of 3.3 mg/ml LP1-LP3 (E) compared to control culture (F). In the presence of LP1-LP5, at 1 mg/ml, fibroblasts reorganized into a network as observed by phase contrast (G) and at 3.3 mg/ml fibrin liquefied and aggregated (H). Magnification at 20×.
FIG. 11 : Human fibroblast proliferation assay (Cyquant®); 0.33 mg/ml, 1 mg/ml and 3.30 mg/ml of growth factor pools LP1-LP3, LP1-LP5 and LP3-LP5 were tested.
FIG. 12 : Effect on chondrocyte proliferation of 1 mg/ml and 3 mg/ml LP1-LP5 incubated 3 days.
FIG. 13 : Effect on chondrocyte proliferation of 1 mg/ml and 3 mg/ml LP1-LP5 incubated 7 days.
FIG. 14 : Effect on chondrocyte proliferation of 1 mg/ml and 3 mg/ml LP1-LP5 incubated 10 days.
FIG. 15 : Average number of chondrocytes treated with LP1-LP5 over three different periods of time.
FIG. 16 : Epidermal covering (epidermization) at day 7 due to LP1-LP3, LP1-LP5 and LP3-LP5.
FIG. 17 : Diminution of wound areas (granulation tissue) caused by LP1-LP3, LP1-LP5 and LP3-LP5 after 7 days, 14 days and 28 days.
FIG. 18 : Wound (dermal) thickness 5 after 7 days and 14 days resulting from LP1-LP3, LP1-LP5 and LP3-LP5.
FIG. 19 : Formation of collagen fibers due to LP1-LP3, LP1-LP5 and LP3-LP5 after 7 days, 14 days and 28 days.
FIG. 20 : Ratio of epidermization for fractions LP1 and LP1-LP3, and LP1-LP5, after 5, 7 and 10 days.
FIG. 21 : Specific activity of alkaline phosphatase at days 0, 6 and 12 for brush cells exposed to LP1, LP1-LP3, LP1-LP5 and LP3-LP5.
FIG. 22 : Specific activity of sucrase at days 0, 6 and 12 for brush cells exposed to LP1, LP1-LP3, LP1-LP5 and LP3-LP5.
FIG. 23 : Specific activity of lactase at days 0, 6 and 12 for brush cells exposed to LP1, LP1-LP3, LP1-LP5 and LP3-LP5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Definitions: 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 invention belongs.
“Cosmeceutical”: A cosmetic product claimed to have medicinal or drug-like benefits. Cosmeceutical products are marketed as cosmetics, but reputedly contain biologically active ingredients. Examples include anti-wrinkle skin creams with ingredients such as alpha lipoic acid and dimethylaminoethanol.
“Brush cell”: A brush cell has rootlet like projections as a tuft that form squat microvilli with filaments that stretch into the cell's cytoplasm; about 120-140 microvilli may be found on each cell, and the cell has a skewed or tilted position in tissue sections. Brush cells have been identified in the gastrointestinal (about 0.3% cells) and respiratory tracts, Identification of brush cells has relied primarily on morphology with electron microscopy; they have a distinctive pear shape with a wide base, and a narrow microvillous apex. The function of brush cells is to activate the digestion and absorption of sugars, amino acids and small chain carbohydrates in the bowel.
(See the following Internet page from the National Heart, Lung and Blood Institute: http://www.nhlbi.nih.gov/meetings/workshops/brush-cell.htm.)
“Digestive epithelium”: The digestive tube, which is comprised of comprised of the oral cavity (mouth), pharynx (throat), esophagus, stomach, small intestine, large intestine, and rectum is lined by a simple (1 cell thick) epithelium that is continuous at either end with the epidermis of the skin. This digestive epithelium is a mucosa, i.e. an epithelium that secretes watery mucus for the purpose of lubrication. (See http://www.sbs.utexas.edu/shankland/lc11dig1.htm)
The following is a list of all growth and differentiating factors detected by human ELISA tests built in with factors of human origin as standards. (See also FIG. 3 .)
BMP-2: bone morphogenic protein 2 BMP-4: bone morphogenic protein 4 EGF: epidermal growth factor FGF-2: (basic) fibroblast growth factor basic FGF-4: fibroblast growth factor 4 HGF: hepatocyte growth factor IGF-1: insuline-like growth factor 1 IGFBP-1: insuline-like growth factor binding protein 1 IGFBP-3: insuline-like growth factor binding protein 3 KGF (FGF-7): keratinocyte growth factor (fibroblast growth factor-7) PDGF-AA: platelet-derived growth factor-AA PDGF-AB: platelet-derived growth factor-AB PDGF-BB: platelet-derived growth factor-BB PLGF: placenta growth factor SCF: stem cell factor c-kit ligand TGF-α: transforming growth factor alpha TGF-β1: activated transforming growth factor beta 1 TGF-β2: activated transforming growth factor beta 2 TNFα: tumor necrosis factor alpha TNFβ: tumor necrosis factor beta VEGF: vascular endothelial growth factor
EXAMPLE 1
Isolation of Growth and Differentiating Factors from Commercially Available Bovine Colostrum
The process of the invention, shown schematically in FIGS. 1 (A) & (B), will now be described.
It should be appreciated here that while this process is specifically described for use with colostrum, substitutes for colostrum, namely other milks and milk products, may also be used. The efficiency of the process is believed to be enhanced with colostrum, because colostral milk contains a higher concentration of growth and differentiation factors than other milks and milk products. Colostral substitutes—filter sterilized milk, modified milk (i.e., milk from which the fatty constituents have been wholly or partially removed, with or without the addition of vitamins or solid elements derived from milk), enriched milk (i.e., enriched with non-fat solids), vitaminized milk (milk with vitamins added), and lacto-serum—may also be used as starting materials since they are known to contain growth and differentiation factors of a similar nature. However, not all the factors will be found in milk, and then, not in the same concentration as in colostrum. When using a colostral substitute, it will be necessary to modify the process slightly to maximize the yields of growth and differentiation factors. Such modifications should be within the purview of one of skill in the art.
1. Preliminary Preparation
When starting with a lyophilized colostral preparation (freeze dried colostrum exempt of fat, coliforms and antibiotics) it has been found that the best way to reconstitute colostrum is to dissolve 80 g per liter of water (18.2 Mega Ohms).
The best pH for extraction is between about 3.75 and 3.85. The colostrum is adjusted to this pH (with a 10 N HCl solution, for example) and then placed in an agitator (Hobart™), at the first speed for 60 minutes. The pH of the solution is readjusted, with NaOH 10 N, to a pH of about 4.52-4.55 and the solution agitated for another 15 minutes before being centrifuged for 20 minutes at 9285 G. The best results were observed using a Beckman™ Avanti J-20XPX-12 with rotor JLA 8.1 centrifuging 6 liters at a time for 20 minutes at 9285 G.
The combined precipitates are dissolved in water for re-extraction (12 liters of 18.2 Mega Ohms for every kg of precipitate) and centrifuged again for about 20 minutes at 9285 G. The supernatants from each bottle are added to the pooled supernatant (1) from the first centrifugation. The final pH of the solution sometimes needs to be readjusted as it will be 4.35-4.40 instead of the 4.50-4.65 required for optimal results.
The solution is now ready for filtration and lyophilization, as described below.
2. Filtration Using TAMILAB® Filter System
Using the solution obtained in step 1, filtration is conducted by passing the supernatant through progressively smaller filtration columns, or molecular sieves. The choice of molecular sieve will depend on the fraction that is sought. As shown in Table 1, these fractions are identified as LP1 to LP5, depending on the filtration column selected.
TABLE 1
Correspondence between Filtration Column and Fraction
Filtration Size
Retention
Fraction
0.2
μm
5 kDa
LP1
300
kDa
5 kDa
LP2
150
kDa
5 kDa
LP3
50
kDa
5 kDa
LP4
15
kDa
5 kDa
LP5
In accordance with one embodiment of the present invention, in order to obtain fraction LP3 (150 kDa-5 kDa), a first filtration is performed using a 0.20 μm column. A column of this size will eliminate unwanted factors quickly before the supernatant is passed through the 150 kDa column, which is the column that is suitable for the LP3 fraction.
Moreover, in-between fractions may also be generated. For example, fraction LP3 may be filtered on a 50 kDa molecular sieve (used to obtain LP4). The result will be a retentate having a cutoff molecular weight of 150 kDa to 50 kDa (LP3-LP4). Similarly, LP4 may be filtered on a 15 kDa molecular sieve (used to obtain LP5). The result will be a retentate having a cutoff molecular weight of 50 kDa to 15 kDa (LP4-LP5).
As may be seen in Table 2, certain in-between fractions or pools were found to be especially interesting. These are LP1-LP3, LP1-LP5 and LP3-LP5. To prepare the LP1-LP3 fraction or pool, the solution resulting from Step 1, above, is run through a column having a 0.2 μm cutoff and then through a column having a 150 kDa cutoff. Similarly, to prepare the LP1-LP5 fraction or pool, the solution resulting from Step 1, above, is run through a column having a 0.2 μm cutoff and then through a column having a 15 kDa cutoff. Likewise, to prepare the LP3-LP5 fraction or pool, the solution resulting from Step 1, above, is run through a column having a 150 kDa cutoff and then through a column having a 15 kDa cutoff.
3. Lyophilization
This operation must be done very carefully in order to maximize efficiency. The different fractions are divided into samples of 2.5 liters per tray on lyophilizer FTS and frozen at about −35° C. This method permits rapid freezing without liquid nitrogen.
In a FTS tray lyophilizer the tray must be placed one at a time at 4° C. without vacuum then frozen to −35° C. before applying vacuum (10-100 mThors) at −80° C. to −85° C. for approximately 36-48 hours; the lyophilized samples, once in the form of a fine powder (250-500 μm) are ready for encapsulation or ready to be pooled and conserved in storage bags (sterile freezer bags) at a temperature of approximately −18° C. to −20° C.
Using the process described above, it is possible to isolate growth and differentiating factors from colostrum. FIG. 2 shows the growth factors found in the following fractions, as verified through human ELISA testing: LP1, LP2, LP3, LP4, LP5, LP1-LP3, LP3-LP5 and LP1-LP5.
FIG. 3 reveals the quantities of certain of the growth factors identified in FIG. 2 . The quantities, measured through human ELISA, are per kg of colostrum.
Table 2 shows the quantity of isolated product per fraction for colostrum (1 kg; dry matter basis).
TABLE 2
Quantity of Isolated Product per Fraction for Colostrum
Fraction
Filter
Weight (g/Kg)
LP1
F 0.2 μm-R 5 kDa
≈90
LP2
F 300 kDa-R 5 kDa
≈55
LP3
F 150 kDa-R 5 kDa
≈35
LP4
F 50 kDa-R 5 kDa
≈25
LP5
F 15 kDa-R 5 kDa
≈20
LP1-LP3
F 0.2 μm-R 150 kDa
≈50
LP1-LP5
F 0.2 μm-R 15 kDa
≈70
LP3-LP5
F 150 kDa-R 15 kDa
≈30
EXAMPLE 2
Isolation of Growth and Differentiating Factors from Natural Colostrum (from Dairy Cows)
1. Preliminary Preparation
Frozen colostrum is thawed (storage temperature is −20° C.) then centrifuged 6 liters at a time at 20° C. The layer of butter and other residues are filtered first through cheesecloth and then through a Whatman™ 541 ashless filter. A thorough removal of this layer of fat will facilitate filtration and enhance the overall isolation of the growth and differentiating factors.
This preliminary filtration is followed by acid extraction at a pH of about 3.75-3.85. It is convenient to use a 10 N HCl solution for this purpose. If needed, water can be added to the supernatant (to a maximum of about 10%) in order to increase the fluidity of the supernatant for extraction. This greatly enhances filtration on the TAMILAB® system of columns (0.20 μm, 300 kDa, 150 kDa, 50 kDa, 15 kDa and 5 kDa), as will be described below.
The solution is now ready for filtration and lyophilization, as described in Example 1.
NB: As with Example 1, it should be appreciated here that while this process is specifically described for use with colostrum, substitutes for colostrum, namely other milks and milk products, may also be used. When using a colostral substitute, it may be necessary to modify the process slightly to maximize the yields of growth and differentiation factors. Such modifications should be within the purview of one of skill in the art.
EXAMPLE 3
Preferred Isolation Method for LP1-LP5
The following process is based on that shown schematically in FIGS. 1(A) and (B).
1. Isolation
1.1 Starting with a lyophilized colostral preparation (freeze dried colostrum exempt of fat, coliforms, E. coli, S. aureus , salmonella, clostridium and antibiotics, colostrum is reconstituted by dissolving 1000 g of raw colostrum per 12 liters of water (0.2 μm filtered), placed in a blending tank (Hobart™) and agitated for 15 minutes;
1.2 The pH is adjusted to between 3.75 and 3.85 with a 10 N HCl solution and run at ≈400 rpm for 60 minutes;
1.3 The pH of the solution is readjusted with a 10N NaOH solution, to a pH of about 4.50-4.60, and the solution agitated for another 15 minutes at the same speed;
1.4 The solution is centrifuged for 20 minutes at about 9285 G, 18° C. using a Beckman™ Avanti J-20XPX-12 with rotor JLA 8.1, centrifuging 6 liters at a time;
1.5 The supernatant is filtered on Whatman 541 Ashless filter and store in a 25 liter bottle at 4° C. until all centrifugation is completed and move on to filtration; and
1.6 The total quantity of quantity of solution to be filtered is between 20.5 to 21.5 liters.
2. Filtration Using TAMILAB® Filter System
2.1 Before starting filtration, the machine is rinsed by running 7 liters of alcohol (70%) through the system, letting 2 liters out and letting stand for 5 minutes before draining 5 liters;
2.2 The machine is rinsed again by running 5 liters of filtered water (0.2 μm) through the system, letting 2 liters out and draining from the system;
2.3 The solution from in step 1 is filtered by passing the supernatant through two 0.2 μm Dahlia ceramic columns with 1000 cm 2 surface (CéRAM from TAMI Industries);
2.4 The temperature of the solution in the filtration system should never exceed approximately 37° C. (if the temperature exceeds 37° C., the machine should be stopped for 15 minutes while the tank is refrigerated);
2.5 The filtration process is stopped at 4 liters less than the total starting quantity, the filtrate kept and stored at 4° C. until the next day and the system thoroughly drained;
2.6 9.5 liters of filtered water are run through the system (0.45 μm) heated at 100° C. with 500 ml of 10 N NaOH until it reaches 50-70° C.;
2.7 5 liters of filtered water are added and run until the tank is empty, and then drained from the system;
2.8 9 liters of filtered water are run through the system (0.45 μm), heated at 60-70° C. with 1 liter of 10N HCl, stopped and drained from the system;
2.9 7 liters of filtered water (0.2 μm) and 3 liters are run through and drained from the system;
2.10 7 liters of alcohol (70%) are added and 2 liters run through and the system drained;
2.11 0.2 μm columns are exchanged for 15 kDa columns;
2.12 7 liters of alcohol (70%) are run through the system, letting 2 liters out and letting stand for 5 minutes before draining the system;
2.13 The system is rinsed by running 5 liters of filtered water (0.2 μm) through it, letting 2 liters out;
2.14 The 0.2 μm filtrate is passed through two 15 kDa Dahlia ceramic columns with 1000 cm 2 surface (CéRAM from TAMI Industries);
2.15 The temperature of the filtration system should never exceed 37° C. (if it does, the machine should be stopped for 15 minutes);
2.16 The filtration process should be stopped at 3.5 liters less than the total starting quantity;
2.17 The system should be drained and the retentate kept;
2.18 The retentate should be centrifuged at 9285 G for 20 minutes;
2.19 The supernatant is ready for lyophilisation; it is stored at 2-4° C. until ready for processing;
2.20 To clean the filtering machine, points 2.6 to 2.10 are repeated;
2.21 In order to keep the system germ free, the process should always be finished with adequate cleaning procedures and the columns stored in alcohol.
3. Lyophilization
3.1 Using a FTS tray lyophilizer, the supernatant is processed according to the instructions for this equipment;
3.2 After the lyophilization is complete, the powder is passed through a 250 or 500 μm sieve under sterile environment;
3.3 The powder is conserved in sterile 50 ml centrifugation tubes, 20 grams per tube and stored at a temperature of about −16° C. to −24° C.;
3.4 The powder could be irradiated up to 8 kGy without loss of activity on human cells; and
3.5 The powder is stored at a temperature of about −16° C. to −24° C.
EXAMPLE 4
Isolation Results for Growth Factors IGF-1 and TFG-β 2 (after Partial Hydrolysis)
Growth Factors IGF-1 and TFG-β 2 were quantified in 2.5 ml fractions (hydrogenated, pH 3.9 colostrum) that were purified on HPLC. Tables 3 and 4 show the results for growth factors IGF-1 and TFG-β 2 , respectively.
TABLE 3
Quantification of IGF-1 in Retentate 21
Correction
Specific
Factor *
Quantity
Activity
Sample
Concentration
Dilution
IGF-1
(μg/g
(MW/% retentate)
No.
(mg/ml)
O.D.
factor
(ng/ml)
powder)
Fraction 2
X1
20.0
0.001
100 * 1
N/A
N/A
(>1400 kDa/2.8%)
Fraction 3
X2
20.0
0.005
100 * 1
N/A
N/A
(1400 kDa/5.6%)
Fraction 4
X3
20.0
0.007
100 * 1
N/A
N/A
(950 kDa/4.8%)
Fraction 5
X4
20.0
0.002
100 * 1
N/A
N/A
(680 kDa/4.3%)
Fraction 6
X5
20.0
0.001
100 * 1
N/A
N/A
(490 kDa/4.0%)
Fraction 7
X6
20.0
0.002
100 * 1
N/A
N/A
(350 kDa/3.2%)
Fraction 8
X7
20.0
0.002
100 * 1
N/A
N/A
(250 kDa/4.1%)
Fraction 9
X8
19.7
−0.001
100 * 1
N/A
N/A
(180 kDa/2.8%)
Fraction 10
X9
20.0
0.002
100 * 1
N/A
N/A
(133 kDa/16.6%)
Fraction 11
X10
20.1
0.005
100 * 1
N/A
N/A
(96 kDa/11.3%)
Fraction 12
X11
20.0
0.061
100 * 1
48.4
2.42
(70 KDa/5.5%)
Fraction 13
X12
20.0
0.231
100 * 1
125.1
6.26
(>45 kDa/2.8%)
Fraction 14
X13
20.0
0.081
100 * 1
58.5
2.93
(35 kDa/7.4%)
Fraction 15
X14
20.0
0.058
100 * 1
46.9
2.35
(26 kDa/4.1%)
Fraction 16
X15
20.0
0.056
100 * 1
45.9
2.29
(20 kDa/3.0%)
Fraction 17
X16
20.0
0.113
100 * 1
74.7
3.73
(13 kDa/1.9%)
Fraction 18
X17
20.0
0.146
100 * 1
91.3
4.57
(10 kDa/1.6%)
Fraction 19
X18
10.0
0.257
100 * 1
147.3
14.73
(7 kDa/0.7%)
TABLE 4 Quantification of TGF-β 2 from Retentate 21-CLAR in Fractions 2 to 25 purified with HPLC a Correction b corrected Specific Concen- Over- Factor * TGF-β 2 Activity Sample tration estimation Dilution Quantity (μg/g (MW/% retentate) No. (mg/ml) O.D. O.D − 0.120 factor (pg/ml) powder) Fraction 2 Xl 9.9 0.948 0.828 7.8 * 1 4161.1 420.32 (>1400 Kda/2.0%) Fraction 3 X2 10.1 1.061 0.941 7.8 * 1 4747.1 470.01 (1400 Kda/4.7%) Fraction 4 X3 9.8 1.607 1.487 7.8 * 1 7604.8 776.00 (950 Kda/3.1%) Fraction 5 X4 9.8 3.258 3.138 7.8 * 1 16410.2 1674.52 (680 Kda/2.6%) Fraction 6 X5 10.0 3.460 3.340 7.8 * 1 17499.2 1749.92 (490 Kda/2.3%) Fraction 7 X6 10.1 3.013 2.893 78 * 1 15092.3 1494.29 (350 Kda/2.2%) Fraction 8 X7 9.9 1.472 1.352 7.8 * 1 6894.7 696.44 (250 Kda/2.4%) Fraction 9 X8 10.0 0.372 0.252 7.8 * 1 1222.2 122.22 (180 Kda/7.0%) Fraction 10 X9 10.0 0.435 0.315 7.8 * 1 1538.0 153.80 (I33 Kda/12.2%) Fraction 11 X10 9.9 1.725 1.605 7.8 * 1 8227.0 831.01 (96 Kda/7.3%) Fraction 12 X11 10.2 2.314 2.194 7.8 * 1 11351.6 1112.90 (70 Kda/3.9%) Fraction 13 X12 9.9 0.625 0.505 7.8 * 1 2500.7 252.59 (50 Kda/3.6%) Fraction 14 X13 9.9 0.117 −0.003 7.8 * 1 N.A. N.A. (35 Kda/7.3%) Fraction 15 X14 10.2 0.115 −0.005 7.8 * 1 N.A. N.A. (26 Kda/4.8%) Fraction 16 X15 10.1 0.131 0.011 7.8 * 1 N.A. N.A. (20 Kda/3.0%) Fraction 17 X16 10.2 0.128 0.008 7.8 * 1 N.A. N.A. (l3 Kda/2.6%) Fraction 16 X17 9.9 0.115 −0.005 7.8 * 1 N.A. N.A. (l0 Kda/l.7%) Fraction 19 X18 10.0 0.115 −0.005 7.8 * 1 N.A. N.A. (7 Kda/1.2%) Fraction 20 X19 10.0 0.116 −0.004 7.8 * 1 N.A. N.A. (5 Kda/1.2%) Fraction 21 X20 10.0 0.090 −0.030 7.8 * 1 N.A. N.A. (3.5 Kda/0.6%) Fraction 22 X21 10.0 0.098 −0.022 7.8 * 1 N.A. N.A. (2.5 Kda/0.8%) Fraction 23 X22 10.0 0.086 −0.034 7.8 * 1 N.A. N.A. (2 Kda/0.3%) Fraction 24 X23 10.0 0.126 0.008 7.8 * 1 N.A. N.A. (1.5 Kda/0.2%) Fraction 25 X24 10.0 0.092 −0.028 7.8 * 1 N.A. N.A (1 Kda/0.3%)
Discussion
The results in Tables 3 and 4 are but two examples showing the specific activity of the pools of factors derived using the process of the present invention. Partial hydrolysis converts many factors from their inactive (or “pro”) forms (>450 kDa) to their active forms. Significantly, these factors, which are present in pools in the various fractions, as verified through human ELISA testing ( FIG. 3 ), have been found to be active on human cells.
EXAMPLE 5
Effect on Cell Behavior of a Variety of Purified Fractions
1. Objectives of the Study
The objectives of the study were to evaluate the effect on cell behavior of a variety of fractions purified with the process of the present invention. The pools tested were termed LP1, LP2, LP3, LP4, LP5, LP1-LP3, LP3-LP5 and LP1-LP5. The proliferation and growth of human fibroblasts as well as their collagen synthesis were investigated in vitro in order to select optimal pools for further study. In addition, some studies were also performed with human vascular endothelial cells.
2. Materials and Methods
2.1. Cells
Human fibroblasts, stored in liquid nitrogen, and derived from foreskin of young were used at passages 3-8. Fibroblasts were grown in Dulbecco's modified Eagles medium with 5% fetal bovine serum (FBS). Ascorbic acid and β-aminoproprionitrile were added to the cultures dedicated to the collagen synthesis assessment.
Human vascular endothelial cells, stored in liquid nitrogen and derived from umbilical veins (HUVECs), were used at passages 3-4. HUVECs were grown on gelatin-adsorbed culture dishes in Medium 199 containing 10% FBS, L-glutamine (2 mM) and endothelial cells growth supplement (ECGS at 20 μg/ml). To test the pools, serum-free Medium 199 was used with ECGS and L-glutamine to permit cell survival. In a pilot experiment, endothelial cells died in less than 24 hrs when grown in culture without ECGS and serum.
2.2. LP Pool Concentrations
In the first set of experiments, LP pools were diluted to final concentrations of 0.1, 1.0, 10 mg/ml. In the following sets of experiments, the final concentrations tested were 0.33, 1.0, and 3.3 mg/ml. These conditions were compared to negative control cultures free of serum. In some cases, serum-supplemented medium was used in positive control cultures.
2.3. Proliferation Test (Cyquant® Assay from Molecular Probes)
Cells were seeded in wells of 24 multiwell plates at a density of 5×10 3 fibroblast/well and a density of 1×10 4 endothelial cells/well and grown for 6-24 hrs to allow cell adhesion in the presence of serum (5% for fibroblasts, and 10% for endothelial cells). At time zero, medium was removed and cells were rinsed twice with Hank's balanced salt solution (HBSS), then replaced by culture serum-free medium containing the LP pool to be tested at different concentrations. Control cultures were grown in parallel. After 12 or 24 hours of growth without changing medium, medium was removed, and the wells were rinsed twice in PBS. Multiwell plates were frozen at −70° C. Two hours later, plates were thawed, the lysis buffer (solutions A and B, provided with the kit, revealing fluorescent solutions) was added with an incubation of 3-5 minutes, then fluorescence was read in a cytoplate with a BioTek FL-600 fluorometer at 480 nm excitation and 520 nm emission.
2.4. Cell Growth (Hoechst)
Cells were seeded in wells of 24 multiwell plates at a density of 1×10 4 fibroblast or endothelial cells/well and grown overnight (or 24 hrs in the first set of experiment) to allow cell adhesion in the presence of serum (5% for fibroblasts, and 10% for endothelial cells). The next day (time zero), medium was removed and cells were rinsed twice with HBSS, then replaced by culture serum-free medium containing the LP pool to be tested at different concentrations. After 72 hours of growth without changing medium, medium was removed, and the wells were rinsed twice in PBS. Then, PBS was replaced by a 200 μl saline-sodium citrate buffer (SSCI) solution containing 0.1% SDS, and incubated for 1 hour at 37° C. Twenty (20) μl of Hoechst 33258 solution (at 1 mg/ml) was added to the SSCI solution. After agitation (up-down), fluorescence was read in a cytoplate at 340 nm excitation and 460 nm emission with a sensitivity set at 100-120.
In parallel, incrementing cell density was established, incubated with Hoechst 33258 solution (at 1 mg/ml), then fluorescence was read to perform a standard curve in which the cell number is plotted against the optical density.
2.5. Statistic Analyses
One Way Analysis of Variance was used for the statistical analysis of quantitative data, with a p value ≦0.05. Bonferroni t-test method was used for all pairwise comparison procedures.
2.6. Collagen Synthesis in Monolayer Fibroblast Cultures
Cells were seeded in wells of 24 multiwell plates at a density of 1×10 5 fibroblast/well and grown overnight to allow cell adhesion in the presence of serum (5%), ascorbic acid (10 μg/ml) and β-aminoproprionitrile (10 μg/ml). The next day (time zero), medium was removed, rinsed with PBS, and cells were exposed to medium containing LP pools, and radioactive proline ( 14 C or 3 H proline). Control cultures were run in parallel. Cultures lasted for 7 days to allow collagen synthesis and deposition, for which fresh medium containing LP pools and radioactive proline was changed every other day. At medium changes, media of each condition were collected and pooled (i.e., soluble collagen). At the end of the 7 day culture period, cells and matrix were pooled (i.e., cellular, insoluble and deposited collagen), separately of the medium pools (i.e., soluble collagen). Matrix-cells and media were promptly diluted in a protease cocktail inhibitor solution. Matrix-cell pools were counted on a scintillation counter, whereas medium pools were dialyzed to remove any free radioactive proline, then counted.
2.7. Cell Cultures in 3-D Fibrin Gel and Collagen Synthesis/Deposition
Fibrin gel was used instead of collagen gel in order to investigate the collagen/deposition by fibroblasts, since collagen itself is known to inhibit collagen synthesis. Moreover, fibrin represents the primary extracellular matrix during wound healing. A 3 mg/ml fibrinogen solution was mixed with 5×10 4 fibroblasts/ml and polymerized by thrombin in the wells. The fibrin gels were then covered with culture medium containing the different LP pools, and radioactive proline. The method to analyze collagen synthesis and deposition was similar to that described earlier in Section 2.6, above.
3. Results
3.1. Fibroblast Proliferation
Proliferation was measured at 12 and 24 hrs of cultures in the presence of LP pools with incrementing concentrations.
At 24 hours, 1 mg/ml LP1 and LP1-LP3 induced a statistically significant higher value compared to the other LPs and control culture with no serum (not shown). At 10 mg/ml, the values with LP1 were significantly higher than those with LP1-LP3 at the same concentration. The latter was not different statistically with 10 mg/ml LP2, but different with 10 mg/ml LP3, LP4 and LP5. The values of LP1 were similar at 1 and 10 mg/ml. The values between 1 and 10 mg/ml of LP1-LP3 and LP2 were also similar. The values with 1 and 10 mg/ml LP1, LP2 and LP1-LP3 were significantly higher than those at 0.1 and control. The values of LP4 and LP3 were not significantly different. High doses of LP5 induced a significant inhibition compared to control and the other LP pools at 10 mg/ml.
At 12 hrs (not shown), the values of cell proliferation at 0.33, 1 and 3.3 mg/ml of LP1-LP3 was statistically higher than the other conditions, except with 3.3 mg/ml LP-2 which was similar to LP1-LP3. However, the values with 3.3 mg/ml LP2 were not different than LP1, LP3, LP4 and LP5 at the same concentration.
3.2. Fibroblast Growth
The first assay was performed with 0.1, 1.0 and 10 mg/ml of LP pools (not shown). There was a statistically significant increase in the presence of LP1-LP3 at 1 and 10 mg/ml and between 1 and 10 mg/ml LP1-LP3. LP1-LP3 did not reach the number of cells found in the control cultures in serum-supplemented medium, which was 1.5-fold increase.
A significantly higher number of cells was found in the presence of 10 mg/ml LP1, LP2, LP3 and LP4 compared to those pools at lower doses, control without serum, and to 10 mg/ml LP5. The presence of LP5 resulted in a significant inhibition at the highest dose (10 mg/ml).
A second set of experiments was performed with 0.33, 1.0 and 3.3 mg/ml of LP pools ( FIG. 4 ). The numbers of cells in the presence of 1.0 and 3.3 mg/ml LP1-LP3 were significantly higher than those of the other pools and the control cultures without serum, except 3.3 mg/ml LP2, which resulted statistically in a similar number of cells than that with 3.3 mg/ml LP1-LP3. The cell number with 3.3 mg/ml LP2 was not significantly different than that with 3.3 mg/ml LP3. In addition, LP1-LP3, LP2 and LP3 had a significant increase in cell numbers between 1 and 3.3 mg/ml.
A third set of experiments was conducted with new pools LP1-LP3, LP3-LP5 and LP5 ( FIG. 5 ). The number of cells in the presence of 3.3 mg/ml LP1-LP3 was significantly higher than the other conditions. The cell number with 1.0 and 3.3 mg/ml LP3-LP5 was significantly different than 3.3 mg/ml LP5. The cell number with 1.0 mg/ml LP1-LP3 and LP3-LP5 were not found to be statistically different, but different compared to LP5 and controls.
3.3. Proliferation of HUVECs
The Cyquant® assay shows a significant increase in the proliferation within 12 hours in the presence of LP1-LP3 at 0.33, 1.0 and 3.3 mg/ml, as compared with the other conditions ( FIG. 6 ). However, the values for 3.3 mg/ml LP1-LP3 were close to those with 3.3 mg/ml LP2, and those for 1.0 mg/ml LP1-LP3 were not different than those of 1.0 mg/ml LP1, LP2 and LP5.
3.4. Growth of HUVECs
A drop in cell number (from 10,000 cells at seeding time to 3,700 cells after more than 72 hrs of incubation) was observed (not shown), due to the lack of serum since these cells are very dependent on it. Once again, the exposure to LP1-LP3 significantly enhanced cell growth at the 3 doses tested, compared to the other pools and the control cultures, recovering the initial number of cells. However, the cell number with 3.3 mg/ml LP1-LP3 was close to that of 3.3 mg/ml LP3. LP3 also increased significantly the number of cells when used at 3.3 mg/ml. Conversely, a high dose of LP1 inhibited endothelial cell growth.
3.5. Collagen Synthesis and Deposition in Monolayer
The presence of LP1-LP3, particularly at 1.0 and 3.3 mg/ml, enhanced collagen synthesis, as shown by increased radioactivity ( FIG. 7 ). Similar doses of LP3 and LP2 also increased collagen synthesis, but to a lesser degree.
Phase contrast microscopy shows the extracellular matrix deposition and cells (not shown). LP2 induced matrix between cells particularly with 3.3 mg/ml. LP3 also enhanced matrix deposition at all doses tested. The behavior of cells in the presence of 1.0 and 3.3 mg/ml LP1-LP3 appeared different from the others with a reorganization of cells into a network, rarely seen in monolayer cell cultures.
In another set of experiments, the effects of LP1-LP3, LP1-LP5 and LP3-LP5 were compared. The CPM values were reported to the cell number at day 7.
Thus, collagen synthesis and deposition per cell was particularly enhanced in the presence of 0.33, 1.0 and 3.3 mg/ml of LP1-LP5, even above the value found in the presence of serum ( FIG. 8 ). Moreover, the values of collagen synthesis and deposition were elevated in the presence of LP1-LP3 and LP3-LP5.
3.6. 3-D Cell Cultures and Collagen Synthesis
In a first set of experiments, cell and matrix pools showed an increase in collagen synthesis and deposition with LP2 and LP3, particularly at 3.3.mg/ml (not shown). LP1-LP3 also enhanced collagen synthesis at 3.3 mg/ml, but less than LP2 and LP3. Phase contrast microscopic observation (not shown) shows numerous cells with extracellular matrix deposition at day 7, in the presence of 1 and 3 mg/ml LP2 and LP3 and 1 mg/ml LP1-LP3, all compared to the control and LP1, LP4 and LP5.
A second set of experiments was performed with new LP1-LP3, LP3-LP5 and LP5 pools. Afterwards, fibrin gels were detached from the wells to allow contraction. LP1-LP3 induced an increase in collagen synthesis and deposition in the cell-matrix pools, which was close to that observed in the presence of serum ( FIG. 9 ). LP3-LP5 induced less collagen synthesis, higher than that in the control without serum. Cell cultures were observed by phase contrast microscopy at day 8. One and 3.3 mg/ml LP1-LP3 resulted in a dense matrix with few cells, when compared particularly with the control cultures and LP5 ( FIG. 10 A-D). By day 9, the contraction occurred that resulted in a floating fibrin gel. The latter was very dense in the presence of 3.3 mg/ml LP1-LP3 ( FIG. 10 E-F).
Another study was performed with LP1-LP5. In the presence of LP1-LP5, fibroblasts in fibrin gels were reorganized into a network, particularly at 1 mg/ml, as shown in FIG. 10 G. Moreover, at a higher dose (3.3 mg/ml) of LP1-LP5, the fibrin gel was likely dissolved, perhaps by fribrinolysis, and some residual fibrin particles aggregated ( FIG. 10 H). Measurement of collagen synthesis and deposition show less production than with LP1-LP3, with an increase at 3.3 mg/ml (not shown). However, considering the decrease in cell density by day 9, collagen production was more elevated in the presence of LP1-LP5.
4. Discussion and Conclusion
The data shows clearly that cell proliferation and growth are stimulated by the presence of LP1-LP3 (3.3-fold increase in cell number), even with doses as low as 0.33 mg/ml as observed in some experiments, and this is incrementing as a function of the dose. Similarly, but to a lesser degree, LP2, LP3, and LP3-LP5 stimulate cell growth and replication when 3.3 mg/ml is used. The stimulation of cell replication in the presence of LP1 appears only after 24 hours, and the consequence on cell number is perceptible when high dose of 10 mg/ml is used. Furthermore, the proliferation and growth of vascular endothelial cells are also stimulated by the presence of LP1-LP3. Assessment of endothelial cell growth shows an incrementing effect as a function of dose. LP3 and LP2 may also enhance cell replication and growth, but to a lesser degree.
The observation and quantification of collagen synthesis and deposition show different patterns in monolayer cell cultures versus 3-D cultures in fibrin gel, more specifically in the presence of LP2 and LP3. The two latter induce a significant increase in collagen synthesis and deposition by fibroblast in fibrin gel, particularly with 3.3 mg/ml. On the other hand, LP1-LP3 also increases, but at a less degree, collagen synthesis and deposition. LP1-LP3 also increases the organization of fibroblasts in a monolayer and more specifically in a fibrin gel (since they have a matrix to attach and migrate), as observed on micrographs. This observation is confirmed by the induction of a dense contracted matrix after days in culture. This suggests that newly formed collagen deposited in fibrin is remodeled by fibroblasts. Conversely, LP3-LP5 is less efficient to induce newly formed collagen, compared to LP1-LP3. On the other hand, LP1-LP5 induces synthetic activity as demonstrated in monolayer cultures. Whereas in 3-D fibrin gel, a differentiation activity is exhibited that involved protease activation as observed during wound remodeling.
Without wishing to be bound by any theory, the effect of LP1-LP3 on collagen synthesis and deposition may be explained by the presence of high cell density at the start of the cell cultures, due to the stimulation of cell replication as determined by the different assays. Although the LP pools are renewed at medium change during the 7-9 day period of fibroblast cultures for collagen synthesis assay, it appears that by 8 days the cell density is less than expected, and less than that observed in the control culture with serum. Thus, LP1-LP3 not only enhances fibroblast proliferation and growth, but also the biosynthetic activity of fibroblast towards the formation of collagen, its deposition, and its remodeling.
In conclusion, selective LP pools such as LP1-LP3, LP2, LP3 and LP5 have potential and specific effects on fibroblasts and endothelial cell behaviour. These pools may have a beneficial effects in wound healing and closure.
EXAMPLE 6
Proliferation and Growth of Human Fibroblasts, and Collagen Synthesis
1. Objectives of the Study
The objectives of the study were to evaluate the effect on cell behavior of the growth and differentiating factors present in three pools: LP1-LP3, LP3-LP5 and LP1-LP5. The proliferation and growth of human fibroblasts as well as their collagen synthesis were investigated in vitro for a comparative study.
2. Materials and Methods
2.1. Fibroblasts
Human fibroblasts were used in conditions similar to those described in Example 5. They were derived from the same batch used in the previous experiments.
2.2. LP Pools Concentrations
LP pools were diluted to final concentrations of 0.33, 1.0, and 3.3 mg/ml. These conditions were compared to negative control cultures in serum-free medium and positive control cultures in serum-supplemented medium.
2.3. Test of Proliferation (Cyquant® Assay); Cell Growth (Hoechst); and Collagen Synthesis in Monolayer and in Fibrin Gel Cultures ( 14 C-Proline)
The experimental method used was similar to that described earlier, as was the statistical comparison.
3. Results
3.1. Fibroblast Proliferation ( FIG. 11 )
Cell proliferation after 24 hrs of culture was increased, more specifically with 1.0 and 3.3 mg/ml of LP1-LP3 and LP3-LP5 pool. Statistical analyses show that the values of 1.0 mg/ml LP1-LP3 and those of 3.3 mg/ml LP1-LP3 and LP3-LP5 were significantly higher than those of the control with no serum. Due to large variations in the values with LP1-LP5 pools, the cell proliferation values were not significantly different than those of the control.
3.2. Fibroblast Growth
Cell growth increased as a function of the doses tested for the different pools (not shown). The values of 3.3 mg/ml LP1-LP3 were significantly higher than all the other conditions, except with the control cultures in the presence of serum. The values of 3.3 mg/ml LP1-LP5 were significantly higher than all the other conditions, except LP1-LP3 and LP3-LP5 both at 3.3 mg/ml (similar), and the presence of serum (lower). The values of 3.3 mg/ml LP3-LP5 were significantly different than those of the two control cultures. Statistically, the values of 1.0 mg/ml LP1-LP3 were significantly different than those of the two control cultures. Moreover, the values at 0.33 mg/ml were different for LP1-LP3 and LP3-LP5, compared to the control cultures with no serum.
3.3. Collagen Synthesis and Deposition in Monolayer
After 7 days in cell culture, collagen synthesis and deposition was elevated for LP1-LP3 and LP3-LP5. However, when the values were reported with respect to the cell number, collagen synthesis and deposition per cell was particularly enhanced in the presence of 0.33, 1.0 and 3.3 mg/ml of LP1-LP5, even above the value found in the presence of serum. Observation of the cell cultures shows clearly less cells left in the presence of LP1-LP5, more specifically with the highest concentration tested compared to the other conditions. In the presence of serum, a dense population of cells was seen, for little quantities of formed collagen. Moreover, the values of collagen synthesis and deposition were higher in the presence of LP1-LP3 and LP3-LP5. Specifically, 3.3 mg/ml of LP3-LP5 enhanced collagen synthesis and deposition. The curve of LP1-LP3 resembles that reported earlier in monolayer cell culture. The ratio of soluble collagen versus insoluble collagen was relatively constant in any conditions tested.
3.4. 3-D Cell Cultures and Collagen Synthesis and Deposition
While experimental conditions were not optimal due to a weakness in fibrin gel formation resulting from a limited number of cells (2×10 5 cells/well instead of 5×10 5 cells/Well), some of the data generated is of interest. In fibrin gel, LP1-LP5 behaved differently compared to LP1-LP3 and LP3-LP5. Observation of cells shows a clearly diminished number of cells as well an organisation of the fibroblasts into a network in the presence of 1.1 mg/ml LP1-LP5. This has not been observed with other components, and may correspond to dramatic cell differentiation. Moreover, LP1-LP5 at 3.3 mg/ml appeared to induce the dissolution of the fibrin gel, and it is accompanied by cell death and loss after each medium change (radioactivity value was not determined). The latter phenomenon may be induced by excessive protease activation, in particular plasminogen activators secreted by fibroblasts that have differentiated. In one instance (not shown), LP1-LP3 increased the formation of soluble and insoluble collagen slightly. However, it did not show any stimulation when the values of cpm were reported to the number of cells. LP3-LP5 increased the collagen production per cell. On the other hand, LP1-LP5 appeared to enhance collagen synthesis and deposition when the values were reported to the number of cells.
4. Discussion and Conclusion
The three LP pools of pools stimulate cell proliferation and cell growth, particularly the LP1-LP3 at high dose of 3.3 mg/ml. Although the stimulation of cell growth by LP1-LP3 occurs, collagen synthesis and deposition was limited when compared specifically with LP1-LP5. The latter induces a significant increase of collagen formation in monolayer cell culture and in 3D fibrin gel. Moreover, the presence of LP1-LP5 results in a cell differentiation into cord-like structures, but at high doses proteases are likely to be involved.
In conclusion, the LP1-LP5 pool of factors induces cell differentiation along with synthetic activity rather than proliferative and growth activity. The synthetic activity is accurately demonstrated in monolayer cultures, while the differentiation activity is exhibited in 3D fibrin gels.
EXAMPLE 7
Cell Proliferation Effect of LP1-LP5 Pool of Growth Factors on Chondrocytes
The effect on chondrocyte proliferation of the LP1-LP5 pool of growth factors was measured. FIGS. 12 , 13 and 14 show the effect on chondrocyte proliferation of 1 mg/ml and 3 mg/ml LP1-LP5 after 3 days, 7 days and 10 days, respectively. Two and ten percent fetal bovine serum (FBS) served as controls. FIG. 15 shows the proliferation (number of chondrocytes) due to 1 mg/ml of LP1-LP5 over the same three periods of time.
As may be appreciated from the results, chondrocyte proliferation was enhanced in the presence of both 1 mg/ml and 3 mg/ml LP1-LP5. FIGS. 12 , 13 and 14 reveal that after three days the proliferation is similar to that for cells incubated with FBS. However, by days 7 and 10, chondrocyte proliferation is markedly increased in the presence of LP1-LP5.
EXAMPLE 8
Wound Healing Capabilities of LP1-LP3, LP1-LP5 and LP3-LP5 Pools of Growth Factors
The wound healing capabilities of LP1-LP3, LP1-LP5 and LP3-LP5 were investigated in a guinea pig model. Briefly, 9 male guinea pigs were used in the experiments. (The protocol was accepted by the Committee for the Protection of Animals of the Centre hospitalier universitaire de Québec (CHUQ).) Under general anesthesia (isoflurane with oxygen) and using dermatological punches, four 6-mm (diameter) punch biopsies were made in the backs of each animal.
The wounds were arranged so that three wounds were positioned on one side of each animal's back in order to receive a sample of one of the three pools to be tested (2 mg per wound of LP1-LP3, LP1-LP5 or LP3-LP5), and one wound was positioned on the other side of the back to receive physiological liquid (0.9% saline solution). This arrangement was devised to minimize cross-contamination between the wounds. The animals were sacrificed after 7, 14 and 28 days according to the following schedule: one animal given an LP1-LP3 dosage was sacrificed after 7 days, a second after 14 days and a third after 28 days; one animal given an LP1-LP5 dosage was sacrificed after 7 days, a second after 14 days and a third after 28 days; and one animal given an LP3-LP5 dosage was sacrificed after 7 days, a second after 14 days and a third after 28 days.
FIG. 16 shows the epidermal covering (epidermization) at day 7 of the three pools. FIG. 17 reveals the diminution of wound areas (granulation tissue) after 7 days, 14 days and 28 days. FIG. 18 shows the wound or dermal thickness after 7 days and 14 days, while FIG. 19 reveals the degree of newly-formed collagen fibers after 7 days, 14 days and 28 days.
In a separate but related experiment, the ratio of epidermization resulting from pools LP1, LP1-LP3 and LP1-LP5 after 5, 7 and 10 days was investigated (see FIG. 20 ). The results reveal that wound closure occurs much more rapidly in the presence of these pools than they would otherwise (see percent epidermization of pools compared to serum at 7 days, for example). Interestingly, the wound closures were devoid of keloids.
Quantification has allowed the demonstration of the reduction in surface area occupied by granulation tissue, as well as a diminution in its thickness, especially early on (at days 7 and 14) with the LP1-LP5 pool of growth factors. This reduction is accompanied by a rapid deposition of collagen (particularly at day 7), which does not occur to a significantly greater degree subsequently. It should also be noted that at day 7, in the presence of LP1-LP5, wound contraction is much augmented in comparison to the other conditions at this time. These observations would suggest that LP1-LP5 has a moderate scarring activity, while avoiding excess tissue repair as is observed during foetal scarring, for example. No differences in the migration and epidermal covering have been found, which leads to the supposition that LP1-LP5 acts preferentially on granulation tissue, under the assay conditions used (in vivo).
EXAMPLE 9
Precocious Maturation (Differentiation) of Brush Cells
Brush cells incubated with 1% serum along with growth factor pools LP1-LP3, LP1-LP5 and LP3-LP5 differentiate faster than cells incubated solely with 1% or 10% serum. As may be seen from FIG. 21 , the specific activity of alkaline phosphatase is significantly increased for cells exposed to LP1 and LP1-LP5, even before confluence. An increase in the specific activities of sucrase and lactase is also observed, post confluence, especially with pools LP1 and LP1-LP5, as may be observed from FIGS. 22 and 23 , respectively.
Interestingly, brush cells, pre-confluence, incubated with the different pools, and particularly with LP1 and LP1-LP5, demonstrated a degree of polarization that is significant when compared to cells incubated in 1% and 10% serum (not shown). These cells exhibited a cuboidal morphology and appeared to be squeezed more tightly against each other.
The above observations have significant implications as far as the digestive epithelium is concerned. The use of the growth factor pools speeds up the maturation and differentiation of brush cells, leading them to generate their digestive enzymes (lipases, amylases and proteases) more rapidly. The pools could therefore be used to treat compromised digestive systems, such as those of premature and mature newborns or individuals suffering from GI tract ailments (inflammations and obstructions).
EXAMPLE 10
Uses or Applications for Various Growth Factors
The growth factors that are isolated through the novel process of the present invention may be used in a number of applications, including: cosmetics, cosmeceuticals, nutraceuticals and food additives, as well as in dermatological, pharmaceutical, medical and veterinary applications. Suggested applications for the specific growth factors found in individual fractions (see FIG. 1(B) and FIG. 3 for the factors found in the various fractions) are listed in Table 5.
Interestingly, fraction LP5, which is the filtrate passing through the microfilter of 5 kDa (FIG. 1 (B)), may also be useful in a number of applications. LP5 has been found to contain a wealth of vitamins, trace elements, amino acids, natural peptides and salts, among other pools. It can therefore be used as a diluent in the manufacture of cosmetic products and as an effluent in the preparation of nutraceutical substances, among other applications.
TABLE 5
Uses or Applications for Growth Factors in Specific Fractions
Fraction
Applications
PPT (cheese)
Emergency nutrient for prized calfs born
by Caesarean section (IGMs and
primary casein), trace IgG and IgM
W541 - 0.2 μm
Emergency nutrient pH 4.50 = soluble
casein and partially hydrolyzed globulins
For prized calfs born by Caesarean
section not having access to maternal
colostrum
LP1
Nutraceutical (digestive inflammation)
LP2
Nutraceutical (digestive inflammation)
(with traces of primary casein)
LP3
Cosmetic and cosmeceutical;
Nutraceutical (digestive inflammation of
the bowel) (without casein and gamma-
globulin)
LP4
Dermal pool of mature growth factors of
low molecular weight for transdermal
applications (for the manufacture of high
end cosmetics without bacteria or
viruses)
LP5*
Food and beverage supplement;
vitamins, salts, amino acids, lactose,
oligoelements and small peptides
LP1-LP3
Cell proliferation and some
differentiation (collagen secretion and
maturation)
LP3-LP5
Cell proliferation but even more
differentiation (collagen secretion and
maturation) relative to LP1-LP3
LP1-LP5
Cell proliferation and differentiation
(collagen secretion and maturation);
contractility of the dermis; elaboration of
specific digestive enzymes, etc.
*NB: The LP5 extract includes the following: Lactose (13%); calcium (1.2%); sodium (0.3%); phosphorus (0.6%); magnesium (0.2%); potassium (0.8%); alanine (2.9 g/100 g protein); arginine (1.5 g/100 g protein); aspartic acid + asparagine (9.5 g/100 g protein); cystein (1.9 g/100 g protein); glutamic acid + glutamine (20.1 g/100 g protein); glycine (2 g/100 g protein); histidine (1 g/100 g protein); isoleucine (4.4 g/100 g protein); leucine (10 g/100 g protein); lysine (4.5 g/100 g protein); methionine (2.2 g/100 g protein); phenylalanine (6.1 g/100 g protein); proline (3.6 g/100 g protein); serine (7.2 g/100 g protein); threonine (7.3 g/100 g protein); tryptophan (0.9 g/100 g protein); tyrosine (7.9 g/100 g protein); valine (6.9 g/100 g protein); IGF1 (monomer 7 kDa and dimer 14 kDa) (0.1-0.7 mg/100 g); TGF-β2 (85% and TGF-β) (0.06-0.46 g/100 g); lactoferrin (0.16 g/100 g); lactoperoxydase (9.1 mg/100 g); lysozyme (0.16 mg/100 g); vitamin A (5 μg/g MG); vitamin B12 (23 μg/100 g); choline (0.3 mg/100 g); folic acid (3.8 μg/100 g); riboflavin (23 μg/100 g); thiamin (0.28 mg/100 g); biotin (13 μg/100 g); nicotinic acid (0.46 mg/100 g); ascorbic acid (12 μg/100 g); and pantothenic acid (0.8 mg/100 g).
Although the present invention has been described hereinabove by way of preferred embodiments thereof, it can be modified without departing from the spirit, scope and nature of the subject invention, as defined in the appended claims.
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The present invention concerns a novel process for isolating growth and differentiating factors present in colostrum, all in a natural way. This process is characterized by maturation steps (controlled mild acid hydrolysis) and physical steps (molecular filtration) which optimize recovery of measured growth factors and their ability to entice a response on human cells. Advantageously, this process allows the derivation and isolation of growth and differentiating factors with highly disparate sizes (or molecule weights) in pools. These pools can be used in select and varied ways, including cosmetic, cosmeceutical, nutraceutical, dermatological, pharmaceutical, medical and veterinary applications. It can also be used as a replacement to fetal calf serum to promote cell proliferation, and above all, cell differentiation.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/621,864 filed on Apr. 09, 2012.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
COPYRIGHT NOTICE
[0003] A portion of the disclosure of this patent document contains material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or patent disclosure as it appears in the United States Patent and Trademark Office patent file or records, but otherwise reserves all copyrights whatsoever.
BACKGROUND
[0004] (1) Field of the invention
[0005] Relating to improvements in devices used for oral hygiene.
[0006] Men and women have always sought to keep themselves clean in order to appear fresh and presentable to themselves and to their neighbors. They primarily do this by maintaining proper hygiene using a simple routine of daily showering using soap and shampoo as well as proper cleaning of the mouth through the use of a toothbrush. There are many forms of brushes available on the market today that are typically made to support the needs of different users; amongst these are electric brushes, brushes designed with bristles having varying surface patterns, ergonomic brushes supporting different hand postures and brushes with angled brush head.
[0007] Amongst the electric type there are electric toothbrushes including those that are battery powered as well as those that are powered by a conventional wall outlet. However, a problem arises in that the brushes described previously are of no help whatsoever in the event that you can not get a tube of toothpaste. Perhaps the store has run out of a user's favorite brand of toothpaste or there simply is no brand available locally so that a user must turn to another alternative to keep his or her mouth fresh and clean. Additionally, perhaps a user does not want to purchase a new one since he or she already has a costly expensive electric one at home. Thus, there needs to be some solution that overcome the aforementioned deficiencies found above in the prior art.
BRIEF SUMMARY OF THE INVENTION
[0008] A disposable toothbrush having a support arm that is connected to a brush head having bristles attached thereto and a toothpaste gel sitting atop a concavity on top of the brush head. There is a thin deformable plastic cap attached to the brush head wherein a thin deformable cap attached to the brush head covers the toothpaste gel so that it is sealed from an external environment. A delivery port formed within the brush head between an underside of the brush head and a top of the brush head adjacent a cavity holding the toothpaste gel. A plurality of delivery ports are formed within the brush head between an underside of the brush head and a top of the brush head adjacent a cavity holding the toothpaste gel. Three delivery ports are formed within the brush head between an underside of the brush head and a top of the brush head adjacent a cavity holding the toothpaste gel. The handle is of the toothbrush is hollow having a support arm that is extendable into the handle.
[0009] A disposable toothbrush having a hollow handle connected to a support arm that is connected to a brush head having bristles attached thereto such that the support arm is extendable into the handle. There is a toothpaste gel sitting atop a concavity on top of the brush head. A thin deformable plastic cap is attached to the brush head such that it covers the toothpaste gel so that it is sealed from an external environment. There is a delivery port formed within the brush head between an underside of the brush head and a top of the brush head adjacent a concavity holding the toothpaste gel. There are a plurality of delivery ports formed within the brush head between an underside of the brush head and a top of the brush head adjacent a concavity holding the toothpaste gel. There are three delivery ports formed within the brush head between an underside of the brush head and a top of the brush head adjacent a concavity holding the toothpaste gel.
[0010] A disposable toothbrush having a handle connected to a support arm that is connected to a brush head having bristles attached thereto and a delivery port formed within the brush head between an underside of the brush head and a top of the brush head adjacent a cavity holding the toothpaste gel. a toothpaste gel sitting atop a concavity on top of the brush head. Also, there is a thin deformable plastic cap attached to the brush head such that it surrounds the toothpaste gel. Further, the handle is hollow and permits the insertion of the support arm therein.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] FIG. 1 a illustrates a back elevation view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge; FIG. 1 b illustrates a front elevation view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge.
[0012] FIG. 2 a illustrates a side cross-section view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge featuring a fully extended handle and arm configuration; FIG. 2 b illustrates a side cross-section view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge featuring a extendable handle and arm configuration.
[0013] FIG. 3 a illustrates an exploded front view of an embodiment of the bristles portion of the toothbrush having delivery ports for expulsion of the toothpaste material; FIG. 3 b illustrates an exploded side view cross section of an embodiment of the bristles portion and the thin deformable plastic cap-paste portion of the toothbrush having delivery ports for expulsion of the toothpaste material with the thin deformable plastic cap not connected to the brush head; FIG. 3 c illustrates an assembled side view cross section of an embodiment of the bristles portion, the thin deformable plastic cap-paste portion of the toothbrush having cavities for expulsion of the toothpaste material with the thin deformable plastic cap connected to the back of the brush head.
[0014] FIG. 4 a illustrates a side view of a hollow handle of an embodiment. FIG. 4 b illustrates a side section view of a thin deformable plastic cap of an embodiment. FIG. 4 c illustrates a section side view of a toothpaste portion of an embodiment. FIG. 4 d illustrates a support arm 105 and associated brush bristle head. FIG. 4 e illustrates a section side view section of the support arm, associated brush bristle head, thin deformable plastic cap and gel in an embodiment where the support arm is in its initial position. FIG. 4 f illustrates a section side view of the support arm, associated brush bristle head, thin deformable plastic cap and gel in an embodiment where the support arm is fully extended.
[0015] FIG. 5 a illustrates a working side view of a user opening the toothbrush of an embodiment. FIG. 5 b - 5 c illustrates a working side view of how a user compresses the toothpaste so as to make the substance flow through the delivery ports in the head of the brush.
[0016] FIG. 6 a illustrates an initial position of the arm support arm side view and FIG. 6 b illustrates the packaging used by the device.
DETAILED DESCRIPTION OF THE INVENTION
[0017] FIG. 1 a illustrates a back elevation view of an embodiment of the Disposable Toothbrush device Having an Internal Toothpaste Cartridge. The toothbrush of FIG. 1 a has three main components, namely, a head having a thin deformable plastic cap 115 , a support arm 105 and a handle 100 . The device of FIG. 1 a is made from plastics for the arm and handle, nylon for the bristles in the head. Rubber is also useable for ergonomic improvement of the handle and heated glue is used to bind the components together. FIG. 1 b illustrates a front elevation view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge. This view again shows the extendible support arm 105 and the ergonomic handle 100 . Additionally, it shows the toothbrush head having three delivery ports 310 found amongst the head's bristles for the expulsion of toothpaste from the thin deformable plastic cap on the other side of the head.
[0018] FIG. 2 a illustrates a side cross-section view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge featuring a fully extended handle and arm configuration. A plastic support arm 105 is integrated with the head and has bristles inserted therein and a thin deformable plastic cap 115 is attached to the back side of the head as discussed below. Further, a toothpaste gel 110 is placed within the thin deformable plastic cap with a dispensing device so as to prepare the thin deformable plastic cap for compression and release of the gel 110 into the delivery ports 310 shown in another figure. A rectangular oblong solid support arm 105 has an integral portion of the same formed as an plastic oblong rectangular solid 215 of greater dimensions in width and thickness than the support arm 105 .
[0019] Additionally, this integral portion 215 has a rectangular locking protrusion 225 that extends outwards from the front face of the integral portion at the bottom of the integral portion 215 . This locking protrusion 225 slides under a corresponding first auxiliary locking protrusion 220 that extends outwards from the inner wall of the ergonomic handle 100 . The first auxiliary locking protrusion 220 holds the support arm 105 in place by sitting atop a ledge formed by the extended locking protrusion 225 as it flows back into the front surface of the integral portion 215 of the support arm 105 . A second auxiliary locking protrusion 230 extends at an angle from the inner surface of the ergonomic handle 100 such that it is wedged underneath the lip of the locking protrusion 225 .
[0020] Finally, the ergonomic handle 100 has a hollow or cavity 235 running down the inside longitudinally so as to permit the extension of support arm 105 along with the integral portion 215 . The device is forbidden from going further by the bottom of the integral portion 215 impacting the inner walls of the hollow cavity 235 as it slopes inwards reducing the dimensions of the cavity; alternatively, the neck of the handle impacting the underside of the tooth brush head. Further, the device is forbidden from extending further by the locking protrusion 225 snapping into a space that hollows out above the second auxiliary locking protrusion 230 and beneath the first auxiliary locking protrusion 220 . FIG. 2 b illustrates a side cross-section view of an embodiment of the Disposable Toothbrush Having an Internal Toothpaste Cartridge featuring a extendable handle and arm configuration as discussed above. Finally, there is a transition from round shaft to square shaft shown in 210 .
[0021] FIG. 3 a illustrates an exploded front view of an embodiment of the brush head 325 including the bristles portion of the toothbrush having delivery ports 310 for expulsion of the toothpaste material; these delivery ports are shown more clearly with regards to FIGS. 3 b - 3 c. FIG. 3 b illustrates an exploded side view cross section of an embodiment of the bristles portion and the thin deformable plastic cap-paste portion of the toothbrush having delivery ports for expulsion of the toothpaste material with the thin deformable plastic cap not connected to the brush head. A thin deformable plastic cap 110 is to be pressed into the head of the toothbrush having a concavity shown in FIG. 3 a that allows for more paste; this thin deformable plastic cap 110 covers the toothpaste gel 315 . FIG. 3 c illustrates an assembled side view cross section of an embodiment of the bristles portion, the thin deformable plastic cap-paste portion of the toothbrush having delivery ports for expulsion of the toothpaste material with the thin deformable plastic cap connected to the back of the brush head.
[0022] The thin deformable plastic cap 110 is connected to the head 325 of the toothbrush through a downwards lip 320 running along the perimeter of the brush head at its bottom edge; this thin deformable plastic cap is connected to the back of the brush head through the use of an adhesive or by being heat treated with a heating element during manufacturing; this fuses the head and thin deformable plastic cap together thereby making a completed device. When a user wishes to expel toothpaste gel through delivery ports 310 all he or she has to do is press down on the back of the thin deformable plastic cap 110 compressing it until the gel is expelled through delivery ports 310 into the bristles. These three circular delivery ports 310 perforate the head 325 of the toothbrush from one side until the other side of the head 325 .
[0023] FIG. 4 a illustrates a side view of a hollow handle 100 of an embodiment. FIG. 4 b illustrates a side section view of a thin deformable plastic cap 110 of an embodiment. FIG. 4 c illustrates a section side view of a toothpaste portion 315 of an embodiment. FIG. 4 d illustrates a support arm 105 and associated brush bristle head. FIG. 4 e illustrates a section side view section of a completed device having the support arm 105 , associated brush bristle head 325 , thin deformable plastic cap and gel in an embodiment where the support arm is inserted as far as possible 400 into the handle. FIG. 4 f illustrates a section side view of a completed device having the support arm 105 associated brush bristle head 325 , thin deformable plastic cap and gel in an embodiment where the support arm is fully extended.
[0024] FIG. 5 a illustrates a working side view of a user opening the toothbrush of an embodiment. A user grasps ahold of the handle with one hand and with the head with another hand. Using both hand the user pulls 500 the head and support arm from its initial position until it opens completely. Then as shown in FIG. 5 b - 5 c, the user compresses 505 the toothpaste 315 so as to make the substance flow through the delivery ports in the head of the brush down into the bristles 510 of the brush head so as to be made useable for brushing the teeth of the user.
[0025] FIG. 6 a illustrates an initial position for a support arm in a side view for a Disposable Toothbrush Having an Internal Toothpaste Cartridge 600 and FIG. 6 b illustrates the packaging 605 used by the device.
[0026] The invention has thus been described in such clear and precise terms as to enable one of ordinary skill in the art to understand its fundamental principles.
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A disposable toothbrush having a handle connected to a extendable support arm that is connected to a brush head. The brush head has bristles attached thereto and a delivery port formed within the brush head between an underside of the brush head and a top of the brush head adjacent a cavity holding the toothpaste gel. This toothpaste gel sitting atop a concavity on top of the brush head. A thin deformable plastic cap is attached to the brush head such that it surrounds the toothpaste gel. Further, the handle is hollow and permits the insertion of the support arm therein.
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FIELD OF INVENTION
[0001] This invention relates to a unique polymer tape, having both adherence characteristics and stretchability, and primarily for use in application and holding furniture and other components together while the woodwork is being glued or otherwise secured into a permanent connection.
BACKGROUND OF THE INVENTION
[0002] Numerous types of glues, clamps, brackets, and other types of holding means have long been available in the art, for holding furniture and other components together, primarily made of wood, but perhaps some plastic, while they are being affixed together, through the use of a glue, into a permanent structure. Obviously, many types of tapes have been available for holding parts together, such as the Scotch Brand tape, which is used for a myriad of purposes. But, normally, that type of tape generally has uses for securing segments together, such as when gift wrapping, and trail ends of the wrapping paper needed to be affixed to the packaging, as prepared. Other types of tapes, such as duct tapes, are available for holding, reasonably permanently, various parts of duct work, and other components together after being secured into a connected relationship.
[0003] The current invention is designed to add another dimension to the use of a highly stretchable tape, having sufficient elasticity, so it can be drapped around furniture, or other wooden components, and hold them together, after or as the parts are being glued and while awaiting its drying or hardening for securement of the furniture components together.
SUMMARY OF THE INVENTION
[0004] This invention contemplates the formation and use of a polymer tape that has some degree of adhesion, but also significant elasticity, and which can be subjected to significant tension, so as to apply a force primarily to furniture components as they are being glued during manufacture, or when being repaired as a result of breakage.
[0005] More specifically, the clamping tape of this invention is a form of a tape functioning as a clamp and wrap, that is designed for wrapping around furniture components, and to hold them into their fastened relationship, until such time as any applied glue or other adhesive sets, or dries, either during furniture repair, or during its manufacture.
[0006] The concept of this invention is to simplify wood gluing with this new style of tape as a clamp concept. It eliminates the need for special clamp designs, clamps that can damage the finish upon furniture components, and secures the wooden pieces together until the adhesive dries. There is no weak bonds or gaps from wood movement, since the wood components are securely held together, until the adhesive binds. There is no real adhesive applied to the surface of the tape, so there is no affect upon the wood surface or finish of the furniture component, when held in place by means of this wrapping concept. Hence, there is no adhesive that needs to be cleaned up, after the furniture components have been securely fastened together. The tape of this invention is a soft silicone type of tape, which is inert to most furniture or other wooden finishes. The tape only sticks upon itself, and does not incorporate any type of superficial adhesive, that can connect onto the furniture surface, and leave any residue marks, or imperfections.
[0007] When gluing furniture parts together, and whether it be during their initial manufacture, or when a repair is made, the gluing application of holding such furniture parts together will be done as routinely performed at the factory, or even by the homeowner, or furniture owner, when repairing the same, and after the glue is applied, the tape wrap of this invention can be stretched, across the wood sections, to tightly adhere them together, into an affixed and permanent condition, while the glue hardens.
[0008] This tape includes inherent stretchability, normally exhibiting up to a 300% elastic stretch, which holds the furniture parts under tension, while the glue dries. Thus, when the furniture is being adhered together, this tape is simply stretched, but not over stretched, around the furniture components, to hold them into a fixed position, once adjusted into the desired and required configuration, and elastically holds the parts in place, until the adhesive secures them into a permanent bond. To hold the silicone tape wrap of this invention in place, it does have sufficient adherence upon itself, so that wrapping the tape around the furniture parts, and onto previously applied sections of the tape, causes the tape to adhere on itself, and hold the furniture parts into a fixed position, until the glue hardens. Once the glue does harden, the tape of this invention can be easily separated from the furniture parts, and simply thrown away, having completed its required work.
[0009] For most shapes of furniture, this tape can simply be stretched around the pieces of the wood, and back onto the tape itself, until such time as the furniture components are adhered into a more fixed position, to allow the adhesive to dry, and hold the furniture parts together, by glue adhesion. This tape only sticks upon itself, and when one applies it to the furniture parts, he/she only must hold the starting end of the tape in place, while stretching the tape around the furniture parts, sufficiently to hold all of the furniture structural components together, into the final configuration, until such time as the glue hardens. Merely a slight pressure of the tape upon itself, as it is secured, will hold it in position about the furniture components, while the glue dries. The furniture parts can be further moved and the tape stretched, to add further glue, or repositioning of the parts, and then released so the tape as stretched will shift the parts back into a desired position.
[0010] For example, when a table/chair leg requires repair, and it may have an unusual shape, which may not accommodate the normal type of clamping mechanical mechanism, one may simply stretch the tape of this invention around the furniture leg, and back onto itself, to secure it and hold it in position, until the applied adhesive dries. This anchors the furniture parts together, and the tape holds upon itself, after it has been stretched around the frame and back onto the furniture components, when applied. One need only to press the tape and onto itself, to fix it in position, to hold the furniture parts together, during repair. Upon the glue drying, one needs only to cut the tape free, and remove it.
[0011] The tape of this invention is a silicone type of polymer tape, it is of a soft texture, it has significant elasticity, as previously reviewed, and the silicone tape only adheres and sticks to itself, but not to the furniture parts. Other glues that are used for holding the furniture structure together, in the event there is any glue residual, does not bond to the silicone tape. Since there are no adhesives integrated into the structure of this tape wrap, there is no other secondary clean up that is required to remove any adhesive, from the tape, or from any furniture finish. And, the advantage of utilizing the tape of this invention is that it works on many unusual shapes of furniture or other wooden components, or even polymer parts, as their previously applied glue dries, which normally such furniture components may not otherwise be held together, by the usual one directional metal clamps, as normally in use.
[0012] The tape of this invention has a tensile strength, as tested, up to 600 psi, and it even is insulative to voltage, up to 400 volts/mil, and only fuses to itself, and holds in position, as applied. During general usage, the tape exhibits no adhesive, it will not melt when used at ambient temperature, it remains flexible even to very low temperatures, and forms an air and water tight seal upon itself, when used for holding furniture structures together. As stated, the tape can stretch up to three times its length, when applied.
[0013] Furthermore, the unique tape of this invention, to assure its adequate functioning, when rolled into its usable form, as marketed, will further include an outer wrap of polyethylene, or other liner, so as to assure that the tape is not adhere upon itself, before usage. When the tape is ready for usage, the outer liner is simply removed, as the tape is stretched and applied, so as to minimize any interference from the liner, or other proximate compositions, when the tape is wrapped about furniture during a repair or manufacturing process.
[0014] It is, therefore, the principle object of this invention to provide a clamping type of silicone tape for use upon furniture and related products during their repair or manufacture.
[0015] It is another object of this invention is to provide a self adhering tape, that adheres on itself, after its outer liner is removed, as during application and usage.
[0016] Still another object of this invention is to provide a clamping tape that can be applied to furniture components by a sole person during repair or manufacture.
[0017] Still another object of this invention is to provide a clamping tape that has elastical stretch up to approximately 300% of its normal state.
[0018] Yet another object of this invention is to provide a silicone tape that can be applied to furniture parts, without tarnishing any surfaces to which the tape is applied.
[0019] Still another object of this invention is to provide a clamping tape that adheres upon itself, during usage.
[0020] Still another object of this invention is to provide a silicone clamping tape that can be used under even extreme conditions, for holding components together.
[0021] Another object of this invention is to provide a tape that does not incorporate any other adhesives, in its structure, when manufactured, or during usage.
[0022] Still another object of this invention is to provide a clamping tape that can be used upon unusual shapes of components or furniture parts so as to hold them into a fixed position during repair or manufacture.
[0023] These and other objects may become more apparent to those skilled in the art upon review of the summary of the invention as provided herein, and upon undertaking a study of the description of its preferred embodiment, in view of the drawings.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0024] In referring to the drawings FIG. 1 shows a perspective view of a roll of the clamp tape of this current invention, showing the tape, with its outer overlaying liner, as rolled upon its core;
[0025] FIG. 1 a is a cross sectional view of the tape showing its angulated contouring;
[0026] FIG. 2 shows a view of a furniture part, with the clamping tape of this invention being applied thereon, for holding furniture parts together during their gluing; and
[0027] FIG. 3 is a partial view of a wooden structure, such as a container or chest, held into position by means of the current tape while its adhesive is drying.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] In referring to the drawings, FIG. 1 provides a view of a roll 1 of the tape of this invention as it is being unrolled, as during usage. The tape includes the silicone polymer layer of tape 2 and has the outer liner of polyethylene or other film 3 laminated therewith, when applied into the roll form, so as to prevent the tape from adhering upon itself, until such time as it is used. The outer polymer liner is applied to the tape as it is rolled onto its core 4 , and remains in that position until the tape is unwound from the roll, and the liner 3 is removed, as the tape 2 is being applied to an item of furniture, or other wooden or polymer components, as they are being glued together.
[0029] As can be seen in FIG. 2 , the tape 2 is shown as it is applied about the pedestal or base 5 of the item of furniture, and designed to add stretchability inherently to it, as it holds the furniture legs 6 in place, as they are glued into position surrounding the table column 7 during its manufacture. The tape, because it is so flexible, can be secured in as many wraps as required to hold the furniture parts in place, during their assembly.
[0030] FIG. 3 shows how the tape 2 can be applied around a wooden box structure 8 and hold it into its formed configuration, during such time as the furniture glue that has been applied at the corners, hardens, for the purpose of making the constructed box more permanent of structure. Usage of the tape under these conditions forms a complete binding of the parts together, and there are no weak bonds or gaps from any furniture movement, during the adhesive drying process. For most furniture shapes, one needs simply stretch the tape around the pieces of the wood, and back onto itself, for self adherence. As the tape only sticks to itself, one only needs to hold the starting end of the tape with a thumb or finger, while stretching the tape around the furniture components, and then wrapping the tape back onto itself, with the application of a slight pressure, to secure the tape into a holding position. After the glue dries, one simply needs only to cut the tape free, and dispose of it.
[0031] As can also be seen for the tape as shown in FIG. 1 , it has a color guideline 9 that runs centrally of its length, and the guideline furnishes a guide for winding of the tape when formed into the roll form, and as it is applied to furniture or other products, during its application, to assure its aligned application onto the parts being repaired. This guideline facilitates the winding of the tape so minimum overlapping is obtained while maximum physical and electrical properties are retained. Also, the tape has a slight triangular configuration, as shown in FIG. 1 a, with the tape 2 slightly bowing laterally of the guideline 9 arranged centrally thereof. The guideline runs generally along the peak of the formed triangle, of the tape, as can be seen in cross section.
[0032] The tape of this invention has dielectric strength of approximately 300 VPM minimum. Its shore hardness is in the range of 50 plus or minus 10, by ASTM D2240 requirements. The tensile strength of the tape, by ASTM D412 standards, is approximately 600 to 700 psi minimum. The temperature range for this formed tape is between about −65° to 500° F. Its resitivity, by ASTM D991 standards, is approximately 13, with a ohm/cm minimum. Its adhesion tackiness, by ASTM standards, No. D2148, is 2 P.P.I. Its military specification is approximately MIL-1-46852C. Type II, A-A-59163. The above properties for the tape are as a guide only, and are not set forth for specification without testing by the user in its laboratory setting.
[0033] As is known, a silicone tape is made from the organic compound generally represented by R SUB 2 SIO, which is analogous to a ketone. It is an organic siloxane. It is part of a large group of polymerized organic siloxanes, that are unusually stable over a wide temperature range, that are obtained as oily fluids, resins, and elastomers converted into greases or other compounds, in this case, into a tape composition. It has a texture of a highly flexible polymer tape, or like a rubber form of tape, which in this particular instance, is for use for holding these furniture and other structural components together, during repair and manufacture.
[0034] Variations or modifications to the subject matter of this invention may occur to those skilled in the art upon review of this invention. Such modifications, if within the spirit of this development, are intended to be encompassed within the scope of the claims of any patent to issue hereon. The depiction of the invention in the drawings, and as explained in the specification, are set forth for illustrative purposes only.
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A silicone tape having inherent elasticity and flexibility to allow for its significant stretching, which when unrolled from its tape roll, and its laminar film removed, can be stretched around the furniture or other componentry to hold it in position until any applied adhesive hardens, during furniture repair or manufacture.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a configuration of mini-volume reaction receptacles of which the housings of each receptacle encloses an elongated chamber that, by its ends, is connected to apertures of the particular housing, and wherein the housings each have the same base surface and are of slight height relative to the base surface and are stacked one above the other while the base surfaces are mutually aligned, and wherein at least one aperture of one receptacle communicates with at least one aperture of a consecutive receptacle as seen in the order of stacking.
2. Description of the Related Art
A configuration of this kind is known from FIG. 6B of WO 96/14934. In this configuration, two receptacles are stacked one on the other within the cavity of a basic housing while subtending a communication passage. The chambers are designed for different purposes of reaction and allow carrying out different reactions on a specimen that, in sequence, is moved first into one of the chambers and then is moved through the communication passage into the other chamber. Such a design allows a number of different applications. For instance, one chamber may be used to purify DNA material and PCR (polymerase chain reaction) may be carried out in the next chamber. As indicated in FIG. 7 of the document, the design may be modified by being fitted with a heater for the PCR chamber.
The known basic design of this housing comprising the stacked array is required to support in place the stack and includes intake and outlet ducts to supply specimen material to the chambers. However, the basic housing also demands substantially large areas exceeding by far the base area of the chamber cases. Moreover, the required basic housing entails substantial increases in costs.
A stacked array of two chambers is known from U.S. Pat. No. 4,902,624, wherein the chambers are received compactly in one common housing. This design allows an array of several tightly adjacent receptacles that may be serviced jointly through the pipette tips of a multiple pipette configured in the conventional grid of a micro-titration tray. The chamber configuration of the US '624 patent is fitted for such purposes with a pipette-accessible aperture at its top.
However, the application of the US '624 patent incurs the drawback of the firmly integrated configuration of the two chambers, thereby constraining use of the two chambers only in a fixed relation. Using the chambers individually or changing, for instance, the sequence of the chambers or the number of chambers required in a given process is precluded.
SUMMARY OF THE INVENTION
The present invention is directed toward a stacked array of the above kind wherein the individual chambers are exchangeable and may be stacked one on the other in the desired sequence while nevertheless making it possible to operate with a compact, stacked array in applications using a multi-pipette.
In the invention, the particular chambers of identical base area that is on the same array of base areas may be superposed on each other into arbitrary heights. The mutual geometric interlock assures fixing the stack in place and, accordingly, a basic housing requiring additional area is not needed. The stack's housings subtend between themselves chamber communications and, as a result, specimens may be sequentially pumped through various chambers for the purpose of implementing consecutive reactions. Each housing is fitted at its top side with an aperture for pipette access, pipetting may be carried out at arbitrary stack heights into the particular uppermost housing. The housings being relatively dismantlable, the individual housings also may be used for individual reactions independently of other housings, or they may serve as preliminary reaction stages in order to allow subsequent further reactions in other chambers. The pipette which shall be set on the uppermost housing may be used to pump specimen liquid through the chambers, wherein the pipette communicating with that chamber that at the time contains a reaction specimen. Accordingly, a small array area with conventional multi-pipette configurations suffices to set up a serviceable stack that may be applied in a highly versatile manner by exchanging or interchanging chambers to the most diverse reactions even including a very large number of reaction stages.
The geometric interlock between the chamber housings may be implemented by special clamps or plug-in devices. Preferably, however, the interlinked apertures themselves act also as plug-in devices, as a result of which housing manufacture shall be substantially simplified and far more economical.
In further accordance with the present invention, the pipette-accessible apertures in the form of recesses together with corresponding protrusions of the above housing may create the plug-in connection, again simplifying manufacture.
As already mentioned above, the housings may receive different chambers for different purposes. One or more chambers may be fitted for PCR purposes. This entails regulated chamber heating which, as in the initial, first-cited documents, may be in the form of a small heating element situated near the chamber. Advantageously, however, if the lowermost reaction receptacle of the stack is used for PCR functions, then it may be conventionally placed on the top surface of a PCR cycler block and be temperature-regulated at its bottom surface, thereby attaining highly effective temperature regulation.
The present invention offers the advantage of a better wall/volume ratio, and this improved wall/volume ratio is advantageous with respect to PCR and also to chambers with wall-bound reagents and furthermore for other purposes. In addition this design of the invention offers the advantage of improved rinsing in the absence of dead corners.
The present invention further offers the advantage of simple manufacture particularly applicable to PCR chambers in order to attain a planar surface allowing good temperature regulation and being thermally highly conductive, for instance by making the tray out of metal. The present invention further provides improved rapid temperature regulation of the entire chamber volume.
In further accordance with the present invention, a chamber is in the form of a narrow duct. On account of the capillarity of the narrow, elongated chamber, the specimen shall be well cohesive, that is it will not tear apart during pumping. Moreover, mixing a specimen may be improved by repeated pumping in both directions.
Further, if the filling aperture is made narrower and, in particular, is made capillary, good suction on the filling aperture will be assured and allows residue-free emptying by suction at the filling aperture.
BRIEF DESCRIPTION OF THE DRAWINGS
These and further features of the invention will be apparent with reference to the following description and drawings, wherein:
FIG. 1 is a longitudinal section along line 1 — 1 of the reaction receptacle shown in FIG. 2 mounted on the temperature-regulating block of a thermo-cycler;
FIG. 2 is a section along line 2 — 2 in the FIG. 1 ;
FIG. 3 is a planar block constituted by several reaction receptacles;
FIG. 4 is a receptacle—used for purifying nucleic acid—in the stacked position on the reaction receptacle of FIG. 1 ;
FIG. 5 is an enlarged detail of the duct of the purifying receptacle of FIG. 4 ;
FIG. 6 is a section corresponding to FIG. 1 of the reaction receptacle shown in a variation for optical investigations;
FIG. 7 shows a further variation in the manner of FIG. 6 ;
FIG. 8 shows a further variation corresponding to that of FIG. 6 ; and,
FIG. 9 shows a stack of FIG. 4 but with three mutually stacked reaction receptacles.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 and 2 show a reaction receptacle 1 comprising a rectangular housing 2 made of an appropriate plastic. A reaction chamber 3 is formed into the underside of the housing 2 in the form of a recess and is covered downward by a metal foil 4 , which is coated with a plastic layer 5 on the side facing the housing 2 . By means of the plastic foil 5 , the metal foil 4 may be bonded to the lower surface of the housing 2 or be joined to it thermally, for instance by hot-sealing. In this manner, the reaction chamber 3 is closed on all sides.
The reaction chamber 3 is in the form of an elongated duct running in a winding or serpentine manner around several bends. At its ends, the duct is open by means of apertures 6 , 7 with respect to the top side of the housing 2 . As shown by FIG. 1 , each of the apertures 6 , 7 is fitted at its upper free end with a recess 6 ′ that, illustratively, may sealingly receive a pipette tip 8 . The reaction chamber 3 may be filled from the pipette tip through the aperture 6 , with the other aperture 7 being used for ventilation.
The reaction receptacle shown in FIG. 1 is used for PCR. Using the pipette tip 8 shown in FIG. 1 , first a specimen containing a nucleic acid to be amplified may be fed into the reaction chamber 3 . Using the same or another pipette tip 8 , the mixture of reagents required for PCR may then be added. Thereupon, thorough mixing of the inserted mixture may be attained by advancing and retracting the mixture in the elongated duct constituted by the reaction chamber 3 . This process is enhanced by the narrow cross-section of the chamber 3 and, furthermore, by turbulence and shearing forces generated at the chamber's bends. As shown by FIG. 2 , the cross-section of the chamber widens at its end that is toward the aperture 7 . This feature also increases mixing.
As shown in FIG. 2 , the chamber 3 is very elongated and exhibits a tiny cross-section that preferably exerts, at least in the vicinity of the intake aperture 6 , a capillary effect on the liquid. As a result, capillarity will keep the liquid together and this liquid remains stressed in the vicinity of the intake aperture, as a result of which it may not only be introduced through the aperture 6 but also be aspirated again by it without residues remaining in the chamber 3 . In this manner, problem-free filling, to-and-fro motion (for the purpose of mixing), and withdrawal through the aperture 6 is feasible.
Moreover, the narrow geometry of the chamber 3 assures that even in the presence of small quantities of introduced liquid, there shall be filling of a segment wherein the liquid coheres in a bubble-free manner and exhibits surfaces only at the front and rear ends of the liquid-filled segment. These surfaces are small and the interfering evaporation arising during raised PCR temperatures is substantially averted.
It must be borne in mind that the entire reaction chamber is planar and situated at a very small distance from the metal foil 4 . As a result, it may be temperature-regulated by the foil.
The metal foil 4 may be heated and cooled in different ways in order to temperature-regulate the specimen in the reaction chamber 3 . Applicable heating may illustratively be direct heating of the metal foil 4 by passing an electric current through it. Furthermore, the shown reaction receptacle 1 also may be directly set on the surface of a Pettier element in order to be selectively heated or cooled by the Pettier element.
However, FIG. 1 shows that the reaction receptacle 1 , together with the metal foil 4 constituting the temperature-regulating surface of the reaction receptacle 1 , is mounted on the surface of a temperature-regulation block 9 of a substantially commercial thermo-cycler. As regards the present purposes, the temperature-regulating block 9 may be a simple flat plate that is very thin and therefore of little heat capacity, whereby the block may act quickly in its temperature regulation. Illustratively, Peltier elements are mounted underneath the temperature-regulating block 9 , of which one element is shown as 10 in FIG. 1 .
The shown planar design of the reaction receptacle 1 is suitable for configuration in juxtaposition with further identical reaction receptacles 1 ′ and 1 ″ on the temperature-regulating block 9 . A lid 11 may be lowered onto the reaction receptacles and force them against the temperature-regulating block 9 to attain improved heat transfer.
FIG. 1 also shows that the reaction receptacle 1 may be fitted with a sealing cap 12 , which is secured by a strap 13 to the housing 2 of the reaction receptacle 1 . The sealing cap 12 is fitted with sealing protrusions 14 , which in a sealing manner may engage the particular recess at the upper end of the apertures 6 , 7 of the chamber 3 in order to seal the chamber. In the closed position the lid 11 may press against the flat top side of the sealing cap 12 .
In a variation of the above described embodiment, the chamber 3 also may assume other geometries, for instance being a round or rectangular planar chamber, care being required that all volume elements of the chamber always must be near the temperature-regulating metal foil 4 . In a variation of the above-discussed embodiment, the metal foil 4 may be eliminated and only a plastic foil 5 may be used which, when very thin, will also offer excellent heat transfer.
On a smaller scale, FIG. 3 shows a topview of the assembly of FIG. 1 and that a substantial number of the rectangular reaction receptacles 1 may be juxtaposed in rows and columns, for instance in the conventional 8×12 configuration of a total of 96 receptacles. As shown by FIG. 1 , these receptacles may be mutually abutting. Such abutting configuration may be assured, for instance, by geometrically interlocking the reaction receptacles. For that purpose they may be fitted at their abutting sides with appropriate protrusions. These receptacles, moreover, are designed to allow stacking them.
FIG. 4 shows the reaction receptacle 1 of FIGS. 1 and 2 in the stacked configuration with a superposed purification receptacle 16 , which is very similar to the reaction receptacle 1 . The receptacle 16 comprises a plastic housing 17 wherein, just as in the reaction receptacle 1 , a purification chamber 18 is subtended at the underside and initially is open. The purification chamber 18 is closed by a plate 10 which, in this instance, need not be a thin foil and which is connected in an appropriate manner to the housing 17 so as to seal it. A purification chamber 18 is subtended in the embodiment in the form of an elongated duct and cross-sectionally resembles the reaction chamber 3 of FIG. 2 .
The plate 19 comprises two downward pointing adapters each fitting into the recess 6 ′ of the apertures 6 and 7 of the reaction receptacle 1 . A duct 20 connected to the purification chamber 18 also communicates with the filling aperture 6 of the reaction chamber 3 and a duct 21 , acting as the venting duct and passing through the housing 17 of the purification receptacle 16 freely upward for ventilation, communicates with the other aperture 7 of the reaction chamber 3 . The other end of the purification chamber 18 not connected to the duct 20 communicates with a duct 22 running to the top side of the housing 17 and comprising at its top side a recess 6 ′ to receive the pipette tip 8 .
The purification chamber 18 is used to purify the nucleic acid present in a specimen to be tested before PCR is carried out. As shown by FIG. 5 , the wall of the purification chamber 18 is fitted for that purpose with an appropriate layer 23 , which is bonded to the wall and which exhibits properties to retain nucleic acid under given, selected circumstances, and to release the nucleic acid under other given, selected circumstances.
The full procedure carried out in the configuration of FIG. 4 may be controlled by the pipette tip 8 . First, the pipette tip feeds the specimen containing the nucleic acids into the purification chamber 18 . Then, the nucleic acids are immobilized in the purification chamber 18 at the layer 23 . Accordingly, the chamber 18 may be purified by introducing and evacuating liquid. Thereupon, and under appropriate conditions, liquid may be supplied to absorb the newly released nucleic acids and transfer them through the duct 20 into the reaction chamber 3 of the reaction receptacle 1 . The reagents implementing PCR may already have been admixed or be post-fed in a second stage from the pipette tip 8 . Thereupon, the reaction chamber 3 is heated and cooled through the foil 4 and PCR is carried out. Next, the product enriched by amplification nucleic acid may be evacuated.
In a variant regarding the housings 2 and 17 shown in FIG. 4 , such housings also may be constituted, for instance, by two mutually merging chambers. The housings 2 and 17 retain the same planar geometry and base surfaces as shown in FIG. 4 in order that they may be stacked with other housings, for instance receiving only one chamber.
After being taken apart, the two housings 2 and 17 of FIG. 4 may also be used alone, in particular the housing 2 receiving the PCR chamber 3 .
Illustratively, the shown receptacles 1 and 16 may be externally rectangular as shown above at a base surface ( FIG. 2 ) with edge lengths of roughly 10 mm and a height ( FIG. 1 ) perpendicularly to the surface of the temperature-regulating block 9 roughly of 1 mm (or a few mm). The total volume of the chambers 3 or 18 may be roughly 20 μltr, whereby specimens of a few μltr may be used.
A stacked configuration of these housings may be configured in the array of FIG. 3 on an array surface and, as a result, stacked configurations may be juxtaposed in the array. The array of FIG. 3 then may be serviced simultaneously by pipette tips 8 also configured in a matching array.
FIGS. 6 through 8 show variations of the reaction receptacle 1 , the reference numerals used heretofore being retained as much as possible.
The reaction receptacle 1 of FIG. 6 corresponds to that of FIG. 1 except for a recess 30 above one of the segments of the chamber 3 . As a result, only a very thin wall of the housing 2 exists above the chamber 3 in the zone of the recess 30 . The entire housing 2 is made of an optically transparent material.
A detection device 31 is shown mounted in such a manner to the reaction receptacle 1 that, by means of an optical transmitter 32 , it irradiates the housing 2 laterally as far as the chamber zone underneath the recess 30 . An optical receiver 33 enters the recess 30 to test fluorescent light in the chamber 3 .
The reaction receptacle 1 may rest on the temperature-regulating block 9 of FIG. 1 and PCR may be carried out in it. The detection device 31 may monitor, by means of appropriate procedures, amplification taking place during PCR.
As regards the embodiment of FIG. 6 , the optical path denoted by the arrows runs at an angle through the housing. This configuration is therefore suitable for fluorescence.
FIGS. 7 and 8 show variations operating on the basis of a straight optical path and therefore being appropriate not only for fluorescence but also for photometric processes.
As regards the embodiment of FIG. 7 , the housing 2 is fitted at its top side with two recesses 34 , 35 situated one on each side of a segment of the chamber 3 . The transmitter 32 and the receiver 33 of the detector device 31 dip into the two recesses 34 , 35 , and, in this embodiment, the transmitter and the receiver point at each other. Accordingly, in this embodiment mode, a zone of the chamber may be irradiated along a straight path and, consequently, optical measurements may be taken in order to monitor reactions in the chamber 3 or to investigate reaction products.
FIG. 8 shows a variation of the embodiment of FIG. 7 . In this instance, the design of the reaction receptacle 1 substantially corresponds to that of FIG. 6 . However, a window 36 has been cut out of the metal foil 4 underneath the recess 30 . In the zone of the window, the chamber 3 is only sealed off by the plastic coating 5 . In this embodiment, the transmitter 32 and the receiver 33 of the detection device 31 are configured underneath and also above the reaction receptacle 1 as shown in FIG. 8 . This embodiment is inappropriate for PCR. However, the reaction receptacle 1 according to this embodiment may be used as a cuvette.
As regards the embodiments of FIGS. 6 through 8 , and provided the design is appropriate, the purification receptacle 16 also may be used instead of the reaction receptacle in order to monitor the progress of purification in the receptacle 16 or to merely use it as a cuvette for appropriate detection purposes.
FIG. 9 shows a stack configuration corresponding to that of FIG. 4 , but in this instance comprising three superposed reaction receptacles. The reaction receptacle 1 situated at the bottom of the stack corresponds to that shown in FIG. 1 or to the lower receptacle shown in FIG. 4 and is used for PCR. It rests on the temperature-regulating block 9 of FIG. 1 .
The uppermost reaction receptacle 16 corresponds to the receptacle of FIG. 4 and is used for DNA purification before implementing PCR. It is fed from the pipette 8 which, after purification, presses the specimen through a transfer duct 40 of the center reaction receptacle 41 toward the PCR chamber 3 of the lowermost receptacle 1 . After the execution of the PCR in chamber 3 of the lowermost receptacle 1 ; the pipette forces the specimen upward into the chamber 42 of the center reaction receptacle 41 , the chamber 42 being, for example, embodied as shown in topview in FIG. 2 . After the specimen has passed through this chamber and after carrying out a scheduled reaction therein, the specimen may be withdrawn again consecutively through all chambers by means of the pipette 8 . At its free end, the chamber 42 communicates through a duct 43 with the venting duct 21 of the uppermost reaction receptacle 16 in order to allow venting during the to-and-fro motion of the specimen in the chambers of the stack configuration, that is, to preclude any backing up.
Again the stack configuration of FIG. 9 may be designed to match the array of FIG. 3 in order that a matching multi-pipette may jointly service several stacks juxtaposed in an array.
As regards special applications, and by increasing the stacking height, further reaction receptacles fitted with special chambers appropriately communicating with each other may be constituted in order to carry out a series of consecutive reactions.
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A configuration of mini-volume reaction receptacles ( 1, 16, 41 ) of which the receptacle housings ( 2, 17 ) each enclose an elongated chamber ( 3, 18, 42 ) of which the ends are connected to apertures ( 6, 7, 20, 22 ) formed in the receptacle housing. The receptacle housings have identical base surfaces and have a small height relative to the base surface, and are stacked on one another while their base surfaces are mutually aligned. At least one aperture of a receptacle housing communicates with at least one aperture of a vertically adjacent receptacle housing, as seen in the direction of stacking. The receptacles ( 1, 16, 41 ) are mechanically interlocked in a direction transverse to the direction of stacking and can be plugged one into another. Each receptacle housing defines at least one aperture ( 6, 7, 22 ) at its top side that is accessible to a pipette.
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FIELD OF THE INVENTION
The invention involves effecting a warp change on weaving machines by the tying of a new warp to the old woven-out warp, the old warp being pulled on its last piece through the harness over a length of approximately 1.5 to 2 m and wound up in order to eliminate cross-overs of the warp yarns and to loosen warp yarns stuck together with size. The old warp is therefore prepared in such a way that the quality of the tying operation is influenced positively and, in particular, knotting can be carried out with straight yarns. When a new warp is being tied, this piece previously pulled forwards is then pulled back again and weaving takes place in a completely normal way after the machine has been started.
BACKGROUND OF THE INVENTION
A parameter which is very important in weaving and which essentially determines profitability is the performance of a machine, a machine group or an entire weaving mill. The machine manufacturers have always made efforts to increase the performance, but these have hitherto, in practice, been restricted only to the avoidance, reliable detection and rapid elimination of machine stoppages. Only very recently has it been acknowledged that the article change and warp change have a relatively high potential for rationalization which can be utilized to increase the performance. Two directions of endeavored are appropriate for this, on the one hand substantial automation and on the other hand such a high degree of simplification that these operations can be carried out by a single person.
The present invention comes within the latter sector and relates to a method and an apparatus for the simplified warp change on weaving machines, on which the end portion of a warp is pulled forwards over a specific length, in which method the warp yarns of the woven-out warp are fixed and cut off by a rail-like member and the warp yarns of the new warp are clamped on a tie-in frame which has clamping members and which is transported to the weaving machine, on which the warp-yarn layer of the woven-out warp is inserted into the clamping members.
These operations are known and have been practiced for a long time, for example in the tying of warps by means of the tying-in machine USTER TOPMATIC (USTER being a registered trademark of Zellweger Uster AG), but this concerns the traditional warp change which is not automated and which, in practice, is usually carried out by several persons. With regard to an automation of the warp change, two proposals have recently been made, these having so-called one-sided clamping rails (Swiss Patent Applications No. 1193/91 and 2741/91) which can be inserted behind the warp-yarn regulator after the old warp has been pulled forwards. After the warp yarns have been clamped, they are cut off just behind the one-sided clamping rail and the clamping rail is then pulled back towards the tying-in frame. This operation requires a driving and control mechanism which involves a relatively high outlay and which is itself relatively expensive.
SUMMARY OF THE INVENTION
A method for allowing a one-man warp change and an apparatus for carrying out this method are now provided as a result of the invention.
The method according to the invention is characterized in that the warp-yarn layer of the woven-out warp is fixed on a roller assigned to the clamping members and is pulled back out of the weaving machine over the said specific length as a result of the rotation of this roller.
The apparatus according to the invention for carrying out this method, with a tying-in frame having clamping members for two yarn layers, includes a rotatable winding roller arranged parallel to the clamping members and having fixing means for the warp yarns, and by a carrier unit for the said winding roller and for the tying-in frame, the said carrier unit preferably being provided for mounting on a warp-beam transport unit.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The invention is explained in more detail below by means of an exemplary embodiment illustrated in the drawings; in these:
FIG. 1 shows a diagrammatic view of a warp-beam transport unit having an apparatus according to the invention arranged on it; and
FIG. 2 shows a section along the line II--II of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows from the side, that is to say as seen transversely to the warp beam 1, a warp-beam transport unit BW which consists essentially of a front and a rear cuboid block 2 and 3, a base 4 connecting the blocks 2, 3 and receiving arms (not shown) for the warp beam 1. The two blocks 2 and 3 contain, among other things, a drive for the warp-beam transport unit and, for transferring the warp beam 1 into the weaving machine, various controls, an operating desk and a respective bore for receiving a supporting column 5. A supporting platform 6 for a tying-in frame 7 and for a winding unit 8 is fastened to the supporting columns 5.
Mounted on the supporting columns 5 are trolleys 9 which are displaceable in the longitudinal direction of the supporting columns 5 and the adjustment of which takes place by means of hydraulic tappets 10 arranged in the blocks 2 and 3. Each trolley 9 carries, on its inside, running rollers 11, between which a running rail 12 is guided; the supporting platform 6 is fastened to the two running rails 12. The supporting platform 6 can be displaced via the running rails 12 transversely to the warp-beam transport unit BW between a transport position and a working position, and can be fixed in these positions. In the working position on the weaving machine, the warp beam 1 is moved out laterally on the side of the warp-beam transport unit BW facing the weaving machine and is inserted into the bearings of the weaving machine. The supporting platform 6, together with the built-on tying-in frame 7 and the winding unit 8, is displaced relative to the operator before the warp beam is inserted.
If a warp-beam diameter of 1.2 m is assumed, then the total width or total depth of the installation in the working position amounts to around 2.5 m, this being absolutely unacceptable for transport purposes in view of the confined conditions of space in the weaving shed. Consequently, for transport purposes, the warp beam 1 and the supporting platform 6 are pushed in the manner of a drawer into the warp-beam transport unit BW, the width of which is then determined by the diameter of the warp beam 1 and, in the chosen example, amounts to 1.2 m.
The supporting platform 6 consists of two plate-shaped sidewalls 13 and a rest 14 which is connected to the sidewalls 13 and which is preferably formed by two sectional rails. To avoid possible jamming or tilting during the adjustment of the height of the supporting platform 6, the connection between the rest 14 and at least one of the two sidewalls 13 is an articulated design. Possible distortions can thereby be compensated. Moreover, the sidewall 13 on the right in FIG. 1 is provided with a perforation, through which the clamping rails of the tying-in frame 7 can be pushed.
FIG. 2 shows, in a cross-section, the tying-in frame 7 and the winding unit 8 and the way in which they are fastened on the sectional rails 14 forming the rest of the supporting platform 6. The tying-in frame 7 is formed by the upper part of a tying-in stand for the USTER TOPMATIC tying-in machine and consists essentially of two pairs of clamping members K1 and K2, between which the two yarn layers to be tied to one another are clamped, of a so-called brush beam 15 for achieving uniform warp-yarn tension, and suitable carriers 16 for the clamping members and for the brush beam 15.
The clamping members K1 on the entry side, that is to say the side on the right in the figure, are formed by two clamps, each consisting of a clamping rail 17 made steel and of a clamping strip 18 made of aluminium. The clamping rails 17 are known from the USTER TOPMATIC. The lower clamping strip 18 is provided with an additional part made of aluminium, so that, as a result of lateral displacement, the desired spacing relative to the upper clamping strip 18 can be set for the clamping operation. After the clamping operation, the spacing shown is obtained by means of a lateral displacement of the additional part.
The clamping members K2 on the exit side are formed by two clamping elements, each having a clamping rail 19 and a clamping comb 20.
First of all, the warp-yarn layer Kn of the new warp beam 1 is clamped in between the lower clamping rail 17 and the associated clamping strip 18, on the one hand, and the lower clamping rail 19 and the associated clamping comb 20, on the other hand, outside the weaving mill. The warp-beam transport unit BW (FIG. 1) is then moved into the weaving mill and brought into the working position, in which, with regard to FIG. 2, the warp beam 1 and, of course, also the weaving machine are located on the right-hand side of the tying-in frame 7.
The old warp Ka now to be clamped on the tying-in frame 7 was likewise prepared, specifically by means of the following operations: the warp was pulled forwards in the region of its end through the harness over a length of approximately 1.5 to 2 m. As a result, an absolutely exact separation and alignment of the individual warp yarns was achieved in this drawn-forward region as a result of the effect of the harness. The old warp beam is then prepared to be transported away, by inserting a clip into the warp yarns at a specific spacing from the back bearer and by subsequently cutting off the warp. This spacing is under no circumstances smaller than the spacing between the winding unit 8 and the clamping member K1 located on the entry side. The warp-yarn layer is then wound round the clip and the roll thus formed is deposited at the back bearer.
Finally, the empty warp beam is transported away, and the warp-beam transport unit BW, together with the new warp beam, can be moved up to the weaving machine and the new warp beam can be inserted into the weaving machine. The upper clamping strip 18 is laid onto the lower clamping strip 18, on which it is fixed by means of built-in magnets.
The winding unit 8, which serves for pulling back the drawn-forward part of the old warp, consists essentially of a frame 21 screwed to the sectional rails 14, two side parts 22 mounted pivotably in this frame, a winding roller 24 which is mounted in the side parts 22 and rotatable via a crank 23 (FIG. 1) and which carries on its circumference a yarn clamp formed by a clamping strip 25, and a brake (not shown) for the winding roller 24. This brake is formed by a steel band which loops round the winding roller 24 and which can be tightened by means of a screw. To prepare for clamping the old warp-yarn layer Ka, the clamping strip 25 is taken out of its groove on the circumference of the winding roller 24 and the latter is rotated until the groove for the clamping strip 25 is located at the very top, as in FIG. 2.
The operator, who, with regard to FIG. 2, stands on the left-hand side of the supporting platform 6 directly in front of the winding unit 8, now grasps the roll deposited at the back bearer and lifts this, as it unwinds simultaneously, over the tying-in frame 7, with the result that the warp-yarn layer Ka is laid over the winding roller 24. The clamping strip 25 is then inserted and the warp is thereby firmly clamped on the winding roller 24. Finally, the warp is cut off in front of the clip and then, as a result of rotation of the crank 23, wound up on the winding roller 24 and thereby pulled back out of the weaving machine. It can be advantageous, before the pull-back, to insert a comb into the warp in front of the warp-yarn regulator droppers in the running direction of the warp yarns during weaving.
When the warp is pulled back over the desired length, this occurring when the end of the piece previously drawn forwards is located at the entrance of the warp-yarn regulator droppers, the brake for the winding roller 24 is then tightened and the latter is fixed. The upper clamping rail 17 is then applied to the upper clamping strip 18, and this can be made easier by a slight reverse rotation of the winding roller 24.
After the warp yarns have been clamped to the upper clamping member K1, the winding roller 24, together with the side parts 22 carrying the roller 24, is pivoted downwards in the anti-clockwise direction, specifically to the level of the frame 21 or below this. Subsequently, as a result of the rotation of the brush beam 15 in the anti-clockwise direction, the yarn tension is made uniform over the entire warp width, and the upper clamping comb 20 is inserted and the clamping of the warp yarns on the upper clamping rail 19 carried out. The warp yarns Ka are then cut off between the brush beam 15 and the clamping comb and are thereafter removed from the winding roller. The latter can be made easier by the previous insertion of a clip between the brush beam 15 and winding roller 24.
After the clamping of the second warp-yarn layer has taken place, the tying-in operation can be carried out. As soon as this is executed, the clamping members K1 are released, the now one warp is tensioned and weaving can begin.
It should be pointed out that the arrangement illustrated in FIG. 1, in which the supporting platform 6 is displaceable transversely to the warp-beam transport unit BW via the trolleys 9, running rollers 11 and running rails 12, constitutes only one of a plurality of possible exemplary embodiments. It is likewise possible to connect the supporting platform 6 to the supporting columns 5 directly and to mount the tying-in frame 7 and the winding unit 8 on the supporting platform so that it can be pulled out in the manner of a drawer.
The operations described can easily be carried out by a single person. This is made possible in that a clip is used, instead of a cumbersome one-sided clamping rail, for unclamping the old warp on the weaving machine, and in that the old warp is pulled back by means of the winding roller 24. The clip is so light that, together with the part of the old warp wound on it, it can be lifted over the clamping frame by one person, and the crank drive of the winding roller, the said crank drive having a suitable gearwheel transmission, likewise requires only one operator.
Moreover, since the operations described are very simple, the method according to the invention leads to a reduction of the time required for the warp change. Since this reduction is achieved at an extremely low mechanical outlay, the method is also economical and results in an appreciable increase in performance.
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An apparatus and method for effecting a warp change in weaving machines involves clamping the warp yarns of a new warp on a tying-in frame by way of clamping members. In addition, the warp yarns of the woven-out warp, the end portion of which has previously been pulled forwards over a specific length, are lifted over the tying-in frame and laid onto a roller assigned to the clamping members. The warp yarns of the woven-out warp are then fixed on the roller and pulled back out of the weaving machine over the specific length as a result of the rotation of this roller. These operations can be carried out by a single person, so that the warp change is simplified substantially. The tying-in frame and roller are mounted on a common carrier which is mountable on a warp-beam transport unit.
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BACKGROUND FOR THE INVENTION
In most installations, solar panels are mounted in fixed positions, where they achieve maximum gain only at the particular time of day and year when the sun's direction matches the panels' normal axes. The mounting of solar panels on sun-tracking systems with one or two tilt axes, known in the art as heliostats, maximizes their utilization over daily and yearly cycles, both by increasing the aperture they present to the sun, and by maintaining a low angle of incidence of light falling on the panel and thereby reducing reflective losses. by maintaining a nearly angle However, at least three economic and mechanical factors limit the widespread adoption of such heliostatic mounts, particular in small rooftop installations: (1) the expense of tracking mounts and electronics; (2) the concomitant service requirements of the same; and (3) vulnerability to extreme weather, and aesthetic drawbacks resulting from the high profiles of existing heliostatic mounts.
The present invention addresses limitations of existing tracking mounts for solar panels through a combination of methods that provide single or multi-axis tracking using an economical yet robust mounting and tracking system and tilts the panel to face the sun when the sun is shining using simple solar-thermal and mechanical means. One embodiment provides the additional advantages of feathering the panel into a flush low-profile position when the sun is not shining or when high winds prevail.
SUMMARY OF THE INVENTION
The invention is a solar panel mount that pivots a panel about one or more tilt axes so as to increase its gain, where the pivoting about each such axis is controlled by one or more solar mechanical means, each having a directionally-selective solar mechanical device that controls its said means' elongation or retraction.
In the first embodiment described herein, the said solar mechanical device comprises levers operated by a thermally-responsive piston with a radiant energy capturer, mounted such that sunlight within a certain angular range with respect to one of the panel's two planes of symmetry heats the solar mechanical device and thereby lengthens it, lifting the adjacent side of the panel.
In the second such embodiment, the said solar mechanical device comprises a radiant-energy-capturing thermally-responsive tension-changing spring mounted such that sunlight within a certain angular range with respect to one of the mount's two planes of symmetry heats the said device and thereby increases its tension, pulling down the adjacent side of the panel.
The two embodiments described herein are also distinguished from each-other by using different means of pivotably mounting the panel assembly upon the base.
The first embodiment uses a pivoting means in which a mounting system constrains a ridge of a pivot frame to rest in a groove of a base frame and thereby forms a fulcrum and coincident tilt axis. It is referred to herein as a ‘fulcrum-lift mount’.
One configuration of this mounting system enables the pivoting of a panel about any of four possible tilt axes—one corresponding to each the panel's four edges. Because most solar panels have a long and a short dimension, the present description distinguishes tilt axes as being either long—corresponding to the panel's long dimension, or short—corresponding to the panel's short dimension. The present description also distinguishes the four possible tilt axes as left and right long tilt axes, and top and bottom short tilt axes.
The mounting system can be configured so as to provide pivoting of a solar panel about any combination of the four possible tilt axes, where pivoting about each operable axis is controlled by a lifter mounted along the side of the panel opposite the tilt axis. The simplest form of the mounting system has a single tilt axis, pivoting about which is provided by a single lifter. The mount required to provide pivoting about two parallel axes, for example left and right tilt axes, is only slightly more complex than that required to provide pivoting about a single axis, requiring little more than the addition of a lifter.
The mounting system that enables pivoting about both the long and short axes of a panel essentially consists of nesting the mechanism providing pivoting about either or both of the long axes within a similar mechanism providing pivoting about either or both of the short axes.
The second embodiment employs a pivoting means wherein the panel assembly is supported upon the base frame through a universal joint situated just under the panel, and atop a shallow peak rising in the middle of base structure. The universal joint, whose pivot axes are parallel to the short middle axis of the panel and the long middle axis of the base, allows the panel assembly to tilt about any axis parallel to the base plane, while not allowing it to twist. This mounting method is referred to herein a ‘rocker mount’.
SUMMARY OF THE DRAWINGS
FIGS. 1 through 8 show forms and variants of the first embodiment, wherein the pivot mount uses a fulcrum-lift system.
FIG. 1 shows two views of a long-axis dual pivot mount tilted up slightly about its right axis.
FIG. 2 shows two views of a long-axis dual pivot mount in the retracted, level position.
FIG. 3 shows an exploded view of a long-axis dual pivot mount.
FIG. 4 shows an assembled and a partially exploded view of a lifter assembly.
FIG. 5 shows four views of a nested long- and short-axis pivot mounts.
FIG. 6 shows the nine operating modes of a nested long- and short-axis pivot mount.
FIG. 7 shows a cross-section and detail section of a nested long- and short-axis pivot mount.
FIG. 8 shows a variant of the first embodiment in whose thermal capture elements are enveloped.
FIGS. 9 through 12 show an instance of the second embodiment, wherein the pivot mount is a universal joint rocker system.
FIG. 9 shows two views of the panel mount in a neutral state.
FIG. 10 shows an exploded view of the panel mount.
FIG. 11 shows four views of the panel mount tiled about both of its pivot axes.
FIG. 12 shows views of the solar mechanical device of the second embodiment, including a cross-section detail.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This detailed description of exemplary embodiments of the invention presents examples of the first and second embodiments. It first presents an example of a fulcrum-lift mount having a dual long-axis pivot mechanism using solar mechanical devices that separably link corresponding sides of the base and panel assembly. It then presents an example of such a mount having a dual long-axis pivot mechanism nested within a dual short-axis pivot mechanism. The second example differs from the first only by the addition of the parts comprising the short-axis pivot mechanism, or lower pivot mount, which supports the long-axis pivot mechanism, or upper pivot mount. Finally, the present description presents an example of a rocker mount having a two-axis pivot mechanism using solar mechanical devices that tensionally link corresponding sides of the base and panel assembly.
Long-Axis Fulcrum-Lift Mount with Piston Actuators
FIG. 1 shows views of a long-axis dual pivot mount in which the panel assembly, consisting primarily of the panel 8 and panel frame 10 , is tilted up slightly with respect to the pivot frame 20 about its right tilt axis 12 . FIG. 1A shows an isomeric view of the assembly, and FIG. 1B shows a view in which the dual tilt axes are perpendicular to the sheet.
FIG. 2 shows two views of the same assembly shown in FIG. 1 but in the retracted, level position. FIG. 2A shows an isometric view of the assembly, and FIG. 2B shows a view in which the dual tilt axes are perpendicular to the sheet
FIG. 3 shows a dimetric exploded view of a long-axis dual pivot mount shown in FIGS. 2 and 3 . The connections of the various major components are described with reference to this figure.
The right pivot straps 26 and left pivot straps 28 are shown suspended between the panel assembly above, and the pivot frame 20 below. When assembled, the pivot straps connect the panel frame 10 to the pivot frame 20 . The right ends of the right pivot straps 26 are anchored in the right pivot fulcrum anchor slots 23 and their left ends are anchored in the right pivot end anchor slots (hidden from view). The left ends of the left pivot straps 28 are anchored in the left pivot fulcrum anchor slots 27 and their right ends are anchored in the left pivot end anchor slots 29 . The pivot straps are composed of a thin flexible material with a high tensile strength such as steel, and are installed into the anchor slots under a slight tension. Because of the configuration of the straps, the panel assembly can be tilted up about the right tilt axis or about the left tilt axis, but not about both axes simultaneously.
The pivoting of the panel assembly about each tilt axis is controlled by the lifters 30 . Pivoting about the left tilt axis is effected by the right lifter, and pivoting about the right tilt axis is effected by the left lifter. The lifters are articulated to the panel frame 10 through the mounting of the lifter pull handles 66 in the pull handle mounts 16 rigidly attached to the panel frame, and are articulated to the pivot frame 20 through the mounting of the lifter push handles 68 in the push handle mounts 22 rigidly attached to the pivot frame. The lifter handles are pivotably mounted in their respective handle mounts, allowing the lifters to tilt as required to accommodate the angle made by the push and pull handle mounts spanned by each lifter.
FIG. 4 shows views of a lifter assembly. FIG. 4A shows a view of an assembled lifter from the side facing the panel, called its front side, and FIG. 4B shows an exploded view a lifter from the side facing away from the panel, called its back side.
The lifter consists of two main subassemblies: the lift engine 32 , and the jack assembly 60 . The lift engine responds to sunlight falling on its absorptive side, shown in FIG. 4A , by elongating laterally, thereby increasing the height of the jack assembly to which it is articulated, and increasing the distance between the pull handle 68 and the push handle 66 .
The lift engine 32 has two main components that move relative to each other along a common axis: the piston assembly 34 and the spring assembly 50 . The piston assembly comprises the piston mount 36 , a thermal fluid chamber 40 filled with a working fluid, the integral radiant energy capture paddle 42 , and a piston and piston rod 46 .
The spring assembly comprises the spring mount 52 , the spring chamber 54 , and the spring (hidden from view). The spring mount ensleeves the piston mount, allowing the piston and spring assemblies to move relative to each other along the common axis of the piston, piston mount, spring, and spring mount.
When the spring and piston assemblies are joined and moved toward each other along their common axis, the spring is forced into compression and the piston is forced into its retracted position. The elevation of the temperature of the working fluid within its chamber produces force on the piston and its rod pushing the assemblies apart, aided by the compressive force of the spring.
The jack assembly 60 comprises four elongate members: two lever arms 62 and two connector arms 64 ; and the pull and push handles 66 and 68 . Each of the arms is built up of two flat plates rigidly connected to each other by a pair of short cylinders, one at each end of the arm. The cylinders of one of the lever arms and one of the connector arms are shorter axially and larger in diameter than those of the other two arms. The arms are pivotably articulated to form a flexible rhombic-shaped assembly through the concentric mounting of the cylinders of adjacent arm ends with the larger- and smaller-diameter cylinders acting as bearings and journals, respectively.
The pull and push handles 66 and 68 are pivotably articulated with the lever arms 62 and the connector arms 64 , respectively, through the concentric mounting of the short pegs extending from the upper portion of each handle within bearings formed by the interiors of the smaller-diameter cylinders at the top and bottom of the rhombic arm assembly, respectively.
The lift engine is articulated with the jack assembly through the mounting of short lateral pegs 48 and 58 integral to the piston mount 36 in holes within tabs 63 of the plates of one lever arm and the mounting of short lateral pegs integral to the spring mount 52 in holes within tabs 63 of the plates of the other lever arm. When piston and spring mounts are forced apart through the heating of the working fluid in the fluid chamber, the tabs of the opposing lever arms are forced apart thereby forcing the rhombic lever assembly to elongate in the vertical direction.
Each lift engine is mounted so that its radiant energy capture paddle will collect sufficient heat to elongate its associated jack assembly only when the angle formed by the direction towards the sun and the direction from the panel's center toward the lifter parallel to the panel's surface is obtuse.
The front side of the energy capture paddle shown in FIG. 4A is designed to capture sunlight as heat energy, whereas the back side of the paddle shown in FIG. 4B is designed to reflect sunlight. The invention contemplates a variety of methods for making the front surface of the paddle absorptive and the back surface reflective, including coating the back side with a reflective and/or thermally insulating material and coating the front side with an absorptive and/or thermally conductive material. The energy capture paddles pictured in the figures have back sides polished to have a reflective finish and front sides covered with narrow groves parallel to the paddles' long axes and coated with a flat black enamel. The groves on the paddles' front sides prevent the reflection of light from the paddles' surfaces even when the light has a low angle of incidence relative to said surfaces.
Because the lift engine exploits thermal energy to generate mechanical force, it produces elongation of its lifter that is a function of several factors relating to heat transfer including: the incidence angle of directional sunlight with respect to the front side of the radiant energy capture paddle, the ambient temperature, the velocity of ambient air, and thermal conduction through the assemblies connected to the lift engine. The preferred embodiments are designed such that the lift engine's elongation behavior is highly sensitive to direction of incident light, while having limited sensitivity to the ambient temperature, is inversely responsive to high winds, and is thermally insulated from other assemblies.
The invention contemplates several methods of making the lift engine relatively unresponsive to variations in ambient temperature within the normal range of such temperatures encountered in the mount's operating environment. The primary such method is to design the energy capture paddle to have sufficient gain that, when its front sides is illuminated by sunlight, it elevates the temperature of its associated fluid chamber well above the normal range of ambient temperatures, and using a working fluid whose primary expansion range is also above that normal temperature range. For example, given maximum illumination, the paddle might raise the temperature of the working fluid by 80 degrees F., and the working fluid might have a primary expansion range of 110 to 120 degrees F. A lift engine with such characteristics could function over an ambient temperature range of about 40 to 110 degrees F.
A second method of decreasing the sensitivity of the lift engine to variations in ambient temperature consists of enclosing at least the piston assembly portion of the lift engine in an insulating envelope whose front side is transparent, as described below with reference to FIG. 8 . By reducing convective heat losses from the lift engine, such an envelope could increase the range of ambient temperatures over which the engine could operate.
The lift engine is inversely responsive to high winds in that heat captured by the radiant energy capture paddle is lost by convection when the lift engine is bathed by rapidly moving air produced by high winds. This effect is exploited to produce the desirable behavior of lowering the panel into its retracted, low-profile position in the event of high winds that might damage the assembly in a pivoted position. The shape of the paddle and/or its enclosing envelope can be designed to determine the wind speed above which convective heat losses cause the mount to retract its panel. For example, the envelope could have small fins or perforations that would allow significant cooling airflow over the paddle within it only when the wind speed exceeds 50 MPH.
Combined Long- and Short-Axis Fulcrum-Lift Mount with Piston Actuators
The combined long- and short-axis fulcrum-lift pivot mount essentially nests the long-axis pivot mount described above within a second, or lower, pivot mount, with its own pivot frame, pivot straps, and lifters, where the lower pivot mount is oriented perpendicular to and shaped slightly differently from the original upper mechanism.
FIG. 5 shows four views of the combined long- and short-axis pivot mount, where the panel and panel mount is pivoted up about its right tilt axis 12 to near its maximum tilt, and the upper pivot mechanism is pivoted up about its top tilt axis 112 to near its maximum tilt. The four views, in clockwise order, show the mount from its upper left side, its lower right side, its right side, and its bottom side.
Like the preceding figures, FIG. 5 shows the components of the upper pivot assembly, including the panel 8 , the panel frame 10 , the right pivot straps 24 , the left pivot straps 28 , the upper pivot frame 20 , and the side lifters 30 . In addition FIG. 5 shows the components of the lower pivot mechanism, including the top pivot straps 124 , the bottom pivot straps 128 , the lower pivot frame 120 , and the end lifters 130 .
The end lifters 130 of the lower pivot mechanism are identical to those of the upper pivot mechanism 30 , except that the pull and push handles of the end lifters 166 and 168 are longer than those of the side lifters 66 and 68 . The longer handles of the end lifters position their lift engines higher relative to their handle mounts than is the case with the side lifters, compensating for the lower relative positions of the end handle mounts, and for the shadows produced by the tilting of the panel and panel frame by the upper pivot mechanism.
FIG. 6 shows the nine operating modes of the combined long- and short-axis pivot mount in the form of a table having three columns and three rows. The left, middle, and right columns show the upper pivot mechanism pivoting about the left tilt axis, not pivoting, and pivoting about the right tilt axis, respectively; and the top, middle, and bottom rows show the lower pivot mechanism pivoting about the top tilt axis, not pivoting, and pivoting about the bottom tilt axis, respectively.
FIG. 7 shows a cross-section of the combined long- and short-axis pivot mount where both the upper and lower mechanisms are in the retracted position. The upper illustration shows the assembly from the left, the middle illustration labeled SECTION A shows the indicated cross-section through the middle of the assembly, and the lower illustration labeled DETAIL B shows the indicated detail view of the cross-section. Because the cross-section bisects the side lifters 30 , it primarily reveals details about the upper, long-axis pivot mechanism.
The section views bisect the pull and push handles 66 and 68 , showing how their short lateral pegs are mounted co-axially within the cylinders of the lever arms 62 and connector arms 64 . The lower ends of the pull and push handles incorporate rods, seen in cross-section in FIG. 7 , that are mounted in the pull and push handle mounts 16 and 22 , respectively. The rod of the push handle 68 seen in DETAIL B is coaxial with the right tilt axis 12 . As a result, when the panel assembly pivots about the right tilt axis, the said lifter pivots in the same manner, maintaining its geometric relationship with the panel.
Variants of the First Embodiment
The dual long-axis pivot mechanism described above provides pivoting of the panel about the parallel left and right tilt axis, and the combined dual long-axis and dual short-axis pivot mechanism described above provides pivoting of the panel about each of the parallel left and right tilt axis, and about each of the parallel top and bottom tilt axes. Other configurations of the embodiment can be used to provide pivoting about different subsets of the possible pivot axes. The replacement of a lifter along one of the mount's sides or ends with a bracket holding the adjacent pull and push handle mounts in proximity will disable the mechanism's pivoting about the axis on the mount's opposite side or end, while allowing pivoting about the tilt axis that is coaxial with the lower push handle under the action of the lifter on the mount's opposite side or end. Such a modification saves the expense of a lifter and reduces the profile of the mount at the expense of elimination the panel's ability to pivot along one axis. However, depending on the orientation of the platform upon which the mount is installed, pivoting about a given tilt axis may have limited utility. For example, a mount installed on a roof slope facing the southeast would gain very little from pivoting about the long axis on its east side, but would benefit greatly from pivoting about the long axis on its west side. Such an installation would be a good candidate for a long-axis pivot mount having lifters only on the mount's east side, providing pivoting about the tilt axis on its west side.
Another variation of the embodiments described above involves using mount that has only a short-axis pivot mechanism, eliminating the long-axis pivot mechanism. This variant is generally less useful than the single short-axis pivot mechanism shown in FIGS. 1 through 3 , because, for a given height provided the lifter, the panel pivots through a smaller angular range. Another variant involves inverting the nesting order of long-axis and short-axis pivot mechanisms in a mount that combines pivoting about the perpendicular long and short axes, nesting the short-axis pivot mechanism atop the long-axis one.
Variant of the Piston Lift Engine
FIG. 8 shows a variant of the lift engine used in the first embodiment, in which the lift engine is enveloped by a shell 260 . FIG. 8A shows a view of a lift assembly whose lift engine is equipped with said shell, and FIG. 8B shows a diametric view of a fulcrum-pivot mount equipped with two said lift engines.
The lift engine 232 is modified compared to the variant previously shown 32 to have a more symmetric overall shape, and to provide points around its periphery at which to firmly mount the shell. The shell has a transparent front side 262 and an opaque, reflective back side 264 .
The said shell surrounds most of the lift engine but has the cut-out 266 to accommodate the articulations of the lever arms to the lateral pegs integral to portions of the lift engine. The cut-out also enables the exchange of air between the interior and exterior of the shell, at a rate that is proportional to wind speed.
The shell functions in several ways to enhance the mount's performance. The primary such function is to decrease the sensitivity of the lift engine to ambient temperature conditions while retaining its responsiveness to high wind conditions.
The said decrease in sensitivity to ambient temperature results from the insulation between the lift engine and the ambient air provided by the shell and the air trapped within it. This feature provides for more effective solar heating of the engine's front side in cold ambient conditions, while shading the engine's back side.
The said responsiveness of the lift engine to high wind conditions results from the design of the shell's cut-out to induce significant air exchange between the shell's interior and exterior and significant air flow around the engine when and only when the shell is bathed by wind. The cooling of the lift engine provided by such wind-induced convection causes the engine and its associated jack to retract, lowering the panel into its flush low-profile position.
A second benefit provided by the shell is to increase the incident light upon the panel at certain times by reflecting light from the shell's front side to the panel when that light strikes that side with a high angle of incidence. This feature exploits the property of transparent materials having a smooth surface wherein they transmit most light whose incidence angle is less than some threshold and reflect most light whose incidence angle is greater than a similar threshold.
Dual-Axis Rocker Mount with Solid-State Actuators
FIG. 9 shows two views of a dual-axis rocker mount in which the pivot frame assembly is in its balanced position, such as occurs either when the sun is not shining or when the direction of sunlight is perpendicular to the mount's base. FIG. 9A shows a view from above the mount, and FIG. 9B shows the mount's underside.
FIG. 10 shows an exploded trimetric view of the mount, in which all of the major assemblies are dis-assembled into their constituent parts.
The two-axis rocker mount comprises three rigid components that move relative to each-other, not counting solar mechanical devices: the pivot frame assembly, comprising the panel frame 312 , struts 316 , and axle bearing sleeves 318 ; the base frame assembly, comprising the base frame 322 , struts 326 , and axle bearing sleeves 328 ; and the cross axle 330 . The said cross axle has two pairs of co-axial cylindrical surfaces, where the axes of the two pairs are perpendicular to each other.
The cross axle is mounted within the said bearing sleeves to form a universal joint whose one pivot axis is parallel to the short middle axis of the panel, and whose other pivot axis is parallel to the long middle axis of the base. This arrangement allows the pivot frame to pivot about two perpendicular intersecting axes relative to the base, while preventing it from twisting. The struts of the base frame assembly form a shallow elongate pyramid, while the struts of the pivot frame assembly form a shallower, inverted elongate pyramid. This arrangement efficiently distributes gravity loads from the pivot frame through the universal joint and to the base frame. The relatively short distance between the panel center and the pivot axis intersection provides the necessary clearance for components of the lower frame assembly relative to the panel when the pivot frame tilts to its maximum extents, while keeping the center of gravity of the pivot frame and panel relatively close to each other.
The midpoints of each of the four sides of the said panel frame are tensionally linked to the midpoints of the corresponding sides of the said base frame by solar mechanical devices in the form of thermal spring assemblies 350 . Each said thermal spring assembly comprises a radiant energy capture spring 352 , an upper spring handle 360 , and a lower spring handle 370 .
FIG. 11 shows four views and a detail magnification of a panel mount tilted about both of its pivot axes to nearly its limit of travel. FIGS. 11 A, B, and C show the mount from the three axes of the base frame, and FIG. 11 D shows an isometric view of the same. As can be seen in this figure, the thermal spring assemblies accommodate several axes of displacement and tilt between the surfaces of the pivot frame and base frame to which they articulate.
Details of the articulation of the thermal spring assemblies to the frames can be seen with references to FIGS. 10 , 11 , and 12 . The upper spring handle 360 has the integral joint peg 364 which is pivotably mounted in the axle hole 314 of its respective pivot frame member, and the integral spring hinge axle 362 which is pivotably mounted in a loop formed by the top of the spring. In a similar fashion, the lower spring handle 370 has the integral joint ball 374 which is pivotably mounted in the ball socket 324 of its respective base frame member, and the integral spring hinge axle 372 which is pivotably mounted in a loop formed by the bottom of the spring. The flexible mounts of the upper and lower handles differ in that the upper handle allows rotation about one axis relative to its articulating frame member, and the lower handle allows rotation about multiple axes relative to its articulating frame member.
FIG. 12 shows three views of the thermal spring assembly, and a detail view. The operation of the spring, instances of which in different states of elongation can be seen in FIG. 11 , can be understood with reference to the detail view in FIG. 12 . The spring is formed of a flat piece of material with alternating bends and loops at each of its two ends designed to articulate with the said handles. The spring's surface is treated or painted so that its outward-facing side effectively absorbs solar radiation. The radiation absorbed by the spring, and therefore its temperature, increases as the direction of the sun approaches the spring's outward-facing side face.
The spring, when not attached to a load, changes its length in response to changes in temperature such that its length varies in inverse proportion to its temperature. This behavior is achieved by exploiting different thermal expansion coefficients of different materials. In the present embodiment, the body of the spring 354 is formed of a metal such as aluminum, and the convex sides of the springs periodic bends are laminated with a second material 356 having a very high thermal expansion coefficient. When the spring is heated, the expansion of the second material relative to the base material forces the bends to decrease in radius, thereby shortening the overall length of the spring.
Among the methods contemplated by the invention for increasing the degree to which the shape of the spring responds to variations in temperature is the use of laminating materials that have anisotropic thermal expansion characteristics. For example, a polymeric material with a very high intrinsic expansion coefficient might have a microscopic structure in which fibers or plates of a material with a low expansion coefficient run perpendicular to the material's surface, thereby preventing significant expansion of the material perpendicular to that surface and amplifying its expansion parallel to the surface.
When such a thermally responsive spring is attached to a load by tensionally connecting two points, as is the case in the spring pivot embodiment, it exerts a tensional force that is proportional to is temperature, where that tension is alleviated by the movement of the load that shortens the spring.
SUMMARY OF FEATURES OF THE EXEMPLARY EMBODIMENTS
The invention is a mounting system for solar panels that pivots the panel to decrease the difference between the panel's normal direction and the direction of sunlight. This orienting function, which is similar to that provided by conventional heliostats, is provided in the present invention through the use of solar mechanical devices that change shape in response to changes in solar illumination of certain of their surfaces.
Advantageous characteristics of the first exemplary embodiment described herein include the following:
1. When the sun is not shining, the mechanism retracts the panel into its frame such that the entire assembly has a low profile, with the surface of the panel parallel to the platform supporting the mount. 2. The mount provides robust support for the panel despite consisting of parts that are generally thin and light, and using a relatively small quantity of materials. 3. When the mount is subjected to sufficiently high winds, the mechanism retracts the panel into its frame, even when the sun is shining, minimizing the assembly's profile. 4. The mount can be configured to provide pivoting about any subset of the four possible tilt axes corresponding to a panel's four edges, and equipped with only the lifters and other components required by the operable tilt axes.
Advantageous characteristics of the second exemplary embodiment described herein include the following:
1. The mount provides robust support for the panel despite consisting of parts that are generally thin and light. 2. The solar mechanical devices are entirely solid-state and simple in construction.
The foregoing specification describes several exemplary embodiments of the invention. Those skilled in the relevant fields will be able to recognize numerous other configurations, variations, and embodiments of the invention disclosed herein.
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A solar panel mount that tilts the panel about one or more axes toward the direction facing the sun when it is shining, through the action of one or more mechanical means, each effecting tilt about at least one of the axes, and each responding to a particular direction of sunlight with respect to the base or panel, through directionally-sensitive solar radiation absorbing means. In one set of preferred embodiments the mechanical means are length-changing actuators in which a temperature-responsive working fluid drives levers to lift a side of the panel. In a second set of embodiments, the mechanical means are tension-changing actuators in which temperature-responsive folded springs retract to pull the panel to a side.
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FIELD OF THE INVENTION
The present invention relates to a novel method for connecting a printed electronic circuit board to a heat sink. More particularly, this invention relates to a novel method for bonding an RF amplifier circuit board to a metal substrate.
BACKGROUND OF THE INVENTION
Problem
Printed electronic circuit boards are constructed of one or more layers of electrically insulating material. In RF (radio frequency) applications, the insulating material is conventionally a teflon glass or silicon non-conductive sheet. Each sheet is typically penetrated by vias and has electroconductive circuit paths applied to the sheet face, often connecting and including the vias. The electroconductive circuit paths are conventionally silk-screened on the non-conductive sheets and are typically of copper composition. The vias penetrating the non-conductive sheets provide a pathway whereby copper, solder or other conductive materials can penetrate from one electroconductive circuitry layer to another. The various layers are stacked one on top of another. To construct multi-layered boards, the two inner-most sheets are float soldered to one another, the next outer sheets are then float soldered to the previously soldered pair and so forth to create a multi-layered board. The board is then populated with components on its upper surface appropriate to the function and purpose of the circuit board. Mounting of components may be by either surface mount adhesives or soldering, both techniques well known in the art.
Certain circuit boards, notably those including an amplifier circuit, create heat during operation which must be dissipated in some manner to avoid degradation of the circuitry and, potentially, component failure. In an RF amplifier, the RF circuit board has certain zones commonly known as DC traces which must be electrically isolated from the metal heat sink pallet, while other components and circuitry paths require both an electrical and a mechanical bond with and the metal heat sink pallet. Typically the pallet is constructed of aluminum or copper.
Several conventional solutions exist for bonding, electrically and mechanically, the circuit board sheets to the metal heat sink pallet--mechanical connection, adhesive connection and solder connection.
Mechanical connection can be achieved by drilling mating holes in the circuit board and the pallet. Screws are inserted and screwed down to lock the circuit board to the pallet. While an acceptable mechanical connection may result, the screws occupy areas of the circuit board which could otherwise be used to route circuit paths or install components.
Adhesive connection can be achieved by applying an electrically conductive adhesive, such as a silver-filled conductive epoxy, on the mating surface of the pallet and pressing the circuit board in place. The adhesive technique suffers from several shortcomings. Since pressure must be applied to set the board in the adhesive against the pallet, there will be some flow of the adhesive which can result in an undesired electrical connection in one area of the board and/or the flow of the adhesive into vias which affects subsequent population of the circuit board. Moreover, an adhesive connection can loosen over time from thermal stress as the circuit board cycles through heating and cooling transitions during use. Also, the adhesive remains soft, allowing the circuit board to shift position with respect to the pallet.
Conventional solder connection uses "solder buttering" of the pallet which requires that the pallet be heated on a hot plate and maintained at a temperature sufficiently high to keep solder applied to its mating surface in a liquid state. The pallet is coated with solder flux to prepare the surface and the solder is "buttered" on the surface using a soldering iron, spreading the solder until the entire surface is coated. The pallet is assembled to the circuit board by placing the circuit board on the pallet and reheating the pallet until the solder melts and alloys to the circuit paths of the circuit board. With the techniques currently known in the art, this process is far from clean, which this description might otherwise imply. Because of the method of application of the solder to the pallet, there is often excess solder which will flow from between the circuit board and pallet which must be disposed of. Likewise, because the solder coating is uneven, additional solder must often be added along the circuit board and pallet interface edges so that it can wick between the pallet and board where insufficient solder was applied in the initial buttering. Additional difficulties arise at the time the assembly is populated. If the circuit board is populated with electronic components which are to be soldered in place, in commercial manufacture this is accomplished in a reflow oven which melts the solder paste applied to the board surface permitting it to flow into the vias to hold the pieces. Detrimentally, the reflow oven likewise heats the solder between the pallet and the circuit board which can result in the solder connection being weakened; in the solder flowing into areas where it is not desired; and in the pallet and circuit board shifting position with respect to one another.
There is therefore a need in the art for a method of attaching circuit boards to pallets which is easily accomplished, can be easily incorporated into a board manufacturing process, that provides an accurate, reliable, long term bond between the pallet and the circuit paths of the circuit board, and which is unaffected by subsequent solder reflow operations on the assembly.
Solution
The above problems are solved and an advance is made over the prior art in accordance with our invention wherein a novel approach is taken to provide a connection between circuit boards, notably RF boards, and pallets.
In accordance with one aspect of the invention, the pallet is electroplated with the bonding metal to provide an even layer of bonding consituent.
In accordance with another aspect of the invention, the bonding metal is a tin/lead solder having a higher melting point than the solder used in subsequent assembly operations, notably in populating the board with components.
In accordance with still another aspect of the invention, the pallet is machined prior to plating to remove sections of the pallet which are not to contact the circuit board;
In accordance with yet another aspect of the invention, the mating surfaces of the circuit board and the pallet are accurately positioned with respect to one another thru use of a fixture.
In accordance with yet still another aspect of the invention, the circuit board and pallet are pressed against one another are held in close contact throughout the solder bonding.
In accordance with a still further aspect of the invention, a fixture applies pressure against the circuit board at locations where good adhesion between the circuit board and the pallet are of particular interest.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross section of an RF circuit board constructed using the instant invention.
FIG. 2 is a top view of a pallet which has been machined such that it does not contact the circuit board in the machined regions.
FIG. 3 is a bottom view of an RF circuit board which would mate with the pallet of FIG. 2, indicating areas which are not to be bonded to the pallet.
FIG. 4 is a front perspective of the bonding fixture of the preferred embodiment in which a pallet and circuit board are mounted for tin bonding, showing also the nitrogen bath introduction and hot plate.
FIG. 5 is an exploded perspective of the alignment fixture of the preferred embodiment shown in FIG. 4 showing the pallet and circuit board prior to insertion and the drilled spring cavities in the body base.
FIG. 6 is an exploded perspective of the alignment fixture of the perferred embodiment shown in FIG. 4 showing the pallet and circuit board inserted onto the alignment pins of the alignment fixture.
FIG. 7 is a cross section taken along 4--4 in FIG. 4 showing the spring-loaded studs in the extended position controlled by tightening the base plate against the frame.
DETAILED DESCRIPTION
According to the instant invention, reliable bonding and uniform adhesion between a circuit board and a pallet are achieved while avoiding the problems inherent in the prior art processes. This is accomplished, in our inventive process, by coating the pallet with a uniform layer of metal which has a melting point higher than that of the metals to be used in subsequent operations on the circuit board and pallet assembly; and causing bonding between the circuit board and the pallet to occur while there is a strong mechanical connection between them by pressing the two together during alloying of the pallet coating to the circuit board coating. Further discussion will focus on a common two-layer RF circuit board bonded to an aluminum pallet, although the technique is easily applied to other boards and pallets.
As shown in FIG. 1, in one embodiment, an RF circuit board 10 has a Teflon/glass substrate 11, such as Arlon DiClad 880, available through ARLON's Materials for Electronics Division, Rancho Cucamonga, Calif. This substrate has a dielectric of 2.7 which lends itself to RF applications where signals not only follow circuitry but also emanate through the board and pallet. To assist in the creation of uniform adhesion in the bond between the circuit board 10 and the pallet 30, the substrate is flat. In the preferred embodiment, the substrate sheet 11 has a flatness of 0.050 inch/inch.
Electric conductor circuit paths 20, as shown in FIGS. 1&3, are created on the circuit board substrate 11. Summarizing a technique known in the art, the substrate 11 is clad with copper 20 and the clean and dry board is silk screened with resist to identify the conductor paths to be formed. The board is subjected to an etchant such as ferric chloride to dissolve away the unwanted copper 20 not coated with resist to form the conductor paths. In certain applications, the copper paths 20 are coated with other conductive metals, such as solder, tin or gold 22. This additional metal coating 22 over the copper paths 20 is conventionally applied by silk screening a mask over areas not to be coated, then applying the tin, solder or gold as a paste which is melted in place. Alternatively, the additional conductive metal 22 can be electroplated or applied by a metal bath against the copper circuit path 22. As is known in the art, the additional conductive metal 22 can be limited in application to a desired portion of the copper circuit path 20 by masking those areas where the metal 22 is not to be applied.
As shown in FIG. 3, the prepared circuit board 13 is cut and drilled to create vias 24 to permit population with electronic components and positioning against the pallet 30.
With RF amplifiers, certain components, notably power transistors, are placed in contact with the pallet 30 which functions as a heat sink for the components. To accommodate this, the circuit board is drilled and the hole 28 milled to the proper configuration as is shown in FIG. 3 to accommodate insertion of the power transistors through the board 10 to contact the pallet 30 in wells 34.
In the preferred embodiment, the circuit board 13 is drilled to create datum holes 26. The location of each datum hole 26 is accurately controlled by fixturing (not shown) to locate each hole on the circuit board so that it can be aligned with mating holes in the pallet 30 and permit insertion about and capture of the alignment pins 52 when the circuit board is placed in the bonding fixture 50 as shown in FIGS. 4-7.
As shown in FIG. 3, in the preferred embodiment, the underside of the circuit board on which the circuit paths 20 have been etched is cleaned, a coating of tin 22 is selectively applied over the copper electric conductor circuit paths 20 and a solder mask (not shown) is applied to those areas which are not to be soldered to the pallet 30.
In the preferred embodiment, the pallet 30 is aluminum, formed to the desired configuration through any of a number of operations such as extrusion, die forming and machining. Copper and other materials may also be used to produce pallets. Before pallet 30 is coated, it is machined, for example by a milling operation (not shown), to create recessed zones and areas 32 which are not to contact the circuit board, and to create wells 34 for location of power transistors. Thus, zones 32 are created for RF transmissions through the pallet and wells 34 are created for heat absorption by the pallet without electrical connection. In the preferred embodiment, the pallet 30 is drilled to create datum holes 31. The location of each datum hole 31 is accurately controlled by fixturing (not shown) to locate each hole on the pallet so that it can be aligned with mating holes in the circuit board 10 and permit insertion about and capture of the alignment pins 52 when the pallet 30 is placed in the bonding fixture 50 as shown in FIGS. 4-7.
In the innovative approach of the instant invention, rather than using a solder buttering technique to apply solder to the pallet, in the preferred embodiment, the pallet 30 is electroplated to achieve a uniform coating of metal plating 36.
Alternatively, other methods which assure a uniform coating, such as dipping, could be used. In the preferred embodiment, the metal plating 36 is 40% tin/60% lead solder. The solder plating 36 is created in the electroplating process by use of a 40% tin/60% lead solder annode, or a suitable number of pure tin and pure lead anodes to produce the desired ratio, and a fluoboric acid or sulfonic acid bath based 40%/60% tin/lead, or other suitable alloy, the alloy plating bath containing various chemical grain refiners and additives. One such bath is the FluoFree®MR tin/lead plating bath available from MacDermid, Inc., Waterbury, Conn. with appropriate adjustments to obtain the desired alloy, e.g. 40/60 tin/lead.
The electroplating technique entails cleaning and washing the aluminum pallet 30 in preparation for electroplating; submersing the pallet 30 in an electroplating tank containing the appropriate electroplating solution along with the appropriate metal anode(s); and applying an electric current between the cathode and anode(s). In the preferred embodiment, the resulting plating finish produced on the pallet 30 is a fine grained, matte, uniform deposit, although bonding is possible using a bright or dull plating finish. Plating thickness is controlled by controlling the amount of electric current which is applied and the length of time current is applied in the electroplating process. While plating is discussed as applied to the entire surface, it is to be understood that plating can be limited to areas of interest on the pallet surface. Thus, if desired, plating can be limited to just the pallet surface which is to contact the circuit board circuit paths.
In the preferred embodiment, the solder plating 36 has a thickness of 0.0003 inches or greater. Plating thickness is dependent upon the surface finish of the pallet 30 because, in the electroplating process, plating deposits tend to build up more quickly on the peaks than in the valleys of surface scratches while, in the alloying process, the plated metal tends to flow off the peaks into the valleys of surface scratches. So that alloying is uniform across the pallet surface, the minimum plating thickness of the solder plating 36 must be sufficient for plating deposits to remain on the peaks after flowing into the valleys during the soldering operation. In instances in which the surface finish of the pallet is very smooth, for example, where the pallet is formed by stamping, it is possible to reduce plating thickness more, although 0.0002 inches seems to be a prudent lower limit even in such instances.
In the novel approach of the instant invention, differences in melting points for pure tin, pure lead, and solder alloys in creating metal bonds in successive solder-type bonding operations create a superior technique and result for circuit board assembly.
In conventional circuit board bonding, a 60% tin/40% lead solder is used for all bonding operations, including not only the initial bonding of the circuit board to the pallet but also the subsequent bonding of components on the circuit board/pallet assembly. The instant invention uses alloys or pure metals in circuit board/pallet bonding which have relatively higher melting points than the alloys or metals used in subsequent assembly operations to avoid compromising the bond between the circuit board and the pallet. Pure tin, lead or any tin/lead alloy which has a melting point higher than that of 60/40 solder as the bond material between the circuit board and the pallet will not melt at the working temperatures of 60/40 solder used in subsequent assembly operations. Because 60/40 solder has a melting point of approximately 187.8 degrees Centigrade (C.), 370 degrees Fahrenheit (F.), while pure tin has a melting point of 232.8 degrees C., 451 degrees F. and any solder alloy having a tin component of 40% or less has a melting point of 237.8 degrees C., 460 degrees F., or higher, use of pure tin and/or 40/60 solder in bonding the circuit board 10 to the pallet 30 provides a temperature buffer of forty-four degrees C. between the working temperature of the 60/40 solder and the lowest temperature at which bond integrity between the circuit board and the pallet becomes a concern.
In the preferred embodiment of the instant invention, 40/60 solder is used as pallet plating 36 and pure tin is the metal plating 22 over circuit paths 20, which in combination are the alloying/bonding agents between the circuit board and the pallet. 60/40 solder is used in subsequent component assembly operations on the bonded circuit board/pallet assembly, although solders having a higher tin content can also be used.
While the several Figures show the pallet 30 and the circuit board 13 as the same size, this is not necessary to the practice of the invention. The pallet 30 can be larger than the circuit board 13 and vice versa, provided that the mounting area on the pallet 30 is plated and that it is of a size sufficient to satisfy the heat dissipation needs of the components and paths associated with the circuit board 10 to which the pallet 30 is joined. Likewise, the bonding fixture 50 is reconfigured to accommodate the disparate sized components.
Returning to the process of bonding the circuit board 10 to the pallet 30, the plated and machined pallet 30 is cleaned and flux applied (not shown). Flux can be applied to either the pallet 30 or the circuit board circuit paths 20, but in the preferred method, flux is applied to the pallet 30 since it remains upright throughout subsequent operations.
The instant invention has found that bond adhesion is significantly improved by holding the pallet 30 and the circuit board 10 in close proximity to one another during bonding and has further found that alignment between the circuit board and the pallet, often critical to proper operation of the completed circuit board assembly, is improved by mechanically maintaining the position of the components during bonding. These findings are implemented through an innovative bonding fixture hereafter described. Alignment fixture 50 in its preferred embodiment is comprised of a body 54 having a flat base surface 62, and a mounting channel 63 which extends the length of the opposite face defined by two end walls 56 each having a bracket 58 which forms an inverted ledge 60 at the distal ends of which are alignment pins 52. As illustrated by the exploded view of FIG. 5, and the cut-away shown in FIG. 7 taken along line 4--4 of FIG. 4, a plurality of drilled spring cavities 64 extend into body 54 in operative interaction with with a drilled pressure pin bore 66 having the same centerline as the spring cavity. A pressure pin 68 having a cylindrical shaft 70 and a cylindrical, saucer-shaped head 71 is disposed in sliding relation within the bore 66 and spring cavity 64, respectively. The pin shaft 70 has a relatively flat or blunt tip 74.
A base plate 76 has a mounting face 78 which conforms in topography to the body base surface and has a plurality of drilled spring cavities 80, one such spring cavity being shown in the cutaway of FIG. 7 taken along lines 4--4. of FIG. 1. Also residing in each spring cavity 80 and extending into each spring cavity 64 in body 54 is a spring 81 in operative sliding relation with the pin head 70 captured within the body spring cavity 80. While FIGS. 4-7 illustrate the spring cavities and pressure pins as distributed about the alignment fixture in a symmetrical pattern, this illustration has assumed that the primary adhesion points of interest for the circuit paths 20 also are distributed in a similar pattern so that pressure, while fairly uniformly applied across the circuit board surface is also localized at or near the areas where bonding is to occur between the circuit board circuit paths 20 and the pallet plating 36.
As shown in FIG. 6, base plate 76 is removeably attached to body 54 by a plurality of threaded screws 82. By screwing home the threaded screws 81 into body 54, base plate 76 is moved in closer proximity to body base surface 62 causing the captured springs 81 in each spring cavity 80&81 to press against the pin head 70 forcing the pin shaft 72 to translate along bore 64 to penetrate and stand proud of the surface of the mounting channel 63 when the base plate is tightened home against the body. In the fully tightened assembly of the fixture components, the pins will exert, in the aggregate, approximately 200 pounds pressure per square inch against the surface of a circuit board captured within the fixture.
As shown in FIGS. 4-7, insertion of the components into the alignment fixture is accomplished by first relieving pressure on the pressure pins 68 by backing off the screws 82 threaded into the body 54 allowing the base plate 76 to move away from the body, releasing pressure on the springs 81 and permitting the pressure pins 68 to translate a distance into the spring cavity 64 sufficient for the circuit board 10 and the pallet 30 to be inserted between the endwalls 56 and onto the alignment pins 52 without interference. The pallet 30 and circuit board 10 are assembled with the surfaces to be bonded against one another, with the pallet 30 the outermost of the two, then placed against the opposing alignment pin ledges 60 with alignment pins 52 penetrating the respective datum holes 31 to align the circuit board 10 with the pallet 30 in the mounting channel 63. With the circuit board 10 and pallet 30 so positioned, the screws 82 are tightened to draw the base plate 76 against the fixture body 54 causing the springs to force the pressure pins 68 toward the base of the spring cavities 64. With this translation of the pressure pins 68, the pin shaft tips 74 contact and press against the upper surface of the circuit board 10 causing the circuit board to mechanically contact and remain in close proximity to the pallet 30.
With the pallet 30 and circuit board so assembled in the alignment fixture, the pallet is placed on a hot plate 90, as shown in FIG. 4, heated to a temperature sufficient for melting and alloying to occur between the pallet plating 36 and the metal 22 on the portions of the circuit paths which are not masked. In the case of the preferred embodiment which utilizes 40/60 solder as the pallet plating 36 and tin as the metal 22, the operating temperature of the hot plate will be at least 460 degrees F. As the pallet 30 is heated, in the preferred embodiment, a nitrogen gas bath (not shown) is introduced into the mounting channel 63 to retard oxidation during the soldering process. Additionally, the vias 24 in the board 13 prevent gas build-up at the interface of the pallet 30 and the circuit board 13. Once the pallet is raised within the proper temperature range, the tin 22 and solder 36 change state and begin to flow at which time the flux (not shown) conditions the circuit paths 20 coated with tin 22 which facilitates the occurrence of alloying and bonding to occur between the solder 36 and the circuit paths 20 coated with tin 22. This occurs between 260-300 degrees Centigrade in the preferred embodiment. The temperature is held in the stated range for approximately 30 seconds to permit proper tin and solder melt and alloying. Once the pallet 30 is sufficiently heated to cause melting and alloying of the pallet plating 36 with the metal layer 22 over the circuit paths, the alignment fixture with the captured components are removed from the hot plate and allowed to cool. In the preferred embodiment, cooling is promoted by blowing chilled air (not shown) over the assembly.
Upon removal of the now bonded circuit board and pallet assembly from the alignment fixture, the assembly is populated with components, with power transisters being located in the heat sink wells 34 of the pallet 30 and other components in their appropriate positions in the vias 24 on the circuit board. The components are soldered in position using, in the preferred embodiment, 60/40 solder. By controlling the heat within a reasonable range of that required to melt the 60/40 solder, the integrity and uniform adhesion between the circuit board and the pallet remains unaffected.
The integrity of the bonding technique is reflected in the efficiency of the completed RF amplifier unit. The efficiency of RF amplifiers is measured as the ratio of power in to power out of the circuit in watts. Using prior art connection techniques, including adhesive connection, mechanical connection and solder bonding, the average efficiency of a typical RF amplifier unit ranged between 42% and 44%. With the bonding technique of the instant invention, the average efficiency for the same amplifier rose to 49%, indicating a significant improvement which must be attributed to the superior bond between the circuitry and the heat sink without degradation of the unbonded zones critical to RF capability.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.
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A method of joining a metal heat sink pallet to a circuit board by electroplating a layer of solder on the mounting surface of the pallet, placing and holding the circuit board metal circuit paths firmly against the plated mounting surface of the pallet and heating the pallet until the solder melts and alloys with the circuit paths. A nitrogen gas bath is used to inhibit oxidation during heating and alloying and a flux is used to promote alloying. A bonding fixture accurately positions the circuit board with respect to the pallet and applies pressure in circuit path areas of interest during heating, alloying and cooling to accurately position the circuit board on the pallet and to promote a superior mechanical and electrical bond between the circuit paths and the pallet.
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This application is a national phase of International Application No. PCT/GB2011/050046 filed Jan. 13, 2011 and published in the English language.
FIELD OF THE INVENTION
This invention relates to a hanger.
BACKGROUND OF THE INVENTION
Existing hangers for garments generally comprise a base member that is generally horizontal, when in use, and this mimics shoulders in the case of tops and jackets. Alternatively, the horizontal base member is used to support trousers, skirts and shorts either at the waist band, often supported by a clip mechanism, or by folding the garment and resting it on the member, especially in the case of trousers.
Various disadvantages exist with such hangers. For example, the neck of a top may be sufficiently wide for the garment to slip off the hanger, especially if the garment is not put perfectly in the middle of the base member. Therefore, various different lengths of horizontal member are required and the right size must be chosen to avoid the garment falling off the hanger. Furthermore, fashion dictates some lower-body garments are not enhanced by having fold lines, especially in the case of jeans or casual trousers. Therefore, it becomes a disadvantage to have to hang such garments in a way that creases may be formed. Also, if the user folds lower body garments badly before resting them on the hanger in a folded position, a double crease may form in the garment which is unsightly.
It is also the case that people are often lazy and do not take the time to fold their garments or hang them on a hanger with a horizontal member. Instead they put them in a drawer or on a shelf in an unfolded manner, creating creases in undesirable positions, making the wearer look untidy when they next wear the garment.
Further disadvantages occur with existing hangers both before the items are put on display for sale and after. For example, once clothing is delivered to a store, staff members have to take a considerable amount of time to unpack the items, put them on hangers and apply security tags. This process, especially the application of a hanger may need to be repeated each time a person tries on a garment, therefore taking up more of the sales assistant's time.
A further problem with existing systems is that the security tags often result in putting a hole in the item, albeit a small one, which may damage the item. Also, the security tag can catch on shelving or on people and their accessories and cause further damage to the item, especially when a potential customer is trying the item on.
High-end fashion items can be of considerable value and therefore it is desirable to avoid putting security tags on the clothing. However, should these items be stolen from a store, the losses may be significant.
SUMMARY OF THE INVENTION
According to a first embodiment, the present invention provides a device for hanging an item comprising a support-engaging portion and a deformable elongate member, the elongate member comprising a connection mechanism such that the elongate member can be deformed back upon itself and connected to itself to form a loop in such a way that when the elongate member is in its deformed state, a substantially flat spacer is defined at the intended lower end of the loop so that the item rests upon the flat spacer when in use.
By making a hanger to such a construction, the connecting member forms a loop that becomes substantially held in place. Many items of clothing, especially garments intended for the lower body comprise loops, often in the form of belt-loops. For casual trousers, for example jeans, it is preferably to not have folded or pressed creases in the garment. Therefore by hanging the trousers by way of a hanger threaded through itself to interlock with the belt-loop and being connected to itself, the casual trousers can be hung on a rail without causing undesirable creases. Therefore, the hanger can be substantially connected to an item by threading the attachment portion through the item, for example a belt loop or a hanging loop, and using the connecting member to form a substantially unreleasable loop. The item can then be hung on a support, such as a standard retail clothing rail, using the support engaging portion.
Clothes, including many jackets and coats, often comprise a hanging loop for hanging the garment on a coat peg or coat stand. The present invention may be threaded through such a loop and the garment hung using that loop. Furthermore, the washing instructions label or ‘size’ label is often positioned at the back of neck on jumpers and other tops. The hanger may be threaded through those labels if there is not an intended hanging loop. In addition, sheets, cloths, gloves, hats, shoes, scarves and other items can be hung from the hanger.
Because a flat spacer, or shelf, is introduced to the hanger, the garment can rest on the spacer without deforming the material of the garment. For example, a belt loop can lay flat on the spacer, thereby reducing the risk of the loop deforming and damaging the material.
Such a device, or hanger, can be attached to clothing articles during manufacture, thereby reducing the amount of labour required by staff in a clothes store, because there is no need for them to attach hangers because as they unpack the clothing and put them directly on the shelves or rails using the pre-attached hanger.
The attachment portion may be connected to the support engaging portion via a body portion. By connecting the attachment portion to the support engagement portion via a body portion, space is provided on the hanger for application of a logo or an indication of the size of the item. Also, the hanger is more robust and aesthetically appealing when a body portion is present.
It is preferably that the elongate member comprises at least one pre-determined weakened region. By having pre-determined weakened regions, the elongate member may be deformed in a particular way so as to form, for example a triangular loop, on which garments may be hung. The weakened regions make the loop easier to deform, thereby requiring less effort by the user. Additionally, the flat spacer can be more readily be formed when the elongate member is provided with pre-determined weakened regions. Furthermore, the shape of the loop may be designed to relieve pressure on the connection member by forming a loop of a particular shape.
Advantageously, the engaging portion is in the form of a hook. Hooks are particularly compatible with standard retail clothing rails, and make putting the hanger on a rail or peg relatively easily. Alternatively, the engaging portion may be in the form of a loop. Hotels reduce the risk of hangers from being removed from the room by connecting a loop to a rail and having a detachable hanging part. By using a hanger according to the present invention and having a loop, the hanger does not necessarily need to be disconnected from the rail in order to hang a garment.
It is preferably that, the device further comprises at least one security tag. Because the device attaches to an item in a non-releasable fashion, incorporating a security tag within the device allows for the device to be used in existing clothing stores to reduce the risk of items being stolen. Additionally, the amount of labour required to put clothing out for sale is reduced by allowing for the hanger and security device to be attached at once, rather than having to attach them separately. Indeed, the security device and hanger may be applied by the clothing manufacturer, as mentioned above. Furthermore, there is no need to put a hole in the garment in order to attach the security device, thereby reducing the risk of the garment being damaged during application and removal of the security tag.
In one embodiment, the security tag is attached to, or at least partially embedded in, the Hanger. Once the hanger is made, a security tag can be attached using adhesive. A recess may be left in the device to allow the security tag to be partially embedded and ‘centred’ so that the security tag is always in a predetermined location on the device,
It is preferable that the security tag is wholly embedded within the device. This prevents parties from physically tampering with the device. Furthermore, by wholly embedding the security tag, the tag is hidden from view and one might assume that there is no security tag on the device. If the device is moulded from plastics materials, the security tag may be moulded into the device during manufacture.
Advantageously, the security tag is part of an electronic article surveillance system and wherein the type of tag is selected from a list comprising: magnetic (or magneto-harmonic) tag; acousto-magnetic (magnetostrictive) tag; radio-frequency tag; and microwave tag.
Alternatively, the security tag is microchip. By using a microchip, the device can provide more information, for example, the name of the owner of the hanger.
Preferably, the device may be adapted to be tracked by CPS technology to determine its location. For high-cost items it is desirable to be able to track the location of the hanger that is attached, in case the item is lost or stolen. By using known GPS technology, the device can be located.
It is advantageous if the attachment portion comprises reinforcement means to resist severing of the attachment portion. In order to reduce the risk of one removing the hanger from an item, reinforcement means can be used. By using reinforcement means, the likelihood of the device being removed in-store is reduced as a customer will have more difficulty in removing the device.
Preferably, the reinforcement means comprises metal wire embedded within the attachment portion. Metal wire, for example steel wire, is a cost effective method of reinforcing the device. Scissors are less likely to be able to cut through the device, thereby making it more resistant to removal by a thief.
In one construction, the connection mechanism is a substantially releasable connection, and, advantageously, the releasable connection is a snap-fit connector. It is preferable that the releasable connection is a snap-fit connector. By using a snap-fit connector, the loop is readily, quickly and easily releasable.
Alternatively, the connection mechanism may comprise a substantially unreleasable, nr permanent, connection.
In one preferred embodiment, the connecting member comprises a split-click fastener mechanism. The mechanism may be a hemi-spherical, or ‘mushroom’ topped, click-fastener with a split through the middle the hemi-spherical top. The top of the click-fastener is compressed together as an aperture is threaded onto the fastener. Once the aperture is over the top, or ‘mushroom head’, of the click-fastener, the ‘head’ or top expands outwardly again, preventing the aperture from passing back over the fastener, thereby making it substantially non-releasable. The head of the fastener may then be covered or concealed to prevent one from being able to readily attempt to compress the fastener and pass the aperture over the top once more.
Alternatively, the connecting member comprises a ratchet mechanism. Using a ‘cable-tie’ or ratchet mechanism provides a cost-effective and simple to operate one-way connecting member. The receiving portion may be concealed to prevent one from attempting to release the teeth and reverse the connection.
The device may comprise a plurality of elongate members. By having more than one elongate member, multiple garments may be hung from a single hanger. In a construction having two elongate members, the members may be in the form of an inverted ‘Y’ shape, with the two elongate members having an appreciable gap between them. Such a hanger may be used to hang a single garment, for example by being threaded through two belt loops of a pair of jeans. The garment is then more secure and can be better displayed, but, when the connection mechanism is substantially releasable, the garment remains readily releasable from the hanger.
The invention extends to a method of hanging a garment comprising the steps of:
threading a hanger as claimed in any preceding claim through a loop connected to a garment;
closing the releasable connection mechanism; and
using the engaging portion to hang the garment.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which;
FIG. 1 shows a front view of a hanger according to the present invention;
FIG. 2 shows a back view of the hanger of FIG. 1 ;
FIG. 3 shows a side view of the hanger of FIG. 1 ;
FIG. 4 shows a side view of the hanger of FIG. 1 , when in use;
FIG. 5 shows a second embodiment of the present invention; and
FIG. 6 shows a front view of a third embodiment of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
FIGS. 1 to 6 show a hanger 10 having a hook portion 12 connected to an intended upper end of a body portion 14 , and an elongate member 16 connected to an intended lower end of the body portion 14 . The length of the elongate member 16 is approximately the same as the length of the combined body portion 14 and hook portion 12 . The elongate member 16 has a male part of a one-way ‘snap-fit’ connector 18 at the end 20 , nearest the body portion 14 . The end 22 farthest from the body 10 of the elongate member 16 has an aperture 24 , which is designed to cooperate with the ‘one-way’ snap-fit connector 18 . The elongate member 16 is weakened in a transverse direction in three positions 26 a , 26 b and 26 c . The hanger 10 further comprises a region 28 on the body portion 14 on which a logo or identifying means can be printed or written. The hanger 10 is bevelled at both the end of the hook portion 12 and the end of the elongate member 16 . The hanger 10 is constructed from a plastics material.
When in use, the elongate member 16 of the hanger 10 is threaded through a belt-loop of a pair of jeans (not shown). As shown in FIG. 4 , the elongate member 16 is then folded inwardly at weakened positions 26 a and 26 b and outwardly at 26 c , so that the aperture 24 is in line with the connector 18 . The section between weakened positions 26 a and 26 b defines a flat spacer 27 . The aperture 24 is pushed onto and engages the male snap-fit connector 18 . The male snap-fit connector 18 yields while the aperture 24 is pushed onto it due to the split in the top of the snap-fit connector 18 . Once the aperture 24 has passed over the snap-fit connector, the plastics material returns to its original position and the aperture 24 is prevented from passing back over the snap fit connector 18 . Therefore, the aperture 24 and the snap-fit connector 18 make a non-releasable connection such that the jeans are held securely on the hanger 10 and the ‘loop’ formed by the elongate member 16 hanger cannot be readily uncoupled. The hook portion 12 of the hanger 10 can then engage a hanging rail (not shown), with the item to be hung resting upon the spacer 27 .
To remove the item from the hanger 10 , the elongate member 16 must be cut, preferably along one of the weakened regions 26 A 26 b 26 c.
FIG. 5 shows a hanger 10 having the features shown in the first embodiment in FIGS. 1 to 4 , with the additional feature of a recessed area 30 of the body 14 opposite the arc of the hook portion 12 . When in use, the hook portion 12 engages a rail and the recessed area 30 reduces the risk of inadvertent disengagement of the hanger 10 . When the hanger 10 is raised in order to be disengaged from the rail (not show), the user must draw the hanger 10 away from the rail in order to effect disengagement. If the user does not draw the hanger 10 away from the rail and continues raising the hanger 10 , the recessed area 30 will engage the rail and make it more difficult to remove the hanger 10 from the rail. Therefore, if the hanger 10 is unintentionally raised with respect to the rail, recessed area 30 will reduce the risk of disengagement of the hanger 10 .
FIG. 6 shows a further embodiment of the present invention, wherein a split snap-fit connector 18 is positioned on the body portion 14 of the hanger 10 . In this embodiment, a loop of metallic wire 32 is provided within the hanger 10 to reduce the likelihood of the hanger being easily removed from the item to which it is attached.
In order to remove the hanger 10 from the item to which it is attached, a removal device (not shown), such as a guillotine, is used to cut the plastics material, preferably at 26 a or 26 b , allowing the hanger 10 to be removed from the item. Alternatively, the removal device may melt the plastics material of the hanger 10 and any reinforcement material so that the hanger 10 can be removed from the item. The removal device may be mounted to a surface near a cashier's desk so that once an item has been paid for, the hanger 10 and integral security device can be removed prior to the customer leaving the store. By using a surface mounted device for the removal of the hanger, the likelihood of a thief removing the hanger in-store is reduced.
As shown in FIG. 6 , a security tag 34 is moulded into the hanger during manufacture and is wholly embedded within the body portion, thereby sealing it within the hanger.
The connector 18 shown in the Figures may be releasable, or ‘two-way’, rather than unreleasable. The hanger can then be reused and is suitable for use domestically. Where the connector 18 is a releasable connector, the item is removed from the hanger by releasing the connection and removing the elongate member 16 from the item.
Variations and modifications to the illustrated construction may occur to the reader familiar with the art without taking the device outside the scope of the present invention.
The hook portion 12 may be replaced with a closed aperture so that the hanger can be threaded onto a rail and retained on the rail. Such a construction may be useful in a hotel, where clothes hangers are often retained on a hanging rail to prevent theft of the hangers.
The body portion 14 may comprise a magnetic portion, either in addition to or in place of the region 28 , so that a metal plate can be attached to the hanger 10 . The magnetic plate may contain a name, address, or an identifying number. Such a construction may be useful for identifying garments, for example coats in a cloakroom or garments in a dry-cleaner. Alternatively, a magnetic plate may be used on a metal hanger. This allows items to be identified quickly and easily from a rail and is more easily read than a label attached to the hanger either by sticky tape or string.
Other connection members may be used in place of a snap-fit connector, for example, a hook and eye fastener, a ‘popper’ a button and hole, etc.
The wire in FIG. 6 of may be a length that passes from the snap-fit connection member 18 to the aperture 24 , rather than a loop. This maintains the resistance of the elongate member against being cut, but requires a shorter length of wire.
“Loop” is intended to mean a closed circuit but not necessarily a circle.
“Electronic article surveillance” (EAS) is terminology used in the art of security devices. EAS is a technological method for preventing shoplifting from retail stores or other establishments whereby tags are fixed to merchandise and/or objects. The tags are removed or deactivated by the staff upon the item being properly bought or checked out. At the exits of the establishment, a detection system sounds an alarm or otherwise alerts a member of staff when active tags pass through.
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The present invention discloses a device for hanging clothes, comprising an engaging portion and a deformable elongate member, the elongate member comprising a connection mechanism such that the elongate member can be deformed back upon itself and connected to itself to form a loop.
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This application is a continuation-in-part application of the U.S. patent application Ser. No. 08/277,469 entitled "Multi-Purpose Dolly-Truck" by Richard G. Stich, filed Jul. 20, 1994, now abandoned that is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
This invention generally relates to an apparatus and method for conveying objects and in particular to an apparatus and method for conveying a bucket of, for example, liquid for short distances with rolling motion of a dolly and over small obstacles with tilting motion of a truck.
BACKGROUND OF THE INVENTION
Buckets of various sorts are utilized for numerous activities and can have a bail type handle. Some common uses of such buckets are for holding paint, dry wall joint compound, chemicals, food, plastics, asphalt, tar, farm feed, and cleaning fluids. When buckets are emptied of material, they are commonly used for holding water, other liquids, tools, nails, screws and other small parts. Such buckets are commonly carried by hand, sometimes physically straining the neck, shoulders, forearms, back, and/or wrists, of the persons carrying the buckets.
To transport such buckets, dollies with caster wheels are used in the prior art. A caster wheel is a wheel mounted to permit the wheel to swivel freely. Caster wheels permit short distance rolling movements of a dolly. Using a dolly, a bucket can be moved on a floor without lifting or tipping the dolly.
One disadvantage of prior art dollies is that a dolly can convey an open bucket only on a smooth floor. Any drag or any obstacle such as extension cords, stairs and sudden floor elevation changes will stop the dolly's motion and can spill a liquid contained in the bucket being carried by the dolly. Moreover, a dolly's front wheels cannot be raised to, for instance, go over an extension cord. Going up or down stairs with a dolly is also difficult because the swiveling nature of caster wheels frequently results in one wheel facing the stairs while another wheel is in a different position, which can, in turn, result in dragging. To negotiate such obstacles, the dolly and bucket both have to be carried over the obstacle.
Also in the prior art, hand trucks are used to transport buckets. A typical prior art hand truck has a handle and a pair of non-swiveling, parallel truck wheels on which the hand truck can be pivoted. Using a hand truck, a sealed bucket can be lifted from its upright position and moved in a tilted position and over obstacles such as extension cords and stairs.
Although a hand truck can negotiate obstacles, a hand truck cannot easily be rolled along a floor (in an upright position) as necessary for short distance movements in cases where work commonly starts and stops (such as, for example, painting hallways, maintaining hardware, moving containers around a kitchen, cleaning with mops in the bucket, vacuuming a floor and dispensing liquid on a driveway). Moreover, a hand truck cannot convey open containers of liquid because the liquid can spill when a hand truck is tilted. Liquid sloshed out of an open bucket can land on the floor and be conveyed by the wheels or cause the floor to be slippery and thus dangerous.
SUMMARY OF INVENTION
In accordance with this invention, a single apparatus called a "dolly-truck" is provided which has caster wheels for short distance rolling movement of an object in an upright position as well as truck wheels for moving the object in a tilted position over obstacles such as stairs. Thus, the dolly-truck has the versatility to be used as a dolly and can be tilted back to be used as a hand truck. The dolly-truck provides a very stable mechanical structure for moving objects such as open or closed buckets, various kinds of barrel containers, and five-gallon open containers.
The dolly-truck of this invention has a body with caster wheels mounted at a sufficient distance from the body center to provide stability to the dolly-truck. In one embodiment of this invention, the dolly-truck body includes a retaining structure (such as a wall, called "retaining wall") to hold the object being transported in place during movement of the dolly-truck. The retaining structure has a height of at least one half the height of the object thereby to retain the object during movement of the dolly-truck.
In a variation of this embodiment, a retaining wall of the dolly-truck has holes so that labels on the object are visible. In another variation of this embodiment, the retaining wall includes a retaining ring typically but not necessarily at the top of the retaining wall with knobs (called "retaining knobs") which permit the object to be securely fastened to the dolly-truck. The retaining wall and the ring have closed circular shapes in one embodiment and open shapes in another embodiment. The open shapes allow an object to be moved through the opening, thereby eliminating the need to lift the object over the retaining structure during e.g. removal of the object from the retaining structure. The open shapes can form half a circle (i.e., semicircle) or a larger portion of a circle than the semicircle. In one variant, the retaining structure substantially encircles the object except for a slot that accommodates a pump mounted on the object. In still another variant, the retaining structure has a varying height, wherein a portion (called "front portion") having the smallest height also eliminates the need to lift the object over another portion (called "rear portion") having the largest height of the retaining structure. A retaining ring is openable in one embodiment with a portion, called "closure member", that can move (e.g. slide or pivot) with respect to the retaining wall, as described below.
The dolly-truck preferably has a handle which is adjustably attached to the dolly-truck body. In one specific embodiment, the handle is frictionally supported in extension tubes of the retaining wall. The handle can be raised or lowered, depending on the height of the user. Depending on the embodiment, adjustment knobs or a wing nut when tightened, prevent the handle from moving either up or down in the extension tubes while the dolly-truck is being utilized. The handle is used by a user to roll the dolly-truck in an upright position along a floor and also to move the dolly-truck in a tilted position over obstacles.
The handle has a brace for stability. In one embodiment, the brace has a concave cylindrical surface which permits two or more buckets (either filled or empty) to be stacked one on top of the other and be simultaneously moved by a single dolly-truck. In one variant of this embodiment, the brace has one or more clips that can hold two objects (e.g. a basket of tools and a lid) simultaneously, thereby reducing the cost (as compared to using two types of clips to hold the two objects). If the handle interferes with any given process, the handle can be detached from the retaining wall, and the retaining ring can be used to lift and carry the dolly-truck with its load when necessary.
In another embodiment, the dolly-truck has a ring, (called "kick ring"), which permits short distance rolling movement in the upright position by a user pushing on the kick ring with the user's foot. The kick ring frees the user's hands while the dolly-truck is propelled by foot. In one embodiment, a surface of the dolly-truck body (called "spill surface") is located between the kick ring and the retaining wall, and holds any liquid or other contents spilled out from the object during movement (in either the upright or tilted position) of the dolly-truck. The spill surface can also be used to carry tools. In another embodiment the dolly-truck has a shelf for holding additional tools that are supported by the spill surface.
In one embodiment, the dolly-truck caster wheels are shielded ball caster wheels which carry load easily on flat, smooth, and carpeted surfaces. The shielded ball caster wheels also prevent spilled liquid from being conveyed or tracked by the wheels. In this embodiment, the body of the dolly-truck is formed from one piece of molded, high-strength plastic. In two variants of this embodiment, the body is injection molded and rotational molded. Moreover, depending on the embodiment, the body is either solid or hollow. The parts of the dolly truck which hold the handle, the truck wheels and the caster wheels are also molded into the body.
To assemble one embodiment of the dolly-truck, the axle and the truck wheels are attached and the caster wheels are popped into molded holes in the bottom of the unit. The handle is placed into the extension tubes and the adjustment knobs are tightened to secure the handle to the body. In alternative embodiments, the dolly-truck is made of fiberglass, steel tubing and/or formed of aluminum, and retains one or more of the features discussed above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates one embodiment of a dolly-truck in an upright position in accordance with this invention.
FIG. 2A illustrates a bottom view of the body of the dolly-truck taken in the Y direction shown in FIG. 1.
FIG. 2B illustrates a sleeve and a corresponding caster wheel for use in the body of FIG. 2A.
FIG. 3A illustrates an isometric cross-sectional view of the body of the dolly-truck taken in the X--X direction shown in FIG. 1.
FIG. 3B illustrates, in an enlarged view, a portion of the body cross-section circled in FIG. 3A.
FIG. 3C illustrates assembly of the caster wheel of FIG. 2B into the body of FIG. 3B.
FIG. 3D illustrates a locking caster wheel for use in the body of FIG. 2A.
FIG. 3E illustrates, in a perspective view, the use of a spill surface to hold tools in the dolly-truck of FIG. 1.
FIG. 3F illustrates, in a perspective view, use of the dolly-truck of FIG. 1 as a chair by a user.
FIG. 4 illustrates one embodiment of a dolly-truck in a tilted position.
FIG. 5 illustrates a bottom view of one embodiment of a dolly-truck.
FIGS. 6A, 6B and 6C illustrate, in a perspective view, a rear elevation view, and an enlarged view respectively a dolly-truck handle brace having lid clips (FIG. 6A) for holding the lid (FIGS. 6B and 6C) of a bucket.
FIG. 6D illustrates, in an enlarged view, use of clips in an alternative embodiment for holding a bucket.
FIG. 6E illustrates, in an enlarged view, the use of the clips of FIG. 6D to hold a basket and bucket lid simultaneously.
FIG. 6F illustrates assembly of the clips of FIGS. 6D-6F and the handle to form a dolly-truck.
FIG. 6G illustrates, in an enlarged view, the insertion of an arm 48A of handle 48 into extension tube 45 during the assembly of the dolly-truck of FIG. 6F.
FIGS. 7A,7B and 7C illustrate, in perspective view, another embodiment of a dolly-truck having a retaining structure formed by an open semicircular retaining wall and an open semicircular retaining ring.
FIG. 7D illustrates the retaining knob of FIG. 7A having at one end a suction cup for holding an object in the dolly-truck.
FIG. 7E illustrates, in a perspective view, another retaining structure having a closure member for opening a retaining ring.
FIG. 7F illustrates, in an enlarged view, the push-button latch of FIG. 7E used to lock the closure member into the retaining ring.
FIG. 7G illustrates yet another retaining structure that has a hinged closure member.
FIG. 7H illustrates the retaining structure of FIG. 7G with the closure member in the closed position.
FIGS. 8A-8G illustrate a base formed by rotational molding in one embodiment of the invention.
FIGS. 9A-9E illustrate a retaining structure also formed by rotational molding for use with the base of FIGS. 8A-8G.
FIG. 10A illustrates a dolly-truck formed by attaching the retaining structure of FIGS. 9A-9E to the base of FIGS. 8A-8G.
FIG. 10B illustrates use of the dolly-truck of FIG. 10A to carry the prior art bucket and pump of FIGS. 1A-1B.
FIGs. 11A-11B illustrate a prior art bucket with a pump that can be moved by the dolly-truck of this invention.
DETAILED DESCRIPTION
FIG. 1 illustrates one embodiment of a dolly-truck 18A that includes a body 17 for supporting the object to be conveyed, such as, for example, an open bucket of liquid (shown in FIGS. 7A and 7B for another embodiment). Body 17 includes a base 12 (also called "platform" having an upper surface 12A, a lower surface 12B and a periphery 12C. In one embodiment, base 12 is a solid fiberglass disk e.g. 3/4 inch thick and 16 inches in diameter, although a base can be hollow depending on the embodiment (e.g. FIGS. 8A-8G).
On periphery 12C of base 12 are provided a number of caster wheel supports 9A, 9B and 9C. Although only three caster wheel supports 9A, 9B and 9C are visible in FIG. 1, dolly-truck 18A in this embodiment has a total of five caster wheel supports which are integrally connected to base 12 (see FIG. 2). Other numbers of caster wheel supports such as three, four, six or more are used in other embodiments.
FIG. 2A shows a bottom view of body 17 of dolly-truck 18A of FIG. 1 as seen in the Y (i.e. vertical) direction. In the embodiment shown in FIG. 2A, five caster wheel supports 9A-9E are arranged at five corner-points of a hexagon which is substantially enclosed in periphery 12C of base 12 (FIG. 1). In one specific embodiment, caster wheel supports 9A-E are metal sleeves e.g. approximately 1 inch in outer diameter, 1/4 inch in inner diameter and 12 inches in length. FIG. 2B illustrates a typical sleeve 9F which can be used as one of caster wheel supports 9A-9E (FIG. 2A).
On periphery 12C of base 12 are also provided a pair of truck wheel supports 13A and 13B integrally connected to base 12. Truck wheel supports 13A and 13B are arranged equidistant from a sixth corner-point 19 of the hexagon. In the embodiment shown in FIG. 2, body17is provided with ribs 16A-16F on lower surface 12B of base 12 to provide additional structural strength to base 12. Other structural features can also be used to provide strength to base 12. In one embodiment, no such additional features are provided in base 12 for strength.
Referring back to FIG. 1, in this particular embodiment, dolly-truck 18A has five caster wheels (such as 10A, 10B and 10C) supported by caster wheel supports (such as 9A, 9B and 9C). The five caster wheels 10A-10E are supported such that the centers of all five caster wheels 10A-10E lie in one plane (not shown explicitly). The five caster wheels 10A-10E provide dolly-truck 18A with rolling movement over short distances in an upright position.
The distance d4 between caster wheels 10A-10E from the center of base 12 is 9 inches, which is greater than the 6 inch radius of a bucket conveyed in one embodiment. Therefore periphery 12C completely encloses the area of upper surface 12A covered by the object being conveyed. Such an arrangement ensures stability of dolly-truck 18A allowing dolly-truck 18A to be propelled by foot and to be tilted easily. Also base 12 is at a distance d5 of e.g. approximately 4 inches from the ground surface 20. Base 12 being close to the ground surface 20 provides stability to dolly-truck 18A.
Caster wheels 10A-10E can be any caster wheel such as ball caster wheel 10F illustrated in FIG. 2B. In one embodiment ball caster wheels 10A-10E and sleeves 9A-9E are shielded chrome ball caster Part # CH 2051CP of Baker Sales Designers Hardware Catalog, 1993 available at any hardware store, such as Channel City Lumber, 35 Aero Camino, Goleta, Calif.
Dolly-truck 18A of FIG. 1 also has an axle11 supported by truck wheel supports 13A and 13B. Two truck wheels 14A and 14B are mounted on axle11in a casterless manner, e.g. with 3/8 inch axle cap nuts Part # 887H from Hillman Fastener Catalog 1993 available at Mission Hardware 5754 Hollister Avenue, Goleta, Calif. The two truck wheels 14A and 14B also provide dolly-track 18A with rolling movement, but in the tilted position.
Although an axle11is used in the embodiment of dolly-truck 18A illustrated in FIG. 1, truck wheels 14A and 14B can be attached to a body 17 by any other mechanism provided the truck wheels 14A and 14B are mounted parallel to each other in a non-swivelling casterless manner. In one embodiment, truck wheels 14A and 14B are 4 inch rubber wheels Part # W.S.R.40 156N3 from Baker Sales Designers Hardware Catalog, 1993.
Truck wheel supports 13A and 13B extend forward from base 12 for a distance sufficient to provide clearance between truck wheels 14A and 14B and nearby caster wheels 10A and 10B respectively. The distance between a tangent to periphery 12 and a line parallel to the tangent passing through the center of axle 11 (shown dotted in FIG. 2) is the distance d1 in FIG. 2. In one embodiment, truck wheels 14A and 14B extend distance d1 of 4 inches from the periphery of base 12.
Also, truck wheel supports 13A and 13B are positioned such that truck wheels 14A and 14B have a clearance from ground surface 20 when caster wheels 10A, 10B and 10C are in contact with ground surface 20. Clearance d2 (FIG. 1) is the distance between ground surface 20 and a plane parallel to ground surface 20 and tangential to truck wheels 14A and 14B. In one embodiment, truck wheels 14A and 14B have a diameter of 33/4 inches and are mounted on truck wheel supports 13A and 13B so as to have a clearance of d2 1/4 inch from ground surface 20. Truck wheels 14A and 14B allow dolly-truck 18A to convey an object over obstacles or negotiate stairs with tilting motion of a hand truck.
Thus, when dolly-truck 18A is moved in an upright position (see FIG. 1), dolly-truck 18A moves with caster wheels 10A-10E in contact with ground surface 20. The clearance d2 between truck wheels 14A-14B and the ground surface allows dolly-truck 18A to be moved on caster wheels 10A-10E in the upright position without any interference from the casterless truck wheels 14A and 14B.
To negotiate obstacles, dolly-truck 18A is tilted using handle 1 and moved in a tilted position, in which case the caster wheels 10A-10E are off (i.e. do not contact) ground surface 20, and truck wheels 14A and 14B are in contact with ground surface 20, similar to the tilted position of dolly-truck 18B in FIG. 4. Dolly-truck 18A can be moved easily in a tilted position on truck wheels 14A and 14B because truck wheels 14A and 14B are mounted parallel to each other in a non-swivelling casterless manner. Furthermore, truck wheels 14A and 14B can be positioned along the edge of a stair to go up or down staircases.
The small amount of clearance d2 of e.g. 1/4 inch allows dolly-truck 18A to move from the upright position into the tilted position within a small tilt angle θ (FIG. 4 ) of e.g. 10°. Such a small tilt angle allows a dolly-truck containing an open bucket with a liquid to be tilted without spilling the liquid on to ground surface 20. A larger tilt angle can be used if the center of mass of the liquid is low. Accordingly, dolly-truck 18A has the versatility to be used as a dolly for omnidirectional movement and at any time to be tilted and be used as a hand truck for negotiating obstacles.
FIG. 3A shows an isometric cross-sectional view of body 17 of dolly-truck 18A taken in the X--X direction shown in FIG. 1. Body 17 includes a retaining structure 60 formed in this embodiment by a wall (also called "retaining wall") 6, mounted in a central portion of upper surface 12A of base 12. In one embodiment, retaining wall 6 has a lower end 6L formed integral with base 12. However, retaining wall 6 can be formed as a separate piece that is attached to body 17, for example as illustrated in FIGS. 8A-8G and 9A-9E. Retaining wall 6 completely surrounds an object (e.g. a container) being transported and holds the object in its place (e.g. substantially stationary) on upper surface 12A of base 12 during movement of dolly-truck 18A (e.g. by kicking on a kick ring 8 as described below).
Therefore, retaining wall 6 of this embodiment has a height Hr that is at least sufficient to prevent the object from sliding around on base 12, and preferably sufficient to keep the object from tipping over during movement of dolls-truck 18A. Height Hr in one particular embodiment is larger than one quarter the height of the object and preferably larger than one third the height of the object. Moreover, height Hr is an order of magnitude larger than the height of a rib (e.g. one of ribs 16A-16F of FIG. 2 A). In one embodiment, height Hr is 7 inches and ribs 16A-16F have a height of 0.50 inch. In this embodiment, retaining wall 6 has a diameter Dr of 12 inches.
In this particular embodiment, retaining structure 60 has, at an upper end 6U of wall 6 (FIG. 3A), a retaining ring 3 with an optional lip 3L at the free end of ring 3. Retaining ring 3 serves to keep the top of an object e.g. a lid of bucket 42 (FIG. 3F) from moving substantially when dolly-truck 18A is moved or is tilted. Furthermore, in this embodiment, retaining wall 6 has holes 6A-6E (FIG. 1) that improve visibility of a label 55 (FIG. 3F) on bucket 42. In the embodiment of dolly-truck 18A of FIG. 3B, each caster wheel support (such as support 9C) is mounted in a slot (such as slot 15B). To assemble dolly-truck 18, axle 11 and truck wheels 14A and 14B are attached and sleeves 9A-9E are epoxied into the corresponding holes such as hole 15B of body 17 (FIG. 3C). Other methods of joining sleeves 9A-9E into their corresponding holes can also be used. Then caster wheels 10A-10E are popped into sleeves 9A-9E.
In one embodiment of this invention, instead of a ball caster wheel such as part number CH2051CP (above), dolly-truck 18A has a grip neck stem locking caster wheel (illustrated in FIG. 3D) such as part number 472-31-0012-00-00 of Plastic Guide Catalog 20-E, 1994 available from Plastic Guide-Comtek Division, 105 Progress Lane, Waterbury, Conn. 06705. Such a locking caster wheel (FIG. 3D) allows the caster wheel to be locked which in turn allows dolly-truck 18A to remain stationary on a tilted surface.
In one embodiment of dolly-truck 18, body 17 (FIG. 3A) includes a kick ring 8 mounted on a top portion of periphery 12C of base 12. Kick ring 8 allows short distance rolling of dolly-truck 18A in the upright position by a user pushing on kick ring 8 with the user's foot which frees the user's hands. In one embodiment, kick ring 8 has a cross-sectional diameter of e.g. 1 inch. Therefore, retaining wall 6 (FIG. 3A) has a height Hr that is larger than the height Hk (FIGS. 3A-3B) of kick ring 8. In one particular embodiment, retaining wall height Hr (e.g. 7 inches) is several times the kick ring height Hk (e.g. 1 inch).
In one embodiment of dolly-truck 18, a clearance is provided between kick ring 8 and retaining wall 6 to expose an annular portion of upper surface 12A of base 12. The annular portion forms a spill surface 7 that holds any contents (such as a liquid or a powdery chemical) spilled from an open bucket during any movement (in the upright or tilted position) of dolly-truck 18. In one embodiment, spill surface 7 has an annular width e.g. approximately 21/2 inch (see annular surface width "d3" in FIG. 3A) around retaining wall 6.
In this embodiment, spill surface 7 (FIG. 3E) is also used to carry tools, such as a hammer 61, a roller brush 62, a flat brush 63 and scissors 64. As illustrated in FIG. 3E, such tools lie flat (e.g. horizontal) on spill surface 7, although tools can also be supported vertically as illustrated in FIG. 7G (described below). Kick ring 8 at the periphery of spill surface 7 ensures that such tools remain on spill surface 7 during movement of dolly-truck 18A. In this embodiment, the kick ring height Hk (e.g. 1 inch; see FIGS. 3A-3B) is greater than the thickness of a tool, e.g. flat brush 63 (FIG. 3E). In another embodiment, kick ring height Hk is smaller than a tool's thickness but is greater than one half of the tool's thickness. In any event, kick ring height Hk must at least be sufficient to prevent tools from sliding off surface 7 during movement or tilting of dolly-truck 18A.
Moreover, a user 65 (FIG. 3F) can sit on a lid 37 of bucket 42 centered at the center C (FIG. 3E) of retaining structure 60. While seated, user 65 can work (e.g., paint signs) and if necessary simply bend down to place a tool in or retrieve a tool from spill surface 7. Furthermore, user 65 can move dolly-truck 18A while seated on lid 37 by simply pushing on ground surface 20 with feet 65F, similar to moving an office chair while seated.
In one embodiment of dolly-truck 18, caster wheel supports 9A, 9B and 9C are placed at the periphery of base 12, adjacent to and integrally connected with kick ring 8 (see FIG. 3B ). Such a distant placement of caster wheels 10A-10E from the center of base 12 provides greater stability to dolly-truck 18A as compared to placement of caster wheels 10A-10E closer to the center. Specifically, the peripheral placement of caster wheels 10A-10E permits propulsion by pushing on kick ring 8 with a foot.
Referring back to FIG. 1, dolly-truck 18A also includes an optional adjustable handle 1 which is connected to and extends forward and upward from body 17. Handle 1 has two arms 1A and 1B which are mounted in extension tubes 5A and 5B of retaining wall 6 and fictionally held in place in the extension tubes 5A and 5B, in this specific embodiment, by adjustment knobs 4A and 4B. Handle arms 1A and 1B are connected to each other by a handle brace 2A. The two arms of handle 1 are placed into extension tubes 5A and 5B and adjustment knobs 4A and 4B are tightened to secure handle 1 to body 17. Thus handle 1 is securely and rigidly attached to body 17 by knobs 4A and 4B so that body 17 tilts on truck wheels 14A and 14B when handle 1 is pushed downward in direction D (FIG. 4 ). The peripheral placement of caster wheels 10A-10E in supports 9A-9E (FIG. 3A) as described above allows easy tilting of body 17.
In one embodiment, handle 1 is a single tube of aluminum of 13/16 inch outer diameter, 5/8 inch inner diameter and 38 inches in length, formed into a U shape as shown in FIGS. 1 and 5. Adjustment knobs 4A and 4B can be any knobs such as rosette knob for a 1/4 inch Allen screw, Part # SPI 99-607-4 of Swiss Precision Instrument Catalog, 1993 from Specialty Tool & Bolt, 108 Aero Camino, Goleta, Calif.
Extension tubes 5A and 5B are formed as an integral part of retaining wall 6 and are supported by a solid portion 6F of wall 6. Extension tubes 5A and 5B have longitudinal holes (not shown) in the Y direction of sufficient diameter to accept arms 1A and 1B of handle 1. In one embodiment, longitudinal holes in tubes 5A and 5B have a diameter of 11/4 inch, a length of 7 inches, and longitudinal hole of diameter 3/4 inch and 61/2 inches depth. Also, extension tubes 5A and 5B have lateral holes (not shown) which are threaded to accept screws extending from adjustment knobs 4A and 4B. Handle 1 can be raised or lowered with respect to tubes 5A-5B, depending on the height of the user. Adjustment knobs 4A and 4B can be unscrewed to allow handle 1 to be moved up and/or down to adjust the position of handle 1. The position of handle 1 can be adjusted by an amount equal to the length of extension tubes 5A and 5B.
Handle 1 is used by a user to move dolly-truck 18A in a rolling movement in an upright position (FIG. 1A) similar to a conventional dolly and also to move dolly-truck 18A in a tilted position over obstacles (FIG. 4A) similar to a conventional hand truck. If handle 1 interferes with any given process or use of the dolly-truck, handle 1 can be completely removed from extension tubes 5A and 5B of retaining wall 6. Then retaining ring 3 is used to lift and carry dolly-truck 18A (and the bucket) when necessary. Such a configuration is especially advantageous for short distance movement activities such as painting, because body 17 of the dolly-truck 18A can be pushed by foot.
FIG. 4 shows an alternative embodiment of a dolly-truck 18B in accordance with this invention. Dolly-truck 18B has the same features as those discussed above for dolly-truck 18A of FIG. 1 (except for caster wheel supports, caster wheels and handle brace). Many of the same reference numerals are used in FIGS. 1 and 4 for convenience.
Caster wheel supports 20A-20E of dolly-truck 18B are arranged equidistant from each other at the five corners of a pentagon as shown in a bottom view in FIG. 5. Two caster wheel supports 20A and 20B are arranged adjacent truck wheel supports 21A and 21B. Caster wheels 22A-22E which are supported by caster wheel supports 20A-20E are shielded ball caster wheels. The shields on the balls prevent spilled liquid from being conveyed or tracked by wheels 22A-22E.
Also in the embodiment of FIG. 4, retaining ring 3 has retaining knobs 3A-3D (similar to adjustment knobs 4A and 4B ) with screws which secure the object being carried firmly to dolly-truck 18B. Dolly-truck 18B also has a handle brace 2B which is different from handle brace 2A of dolly-truck 18A. Handle brace 2B has a surface contoured (as described below in reference to FIG. 6A) to allow stacking of a number of buckets, one on top of another and moved by dolly-truck 18B in the tilted position illustrated in FIG. 4. Handle brace 2B is supported by handle 1 at a distance from base 12 sufficient for handle 1 to support one or more objects staked on top of one another.
In one embodiment, body 17 of dolly-truck 18A is formed as a single piece of fiber-glass and in alternative embodiments body 17 is formed of polyethylene or other polymeric material, of metals such as steel and/or aluminum or other material. Holes (such as holes1 5A and 15B) are either molded into body 17 as body 17 is being formed or drilled into body 17 after body 17 has been formed.
In one embodiment, body 17 of dolly-truck 18A is formed as one piece of injection molded, high-strength plastic. Extension tubes 5A and 5B, truck wheel supports 13A and 13B, caster wheel supports 9A, 9B, 9C, 9D and 9E, retaining wall 6, retaining ring 3, kick ring 8, base 12 and ribs 16A-16E and 16F are all molded into body 17.
FIG. 6A illustrates a handle brace 30 similar to braces 2A and 2B (FIGS. 1 and 4) of respective dolly-trucks 18A and 18B. Handle brace 30 has a brace body 31 which has an inner surface 31A contoured to allow stacking of a number of buckets one on top of another. In one embodiment, surface 31A has a concave cylindrical curvature with a radius of 6 inches. Handle brace 30 also includes arm sleeves 35A and 35B on outer surface 31B of brace body 31. Arm sleeves 35A and 35B are similar to extension tubes 5A and 5B (above) and have an outer diameter of e.g. 11/4 inch and an inner diameter of 3/4 inch. Handle brace 30 has a height H e.g. 21/2 inches.
Also included in handle brace 30 are lid clips 32A and 32B. Lid clips 32A and 32B preferably of a somewhat elastic material capable of being bent out of position and then snapping back into position, are supported at one end by arm sleeves 35A and 35B respectively. At the other end, lid clips 32A and 32B are provided with finger grips 33A and 33B respectively. Lid clips 32A and 32B are formed in the shape of an L with the shorter leg having a length S1 e.g. 3/8 ths inch and the longer leg having a length S2 e.g. 1/2 inch.
Lid clips 32A and 32B are used to hold a lid 37 of e.g. a five gallon bucket 42 in a dolly truck 40 as shown in FIG. 6B. The arms of handle 41 are passed through arm sleeves 35A and 35B of handle brace 30. A lid 37 is supported by lid clips 32A and 32B by pulling finger grips 33A and 33B outward and sliding lid 37 in the space between lid clip 32A and 32B and arm sleeve 35A and 35B respectively (FIG. 6C), and releasing finger grips 33A and 33B.
Instead of "L" shaped clips 33A-33B (FIGS. 6A-6C), other types of clips can also be used in a dolly-truck. For example, clips 38-39 (FIGS. 6D-6F) have the shape of the letter "S". Specifically, clips 38-39 have upper portions 38U-39U respectively in the shape of the letter "J", and are connected to a brace 40 (at the respective short ends of the "J" portion) by respective bolts 41-42 (FIG. 6F). Upper portions 38U-39U allow clips 38-39 to hold a lid 37 (with the respective stems of the "J" portion) in the manner described above.
Clips 38-39 also have lower portions 38L-39L respectively that also have the shape of the letter "J" and are used as hooks to hold objects, such as a handle of a container, such as bucket 43 (FIG. 6D) or a basket 44 (FIG. 6E). Bucket 43 can be used to hold a powdery chemical or a liquid for use with tools 61-64 (FIG. 3E). Alternatively, basket 44 can be used to hold additional such tools. Therefore, the same clips 38-39 are used to simultaneously hold two different items: a lid 37 and a basket 44 (FIG. 6E). Such dual use eliminates the need for an additional set of clips (one set for each use) and so reduces cost.
Note that in this embodiment, height Hr (FIG. 6B) of the retaining structure 60 is at least one quarter as large as height Ho of bucket 42. Height Hr is preferably at least one-third of height Ho, and ensures that retaining structure 60 holds bucket 42 during movement of the dolly-truck.
In the embodiment illustrated in FIG. 6F, body 17A is substantially identical to body 17 discussed above except that body 17A includes brace 40 and tubes 45 and 46. Tubes 45-46 are secured by knobs 4A-4B into extension tubes 5A-5B as described above, although in an alternate embodiment tubes 45-46 can be epoxied (i.e. permanently mounted) in tubes 5A-5B. Tubes 45-46 support brace 40 which in turn has arm sleeves 47A-47B to receive handle 48. In this particular embodiment, the same screws 41-42 that are used to secure clips 38-39 to brace 40 are also used to secure handle 48 in tubes 47A-47B. In one variant of this embodiment, arm sleeves 47A-47B are formed by tubes 45-46 (FIG. 6G), although in another embodiment, tubes 47A-47B are formed as holes molded into brace 40.
In body 17A (FIG. 6F), handle 48 can be replaced by handles of other shapes and configurations that may be required for different purposes. In one embodiment, arm sleeves 47A-47B are formed as portions of tubes 45-46, and the position of handle 48 with respect to retaining structure 60 can be adjusted by a distance at least equal to the length of tubes 45-46 by sliding the arms 48-48B into (and out of) tubes 45-46. The position of handle 48 can be further adjusted an additional length of extension tubes 5A-5B by sliding the tubes 45-46 into (and out of) extension tubes 5A-5B.
FIGS. 7A-7C illustrate another embodiment of a dolly truck 50 having a retaining wall 51 and a retaining ring 52 which are open in region 56, and in all other respects dolly truck 50 has the same components as dolly truck 18A of FIG. 1. The open arrangement of dolly-truck 50's retaining wall and retaining ring FIG. 7A permits bucket 42 to be placed in the center on upper surface 54A of base 54 without bucket 42 having to be lifted over the retaining ring (which is necessary for dolly-truck 18A of FIG. 1). In the specific embodiment shown in FIGS. 7A-7C, retaining wall 51 and retaining ring 52 are semi-circular in shape, although any other open shape can be used in other embodiments. Bucket 42 is securely held in place on base 54 by retaining knobs 53A and 53B (similar to retaining knobs 3A-3D of FIG. 4 above).
In one particular embodiment, each of knobs 53A-53B has a holding device, e.g. a suction cup 55A attached at one end of knob 53A (FIG. 7D). Suction cup 55A (or any other such holding device) is pushed against a cylindrical surface of bucket 42 when the adjustment knob 53A is screwed in, and thereby holds bucket 42 in place during movement of dolly-truck 50.
In another embodiment, dolly-truck 50 includes a closure member 57 that closes the opening in region 56 (FIG. 7E). In this particular embodiment, retaining ring 56 is hollow, and closure member 57 slides into a space 52S enclosed by retaining ring 52. Closure member 57 includes a latch 57L (e.g. a spring loaded button) which locks into another hole 52L in retaining ring 52 for closing the opening 56 during operation of dolly-truck 50. To form opening 56, the user merely pushes on latch 57L with one hand while pulling a peg 57P (formed on closure member 57) in a direction away from hole 52L (see direction Z in FIG. 7E), thereby to slide closure member 57 into retaining ring 52.
In another embodiment, closure member 58 (FIG. 7G) is mounted by a hinge 58H to retaining wall 51, thereby to allow closure member 58 to pivot while forming the opening 56. Closure member 58 also includes a latch 58L for securing the free end 58F to retaining ring 52 as illustrated in FIG. 7H. Latch 58L can also be a spring loaded button that can be pulled up from a hole 51H in wall 51, thereby to allow pivoting of closure member 58 about retaining wall 51.
In this particular embodiment, dolly-truck 50 also includes a shelf 59 mounted on retaining ring 52 adjacent to but above truck wheels 61A-61B in a plane parallel to surface 54S. Shelf 59 has a number of holes, e.g. hole 59H that can be used to hold tools. For example, a handle 61H of hammer 61 is inserted through hole 59H so that handle 61H is supported on spill surface 54S. Although not illustrated in FIG. 7G, spill surface 54S can have an indentation located opposite to hole 59H of shelf 59 to receive handle 61H, thereby to keep hammer handle 61H substantially parallel to retaining wall 51.
Any number of such devices for holding and supporting tools can be physically attached to any portion of dolly-truck 50. For example, dolly-truck 50 also includes, mounted on handle 61, a clip 60 that holds a pole 62 passing through another hole (not labelled) in shelf 59 and supported on spill surface 54S (pole 62 is also held parallel to retaining wall 51). Moreover, although not illustrated in FIG. 7G, pole 62 can be supported on spill surface 54S even in a dolly-truck devoid of shelf 59, because pole 62 is held by clip 60.
In another embodiment, a dolly-truck 100 (FIG. 10A) includes a base 80 (FIGS. 8A-8G) formed separate and distinct from retaining structure 90 (FIGS. 9A-9E). Retaining structure 90 is attached to base 80, for example, by fasteners (not shown in FIGS. 8A-8G, 9A-9E and 10A-10B), such as screws or bolts. Base 80 is similar to the above-described base 12 (FIG. 1) and base 54 (FIG. 7 A) except for the following differences. Base 80 (FIG. 8A) has a substantially annular shape with an opening 80H in the center C. Opening 80H of a size sufficient to allow a hand, a hose or cleaning equipment to be moved easily through the opening, allows dolly-truck 100 to be cleaned more easily than dolly-truck 18A (FIG. 1). Hole or opening 80H also results in dolly-truck 100 requiring less material and having lower weight and cost as compared to dolly-truck 18A.
In the embodiment illustrated in FIGS. 8A-8G, hole 80H is keyed by recesses 81A-81D formed symmetric with respect to each other around and as part of an inner periphery 80I of base 80. Recesses 81A-81D accommodate tabs (described below) of retaining structure 90 (FIG. 9A) when retaining structure 90 is attached to base 80. Retaining structure 90 is used to hold, for example, a 5 gallon bucket. Moreover, base 80 (FIG. 8A) has depressions 82A-82D (e.g. 1/4 inch deep) formed in an upper surface 80U of base 80. Depressions 82A-82D accommodate protrusions (described below) of retaining structure 90 (FIG. 9A). Specifically, in this embodiment, outer periphery 80P of depressions 82A-82D matches the footprint of retaining structure 90 (FIG. 9C). Such matching of footprint maximizes contact between the surfaces of structure 90 and base 80, thereby spreading the weight of an object carried by structure 90 over a larger surface of base 80 (as compared to a structure with a footprint unmatched by the base). Moreover, base 80 has a number of holes 83A-83D (FIG. 8A) that match the respective holes (also described below) of retaining structure 90. Holes 83A-83D are used to hold fasteners that attach retaining structure 90 to base 80.
Base 80 also has a peripheral wall 84 similar to the above-described kick ring 8 (FIG. 1) except that wall 84 is not circular in shape (and also not circular in cross-section). Instead, peripheral wall 84 has a number of vertices, including four vertices 85A-85D (FIG. 8A) that are located at the four corners of a square 85. Vertices 85A-85D are located along the diagonals (not labeled) of square 85, thereby to permit placement of caster wheel supports (e.g. depressions 86A-86B of FIG. 8D) at a larger radial distance from center C, as compared to, for example, the circular periphery of kick ring 8 (FIG. 1). Specifically, use of four vertices 85-85D (FIG. 8A) of square 85 for placement of the caster wheel supports provides greater stability than the use of a circle with a radius same as the lateral distance D191 (FIG. 8A) of wall portions 84A-84C from center C.
Wall portions 84A-84C (FIG. 8A) are portions of peripheral wall 84 that are convex (e.g. arcs of a circle) and that connect four vertices 85-85B of square 85 on three sides of square 85. On the fourth side of square 85, peripheral wall 84 includes a fourth portion 84D formed in the shape of letter "U". Portion 84D connects vertices 85A and 85B, and encloses a rectangular portion 80R (FIG. 8A) of upper surface 80U thereby to provide support for a number of tools held in holes of a shelf (e.g. shelf 59 of FIG. 7G). In this particular embodiment, the width of portion 84D is larger (e.g. 50% larger) than the width of portions 84A-84C (FIG. 8B), thereby to ensure that such tools remain within rectangular region 80R. The larger width accommodates an area needed to support tools vertically (illustrated in FIG. 7G) as well as horizontally (illustrated in FIG. 3E).
In this particular embodiment, body 80 has four caster wheel supports formed by depressions 86A-86D (FIG. 8D) located adjacent to vertices 85-85D on the lower surface 80L. FIG. 8D illustrates only half of base 80 because base 80 is symmetric about center line CL. In this particular embodiment, caster wheel supports 86A-86D are formed as rectangular depressions (e.g. 1/4 inch deep) to accommodate four FAULTLESS™ casters, part number EP4520, available in any hardware store. Although rectangular depressions are illustrated in FIG. 8D, other types of caster wheel supports, such as hole 15B (FIG. 3C) can also be used in other embodiments.
Note that in this particular embodiment, dolly-truck 100 requires only four caster wheels (not labelled; only three shown in FIGS. 10A-10B), one less than dolly-truck 18A (FIG. 1), thereby reducing cost. The four caster wheels provide adequate support because bucket 42 (FIG. 10B) is located in the center C (FIG. 9A) of retaining structure 90. Therefore, bucket 42's weight is concentrated on an annular lip 93 (as described below) that is surrounded by the four caster wheels (FIG. 10A).
Body 80 also includes two truck wheel supports 87A-87B (FIG. 8B) that are formed (e.g. as tabs) on lower surface 80L of base 80, underneath rectangular region 80R on upper surface 80U. Truck wheel supports 87A-87B have the respective axle holes 88A-88B formed at a distance D101 (FIG. 8E) from lower surface 80L. In this particular embodiment, truck wheels (not shown in FIG. 8E) have a diameter of 4 inches. Distance D101 is selected so that the height of truck wheels (e.g. 3 inches due to 1.25 inch wheel well 87D in lower surface 80L) is smaller than the height of caster wheels (e.g. 31/4 inches). Therefore in this embodiment, there is a clearance d2 (FIG. 10A; e.g. 0.25 inch), between the truck wheel (not labelled) and the ground surface 20.
In one particular embodiment, base 80 is substantially hollow (see FIGS. 8C and 8F) and is formed by rotational molding. In rotational molding, a molding material (e.g. polyethylene) is poured into a mold that is closed and rotated about two axes (a major axis and a minor axis) inside an oven for a predetermined period of time, and thereafter cooled and the mold is opened to take out the molded part. Rotational molding typically results in a hollow part, also called "double walled part" because of two walls, e.g. two portions 80A and 80B (FIG. 8C) of wall 80W. In this particular embodiment, wall 80W is formed of a plastic, e.g. cross-linked polyethylene. In another embodiment, other plastics such as high-density polyethylene and low-density polyethylene are used.
In one particular variant of this embodiment, wall 80W (FIG. 8F) has a thickness T in the range of 0.125-0.150 inch, depending on various parameters of the molding process. In this variant, each of holes 83A-83D (e.g. hole 83B in FIG. 8F) has a diameter of 0.31 inch, with a counter sunk region of diameter 0.75 inch used for a fastener, such as a 1/4-20 bolt. Note that base 80 in this embodiment includes, around each of holes 83A-83D (FIG. 8A), a region that is not hollow, but is formed by two portions of wall 80W coming together, and is called a "kiss-off". "Kiss-offs" are well known in the art of rotational molding. The "kiss-offs" of wall 80W (FIG. 8C) transfer the weight of base 80 to the respective fasteners (described below), for example when retaining structure 90 is used to lift dolly-truck 100 (FIG. 10A).
In one specific embodiment, base 80 includes four metal inserts for each caster wheel support, e.g. inserts 86B-86B4 for caster wheel support 86B (FIG. 8D) that are inserted into the mold prior to fabrication of base 80, and thereby become an integral part of base 80. The four metal inserts are used to mount a caster wheel having a plate with screws or bolts, for example, a bolt 1/4 inch in diameter with 20 threads per inch. Instead of the four metal inserts, a metal sleeve (described above) can also be used to mount a caster wheel.
Retaining structure 90 (FIGS. 9A-9E) includes a retaining wal 91 and a retaining ring 92 similar to the above-described retaining wall 6 and retaining ring 3 (FIG. 1). In addition, retaining structure 90 includes an annular lip 93 (FIG. 9A) formed integral with retaining wall 91 and located opposite to retaining ring 92. Lip 93 is formed on an inner side of retaining walls so that retaining structure 90 has, in center C, an opening 90H defined by annular lip 93. Opening 90H has a predetermined diameter D189 (FIG. 9A) that is selected to be smaller than the diameter of an object to be carried in dolly-truck 100, so that lip 93 supports the bottom surface of the object at a periphery of the bottom surface. In one particular embodiment, the distance D189 is 9 inches, and annular lip 93 supports a bucket 42 (FIG. 10B) having a diameter of 101/4 inch, such as a five gallon bucket.
In this particular embodiment, a two-part mold (not shown) is used to form retaining structure 90 by rotational molding in a manner similar to that described above for base 80. In this embodiment, retaining wall 91 has a draft angle D177 (FIG. 9E) that allows the mold parts to be easily pulled out after formation of retaining structure 90. Retaining wall 91 also has a thickness T (FIG. 9E) in the range of 0.125-0.150 inch in this embodiment. Use of rotational molding for base 80 and structure 90 results in both these parts being hollow which reduces the cost and the weight of dolly-truck 100, as compared to the weight of dolly-truck 18A (FIG. 1).
Retaining structure 90 also includes a number of tabs 94A-94D (FIGS. 9B-9D) that lock into the respective recesses 81A-81D (described above). The interlocking recesses 81A-81D and tabs 94A-94D ensure that retaining structure 90 is located coaxial with base 80, i.e. centers C (FIGS. 8A and 9A; same reference numeral "C" is used for convenience coincide. Retaining structure 90 also includes a number of protrusions 95A-95D (FIG. 9C) that fit in the respective depressions 82A-82D (also described above). The interlocking protrusions 95A-95D and depressions 82A-82D ensure that retaining structure 90 is located in the same position with respect to base 80 each time dolly-truck 100 (FIG. 10A) is assembled. Finally, in this particular embodiment retaining structure 90 also includes metal inserts 90A-90D (FIG. 9C) at locations corresponding to the locations of holes 83A-83D (FIG. 8A). Inserts 90A-90D are used for holding fasteners used to attach retaining structure 90 to base 80.
In this particular embodiment, instead of adjustment knobs 4A-4B (FIG. 1) for holding handle 1, each of extension tubes 96A-96B (FIG. 9A) formed in rear portion 90R (FIG. 9A) of retaining structure 90 has a periphery that can be adjusted by adjusting the width of respective slots 97A-97B, e.g. by tightening screws in respective holes 98A-98B. Holes 98A-98B are formed e.g. by molding with a push pin and a hole 98C (FIG. 9A) is formed by drilling rear portion 90R between extension tubes 96A-96B in a direction perpendicular to slots 97A-97B.
In one particular embodiment, a carriage bolt (not shown in FIG. 9A) passes all the way through holes 98A-98C, with a head at one end (e.g. adjacent to hole 98A). Tightening a wing nut 101 (FIG. 10A) at the other end (e.g. adjacent to hole 98B ) makes extension tubes 96A-96B smaller, resulting in frictionally holding arms 1A-1B of an inserted handle 1. Note that slots 97A-97B (FIG. 9A) of this embodiment also allow retaining structure 90 to be separated from a mold part, as would be obvious to a person skilled in rotational molding.
Moreover, in the embodiment illustrated in FIGS. 9A-9E, retaining wall 91 has a varying height, with an upper end 91U (FIG. 9D) being located in a plane P1 (shown as a line in FIG. 9D) inclined with respect to another plane P2 passing through the lower end 91L. Specifically, retaining wall 91 has a rear portion 90R having the largest height (D174-D169) adjacent to extension tubes 96A-96B, and another portion (called "front portion") 90F located diametrically opposite to rear portion 90R and having the smallest height D168.
In this particular embodiment, retaining wall 91 and retaining ring 92 have a slot 90S (FIG. 9B) in front portion 90F. Slot 90S has a width just sufficient to allow passage of a pump 110 (FIGS. 11A-11B) during placement of bucket 42 into retaining structure 90. Prior art pump 110 typically includes a cylinder 111 supported by a leg 112 that is separated by a small clearance (e.g. 1/2 inch; see FIG. 10B) in which is located the wall of bucket 42 when cylinder 111 is placed inside bucket 42.
Slot 90S (FIG. 9B) allows bucket 42 with pump 110 installed thereon to be centered at center C (FIG. 9A) of retaining structure 90 with leg 112 (FIG. 10B) extending out through slot 90S such that a foot 112F rests spill surface 80S (FIG. 8A) adjacent to slot 90S. The width D190 (FIG. 9B) of slot 90S is made barely larger (e.g. 1/2 inch larger) than the width of leg 102 so that retaining wall 91 and retaining ring 92 substantially encircle (except for slot 90S) bucket 42 (FIG. 10B). In one particular embodiment, leg 102 has a width of 4 inches, and D190 is 4.5 inches. Such encircling is sufficient to retain bucket 42 in retaining structure 90 during movement of dolly-truck 100 (FIG. 10B) and eliminates the need for retaining knobs 3A-3D (FIG. 4), thereby reducing cost. That is, in this particular embodiment, retaining wall 91 and retaining ring 92 (FIG. 10B) are devoid of any holding devices for securing an object in dolly-truck 100. Note that dolly-truck 100 formed by attaching retaining structure 90 to base 80 can be used in two different industries, the drywall industry that requires slot 90S (FIG. 9B) for accommodating pump 110, as well as the paint industry that does not require slot 90S (which can therefore be left unused).
A dolly-truck as described herein can be (1) scooted along in the upright position by pushing with one's foot on a dolly-truck kick ring or peripheral wall, (2) pushed forward by use of a dolly-truck's handle, or (3) dragged with a paint extension pole (used for rolling wall surfaces) inside an open bucket carried by the dolly-truck.
In one particular embodiment, the dimensions of the dolly-truck of FIGS. 8A-8G and 9A-9E are listed in the Table below.
______________________________________Reference Dimension in InchesNumeral (or Angle in °)______________________________________D100 1.25D101 1.0D103 15.5D104 9.0D105 3.25D106 20.5D107 3.0D108 4.5D109 5.25D110 5.75D111 7.0D112 14.0D113 0.75D114 1.0D115 0.25D116 4.5D117 19.0D118 15.5D119 1.75D120 2.5D121 3.75D122 0.25D123 0.5D124 5.25D125 4.5D126 6.13D127 3.25D128 1.75D129 2.62D130 9.5D131 6.75D132 4.25D133 4.75D134 2.5D135 1.25D136 0.25D137 1.0D138 0.25D139 3.75D140 3.0D141 0.75D142 0.25D143 1.5D144 2.5D145 1.0D146 1.0D147 5.75D148 1.0D149 0.75D150 4.5A1 30°A2 50°A3 40°A4 40°A5 10°A6 45°A7 45°D151 9.0D152 7.0D153 1.0D154 6.75D155 1.0D156 0.25D157 0.5D158 0.81D159 0.37D160 0.25D161 7.0D162 7.25D163 12.5D164 0.75D165 0.75D167 8.0D168 3.0D169 0.75D170 1.0D171 1.0D174 11.75D175 1.5D176 0.5D177 0.25D178 0.25D179 1.5D180 0.75D181 0.75D182 0.75D183 1.75D184 5.25D185 4.5D186 5.25D187 6.0D188 4.5D189 9D190 4.5A8 10°A9 20°A10 20°A11 45°A12 30°A13 30°A14 30°A15 41.5°A16 13.5°______________________________________
Although the present invention has been described in connection with the above described illustrative embodiments, the present invention is not limited thereto. For example, retaining wall 6 (FIG. 1A) can be formed as a solid surface without holes 6A-6E. Moreover, instead of five (or four) caster wheels and two truck wheels, any number of caster wheels and truck wheels can be used in accordance with this invention. Furthermore, although handle 1 (FIG. 1A) is described as being connected to body 17 in extension tubes 5A and 5B, a handle can be connected to a body in any conventional manner. Also, in an alternative embodiment, only base 80 (FIG. 10A) is solid and structure 90 is hollow thereby to ensure a low center of gravity for the resulting dolly-truck. In still another embodiment, only base 80 is hollow and structure 90 is solid. Although in the above-described embodiments, two clips have been illustrated, a single clip can be used in other embodiments of the dolly-truck. Such a single clip can be formed, for example, by welding together two or more clips 38-39 (FIG. 6D), thereby reducing the number of parts required to form the dolly-truck. Persons skilled in the art can use the above discussed embodiments as a basis for the necessary elements to be cohesively implemented to provide a durable, washable and stable embodiment of a dolly-truck. Therefore, various modifications and adaptations of the above discussed embodiments are encompassed by this invention as set forth in the appended claims.
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A multi-purpose, movable apparatus (henceforth dolly-truck) for conveying objects, such as, for example, a five-gallon cylindrical industrial bucket is described. The dolly-truck includes a one-piece, molded plastic base having caster wheels and truck wheels. The caster wheels are mounted on a lower surface of the base and provide short distance rolling movement capability in the upright position. Connected to the base are two truck support arms which support an axle with two truck wheels. The truck wheels provide a hand truck capability for negotiating stairs, bypassing obstacles and an omnidirectional capability in conveyance of objects. Centered on the base is a retaining wall for receiving and holding objects. Connected to, and integrated into the retaining wall is an adjustable handle for conveying the dolly-truck by hand. The handle can be used to move the dolly-truck on the caster wheels as a conventional dolly, or alternatively on the truck wheels as a conventional hand truck. The base of the dolly-truck is surrounded by an optional ring which allows the dolly-truck to be conveyed by foot. An annular surface of the base outside the retaining wall and inside the ring forms a spill surface that prevents spillage of liquid from an open bucket onto the floor.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for the automatic or semiautomatic control of track-guided toys, in particular electric models of railways and trains, that is realistic and true to the original, as well as to an arrangement for implementing such a method. The invention further proposes tracks, pieces of track or switches for use with an automatic method of controlling model railways and trains, as well as rolling stock, in paticular locomotives, for the same purpose. In addition, the invention relates to a method of controlling a toy with at least one toy vehicle that can be caused to travel along a roadway while being guided by tracks, as well as a method of determining the position of a toy vehicle and/or of obtaining a representation of the course of a roadway with at least one toy vehicle that can be caused to travel along a roadway while being guided by tracks. The invention also proposes arrangements for the realistic automatic or semiautomatic control of track-guided toy vehicles and roadway components for track-guided toy vehicles as well as toy vehicles that can be used for the purpose.
2. Discussion of the Background
Digital model-railway control systems have been state-of-the-art for several years. In such control systems the full driving voltage, e.g. 16 V, is continually applied to the track. The rails serve simultaneously to transmit digital data, forming a so-called data bus.
For this purpose, appropriate digital control commands are superimposed on the driving voltage. These digital control commands are encoded by a control system in a digital transmission format, e.g. NMRA/DCC, and are decoded in the particular model. For this decoding each locomotive comprises a so-called “locdecoder”, which sends out signals specifying direction, velocity and ancillary functions, such as activation of lights or automatic coupling, that correspond to the user's commands. Such decoders can also be used in other functional articles such as cranes, switches or the like, for the remote triggering of control commands.
The advantage of digital systems resides in the fact that all control commands can be transmitted through the track. Accordingly, the entire installation, with locomotives, functional models and switches, can be operated by way of a double-pole connecting cable. The elaborate cable arrangements that are a conventional part of the analog technology are eliminated.
Because the individual decoders can be targeted by way of a freely programmable address, several locomotives can be driven and also arbitrarily turned off entirely independently of one another, on a single circuit. Track-separation sites are no longer needed.
Hence the digital technology presented here offers substantial advantages both in setting up the installation and also while playing, but as yet there are no systems adequate to meet practical demands and economical in construction that would make possible detection of the position of the rolling stock, i.e. the trains, on the roadway. However, it is only when the exact positions of the vehicles and their current velocities are known that an action control is possible, e.g. sending out specific stop commands, maintaining predetermined velocities, specification of particular routes and so on. Ultimately, above all in the case of large installations, monitoring of the train operation with detection or assignment of actual positions is extremely important, so that functional impairments can be identified and possible collisions avoided during operation of the model railway.
SUMMARY OF THE INVENTION
It follows from the preceding that the objective of the invention is to disclose a method and an arrangement for the automatic or semiautomatic control of track-guided toys, in particular electrically powered model railways and trains, that are as realistic and true to the original as possible, that provide economical means of allowing the position of the rolling stock to be detected exactly, and that make it possible for a representation of the route or track to be recorded by simple means while the route itself is being travelled, as well as to transmit these data to a central memory for the execution of control and monitoring tasks, so that once an installation has been set up, elaborate manual route monitoring is eliminated.
Another aspect of the invention is that a track, track piece, switch or the like is disclosed for use with the cited method, as well as suitable rolling stock.
The objective of the invention is achieved with respect to the method by the teaching according to Claim 1 , and with respect to the arrangement by the means given in Claim 10 .
With respect to the tracks, track pieces, switches or the like that are suitable for use with the method in accordance with the invention, reference is made to Claim 11 , and with respect to the rolling stock, to Claim 15 .
The subordinate claims comprise at least advantageous embodiments and further developments of the invention.
The basic idea underlying the invention, as set forth in the claims, resides in achieving a detection and feedback of the momentary position of the rolling stock on route so that by way of the feedback possibility thus provided, a realistic running operation is possible, such that in addition to the position the absolute model velocity is also determined, which enables a number of features: for example, precise stopping in front of signals as well as control of velocity limits by way of signals or prescribed by a central controller, the actions of stationary trains in front of signals, such as emitting indicator lights and sounds, and also waiting times at the cleared exit signal.
Running operation designed in this way, such that the exact position is monitored with precision in the decimeter range, also prevents encounters involving flanking, intersecting or frontal travel, with correspondingly high safety during play.
As a result of the teaching in accordance with the invention, the advantages of an existing digital control system can be raised to a substantially higher utilization level; examples include the programming of individual and place-related sojourn times, an automatic digital block-signal-post operation, the positioning of three-dimensional images of the locomotive and the train on a display, in the sense of a virtual model railway, and other facilities.
In one conceivable embodiment of the invention the controlling software can be transmitted by way of a public network, e.g. the internet, so as to enable even quasi remote-controlled playing by several users, who are seated at widely separated sites and observe the progress of the game, e.g., by a webcam.
Because the method in accordance with the invention together with the associated arrangement provides an exact representation of the track, including e.g. the position of buffers, and positions can be determined with the required precision, a shunting operation in which trains are arranged in a particular sequence can be implemented, just as a locomotive can be caused to stop exactly when desired, e.g. before striking a buffer.
The positions of the vehicles, i.e. of the rolling stock, and their functional states can be detected and represented on an operator's display, which can be designed, e.g., as a touch screen.
With respect to increasing operating safety, moreover, it is possible in case of critical functional states to display warning messages that include positional information, so that the user and operator of the installation can react immediately and intervene appropriately. With reference to a record of time and place, an associated control program can be used to undertake a stepwise reduction or adjustment of the train velocity in sections where braking or velocity limitation is followed by acceleration, in the sense of intelligent braking or intelligent train operation, respectively.
Playing with the installation is also made very interesting when the user is given a means to impose temporary speed limits at construction sites along the route, or also to prescribe maximal speeds for each train, for instance to distinguish freight train, passenger train, express train etc. An especially interesting aspect is the possibility of digitally controlled parallel exits for multiple trains, with suitably adjusted velocity.
The monitoring of time and position thus enables a real train operation according to a schedule appropriate for a model railway.
In accordance with the invention each track, piece of track or switch, as well as selected buildings and other installation components, is connected to a memory unit with non-contact readout, in particular a transponder. In this memory unit or transponder are stored data specifying type and/or geometry as well as an identification code that uniquely specifies each track.
The rolling stock is equipped with a memory-reading device as well as a data-transmission means for revertive communication of the items of information that have been read out and, where necessary, decoded.
The memory-reading device is capable of receiving the data from the identification element, e.g. the transponder, by non-contact means. The transponder preferably employed is a microelectronic circuit with a transmitting and receiving antenna, control logic and storage for data and energy. This transponder can be incorporated as a complete unit, by injection, e.g., into the track ballast or a holding device or connection to the associated track or piece of track elsewhere, during the manufacturing process.
It is in accordance with the invention for the manufacturer to employ permanently programmed transponders, but the possibility also exists to use transponders that allow the stored information to be overwritten by means of a special programming device.
The transponders preferably derive the energy needed for the transmission of information from the electromagnetic field created when the memory-reading device is connected to or brought into the vicinity of the transponder. In this situation the writing/reading antenna of the memory-reading device has come within the range of the transponder, so that the first event is charging of the available energy storage means, e.g. a capacitor. Then the transponder transmits the contents of a data memory, i.e. the type- and/or geometry-specifying information regarding the particular track, including the individual identification code, to the memory-reading device. The dialog or data transmission is repeated cyclically as long as the transponder and memory-reading device are within transmission range of one another; in this process data security during transmission is ensured by a prescribed data protocol.
After an installation comprising the special tracks, track pieces and/or switches, as well as the memory components with non-contact readability, has been completed or appropriately reconfigured, the entire route is travelled for the first time with rolling stock of the kind described above, i.e. having at least one memory-reading device. During this initial circuit the track configuration is “scanned” and the result is entered into a superordinate control system by way of the data-transmission means. This is made possible by the individual identification (length and type of track) and the specified geometry of each track or piece of track. In this way the control system and the control software it contains receive an exact electronic representation of the installation with all its elements—including, e.g., signals, switches and buffers, which can also be equipped with transponders. That is, the electronic system would be capable of operating the trains on its own.
In the case of relatively large installations with extremely high requirements for precision and/or resolution, it is further possible to provide a specific, geometrically exactly determined reference point, which can be used for initial measurements so that during subsequent operation the position obtained by computer calculation from the individual measurements can be calibrated when transiting or approaching the reference point.
A supplementary sensor, e.g. a magnetic-field sensor, which can be integrated into the rolling stock, makes it possible to measure directional changes, in particular during the initial traveling and scanning-in of the route and generation of the track image, so that the route can be recorded in a shorter time and with less elaborate calculation.
A similar supplementary sensor system is able to detect changes in the vertical orientation of the route, e.g. downward or upward gradients, so as to have command over installations constructed in more than one plane. For example, it is useful here to have an electronic slope sensor which, at prespecifiable time intervals or when specific thresholds are passed, causes direction-change information to be sent by way of the data-transmission means in the track-bound drivable machine, i.e. the locomotive.
In one embodiment of the invention memory-reading devices and data-transmission means are provided not only in the drivable machines, i.e. the locomotives, but also in the attached carriages, so that an automatic shunting is possible, e.g. to assemble trains comprising tank cars, flat cars and so on.
The data transmission, i.e. the revertive communication, can be accomplished either by way of the two-wire bus, e.g. in NMRA-DCC format, or by wireless means; it is important here to ensure real-time capability while taking into account the actual model-railway velocities.
In accordance with the method it is then possible, by means of the system controller with the use of a personal computer and its control software, to assign to selected tracks, signals, switches and/or route sections special functions, so that the operation of the system closely resembles that of a real railway. Such special functions can include, e.g., right-of-way indications, speed requirements, start/stop commands, braking and/or acceleration tasks and the like.
While a train is traveling the route, the sequential activation of and readout from the memory components, in particular transponders, with utilization of the route diagram or other representation deposited in the central memory, provides a coninuous determination of the position of the train on the railway by signals sent back to the central memory; in this process, with reference to prespecifiable tasks for operating the railway while taking into account the route and velocity information as well as the special functions, one or more machines are automatically monitored and controlled.
In the arrangement in accordance with the invention for the automatic or semiautomatic control of track-guided toys such as electric model railways and trains that is realistic and true to the original, the basic equipment consists of at least one memory unit with non-contact readout that is situated in or at the track, piece of track, buffer, signal and/or switch, such that the content deposited in the memory part of the memory unit specifies the type of product in each case plus a unique individual identifier. The type specification in the case of a track or track piece concerns, e.g., the length, the curve radius, the branching radius or angle in the case of switches, and the radius of the trunk track and that of the branch track in the case of curved switches.
The arrangement further comprises at least one memory-reading device in the model rolling stock, in particular the electrical machine, which additionally possesses a date-transmission means to pass the collected contents on when the machine reaches or travels over the memory unit.
The arrangement comprises in addition a superordinate central control and memory unit to determine position and velocity with reference to a detected or prespecified track diagram. As memory units transponders are preferentially employed, as mentioned above, and these can for instance be disposed in the track bed or connected in some other way so that they cannot be removed without destroying the above-mentioned products. The individual identifier deposited in the transponder consists of a sequence of numeric or alphanumeric symbols that is not repeated within the series of such sequences.
The rolling stock, in particular locomotive, comprises in accordance with the invention an electronic unit for activating and scanning transponder contents as well as a decoder and the above-mentioned data-transmission means. The latter is connected to the decoder, to which the scanned-in transponder contents are sent, the data-transmission means being designed as a hard-wired or wireless interface.
In addition, the rolling stock can contain a sensor to detect changes in the movement of the locomotive in the vertical and/or horizontal direction.
Another objective of the invention is to create and disclose a method, and components that can be employed therewith, that makes available to a user a plurality of possibilities with which to enhance the attractiveness of playing.
This objective of the invention is achieved by the characteristics given in Claim 19 .
One advantage derived from the characteristics cited in this claim resides in the fact that they enable partially or fully automatic control of track-guided toy vehicles on a model installation. The positional information provided with this method, i.e. the ability to observe events during operation of the toy, by which is meant the roadway and/or the toy vehicle as such, simultaneously permits these events to be visualized on a commercially available calculator unit, in particular a personal computer. In addition to these possibilities for observation/visualization, it is of course also possible on the basis of the evaluation unit, preferably designed as a personal computer, to undertake active intervention in or influencing of such events.
The objective of the invention is also independently achieved by the characteristics given in Claim 20 .
The advantages derived from the combination of characteristics in this claim reside in the fact that they enable an almost completely automatic collection of data for the representation of a roadway system with any desired structure, by simply traveling over the entire route network. The information that is read can be transmitted by simple means to a central evaluation apparatus and used by the latter for highly diverse processing, in particular to generate a virtual image of the installation.
A further development according to Claim 21 is advantageous in this regard, because it enables the data collection for representation of a route system to be undertaken almost entirely independently of user activities. Furthermore, the momentary position of the toy vehicle can be determined at any time.
As a result of the optional measures specified in Claim 22 , the precision can be increased and/or errors in the control or observation processes can be corrected.
By means of the measures according to Claim 23 and/or 24 , the visualization of roadway images, functional states and toy vehicles can be matched to the users particular desires or requirements.
The additional measures given in Claim 25 allow actions that enliven play, such as information broadcasting, light signals, traffic-direction signs and the like, to be activated.
By means of the measures according to Claim 26 a course of events resembling that in real traffic systems can be implemented by specifications in the form of timetables.
The objective of the invention is also and independently achieved by the characteristics given in Claim 27 .
The advantages derived from the combination of characteristics in this claim reside in the fact that without elaborate hardware or technology, in particular without complicated cable arrangements, a highly developed control and/or observation of toys, in particular toy vehicles guided by tracks on roadways, is made possible.
An independent way to achieve the objective of the invention is also specified by the characteristics given in Claim 28 .
The advantages derived from the combination of characteristics in this claim reside in the fact that the identification-code carriers, which are needed in relatively large numbers, are assigned to the relatively numerous railway components, which allows the overall costs of the system in accordance with the invention to be kept low. Moreover, the provision of a device to measure distances along the route makes possible a higher-resolution determination of position.
An independent way to achieve the objective of the invention is specified by the characteristics according to Claim 29 .
The advantages derived from the combination of characteristics in this claim reside in the fact that they create an economical basis for the automated control and observation of sequences of events in the course of play. Given that the identification-code carriers need merely to identify the type of a railway component, standardized code carriers that are relatively inexpensive to obtain can be employed. Because the amounts of data are comparatively small, code carriers with little storage capacity can be used. The individual identifier can then serve quasi as a pointer to more extensive data blocks or data sets, containing for example geometric data.
The further development according to Claim 30 achieves great flexibility in the assignment of functions or actions to particular roadway sections.
With the embodiment according to Claim 31 , mistakes by the user in connecting identification-code carriers to particular roadway components are excluded.
The characteristics according to Claim 32 make it possible to determine the relative position of a toy vehicle with reference to the roadway component.
By means of the measures given in Claim 33 a high degree of security against interference and transmission reliability of the type-specific identifiers is achieved.
The geometry of a complex route network can be determined with computer assistance for an evaluation device by associating the geometric data with the identifiers.
In the embodiment according to Claim 35 it is advantageous that such identifiers can be reliably detected with standard sensing systems.
In the embodiment according to Claim 36 it is advantageous that the code carriers need not be provided with an independent energy supply, but rather are designed as passive electronic components.
In the possible embodiment according to Claim 37 or 38 it is advantageous that the codes can be detected reliably even in the presence of severe interference from electromagnetic fields.
In the further development according to Claim 39 or 40 it is advantageous that the direction of a toy vehicle relative to the roadway route can be determined with reference to a single roadway component.
The objective of the invention is also independently achieved by the characteristics given in Claim 41 .
The advantages provided by the characteristics in this claim reside in the fact that a reading device with associated data-transmission means suffices to determine a position.
In the further development according to Claim 42 or 43 it is advantageous that extraneous influencing of the reading device by adjacent identification-code carriers can be avoided by simple means.
Provision of a cable system to constitute a means of data transmission from the toy vehicle to the evaluation unit that controls its activities is made unnecessary by the embodiment according to Claim 44 .
The measures according to Claim 45 make it possible by simple means to implement uni- or bidirectional transmission between the toy vehicle and an evaluation unit.
By means of the optional further development according to Claim 46 or 47 , supplementary items of information related, e.g., to height differences or changes of direction can be obtained.
Finally, a possible further development according to Claim 48 is advantageous because it enables the correction of errors and/or a high-resolution determination of position.
In the following the invention is explained with reference to exemplary embodiments, the description of which is assisted by drawings.
These figures represent the principles underlying the installation of transponders in or at the track, and illustrate the approach of a locomotive to a transponder. In simplified drawings,
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1 shows in principle how a transponder is mounted in or at the track, as well as a locomotive approaching the transponder;
FIG. 2 shows in principle the components required for the method in accordance with the invention for controlling a track-guided toy;
FIG. 3 shows another exemplary embodiment of the arrangement of the components essential for the method in accordance with the invention;
FIG. 4 shows a roadway component with an identification-code carrier permanently installed in a rail;
FIG. 5 shows a roadway component with an identification-code carrier installed in the track bed under a rail;
FIG. 6 shows a roadway component with an identification-code carrier installed in a sleeper;
FIG. 7 shows a roadway component with an identification-code carrier fixed to a track bed;
FIG. 8 shows a roadway component with an identification-code carrier in the form of a bar code attached to a track bed;
FIG. 9 shows a roadway component with an identification-code carrier in the form of a bar code attached to a sleeper;
FIG. 10 shows in principle a roadway component constructed as a branch point of a roadway and bearing several identification-code carriers;
FIG. 11 shows in principle a roadway component constructed as a branch point of a roadway and bearing a carrier for directional identification codes.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, wherein like references numerals designate identical or corresponding parts throughout the several views.
In or at the track 1 there is a transponder 2 that specifies the track's type and geometry, having been disposed in the relevant track section or on the track or during manufacture fixedly connected thereto, e.g. injected into the ballast or integrated into part of the track bed. The transponder 2 comprises, in addition to the type- and geometry-specifying data, an individual identifying code which is not repeated.
The locomotive 3 possesses a memory-reading device with antenna 4 and a data-transmission means 5 . The data-transmission means 5 creates a wireless connection to a receiver 6 and a central memory, which can be a component in a personal computer. On a monitor 7 a representation of the track is displayed, and the momentary position of each element of rolling stock on the route can be indicated there.
At the moment when the locomotive 3 comes within the transmission range of the transponder 2 , the high-frequency field generated by radiation from the antenna 4 excites the receiving antenna integrated into the transponder 2 , so that in a next step data can be read out from the transponder 2 and collected by the antenna 4 of the memory-reading device. The data and information thus obtained are then passed on, by way of a wireless transmission path, to the receiver 6 , which by referring to the known route details is capable of determining the position and velocity of the locomotive, and hence of the train.
The type- and geometry-specifying data stored in the transponder can be derived, for example, from the article-identification code associated with the track or piece of track, the individual identification code being a serial number assigned only once, so that each track piece that reaches the end user is uniquely identified and its geometry is specified.
In the exemplary embodiment shown here a wireless transmission path is assumed, but it is also possible to make use of a digital two-wire bus system, which is available in any case, to transmit this return signal.
Additional transponders can also be integrated into signals, switches or other equipment for operating the railway, so that when the train reaches such equipment, special functions are initiated, or a specified controlling or switching action is begun, or the equipment is tested for functionality.
On the whole, with the invention just described it is possible to create a real running operation for a model railway, in which it is possible to detect the position of the rolling stock with high precision. Owing to the properties of passive transponders no elaborate modifications are needed, nor is a supplementary electricity supply required at the track for the memory components disposed there, so that the equipment costs can be kept within limits. Maximally miniaturized encapsulated transponders have a diameter of about 2 mm and a length of ca. 10 mm, with a weight of about 0.1 to 0.25 g. The maximum distance at which transponders currently on the market can be read is in the region of 200 to 400 mm, which is sufficient for the application cases of interest here.
It should be kept in mind that in the following presentation of various embodiments identical parts are given the same component names and reference numerals, and accordingly what has been said in this description also applies below to the same parts, with the same names and reference numerals. Furthermore, in the following descriptions the details regarding position—such as above, below, at the side etc.—refer to the figure and represented structure that are currently being described, and when the orientation of the structure changes, such terms should be transferred appropriately to the new orientation. Individual features or combinations of features in these exemplary embodiments can represent solutions that are independent, inventive or in accordance with the invention.
FIG. 2 shows in principle the components that are essential for implementing the method in accordance with the invention for controlling a track-guided toy.
A toy vehicle 101 is situated on a roadway component 102 that forms a piece of a roadway; to this component are attached identification-code carriers 103 that are provided with an identifier 104 or that in themselves constitute an unmistakable, unique identifier. So that the identifiers 104 can be detected, the toy vehicle 101 is equipped with a reading device 105 , the identification-code carriers 103 being readable by non-contact means. The signals from the reading device 105 that correspond to the identifier 104 are sent to a data-transmission means 107 by way of a decoder 106 and pass from there along a transmission path 108 into an evaluation unit 109 . The transmission path 108 can either consist of a wire connection or be wireless. For the case of model railways a hard-wired system, e.g. by way of the rails of the track, is possible. When the transmission path 108 is designed to be wireless, the data exchange between the data-transmission means 107 and the evaluation unit 109 is accomplished, e.g., by radio with the assistance of corresponding antennae. The evaluation unit 109 can take several forms, e.g. comprising control software in a personal computer, in which case the information can be displayed on a monitor 110 . The toy vehicle 101 can optionally be equipped with a direction sensor 111 to detect directional changes, as well as a slope sensor 112 and a distance-measuring device 113 with which to determine the length of the part of the roadway over which the train has travelled. The data provided by the slope sensor 112 and the distance-measuring device 113 can be processed by the evaluation unit 109 so as also to determine the vertical position or height of the toy vehicle 101 , especially for roadways constructed at several different levels.
In the identification-code carriers 103 of a roadway component 102 are stored at least the type data for the component 102 . Different types of roadway components 102 would be, e.g., straight segments, branch points such as switches, intersections, or curved segments and similar components. The identifier 104 of a given type of roadway component is encoded by a sequence of numerical or alphanumeric symbols that is not repeated within the series of such sequences.
The identification-code carriers 103 are preferably transponders designed as passive electronic components. By means of a high-frequency field generated by an antenna of the reading device 105 the transponder is triggered to send out the identifier 104 , which can thus be detected by the reading device 105 . The identifier 104 in this case takes the form of an electrically or magnetically detectable feature. The transponder constructed as identification-code carrier 103 incorporates a transmitting and receiving antenna, control logic and a means of data and energy storage, but it need not have its own, autonomous electricity supply. The energy derived from the electromagnetic field of the transmission antenna in the reading device 105 suffices as electrical operating energy for the transponder.
As required by the small distances between the roadway components 102 of toys, the distances between the identification-code carriers 103 implemented as transponders are also relatively slight, so that in principle there is a risk that a reading device 105 will read out information from several identification-code carriers 103 simultaneously. To prevent this, the reading device 105 is constructed with a limited spatial range for reading from the identification-code carriers 103 . This can be accomplished by appropriately reducing the transmission power of the transmission antenna of the reading device 105 . In accordance with the size relationships customarily prevailing in model railways, the spatial range can be restricted to a distance between 0 mm and 50 mm, or preferably 0 mm to 30 mm.
It is of course also possible to construct systems comprising identification-code carriers 103 and reading devices 105 such that an identifier 104 is implemented by other features. For instance, the identification-code carrier 103 could be imprinted with a bar code, in particular a bar code that is visible only under UV light. A corresponding reading device 105 could in this case take the form of a bar-code scanner. In another embodiment of the invention it is also possible to use a reading device 105 designed for ultrasound sampling to identify the roadway component 102 . In this case the component 102 itself is the identification-code carrier, in that its external shape is used for identification.
FIG. 3 shows another exemplary embodiment of the arrangement of components essential for the method in accordance with the invention. Here the toy vehicle 101 moves on a roadway component 102 configured as a track, as is customary e.g. for model railways. The rails of the track can be used to supply the toy vehicle with the running voltage needed to drive the motor, but they can also be used for exchanging signals between the toy vehicle 101 and the evaluation unit 109 . The signals from the data-transmission means 107 in this case pass through the wheels of the toy vehicle 101 and the rails of the roadway component 102 and then in sequence along the transmission path 108 to the signal converter 114 . The signal converter 114 serves to convert the signals into a format that can be processed by the evaluation unit 109 and send them on to the evaluation unit. The signal converter 114 can be designed as an independent component or, if desired, as an interface card built into a personal computer. The transmission path 108 along which the signals pass between the rails of the roadway component 102 and the signal converter 114 can of course be either wireless or a wired connection.
FIGS. 4 to 7 show various arrangements of identification-code carriers 103 in a roadway component 102 such as is used for model railways. Here a roadway component 102 consists of a track 120 comprising rails 121 , sleepers 122 and a track bed 123 . The identification-code carriers 103 are preferably designed as transponders.
In the exemplary embodiment according to FIG. 4 , the identification-code carrier 103 is permanently incorporated into a rail 121 . In the exemplary embodiment according to FIG. 5 , the identification-code carrier 103 has been injected into the track bed 123 . It is likewise possible to incorporate the identification-code carrier 103 into the sleeper 122 (FIG. 6 ). It is evident that in the exemplary embodiments according to FIGS. 4 , 5 and 6 the identification-code carriers 103 can be removed only by destroying the roadway component 102 . As shown in FIG. 7 , however, it is also possible to attach an identification-code carrier 103 to a track-bed element 123 after the latter has been produced. For this purpose the track-bed element 123 of the roadway component 102 has been provided with an attachment device 124 , by means of which the identification-code carrier 103 can be fixed to the substructure of the roadway 102 . Fixation may constitute part of the manufacturing process, during production of the roadway component 102 , but the identification-code carrier 103 can also be attached later by the user. This enables the user to retrofit the toy individually with identification-code carriers 103 .
However, it is of course also possible merely to mount the identification-code carrier 103 on a part that is connected to the roadway component 102 , or to attach the identification-code carrier 103 within another part of the toy that is associated with the roadway component 102 , for instance a signalling light or traffic sign or similar constituent of the toy.
FIGS. 8 and 9 show exemplary embodiments of a roadway component 102 in which the identification-code carriers 103 are imprinted with a bar code. In this case the identification-code carrier 103 is attached to the track bed 123 ( FIG. 8 ) or to a sleeper 122 (FIG. 9 ). So as not to impair the external appearance of the roadway component 102 , this bar code is designed so as not to be visible to the human eye; for instance, it may be readable only under UV illumination.
FIGS. 10 and 11 represent in simplified form a roadway component 102 used at branch points of the roadway; in model railways, for instance, this would take the form of a switch. On this component multiple identification-code carriers 103 are arranged. In the exemplary embodiment according to FIG. 10 one identification-code carrier 103 is disposed in each of the end regions of the component. Because each of these identification-code carriers 103 bears an individual identifier 104 , it is possible for an approaching toy vehicle, by means of the reading device and appropriate evaluation in the evaluation unit in combination with the geometric data for the roadway component 102 , to determine the relative spatial position of the roadway component 102 .
FIG. 11 shows a branched roadway component with a directional identification-code carrier 126 composed of three identification-code carriers 103 . This arrangement of at least three identification-code carriers 103 enables an approaching toy vehicle to determine the relative spatial position of the roadway component 102 on the basis of the transit times of the signals between the reading device and the individual identification-code carriers 103 . This calculation requires the geometric data as well as the relative position of the directional identification-code carrier 126 to be stored in the evaluation unit. It is of course also possible to use directional identification-code carriers 126 that are not composed of an arrangement of several identification-code carriers 103 but rather bear identification-code carriers 103 that exhibit a physical feature from which the spatial position can be determined.
In order for the position of the toy vehicle to be determined in the evaluation unit, the latter must have available for each roadway component not only the type-specific geometry data, such as the length, radius, branching angle, branching radius, intersection angle and/or slope angle, but also the relative position of the identification-code carriers 103 , in particular distances 125 ( FIG. 10 ) from the end faces of the component. These distances 125 , like the geometric data, are uniform for each given type of roadway component.
The components shown in FIGS. 2 and 3 and the arrangements of the identification-code carriers 103 corresponding to FIGS. 4 to 11 enable automatic or semiautomatic control of a toy vehicle 101 that is guided along a roadway by tracks. For this purpose the roadway components 102 ( FIGS. 2 , 3 ) are provided with an identification-code carrier 103 , the identifier 104 of which specifies at least the type of the roadway component 102 , and the toy vehicles 101 are equipped with a reading device 105 for these identification-code carriers 103 . As is customary in model building, such a roadway is constructed from different types of components 102 . These include, for instance, straight track pieces, switches, intersections and the like. However, this control means is also suitable for toy vehicles guided on a roadway not by tracks, as in the case of a railway, but rather in some other way, for instance by an electronic or ferromagnetic guidance system recessed within the roadway.
Within the scope of the invention it is of course possible to assign the identification-code carriers, in particular a transponder, to a toy vehicle and to dispose a plurality of reading devices on the roadway side. These reading devices are preferably integrated into the roadway components, so as to be in electrically conductive connection with the rails of a constructed track system. The rail network in this track system is used as a two-wire bus, i.e. as a revertive-communication bus to the superordinate evaluation unit. For this purpose control signals can be produced by modulation of the driving voltage applied to the rail system. The essential point here is that the evaluation unit, in particular the personal computer, is in communication with the rails, e.g. by way of an interface card or other adapter device. Preferably the control elements present in a standard model railway, for example so-called locomotive mice, control panels etc., can be used here. These standard control systems can then be used as an accessory or an alternative to the input devices to the evaluation unit, e.g. a conventional keyboard.
When a toy vehicle travels on a newly constructed roadway for the first time, it is possible to obtain a representation of the entire course of the roadway by reading out the type-specific identifiers of the roadway components with the reading device. That is, once the geometrical data and directional information for each type of roadway component have been stored in the evaluation unit, as explained in the description of FIGS. 10 and 11 , then by identifying the individual roadway components in sequence, as their identifiers are detected by the traveling vehicle, and associating with each component its type-specific data, a virtual image of the roadway can be generated. When information obtained from the slope measurements made with the slope sensor and from the route distance measurements made with the corresponding measurement device is processed as well, an appropriate computational linking of the data can generate an overall three-dimensional image of the course of the roadway. In this way an individual characterization of the roadway components is present only in the virtual image of the roadway course produced by the evaluation unit. The relevant data can be saved, e.g., in a table in which the individual characterization of a roadway component is associated with the corresponding type-specific identifiers and the component's geometric and/or directional data. This table can also show the other functions associated with particular roadway components. Such functions make it possible to run the toy vehicles in a realistic way by assigning to particular route sections or roadway components specific properties, such as right-of-way or velocity specifications, start/stop commands, braking and/or acceleration tasks and the like.
Because the identifiers of the roadway components are continuously transmitted from the toy vehicle's reading device into the evaluation unit, the momentary position of the vehicle can be established at any time. The prespecified functions simultaneously allow the movements of the toy vehicles on the roadway and/or relative to other toy components to be monitored and influenced. By referring to the virtual diagram in the evaluation unit and determining the position of the toy vehicles it is thus also possible to display an image of the roadway on the monitor of a personal computer. At the same time the functional states of all components and those of the vehicle, as well as the vehicle itself, can be realistically displayed. The assignment of functions to route sections and/or individual roadway components also allows particular signal indications to be specified and/or actions involving the lights of the vehicle to be triggered. Because the control is mediated by a program deposited in the evaluation unit, it is also possible to operate the toy vehicles on the roadway route according to a timetable.
In one possible variant of an embodiment of the invention the identifiers disposed on the roadway components include information about the type of component but do not specify the component individually. In this case if a toy vehicle is taken off the roadway and set onto it again in a completely different place, as often happens, the problem arises that the capabilities of the evaluation unit initially inform it only about the type of roadway component on which the vehicle is seated, but not about the vehicle's current position when on that component. Identification of the actual position within the course of the roadway can be done either semiautomatically or automatically. That is, in the first case the operator can indicate its current position to the vehicle by means of the control program in the personal computer. On the other hand, it is possible to let the vehicle proceed from its initial, unknown position and under program control continuously compare the progressively lengthening sequences of roadway component identifiers with the pattern of component sequences stored in the evaluation unit. The number of possible matches between the new sequence of identified roadway components and individual sections of the known overall route becomes progressively smaller as the length of the new sequence increases, until finally only one possible match remains and the momentary position of the toy vehicle is thereby identified.
In another variant of an embodiment it is also possible to omit the attachment of an identification-code carrier to at least one type of roadway component. This is in any case appropriate for roadway components configured for a straight travel direction. Because all other types are equipped with an identification-code carrier, the momentary position of the toy vehicle can be unequivocally derived from the identifier of the code-equipped component that was last encountered and the distance covered since that encounter, which is measured by the distance-measuring device in the toy vehicle.
For clarity it should mentioned in conclusion that to assist understanding of the construction of the toy, in the drawings it and/or its parts are in some cases shown not to scale and/or enlarged and/or reduced in size.
The independent measures proposed in accordance with the invention to solve problems addressed by its objectives will be evident from the description.
Especially the individual embodiments shown in FIGS. 2 ; 3 ; 4 , 5 , 6 , 7 ; 8 , 9 ; 10 , 11 can constitute independent solutions in accordance with the invention. The relevant problems and solutions in accordance with the invention can be discerned in the detailed descriptions of these figures.
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 appended claims, the invention may be practiced otherwise than as specifically described herein.
LIST OF REFERENCE NUMERALS
1 Track
2 Transponder
3 Locomotive
4 Antenna
5 Data-transmission means for revertive communication
6 Receiving device and central memory
7 Monitor
8 Wireless transmission path
101 Toy vehicle
102 Roadway component
103 Identification-code carrier
104 Identifier
105 Reading device
106 Decoder
107 Data-transmission means
108 Transmission path
109 Evaluation unit
110 Monitor
111 Direction sensor
112 Slope sensor
113 Distance-measuring device
120 Track
121 Rail
122 Sleeper
123 Track bed
124 Attachment device
125 Separation distance
126 Directional identification-code carrier
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A method and an arrangement for the accurate, realistic automatic or semiautomatic control of track-guided toys, in particular electrically operated model railways and trains. Type- and/or geometry-specifying memory components, readable by non-contact, are disposed at or in each track, track piece, buffer, signal and/or switch that is to be included in the structure, such that each memory component and hence each track in addition exhibits an identification code that is not repeated within the series of such codes. Furthermore the rolling stock, preferably the locomotives, are equipped with a memory-reading device as well as a data-transmission device for revertive communication. After a first trip around the route, an electronic representation of the route configuration is available and can be preserved in a central memory. During subsequent trips around the route, the momentary position on the roadway or of the train is determined by reading memory components and revertive signalling to the central memory or a central control system, such that on the basis of prespecifiable tasks associated with operation of the railway, taking into account the route and velocity information as well as special functions, one or more machines are independently monitored and controlled.
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FIELD OF THE INVENTION
[0001] The present invention relates to compound storage vessel handling apparatus. Particularly, although not exclusively, the invention relates to a lifting head for handling microtubes.
BACKGROUND OF THE INVENTION
[0002] Contemporary drug development involves the preparation and storage of a large number of compounds, and subsequent later retrieval of selected compounds. Typically small quantities of compounds are stored in microtubes. The microtubes are stored in racks which are in turn stored in cold stores. Introduction of microtubes into a cold store and subsequent retrieval of selected microtubes is usually automated.
[0003] In our co-pending application number 0314686.7 a method and apparatus for handling microtubes are disclosed. The method is for handling a compound storage vessel disposed in a cavity in a rack, the cavity having an upper opening and a lower opening, and comprises the step of introducing a lifting pin into the cavity through the lower opening to urge the compound storage vessel upwards within the cavity. Correspondingly the apparatus is for handling a compound storage vessel disposed in a cavity in a rack, the cavity having an upper opening and a lower opening, and comprises a lifting pin and associated actuator, the lifting pin being arranged to be inserted into the cavity through the lower opening and operable by means of the actuator to urge the compound storage vessel upwards within the cavity.
[0004] Using a lifting pin enables individual compound storage vessels to be selected and raised within a rack.
[0005] In one embodiment the method is for removing a selected vessel or vessels from wrack and further comprises the step of locating a lifting head defining at least one cavity over the rack so that the at least one cavity is aligned with the cavity in the rack containing the selected vessel, raising the selected vessel out of its cavity in the rack by means of the lifting pin so that the vessel is introduced into the cavity in the lifting head such that the vessel becomes retained relative to the lifting head.
[0006] The lifting head and rack may then be moved apart and the lifting head placed over another rack such that the cavity or cavities in the lifting head containing selected vessels are aligned with cavities in the other rack. The or each vessel retained in the lifting head may then be displaced from the lifting head into the one or more cavities in the rack. The or each vessel is preferably arranged to be retained within a cavity of the receiving head by means of a friction fit.
[0007] It is an object of this invention to provide improved apparatus for handling compound storage vessels and particularly, although not exclusively, a lifting head for handling microtubes.
[0008] According to the present invention there is provided apparatus for handling compound storage vessels comprising at least one cavity for receiving a compound storage vessel, the or each cavity being associated with a respective detector operative to detect the presence of a compound storage vessel in the cavity.
[0009] Provision of a detector or detectors enables automated vessel handling apparatus to determine if a cavity is populated. This is particularly useful where the apparatus comprises a large number of cavities.
[0010] In one embodiment a detector comprises a first electrical contact arranged on introduction of a compound storage vessel into the cavity to be urged into contact with a second electrical contact, thereby to complete an electrical circuit to indicate the presence of a vessel in the cavity.
[0011] The or each cavity may include a resiliently biassed member extending into the cavity and operative to urge a vessel introduced into the cavity against a wall of the cavity thereby to help retain the vessel relative to the cavity. The resiliently biassed member may comprise a spring form which may be disposed in a slot formed in a wall of the cavity. Movement of the resiliently biassed member may be arranged to cause the first and second electrical contacts to come into contact. In one embodiment the resiliently biassed member comprises a spring form incorporating an electrical contact arranged, in use, to come into contact with a second contact disposed on a printed circuit board when a compound storage vessel is introduced into the cavity.
[0012] Preferably the apparatus forms a lifting head for lifting microtubes from a microtube storage rack.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order that the invention may be more clearly understood an embodiment thereof will now be described by way of example with reference to the accompanying drawings of which:
[0014] FIG. 1 is a side schematic cross-sectional view of a lifting head being used to remove microtubes from a microtube storage rack;
[0015] FIG. 2 is a cutaway perspective view of a microtube cavity of apparatus according to the invention;
[0016] FIG. 3 shows a side cross-sectional view of the cavity of FIG. 2 comprised in a lifting head;
[0017] FIG. 4 is a plan view of the cavity of FIG. 2 ; and
[0018] FIG. 5 shows how cavities of the shape illustrated in FIGS. 2 to 4 may be arranged together to form a lifting head having a plurality of such cavities.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0019] In the following description references to upper, lower, top bottom and the like refer to the apparatus as illustrated, and are not intended to be limiting in any other way.
[0020] FIG. 1 shows in general how a lifting head (whether or not it includes the present invention) is used in the selection of microtubes from a microtube rack. Referring to FIG. 1 , a microtube rack 1 defines a plurality of open topped cavities in each of which is disposed a microtube 2 . The bottom of each cavity is partially closed to provide support for the microtubes 2 whilst permitting a lifting pin 3 to be introduced into the cavity beneath the microtube 2 . Alignment pins 4 extend from the upper surface of the microtube 2 rack.
[0021] A lifting head 5 is used to remove selected microtubes 2 from the microtube rack 1 . The lifting head 5 defines a plurality of cavities 6 for receiving microtubes 2 . The cavities are sized so that the microtubes 2 fit into the cavities 6 with an interference fit. The cavities 6 are open to the bottom and at least partially open to the top to enable a pin to be introduced from above to displace any microtube 2 disposed in a cavity of a lifting head 5 out of the cavity through its lower opening. The underside of the lifting head includes alignment apertures 7 .
[0022] When it is desired to remove selected microtubes from the microtube rack the lifting head 5 is placed over the rack so that the cavities of the lifting head and the cavities of the rack are aligned and alignment pins 4 are received into alignment holes 7 . Selected microtubes 2 are then raised out of their cavities in the rack and urged into the corresponding cavity of the lifting head 5 by means of a lifting pin 3 introduced into the cavity in the rack from below. The lifting head 5 can then be removed from the rack 1 with the selected microtubes 2 retained within cavities of the lifting head. Subsequently the lifting head may be placed over another rack and the microtubes 2 retained in the lifting head displaced from the lifting head into the new rack by means of pins introduced into the cavities of the lifting head 1 from above.
[0023] Features of a lifting head of an embodiment of the present invention having a plurality of cavities are shown in FIGS. 2 to 5 . For simplicity only a single cavity is shown in FIGS. 2 to 4 . Referring to FIGS. 2 to 5 each cavity 8 is of a generally keyhole shaped cross-section. Each cavity 8 comprises a portion of substantially circular cross-section and a portion of substantially rectangular section, formed by a longitudinal slot extending in a wall of a substantially circular cavity. The portion of the cavity 8 of substantially circular cross-section is intended to accommodate a microtube, which should ideally have a close sliding fit within this portion of the cavity.
[0024] A spring form 9 is disposed within the slot of the cavity 8 . The spring form 9 is formed from a suitable electrically conductive material, for example Beryllium Copper. One end of the spring form 9 is flattened and fixed within the slot of the cavity so that it cannot move relative to the slot. This end of the spring form 9 is fixed by way of a detent 10 , although any other suitable means of fixing may be employed. The spring form 9 extends from the flat portion in an arcuate fashion. The arcuate portion of the spring form 9 extends out of the slot into the portion of the cavity 8 of substantially circular cross-section and back into the slot where a second flattened portion of spring form is found leading to a tail, having an electrical contact surface, the tail extending out of the slot.
[0025] In a microtube lifting head each cavity extends between top 13 and bottom 14 plates. The bottom plate 14 includes a plurality of substantially circular apertures 15 each one disposed concentrically with and substantially the same size as the circular portion of a respective cavity 8 so that microtubes may enter and leave each cavity through the bottom plate 14 . The top plate 13 also includes a plurality of substantially circular apertures 16 concentric with the substantially circular potion of each cavity. In contrast to the top plate though each aperture 16 has a diameter sufficiently smaller than that of the substantially circular portion of each cavity so that microtubes will not pass through the top plate 13 but a pin of smaller diameter than the microtubes can do so in order to displace microtubes from the cavity 8 . Further apertures 19 (which may connect with the substantially circular apertures 16 ) are formed in the top plate 13 through which the spring form 9 of each cavity extends. The tail portion 11 of each spring form extends at right angles to the longitudinal axis of the cavity 8 . Adjacent but spaced apart from the tail portion 11 of each spring form is an electrical contact 17 comprised in a printed circuit board 18 .
[0026] In use a microtube is introduced into the cavity 8 through aperture 15 in the bottom plate 14 . As the microtube substantially fills the portion of the cavity of circular cross-section as it moves into the cavity 8 it comes into contact with the arcuate portion of the spring form 9 . This causes the spring form 9 to deform. As the spring form 9 deforms the arcuate portion becomes flattened the effect of which is to urge opposite ends of the spring form 9 apart. The lower flattened end of the spring form cannot move relative to the slot in which it is disposed, both because of detent 10 and because the end of the spring form 9 is in contact with the bottom plate 14 . The upper flattened end of the spring form is, however, able to move since it can pass through aperture 19 in the upper plate 13 . This causes the tail 11 of the spring form to move towards electrical contact 17 and electrical contact 12 to make contact with contact 17 . This completes an electrical circuit enabling automatic microtube handling apparatus to determine that a microtube is present in the cavity 8 .
[0027] The spring form 9 serves a dual function. When a microtube is inserted into the cavity 8 the spring form 9 urges the microtube towards the opposite wall of the cavity ensuring a good friction fit between the microtube and cavity and therefore that the microtube is retained within the cavity. Secondly the spring form acts, in conjunction with electrical contact 17 , as an electrical switch which is closed when a microtube is introduced into the cavity and reopens when a microtube is displaced out of the cavity owing to the fact that the spring form will return to its original shape on removal of the microtube.
[0028] The keyhole shape of the cavities enables a plurality of cavities to be arranged closely together, in a manner illustrated in FIG. 5 . In one practical embodiment the centre points of the circular portion of each cavity are spaced apart by 4.5 mm. Whilst an array of 140 cavities has been illustrated apparatus can be provided with any convenient number of cavities.
[0029] The above embodiment is described by way of example only. Many variations are possible without departing from the invention as defined by the following claims.
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Apparatus for handling compound storage vessels such as microtubes having a least one cavity for receiving a compound storage vessel. Each cavity is associated with a respective detector operative to detect the presence of a storage vessel in the cavity. The detector may comprise a spring form extending in the cavity and arranged to be deformed by a storage vessel when introduced into the cavity, and further arranged so that on deformation it closes an electrical switch indicating the presence of the microtabe in the cavity. The presence of the spring form also increases friction between the storage vessel and the cavity retaining the storage vessel within the cavity.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of, claims priority to and the benefit of, U.S. Ser. No. 13/618,418 filed Sep. 14, 2012 and entitled “SYSTEM AND METHOD FOR AUTOMATICALLY GENERATING COMPUTER CODE FOR MESSAGE FLOWS.” The '418 application is a continuation of, claims priority to and the benefit of, U.S. Ser. No. 11/862,463 filed Sep. 27, 2007 and entitled “SYSTEM AND METHOD FOR AUTOMATICALLY GENERATING COMPUTER CODE FOR MESSAGE FLOWS,” which issued as U.S. Pat. No. 8,286,189 on Oct. 9, 2012. All of these applications are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to message flows in a message queuing infrastructure, and more particularly to a system and method for automatically generating computer code for message flows.
[0004] 2. Related Art
[0005] The information technology infrastructure of a large business can encompass a variety of different technologies, including different hardware platforms, programming languages, operating systems, and communication protocols. Middleware helps to form these different technologies into a coherent system by providing a common layer to bridge components across the infrastructure. Message queuing is a type of middleware technology that simplifies communication between the components, or nodes, of a system. A node is any point in the system that provides a service, requests a service, or connects nodes together.
[0006] Message queuing middleware, such as IBM WebSphere® MQ (WMQ) and IBM WebSphere® MQ Integrator (WMQI), provides integration for applications and Web services by allowing software applications to provide and request services residing on different nodes through the use of messages. Nodes send information and request services by sending messages to other nodes. Specifically, a message from a source node is placed in an input queue of a message broker. The message broker retrieves the message from the input queue, parses the message, and executes operations (e.g., transformation and routing) according to a message flow associated with the message. Once the operations of the message flow are completed for the message, the broker delivers the message to one or more output queues for retrieval by one or more destination nodes.
[0007] A message flow is a collection of nodes that provide small, reusable pieces of functionality for transmitting the message. Specifically, the nodes of a message flow define the series of operations and rules that the message broker executes for a message. Using message flows to communicate messages provides several advantages, particularly in a large enterprise infrastructure built on different technologies. For example, message flow nodes can be created to allow the broker to transform an input message in one format (e.g., Extensible Markup Language (XML)) to an output message in another format (e.g., MRM message). This ability to transform the format of a message facilitates communication between nodes that use different message formats. Message flow nodes can also be created to allow the broker to route an input message by, for example, setting destination queues and appending additional information to the message.
[0008] Generally, creating nodes for a message flow requires a human operator to write and test computer code. For example, WMQI allows users to create user-written nodes by inputting Extended Structured Query Language (ESQL) code into a node. ESQL is an extended version of Structured Query Language (SQL), which is a standard interactive and programming language for getting information from and updating a database. Although SQL is both an ANSI and an ISO standard, many database products support SQL with proprietary extensions to the standard language. Queries take the form of a command language that provides the ability to select, insert, update, find out the location of data, and so forth. SQL also includes a programming interface. Particularly, SQL includes a Microsoft Open Database Connectivity (ODBC) compatible interface, which allows custom applications to be built using a wide variety of programming tools or to query databases using existing ODBC-compliant applications.
[0009] In typical enterprise middleware infrastructure projects, the build time for each message flow node (in WMQI) can be relatively long. Thus development time for each message flow increases. In addition, maintaining consistency of the computer code written for different message flows from one project to another can be difficult. Moreover, errors in writing code for one project can be copied into code written for another project, causing the same defects to be repeated in the resulting message flows, which in turn increases development time due to re-work. Furthermore, it is often the case that the same or similar code written for one project cannot easily be used for another project due to the lack of knowledge of the existence of the already written code, which can result in duplication of effort.
[0010] Given the foregoing, what is needed is a system, method and computer program product for automatically generating computer code for message flows.
BRIEF DESCRIPTION OF THE INVENTION
[0011] The present invention meets the above-identified needs by providing a system, method and computer program product for automatically generating computer code for message flows.
[0012] An advantage of the present invention is that it speeds up development of message flows.
[0013] Another advantage of the present invention is that it improves productivity, particularly in situations with complex message flows having large numbers of fields that require mapping.
[0014] Yet another advantage of the present invention is that it reduces human errors and hence reduces defects during integration testing and user acceptance testing.
[0015] Still another advantage of the present invention is that it reduces development costs and time to market for developers of message flows and hence reduces the overall cost for integrating a business information technology infrastructure.
[0016] In one aspect of the present invention, computer-executable code is automatically generated for a message flow in a message queuing infrastructure. A type of the message flow is determined form user input. For example, a user can select from among a plurality of message flow types displayed on a graphical user interface. Message flow types can be selected, for example, for scenarios in which an XML application requests a service from a COBOL application, a COBOL application requests a service from an XML application, and an XML application requests a service from an XML application. Message flow parameters are input, for example, using a submenu of the graphical user interface. The computer-executable code for the message flow is automatically generated based on the determined type of the message flow and the input message flow parameters. For example, using the user's inputs, a computer can automatically generate ESQL script for use in the desired message flow.
[0017] In another aspect of the invention, a design pattern is input based on the determined type of message flow, and the computer-executable code generation is further based on the design pattern.
[0018] In still another aspect of the invention, the type of the message flow identifies a transformation requirement of the message flow based on the message flow parameters.
[0019] In yet another aspect of the invention, the conversion requirement is one of (i) transformation from a first Extensible Markup Language (XML) message to a second XML message, (ii) transformation from an XML message to a Message Repository Manager (MRM) message, and (iii) transformation from a first MRM message to a second MRM message.
[0020] In a further aspect of the invention, the determining the type of message flow includes determining a requestor type of the message flow and a provider type of the message flow, and the type of the message flow is determined based on the requestor type and the provider type.
[0021] In yet another aspect of the invention, the requestor type is one of an Extensible Markup Language (XML) requestor and a Common Business Oriented Language (COBOL) requestor, and the provider type is one of an XML provider and a COBOL provider.
[0022] In another aspect of the invention, a graphical user interface is displayed. The graphical user interface includes data entry fields for the input of the message flow parameters.
[0023] Further features and advantages of the present invention as well as the structure and operation of various embodiments of the present invention are described in detail below with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The features and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference numbers indicate identical or functionally similar elements. Additionally, the left-most digit of a reference number identifies the drawing in which the reference number first appears.
[0025] FIG. 1 is a system diagram of an exemplary enterprise system in which computer code generated according to the present invention would be implemented.
[0026] FIG. 2 is a block diagram of an exemplary computer system useful for implementing the present invention.
[0027] FIG. 3 is a flowchart illustrating an ESQL generating process according to one embodiment of the present invention.
[0028] FIG. 4 is a screenshot of a graphical user interface according to one embodiment of the present invention.
[0029] FIG. 5 is another screenshot of a graphical user interface according to one embodiment of the present invention.
[0030] FIG. 6 is another screenshot of a graphical user interface according to one embodiment of the present invention.
[0031] FIG. 7 is a system diagram illustrating an exemplary multi-hub architecture used by an exemplary design pattern of one embodiment of the present invention.
DETAILED DESCRIPTION
I. Overview
[0032] The present invention is directed to a system, method and computer program product for automatically generating computer code for message flows. Message flows are commonly utilized by enterprise systems implementing message queuing middleware. A common architecture of such an enterprise system is the so-called hub-and-spoke architecture. Hub-and-spoke architectures consist of a centralized hub that accepts requests from multiple applications that are connected to the centralized hub as spokes. The spokes are generally connected with the central hub through lightweight connectors, which are constructed and deployed on top of existing systems and applications.
[0033] Inside the hub there are multiple nodes that perform functions such as message transformation, validation, routing, and asynchronous message delivery. Some hub-and-spoke-based systems provide process management functionality to orchestrate interapplication message exchanges, and an administration console to monitor and track the workings of the hub.
[0034] FIG. 1 is a system diagram of an exemplary enterprise system in which computer code generated by the present invention may be implemented. FIG. 1 shows a hub and spoke architecture with clients 101 a, 101 b, 101 c and 101 d at the spokes and a message broker 103 at the hub. The clients 101 a, 101 b, 101 c and 101 d are connected to message broker 103 through network connections 105 a, 105 b, 105 c and 105 d, respectively, which allows messages to be communicated between the components of enterprise system 100 . Each client 101 a - d has WMQ installed and the message broker 103 has both WMQ and WMQI installed. In this configuration, the message broker 103 is used for transforming messages into alternate formats and routing the messages to the various clients 101 a - d in accordance with message flows.
[0035] The present invention is now described in more detail herein in terms of exemplary embodiments that generate ESQL scripts to be used in message flows implemented in the enterprise system of FIG. 1 . In particular, the exemplary embodiments generate ESQL scripts for transforming and routing messages transmitted among XML applications and COBOL applications in the enterprise system. The use of exemplary embodiments of the present invention is for convenience only and is not intended to limit the application of the present invention. In fact, after reading the following description, it will be apparent to one skilled in the relevant art(s) how to implement the following invention in alternative embodiments (e.g., generating computer code to be used in message flows for performing other operations, such as filtering messages, adding data to messages, subtracting data from messages, and storing messages, the messages being transmitted among applications built on a wide variety of platforms, operating systems, communication protocols, and programming languages, implemented with different message queuing middleware such as Microsoft® Message Queuing Server, Oracle® Advanced Queuing, and Apache® ActiveMQ, which operate within different enterprise system architectures, such as queue manager clusters, message bus, etc., and for other types of requesting applications, such as BLOB messages).
[0036] The terms “user,” “end user,” “consumer,” “customer,” “operator,” and/or the plural form of these terms are used interchangeably throughout herein to refer to those persons or entities capable of accessing, using, being affected by and/or benefiting from the tool that the present invention provides for automatically generating computer code for message flows.
[0037] Furthermore, the terms “business” or “merchant” may be used interchangeably with each other and shall mean any person, entity, distributor system, software and/or hardware that is a provider, broker and/or any other entity in the distribution chain of goods or services. For example, a merchant may be a grocery store, a retail store, a travel agency, a service provider, an on-line merchant or the like.
II. System
[0038] FIG. 2 is a system diagram of an exemplary computer system 200 in which the present invention, in an embodiment, would be implemented. Computer system 200 can be a client 101 in enterprise system 100 , or can be a stand-alone computer system.
[0039] The computer system 200 includes one or more processors, such as processor 204 . The processor 204 is connected to a communication infrastructure 206 (e.g., a communications bus, cross-over bar, or network). The processor 204 executes software code stored in one of a plurality of memories, described more fully below. Various software embodiments are described in terms of this exemplary computer system. After reading this description, it will become apparent to a person skilled in the relevant art(s) how to implement the invention using other computer systems and/or architectures.
[0040] Computer system 200 can include a display interface 202 that forwards graphics, text, and other data from the communication infrastructure 206 (or from a frame buffer not shown) for display on a display unit 230 .
[0041] Computer system 200 also includes a main memory 208 , preferably random access memory (RAM), and may also include a secondary memory 210 . The secondary memory 210 may include, for example, a hard disk drive 212 and/or a removable storage drive 214 , representing a floppy disk drive, a magnetic tape drive, an optical disk drive, etc. The removable storage drive 214 reads from and/or writes to a removable storage unit 218 in a well-known manner. Removable storage unit 218 represents a floppy disk, magnetic tape, optical disk, etc. which is read by and written to by removable storage drive 214 . As will be appreciated, the removable storage unit 218 includes a computer usable storage medium having stored therein computer software and/or data.
[0042] In alternative embodiments, secondary memory 210 may include other similar devices for allowing computer programs or other instructions to be loaded into computer system 200 . Such devices may include, for example, a removable storage unit 222 and an interface 220 . Examples of such may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an erasable programmable read only memory (EPROM), or programmable read only memory (PROM)) and associated socket, and other types of removable storage units 222 and interfaces 220 , which allow software and data to be transferred from the removable storage unit 222 to computer system 200 .
[0043] Computer system 200 may also include a communications interface 224 . Communications interface 224 allows software and data to be transferred between computer system 200 and external devices. Examples of communications interface 224 may include a modem, a network interface (such as an Ethernet card), a communications port, a Personal Computer Memory Card International Association (PCMCIA) slot and card, etc. Software and data transferred via communications interface 224 are in the form of signals 228 which may be electronic, electromagnetic, optical or other signals capable of being received by communications interface 224 . These signals 228 are provided to communications interface 224 via a communications path (e.g., channel) 226 . This channel 226 carries signals 228 and may be implemented using wire or cable, fiber optics, a telephone line, a cellular link, a radio frequency (RF) link and other communications channels.
[0044] In this document, the terms “computer program medium” and “computer usable medium” are used to generally refer to media such as removable storage drive 214 , a hard disk installed in hard disk drive 212 , and signals 228 . These computer program products provide software to computer system 200 . The invention is directed to such computer program products.
[0045] In one embodiment, computer programs (also referred to as computer control logic) are stored in main memory 208 and/or secondary memory 210 . Computer programs may also be received via communications interface 224 . Such computer programs, when executed, enable the computer system 200 to perform the various features of the present invention, as discussed herein. In particular, the computer programs, when executed, enable the processor 204 to perform features of the present invention. Accordingly, such computer programs represent controllers of the computer system 200 .
[0046] In the present embodiment, the invention is implemented using software. The software may be stored in a computer program product and loaded into computer system 200 using removable storage drive 214 , hard drive 212 or communications interface 224 . The control logic (software), when executed by the processor 204 , causes the processor 204 to perform the functions of the invention as described herein.
[0047] To generate computer code for message flows according to the present embodiment, a user executes the software on computer system 200 . Communications interface 224 can allow the user to upload the generated computer code to the enterprise system 100 of FIG. 1 , for use in message flows implemented by enterprise system 100 .
III. Process
[0048] FIG. 3 is a flowchart illustrating a computer code generating process 300 , according to one embodiment of the present invention. Specifically, the present embodiment generates ESQL scripts for use in a message flow.
[0049] Process 300 begins when a user identifier (ID), which has previously been stored in a registry, is obtained ( 301 ) from the registry. The user is prompted ( 302 ) to enter a password corresponding to the user ID. A determination is made ( 303 ) whether the user ID and password are valid. If the user ID or password could not be validated, then a determination is made ( 304 ) as to whether too many login attempts, for example, more than three, have been made. If not, then process 300 again prompts ( 302 ) the user for a password. However, if too many login attempts have been made, the application is closed ( 305 ) and process 300 ends. If the user ID and password are validated, a determination is made ( 306 ) as to whether the latest version of the software application in accordance with the present embodiment of the invention is being used. If not, the user is prompted ( 307 ) to install the latest version of the application. If the latest version of the application is in use, a selection is made ( 308 ) of the type of format transformation required for a message.
[0050] In the present embodiment, the transformation type is selected by the user based on the type of format transformation, if any, that is required for a message from an application requesting a service to an application providing the service. A code generator is set corresponding to the selected transformation type, and message flow parameters are then input by the user. An example of how the user selects the transformation type and inputs message flow parameters will now be described in reference to FIGS. 4 , 5 and 6 .
[0051] FIG. 4 is a screenshot of a menu 401 of an exemplary software embodiment of the present invention displayed on display unit 230 at step 308 . Menu 401 includes tabs for the selection of a transformation type 403 . The transformation types of the present embodiment are “XML To XML”, “MRM Request To XML”, and “XML To MRM Request”. For a request message from an XML application to another XML application, in which no format transformation is required, the user selects the “XML To XML” tab, and then inputs corresponding message flow parameters. Specifically, the user inputs a flow type 405 as “Request” or “Reply,” hub hopping information 407 as “App Hub” or “Service Hub,” a hub name 409 , a reply to queue 411 , and an XML envelope version 413 .
[0052] Referring again to FIG. 3 , after the user completes the user inputs, and selects the “Generate Script” button of menu 401 , a code generator for XML to XML ( 309 ), which corresponds to the user selected “XML To XML” tab, accepts ( 310 ) the message flow parameters from menu 401 , and generates ESQL script ( 311 ) for routing operations.
[0053] In a like manner, the user can select a tab for “XML To MRM Request” of menu 401 . Thus, FIG. 5 is a screenshot of a menu 501 of the exemplary software embodiment of the present invention displayed on display unit 230 at step 308 . For a request message from an XML application to a COBOL application, the user sets transformation type 403 by selecting the “XML To MRM Request” tab, and then inputs corresponding message flow parameters. In the present embodiment, messages sent to and received from COBOL applications are formatted as MRM messages. Specifically, the message flow parameters the user inputs are flow type 405 as “Request” or “Reply,” hub name 409 , reply to queue 411 , XML envelope version 413 , an MQ header type 503 , a COBOL format 505 , and an XML format 507 .
[0054] Referring again to FIG. 3 , after the user completes the user inputs, and selects the “Generate Script” button of menu 501 , a code generator for XML to MRM ( 312 ), which corresponds to the user selected “XML To MRM Request” tab, accepts ( 313 ) the message flow parameters from menu 501 , and generates ESQL script ( 311 ) for routing operations and transformation operations.
[0055] In a like manner, the user can select a tab for “MRM Request To XML” of menu 401 . Thus, FIG. 6 is a screenshot of a menu 601 of the exemplary software embodiment of the present invention displayed on display unit 230 at step 308 . For a request message from a COBOL application to an XML application, the user sets transformation type 403 by selecting the “MRM Request To XML” tab, and then inputs corresponding message flow parameters. Specifically, the user inputs flow type 405 as “Request” or “Reply,” hub name 409 , reply to queue 411 , XML envelope version 413 , COBOL format 505 , XML format 507 , and a latest copybook format 603 .
[0056] Referring again to FIG. 3 , after the user completes the user inputs, and selects the “Generate Script” button of menu 601 , a code generator for MRM to XML ( 314 ), which corresponds to the user selected “MRM Request To XML” tab, accepts ( 315 ) the message flow parameters from menu 501 , and generates ESQL script ( 311 ) for routing operations.
[0057] After ESQL script has been generated, the application closes ( 305 ) and process 300 ends.
[0058] In order to generate ESQL script for transformation and routing of a message, the code generators 309 , 312 , and 314 of the present embodiment implement a design pattern. While the use of a design pattern is not required, and the invention is not limited the use of a design pattern, the automatic generation of code according to a design pattern can provide many advantages. In particular, adherence to a design pattern results in more consistent WMQ and WMQI object naming and deployment, which can reduce the time and effort necessary to develop and support all messages flows. In addition, adherence to a design pattern can result in decoupling of components that request and components that provide services. In this regard, the design pattern of the present embodiment provides the code generators with (i) a standard coding practice for WMQ and WMQI objects, (ii) standard application processing requirements to be used in generating the ESQL script, and (iii) standard WMQI processing requirements to be used in generating the ESQL script.
[0059] The exemplary design pattern utilized in the present embodiment employs a logical multi-hub architecture, which is consistent with the current trend of decentralizing the processing in a WebSphere®-implemented enterprise system. In addition, all inter-hub messages are in canonical format and queues carry service names to facilitate redeployment to accommodate component and service changes. Use of the design pattern allows message flow developers and service providers to concurrently support multiple versions of each service message, which helps isolate service providers, message brokers, and requesters from the impact of new service versions. In particular, each can upgrade in an orderly fashion as business requirements dictate.
[0060] In addition, the exemplary design pattern of the present embodiment utilizes generic request and reply queues for applications and services, which can greatly reduce the number of WMQ objects to define and support, which allows new services to be employed by existing applications with minimal or no WMQ changes. Moreover, the use of generic request and reply flows for applications and services can greatly reduce the number of WMQI objects to define and support, which allows existing services to be employed by additional applications with minimal or no WMQI changes.
[0061] FIG. 7 depicts an exemplary multi-hub architecture on which the design pattern of the present embodiment is based.
[0062] FIG. 7 includes a requesting application 701 having the name “REQUESTER,” an application hub 703 having the name “APPHUB,” a service hub 705 having the name “SERVICEHUB,” and a provider application service 707 having the name “PROVIDER.” In this multi-hub architecture, a request message from requesting application 701 is routed through application hub 703 and service hub 705 to provider application service 707 . A reply message from provider application service 707 is routed through service hub 705 and application hub 703 to requesting application 701 .
[0063] In FIG. 7 , the paths of the messages are shown by the arrowed lines. Specifically, to request a service of provider application 707 , requesting application 701 places a request message in a queue 717 . The request message is routed through application hub 703 and service hub 705 to reach a queue 723 of provider application service 707 .
[0064] When provider application service 707 has completed processing the request message, a reply message is routed through service hub 705 and application hub 703 to reach a queue 729 of requesting application 701 .
[0065] The exemplary design pattern of the present embodiment provides a standard pattern for generating ESQL script for each portion of a request message flow, which includes a service request 731 from a requester, a request flow 733 on an application hub, a request flow 735 on a service hub, and a service request 737 to a provider. The exemplary design pattern of the present embodiment also provides a standard pattern for generating ESQL script for each portion of a reply flow, which includes a service reply 739 from a provider, a reply flow 741 on a service hub, a reply flow 743 on an application hub, and a service reply 745 to a requester. The message flows can include subflows, which define additional operations to be performed on a message. For example, subflows can be used for message format transformation. In addition, the message flows can include operations to set the destination of a message
[0066] In the present embodiment, requesting application 701 can be an XML application or a COBOL application. Likewise, provider application service 707 can be an XML application or a COBOL application. The particular combination of type of requesting application 701 and type of provider service application 707 is used to determine which code generator 309 , 312 , or 314 will be used to generate ESQL script for a message flow. In this regard, the operation of the code generators 309 , 312 , and 314 , and the implementation of the exemplary design pattern, will now be described with respect to particular combinations of types of requesters and providers.
[0000] XML requester—XML provider:
[0067] If both requesting application 701 and provider application service 707 are XML applications, XML to XML code generator 309 is used to generate ESQL script. Code generator 309 utilizes two XML to XML design patterns to generate ESQL script, a request message flow design pattern and a reply message flow design pattern.
[0068] When the flow type 405 selected by the user is “Request,” the XML to XML design pattern according to a request message flow is implemented by code generator 309 to generate ESQL script for request flow 733 on the application hub and request flow 735 on the service hub. The generated ESQL script for request flow 733 includes code defining a request queue, reverse routing information of the request message, compute and output nodes, a destination mode, a destination queue name, a reply to queue and a queue manager. The generated ESQL script for request flow 735 includes code defining a service request queue, reverse routing information, an application service provider input queue, and a reply to queue on service hub 705 .
[0069] When the flow type 405 selected by the user is “Reply,” the XML to XML design pattern according to a reply message flow is implemented by code generator 309 to generate ESQL script for reply flow 741 on the service hub and reply flow 743 on the application hub. The generated ESQL script for reply flow 741 includes code defining a service reply queue and routing replies to application hub 703 . The generated ESQL script for reply flow 743 includes code routing replies to requesting application 701 .
[0000] XML requester—COBOL provider:
[0070] If requesting application 701 is an XML application and provider application service 707 is a COBOL application, XML to MRM code generator 312 is used to generate ESQL script. Code generator 312 utilizes two XML to MRM design patterns to generate ESQL script, a request message flow design pattern and a reply message flow design pattern.
[0071] When the flow type 405 selected by the user is “Request,” the XML to MRM design pattern according to a request message flow is implemented by code generator 312 to generate ESQL script for request flow 733 on the application hub and request flow 735 on the service hub. The generated ESQL script for request flow 733 includes code defining a request queue, reverse routing information, compute and output nodes, a destination mode, a destination queue, a reply to queue and queue manager. The generated ESQL script for request flow 735 includes code defining a service request queue, reverse routing information, one or more sub-flows to transform the request from XML to the corresponding version of the COBOL service request message, a reply to queue on service hub 705 , and routing the request to an input queue on provider application service 707 .
[0072] When the flow type 405 selected by the user is “Reply,” the XML to MRM design pattern according to a reply message flow is implemented by code generator 312 to generate ESQL script for reply flow 741 on the service hub and reply flow 743 on the application hub. The generated ESQL script for reply flow 741 includes code defining a service reply queue, one or more sub-flows to transform the reply from COBOL to the corresponding version of the XML service reply message, and routing replies to application hub 703 . The generated ESQL script for reply flow 743 includes code routing replies to requesting application 701 .
[0000] COBOL requester—XML provider:
[0073] If requesting application 701 is a COBOL application and provider application service 707 is an XML application, MRM to XML code generator 314 is used to generate ESQL script. Code generator 314 utilizes two MRM to XML design patterns to generate ESQL script, a request message flow design pattern and a reply message flow design pattern.
[0074] When the flow type 405 selected by the user is “Request,” the MRM to XML design pattern according to a request message flow is implemented by code generator 314 to generate ESQL script for request flow 733 on the application hub and request flow 735 on the service hub. The generated ESQL script for request flow 733 includes code defining a request queue, reverse routing information, one or more sub-flows to route requests to a corresponding service request queue on service hub 705 , a reply to queue and queue manager. The generated ESQL script for request flow 735 includes code defining a service request queue, reverse routing information, and a reply to queue on service hub 705 , and routing requests to an input queue on provider application service 707 .
[0075] When the flow type 405 selected by the user is “Reply,” the MRM to XML design pattern according to a reply message flow is implemented by code generator 314 to generate ESQL script for reply flow 741 on the service hub and reply flow 743 on the application hub. The generated ESQL script for reply flow 741 includes code defining a service reply queue, and routing replies to application hub 703 . The generated ESQL script for reply flow 743 includes code defining a reply queue, one or more sub-flows to route reply messages back to the requesting application 701 and to transform the XML reply to the corresponding COBOL copybook of the service reply.
[0076] By using the above exemplary design patterns, the code generators of the present embodiment can generate consistent ESQL code for use in message flows. However, the foregoing design pattern is merely one example, and one skilled in the art would recognize that other design patterns, or none at all, could be used.
IV. Example Implementations
[0077] The present invention (i.e., computer system 200 , process 300 , or any part(s) or function(s) thereof) may be implemented using hardware, software or a combination thereof and may be implemented in one or more computer systems or other processing systems. However, the manipulations performed by the present invention were often referred to in terms, such as adding or comparing, which are commonly associated with mental operations performed by a human operator. No such capability of a human operator is necessary, or desirable in most cases, in any of the operations described herein which form part of the present invention. Rather, the operations are machine operations. Useful machines for performing the operation of the present invention include general purpose digital computers or similar devices.
[0078] In another embodiment, the invention is implemented primarily in hardware using, for example, hardware components such as application specific integrated circuits (ASICs). Implementation of the hardware state machine so as to perform the functions described herein will be apparent to persons skilled in the relevant art(s).
[0079] In yet another embodiment, the invention is implemented using a combination of both hardware and software.
V. Conclusion
[0080] While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be apparent to persons skilled in the relevant art(s) that various changes in form and detail can be made therein without departing from the spirit and scope of the present invention. Thus, the present invention should not be limited by any of the above described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.
[0081] In another embodiment, the invention is implemented primarily in hardware using, for example, hardware components such as application specific integrated circuits (ASICs). Implementation of the hardware state machine so as to perform the functions described herein will be apparent to persons skilled in the relevant art(s).
[0082] In yet another embodiment, the invention is implemented using a combination of both hardware and software.
[0083] In addition, it should be understood that the figures and screen shots illustrated in the attachments, which highlight the functionality and advantages of the present invention, are presented for example purposes only. The architecture of the present invention is sufficiently flexible and configurable, such that it may be utilized (and navigated) in ways other than that shown in the accompanying figures.
[0084] Further, the purpose of the foregoing Abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The Abstract is not intended to be limiting as to the scope of the present invention in any way. It is also to be understood that the steps and processes recited in the claims need not be performed in the order presented.
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Computer-executable code is automatically generated for a message flow in a message queuing infrastructure by determining a type of the message flow, inputting message flow parameters, and generating the computer-executable code based on the type of the message flow and the message flow parameters. The generation of code can also implement a design pattern, which is input based on the determined type of message flow. The computer-executable code can be, for example, Extended Structured Query Language (ESQL) code. The type of the message flow can identify, for example, a transformation requirement of the message flow. The transformation requirement can be, for example, one of (i) transformation from a first Extensible Markup Language (XML) message to a second XML message, (ii) transformation from an XML message to a Message Repository Manager (MRM) message, and (iii) transformation from a first MRM message to a second MRM message.
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 277,516, filed Sept. 28, 1988, now abandoned, which is a continuation of application Ser. No. 168,598, filed Mar. 4, 1988, which in turn, is a continuation of Ser. No. 935,401, filed Nov. 26, 1986, now abandoned, and a continuation-in-part of copending application Ser. No. 074,978, filed July 17, 1987, now abandoned.
FIELD OF THE INVENTION
This application relates to novel bis-indole alkaloid compounds and compositions containing such compounds as active ingredients. More particularly, the invention concerns a new class of biologically active compounds which have been named topsentins, pharmaceutical compositions containing them methods of producing the compounds and methods of using them.
BACKGROUND OF THE INVENTION
Considerable research and resources have been devoted to oncology and antitumor measures including chemotherapy. While certain methods and chemical compositions have been developed which aid in inhibiting, remitting or controlling the growth of tumors, new methods and antitumor chemical compositions are needed.
The prevention and control of viral diseases is also of prime importance to man and much research has been devoted to development of antiviral measures. Certain methods and chemical compositions have been developed which aid in inhibiting, controlling or destroying viruses, but additional methods and antiviral compositions are needed.
It has been found that some natural products and organisms are potential sources for chemical molecules having useful biological activity of great diversity. Marine sponges have proved to be such a source and a number of publications have issued disclosing organic compounds derived from marine sponges including Scheuer, P. J. Ed., Marine Natural Products, Chemical and Biological Perspectives; Academic Press, New York, 1978-1983, Vol. I-V; Faulkner, D. J., Natural Products Reports 1984, 1, 551-598; 1986, 3, 1-33 & 1987, 4, 539-576; J. Am. Chem. Soc., 1985, 107, 4796-4798.
Indole compounds of marine origin have also been described in Tetrahedron Letters, 1984, 25, 5047-5048 and J. Am. Chem. Soc., 1982, 104, 3628-3635.
This present invention, utilizing sponges as a source material and supplemented by novel synthetic production methods, has provided the art with a new class of biologically active compounds and new pharmaceutical compositions useful as antitumor agents effective against specific tumors and antiviral agents.
Other advantages and further scope of applicability of the present invention will become apparent from the detailed descriptions given herein; it should be understood, however, that the detailed descriptions, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent from such descriptions.
SUMMARY OF THE INVENTION
The objects of the invention are accomplished by the provision of a novel class of biologically active compounds that have been named topsentins and have a structure according to the formula: ##STR2## R 1-8 are the same or different selected from --H, --OH, halogen, --R, --OR, --OCOR, or --OA;
Y is the single group ≠O, or two groups, same or different, selected from --H, --OH, --OR, or --OCOR with the provision that Y shall not be two --OH groups;
Z are the same or different selected from --H, or --R;
R is C1-5 alkyl and A is -R-phenyl.
A preferred group of compounds of the invention are those of the formula: ##STR3## wherein R 2 & R 6 are --H while R 3 & R 7 are --H, --OH, halogen, --R, --OR, --OCOR or --OA; or R 3 & R 7 are --H while R 2 & R 6 are --H, --OH, halogen, --R, --OR, --OCOR or --OA; Z are the same or different selected from --H, --R; R is C1-5 alkyl and A is -R-phenyl.
Particularly preferred compounds of the invention are those of the formula: ##STR4## wherein: 1: R 2 , R 3 , R 6 =H; R 7 =OH (Topsentin)
2: R 2 , R 6 =H; R 3 =Br; R 7 =OH (Bromotopsentin)
4: R 2 , R 6 , R 7 =H; R 3 =OH (Isotopsentin)
5: R 2 , R 6 =H; R 3 , R 7 =OH (Hydroxytopsentin)
60 R 2 , R 3 , R 6 , R 7 =H (Deoxytopsentin)
7: R 2 , R 3 , R 7 =H; R 6 =OH (Neotopsentin)
8: R 3 , R 6 , R 7 =H; R 2 =OH (Neoisotopsentin)
9: R 2 , R 6 =OH; R 3 , R 7 =H (Neohydroxytopsentin)
As a result of the discoveries by the invention of the new compounds as delineated above, skilled chemists will be able to use procedures as disclosed herein and others to synthesize these compounds from available stock substances. In carrying out such operations, any suitable filtration, chromatographic and other purification techniques may be utilized. Suitable chromatography techniques include reversed phase, medium pressure and high pressure liquid chromatography (RPLC, MPLC AND HPLC, respectively) with a suitable column as would be known to those skilled in the art including silica gel, Sephadex LH-20, ammonia-treated silica gel and LiChrosorb NH 2 columns. Such columns are eluted with suitable eluents such as heptane, ethyl acetate, methylene chloride, methanol, isopropyl alcohol and various combinations and ratios thereof.
As embodied and fully described herein, the invention also comprises pharmaceutical compositions, e.g., antiviral and antitumor compositions, which antitumor compositions are effective against specific tumors, containing as active ingredient an effective amount, preferably between about 0.1 to 45%, especially 1 to 25%, by weight based on the total weight of the composition, of one or more compounds according to the formulae expressed above and a non-toxic, pharmaceutically acceptable carrier or diluent.
As embodied and fully described herein, the invention also comprises processes for the production of the new compounds and compositions of the invention and methods of use thereof, e.g., methods of inhibiting certain tumors in a mammal, therapeutic methods for treating cancerous cachexia and methods of inhibiting viruses.
In accordance with the invention, methods for inhibiting certain tumors in a host comprise contacting tumor cells with an effective amount of the new pharmaceutical compositions of the invention and methods for inhibiting viruses comprise administering to the host an effective amount of the new pharmaceutical compositions of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A more complete understanding of the invention can be obtained by reference to preferred embodiments of the invention which are illustrated by the following specific examples of compounds, compositions and methods of the invention. It will be apparent to those skilled in the art that the examples involve use of materials and reagents that are commercially available from known sources, e.g., chemical supply houses, so no details are given respecting them.
One method of preparation of the new compounds of the invention involves extraction from marine sponges of the Order Halichondrida (Phylum Porifera, Class Demospongiae) which is a problematic taxonomic group, with generic distinctions not clearly defined. Four samples used in connection with this invention have been assigned to the genus Spongosorites, Topsent 1896, a genus characterized by: a distinct and thick (up to 1 mm) dermal layer of smaller spicules arranged tangentially to the surface; a confused choanosomal arrangement of spicules with sporadic vague spicule tracts running parallel to the surface; bright-yellow color when alive, turning brown or black when preserved in alcohol; and two or three size categories of straight or crooked oxea. Spongosorites sp.1 (4-XII-84-1-22, black in alcohol) has crooked oxea and is distinguished by association with vermetids (Phylum Mollusca, Class Gastropoda); Spongosorites sp.3 (4-XII-84-1-23 and 23-VIII-85-1-39, tan-brown in alcohol) has fusiform straight oxea. Voucher samples are deposited on the Indian River Coastal Zone Museum of Harbor Branch Oceanographic Institution at Ft. Pierce, Fla., and species names will be assigned when revision of the Order Halichondrida has been completed by Dr. R. Van Soest, Institute for Taxonomic Zoology, University of Amsterdam, with Dr. Shirley A. Pomponi and M. Cristina Diaz.
EXAMPLE 1
This example concerns the preparation of topsentin 1 and bromotopsentin 2.
The frozen sample (264 g) of marine sponge, Spongosorites ruetzleri, (Van Soest and Stentoft 1988), collected at a depth of 1149 feet at Goulding's Cay, Bahamas, was extracted twice with methanol-toluene (3:1). The combined extracts on concentration on a water bath at 30 C. in vacuo gave as a residue (11.32 g) of crude extract which was partitioned between pentane and 10% aqueous methanol. The alcohol layer was then diluted to 30% water and extracted with CH 2 Cl 2 . The aqueous methanol layer was concentrated and partitioned between butanol and water. A portion (200 mg) of the Herpes simplex virus type 1 (HSV-1)-active, butanol-soluble fraction was dissolved in 20% aqueous methanol (1 ml) and chromatographed on a column (ID=22 mm, height=40 mm) packed with reversed-phase material (Amicon silica--C8, 20-45 μm). The active fraction (123 mg) was eluted with 20% aqueous methanol and purified by reversed-phase HPLC (IBM 5μ, C18, 10 mm×250 mm, 20% aqueous methanol) to yield pure topsentin 1, 20 mg. and bromotopsentin 2, 67 mg as yellow powder.
Topsentin, amorphous, bright-yellow solid, mp>250° C. when analyzed by conventional methods and apparatus, produced the following spectral data:
UV absorption, λmax (MeOH) 208 nm (ε12,000), 246 sh (5100), 285 (4500) and 375 (4600);
IR (KBr) 3395, 3275, 1635, 1590, 1530, 1455, 1270, 1165, 1115, 1095, 1005 and 876 cm -1 ;
1 H NMR (360 MHz, DMSO-d 6 +1% TFA-H) 6.841 (1H, dd, J=8.6, 1.8 Hz), 6.997 (1H, d, J=1.8 Hz), 7.201 (2H, m), 7.523 (1H, d, J=7.9 Hz), 7.990 (1H, d, J=7.6 Hz), 8.041 (1H, d, J=8.6 Hz), 8.155 (1H, d, J=2.8 Hz), 8.159 (1H, s), 8.487 (1H, d, J=3.2 Hz), 11.762 (1H, s), 12.355 (1H, d, J=2.2 Hz);
13 C NMR (90 MHz, DMSO+1%TFA-H) 98.11(d), 102.72(s), 113.12(d), 113.95(s), 116.00(d), 118.67(s), 119.46(d), 120.50(d), 122.02(d), 122.44(d), 124.27(s), 125.74(d), 131.11(s), 136.53(s), 137.78(d), 138.33(s), 141.23(s), 155.25(s), 171.5(s);
EIMS 342 (100%, C 20 H 14 N 4 O 2 , M + ), 209 (39, C 12 H 7 N 2 O), 183 (28, C 11 H 9 N 3 ), 171 (17, C 10 H 7 N 2 O), 160 (145, C 9 H 6 NO 2 ), 133 (65, C 8 H 7 NO) and 105 (15).
Bromotopsentin, yellow crystals, m.p. 296°-7° C. when analyzed by conventional methods and apparatus, produced the following spectral data:
UV absorption, λmax (MeOH) 209 nm (ε13,000), 236 (9700), 287 (5000) and 374 (5800);
IR (KBr) 3400-3100, 2255, 2120, 1635, 1590, 1520, 1445, 1265, 1230, 1165, 1028, 1005 and 875 cm -1 ;
1 H NMR (360 MHz, CDCl 3 :CF 3 COOH:1:1) 7.098 (1H, dd, J=8.6, 2.4 Hz), 7.193 (1H, d, J=2.4 Hz), 7.227 (1H, dd, J=8.6, 1.8 Hz), 7.558 (1H, d, J=8.6 Hz), 7.668 (1H, d, J=1.8 Hz), 7.824 (1, s), 7.927 (1H, d, J=3 Hz), 8.202 (1H, d, J=8.6 Hz), 8.371 (1H, d, J=3 Hz), 9.272 (1h, brs), 10.409 (1H, brs);
13 C NMR (90 MHz, CDCl 3 :CF 3 COOH 1:1) 101.6(d), 103.7(s), 116.7(d), 117.0(s), 117.6(d), 118.2(d), 119.6(s), 121.5(d), 122.6(s), 125.2(s), 125.5(d), 127.7(d), 128.0(d), 135.0(s), 139.7(s), 140.5(s), 140.8(d), 141.7(s), 155.0(s), 172.4(s);
EIMS 422/420 (40%, C 20 H 13 BrN 4 O 2 , M + ), 394/392 (1.3, C 19 H 11 BrN 3 O 2 ), 342 (13, M + -Br), 289/287 (6%, C 12 H 7 BrN 3 O), 263/261 (100, C 11 H 8 BrN 3 ), 223/221 (13, C 9 H 6 BrN 2 ), 209/207 (9.5, C 9 H 6 BrNO), 182 (15, 261-Br) and 133 (94, C 8 H 7 NO).
EXAMPLE 2
This example concerns the conversion of bromotopsentin to topsentin.
Bromotopsentin in absolute ethanol was stirred vigorously with 10% palladium on activated carbon under hydrogen at room temperature for 4 hrs. The reaction mixture was filtered and washings were evaporated in vacuo to give a quantitative yield of topsentin identical to natural topsentin in LREIMS and 1 H NMR spectra.
EXAMPLE 3
Frozen sponge sample of Spongosorites sp.3 collected at Goulding's Cay, Bahamas at --229 m was homogenized and steeped repeatedly in methanol and 10% toluene followed by methanol. The alcohol layer was concentrated and re-partitioned between 1-butanol and water, and the butanol-soluble fraction was vacuum chromatographed over RP material (Amicon, silica gel C18, 20-45 μm) using 20% aqueous methanol. The yellow fraction was then subjected twice to RP-HPLC (C18, 5 μm, 20% water in MeOH) to give bromotopsentin 2 and 4,5-dihydro-6"-deoxybromotopsentin 3 of the formula: ##STR5##
Compound 3 is a yellow powder with the following spectral data:
[α] 24 D 198° (c 2.0, MeOH).
UV (MeOH) λmax nm 328 (ε5700), 274 (8800), 214 (34,000), 198 (29,500);
IR (KBr) 3620, 3390, 3280, 2920, 2860, 1665, 1570, 1450, 1420, 1332, 1240, 1160, 1120, 1100, 1020, 950, 805 and 750 cm -1 ;
LREIMS m/z (rel intensity) 406(95), 404(100), 378(41), 376(39), 326(10), 298(6), 297(7), 291(10), 289(9), 235(6), 233(6), 210(12), 208(10), 197(10), 195(10), 189(5), 156(12), 155(19), 144(28), 130(14).
1 H and 13 C NMR collected data also supported the structure given above.
Calcd for C 20 H 13 79 BrN 4 O: 404.0272 (M-2H). Found 404.0300 (HREIMS).
EXAMPLE 4
This example concerns the preparation of 3-(hydroxyacetyl)indole 12 as a synthon.
3-(Chloroacetyl)indole was prepared in 34% yield according to a known procedure (Bergman, J. Heterocycl. Chem. 1970, 7, 1071-1076) and characterized by spectral data. The product was added to formamide-water (10:1) and stirred at 110 C. for 3.5 hrs. The reaction mixture was treated with a large excess of 14% aqueous ammonia and extracted with chloroform. After evaporation, the crude product (65 mg) was purified by RP(MP)LC (Waters C18; MeOH:H 2 O:3:1) to give 12 in 97% yield as colorless needles, mp 173-174 C.
Calcd for C 10 H 9 NO 2 : 175.0633. Found: 175.0633 (HREIMS).
EXAMPLE 5
This example concerns the preparation of 3-chloroacetyl-6-(benzyloxy)indole 11 as a synthon.
6-(Benzyloxy)indole dissolved in a mixture of dioxane and pyridine was stirred at 60 C. under nitrogen while chloroacetyl chloride in dioxane was added dropwise during 1 hr. The reaction mixture was then stirred for another 0.5 hr. and poured into diethyl ether-water. The precipitate was collected by filtration and washed thoroughly with cold diethyl ether to yield 47% of 11 as an orange solid.
Calcd for C 17 H 14 35 ClNO 2 : 299.0713 Found: 299.0713 (HREIMS).
EXAMPLE 6
This example concerns the preparation of 3-hydroxyacetyl-6-(benzyloxy)indole 13 as a synthon.
A solution of 11 in dioxane was added to formamide-water (10:1). The mixture was stirred at 110° C. for 10 hrs., then worked up and purified as described above to yield 82% of 13 as colorless prisms with mp 194°-195° C. (EtOAc).
Calcd for C 17 H 15 NO 3 : 281.1052. Found: 281.1047 (HREIMS).
EXAMPLE 7
This example concerns the synthesis directly from (hydroxylacetyl)indoles of O-benzyltopsentin 16, O-benzylisotopsentin 17, O,O'-dibenzylhydroxytopsentin 18, and deoxytopsentin 6.
Copper(II) acetate monohydrate (506 mg) in 30% aqueous ammonia (10 ml) was added dropwise to a refluxing, stirred mixture of 3-(hydroxyacetyl)indole 12 (136 mg) and 3-hydroxyacetyl-6-(benzyloxy)indole 13 in ethanol (20 ml) during 5 min. After addition was completed, the reaction mixture refluxed for another 10 min., then was allowed to cool to room temperature. Hydrogen sulfide gas was bubbled through the solution for 5 min. Filtration and evaporation gave a brown solid. Column chromatography (SiO 2 , 20 g; CHCl 3 :MeOH:50:1) followed by RP-MPLC (Waters C18, 50 g; MeOH:H 2 O:3:1-4:1) and HPLC (Alltech C18, MeOH:H 2 O:7:3) gave 16, 17, 18 and 6 with recovered 12 and 13.
EXAMPLE 8
This example concerns the preparation of 6 & 16-18 from isolated glyoxalkyl intermediates.
Copper(II) acetate monohydrate in 50% aqueous acetic acid was added to 12 in ethanol. The mixture refluxed with stirring for 4 hrs., then was allowed to cool to room temperature, filtered through "Celite" and evaporated at reduced pressure. Water was added and the aqueous layer was extracted with ethyl acetate. The combined organic phase was washed with water, saturated with aqueous NaHCO 3 and brine. It was then evaporated in vacuo to give nearly pure 3-glyoxalylindole 14.
Similarly, 13 in ethanol was treated with copper(II) acetate monohydrate in 50% aqueous acetic acid. Work-up gave nearly pure 3-glyoxalkyl-6-(benzyloxy)indole 15.
14 and 15, both prepared as above, were dissolved in 75% aqueous EtOH. Ammonia gas was bubbled through the solution for 15 min. at room temperature, then for another 15 min. under reflux. After cooling, the solvent was removed in vacuo, and the residue was purified by column chromatography (SiO 2 , CHCl 3 :MeOH:50:1) followed by RP-MPLC (Waters C18, MeOH:H 2 O 1:1-3:1) and HPLC (Merck LiChrosorb NH 2 , 7 μm; CHCl 3 :MeOH:10:1) to obtain 16, 17, 18 and 6.
O-Benzyltopsentin 16 is a bright yellow solid whose structure was established by spectral analysis.
Calcd for C 27 H 20 N 4 O 2 : 432.1586 Found: 432.1594 (HREIMS).
O-Benzylisotopsentin 17 is a bright yellow solid whose structure was established by spectral analysis. Calcd for C 27 H 20 N 4 O 2 : 432.1586 Found: 432.1594 (HREIMS). O,O'-Dibenzylhydroxytopsentin 18 is a bright yellow solid, mp>250° C., whose structure was established by spectral analysis. Calcd for C 34 H 26 N 4 O 3 : 538.2005 Found: 538.2003 (HREIMS).
Deoxytopsentin 6 is a bright yellow solid, mp>250 C., whose structure was established by spectral analysis.
EXAMPLE 9
This example concerns the conversion of O-benzyltopsentin to topsentin.
A solution of 16 in absolute EtOH was stirred vigorously with 10% palladium on activated carbon under hydrogen at room temperature for 10 hr. The reaction mixture was filtered through "Celite" and washed thoroughly with EtOH. After evaporation of EtOH, topsentin was obtained in quantitative yield. The synthesized topsentin was identical with natural topsentin in spectral data and in biological activities.
EXAMPLE 10
This example concerns the conversion of O-benzylisotopsentin 17 to isotopsentin 4.
A solution of 17 in absolute EtOH was treated with 10% palladium on activated carbon as for 16 in Example 9 to give 4 in quantitative yield, a yellow, amorphous solid whose structure was established by spectral data.
EXAMPLE 11
This example concerns the synthesis of hydroxytopsentin 5 from 3-hydroxyacetyl-6-(benzyloxy)-indole 13.
Ammonia gas was bubbled for 15 min. through a solution of 15, prepared as in Example 8 from 13, in 75% aqueous EtOH, then the mixture refluxed for another 15 min. The precipitate was collected by filtration and washed with methanol to yield 18. The combined filtrate and washings were purified by column chromatography to give an additional amount of 18 (total yield 63% from 13).
The precipitate of 18 was dissolved in methanol and the solution was stirred vigorously with 10% palladium on activated carbon under hydrogen at room temperature for 2 hrs. Work-up as described for the synthesis of 1 and 4, followed by RP-MPLC purification gave 5 (89%), a yellow solid whose structure was established by spectral data. Calcd for C 20 H 14 N 4 O 3 : 358.1066 Found: 358.1074 (HREIMS).
EXAMPLE 12
This example concerns the preparation of 3-chloroacetyl-5-(benzyloxy)indole 19.
5-(Benzyloxy)indole in dioxane containing pyridine was stirred for 1 hr. at 65° C. under nitrogen while chloroacetyl chloride in dioxane was added dropwise. The reaction mixture was stirred for another 1 hr., then poured into diethyl ether-water. The precipitate was collected by filtration and washed thoroughly with cold Et 2 O to yield 19, an orange solid.
Calcd for C 17 H 14 35 ClNO 2 : 299.0713 Found: 299.0715 (HREIMS).
EXAMPLE 13
This example concerns the preparation of 3-hydroxyacetyl-5-(benzyloxy)indole 20.
A solution of 19 in dioxane was added to formamide-water (10:1) and the mixture was stirred at 110° C. for 6.5 hrs., then was worked up as for 12 above. Purification by column chromatography gave 20 (55%) whose structure was established by spectral data. Calcd for C 17 H 15 NO 3 : 281.1052 Found: 281.1052 (HREIMS).
EXAMPLE 14
This example concerns the synthesis of neohydroxytopsentin 9.
A solution of 20 in ethanol was treated with copper(II) acetate monohydrate in 50% aqueous acetic acid as described above for 15. Work-up gave nearly pure 3-glyoxalyl-5-(benzyloxy)indole 21.
Ammonia gas was bubbled for 15 min. through a solution of 21 in 75% aqueous EtOH and the mixture refluxed for another 15 min. After evaporation, the crude product was purified by column chromatography to give O,O'-dibenzylneohydroxytopsentin 24 (60%), a yellow amorphous solid whose structure was established by spectral data.
A solution of 24 in MeOH was stirred vigorously with 10% palladium on activated carbon under hydrogen at room temperature for 3 hrs. Work-up in the usual manner gave a crude product which was purified by HPLC to give 9, a bright-yellow, amorphous solid whose structure was established by spectral data.
Calcd for C 20 H 14 N 4 O 3 : 358.1031 Found: 358.1031 (HREIMS).
EXAMPLE 15
This example concerns the synthesis of neotopsentin 7 and neoisotopsentin 8.
Ammonia gas was bubbled through a solution of 14 (prepared from 12) and 21 (prepared from 20) in 75% aqueous EtOH, then for another 15 min. under reflux. After cooling, the solvent was removed in vacuo and the residue was purified by column chromatography followed by RP-MPLC, then by HPLC to obtain benzylneotopsentin (11%), benzylisotopsentin 23 (9%), dibenzylneohydroxytopsentin 24 (3%) and 6 (28%).
Compound 22 in MeOH was stirred vigorously with 10% palladium on activated carbon under hydrogen at room temperature for 3 hrs. The reaction mixture was filtered through "Celite" and washed thoroughly with EtOH. Evaporation of EtOH gave 7 (90%), a bright yellow, amorphous solid whose structure was established by spectral data. Found for C 20 H 14 N 4 O 2 : 342.1118 (HREIMS).
Compound 24 in MeOH was treated with 10% palladium on activated carbon under hydrogen at room temperature for 3 hrs and worked up as for 7 above to give 8 (86%), a bright yellow, amorphous solid whose structure was established by spectral data. Found for C 20 H 14 N 4 O 2 : 342.1114 (HREIMS).
ANTITUMOR ACTIVITIES OF THE NEW COMPOUNDS
The following assay method was utilized to illustrate the antitumor effectiveness of the compounds of the invention.
P388 IN VITRO ANTITUMOR SCREEN
Cell Culture. P388 murine leukemia cells, obtained from the National Cancer Institute, Bethesda, MD, were maintained at 37° C. in 5% CO 2 in humidified air. Growth medium was Roswell Park Memorial Institute medium 1640 supplemented with 10% heat-inactivated horse serum. Stock cultures of P388 cells were grown in antibiotic-free growth medium and were subcultured (10 5 cells/ml, 25 ml cultures in T-25 plastic tissue culture flasks) every 2-3 days. Every 3-4 months, stock cultures were reinitiated from frozen cells that were demonstrated to be free of mycoplasma contamination. To determine if organisms possess compounds having activity against P388 cells, extracts were diluted in methanol and added to cultures of P388 cells. An appropriate volume of the dilution was transferred to duplicate wells in a 96-well plate, evaporated to dryness, and 200 μl of growth medium containing cells at a density of 1×10 5 cells/ml was added per well. (Final concentration of extract was 20 μg/ml.) Each plate included six wells containing untreated cells for control growth (mean generation time was 15.2±0.7 hr, n=26 separate determinations) and replicate wells containing fluorouracil (0.2 μg/ml, ca. 95% inhibition of cell replication) as a positive control. For daily quality control, each technician determines the IC 50 of fluorouracil for inhibition of P388 cell proliferation. After 48-hour incubations, cell number was determined with the MTT assay (below), calculated as a percent of untreated cell growth, converted to percent inhibition, and reported to the chemist requesting the screen.
Determination of IC 50 Values. The initial determination of an IC 50 value for inhibition of P388 cell proliferation with a crude, semipure, or pure sample was made by diluting the sample in methanol to the appropriate concentration and then serial 1:1 dilutions were made in duplicate in a 96-well plate, such that the final concentrations in the assay were 20, 10, 5, 1.25, and 0.625 μg/ml. After solvent was evaporated to dryness, cells were added to each well as described above. After 48-hour incubations, cell numbers were determined with the MTT assay, converted to percent control, plotted versus the log of the sample concentration. Curves were fitted by least-squares linear regression of logit-transformed data and the concentration of sample that inhibited cell proliferation by 50% was reported to the chemist requesting the screen. If the IC 50 value was less than 0.625 μg/ml, additional serial dilutions were made and tested for activity.
MTT Assay for Cell Number. MTT or 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide is used in an established method (J. Immunol. Methods, 1983, 65: 55-63) to enumerate cells rather than "Coulter counting". For screening purposes, the correlation between percent inhibition determined for actual crude extracts with the Coulter counter and MTT method was very good (r=o.953, n=102 separate determinations of activity at 20 μg/ml), and no extract that was positive as determined by actual cell counts was lost using the MTT assay. Additional results indicated that the MTT assay yielded very similar values for IC 50 's in parallel determinations with Coulter counting.
HUMAN TUMOR CELL LINE ASSAY
Maintenance of Cell Line
HCT-8 human colon tumor cells are grown in RPM1 1640 medium (GIBCO). A549 human lung carcinoma cells and T47D human breast carcinoma cells are cultured in Dulbecco medium (Biologos, Inc.). All media are supplemented with 10% fetal bovine serum and contain 50 μg/ml gentamicin. All human tumor cell lines are incubated in 5% CO 2 at 37° C. and subcultured once a week.
Procedure
1. Seed 1 ml of cells (5000 HCT-8, 8000 A549, 12000 T47D) into each well of a 24-well plate.
2. Incubate in a CO 2 -incubator for 48 hours.
3. Add compound to each well and incubate for an additional 120 hours.
4. Discard medium and stain with methylene blue (HCT-8) or crystal violet (A549 & T47D).
5. Compare density of drug-treated well with that of the control (no drug added) as follows: ND (not detectable) >90%, 1+=75-90%, 2+=50-74%, 3+=25-49%, 4+=<25% of control growth.
Final conc. of Vinblastine or Vincristine control (use 2 μl/assay).
______________________________________Solution conc Amt. added Final conc. in test______________________________________50 mg/ml 2 μ1 50 μg/ml20 mg/ml 2 μ1 20 μg/ml5.0 mg/ml 2 μ1 5.0 μg/ml0.5 mg/ml 2 μ1 0.5 μg/ml______________________________________
For solvents other than water, allow solvent to evaporate from tube or well in hood. Always run a solvent control in duplicate in the last two wells of each plate or four tubes for each rack of 72 or fewer tubes. Also run four wells or tubes with media and cells only per run of plates or tubes. When using volumes of aqueous solutions greater than 200 ml, dry sample and bring to desired concentration in media.
Results of the in vitro antitumor assay of compounds 1-9 are summarized in Table 1.
TABLE 1__________________________________________________________________________COMPOUNDSASSAY 1 2 3 4 5 6 7 8 9__________________________________________________________________________P388 IC.sub.50 : 2.0 7.0 4.0 4.0 0.3 12.0 2.5 1.8 >20(ug/ml)HCT-8:50 pg/ml 4+ 4+20 pg/ml 4+ 4+ NT NT NT NT NT NT NT5 pg/ml 1+ ND.sup.b0.5 pg/ml ND NDA549:50 pg/ml 4+ 4+20 pg/ml 4+ 4+ NT NT NT NT NT NT NT5 pg/ml ND ND0.5 pg/ml ND NDT47D:50 pg/ml 4+ 4+20 pg/ml 4+ 3+ NT NT NT NT NT NT NT5 pg/ml 2+ 2+0.5 pg/ml ND ND__________________________________________________________________________ .sup.a NT = not tested .sup.b ND = not detected
Table 1 shows that topsentin class compounds 1-8 have good antitumor activity at concentrations of 20 μg/ml or less.
Procedure for P388 In-Vivo Assays
P388 leukemia obtained from DBA/2 mice was inoculated ip into BDF1 mice. The inoculum level was 10 6 cells in 0.1 ml. Mice were randomized on day 1 into groups of six mice since bacteriological check of tumor was negative. Test materials were dissolved or suspended in sterile 0.98% NaCl solution with the aid of absolute ethanol and "Tween-80", then administered ip, qD1-5, in a volume of 0.5 ml/mouse. Mice were weighed on days 1 & 5 to provide evidence of toxicity and deaths were recorded daily. Each test included appropriate numbers of untested control mice, one-dose level of the positive reference compound 5-fluorouracil and test material (four dose levels each). Test material were prepared fresh on day 1 and administered daily for five days. Quantity and consistency of test material precluded fresh preparation daily. Doses were derived from prior single treatment acute toxicity assays. The endpoints for therapeutic evaluation were mean and median survival time and long-term survivors on day 30. A 25% percent increase in life span (%ILS) was considered evidence of significant activity.
Table 2 reports the in vivo antitumor assay results for compounds 1 & 2.
TABLE 2______________________________________Dose mg/kg Treatment (days) Survival % T/C______________________________________Compound 1300 1- 5 110150 1-5 13275 1-5 11637.5 1-5 111Compound 2300 1-4 toxic150 1-5 11675 1-5 11137.5 1-5 105______________________________________
It is apparent from the in vitro and in vivo testing and results reported in Tables 1 & 2 that the compounds of the invention are effective for inhibiting or destroying certain tumors and therefore in controlling diseases caused by or related to such tumors, e.g., cancerous cachexia.
Antiviral Activities of Compounds of the Invention
The following assay methods were utilized to evaluate the in vitro activity of compounds of the invention.
ANTIVIRAL DISC ASSAY FOR HSV-1
A. Maintenance of Cell Cultures
1. Virus
a. Herpes simplex type 1 (HSV-1) replicates in the CV-1 cell line. CV-1 is a fibroblast-like cell culture derived from primary African green monkey cells.
2. Growth of CV-1 Cells
a. Seed 150 cm 2 tissue culture flasks each with 10×10 6 CV-1 cells in 40 ml of EMEM with 10% FBS (growth medium).
b. Seven days after seeding the flasks, cell numbers should be approximately 40-50×10 6 . CV-1 cells have a doubling time of 72 hours based on these numbers.
3. Trypsinization
a. Aseptically remove the medium
b. Rinse cell sheet two times with 10 ml of Ca ++ - and Mg ++ -free Dulbecco's phosphate buffered saline.
c. Add 1.5 to 2.0 ml of trypsin-EDTA mixture.
d. Incubate flask at room temperature for 10 minutes.
e. Shake flask.
f. Add 10 ml EMEM growth medium and break up cell clumps with pipetting.
g. Count cells.
B. Preparation of plates for viral assays
Cell Concentration
a. Dilute the cells with EMEM to 4×10 5 cells/ml.
b. See 24-well trays with 0.5 ml per well. Cell concentration is 2×10 cells.
c. Incubate at 37 C. for 1.5 hours.
d. The wells can be used over the next several days beginning the day after seeding (preferably 2, 3, or 4).
C. Assay of HSV-1 in CV-cells
Infection of CV-1 cells in plates with virus
a. Remove medium from wells.
b. Infect well with at least 25 and no more than 80 plaque forming units (PFU) of virus.
c. Incubate infected cells at 37 C. for 1.5 hrs.
d. Pour off supernatant at end of incubation period.
e. Add 0.5 ml of methylcellulose overlay medium (MCO). MCO is a maintenance medium without phenol red made with 1% 4000 centipose methylcellulose. FBS is used at 5% level.
Drug Evaluation
a. For drug evaluation wet filter paper discs (6 mm dia.) with approx. 0.02 ml of test compound. Allow solvent to evaporate for 20-30 mins. at ambient temperature, then place discs in the well containing CV-1 cells, virus and MCO.
b. Incubate tissue culture plates for 48 hrs. at 37 C.
c. After 48 hrs. place 0.5 ml NRMCO on each well. (NRMCO is a maintenance overlay medium without phenol red containing 0.1 mg neutral red dye/ml and 2% 15 Cps. methylcellulose.
d. Incubate plates at 37 C. and read the following day. Antiviral activity should be observed from two parameters. One is actual reduction in the number of plaques and two is the diminution in plaque diameter.
Scoring Drug Activity
a. Antiviral activity (AVA) is scored from 0 to +++.
+++=complete inhibiton of plaque formation
++=partial inhibition
+=partial inhibition
0=no protection
b. Cytotoxicity (Cyt)
0=no visual or microscopic cytotoxicity
16=complete cell destruction
8, 10, 12, 14=partial cytotoxicity.
Antiviral Assay for Mouse Coronavirus Strain A59
When NCTC 1469 cells (a clone of mouse liver cells) are infected with mouse coronavirus A59, the cytopathic effects (CPE) which result are characterized by giant cell formation, cell fusion, and cell destruction. Cell fusion observed in NCTC 1469 cell cultures infected with strain A59 can be observed microscopically in 12 hours and when stained with methylene blue dye the syncytia are visible to the eye as dark blue foci on the fixed cell sheet. Twenty-four hours after infection cell fusion and cytopathic effects are extensive and the assays can be read both macroscopically and microscopically. Compounds with antiviral activity can be identified by comparing the CPE in drug treated cultures to that observed in untreated infected cells.
Assay Protocol
1. Cells
NCTC clone 1469, a derivative of mouse liver, ATCC No. CCL 9.
2. Virus
Mouse hepatitis virus strain MHV-A59 classified as a corona virus, ATCC No. 764
3. Media
Growth medium
NCTC 135
10% horse serum,
2% 1-glutamine (200 mM)
1% nonessential amino acids (NEAA) (100×)
1% sodium pyruvate (110 mg/liter) (100×)
50 μg/ml gentamicin
Maintenance medium
Dulbecco's modified Eagle's minimum essential medium in Earle's balanced salt solution (4500 mg/liter glucose) (D-EMEM)
5% fetal bovine serum
2% 1-glutamine (200 mM)
1% nonessential amino acid (NEAA) (100×)
1% sodium pyruvate (110 mg/liter) (100×)
50 μg/ml gentamicin
Trypsin solution
0.5 mg/ml trypsin, 0.2 mg/ml EDTA.4Na, and 1.1 mg/ml glucose in Dulbecco's phosphate buffered saline without CaCl 2 and MgCl.6H 2 O
(PBS)
Methylene blue stain
5 grams methylene blue/liter
50% ethanol:water
4. Growth of NCTC 1469 cell line
Confluent cultures are exposed briefly to the trypsin solution and flasks are shaken hard to remove cells from the plastic. For a 150 ml flask add 4 ml of trypsin solution and reduce volume for smaller cell areas. Subcultures for cell maintenance are seeded at 10×10 6 cells in 40 ml growth medium for 150 ml tissue culture flask. Cells are subcultured twice a week.
5. Antiviral assay
Plates (24 well, 16 mm diameter/well) are seeded with between 7.5×10 5 and 1×10 6 cells in 1 ml growth medium per well. Plates are incubated 24 hours at 37 C. in 5% CO 2 . The growth medium is removed and the cultures are infected with 0.2 ml A59 diluted in PBS with calcium and magnesium to contain approximately 100 infectious doses of virus. Plates are incubated at 37 C. for 1 hour in 5% CO 2 . Viral supernatants are removed and replaced with maintenance medium only or medium containing drug solutions. The drug solutions are prepared by adding diluted samples to glass tubes and allowing solvents to evaporate. Ten lambda of dimethyl sulfoxide is added to each tube to solubilize drug material and 1 ml maintenance medium is added to the tube. The fluid from each tube is transferred to the NCTC 1469 cells infected with A59 virus.
Cytopathic effects can be observed in 12 hours. Plates are routinely read at 24 hours after fixation and staining with methylene blue dye.
Drug cytotoxicity
Cell viability is used to determine drug cytotoxicity.
100%=complete cell destruction
75%=partial cell destruction
50%=partial cell destruction
25%=partial cell destruction
0%=no cytotoxicity
Antiviral activity
+++=absence of CPE and cell fusion
++=partial inhibition
+=partial inhibition
±=marginal inhibition
0=no protection
The fifty percent minimum inhibitory concentration (MIC 50 ) is determined by estimating the percent reduction in CPE compared to the controls from the inhibition values with +++=100% reduction, ++=75%, +=50%, ±=25%, and -=no reduction in plaque number compared to controls.
The results of the HSV-1 antiviral activity assays on compounds 1, 2, 5, 7, 8 & 9 are reported in Table 3.
TABLE 3______________________________________COMPOUND DOSE (ug/disk) CYT. AVA______________________________________1 200 0 ++ 50 0 + 20 0 -2 200 0 ++ 50 0 -5 20 0 -7 20 0 -8 20 0 -9 20 0 -______________________________________
The results of the HSV-1 antiviral activity assays on compounds 1-9 are reported in Table 4.
TABLE 4______________________________________COMPOUND DOSE (μg/disk) CYT. AVA______________________________________1 20 0 +++ 2 0 +++ 0.2 0 -2 10 0 ++ 5 0 -3 20 0 +++ 2 0 -4 20 0 +++ 2 0 -5 20 0 ++ 2 0 -6 20 0 +++ 2 0 ++7 20 0 -8 20 0 -9 20 0 -______________________________________
It is apparent from the in vitro testing that the compounds of the invention are effective for inhibiting viral growth and for controlling virus related diseases such as Herpes and the common cold.
Therapeutic application of the new compounds and compositions containing them can be contemplated to be accomplished by any suitable therapeutic method and technique presently or prospectively known to those skilled in the art. Further, the compounds of the invention have use as starting materials or intermediates for the preparation of other useful compounds and compositions.
In accordance with the invention, pharmaceutical compositions comprising, as active ingredient, an effective amount of one or more of the new compounds and one or more non-toxic, pharmaceutically acceptable carriers or diluents. Examples of such carriers for use in the invention include ethanol, dimethyl sulfoxide, glycerol, silica, alumina, starch and equivalent carrier and diluents. While effective amounts may vary, as conditions in which such compositions are used vary, a minimal dosage required for antitumor activity is generally between 0.01 and 100 micrograms of the new compound against 10 5 tumor cells and a minimal dosage required for antiviral activity is generally between 50 and 200 micrograms against 25-80 plaque-forming units of virus. To provide for the administration of such dosages for the desired therapeutic treatment, new pharmaceutical compositions of the invention will advantageously comprise between about 0.1% and 45%, and especially, 1 and 15%, by weight of the total of one or more of the new compounds based on the weight of the total composition including carrier or diluent.
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A new class of novel, biologically active bisindole alkaloid compounds, which have been named topsentins, pharmaceutical compositions containing them, methods of producing the compounds and methods of using them are disclosed. This new class of compounds has the generic formula: ##STR1## R 1-8 are the same or different selected from --H, --OH, halogen, --R, --OR, --OCOR, or --OA;
Y is the single group --O, or two groups, same or different, selected from --H, --OH, --OR, or --OCOR with the provision that Y shall not be two --OH groups;
Z are the same or different selected from --H, --R;
R is C1-5 alkyl and A is --R--phenyl.
The compounds are antiviral agents and antitumor agents which are effective against specific tumors.
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FIELD OF THE INVENTION
[0001] The present invention relates to mousetraps for trapping and/or killing mice, in particular, domestic mice.
BACKGROUND OF THE INVENTION
[0002] Mice, although small, can still cause much damage. They destroy articles such as food, books, furniture and even appliances with their gnawing, urine and faeces. Another undesirable trait associated with mice, particularly in domestic environments, is their association with a variety of human diseases, such as for example, asthma. Mice can also spread a variety of organisms that can cause diseases of humans and pets. These include a variety of food poisoning bacteria like Salmonella, Shigella, Escherichia coli ( E. coli ), and others. While the risk of mouse invasion is able to be somewhat controlled or minimised by preventing food waste such as crumbs accumulating in the home, or ensuring that stored food is isolated from the external environment in, for example, sealed containers, it is not always possible to ensure that no food will be left exposed for a period of time. Also, minimising the risk of mice invasion by sealing of cracks, spaces and openings such as vents, pipes and chimney access points can be an expensive, labour intensive and time consuming exercise and is not always possible.
[0003] Traditional methods of dealing with mouse invasion in the home involves the use of poisoned baits (rodenticides) that contain anticoagulants, such as warfarin, pival and chlorophacinone. Such baits, while effective, are nevertheless toxic and are therefore undesirable for use in the home, particularly those in which children and pets reside. In addition, poisoned mice often die in inaccessible locations thereby resulting in an unpleasant odor upon death of the mouse. To circumvent these problems, mousetraps are often employed instead of poisoned baits. Traps are generally preferred as these are less hazardous to use around children and pets. Because mice are caught by the trap, there is less chance of odor from mice dying in wall voids or other inaccessible areas. Mousetraps in the form of wooden-based snap traps are common. While these traps are generally effective, they have the problem of exposing the homeowner, for example, to the highly undesirable task of disposing of the dead mouse once trapped. In addition, once trapped, the exposed dead mouse can pose health problems or cause distress to, for example, children. Furthermore, such traps are also pose a danger to children and pets who may inadvertently activate the trigger and injure themselves. Whilst mousetraps have been developed in which a trap is located within an enclosure in an attempt to isolate the trap from the outside environment and somewhat conceal the dead mouse from view, the enclosure of such mousetraps are not self-sealing after trapping and therefore the home-owner is still exposed to the dead mouse when disposing of the mouse and/or the trap.
[0004] While recognising the shortcomings of prior art mousetraps, the present inventors have sought to overcome these deficiencies with a mousetrap that substantially isolates the trap mechanism and a trapped mouse from the external environment. Such traps are desirably simple and cost effective to manufacture and are also able to efficiently trap mice.
SUMMARY OF THE INVENTION
[0005] The present invention provides a mousetrap comprising an enclosure comprised of at least a top, a base and a closable aperture; and a trigger mechanism comprising a lever arrangement connected to a biasing means, wherein the aperture, when open, is adapted to admit the mouse into the enclosure and when closed, the trapped mouse is substantially concealed within the enclosure, the mousetrap being set to trap the mouse by manual rotation of the top relative to the base to open the aperture which is held open against the force of the biasing means by engagement of the lever arrangement with a stop means, the mousetrap being activated to trap the mouse by the entry of the mouse into the enclosure causing the lever arrangement to disengage from the stop means thereby causing the top to contra-rotate relative to the base under the force of the biasing means so as to close the aperture, thereby trapping the mouse and substantially concealing the trapped mouse within the enclosure. As such, a mousetrap is provided that is self-closing following the trapping of a mouse. This self-closing feature is particularly desirable as this removes the exposure of the user, for example the homeowner, to the trapped mouse or the need for the user to close the mousetrap once a mouse has been trapped. The mousetrap according to this preferred embodiment is also advantageous as the user is able to readily determine when a mouse has been trapped without the need of actually observing the trapped mouse. A further associated advantage with the mousetraps according to the present invention is increased safety; that is, the enclosure surrounding the trap mechanism prevents, for example, a child or pet from inadvertently setting off the trap and causing possible injury, and also, children and pets are not exposed to trapped or dead mice that can be possible sources of disease.
[0006] Preferably, the mousetrap in accordance with a preferred embodiment of the invention further comprises a strike plate connected to the top that extends substantially at right angles to an internal wall of the enclosure such that upon rotation of the top relative to the base under the action of the biasing means, the strike plate rotates with the top and contacts the mouse. In this way, the mouse is contacted by the strike plate thereby incapacitating or killing the mouse. Preferably also, the mousetrap further comprises a catch plate connected to the base and extending substantially at right angles to an internal wall of the enclosure such that upon contra-rotation of the top relative to the base under the action of the biasing means, the strike plate rotates with the top and contacts the mouse to trap the mouse between the strike plate and the catch plate. As such, not only is the mouse struck by the strike plate upon contra-rotation of the top relative to the base, but it is subsequently squashed between the strike plate and the catch plate thereby increasing the effectiveness of the mousetrap to trap, incapacitate or kill the mouse. In a particularly preferred embodiment of the invention, the stop means may also serve as the strike plate, the strike plate being connected to the top and extending substantially at right angles to an internal wall of the enclosure such that upon contra-rotation of the top relative to the base under the action of the biasing means, the strike plate rotates with the top and contacts the mouse.
[0007] The mousetrap according to a preferred embodiment of the invention preferably has at least a section of the base and top that is circular. Such sections thereby allow the top and base to rotate relative to each other. For instance, the outer surface of the top and base may be, for example, square or hexagonal in shape, but each of the top and base still having a circular portion so as to be able to be interfitted in such as way as to allow the top and base to rotate relative to one another. In a particularly preferred embodiment of the invention however, the enclosure is circular in shape.
[0008] It is envisaged that the mousetrap in accordance with the present invention may be a single-use device (i.e disposable) wherein a user disposes of the mousetrap and the trapped mouse without the need to open the mousetrap and remove the mouse. The mousetrap in accordance with a preferred embodiment of the invention may, however, be reusable such that a user is able to remove and reset the mousetrap. In this regard, so as to assist in the removal of the dead mouse, the mousetrap is able to be disassembled. This feature also advantageously assists in the cleaning of the mousetrap after removal of a dead mouse prior to resetting the mousetrap.
[0009] In a particularly preferred embodiment, the biasing means is a helical torsion spring. Alternative biasing means such as elastic materials, spring metals in leaf or flat spring form, or compression springs or any other biasing means known to persons skilled in the art.
[0010] So as to assist in the incapacitation or killing of mice, the mousetrap according to a preferred embodiment of the invention also includes one or more spikes extending from the strike plate thereby impaling the mouse upon contact. Alternatively, the strike plate and/or catch plate may further include one or more projections that assist in striking and kill of the mouse. In a particularly preferred embodiment, the projections are in the form of angular kinks in the strike and/or catch plate profiles.
[0011] It is envisaged that the mousetrap according to yet another preferred embodiment will further comprise a bait housing. Preferably, the bait housing is located in the centre of the enclosure. In this way, the mouse has to enter the maximum distance into the mousetrap enclosure before activating the trap. This ensures that the mouse is fully enclosed within the enclosure before trap occurs, thereby substantially concealing all parts of the trapped mouse from external view. Preferably also, the bait housing is able to be loaded with bait from the underside of the enclosure base. This makes the mousetrap easy and efficient to load with bait without the need for disassembly of the mousetrap. Once the bait is positioned, through the underside of the mousetrap, in place, the bait may be retained in position with a seal, such as, for example, an adhesive label that is able to be peeled back to insert the bait into the bait housing and subsequently adhered to maintain the bait in position. Preferably also, the bait housing is configured so that the bait is physically isolated from the enclosure wherein the bait housing comprises one or more vents to allow the bait to be sensed by the mouse. The bait housing may still further include one or more spikes that assist in maintaining the bait within the bait housing. Also envisaged is the mousetrap may be provided to the consumer with bait located within the bait housing. In this way, baits such as grains, nuts or seeds presented as whole or broken pieces, or as the base for paste, gel, pellet, or extruded or moulded wax-block formulations with or without additional pheromone or animal- or plant-derived ingredients, are able to stored long-term within the mousetrap and sold as a single unit to the consumer.
[0012] In a particularly preferred embodiment, the mousetrap according to a preferred embodiment of the invention further includes a lip adapted to fit around the top of another mousetrap thereby allowing two or more mousetraps to be stacked. This is particularly advantageous when the mousetraps are displayed for sale in multiple units per pack.
[0013] The present invention also provides a mousetrap comprising an enclosure having an aperture through which a mouse enters and an enclosure floor; the mousetrap further comprising a trap mechanism disposed within the enclosure; the trap mechanism comprising at least a biasing means, a trigger and a trap wire with the trap wire being connected to the biasing means and arranged so as to allow the trap wire to be set through engagement with the trigger, to a first position against the force of the biasing means in which the mousetrap is set to trap a mouse; the trap mechanism being arranged such that entry of the mouse into the enclosure and depression of the trigger by the mouse causes the trigger to disengage from the trap wire which, through the force of the biasing means, is caused to move from the first position to a second position thereby trapping the mouse between the trap wire and floor, wherein the trigger and opening are arranged so as to substantially conceal and isolate the trapped mouse from the external environment. Preferably the trap mechanism further comprises a trap base. More preferably, the trap base is a wire support base. In a particularly preferred embodiment of the invention, the trap base is formed from a substantially rigid material. Suitable materials are injection mouldable materials such as plastic material polyethylene, polypropylene, ABS, and polystyrene. In this way, when a relatively bendable enclosure such as, for example, an enclosure fabricated from cardboard is used, the unit is able to withstand higher stress loads on the enclosure without compromising the operation of the trap mechanism. While cardboard is a particularly preferred material for the enclosure, other suitable materials include sheet polypropylene, polyethylene, polyvinyl and acetate. While a particularly preferred shape for the mousetrap enclosure is a wedge-shaped box, other shapes are conceivable such as rectangular, cylindrical or conical shaped enclosures or folding concertina shapes which are of a size adapted to accommodate a mouse, yet are still small enough so that the mouse is in a relatively confined space within the enclosure. Although it is envisaged that the mousetraps are for single-use (i.e, disposable after a mouse is trapped), the mousetraps may also be reusable. In this regard, so as to assist in the removal of the dead mouse, the mousetrap is able to be disassembled. This feature also advantageously assists in the cleaning of the mousetrap after removal of a dead mouse prior to resetting the mousetrap.
[0014] In a particularly preferred embodiment, the trap mechanism further comprises a bait housing. Preferably, the bait housing is situated on the trigger at a position so as to achieve a maximum possible distance between the bait and the enclosure opening is achieved. This ensures that the mouse is completely within the enclosure before trap occurs.
[0015] The present invention will now be described in detail with reference to a number of preferred embodiments as illustrated in the accompanying figures.
BRIEF DESCRIPTION OF THE FIGURES
[0016] FIG. 1 depicts a perspective view the mousetrap according to a preferred embodiment of the invention wherein the top and base are in the closed position.
[0017] FIG. 2 depicts a perspective view of the mousetrap according to FIG. 1 wherein the top and base are set in the set state ready for trapping a mouse.
[0018] FIG. 3 depicts a perspective view of the mousetrap according to FIG. 1 wherein a portion of the top has been omitted thereby revealing the internal parts of the mousetrap.
[0019] FIG. 4 a depicts a perspective view of the mousetrap according to FIG. 3 showing how the trigger is activated. FIGS. 4 b and 4 c depict perspective views of the top ( FIG. 4 b ) and the lever arrangement ( FIG. 4 c ) in accordance with another preferred embodiment of the invention. In FIG. 4 b, the top is shown from the underside with the stop means located in the top interior. In FIG. 4 c, the releasable catch means located on the lever arrangement is shown.
[0020] FIGS. 5 a, 5 b and 5 c depict, respectively, an exploded view of the mousetrap according to FIG. 1 showing the working interrelation of the internal parts of the mousetrap, a sectional view of the mousetrap and a perspective view showing the underside of the mousetrap.
[0021] FIGS. 6 a and 6 b depict plan views of two preferred embodiments of the mousetrap according to the invention, that show, in particular, preferred strike and catch plate configurations.
[0022] FIGS. 7 a and 7 b depict perspective views of a mousetrap according to another preferred embodiment of the invention in which the mousetrap is shown from the front ( FIG. 7 a ) and from the rear ( FIG. 7 b ).
[0023] FIGS. 8 a and 8 b depict, respectively, a perspective view of the mousetrap according to a preferred embodiment of the invention wherein the enclosure is shown as transparent body for the purpose of depicting trap mechanism location within the enclosure wherein the trap wire is in the set position and a perspective view of the mousetrap according to FIG. 8 a wherein the trap wire is in the trap position.
[0024] FIGS. 9 a and 9 b depict, respectively, a perspective view of the trap mechanism according to a preferred embodiment of the invention wherein the trap wire is in the set position and a perspective view of the trap mechanism according to a preferred embodiment of the invention wherein the trap wire is in a trap position.
[0025] FIG. 10 depicts a perspective view of the mousetrap according to another preferred embodiment of the invention in which a means for hanging the device is provided.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Referring to FIGS. 1 and 2 , the mousetrap according to a preferred embodiment of the invention includes an enclosure comprising a top ( 1 ), a base ( 3 ) and a closable aperture ( 5 ) within which a mouse is able to enter when the enclosure is in an open position. The mousetrap of FIG. 1 depicts the enclosure in a closed position. The enclosure is able to be moved from the closed position to the open position by the substantial alignment of the aperture ( 5 ) in the top ( 1 ) and the base ( 3 ). (see FIG. 2 ) To set the mousetrap enclosure from the closed position to an open position, the user, such as a homeowner, manually rotates the top relative to the base ( 3 ) in the counter-clockwise direction until the indentation ( 7 ) is aligned with the aperture ( 5 ). FIG. 2 shows the mousetrap when in the set position in which the aperture ( 5 ) and the indentation ( 7 ) are aligned.
[0027] In order to more fully describe the mousetrap according FIGS. 1 and 2 , the mousetrap is depicted in FIG. 3 with the top ( 1 ) omitted so as to show the internal parts of the mousetrap. The internal parts of the mousetrap comprise a trigger mechanism comprised of a lever arrangement ( 9 ) and a biasing means ( 11 ). Once the mousetrap has been set (i.e., the aperture is in the open position), a mouse will enter the enclosure through the aperture ( 5 ). The lever arrangement ( 9 ), when the mousetrap is in the set position, is engaged to a stop means ( 13 ) by virtue of a lever ( 9 a ) having a arm ( 9 b ), connected to a pivot means ( 9 c ). The pivot means ( 9 c ) allows the lever ( 9 a ) to be raised. Mice are very inquisitive animals and will thoroughly explore a new object put in their environment. In particular, mice will burrow and nest in confined spaces and they like to move with their body in contact with a wall. Generally, mice prefer small, tunnel-like or narrow-sided angular enclosures that have dark interiors. Dark interiors are generally explored before light interiors. As such, the configuration of the mousetrap according to this preferred embodiment is particularly attractive as the top ( 1 ) and base ( 3 ), fabricated from opaque materials, effectively form a tunnel-like enclosure with a dark interior.
[0028] FIG. 4 a shows how the mousetrap interior parts interact to allow the mousetrap to be set to trap a mouse and activated once a mouse has been trapped in accordance with a preferred embodiment of the invention. To set the trap, a user manually rotates the top ( 1 ) which is connected to a biasing means ( 11 ) in the anti-clockwise direction against the force of the biasing means ( 11 ) thereby storing potential energy within the biasing means ( 11 ). The top ( 1 ) is held in position (so that the aperture ( 5 ) is open) by engagement of the lever ( 9 a ) located on the lever arrangement ( 9 ) with a stop means ( 13 ). The mouse being an inquisitive creature, will enter the enclosure through the aperture ( 5 ) and travel through the enclosure in the anti-clockwise direction until it reaches the lever ( 9 a ). Due to its inquisitive nature and/or to the attractive odor of the bait, it will attempt to crawl through the gap ( 15 ) thereby causing the lever ( 9 a ) to raise. As the lever ( 9 a ) is raised, it disengages the stop means ( 13 ) causing the top to contra-rotate under the force of the biasing means so that the enclosure assumes the closed position (as is depicted in FIG. 1 ).
[0029] In another preferred embodiment of the invention, the enclosure is maintained in the open position against the force of the biasing means ( 11 ) by engagement of the stop means ( 13 ) located in the interior of the top ( 1 ) (as depicted in FIG. 4 b ) with a releasable catch means ( 9 d ) located on the lever arrangement ( 9 ) as shown in FIG. 4 c. As the mouse crawls through the gap ( 15 ) and raises the lever ( 9 a ), the lever arrangement ( 9 ) pivots by the pivot means ( 9 c ) and causes the releasable catch means ( 9 d ) located on the lever arrangement ( 9 ) to disengage the stop means ( 13 ). Once the lever arrangement ( 9 ) disengages the stop means ( 13 ), the top ( 1 ) contra-rotates relative to the base ( 3 ) under the action of the biasing means ( 11 ) so that the enclosure assumes the closed position (as depicted in FIG. 1 ).
[0030] The way in which the mousetrap is assembled is depicted in FIGS. 5 a and 5 b in which the mousetrap component parts are shown, respectively, in an exploded view in vertical alignment and also in section view. The mousetrap, in accordance with this particular embodiment, is fabricated from an injection mouldable material such as polypropylene and ABS, however materials such as polyethylene and polystyrene would also be suitable. Most of the component parts are adapted to snap into position and are assembled by a layering arrangement wherein the parts are sequentially arranged in position from the base ( 3 ) to the label ( 17 ) in the following way: the base ( 3 ) comprising a stop means ( 13 ) is adapted to retain a lever arrangement ( 9 ) that fits about a spindle ( 19 ), followed by positioning of the top ( 1 ) with the biasing means ( 11 ) inserted in a cavity ( 21 ) within the top ( 1 ). The biasing means is operably connected to the top( 1 ) and the base ( 3 ). In particular, FIG. 4 a depicts how the biasing means fits in relation to the base ( 3 ) and in particular, the spindle ( 19 ) forming part of the base ( 3 ). The label ( 17 ) is then positioned over the top ( 1 ) so as to conceal the biasing means ( 11 ). FIG. 5 b shows the sectional profiles of the top ( 1 ) and the base ( 3 ) to more clearly describe one possible method of configuring the top ( 1 ) and base ( 3 ) in such a way so that when in relation with the biasing means ( 11 ), contra-rotation of the top ( 1 ) relative to the base ( 3 ) under the force of the biasing means ( 11 ) is achieved. Also shown in this embodiment are the bait vents ( 23 ) which allow the mouse to sense the bait (not shown) when placed within the bait housing ( 25 ). FIG. 5 c shows the underside of the mousetrap, showing in particular, the bait housing ( 25 ) and how the bait may be inserted within the bait housing ( 25 ). This figure also shows the lip ( 27 ) on the base which allows one mousetrap to be stably and efficiently stacked on another mousetrap in accordance with a preferred embodiment of the invention.
[0031] Referring to FIGS. 6 a and 6 b , a mousetrap is depicted having stop means (in this embodiment the stop means also acts as a strike plate) ( 13 ) and a catch plate ( 14 ) that are be configured so as to have one or more projections ( 16 ). By virtue of these projections, more efficient incapacitation and/or kill of the mouse upon contact is achieved. In a particularly preferred embodiment, the projections are in the form of angular kinks in the strike and/or catch plate profiles. FIG. 6 a depicts a mousetrap having a curved strike plate ( 13 ) profile and a curved catch plate ( 14 ) profile. The curved strike plate ( 13 ) profile assists in guiding the mouse to the bait housing ( 25 ) while the projections ( 16 ) on the strike plate ( 13 ) and catch plate ( 14 ) aim to increase the impact force on the mouse. FIG. 6 b depicts a mousetrap having a strike plate ( 13 ) having multiple projections ( 16 ) (in this case in the form of a kink and a spike) and a catch plate ( 14 ) wherein the multiple projections ( 16 ) allow for different points of contact with the mouse thereby increasing the efficiency of incapacitation and/or kill.
[0032] Referring now to FIG. 7 a, the mousetrap in accordance with another preferred embodiment of the invention is depicted in which a front perspective view of mousetrap depicts the enclosure ( 30 ) having an aperture ( 32 ) through which a mouse is able to enter. A rear perspective view of the mousetrap is depicted in FIG. 7 b. This figure also depicts a slot ( 34 ) through which a tag ( 36 ) protrudes wherein the tag ( 36 ) is connected to the trap wire located with the enclosure interior. In this way, the trap wire (shown in FIG. 9 a ) is able to be set by a user externally of the enclosure ( 30 ).
[0033] FIGS. 8 a and 8 b show how the trap mechanism is disposed within the enclosure ( 30 ). In FIG. 8 a, the trap mechanism is in the set position in which the mouse, upon entry through the aperture ( 32 , see FIGS. 7 a, 7 b ), will travel through a gap ( 38 ) in the trap base ( 40 ) towards the rear of the enclosure ( 30 ). Once the trap wire ( 42 ) is caused to move from a first position as is depicted in FIG. 8 a to a second position as is depicted in FIG. 8 b, the mouse will be trapped between the trap wire ( 42 ) and the enclosure floor ( 44 ).
[0034] The trap mechanism according to a particularly preferred embodiment of the invention is depicted in the absence of the enclosure in FIGS. 9 a and 9 b. In this embodiment, the trap mechanism comprises a trap base ( 40 ), to which is connected a biasing means ( 46 ), a trigger ( 48 ) and the trap wire ( 42 ). The trap wire ( 42 ) is able to move from a first position (the trap position) (as is depicted in FIG. 9 b ) to a second position (the set position) (as is depicted in FIG. 9 a ) by pivot movement within a recess ( 50 ) formed within the trap base ( 40 ). To set the mousetrap, a user lifts and engages the trap wire ( 42 ) in the set position, the trap wire being retained in the set position against the force of the biasing means ( 46 ) by virtue of the shape of the base recess ( 50 ). That is, the trap wire ( 42 ), is held in the second (or set position) against the force of the biasing means ( 46 ) by an “over centre” spring action whereby the biasing means is extended, thereby storing potential energy, to an over-centre position and held in this over-centre position by engagement with an abutment (not shown) located within the recess ( 50 ). Upon depression of the trigger ( 48 ) by the mouse, the biasing means ( 46 ) is caused to contract past the over-centre position at which point the biasing means continues to contract, by release of the stored potential energy, causing the trap wire to move from the first to the second position thereby trapping the mouse. The trigger ( 48 ) is adapted so that it too is raised as the trap wire ( 42 ) is raised from the second (trap) to the first (set) position. Preferably, bait (not shown) is positioned on a bait housing ( 52 ) however due to their inquisitive nature, mice will still stand and depress the trigger ( 48 ) in the absence of bait. This will cause the trigger ( 48 ) to disengage from the trap wire ( 42 ), which through the force of the biasing means, will cause the trap wire ( 42 ) to move from the first (set) position to the second (trap) position, thereby trapping the mouse between the trap wire ( 42 ) and the enclosure floor ( 44 ). In this particular embodiment, the base is preferably formed from a injection mouldable component that is substantially rigid so as to withstand any stresses, such as bending or distortion of the enclosure, such that, advantageously, the trap mechanism is still able to function. In this way, the enclosure ( 30 ) may be fabricated out of a cheap material such as, for example, cardboard, but is still able to withstand any stress loads imposed on the mousetrap enclosure ( 30 ). Preferably, the trap base ( 40 ) is fabricated from ABS although materials such as polypropylene, polystyrene, pressed or folded metal, and wire forms are also suitable. It will be appreciated that the configuration of the trigger ( 48 ) in relation to the aperture ( 32 ) is such that after the mousetrap has been activated (or triggered), the aperture ( 32 ) is substantially closed so as to substantially conceal and isolate the trapped mouse from the external environment.
[0035] FIG. 10 depicts the mousetrap hung from, for example, a wall by a hang portion ( 54 ). In this way, the tab is used with pins, nails or screws to anchor the trap to narrow, raised surfaces such as, for example, shelves, roof or floor beams, rafters or ledges along which mice might be habitually travelling. The hang portion ( 54 ) may even be used for display or storage purposes.
[0036] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.
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Disclosed is a mousetrap having an enclosure with a rotatable top part having a downwardly extending strike plate within the enclosure, and a bottom part having an upwardly extending catch plate within the enclosure, an aperture in each of the top part and the bottom part which are in substantial alignment when the mousetrap is set, and a trigger mechanism, wherein the mousetrap is set to incapacitate or kill the mouse by the manual rotation of the top part relative to the bottom part when a mouse activates the trigger mechanism causing the top part to rotate relative to the bottom part and thereby incapacitating or killing the mouse between the strike plate and the catch plate.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part (CIP) of co-pending application U.S. Ser. No. 09/255,366, filed Feb. 23, 1999, in the name of Kynan L. Church for a “Hydraulically Actuated Valve Deactivating Roller Follower”.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
MICROFICHE APPENDIX
Not Applicable
BACKGROUND OF THE DISCLOSURE
The present invention relates to an improved valve train for an internal combustion engine, and more particularly, to a valve deactivator assembly for use therein, and even more particularly, to such a valve deactivator of the type utilizing a latching pin arrangement.
Although the valve deactivator assembly of the present invention may be utilized to introduce some additional lash into the valve train, such that the valves open and close by an amount less than the normal opening and closing, the invention is especially suited for introducing into the valve train sufficient lash (also referred to hereinafter as “lost motion”), such that the valves no longer open and close at all, and the invention will be described in connection therewith.
Valve deactivators of the general type to which the invention relates are known, especially in connection with internal combustion engines having push rod type valve gear train. In such a gear train, there is a rocker arm, with one end of the rocker arm engaging a push rod, and the other end engaging the engine poppet valve. Typically, a central portion of the rocker arm is fixed relative to the cylinder head (or other suitable structure) by a fulcrum arrangement as is well known to those skilled in the art, in which the fulcrum normally prevents movement of the central portion of the rocker arm in an “up and down” direction. At the same time, the fulcrum permits the rocker arm to engage in cyclical, pivotal movement, in response to the cyclical movement of the push rod, which results in the engagement of the push rod with the lobes of a rotating cam shaft.
There are a number of known valve deactivator assemblies which are operably associated with the fulcrum portion of the rocker arm in a push rod type valve gear train. Such known valve deactivator assemblies, when in the latched condition, restrain the fulcrum portion of the rocker arm to cause the rocker arm to move in its normal cyclical, pivotal movement. However, in an unlatched condition, the valve deactivator assembly permits the fulcrum portion of the rocker arm to engage in “lost motion” such that the cyclical, pivotal movement of the push rod causes the rocker arm to undergo cyclical, pivotal movement about the end which is in engagement with the engine poppet valve. In other words, the rocker arm merely pivots, but the engine poppet valve does not move, and hence, is in its deactivated condition.
A different approach to valve deactivation in a push rod type valve gear train is illustrated and described in copending application U.S.S.N. 09/255,366, filed Feb. 23, 1999 in the name of Kynan L. Church for a “Hydraulically Actuated Valve Deactivating Roller Follower”. In the copending application, the valve deactivation is accomplished in a roller follower of a type having an outer body which moves with the roller follower, and an inner body which imparts motion to the push rod. The valve deactivator has either an unlatched condition, in which lost motion occurs, or a latched condition, in which the inner and outer bodies are latched to each other and motion imparted to the roller follower by the cam is, in turn, transmitted to the push rod to provide normal valve opening and closing.
A generally similar type of valve deactivator is illustrated and described in U.S. Pat. No. 5,655,487, for use in an overhead cam (“OHC”) engine, of the type utilizing an end pivot rocker arm. In a valve gear train of the type described above, the pivot point for the end of the rocker arm is a hydraulic lash adjuster (“HLA”), with the opposite end of the rocker arm being in engagement with the engine poppet valve.
In the valve deactivator of the above-cited patent, the latching arrangement between the inner and outer bodies is configured such that the inner body must be maintained in a predetermined rotational orientation within the outer body, in order for proper latching and unlatching to occur. Such a need for maintaining rotational orientation of the inner body member, relative to the outer body member, adds substantially to the overall complexity and cost of both the manufacture and assembly of the valve deactivating HLA. In connection with the development of the present invention, it has also been determined that another disadvantage of the valve deactivator of the cited patent is that, when the latching mechanism is latched, all of the gear train force being supported by the latching mechanism is being carried over a relatively small area, thus resulting in higher than desirable surface stresses in the latch mechanism.
BRIEF SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved valve deactivator assembly which overcomes the above-described disadvantages of the prior art.
It is a more specific object of the present invention to provide an improved valve deactivator assembly wherein the inner body member does not need to be in any particular rotational orientation relative to the outer body member, in order for proper latching and unlatching to occur.
It is a related object of the present invention to provide an improved valve deactivating HLA for use in OHC valve gear train of the end pivot rocker arm type, in which the HLA is reasonably compact, to minimize the need for overall re-design of the valve gear train.
The above and other objects of the invention are accomplished by the provision of an improved valve deactivator assembly for an internal combustion engine of the type having valve means for controlling the flow to and from a combustion chamber, drive means for providing cyclical motion for opening and closing the valve means in timed relationship to the events in the combustion chamber, and valve gear means operative in response to the cyclical motion to effect cyclical opening and closing of the valve means. The valve deactivator assembly comprises part of the valve gear means and includes an outer body member and an inner body member disposed within the outer body member and being reciprocable relative thereto, and a spring biasing the inner body member toward an axially extended position relative to the outer body member. A latch assembly is wholly disposed within the inner body member when the outer and inner body members are in an unlatched condition, the latch assembly including a radially moveable latch member and spring means biasing the latch member toward a latched condition. A source of pressurized fluid is operably associated with the latch assembly and is operable to bias the latch member toward the unlatched condition.
The improved valve deactivator assembly is characterized by the latch assembly further comprising the outer body member defining a generally annular, internal groove including an annular latch surface and at least one fluid port disposed in open fluid communication with the annular internal groove and in fluid communication with the source of pressurized fluid. The latch member defines a generally planar stop surface oriented generally parallel to the annular latch surface and disposed for face-to-face engagement therewith when the latch member is in the latched condition, whereby the inner body member may be in any rotational orientation relative to the outer body member.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary, axial cross-section taken through a vehicle internal combustion engine, illustrating a typical valve gear train of the type with which the present invention may be utilized.
FIG. 2 is a greatly enlarged, axial cross-section illustrating the valve deactivator assembly of the present invention in its unlatched condition.
FIG. 3 is a further enlarged, fragmentary, axial cross-section of a portion of the valve deactivator assembly of the present invention in its latched condition.
FIG. 4 is a transverse cross-section, taken on line 4 - 4 of FIG. 3, but with the latching elements retracted, illustrating one important aspect of the present invention.
FIG. 5 is a view taken on line 5 - 5 of FIG. 4 .
FIG. 6 is a view showing an alternative latching means using a wire annular ring.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, which are not intended to limit the invention, there is illustrated, by way of example only, an OHC valve gear train of the type which may utilize the valve deactivator assembly of the present invention. In FIG. 1, there is shown fragmentarily a cylinder head 11 of an internal combustion engine. The cylinder head 11 defines a generally cylindrical bore 13 within which is disposed a valve deactivator assembly, generally designated 15 .
The valve deactivator assembly 15 includes an outer body member 17 , an inner body member 19 , and a plunger element (to be described subsequently) which includes a ball plunger portion 21 . As is well known to those skilled in the art, the cylinder head 11 also defines an engine oil passage 23 which intersects the bore 13 , and by means of which pressurized oil is communicated to the valve deactivator assembly 15 , as will be described in greater detail subsequently.
Referring still primarily to FIG. 1, the ball plunger portion 21 is received within a hemispherical socket 25 of a rocker arm 27 . At the end of the rocker arm 27 opposite the socket 25 is a valve contacting pad 29 , the underside of which is in engagement with the tip 31 of an engine poppet valve 33 (of which only the upper portion of the stem is shown). The rocker arm 27 includes a rotatable cam follower 35 , which is in engagement with the surface of a valve actuating cam 37 .
Typically, but by way of example only, the present invention would be utilized with an eight cylinder engine for which the valve gear train would include eight pairs of intake and exhaust valve rocker arms, with four of the eight being equipped with the valve deactivator assembly 15 of the present invention. In other words, four of the eight cylinders could be selectively deactivated by introducing sufficient lost motion into the valve drive train for that particular valve, so that the cyclical motion of the cam 37 does not result in any corresponding cyclical opening and closing movement of the poppet valve 33 (i.e., of either the intake valve or the exhaust valve for that particular cylinder). Under the “deactivated” condition described, the engine poppet valve 33 remains closed under the influence of a valve closing spring (not shown herein). It would also be typical that, for the four cylinders which cannot be selectively deactivated, the socket 25 of the rocker arm 27 would engage the ball plunger portion of a “conventional” hydraulic lash adjuster, i.e., an HLA not having valve deactivation capability.
When the lobe of the cam 37 engages the follower 35 (as shown in FIG. 1 ), under normal operating conditions, the ball plunger portion 21 would comprise the pivot point for the rocker arm 27 , such that the rocker arm would pivot about the ball plunger portion 21 as the follower 35 is engaged by the cam lobe 37 , thus forcing the engine poppet valve 33 in a downward direction.
Referring now primarily to FIG. 2, those skilled in the art should understand that the invention is not limited to any particular valve deactivator or HLA configuration, except as is noted hereinafter in the appended claims. Thus, the present invention is being illustrated and described in connection with a valve deactivating HLA for use with an end pivot rocker arm, but the invention could also be utilized in, for example, a valve deactivating roller follower for a push rod type gear train.
In FIG. 2, the valve deactivator assembly 15 is shown in its unlatched condition, with the inner body member 19 and ball plunger portion 21 fully “retracted”, i.e., moved as far downward as possible within the outer body member 17 . Disposed in engagement with an internal groove formed in the outer body member 17 is a stop clip 39 which serves as the lower spring seat for a lost motion compression spring 41 . At its upper end, the spring 41 is seated against a pilot ring 43 , which is preferably fixed to move with the upper end of the inner body member 19 by any suitable means, such as a wire snap ring 45 . Thus, the compression spring 41 biases the inner body member 19 and the ball plunger portion 21 “upward” in FIG. 2, toward a fully extended condition (the condition shown in FIG. 3 ), in the absence of a downward force being exerted on the ball plunger 21 by the socket 25 of the rocker arm 27 , when the lobe of the cam 37 is in the position shown in FIG. 1 .
Referring still primarily to FIG. 2, the ball plunger portion 21 is formed at the upper end of a generally cylindrical plunger element 47 which is retained for limited reciprocal movement within the inner body member 19 by means of a wire snap ring 49 . The inner body member 19 defines a stepped bore 51 which serves as the high pressure chamber for a hydraulic lash compensation element, generally designated 53 , which may be of a type well known to those skilled in the art, is not an essential feature of the invention, and will not be described further herein. Disposed within the plunger element 47 is a fluid reservoir 55 , which is in fluid communication with the high pressure chamber 51 by means of the lash compensation element 53 , in a manner well known to those skilled in the art.
Disposed between the outer body member 17 and the inner body member 19 is a generally cylindrical chamber 57 , in which the compression spring 41 is disposed. The chamber 57 would typically be filled with engine lubricating oil, some of which would enter through a port 59 formed in the wall of the outer body member 17 .
The lower portion of the inner body member 19 defines a pair of diametrically arranged bores 61 which, by way of example only, are illustrated herein as being generally cylindrical, but may be of a variety of configurations. Disposed within each bore 61 is a latching element 63 , and in the subject embodiment, the latching members 63 are identical, and thus may be interchangeable. Preferably, the latching elements 63 are hollow to receive therein a single compression spring 65 . With the bores 61 arranged diametrically, a single spring 65 is sufficient to bias both latching elements 63 radially outward toward a latched condition (as shown in FIG. 3 ).
Referring now to FIGS. 2 and 3 together, the outer body member 17 defines, by way of example only, a pair of ports 67 , at least one of which is in communication with the engine oil passage 23 (see FIG. 1 ). The ports 67 open into an annular, internal groove 69 , the groove 69 forming an annular latch surface 71 (see FIG. 4 ). Each of the latching elements 63 includes a latch portion 73 , each of which is generally half-circular (see FIG. 5 ), and each of which includes on its underside, a generally flat, planar stop surface 75 . Each latch portion 73 includes a radially outer end surface 77 , which in the subject embodiment, has about the same radius of curvature as the adjacent annular, internal groove 69 .
Each latching element 63 defines a flat 79 , which is preferably perpendicular to the planar stop surface 75 . Adjacent each flat 79 , the inner body member 19 defines a vertical bore 80 , and into each bore 80 , after the latching elements 63 are in place in the bores 61 , a pin 81 is pressed in and is disposed closely spaced apart from the flat 79 , as shown in FIG. 4 . The pins 81 serve two primary functions, one of which is to retain the latching elements 63 within the bores 61 as the inner body member 19 is handled during assembly of the entire deactivator assembly 15 . The other function is to maintain the rotational orientation of each latching element 63 within its bore 61 , as shown in FIG. 5, so that both of the planar stop surfaces 75 will always remain substantially parallel to the annular latch surface 71 .
As a result of the above-described parallel relationship of the surfaces 71 and 75 , the inner body member 19 can have any rotational orientation within the outer body member 17 , and proper latching will still occur, which is one important aspect of the present invention. In other words, although in FIG. 4 the latch portion 73 is shown as disposed adjacent the ports 67 , such is not necessary, and the inner body member 19 could be inserted within the outer body member 17 at any relative rotational orientation. Another result of the parallel relationship of the surfaces 71 and 75 is that any forces exerted on the deactivator assembly 15 are taken up by the face-to-face engagement of the two planar stop surfaces 75 and the annular latch surface 71 , rather than by a cylindrical member within a circular opening (line-to-line contact) as was known in the prior art.
When it is desired to deactivate the engine poppet valve 33 from the latched condition shown in FIG. 3, an appropriate signal is transmitted to the engine oil pressure system, increasing the oil pressure in the engine oil passage 23 . The increased oil pressure is communicated through one of the ports 67 , filling the annular, internal groove 69 with pressurized fluid. The pressurized fluid contacts the end surfaces 77 of the latch portions 73 , biasing the latching elements 63 from the latched condition shown in FIG. 3 toward an unlatched condition as shown in FIG. 4, with the stop surfaces 75 retracted and out of engagement with the annular latch surface 71 . With the latching elements 63 in their unlatched condition, the inner body member 19 may be moved by external forces (as explained previously) from its filly extended position as shown in FIG. 3 to its fully retracted position as shown in FIG. 2, thus introducing lost motion into the valve gear train.
As is typical in the valve deactivator art, mode transitions, either from the latched condition to the unlatched condition, or vice versa, occur only when the cam 37 is on the base circle portion. As is well known to those skilled in the art, mode transitions are accomplished only on base circle in order that the mode change occurs while the valve deactivator assembly 15 , and more specifically, the latching mechanism, is not under load. For example, in FIG. 3, even though the valve deactivator assembly 15 is in the latched condition, when the cam 37 has its base circle portion engaging the follower 35 , the latching elements 63 can easily be slid from the latched condition shown to the unlatched condition. However, after the cam 37 rotates to the position shown in FIG. 1, there is sufficient downward force on the ball plunger 21 , and thus on the inner body member 19 , such that the frictional engagement force between the annular latch surface 71 and the stop surfaces 75 would be enough such that the latching elements 63 could not be biased radially inward to their unlatched positions, except perhaps with substantially higher fluid pressure. Those skilled in the art will understand that such fluid pressures of the type which would be required are generally not available and would probably not be desirable.
FIG. 6 illustrates the invention in a slightly different form for use in connection with a specific valve train, using a wire annular ring 82 to orient the latch member 63 .
The invention has been described in great detail in the foregoing specification, and it is believed that various alterations and modifications of the invention will become apparent to those skilled in the art from a reading and understanding of the specification. It is intended that all such alterations and modifications are included in the invention, insofar as they come within the scope of the appended claims.
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The invention is a valve deactivator assembly ( 15 ) for use in connection with a valve train of an internal combustion engine. In application, a pre-selected number of the engine cylinders would each be equipped with a deactivator connected to its intake engine valve. Upon driver selection or predetermined road conditions, sufficient lost motion would be introduced into the valve train so that the valve would remain closed and the cylinder deactivated as the engine is in operation. The deactivator has in its inner body ( 19 ) a latch assembly that is in a latched condition for normal operation of the valve train. When it is desired to retain the valve in the closed position and deactivate a cylinder, the latch assembly is caused to be moved to the unlatched condition by increase in the pressure of the engine oil. When the latch assembly is unlatched, significant lost motion is introduced into the valve train causing the valve to remain closed and the cylinder is deactivated.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to novel disubstituted or deoxydisubstituted α-D-lyxofuranosides, their synthesis, and intermediates for preparing these compounds. More specifically, the present invention relates to alkyl, alkoxyalkyl, or aralkyl 2,3-0-(1-methlethylidene) -α-D-lyxofuranosides unsubstituted or substituted at the 5-position. This invention further relates to the replacement of oxygen at 5-position of lyxofuranosides by N or S to form 5-deoxy-5-amino substituted or 5-deoxy-5-thio substituted lyxofuranosides. These compounds show significant anti-inflammatory and anti-proliferative activity and are useful for treating warm blooded animals and mammals with rheumatoid arthritis, osteoarthritis, scleroderma, systemic lupus erythematosus, autoimmune deficiency syndrome, atopic dermatitis, cancer (particularly colon and melanoma), and psoriasis. Thus, this invention also relates to the pharmaceutical compositions containing lyxofuranoside compounds and methods of treating inflammatory and/or autoimmune disorders.
2. Description of the Related Art
The most reactive functional group in D-lyxose is the anomeric hydroxyl group. A glycoside is formed when the hydrogen atom of an anomeric hydroxyl group is replaced by a substituted or unsubstituted carbon atom. Typically, glycosides are formed either for group protection or as part of the synthesis of a larger molecule. The Fischer Method is particularly effective for synthesizing glycosides from unprotected reducing sugars and low molecular weight alcohols. After the glycosides are formed, various blocking methods are used to block or protect one or more of the hydroxyl group(s) thus leaving one or two hydroxyls free to derivatize. Isopropylidene and benzylidene groups are the most commonly used protective groups in carbohydrate chemistry. These groups are introduced into a molecule under similar conditions; however, the location of the protection can be quite different. The reason for this difference is directly related to the stability of each protected molecule. Since protection normally occurs under conditions which allow reversibility, reaction proceeds until equilibrium is reached. The distribution of products at equilibrium is determined by their relative thermodynamic stabilities. In other words, these reactions are thermodynamically controlled. Benzylidene groups prefer to be part of six-membered ring acetals, while the ketals resulting from acetonation generally are 5-membered rings. The difference is attributed to the effect of the methyl and phenyl substituents on the stability of the particular ring systems. These blocking methods are described in U.S. Pat. Nos. 2,715,121, 4,056,322, 4,735,934, 4,996,195, and 5,010,054 the disclosure of which are incorporated herein by reference. Other blocking methods are described in J. Carbohydr. Chem., 4, 227 (1985); 3, 331 (1984); Methods in Carbohydr. Chem., 1, 191 (1962); 1, 107 (1962); Can. J. Chem., 62, 2728 (1984); 47, 1195, 1455 (1969); 48, 1754 (1970). The therapeutic activity of hexoses and their derivatives are also disclosed in several of the above references.
A well known derivative of α-D glucose having beneficial therapeutic properties is Amiprilose. HCl, 1,2-0-isopropylidene-3-0-3'-(N',N'-dimethylaminopropyl)-α-D-glucofuranose. This compound, which is in late Phase III clinical trials, is known to have anti-inflammatory activity and demonstrated utility in managing the signs and symptoms of rheumatoid arthritis.
Unfortunately, while some of the prior art hexose derivatives have shown beneficial therapeutic activity, high doses of these compounds, including Amiprilose. HCl, are often needed to be effective and produce the desired results. Therefore, the prior art derivatives are difficult to prescribe orally. Because, therapy for inflammatory and autoimmune disorders is often midterm and long-term, there is a need to develop potent, non-toxic compounds which can be orally administered to promote ease of treatment and patient compliance.
One object of the present invention, therefore, is to provide a new class of compounds (pentofuranoside derivatives) that exhibit significantly greater potency than available compounds in order to provide ease of treatment, particularly oral administration. It is believed that the compounds of the present invention act by a different mechanism than Amiprilose. HCl and are more selective in their activity.
Another object of the present invention is to provide novel carbohydrate compounds (pentoses) that exhibit significantly greater potency for cancer treatment (particularly melanoma and colon cancer). There is no example available in the literature wherein pentoses, particularly lyxofuranoside derivatives, are used for treating cancer patients (particularly for treating melanoma and colon cancer patients).
Another object of the present invention is to provide a novel class of disubstituted or deoxy disubstituted lyxofuranoside compounds which exhibit anti-inflammatory and anti-proliferative activity. It is also an object of the present invention to provide novel compounds and compositions which are useful in the treatment of warm blooded animals and mammals having anti-inflammatory and/or autoimmune disorders. It is a further object of this invention to provide a novel, simple, and efficient process for preparing alkyl, aryl, aralkyl, or heterocyclic alkyl 2,3-0-(1-methlethylidene)-α-D-lyxofuranoside compounds.
A still further object of this invention to provide novel compounds that exhibit significantly increased potency over available compounds, such as Therafectin (Amiprilose. HCl), in order to provide ease of oral administration.
SUMMARY OF THE INVENTION
In order to achieve the above-mentioned objects and in accordance with the purpose of the invention as embodied and broadly described herein, there is provided a α-D-lyxofuranoside having the following general formula I: ##STR1## wherein
R is H, C 5 -C 15 -alkyl, n-C 5 -C 15 -alkyloxy-C 2 -C 4 -alkyl (preferably n-nonyloxypropyl and n-decyloxypropyl), and phenylpropyl;
R 1 is --YR 2 , pyrrolidinyl, piperidinyl, morpholinyl, C 5 -C 15 -alkylamino, hexamethyleneimino, amino-C 2 C 4 -pyrrolidinyl (preferably C 2 ), amino-C 2 -C 5 -pyrrolidinyl (preferably n-C 3 ), amino-C 2 -C 4 -morpholinyl (preferably C 2 ), or amino-C 2 -C 4 -piperidinyl (preferably C 2 );
wherein Y is O or S and
R 2 is C 5 -C 15 -alkyl, N-C 2 -C 4 -pyrrolidinyl (preferably N-ethyl) N-C 2 -C 4 -piperidinyl (preferably N-ethyl), N-C 2 -C 4 -morpholinyl (preferably N-ethyl), N,N-dimethylaminopropyl, or hexamethyleneiminoethyl;
where nonyloxypropyl is--(CH 2 ) 3 -0-(CH 2 ) 8 CH 3
where N-C 2 -C 4 piperidinyl is ##STR2##
where pyrrolidinyl is ##STR3##
where aminoethylpyrrolidinyl is ##STR4## etc.
The present invention also provides pharmaceutical compositions for the treatment of inflammatory and/or autoimmune disorders. These compositions comprise an effective amount of at least one of the above-described lyxofuranoside compounds, or a physiological acceptable acid-addition salt thereof, with at least one pharmaceutically acceptable carrier. The lyxofuranoside compounds (pentose derivatives) of the present invention exhibit greater potency in terms of their activity (Con-A, Fibroblast, and Mixed Lymphocyte Response) than known glucofuranose compound (hexose derivative), such as THERAFECTIN (Amiprilose. HCl). These novel compounds have demonstrated in vitro decreased skin cell proliferation and the inhibition of the proliferative response of splenic T-lymphocytes to known mitogen. Since T-lymphocytes are the immune cells that regulate immune responses of the compounds of the present invention can be used for treating warm blooded animals and mammals with inflammatory and/or autoimmune disorders such as rheumatoid arthritis, osteoarthritis, psoriasis, atopic dermatitis, scleroderma, systemic lupus erythematosus, and autoimmune deficiency syndrome. These compounds have also demonstrated a significant anti-cancer activity (particularly against melanoma and colon cancer) in in vitro screens. Also the compounds of the present invention can be administered internally or externally.
As mentioned above, the present invention is also directed to the novel synthesis of alkyl, alkoxyalkyl, aralkyl, or heterocyclic alkyl 2,3-0-(1-methlethylidene)-α-D-lyxofuranosides which are obtained in very good yield by periodate oxidation followed by reduction of the corresponding α-D-mannofuranoside.
DETAILED DESCRIPTION OF THE INVENTION
The compounds of the present invention are prepared by the following reaction sequences: ##STR5##
In scheme 1, D-lyxose is first treated with 2-methoxypropene to block 2,3-positions leaving behind only two hydroxyl groups, one at the anomeric position and the other at 5-position which are free to derivatize. The anomeric hydroxyl group, being more reactive, is then treated with a suitable alcohol in the presence of an acid catalyst form a glycoside. Alternatively, in scheme 2, D-mannose is treated with an aldehyde or ketone to block the 2,3 and 5,6-positions leaving only one hydroxyl group at the anomeric position free to derivatize. The anomeric hydroxyl group is then treated with an appropriate alcohol in the presence of acid catalyst to form a glycoside. The 5,6-blocked substituent could then be removed selectively, oxidized with periodate, and reduced to obtain the corresponding lyxofuranoside in good yields. These compounds are then treated with the desired side chains or are derivatized further. These compounds represent a novel class of compounds and there is no example available thus far wherein glycosides of disubstituted or deoxy disubstituted lyxofuranoses (pentoses) are used as a therapy for inflammatory or autoimmune disorders.
The compounds produced by these reactions are:
I. n-Dodecyl 2,3-0-(1-methlethylidene)-α-D-lyxofuranoside
II. n-Nonoyloxypropyl 2,3-0-(1-methlethylidene)-α-D-lyxofuranoside
III. n-Nonoyloxypropyl 2,3-0-(1-methlethylidene)-5-0-decyl-α-D-lyxofuranoside
IV. n-Nonyloxypropyl 2,3-0-(1-methlethylidene)-5-0-(N',N'-dimethylamino-n-propyl)-α-D-lyxofuranoside
V. n-Nonyloxypropyl 2,3-0-(1-methlethylidene)-5-0-N'-ethylpyrrolidinyl-α-D-lyxofuranoside
VI. n-Nonyloxypropyl 2,3-0-(1-methlethylidene)-5-0-N'-ethylpiperidinyl-α-D-lyxofuranoside
VII. n-Nonyloxypropyl 2,3-0-(1-methlethylidene)-5-0-N'-ethylmorpholinyl-α-D-lyxofuranoside
VIII. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-hexamethyleneiminoethyl-α-D-lyxofuranoside
IX. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-decyl-α-D-lyxofuranoside
X. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-(N',N'-dimethylamino-n-propyl-α-D-lyxofuranoside
XI. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-N-ethylpyrrolidinyl-α-D-lyxofuranoside
XII. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylpiperidinyl-α-D-lyxofuranoside
XIII. n-Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylmorpholinyl-α-D-lyxofuranoside
XIV. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-hexamethyleneiminoethyl-α-D-lyxofuranoside
XV. n-Dodecyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpyrrolidinyl-α-D-lyxofuranoside
XVI. n-Nonoyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-pyrrolidinyl-α-D-lyxofuranoside
XVII. n-Nonoyloxypropyl-5-deoxy-2,3-0-(1-methylethylidene)-5-piperidinyl-α-D-lyxofuranoside
XVIII. n-Nonyloxypropyl-5-deoxy-2,3-0-(1-methylethylidene)-5-morphilinyl-α-D-lyxofuranoside
XIX. n-Nonyloxypropyl 5-deoxy 2,3-0-(1-methylethylidene)-5-aminoheptyl-α-D-lyxofuranoside
XX. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpiperidinyl-α-D-lyxofuranoside
XXI. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylmorpholinyl-α-D-lyxofuranoside
XXII. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-hexamethyleneiminoethyl-α-D-lyxofuranoside
XXIII. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpyrrolidinyl-α-D-lyxofuranoside
XXIV. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminopropylpyrrolidinyl-α-D-lyxofuranoside
XXV. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-pyrrolidinyl-α-D-lyxofuranoside
XXVI. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-piperidinyl-α-D-lyxofuranoside
XXVII. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-morpholinyl-α-D-lyxofuranoside
XXVIII. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-hexamethyleneimino-α-D-lyxofuranoside
XXIX. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminononyl-α-D-lyxofuranoside
XXX. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpyrrolidene-U-D-lyxofuranoside
XXXI. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminopropylpyrrolidinyl-α-D-lyxofuranoside
XXXII. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpiperidinyl-α-D-lyxofuranoside
XXXIII. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylmorpholinyl-α-D-lyxofuranoside
XXXIV. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-S-n-decylα-D-lyxofuranoside
XXXV. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-S-ethylpyrrolidinyl-α-D-lyxofuranoside
XXXVI. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-S-ethylmorpholinyl-α-D-lyxofuranoside
XXXVII. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-S-ethylpiperidinyl-α-D-lyxofuranoside
A simple and efficient process for the synthesis of alkyl or substituted alkyl, aralkyl, or heterocyclic alkyl 2,3-(1-methylethylidene)-α-D-lyxofuranoside compounds is described above, which starts by reacting D-mannose with acetone and a suitable alcohol in the presence of a catalytic amount of concentrated sulfuric acid. The product obtained is hydrolysed selectively at 5,6-position followed by periodate oxidation and then reduced with sodium borohydride.
The disubstituted and deoxy disubstituted glycosides of lyxofuranoside derivatives of the present invention exhibit various pharmacological properties and are, therefore, useful for treating animals and mammals with inflammatory and or autoimmune disorders. Several intermediates described herein may be prepared by methods described in my copending U.S. application, Ser. No. 07/923,452.
The free amino compounds described above are basic and form organic and inorganic acid salts which are useful in the therapeutic composition and method of invention. These may be prepared by the usual prior art techniques, such as suspending the compound in water and then adding exactly one equivalent of the desired organic acid or mineral acid. Examples of suitable acids include HCl, H 2 SO 4 , HNO 3 , maleic acid, benzoic acid, tartaric acid, acetic acid, p-aminobenzoic acid, oxalic acid, succinic acid, and glucuronic acid. The neutral solution of the resulting salt is subjected to rotary evaporation under diminished pressure to the volume necessary to assure precipitation of the salt upon cooling, which is then filtered and dried. The salts of the present invention may also be prepared strictly under non-aqueous conditions, for example, dissolving the free amine in ether and adding exactly one equivalent of the desired acid in ether. Stirrina the solution at 0°-5° C. causes the precipitation of the amine salt which are filtered, washed with ether and dried. The amine salts are often preferred for use in formulating the therapeutic compositions of the invention as they are crystalline and relatively more stable and non-hygroscopic. The amine salts are also better adapted for intramuscular injection than are the free amines.
Because of their valuable pharmacological properties, the compounds of the present invention may be administered to human patients or to animals either orally, topically, rectally, internasally or by parenteral administration. When the therapeutic composition is to be administered orally, the compounds of the present invention may be admixed with a prior art filler and or binder such as starch, and, if desired, a disintegrator, and the admixture pressed into a tablet of a size convenient for oral administration. Capsules also may be filled with the powdered therapeutic composition and administered orally. Alternatively, a water solution of the amine salt or suspension of the therapeutic composition may be admixed with a flavored syrup and administered orally. A salt of the free amine is usually preferred where the compound is administered by intramuscular injection.
The present pharmaceutical compositions are preferably produced and administered in dosage units, each unit containing as active component a certain amount of at least one compound of the present invention and or at least one of its physiologically acceptable acid addition salts. The dosage may be varied over extremely wide limits as the compounds are effective at low dosage levels are relatively free of toxicity. The compounds may be administered in the minimum quantity which is therapeutically effective, and the dosage may be increased as desired up to the maximum dosage tolerated by the patient. In the case of an animal or human, the effective dose to treat autoimmune and or anti-inflammatory disorders can range from 1 to 50 mg per kilogram of body weight per day, preferably an amount of about 2-30 mg per kilogram per day, over a period required for the treatment. In the case of in vitro testing, the effective amount necessary to achieve 50% inhibition of the cultured cells ranges from 1-100 μg per ml of the cultured medium, preferably 2-50 μg per ml.
The following examples demonstrate the synthesis of several compounds according to this invention and illustrate the beneficial therapeutic properties of these compounds. The examples described are illustrative, and are not to be considered as limitative in any manner of the claims which follow.
EXPERIMENTAL PROCEDURE
Various solvents, such as acetone, methanol, pyridine, tetrahydrofuran, dimethylsulfoxide, ether, hexanes, and ethylacetate were dried using various drying reagents by the procedure as described in the literature. Wet solvents gave poor yields of the products or intermediates. IR spectra were recorded as nujol mulls or a thin neat film on a Beckman Instrument using sodium chloride plates. PMR, CMR, and various 2D spectra were recorded on a Varian XL-300 MHz instrument using tetramethylsilane as an internal standard reference. CIMS were obtained on a Finnigan MAT-4510 mass spectrometer equipped with an INCOS data system. Generally, a direct exposure probe was used and methane was used as a reagent gas (0.35 mm Hg, 120° C. source temperature).
EXAMPLE 1
Preparation of Phenylpropyl 2,3-0-(1-methylethylidene)-α-D-lyxofuranoside
Scheme 1:
Phenylpropyl 2,3-0-(1-methylethylidene)-α-D-mannofuranoside (prepared as described in U.S. application Ser. No. 07/923,452 (20.0 gms) was suspended in water (40 ml) and the flask cooled to 0°-5° C. Sodium periodate (20 gms) was dissolved in water (40 ml) by warming and added to the above solution slowly (5 min). The reaction mixture was stirred at the same temperature for 30 minutes and then 200 ml of ethanol was added to precipitate out all the salts. Filtered off the salts and washed with 50 ml more of ethanol. The solvents were removed from the liltrate and the residue dissolved in ether (200 ml), dried over MgS 4 , filtered, and solvent removed.
The crude aldehyde so formed was dissolved in methanol (200 ml) and added sodium borohydride (7 gm) in portions, at 5°-10° C. The reaction mixture was stirred at the same temperature for 90 minutes. The excess sodium borohydride was then decomposed by the addition of acetone (10 ml) and the resulting solution subjected to rotary evaporation to remove all the solvents. The residue was dissolved in ethylacetate (200 ml) and washed with brine (30 ml). The organic layer was dried over magnesium sulfate, filtered, and solvent removed. The product so obtained showed a single homogenous spot on a TLC plate and could be used in further steps without any further purification. The yield of the pure viscous oil was 15 g (82.3%).
CIMS: 309 (M+l).
Scheme 2:
To a solution of D-lyxose (30 g) in dry DMF (150 ml) at 0° C. was added 2-methoxypropene (40 ml, 2 eq.) and a catalytic amount of p-toluenesulfonic acid (1 g). After stirring at 0°-5° C. for 3 hours, the reaction mixture was neutralized with triethylamine. The solvents were then stripped off and the residue was purified by column chromatography using 50% ethylacetate in hexane. The yield of the pure product, 2,3-0-(1-methylethylidene)-α-D-lyxofuranose was 52%, m.p. 82°-83° C. (literature m.p. 80°-82° C., Carbohydrate Research, 219,115(1991).
The lyxofuranose (5 gm) obtained above was dissolved in dioxane (30 ml) and added 3-phenyl-l-propanol (5 ml) and a catalytic amount of concentrated sulfuric acid (5 drops). The reaction mixture was refluxed for one hour and then cooled to ambient temperature. Neutralized the reaction with triethylamine and stripped off the solvents. The residue was dissolved in ethylacetate (100 ml), washed with water (1×10 ml) , the organic layer dried (MgSO 4 , filtered and solvent removed. The product, phenylpropyl 2,3-0-(1-methylethylidene)-α-D-lyxofuranoside, was purified by flash chromatography. The yield of the pure product was 84%.
CIMS: 309 (M+l).
Other compounds which were prepared similarly as described in Example 1 (Schemes 1 and 2) are:
i. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-α-D-lyxofuranoside.
ii. n-Dodecyl 2,3-0-(1-methylethylidene)-α-D-lyxofuranoside.
EXAMPLE 2
Preparation of phenylpropyl 2,3-0-(1-methylethylidene)-5-0-n-decyl-α-D-lyxofuranoside.
Sodium hydride (60%, 0.4 g) was made free of oil by washing with hexane and added dry DMSO (20 ml). To this stirred solution was added a solution of phenylpropyl 2,3-0-(1-methylethylidene)-α-D-lyxofuranoside (3.08 g; 0.01 mol) in DMSO (10 ml), dropwise, over a period of 10 minutes at room temperature. The reaction was stirred at the same temperature for 30 minutes. 1-Bromodecane (2.65 g; 0,012 mol) was then added dropwise over a period of ten minutes and the mixture stirred for another 3 hours. The reaction mixture was poured into ice cold water (200 ml) and extracted with ether (3×50 ml). The combined ether extract was washed once with water (20 ml), ether layer dried (MgSO 4 ), filtered and solvent removed. The crude product so obtained was purified by flash chromatography using 5% ethylacetate in hexane. The yield of pure product (viscous oil) was 96%. CIMS: 449 (M+l)
Other compounds which were prepared as described in Example 2 are:
1. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-dodecyl-α-D-lyxofuranoside
2. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-(N',N'-dimethylamino-n-propyl)-α-D-lyxofuranoside
3. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylpyrrolidinyl-α-D-lyxofuranoside
4. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylpiperidinyl-α-D-lyxofuranoside
5. n-Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylmorpholinyl-α-D-lyxofuranoside
6. Phenylpropyl 2,3-0-(1-methylethylidene)-5-0-hexamethyleneiminoethyl-α-D-lyxofuranoside
EXAMPLE 3
Preparation of n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-decyl-α-D-lyxofuranoside
Sodium hydride (60%, 0.4 g) was made free of oil by washing with hexane and added dry DMSO (20 ml). To this stirred solution was added a solution of n-nonyloxypropyl 2,3-0-(1-methylethylidene)-α-D-lyxofuranoside (3.74 g; 0.01 mol) in DMSO (10 ml), dropwise, over a period of 10 minutes at room temperature. The reaction was stirred at the same temperature for 30 minutes. 1-Bromodecane (2.65 g; 0,012 mol) was then added dropwise over a period of ten minutes and the mixture stirred for another 3 hours. The reaction mixture was poured into ice cold water (200 ml) and extracted with ether (3×50 ml). The combined ether extract was washed once with water (20 ml), ether layer dried (MgSO 4 ), filtered and solvent removed. The crude product so obtained was purified by flash chromatography using 5% ethylacetate in hexane. The yield of the pure viscous oil was 92%.
CIMS: 515 (M+l)
Other compounds which were prepared similarly as described in Example 3 are as follows:
1. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-dodecyl-α-D-lyxofuranoside
2. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-(N',N'-dimethylamino-n-propyl)-α-D-lyxofuranoside
3. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-N-ethylpyrrolidinyl-α-D-lyxofuranoside
4. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylpiperidinyl-α-D-lyxofuranoside
5. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-N'-ethylmorpholinyl-α-D-lyxofuranoside
6. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-hexamethyleneiminoethyl-α-D-lyxofuranoside
EXAMPLE 4
Preparation of Phenylpropyl 2,3-0-(1-methylethylidene)-5-p-toluenesulfonyl-α-D-lyxofuranoside
To a stirred solution of phenylpropyl 2,3-0-1-methylethylidene)-α-D-lyxofuranoside (33.8 g; 0.1 mol) in dry pyridine (100 ml) was added dropwise a solution of p-toluenesulfonyl chloride (22.8 g; 0.12 mol) in dry pyridine (150 ml), over a period of 20 minutes, at 0°-10° C. The progress of the reaction was monitored by tlc. After 5 hours the pyridine was removed under diminished pressure and the residue extracted with ethylacetate (400 ml), washed with a saturated solution of sodium bicarbonate (2×50 ml), brine (2×50 ml), and water (100 ml) . The organic layer was dried over MSO 4 , filtered and solvent removed. The residue on cooling and scratching with a small amount of hexane afforded a white crystalline material in 92% yield. It was recrystallized from ether-hexane of m.p 72-73 ° C.
CIMS: 463 (M+l).
The following tosylates were also prepared similarly as described in Example 4:
1. n-Dodecyl 2,3-0-(1-methylethylidene)-5-p-toluenesulfonyl-α-Dlyxofuranoside
2. n-Nonyloxypropyl 2,3-0-(1-methylethylidene)-5-p-toluenesulfonyl-α-D-lyxofuranoside
EXAMPLE 5
Preparation of Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-pyrrolidinyl-α-D-lyxofuranoside
To a stirred solution of phenylpropyl 2,3-0-(1-methylethylidene)-5-0-p-toluenesulfonyl-α-D-lyxofuranoside (5 g) in anhydrous DMF was added pyrrolidine (5 ml) and the mixture heated at 80°-90° C. for 4 hours. DMF was then removed under diminished pressure and the residue dissolved in ethylacetate (100 ml), washed with NaHCO 3 solution (1×10 ml) and brine (1×10 ml). The ethylacetate layer was dried over MgSO 4 , filtered and solvent removed. The residue so obtained was purified by column chromatography using 30% ethylacetate in hexane. The yield of the pure product was 89%
The following compounds were prepared similarly as explained in Example 5 by reacting phenylpropyl 2,3-0-(1-methylethylidene)-5-0-p-toluenesulfonyl-α-D-lyxofuranoside with a suitable primary or secondary amines:
1. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-morpholinyl-α-D-lyxofuranoside
2. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-hexamethyleneimino-α-D-lyxofuranoside
3. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoheptyl-α-D-lyxofuranoside
4. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpyrrolidinyl-α-D-lyxofuranoside
5. n-Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminopropylpyrrolidinyl-α-D-lyxofuranoside
6. Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpiperidinyl-α-D-lyxofuranoside
Phenylpropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylmorpholinyl-α-D-lyxofuranoside
EXAMPLE 6
Preparation of n-nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-pyrrolidinyl-α-D-lyxofuranoside
To a stirred solution of n-nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-p-toluenesulfonyl-α-D-lyxofuranoside (5 g) in anhydrous DMF was added pyrrolidine (5 ml) and the mixture heated at 80°-90° C. for 4 hours. DMF was then removed under diminished pressure and the residue dissolved in ethylacetate (100 ml), washed with NaHCO 3 solution (1×10 ml) and brine (1×10 ml). The ethylacetate layer was dried over MgSO 4 , filtered and solvent removed. The residue so obtained was purified by column chromatography using 30% ethylacetate in hexane. The yield of the pure product was 94%.
CIMS: 428 (M+l)
The following compounds were prepared similarly as explained in Example 5 by reacting n-nonyloxypropyl 2,3-0-(1-methylethylidene)-5-0-p-toluenesulfonyl-α-D-lyxofuranoside with a suitable primary or secondary amines:
1. n-Nonoyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-pyrrolidinyl-α-D-lyxofuranoside
2. n-Nonoyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-piperidinyl-α-D-lyxofuranoside
3. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-morphilinyl-α-D-lyxofuranoside
4. n-Nonyloxypropyl 5-deoxy 2,3-0-(1-methylethylidene)-5-aminoheptyl-α-D-lyxofuranoside
5. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpiperidinyl-α-D-lyxofuranoside
6. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylmorpholinyl-α-D-lyxofuranoside
7. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-hexamethyleneiminoethyl-α-D-lyxofuranoside
8. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminoethylpyrrolidinyl-α-D-lyxofuranoside
9. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-aminopropylpyrrolidinyl-α-D-lyxofuranoside
EXAMPLE 7
Preparation of n-Dodecyl 5-deoxy-2,3-0-(1-methylethylidene)-5-ethylpyrrolidinyl-α-D-lyxofuranoside
To a stirred solution of n-dodecyl 2,3-0-(1-methylethlidene)-5-0-ptoluenesulfonyl-α-D-lyxofuranoside (5 g) in anhydrous DMF was added 1-(2-aminoethyl) pyrrolidine 5 ml and mixture heated at 80°-90° C. for 4 hours. DMF was then removed under diminished pressure and the residue dissolved in ethylacetate (100 ml), washed with NaHCO 3 solution (1×10 ml) and brine (1×10 ml). The ethylacetate layer was dried over MgSO 4 , filtered and solvent removed. The residue so obtained was purified by column chromatography using 30% ethylacetate in hexane. The yield of the pure product was 88%.
CIMS: 455 (M+l)
EXAMPLE 8
Preparation of n-nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-S-2'-ethylpyrrolidinyl-α-D-lyxofuranoside
Step 1 n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethlidene)-5-thio-α-Dlyxofuranoside
To a stirred solution of n-nonyloxypropyl 2,3-0-(1-methylethylidene)-5-p-toluenesulfonyl-α-D-lyxofuranoside (as obtained in example 4) (10 g) in methanol (150 ml) was added NaSH.XH 2 O (10 g) and the mixture refluxed for 3 hours. Solvent was then removed using rotary evaporator and the residue extracted with ethyl acetate (150 ml), washed well with water (3×50 ml), sodium bicarbonate solution (2×50 ml), the organic layer dried (MgSO 4 ), filtered, and solvent removed. The residue so obtained was purified using flash chromatography and eluting with 5% ethyl acetate in hexane. The yield of the pure product was 78%.
CIMS: 391 (M+l).
Step 2 n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-S-2'ethylpyrrolidinvl-α-D-lyxofuranoside
Sodium hydride (60%, 0.4 g) was made free of oil by washing with hexane and added dry DMSO (20 ml). To this stirred solution was added a solution of n-nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-thio-α-D-lyxofuranoside (3.90 g; 0.01 mol) in DMSO (10 ml), dropwise, over a period of 10 minutes at room temperature. The reaction was stirred at -the same temperature for 30 minutes. 1-(2-chloroethyl)pyrrolidine (1.59 g; 0.012 mol) was then added dropwise over a period of ten minutes and the mixture stirred for another 3 hours. The reaction mixture was poured into ice cold water (200 ml) and extracted with ether (3×50 ml). The combined ether extract was washed once with water (20 ml), ether layer dried (MgSO 4 ), filtered and solvent removed. The crude product so obtained was purified by flash chromatography using 15% ethylacetate in hexane. The yield of the pure viscous oil was 81%.
CIMS: 488 (M+l)
Other compounds which were prepared similarly are:
1. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-S-n-decyl-α-D-lyxofuranoside
2. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-S-ethylmorpholinyl-α-D-lyxofuranoside
3. n-Nonyloxypropyl 5-deoxy-2,3-0-(1-methylethylidene)-5-S-ethylpiperidinyl-α-D-lyxofuranoside
PHARMACOLOGICAL ACTIVITY
The compounds of the present invention have demonstrated immunomodulatory and anti-inflammatory effects in biological assays. Various standard in vitro assays have been performed on most of the compounds of the present invention to ascertain immunomodulatory and anti-proliferative activities. These include:
i Mixed lymphocyte response (MLR).
ii BUD-8 human cell line fibroblast proliferation assay.
iii Concanavalin A assay (the mouse spleen cell mitogen induced blastogenesis).
The MLR assay measures the effects of a study compound on the activation and antigen presentation of T-lymphocytes, therefore determining immunomodulatory properties. The mouse spleen cell mitogen-induced blastogenesis and the BUD-8 human fibroblast proliferation assays measure the effects of the compounds of the present invention on cellular proliferation of cells involved in the pathogenesis of autoimmune diseases. These two assays are appropriate as screens to ascertain anti-inflammatory and/or autoimmune diseases.
The MLR is a classical assay used to measure T cell function by studying the proliferation response of T cells which are activated in vitro by genetically disparate stimulator cells. This is accomplished by co-culturing spleen cells from two different strains of mice. Splenic T cell proliferation occurs as a result of cellular activation signals generated by the ongoing cellular interactions.
In performing MLR assays, BALB/CBYJ mice were euthanized by cervical dislocation and their spleens removed. Single cell suspensions were prepared in culture medium (RPMI-1640 with hepes supplemented with 10% calf serum, 2 mM glutamine, 500 units penicillin/streptomycin and 4×10 -5 M 2-mercaptoethanol) using a Teflon pestle. The cells were centrifuged at 1500 RPM and the pellets resuspended in ACT (0.15 M Tris, 0.14 M ammonium chloride, pH 7.2 ) in order to lyse the red blood cells. After a 5 minutes incubation at 37° C. waterbath, the cells were washed and resuspended in culture medium. The splenic lymphocytes were counted. C57BL/6J spleen cells, which were used as stimulator cells, were prepared in the same way. The stimulator cells were treated with 50 μm/ml of mitomycin C for 20 minutes at 37° C., then washed five times in culture medium. The proliferative response were measured by culturing 5×105 responder spleen cells with 5×10 5 stimulator cells in 96-well microtiter plates in the presence or absence of test article or vehicle (DMSO). Syngeneic control cultures using mitomycin C treated normal BALB/C spleen cells as the stimulator cells were also run. All cultures were run in triplicate.
Solutions of compounds of the present invention in DMSO were prepared at a stock concentration of 300 mM. Solutions were made in a culture medium to a concentration of 1, 10, 30, 100, and 300 μM. The vehicle DMSO was used as a negative control.
After incubation for 5 days at 37° C. with 5% carbon dioxide, the amount of cell proliferation was measured by adding 20 μl of MTT (10 mg/ml in PBS) (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) to each well. plates were incubated for 4 hours at 37° C., after which 180 μl of supernatant was removed and 180 μl of 10% SDS in PBS was added. After an overnight incubation, the optical density (OD) of each well was read on a Molecular Devices microplate reader at 570-650 nm.
The results were determined by calculating the difference between the means of the allogeneic cultures and the means of the syngeneic cultures for each test compound concentration. Differences of the test article groups were compared to the difference of the control group. The percent change from the control was determined and an IC 50 estimated. The criteria used to establish activity levels were:
Estimated I 50
Inactive: >300 μM
Weak: >100 but<300 μM
Moderate: >30 but<100 μM
Strong: <30 μM
Sixteen (16) novel compounds were assayed for their ability to modulate a Mixed Lymphocyte Response in vitro. The test compounds were added to MLR cultures to give final concentrations of 1, 10, 30, 100, and 300 μm. The responses observed in the test article treated wells were compared to the control wells. DMSO did not appear to have any effect on the response. The results for the test compounds are shown in Table 1. Based on the estimated IC 50 all the test compounds were strong inhibitors of the MLR.
A second assay was conducted to demonstrate inhibitory activity of the compounds of the present invention to the in vitro proliferation of human skin cells in tissue culture. The skin cell fibroblast line, BUD-8, was originally derived from the normal skin of a 56 year old white female and can now be obtained from the American Type Culture Collection, Rockville, Md. The concentration of the compounds which were used in this assay were: 1, 10, 30, 100, and 300 μM. The vehicle was used as the negative control. Test compounds were prepared in DMSO at a stock concentration of 300 μM. Appropriate dilutions were made in culture medium.
In this assay BUD-8 cells were collected, counted, and diluted to 2×104 cells/ml. 0.1 ml was plated per well to give 2×10 3 cells/well. The compounds of the present invention were diluted in culture medium to the appropriate concentrations. Aliquotes of 100 μl were distributed to triplicate wells. Control wells with vehicle and wells with media were also run. After a three day incubation at 37° C. with 5% carbon dioxide, proliferation was measured by adding 20 μl of MTT (10 mg/ml in PBS) (3-[4,5-dimethyl thiazol-2-yl]-2,5diphenyl-tetrazolium bromide) to each well. Plates were incubated for 4 hours at 37° C., after which 180 μl of 10% SDS in PBS were added. After an overnight incubation, the optical density (OD) of each well was read using a Molecular Devices microplate reader at 570-650 nm.
Duplicate cultures were also set up to measure viability. After 3 days of incubation, supernatants were assayed for lactate dehydrogenase (LDH) activity to determine the viability of the cells, which is an indication of the toxicity of the test article on the BUD-8 cells. 0.1 ml of supernatent was mixed with 0.1 ml of the LDH substrate mixture which contains 5.4×10-2 M L(+) lactate, 6.6×10 -4 M 2-p-iodophenyl-3-p-nitrophenyl tetrazolium chloride, 2.8×10 -4 M phenazine methosulfate, 1.3×10 -3 M AND, and 0.2 M Tris buffer. PH 8.2. Plates were read immediately for 5 minutes at 490 nm using a Molecular Devices microplate reader.
The mean for each test article treated group was determined and compared to the mean of the control group. The percent change from the control was calculated, and the IC 50 estimated. The criteria used to establish activity levels were:
Estimated IC 50
Inactive: ≧300 μM
Weak: ≧100 but<300 μM
Moderate: ≧30 but<100 μM
Strong: <30 μM
Sixteen (16) test articles were assayed for their ability to inhibit fibroblast proliferation. The test article were added to BUD-8 cell cultures to give final concentrations of 1, 10, 30, 100, and 300 μM. The proliferation observed in the test article treated wells were compared to the DMSO control wells. The results of the test articles are shown in Table 1.
A third assay was conducted to demonstrate the ability of the compounds of the present invention to modulate T-lymphocyte activity. It is known that the induction and maintenance of most inflammatory diseases are typically due to the unrestricted activity of T-lymphocytes. Therefore, it is advantageous to identify compounds which are modulators of T-lymphocyte activity for eventual use in the regulation of inflammatory diseases, including acquired immune deficiency syndrome, psoriasis, systemic lupus, erythromatosus, and rheumatoid arthritis.
A simple method is used to screen compounds for their ability to modulate T-lymphocyte activity which comprises assessing the capacity of the compounds to alter the activation of murine spleen cells in response to T-lymphocyte mitogen activators, such as Conconavalin-A (Con-A). The method used to measure the effects of the compounds of the present invention on the blastogenic response of spleen cells to the T-lymphocyte mitogen (Con-A) is as follows:
The response of a mouse spleen cells to the T cell mitogen ConA is a classical assay. In this assay, mice were euthanized by cervical dislocation and their spleens removed surgically. A single cell suspension of the spleens was prepared in culture medium (RPMI-1640 with hepes, supplemented with 10% calf serum, 2 mM glutamine, 500 units penicillin/streptomycin, and 4×10 -5 M 2-mercaptoethanol) using a Teflon pestle. The cells were centrifuged at 1500 RPM and the pellets resuspended in ACT (0.15 M Tris, 0.14 M Ammonium chloride, pH 7.2) in order to lyse the red blood cells. After a five minutes incubation in 37° C. waterbath, the cells were washed and resuspended in culture medium. The splenic lymphocytes were counted using an electronic Coulter Counter and diluted to 5.0×10 6 cells/mi.
The test articles were diluted in culture medium to the appropriate concentrations. Aliquots 100 μl were distributed to triplicate wells in a 96-well microtiter plate. 50 μl of lymphocytes (2.5×10 5 cells) were added to each well. Control wells with vehicle and wells with media were also run. Plates were incubated for one hour at 37° C. 50 μl of Con-A (5 μl/ml) were then added to the wells to result in a final concentration of 1.25 μg/ml. After incubation at 37° C. with 5% carbon dioxide for 3 days, proliferation was measured by adding 20 μl of MTT (10 mg/mlin PBS) [3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazoliumbromidel to each well. Plates were incubated for 4 hours at 37° C., after which 180 μl of 10% SDS in PBS were added. After an overnight incubation, the optical density (OD) of each well was read using a Molecular Devices microplate reader at 570-650 nm.
Duplicate cultures without Con-A were also set up. After 3 days of incubation, supernatants were assayed for lactate dehydrogenase activity to determine the viability of the cells, which is an indication of the toxicity of the test article on the splenic lymphocytes. 0.1 ml of supernatant was mixed with 0.1 ml of the LDH substrate mixture which contains 5.4×10 -2 M L(+) lactate, 6.6×10-4 M 2-p-iodophenyl-3-p-nitrophenyl tetrazolium chloride, 2.8×10 -4 M phenazine methosulfate, 1.3×10 -3 M AND, and 0.2 M Tris buffer, pH 8.2. Plates were read immediately for 5 minutes at 490 nm using a Molecular Devices microplate reader.
The mean for each test article treated group was determined and compared to the mean of the control group. The percent change from the control was calculated, and the IC 50 was estimated.
The criteria used to establish activity levels were:
Estimated IC 50
Inactive: ≧300 μM
Weak: ≧100 but<300 μM
Moderate: ≧30 but<100 μM
Strong: <30 μM
Sixteen (16) test articles were assayed for their ability to modulate a Con-A response in vitro. The test article were added to Con-A cultures to give a final concentrations of 1, 10, 30, 100, and 300 μM. The response observed in the test article treated wells were compared to the control wells. DMSO alone had little effect on the response. The results for the test articles are shown in Table 1.
The compounds of the present invention were also tested against various tumor cell lines, derived from seven cancer types. These include leukemia, melanoma, lung cancer, colon cancer, renal cancer, ovarian cancer, and brain cancer. Most of the compounds have shown significant activity in various screens, particularly against colon cancer and melanoma. The results of the test articles Average GIy 50 ) are shown in Table 1.
The compounds of the present invention have demonstrated significant immunomodulatory and anti-proliferative properties when tested in the aforementioned in vitro assays. The concentration tested ranged from 1 μM to 300 μM, with the most efficacious activities defined as one-half the maximal inhibitory concentrations (IC 50 ) or (GI 50 ) of 30 μM of less.
TABLE 1______________________________________ MLR Con A FibroblastCompound # IC.sub.50 (μm) IC.sub.50 (μm) IC.sub.50 (μm) GI (μM)______________________________________V. <1 2.9 28 -5.25VI. 0.5 2.7 >100 NAX. <1 55 299 -4.04XVI. <1 3.5 58 -5.29XXIV. 0.85 2.5 16 NAXXV. 12 25 200 -4.02XXIX. 1.5 5 20 -4.49______________________________________
While the present invention has been described in terms of its specific embodiments, certain modifications and equivalents will be apparent to those skilled in art and are intended to be included within the scope of the present invention, which is to be limited only by scope of the appended claims.
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 appended claims, the invention may be practiced otherwise than as specifically described herein.
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Derivatives of disubstituted and deoxydisubstituted α-D-lyxofuranosides and intermediates for preparing these derivatives are described. These compounds exhibit significant antiinflammatory and anti-proliferative activity and are useful for treating inflammatory and/or autoimmune disorders such as psoriasis, asthma, atopic dermatitis, rheumatoid arthritis, osteoarthritis, scleroderma, systemic lupus erythematosus, and cancer (particularly melanoma and colon cancer).
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CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a U.S. national stage application of international app. No. PCT/FI2005/050006, filed Jan. 14, 2005, the disclosure of which is incorporated by reference herein, and claims priority on Finnish App. No. 20040049, filed Jan. 15, 2004, and also claims priority on Finnish App. No. 20045148, filed Apr. 23, 2004.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] The invention relates to an arrangement in a paper machine or similar, which includes a press section equipped with one or more press nips and a dryer section comprising a web-supporting closed web transfer, a vertical impingement dryer and one or more subsequent cylinder dryer groups. The invention relates particularly to impingement unit applications blowing directly to the web.
[0004] With increasing paper machine speeds the runnability of the machine becomes very critical unless measures are taken at the same time for improving runnability. Runnability can be improved up to a certain limit by maintaining a sufficient web tension by means of a speed difference between successive stages. Even this method will become exhausted at the stage when the paper quality starts to deteriorate.
[0005] Rising paper machine speeds have led to a tendency to preferably use a closed transfer from the press section to the dryer section, and, particularly in a multicylinder dryer, the single fabric run arrangement, as far as possible, even to the end of the cylinder dryer. These are used to get rid of fluttering and similar phenomena, which occur in the free web transfer. From the center roll of the press section the paper web can however be picked up to the dryer section using an open transfer.
[0006] A paper machine dryer section using merely a multicylinder dryer becomes fairly long at high, 30 m/s to 40 m/s, speeds. According to Finnish patent 102623 (WO 97/130131) and Finnish patent application 20002429, impingement dryers are used to replace dryer cylinders, particularly at the beginning of the dryer section, in which full steam pressure cannot be used in dryer cylinders or steam supply of the first cylinder is sometimes even completely closed. A wet paper web attaches to a hot cylinder surface due to which it is necessary to use a lower cylinder surface temperature, whereat drying capacity is lost.
[0007] In an impingement drying unit, in which impingement takes place directly against the paper web and not through the fabric, it is possible to use fairly high blowing temperatures, 250° C. to 700° C., and thus achieve a very efficient heating effect. The paper web is set to travel on top of a support fabric, which is supported in the blowing area by a set of rolls either in a straight run or with a large curvature radius. Suction/blow boxes are placed between the rolls for keeping the paper web against the support fabric.
[0008] According to patent application 20002429 (WO 02/36880), it is possible to spare the machine-directional length by using one or more vertical impingement units. The support fabric has in the vertical direction a notably long loop compared to its machine-directional dimension, at least in the dryer cylinder line. The support fabric remains under the paper web as regards blowing and consequently is not subjected to heat. On both sides of the loop generally there are impingement units, both of which thus have a drying length of even several meters. Keeping the paper web attached to the support fabric is ensured by using internal suction devices, which direct the suction effect to the paper web from inside via the support fabric. The side profile of the impingement surface is straight, slightly curved, possibly variably curved, in a shape of a broken line or a combination of these.
[0009] The impingement unit comprises a web arrangement that provides support for the paper web and a blowing chamber, which has a perforation on its web side flank for distributing air or other hot gas onto the blowing surface.
[0010] Space saving is realized also in such a case when the orientation of the unit deviates even remarkably from the vertical, as it will in any case be located in a space below or above the paper machine. On the other hand, a vertical construction has the advantage that the earth's gravity cannot disturb the attachment of the fabric to the support surface.
[0011] In a closed transfer, a great number of fabric loops composed of support fabrics are needed. As the number and total length of these increase, web break risks generally increase. Therefore, the optimization of their number and lengths is aimed at.
[0012] Although the above-mentioned known impingement solutions have provided improvements compared to the prior art technique related to runnability at high speeds and the machine size in the longitudinal direction, the situation has not been completely satisfactory. A simpler, yet a reliable concept is still required.
[0013] The bulk, in units of cm 3 /g, of paper is a significant quality factor for many paper grades. However, good bulk is in contradiction with the maximum press section dewatering, because achieving a high dry content after the press requires high nip pressures.
[0014] According to patent 102623, an impingement unit is located after the press section before the first dryer cylinder. Units blowing through a fabric according to the patent suffer from the blast air temperature limit, since the present drying fabrics cannot be stressed with blast air or steam hotter than 200° C. The construction becomes, however, relatively long, and the machine longitudinal saving is not notably achieved with simple solutions. With vertical impingement units according to patent application 20002429, remarkable savings are achieved much faster in the machine length. With the proposed solutions using vertical impingement units, the runnability is not better than today after the press section.
SUMMARY OF THE INVENTION
[0015] The object of the invention is to provide an improved arrangement in a paper machine, in which a vertical impingement unit is used. With the invention, elimination or at least minimization of the above-mentioned drawbacks is aimed at.
[0016] Impingement dryers are best used to replace exactly the first cylinder dryers, as their capacity remains rather poor due to a reduced steam pressure. Instead, there are no similar restrictions for straight impingement, and extraordinarily high temperatures can be used in it when blowing directly to the web. An efficient vertical impingement dryer requires however, for ensuring runnability, a pre-impingement dryer for drying the opposite side of the paper web at least to a certain extent and by running the moisture gradient growing towards the bottom surface. At the same time, the preceding efficient web heating enables the full drying capacity of a vertical unit. Preferably a vertical impingement dryer is unilaterally drying and directed to the same side as the first cylinder dryer such that full or almost full steam pressures can be applied starting from the first cylinder, that is, high drying temperatures on the cylinder surface without the risk of sticking.
[0017] Here “horizontal” and “vertical” should be understood widely as comprising a deviation of even 45°. In addition, the impingement surface can be curved or a polygon imitating a curved shape or a combination of these.
[0018] In another embodiment the top surface of the impingement chamber of the vertical impingement unit forms the pulper chute.
[0019] In a third embodiment the vertical impingement unit has several support rolls on top of each other, supporting the support fabric from the inside of the fabric loop. Between these rolls, there are arranged suction boxes in the web direction and in the vicinity of the fabric surface in a method known as such.
[0020] In a fourth embodiment, a pre-impingement dryer is placed over the section of the press transfer belt and the paper web is transferred therefrom directly to the fabric loop of the vertical impingement dryer. This is used to replace even two separate transfer fabric loops. This type of combination is particularly compact.
[0021] Pre-impingement follows immediately after the press is already on the press fabric or on the transfer or dryer fabric after the press. The rest of the machine design determines how near to the press, i.e. how compactly pre-impingement can be carried out.
[0022] The relative distances between the pre-impingement dryer, generally horizontal, and the vertical impingement dryer as well as the first dryer cylinder following those, are restricted by the fact that it is not desired that the web cools down excessively in the unheated section. In order to gain benefit from pre-impingement, the web must not cool down between the air blows, but the cooling effect of normal evaporation is still advantageous for the entity with dimensions given later. On the other hand, the web surface temperature should deviate less than 15° C., most preferably less than 8° C. from the dryer cylinder surface temperature, normally approximately 80° C. in a paper machine, to avoid harmful sticking of fibers etc. Normally it is allowed that this interval be 4 meters at the maximum, preferably less than 2 meters. In a compact construction, pre-impingement starts at a distance less than 2 meters, most preferably less than 1 meter from the press.
[0023] Higher steam pressures are used in board machines, thus the cylinder surface temperature can be as high as 130° C., whereat the deviations can also be greater. In addition, the cylinder may have a temperature profile, in which the edges are warmer than the rest of the cylinder, which can also be taken into account by profiling impingement and/or the steambox.
[0024] The invention can be fully utilized when a short pre-impingement dryer and a vertical impingement dryer are compactly installed between the press and the first cylinder group. Here a vertical impingement dryer equipped with two opposite units can be adapted to a short machine length, and the first dryer cylinder immediately following it can be adapted to essentially full steam pressures. More than one vertical impingement dryers cannot be compactly installed one after another in the machine direction, because the opposite hoods must be installed relatively far from each other. Instead, in addition to the underneath unit, it is possible to have opposite impingement units above the machine, as the arrangement does not increase the machine length.
[0025] The invention is described below in more detail by making reference to the enclosed drawings, which illustrate some of the embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 illustrates an arrangement of a paper machine using impingement after the press.
[0027] FIG. 2 illustrates another arrangement according to the invention.
[0028] FIG. 3 a illustrates a third arrangement according to the invention.
[0029] FIG. 3 b illustrates another embodiment using a steambox.
[0030] FIG. 4 is a diagram showing the interdependencies between bulk after press and dry matter for some paper grades.
[0031] FIG. 5 is a diagram showing an embodiment of the second group of the invention.
[0032] FIG. 6 is a diagram showing the second embodiment of the second group of the invention.
[0033] FIG. 7 is a diagram showing the third embodiment of the second group of the invention.
[0034] FIG. 8 is a diagram showing the fourth embodiment of the second group of the invention.
[0035] FIG. 9 is a diagram showing the fifth embodiment of the second group of the invention.
[0036] FIG. 10 is a diagram showing the sixth embodiment of the second group of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] FIGS. 1-4 depict a paper machine, in which shown are the press section 11 and some of the first sections of the dryer section, namely the pre-impingement dryer 20 , vertical impingement dryer 21 and a beginning of the cylinder group 14 . The first dryer cylinder is indicated with reference number 14 . 1 .
[0038] The various parts of the arrangement, namely the press section, impingement dryers and cylinder dryers are known for their basic design from e.g. the above-mentioned patent publications.
[0039] The twin-nip press 11 has nips 13 . 1 and 13 . 2 . The paper web is picked up in a known manner to the press section 11 with the pick-up roll 15 . 1 and it is transferred through the nips by means of the press felts 12 and the transfer belt 28 . As regards this invention, the design of the press section can vary to a great extent. Particularly essential is however that after the press section 11 , or integrated to its end part, there is a horizontal or pre-impingement dryer 20 , which in FIGS. 1 , and 3 a uses the dryer fabric 17 , against which the blowing unit 20 . 1 is placed. According to the prior art technique, in the center roll solution there is an open interval in the transfer from the press to drying, and with this embodiment, too, it is possible, irrespective of the press, to arrange an open/openable interval if required when shifting from impingement drying to cylinder drying.
[0040] Referring to FIGS. 1 and 3 a , the paper web is picked up from the transfer belt 28 with the transfer suction roll 15 . 3 and led to the transfer fabric 16 , which transports it to the dryer fabric 17 of the horizontal impingement dryer 20 by means of the transfer suction roll 15 . 4 .
[0041] The paper web travels on top of the dryer fabric 17 from below the blowing unit 20 . 1 , whereat it is subjected to a strong heating effect. In a short blowing zone drying occurs relatively little, but the web warms up and its top surface layer dries slightly. This is however significant as regards the runnability. At the same time, the moisture gradient in the thickness direction of the web becomes strongly growing towards the bottom surface. Inside the dryer fabric loop 17 there are vacuum boxes 20 . 3 and support rolls 20 . 2 for keeping the web attached to the said fabric 17 .
[0042] After the horizontal impingement dryer 20 , the paper web is transferred from the dryer fabric 17 after the vacuum roll 17 . 1 onto the dryer fabric 14 . 2 of the first dryer cylinder group 14 . This same dryer fabric 14 . 2 is also used by the vertical impingement dryer 21 . In a method known as such, the paper web is transferred to the dryer fabric 14 . 2 by means of the topmost roll 21 . 3 , functioning as a vacuum roll, suction roll or VAC roll, of the vertical impingement dryer 21 . The roll 21 . 3 has a fabric wrap within an area of 3° to 10°. The dryer fabric 14 . 2 is supported in the straight section forming the blowing surface by several small support rolls 21 . 5 , between which there are blow boxes 21 . 6 providing aspiration for creating a vacuum on the bottom surface of the transfer fabric, i.e. on the opposite surface of the paper web, whereat the paper web becomes aspirated against the transfer fabric 14 . 2 .
[0043] The vertical impingement dryer 21 has two opposite impingement units 21 . 1 and 21 . 2 , which are set on both sides of a narrow dryer fabric loop as seen from the side. The impingement surfaces are mainly delimited between the above-located roll 21 . 3 and the turning suction roll 21 . 4 , although their hoods can extend to the curved section. Between these, on both surfaces, more precisely inside the fabric loop, there are support rolls 21 . 5 and blow boxes 21 . 6 , such as is set forth for example in patent application 20002429. The support rolls can be grooved rolls, VAC rolls or suction rolls.
[0044] The center line of the vertical impingement dryer 21 deviates from the perpendicular by a maximum of 35°, such that it still saves machine-directional space. The pre-impingement predryer may deviate as much as 60° from the horizontal.
[0045] The temperature of the blast gas in the impingement dryers 20 , 21 is preferably in a range of 200° C. to 700° C., most preferably in a range of 250° C. to 400° C. The steam of the steambox 16 . 1 used for the preheating of impingement drying is preferably slightly, normally 7° C., superheated and condenses on contacting the web, but not yet in the steambox. The web temperature can also be influenced by the impingement air moisture, air blow recirculation.
[0046] At the doctor of the first dryer cylinder 14 . 1 there is designed a web knock-down for web break situations. In this case the broke is conveyed to the pulper 30 along the upper flank 21 . 21 of the blowing unit 21 . 2 hood. In tail threading the web is run at full width to the pulper through the press and the impingement units. For tail threading, there is a tail squirt (not shown) located in the vicinity of the cylinder 14 . 1 . In a center roll press, tail threading is carried out as a band over blowing units until to the said doctor.
[0047] In a normal situation the paper web travels with the dryer fabric 14 . 2 through the cylinder group to the subsequent group.
[0048] The impingement length of a horizontal impingement dryer is 50% at the maximum, most preferably 15% to 35% of the total web length of impingement. A greater pre-blowing length provides even drying in addition to preheating.
[0049] FIG. 2 shows a preferable modification of the arrangement according to the invention as compared to FIG. 1 . Functionally similar parts are referred to using the same reference numbers as above.
[0050] Here it has been possible to leave out two transfer fabric loops, as the horizontal impingement dryer 20 has been placed on the press transfer belt 28 . From the transfer belt 28 the paper web is transferred to the dryer fabric 19 of the vertical impingement dryer. In FIG. 2 it is separate, but it can as well be a part of the dryer fabric 14 . 2 of the first cylinder group as above.
[0051] The paper web transfer from the transfer belt 28 to the dryer fabric 19 takes place in a method known as such. The turning roll 28 . 1 takes the fabric loops together and the transfer suction roll 21 . 3 picks up the paper web onto its own dryer fabric 19 . When the vertical impingement dryer is equipped with a fabric loop of its own, an additional transfer point is provided in connection with the first cylinder, at which transfer point it is possible to use a speed difference for maintaining runnability. This has a particular importance when the dry content is lower, such as is set forth below.
[0052] Generally at a vertical impingement unit:
An own fabric loop is arranged when the subsequent web dry content is 48% to 54%, or A fabric loop common with the short, i.e. a maximum of 3 dryer cylinders, dryer cylinder group when the dry content after the blowing units is 52% to 57%, or A fabric loop common with the long, i.e. 4 or more cylinders, dryer cylinder group when the dry content after the blowing units is 56% to 65%.
[0056] It should be noted that for quality reasons, e.g. with a weak furnish/web or in an embodiment according to FIG. 2 , it is possible, if necessary, to use an own fabric loop also with a higher dry content, arranging thus one additional transfer point.
[0057] The arrangement of FIG. 3 a is for the main part similar as in FIG. 1 . The design of the impingement unit is however simplified such that inside the dryer fabric loop, between the auxiliary turning roll 21 . 4 and the vacuum roll 21 . 3 , support rolls 21 . 5 of the same size as these rolls are used, which are preferably vacuum rolls, being actually the same as the turning suction rolls of the dryer cylinder. The suction boxes between these are of the same type as above. Depicted with broken lines in this figure is also a possible steambox 16 . 1 , the use of which provides completely new possibilities in impingement. In this figure it is located below the web, but it would also be possible to replace the first impingement box completely with the steambox. The application possibilities of the steambox are discussed below. In one modification the support rolls 21 . 5 are larger than rolls 21 . 3 and 21 . 4 such that the fabric touches the rolls for a longer distance. This improves the suction effect, which enhances further the runnability.
[0058] The arrangement according to the invention can be used to improve the paper value for certain grades, in which the paper's bulk is significant. According to FIG. 4 , dry content and bulk after press correlate inversely in different paper grades. Instead of using high nip pressures of 1000 kN/m at the press, the nip pressures are reduced in the first and second nip to a range of 400 kN/m to 800 kN/m. With the invention, drying of 1% to 2% of dry matter is transferred from the press section to impingement such that the paper's bulk is maintained. The increase in dry content for the impingement stages is preferably 3% to 12% in total before the dryer cylinders, more precisely 400%±100%/basis weight, g/m 2 , where a large range of fluctuation compensates the effect of the paper machine speed on the dry content.
[0059] With the invention, runnability is maintained, although the draw difference between the press and the first cylinder is set below 2.9%, most preferably below 2.5%, irrespective of the fact that the web is dried with impingement blows and is possibly transferred from a fabric to another even more than once.
[0060] FIG. 3 b shows another steambox application, in which all impingement blows are on the same side of the paper web, because pre-impingement is carried out with steam. Reference numbering corresponds to the previous figures for applicable parts. Here installed on the fabric 14 . 2 of the first dryer group 14 there are also a steambox 16 . 1 , vertical, i.e. straight, impingement unit 20 . 1 and the impingement unit 21 of the vacuum roll, before the first dryer cylinder 14 . 1 . The paper web travels on the bottom surface of the fabric 14 . 2 , onto which it has been transferred with the transfer suction roll 14 . 3 . The steambox 16 . 1 efficiently increases the paper web temperature and consequently even a short impingement section dries the web surface on the cylinder side preventing it from attaching to the first dryer cylinder. By lowering the vacuum roll 14 . 4 , the impingement length can be increased in this embodiment, too, approaching thus the combination of preheating and vertical.
[0061] Differing from gas operated impingement, the steambox can be better located on the same side of the paper web as vertical impingement, because the heating effect provided by steam condensing is particularly strong compared to gas convection. The steambox is profiling already as such, but it can be further divided into accurately profiling compartments in the cross-machine direction. Although condensing brings water to the paper web, this is not a great drawback when using impingement, because the paper web surface can in any case be made drier than without it, allowing full pressures in the first dryer cylinder.
[0062] The following advantages are associated with the use of a steambox:
Known as such as a process and currently used at the press. The steambox creates a temperature profile and drying continues more intensive from warmer places in the dryer section. The phenomenon is intensified with the proposed arrangement. More accurate, precise and efficient moisture profile control, compared to the traditional steambox use at the press, because the web does not get wet again after profiling. Increased drying capacity, since the web temperature is raised by 20° C. to 30° C. before impingement. The moisture profile is controlled throughout the entire dryer section, as warmer places dry faster than the cold ones. Enables better optimization of press loads e.g., in solutions requiring bulk load reduction at press.
[0068] FIGS. 5-10 show embodiments of the second group of the invention and equal reference symbols are used for corresponding parts unless otherwise indicated.
[0069] In the embodiment according to FIG. 5 , the web 100 is led from the press section 110 , from the last press nip 105 thereof, which has been formed between rolls 112 , 113 , on the surface of the last fabric, most appropriately on the surface of a transfer belt or felt 111 , to the first transfer fabric 120 , to which the web 100 is transferred by means of the pick-up roll 121 . On the transfer fabric 120 the web transfer is supported by blow boxes 125 , which are most appropriately blow boxes of the type marketed by Metso Paper, Inc. with the trademark PressRun. Followed by this there is a tail squirt 126 or a similar element for cutting a web threading tail, which is followed by a roll 130 , with a movable position, which is most appropriately smooth and equipped with a doctor 131 . For the tail threading, the roll 130 with a movable position is lifted to the top position, as shown with broken lines in the figure. From the smooth roll 130 the web is doctored with the doctor 131 to the pulper 141 during tail threading. The web travel to the pulper is ensured by a guide plate 142 , and the chute 143 guides the web that has advanced any further to the pulper 141 in a disturbance/when required. The chute 143 can also be separate from the impingement hood 151 and comprises water showers for guiding the web to the pulper 141 . From the first transfer fabric 120 the web is led to a second transfer fabric 136 , onto which the web is transferred by means of the transfer suction roll 135 . This can be followed by an impingement drying unit 140 located above the web on the transfer fabric 136 . The guide and lead rolls of the first transfer fabric loop are indicated with reference number 122 . The guide and lead rolls of the second transfer fabric loop are indicated with reference number 138 . From the second transfer fabric 136 the web is led to vertical impingement drying, onto its dryer fabric 159 , with which the web is transferred via the transfer suction roll 155 . The guide and lead rolls of the dryer fabric loop 159 are indicated with reference number 154 . First the web travels essentially vertically downwards, whereat it is dried with the impingement unit 151 , after which the web travel direction is reversed at roll 153 , after which the web 100 travel is essentially vertically upwards, during which travel it is dried by means of air blows provided by the impingement unit 152 . After this the web is led on the dryer fabric 159 to cylinder drying, where the web 100 to be dried remains between the dryer fabric 159 and the heated cylinder surface 156 and the web 100 travel conforms to a normal single fabric run, whereat its travel is windingly turned with turning rolls or turning cylinders 157 . The transfer suction rolls can also be moved to the tail threading position for the duration of tail threading of the web. For the transfer suction rolls, this position is also the standard operating position, such that tail threading and normal operation differ as regards the vacuum levels of the transfer suction rolls in that generally the vacuum used during tail threading is higher.
[0070] Exemplifying embodiments of the invention shown in the following FIGS. 6-8 correspond to the exemplifying embodiment of FIG. 5 unless otherwise indicated.
[0071] In the embodiment shown in FIG. 6 the web travel is essentially lineal and this has been so arranged that the second transfer fabric 136 extends to the area of the first transfer fabric loop 120 providing for the web a bilateral support, which allows arranging the web travel as essentially lineal. In this embodiment the web is transferred to the transfer fabric 136 with the transfer suction roll 137 and further to the dryer fabric 159 of the impingement drying group with the transfer suction roll 155 . In this embodiment the first transfer fabric loop 120 is equipped with blow boxes 125 , which are used to guide the web travel.
[0072] In the embodiment shown in FIG. 7 , the roll with a movable position is located inside the first transfer fabric loop 120 and it is indicated with reference number 124 , as it simultaneously forms one of the guide and lead rolls of the transfer fabric loop during tail threading. Because this roll is movable, the transfer fabric loop is additionally provided with another roll 123 with an adjustable position for maintaining the tension of the transfer fabric loop 120 . In the embodiment shown in FIG. 7 the second transfer fabric loop 136 transports the web 100 only for a short distance mainly in the area of the transfer suction roll 137 and for a short section before the web 100 encounters the dryer fabric 159 of the impingement dryer group at the transfer suction roll 155 . The other roll 134 of the transfer fabric loop 136 is movable for its position, as is illustrated in the figure with an arrow and the transfer position marked with broken lines. Thus the transfer fabric loop 136 can be moved away from contact with the transfer suction roll 155 of the impingement drying group such that the web 100 can be led to the pulper via the chute 143 in a disturbance/when required.
[0073] In the embodiment shown in FIG. 8 the transfer fabric 120 is simultaneously the dryer fabric of the vertical group, which reduces the number of transfer points and thus the need of transfer suction rolls. The roll 133 is preferably a blow roll, and the suction box 158 can also make sure that the web 100 follows the fabric 120 in the downwardly fabric travel. In this way it is at the same time possible to increase the length of the impingement drying section. The roll 133 is preferably a blow roll, but by intensifying the vacuum device 158 it is possible to locate even a cylinder in this position, which however in a tail threading situation may be a slightly less advantageous alternative, because then it is necessary to controllably use the cylinder on the opposite side of the blow roll only over the width of the proceeding band. In case the roll 133 is a blow roll, it can be for example a warm blow roll, approximately 140° C. inside the roll, or the roll can be a grooved roll, the groove size of which is 1×1 mm and then its effect is intensified with the vacuum device 158 .
[0074] In the embodiments of FIGS. 6-8 impingement drying is carried out with steamboxes according to FIG. 3 b.
[0075] Referring to the embodiments of FIGS. 5-8 , the web dry content is raised in the dryer section of a paper machine to a sufficient value, being typically 50% to 65% of dry matter, even 70% of dry matter before dryer cylinders are used for drying. According to the invention the paper web is thus dried after the press section with impingement drying in a vertical impingement drying group before cylinder drying. According to the invention, in the method the paper web is led from the press section to the vertical impingement drying group from the last fabric of the press section, i.e. a transbelt or a felt, by means of at least one transfer fabric.
[0076] In connection with the invention, especially FIGS. 5-8 , arranged in connection with at least one transfer fabric used for leading the web from the press section to the first vertical impingement drying group of the dryer section, there is preferably a roll with a movable position or similar, for example, which for the duration of tail threading is moved to the tail threading position, most appropriately to the top position, and after tail threading to a position, in which it does not affect the web travel. The section of the web to be led from the movable roll to the pulper can be selected for example by moistening the roll over this desired width, thus the tail position in the roll continuing further in tail threading would be dry, and correspondingly it is possible to moisten the roll over the entire width when running down the entire wide web. Arranged in connection with the transfer fabric there are preferably blow boxes, providing a vacuum effect, by means of which the web is kept in the conveyance of the transfer fabric. According to one preferable additional feature of the invention, the first transfer fabric is followed by a second transfer fabric, which is located below the web and by means of which the web is led to the dryer fabric of the vertical impingement drying group.
[0077] According to one preferable embodiment of the invention, the web is led from the last press nip of the press section on the surface of the last fabric, most appropriately a transbelt or a felt, from which the web is transferred to the first transfer fabric. The web transfer is then followed by a tail squirt or other similar device for cutting a web threading tail. This is followed by a roll with a movable position, most appropriately a smooth roll, associated with a doctor. The web is run at full width from the pick-up roll of the first transfer fabric loop, i.e. from the roll that picks it up from the previous fabric, to the roll with a movable position, which has been moved to the tail threading position, to the top position, while the pick-up roll goes down and picks up the web from the last fabric of the press section. Because the transfer fabric covers a part of the roll with a movable position, the web follows the roll and arrives at the roll doctor, from where it slides down to the pulper. After this the concept includes a second transfer fabric, which is used to take the web to the dryer fabric of the vertical impingement drying group. The drying effect of the vertical impingement drying unit is such that the web dry content can be raised to a level of 50% to 65% of dry matter, most appropriately 55% to 63% of dry matter, before leading the web to cylinder drying. The roll with a movable position is in the top position while the web threading tail is transported over the vertical impingement unit, and once the web is widened, the roll with a movable position is lowered to a position unaffecting the web travel, to the bottom position such that it does not create a problem point as regards the opening gap, as in this case an opening gap, in which a vacuum complicating runnability that is harmful for the web travel would otherwise be created, is not formed. Located inside the loop of the first transfer fabric there are blow boxes, most appropriately boxes of the type marketed by Metso Paper, Inc. with the trademark PressRun, for ensuring the web travel.
[0078] In the exemplifying embodiment of the invention shown in FIG. 9 , the web 200 is led from the press section 202 , from the last nip 205 thereof, with the bottom fabric 211 of the press to position 207 , in which the web 200 travel takes a steep curve downwards at the roll 212 to vertical impingement drying 220 , in which the web 200 is dried, in the downwardly section thereof, by means of drying air blows provided by the impingement drying unit 221 . The lead and guide rolls of the fabric 211 are indicated with reference number 223 . Located in the section between the last press nip 205 and position 207 there is the impingement drying unit 215 for pre-impingement, which preferably provides more drying blow length for impingement drying. According to this embodiment, too, when using the last press section fabric 211 , savings are made in fabric arrangements and the related roll arrangements. After the downwardly impingement drying 220 , the web 200 is led onto the dryer fabric 232 of the first dryer group 209 , on which the web 200 , after the horizontal section, in which the web 200 is supported by vacuum boxes 233 , is first turned by means of roll 235 to vertical upwardly impingement drying 230 , whereat the web 200 is dried with drying air blows provided with the impingement drying unit 236 , after which the web 200 is taken to cylinder drying applying the single fabric run arrangement, in which the web 200 windingly travels on the dryer cylinders 243 and the suction or turning cylinder 242 . The runnability of the web 200 is intensified by the vacuum components 241 . In a knock-down situation, such as tail threading and web break, it is possible to lead the web 200 from the cylinder drying section 209 to the pulper 250 at one of its first dryer cylinders. The pulper chute is indicated with reference number 259 .
[0079] In the embodiment of the invention shown in FIG. 10 , the web 200 is led from the last press nip 205 of the press section on the surface of the last bottom fabric 211 of the press section, where the press nip 205 is first followed by pre-impingement in the horizontal impingement drying unit 215 , after which in position 207 the web 200 takes a curve downwards at roll 212 on fabric 211 , from which it is picked up onto the dryer fabric 232 of the first dryer group 209 with the transfer suction roll 238 and the web 200 is led to vertical impingement drying 220 , in which the web 200 is dried in an essentially downwardly section by means of drying air blows provided by the impingement drying unit 221 . Keeping the web 200 attached to the fabric 232 surface is facilitated by the vacuum boxes 234 . The web 200 travel is turned to an essentially upwardly direction at roll 235 , in which upwardly travel the web 200 is dried with vertical impingement drying 230 by means of drying air blows provided by the impingement drying unit 236 , after which the web 200 is led to cylinder drying applying the single fabric run arrangement. The pulper is indicated with reference number 250 and the pulper chute with reference number 259 . In a knock-down situation the web 200 is led to the pulper 250 from one of its first cylinders of its first dryer group. This embodiment of the invention enables locating another pulper 255 after the press section 202 before vertical impingement drying 220 .
[0080] In one simulation the paper grade used was fine paper, 78 g/m 2 , a pre-impingement length of 6 m, and the paper temperature coming from the press section has been assumed to be 45° C. In this case preblowing warms up the web to 74° C. This is followed by 2.7 meters of blowless run while moving to the subsequent fabric and to a new impingement unit, whereat the web temperature falls to 65° C., that is, approximately 9° C. is lost from the temperature increase of 29° C. Over six meters the decrease is 6.5° C. or more. Over a blowless interval of 8 meters the web temperature decreased further to 55.5° C., i.e. by 19.5° C. Lighter paper cools down faster and heavier paper correspondingly cools down slower. This blowless length varies due to, for example, the web transfer geometry, moving from a fabric to another, the space required by the lead rolls, or the required transfer fabric.
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An arrangement and method for improving runnability, and dryer section length, by using a vertical impingement dryer before a first dryer cylinder of a group of dryer cylinders. After a pressing section, the web is dried with a pre-impingement dryer, closely followed by a vertical impingement dryer, which is closely following by the first dryer cylinder. The pre-impingement dryer and vertical impingement dryer of the first dryer cylinder to have a drying temperature of approximately 80° C. with no undesirable sticking to the dryer cylinder. The pre-impingement dryer can be arranged to dry a first side of the web, and a vertical impingement dryer after the first dryer cylinder is arranged to dry a second side of the web. The impingement drying takes place directly against the web without an intervening fabric.
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PRIORITY AND RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 61/831,719, filed Jun. 6, 2013, entitled “Silicon Film on Sapphire Glass,” which is incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention is related to producing large grained to single crystal semiconductor films, such as silicon films, for producing articles such as photovoltaic and other electronic devices.
BACKGROUND OF THE INVENTION
[0003] It has been a long standing goal in the materials science community to produce large grained to single crystal semiconductor films on inexpensive substrates for cost effective electronic devices, such as photovoltaic cells and field effect transistors. One approach to solving this problem has been to deposit buffer layers such as Magnesium Oxide (MgO) and Aluminum Oxide (Al203) on glass or metal tapes thus creating a crystalline template, followed by deposition of a thin semiconductor film, such as silicon which has been induced to grow epitaxially or with strong texture. Yet, as of the date of this disclosure, large grained to single crystalline semiconductor films have not successfully been grown with quality equal to or comparable to single crystal substrates such as those used in the microelectronics industry.
[0004] Recent progress in materials research and development has however now opened up a new way to achieving the goal of depositing large grained to single crystalline semiconductor films on inexpensive glass, such as soda-lime glass. This is due to the invention of two important steps:
1.Heteroepitaxial deposition of silicon film on Al 2 O 3 (sapphire) below the softening temperature of soda-lime glass (−600° C.) as disclosed in US 2009/0297774 (Chaudhari et al). 2.Single crystalline (Al 2 O 3 ) sapphire glass is disclosed in US 2013/0236699 (Prest et al).
[0007] Here we disclose a way of depositing large grained to single crystalline semiconductor films. The act of deposition consists of combining the above two inventions, thus achieving a cost effective method of depositing large grained to single crystalline semiconductor films on inexpensive glass for photovoltaic and other electronic applications.
OBJECT OF THE INVENTION
[0008] It is an object of the present invention to provide large grained to single crystal semiconductor films, in particular silicon films, for photovoltaic technology and other semiconductor devices.
[0009] It is yet another object of this invention to provide single crystal or large grained semiconductor films, in particular semiconductor films, at low temperatures. For example, if silicon films are used, the growth temperature is between 450° C. and 650° C.
[0010] It is yet another object of this invention to provide single crystal or large grained semiconductor films, particularly silicon films, on inexpensive (soda-lime) glass consisting of a sapphire (Al 2 O 3 ) crystal layer.
[0011] It is yet another object of this invention to provide single crystal or large grained semiconductor films, particularly silicon films, on soda-lime glass, on which there is a large grained sapphire (Al 2 O 3 ) crystal layer.
[0012] It is yet another object of this invention to provide single crystal or large grained semiconductor films, particularly silicon films, on sapphire glass.
SUMMARY OF THE INVENTION
[0013] In accordance with one aspect of the present invention, the foregoing and other objects can be achieved by patent publication US2009/0297774, in which a method for depositing semiconductor films such as silicon on sapphire (Al 2 O 3 ) and soda-lime glass at low temperature, below the softening point of soda-lime glass, is disclosed.
[0014] In accordance with another aspect of the present invention, the foregoing and other objects can be achieved by depositing a semiconductor film, such as silicon, on sapphire glass, or on a glass substrate provided with an Al 2 O 3 layer on the surface of the glass disclosed in patent publication US 2013/0236699.
[0015] The combination of these two steps enables a new method avoiding the necessity of an Al 2 O 3 (sapphire) buffer template layer, or any other layers, which is more cost effective and could allow for the first time the deposition of a single crystalline to large grained semiconductor film, such as silicon, on glass, for highly efficient and cost effective electronic devices.
DETAILED DESCRIPTION OF THE INVENTION
[0016] A method for growing large grain to single crystalline semiconductor films on inexpensive substrates, such as soda-lime glass, is provided. A sapphire glass substrate consisting of a large grain or single crystalline layer or coating of sapphire (crystalline Al 2 O 3 ) on the surface of the glass is held at a constant temperature in a vacuum system. The temperature will vary according to the glass used. For example, soda-lime glass would require a temperature of at most 600° C. Next, a thin metal layer is deposited on the sapphire glass by any of the methods known in the art, for example electron beam evaporation. Many different metals can be used, but must all be able to form a eutectic alloy with the semiconductor to be deposited. An example of such an alloy would be aluminum and silicon (Al—Si). After the metal film is deposited, a semiconductor film is then deposited on the metal film also by e-beam. The resulting eutectic alloy allows for the precipitation of the semiconductor film onto the sapphire glass. The metal component of the alloy rises to the surface of the film now deposited on the sapphire glass and upon cooling can be etched away. A thicker semiconductor film can now be deposited on the semiconductor on sapphire glass substrate and used for various electronic applications, such as solar cells.
Example of the Invention
[0017] A good high vacuum system with two electron beam guns is used to deposit aluminum and silicon independently. A sapphire glass substrate consisting of a layer or coating of crystalline Al 2 O 3 is held at a temperature of 575° C. This is a nominal temperature. It is understood to one skilled in the art that lower or higher temperatures can also be used depending on the softening temperature of the glass substrate. A thin Al film of 6 mm thick is deposited on the sapphire glass followed by a 100 nm thick silicon deposition and a two phase region comprising of solid silicon and a liquid Si—Al mixture is reached.
[0018] The deposition is stopped and the sample is slowly cooled to room temperature. Aluminum diffuses through the silicon film, driven by its lower surface energy relative to silicon. The silicon film is heteroepitaxially aligned by the Al 2 O 3 surface on the glass. The aluminum film on the surface can be etched chemically by well-known processes to leave behind a silicon film. The surface of this film can now be used for further growth of epitaxial films either for photovoltaic devices or other electronic devices such as field effect transistors.
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A method is disclosed for growing large grain to single crystalline semiconductor films on inexpensive glass substrates. The method comprises deposition of semiconductor films from a eutectic melt on sapphire glass
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BACKGROUND OF THE INVENTION
The present invention relates to a vehicle door.
Motor vehicle doors, for motor cars as well as for trucks, as a rule comprise trim facing towards the vehicle interior. These trims accommodate an actuation lever for the door opening, which is rotatably mounted about a pivot arbor in a bearing block belonging to the door. Here, usually a peripheral gap arises in the region between the actuation lever and the trim which encompasses this.
In particular with high-quality motor vehicles, it is important that no unsatisfactory gap appearance (gap which is too large, changing gap width) between the actuation lever and connecting parts of the trim occurs.
At the same time it is a problem that due to the fact that several components are involved, usually high manufacturing tolerances are set on all the individual components, so that when combined, an unsatisfactory gap appearance may result a later stage.
To solve this problem, it is possible to form a bearing block in a shell shape (thus quasi as a separate door inner trim), which engages behind the door inner trim towards the vehicle interior. Here only a gap between the actuation lever and the directly visible surrounding bearing block is created, and on account of the shortness of the tolerance chain, the gap appearance here is simple to realise. However with this, it is a problem that a relatively “clumsy” appearance arises which results from the protrusion of the bearing shell into the vehicle interior, and this hinders a harmonic overall appearance. Furthermore it is a problem that the bearing shells need to be manufactured of a relatively strong plastic which is cost-intensive and because of great demands on the surfaces, needs to be additionally painted, and in turn higher costs arise due to this.
It is of course also possible to shape the complete door inner trim of such a high-strength plastic (such as e.g. polyamide). However even greater manufacturing costs arise on account of this.
Another solution lies in the fact that due to “rolling” gaps between the actuation lever and the connecting trim, one succeeds in these not being conspicuous, even with uneven gaps. However the problem here is that the geometries of the door trim are very greatly restricted.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention therefore lies in creating a door for motor vehicles which may be manufactured in an inexpensive manner and which fulfils the high demands with regard to the gap dimensioning.
This object can be achieved by a door for a vehicle with an interior and an exterior, which door comprises a trim facing toward the vehicle interior. The trim is connectable to a bearing block in which an actuation lever is pivotally mounted about a rotation arbor. A gap is, at least in regions, present between the actuation lever and the trim, and the arbor is additionally connected to the trim via fixation bearings.
Because of the fact that the arbor is additionally connected to the trim via fixation bearings, it is easily possible to achieve a uniform gap appearance. This is due to the fact that the tolerance chain is quasi “shortened”, i.e. that an additional direct coupling between the trim and the arbor of the actuation lever is created (without the “detour” via the bearing block). Therefore, it is no longer necessary to demand that all components in a long tolerance chain have high manufacturing and gap tolerances in order as a whole to achieve a harmonic gap appearance. The reduction of the occurring tolerances is thus achieved without a limitation of the tolerance in manufacture.
Also, it is not necessary to manufacture the trim itself of a particularly stable expensive material. The fixation bearings assume merely the positioning or centering of the actuation lever to the connecting trim. The actual accommodation of force may take place in a conventional manner, e.g. via screw domes on that side of the trim which is distant to the motor interior. In particular with the solution according to the invention, is possible to fit the actuation lever into a trim in a flush manner. No bearing blocks etc. which project into the motor interior are required.
Advantageous formations of the present invention are specified in the dependent claims.
One advantageous further formation envisages the trim to be of polypropylene. This is a plastic capable of being manufactured inexpensively and which has a satisfactory surface quality without paint. This is particularly suitable for motor vehicles such as trucks, small buses, etc.
One further advantageous formation envisages the trim to be of several parts. This trim may e.g. consist of a first part and of a second part both of which comprise a surface directed towards the motor vehicle interior. In this manner it is easily possible to manufacture doors of two colours. The first and second part may e.g. consist in each case of differently coloured plastic and thus it is possible without expensive painting to influence the optical appearance of the door with regard to colour. Here it is particularly advantageous for the first part to be designed as an upper part which forms the inner breast or beltline of the motor vehicle door, and the lower part to be formed by a base carrier which, proceeding from the upper part, continues downwards to the door lower edge. This base carrier may contain openings for loudspeakers or rests, etc.
A particularly advantageous further formation envisages screw domes or likewise (rivet receivers etc.) being arranged on the second part of the trim, for fastening of the bearing block on the second part with a non-positive fit. Here it is essential that by way of this e.g. screw connection, only a tensioning takes place in order to hold the bearing block, and the actual geometric centering or exact definition of the position is accomplished by the fixation bearing indicated above. For this reason it is significant for these screw domes or likewise to have play in their condition of not being tightened so that depending on the setting of the additional fixation bearing, the screwing accommodating the force may be carried out in the different positions (a mechanical redundancy is avoided by way of this). It is particularly advantageous then on the first part of the trim, thus here e.g. of the window beltline or breast, to attach the fixation bearings for the unambiguous positioning of the arbor with respect to the trim.
This is also advantageous on assembly, thus the bearing block e.g. is introduced into the first part and positioned by way of this. For this the fixation bearings e.g. may have run-in chamfers. The screwing which is effected after this is however not significant with regard to the tolerance but merely serves for tensioning. It is yet to be emphasised that the fixation bearing ensures the actual centering or fixation or setting of the gap magnitude.
A further design envisages the bearing block being sunk with respect to the trim towards the vehicle exterior. By way of the fact that the bearing block or the trough for the actuation lever which contains it, into which e.g. an operators hand engages, does not protrude partly to the vehicle interior, this part does not also need to be painted or finished in any other manner in order to achieve demands set on the surface qualities, since the covered trough is practically not visible.
One advantageous design envisages the bearing block or the actuation lever being of polyamide. This plastic has good strength properties. E.g. the actuation lever may also be painted where there are very high demands on the surface.
A further advantageous design envisages the fixation bearings being designed as receivers open on one side. These may e.g. be “U” shaped, possibly with run-in chamfers and a locking bulge. By way of this it becomes possible to position the bearing block before it is then screwed to the trim in this position. A fastening of the arbor position in the axial direction is additionally possible.
Further advantageous designs of the present invention are specified in the remaining dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is hereinafter explained by way of several figures. There are shown in:
FIG. 1 a view of a cut-out of a motor vehicle door according to the invention, from the motor vehicle interior,
FIG. 2 a a cross section through the motor vehicle door shown in FIG. 1 ,
FIG. 2 b a detailed view of a fixation bearing according to the invention,
FIG. 3 an alternative embodiment with less favourable tolerance conditions.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a motor vehicle door 1 according to the invention which comprises a trim 3 facing towards the passenger space of a motor vehicle. The trim in FIG. 1 is seen from the vehicle interior, and the trim 3 is of two parts. The trim consist of an upper part 3 a as well as of a lower part 3 b which are firmly bonded or welded to one another. The upper part 3 a forms a window breast or beltline towards the window 12 of the motor vehicle. The lower part forms a base carrier of the trim in which rests or a loudspeaker opening not shown in FIG. 1 are incorporated. The trim as a whole is fastened on a door module or a frame of a motor vehicle door. The parts 3 a and 3 b are in each case of unpainted polypropylene. Both parts are coloured with a different colour in that in the trim, a different colouring for the breast or beltline part and the base part results when viewed.
An actuation lever 5 mounted in an articulated manner is arranged surrounded by the upper part 3 a . This actuation lever in regions forms a gap with the surrounding upper part 3 a ; this joint in its upper region is indicated at 7 b and at its lower region at 7 a.
It is the main aim of the present invention to design this gap over its whole length as uniformly as possible, wherein at the same time a uniform view is to result with as low as possible costs.
The actuation lever 5 is arranged essentially flush to the trim (see FIGS. 2 a and 3 ), and below the actuation lever a trough belonging to the bearing block 4 is arranged into which an operator's hand may engage in order to grip behind the actuation lever 5 .
The bearing block as well as the actuation lever 5 are of unpainted or painted polyamide.
FIG. 2 a shows a cross section according to A-A (see FIG. 1 ) through the motor vehicle door according to the invention. Here a part of the motor vehicle door 1 is to be seen which comprises a trim 3 (consisting of the parts 3 a and 3 b ) towards the passenger space 2 of the motor vehicle. The trim 3 may be connected to the bearing block 4 , e.g. via screws. In the bearing block 4 , the actuation lever 5 is pivotally mounted about a rotation arbor 6 , wherein between the actuation lever 5 and the trim 3 , a gap 7 a and 7 b is given at least in regions. The arbor 6 is additionally connected to the trim via fixation bearings 8 a and 8 b.
FIG. 2 a is now explained in more detail after this general description. One may easily recognise that the trim 3 consist of the upper part 3 a and the lower part 3 b . The upper part 3 a and the lower part 3 b are e.g. welded to one another in the region 13 . The lower part 3 b comprises screw domes 9 a and 9 b into which screws 14 are screwed. These screws 14 engage behind bores in the bearing block 4 and thus in the firmly screwed condition fix the bearing block 4 on the screw dome 9 a and 9 b . The through-bores in the bearing block 4 have a larger diameter than the shanks of the screws 14 so that when the screws are not tightened, no exact geometric fixing of the bearing block 4 on the trim is given, but rather a coupling “having play”.
The bearing block 4 comprises a trough 15 which is set back with respect to the motor vehicle interior 2 . As a whole the bearing block 4 is sunk with respect to the trim towards the vehicle exterior, so that this is practically not visible from the interior. An arbor consisting of plastic or metal is mounted in the bearing block 4 via two through-openings, and is pivotally mounted with the actuation lever.
This arbor 6 is furthermore mounted in fixation bearings 8 a and 8 b . These fixation bearings 8 a and 8 b belong to the upper part 3 a . Here for example it is the case of injection moulded webs of the upper part 3 a.
The fixation bearings 8 a and 8 b are designed e.g. as “U”-shaped receivers, thus open at one side (see FIG. 2 b ). These, as shown in FIG. 2 b , may have run-in chamfers in the region of the limbs of the “U” and serve for fixing the arbor 6 .
With the assembly of the subject shown in FIG. 2 a , firstly the upper part 3 a and the lower part 3 b are welded into a finished trim. Then the actuation lever 5 via the arbor 6 is assembled in the bearing block 4 . Then from the rear side of the trim (thus the direction of the reference numeral 10 in FIG. 2 a ) the bearing block 4 is fixed in that the arbor 6 is fixed in the fixation bearings 8 a and 8 b open towards the reference numerals. By way of this fixation, the geometric position of the arbor is exactly defined i.e. the axis is centred in an exact manner. In this position then the screws 14 are screwed through the through-openings of the bearing block 4 into the screw dome 9 a and 9 b and tightened so that a non-positive fitting fixation of the bearing block in the position predefined by the fixation bearing 8 a and 8 b is effected.
By way of the short “tolerance chain” between the actuation lever 5 as well as the trim 3 (or the upper part 3 a ), it is ensured that the gap 7 a and 7 b runs in a uniform manner also without great manufacturing and gap tolerances. Thus a harmonic appearance of the actuation lever arises in the trim, and this is the case with the gaps as well as for the flush incorporation of the actuation lever with respect to the trim. In FIG. 2 a one may easily see that the actuation lever in the cross-sectional direction perpendicular to the vehicle longitudinal axis terminates essentially flush with the trim.
Finally a section according to FIG. 3 is shown for purposes of comparison. Here the parts are indicated with reference numerals corresponding to those of FIG. 2 a . The bearing block 4 ′ shown in FIG. 3 has an actuation lever 5 mounted via an arbor 6 ′. The screw domes 9 a′ and 9 b′ accommodate screws 14 which are guided through through-openings of the bearing block 4 ′ and engage behind the bearing block 4 ′. The spring domes engage essentially with a positive fit into the through openings of the bearing block 4 ′ so that its geometrical position has already been completely defined by way of this. A securement from detachment is finally effected by way of the screws 14 .
The design has the disadvantage that the gaps 7 a′ and 7 b′ only have a satisfactory quality with regard to the dimensions when a multitude of components (screw dome 9 a′ , 9 b′ , bearing block 4 ′, arbor 6 ′, actuation lever 5 ) are machined in a very accurate manner and are also joined according to the directed manner. If errors occur in this relatively “long” tolerance chain this unavoidably leads to deviations in the dimensions with the gaps 7 a′ and 7 b′ which may manifest itself in an unsatisfactory optical appearance or may even lead to jamming of the actuation lever 5 on the trim 3 a′ and 3 b′.
The essential advantage of the design according to FIG. 2 a is the fact that the tolerance chain, by way of the direct coupling via the fixation bearings 8 a or 8 b , is shortened towards the arbor 6 so that an excellent joint appearance arises without an expensive restriction of the tolerances.
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The invention relates to a vehicle door having a lining that faces the passenger compartment of a motor vehicle. The lining can be joined to a bracket inside of which an actuating lever is mounted in a manner that enables it to swivel around a pin. A gap is provided at least in areas between the actuating lever and the lining. In addition, the pin is joined to the lining via fixing bearings.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention refers to a hydraulic packing device for wellbores, known in the art as “packer”, which is a retrievable device and is used in downhole operations, that is also part of the tools used in wellbore operations, such as oil, water or gas wells, or wells of similar fluids. More specifically, the main object of the invention is a double-latch packer with hydraulic fastening and packing pressure function, double retreat integrated assembly, with elements of rubber packing, which has the advantage of being able to work selectively on facilities with one packer or multiple packers, with the advantage of fastening or releasing the packer selectively in oil, water or gas wells, or wells of similar fluids.
[0003] 2. Description of the Prior Art
[0004] Within the field of the prior art, several packers are known, which are currently used as retrievable packing tools in oil, water or gas wells, or wells of a similar fluid, where it is necessary to isolate areas in order to carry out production or injection works.
[0005] Some of those packers known by the art, so far have the great disadvantage that, when releasing the installation formed by more than one of these packers, they need expansion joints in order not to add individual release efforts; generally they are packers of stress release.
[0006] Other devices of this type use rotation releases, which, in the case of installations of more than one packer, make it impossible to rotate de string due to the simultaneous addition of all the release rotation assemblies of each of them, generating an excessive torque when doing it.
[0007] As an example, we can cite double latch hydraulic packers that present a number of inconveniences or limitations, such as the following:
[0008] In the first place, we could mention the fastening hydraulic packer, whose release assembly is carried out by the string rotation and, as a consequence, by the mandrel of the packer. This kind of model presents the limitation of having to generate several spins to unpack the rubbers and finally disengage the clamps. In wells with degrees of inclination or where, as part of the installation, there are intermediate injection devices, it is very difficult to generate the necessary spins in order to obtain the release of the tool, due to the generation of high torques in the maneuver string, which makes it impossible. Moreover, it goes without saying that it would be even more difficult if the installation had more than one packer with this release assembly, because there would be an addition of the rotation efforts of each of the packers.
[0009] Secondly, we could mention the hydraulic fastening and stress release packer. This kind of model has the feature that, in order to release the tool once it has been fastened, traction must be applied over the mandrel to cut the safety assembly and to release the packer completely. If there are installations with several packers, the forces on each of them to release are joined, since packers help each other through the mandrels. The production strings have a limitation in the corresponding traction that is solved with this type of installations. In other words, it is necessary to have some kind of intermediate supplementary device to compensate the forces of each packer and not to transmit it downward to the other packer. Another limitation to bear in mind is that in some of these packer models, the mechanical works of the tubing between packers derived from the pressure changes might generate stress or cuts in the safety mechanisms, which causes an early release of the tools.
SUMMARY OF THE INVENTION
[0010] Therefore the object of the present invention is to provide a double grip packer with hydraulic fastening and packing pressure capable of solving the inconveniences mentioned earlier, being a packer that offers an original result, which includes a bigger fastening confidence, simplicity in the release operation, which is highly recommendable in the use of the selective installations of multiple packer, with the advantage of being able to fasten or release the packers selectively without letting the production or maneuver string suffer traction efforts or excessive rotation.
[0011] In comparison with the packers mentioned, the packer of the present invention presents several outstanding features that allow fulfilling the needs and coping with the deficiencies of the existing packers for this type of applications that the market offers. The present packer includes mainly the split mandrel, base of this invention, that has a mandrel or upper part, and a mandrel or lower part, connected through a threaded connection, an upper anchoring assembly that, once the packer is released, allows the upper mandrel of the packer to help its intermediate peripheral portion, a corrugated assembly that allows the lower mandrel and its intermediate peripheral portion to help each other, and from there downward to the rest of the installation, an anchoring assembly that, when releasing the packer, prevents it from being packed again. All this assembly, once the packer is released, manages to make this act as if it all was a rigid assembly and allows it to transmit stress, weight or torque, in an independent fashion downward, without consuming efforts to release another packer or other part of the installation, or to simply retrieve it and take it out of the well. It also has a hydraulic fastening pressure assembly, which activates a hydraulic chamber that starts its course cutting shear pins and comprising the package of elements or packing rubbers, which can be added or taken out depending on the state of the well or the work to be carried out; this compression of packing elements is sustained by safety assembly that prevents its unpacking once the hydraulic pressure has been released; at the same time, the packing package exerts a force on the upper cone that fastens the gripping means of both directions created by double latch clamps that can be set up as comprehensive or individual clamps, depending of the configuration of the wells and the forces to support; at the same time, these clamps can have treated latch teeth or hard metal inserts.
[0012] As described, one of the most important virtues of this packer model is that the release is achieved with less than one spin of the maneuver or production string, without transmitting torque at the lower part of the packer, when releasing the packer, due to the fact that the split mandrel is connected with a quick thread. Once this thread is disengaged, the upper mandrel is raised and the packing assembly contained is released; the string keeps being raised while the clamps are released. Then the upper mandrel is connected to the periphery of the packer, through the tower, and this periphery with the lower mandrel of the packer, through the spire. In this way, the packer is absolutely free in terms of the tightness of the packing elements, in the shape of rubbers, over the well casing, and in terms of the casing latch, allowing it to release another packer under itself or under part of the installation, as in this state it will transmit, stress, torque or weight as a solid whole.
[0013] Another great advantage is that, due to the geometry of the mechanism, it allows larger interior diameters in the junctions of the mandrel, which are very useful in the use of this type of packer for the selective installations, as it is very common to pass tools of smaller diameter through the mandrel of the packer.
[0014] Comparing the packer of the invention with the other two retrievable packer variants already mentioned the advantages that the invention offers are:
[0015] In relation with the making mentioned earlier, the packer of the present invention presents the advantage that, at the moment of the release, a rotation of the upper mandrel can be carried out of less than one independent spin of the lower part, without transmitting torque at that moment towards the lower part of the tool and, as a result, towards the rest of the installation. This is so because the present packer has a split mandrel that, at the moment of the release, allows it to apply only the torque necessary to release this quick thread, and with this, to easily start with the release of the packer, without transmitting that torque downward. After this thread is released, the tubing is raised and the packing elements loose compression. As a result of that upward movement, the clamps are released, and at the same time the upper mandrel is inserted in the tower, allowing the periphery of the packer to help the upper mandrel, and this one to help the lower one; therefore, with just a small torque of less than one spin and an upward movement, not only the packer in question is released, but it is also ready to act as a rigid assembly to exert rotation movements of weight and traction in order to keep moving the string, with the aim of releasing the other lower packer and other tools of the installation.
[0016] In relation with the making mentioned secondly, the packer of the present invention presents the essential advantage that it does not require stress to be released, it only needs a small rotation of less than one spin, and therefore, in its anchoring assembly and tightness it is not tied to bolt cutting assemblies that may be cut easily due to the tubing pressure in the mechanical work, but mainly that the released assemblies by stress need to stress the spring and if the installation has more than one packer of these features, the efforts to cut the release bolts are to one another, making an assembly like this very difficult to release, as the sum of all the cutting forces of each packer exceeds the traction mechanical capacity of the tubing. Note that there are wells with considerable deflections, where the stress forces—due to the pulling of the tubing in the casing—limit the capacity to maneuver with stress these installations. Completing this explanation, we can mention that the packer of the present invention is independent of the mechanical works that the tubing might have due to the pressure changes, as its double latch fastening assembly is independent of any other type of movement. Once the casing is fastened, the weight or stress can be applied to it, without any limitation needed for its operation and without affecting its functioning. We know that when there are increases in the pressure within the tubing located between two packers that help the casing of the well, the tubing experiences a swelling that produces a stress increase on its ends, that is, it tends to shorten, therefore in the packer technology with stress release it can generate a release that is carried out before the required one.
[0017] In many aspects, the present packer is a tool that presents many advantages: It comprises mainly a mandrel with an upper part and a lower part axially connected to each other through a quick sealed thread fastened with a shear pin calibrated for torque, therefore, it supports internal and external pressure, traction and weight. The direction of the thread can be configured from right to left according to the features of the installation to be lowered or according to the well.
[0018] It has a safety pin assembly configurable to prevent the accidental fastening of the tool, which allows to select both the amount of pins and materials in order to establish the exact pressure needed to start with the fastening.
[0019] The packer of the invention has an upper insert assembly that, once the tool has been released, allows the portion of the upper mandrel of the packer to help the intermediate peripheral portion of the tool. This assembly is formed by an insert known as tower, being one part located in the lower portion of the segment carrying sleeve, and the other, in the part located in lower part of the upper mandrel. It is a notched assembly that, when the teeth of the upper and lower parts touch each other and couple, allows the torque to be transmitted from the upper part of the packer towards the intermediate part, that is, to the parts that can help the others. It also has a corrugated assembly located in the lower mandrel and the joint sleeve, connecting in terms of torque the intermediate peripheral portion with the lower mandrel, allowing also in this way to transmit torque, but allowing the movement of the joint sleeve at the time of the fastening, in order to compress the packing elements. This is why the torque can be transmitted when it is free, from the upper mandrel through the periphery towards the lower mandrel, and from there to the rest of the installation or to whatever there is under the packer. The present packer also has a locking ring assembly that, at the time of releasing the packer, prevents this one from returning to its previous position, that is, to being packed and wedged. This is achieved because at the time of turning and splitting the upper mandrel, the extension assembly is stuck in terms of length, due to the safety bolt, and rigid, in terms of the torque, due to the tower and spire insert assembly. All this assembly, once the packer is released, manages to make this act as if it all were a rigid assembly and allows it to transmit stress, weight or torque, in an independent fashion downward, without consuming efforts to release another packer or other part of the installation, or to simply retrieve it and take it out of the well.
[0020] The fastening assembly of the packer of the invention operates with hydraulic pressure. In order to carry out the fastening of the packer, it is necessary to smother the lower mandrel temporarily so as to generate enough hydraulic pressure within the mandrel to start with the injection. The hydraulic pressure activates a hydraulic chamber that begins its route cutting safety pins, moving downward and compressing the package of elements or packing rubbers. This package of packing elements, in turn, compresses an upper cone cutting other security pins and anchoring the clamps of the well casing. The amount and hardness of the packing elements can vary depending on the state of the well or the work to be performed; this compression of packing elements is supported by safety bolt assembly with saw tooth located in the segment carrying sleeve, which prevents its unpacking and assembly restitution, once the hydraulic pressure has been released.
[0021] The present invention comprises gripping means in both directions generated by double latch clamps that can be configured as comprehensive or individual clamps, depending of the features of the wells and the forces to support; these clamps in turn can be hardened treated gripping tines or tines with hard metal inserts.
[0022] The present packer comprises security stages controlled by calibrated shear pins allowing to configure selectively the necessary pressure to exert the forces in the different parts of the tools; and not only in one tool, because if the packer is a part of the installation of the different packers of the invention, the security assembly of these can be configured in a different way selectively to be able to control, together with the different pressures, which of them needs to be fastened to the casing first and in what stages.
[0023] One of the most outstanding virtues of this packer is that the release is achieved with less than one spin in the maneuver or production string. This thread is secured through a shear pin calibrated by torque, which to fracture it requires a certain calculated torque to make the turn begin. The aim of this shear pin is to prevent the packer from being free due to any accidental turn of the maneuver or production string. The direction of the turn can be configured to the right or to the left, depending on the operative needs. For this release, it is necessary to transmit only torque to the upper mandrel and also to disengage the quick thread, because as it has its split mandrel connected only with the quick thread, this is easily achieved. Once this turn is achieved and it disengages the thread that connects the mandrel in two parts, the parts quickly disengage, it is raised and with this the packing assembly contained is released. If there was a pressure difference between the interior and the exterior of the packer, once the thread is released, raising the upper portion of the mandrel makes the balance orifice in line and balances the pressures. After this, the packing assembly is completely unpacked because the tool is balanced.
[0024] The packer has a release safety assembly that prevents the packing and the tool latch from being free once it is completely released; this is achieved through a locking ring that prevents the packer mechanism from being packed again and having the clamps of the well casing fastened.
[0025] Another essential advantage of this packer is that, once the tool has been released and secured, it acts as a rigid whole that can transmit torque, weight or stress to the rest of the string or installation, or can take it out of the well. This is achieved because when the string is raised and in turn releases the clamps, the upper mandrel is connected to the periphery of the packer through the tower, and this one is connected to the lower part through the spire. In this way, the packer is absolutely free in terms of the tightness in the casing and in terms of the latch on the well casing, allowing it to perform the maneuvers required, such as releasing the packer below it or another part of the installation.
[0026] Due to the geometry of the mechanism, the present packer allows larger interior diameters in the joints of the mandrel, which are very useful in the use of this type of packer for the selective installations, as it is very common to pass tools of fewer diameters through the mandrel of the packer.
[0027] Therefore, the object of the present invention is to provide a retrievable packer and one that can be used in downhole operations that is part of the tools used in wellbores, specially used for the selective installations, such as oil, water or gas wells, or wells of similar fluids. More specifically, the main object of the invention is to provide a double latch packer with pressure hydraulic fastening and packing, double integrated safety bolt assembly with elements of rubber packing, which presents the advantage of being useful on installations of multiple packers with the purpose of solving the problems that arise from incidental releases and the excessive forces at the time releasing the installations of multiple packers, with the benefit of fastening or releasing the packer selectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] For more clarity and comprehension of the object of the present invention, a figure has been drawn, as an example, in which the invention has been represented with the preferred (possible) embodiment, where:
[0029] FIGS. 1 a and 1 b show a profile view in vertical semi-cut of the preferred embodiment of the packer of the present invention, as an example.
DETAILED DESCRIPTION OF THE INVENTION
[0030] Describing the exemplifying device of the present invention and making reference to the Figure, it can be observed that the retrievable hydraulic packer with double latch comprises a tool to be applied when it is necessary to isolate or seal temporarily or permanently the well area, with the possibility to carry out different operations, specially used on selective installations, such as oil, water or gas wells, or wells of different fluids.
[0031] The packer of the present invention comprises, in the upper end, an upper header 1 , that may have a male or female thread, where there is a mandrel threaded, which according to the invention, is a split mandrel formed by an upper mandrel 3 and a lower mandrel 17 . Mandrel 3 is isolated by seal 2 and over upper mandrel 2 there is a compression safety assembly formed by pin 4 that houses in its periphery a plurality of safety shear pins 4 and the screw 5 that is used to retain and press the shear pins 6 against the notches of the upper mandrel 3 . Threaded to pin 4 , there is segment carrying sleeve 7 that houses segment 8 , segment carrying cone 9 and friction ring 10 . In the lower part of segment carrying sleeve 7 there is a plurality of teeth 7 A known in the art as battlement-shaped teeth.
[0032] Threaded to segment carrying sleeve 7 there is hydraulic sleeve 11 , whose upper part houses pressure balance orifice 35 .
[0033] Upper mandrel 3 has in its lower part a plurality of battlement-shaped teeth 3 A and can house O-ring seals 13 and shear pins 15 . These shear pins 15 fasten upper mandrel 3 with lower mandrel 17 to prevent that an incidental torque releases the tool that is, they are calibrated with a calculated torque to break them and make the turn to release the tool.
[0034] Lower mandrel 17 is threaded through a quick thread to upper mandrel 3 and, in turn, isolated hydraulically through O-ring seal 12 and 14 . On its upper part, below O-ring seals 14 , there is balance orifice 36 towards hydraulic sleeve 11 , where the pressure needed to begin the movement of hydraulic sleeve 11 downward originates.
[0035] Threaded to hydraulic sleeve 11 , there is joint sleeve 18 . On the upper part of joint sleeve 18 , seal 16 is housed, which has the function of tightening the thread with hydraulic sleeve 11 . On the lower internal part of joint sleeve 18 , there is spire 18 A. Spire 18 A works over spire 17 on lower mandrel 17 . This spire assembly allows joint sleeve 18 to freely move vertically along lower mandrel 17 , but it transmits torque from one component to another, that is to say, from joint sleeve 18 to lower mandrel 17 , thanks to the spire. Over the lower part of the joint sleeve, there are O-ring 19 seals housed that move along lower mandrel 17 at the time of the fastening, therefore forming complete hydraulic chamber 37 internally formed by lower mandrel 17 , in the upper position by upper mandrel 3 and in its periphery by hydraulic sleeve 11 and joint sleeve 18 .
[0036] Threaded outside joint sleeve 18 , there is upper gauge ring 21 , which can be changed and configured with different diameters according to the internal diameters of the well casing. Threaded on joint sleeve 18 , there is rubber carrying case 22 , which comprises the packing assembly.
[0037] The packing assembly described next works over carrying rubber sleeve. The packing assembly can be configured varying the dimensions and the geometry according to the operational needs and also choosing to change the number of rubbers 23 and spacer rings 24 , being able to achieve more tightness safety. In the case of the illustrated embodiment, the packer is configured with an assembly of three rubbers 23 and to spacer rings 24 . The configurations of rubbers 23 in terms of hardness, diameters and geometry change depending on the internal diameters of the well tubing.
[0038] On the lower part of rubber carrying sleeve 22 there is a buffer on which lower gauge ring 26 is stopped. Threaded to the lower gauge ring 26 , there is upper cone 27 .
[0039] Housed on the lower notch of lower mandrel 17 , there is locking ring 25 restrained by pressure between lower mandrel 17 and rubber carrying sleeve 22 . This ring has a safety function on which after the packer release and when this is stretched, the lower end of rubber carrying sleeve 22 moves upward to locking ring 25 , and this one expands itself to be under pressure, preventing rubber carrying sleeve 22 from descending again. In this way, the packing and anchoring assemblies are secured, which cannot return to the compression state. This allows to handle the tool in the well freely and without running the risk of being stuck or anchored.
[0040] The anchoring assembly of the present packer comprises unidirectional latch that can be configured as comprehensive or individual clamps, depending on the configurations of the wells and the forces to support; these clamps in turn can have hardened treated latch tines or with hard metal inserts.
[0041] In the case of the illustrated embodiment, it comprises a package of clamps 29 which are contained between upper cone 27 , lower cone 34 and clamp carrying sleeve 32 . In turn, shear pins 28 are housed on the lower part of the upper cone with the aim of preventing the involuntary movement of the parts of the anchoring assembly and therefore preventing any latch to the well casing that was not intended until the moment of fastening.
[0042] Finally, on the lower part of lower mandrel 17 , lower cone 34 is threaded, sealed with an O-ring 33 seal housed on lower cone 34 . The lower end of lower cone 34 is threaded, the thread can be cut as male or female, according to the installation connection that is below the packer.
[0043] Operation of the packer:
[0044] Now there is a description of the operation of the packer, object of the present invention.
[0045] Let us bear in mind that the packer can be lowered individually if just one packer needs to be installed or if it is a part of a multiple installation of packers. For operation purposes of the fastening and release, we can consider the same operative maneuvers individually.
[0046] In order to describe it more clearly, we will divide the assemblies in four parts, the fastening assembly in the upper part of the packer, an hydraulic assembly in the intermediate upper part of the packer, a packing assembly in the intermediate lower part of the packer and finally an anchoring assembly in the lower part of the packer.
[0047] Fastening: Once the packer is threaded to the tubing, the deepening operation is carried out until the required area for its operation. With the mandrel of the packer temporarily blinded under it or blinded under the installation. In general, a ball seal is used that allows to fill the maneuver or production tubing from down to up, but when applying pressure, the ball covers the orifice allowing to apply hydraulic pressure previously and configured on surface through shear pins calibrated specifically for that housed on the seat, up to a point in which the ball is expelled together with the seat and the passing of the installation is on its full diameter. In this way, it allows to configure the maximum pressure of the packer fastening or the installation of multiple packers. Then hydraulic pressure is applied to the packer or to the installation through a tubing. As the inside of the packer is blinded, the pressure is imparted through the orifice located in the upper part of the lower mandrel and to the portion of the hydraulic assembly formed by the upper mandrel, the hydraulic sleeve, the joint sleeve and the lower mandrel. This hydraulic pressure generates a hydraulic force that becomes a mechanic force of the assembly. This mechanic force generates a movement to below all the assemblies of the packer (as the upper, mandrel is threaded to the string it does not move). The simultaneous movement begins by cutting the shear pins located on the pin case of the fastening assembly. Once these safety pins are cut, the descent of the fastening assembly begins, which is formed by segment, pin case, segment carrying sleeve, segment carrying cone and the friction ring, where the segment that has a saw tooth thread on its internal diameter slips along the upper mandrel, which also has a saw tooth thread on its external diameter. As the saw tooth cut is very small, its illustration is not very graphic, but it is something easy to understand for a technician. This allows that the movement can be performed from down to up, but not from up to down, thus preventing movement.
[0048] The hydraulic assembly helps the fastening, therefore, all the movement that can be achieved hydraulically will be the same as the one running along the fastening assembly. With the movement in process, the packing assembly, formed by rubber carrying sleeve, the rubbers and the spacer rings, the packing process begins. With the upper cone, part of the fastening assembly is subject to the force generated by the packing assembly and it will also start its descent together with all the other assemblies, but before the movement is performed in the anchoring assembly, the force of the upper cone will have to cut the shear pins housed between the upper cone and the clamp carrying sleeve, whose function is to prevent that the packer suffers an unwanted fastening in the input of the packer to the well and its descent within it, only until it is required.
[0049] Following the application of the hydraulic pressure of the packer will continue the descents of the assemblies and the rubber compression, increasing the tightness of the casing and the wedging of the clamp of the well casing, until the pressure value breaks the device located at the end of the installation described earlier and the pressure falls. At that moment, the packing assembly that is pressed with the packing force will try to restore itself, due to the memory condition of the packing elements of the rubber, but this is when the fastening assembly starts to work as such locking the assemblies: The anchoring assembly to the well casing, the packing assembly to the well casing and fastening to the lower mandrel. At this instance, we mentioned that the packer is fastened and packed to the well, sealing the tubing by annular portion, but allowing the passing of fluids through its interior and applying hydraulic pressures.
[0050] It is worth remembering that the installations of this kind may be formed by just one packer or multiple packers.
[0051] Release: In order to achieve the release of the packer, one should start by turning the string to the right (or left according to the configuration), exceeding the configured torque of the calibrated shear pin, which will cut, achieving a spin of less than one round, and at that moment, the upper part of the mandrel will disengage from the lower mandrel. The tubing and the mandrel are raised. After disengaging from the lower mandrel, the packing assembly which was compressed, sealed and isolated to the well casing will unpack. It may be that there was a very high differential pressure over the packing assembly in relation with the lower part of the packing assembly; in that case, the rubbers will remain compacted due to the pressure. In that case, the pressure will be balanced and the rubbers will unpack as we describe as follows. The upper mandrel will continue to be raised during the lifting of the upper mandrel, the safety assembly segment will continue to run along the upper mandrel until the tower of the upper mandrel reaches a limit and is inserted in the segment carrying sleeve of the tower, this is the moment when the upper mandrel helps the exterior of the packer and of the periphery of the packer to the lower mandrel through the spire. Continuing with the rising of the upper mandrel which now is helping the fastening assembly, the hydraulic assembly, the packing assembly and the anchoring assembly, the complete balance between the internal pressures of the mandrel and the one in the exterior of the packer is achieved through the upper orifices of the hydraulic sleeve and the packing assembly unpack completely and the clamps of the anchoring assembly are released due to the vertical movement of the upper cone, the clamps are drawn inside due to the compression of the spring and a fundamental thing is carried out that prevents the packer from being anchored again or being packed even with downward movements. When the assemblies are stretched upwards by the upper mandrel, the rubber carrying sleeve exceeds the locking ring; this one expands downward below the sleeve, preventing it from moving downward again, packing the rubbers and anchoring the clamps. At this moment, when the packer is completely free, being able to transmit torque from the upper mandrel to the below the lower mandrel, weight or stress, acting like a rigid unit.
[0052] This is why the packer of the present invention is ideal for releasing another packer that is located below the first one, and in turn this one for releasing another one and so on, without having torque added to each other, which allows performing one selective release operation at a time for each packer located on the installation.
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A hydraulic packing device for wellbores, known in the art as “packer”, which is a retrievable device and is used in downhole operations, that is also part of the tools used in wellbore operations, such as oil, water or gas wells, or wells of similar fluids is provided. More specifically, the main object of the invention is a double-latch packer with hydraulic fastening and packing pressure function, double retreat integrated assembly, with elements of rubber packing, which has the advantage of being able to work selectively on facilities with one packer or multiple packers, with the advantage of fastening or releasing the packer selectively in oil, water or gas wells, or wells of similar fluids.
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BACKGROUND OF THE INVENTION
[0001] Field of the Invention
[0002] The present disclosure relates to a method and apparatus for timing. The present disclosure relates more specifically to a method and apparatus for hook timing.
[0003] Description of Related Art
[0004] Machine quilting is quilting made using a sewing machine to stitch in rows or patterns using select techniques to stitch through layers of fabric and batting in the manner of old-style hand-quilting.
[0005] Free motion quilting is a process used to stitch the layers of a quilt together using a domestic sewing machine. The operator controls the stitch length as well as the direction of the stitching line by moving the quilt with their hands. The stitching can be made in any direction to make straight or curved lines to create patterns. The length of each stitch is determined by the distance the quilt has been moved since the previous stitch.
[0006] One method of creating a stitch in a sewing or quilting machine includes the use of a rotary hook or rotating hook. The rotary hook continuously rotates in place, hooking the upper thread each time its pointed tip passes the position of the reciprocating needle. Enough upper thread is then pulled from above to pass around the bobbin case, which sites loosely inside the hook frame such that loops of thread can pass completely over it. The excess thread, no longer needed, is then pulled back upward by the sewing machine's take-up arm.
BRIEF SUMMARY OF THE INVENTION
[0007] In view of the foregoing, it is an object of the present disclosure to provide a method and apparatus for timing.
[0008] A first exemplary embodiment of the present disclosure provides an apparatus for timing. The apparatus includes a frame, the frame having a top portion and a bottom portion, the top portion having a needle bar channel, and a spacer, the spacer moveable relative to the frame to overlay a portion of the top portion of the frame. The apparatus further including a clasping element connected to the frame and operable to change an effective diameter of a portion of the channel, and a bottom plate, the bottom plate connected to the bottom portion of the frame.
[0009] A second exemplary embodiment of the present disclosure provides a method for timing. The method includes affixing a frame to a needle bar of a sewing head, the frame defining a needle bar channel and having a clasping element, a spacer, and a bottom plate, the needle bar channel cooperating with the clasping element operable to removeably affix the frame to the needle bar. The method further including positioning the needle bar with the affixed frame such that the bottom plate aligns with a needle point hook height, and rotating a hook point such that the hook point is in contact with the bottom plate.
[0010] A third exemplary embodiment of the present disclosure provides an apparatus for setting hook timing in a sewing machine having a needle bar and a hook. The apparatus includes a frame adapted to releasably mount relative to a sewing machine needle bar, and a needle height setting spacer movably connected to the frame between a spacing position and a retracted position. The apparatus further includes a hook angular displacement block connected to the frame to define an angular displacement fixing position.
[0011] The following will describe embodiments of the present disclosure, but it should be appreciated that the present disclosure is not limited to the described embodiments and various modifications of the disclosure are possible without departing from the basic principle. The scope of the present disclosure is therefore to be determined solely by the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0012] FIG. 1 presents a perspective view of an exemplary device suitable for use in practicing exemplary embodiments of this disclosure.
[0013] FIG. 2 presents a perspective view of an exemplary device and a sewing head for use in practicing exemplary embodiments of this disclosure.
[0014] FIG. 3 presents a close-up view of an exemplary device and a sewing head for use in practicing exemplary embodiments of this disclosure.
[0015] FIGS. 4 a , 4 b , 4 c , 4 d , and 4 e in combination present stages of an exemplary rotation cycle for a hook point and a reciprocating cycle of a reciprocating needle for stitching in a quilting or sewing machine.
[0016] FIG. 5 presents an exemplary logic flow diagram in accordance with a method for practicing exemplary embodiments of this disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Prior to quilting or sewing with a quilting machine or sewing machine it is often required that a user adjust the bobbin hook or hook point such that the cycle of its rotation during use aligns with the reciprocating cycle of the reciprocating needle of the sewing or quilting machine so that the hook point can properly grab thread from the reciprocating needle. In other words, the scarf of the reciprocating needle during the upward motion portion of the reciprocating needle cycle needs to align with the hook point such that the hook point can obtain or displace thread from the reciprocating needle.
[0018] The process for aligning the reciprocating needle scarf with the hook point is quite time consuming and cumbersome because users typically adjust the hook point manually by visually determining the distance between the reciprocating needle and the hook point to see when and where the hook point should be affixed to the sewing machine.
[0019] Accordingly, there is a need for a simpler more accurate mechanism to align the reciprocating needle with the hook point of a quilting or sewing machine such that the timing of the rotation cycle of the hook point is properly aligned with the reciprocating cycle of the reciprocating needle to allow for proper stitching.
[0020] Embodiments of the present disclosure provide an apparatus and method of using a device with a quilting or sewing machine such that a user can more easily and accurately align a reciprocating needle of a quilting or sewing machine with the hook point such that the user can properly operate the quilting or sewing machine.
[0021] FIGS. 4 a , 4 b , 4 c , 4 d , and 4 e in combination present stages of an exemplary rotation cycle for a hook point and a reciprocating cycle of a reciprocating needle for stitching in a quilting or sewing machine. In FIG. 4 a , depicted is a reciprocating needle 402 with thread 404 , a hook point 406 with thread 408 , and a work piece 410 . In FIG. 4 a reciprocating needle 402 is not at the bottom of its reciprocating cycle, but has moved slightly above the bottom of its reciprocating cycle. Reciprocating needle 402 in FIG. 4 a is moving upward in its reciprocating cycle. The hook point 406 is near the 12 o'clock position and is in contact with thread 404 and grapping thread 404 from reciprocating needle 402 . The distance between the bottom of the reciprocating cycle of the reciprocating needle 402 and the point at which hook point 406 grabs or hooks thread 404 as shown in FIG. 4 a will be referred to as the needle hook point height. The position of the hook point 406 in its rotation cycle at which it can grab thread 404 from reciprocating needle 402 will be referred to as hook timing.
[0022] Turning to FIG. 4 b , the reciprocating needle 402 has moved further in the upward portion of its reciprocating cycle partially through work piece 410 . The hook point 406 has rotated towards the left in order to create a stitch between thread 404 and thread 408 .
[0023] Referring to FIG. 4 c , the reciprocating needle 402 is at the highest point of its reciprocating cycle and it is no longer in contact with work piece 410 . The hook point 406 has also continued to rotate in a counter-clockwise fashion to complete the stitch and is located at the 6 o'clock position. It should be noted that embodiments of the present disclosure include a hook point 406 rotating in either a clockwise or counter-clockwise fashion.
[0024] Reference is now made to FIG. 4 d , shown is reciprocating needle 402 beginning its downward portion of its reciprocating cycle moving closer to work piece 410 and hook point 406 . Hook point 406 has continued to rotate about its center now moving towards reciprocating needle 402 .
[0025] In FIG. 4 e , reciprocating needle 402 has pierced work piece 410 and is continuing to move in a downward motion towards hook point 406 . Hook point 406 has continued to rotate in a count-clockwise fashion towards reciprocating needle 402 . Once reciprocating needle 402 has reached the bottom of its reciprocating cycle and begun it upward movement, hook point 406 will contact thread 404 maintained by reciprocating needle 402 as shown in FIG. 4 a and the process or cycle for both the reciprocating needle 402 and hook point 406 will repeat.
[0026] Reference is now made to FIG. 1 , which depicts a perspective view of an exemplary device suitable for use in practicing exemplary embodiments of this disclosure. Shown in FIG. 1 is device 102 for properly setting a hook point or hook timing on a quilting or sewing machine. Device 102 includes a frame 104 , a clasping element 106 , a spacer 108 (or needle height setting spacer), and a bottom plate 110 (or hook angular displacement block).
[0027] The frame 104 as depicted is U-shaped, however, embodiments of frame 104 also include C-shaped or V-shaped configurations. Frame 104 is rigid and can be made out of any type of metal, plastic, wood or composite that will provide a rigid structure. Frame 104 includes a channel or needle bar channel 112 spaced to fit a needle bar of a quilting or sewing machine.
[0028] Clasping element 106 is moveably affixed to frame 104 . As shown in FIG. 1 , clasping element 106 includes a screw 112 extending through frame 104 , which when rotated by clasping element 106 can change an effective diameter of a portion of channel 112 . Embodiments of clasping element 106 include any type of clamping, clasping, gripping, or attachment mechanism known in the art such that frame 104 through channel 112 can be removeably affixed to a needle bar of a quilting or sewing machine.
[0029] Spacer 108 is rotatably affixed to the top of frame 104 such that it can rotate into a position that overlays a portion of the top of frame 104 without covering channel 112 . Spacer 108 can also rotate into a position that does not overlay a portion of the top of frame 104 . Embodiments of spacer 108 have a thickness equal to the needle hook point height. It should be appreciated that the thickness of spacer 108 can vary between different types or brands of quilting or sewing machines due to the differences in needle hook point height for that particular brand, make or model.
[0030] Bottom plate 110 is affixed to the bottom of frame 104 such that its long axis is perpendicular to frame 104 . Embodiments of bottom plate 110 in combination with frame 104 are sized such that when frame 104 is affixed at channel 112 with clasping element 106 to a needle bar of a quilting or sewing machine replicate or simulate the length and location of a reciprocating needle attached to the needle bar located at the needle hook point height. Embodiments of bottom plate 110 include bottom plate 110 being both fixedly attached to frame 104 or rotateably attached to frame 104 . Embodiments of bottom plate 110 include the long sides of bottom plate 110 having multiple grooves for receiving or contacting a hook point.
[0031] Reference is now made to FIG. 2 , which illustrates a perspective view of an exemplary device and a sewing head for use in practicing exemplary embodiments of this disclosure. Shown in FIG. 2 is device 102 and sewing head 202 . Sewing head 202 includes a needle bar 204 for maintaining a reciprocating needle for stitching. However, as depicted in FIG. 2 , needle bar 204 does not contain a reciprocating needle. Also, depicted in FIG. 2 is the bottom portion 206 of the sewing head for maintaining a hook point. Device 102 as depicted in FIG. 2 , is removably attached to needle bar 204 through channel 112 and clasping element 106 .
[0032] Referring to FIG. 3 , shown is a close-up view of an exemplary device and a sewing head for use in practicing exemplary embodiments of this disclosure. Shown in FIG. 3 is sewing head 202 with needle bar 204 and device 102 . As depicted in FIG. 3 , device 102 is removably attached to needle bar 204 at channel 112 with clasping element 106 . Also, shown in FIG. 3 is the bottom of sewing head 302 . In FIG. 3 , spacer 108 is in contact with bottom of sewing head 302 .
[0033] Needle bar 204 is able to move up and down thereby controlling the reciprocating cycle of a reciprocating needle maintained by needle bar 204 . Device 102 is able to move up and down with needle bar 204 when attached to needle bar 204 .
[0034] Reference is now made to FIG. 5 , which presents an exemplary process for using device 104 with a quilting or sewing machine to properly set or align the hook timing. The process begins at block 502 which states position a needle bar in the down position. Then at block 504 a hook timing device (e.g., device 102 ) is affixed to the needle bar such that the spacer is in contact with the bottom of the sewing head. Next at block 506 , the process continues rotating the spacer such that it is no longer overlaying the frame of the hook timing device and the needle bar is free to move up.
[0035] Then at block 508 the process continues with raising the needle bar until the bottom of the sewing head is in contact with the frame of the hook timing device. At this point, the bottom plate of the hook timing device is aligned with the location of where a reciprocating needle would contact the hook point. Accordingly, the length of embodiments of hook timing device (e.g, device 102 ) is sized such that it is equal to the needle hook point height. Then at block 510 , an unattached hook point is rotated until it comes into contact with the bottom plate of the hook timing device. Then at block 512 , the hook point is affixed to the sewing/quilting machine and the hook point timing device is removed from the needle bar.
[0036] It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used alone, or in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. The presently disclosed embodiments are therefore considered in all respects to be illustrative. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of this disclosure, which is defined in the accompanying claims.
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Presented is an apparatus and method for hook timing. An exemplary apparatus includes a frame, the frame having a top portion and a bottom portion, the top portion having a needle bar channel, and a spacer, the spacer moveable relative to the frame to overlay a portion of the top portion of the frame. The apparatus further including a clasping element connected to the frame and operable to change an effective diameter of a portion of the channel, and a bottom plate, the bottom plate connected to the bottom portion of the frame.
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RELATED APPLICATION(S)
This application claims the benefit under 35 U.S.C. §119(e) of Korean Patent Application No. 10-2005-0133165, filed Dec. 29, 2005, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to a CMOS image sensor, and more particularly, to a CMOS image sensor for controlling the saturation state of a floating diffusion region according to the degree of luminance.
BACKGROUND OF THE INVENTION
In general, an image sensor is a semiconductor device for converting optical images into electric signals and is mainly classified as a charge coupled device (CCD) image sensor or a CMOS image sensor.
However, a CCD has a complicated driving manner, high power consumption, and requires a multi-step photo process, which makes the manufacturing process thereof complicated.
For this reason, a CMOS image sensor has recently been spotlighted as the next-generation image sensor capable of overcoming the defects of the charge coupled device.
A CMOS image sensor is a device employing a switching mode to sequentially detect an output of photodiodes by providing MOS transistors corresponding to each unit pixel in conjunction with peripheral devices, such as a control circuit and a signal processing circuit.
That is, a CMOS image sensor with a photodiode and a MOS transistor within each pixel sequentially detects the electric signals of each unit pixel in a switching scheme to realize an image.
Since a CMOS image sensor is manufactured by utilizing CMOS technology, it has the advantage of relatively low power consumption. In addition, since a smaller number of photolithography steps is required, the manufacturing process of a CMOS image sensor can be simplified.
Further, since a control circuit, a signal processing circuit, an analog/digital converting circuit, and the like can be integrated on a single CMOS image sensor chip, the CMOS image sensor can minimize the size of a product.
Accordingly, a CMOS image sensor is widely used in various applications including digital still cameras, and digital video cameras.
CMOS image sensors are classified as a 3T type CMOS image sensor, a 4T type CMOS image sensor, or a 5T type CMOS image sensor according to the number of transistors formed in each unit pixel. The 3T type CMOS image sensor includes one photodiode and three transistors, and the 4T type CMOS image sensor includes one photodiode and four transistors.
FIG. 1 is an equivalent circuit diagram of a conventional 4T type CMOS image sensor, and FIG. 2 is a layout illustrating a unit pixel of the 4T type CMOS image sensor.
As illustrated in FIGS. 1 and 2 , the unit pixel of the CMOS image sensor includes a photodiode 10 and four transistors. In particular, the unit pixel includes a photodiode 10 for receiving light and generating electrons formed at the wide region of the active area; a transfer transistor 20 for transferring electrons collected at the photodiode (PD) 10 to a floating diffusion (FD) region; a reset transistor 30 for setting electric potential at the floating diffusion (FD) region to a desired value and for exhausting electric potential to reset the floating diffusion (FD) region; a source follow transistor 40 functioning as a source follow buffer amplifier; and a select transistor 50 functioning as a switch for addressing.
Furthermore, as shown in FIG. 1 , a load transistor 60 is formed at an output terminal (Vout) of each unit pixel 100 to read an output signal.
Referring to FIG. 1 , Tx is a gate voltage applied to the transfer transistor 20 , Rx is a gate voltage applied to the reset transistor 30 , Dx is a gate voltage applied to the source follow transistor 40 , and Sx is a gate voltage applied to the select transistor 50 .
FIG. 3 is a cross-sectional view of the CMOS image sensor taken along the line II-II′ illustrated in FIG. 2 .
Referring to FIG. 3 , the CMOS image sensor includes an isolation layer 62 formed at an isolation region of a semiconductor substrate 61 on which the active area and the isolation region are defined; a gate electrode 64 formed on a predetermined area of the active area of the semiconductor substrate 61 isolated by the isolation layer 62 with a gate insulating layer 63 formed therebetween; a photodiode region 65 formed in an upper portion of the semiconductor substrate 61 at one side of the gate electrode 64 ; a floating diffusion region 66 formed in an upper portion of the semiconductor substrate 61 at the other side of the gate electrode 64 ; and an insulating layer sidewall 67 formed at both sides of the gate electrode 64 .
FIG. 4 illustrates the operation of the transfer transistor shown in FIG. 3 .
Referring to FIG. 4 , the amount of responsive light may be determined by means of the capacitance of the photodiode (PD) region 65 and the capacitance of the floating diffusion (PD) region 66 .
When the amount of an incident light through the photodiode (PD) region 65 is large enough, the floating diffusion (FD) region 66 can saturate and no more reaction proceeds. When the amount of the incident light is too small, the amount of the generated electrons (e) is too small and a sufficient reaction does not occur.
BRIEF SUMMARY
An embodiment of the present invention can provide a CMOS image sensor utilizing a transfer transistor incorporating a finger type gate electrode.
According to embodiments of the CMOS image sensor of the present invention, a floating diffusion region can be formed between photodiode regions to prevent the saturation of the floating diffusion region and to improve the reliability of the operation.
Accordingly, there is provided a CMOS image sensor comprising first and second photodiode regions for generating electrons in response to incident light and a transfer transistor for receiving the generated electrons transferred from the first and/or second photodiode. In addition, the transfer transistor can be positioned between the first and second photodiodes.
In the preferred embodiment of the present invention, the transfer transistor can be a finger type transistor.
According to the preferred embodiment of the present invention, the transfer transistor can be a finger type transistor having a first gate electrode and a second gate electrode.
In a further preferred embodiment, a floating diffusion region can be provided between the first electrode and the second gate electrode.
In addition, the first gate electrode can be adjacent to the first photodiode and the second gate electrode can be adjacent to the second photodiode in the preferred embodiment of the present invention.
The channel length of the first gate electrode and the channel length of the second gate electrode can be different lengths in a preferred embodiment of the present invention.
According to embodiments of the present invention, a high voltage can be applied to the first and second gate electrodes to turn on the first and second gate electrodes when a low luminance is applied, and a low voltage can be applied to the first and second gate electrodes to turn on the first gate electrode and to turn off the second gate electrode when a high luminance is applied.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an equivalent circuit diagram of the conventional 4T type CMOS image sensor;
FIG. 2 is a layout diagram illustrating a unit pixel of the conventional 4T type CMOS image sensor;
FIG. 3 is a cross-sectional view of the CMOS image sensor taken along the line II-II′ of FIG. 2 ;
FIG. 4 illustrates the operation of a transfer transistor for the conventional CMOS image sensor;
FIG. 5 is a layout of a unit pixel of a 4T type CMOS image sensor according to an embodiment of the present invention;
FIG. 6 is a cross-sectional view taken along the line VI-VI′ of FIG. 5 according to an embodiment of the present invention;
FIGS. 7A-7D are cross-sectional views for illustrating the method of manufacturing the CMOS image sensor according to an embodiment of the present invention; and
FIGS. 8A and 8B illustrate the operation of the transfer transistor of the CMOS image sensor according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the CMOS image sensor according to preferred embodiments of the present invention and the method of manufacturing the same will be described in detail referring to the attached drawings.
FIG. 5 is a layout for illustrating the unit pixel of a 4T type CMOS image sensor according to an embodiment of the present invention, and FIG. 6 is a cross-sectional view taken along the line VI-VI′ of FIG. 5 .
In FIGS. 5 and 6 , the drawings illustrate the structure of the transfer transistor of the finger type suggested in an embodiment of the present invention.
As illustrated in the drawings, an isolation layer 102 for defining an active area and an isolation region can be formed on a semiconductor substrate 101 .
On the active area of the semiconductor substrate 101 , first and second gate electrodes 104 a and 104 b can be formed on a gate insulating layer 103 . That is, a finger type gate electrode can be formed.
The region of semiconductor substrate 101 between the first and second gate electrodes 104 a and 104 b can correspond to a floating diffusion region 109 .
The regions of semiconductor substrate 101 at the left and right sides of the first and second gate electrodes 104 a and 104 b can correspond to photodiode regions 106 a and 106 b.
Referring to FIG. 6 , an insulating layer sidewall 107 can be formed at both sides of the first and the second gate electrode 104 a and 104 b.
In a specific embodiment, the channel length of the first and second gate electrodes 104 a and 104 b can be formed to be different from each other.
As illustrated in FIG. 5 , one terminal portion of the first and second gate electrodes 104 a and 104 b can be electrically connected to form a finger type structure.
FIGS. 7A-7D are cross-sectional views for illustrating the method of manufacturing the CMOS image sensor according to an embodiment of the present invention. Particularly, a method of manufacturing a transfer transistor of a finger type is illustrated in these drawings.
Referring to FIG. 7A , an isolation layer 102 can be formed to isolate devices on a semiconductor substrate 101 .
Then, a gate insulating layer 103 and a conductive layer (for example, a high concentration poly-silicon layer) can be successively deposited on the whole surface of the semiconductor substrate 101 including the isolation layer 102 .
Here, the gate insulating layer 103 can be formed by a thermal oxidation process or a CVD method.
After that, the conductive layer and the gate insulating layer 103 can be selectively removed to form a gate electrode for each transistor.
The gate electrode of the transfer transistor can be formed as a finger type. In particular, first and second gate electrodes 104 a and 104 b can be formed with a constant interval in between the finger sections while crossing an active region of the semiconductor substrate 101 as illustrated in FIG. 7A . In a preferred embodiment, the fingers 104 a and 104 b can be formed with different channel lengths.
In a specific embodiment, the channel length of the second gate electrode 104 b can be twice as long as the channel length of the first gate electrode 104 a.
According to an embodiment of the present invention, the applied voltage onto the first and second gate electrodes 104 a and 104 b can be different from each other. In a specific embodiment, the transfer transistor can be selectively turned on by applying a high voltage when the light is weak and applying a low voltage when the light is strong.
In addition, output signals can be amplified respectively to different gain according to the applied voltage to the transfer transistor.
One terminal of the first and second gate electrodes 104 a and 104 b can be electrically connected and can have a finger type structure as illustrated in FIG. 5 .
Referring to FIG. 7B , a first photoresist pattern 105 can be formed by coating a photoresist on the whole surface of the semiconductor substrate 101 , including the first and second gate electrodes 104 a and 104 b , and then performing an exposing process and a developing process to cover the semiconductor substrate 101 between the first gate electrode 104 a and the second gate electrode 104 b.
First and second photodiode regions 106 a and 106 b can be formed by implanting low concentration n-type impurity ions into the exposed active area of the semiconductor substrate 101 using the first photoresist pattern 105 as a mask.
Here, the first and second photodiode regions 106 a and 106 b can be formed outside of the first and second gate electrodes 104 a and 104 b , other than the region between the first and second gate electrodes 104 a and 104 b.
Referring to FIG. 7C , the first photoresist pattern 105 can be completely removed and an insulating layer can be formed on the whole surface of the semiconductor substrate 101 .
In a specific embodiment, the insulating layer can be formed as a single layer or an integrated layer of a nitride layer and a TEOS oxide layer.
Subsequently, an anisotropic etching (RIE) can be performed to form an insulating layer sidewall 107 at both sides of the first and second gate electrodes 104 a and 104 b.
Next, a second photoresist pattern 108 can be formed by coating a photoresist on the whole surface of the semiconductor substrate 101 including the insulating layer sidewalls 107 , and then performing an exposing and developing process to expose the source/drain region of each transistor.
A source/drain impurity region can be formed by implanting high concentration n+ type impurity ions into the exposed source/drain region using the second photoresist pattern 108 as a mask.
At this time a floating diffusion region 109 , which is a drain impurity region of the transfer transistor, can be formed at the active area between the first gate electrode 104 a and the second gate electrode 104 b.
That is, the floating diffusion region 109 can be formed between the first and second photodiode regions 106 a and 106 b according to an embodiment of the present invention.
Referring to FIG. 7D , the second photoresist pattern 108 can be removed. Then, an annealing process can be performed to diffuse various impurity ions implanted into the semiconductor substrate 101 .
FIGS. 5A and 8B illustrate the operation of the transfer transistor constituting the CMOS image sensor according to embodiments of the present invention.
The CMOS image sensor described in FIGS. 5A and 5B can incorporate first and second gate electrodes 104 a and 104 b formed on a semiconductor substrate and separated by a predetermined interval. The first and second gate electrodes 104 a and 104 b of a transfer transistor can be finger type. A floating diffusion region (FD) 109 can be formed at an upper portion of the semiconductor substrate 101 between the first and second gate electrodes 104 a and 104 b.
In addition, first and second photodiode regions 106 a and 106 b can be formed at both sides of the floating diffusion region 109 .
Accordingly, the gate electrode of the transfer transistor in the CMOS image sensor of an embodiment of the present invention can be formed as a finger type and the photodiode region can be divided into two photodiode regions. A floating diffusion region can be formed between the divided photodiode regions to improve the reaction at a low luminance and at a high luminance.
Referring to FIG. 5A , both the first and second gate electrodes 104 a and 104 b can be turned on by applying a high voltage at a low luminance. Therefore, the floating diffusion region (FD) 109 can receive all the electrons generated at the first and second photodiode regions 106 a and 106 b.
Referring to FIG. 8B , only the first gate electrode 104 a is turned on by applying a low voltage at the high luminance when a sufficient light is applied. Therefore, the floating diffusion region (FD) 109 only receives the electrons generated at the first photodiode region 106 a to generate corresponding electric signals.
That is, under a low luminance, both the first and second photodiode regions 106 a and 106 b can be utilized to improve the sensitivity in an embodiment of the present invention. In addition, under a high luminance of a large amount of light, only the first photodiode region 106 a may be utilized. Accordingly, the saturation phenomenon of the floating diffusion region can be prevented.
As described in detail above, the CMOS image sensor and the method of manufacturing the same according to embodiments of the present invention can provide the following characteristics.
First, the gate electrode of the transfer transistor can be formed as a finger type and the photodiode region can be divided into two photodiode regions. Between the divided photodiode regions, a floating diffusion region can be formed to improve the reaction at a low luminance and at a high luminance.
Second, since the saturation level at the floating diffusion region can be heightened, the operation at a large amount of light is possible, and the operation range improves.
Although a preferred embodiment of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
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Disclosed is a CMOS image sensor including a gate electrode of a finger type transfer transistor for controlling the saturation state of a floating diffusion region according to the luminance level (i.e. low luminance or high luminance). The CMOS image sensor includes first and second photodiode regions for generating electrons in response to incident light, and a transfer transistor positioned between the first and second photodiodes for receiving the generated electrons transferred from the first and/or second photodiode.
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BACKGROUND OF THE INVENTION
1) Field of the Invention
The invention relates to a device for realizing a cooling effect in a space, for instance an accommodation area, an office space, a living room or a cab in a means of transport such as a car, a boat or an aircraft.
2) Description of the Related Art
Such a device is known in many embodiments.
Cooling devices for cooling the air in a space are characterized by a substantial air displacement. Particularly the sensation of being exposed to a cold airflow is often perceived as unpleasant.
The operating principle of existing cooling devices is however based on air displacement, so that the problem of exposure to a cold airflow and the corresponding sense of lack of comfort are inherent in the solution. Most used air-conditioning systems have in addition a number of generally known drawbacks: they are heavy, they consume a great deal of energy, they make use of environmentally impacting substances and often spread environmentally impacting substances. In addition, the most usual cooling devices can be adjusted to a very great difference between the indoor temperature in the relevant space and the outdoor temperature, which can cause disorders such as colds and headache. It is generally better advised to keep to a difference of a maximum 4 to 5° C. between the indoor air and the outdoor air. Air which is possibly too dry can further cause disorders such as headache, a dry throat, coughing or irritated eyes, and contaminated filters can also cause physical disorders through lack of sufficient maintenance.
SUMMARY OF THE INVENTION
It is a first object of the invention to provide a cooling device which is highly energy-efficient, does not comprise or emit any environmentally-impacting, let alone harmful substances, has a low weight, can be installed very simply and does not causes any cold and uncomfortable airflows.
A further object of the invention is to embody a cooling device such that it is suitable for application in fixed stationary spaces, for instance in a building, as well as in moving spaces, for instance in means of transport.
Different cooling methods are known which stand out in their environmental friendliness and high energy efficiency. An important option in this respect is the evaporation cooler which in some conditions can even be embodied as dewpoint cooler.
The principle of the evaporation cooler is also used by the physical mechanisms of the human body. At a high ambient temperature perspiration occurs which can be evaporated by passing air, thereby causing a considerable decrease in temperature locally and so extracting heat from the skin. This effect occurs more noticeably in the case of more actively evaporating liquids such as methanol, ethanol or the like. If this liquid is applied to the skin, the relevant location feels cold because a great deal of heat is extracted from the skin as a result of evaporation of the liquid.
The same principle is used in the so-called water bag or a somewhat porous stone pitcher. The water bag or the pitcher, the wall of which is slightly moisture-permeable, is suspended in the wind. The water seeping through evaporates on the outside and thus extracts heat from the water in the bag. Particularly in desert regions this is a tried and tested method of keeping water cool. This principle has been applied since time immemorial.
More recent and modern applications can be found in air-conditioning installations for buildings and for instance campers, these systems making use of evaporation of water and the associated heat extraction. Water is here evaporated on the one side of a heat exchanger under the influence of a first airflow, and on the other side a second airflow is cooled on the heat exchanger and subsequently distributed via a conduit system for instance through the cab of the camper, or even a building. The second airflow can for instance be a partial flow of said first or primary airflow. The drawback of the clearly perceptible, substantial cold airflow hereby remains fully in evidence. It must however be acknowledged that there are no harmful substances in the case of such an evaporation cooler, and the device can operate at a very low energy consumption, i.e. no more than the energy necessary to generate and maintain the airflow.
There are also many cooling devices which do not make use of a substantial secondary airflow. The best-known example is the generally known refrigerator found in almost every Western household. Situated usually at the rear of the refrigerator is a heat exchanger which generates heat to the ambient air. By using a two-phase coolant and a compressor this heat is extracted from a cooling wall on the inside of the refrigerator. Such devices also exist on larger scale, for instance cooling installations with cooling plates in trucks intended for the purpose of refrigerated transport of perishable cargo. While these devices do operate without forced secondary airflow, they make use of a coolant, usually a freon, and are thermally not very efficient, or use a large amount of energy.
It is known that cooling by means of radiation absorption is perceived by people as being very pleasant. There are many examples of radiation-absorbing coolers, such as for instance buildings provided with concrete core activation, wherein conduits received in the floor and the floor above, i.e. the ceiling, are supplied with cold or hot water in order to provide for respectively absorption or emission of radiation, and also cooling ceilings, metal ceiling plates provided with meandering water conduits through which cold water is also carried for cooling purposes. A great advantage of this cooling method is that—in contrast to more conventional methods of cooling by means of cold airflows—they are not very sensitive to the necessary ventilation and the resulting disappearance of the cooling to the outside.
In order to obtain a comfortable effect from these radiation absorbers the difference between radiation temperature and space temperature must remain within limits. According to Fanger models and general professional practice, a difference of 5° is a guideline for the limit of comfort. This means that the cooling capacity in respect of convection or actual air-cooling capacity of these solutions is quite limited: the difference in generated radiation between a plate of 1 m 2 of 27° C. and one of 24.5° C. is q=σ (T 2 4 −T 1 4 ), in which T is the temperature in Kelvin and σ the Stefan-Boltzmann constant is only 15 W. The effective cooling capacity in terms of convection is hereby negligible.
In so-called cooling ceilings a value is generally employed of about 60-70 W per m 2 . This value is however difficult to realize in buildings in summary conditions because the temperature of a ceiling plate for the purpose of obtaining such a cooling capacity will be lower than the dewpoint in the prevailing conditions, with the result of condensation on the user side of the ceiling plate. This may then result in falling droplets, something which is a highly undesirable in many circumstances.
In the above described methods there is cooling from outside: a cold-generating agent (usually water) is supplied from outside and also discharged again to the outside and there recooled or at least made suitable for use for the cooling of the radiation absorber.
An alternative hereto are electrical cooling elements such as Peltier elements. Very interesting embodiments of a radiation absorber provided with Peltier elements are disclosed in EP-A-432 264 and WO-A-90/00240, wherein a radiation-absorbing wall in very close vicinity to the human user is proposed provided with electrical cooling elements which generate the absorbed heat on the inside of the hollow wall, where this heat is discharged upward by natural convection or mechanical ventilation. A small intermediate ceiling prevents the user of the space between preferably two of these walls, perhaps for the purpose of the radiation symmetry, once again being confronted with the discharged heat.
Electrical coolers do not of course have an efficiency of 100%, which means that on balance the space temperature will rise as a result of this solution, certainly when the efficiency of a fan must also be included in the calculation. While there is in the first instance a cooling effect discernible to the user, the air temperature does eventually increase.
Other systems are also known in which the cooling element is not placed in the upper part of the space but is disposed freely in the space for cooling, for instance as according to DE-A-1 012 381.
While it is not explicitly stated here what the source of the cooling itself is, the flow of air makes it fairly clear that what is involved is cold “from outside”. For proper operation there is even a heat exchanger, which makes it wholly clear that heat (or cold) from outside is involved.
It would perhaps be advantageous to place such a device close to the user, but no mention is made of this in the specification.
A drawback to the solution is that also at locations (the side directed toward the ceiling) of the proposed relatively high solution, a large part of the radiation absorption will be provided at a relatively unfavourable location: the ceiling of the space, whereby no advantage is provided for the view angle of cold for the user present under the proposed cooler disposed lower in the space. This second wall, directed toward the ceiling, therefore has no effect for a possible direct user of the cooling.
As already stated above, other cooling methods have long been known for obviating the problem of the discharge of energy. The oldest is perhaps the human skin: causing transpiration moisture to evaporate from the skin results in direct cooling of the skin surface, a not insignificant means of cooling the human body. This is applied in particularly interesting manner in GB-A-1 937 041 and GB-A-464 415, wherein a cooling of a cargo of a truck is proposed which is similar to the action of sweat on the skin. Provided there is no problem caused by the condensation already referred to above, this is an excellent solution: if a very large amount of water is evaporated in a very large airflow, considerable cooling capacity is then obtained. If this must be transferred by means of a relatively extensive but flat surface such as the ceiling of a loading space of a truck, this will then quickly result in limitations. If the air moves in the loading space only as a result of convection, condensation will then occur quickly. This need not be a limitation per se, but does become so in circumstances where people have to be cooled. They will perceive falling droplets as unacceptable. If a second airflow is also brought about in the loading space of the vehicle, the temperature will indeed then fall to some extent, but probably much too little to keep for instance slaughtered meat to temperature. This is therefore a very limited application. The temperature of the heat-exchanging ceiling plate will moreover not fall below the dewpoint temperature, although the capacity will be considerable at very high air speeds in the cooling part. The comfort principle is then still applicable: much more than the guideline of 5° C. temperature difference between ambient temperature and radiation temperature will usually be perceived by people as unpleasant.
It could be contended that these methods stand up well for the cooling of people: when applied in a bus as according to U.S. Pat. No. 2,552,819, the system could be set very low so as not to cool the space but to cool only the passengers by absorbing their radiation. Air from outside is still used however, and condensation will still occur easily on the inside, for instance because the air humidity in the bus increases rapidly due to moist clothing and/or the transpiration moisture of the passengers.
The invention has for its object to improve in an extremely energy-efficient manner the sensation of comfort of a person by means of a combination of evaporation cooling and radiation absorption.
The device according to the invention comprises for this purpose
a housing with a heat-conducting wall, which housing bounds a chamber through which air can flow;
an air inlet which connects to the chamber and to said space;
an air outlet connecting to the chamber;
air transport means, for instance fan means, for transporting air from the air inlet via the chamber to the air outlet; and
moistening means for moistening the inner surface of said wall with an evaporable liquid, for instance water;
this such that air transported by the air transport means is introduced into the chamber via the air inlet, passes along the moistened inner surface of said wall in the chamber and is discharged from the chamber via the air outlet, whereby water present on the heat-conductive inner surface evaporates and is entrained by the air flowing by, and said wall is cooled.
We will first sketch an outline:
Taken as mathematical model is a fine summer day in the Netherlands:
The temperature amounts to 27° C., a good average value, as is that of the air humidity at about 78%.
With evaporation cooling the lowest achievable temperature of the air is 24.5° C. In terms of humidity the air is at that moment saturated: water no longer evaporates from the cooling element. In the most favourable conditions the temperature of the air in the space will not of course become lower than the maximum (minimum) achievable temperature. Much too little effect to cool cargo. This calculation shows that the method is wholly unsuitable for so-called process cooling.
The example of 24.5° C. as mentioned above is not therefore an arbitrary choice: on a fine summer day in the Netherlands no more can be achieved because of the dewpoint. This is comparable to water in a pan which is everywhere 100° C. when it boils and wherein the temperature rises only when the water has evaporated, unless the pressure is increased as in the case of a pressure cooker.
Suppose now however that an extensive surface is provided with a moisture-retaining a layer, this surface is arranged quite close to the user, a human or animal, in order to maximize the view angle:
It is then the case that:
If we assume that the human body dissipates on balance 70-100 W of energy via convection, conduction, evaporation via breathing and radiation; if we consider that a person loses 30-70% of his/her heat by means of radiation, wherein in warm conditions for instance half of 70-100% must be radiated via the skin, it can then be anticipated that the head, a relatively spherical shape, will have to lose much heat via radiation, bearing in mind that all radiation must leave the body via bare arms and head, assuming that the rest of the user is more or less clothed.
As mathematical model: a head, considered the ideal heat radiator with a diameter of φ20 cm, generates 58 W of heat at a skin temperature of 30° C. The head will of course also receive much radiation from the environment: walls, ceiling, trees and so on. Every body generates radiation, unless at the absolute zero point.
Continuing with the stated actual example of 27° C. and 78% relative air humidity.
If a double-walled evaporation cooler of 1 m 2 is arranged which is provided with a moisture-retaining layer with sufficient water on the inner side of the cooling side directed toward the user, it can then be calculated as already stated above in accordance with q=σ (T 2 4 −T 1 4 ) that the plate can absorb a radiation of 15 W. This is one quarter of the overall radiation emitted by a head. The head receives radiation from its overall environment as a result of the temperature of 27° C., so there is a strong sensation of comfort despite there not being a sensation of coolness since the difference in temperature between the radiant heat and the ambient temperature remains below 5° C. Nor is there a heat flow in respect of convection.
Suppose now that the evaporation cooler is embodied as a thin chamber, provided on the inner side of the side directed toward the user with a moistened, moisture-retaining side over which air drawn from the user space is carried at a speed which guarantees complete evaporation, it can then be calculated from the heat of evaporation of water (2258 kJ/1 or kJ/kg) that for 15 W or J/second cooling capacity only 24 grams of water per hour (3600 seconds) is necessary (15 J/s/2258000)/kg)×3600 seconds=0.0239 kg).
If—on the basis of the prevailing conditions of 27° C. and 78% relative air humidity—we now calculate that 24 grams of water are added to the air in one hour at the minimum ventilation of 20 m3 per hour per person, the air used for the evaporated water can then be added to the ambient air. This results in an increase in the relative air humidity of only about 2%, this not being significant.
The effect is in fact even more favourable: as a result of the evaporation of the water the temperature of the process air will hardly rise and, in favourable cases, even fall and the temperature of the space will thereby also fall again, this in contrast to for instance WO-A-90/00240.
In addition, a control for preventing condensation is no longer necessary: if the wall is kept no more than moist, it will then be understood that the wall never becomes colder than the prevailing dewpoint temperature. The action on the inner side then stops. Condensation therefore never occurs, because use is made of the air from the space, this in contrast to the other proposed solutions wherein use is made of air from a second space (the outside world) where the conditions may be wholly different. The system is hereby intrinsically free of condensation without any moisture sensor-related control needing to be applied.
If a choice is now also made for a very thin chamber, i.e. a chamber wherein the cold-absorbing side and the other side are very close together, for instance so-called channel plate, made for instance from polypropylene, and one side of the channels directed toward the extended side of the plate is provided on the inner side with an absorbent layer, the plate can thus just be filled with water occasionally or a droplet could be “blown” through each channel for the purpose of moistening the moisture-retaining layer. Air is then blown again through the channels which, as has been demonstrated above, can simply be added to the air in the user space. An outflow opening to the outside world is not necessary in the case of so little water vapour.
The cooler itself is then only a few millimeters thick.
This can of course also be achieved with for instance a metal plate having thereunder/thereabove a structure of channels having for instance a U-shape. This makes it possible to suffice with half the channels and places the inflow and outflow openings on the same side, which can be advantageous. The metal enhances the heat/cold conduction, although the outer walls of the channel plate are so thin that the insulating value of the plastic is not a major factor. A metal, for instance anodized aluminium plate, is aesthetically better and also more durable.
If this cooler, which is given a very thin form and is for instance provided on one side with a small supply tank of water and a very thin and therefore silent fan, is now suspended with the cooling wall facing downward, a ceiling island is now obtained which can also be provided with lighting. It is also very well possible to use the island as sound-damping panel.
When the cooler is placed above a table, the cooler also absorbs radiant heat from the tabletop, whereby the table becomes a more or less passive radiation cooler for the radiant heat emitted downward by the head. The effect is hereby enhanced to a significant extent because the view angle of the cooler suspended close-by relative to a regular cooled ceiling at greater distance is already sufficient and also has an added effect due to the absorption toward the tabletop. This advantage will of course also apply in the case of a usual cooled ceiling, since such a cooled ceiling also absorbs the radiant heat from a tabletop. The proposed cooler is however much more compact and only provides radiation absorption precisely where this is desired.
The thin version of the cooler can even be laid on the tabletop in similarly manner to a desk pad: the cooler then directly absorbs the downward generated radiant heat. With combined use of an upper and lower cooler this effect is of course much stronger. Side walls and a rear wall could optionally also be added, although the capacity then probably becomes too great and simplicity is lost.
The COP (the ratio of cooling capacity to power input) of an evaporation cooler based on water is very high because of the high heat of evaporation of water, roughly a factor of 10 higher than that of conventional cooling. The process air is not warmer, or hardly so, and in favourable conditions is even cooler than the inflowing air, and the process air can therefore be used as cooling air even though the capacity will be extremely low. Add to this that only radiant heat is taken into account, the energy consumption is then doubly advantageous: a high COP and a very low required cooling capacity as well as being wholly unsusceptible to airflow resulting from ventilation.
The invention provides an ideal cooler for modern houses which are very energy-efficient and where a home office becomes very warm. A pleasant workplace can be created using this cooler.
The cooler also provides a solution for instance in schools, where there is often no space for later inclusion of central air-conditioning; conventional compact air-conditioners have little effect here because of the high ventilation requirement.
The temperature of the system is controllable by modifying the strength of the airflow; very low air speeds result in a slower evaporation of the water, and thereby a smaller fall in temperature. The effect will of course be lost when water is no longer present in the moisture-retaining layer.
In a preferred embodiment the device has the special feature that the air outlet debouches outside the space for cooling. Such an embodiment prevents the moistened airflow, which entrains water vapour, increasing the relative humidity too substantially in the space for cooling, which can be perceived as unpleasant, although as already explained above the increase in the air humidity will be very limited in most conditions but can in determined conditions result in condensation.
According to yet another aspect of the invention, the device can have the feature that the wall is disposed at least more or less horizontally. Such an embodiment has the advantage that the device can adjust itself in substantially natural patterns to the lines and surfaces present in the space. The device can hereby become more or less optically inconspicuous in its surroundings, which may be preferred from an aesthetic viewpoint.
With a view to an efficient evaporation with the lowest possible flow rate of the throughflow air and in order to ensure that the device takes up the least possible space, the device can have the special feature that the housing is embodied as a hollow panel with a linear dimension transversely of the wall amounting to a maximum of 1/10, preferably 1/20 or, with the channel plate, perhaps even 1/30 to 1/50 of a representative linear dimension, for instance the length or the width of said wall.
This latter embodiment, particularly in combination with the above discussed aspect, can have the feature that the wall is disposed at least more or less horizontally, for instance is embodied as lowered ceiling panel. Practically and aesthetically this can be highly recommended.
It will be apparent that it is of the greatest importance that the air flowing by is able to evaporate water present on the inner surface of the wall with the highest possible efficiency in order to thus cool the wall. It is therefore recommended that the device is embodied such that said inner surface is embodied such that water disperses thereover without droplet formation.
In order to achieve this object the device can for instance have the feature that said inner surface is subjected beforehand to a corona treatment.
Alternatively, the device can be embodied such that said inner surface is provided with a hydrophilic cover layer.
In another embodiment the device can have the feature that said inner surface is provided with a porous cover layer, for instance of a cement such as Portland cement, or a fibrous mat. As fibre material for a mat it is possible to envisage for instance mineral fibres such as glass wool or rockwool. Synthetic fibres or natural fibres can also be applied.
In order to prevent the growth of fungi and algae and the accumulation of germs, an agent can for instance be added to the cover layer which combats these undesirable phenomena. The literature also suggests the possibility of providing the relevant surfaces with a cover layer of TiO 2 . Such a cover layer must be irradiated continuously, or at least with some regularity, with ultraviolet (UV) radiation. The TiO 2 acts as a catalyst, and the combination with ultraviolet radiation provides for a very strong germicidal action.
The moistening means can be embodied in any suitable manner. Recommended is an embodiment in which the moistening means comprise a number of drippers or sprayers.
In order to make the effectiveness of the device greater than is possible with a single, for instance flat wall, a specific embodiment of the device can have the special feature that means enlarging the heat conducting surface area, for instance fins, are added at least to the inner side and at least to a part of the heat conducting wall, said surface area-enlarging means being in direct thermal contact with the wall.
The device according to this latter embodiment can have the feature that the surface area-enlarging means are added to the inner surface of the wall. The outer surface thereby remains unaffected, while the cooling efficiency of the device can nevertheless be considerably improved. This aspect will therefore have the effect that the average temperature of the wall will fall considerably, which will further increase the efficiency, or COP (coefficient of performance). It is noted here that an air-conditioning device in for instance a car has a COP (the ratio of the effective cooling capacity to, usually electric, power input) which will be no greater than 2-3. For usual air-conditioning installations in fixed arrangements, so in houses, offices, factories and the like, a COP in the order of 3-6 is realized with the better, more modern installations. The evaporation cooler according to the invention, to the extent this is necessary, makes use of only an electric fan and the high heat of evaporation of water, without any form of compression of a two-phase medium being necessary. The COP can hereby be spectacularly higher than in the case of known air-conditioning, for instance 10-20, or even higher.
It must also be remembered here that the cooling device according to the invention operates substantially completely silently.
In a specific optional embodiment the device has the feature that the moistening means are only active in the upstream zone of the wall such that the air cooled in this zone cools the remaining downstream zone of the wall. If the process air in this first zone were to be wholly saturated with water, there is then still no danger of condensation in the downstream zone of the wall because this second zone will be warmer than the first and the solubility of water vapour in air increases as the temperature of the air rises.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be elucidated with reference to the accompanying drawings of two random exemplary embodiments.
In the drawings:
FIG. 1 shows a partially cut-away perspective view of the bodywork of a car provided with a cooling device with electric fans;
FIG. 2 shows a view corresponding to FIG. 1 of an embodiment which operates without electric fans but is based solely on an airflow which occurs during driving of the car;
FIG. 3 shows a view corresponding to FIGS. 1 and 2 of an embodiment which can operate on the basis of electric fans as well as on passing wind;
FIG. 4 shows a view corresponding to FIGS. 1, 2 and 3 , wherein a liquid-retaining layer with the associated moistening means is present only on the upstream side of the lower wall;
FIG. 5 shows a view corresponding to FIGS. 1-4 of an embodiment with a moisture-retaining layer with associated moistening means arranged only upstream, and provided downstream with surface area-enlarging means, in particular fins;
FIG. 6 shows a view corresponding to FIGS. 1-5 of an embodiment with provisions for the use of precipitation water;
FIG. 7 is a partially cut-away perspective view from the underside of a device according to the invention in the form of a ceiling panel for use in a room or similar space;
FIG. 8 is a partially cut-away perspective view from the top side of the device according to FIG. 7 ;
FIG. 9 shows a plastic channel plate greatly resembling for instance corrugated cardboard;
FIG. 10 shows a metal plate on which is arranged a plate with more or less U-shaped channels;
FIG. 11 shows a cooler according to the invention which is laid on a tabletop and provided with a water reservoir and fan; and
FIG. 12 is a partially cut-away view of cooler which can be used on a tabletop and is provided with a small axial fan and a droplet reservoir.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows the body 1 of a car with a cooling device 2 according to the invention. The cooling device is embodied as a shallow panel with an inner space 10 and is bounded on the top side by car roof 3 and on the underside by a horizontal wall 4 which, compared to usual cars, takes the place of the so-called roof lining. The inner surface of lower wall 4 is provided with a liquid-retaining layer 5 , consisting for instance of Portland cement or a thin layer of fibre material. The layer thicknesses can for instance be in the order of 0.1-0.3 mm. A suitable, easily evaporating liquid, for instance water, is fed to layer 5 by an arrangement of sprayers 6 which provide for a uniform moistening of layer 5 . The sprayers receive water via a conduit system (not shown) connected to a conduit 24 and a supply tank 22 with a filler cap 28 . Water can be fed under pressure intermittently, in accordance with requirement, to sprayers 6 by means of a simple pump 23 , for instance a pump of the type used to deliver windscreen washer fluid.
Arranged at a suitable location are fans 7 which blow air, indicated with arrows 8 , drawn only from the space 9 A inside the cab of the car through air inlet 8 A and through the hollow jambs 9 into chamber 10 such that the inblown air 8 flows over the moistened layer 5 and leaves device 2 at the rear through hollow jambs 9 as according to arrows 11 , and may be discharged through the air outlet 11 A back into the space 9 A or to the surrounding environment. The air entering the chamber ( 10 ) is untreated air from the space ( 9 A). As a result of a flow of non-saturated air flowing over the wet layer 5 the water present in this layer 5 evaporates, this having in a known manner a strong cooling effect. Wall 4 is hereby cooled. The wall 4 is facing the space 9 A, such that the space 9 A is subjected to radiation from the wall 4 .
A wall is thus placed in the vicinity of the head of the users which has a lower temperature than the air toward which it is directed, thereby creating a net radiation absorbing effect, moreover in the vicinity of the head, relatively the greatest radiator and certainly the most sensitive in respect of perception of cold and heat. In the shown embodiment the process air is discharged to the outside. The reason for this is that the space in the cab of a car is so limited that the air humidity can increase quickly here due to the water evaporated because of the cooling, and this can be unpleasant.
Fans 7 are placed as overpressure fans, therefore on the upstream side of device 2 . Alternatively, fans 7 could also be placed as underpressure or suction fans, and could therefore be disposed on the downstream side of device 2 .
FIG. 2 shows a variant in which the intake airflow 8 is not generated by fan means as in FIG. 1 , but via favourably placed outflow openings to the outside world 125 and 126 placed at a location in the outer side of the car where underpressure or a very high air speed prevails during driving, whereby the outflowing air 11 is suctioned away and airflow 8 is thereby drawn into chamber 10 . Situated on the rear side of chamber 10 are outlet openings 113 which can be opened and closed by means of flaps 125 operated by actuators 126 . The cooling device according to FIG. 2 will only function in the case of a substantial vehicle speed.
FIG. 3 shows an embodiment wherein use is made of both fans 7 and outflow openings 113 . The small fan in the middle jamb is omitted, while the airflow from the fan arranged on the front side of the vehicle nevertheless provides for airflow at that location. Fans 7 could otherwise be accommodated directly in lower wall 4 .
FIG. 4 shows an embodiment wherein the heat-conducting lower wall is provided with a water-dispersing and/or water-retaining layer, for instance a thin layer of Portland cement, over about half its length in the flow direction of the air from the intake side. The sprayers 6 are placed only in this zone. In the embodiment according to FIGS. 1, 2 and 3 these are placed distributed in a regular arrangement over the whole surface. The second half of the lower wall, warmer than the first half, can then reheat the throughfed, moistened and, in ideal conditions, cooled air, whereby the temperature of the second half of the lower plate decreases while the solubility of water vapour increases due to the raised air temperature, thereby decreasing the danger of condensation in chamber 10 .
FIG. 5 shows a variant of the embodiment according to FIG. 4 , wherein surface area-enlarging means 14 are arranged on the downstream side on the heat-conducting lower wall. Such fins can for instance be manufactured from a heat-conductive material such as copper or aluminium.
FIG. 6 shows an embodiment wherein precipitation, in particular rainwater, is collected via a receptacle 29 which drains into a reservoir 22 , which can moreover be provided with a filler cap, via a conduit 30 and via roof gutter 31 via a conduit 30 into for instance a second reservoir 22 which is also provided with a filler cap 28 with a pump 23 and a conduit 24 connecting to the conduit system (not shown) and sprayers 6 , wherein connecting conduit 32 supplies the water from roof gutter 31 on the other side.
The device according to FIG. 3 in a car can thus operate without external energy supply, or optionally with very low energy consumption, i.e. the optional consumption of fan means 7 . This creates additional possibilities: suppose that the car is parked in the sun and the roof were provided with photovoltaic panels. Such panels built into a roof of a car are for instance known from the German car manufacturer Audi. Audi supplies as option a sunroof which, with a sufficient irradiation by sunlight, powers an electric fan which ventilates the interior during parking, whereby the temperature in the interior increases less extremely than in the case of a non-ventilated cab. Such a known system does not in fact cool, it merely ventilates. If the electrical energy from the solar panel is now used in the configuration according to FIG. 1 in combination with device 2 , a cooling effect is realized with a fraction of the energy required for sluice ventilation. Cooling takes place at the position where it has the most effect, i.e. on the top side where, after people have got in, their heads are situated, so that these people feel the comfortable effect of radiation absorption.
It is noted that it is deemed useful in this application to insulate the inner surface of roof 3 of chamber 10 , for instance by means of a layer of expanded polystyrene foam. This prevents the cooling effect resulting from the operation of the cooling device being partially counteracted by too strong a heating under the influence of solar irradiation.
FIGS. 7 and 8 show a panel-like cooling device 15 according to the invention intended for instance for hanging on a ceiling of for recessed placing therein. Where applicable and useful, the same reference numerals are used in FIGS. 7 and 8 as in FIG. 1 .
Instead of a fan placed at distance, device 15 comprises two tangential fans 16 which have a small diameter and have a length amounting to about half the width of device 15 . For purposes of mechanical rigidity the device has two compartments separated from each other by a vertical dividing wall 17 . In the context of the invention this principle is more generally applicable in respect of the use of modularity.
On the blow-out side the upper wall 18 has two outlet slits 19 which debouch into respective plenum compartments 20 which discharge the cooled moistened air 11 via an outlet opening 21 , which debouches outside the user space for instance via a conduit. In an alternative embodiment (not shown) fans 16 could also be placed on the outlet side and air drawn in via plenum compartments 20 .
In a further alternative embodiment (not shown) the plenum compartments could be omitted, since the air which is moistened by evaporation of water and which has flowed through chamber 10 will under normal conditions have little effect on the relative air humidity in buildings.
This device could also be connected to the ventilation device or venting of a building or an optionally present solar chimney, wherein the whole extraction can take place completely passively on the basis of a thermosiphoning effect.
FIG. 9 shows a so-called channel plate 39 , a panel constructed from two plates with mutually parallel ribs therebetween, which displays a great similarity to corrugated cardboard and could be used as housing for the cooler in a similar manner as the housing of the cooler according to FIG. 7 and FIG. 8 .
Where applicable and useful, the same reference numerals are used in FIGS. 9, 10, 11 and 12 as in FIGS. 1-9 .
The lower plate 4 in the figure is provided on the side directed toward the inner side of the panel with a moisture-retaining layer 5 . The second plate of the channel plate forms the wall 18 . The intermediate ribs can be compared to the dividing wall 17 . Channel plates can for instance be obtained embodied in polymethyl methacrylate (PMMA), polycarbonate (PC) and polypropylene (PP). This latter embodiment is mainly very thin-walled. Usual embodiments weigh 300-500 gram per square meter at a panel thickness of 3-5 mm.
FIG. 10 shows a variant of the channel plate according to FIG. 9 . Lower plate 4 is now for instance a metal plate on which a second metal plate 40 is arranged with more or less U-shaped channels. A moisture-retaining layer 5 is arranged in the channels on the side of extended surface 4 directed toward second plate 40 .
The moisture-retaining layer 5 is moistened by first carrying the cooling medium, for instance water, as according to arrows 41 through the U-shaped channels and discharging it as according to arrows 42 . Air from the user space is then carried through the U-shaped channels as according to arrows 41 and discharged as according to arrows 42 .
FIG. 11 shows a cooler similar to that of FIGS. 8 and 9 which is laid on a tabletop 44 .
In contrast to the ceiling plate of FIGS. 8 and 9 , plate 4 now faces upward. Coolant, for instance water, is fed intermittently from water reservoir 43 to the channels of channel plate 39 as according to FIG. 9 in order to moisten the moisture-retaining layer 5 (not shown). The tangential fan 16 carries air through the channels of channel plate 39 so that plate 4 cools due to the extraction of heat of evaporation due to evaporation of the coolant.
FIG. 12 shows a partly cut-away view of a cooler similar to that of FIG. 11 , wherein an axial fan 48 blows air through channel plate 39 via a plenum compartment 47 . Plate 4 once again faces upward here.
Coolant, for instance water, drips via suitably dimensioned holes out of reservoir 45 into the channels of channel plate 39 for the purpose of moistening the moisture-retaining layer 5 not shown in the drawing. Possible excess coolant is collected in reservoir 46 . The coolant can be pumped back from reservoir 46 to reservoir 45 or flow back by means of capillary action to reservoir 45 . It is also possible to envisage the excess coolant being poured back manually into reservoir 45 .
This cooler could in this embodiment also be laid on a tabletop. A ceiling plate is once again created if channel plate 39 is rotated through 180° over the longitudinal axis of the channels.
For the drawn embodiment of FIGS. 1 to 6 for applying in for instance vehicles, FIGS. 7 and 8 as ceiling plate and 9 to 12 as cooler in very thin form as both ceiling cooler and for instance tabletop cooler, it is the case that a transparent cooler can be made by making use of for instance glass, PMMA and PC as material for the plates of the chamber which are important for operation and through which air is carried and on which according to 5 a moisture-retaining layer which is transparent, such as for instance a transparent, hygroscopic polymer, is arranged on the relevant sides.
Another means for reducing the surface tension of the coolant, for instance water, could also be used instead of a moisture-retaining layer 5 . It is possible here to envisage a slowly self-sacrificing layer of a soap-like substance, a surface treatment such as a corona treatment or surface roughening.
These alternatives to the moisture-retaining layer can also be wholly transparent, certainly when they are moistened to some extent.
The coolant, for instance water, being visible could moreover have a placebo effect on the people in the user space.
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A device for realizing a cooling effect in a space comprises: a housing with a heat-conducting wall, which housing bounds a chamber through which air can flow; an air inlet which connects to the chamber and to said place, —an air outlet connecting to the chamber; air transport means for transporting air from the air inlet via the chamber to the air outlet; and moistening means for moistening the inner surface of the wall; this such that air supplied by the air transport means is introduced into the chamber via the air inlet, passes along the moistened inner surface of the wall in the chamber and is discharged from the chamber via the air outlet, whereby the water present on the inner surface of the heat-conducting wall evaporates and is entrained by the air flowing by, and the wall is cooled.
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[0001] This application is a continuation-in-part of U.S. Ser. No. 09/442,033 filed Nov. 17, 1999.
FIELD OF THE INVENTION
[0002] The present invention relates to a mounting assembly for use with resiliently mounted blades located opposite to a forming shoe in the forming section of a twin fabric papermaking machine. In such a machine, since the blades are located on each side of the two fabrics, each blade contacts only the machine side of the nearer fabric. This invention is particularly concerned with a flexible mounting which allows the blades mounted thereon to conform locally to Z-direction variations in the path of the forming fabrics across the width of the moving forming fabrics. The flexible mounting allows the blade to move so that the angle of wrap of the forming fabrics as they pass in sliding contact over the fabric contacting surface of the blade is maximized at one of the blade edges and minimized at the other as the blade is displaced further towards the fabrics.
BACKGROUND OF THE INVENTION
[0003] Many structures have been proposed for mounting static forming fabric supporting elements, such as blades, which are used in the forming section of a two, or twin, fabric paper making machine, in which the aqueous stock is injected or conveyed into the space between two opposed forming fabrics. In the forming section, blades in contact with the machine side of each forming fabric are used to improve formation and to assist in the removal of fluid so that an incipient paper web is formed. In certain forming sections of this type, the two forming fabrics moving as a pair are caused to wrap about blades located on both sides of the two forming fabrics and thus follow a somewhat zigzag path through the forming section.
[0004] In twin fabric forming sections equipped with opposed blades, a first set of flexibly mounted blades is located on one side of the fabrics, and a second set of more or less rigidly mounted blades is located on the other side of the fabrics. Suitable machine structures are provided to support both sets of blades, which are collectively referred to as forming shoes. The flexible mountings often utilize arrangements of pressurized hoses or springs to urge the blades into contact with the adjacent one of the two forming fabrics. This invention is concerned with an improved means for flexibly mounting these blades, in which the mounting is flexible in essentially two ways. First, the mounting means of this invention permits the blade to be forced into uniform intimate contact with the machine side of the nearer forming fabric across the width of the forming section. Second, the mounting allows parts of the blade to deflect in the Z-direction locally across the width of the forming fabric in response to localized variations that may occur, and still maintain the blade in intimate contact with the face of the forming fabric.
[0005] In the context of this invention, the following terms have the meanings given:
[0006] “machine direction” means a direction substantially parallel to, or coincident with, the overall direction of travel of the pair of forming fabrics through the forming section;
[0007] “across machine direction” means a direction essentially within the plane of the forming fabrics and perpendicular to the machine direction;
[0008] “Z-direction” means a direction essentially perpendicular to both the machine and cross machine directions, and
[0009] “blade” means any stationary fabric contact element used in the forming section of a twin fabric paper making machine.
[0010] Many arrangements have been proposed in the prior art for resiliently mounting the fabric contacting elements used in a twin fabric forming section. These known mountings locate the blades in the cross machine direction, and provide for movement of the blades in more or less the “Z-direction”. However, in these mountings, Z-direction movement of the blades often involves frictional sliding between fixed and moveable parts of the mounting, which is frequently hampered by clogging of the mechanism by fibers and other matter. Further, in the known prior art arrangements the sliding movement components are generally stiff and inflexible, and thus do not allow for any localized flexing of the blade in the Z-direction in response to localized changes in conditions. Consequently, when localized misalignment of the blade with the forming fabric occurs, areas of poor formation and uneven drainage occur across the incipient paper web.
[0011] Many of the prior art mounting means cause the blade to move towards the fabrics in the Z-direction, and maintain the fabric contacting surface of the blade generally perpendicular to that direction. Further Z-direction movement causes the fabrics to wrap over the blades more or less symmetrically, which increases frictional contact between both the leading and trailing edges of the blade and the machine side of the forming fabric. This contact is known to accelerate the rate of fabric wear. To reduce the rate of fabric abrasive wear due to the wrap angle at the sharp leading edge, the radius of curvature of the blade leading edge is often increased. This has been found to create new problems, because any fluid that was adhering to the machine side surface of the forming fabric will be propelled back into the stock by the rounder edge as the fabrics pass over the fabric contacting surface of the blade. This phenomenon has been found to impair paper formation.
[0012] Kade et al, in U.S. Pat. No. 4,865,692, disclose a support structure for a blade, for use in a conventional single fabric open surface forming section. In this structure, two C-section beams extending across the width of the machine are interlocked to provide an essentially S-shaped structure. The upper C-beam carries the blade, and the lower C-beam is mounted onto the drainage box. The two C-beams are joined together by a flexible spring steel strip, and are urged apart by a clamping element so that the two C-beams engage to form the S-shape. The clamping element is typically an inflatable hose. An adjusting beam is also located between the two C-beams, which also carry stop surfaces. By moving the adjusting beam, different stop surfaces are engaged by pressurizing the clamping means, thus altering the angle of inclination of the fabric contacting surface relative to the machine direction of movement of the fabric. However, this structure only allows a small angular change, the axis about which the angle changes is not defined with any precision, and interlocking of the two C-beams into an S-shaped structure precludes any movement in the Z-direction. Further, although movement of the upper C-beam does not involve any sliding contact, that movement is controlled by the sliding adjusting beam.
BRIEF DESCRIPTION OF THE INVENTION
[0013] The present invention seeks to provide a mounting for a blade in the forming section of a two fabric paper making machine which allows for movement of the complete blade in the Z-direction, localized flexibility of the blade across the width of the forming section in the Z-direction, and some freedom to alter the angle of inclination of the contacting surface in relation to the undeflected path of the forming fabrics. The mounting allows the fabric contacting surface of the blade to be urged into contact with one of the pair of forming fabrics so that it is initially oriented substantially parallel to the contacted surface of the undeflected forming fabric. The blade mounting provides the option of allowing the blade to engage the fabrics so that their angle of wrap about the blade is minimized at the leading edge, and maximized at the trailing edge. This is because the mounting allows the blade to rotate over an arc as it is displaced towards the fabrics. This arrangement reduces the angle of wrap of the forming fabrics about the leading edge of the blade, and permits the use of a relatively sharp doctoring leading edge on the blade. Alternatively, the mounting allows the blade to be engaged with the fabrics so that the wrap angle is maximized at the leading edge, and minimized at the trailing edge. If this arrangement is used, then it is recommended that the radius of curvature of the doctoring leading edge of the blade be increased to reduce fabric wear. The mounting additionally allows the blade to flex locally in the Z-direction, in response to local changes across the width of the forming section, so that the blade conforms more reliably to the line of fabric travel. Since the mounting involves no parts moving in sliding contact, and can also be readily protected from fibers and other solids in the stock, a simple means of controlled movement is provided, whereby more even pressure can be maintained across the width of the forming fabrics, thus reducing defects in the incipient paper web.
[0014] Thus in its broadest embodiment, this invention seeks to provide a flexible mounting for use in the forming section of a twin forming fabric paper making machine consisting essentially of:
[0015] a base member constructed and arranged to be supported by a paper making machine structure;
[0016] a flexible C-shaped beam, having a first beam portion having a first edge and having a second beam portion having a second edge, the first edge of the first beam portion being attached to the base member;
[0017] a fabric contacting blade attachment means, having a leading and a trailing face, attached to the second edge of the C-shaped beam; and
[0018] a pressurized loading tube located within the C-shaped beam between the base member and the second edge of the C-shaped beam.
[0019] Preferably, the first and second beam portions are both arcuate to provide the C-shaped beam. In a first alternative structure, the first beam portion has a second edge, the second beam portion has a first edge, the first and second beam portions are both substantially flat, and the second edge of the first beam portion is attached at an angle at its second edge to the first edge of the second beam portion to provide the C-shaped beam. In a second alternative structure, the first beam portion has a second edge, the second beam portion has a first edge, the first and second beam portions are both substantially flat, the second edge of the first beam portion is attached at an angle at its second edge to the first edge of the second beam portion to provide the C-shaped beam, and the first and second beam portions are a unitary structure.
[0020] Preferably, the base member and the C-shaped beam are fabricated as two separate units and attached together. Alternatively, the base member and the C-shaped beam are fabricated as a single unitary construction.
[0021] Preferably, when a two part construction is used, the first edge of the C-shaped beam is attached to the base member by being lodged into a slot in the base member constructed and arranged to receive the first edge, and the first edge is retained therein by a suitable adhesive. Alternatively, the first edge of the C-shaped beam is mechanically engaged to the base member by means of a slot in the base member constructed and arranged to receive the first edge, or by means of a direct mechanical attachment means.
[0022] Preferably, the mounting further includes a flexible sealing means located between the second edge of the C-shaped member and the base member. More preferably, the sealing means comprises a flexible strip of suitable width. Preferably, the edges of the sealing strip are engaged in cooperating slots in the second edge of the C-shaped beam and the base member.
[0023] Preferably, the pressurized loading tube is located in a slot constructed and arranged in the base member to receive it. More preferably, the pressure tube further includes a pressure rib adjacent the second edge of the C-shaped beam.
[0024] Preferably, the fabric contacting blade attachment means attached to the second edge of the C-shaped beam further includes a leading face and a trailing face, together with liquid venting means connecting the leading face to the trailing face. More preferably, the liquid venting means comprises a series of holes or slots from the leading face to the trailing face through the fabric contacting blade attachment means, the holes or slots being spaced apart in the cross-machine direction.
DESCRIPTION OF THE DRAWINGS
[0025] [0025]FIG. 1 shows a cross sectional diagram of one embodiment of the flexible mounting according to the invention on a forming shoe for a two fabric forming section, with the blade retracted;
[0026] [0026]FIG. 2 shows the embodiment of FIG. 1 with the blade moved into sliding contact with the forming fabrics,
[0027] [0027]FIG. 3 shows the embodiment of FIG. 1 with the blade pressed into engagement sufficiently to deflect the forming fabrics;
[0028] [0028]FIGS. 4, 5, 6 , 7 and 8 show alternative constructions of the mounting; and
[0029] [0029]FIG. 9 shows a cross section on the line I-I of FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] In the following description it is assumed for simplicity that the two forming fabrics run in a substantially horizontal direction. For machines with non-horizontal forming fabrics it is to be understood that terms such as “up” and “top” refer to a direction or location toward the fabrics, and are thus essentially in the Z-direction.
[0031] Referring first to FIG. 1, the base member 1 supporting the flexible mounting is attached to a suitable support structure, for example by the conventional T-bar arrangement 2 . Other mounting means are known and used. The flexible mounting comprises a beam 3 having a C-shaped cross section extending across the width of the forming section. The C-shaped beam 3 is ideally one single piece, unless its length precludes manufacture as one piece. If a multiple piece beam is used, the ends should be butted closely together. At its first edge 4 the C-shaped beam 3 is lodged into the slot 5 in the base member 1 , and held in place by a suitable adhesive, casting or potting compound 6 . The adhesive 6 is chosen to provide adequate engagement of the edge 4 into the slot 5 , and to have an acceptable service life under the operating conditions of the forming section, which will place significant stresses on the adhesive. The cured adhesive either can be essentially rigid, or can provide a modicum of flexibility for the edge 4 in the slot 5 . To ensure adequate engagement between the adhesive 6 and the first edge 4 of the C-shaped beam, ribs 7 can be provided, and the slot can have the dovetail shape shown.
[0032] It is thus apparent that although the C-shaped beam is securely held in the slot 5 by the adhesive 6 , it can have some freedom to rotate relative to the mounting beam 1 , by flexure of the compound 6 .
[0033] At its second edge the C-shaped beam has a relatively thick rib 8 , which includes two slots 9 , 10 . An approximately square cross section is suitable for the rib 8 . The lower slot 9 engages the upper edge of a flexible sealing strip 11 which is conveniently an elastomer extrusion, and which extends across the width of the forming section. It is also desirable that the sealing strip is one piece; if more than one piece is used the ends should be closely butted together, and preferably cemented, to provide a water tight seal. The lower edge of the sealing strip 11 is engaged into a suitable slot 12 in the base beam 1 . The upper slot 10 carries the fabric engaging blade 13 . A pressurized loading tube 14 is located between the base beam 1 and the rib portion 8 of the C-shaped beam 3 . The tube is conveniently retained in place by a suitable recess 15 in the base beam 1 . The loading tube also conveniently includes a pressure rib 16 on its top surface.
[0034] Referring now to FIGS. 2 and 3, as the loading tube 14 is pressurized (for example with air or with a liquid under pressure) it expands, and engages the underside of the rib portion 8 of the second edge of the C-shaped beam 3 . As the pressure is increased, the tube 14 expands and moves the blade 13 into sliding engagement with the nearer one of the forming fabrics 17 (see FIG. 2). Two fixed blades 18 , 19 will generally be located on the other side of the forming fabrics in the forming shoe. In FIGS. 2 and 3 the forming fabrics move in the direction of the arrow A. As the loading tube continues to expand, blade 13 is moved further into engagement with the forming fabrics 17 as at 20 (see FIG. 3), and the two fabrics 17 are deflected somewhat in the Z-direction, as shown by the arrow B. At the same time, the flexible seal 11 is also extended. The C-shaped beam 3 has sufficient flexibility to bend in the area 21 to allow the blade 13 to contact the forming fabrics 17 and deflect them, and also to allow the rib portion 8 of the C-shaped beam 3 to rotate over an arc as indicated by the arrow C, so that, as shown in FIG. 2, the upper face 22 of the blade 13 is initially located to be substantially parallel to the run of the forming fabrics 17 . Further expansion of the loading tube 14 , as shown in FIG. 3, in addition to moving the blade 13 in the Z-direction, causes the rib portion 8 , and the face of the blade 13 to move so that the leading edge 24 of the blade 13 is displaced a small distance towards the fabrics 17 , and the trailing edge 23 is displaced a relatively greater distance toward the fabrics. This maximizes the wrap angle of the forming fabrics 17 at the trailing edge 23 of the blade 13 , and minimizes the wrap angle at the leading edge 24 of the blade 13 . This assists in reducing fabric wear caused by friction at the leading blade edge 24 . When the loading tube 14 is depressurized, the C-shaped beam 3 retracts and moves the blade 13 to the position shown in FIG. 1, so that the blade 13 is not in contact with the forming fabrics 17 . Alternatively, the blade can be mounted so that the angle of wrap is maximized at the blade leading edge, and minimized at the blade trailing edge. If this is done, then it is recommended that the radius of curvature of the blade leading edge be increased so as to minimize fabric wear.
[0035] Alternative arrangements for attaching the C-shaped beam 3 to the base member 1 are shown in FIGS. 4, 5 and 6 .
[0036] In the construction shown in FIG. 4, the ribbed first edge 25 of the C-shaped beam 3 is secured in place in the tapered slot 29 . A locking bolt 27 seated in a threaded hole 28 serves to clamp the edge 25 between strips 30 A and 30 B. In this construction, the slot 29 can be made narrower, and either or both of the strips 30 A and 30 B can be omitted.
[0037] In the construction shown in FIG. 5, the ribbed first edge 25 of the C-shaped beam 3 is attached directly by bolts 31 in threaded holes 32 in the base member 1 .
[0038] In the construction shown in FIG. 6, the C-shaped beam 3 and the base member 1 are fabricated as a single unitary construction.
[0039] Other forms of suitable mechanical engagement means are also well known and can be used.
[0040] The constructions shown in FIGS. 1 - 6 in practice have also been found in certain circumstances to have a disadvantage. If the quantity of liquid being doctored off by the blade 13 is relatively high, splash-back can occur. This has the effect of at least some of the doctored off liquid being projected laterally and upwardly toward the machine side of the adjacent forming fabric as it moves toward the blade 13 . This can result in at least some of the splashed back liquid re-entering the adjacent oncoming forming fabric, with a deleterious effect on the formation process going on between the two opposed forming fabrics. The construction shown in FIGS. 7 and 8, together with the cross section shown in FIG. 9, overcomes this difficulty. As shown in both FIGS. 1, 2, 3 , 4 , 5 and 6 , the forming fabrics 17 move in the direction of the arrow A. It is also contemplated that by reversing the positions of the trailing and leading edges 23 , 24 of the blade 13 , the mounting can be used with forming fabrics traveling in the direction of the arrow D in FIG. 3.
[0041] A further alternative structure for the C-shaped beam is shown in FIGS. 7 and 8. In this construction, the C-shaped beam 3 consists essentially of a first beam portion 31 and a second beam portion 32 . These two portions are each essentially flat. The first edge 33 of the first portion 31 includes a rib 7 which is secured into the slot 5 in the base member 1 . The second edge of the first beam portion 31 and the first edge of the second beam portion 32 are attached together along the line 34 , at a suitable angle E. This angle is chosen to suit the desired overall height (in the Z-direction) of the mounting. In this construction it is preferred that the two beam portions 31 and 32 of the C-shaped beam are fabricated as a unitary structure. The fabric contacting blade attachment means 8 is attached to the second edge 35 of the second beam portion 32 . As shown, a cooperating rib 36 and slot 37 is used to attach the attachment means 8 to the C-shaped beam 3 . The remainder of the construction is essentially the same as that shown in FIGS. 1 - 5 .
[0042] In this construction, the attachment means 8 is not solid as in the other Figures, but instead is provided with a venting means, through which at least a proportion of any liquid accumulating on the leading face 84 of the attachment means 8 can be vented at its trailing face 85 . By this expedient, enough of the liquid doctored off by the blade 13 can be transferred to the trailing face of the attachment means 13 to eliminate substantially the risk of splash-back. FIG. 9 shows in cross section a part of the attachment means 8 including a suitable venting means. A series of slots 81 with tapered spacers 82 between them are provided in the attachment means 8 , between the leading face 83 and the trailing face 84 . The slots are spaced apart along the attachment means 8 in the cross machine direction. In order to avoid obstruction of the slots by solid from the stock, it is preferred that the spacers 82 should have an angled leading edge as shown at 85 ; a flat space as at 86 between the slots 81 is not desirable. At least a portion of the doctored off liquid then follows the path indicated schematically by the arrows G, and is drained away from the space downstream of the blade mounting. A further variation on this construction is also shown in FIG. 8. On the trailing face 83 of the attachment means 8 a deflector rib 87 is provided, which serves to deflect the liquid vented through the slots 81 away from the machine side of the adjacent forming fabrics 17 . The arrangement shown in FIG. 3, with the forming fabric moving in the direction of the arrow D, may also serve to alleviate splash-back problems.
[0043] It should be noted that in fabricating an attachment means 8 including slots 81 and spacers 82 care should be taken to ensure that the resulting structure is sufficiently strong to support the element 13 properly. It should also be noted that, unlike the construction shown in FIGS. 1 - 5 , it is recommended that the form of construction shown in FIGS. 7 and 8 should not be reversed, and should only be used with the forming fabrics moving in the direction shown at F.
[0044] The mounting including the arcuate or angled flexible C-shaped beam structure 3 also provides a yielding, somewhat pliant support for the blade 13 in the Z-direction across the width of the forming section, which allows the mounting to flex in response to localized variations in the path of the forming fabrics. Variations in the location of the fabric surface across the width of the machine, essentially in the Z-direction relative to the blade surface, may be caused by various factors, such as uneven stock flows, temperature variations, localized variations in the wear surfaces of the blades themselves, or misalignment of the mounting structures supporting blades. This level of flexibility in the mounting also allows the blade 13 to conform to such localized variations, while applying a constant and even pressure to maintain thus retaining the face 22 of the blade in intimate contact with the machine side of one of the moving forming fabrics.
[0045] The loading of the tube 14 may be accomplished either pneumatically or hydraulically. Hydraulic pressure is preferred, since it provides a higher degree of control than gasses and provides viscous dampening of any blade vibration.
[0046] In this mounting, there are no moving components which are susceptible to sliding friction to move the blade, and the presence of the elastomer sealing strip 11 eliminates areas where fibers and solids can accumulate. It is therefore not recommended that the sealing strip be omitted, although the mounting will function without it.
[0047] By means of this invention, it is now possible if desired to employ blades whose leading edges have a much smaller radius of curvature than those utilized in “conventional” mounting assembly designs so as to reduce the occurrence of re-entrant water. Water re-entry is the result of the water layer that clings to the machine side surface of the fabric that is not doctored off by the leading edge of the blade 13 . This water becomes driven back into the sheet disrupting sheet formation. In the mounting assembly of the present invention, the entire fabric contacting surface of the blade can be maintained in contact with the fabric so that it is in intimate contact with the machine side of the fabric. Consequently, the leading edge can be as sharp as is practical so as to skim off any fluid clinging to the machine side of the fabric. As the blade 13 is pressed in the Z-direction further into the fabrics 17 , the mounting allows the blade 13 to move so that the wrap angle of the fabrics at the leading edge 24 of the blade 13 is minimized, and the wrap angle at the trailing edge 23 of the blade 13 is maximized.
[0048] The C-shaped beam 3 can be fabricated from a variety of materials, including both metals, such as spring steels, stainless steels, and fibre reinforced plastics such as so-called “fibreglass”, which is the presently preferred material. Similar materials can also be used when the C-shaped beam and the base member 1 are fabricated as a single unit. Since the conditions of use vary significantly between paper making machines, some experimentation is required to obtain the desired level of flexibility in the C-shaped beam 3 . If an adhesive is used to retain the C-shaped beam in the base member 1 , such as an elastomer based adhesive, a casting compound, or a potting compound, after curing it should be relatively stiff, thus providing a mounting somewhat similar in properties to the well known rubber-in-shear bushes. Under certain circumstances, it may be required to use a more rigid means of engaging the C-shaped beam, such as the mechanical engagement arrangements discussed above or a unitary construction of the C-shaped beam and the base member combined. Alternatively, when an adhesive is used the engagement can be stiffened by choosing the fit between the edge 4 of the C-shaped beam 3 and the slot 5 so that the amount of adhesive can be minimized. Additionally, when a C-shaped beam with two substantially flat beam portions is used, the construction can be arranged so that the first beam portion is essentially rigid, and serves primarily to support a flexible second beam portion. It is thus clear that for any specific set of operating conditions some experimentation will likely be required to obtain the desired degree of flexibility.
[0049] Similarly, the base member 1 and the attachment means 8 can each be fabricated from a variety of materials, including both metals, reinforced plastics, and engineering plastics. The preferred material is fiber reinforced plastic, such as so-called “fibreglass”. Although the base member 1 is shown as having a substantially rectangular cross-section, other cross-sectional shapes, both tubular and solid, can be used.
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A flexible mounting for use in the forming section of a twin forming fabric paper making machine consisting essentially of a base member supported by the paper making machine structure to which is attached a flexible C-shaped beam. The C-shaped beam has one edge attached to the base member, and a fabric contacting blade attachment means at the other edge. A pressurized loading tube is located within the C-shaped beam between the base member and the second edge of the C-shaped beam. When the pressurized loading tube is loaded, the C-shaped beam flexes thus allowing the blade to move initially into contact with a forming fabric. As the pressurized tube is further loaded, the contact face of the blade is moved into further engagement with the forming fabric. In a preferred construction, the wrap angle of the fabrics at or about the blade leading edge can be minimized. The mounting thus can diminish wear of the fabric as it passes over the blade. The mounting also allows localized flexing in the blade to accommodate localized variations in conditions, such as variations in stock thickness. The mounting can also include vents whereby liquid accumulated upstream of the blade is vented downstream of the mounting.
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TECHNICAL FIELD
The present invention relates to test devices, and in particular to cable network test devices having interactive features for assisting a user in selecting tests to be run to solve a problem in the cable network.
BACKGROUND OF THE INVENTION
Test equipment, and in particular cable network test equipment, frequently requires a user to choose between functionally distinct tests. The tests are selected in dependence upon a problem being investigated. Typically, the tests are selected from a list-type menu structure, an icon-based menu structure, or a combination of the two menu structures. The user must be able to know which tests and test modes to employ in each particular case. Multiple tests are often required to investigate most problems, such as a poor quality of digital reception, for example. To assist the user, shortcuts can be provided in a graphical user interface of the test equipment. The shortcuts take the user directly from one mode to another without having to return to the main menu.
Referring to FIG. 1 , a flow chart of a prior-art method of investigating a network problem is shown. At a step 101 , a user, such as a field test technician, selects a test to be run. The test is selected based on the technician's knowledge of which tests need to be run to investigate a particular problem, as shown schematically with an arrow 102 . At a step 103 , the tests are run by the test device. At a step 104 , the test results are obtained, typically in form of a table or a graph on a display unit of the test device. At a step 105 , the results are analyzed by the technician to find a root cause of the problem. This step also requires a specific knowledge by the technician, as is shown by an arrow 106 . At a step 107 , the technician selects further action or actions to be taken to further investigate the problem, and the process continues as illustrated with dots 109 until the root cause of the problem is found. The step 107 of selecting further actions to be taken also requires knowledge 108 by the technician of all tests available to the test device and the appropriate circumstances under which the tests are to be run.
One drawback with the traditional approach illustrated in FIG. 1 is that it requires the field service technicians using the test equipment to know in detail the circumstances under which each test is to be run. Considering a large number of tests that can be run to troubleshoot a particular problem, and considering a significant extent of problems that might occur, this requirement is difficult to meet in practice. Furthermore, new equipment is being developed and added to a typical cable network to expand services delivered to clients. New equipment and associated new services can only be deployed if an equipment update is adequately supported by a growing testing and troubleshooting capability, which requires new tests to be added on ongoing basis. Maintaining an adequate up-to-date training of the technical personnel in such rapidly growing environment represents a formidable challenge.
One known solution to simplify the testing procedure is to program the test equipment to run predetermined successions of tests using a scripted succession of test commands. In this mode, which is sometimes called “autotest” mode, the testing equipment consecutively runs all the measurements listed in the script, typically on multiple information channels. At the end of the measurements cycle, the test equipment generates a table showing test results. For example, channel power readings can be displayed, for all channels present, so that the user can check whether channels of interest have sufficient power to be reliably detected. Many other tests, such as modulation error ratio (MER), bit error ratio (BER), carrier-to-noise ratio (CNR), quadrature amplitude modulation (QAM) ingress, etc., are also performed on channel-by-channel basis.
While scripted “autotest” measurements provide an advantage of standardized testing done by field service technicians, allowing comprehensive and standardized data logging, the sheer amount of information presented to the technician at the end of the “autotest” represents a difficulty to the technician, whose task is to quickly determine the root cause of the problem. To be able to understand and navigate in vast amounts of data generated by the “autotest”, the technician must not only understand the basics of network operation, but also be familiar with data processing and have strong analytical skills. Therefore, introduction of “autotest” does not reduce the amount of training required. In essence, it simply expands the required training into another area.
The prior art is lacking a solution that would allow a user to quickly analyze a particular problem without requiring ongoing, extensive, and time-consuming on-the-job training. Accordingly, it is a goal of the present invention to provide a solution that reduces the amount of training required, while streamlining and standardizing the testing process.
SUMMARY OF THE INVENTION
A test device of the invention is constructed and programmed to guide the user in finding the root cause of the problem. The guidance is achieved by providing a novel graphical interface for the user.
In accordance with the invention there is provided a test device for testing a cable network, comprising:
an input port, for connecting to the cable network;
a testing apparatus coupled to the input port, for performing tests of the cable network;
a display;
a central processing unit (CPU) for controlling the testing apparatus and the display; and
a graphical user interface (GUI) for inputting user commands to the CPU and for conveying results of the tests by displaying them on the display;
wherein the GUI comprises a set of icons including first and second icons,
wherein the first icon is for representing a network problem category, wherein the first icon has a graphical feature corresponding to the network problem category, wherein the CPU is suitably programmed to cause the testing apparatus to perform a first test of the cable network automatically or upon selecting the first icon by a user of the test device;
wherein the second icon is for representing a second test of the cable network, wherein the second icon has a graphical feature corresponding to the second test, wherein the CPU is suitably programmed to cause the testing apparatus to perform the second test of the cable network upon selecting the second icon by the user;
wherein the second icon has a guiding feature indicative of a current status of the first test, for guiding the user whether to select the second icon to cause the test device to perform the second test, in dependence upon the current status of the first test.
The current status of the first test can represent a result of the first test. Depending on the result, the test device highlights an icon representing a next recommended step. In this way, the graphical features representative of the current status of tests currently in progress can function as a guide for the user in selecting a further test for the test device to perform. When the next test is selected and executed, its result will determine which icons are to be highlighted or brought up on the next display screen, and so on.
In accordance with yet another aspect of the invention, the graphical interface further includes “problem category icons” for selecting a particular problem category by the user of the test device. When the user selects a particular problem category, at least one of the test actions are run automatically in the background; further guidance to the user is provided in graphical form, depending on the results of these automatically run tests.
In accordance with the invention there is further provided a method of finding a root cause of a problem in a cable network, comprising:
(a) providing a test device having an input port, a testing apparatus coupled to the input port, a display, a central processing unit (CPU), and a graphical user interface (GUI) for inputting user commands and for conveying results of the tests by displaying them on the display;
(b) connecting the input port of the test device to the cable network;
(c) automatically selecting, via the CPU, a first test to be run by the testing apparatus;
(d) performing the first test selected in step (c) to obtain a result of the first test; and
(e) using the GUI to display the result of the first test, obtained in step (d), in the form of a graphical feature of an icon representing a next action to be taken to find the root cause of the problem,
(f) whereby the user of the test apparatus is guided to take the next action by selecting the icon representing the next action.
The next action can include selecting a test mode for the next test to be run, displaying detailed results of the first test, or running additional tests. The first test can be user-selected using an icon corresponding to a general problem category, for example a problem category defined in a so called “trouble ticket”.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments will now be described in conjunction with the drawings in which:
FIG. 1 is a flow chart of a prior-art testing method of finding a root cause of a network problem;
FIG. 2 is a flow chart of a method of testing according to the present invention;
FIG. 3 is a frontal schematic view of a test device of the present invention;
FIG. 4 is an example graphical interface of the invention showing results of channel power measurements;
FIG. 5 is an example graphical interface of the invention showing selectable icons indicative of previous test results;
FIGS. 6 and 7 are example graphical interfaces of the invention showing icons guiding the user to a next recommended test; and
FIG. 8 is a flow chart showing a recommended order of tests for troubleshooting a digital channel reception problem.
DETAILED DESCRIPTION OF THE INVENTION
While the present teachings are described in conjunction with various embodiments and examples, it is not intended that the present teachings be limited to such embodiments. On the contrary, the present teachings encompass various alternatives, modifications and equivalents, as will be appreciated by those of skill in the art.
Referring to FIG. 2 , a flow chart of a test method 200 according to the invention is shown. At a step 201 , a user of the testing device selects a problem category of a problem to be solved, for example “unstable digital reception” or “no signal on channel N”, or the like. This step requires user input shown at 202 . The user selects the problem category according to a problem description by the customer. The problem description is usually specified in a “trouble ticket”. Upon receiving the user input 202 , at a step 203 , the test device automatically determines which tests must be run to increase the likelihood of solving a problem of the problem category selected at the step 201 .
The step 201 of selecting the problem category by the user is optional. The test device can be programmed to automatically determine which tests to run upon connecting to the network being tested. In this case, the user input 202 would not be required, and the step 203 of determining which tests to run can be completely automatic.
At a step 204 , the test device runs the tests automatically, preferably in the background, allowing the user to continue working with the test device. At a step 205 , the test device analyzes the test results, characterizing each category of test results as nominal or anomalous. The test device can indicate the anomalous categories of test results by highlighting their corresponding icon or icons on the display of the test device. Thus, the bulk of data representing the first test results is normally hidden from the user, although the data remains accessible by the user by selecting an appropriate icon, if so desired. The test device then determines which tests must be run next to find the root cause of the problem, or to increase the likelihood of finding the root cause. The test device recommends further actions to be taken, for example further tests to be run, by highlighting corresponding icon or icons on the display of the test device. The user is not required to analyze the data and draw conclusions, because at the step 205 , the further actions are determined automatically by the test device and are recommended for the user to take, by highlighting corresponding icons, the selection of which will result in the test device taking these actions. At a step 206 , the user selects at least one of highlighted icons. The step 206 requires a user input 207 . The process continues at 208 , wherein after taking the actions selected at 206 , the user is guided to take further actions depending on the result of the actions taken at 206 , and so on, until the root cause of the problem is found.
The test method 200 considerably simplifies requirements for training of field service technicians, while streamlining and standardizing the testing procedure. The CPU of the test device must be suitably programmed to be able to determine which test(s) to run at the step 203 and which actions to take next at the step 205 . Many test devices can use the same program for performing the steps 203 and 205 . As a result, the test procedure is standardized, without requiring re-training of all technicians whenever a new test is introduced.
The icons representing a next step to be taken can be highlighted using any suitable graphical feature, for example bold lines, green or red color of the icons, and the like. Some graphical features of the icons can represent whether the icon and a corresponding action is presently available to the user. Furthermore, the icons representing the tests that are too early to take because the results of previous tests are not yet available, can remain entirely hidden, appearing only when it is appropriate to take corresponding actions. Alternatively or in addition, the icons representing further tests can be disposed in a recommended order of execution of these further tests.
Referring now to FIG. 3 , a test device 300 according to the present invention is shown. The test device 300 is preferably a handheld device. The test device 300 has an input port 301 , for connecting to equipment to be tested, such as a cable network; a testing apparatus 302 coupled to the input port 301 , for performing tests of the cable network; a display 303 ; and a central processing unit (CPU) 304 for controlling the testing apparatus 302 and the display 303 . The test device 300 also has a graphical user interface (GUI) between the test device 300 and the user of the test device 300 , for inputting user commands and for conveying results of the tests by displaying them on the display 303 , for example in form of a graph 314 . The GUI has a set of icons 305 - 311 for representing actions to be taken by the test device 300 upon selecting the icons 305 - 311 by the user. Of the icons 305 - 311 , some icons have graphical features indicative of a status of tests associated with some other icons. For example, the icon 309 has graphical features indicative of a status of a test associated with the icon 308 . When the test run by selecting the icon 308 has a result that indicates that an action represented by the icon 309 must be taken next to find root cause of the problem, the icon 309 is highlighted, so the user is guided to take the next action by selecting the icon 309 , in accordance with the method 200 described above.
The status of the test associated with the icon 308 can be representative of whether the test has been completed by the test device 300 . The status of the test can represent a result of that test, for example whether the test has failed, so that, for example, if the test associated with the icon 308 has failed, the next icon 309 is highlighted. Some of the graphical features of the icons 305 - 311 can represent the status of the tests represented by the same icons. For example, while the test is running, a corresponding icon can be grayed out indicating that it cannot be selected again until the test is completed. When the test is completed, the corresponding icon appearance can have a bearing on a result of the test, for example whether the test has passed or failed. For example, if the test represented by the icon 308 has failed, an exclamation sign may be placed on that icon, as shown in FIG. 3 .
Some of the icons 305 - 311 , for example the icons 305 - 307 , have graphical features that are indicative of a problem category of a problem with the cable network. The user would normally select one of the icons 305 - 307 that represents a problem outlined in the trouble ticket, thus performing the step 201 of the method 200 discussed above. A test corresponding to the problem category selected by the user is run automatically, preferably in the background, upon selecting one of the icons 305 - 307 . The CPU 304 is suitably programmed to select the test or tests to be run depending upon the likelihood of solving the problem of the problem category highlighted by the user. In general, wherein a first icon represents a first action to be taken and a second icon represents a second action, the graphical features of the second icon function as a guide for the user to assist the user in deciding whether to select the second icon to cause the test device to take the second action, for example to run a second test, or to display a detailed table of results of previous test highlighting problem areas. When the second test has been completed, its results will have a bearing on which icon is to be selected next, to run a third test, and so on; in this way, the user is guided to finding a root cause of the network problem.
A subset of the icons 305 - 311 , for example the third-row icons 309 and 310 , can represent tests to be performed in one of a plurality of test modes of the testing apparatus 300 . At least one graphical feature of the third-row icons 309 and 310 functions as a guide for the user in selecting a particular test mode to be used for a next test to be performed by the testing apparatus 300 . Alternatively or in addition, the third-row icons 309 and 310 can represent high-priority and low-priority actions, respectively, so that an icon corresponding to the low-priority action, for example the icon 310 , is not selectable until the high-priority action is completed. The priority status of the third-row icons 309 and 310 can be managed from the head end of the cable network and is communicated to the test device through the cable network, or the CPU 304 can be suitably programmed to prioritize the third-row icons 309 and 310 . The icons are prioritized by a graphical feature thereof and/or by a relative position of the icons on the display 303 of the test device 300 . In one embodiment of the invention, the icons are prioritized in dependence upon a result of the action taken upon selecting the icon 308 by the user, as is symbolically indicated with an arrow 315 .
Some of the icons, for example the fourth-row icons 311 , can be disposed along an edge of the display 303 and are selectable by corresponding “soft keys” 312 disposed on the test device 300 proximate to the edge of the display 303 . Alternatively, the icons 305 - 311 can be selectable by using Left-Up-Right-Down buttons 313 of the test device 300 .
The test device 300 can have an optional storage device, not shown, so that the test results can be stored on the storage device for subsequent analysis. Alternatively or in addition, the test results can be communicated to another test device or to a central office or the head end of the cable network being tested.
Turning now to FIG. 4 , an example screen 400 of the GUI of the invention is presented. The screen 400 shows results of channel power measurements on multiple channels. To measure signal power of multiple channels, the CPU 304 causes the test apparatus 302 to tune to these channels one by one and to measure the power of the signal, channel by channel, storing the individual channel power readings in memory. The screen 400 shows results of channel power measurements 401 for multiple channels, indicating pass-fail status of individual channels at 402 . The screen 400 also shows results of modulation error ratio (MER) of individual channels at 403 , as well as average and minimal digital quality index (DQI) of individual channels at 404 and 405 , respectively.
Icons 406 - 411 are of a particular interest. Selecting the icon 406 causes the main menu to be displayed; selecting the button 407 causes a MPEG stream analysis results to be displayed and further MPEG tests to be performed; selecting the button 408 causes channel DQI measurement detailed results to be displayed and further DQI measurements to be performed; selecting the button 409 causes the channel power measurement detailed results to be displayed and further DQI measurements to be performed; selecting the button 410 causes the constellation measurements detailed results to be displayed and further constellation measurements to be performed; and selecting the button 411 causes detailed QAM ingress results to be displayed and further QAM ingress measurements to be performed. The icon 410 is highlighted, while icons 407 to 409 and 411 remain dark and disabled because, based on the result of previous measurements, the constellation measurement is the next step that must be taken to troubleshoot the problem at hand. The icons 406 - 411 can be grayscale or color coded.
Referring now to FIG. 5 , another example screen 500 of the GUI of the invention is shown. The screen 500 shows results of channel power level/MER/bit error ratio (BER) at 501 , RF spectrum at 502 , and DQI at 503 . The screen 500 is displayed when the constellation measurement recommended on the screen 400 has been already performed and yielded a “failed” result, along with a spectrum flatness measurement that has yielded a “passed” result. Of particular interest are icons 504 to 510 showing the measurements performed or available to be performed. The icons 504 and 509 indicate the failed constellation measurement result and the passed spectrum flatness test result, respectively. The icons 510 can be made selectable by the soft keys 312 of FIG. 3 , for example.
Turning to FIG. 6 , another example screen 600 of the GUI of the invention is shown. The screen 600 shows a result of channel-by-channel testing initiated by selecting an icon from a menu list or by other means. On the screen 600 , the results of testing a digital channel # 087 are presented. The test has yielded a “fail” result, as indicated at 601 . The current measurement (channel signal power) is indicated by a border 602 drawn around an icon 603 representing the channel power measurement. In this example, the test device 300 also recommends MER and BER of this channel to be measured next, as indicated by a highlighted icon 604 representing MER and BER tests and by the rest of the icons remaining “grayed out”.
Turning to FIG. 7 , another example screen 700 of the GUI of the invention is shown. Guided by a previous menu or icon, the test technician has selected a particular digital channel to test. The digital channel tests can include, for example, a MER test and a BER test. Upon completion of the MER and BER tests, the screen 700 appears on the display 303 of the test device 300 . The MER and BER test results are displayed on the screen 700 at 701 and 702 , respectively. Additional icons representing Level, Constellation, Tilt, DQI, QAM Ingress, and Channel plan are available for user selection and will be highlighted if background tests suggest they are anomalous. In this way, the technician is guided by the GUI of the test device 300 to run a succession of tests in dependence on intermediate results of the tests that have already been run, with the purpose of finding the root cause of the problem.
Turning now to FIG. 8 , a flow chart is presented showing typical measurements required for troubleshooting a digital channel reception problem in a cable network. The “digital channel reception” is one of many problem categories selectable by the user as described above by highlighting a corresponding icon. The troubleshooting process starts at 801 . At a step 802 , the total integrated power at a test location of the cable network is checked. At a step 803 , spectrum tilt or roll-off is measured. At a step 804 , the spectrum flatness is evaluated. At a step 805 , the power level of the channel of interest is measured. At a step 806 , the channel MER or carrier-to-noise ratio (CNR) is evaluated. At a step 807 , signal power levels of adjacent channels are evaluated. At a step 808 , the channel DQI is determined. At a step 809 , the channel quadrature amplitude modulation (QAM) ingress noise is measured. At a step 810 , the channel spectrum is measured. At a step 811 , the channel QAM constellation is checked. At a step 812 , the channel MPEG stream is checked. The process ends at 813 . For the steps 802 to 812 , the availability of test results, indication of results which are anomalous, and the next step to be taken are suggested to the test technician by highlighting corresponding icons, as described above, and by hiding or “graying out” the icons representing measurement steps that are nominal or that are too early to take. For example, until the channel power is evaluated at 805 , it is too early to evaluate the MPEG stream at the step 812 . Thus, the flow chart of FIG. 8 can be used as an example guide in programming the CPU 304 to perform corresponding tests and highlight corresponding icons for a next test to perform. The particulars of CPU programming depend on kind and topology of the cable network to be tested.
All the tests 802 to 812 can be run automatically in the background, in the order shown; as the test results become available, the icons of the GUI corresponding to the tests 802 to 812 become activated, so that the test results can be displayed. For example, these icons can be colored red or green, in dependence on the result of the corresponding test, or they can simply be redrawn from a gray color to some other color.
Many color arrangements are of course possible. The color coding of icons or other graphical features introduced into the icons are intended to indicate that the icon is available for selecting upon completion of the corresponding test, so that displaying the test results is now possible. Furthermore, these graphical features, when combined in a single icon, can represent various test information so far obtained.
Referring back to FIGS. 2 and 3 , one general method of testing a cable network according to the present invention consists of the following steps:
(a) providing a test device, such as the test device 300 having the input port 301 ; the testing apparatus 302 coupled to the input port 301 ; the display 303 ; the central processing unit (CPU) 304 ; and the graphical user interface (GUI) for inputting user commands and for conveying the results of the tests, for example the graph 314 , by displaying them on the display 303 ;
(b) connecting the input port 301 of the test device 300 to the cable network;
(c) using the GUI to allow a user of the test device 300 to select a problem category of the problem represented, for example, by the trouble ticket issued in response to a complaint by the customer of the cable network. As noted above, this step can in principle be omitted, in which case the CPU 304 would have to be programmed to run the same set of initial tests automatically. This step is exemplified by the step 201 of the method 200 of FIG. 2 ;
(d) automatically selecting, via the CPU 304 , a first test to be run by a testing apparatus, depending upon the likelihood of solving a problem of the problem category selected by the user in step (c). This step is exemplified by the step 203 of the method 200 ;
(e) performing the first test selected in step (d) to obtain a result of the first test. This step is exemplified by the step 204 of the method 200 ; and
(f) using the GUI to display the result of the first test, obtained in step (e), in form of a graphical feature of a summary icon representing whether the corresponding test results are anomalous or highlighting an icon representing a next action to be taken to find the root cause of the problem. This step is exemplified by the step 205 of the method 200 .
By performing steps (b) to (f), the user of the test apparatus 300 is guided to view in detail the most anomalous test results and/or to take a next action by selecting the next icon, which becomes highlighted or activated. The next action can include selecting a test mode for a next test to be performed by the test device; for example, the user selects one of the highlighted icons at the step 206 of the method 200 . The next action can also include displaying the data obtained in the graphical form, zooming on a particular area of the graph, performing statistical analysis, and so on.
Preferably, after step (e), a step (e1) is performed to cause the CPU 304 to automatically prioritize a plurality of further actions to be taken to find the root cause of the problem, in dependence upon the result of the first test obtained in step (e). Preferably, the GUI is used to display the result of the first test in form of a graphical feature of a plurality of icons representing the plurality of further actions, for example a color of the icon. The graphical feature is indicative of a high-priority action and a low-priority action of the plurality of further actions to be taken. Further, preferably, an icon representing the low-priority action will not be selectable until the high-priority action has been completed.
The test results can be stored on an optional storage device of the test device 300 or communicated to another test device or to a head end of the cable network. The centralized storage of the test results is particularly advantageous because it allows detailed analysis of the data collected by multiple test devices 300 at multiple locations of the cable network.
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A test device is disclosed having a display and a graphical user interface (GUI) that provides guidance to a user by displaying first and second icons for representing first and second actions to be taken by the test device upon selecting the first and the second icons, respectively, by the user. To provide the guidance to the user, the second icon has graphical features indicative of the current status of the first action. For cases where the first action is a test that failed, the second action is highlighted thereby guiding the user to take the second action in response to the failed test. At least one of the graphical features of the second icon is indicative of whether the second icon is currently selectable by the user.
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This is a continuation of application Ser. No. 268,834 filed July 3, 1972 which is, in turn, a continuation of application Ser. No. 105,013 filed Jan. 8, 1971 both abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for controlling pollution and, in particular, to a novel method and apparatus which eliminates pollutants from a fluid through chemical effects created by a corona discharge.
More specifically, the invention relates to a pollution control method and apparatus adapted to remove pollutants from a fluid such as created in the exhaust gas of an internal combustion engine and the like whereby the polluted material is mixed with an oxygen containing fluid and is directed through a novel pollution elimination chamber. The pollution elimination chamber includes a corona-emitting member having a plurality of elements which produce an intense corona field to reduce pollution therein. In one embodiment of the invention, the corona-emitting member includes a plurality of discs having an outer peripheral surface which significantly intensifies the production of corona within the pollution-elimination chamber.
As is well known, the existence of a multitude of exhaust-producing agents such as automobiles, trucks, incinerators and the like has created threatening problems with respect to contamination and pollution of out environment. A significant amount of pollution of the atmosphere is derived from the existance of great numbers of internal combustion engines which are operated without any efficient control of the exhaust gases being emitted therefrom. Although not intended to be so limited, for convenience of illustration, the pollution control apparatus of this invention is described for use in the control of the exhaust gases of such internal combustion power plants.
Generally, the exhaust from an internal combustion engine such as that used in an automobile includes certain pollutants such as carbon monoxide, hydro carbons, carbon particulates, lead substances, sulfur and numerous other combustion products. In the prior art, countless techniques have been attempted to control and eliminate the harmful effects of exhaust gases and other polluted fluids. Previous devices have involved various mechanical, electronic and chemical processes in order to accomplish the desired elimination of pollution.
Although a great deal of research and development has gone into the field of pollution control, none of the prior art techniques has achieved the desired degree of efficiency and reliability to overcome the serious pollution problem. Previous attempts of relying on electronics to remove or convert undesired substances from an exhaust gas have presented several difficulties in achieving satisfactory results. For example, some of these devices have operated in a successful manner to remove one contaminant from the exhaust gas but which at the same time fail to remove other detrimental products. In order to accomplish the satisfactory removal of most of the contaminants, these electronic devices have required relatively complex equipment which are not only expensive but could not be depended on to produce satisfactory results over extended periods of time.
The prior methods of utilizing chemical properties such as catalysts and the like to remove pollution also present numerous problems. For example, the chemical reactants used to remove undesired products are consumables and must be uneconomically and inconveniently replaced at regular intervals. Moreover, it has been found that catalysts are greatly dependent on the degree of pollution in the exhaust in order to achieve optimum results and if an automobile is not properly tuned in performance, poor pollution control is accomplished. Chemical pollution control therefore involves expensive techniques which are not altogether satisfactory in practice.
Another mode of pollution control has been attempted which relies on a spark gap or corona to create ozone within an exhaust gas. Although some carbon monoxide is converted to carbon dioxide in these systems, the intensity of the ozone field has not been of the degree necessary for optimum removal of carbon monoxide. Moreover, such prior apparatus has failed to remove many of the other harmful contaminants present in an exhaust gas. The use of corona emission in such known devices also effects ionic charging of particles such as carbon in the exhaust to cause adherence of the particles to the corona producing elements before the material can be effectively destroyed. Such adherence of particles to the corona producing elements also reduces the effectiveness of the corona field as well as requires frequent cleaning of the elements.
The afore-mentioned mechanical pollution control techniques appear to have little or no effect in eliminating the dangerous and harmful components which are emitted from an internal combustion engine. Therefore, it is desirable to provide a pollution control method and apparatus which efficiently removes a great proportion of the contaminants of an exhaust gas in a manner which is both reliable in operation and economical in cost and maintenance.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to improve the removal of pollution from exhaust and waste fluids.
Another object of this invention is to eliminate a majority of the pollutants within an exhaust fluid in a simplified and economical manner.
A further object of this invention is to control and eliminate pollution by subjecting the exhaust fluid to an intense corona-producing chamber.
Still another object of this invention is to effectively increase the intensity of corona formed in a pollution removal chamber.
A still further object of this invention is to increase the control of pollution by subjecting the exhaust material to corona-producing elements coupled to an alternating electrical potential.
These and other objects are attained in accordance with the present invention wherein there is provided a pollution control apparatus which subjects the contaminated material to an extensive corona field. The exhaust gas is mixed with an oxygen-containing gas such as atmospheric air and the mixture subsequently passes through the novel corona-producing chamber of the invention. Corona emission is produced within the chamber by applying an electrical potential across two spaced conductive members to cause ionization of the gas and thus a glow discharge. The corona produced within the pollution removal chamber creates a plasma-like field which operates to effect a multitude of various chemical reactions on the gas passing through the apparatus. For example, the creation of corona creates an ozone field within the entire chamber which acts to convert harmful carbon monoxide into carbon dioxide. Moreover, the pollution elimination chamber of the apparatus effectively oxidizes carbon, carbon particulates, and sulphur; converts lead material into a relatively safe ash, burns away smoke, oil, and the like; and produces other pollution control operations.
The corona-producing members of the pollution control chamber include a plurality of elements having numerous corona emitting points which create an intense corona field within the entire volume of the chamber. Such members in the pollution elimination chamber are coupled to the opposite terminals of an alternating electrical potential. The alternating polarity of the corona producing elements prevents precipitation of charged particulates and adherence thereof to the structure of the chamber and also maintains any ionized substances moving and reactive. Thus particulates such as carbon and ash resulting from combustion are forced to pass through the entire elongated corona field to result in their substantial destruction. Such a result is not possible in prior D-C type corona devices in which the particles tend to adhere to the emitter before complete conversion. The invention allows particles such as carbon and the like to pass through the elongated pollution elimination chamber without being attached to the corona elements and thus the particles are subjected to the corona produced plasma for a length of time sufficient to completely oxidize, combust or convert the material.
Also, the reliance on a corona induced by an A.C. voltage not only creates a more intense corona than possible with a direct current voltage but also alleviates the necessity of periodically cleaning the pollution chamber and its associated elements. The present invention provides a pollution control apparatus which economically reliably converts the various contaminants of an exhaust gas and the like to a relatively safe form in an effective manner.
DESCRIPTION OF THE DRAWING
Further objects of the invention together with additional features contributing thereto and advantages accruing therefrom will be apparent from the following description of several embodiments of the invention when read in conjunction with the accompanying drawing wherein:
FIG. 1 is a schematic illustration of a pollution control apparatus of the invention;
FIG. 2 is a schematic end illustration of one embodiment of the corona-emitting member and support for use in the pollution control apparatus of FIG. 1;
FIG. 3 is a schematic side illustration of the corona-emitting member of FIG. 2;
FIG. 4 is a schematic end illustration of another embodiment of the corona-emitting member for use in the pollution control apparatus of FIG. 1;
FIG. 5 is a schematic side illustration of the corona-emitting member of FIG. 4;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown a schematic view of a pollution control apparatus 1 for eliminating pollution of an exhaust gas according to the present invention. The exhaust fluid is introduced into the apparatus through an inlet fitting 2 which is adapted to be coupled to an exhaust gas producing source such as the exhaust manifold of an internal combustion engine (not shown). The inlet fitting is conveniently formed in the shape of a tubular Y connector made of a suitable heat resistant material such as, for example, iron and the like. A first leg 3 of inlet fitting 2 is coupled to the exhaust line by any conventional pipe coupling technique such as interengaging threads to insure the introduction of the exhaust without leakage. The connection may be made at any point downstream the exhaust emission of the engine prior to or after the exhaust passes through the muffler of the vehicle.
The second leg 4 of the inlet fitting is attached to a source of oxygen-containing gas such as air to effect a mixing of the air with the exhaust gas to provide a proper amount of oxygen within the exhaust. In FIG. 1, there is shown a conventional air fan 5 which creates a flow of air into the system, although it is within the scope of the invention to utilize other means to introduce air into the system such as by air scoops mounted on the vehicle to create a ram effect, flow created by the fan of the vehicle, and other suitable sources. If the pollution control apparatus of the invention is utilized upon a vehicle such as an automobile, the air fan may be of a well known variable speed type in which the amount of air introduced into the apparatus is controlled by the power output of the engine to which it is coupled to insure proper pollution control. For example, the variable speed blower can be controllably connected to the accelerator linkage in a well known manner or may be attached to a tachometer sensor. Alternatively, the air may be introduced through a variable opening such as louvers whose degree of opening is dependent on the power output of the engine.
End 2' of the inlet fitting coupled to the upstream end of a tubular conduit 6 forming the pollution elimination chamber 7 to conduct the mixture of air and exhaust formed within the Y connector into the chamber. The inlet fitting is attached to conduit 6 by any suitable technique which provides a fluid-tight connection and further provides thermal and electrical insulation between the two elements. Such a coupling may comprise, as illustrated in FIG. 1, abutting flanges 8 and 8' attached together by any suitable means (not shown) and having an insulative material 8a such as Transite imposed therebetween.
Tubular conduit 6 forms the inner periphery of the pollution elimination chamber 7 and is made of an electrically conductive material to act as a reactor wall for producing a corona emission in the chamber. Although the conduit is described as being tubular, the element may encompass other shapes if desired. A casting 9 of a suitably insulative material such as Transite having both thermally and electrically insulative properties is mounted in surrounding relation to conduit 6 to isolate the element. Preferably, to insure the complete insulation of the pollution elimination chamber, the insulative casting extends for a length greater than the length of conduit 6.
The downstream end of conduit 6 is coupled to an outlet conduit 10 which directs the exhaust gas having passed through the pollution elimination chamber to the muffler, the atmosphere or any other location. The outlet conduit 10 is attached to the conduit 6 in a similar manner as described in reference to the upstream insulative coupling between inlet fitting 3 and the conduit. Thus, it should be apparent that the insulating material at the entrance and the exit of conduit 6 and the surrounding insulative casing 9 thermally and electrically isolates the pollution elimination chamber.
a corona-emitting member 20 is positioned within conduit 6 to effect a corona emission within the chamber. The corona-emitting member includes an elongated rod 21 formed of a suitable conductive material such as aluminum and extends a length longer than conduit 6. As shown in FIGS. 1 and 2, the rod of the corona-producing member may be supported by means of two X-supports 22 constructed with an electrically insulative and heat resistance material and which position the rod at the centerline of conduit 6 along the longitudinal axis thereof.
A plurality of space conductive discs 23 formed on rod 21 or press fitted thereto are positioned along the rod in a parallel relationship to create corona emitting areas. The number of discs utilized is dependent on the desired intensity of corona emission which is selected according to encountered conditions such as the amount of pollution within the exhaust gas, the relative proportion of the component pollutants therein and the like. A corona emission is created within the pollution elimination chamber by electrically coupling rod 21 of the corona-emitting element to one terminal 24 of an externally positioned source H.V. of alternating electrical potential and also electrically coupling conduit 6 to the other terminal 25 of the potential. The biasing of the two spaced conductors creates a corona discharge therebetween due to the small surface area of the periphery of discs 23. The electrical connection between the corona emitter and the potential includes an insulative connector 26 which passes through a suitable opening 27 formed in inlet fitting 2 and casing 9. If the pollution apparatus of the invention is utilized on a vehicle, an alternating potential may derive from the electrical power of the vehicle through the use of suitable well known circuitry methods.
In operation of the pollution control apparatus of FIG. 1, the exhaust gas and oxygen containing air is mixed in the inlet fitting 2 and the mixture passes into the pollution elimination chamber. Upon entering the pollution elimination chamber, the exhaust fluid is subjected to an intense corona field substantially for entire length of conduit 6 as the gas flows therethrough. The existence of oxygen within the exhaust stream and the creation of a corona emission produces a corona-ozone field throughout the chamber to convert carbon monoxide to carbon dioxide. Further, the high intensity corona operates to oxidize substantially all the carbon or carbon particulates existing in the gas, since the corona created by an A.C. potential prevents the adherence of carbon particles or other substances to the reactor wall or corona emitter. Thus, the pollutant materials must traverse the entire length of the chamber or until their complete conversion to carbon dioxide, and water vapor or to another relatively safe form. Such a technique results in effective pollution elimination with no moving parts in the apparatus or any consumable chemicals therein.
Moreover, lead substances emitted by the exhaust gas have found to be completely oxidized in the chamber or at least converted to a harmless ash. Smoke, oil, sulfur and other pollutants are likewise effectively oxidized or reduced to other forms through the inventive technique disclosed herein. Thus, it should be apparent that the complex oxidizing plasma created by the intense corona discharge within the pollution elimination chamber effects a multitude of chemical reactions which pass a relatively safe exhaust to the atmosphere or other location. Although not necessary, a suitable filter F material may be positioned in outlet conduit 10 to remove any combustion products such as ash which were not completely eliminated within the chamber.
Referring now to FIGS. 2 and 3, there is shown an embodiment of the invention which significantly intensifies the corona emission created within pollution elimination chamber of FIG. 1. In the embodiment of FIGS. 2 and 3, the periphery of the discs are formed with a star-like or serrated edge 30 instead of a smooth surface shown in FIG. 1. The points 31 of such a design creates sharp edges which effect a greater and more intense corona emission therefrom. Accordingly, the corona emission member 20 is significantly more effective in causing the desired plasma field within pollution elimination chamber 7.
Referring now to FIGS. 4 and 5, there is illustrated another embodiment of the corona-emitting member 4 for use in the pollution elimination chamber. The member 40 is mounted within conduit 6 in the same manner as the previous embodiments. The corona emitting member 40 of FIGS. 4 and 5 operate on the same principle as that described in reference to the embodiment specifically shown in FIGS. 1, 2, and 3. However, the form of the disc-like members has been modified in the embodiment of FIGS. 4 and 5 to create more surface points for a given length of the chamber to generate a greater intensity of corona within the chamber. Such greater intensity is achieved by forming element 41 in a dish or cup shape which includes periphery 42 having a star-like or serrated configuration to create surface points 43. One dish-like element 41 is placed in contact with an oppositely disposed complementary dish element 41' when positioned on rod 21. The points 43 on the periphery of element 41 are designed to engage and overlap the periphery of other element 41' so that the points 43 and 43' of each interengage in complementary relation and extend beyond the opposite member. It should be apparent, therefore, that the existence of additional surface points for a given length of the corona member as in the embodiment of FIG. 4 increases corona emission for effective control pollution.
In the above description, there has been disclosed an improved apparatus for controlling and removing pollutants from an exhaust gas. For convenience of illustration the pollution control apparatus was described for use in combination with an internal combustion engine but it is within the scope of the invention to utilize the inventive techniques of pollution control to eliminate pollutants from other sources such as diesels, aircraft, industrial smoke stacks, sewer gases, and numerous other applications. Further, the corona emitting elements were described as being a plurality of members mounted on the central support rod but it should be apparent that the emitting elements could also be in the form of convolutions around the rod and the like. In the preferred embodiment, the corona-producing element was disclosed as being coupled to an A.C. voltage, but it is possible to utilize the improved corona generating elements in conjunction with a D.C. potential under certain encountered circumstances.
While the invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teaching of the invention without departing from its essential teachings.
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A apparatus for controlling the amount of polluting substances within a fluid such as the exhaust gas of an internal combustion engine, wherein the polluted fluid passes through a corona-producing chamber having spaced conductive members biased by an alternating electrical potential which effect elimination or conversion of the harmful substances within the exhaust through a series of chemical reactions. Prior to passing through the corona-producing chamber, the exhaust gas is mixed with air or other oxygen containing substance to create an ozone field and other chemical reactants within the chamber to reduce the amount of various contaminants of the polluted gas. The corona-producing member is provided with a plurality of corona-emitting elements which cause an intense corona discharge to occur within the chamber.
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BACKGROUND OF THE INVENTION
This invention relates to thermal and noise insulation of the axial end walls of heated or cooled temperature controlled cylinders, as for example the type of rotatable cylinders used in the paper manufacturing industry, wherein a web of paper material passes over the peripheral convex surface of a heated dryer cylinder and absorbs heat from the cylinder.
In the process of manufacturing paper products, wet paper is moved in a web across a plurality of heated cylinders, and the heated cylinders progressively dry the paper which eventually emerges as a dryer product. The dryer cylinders vary in length and in diameter, but a common range of lengths and diameters of dryer cylinders would be between 1 and 40 feet in length and between 1 and 30 feet in diameter. The normal rotational velocity of operating dryer cylinders is between 100 and 10,000 surface feet per minute, and a common temperature range for dryer cylinders would be between 100° F. and 600° F.
The dryer cylinders can be heated from various heat sources, with a common heat source being superheated steam at a temperature sufficient to heat the cylindrical convex surface of the dryer cylinder to the desired temperature. The steam is transmitted under pressure through the axles of the dryer cylinders to heat the inside of the dryer cylinders.
Since the web of paper makes continuing contact with the external convex surface of the dryer cylinder wall during the operation of the dryer cylinder, a major portion of the heat applied to the cylindrical wall of the dryer cylinder is absorbed by and taken away by the paper; however, the web of paper does not contact the axial end walls of the dryer cylinder, and the heat from inside the dryer cylinder that is transferred through the axial end walls is lost to the atmosphere.
Some attempts have been made to insulate the axial end walls of heated dryer cylinders. For example, U.S. Pat. No. 2,571,426 discloses the mounting of a heat insulating asbestos disc to the inner face of the axial end wall of a dryer cylinder, while U.S. Pat. No. 4,241,518 discloses clamping semi-circular panels to the connector bolts of the axial end walls of a dryer cylinder. While it appears that the attachment of insulation structures to the internal surfaces of the axial end walls of a dryer cylinder would function to retard the loss of heat from a dryer cylinder, it appears that such a structure would be difficult to install and would be hidden from inspection unless the manhole cover was removed from the dryer cylinder. While it appears that external heat shields could be applied to the external surfaces of an axial end wall of a rotatable dryer cylinder by attaching the heat shields to the bolts that attach the axial end wall to the cylindrical wall, it is undesirable to do so since the bolts must contain the axial end wall in position against the pressure of the high pressure superheated steam within the dryer cylinder and the loosening or otherwise adjusting of the bolts might result in a safety hazard due to the bolts parting from the dryer cylinder during rotation or due to steam leakage between the cylindrical wall and the axial end wall of the dryer cylinder. Additionally, many of the dryer cylinders which contain fluid under pressure are regulated by ASME pressure vessle codes which limit the use of the connector bolts for purposes other than connecting the end wall to the cylindrical wall of the assembly.
The use of nonflexible rigid insulator panels with the axial end walls of temperature controlled rotatable cylinders apparently requires the insulator panels to be constructed for a particular end wall shape so the nonflexible insulator panels in some instances would be usable for only one model dryer cylinder, and the rigid insulator panels apparently would require that the panels be formed in a multiple number of parts that would have to be assembled about the axle of the dryer cylinders when being applied to the axial end wall of the dryer cylinder in its plant operating configuration.
The usual construction of a heated dryer cylinder for use in a paper making process is to have the axial end wall formed in a precision fit with respect to the cylindrical wall of the dryer cylinder. The connector bolts can be tightened in a pattern to draw the axial end wall onto the cylindrical wall, and when the axial end wall is to be removed from the cylindrical wall, the connector bolts are loosened and threaded jack screw openings usually are present in the axial end wall so that externally threaded jack screws can be rotatably inserted into the jack screw openings to bear against the end of the cylindrical wall and progressively push the axial end wall off the cylindrical wall. When the axial end wall is properly mounted on the cylindrical wall and the dryer cylinder is ready for normal operation, the jack screws usually are removed from the jack screw openings of the axial end wall.
SUMMARY OF THE INVENTION
Briefly described, the present invention comprises a lightweight plyable end panel heat and noise insulator assembly for a paper machine dryer cylinder, or for a similar heated or cooled cylindrical structure, which includes an annular one-piece flexible insulation blanket that defines a central opening and an approximately circular outer periphery and a split or slot extending from the inner opening to the outer periphery, whereby the insulator blanket can be positioned about the axle of a rotatable dryer cylinder and positioned in abutment with the axial end wall of the dryer cylinder when the cylinder is in its plant operating configuration. In one embodiment inner and outer mounting rings are rigidly connected to the inner and outer portions of the axial end wall of the dryer cylinder, and the annular blanket is connected at its inner and outer peripheries to the inner and outer mounting rings. In other embodiments the blanket can be mounted to the axial end wall by adhesive, by the use of a combination of an inner or an outer mounting ring with radially extending stays, and/or with adhesive.
The insulation blanket is fabricated from one or more layers of heat insulation material, such as rockwool or fiberglass, and the blanket includes an outer durable, substantially heat resistent cover, such as woven Nylon sheet material coated with Neoprene, or Nomex, Teflon, Kevlar or Viton sheet material. Additionally, one or more layers of relatively unstretchable material can be included among the layers of heat insulation and heat resistent materials, with the relatively unstretchable material being, for example, wire screen or woven sheets of Nomex, Kevlar Viton yarns. The multiple layers of the insulator blanket are connected to each other by stitching extending through the layers of blanket material and by grommets, and the stitching is arranged to form pockets in the blankets, as for example in approximately concentric annular patterns about the central opening of the insulator blanket with the annular patterns including both annular stitching and radial stitching to form a quilted arrangement of pockets. The pockets tend to hold the insulator material in place, and this prevents the insulator material from acumulating in some areas and leaving a void in other areas and retards the breakdown of the fibers of the insulator material.
In the embodiment that includes inner and outer mounting rings, the outer mounting ring of the end panel insulator assembly is rigidly connected to the axial end wall of the dryer cylinder by means of mounting screws connected to the outer mounting ring and threadably engaging the threads of the jack screw openings or other threaded openings of the axial end wall of the dryer cylinder. The inner mounting ring is clamped to the central protrusion of the dryer cylinder, and the outer and inner peripheral portions of the dryer blanket each include a series of grommets or similar openings which normally overlie the outer and inner mounting rings, and connectors connect the grommets to the mounting rings. Flexible stays can be included so as to extend radially from the central opening of the blanket outwardly to the outer peripheral edge portion, with grommets formed through the ends of the stays and the material of the insulator blanket. Also, the blanket can be applied directly to the exterior surface of the axial end wall with adhesive, if desired. The adhesive connection of the insulator blanket can be used alone or in combination with the other blanket connection features, as might be suitable for a particular cylinder structure.
Thus, it is an object of this invention to provide a flexible lightweight, durable end panel insulator assembly for mounting to the exterior surface of the axial end wall of a temperature controlled cylinder such as a heated dryer cylinder for a paper making process without using the connector bolts extending from the axial end wall to the cylindrical wall of the cylinder.
Another object of this invention is to provide an end panel insulator assembly for a temperature controlled cylinder which includes a replaceable insulator blanket fabricated in one piece and which is fabricated of flexible material, which is lightweight and which can be expediently installed and removed.
Another object of this invention is to provide an end panel insulator assembly for mounting to the exterior surface of the axial end wall of a temperature controlled cylinder which, when rotated, is safe in operation and which is effective to retard the transfer of heat through the cylinder end walls.
Another object of this invention is to provide an end panel insulator assembly for a temperature controlled cylinder, which is adaptable to various axial end wall contours, such as concave or convex end walls due to its flexibility.
Other objects, features and advantages of the present invention will become apparent upon reading the following specification, when taken in conjunction with accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective illustration of an axial end wall and a portion of a cylindrical wall of a dryer cylinder, and shows the end panel insulator assembly exploded away from the dryer cylinder.
FIG. 2 is a side elevational view of one-half of the end panel insulator assembly and the axial end wall of a dryer cylinder.
FIG. 3 is a detail illustration of the outer mounting ring and the standoff bolt structure at a position on the mounting ring where the mounting ring is not split.
FIG. 4 is a detail illustration similar to FIG. 3, of the mounting ring and standoff bolt structure, at a location on the mounting ring where the mounting ring halves are joined.
FIG. 5 is an end view of the mounting ring of FIG. 4.
FIG. 6 is a side cross-sectional view of a cam connector and of a grommet, showing how the outer peripheral portion of the insulator panel can be connected to the outer mounting ring.
FIG. 7 is a side elevational view of one-half of the end panel insulator assembly, similar to FIG. 2, but illustrating an embodiment of the invention that includes internal rigidifying stays.
FIG. 8 is a detail end view of the embodiment of FIG. 7, showing the ends of the stays.
FIG. 9 is a detail end view of the end panel insulator assembly, similar to FIG. 2 but illustrating an embodiment of the invention that includes a flap that covers the grommets and drawstrings of the slot in the insulator blanket.
FIG. 10 is a side cross-sectional view of one-half of an end panel insulator assembly, similar to FIG. 2, but illustrating an embodiment of the invention that includes an inner mounting ring but no outer mounting ring, and adhesive connection between the insulator blanket and the outer surface of the axial end wall of the cylinder.
FIG. 11 is a side cross-sectional view of one-half of an end panel insulator assembly, similar to FIGS. 2 and 10, but illustrating an embodiment of the invention in which the insulator blanket is adhesively mounted to the axial end wall of the cylinder without mounting rings.
DETAILED DESCRIPTION
Referring now in more detail to the drawings, in which like numerals indicate like parts throughout the several views, FIG. 1 illustrates a rotatable heated dryer cylinder 10 which includes a convex outer cylindrical wall 11 and axial end walls 12 (only one shown) which close the ends of the cylindrical wall 11. Typically, one axial end wall 12 of the dryer cylinder will include an annular surface 13 which is coextensive with the outer convex surface of cylindrical wall 11 that extends as a flange or rim 14 and the axial end wall 12 is recessed within the rim. The other end of the dryer cylinder may be structured differently, without the overhanging rim. An axle 15 extends centrally from the end wall 12, from protrusion 16 of the end wall, and the dryer cylinder is mounted at opposite ends on axles 15. The axles 15 include openings 18 extending therethrough, and steam communicates with the inside of the dryer cylinder 10 through the openings 18 in the axles 15.
The axial end wall 12 is rigidly connected to the cylindrical wall 11 by the axial end wall 12 bearing against the end annular edge 19 (FIG. 2) of the cylindrical wall 11. An internal protrusion 20 formed on the axial end wall 12 fits within the confines of the end annular edge 19 of the cylindrical wall 11, and threaded bores (not shown) are formed in the end annular edge 19 of the cylindrical wall 11. Holes 21 (FIG. 1) are formed in axial end wall 12 and the holes 21 are spaced and sized so as to register with the threaded bores. Screws 22 extend through the holes 21 and are threaded into the bores of the cylindrical wall so as to rigidly connect the axial end wall 12 to the cylindrical wall 11 in a tight fit.
Jack screw openings 24 usually are located at 90° intervals about axial end wall 12 between the screws 22. When the axial end wall 12 is to be removed from the cylindrical wall 11, the screws 22 are first removed from the structure, and then jack screws (not shown) are threaded into the jack screw openings 24, and when the jack screws engage the end annular edge 19 of the cylindrical wall 11, the jack screws push the axial end wall 12 away from the cylindrical wall 11. When the dryer cylinder 10 is completely assembled and ready for operation, the jack screws are removed from the jack screw openings. This is conventional in the art.
In the embodiment of the invention illustrated in FIGS. 1-6, end panel insulator assembly 25 is mounted to the axial end wall 12 of the dryer cylinder 10, and the end panel insulator assembly includes inner mounting ring assembly 26, outer mounting ring assembly 28, and annular insulator panel or blanket 29.
Inner mounting ring 26 comprises a pair of half rings 30 and 31 that are to be assembled in a circular configuration by placing their end portions in abutment with each other. Connector screws 32 extend through openings 34 and 35 adjacent the ends of the half rings, with opening 35 including threads for engagement with the threads of the screw 32. The screws 32 draw the half rings together in a clamped relationship. The opening 36 formed by the two half rings 30 and 31 is slightly smaller than the external annular dimensions of the protrusion 16 of axial end wall 12, so that when inner mounting ring assembly 26 is loosely placed about protrusion 16 and its screws 32 rotated to draw the half rings 30 and 31 together, a tight friction fit is formed by the inner mounting ring assembly 26 against the protrusion 16 of the axial end wall 12. A plurality of internally threaded connector openings 38 are formed in the inner mounting ring assembly 26.
Outer mounting ring assembly 28 includes a pair of half rings 40 and 41 which are normally arranged as indicated to form a circular shape. The end portions 42 of each half ring 40, 41 is undercut at 44 and support blocks 45 are sized and shaped to fit in the undercut portions 44. Support blocks 45 each include a centrally positioned unthreaded standoff hole 46, and a pair of internally threaded connector holes 48 positioned on opposite sides of the standoff hole 46. Unthreaded connector holes 49 also extend through the end portions 42 of the half rings 40 and 41, and screws 47 are inserted through the unthreaded connector holes 49 and into the internally threaded connector holes 48, thus connecting the support blocks 45 to the ends of the half rings 40 and 41 and rigidly connecting the half rings together to form the complete outer mounting ring assembly.
The half rings 40 and 41 of the outer mounting ring assembly 28 includes a series of equally spaced mounting holes 50. Also, standoff holes 51 are located intermediate the ends of the half rings 40 and 41. The standoff holes 51 are located across from each other in the outer mounting ring assembly 28 while the standoff holes 46 of the support blocks 45 are located across from each other in the ring assembly, with the standoff holes 46 and 51 being located usually at 90° intervals about the outer mounting ring assembly 28.
The outer mounting ring assembly 28 is sized and shaped to span the jack screw openings 24 of the axial end wall 12 of the dryer cylinder 10, and the standoff holes 46 and 51 of the outer mounting ring assembly 28 are alignable with the jack screw openings 24. Standoff studs 54 each includes a shank that includes a threaded portion 55 at its distal end, and intermediate enlarged boss 56, and hexagonal head 58. A pilot extension 57 is centrally located on the exterior surface of hex head 58, and an internally threaded bore 59 extends inwardly from the pilot extension of hex head 58. Each standoff stud 54 is arranged to be threaded into a jack screw opening 24, with the boss 56 limiting the penetration of the stud in the jack screw opening. This locates the threaded bore 59 of each standoff stud 54 at 90° intervals about the axial end wall 12 of the dryer cylinder, and the standoff holes 46 and 51 of the outer mounting ring assembly 28 are alignable with the threaded bores 59 of the standoff studs 54. Connector screws 60 extend through the unthreaded standoff holes 46 and 51 and are threaded into the bores 59 of the standoff studs 54, thus mounting the outer mounting ring assembly 28 to the axial end wall 12 of the dryer cylinder 10. Since the standoff studs 54 have their heads 58 displaced from the axial end wall 12 of the dryer cylinder, the outer mounting ring assembly 28 also is displaced from the surface of the axial end wall 12, at a position juxtaposed the screws 22 that connect the axial end wall 12 to the cylindrical wall 11 (FIGS. 3 and 4).
Insulator panel 29 is annular shaped and defines central opening 61 and includes an inner peripheral portion 62 and an outer peripheral portion 64. A slit or slot 65 is formed in insulator panel 29 and extends from the central opening 61 through the outer peripheral portion 64. Grommets 66 are positioned on opposite sides of the slot 65 and extend through the material of the insulator panel 29, and cords 68 are extended through the grommets 66 in a conventional manner to hold the slot in a closed configuration. The edge portions of the insulator panel about slot 65 are shaped so as to overlap when the slot is drawn closed by the cords 68. Thus, the grommets 66 and cords 68 function as a means for closing the slot 65.
The inner and outer peripheral portions 62 and 64 of insulator panel 29 include a series of grommets 70 that are spaced apart a distance corresponding to the spacing of the mounting holes 50 of outer mounting ring assembly 28 and the mounting holes 38 of the inner mounting ring assembly 26. Cam connectors 71 (FIG. 6) extend through the grommets 70 and into the mounting holes 38 and 50 of the inner and outer mounting ring assemblies 26 and 28. The mounting holes of both the inner and outer mounting ring assemblies 26 and 28 are counter bored, as illustrated at 72 of FIG. 6, with the mounting holes being internally threaded. Eccentric bushing 74 includes axial central opening 75 that extends therethrough and boss 76 that is sized and shaped to be received in the counter bore 72 of each mounting hole 38, 50. Eccentric cam 78 is formed adjacent boss 76 and is sized and shaped to fit within the opening of the grommet 70, and head 79 extends beyond the overhangs eccentric cam 78. Screw 80 extends through central opening 75 of eccentric bushing 74 and is threaded into the mounting holes 38, 50. When screw 80 is loosely connected to the mounting holes 38, 50, its eccentric bushing 74 can be rotated and its cam 78 will cause relative movement between its grommet 70 and the mounting holes 38, 50, so as to shift the positions of the peripheral portions 62, 64 of the insulator panel 29. This permits the installer to adjust the positions of the grommets, in order to accommodate slight misalignments of the grommets with the mounting holes, and to tighten the insulator panel.
As illustrated in FIG. 2, the insulator panel 29 comprises an outer covering 81 formed from a heat and water-resistent material such as a Nylon sheet coated with Neoprene, Teflon, or Hyperlon and an inner filler material 84 of a heat insulating substance, such as fiberglass, rockwool or foam insulator panels. The heat insulation material 84 is formed in layers, and relatively unstretchable material 82, such as wire screen or woven Nomex, is positioned between the insulation layers. Preferably the strands of the sheets of relatively unstretchable material are not oriented parallel to the strands of adjacent sheets of unstretchable material so that any weakness of one sheet in a bias direction of its strands is compensated for by another sheet. Both the insulation layers and unstretchable layers extend from the inner peripheral portion 62 to the outer peripheral portion 64. Stitching 85 extends through the insulation panel 29 and connects together the layers of insulation material 84 and the intervening layers of relatively unstretchable material 82. The stitching 85 is formed in approximately concentric annular patterns and in radial patterns about the central opening of the insulator panel. The stitching 85 forms pockets that tend to retard any shifting of material.
A pair of concentric seals 86 and 88 are formed on the inner surface of the insulator panel 29. The inner concentric seal 86 is positioned closely adjacent the central opening 61 of the insulator panel 29 while the outer concentric seal 88 is positioned next adjacent the outer peripheral portion 64. The seals 86 and 88 are formed in the shape of annular ribs and each comprises inner heat insulation material such as fiberglass and outer heat resistant material such as Nomex. Vent openings 89 are formed through the seals 86 and 88, with the vent openings comprising tubes extending radially through the seals. The vent openings permit any moisture that may be trapped adjacent the exterior surface of the axial end wall 12 to escape.
The insulator panel 29 as described herein, is formed in one piece from relatively flexible material and functions as a insulator blanket to retard the escape of heat from the exterior surface of the axial end wall 12 of the dryer cylinder 10. The flexibility of the insulator panel permits the slot 65 to be opened so that the slot can be installed about the axle 15 of the dryer cylinder, and the slot can then be held closed by inserting the cords 68 through the grommets 66 on opposite sides of the slot.
One of the axial end walls 12 of the dryer cylinder 10 usually includes an access opening (not shown), and cover plate 90 is normally bolted over or otherwise secured over the access opening. In order that the access opening and cover 90 can be reached without removing the end panel insulator assembly 25 from the dryer cylinder 10, the slot 65 can be opened to reach the access opening, or in the alternative, an access opening 91 can be formed in the insulator panel 29 and a flap 92 extended over the opening 91. In this embodiment grommets 94 are located adjacent the edges of the flap 92 and adjacent the access opening 91 and cords 95 connect the grommets together to maintain the closure flap 92 in its closed configuration. It will be noted that the distal edge 96 of the closure flap 92 is located away from the central opening 61 of the insulator panel, so that centrifugal force applied to the closure flap 92 due to the rotation of the insulator panel 29 with the dryer cylinder 10 normally urges the closure flap toward its closed position.
As illustrated in FIGS. 7 and 8, a plurality of stays 96 can be included as a part of the insulator blanket. In the embodiment illustrated, metal stays 96 extend radially from the inner peripheral portion of the blanket adjacent central opening 61 to the outer peripheral portion 64, and grommets 70 are attached to and form openings through the end portions of the stays. The stays 96 of FIGS. 7 and 8 are illustrated as being positioned within the blanket; however, the stays can be located externally of the blanket (not shown), as by inserting the stays through loops attached to the surface of the blanket. Preferably, the stays are formed so that they are adjustable in length, by forming the stays in two sections 96a and 96b, with alignable connector opening 97 formed in their overlying portions, whereby the stays can be lengthened or shortened and bolts inserted through aligned ones of the openings 97. The stays are formed of a length slightly longer than the radial distance between the openings of the inner and outer mounting ring assemblies 26 and 28, so that the stays tend to bow inwardly toward the axial end wall 12 of the dryer cylinder, thus urging the insulator blanket and its seals 86 and 88 toward engagement with the axial end wall.
As illustrated in the embodiment of FIG. 9, the slot 65 can include a closure flap 98 that extends from one side to the other side of the slot and covers the cords 68. Velcro strips 99 and 100 are attached to the edge of flap 98 and adjacent slot 65, and when pressed together, tend to hold the flap in place over the cords. Additionally, snaps 101 are attached to the flap structure to assure that the flap remains closed when the insulator blanket is rotating. Preferably, the insulator blanket is installed so that the direction of rotation is opposite to the orientation of the flap, as indicated by arrow 102, so that the relative wind tends to hold the flap closed.
The flexibility of the insulator blanket permits the blanket to be installed about the axle of the dryer cylinder when the dryer cylinder is in its operational configuration. In the embodiment of FIGS. 1-7, the insulator blanket can be removed from the inner and outer mounting ring assemblies and replaced with another insulator blanket without requiring replacement of the mounting rings. The mounting rings can be attached to the axial end wall of the dryer cylinder without contacting the connector bolts 32 of the dryer cylinder, by attaching the outer mounting ring to the jack screw openings or to other tapped and threaded openings that can be formed in the axial end wall of the dryer cylinder.
As illustrated in the embodiments of FIGS. 10 and 11, the insulator blanket can be attached directly to the outer surface of the axial end wall with adhesive. In FIG. 10 the insulator blanket 105 includes an inner layer 106 of heat insulation material, inner cover layers 108 and 109 of thin, relatively nonstretchable heat resistant sheet material such as sheets of Nomex, Kevlar, or Viton with the heat insulation material. A durable outer cover is formed by woven Nylon sheets 110 and 111 coated with Neoprene, Teflon sheets, or Hyperlon. The inner peripheral edge portion 113 adjacent central opening 112 is mounted on inner mounting ring 26 with screws 114 extending through grommets of the insulator blanket and into the mounting ring. An adhesive coating is applied to the facing surfaces of the insulator blanket and the outer surface of the axial end wall of the cylinder to hold the insulator blanket to the cylinder. At the outer peripheral edge portion 115 a flap is formed to cover the heads of the connector screws 22, with the flap being secured about the heads of the connector screws to the axial end wall. The adhesive would be, for example, a high or low temperature resistant epoxy glue.
As illustrated in FIG. 11, the insulator blanket 105 is mounted directly to the surface of the axial end wall without the use of either inner or outer mounting rings. The inner peripheral edge portion 113 is applied directly to the axial end wall of the cylinder with the adhesive coating.
While the invention has been described in association with heated dryer cylinders for paper mills, it should be understood that the invention can be used with other temperature controlled cylinders, either heated or cooled. Moreover, it should be understood that the foregoing description relates only to preferred embodiments of the present invention and that numerous modifications or alterations may be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.
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A lightweight plyable heat and noise end panel insulator panel is mounted to the exterior surface of the axial end wall of a temperature controlled cylinder. The insulator panel comprises multiple layers of heat and noise insulation material and relatively non-stretchable material stitched and grommeted together whereby a pattern of pockets are formed to hold the fragile heat insulation in place. The panel defines a central opening and a slot extending from the central opening through the outer peripheral edge portion so that the panel can be positioned about the axle of the cylinder.
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BACKGROUND
[0001] When tracking an object using computer vision techniques, it can be desirable to place an active light emitting diode (LED) on the object to be tracked. Thus, the object can be tracked by tracking corresponding characteristics of the light source. This simplifies the image-processing task of finding the object in an image. It also reduces or eliminates ambiguity in terms of determining which object in an image is the object to be tracked. The tracking process can be simplified even further by using infrared (IR) LEDs and IR-sensitive cameras. In this case, the IR LED may be the only item visible in the scene.
[0002] Currently, the effectiveness of tracking an object by tracking an associated light source is limited because cameras are limited to a relatively low frame acquisition rate, such as a rate in the range of 30-60 Hz. Thus, such systems are generally unable to capture large or quick motions. Further, such systems typically exhibit high latency (latency is bounded by frame rate). Applications that might involve large and/or quick movements such as, but not limited to, music synthesis and video game controllers would benefit from higher frame rates.
[0003] The discussion above is merely provided for general background information and is not intended for use as an aid in determining the scope of the claimed subject matter.
SUMMARY
[0004] A computer-implemented method for utilizing a camera device to track an object is presented. As part of the method, a region of interest is determined within an overall image sensing area. A point light source is then tracked within the region of interest. In a particular arrangement, the camera device incorporates CMOS image sensor technology and the point light source is an IR LED. Other embodiments pertain to manipulations of the region of interest to accommodate changes to the status of the point light source.
[0005] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a schematic block diagram of one environment in which some embodiments may be practiced.
[0007] FIG. 2 is a block flow chart illustrating steps associated with tracking a point light source associated with an object.
[0008] FIG. 3 is a block flow diagram demonstrating steps associated with a process for handling object detection.
[0009] FIG. 4 is a schematic representation visually demonstrating a process for object detection.
DETAILED DESCRIPTION
[0010] FIG. 1 is a schematic block diagram of one environment in which some embodiments may be practiced. More specifically, FIG. 1 depicts a computer vision-based object tracking system 100 . It should be noted that the present invention is not limited to the computer vision system illustrated in FIG. 1 . System 100 is but one example of a suitable environment in which embodiments may be implemented. System 100 is not intended to suggest any limitation as to the scope of use or functionality of various embodiments. Neither should system 100 be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary environment.
[0011] System 100 includes a camera device 102 that, as is generally indicated by lines 104 , has a field of vision focused upon a portion of a surface 106 . Those skilled in the art will appreciate that the field of vision can be adjusted through manipulation of imaging components, such as through adjustment of the focus of one or more lenses. Such lenses may or may not be directly incorporated into camera device 102 .
[0012] In general, camera device 102 is configured to facilitate application of computer vision techniques to support a gathering of data related to the positioning of an object 108 . Surface 106 may be transparent such that object 108 is observable by camera device 102 when placed within the associated field of vision. Depending on the technical capacity of camera device 102 (e.g., ability to re-focus or change the field of view, etc.), the ability to track motion of object 108 may be limited to movements wherein object 108 is kept in relatively close proximity to surface 106 . However, depending on the technical capacity of camera device 102 , it is possible to eliminate surface 106 from the system completely such that the position of object 108 can be tracked at multiple distances from device 102 , including various distances other than the distance associated with surface 106 .
[0013] For any of a variety of reasons, such as to eliminate ambiguity in the object to be tracked, or to simplify the processing task of finding the target object in the image, a light source 110 (e.g., an LED) is added to object 108 . Camera device 102 then tracks object 108 by tracking light source 110 . In one embodiment, not by limitation, light source 110 is an IR LED and camera device 102 is an IR-sensitive camera. This even further simplifies the tracking of object 108 . Of course, surface 106 is assumed to be transparent to the light emitted from light source 110 .
[0014] The effectiveness of tracking object 108 by tracking light source 110 is at least partially contingent upon the frame acquisition rate supported by camera device 102 . For example, if the frame acquisition rate is in the range of 30-60 Hz, then camera device 102 will not likely be able to effectively capture large or quick movements of object 108 . Further, if the frame acquisition rate is low, then latency very well may be undesirably high because latency is generally bounded by frame rate.
[0015] Applications that might involve large and/or quick movements would benefit from support for higher frame rates. For example, systems designed to track input made upon a screen with an electromagnetic stylus have specified sample collection at 133 Hz to achieve smooth capture of strokes for handwriting recognition, drawing, etc. Other applications such as, but not limited to, music synthesis and video game controllers may also require a relatively high frame acquisition rate.
[0016] Camera device 102 is illustratively configured to increase or maximize the frame acquisition rate by exploiting sensor technology that enables specification of an active region of interest (ROI) in the overall image sensing area. In one embodiment, this is accomplished through implementation of Complementary Metal Oxide Semiconductor (CMOS) image sensor technology. CMOS imagers are effectively limited in the bandwidth of the connection link, not the light gathering electronics on the imager itself. Thus, the frame acquisition rate is related to the size of the ROI. A CMOS sensor capable of delivering 30 640×480 frames per second will deliver 4*30=120 frames per second with an ROI of 320×240. By reducing the ROI further, frame rates of several hundred Hz or more are possible.
[0017] The described approach raises a few issues to consider. First, because pixels are acquired more quickly than is typically the case, the light integration time for each pixel is relatively reduced. This is akin to reducing the “exposure time” of the camera device. It is possible that for small ROIs, everyday indoor scenes will be too dark to be imaged. Incorporation of an active LEDs into an item to be tracked addresses this issue. The brightness of the LED is apparent even at small ROIs.
[0018] Another issue to consider is that a small ROI may require active adjustment such that a tracked object will fall within it. In one embodiment, this issue is addressed by calculating an updated position of the ROI and sending the new ROI to the camera interface. Depending on the technical capacity of a given camera implementation (e.g., a given CMOS imaging system), this may involve a loss of one or more frames. To achieve the highest frame rate, the frequency of changing the ROI can be limited, which may in turn require a larger ROI than if changed every frame.
[0019] The present description is focused on one example environment wherein a camera is focused on a surface. In one embodiment, a light source implement is configured with a tip-switch such that the light source is active (e.g., the IR LED is on) only when the switch is on the surface. However, those skilled in the art that the same concepts described herein can similarly be applied within a surface-free environment, such as an environment wherein a light source is waved around in front of a camera for a game or some other purpose.
[0020] FIG. 2 is a block flow chart illustrating steps associated with tracking a point light source associated with an object. In accordance with block 202 , there is first a determination of an ROI within the overall image sensing area. As is indicated by block 212 , the boundaries of the ROI may be based on the potential for movement of the point light source. For example, areas that extend beyond where the light source could move prior to a subsequent re-determination of the region of interest need not be included.
[0021] In accordance with block 204 , the point light source is tracked within the determined ROI. Block 206 represents an updating or re-determination of the ROI. As noted, the boundaries can again be made contingent on potential for movement. The system can illustratively be configured to perform the re-determination step only under certain circumstances, such as periodically or only when the light source has moved (i.e., if it hasn't moved then re-determination is unnecessary). Further, as is indicated by block 212 , re-determination can be made contingent upon movement of the point light source beyond a predetermined threshold. For example, the threshold might be based upon how far movement could potentially occur within a given time period (e.g., a certain number frames, the period between re-determinations of the ROI, etc.). In one embodiment, the region is selected according to a model of the point's motion (e.g., linear motion prediction, Kalman filter, etc.). A better prediction of the point's location supports a smaller ROI and thus a higher frame rate. In accordance with block 208 , the updating and tracking steps can be repeated as necessary.
[0022] It worth pointing out that, with a small ROI, it may be unlikely that the system will detect the appearance of a new object to be tracked. In one embodiment, a specialized algorithm is employed to enhance the system's capacity to detect objects. FIG. 3 is a block flow diagram demonstrating steps associated with a process for handling object detection. In accordance with block 302 , when no object (i.e., no point light source) is being actively tracked with a small ROI, then the ROI is enlarged (e.g., to the maximum size). Of course, the frame acquisition rate will correspondingly decrease under the circumstances. In accordance with block 304 , expanded ROI is scanned until a new object (i.e., a new point light source) is detected.
[0023] In accordance with block 306 , upon detection of an object (i.e., the point light source), the ROI is reduced to cover only the object and a corresponding potential range of movement (e.g., the range over which it can move during the small frame time). If, after a time, the object (i.e., the point light source) is not detected in the small ROI, then the system reverts back to the detection phase (e.g., expanded ROI).
[0024] FIG. 4 is a schematic representation visually demonstrating a process for object detection. In a detection mode 402 , the ROI is expanded, the frame acquisition rate is relatively slow and latency is increased. This is assumedly prior to detection of a point light source associated with an object. Upon detection, the system transitions into tracking mode 404 , wherein the ROI is reduced, the frame acquisition rate is increased and latency is reduced. As has been described, in the tracking mode, the ROI is illustratively adjusted to accommodate movement of the object. Arrow 406 demonstrates that the system can switch between the detection mode and tracking mode as necessary.
[0025] As an example of a specific implementation, methods such as those described are employed to track the positioning of an active IR LED built into a stylus. Samples are collected at a frame acquisition rate measured in hundreds of HZ (e.g., more than 400 HZ). Thus, the stylus can be used effectively in an inking application. Furthermore, “sub-pixel” tracking techniques can be employed to further improve the quality of the inking functionality. This can be achieved, for example, by calculating the position of the LED as the weighted average of the position of the bright pixels in the ROI, where each weight is the brightness of the pixel.
[0026] Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.
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A computer-implemented method for utilizing a camera device to track an object is presented. As part of the method, a region of interest is determined within an overall image sensing area. A point light source is then tracked within the region of interest. In a particular arrangement, the camera device incorporates CMOS image sensor technology and the point light source is an IR LED. Other embodiments pertain to manipulations of the region of interest to accommodate changes to the status of the point light source.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to pre-stressed concrete. More particularly, it relates to methods of making tendons which are used primarily in post-tensioning of pre-stressed concrete.
2. Description of the Prior Art
In the process of pre-stressing concrete is by the technique of post-tensioning, it is important that the tendon be free to move within the hardened concrete so that the tensile load on the tendon is evenly distributed along the length of the tendon.
Various methods have been used in attempts to assure that the tendons used for post-tensioning concrete are capable of free movement within the hardened concrete. These methods include the laying of a number of parallel strands of wire in a metal duct or plastic tube and then stretching the strands after the concrete is hardened. The duct or tube is usually filled with grease after the strands are stretched. Also, a number of parallel strands of wire have been covered with grease and then covered with spirally wound paper. In some cases the spirally wound paper is replaced by spirally wound plastic. Another alternative to the paper wrapped tendon is the cigarette wrap or lap seam tendon. Tendons have also bee produced by stuffing or pushing a greased seven wire strand into and through a previously extruded plastic tube.
U.S. Pat. No. 3,646,748 discloses a post-tensioning tendon which comprises a multiple-wire strand encased in a corrosion inhibitor in an amount sufficient to provide a circular encasement around the strand of a diameter at least two mils greater than the diameter of the strand and having a seamless plastic jacket tightly covering the encased strand. A process for making such tendons is also disclosed.
All such prior tendons, however, suffer from one or more practical deficiencies such as high manufacturing cost, low reliability and a low level of assurance of trouble-free service. The present invention provides post-tensioning tendons which are without the deficiencies of the prior art.
SUMMARY OF THE INVENTION
The present invention provides a method of making a tendon suitable for use in the post-tensioning of concrete as well as for other applications. The method comprises the steps of coating a wire or a multiple-wire strand with a thin coat of a corrosion inhibitor. In the preferred embodiment, the thin coat may be more easily applied by coating the wire or multiple-wire strand with a thick coating of corrosion inhibitor and then removing the surplus amount of the corrosion inhibitor from the outer periphery of the strand, including the interstices, to leave the desired thin coat. A seamless plastic jacket is then formed around the wire or multiple-wire strand while simultaneously creating a differential pressure across the seamless plastic jacket such that the pressure in the volume defined by the seamless plastic jacket is greater than the pressure outside the seamless plastic jacket.
Among the advantages offered by the present invention is a resulting tendon which is low in cost of manufacture but still provides a tendon which is high in reliability and assurance of trouble-free service. The resulting tendon tends to not bleed grease through the ends of the tendon or through any pin holes which might occur in the seamless plastic jacket.
Examples of the more important features and advantages of this invention have thus been summarized rather broadly in order that the detailed description thereof that follows may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will also form the subject of the claims appended hereto. Other features of the present invention will become apparent with reference to the following detailed description of a presently preferred embodiment thereof in connection with the accompanying drawing, wherein like reference numerals have been applied to like elements, in which:
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a simplified side view showing the components of a tendon made by the present inventive method;
FIG. 2 is an enlarged simplified cross-sectional view taken on line 2--2 of FIG. 1;
FIG. 3 is a simplified diagrammatic view of the inventive method for making a tendon; and
FIG. 4 is a simplified front elevational view of a die used in the inventive method.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing, and in particular to FIGS. 1 and 2, the tendon made by the present inventive method is generally referred to by reference numeral 10. Tendon 10 comprises a multi-wire strand 11 composed of center wire 12 surrounded by six helically wrapped wires 14. The exposed or outer surface 16 of each of the six helically wrapped wires 14 is coated with a thin coat of thixotropic corrosion inhibitor 18. Of course, if and where the outer surfaces of adjacent wrapped wires 14 are in contact with each other, very little if any thixotropic corrosion inhibitor 18 may be present.
In the pockets 20 formed by the surfaces of adjacent wrapped wires 14 and the center wire 12 the amount of thixotropic corrosion inhibitor 18 may be greater than a thin coat in thickness since the thixotropic corrosion inhibitor 18 fills the volume so formed to describe pockets 20. The interstices 26 are not filled with thixotropic corrosion inhibitor since only the thin coats of thixotropic corrosion inhibitor 18 on wrapped wires 14 protrude into interstices 26. Thus the mess caused by excess amounts of grease in prior art tendons (which leaks out the ends of the tendons and through any breaks or pinholes in the jacket) is substantially eliminated by the present invention.
The thixotropic corrosion inhibitor 18 should have grease-like properties relative to its ability to be applied to the wrapped wires 14 and to stay put and adhere to the wires of the multi-wire strand 11. The thixotropic corrosion inhibitor not only acts as a corrosion inhibitor for the wires of the multi-wire strand 11 but also acts as a lubricant between the individual wires of the multi-wire strand 11 and between the multi-wire strand 11 and a loosely fitting seamless plastic jacket 22.
The coated wires 14 are surrounded by a loosely fitting seamless plastic jacket 22 which provides an air space 24 between the plastic jacket 22 and the outer surfaces 16 of the coated wrapped wires 14. The inside diameter of the seamless plastic jacket 22 is greater than the diameter of the multi-wire strand 11 such as to form a loosely fitting jacket. The diameter of the multi-wire strand 11 is the diameter of the circle that touches the outside surface of the wrapped wires 14.
The seamless plastic jacket 22 should be sufficiently thick and tough such as not to be easily punctured during shipping and handling and also during the positioning of the tendon and the pouring of the concrete therearound. The plastic used in making the jacket can be any thermoplastic polymer which has low permeability to air and moisture, high tensile strength and high stability in its chemical and physical properties. In the prsently preferred embodiment, the plastic used in either polyethylene or polypropylene of a thickness of up to twenty-five mils.
With reference to FIG. 3, the present inventive method for making a tendon is disclosed. In this method a multi-wire strand 11 is passed into pressure chamber 28 into which a corrosion inhibitor 18 is fed while under pressure through inlet 30. A guide and corrosion inhibitor retaining bushing 32 centers the multi-wire strand 11 and prevents the escape of the corrosion inhibitor 18. The pressure in the pressure chamber 28 is adjusted so that the corrosion inhibitor 18 penetrates and fills all the pockets 20 and coats the exposed or outer surfaces 16 of the helically wrapped wires 14 with a thick coating of the corrosion inhibitor 18. Bushing 32 reduces and smooths the corrosion inhibitor 18 around the multi-wire strand 11 so that the corrosion inhibitor 18 forms a circular encasement about the multi-wire strand 11 which has a diameter greater than the diameter of the multi-wire strand 11. The multi-wire strand 11, encased in the corrosion inhibitor 18, is then passed through die 34. Die 34 is mounted for rotational movement in casing 36 which is attached to pressure chamber 28. It will be appreciated that as the multi-wire strand 11 is pulled (without rotation) through opening 40 (see FIG. 4) of die 34, then die 34 must rotate to allow opening 40 to follow the path of travel of the six helically wrapped wires 14. Die 34 removes excess amount of the thick coating of the corrosion inhibitor 18 from the multiwire strand 11 such that only a thin coating of the corrosion inhibitor 18 remains on the outside surfaces of the multi-wire strand 11.
With reference to FIG. 4, the die 34 is disclosed and comprises a solid disc portion 38 with a centrally located opening or aperture 40 therein. The shape of the periphery of the opening or aperture 40 in die 34 conforms to and traces an exactness of the cross-sectional shape of the periphery of the multi-wire strand 11 used in making the tendon 10. The generally semi-circular cutouts or valleys 42 conform to the outer periphery of the wrapped wires 14 with the peaks or extensions 44 fitting into the interstices 26. The opening or aperture 40 is only slightly larger than the corresponding measurement of the multi-wire strand 11.
At this point in the inventive method for making a tendon the multi-wire strand 11 has been coated with a corrosion inhibitor 18 and the excess amount of corrosion inhibitor 18 has been removed such that only a thin coating of the corrosion inhibitor 18 remains. A loosely fitting plastic jacket 22 is now to be formed around the thinly coated multi-wire strand 11. A differential pressure may be created across the seamless plastic jacket 22 by introducing a quantity of gas, at a pressure greater than atmospheric, into the space between the coated multi-wire strand 11 and the seamless plastic jacket 22. A differential pressure may also be created across the seamless plastic jacket 22 by reducing the external pressure around the seamless plastic jacket 22 (e.g. by vacuum means) relative to the pressure residing in the space between the coated multi-wire strand 11 and the seamless plastic jacket.
In the embodiment in which the differential pressure is created by the introduction of a pressurized gas, the coated multi-wire strand 11 leaves casing 36 and enters air chamber 46 and then is passed through the throat 48 of tubing die 50. Compressed air is introduced into air chamber 46 through inlet 52 under a predetermined pressure of two to four p.s.i. Seal 54 provides a loose seal around the coated multi-wire strand 11 as the multi-wire strand 11 passes into air chamber 46 so as not to remove the corrosion inhibitor 18 therefrom but to control the leakage of air from air chamber 46 and to maintain a proper air pressure in air chamber 46. Simultaneously with the introduction of compressed air into air chamber 46, molten thermoplastic polymer 56 is extruded as a seamless plastic jacket 22 around the coated multi-wire strand 11. The compressed air enters chamber or pocket 58 through the throat 48 of tubing die 50 around the periphery of the multi-wire strand 11 and maintains the thermoplastic polymer 56 a predetermined distance from and greater than the diameter of the multi-wire strand 11 during initial cooling of the thermoplastic polymer 56, resulting in a loosely fitting seamless plastic jacket 22. It is preferable to adjust the rate of travel of the multi-wire strand 11 and the rate of extrusion of the thermoplastic polymer 56 so that there is a necking-down 60 of the thermoplastic polymer 56 at a distance from the tubing die 50 that will permit the cooling of the thermoplastic polymer 56 to a temperature below the vaporization temperature of the corrosion inhibitor 18 prior to completion of the necking-down process.
After the necking-down process it is preferable that the seamless plastic jacket 22 be rapidly cooled and hardened so that the tendon 10 may be wound onto a spool or otherwise handled for storage and/or shipment. Any method of cooling and any medium for cooling may be used as long as it is compatible with the seamless plastic jacket 22. In the method of FIG. 3 the multi-wire strand 11 and the loosely fitting seamless plastic jacket 22 are passed into a water cooling tank 62. Cold water enters the water cooling tank 62 through inlet 64 and exits outlet 66. Appropriate seals 68 through inlet 64 and exits outlet 66. Appropriate seals 68 at the entrance and exit points for tendon 10 minimize the leakage of water from the water cooling tank 62 and assist in maintaining the proper level of water in the water cooling tank 62 so that the water covers the tendon 10 and effectively cools the seamless plastic jacket 22 so that the seamless plastic jacket 22 hardens properly. Air is maintained in the space between the multi-wire strand 11 and the seamless plastic jacket 22 during the cooling and hardening process.
In the embodiment in which the differential pressure is created by reducing the external pressure around the seamless plastic jacket 22, a vacuum source is operatively connected to an enclosed cooling tank 62 so the exterior surface of the seamless plastic jacket 22 is subjected to a predetermined value of vacuum which results in a differential pressure across the wall of the the seamless plastic jacket 22 of about two to about four p.s.i. It will be appreciated that a special vacuum chamber could be provided just prior to the enclosed cooling tank 62 to provide the function of creating a differential pressure across the seamless plastic jacket.
The multi-wire strand 11 may be of any form and size. However, the multi-wire strands which are more commonly used are those having one straight center wire and six wires helically wrapped in one direction to cover the center wire. For post-tensioning of concrete, strands of about 0.30 inch to about 0.75 inch in diameter are normally used. It is preferable that the strands be of high-tensile steel which has a breaking strength of at least 200,000 p.s.i.
Although the present invention has been described in conjunction with specific forms thereof, it is evident that many alternatives, modifications and variations will become apparent to those skilled in the art in the light of the foregoing disclosure. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the manner of carrying out the invention. It is understood that the forms of the invention herewith shown and described are to be taken as the presently preferred embodiment. Various changes may be made in the shape, size and arrangement of parts. For example, equivalent elements may be substituted for those illustrated and described herein, parts may be reversed, and certain features of the invention may be utilized independently of other features of the invention. It will be appreciated that various modifications, alternatives, variations, etc., may be made without departing from the spirit and scope of the invention as defined in the appended claims.
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A method of making a tendon suitable for use in the post-tensioning of concrete as well as for other applications is disclosed. The method comprises the steps of coating a wire or a multiple-wire strand with a thin coat of a corrosion inhibitor. In the preferred embodiment, the thin coat may be more easily applied by coating the wire or multiple-wire strand with a thick coating of corrosion inhibitor and then removing the surplus amount of the corrosion inhibitor from the outer periphery of the strand, including the interstices, to leave the desired thin coat. A seamless plastic jacket is then formed around the wire or the multiple-wire strand while simultaneously creating a differential pressure across the wall of the seamless plastic jacket to provide a loosely fitting seamless plastic jacket.
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RELATED PATENTS
This application relates to U.S. Pat. No. 6,089,802 entitled “Cargo Restraint System for a Transport Container” issued on Jul. 18, 2000; U.S. Pat. No. 6,227,779 entitled “Cargo Restraint Method for a Transport Container” issued on May 8, 2001; U.S. Pat. No. 6,607,337 entitled “Cargo Restraint System” issued on Aug. 19, 2003; to U.S. Pat. No. 7,322,781 entitled “Adjustable Load Stabilizer Method and Apparatus” issued on Jan. 29, 2008 and application Ser. No. 11/459,356 filed Jul. 23, 2006 and entitled “Adjustable Load Stabilizer Method and Apparatus” all of common inventorship with the subject application. The disclosure of U.S. Pat. No. 7,322,781 and application Ser. No. 11/459,356 as both are referenced above, are hereby incorporated by reference as though set forth at length.
BACKGROUND OF THE INVENTION
This invention relates to an improved method and apparatus for stabilizing cargo during transportation. More particularly, this invention relates to a novel method and apparatus for stabilizing and restraining undesired movement of drums, boxes, rigid and flexible containers, palletized or not palletized, within the interior of a transport container or the like with respect to each other and/or with respect to the internal walls of the container.
Most shipments for transport are placed in enclosures such as ship cargo holds, intermodal containers, truck trailers, truck bodies, railroad box cars, and the like. Examples of cargo in containment enclosures include fifty five gallon closed head drums, super sacks or plastic reinforced bags, plastic wrapped bundles, cased goods, metal coils, specialty heavy paper rolls, plastic or metal containers mounted on pallets, etc. Although each individual component of cargo may be quite heavy and stationary at rest, the mass of a transport load can produce considerable momentum force as a ship, railroad car, truck trailer or truck body is placed in motion, stops, or changes direction.
During ocean shipping, cargo within cargo holds or intermodal containers are subjected to wave forces including: yaw, pitch, heave, sway, and surge. Depending upon weather conditions and the size of the vessel, cargo can experience various magnitudes of shifting forces throughout the course of a transoceanic voyage.
In another transport context, railroad trains are made-up by individual box cars being rolled together in a switching yard. When a railroad car is rolled into a stationary string of cars, the impact causes the car couplings to lock together with a jolt. This impact can apply a significant force to cargo within the rail car. Moreover, during transport, railroad cars and overland transport vehicles are subject to braking forces, bumps, centrifugal forces on curves, vibration, dips in the track or road, swaying, run-in or run-out forces, etc.
In overland truck/trailer transport there are frequent brake and acceleration forces imparted to the trailer and its contents, centrifugal forces around curves, turning forces, uneven road surfaces, roadway transition junctions, roadway grades, etc.
Each of these forces has the potential to impart a substantial force to cargo during transport. When cargo contacts other cargo or the interior walls or doors of a container, the force necessary to reduce its momentum to zero must be absorbed by the goods and/or the container. Such forces can result in damage to the cargo, damage to the interior walls or doors of the container, damage to the cargo packaging, and may even create dangerous leaks if the cargo is a hazardous material. Accordingly, it is undesirable to permit cargo to gain any momentum independent of other cargo or a transport container. This can be accomplished by stabilizing the cargo within the container with respect to other cargo and/or the internal walls of the container so that the cargo and container are essentially united and operationally function as a single object during transport.
In order to stabilize cargo with respect to other cargo and the internal walls of a transport container or cargo hold, various forms of load containments, load spacers and void fillers have been used to fill the spaces between cargo and between cargo and the internal walls of an intermodal container, box car, cargo hold, truck trailer, etc. Often, load containment enclosures are secured to the floor or sides of the transport container and prevented from moving with respect to each other by specially fabricated wood or steel framing, floor blocking, rubber mats, steel strapping, or heavy air bags. A variety of dunnage materials and void fillers has been used to prevent the movement of cargo with respect to other cargo and the internal walls of the transport container. Each of these previously known systems has limitations associated with cost, lack of strength, amount of labor required for installation, time expended for installation, lack of flexibility, securement integrity, transportability and storage of spacer elements, etc.
Further to the above, in the past, various dunnage materials have been utilized within transport containers to eliminate unwanted movement or shifting of a load. Drums, boxes, or other containers have been restrained in several different ways. Primarily, cargo has been stabilized by the use of void fillers such as collapsible cardboard frames or cells. These systems use strips of corrugated cardboard configured and assembled to expand into solid rectangular frames or cells of various forms and sizes and incorporate honeycomb and/or diamond-shaped cells for space and strength considerations. These systems while useful for known rectangular voids can exhibit impaired performance due to size and/or dimension variance. Moreover curved surfaces can not be accommodated well with rectangular shaped void fillers. The difficulty in applying various rectangular units to irregular shapes and the on site adjustment for varying sizes of voids to be filled, the unsuitability of corrugated board to absorb strong compression forces, and the use of materials not fully resistant to moisture can impair use of this type of dunnage void filler system.
Other known means of restraint such as the use of inflatable dunnage bags used alone or in combination with collapsible void fillers have tended to exhibit the disadvantage that air bags are subject to rupturing, leakage and loss of air pressure, or simply contraction and securement loosening in low temperature environments.
In addition to the above, other restraining systems known in the past often required additional elements and equipment which tended to be cumbersome to store, arduous to handle and/or install, and often required a degree of skilled labor in application.
Finally, in certain instances wood block and bracing has been used in the past to fill voids and secure loads; however, wood bracing is somewhat time consuming to install and often requires skilled or semi-skilled labor which is often contracted out to third parties. In addition certain wood materials are not suitable for international transport without fumigation which increases the overall cost of the securement system.
Consequently, a need exists for securing cargo in cargo holds, transport containers, box cars, truck trailers and the like that is functionally effective, cost-efficient, and labor-efficient. Still further a need exists for load stabilization systems that have enhanced strength characteristics under a variety of environments, exhibit flexibility for loads of various types and sizes and limit cargo shifting within a container.
The problems suggested in the preceding are not intended to be exhaustive but rather are among many which may tend to reduce the effectiveness of load stabilizer methods and apparatus appearing in the past. Other noteworthy problems may also exist; however, those presented above should be sufficient to demonstrate that load stabilizing systems appearing in the past will admit to worthwhile improvement.
SUMMARY OF THE INVENTION
One embodiment of the invention comprises a method and apparatus for stabilizing cargo within a ship hold, transport container, box car, truck trailer, and the like with respect to other cargo and the internal walls of the container by the selective application of mutually extendible void filler cylinders. More specifically, stabilization is achieved by application of extension members, which are capable of longitudinal movement with respect to each other. Each extension member is coupled to a bearing member which is designed to abut directly or indirectly against a face of cargo or an internal wall of a transport container. Securement is achieved by extending the extension members with respect to each other to fill in a void between the face of opposing cargo surfaces or an internal wall of a container, or the like. A locking mechanism is advantageously used to hold the extension members in place
THE DRAWINGS
Other aspects of the present invention will become apparent from the following detailed description of embodiments thereof taken in conjunction with the accompanying drawings wherein:
FIG. 1 is an axonometric view showing the interior of a railcard with cargo stabilized, both laterally and longitudinally, within the container in accordance with the subject invention;
FIG. 2 is an axonometric view showing the interior of a transport container secured to a flatbed of a truck or truck trailer, with cargo stabilized within the container in accordance with the subject invention;
FIG. 3 is a perspective view of one embodiment of the invention comprising a turnbuckle arrangement of extension members between bearing members;
FIG. 4 is a perspective view of one extension member used in the embodiment of the invention depicted in FIG. 3 ;
FIG. 5 is a cross-sectional view of the extension member as shown in FIG. 4 ;
FIG. 6 is a rotated cross-sectional view of the extension member like the one shown in FIG. 5 rotated by 90 degrees;
FIG. 7 is an end view of the extension member shown in FIG. 4 ;
FIG. 8 is a view of one side of the bearing member that is attached to one of the two extension members;
FIG. 9 is a side view of the bearing member shown in FIG. 8 ;
FIG. 10 is a view of an opposite side of the bearing member shown in FIG. 8 ;
FIG. 11 is a perspective view of a locknut used in one embodiment of the invention;
FIG. 12 is a cross-sectional side view of the locknut shown in FIG. 11 ;
FIG. 13 is a front view of the locknut shown in FIG. 11 ;
FIG. 14 is a back view of the locknut shown in FIG. 11 ;
FIG. 15 is a perspective view of the tubular members that may be used in an alternate preferred embodiment of the invention;
FIG. 16 is a plan view of a bearing member that is employed in the embodiment of the invention shown in FIG. 15 ; and
FIG. 17 , note again sheet two, is a perspective view of yet another embodiment of the subject load stabilizer invention.
DETAILED DESCRIPTION
Context of the Invention
Turning now to the drawing wherein like numerals indicate like parts, FIG. 1 shows an axonometric view of an operating environment 100 of the invention. In this, a railcar 102 is shown as a type of container that may be encountered. Railcars are used to transport a wide range of materials including many that must be protected from impact against the railcar walls as well as other cargo within the railcar. Cargo 104 must be protected from the shifting forces during transit. One particular force encountered in railcars specifically is the impact force created when two railcars are cased to collide in order to connect a coupling 106 . The form of container 102 shown here is merely illustrative and the subject invention can be also used to advantage in ship cargo holds, intermodal containers and the like.
A partially cut away portion of FIG. 1 depicts various size and shapes of cargo 104 , which are stabilized against each other and against the internal walls of the container 102 by load stabilizers 108 in both a lateral and longitudinal direction in accordance with the subject invention.
FIG. 2 shows another operational context 200 of the invention. In this context, container 204 is secured to a trailer towed by tractor 202 . Cargo 206 is subject to a wide range of forces as discussed above. The braces or load stabilizers 208 of the subject invention protect the cargo from shifting and impact with other cargo and with the walls of the container 204 .
Void Filler and Load Stabilizer
Turning now to FIG. 3 there is shown one preferred embodiment of the present invention. In this, a void filler 300 employs a turnbuckle configuration to extend and retract the bearing members. Male tubular members 302 are threaded to correspond to the internal threading of female member 304 . When the female member 304 is turned with respect to the male members 302 , this causes the bearing members 306 to either mutually extend or retract. The female member 304 may be turned by hand or with a tightening tool just as a lock-belt wrench. Male and female tubular members attach to the bearing members 306 by a base sliding into channels and locking at 308 . Contours 310 are placed in bearing members 306 through the injection molding process and allow the bearing members to be extracted from the mold. This is not a requirement for the function of the invention.
This configuration is particularly useful because it allows the void filler to expand to fit relatively large spaces. The female member 304 may be reverse threaded for use as described above, or it may be a single threaded female member where only one male member is turned to extend to the container wall or to ether cargo. Locknuts 312 are tightened against female member 304 to secure the male members in place and prevent slippage.
The void filler 300 can be configured to always remain assembled or it can be configured to be broken down into its separate components. When the disassembled embodiment is used, then this invention provides the additional benefit of being easy to ship to its destination. For example, drop-down type cardboard void fillers can be shipped at approximately 100 pieces per pallet. The subject invention can be shipped at between 900 and 1000 pieces per pallet. This is due to its configuration and the ability to stack the base elements and closely pack the tubular members.
FIG. 4 is a perspective view of a male tubular member 400 such as element 302 of FIG. 3 . Threads 402 extend along the body of the tubular member and correspond to threads in a female tubular member such as element 304 . In one embodiment, both tubular members are double threaded or even triple threaded so that two or three threads are used simultaneously. In another embodiment, these threads are set with a pitch, that cooperates with the coefficient of friction of the unit and weight of the unit that allows the tubular members to be self driving when the void filler is assembled and a turning force is applied. Lip 406 slides into place on a bearing member such as 306 . The slots of the bearing member fit in space 408 and lip 404 rests on top of the bearing member slots for additional stability. Additional security is b e provided by a small ramp that holds the tubular member in place and prevents sliding out of the slot on the bearing member.
FIG. 5 shows a cross-sectional view of a male tubular member 500 such as the one designated as element 302 in FIG. 3 . Threads 502 correspond to the internal threads of a female tubular member. Lip 506 fits into slots on a bearing member as described above and lip 504 rests on the slots on a bearing member for stability as described above.
FIG. 6 shows a view of the same member shown in FIG. 5 but rotated 90°. This view of a male tubular member 600 shows threads 602 as well as lips 604 and 606 . The slots on the bearing member fit into spaces 608 . This view shows that the lip 606 has flat sides to allow for fitting into the bearing member as described above.
FIG. 7 shows an end view of a male tubular member 700 . Threads 702 fit into a female tubular member and lips 704 and 706 fit into a bearing member as described above.
FIG. 8 is a detailed plan view of the bearing member 800 with the side shown facing in toward the tubular members shown in FIG. 3 , Tubular members, such as 302 and 304 , attach to the bearing member 800 by base elements at the adjacent ends of the tubular members in position 802 of the bearing members. The tubular member is placed over ramp 804 , then it can be slid down into position 802 by ensuring that the edge of the tubular member, to be detailed below, fits under slot 808 on each side. Once in position, ramp 804 ensures that the tubular member will not inadvertently slide out of its attachment with the base. Dimple 806 is slightly raised and gives additional security to the attachment of the tubular member.
For added strength, the bearing member 800 is reinforced. Reinforcement spines 810 and 812 provide circumferential reinforcement by being placed around the outside of the base as well as in a position between the outside of the base and the center of the base, as 812 . There is no limit to the number of rings that may be used, the more rings, the greater the ability of the base to withstand outside stresses. Additionally, reinforcement spines 814 provide radial reinforcement. Again, there can be any number of reinforcement elements depending on the desired strength. Elements 810 , 812 and 814 are made of the same material as the remainder of the base but are thicker and provide greater support. Nail, screw or other attachment holes 816 allow the base to be secured to any surface. These may be actual holes, or they may be portions of the base that are thin with respect to the rest of the base and allow nails, and the like, to be easily driven through.
The subject invention may be constructed of a wide range of materials. In one embodiment, the tubular members are constructed of high density polyethylene and the bases are constructed of acrylonitrile butadiene styrene (ABS.) The subject invention can be constructed of any one, or any combination of the following materials: polyvinyl chloride (PVC), ABS, polyethylene, and polystyrene. This lists is not meant to be exhaustive, any material that provides the requisite strength and reliability for protecting cargo may be used to advantage.
FIG. 9 shows a side view of a base 900 such as the one shown in FIG. 8 . Tubular members such as 302 and 304 fit in slot 906 and are held in place by ramp 910 . Dimple 908 also helps to hold the tubular member securely in place. The tubular members are released by slightly bending the base to slide the tubular member over ramp 910 . Nail hole 904 is shown extending only partially through base 900 . A nail can be driven through this and into a surface. Optional adhesive element 912 allows the base to be adhered to a container wall or opposing cargo so it can be easily positioned and the void guard assembled by one person. Typically, this adhesive will be on a base attached to a male tubular member so the female member is free to turn into position. With the turnbuckle embodiment the adhesive may be provided on the outside surface of each of the load bearing members.
FIG. 10 shows an opposite side of a bearing member 1000 such as the one shown in FIG. 8 . Surface 1002 is smooth and contacts either the container wall or a surface of cargo in the container. Dimple 1004 and holes 1006 are products of the injection molding process and are not required for the function of the void filler although dimple 1004 does provide extra security for the inserted tubular member on the opposite side as described above. The primary requirement for this surface is that is not have protrusions extending out that would damage the cargo. However, in another embodiment, the user may require a mechanical connection with the cargo and damage is not an issue; in this case, protrusion off the base could be used to secure the base to the surface. Optional adhesive element 1008 allows the base to be removeably affixed to either a cargo surface or a container wall.
FIG. 11 is a perspective view of a locknut 1100 such as the one labeled 312 in FIG. 3 . Threads 1102 correspond to the threads of a male tubular member, such as element 302 . Contours 1104 allow the locknut to turned into place by hand and may take a variety of forms. The locknut may also be shaped to correspond to a turning tool and tightened into place with that tool.
FIG. 12 is a cross sectional view of the same locknut, labeled 1200 . Threads 1202 and contours 1204 correspond to those described above regarding FIG. 11 .
FIG. 13 is another view of the locknut 1300 such as the one illustrated in FIGS. 11 and 12 . Threads 1302 and contours 1304 correspond to those described above regarding FIG. 11 .
FIG. 14 is an opposite end view of a locknut 1400 such as the one shown in previous FIGS. 11-13 . Threads 1402 and contours 1404 correspond to those described above regarding FIG. 11 . Note reinforcing spines radiating out to provide additional stability and strength for the locknut 1400 .
FIG. 15 is a perspective view of an alternative embodiment 1500 of the invention including tubular members that may be used in conjunction with a bearing member. Male tubular member 1502 , female tubular member 1504 , and snap on ends 1506 cooperate with bearing members 1600 as shown in FIG. 16 . In this embodiment, the tubular members attach to the bearing members 1600 by inserting hooks 1512 into holes 1606 (see below). The device may be made of any material suitable to allow these hooks to flex adequately to fit into position and hold the base secure. Round member 1510 may be raised slightly (no more than the thickness of the base) and insert into hole 1604 of the bearing member.
FIG. 16 shows an alternative embodiment of a bearing member 1600 that may be used to advantage in the subject invention. Spines 1608 extend radially to the edge 1602 of the bearing member 1600 . The tubular members connect by snapping in with hooks at connection ports 1606 . Optional hole 1604 may correspond to a round stabilizing member on connected tubular member and increase the stability of the connection. Nail holes 1610 may be used to secure the bearing member to an appropriate surface. Adhesive may also be used as described above.
FIG. 17 , note again sheet two of the drawings, shows yet another embodiment of the present invention. Void filler 1700 employs a pin-lock mechanism for extending, retracting, and holding in place the tubular members. As shown, the tubular members may be square or triangular in cross section alternatively, they may be round, oval or any other appropriate shape that allows for telescoping with respect to one another. In this embodiment, male tubular member 1702 slides into female member 1704 . The holes in 1702 and 1704 are lined up and a pin 1706 is placed through the holes to hold the members in place. Bearing members 1708 , holes 1712 , and slots 1714 correspond to the similar elements described above with regard to the void filler. In addition there may be a single hole in one of the male and female members and multiple holes in the other member. In addition the holes may be finely spaced longitudinally the next closest hole longitudinally being positioned on an alternative lateral surface so that next adjacent holes longitudinally do not intersect on the same surface of extension member.
Note that although particular extension mechanisms have been described, any suitable extension method and/or apparatus would be acceptable. This may include a ratchet mechanism where the tubular members are easily extended, but cannot move back the opposite direction, or a friction based system where the tubular members are extended and held by locking them and relying on friction to hold them in place.
The subject invention also includes methods of operation to fill voids within a transport container. There is no particular order implied in the steps of the method and they can be performed in any suitable order. In one embodiment, the bearing member attached to a male tubular member is placed flush with a piece of cargo or another surface in the transport container. While this is held in place, the female tubular member with attached base is turned in relation to the male tubular member. This extends the female tubular member toward another surface or cargo in the transport container. The female tubular member is turned until the second bearing member is in contact with the opposing surface and tightened sufficiently. A locknut on the male member is then turned into position to secure the void filler at the desired length.
This method is not exhaustive and can be practiced on any of the embodiment described above. The void filler will be extended using the selected extension mechanism and held in place.
The preceding description has been presented only to illustrate and describe the invention and some examples of its implementation. It is not intended to be exhaustive or to limit the invention to any precise form disclosed. Many modifications and variations are possible and would be envisioned by one of ordinary skill in the art in light of the above teaching.
The various aspects were chosen and described in order to best explain principles of the invention and its practical applications. The preceding description is intended to enable others skilled in the art to best utilize the invention in various embodiments and aspects and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims; however, it is not intended that any order be presumed by the sequence of steps recited in the method claims unless a specific order is directly recited.
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A method and apparatus for stabilizing cargo within a transport container is presented. First and second tubular elements are provided having generally cylindrical bodies and bases at a terminal end which can react against opposing surfaces within the transport container and stabilize cargo within the container. An extension mechanism allows for the extension and selective translation between the first and second tubular members allowing the apparatus to extend and fill the space between opposing surfaces within the transport container and stabilize the cargo. A method for stabilizing cargo within a transport container includes providing an extensible load stabilizer having first and second tubular elements, each having a base, positioning the load stabilizer between opposing surfaces within the transport container, and extending the tubular members with respect to each other, and stabilizing a surface of cargo against an opposing surface.
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BACKGROUND OF THE INVENTION
[0001] The invention relates to devices for pumping of fluids, and may be used in the industry, transport and households at pumping of liquids, other incompressible and compressible fluids, and at producing of oil from wells.
[0002] The closest analogue of the claimed technical solution is a piezoelectric pump unit for pumping fluids described in the patent RU2452872, published Jun. 10, 2012, Int'l Class 8 F04B 9/00. The pump comprises a housing, piezo anchor, located in the housing and a displacer, located in the front part of the housing. The piezo anchor and the displacer are connected. The piezo anchor consists of a rear piezoelectric clamp section, a piezoelectric extender section that is movable relative to the housing in the direction of changing its length, and a front piezoelectric clamp section, connected in series. The piezoelectric clamp sections and the piezoelectric extender section are made with material capable to change its length at connecting an electric potential to it, for example of piezoceramic material.
[0003] Electrical pulses coming to the piezoelectric clamp sections cause them to lock in the housing one-by-one. The piezoelectric extender section provides periodical movement of the clamp section that is not fixed in the housing at one step under influence of an electrical pulse coming to it. This causes a step-by-step movement of the displacer relative to the housing in one direction.
[0004] Pumping unit supply largely depends on the length of the piezoelectric extender section. However, the considerable length of that section it not only increases in length due to incoming electrical pulses, but may also bend. This is a so-called loss of stability under longitudinal compression. When excluding the loss of stability of a long piezoelectric extender section, it is possible to increase the supply of piezoelectric pump unit significantly.
SUMMARY OF THE INVENTION
[0005] The problem to be solved by the present technical solution is to extend the limits of applicability of the piezoelectric pump unit.
[0006] The technical result achieved by implementing the invention is to increase the supply of the piezoelectric pump unit.
[0007] For solution of the problem with achievement of the technical result in the known piezoelectric pump unit, consisting of a housing, a piezo anchor, located in the housing, a displacer, located in the front of the housing, the piezo anchor and the displacer are connected, the piezo anchor consists of a rear piezoelectric clamp section, a piezoelectric extender section that is movable relative to the housing in the direction of variation of the piezoelectric extender section length, and a front piezoelectric clamp section, connected in series; according to the invention claimed at least one slider introduced in the piezoelectric extender section between its front and rear ends, the slider contacts the housing from inside.
[0008] Due to the new design of the piezoelectric extender section and an additional connection between it and the housing it is possible to increase the supply of piezoelectric pump unit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The abovementioned advantages of the invention and its features are explained in the preferred embodiment with reference to the drawings.
[0010] FIG. 1 shows a piezoelectric pump unit with a longitudinal cut view of the housing;
[0011] FIG. 2 —cross-sectional cut view of the piezoelectric pump unit at the rear piezoelectric clamp section region (wires not shown);
[0012] FIG. 3 —cross-sectional cut view of the piezoelectric pump unit at the piezoelectric extender section region (wires not shown);
[0013] FIG. 4 —longitudinal cut view of the extender section;
[0014] FIG. 5 —cross-sectional cut view of the piezoelectric pump unit at the front piezoelectric clamp section region (wires not shown).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] The piezoelectric pump unit ( FIGS. 1 and 4 ) comprises a hollow housing 1 and a piezo anchor 2 disposed therein. The piezo anchor 2 consists of a rear piezoelectric clamp section 3 , a piezoelectric extender section 4 and a front piezoelectric clamp section 5 , connected in series. The rear piezoelectric clamp section 3 consists of a bracket 6 and piezo stacks 7 and 8 . The bracket 6 is a U-shaped part composed of two longitudinal bars and a transverse bar connecting them. Piezo stacks 7 and 8 are disposed between the longitudinal bars of the bracket 6 ( FIG. 1 , 2 ). The direction of the piezo stacks 7 and 8 length variation at coming voltage to them is perpendicular to the longitudinal bars of the bracket 6 .
[0016] The front piezoelectric clamp section 5 consists of a bracket 9 and piezo stacks 10 and 11 . The bracket 9 is a U-shaped part composed of two longitudinal bars and a transverse bar connecting them. Piezo stacks 10 and 11 are disposed between the longitudinal bars of the bracket 9 ( FIG. 1 , 2 ). The direction of the piezo stacks 10 and 11 length variation at coming voltage to them is perpendicular to the longitudinal bars of the bracket 9 .
[0017] The transverse bar of the U-shaped bracket 6 of the rear piezoelectric clamp section 3 faces forward, and the transverse bar of the U-shaped bracket 9 of the front piezoelectric clamp section 5 faces backward.
[0018] The rear end of the piezoelectric extender section 4 is connected to the transverse bar of the U-shaped bracket 6 of the rear piezoelectric clamp section 3 and its front end connected to the transverse bar of the U-shaped front bracket 9 of the front piezoelectric clamp section 5 . All the longitudinal bars of the U-shaped brackets 6 and 9 are parallel.
[0019] Depending on the required pump unit pressure the required number of the piezo stacks in the piezoelectric clamp sections 3 and 5 is comprised in the pump unit.
[0020] In the piezoelectric extender section 4 the slider 12 is provided ( FIGS. 1 , 4 ) between its front and rear ends that contacts the housing from inside. For the long piezoelectric extender section 4 there may be few sliders evenly distributed along the section. Contacting the inner walls of the housing 1 under compressive loads, the sliders do not allow the piezoelectric section 4 to bend.
[0021] The pump housing 1 may be partially or completely filled with the liquid polyethylsiloxane. For flowing of liquid while piezo anchor 2 is moving the holes 13 in the slider 12 ( FIG. 4 ) are provided thus connecting the internal housing space from back of the slider with the internal space in front of the slider.
[0022] There is a piezo stack 14 ( FIGS. 1 , 3 ) between the front end of the piezoelectric extender section 3 and the slider 12 . The piezo stack 15 ( FIG. 1 ) is provided between the slider 12 and the rear end of the piezoelectric extender section. The piezo stacks may be provided between the sliders (for a construction with few slides) also.
[0023] There is a rod 16 ( FIGS. 3 , 4 ) in the piezoelectric extender section. It extends from the rear end of the piezoelectric extender section 4 ( FIG. 1 ) to its front end. The transverse bar of the U-shaped bracket 6 ( FIG. 4 ) of the rear piezoelectric clamp section 3 and the rod 16 are connected with a threaded connection. The transverse bar of the U-shaped bracket 9 ( FIG. 1 ) of the front piezoelectric clamp section 5 and the rod 16 are connected with a threaded connection. Direction of the piezo stack 14 and 15 length variation at coming an electric voltage to them coincides with the direction of the rod 16 .
[0024] There is a foramen 17 inside the piezoelectric extender section 4 ( FIGS. 3 , 4 ) that connects the internal space of the housing near the rear end of the piezoelectric extender section with an internal space of the housing near the front end of the piezoelectric extender section, intended for additional cooling of the piezo stacks 14 and 15 , as well as for possible flow of liquid through the piezoelectric extender section 4 ( FIGS. 3 , 4 ). There is a clearance between the piezoelectric extender section 4 and the rod 16 disposed inside it. The foramen 17 is formed by a clearance between the rod 16 and the piezoelectric extender section 4 . In the piezoelectric extender section 4 near its rear end there is a hole 18 connecting the foramen 17 with the internal space of the housing. Also in the rear piezoelectric clamp section 3 in the bracket 6 holes 19 are provided connecting the foramen 17 with the internal space of the housing. In the piezoelectric extender section 4 near its front end there is a hole, connecting the foramen 17 with the internal space of the housing. Also in the front piezoelectric clamp section 5 in the bracket 9 holes 19 are provided connecting the foramen 17 with the internal space of the housing.
[0025] The housing 1 of the pumping unit consists of two friction plates 20 ( FIGS. 2 , 3 and 5 ) and the two cheeks 21 . The friction plates 20 are arranged parallel, one plate is opposite another plate. The cheeks 21 are attached between them forming an internal space, the front opening of the internal space and the rear opening of the internal space. The piezo anchor 2 ( FIG. 1 ) locates in the internal space. The longitudinal bars of the U-shaped brackets 6 and 9 of the rear and front piezoelectric clamp sections 3 and 5 , respectively, contact the friction plates 20 from inside. The displacer housing 22 is a part of the housing 1 . The displacer housing 22 is connected to the front opening of the internal space. In the absence of liquid in the housing 1 or at partial filling of it by liquid the rear opening of the housing can be hermetically closed by a cover.
[0026] The seal section 23 ( FIG. 1 ) isolates the internal space of the housing 1 , wherein the piezoelectric sections 3 , 4 and 5 move, from the pumped medium.
[0027] The seal section is made of a liquid impermeable thin material having a peripheral edge and a hole. The seal section peripheral edge sealingly fixed in the front part of the housing 1 around its internal space opening. The displacer 24 locates in the hole of the seal section. The edge of the seal section hole is sealingly fixed around the displacer 24 , sealing the front internal space of the housing where the piezoelectric sections are. The through openings 25 are provided in the housing 1 between the fixing place of the seal section peripheral edge and the contact area of the displacer 24 with the housing 1 .
[0028] The seal section may be made as a flexible membrane or a diaphragm or a bellows tube. The bellows tube as a seal section can be of a membrane type 26 ( FIG. 1 ) or with rounded vertices and depressions on its cross-section. At least one slider 27 of a ring shape between the front and rear ends of the seal section 23 is provided additionally. The slider 27 is coaxially and sealingly connected to the seal section 23 , more exactly to its bellows tubes. The slider 27 contacts the displacer 24 .
[0029] As a displacer 24 the piston 28 may be used connected to the piezo anchor 2 (in the design shown in FIG. 1 it is connected to the bracket 9 ). The seal section may be performed as a gland seal, hermetically fixed to the housing 1 in the region between the front piezoelectric clamp section 5 and piston 28 . The rear portion of the piston may slide in the gland seal.
[0030] An opening may be provided in the housing 1 that connects an outer surface of the housing and the internal space of the housing, where the piezoelectric sections are. At that a compensator is introduced into the design of the unit made of a liquid impermeable thin material. The peripheral edge of the compensator is sealed around the opening of the housing 1 to seal the interior of the housing, where the piezoelectric sections 3 , 4 and 5 are. The housing 1 is partially or completely filled with liquid in that design.
[0031] A compensator 29 is provided additionally in the pump unit design shown in FIG. 1 . It is made of a liquid impermeable thin material such as stainless steel or brass. The peripheral edge of the compensator is sealed around the rear opening of the internal space of the housing. The housing is partially or completely filled with liquid at that such as liquid polyethylsiloxane. The compensator may be a flexible membrane or a diaphragm or a bellows tube.
[0032] The bellows tube may be used of a type with rounded vertices and depressions on its cross-section or of a membrane type, as it is shown in the compensator 29 in the FIG. 1 . The unattached edge of the bellows tube compensator is hermetically attached to the cover 30 . The cover 30 contacts the housing 1 from inside. There is an opening 31 in the peripheral portion of the cover 30 . The opening 31 connects the outer surface of the compensator bellows tube with the outer space.
[0033] A slider 32 between the front and rear ends of the compensator 29 is provided additionally, it is of a ring shape. The slider 32 is coaxially and sealingly connected to the compensator 29 , to its bellows tubes. The slider 32 contacts the housing 1 from inside. In the peripheral portion of the slider ring 32 there is an opening 33 , connecting the outer surface of compensator bellows tube in front of the slider 32 with the outer surface of the bellows tube of the compensator 32 in the back of the slider.
[0034] Parts assembling of the housing 1 is done by bolts 34 ( FIGS. 2 , 3 , 5 ) or by threaded studs. They may be sealed with seal rings and/or welding by tin, tin solder, silver solder, copper-phosphorus brazing, brass.
[0035] To provide the cyclic operation of the pump unit an intake valve 35 and an exhaust valve 36 are provided. The valves are located in the front part of the housing 1 before the displacer 24 .
[0036] The displacer 24 (or the piston 28 ) is connected to the piezo anchor 2 . In the design shown in the FIG. 1 it is connected to the front end of the piezoelectric extender section 4 (the bracket 9 ) by means of the elastic member 37 . The elastic member 37 reduces vibrations generated during the linear movement of the piezo anchor 2 and transmitted to the displacer 24 . The elastic member 37 is made of material ensuring acceptable damping of vibrations due to its elasticity and damping properties. The elastic member 37 may be designed as a spring, such as a leaf spring. It is possible to perform the design in the form of a helical spring or in the form of a rocker made of elastic and/or damping material.
[0037] An electric wire 38 is connected to the piezo stacks 7 and 8 of the rear piezoelectric clamp section 3 . An electrical wire 39 is connected to the piezoelectric extender section 4 . An electric wire 40 is connected to the piezo stacks 10 and 11 of the front piezoelectric clamp section 5 . The electric wires 38 , 39 and 40 are connected to the electrical connector 41 . The electrical connector 41 may be placed in the housing, providing connection of an electrical power cable from outside of the unit.
[0038] The power cable connected from the outside of the unit may be performed with four wires: three power wires and a common wire. Also the power cable may be configured as a shielded three-wire cable, each wire should have its independent shield in this case. Also, there may be additional wires in the cable for feedback sensors and telemetry devices.
[0039] In the first phase of discharge the rear piezoelectric clamp section 3 is in the clamped state. That means that the U-shaped bracket 6 is pressing onto the housing 1 from inside in the transverse direction. It takes place due to coming of an electric voltage from the electric connector 41 through the wire 38 to piezo stacks 7 and 8 . The front piezoelectric clamp section 5 in this phase of discharge is in a free state, the clamping effort is minimal or is absent at all between the bracket 9 and the plates of the housing 1 . At the same time there is no gap. A gap means the incorrect settings, fault, excessive temperature or wear of the pump unit. Presence of the gap cause additional vibration, lowering of pressure and possible closest failure of the unit.
[0040] In the second phase of discharge an electrical voltage comes through the wire 39 to the piezoelectric extender section 4 , and the section increases its length. The front clamp section 5 connected to it moves forward at a short distance against the force of the compression rod 16 .
[0041] In the third phase of discharge an electrical voltage from the wire 40 comes to the front piezoelectric clamp section 5 , to its piezo stacks 10 and 11 , and the bracket 9 begins to press from inside on the housing 1 . In other words, the section 5 turns into the clamped state. At the same time an electric voltage from the wire 38 does not come to the rear piezoelectric clamp section 3 , and it turns into the free state, not pressing from inside on the housing 1 , or pressing with the least possible force. However the gap between the housing and the bracket 9 is also missing in this case.
[0042] In the fourth phase of discharge an electrical voltage does not come any more through the wire 39 to the piezoelectric extender section 4 . The section 4 turns into the free state, that is, its length is decreased. The rear piezoelectric clamp section 3 moves forwardly for a short distance from the force of the compression rod 16 at that phase. At the end of the fourth discharge phase an electric voltage does not come to the front piezoelectric clamp section 5 from the wire 40 , and it turns to the free state, that means it does not press from inside on the housing 1 any more.
[0043] Such a phases rotation provides stepping displacement of piezoelectric sections 3 , 4 and 5 forwardly. Since the displacer 24 (piston 28 ) is connected with the moving piezo anchor 2 by an elastic element 37 , then filling liquid from space between the piston 28 and the housing of the piston 22 moves with it forwardly. The intake valve 35 is closed and the outlet valve 36 is opened. Fluid flows out of the piezoelectric pump unit with pressure through it.
[0044] The phases sequence is repeated at discharge many times until the the fluid displacer 24 (piston 28 ) reaches its extreme front position. The moment when the extreme front position is reached is determined from curve of the electric current changing in the wire 39 . Also this moment can be monitored by means of piezoelectric sections position feedback sensor or a displacer position feedback sensor.
[0045] Sucking starts after the displacer of the working fluid 24 (piston 28 ) reaches its extreme front position. In the first phase of suction the rear piezoelectric clamp section 3 of the piezoelectric pump 1 is in a free state, that is, the U-shaped bracket 6 does not press on the housing 1 from inside, or it presses with a minimal effort.
[0046] In the second phase of suction the piezoelectric extender section 4 increases its length. The rear clamp section 3 is moved backward at a short distance overcoming force of the compression rod 16 .
[0047] In the third phase of suction the front piezoelectric clamp section 5 turns to its free state. At the same time the rear piezoelectric clamp section 3 turns into the clamped state starting to press on the housing 1 from inside.
[0048] In the fourth phase of the suction the piezoelectric extender section 4 under force of the compressing rod 16 turns into the free state, that is, reduces its length. The front piezoelectric clamp section 5 moves backward for a short distance.
[0049] Such a phases sequence is repeated at suction many times until the fluid displacer 24 (piston 28 ) reaches its extreme rear position. The moment when the extreme rear position is reached is determined from curve of the electric current changing in the wire 39 . Also this moment can be monitored by means of piezoelectric sections position feedback sensor or a displacer position feedback sensor (not shown in the drawings).
[0050] As the piston 28 is connected to the moving piezo anchor 2 , pumped fluid is sucked in due to movement of the piston 28 , filling the space between the piston 28 and the housing of the displacer 22 . The intake valve 35 is opened and the outlet valve 36 is closed.
[0051] The elastic member 37 due to its elasticity and damping properties reduces vibration waves generated at movement of the piezo anchor 2 and transmitted to the piston 28 . It decreases possibility of pumped fluid cavitation, as well as longitudinal vibration of the unit.
[0052] The claimed piezoelectric pump unit is industrially applicable in transport and industry for pumping fluids of high pressure and relatively low supply in the most successful way, where usage of other types of pumps is hardly possible due to dimensions, weight and effectiveness.
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The piezoelectric pump unit consists of a housing, a piezo anchor, located in the housing, a displacer, located at the front of the housing. The piezo anchor and the displacer are connected. The piezo anchor consists of a rear piezoelectric clamp section, of a piezoelectric extender section and of a front piezoelectric clamp section, connected in series. At least one slider is introduced in the piezoelectric extender section between its front and rear ends. Electric pulses accessing at sections from a control station cause said sections to become fixed alternately inside the housing. Under the effect of electric pulses, the piezoelectric extender section moves the displacer step-by-step in one direction.
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RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/655,732 filed Jun. 5, 2012, incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to an integrated process for treating whole crude oil to remove asphalt and other impurities therefrom. To elaborate, the integrated process comprises the steps of separating asphalt from the whole crude oil, followed by treating the deasphalted oil via hydrotreatment/hydrocracking with a catalyst, to remove materials such as sulfur and nitrogen. In parallel, the recovered, asphalt containing fraction can be gasified, to produce hydrogen that is then used in the hydrocracking step.
BACKGROUND AND PRIOR ART
[0003] Conventional processes for treating crude oil involve distillation, and then various cracking, solvent refining, and hydroconversion processes, so as to produce a desired group of products, such as fuels, lubricating oil products, petro-chemicals, chemical feedstocks, and the like. An exemplary process includes the distillation of the crude oil in an appropriate atmospheric distillation column, resulting in gas oil, naphtha, other gases, and atmospheric residuum. This last portion is fractionated further in a vacuum distillation column, so as to produce so-called vacuum gas oil, and vacuum residuum. The vacuum gas oil, in turn, is usually cracked via fluid catalytic cracking or hydrocracking, to produce more valuable light transportation fuel products, while the residuum can be processed further, to yield additional useful products. The methods involved in these processes can include, e.g., hydrotreating or fluid catalytic cracking of the residuum, coking, and solvent deasphalting. Any materials recovered from crude distillation at fuel boiling points have typically been used, directly, as fuels.
[0004] To elaborate on the processes described, supra, solvent deasphalting is a physical, separation process, where feed components are recovered in their original states, i.e., they do not undergo chemical reactions. Generally, a paraffinic solvent, containing 3-8 carbon molecules, is used to separate the components of the heavy crude oil fractions. It is a flexible process, which essentially separates atmospheric, and vacuum heavy residues, typically into two products: (i) asphalt and (ii) deasphalted or demetallized oil, referred to as “DAO” or “DMO,” respectively hereafter. The choice of solvent is left to the skilled artisan, and is chosen with desired products, yields, and quantities in mind, as are other process parameters, such as the operating temperature, and the solvent/oil ratio. As a general rule, as the molecular weight of the solvent increases, so does solubility of the oil into the solvent. For example, either propane or a propane/isobutane mixture is typically used to manufacture lube oil bright stock. If, on the other hand, the DAO will be used in conversion practices, like fluid catalytic cracking, solvents with higher molecular weights (e.g., butane or pentane, or mixtures thereof), are used. The products of DAO solvation include those described supra, as well as lube hydrocracking feed, fuels, hydrocracker feed, fluid catalytic cracking feed, or fuel oil blends. The asphalt product may be used as a blending component for various grades of asphalt, as a fuel oil blending component, or as a feedstock for heavy oil conversion units (e.g., cokers.)
[0005] Conventional solvent deasphalting methods are carried out without catalysts or adsorbents. U.S. Pat. No. 7,566,394, the disclosure of which is incorporated by reference, teaches improved solvent deasphalting methods which employ solid adsorbents. The improvement in the methodology leads to separation of nitrogen and polynuclear aromatics from DAO. The adsorbents are then removed with the asphalt products, and are either sent to an asphalt pool, or gasified in a membrane wall gasifier, where solids are required.
[0006] Hydrocracking processes, as is well known, are used commercially in many refineries. A typical application of a hydrocracking process involves processing feedstreams which boil at 370° C. to 520° C. in conventional units, and those which boil at 520° C. and above, in so-called “residue units.” Simply stated, hydrocracking is a process by which C—C bonds of large molecules in a feedstream, are broken, to form smaller molecules, which have higher volatility and economic value. In addition, hydrocracking processes typically improve the quality of hydrocarbon feedstock, by increasing the H/C ratio by hydrogenation of aromatic compounds, and by removing organo-sulfur, and organic nitrogen compounds.
[0007] Given the significant economic benefits that result from hydrocracking, it is not surprising that there have been substantial developments in improving hydrocracking processes, and the development of more active catalysts.
[0008] In practice, hydrocracking units usually include two principal zones: a reaction zone and a separation zone. There are also three standard configurations: single stage, series-flow “once-through”), with and without recycling, and two stage processes, with recycling. The choice of reaction zone configuration depends upon various parameters, such as feedstock quality, the product specification and processing objectives, and catalyst selection.
[0009] Single stage, once-through hydrocracking processes are carried out at operating conditions which are more severe than typical hydrotreating processes, but which are less severe than conventional full pressure hydrocracking processes. Mild hydrocracking is more cost effective than more severe processes but, generally, it results in production of lesser amounts of desired middle distillate products, which are of lower quality than the products of conventional hydrocracking.
[0010] Single or multiple catalyst systems can be used depending upon, e.g., the feedstock processed and product specifications. Single stage hydrocracking units are generally the simplest configuration, designed to maximize middle distillate yield over a single or dual catalyst system. Dual catalyst systems are used in stacked-bed configurations or in two different reactors.
[0011] Feedstock is typically refined over one or more amorphous-based hydrotreating catalysts, either in the first catalytic zone in a single reactor, or in the first reactor of a two-reactor system. The effluents of the first stage are then passed to the second catalyst system which consists of an amorphous-based catalyst or zeolite catalyst having hydrogenation and/or hydrocracking functions, either in the bottom of a single reactor or the second reactor of a two-reactor system.
[0012] In two-stage configurations, which can also be operated in a “recycle-to-extinction” mode of operation, the feedstock is refined by passing it over a hydrotreating catalyst bed in the first reactor. The effluents, together with the second stage effluents, are passed to a fractionator column to separate the H 2 S, NH 3 , light gases (C 1 -C 4 ), naphtha and diesel products which boil at a temperature range of 36-370° C. The unconverted bottoms, free of H 2 S, NH 3 , etc. are sent to the second stage for complete conversion. The hydrocarbons boiling above 370° C. are then recycled to the first stage reactor or the second stage reactor.
[0013] Hydrocracking unit effluents are sent to a distillation column to fractionate the naphtha, jet fuel/kerosene, diesel, and unconverted products which boil in the nominal ranges of 36-180° C., 180-240° C., 240-370° C. and above 370° C., respectively. The hydrocracked jet fuel/kerosene products (i.e., smoke point>25 mm) and diesel products (i.e., cetane number>52) are of high quality and well above worldwide transportation fuel specifications. While hydrocracking unit effluents generally have low aromaticity, any aromatics that remain will lower the key indicative properties of smoke point and cetane numbers for these products.
[0014] One major technical challenge posed in hydrotreating and/or hydrocracking heavy oil fractions or whole crude is the effect of small concentrations of contaminants, such as organic nickel or vanadium containing compounds, as well as poly nuclear aromatic compounds. These organometallic compounds, and others, reduce the activity or lifetime of hydrotreating catalysts. The contaminants and polynuclear aromatics cause reduced process performance, a need for increased capital, and operating costs of refinery processing units. The metals in the residual fraction of the crude oil deposit on the hydroprocessing catalyst pores and results in catalyst deactivation. These problems are addressed and solved in the disclosure which follows.
[0015] Conventional, prior art processes in the field of the invention involve distillation of crude oil, followed by treatment of the light fractions (naptha and diesel fuel) which remain following distillation. These light fractions are desulfurized and/or treated (i.e., “reforming” in the case of naphtha) to improve their quality, and are then sent to fuel pools for further use. The vacuum residium, referred to supra, is treated via solvent deasphalting, so as to secure deasphalted oil and asphalt. Asphalt is then further treated, by being gasified, or it is sent to the “asphalt pool.”
[0016] Prior art processes show the treatment of fractionates or distillates of crude oil, rather than treatment of crude oil per se, as in accordance with the invention. See, e.g., PCT/EP2008/005210 where distillates are used to produce asphaltenes and DAO; U.S. Pat. No. 3,902,991, wherein a vacuum residuum is solvent extracted followed by hydrocracking and gasification of the DAO and asphalt; published U.S. Patent Application 2011/0198266, showing treatment of a vacuum residue; published U.S. Patent Application 2008/0223754, where residues from a distillation process are used to manufacture asphaltene and DAO; and EP 683 218, which also teaches treating residual hydrocarbon products. Also see, e.g., U.S. Pat. Nos. 8,110,090; 7,347,051; 6,357,526; 6,241,874; 5,958,365; 5,384,297; 4,938,682; 4,039,429; and 2,940,920, as well as Published U.S. Patent Application 2006/0272983; PCT/KR2010/007651, European Patent Application 99 141; and Published Japanese Patent Application 8-231965. All references discussed herein are incorporated by reference in their entirety.
[0017] The current invention simplifies and improves the prior art process, by eliminating the need for distillation, and for treating the naptha and diesel fractions. Rather, the invention, as will be seen, simplifies whole crude oil processing by hydrocracking the whole stream, and eliminating the steps referred to supra.
[0018] How the invention is achieved will be seen in the disclosure which follows.
BRIEF DESCRIPTION OF THE DRAWING
[0019] FIG. 1 shows a schematic depiction of the process of the invention, suing a single reactor embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] The invention may be best understood by referring to FIG. 1 , which illustrates the general method of the invention as well as a system used in its practice.
[0021] Referring to FIG. 1 , a feedstream of crude oil “ 10 ” is added to a reaction chamber “ 11 ,” so as to solvent deasphaltize it, thereby producing an asphalt fraction “ 12 ,” and a fraction of deasphalted oil, or “DAO 13 ” as referred to supra. The manner in which this fractionation can be accomplished is described, supra, i.e., a paraffinic solvent containing one or more carbon atoms containing from 3-8 carbons, is used. No catalyst or adsorbent is necessary; however, see U.S. Pat. No. 7,566,394, incorporated by reference, supra, teaching an improved deasphalting process using a sorbent. No distillation is used, nor are the light components separated.
[0022] The “DAO” “ 13 ” is transferred to a hydrocracking/hydrotreating zone “ 14 .” It is to be understood that, while FIG. 1 describes a single reactor, the various methods for hydrocracking, including “once through, series flow,” and “two-stage” reactions, may all be used. The reactor contains one or more catalysts which remove heteroatoms, such as sulfur and nitrogen from the DAO. Such catalysts are well known to the art, and are not repeated herein. Exemplary of such are catalysts described in, e.g., PCT/US11/46272 filed Aug. 2, 2011 and incorporated by reference herein. The cracking reaction takes place in the presence of hydrogen, which is supplied as explained infra.
[0023] It will be recalled that in addition to the DAO, solvent deasphalting of the crude oil produces an asphalt fraction “ 12 .” This asphalt fraction is transferred to a gasification chamber “ 15 ,” together with oxygen “ 16 ” and steam “ 17 ” These components, i.e., the oxygen and steam, may be supplied in pure form, or via, e.g., atmospheric air. The asphalt, oxygen and steam are combined, at temperatures and pressures which result in production of hydrogen. In the depicted embodiment, this hydrogen “ 18 ,” is channeled to the DAO hydrocracking unit “ 14 ,” to supply the hydrogen necessary for the hydrocracking process to take place. (It should be noted that the gasification of asphalt is an optional step, and may be replaced via, e.g., supplying an independent source of hydrogen). Various products, e.g., gases 19 , and upgraded crude oil 20 , result, and products of gasification 21 are used in the generation of electricity or for other uses.
[0024] By separating the asphalt component of the crude oil from the DAO, one eliminates problems such as the failing of catalysts by metals that are present in the asphalt fraction. Catalyst life cycles are increased, and the need for shut downs of reactors, and replacement of materials, are decreased.
[0025] In the process as described herein, the hydrocracking process takes place at standard hydrocracking conditions, i.e., pressures ranging from about 100 to about 200 bars, temperatures ranging from about 350° C. (to about 450° C., LHSVs of between 0.1 and 4.0 h −1 , and hydrogen oil ratios of from about 500 to about 2,500 SLt/Lt.
EXAMPLE
[0026] This example describes an embodiment of the invention in which gasification of the “SDA” fraction was used to produce hydrogen, which was then used in the hydrocracking of the DAO fraction. It will be understood that the H 2 may be supplied via other means.
[0027] A 1000 kg sample of crude oil was solvent deasphalted, using art known techniques, with butane solvents and adsorbents, in a reaction chamber, such as is depicted by “ 11 ” in FIG. 1 . Prior to deasphalting, the crude oil was analyzed, and the results of this analysis are presented in the Table, column 1, which follows.
[0028] Following deasphalting, the asphalt fraction and deasphalted oil, or “DAO,” were also analyzed, and these results are presented in columns 2 and 3 of the Table.
[0029] The asphalt fraction was gasified by oxygen and steam combining it into membrane wall reactor or gasification chamber, depicted at “ 14 ” in FIG. 1 . The mixture was heated to 1045° C., with a water to carbon ration of 0.6 (in terms of weight), and an oxygen:pitch ratio of 1.0.
[0030] After gasification was completed, the raw syngas product was combined with steam that was produced by either a boiler or process heat exchanger to a water gas shift (“WGS”) reactor, which was operated at 318° C., one bar of pressure, and a water to hydrogen ratio of 3. This increased hydrogen yield.
[0031] All analyses and results are presented in the table which follows and which is elaborated upon infra:
[0000]
TABLE
Summaries of Components
Column #
1
2
3
4
5
6
7
8
Stream#
10
13
12
19
20
16
17
18
Stream
Arab
Deasphalted
Asphalt
C1-C4
Upgraded
Oxygen
Steam
Hydrogen
Name
Heavy CO
Crude Oil
Crude Oil
Feedrate
kg
1000
922
78
4.8
930
78
46.8
13
Density
Kg/Lt
0.8904
0.876
1.210
0.825
API Gravity
°
27.4
30.0
−14.6
40.1
Carbon
W %
84.8233
85.04
78.36
Hydrogen
W %
12.18
12.83
6.43
Sulfur
W %
2.837
1.99
10.79
<20
Nitrogen
ppmw
1670
535
9575
<20
MCR
W %
8.2
2.55
61.3
Nickel
ppmw
16.4
1
582
<1
Vanadium
ppmw
56.4
1
172
<1
C5-
W %
7.8
Asphaltenes
C7-
W %
4.2
Asphaltenes
Toluene
W %
0.0008
insolubles
Ashes
W %
0.014
H2
W %
99.5
H2S
W %
2.47
NH3
W %
0.11
C1-C4
W %
100
36-190
W %
17.4
20.6
21.5
190-370
W %
25.8
29.0
36.0
370-490
W %
17.9
19.1
21.2
490+-
W %
39.0
31.3
21.2
[0032] While gasification was taking place, the DAO portion was introduced to a standard, hydrocracking unit, shown in “ 14 ,” and hydrocracked at 360° C., 115 bars of hydrogen partial pressure, with an overall liquid hourly space velocity of 0.3 h −1 , with a Ni—Mo promoted, amorphous VGO hydrocracking catalyst and a VGO zeolite catalyst, at a loading ratio of 3:1. See PCT/US11/46272, incorporated supra, for the catalyst used herein.
[0033] The products which left the hydrocracking chamber were analyzed for content of low molecular weight hydrocarbons (C 1 -C 4 ), upgraded crude oil, oxygen, steam, and hydrogen. These values are presented in columns 4-5 in the Table. The upgraded crude oil was also analyzed for various minor components, as well as boiling fractions, in the same way the crude oil, and DAO were analyzed. To elaborate upon the Table, Column 1 presents the analysis of the crude oil (“CO”) used in the reaction. Column 2 is the analysis of the resulting DAO and Column 3, the asphalt fraction. Column 4 presents the information on the gas produced in the hydrocracking step, with Column 5, the upgraded crude oil. Finally, Columns 6, 7, and 8 refer to the reactants added to the reactors, as discussed supra.
[0034] The foregoing disclosure sets forth the features of the invention, which is a simplified methodology for reducing impurities, such as sulfur and nitrogen, in a feedstock, such as crude oil, which does not involve distillation. To summarize, the crude oil is solvent deasphalted, resulting in DAO and asphalt. The DAO is then hydrocracked in the presence of a catalyst so as to desulfurize and denitrogenize it, and to convert any hydrocarbons which have a boiling point over 370° C. into distillates. Concurrently, the asphalt fraction is gasified so as to produce hydrogen. In one embodiment, the hydrogen is channeled back into the hydrocracking reactor and used in that process. The nature of the feedstock will, of course vary and may include ash in an amount ranging from about 2% to about 10% of the total feedstock. The feedstock may be liquid or solid. Liquid feedstocks having components with boiling points of from about 36° C. to about 2000° C. are preferred. The feedstock may be, e.g., bituminous, oil, sand, shale oil, coal, or a bio liquid, and preferably contains less than 20 ppmw of sulfur.
[0035] In practice, it is desirable to subject the crude oil to a paraffinic solvent to separate DAO and asphalt. The solvent comprises one or more C 3 -C 7 alkanes, which may be straight chained or branched. Preferably, the solvent comprises one or, most preferably, a mixture of butanes. Solvation takes place at temperatures and pressures, which are below the critical values for both of these.
[0036] It is especially preferred to carry out the deasphalting step, discussed, in the presence of a solid adsorbent, preferably added in an amount sufficient to provide a hydrocarbon:adsorbent ratio of from 20:0.1 to 10:1, expressed in terms of W/W.
[0037] After separation, the DAO is transmitted to a hydrocracking unit, where hydrocracking is carried out at conditions which may vary, but are preferably a pressure of from about 100 to about 200 bars, a temperature of from about 350° C. to about 500° C., an LHSV of from about 0.1 to about 4.0 h −1 , and a hydrogen:oil ratio of from about 500 to about 2500 SLt/Lt. Any standard hydrocracking system may be used including single reactors, multiple reactors operated in series, fixed bed reactors, ebullated bed reactors, and so forth.
[0038] A catalyst is used in the hydrocracking process, preferably the catalyst incorporated by reference supra. Preferably, the catalyst contains from about 2% to about 40% by weight of active metal, a total pore volume of from about 0.3 to about 1.5 cc/g, a total surface area of from about 200 to about 450 m 2 /g, and an average pore diameter of at least 50 angstroms.
[0039] With respect to the active metal, referred to supra, metals from Group VI, VII or VIIIB are preferred, and may include one or more of Co, Ni, W, and Mo. While it is not required to do so, the catalysts are generally incorporated on a support, such as alumina, silica, a zeolite or a zeolite modified by, e.g., steam, ammonia, acid washing and/or insertion of transition metals into its structure.
[0040] Concurrent with the hydrocracking of the DAO, the asphalt portion of the crude oil is gasified in a gasification chamber, e.g., a membrane wall type reactor, preferably at a temperature of from about 900° C. to about 1700° C., and a pressure of from about 20 bars to about 100 bars. Gasification takes place in the presence of an O 2 containing gas, which may be, e.g., pure O 2 or more preferably, atmospheric gas. Means may be provided to control the amounts of asphalt and oxygen entering the gasification reactor. Such means are well known to the skilled artisan and need not reiterated here. It is preferred t control the amounts of asphalt and O 2 , so that a stoichiometric balance permitting partial combustion ensues. This can be determined via determining the hydrocarbon content of the crude oil, such as was done in the example, supra. Preferably, the amounts are selected such that the oxygen:carbon ratio ranges from about 0.2:1.0 to about 5:0.1 by weight.
[0041] Optionally, steam may be added to the gasification chamber. When it is, it too is added in an amount based upon the carbon content of the crude oil, and is preferably presented at a ratio of from about 0.1:1.0 to about 100:1.0 by weight. Gasification results in a product sometimes referred to as “syngas” consisting essentially of hydrogen and carbon monoxide. In one embodiment of the invention, the syngas produced by gasification is transmitted to a water gas shift reaction chamber and treated to produce H 2 and CO 2 , after which H 2 is separated. The resulting, pure H 2 may be channeled to the hydrocracking reaction.
[0042] The process by which the syngas is treated may include treatment at a temperature of from about 150° C. to about 400° C., and a pressure of from about 1 to about 60 bars.
[0043] As was seen, supra, gas content can be measured at any point in the process described here. Hence, following measurement of CO content in the syngas, water can be added to the reaction chamber, preferably at a molar ratio with CO of from about 3:1 to about 5:1.
[0044] Other facts of the invention will be clear to the skilled artisan and need not be reiterated here.
[0045] The terms and expression which have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expression of excluding any equivalents of the features shown and described or portions thereof, it being recognized that various modifications are possible within the scope of the invention.
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The invention relates to processes for removing impurities, such as asphalt, from whole crude oil. The invention is accomplished by first deasphalting a feedstock, followed by processing resulting DAO and asphalt fractions. The DAO fraction is hydrocracked, resulting in removal of sulfur and hydrocarbons which boil at temperatures over 370° C., and gasifying the asphalt portion.
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BACKGROUND OF THE INVENTION
This invention relates generally to multiple glazed units and in particular to an improved spacer assembly for spacing apart the glass panes or glazing panels of such a unit.
As is well known in the art, in multiple glazed units, two or more glazing panels are secured in spaced apart parallel relationship to one another by peripheral edge spacers and adhered thereto by a suitable sealing composition applied between each panel and and the spacer. The spacer is often a hollow tubular spacer and it usually contains a desiccant to absorb moisture from the space between the glazing panels to thus avoid condensation problems. In the case of tubular spacers, the same are commonly roll-formed into the desired profile shape.
Many conventional spacer designs do not provide adequate space or room for the desiccant material. Hence, after a period of time, the moisture absorbing capability of the desiccant is exceeded and condensation begins to appear on the interior surfaces of the glazing panels.
Another problem common to conventional spacer designs is related to the fact that the inner wall of the spacer is readily visible and often presents a rather undesirable appearance in that it is not of the same colour as the frame surrounding the glazing unit. It is not practical to produce and market differently coloured spacer bars.
Another difficulty inherent in the pesent spacer arrangements is that they typically provide an easy path for the transmission of heat from one glazing panel to the other. As a result of this, under low temperature conditions, a frost line around the perimeter of the glazing unit is often present. Another problem is that a rigid spacer provides an excellent path for the transmission of sound from the outer panel to the inside panel. This poses a particular problem in high-noise areas such as airports. Other institutions such as hospitals also have a need for low sound transmission glazing units.
Another problem with conventional glazing units is related to the problem of deflection of the glazing panels under the influence of high winds, traffic noise, or internal pressure changes owing to expansion or contraction of the air mass contained within the glazing unit. This action imposes high stresses on the glazing panels and can break the seal between the spacer and the glazing units thus allowing moisture to enter and in extreme cases breakage of the glazing panel can occur.
Since the spacer must extend completely around the marginal portion of the glazing unit, special provisions must be made for the corners. In the most common constructions used to date, the spacer is miter-cut at the corner locations and spliced together by means of a special corner pieces. This creates a number of problems since the corner pieces and the required assembly procedure increases manufacturing costs substantially; moreover the spacer assembly is weaker at these corners and the corner piece assembly often affords a path for moisture to seep into the interior of the glazed unit from the outside.
Efforts have been made in the past to provide a spacer bar arrangement having right angle bends at the corners; however these designs do not appear to have found wide acceptance apparently because the bending process causes substantial distortion of the spacer tube profile and moreover, the strength at the bend is often significantly impaired.
In other instances it may be desirable to use muntin bars between the panes for decorative or reinforcement purposes. In the past it has been a problem to secure them securly to the spacers so there is no danger of them slipping out of position in response to vibration and the like.
SUMMARY OF THE INVENTION
It is therefore a basic object of the invention to provide an improved spacer for a multiple glazed unit which solves or alleviates the problems noted above.
It is a further object of the invention to provide a spacer tube design which is arranged to receive a snap-on cap. A further object is to provide a spacer tube arrangement having a snap-on cap of any desired colour thereby to match the surrounding structure. Another object is to provide a spacer tube which can be bent into a rectangular outline shape without the use of separate corner inserts. A further object is to provide a spacer with a snap-on cap which is capable of holding a desiccant material. A still further object is to provide a spacer arrangement including a filler cap so designed as to provide thermal and/or sound insulation between the glazing panels. A further object is to provide a spacer arrangement incorporating a filler cap having suitable means therein to securely hold a decorative grill or the like in place between the glazing panels. A further important object is to provide a spacer unit which is capable of flexing in such a manner as to accommodate relative movement between the glazing units in response to fluctuations in the forces acting on the glazing panels thereby to reduce the possibility of damage occuring to the glazing unit.
Accordingly the invention herein concerns improvements in a spacer including a tubular body having a inner web which in use faces inwardly toward the space between the pair of glazing panels and an outer web which in use faces in the opposite direction away from the panels. The spacer includes a pair of elongated flanges disposed at opposing sides of the tubular spacer in flanking relation to the inner web. Each flange includes an inner and an outer wall with the outer flange walls lying outboard of the remainder of the tubular spacer and normally being generally parallel to one another so that they may be positioned in proximity to or in abutting relation to the inner surfaces of the glazing panels when in use.
As a very desirable feature of the invention the inner flange walls have a configuration such that the distance between them becomes smaller a selected distance away from the inner web thereby to define a re-entrant or dovetail-like region bounded by the inner flange walls and the inner web. This arrangement facilitates the securement to the flanges and over the inner web of a snap-on cap.
The above-noted re-entrant region may be provided in several ways. The inner flange walls may gradually decrease in a direction away from the inner web such as by being inclined toward each other in a direction away from the inner web or alternatively the inner flange walls may each have a convex hump thereon to provide the gradual reduction in distance. Alternatively the distance between the inner flange walls may decrease abruptly as by providing an abrupt step to provide the re-entrant region.
In the preferred form of the invention the tubular body includes, in addition to the above-noted inner and outer webs, a pair of opposed body side walls which extend between the outer web and the flange outer walls. A shoulder portion between each body side wall and the associated flange outer wall defines an inwardly directed step by way of which the body sidewalls are stepped inwardly of the flange outer walls. In use, a sealant material occupies the space provided by the these inwardly directed steps between the body sidewalls and the inner walls at the edges of the glazing panels.
As a further feature of the invention the flange outer walls are spaced from the flange inner walls thereby to permit inward or outward movement of the flange outer walls during use in response to pressure fluctuations on glazing panels engaged with same. The flanges are also capable of flexing and pivotting relative to the tubular body of the spacer to accommodate flexure of glazing panels in contact therewith. This feature reduces glazing panel breakage and breakage of the seal between the panels and the spacer as a result of these pressure fluctuations etc.
As a further feature of the invention the spacer may include at least one smoothly contoured right angle bend therein adapted to be positioned at a corner of the glazing unit.
The invention further provides a glazing unit including a spaced pair of glazing panels and a spacer as described herein extending around the perimeter of the unit between the panels and sealingly engaged therewith. The spacer will be provided with a smoothly contoured right angle bend at each of the corners of the glazing unit.
As a further important feature of the invention the spacer as described includes a snap-on cap, such cap having resilient portions engaged with the inner flange walls of the spacer to releasable secure the cap to the spacer body. Preferably the cap defines a space between itself and the inner web of the spacer, such space in use holding a suitable desiccant material.
In a preferred form, the snap-on cap includes a top wall with the resilient portions thereof being in the form of a pair of resilient legs extending from the top wall in spaced apart relationship. The outer distal end of each leg may have an outwardly turned lip adapted to engage with the inner flange wall portion and to cooperate therewith so that during installation or removal of the cap such legs spring inwardly to provide the desired snap action.
The cap may be of roll formed or extruded metal pre-painted in the desired colour to provide a pleasing appearance when in use. In an important alternative arrangement the cap may be of a resilient plastic material and may include oppositely directed lobes engaged with abrupt steps defined by the inner flange walls of the spacer to secure the cap in place. In this case the cap itself defines an elongated cavity for retention of desiccant and apertures are provided in the cap for communicating the space between the glazing panels with the desiccant cavity.
In another version the cap includes down turned strips along each of the longitudinal margins of its top wall, which strips are arranged to overlie substantial portions of the flange outer walls so that in use these strips are interposed between the flange outer walls and the glazing panels. As a further important feature, the cap is of a suitable plastic material and the down-turned strips noted above are of sufficient thickness that in use they provide thermal insulation and/or sound insulation between the glazing panels. As will be readily apparent this thermal insulating capability is of importance in improving the heat loss characteristics of a building structure and reduces problems of condensation and frost line formation resulting from thermal transmisson. The improvement in sound insulation is of particular value in noisy environments and in places where low sound transmisson is desired as in hospitals.
The glazing unit, according to a still further feature of the invention, includes a snap-on cap engaged with the flanges of the spacer, such cap having a top wall overlying the inner web of the spacer body. A series of muntin bars are arranged in a selected array between the glazing panels for decorative and/or reinforcement purposes. The snap-on cap is provided with means, such as suitable apertures receiving end portions of the muntin bars, for securing the muntin bars in position thereby to resist vibration forces and the like.
In a still further major aspect of the invention there is provided a spacer including a tubular body and having a pair of outwardly and oppositely facing walls which are normally in paallelism with one another and which are adapted to engage or abut the inner surfaces of the spaced glazing panels when in use. The tubular spacer body is constructed so as to provide flexible inner and outer structures which serve to connect the oppositely facing walls with one another in such a fashion that the oppositely facing walls are capable of moving toward or away from one another and/or to rotate slightly relative to one another in response to pressure fluctuations and/or flexure of the glazing panels in contact therewith.
As a still further aspect of the invention there is provided a glazing unit comprising an elongated tubular spacer positioned between a pair of glazing panels adjacent the perimeter of same. The spacer includes a tubular body and means thereon defining a pair of oppositely directed wall portions arranged parallel to and in juxtaposition to the inner surfaces of the glazing panels. The tubular body includes an inner web portion facing inwardly toward the space defined between the panels and an elongated snap-on cap is engaged with the spacer in overlying relation to the inner web portion.
Further aspects and features of the invention will become apparent from the following description of preferred embodiments of same coupled with the accompanying claims.
BRIEF DESCRIPTION OF THE VIEWS OF DRAWINGS
FIG. 1 is an exploded perspective view showing a portion of the spacer adjacent a corner as well as a portion of its snap-on cap and a muntin bar;
FIG. 2 is an exploded side elevation view of a portion of the spacer bar, cap and muntin bar or grill assembly;
FIG. 3 is a perspective view of a portion of a spacer illustrating miter cut outs at the bend area;
FIG. 4 is a cross-section view of a portion of a glazing unit illustrating the spacer tube and desiccant filled snap-on cap and a sealant material for sealing a spacer to the glazing panel;
FIG. 5 is a cross-section similar to that of FIG. 4 but illustrating the desiccant as located inside of the tubular spacer body;
FIG. 6 is a further cross-section of the glazing unit illustrating the modified form of spacer tube and its snap-on cap, the cap being of a relatively deep profile with the desiccant located in the cap;
FIG. 7 is a section view similar to that of FIG. 6 but illustrating the use of desiccant within the tubular spacer itself and also showing a dual sealant system;
FIG. 8 is a further section view illustrating a spacer tube similar to that of FIGS. 4 and 5 showing the use of a deformable plastic snap-on cap of modified design, which cap has a longitudinal cavity filled with desiccant;
FIG. 9 is a further section view similar to that of FIG. 8 but illustrating a modified cap arrangement which provides thermal and/or sound insulation;
FIG. 10 is a further section view of a spacer tube and cap assembly only, the snap-on cap being adapted to provide a desired colour only;
FIG. 11 is a further section view illustrating a cap configuration generally similar to that of FIG. 9 but lacking any thermal break or soundproofing means;
FIG. 12 is a further section view of a glazing unit illustrating the flexing action of the spacer in response to typical motions of the marginal portions of the glazing panels;
FIG. 13 is a view similar to that of FIG. 12 illustrating the manner in which the spacer expands and contracts in response to pressure fluctuations acting on the glazing units; and
FIG. 14 is a view of a modified form of spacer incorporating a raised central or internal web portion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference now to FIG. 1 there is shown an elongated spacer 10 adapted to be positioned between a pair of glazing panels adjacent the perimeters of same. The spacer includes a tubular body 12 having an inner web 14 which, in use, faces inwardly toward the space between the glazing panels, and an outer web 16 which, in use, faces outwardly in the opposite direction away from the panels. The spacer further includes a pair of elongated flanges 18 disposed at opposing sides of the tubular body in flanking relation to the inner web 14. Each flange 18 includes an inner wall 20 and an outer wall 22. The outer flange walls 22 lie in positions outboard of the remainder of the tubular spacer and these walls 22 are normally positioned in parallelism with one another. These walls are adapted to be positioned in proximity to or to abut the inner surfaces of the glazing panels when in use.
The inner flange walls 20 have a configuration such that the distance between them becomes smaller a selected distance away from the inner web 14 thereby to define a re-entrant or dove tail groove-like region which, as described hereafter, facilitates the securement to the flanges 18 and over the inner web 14 of a snap-on cap.
With continued reference to FIG. 1 as well as to FIGS. 4, 5, 10 and 11, it will be seen that the inner flange walls 20 are inclined toward each other in a direction away from the inner web 14 to provide a gradual reduction in distance in the direction away from the inner web 14 thereby to define a dove tail groove-like region.
The spacer includes a snap-on cap 30 as illustrated in the drawings and with particular reference to FIG. 1 it will be seen that the cap 30 includes a top wall 32 and a pair of resilient legs 34 extending downwardly from positions located inwardly of the margins of the top wall 32 and in a spaced apart relation. The outer distal end of each leg 34 is provided with an outwardly turned lip 36, which lips 36 are adapted to engage with the respective flange inner walls 20 and to cooperate therewith such that during installation or removal of the cap 30 on the spacer body, these legs 34 are caused to spring inwardly toward each other to provide a snap action.
Returning now to the spacer body itself, it will be seen that it includes, in addition to the inner and outer webs 14 and 16, a pair of opposed body side walls 26. Side walls 26 extend between the margins of the outer web 16 and the flange outer walls 22. A shoulder portion 28 is defined between each body side wall 26 and the associated flange outer wall 22, which shoulder defines an inwardly direct step by way of which the body side walls 26 are stepped inwardly of the flange outer walls 22.
With reference to FIG. 2, in the assembly of the glazing unit, the spacer 10 is provided with suitably spaced apart 90 degree bends illustrated as item 40. This 90 degree bend is accomplished with the aid of a fixture (not shown) which provides the bend with a relatively small generally circular curve 42. It has been found that the spacer tube configurations described herein are well suited for bending without significant buckling or distortion problems. By providing a small circular curve, buckling of the spacer flanges 18 is substantially avoided without the need for effecting miter cut outs in the flanges unless the flanges are relatively deep, in which event the flanges may be cut as shown in FIG. 3. This corner bend provides for a very sturdy and rigid corner arrangement considering the stiffness imparted by flanges 18 as well as the box beam-like tubular spacer body.
It should be noted here that in the case where the tubular body is provided with relatively deep flanges 18a, 18b as illustrated in FIGS. 6 and 7, that it may be necessary to miter cut the flanges as illustrated in FIG. 3 prior to effecting the 90° bends shown in FIG. 2. These miter cuts are designated by a reference characters 66. Miter cuts 66 can also be used in the embodiments of FIGS. 1 and 4-5 if a relatively sharp corner bend is desired. However, in all cases, care should be taken not to cut through the inner web 14 of the spacer as this would tend to unnecessarily weaken the spacer at the corner position and also allow desiccant leakage.
The spacer 10, after bending, is assembled together as required using a straight connector plug 44 at each of the joints in the spacer. Each joint is located between the corners 40 in a straight section of the spacer.
After the spacer has been bent as required and assembled together utilizing the plugs 44, its elongated caps 30 are snapped into place such that they interengage with the flange inner walls 20 as previously described.
In certain installations it may be desirable to provide a decorative and/or reinforcing arrangement of muntin bars 46 as illustrated in FIG. 2. As shown here the muntin bars 46 are arranged in a rectangular grid-like array, commonly referred to as a colonial grill. In order to secure the array of muntin bars in position, the snap-on caps 30 are provided with spaced apart apertures 48 which receive the ends of the muntin bars 46 thereby holding the colonial grill firmly in position and preventing dislodgement of same and possible damage to the glazing panels in the event of vibration and the like.
Reference will now be had particularly to FIGS. 4-9 which illustrate cross-sectional views of peripheral edge portions of glazing units incorporating spacer assemblies in accordance with the present invention. In FIGS. 4 and 5 the spacer 10 is shown together with its snap-on cap 30, the spacer 10 being sealingly engaged with the glazing panels G by means of a suitable sealant material 50. It should be noted from FIGS. 1, 4 and 5 that the top wall 32 of the cap is provided with a series of small breather holes 52. The inner web 14 is likewise provided with a series of spaced apart breather holes 54. As shown in FIG. 4, the elongated rectangular space provided between the top wall 32 of the snap-on cap and the bottom wall of the cap is filled with a suitable desiccant. The breather holes 52 provide a way for the moisture trapped between the glazing panels G to migrate into the desiccant D.
FIG. 5 illustrates a very similar form of structure. Insofar as structural changes are concerned it will be noted that the flange inner walls 20 are provided with spaced apart longitudinal grooves 60. These grooves 60 provide a means whereby the outwardly turned lips 36 of the snap-on cap 30 more positively engage with the inner flange walls 20 thereby to strongly resist removal of snap-on cap 30. In FIG. 1, for example, this resistance to removal of the snap-on cap is somewhat less since in this case the resistence to removal is provided by the inward incline of flange inner walls 20 and the outward bias of the legs 34 causing the outwardly turned lips 36 to engage with these inner walls 20. Further, in the embodiment of FIG. 5, it will be noted that the hollow body 12 of the spacer is itself filled with the desiccant D and that the upper chamber defined below the top wall of cap 30 is empty. The moisture migrates into the desiccant D by way of the previously described breather holes 52 and 54. In the arrangement shown in FIG. 5 the snap-on cap 30 provides a decorative function, it being kept in mind that in all cases, the snap-on cap is coloured such as to provide an attractive appearance when seen from the outside of the glazing unit.
It should also be kept in mind that in the event additional desiccant is required it is also possible to fill the space below the top wall of the cap 30 with desiccant as illustrated in FIG. 4.
Referring now to FIG. 6 a modified form of spacer with cap is illustrated. The spacer 10a incorporates the basic features described previously with reference to Figure 4 except that the flanges 18a are of greater highth than described previously while the tubular body portion 12a is relatively shallow. The legs of the cap 34a are correspondingly greater in highth as compared with those described previously. Furthermore, the flange inner walls 20a are not inclined in the manner described previously but, rather, such inner walls are arranged so as to provide small but abrupt steps 60a, which steps 60a, as shown in FIG. 6, are positioned as to interfere with the outwardly turned lips 36a of the snap-on cap thereby to strongly resist removal of the snap-on cap.
The relatively deep snap-on cap illustrated in FIG. 6 is provided, as before, with breather holes 52 while the spacer body is provided with breather holes 54. The relatively large depth of the cap 30a permits a very large quantity of desiccant D to be positioned within the space defined between the top of the snap-on cap and the bottom wall of the cap. The sealing compound is illustrated as 50a in FIG. 6, it being noted that the sealing compound has been forced upwardly into a position between the flange outer walls 22a and the glazing panels G.
FIG. 7 illustrates a spacer arrangement similar to that of FIG. 6. However, it will be noted that the flange inner walls 20b are provided with a longitudinally extending convex hump 64, which convex hump provides the re-entrant region referred to previously, with the outwardly turned lips 36b of the cap being engaged beneath these humps 64 to securely retain the snap-on cap 30b in position. In the arrangement of FIG. 7, the desiccant D is shown as being positioned in the relatively small chamber provided by the low-highth tubular spacer body. However, it should be kept in mind that the upper chamber or region defined below the top wall of the snap-on cap may be filled with desiccant D if conditions require an extra amount of desiccant.
The FIG. 7 embodiment is also suitable for use with dual sealant systems. It will be noted here that a first sealing compound 50b is interposed between the flange outer walls and the glazing units G, such sealant filling the concave recess as provided in the flange outer walls. This provides the primary sealing function while the secondary sealing function is provided by sealant by sealant 51b which occupies the remaining space and covers the outer web 16b of the spacer etc.
With reference now to FIGS. 8 and 9, modified forms of snap-on caps 30c and 30d are illustrated. The body of spacer 10c in both embodiments is similar to that described in FIGS. 1, 4 and 5 except that the flanges thereof have been modified so that the inner flange wall 20c defines an abrupt inward step whereby to define the re-entrant or dove tail-like groove 24c. With particular reference to FIG. 8 it will be seen that the snap-on cap 30c is of a Nylon, fiberglass or Neoprene rubber material. The use of certain plastic materials which create vapours when heated during hot sunny days is to be avoided. The cap includes oppositely directed lobes 68 extending the length thereof, which lobes are engaged with the abrupt steps defined by the flange inner walls 20c. This arrangement serves to secure the cap 30c in place. With further reference to FIG. 8 it will be seen that the cap defines an elongated cavity 70 for retention of desiccant D. Breather holes 52c in the top wall of the snap-on cap provide communication between desiccant D and the space between the glazing panels G.
A modified form of cap arrangement 30d is illustrated in FIG. 9. The basic configuration of the cap 30d is the same as that described with reference to cap 30c in FIG. 8; however in the arrangement of FIG. 9, the cap 30d further includes down turned strips 74 along each of the longitudinal margins of the top wall of the cap, which strips 74 are arranged to overlie the flange outer walls 22c. Thus, it will be seen that these strips 74 are interposed between the flange outer walls and the glazing panels G. By making these down turned strips 74 of sufficient thickness and by making the cap of a suitable thermal insulating or sound absorbing material such as fiberglass or neoprene rubber, a substantial degree of thermal insulation and sound insulation is provided between the glazing panels thus reducing heat and/or sound transmission from one glazing panel G to the next.
With reference to FIG. 10, the spacer 10 is again shown which in itself conforms with that illustrated in FIG. 1. A very simple form of snap-on cap 30e is provided which is arranged such that no space is provided between itself and the inner web 14 of the spacer. This snap-on cap 30e is provided for decorative purposes only. As described previously, it is painted or otherwise coated so as to provide an attractive overall appearance to the structure. Suitable vent holes 52e and 54 are provided as described previously.
In the structure of FIG. 11 a still further form of snap-on cap 30f is provided. This snap-on cap includes the basic feature of the snap-on cap described with reference to FIGS. 1, 4 and 5 except that it also includes down turned marginal side portions 74f which overlie the flange outer walls 22f. Again, this snap-on cap 30f is utilized here primarily for decorative purposes and is painted or otherwise coated to provide the desired colour effect.
A further important feature of the improved spacer design is illustrated in FIGS. 12 and 13. It is of It was previously noted that changes in the forces acting on the glazing panels G imposed large stresses on such panels thus, in some cases, causing cracking and breakage of the panels and/or disruption of the seal between the panels thus allowing the ingress of moisture.
It was previously noted that there is a space between the inner and outer flange walls 20 and 22. course clear from the drawings that the inner and outer flange walls 20, 22 are connected to each other only along distal portions of the flanges 18, i.e. portions remote from inner web 14. It will also be noted that there is a small gap between the opposing ends of the inner web 14 and flange outer wall 22 just above shoulder 28 and designated by reference character S. By virtue of these clearance spaces it will be appreciated that the flange outer walls 22 are free to move back and forth slightly relative to one another and that moreover, the flanges 18 are capable of pivotting slightly relative to the spacer body about the pivot point P as illustrated in FIG. 12. The full line and dashed line positions of the glazing panels G and flanges 18 are exaggerated for purposes of illustration. In actual practice the amount of deflection will be quite small; nevertheless it is definitely present and unless freedom of movement is permitted by virtue of the arrangement illustrated in FIG. 12, serious damage may occur. By allowing the pivotting action illustrated in FIG. 12 to take place, a reduction in breakage owing to pressure fluctuations etc. will be noticed and moreover there should be less disruption of the sealant arising from such causes.
With reference to FIG. 13, expansion and contraction of the air between the glazing panels G causes them to move inwardly or outwardly slightly and, by virtue of the space between the inner and outer flange walls 20 and 22 as well as the clearance space S noted above, the flange outer walls 22 can move toward and away from one another thereby decreasing the stresses imposed on the glazing panels G and assisting in avoiding disruption of the seal between such panels.
A further modification of the spacer is illustrated in FIG. 14. In this modification the inner web 14g includes a raised central portion defining oppositely disposed downwardly extending ramp portions 15g. These downwardly extending and outwardly sloping ramp portions 15g aid in locating the snap-on cap 30 and they can assist in pushing the legs 34 outwardly towards the sides of the spacer for more secure holding power. Furthermore, the raised central portion increases the size of the cavity defined by the spacer body thereby enabling it to hold more desiccant.
The spacer structures herein described including the snap-on caps may be readily formed from sheet aluminum by convention roll-forming techniques. Seams and the like may be locked tight by use of a staking wheel which contains small teeth to stake the metal. Alternatively, the seams in the spacer tube can be seam-welded. Alternatively, the aluminum sections could be extruded; in the case of the snap-on caps illustrated in FIGS. 8 and 9 the nylon cap is of course extruded.
Conventional desiccant materials may be utilized. The desiccant may be poured into the end of the cavity defined by the tubular spacer body or the spacer tube may be filled during the rollforming process before the seam is closed up. In the case where the desiccant is to be retained by the snap-on cap, the desiccant first of all may be placed in tea-bag type pouches with the latter being subsequently placed in the cap at suitable locations to provide the desired effect.
By using the snap-on cap, in addition to the advantages noted previously, the manufacturers logo and date stamp may conveniently be applied to the cap.
Numerous variations and modifications will readily occur to those skilled in this art upon reading the above description, and without departing from the spirit or scope of the invention. For definitions of the invention reference is to be had to the appended claims.
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A spacer tube design is arranged to receive a snap-on cap which may be of any desired color thereby to match the surrounding structure. The spacer tube can be bent into a rectangular outline shape without the use of separate corner inserts. The snap-on cap may be capable of holding a deisiccant material. The cap may be also designed as to provide thermal and/or sound insulation between the glazing panels and/or to securely hold a decorative grill or the like in place between the glazing panels. The spacer unit may be capable of flexing in such a manner as to accommodate relative movement between the glazing units in response to fluctuations in the forces acting on the glazing panels thereby to reduce the possibility of damage occurring to the glazing unit.
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FIELD OF THE INVENTION
[0001] The present invention relates generally to recovery of sulphur from oil and gas processing, and more particularly to the removal of sulphurous compounds from gaseous streams produced during industrial processes, thereby releasing “clean gas” containing minimal amounts of sulphurous compounds.
BACKGROUND OF THE INVENTION
[0002] A hazard associated with the petroleum industry is the atmospheric release of the toxic gas hydrogen sulphide (H 2 S). H 2 S is found in various gas streams, such as raw sour gas streams or in gas streams (such as tail gas streams) arising from industrial operations where fuels containing sulphur and other combustible materials are burned. H 2 S, being extremely toxic, must in accordance with regulations be removed before the by-products from such industrial operations can be released into the atmosphere. Regulations have necessitated the development of methodologies to recover sulphur and reduce the amounts of each of H 2 S and SO 2 released into the atmosphere.
[0003] Conventionally, the amount of sulphur released into the atmosphere is reduced by converting H 2 S and SO 2 into elemental sulphur. The method commonly used by industry today is known as the modified Claus process, first developed by the London chemist Carl Friedrich Claus in 1883. This method is based on the Claus reaction:
[0000] 2H 2 S+SO 2 ⅜S 8 +2H 2 O (1)
[0004] The modified Claus process is a two step process: 1) the oxidation of H 2 S to SO 2 in a reaction furnace according to the equation:
[0000] H 2 S+⅜O 2 →SO 2 +H 2 O (2)
[0005] and 2) the reaction of SO 2 and residual H 2 S into elemental sulphur via the Claus reaction (1). The second step, the reaction of H 2 S and SO 2 into elemental sulphur is typically completed using a series of catalytic reactors, because the Claus reaction is an equilibrium reaction. Consequently, it is typical to use several catalytic reactors in series, with elemental sulphur incrementally removed at each reactor, to achieve greater sulphur recovery.
[0006] Unfortunately, thermodynamically, one does not recover all the sulphur by employing only a series of Claus reactors. A small amount of H 2 S remains in the tail gas stream, thereby necessitating the additional step of tail gas clean up (hereinafter “TGCU”).
[0007] There are a total of 16 TGCU processes known to be in use, 9 of which are proven technologies. TGCU units are typically used together with either Claus or modified Claus sulphur recovery units (hereinafter “SRU”).
[0008] A typical SRU involves a raw gas feed stream passing through an amine treating unit that absorbs H 2 S and then desorbs it, thereby concentrating the H 2 S. This concentrated H 2 S then enters a reaction furnace where it is combusted in an oxygen rich environment, producing H 2 S and SO 2 in accordance with reaction (3) below.
[0000] H 2 S+ a O 2 b H 2 S+ c SO 2 +d S (elemental) +e COS+ f CS 2 +g H 2 O (3)
[0009] Elemental S and H 2 O are then removed from the partially treated gas stream by condensation that lowers the temperature of the gas stream, which is then passed through a series of catalytic converters where COS, CS 2 , and elemental S are removed. H 2 S and SO 2 undergo the Claus reaction (1) above, while COS and CS 2 mainly undergo different reactions (4) and (5) to produce H 2 O and elemental sulphur.
[0000] COS+H 2 O→CO 2 +H 2 S (4)
[0000] CS 2 +2H 2 O→CO 2 +2H 2 S (5)
[0010] Disadvantageously, after a series of catalytic converters progressively remove sulphur from the gas stream, the use of catalytic converters is no longer efficient, so a small portion of the original H 2 S and produced SO 2 are released into the atmosphere with the treated exhaust.
[0011] The following known patents teach different improvements to the above conventional method of removing sulphurous compounds from industrial gas streams.
[0012] U.S. Pat. No. 4,138,473 to Gieck (the '473 patent, issued Feb. 6, 1979) teaches the use of pure oxygen to combust H 2 S into SO 2 . Further, the use of three catalytic converters in series is combined with the repressurization and reheating of the gas stream before entering the next catalytic converter in the series, each converting H 2 S and SO 2 into H 2 O and elemental sulphur. SO 2 is then recycled back to the start of the process as fuel for use in the Claus reaction (1). The '473 patent further teaches that the stoichiometric ratio between H 2 S and SO 2 maintained at 2:1 offers maximum efficiency. Disadvantageously, the '473 technology depends on an oxygen rich environment for its oxidation of H 2 S, leading to uncontrolled combustion of H 2 S, resulting in an excess of SO 2 needing to be reduced to elemental sulphur by the catalytic converters. This excess production of SO 2 also requires a TGCU unit to scrub out the excess SO 2 , thereby higher cost.
[0013] U.S. Pat. No. 4,895,670 to Sartori (issued Jan. 23, 1990) and U.S. Pat. No. 4,961,873 to Ho (issued Oct. 9, 1990) each teach the use of an amine scrubber to absorb H 2 S and concentrate it prior to entering the reaction furnace 130 (with reference to FIG. 1 ). Disadvantageously, neither of these patents overcomes the necessity of using a TGCU unit.
[0014] U.S. Pat. No. 4,071,436 to Blanton (issued Jan. 31, 1978) teaches the use of various catalysts (e.g. alumina, typically in a fluidized bed or embedded on the surface of a moving bed) in a converter to help drive the Claus reaction (1). Disadvantageously, these technologies still require the use of a TGCU before the exhaust gases can be released to atmosphere.
[0015] An oxygen rich environment has been typical of conventional sulphur recovery until recently. However, US Patent Application 2005/0158235 to Ramani, (published Jul. 25, 2005) teaches the limited use of oxygen during the oxidation of H 2 S to lower the SO 2 introduced to subsequent stages and thereby in the exhaust. Disadvantageously, US Application 2005/0158235 necessitates the use of a TGCU unit to remove residual SO 2 in the exhaust.
[0016] US Patent Application 2006/0078491 to Lynn (published Apr. 13, 2006) teaches treating a gas stream using an excess of SO 2 within an organic liquid environment such as poly glycol ether (or other tertiary amine solution), according to a process in which the stoichiometric ratio between H 2 S and SO 2 should be maintained lower than 2:1. This process eliminates the need for an amine scrubber and absorber. Disadvantageously, this also results in a higher concentration of SO 2 entering the catalytic converters, which SO 2 must be recycled back to the start of the process as fuel for use in the Claus reaction (1), like the process taught in '473.
[0017] It is, therefore, desirable to provide a less costly methodology for recovering sulphur from sour gas streams, which process does not necessitate the use of a TGCU unit in order to meet modern environmental standards.
SUMMARY OF THE INVENTION
[0018] It is an object of the present invention to eliminate the need for a TGCU unit when recovering sulphur from sour gas streams.
[0019] In one broad aspect of the invention, a process for removing sulphurous compounds including H 2 S from an industrial gas stream is provided comprising the steps of: feeding the industrial gas stream into a reaction furnace; combusting the industrial gas stream so as to oxidize H 2 S therefrom in said furnace under sufficiently oxygen-deficient conditions so as to maintain a stoichiometric ratio between H 2 S and SO 2 to be greater than 2:1; condensing the combusted gas stream so as to precipitate H 2 O and elemental sulphur therefrom; converting the remaining products from the combustion of H 2 S to elemental sulphur, using a conventional modified Claus reactor; condensing the catalyzed gas stream so as to further precipitate H 2 O and elemental sulphur therefrom; scrubbing unconverted H 2 S out of the treated gaseous stream and concentrate using a secondary regenerator; and recycling any unconverted H 2 S to a reaction furnace. Preferably, the industrial gas stream is pre-scrubbed in a pre-existing primary amine treatment unit.
[0020] Another object of the present invention is to take advantage of an oxygen deficient environment that exists inside a typical reaction furnace. The method of present invention uses such oxygen deficient environment to control the stoichiometric ratio between the H 2 S and SO 2 entering the catalytic converters, and then recycles residual H 2 S back to an amine treating unit.
[0021] Thermodynamically, the Claus reaction (1) is an equilibrium reaction the dissociation constant of which is:
[0000] K p =[S 8 ] 3/8 [H 2 O] 2 /[H 2 S] 2 [SO 2 ] (6)
[0022] According to a method of the present invention a gas feed stream first enters an amine treating unit in order to concentrate the H 2 S in that raw stream. The concentrated H 2 S then enters a reaction furnace where it is subjected to an oxygen deficient environment, which in turn results in less SO 2 leaving the furnace, such that the stoichiometric ratio between H 2 S and SO 2 is greater than 2:1.
[0023] The concentrated H 2 S in the primary gas stream entering the furnace is oxidized according to combustion reaction (3) thereby producing SO 2 , H 2 S, COS and CS 2 and H 2 O. This is a complete reaction, only dependant upon the availability of the reactants, H 2 S and O 2 . Advantageously, limiting the amount of O 2 present during the combustion of H 2 S results in a lower production of the by-product SO 2 needing to undergo catalytic conversion.
[0024] In accordance with the dissociation equation (6), a high concentration of H 2 S necessarily produces a low concentration of SO 2 , since at a constant temperature the concentration of SO 2 is inversely proportional to the concentration of H 2 S squared. In an oxygen-deficient environment the Claus reaction (1) produces a higher concentration of H 2 S and a lower concentration of SO 2 as compared to the modified Claus reaction, which produces H 2 S and SO 2 in a stoichiometric ratio of 2:1.
[0025] H 2 O and elemental sulphur precipitate out of the gas stream by condensation. COS and CS 2 continue along in the gas stream and enter a catalytic converter where they are subjected to reactions (4) and (5) to produce H 2 O and elemental sulphur. The H 2 S and SO 2 , (in said stoichiometric ratio greater than 2:1) also enter a catalytic converter, where the Claus reaction (1) produces H 2 O and elemental sulphur.
[0026] Residual H 2 S is removed by a secondary amine scrubber and recycled back to primary regenerator to increase the amount of H 2 S available for oxidation in the furnace. In an alternative embodiment, residual H 2 S may be removed by the secondary amine scrubber, regenerated by a secondary regenerator, and recycled to the reaction furnace. It should be noted that the primary amine scrubber and regenerator are not part of the proposed sulphur recovery unit, but part of a pre-existing amine treating unit (hereinafter “ATU”).
[0027] An embodiment of the process of this present invention for removing sulphurous compounds, from an industrial gas stream flowing through a fluidly coupled system comprises a primary scrubber (of a pre-existing ATU), a primary regenerator (of a preexisting ATU), a reaction furnace, suitable controllers and sensors, at least two condensers, at least one catalytic converter, and a secondary scrubber.
[0028] The primary scrubber and primary regenerator scrubs H 2 S from the industrial gaseous stream and concentrates the H 2 S. The concentrated H 2 S enters the reaction furnace under oxygen deficient conditions and is oxidized. The oxidized gas stream enters a condenser to precipitate out H 2 O and elemental sulphur. The remaining gases, are catalyzed in a conventional modified Claus reactor to further produce elemental sulphur and H 2 O. Any unconverted H 2 S is further scrubbed by the secondary scrubber and then recycled through the primary regenerator to re-enter the reaction furnace.
[0029] One embodiment of the system of this present invention for removing sulphurous compounds, from an industrial gaseous stream flow, comprises a primary scrubber and a primary regenerator, both of a pre-existing ATU. These are to scrub and concentrate H 2 S from an industrial gaseous stream.
[0030] The system further comprises a reaction furnace, to oxidize the concentrated H 2 S, condensers to precipitate out elemental sulphur and H 2 O, a conventional modified Claus reactor, suitable sensors and controllers and a secondary scrubber. The system also recycles the scrubbed H 2 S back to the primary regenerator.
[0031] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the method and system according to the invention and, together with the description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The present invention, in order to be easily understood and practiced, is set out in the following non-limiting examples shown in the accompanying drawings, in which:
[0033] FIG. 1 is a schematic diagram illustrating a preferred embodiment of the system of the invention;
[0034] FIG. 2 is a schematic diagram illustrating an alternate embodiment of the system of the invention incorporating a stabilizer;
[0035] FIG. 3 is a flow chart demonstrating the preferred embodiment of the process;
[0036] FIG. 4 is a schematic diagram illustrating an alternate embodiment of the system of the invention incorporating a secondary regenerator;
[0037] FIG. 5 is a flow chart demonstrating an alternate embodiment of the process incorporating a secondary regenerator;
[0038] FIG. 6 is a schematic diagram of the preferred embodiment of the invention demonstrating the mathematical relationship existing between each step of the process; and
[0039] FIG. 7 is a table demonstrating sulphur recovery according to Example 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] Referring to FIG. 1 , there is illustrated one embodiment of a system, the sulphur recovery unit (hereinafter “SRU”) denoted generally as 400 , in which a primary gas feed stream enters primary scrubber (of a pre-existing ATU) 110 where H 2 S is absorbed from the gas stream and is thereafter concentrated in primary regenerator (of a pre-existing ATU) 120 , such that purified and concentrated H 2 S enters reaction furnace 130 . The SRU sensor # 1 161 , monitors the amount of H 2 S entering furnace 130 and provides a feed forward signal to SRU control unit 150 , which regulates the amount of air entering furnace 130 via O 2 Control Valve 165 , so as to maintain an oxygen-deficient environment and achieve the designed combustion of H 2 S.
[0041] As shown in FIG. 2 , the purified and concentrated H 2 S can be stabilized inside a stabilizer 125 prior to enter the reaction furnace 130 .
[0042] H 2 S is oxidized by O 2 in furnace 130 to produce gaseous forms of elemental sulphur, H 2 O, COS, CS 2 , and SO 2 . All products then enter condenser # 1 140 . Inside condenser # 1 140 , the gas stream temperature is lowered sufficiently that H 2 O and elemental sulphur precipitate out, leaving the gaseous form of each of COS, CS 2 , H 2 S and SO 2 to flow into catalytic converter 160 , which is any suitable conventional catalytic converter.
[0043] SRU sensor # 2 162 measures the amount of H 2 S and SO 2 entering catalytic converter 160 and also sends a feed back signal to SRU control unit 150 , which combines that signal with the feed forward signal from SRU sensor # 1 161 in order to regulate the amount of air entering furnace 130 , and thereby the results of oxidation reaction (3), by maintaining the stoichiometric ratio between H 2 S and SO 2 at greater than 2:1, such that a controlled amount of SO 2 is produced during the initial oxidative process in furnace 130 .
[0044] Inside catalytic converter 160 the reactants undergo the Claus reaction (1) to produce elemental sulphur, COS, CS 2 , and H 2 O. COS and CS 2 also undergo reactions (4) and (5) to further produce H 2 O and elemental sulphur. Any suitable catalyst may be used to facilitate the Claus reaction. Maintaining the stoichiometric ratio between H 2 S and SO 2 at greater than 2:1 advantageously controls the amount of H 2 S and SO 2 entering catalytic converter 160 , which is achieved by SRU control unit 150 using feed back signals from SRU sensor # 2 162 monitoring the amount of H 2 S and SO 2 entering catalytic converter 160 .
[0045] The treated gas stream leaving catalytic converter 160 enters condenser # 2 170 to further precipitate out both H 2 O and elemental sulphur. After which, the treated gas stream leaving condenser # 2 170 flows into a downstream secondary scrubber 180 where excess H 2 S is absorbed and any unconverted H 2 S is recycled back to primary regenerator 120 .
[0046] As illustrated in the flow chart of FIG. 3 , the process conducted in the system of FIGS. 1 and 2 comprises scrubbing and concentrating H 2 S from a gaseous feed stream at 900 . The scrubbed H 2 S then is oxidized at 910 according to the present invention. Water and elemental sulphur are precipitated at 920 . H 2 S, SO 2 , COS and CS 2 are reacted at 930 . Water and elemental sulphur are precipitated at 940 . Unconverted H 2 S is scrubbed from the gas stream at 950 . Unconverted H 2 S is recycled back to the primary regenerator at 960 .
[0047] With reference to FIG. 4 , in the event that primary regenerator 120 is not available, then, an alternative embodiment would comprise of a secondary regenerator 190 after the secondary scrubber 180 , and such that the recycling of the H 2 S would be to the reaction furnace 130 . Advantageously, secondary scrubber 180 is a smaller and less expensive component than primary scrubber 110 used in the initial stage of the inventive process.
[0048] Further, secondary scrubber 180 is incorporated into sulphur recovery unit 400 .
[0049] As illustrated in the flow chart of FIG. 5 , the process conducted in the system of FIG. 4 comprises scrubbing and concentrating H 2 S from a gaseous feed stream at 900 . The scrubbed H 2 S then is oxidized at 910 according to the present invention. Water and elemental sulphur are precipitated at 920 . H 2 S, SO 2 , COS and CS 2 are reacted at 930 . Water and elemental sulphur are precipitated at 940 . Unconverted H 2 S is scrubbed from the gas stream at 950 . Unconverted H 2 S can be regenerated at 955 and recycled back to the reaction furnace at 965 .
EXAMPLE 1
[0050] A series of calculations were performed to determine the potential efficiency of a system based on the present invention, including the recycling of untreated H 2 S from secondary scrubber 180 . The results of these simulations are shown in FIG. 7 .
[0051] The calculations were based on a schematic diagram representing the preferred embodiment of the present invention (See FIG. 6 ).
[0052] The definitions of the variables used are as follows:
[0053] x=amount of sulphur in the primary gas inlet stream (ie. sour gas) entering furnace 140 in moles/hour;
[0054] R=amount of recycled H 2 S re-entering furnace 130 from secondary scrubber 180 (in reference to FIG. 1 ) in moles/hour;
[0055] P=amount of H 2 S leaving furnace 130 in moles/hour;
[0056] Q=amount of SO 2 leaving furnace 130 in moles/hour;
[0057] S=amount of elemental sulphur that is removed from furnace 130 in moles/hour;
[0058] a=efficiency of sulphur recovery in furnace 130 , typically between 40-50%;
[0059] b=efficiency of sulphur recovery in the catalytic converter, typically between 60-90%; and
[0060] c=efficiency of sulphur recovery in the amine scrubber, typically between 90-99.9%.
[0061] As shown in the table of FIG. 7 , assuming a recovery of sulphur efficiency of 50%, in furnace 130 , as the molar ratio between H 2 S and SO 2 increase, the efficiency of sulphur recovery varies between 99.0% at the minimum to a maximum of 99.9% recovery. Also accompanying the increase in the stoichiometric ratio between H 2 S and SO 2 is the increase in the amount of H 2 S that is required to be recycled back to primary regenerator 120 .
[0062] In accordance with FIG. 7 , a molar ratio of 3:1 (H 2 S:SO 2 ), results in an efficiency of 99.9% sulphur recovery. Advantageously, this percentage recovery is far greater than those currently required by environmental regulations in many countries. According to the method of the invention, depriving reaction furnace 130 of oxygen, in any manner that maintains the stoichiometric ratio between H 2 S and SO 2 at greater than 2:1, in combination with recycling residual H 2 S back to ATU regenerator 120 , as taught herein, eliminates the need for and expense of a TGCU, while still meeting or exceeding current environmental standards.
[0063] In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.
[0064] Although the disclosure describes and illustrates various embodiments of the invention, it is to be understood that the invention is not limited to these particular embodiments. Many variations and modifications will now occur to those skilled in the art of sulphur recovery. For full definition of the scope of the invention, reference is to be made to the appended claims.
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There is described a novel process for removing sulphurous compounds from industrial gaseous streams, such as sour gas, using an oxygen deficient environment during the oxidation of H 2 S, and further recycling of any unconverted H 2 S back to a regenerator.
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BACKGROUND AND SUMMARY OF THE INVENTION
The manufacture of packages in which semiconductor devices, particularly those with flat leads, may be shipped has been a problem. Heretofore such devices have typically been shipped in packages such as polyethylene bags which offer little protection to the flat leads, or rigid boxes which offer protection but are expensive to manufacture.
In accordance with the illustrated preferred embodiment, the present invention provides a package in which semiconductor devices, including those with flat leads, may be simply contained while protection is provided against bending of the leads. The preferred structure is of a flexible material such as plastic and includes a hollow central region to house the main body of the semiconductor device, and a flat portion against which the leads of the device are contrained, e.g., by means of a strip of tape. Structural rigidity is provided to the package by an outer flange. A number of such structures may be included in a single strip, thereby enabling the efficient packaging of semiconductor devices.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective drawing including a cross-section of a preferred embodiment of a package element taken along a line A--A in FIG. 2.
FIG. 2 illustrates a package including a number of package elements arranged in a strip.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1 there is illustrated a piece of packaging material 11, for example thin plastic sheets of thickness about 0.01 inches. A raised central area 13 and a raised ridge or flange-like portion 15 are stamped into sheet 11 in accordance with processes well known in the art. In the preferred embodiment of FIG. 1 both of the raised portions are shown as being essentially circular and having conical cross-sections. However, it will be evident to those skilled in the art that other configurations may be employed.
A semiconductor device 17 such as a microwave transistor is also illustrated in FIG. 1. Transistor 17 is shown as including four flat leads, labeled 19, 20, 21, and 22. In the packaging of transistor 17, the central portion of the transistor is fitted into central region 13 of the package. Flat leads 19, 20, 21, and 22 are brought into contact with a region 23 of the bottom of sheet 11 between raised regions 13 and 15. The transistor is held in place by a piece of restraining material 27, e.g., a thin piece of tape.
Construction of a package according to these principals provides protection against bending of the flat leads. More particularly, it has been found that the raised ridge 15 prevents bending of sheet 11 in the interior region 23 adjacent to the flat leads even when the sheet is generally subjected to bending forces. Thus, the flat leads are prevented from bending or other deformation.
In FIG. 2 there are shown a number of structures such as that described in FIG. 1, these structures being arranged in strip-like fashion on one piece of material 11. This arrangement makes possible the inexpensive fabrication of the package and also provides for the simple packaging of a large number of transistors.
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A package for flat lead transistors is provided in which a raised flange provides structural rigidity to prevent damage to the flat leads of the transistor.
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The present application is a division of prior application Ser. No. 206,514, filed on Nov. 13, 1980, now U.S. Pat. No. 4,432,867 granted Feb. 21, 1984, by Sanford N. Smith for Method and Apparatus for Separating Particulate Materials from Fibrous Materials.
The present invention relates to a method for removing entrained, dense particulate materials from an elongated body of less dense fibrous materials. More specifically, the present invention relates to a method and apparatus for removing entrained balls from yars being transported by a moving fluid stream.
Synthetic fibers are commonly produced by extruding molten polymer through a spinneret. Obviously, the filaments thus produced are smooth and lack the bulk and hand possessed by natural materials such as wool. In order to produce yarns which have properties approximating those of wool or other natural materials, it is common practice to subject the extruded filaments to a texturing process. This can be accomplished by a variety of procedures known in the art, such as stuffer-box crimping, false twist texturing and fluid jet texturing. One particularly effective procedure involves contacting the fibrous materials with a high velocity fluid stream in a turbulent zone and at an elevated temperature. The turbulence imparted to the fiber materials produces crimps which give the fiber a textured bulky appearance. It has more recently been found that improved texturing can be accomplished by passing the yarn from the turbulent zone through a chamber which contains a plurality of discrete particulate elements, such as balls. These balls exert a force on the yarn to produce a wad which extends through the chamber. The yarn wad can then be passed into the inlet end of an elongated tube provided with one or more openings intermediate the ends thereof. A fluid, such as air, is passed through the tube toward the inlet end, with a substantial quantity of the fluid being vented through the openings. The fluid thus exerts a retarding force which tends to prevent breakup of the yarn wad until the yarn has been cooled. Usually the wad is broken up and a single yarn withdrawn adjacent the openings in the tube. The cooled textured yarn is then withdrawn from the outlet end of the tube.
During startup, which of course requires stringing of the yarn through the various apparatus and formation of the wad, it is conventional practice to introduce fluid into the tube downstream of the openings in the tube and in a direction so that the flow of the fluid through the tube will be toward the outlet end and such fluid will act to aspirate the yarn through the tube. This aspirating fluid may be introduced into the tube itself as part of the operation by an appropriate valve system which then reverses the flow toward the inlet end after the operation has become stabilized, or, as is the usual case, the aspirator is a separate flexible tube, usually hand-held by an operator. In any event, during the startup operation and until the wad has formed and the operation has become stabilized, it is conventional practice to pass the aspirated yarn to a waste area or bin. Although the startup time is usually of relatively short duration, the cumulative startups necessitated by restringing of the apparatus due to breaks or other malfunctions become quite significant in commercial operations. Consequently, significant amounts of yarns are passed to waste, which is a saleable item. However, it has been found that a significant number of the balls are entrained in the yarn carried by the fluid stream while the wad is being formed and before the operation has become stabilized. Accordingly, these balls are carried along the flow line, drop out at various points along the flow line, and at times are carried over into the waste. Irrespective of where the balls end up, there is obviously a significant loss of the balls, which is a significant cost factor, but, in addition, natural separation of the balls from the waste yarn, dropping of the balls on the floors, and the carryover of the balls into the waste, which is sold for various purposes, all constitute safety hazards.
It is therefore an object of the present invention to provide an improved method and apparatus for separating entrained, dense particulate materials from an elongated body of less dense fibrous materials. Another and further object of the present invention is to provide an improved method for removing entrained, dense particulate materials from an elongated body of less dense fibrous materials and retrieving the particulate materials. A further object of the present invention is to provide a method and apparatus for removing entrained dense particulate materials from a synthetic yarn being transported by a moving fluid stream. Another object of the present invention is to provide an improved method and apparatus for removing small balls from a synthetic fibrous material being transported by a moving fluid stream. A still further object of the present invention is to provide an improved method and apparatus for removing balls from a synthetic yarn being transported by a fluid stream, which balls have become entrained in the yarn during the texturing of said yarn. These and other objects and advantages of the present invention will be apparent from the following description when read in conjunction with the drawings.
SUMMARY OF THE INVENTION
In accordance with the present invention, entrained, dense particulate materials are removed from an elongated body of less dense fibrous materials being transported by a moving fluid stream by reducing the velocity of said fluid stream by an amount and for a time sufficient to release a substantial portion of said dense particulate materials, but insufficient to stop the transport of the elongated body of less dense fibrous material by the moving fluid stream.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified flow diagram, partially in section, of a portion of a yarn processing line, including one embodiment of the present invention;
FIG. 2 is an elevational view, partially in section, showing the embodiment of FIG. 1 of the present invention in greater detail;
FIG. 3 is an elevational view, partially in section, of another embodiment of the present invention;
FIG. 4 is a side view of yet another embodiment of the present invention;
FIG. 5 is a right hand end view of the embodiment of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1 of the drawings, it is to be understood that the drawing does not necessarily depict the actual relative sizes, shapes and spatial relationships of the various pieces of equipment illustrated but that the figure is for illustrative purposes only and various items of equipment have been enlarged and/or distorted to some extent for such illustrative purposes.
As previously indicated, synthetic fibers are generally produced by extruding molten polymer through a spinneret or spinnerets in order to produce individual filaments. Upon solidification of the filaments, the filaments are generally collected into groups to form yarns which may be more readily handled in subsequent processing. After collection of a plurality of filaments to form a tow or yarn, the yarn is generally wound up to form a package. In a commercial operation, a plurality of such yarn packages can be produced in a single production line or a single package produced from a plurality of spinnerets. In any event, the yarns, thus produced and wound up to form individual packages of yarn, are generally referred to as "as spun" yarns to the extent that the yarns have not been processed in any manner to alter the properties thereof except to the extent that a certain degree of drawing of the yarn has taken place during the spinning operation itself. It should be recognized, of course, that numerous operations designed to alter the properties of the fibrous materials thus produced can be carried out during the spinning operation, i.e., before windup. However, for purposes of the present description, it is assumed that the fibrous materials utilized are undrawn yarns in their "as spun" condition. When synthetic fibers are to be further treated by texturing, as in the present application, it is common practice to combine a plurality of yarns from a plurality of packages of undrawn yarns to produce a yarn of the desired total denier. Such a yarn is illustrated by the line 10 of FIG. 1. Yarn 10 is then passed over a tensioning gate or tensioning pins 12 to provide better control of the yarn. The yarn is then fed to a heated feed roll 14 and onto a heated draw roll 16. Either or both of these rolles are suitable for use as a heating zone or a heating means. The draw ratio should be the highest ratio consistent with good drawing performance. The yarn is then fed to a suitable crimping means or texturing means denoted by reference numeral 18. In the embodiment illustrated, the crimping means 18 is a fluid jet crimper, as is known in the art. However, other crimping means such as a stuffer-box crimper could be used. The only limitation imposed on the crimping means 18 is that it be of the type which produces a yarn plug. The crimping means 18 contains a fluid jet portion 20 and a chamber 22 containing a plurality a stacked members 24, such as small balls. A suitable heating fluid such as steam enters the fluid jet portion 20 of crimper 18 by way of line 26. The steam heats the yarn 10, assists in crimping and exits the crimper by way of line 28 and through the stacked members or balls 24. While it is not necessary, an adjustable angle idler 30 may be used to insert a controllable amount of false twist into the yarn prior to crimping. This is useful in controlling heat losses from the yarn and, hence, the yarn temperature entering the crimping means 18. The yarn plug 32 formed in the crimping means 18 is passed through a tube 34 in which the yarn plug 32 is broken up and cooled by countercurrent air entering the tube through line 36 or other suitable cooling fluid supplied through line 38. The major portion of the air entering through line 36 exits through openings 40 in tube 34. In any event, the back pressure of the air through line 36 is sufficient to maintain the plug 32 in the tube 34 for a time sufficient to completely cool the yarn and thereby set the crimp by the time the yarn plug reaches the openings 40. In actual practice, the process is generally controlled in a manner such that the end 42 of plug 32 is maintained adjacent the openings 40 in the tube 34. Tube 34 may be straight or curved, as shown, and the openings 40 may be positioned in the vertical or horizontal portion of tube 34. After the plug 32 is broken up, the crimped yarn 44 is withdrawn, passed over appropriate tensioning pins or tensioning gate 46, and thereafter further processed. Such further processing can, for example, include entangling the yarn, cutting it into staple or simply winding the yarn up to form a package. In general, a large number of relatively small balls 24 are present in chamber 22. These balls can be formed of metal, glass or any other material which is inert to the yarn and temperatures encountered. The balls are advantageously spherical in nature but this is not essential to the operation. In addition, it is generally common practice to use larger balls having a diameter of about 1/4 inch in admixture with smaller balls having a diameter of about 1/8 inch. In such instance, approximately 75 percent of the total number of balls are the larger balls. Also in general practice, the balls are of metal and are generally ball bearings which are not suitable for use for their original purposes. However, they perform quite adequately when utilized in accordance with the present invention.
The details of the texturing and plug-forming apparatus can be found, for example, in U.S. Pat. No. 3,693,222 and 3,994,052.
Similarly the full process line and the control of the position of the end 42 of the plug 32 can be found in U.S. Pat. Nos. 4,012,816 and 4,135,511.
Obviously, during startup of the texturing operation, plug 32 will not be completely formed and the desired degree of texturing of the yarn will not have occurred. Therefore, the yarn produced during such startup time is not suitable for use as a finished product. Consequently, during startup and until the system has become stabilized and product quality yarn is being produced, the yarn is generally withdrawn some time prior to windup or the production of the final product and is passed to a waste area or waste receptable. This may be readily accomplished by the utilization of an aspirator tube 48 which draws waste yarn 50 from the normal path or the yarn by means of air supplied concurrently with the flow of the yarn through aspirator tube 48, which air is supplied through line 52. The aspirator tube 48 may be a part of tube 34 or preferably is a separate tube. During such startup operations and before the system has become stabilized and produces product quality yarn, and particularly while the plug 32 is being formed, it has been found that there is a tendency for a significant amount of the balls 24 to become entrained in the yarn. While the duration of the startup time is not great and thus the number of balls picked up at any given time will not be great, it is to be recognized that in a commercial operation many lines such as that illustrated in FIG. 1 are involved and because of yarn breaks and other system upsets, each line must be rethreaded and restarted any number of times. Consequently, over a period of time, in a commercial operation, the volume of balls entrained in the waste yarn 50 during startup is quite significant and their loss is a significant economic factor. In addition, the balls will, to some extent, drop out of the waste yarn 50 of their own accord, become scattered over the floors, and will sometimes be forcefully ejected and, in any event, thus become a safety hazard in an operation of this nature. Accordingly, in accordance with the present invention, it has been found that the waste yarn 50 may be substantially freed of entrained balls by reducing the velocity of the air stream 52 carrying the waste yarn 50. As illustrated in FIG. 1, this is accomplished by passing the waste yarn 50 from the end of the tube 48 through a zone or chamber 54 of expanded diameter or cross section. This sudden expansion reduces the velocity of the air carrying the waste yarn 50 and in doing so, also reduces the pressure and permits the balls to drop out of the waste yarn 50 of their own accord, of course, with the aid of gravity. The waste yarn 50 then passes through a reduced diameter tube 56 to a waste yarn storage bin or area 58. The balls which drop out of the waste yarn 50 in separator chamber 54 can be continuously or periodically collected in a container 60 and reused in the texturing apparatus.
FIG. 2 of the drawings illustrates in greater detail, the structure of a separator 54, such as that illustrated in FIG. 1. Specifically, separator 54 includes a tubular entry means 60, an intermediate expanded diameter portion or chamber means 62 and a tubular exit means 64. As shown in FIG. 2, the bottom of separator 54 between entry tube means 60 and the outer shell of the separator is frustoconical to form a lower collecting section 66. Section 66 of the separator is thus designed to collect balls separated from the yarn as it passes through the intermediate or midsection of separator 54. Collecting section 66 is provided with an opening 68 for removal of collected balls. Opening 68 may be open so as to remove balls continuously or it may be provided with a plug or door or other type of closure. Separator 54 also has an upper frustoconical section 70 formed by decreasing the diameter of midsection 62 to the diameter of exit means 64. This frustoconical section serves several purposes. First, balls which have been released from the moving yarn but which have a tendency to be carried downstream by the air in the separator 54 will strike the frustoconical sidewalls and drop to the bottom collection section 66. Secondly, the gradual tapering of section 70 aids in the passage of the yarn into and through tubular exit means 64.
By way of illustration, midsection 62 of separator 54 will generally vary in diameter between about 4 and 8 inches and will have a length anywhere between about 3 and 5 feet. In a specific commercially successful device, midsection 62 was made of 6 inch Schedule 10 aluminum pipe approximately 4 foot in length. Tubular entry means 60 was made of 11/2 inch O.D. aluminum tubing approximately 6 inches long with one inch extending above the frustoconical section. The frustoconical section was made of 14 gauge aluminum, welded between the entry tube and the body of separator 54. The discharge opening 68 was a hole approximately one inch in diameter. It should be recognized that the frustoconical bottom of the separator can be at any appropriate angle, the only requirement being that the separated balls will drop into and be collected in the bottom of the separator without interfering with the yarn as it is transported out of the upper end of entry tube 60. As the air transporting the yarn through tubular entry means 60 abruptly expands into the central or midportion 62 of the separator 54, a certain amount of reverse circulation of the air rearwardly into collection section 66 and "mixing" of the air takes place. Accordingly, this reverse circulation and mixing causes entrained balls to be released from the yarn and most of the balls will be separated in the first portion of midsection 62 adjacent the outlet opening of entry tube 60. However, it should be recognized that the reduction in velocity of the air stream transporting the yarn through separator 54, which is caused by such expansion, reverse circulation and mixing is insufficient to significantly affect the ability of the air stream to transport the yarn through the separator 54 and into and through the outlet tube 64. Even though the air expands and reverse circulation and mixing occur in midportion 62 of the separator, the main stream of the air will travel through the separator as a concentrated, axial core and the peripheral air around this core is still moving in a generally upward direction and again becomes concentrated through the outlet tube 64. The reduction in the velocity of the air stream in passing from the entry tube 60 to the outlet tube 64 will depend upon the relative cross-sectional dimensions of tubes 60 and 64 as compared with midsection 62, upon the actual weight or density of the yarn being carried by the air stream and upon the pressure of the air stream itself. For example, where the entry tube 60 and the exit tube 64 were 11/2 inches in diameter and midsection 62 of the separator 54 was 6 inches in diameter, the air stream utilized to transport the yarn through the separator and into a waste storage bin was supplied through a 3/8-inch pipe at a pressure of 90 psi. In order to "reconcentrate" the air and facilitate the passage of the air and yarn through exit tube 64, the frustoconical section 70 should be at an acute angle with respect to a diametric plane of the separator. More specifically, this angle may vary from the diametric plane anywhere up to about 45°. It has been found that, where the angle is zero and the exit end is essentially flat, the exit of the yarn through the exit tube 64 is interfered with and that, where the angle is greater than about 45°, difficulties are also experienced in feeding the yarn through the exit tube 64.
FIG. 3 of the drawings shows another embodiment of the separator of the present invention. In accordance with FIG. 3, the separator, designated generally by the numeral 72, comprises an expanded midsection or central portion 74, a tubular entry means 76, a tubular exit means 78, a lower collecting section 80, for collecting separated balls, and an upper frustoconical section 82 connecting the midsection 74 to the exit tube 78. As illustrated in FIG. 3, this embodiment of the separator has a sloping bottom disposed at an angle of about 10° from the horizontal and sloping downwardly toward an opening 82 for the removal of collected, separated balls. The sloping bottom may, of course, vary in the degree of slope and may be frustoconical as shown in FIG. 2 in addition to sloping as shown in FIG. 3, the only requirement being that collecting section 80 slopes toward the opening 82 to facilitate removal of collected balls. As in FIG. 2, the entry tube 76 extends through the bottom of separator 72--in this case, approximatey 4 inches--to provide the collection section 80 thereabout. The ball removal opening 82 may be provided with a hinged door 84 for periodically removing collected balls from separator 72. The relative dimensions of this embodiment of the invention are similar to those of the embodiment of FIG. 2, for example, the entry tube 76 and the exit tube 78 are each 11/2-inch O.D. aluminum tubing with the entry tube 76 being approximately 6 inches long and the exit tube approximately 3 inches long. The midsection is a 6 inch Schedule 10 aluminum pipe and the frustoconical section 82 has an angle of about 45° from a diametric plane.
While the embodiments of FIGS. 2 and 3 show separators which would be utilized in a vertically oriented manner, FIGS. 4 and 5 of the drawings illustrate another embodiment of the separator which can be utilized in a generally horizontal mode. While the vertically disposed embodiments shown in FIGS. 2 and 3 can advantageously be manufactured from readily available components and are relatively inexpensive to construct, certain advantages exist in the use of a horizontally disposed separator as shown in FIGS. 4 and 5. The separator of FIGS. 4 and 5 entry tube means 90 and an exit tube means 92, all of generally the same configuration and size as the embodiments of FIGS. 2 and 3. It should be noted, however, that in this embodiment, the entry tube 90 does not extend into the midsection or expanded portion 88 of the separator 86. This is true since it is not necessary in this embodiment to provide for a separating section adjacent the exit end of entry tube 90. This has a number of advantages. As the air transports the yarn through entry tube 90 an abrupt expansion of the air carrying the yarn into expanded section 88 of the separator 86 still occurs with consequent reverse circulation of the carrier air into the corners of the midsection 88 and consequent mixing and separation of the balls from the yarn. However, since the collection section rearwardly or upstream of the end of entry tube 90 is eliminated the pressure and velocity of the air carrying the yarn is not reduced to as great an extent and thus the overall pressure of the air necessary to carry the yarn through the separator 86 will be reduced and/or the dimensions of the separator 86 may be changed while maintaining the carrier air pressure the same. The utilization of separator 86 in a horizontal position also aids in the separation of the balls from the moving yarn, to the extent that the forces of gravity are acting all the way along the length of the yarn as it is passing through the central chamber 88. The bottom of separator 86 may take a number of different configurations, the only requirement being that it slope to a single point or area for collection and removal of the separated balls. For ease of manufacture, the embodiment of FIGS. 4 and 5 show a slot cut in the bottom of section 88 of separator 86 and two pieces of tubing split along their length at an angle and welded over the slot to form a collecting channel 96. The balls may be removed from collecting channel 96 through a collection tube 98 or simply through a hole in channel 96. If a hole is provided, the hole may be simply plugged or left open or it may be provided with a hinged door or the like. Similarly, the ball removal tube 98 may be provided with a hinged cover 100 as shown in the figures or simply a press fit cap or plug.
While specific dimensions and configurations have been shown in the drawings hereof and described in the specification, it is to be understood that references to materials of construction, dimensions and various elements and the general arrangements of parts can be varied without departing from the present invention and that one skilled in the art can, with little experimentation, determine appropriate sizes and materials of construction and operating conditions and procedures necessary to practice to present inventiion.
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In accordance with the present invention, entrained, dense particulate materials are removed from an elongated body of less dense fibrous materials being transported by a moving fluid stream by reducing the velocity of said fluid stream by an amount and for a time sufficient to release a substantial portion of said dense particulate materials, but insufficient to stop the transport of the elongated body of less dense fibrous material by the moving fluid stream.
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[0001] This application is based on provisional application No. 60/620,558 filed on Oct. 21, 2004
FIELD OF THE INVENTION
[0002] The present invention relates to augmented display of mobile head up display generally.
BACKGROUND OF THE INVENTION
[0003] The following U.S. patents are believed to represent the current state of the art:
6,866,918 3/2005 Sauer 428/172 6,927,674 8/2005 Harter, Jr. et al. 340/425.5 6,922,267 7/2005 Endo et al. 359/15 6,947,875 9/2005 Winkler, et al. 703/1 6,815,680 11/2004 Kormos 250/330 6,837,581 1/2005 Raines, et al. 353/13 6,847,336 1/2005 Lemelson, et al. 345/8 6,664,945 12/2003 Gyde, et al. 345/156 6,567,014 5/2003 Hansen, et al. 340/980 6,718,187 4/2004 Takagi, et al. 455/569.2 6,750,832 6/2004 Kleinschmidt 345/7 6,720,938 4/2004 Ohkawara, et al. 345/7 6,865,460 3/2005 Bray, et al. 701/36 6,731,436 5/2004 Ishii, et al. 359/630 6,771,403 8/2004 Endo, et al. 359/13 6,897,892 5/2005 Kormos 348/148 6,359,737 3/2002 Stringfellow 359/631 6,292,305 9/2001 Sakuma, et al. 359/649 6,262,848 7/2001 Anderson, et al. 359/630 6,445,506 9/2002 Eccles 359/631 6,559,761 5/2003 Miller, et al. 340/435 6,906,836 6/2005 Parker, et al. 359/15
SUMMARY OF THE INVENTION
[0004] The current invention provides augmented information on the go while reducing the hazards and risks that are related to using personal communication and computing devices while driving a vehicle. People are spending significant time within cars. In many cases using personal communicating and computing devices while driving force the driver's eyes off the road in order to watch information such as caller identification of a received cellular phone, viewing and flipping through a mobile address book before making a call, watch driving directions, view maps, or receive a textual, pictorial, or multimedia messages and information.
[0005] The Head-up Display (HUD) systems are well known and are being used for various mobile applications. Current invention diminishes at least some of the disadvantages associated with methods and solutions for displaying mobile and cellular information in a mobile environment. It enables Head-up Display (HUD) systems to be easily and seamlessly utilized with mobile applications.
[0006] Addressing the hazards of using cell phones while driving, modern car kits offer today wide remote LCD displays that are installed on the dashboard to enable the driver to view the cell phone parameters such as his address book with minimal diverting of his eyes. The large remote LCD display has not solved the need of the driver for changing his eyes focus from long to short range and visa versa, the need to view that data in a different light conditions and the additional eyes focus diversion all these components maintain the risk of using a cell phone while driving even with a large remote display.
[0007] Some lucrative cars have built in HUD systems that are wired to built in car systems such as Infra red imaging and navigation systems. Most cars do not have such HUD systems. Adding a HUD to a car would require complicated hardware and software interface and expensive wiring that would enable the HUD system to communicate and display a personal communicator data.
[0008] In one embodiment of present invention, a system that provides a vehicle's driver with, an augmented information and data within his Field-Of-View (FOV). The augmented information is wirelessly received from the driver's communicating or computing apparatus. Such a wireless apparatus can be a cell phone, a PDA, an infotainment (information-entertainment) system, a mobile computer, or a navigation system, or another infotainment (information-entertainment) system, such as satellite radio (i.e. XM-radio)
[0009] It would be appreciated that current invention provides seamless connectivity between the personal, portable communicating or mobile computing apparatus and a wireless HUD, which enable vehicle's drivers to easily and safely utilize their handheld communicating and computing devices while in the car and without taking their eyes off the road.
[0010] In another embodiment of present invention, a HUD that received image information from a portable computing or communicating apparatus and automatically reformats the images, text or video to match it to the HUD optical properties such as resolution and image size.
[0011] It would be appreciated that current invention enables seamless ubiquitous connectivity of the wireless HUD of current invention to most personal wireless communicators and portable computers. As a result layman would easily be able to install the wireless HUD and safely use it and by doing so, would increase safety driving. The wireless installation requires no wires and will keep the driver space free of wires.
[0012] In another embodiment of current invention is the HUD capabilities of getting into the drivers FOV on demand only and its ability to be dismissed on demand or on sever event such as a car collision. Yet in another embodiment of current invention is the HUD capability to automatically adjust the projected image intensity to match the visual conditions in the user's FOV
[0013] In another embodiment of current invention is the wireless HUD is connected to personal portable GPS enabling these portable devices to safely display augmented data such as maps and driving directions to the driver within his FOV and without taking his eyes off the road.
[0014] In another embodiment of current invention is the wireless HUD is wearable and is wirelessly connected to computing apparatuses such as personal computer, or infotainment (information-entertainment) system, or personal communicators or servers, enabling the user to wirelessly receive and augmented watch data and information that is received from these devices without the need to carry computers with him while performing his job and while enabling use both his hands for his tasks.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
[0016] FIG. 1 is a simplified partially pictorial functional block diagram illustrating a preferred embodiment of the present invention, including a wireless Head Up Display in connection with wireless communicator and a wireless network.
[0017] FIG. 2 is a simplified functional block diagram, illustrating various implementations of the functionality of FIG. 1 .
[0018] FIG. 3 is a simplified functional block diagram, illustrating another implementation of the functionality of FIGS. 1, 5 , and 7 ;
[0019] FIG. 4 is a simplified functional block diagram, illustrating various implementation aspects of the functionality of FIGS. 1, 5 , and 7 .
[0020] FIG. 5 a simplified partially pictorial functional block diagram illustrating another preferred embodiment of the present invention.
[0021] FIG. 7A a simplified partially pictorial functional block diagram illustrating another preferred embodiment of the present invention.
[0022] FIG. 7B a simplified partially pictorial functional block diagram illustrating another preferred embodiment of the present invention.
[0023] FIGS. 7C , D, E are pictorial views illustrating various implementation aspects of preferred embodiments of the present invention.
[0024] FIG. 10 a simplified partially pictorial functional block diagram illustrating a wearable HUD in connection with a mobile communicator.
[0025] FIG. 11 a simplified partially pictorial functional block diagram illustrating a wearable HUD in connection with a wireless network.
[0026] FIG. 12 is a simplified functional block diagram, illustrating various implementation aspects of the functionality of FIGS. 10, 11 .
[0027] FIG. 13 A , B, C, are simplified partially pictorial functional block diagrams illustrating some preferred embodiments of the present invention, including possible mechanical description.
[0028] FIG. 14 a simplified partially pictorial functional block diagram illustrating a mobile HUD in connection with input means.
[0029] FIG. 15 a simplified partially pictorial functional block diagram illustrating a mobile HUD in connection with various implementation aspects of input means.
[0030] FIG. 16 is a simplified functional block diagram, illustrating various implementation aspects of a monochrome mobile HUD.
[0031] FIG. 17A , is a simplified functional block diagram, illustrating various preferred implementation aspects of a color mobile HUD. FIG. 17B is a simplified flow-chart illustrating operation of the functionality shown in respective FIG. 17A .
[0032] FIG. 18A , B, C, are simplified functional block diagram, illustrating implementation aspects of another preferred embodiment of a color mobile HUD of current invention.
[0033] FIGS. 20A , B are a simplified partially pictorial functional block and flow diagrams illustrating preferred embodiments of the present invention, including a multiplicity of communicators in wireless and IP communication with a plurality of information servers centers and involving a mobile HUD of present invention.
[0034] FIG. 21 is a simplified flow-chart illustrating operation of the functionality shown in respective FIGS. 20A , B.
[0035] FIG. 24A is a simplified functional block diagram, illustrating implementation aspects of another preferred embodiment of a wireless apparatus with a built in HUD of current invention. FIG. 24B is a pictorial view of one possible implementation of FIG. 24A .
[0036] FIG. 25 A , B, C, D, E, F, G, H, I are simplified partially pictorial functional block diagrams illustrating some preferred embodiments of the present invention, including possible mechanical description.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0037] Reference is now made to FIG. 1 , which is a simplified partially pictorial functional block diagram illustrating a preferred embodiment of the present invention, including a wireless Head Up Display (HUD) operating in plurality of communication wireless networks.
[0038] The illustrated embodiment of FIG. 1 is presented in the context of cellular communications in a car, it is understood that this embodiment of the invention is not limited to cellular communications and is equally applicable to other suitable types of wireless communications networks and other vehicles and mobile applications.
[0039] In FIG. 1 , a Wireless Head Up Display (HUD) system 10 for providing augmented information 108 that is projected in front of a vehicle's operator 102 and within his field of view 110 .
[0040] A long-range communicator device 118 such as a cellular phone, a wireless PDA, or an infotainment (information-entertainment) system, wireless computing apparatus, a GPS, or a satellite communicator, or radio device is located within the vehicle cabinet. The communicator device 118 is long-range wirelessly connected 120 with a wireless network. Such long-range wireless connection 120 of current invention may be cellular network such as GSM, CDMA, GPRS, UMTS, WCDMA, 3G, 4G, or Wi-Fi, WiMax, satellite, GPS, and other long-range RF networks, satellite communication, digital terrestrial, or satellite TV and radio, such as XM radio, special and proprietary wireless networks and new communication networks.
[0041] Information which the vehicle's operator 102 needs is wirelessly transferred using a short range wireless link 114 to the Wireless Head Up Display (HUD) projector 100 that may be located near the vehicle's windshield. It can be attached or within the vehicle sun visor, or can be attached or within vehicle's dashboard, or attached to the windshield itself, or attached or within the vehicle back mirror. The information received is than processed within the HUD projector unit 100 to match its internal projector's image format. The image is than projected onto a visor reflector/lens 104 . The vehicle operator 102 can than view a superimposing of a virtual image 108 within a field-of-view (FOV) 110 on a front view looked through a windshield from an eye point 103 within the vehicle. The short range wireless link 114 may be Bluetooth, Wi-Fi, WiMax, NFC, UWB, Zigbee, or proprietary RF link such as RFWaves/Vishay, optical link, or a serial link such as USB, RS232, or similar. A remote Control 105 may be used to control the Operation of the Head Up Display (HUD) projector 100 .
[0042] Reference is now made to FIG. 2 which is a simplified functional block diagrams illustrating various implementations of the functionality of FIG. 1 . FIG. 2 shows a block diagram of one possible structure of a Wireless Head Up Display (HUD) 10 system of current invention. A HUD Projector unit 100 comprises of a Processor 200 , which manages HUD activities. The Processor unit 200 may be a simple MCU such as 8051, an ARM, a RISC or a DSP, or a special ASIC. The Processor unit 200 manages the communication with a wireless communicator 118 which may be a personal, or vehicle communicator such as a cellular phone, a portable, or mobile computer, a PDA, a GPS, or an infotainment (information-entertainment) system, a radio/TV receiver. A communication link 114 connects between the communicator 118 and the HUD Projector unit 100 . Such a communication link 114 of current invention is preferably a short-range wireless. Such a short-range wireless communication link 114 may be RF link such as Bluetooth, Wi-Fi, NFC, UWB, WiMax, Zigbee or proprietary RF such as RFWaves/Vishay, Chipcon, and Nordic. Alternative wireless link can be IR such as IrDA. A Communication interface 202 interfaces between the communicator 118 and the HUD processor 200 . In case a wireless link is used as the communication link 114 , the communication interface 202 is a wireless modem. An alternative embodiment of current invention is a wired link, which can be used as the communication link 114 . Such a wired link may be a USB, USB2Go, and serial link such as RS232, parallel link, optical, or a proprietary link.
[0043] Processor unit 200 receives images data to be displayed on the HUD. The Processor unit 200 processes this data and prepares it to match the projector display 212 parameters, so it would fit the projector display and the optical system, which comprises the HUD. In some cases, the processor 200 will also compute the adjustments that are needed to correct optical HUD system optical distortions due to lenses, reflectors, and light waves propagation. The image that is generated by the Processor unit 200 is transferred to the Projector display 212 . The Projector display 212 may be of a transparent LCD type. A light source and a diffuser 210 radiate light waves 216 through the Projector display 212 and via the optical adaptor 214 , that may be only a covering protecting transparent material, or may also has optical transfer function. The projected image light waves 220 are directed to the reflector visor unit 232 . The reflector visor unit 232 preferably can be of polycarbonate, a glass, a plastic, acrylic, or other transparent materials. Preferably the visor will be coated with a partly reflecting material, or colored, so it will function as a semi-transparent reflector. The reflector visor unit 232 preferably is shaped with optical gain such as parabolic, aspheric, or other shapes that would provide optical gain. Though it may also have no optical gain. The reflector visor unit 232 is preferably used as a reflecting lens of the projected image while being transparent to the images that are within the Field of view (FOV) of the vehicle operator's eyes 103 of FIG. 1 . Alternatively the reflector visor unit 232 may be a foil that is attached to the vehicle's windshield in order to prevent double image, in such implementation there is no optical gain at the visor unit 232 . The Visor reflector 232 may also be part of the windshield. It may be embedded within the windshield itself such by using optical materials such as DuPont's Butacite® wedged PVB interlayer. The projected images 108 that are reflected from the reflector visor unit 232 provides the vehicle's operator an augmented image of the images of the information as received from the Communicator 118 to be displayed overlaid with the images, which are within his FOV in front of the Vehicle.
[0044] In an alternative embodiment of current invention a Visor reflector 232 which can be attached to the vehicle by a Visor adaptor 230 . In such a case the Visor adaptor 230 enables adjustments of the Visor reflector 232 position and angels. Visor reflector 232 may also be detachable. So in case if an emergency situation while an external force which exceeds a certain amount which may endanger the vehicle operator, the Visor reflector 232 will be detached. In an alternative embodiment of current invention a Visor adaptor 230 holds the Visor reflector 232 in a folded position. Upon a defined event the Visor adaptor 230 may position the visor reflector 232 in an “active” position, which is within the FOV of the Vehicle operator. Such an event may be activation of the Communicator 118 such as activation of a cellular phone, receiving a cellular call, searching the address book, dialing or other central unit possible activations. Alternatively the Visor adaptor 230 can be activated by sound command, a remote control command, a touch of the Operator, or external communication event. Upon another defined event, the Visor adaptor 230 may put the Visor reflector 232 at an inactive position such as a folded position. Such events may be a termination of a cellular call. The speed of get in active position, or inactive position may be controlled by the Visor adaptor 230 providing optimized motion that will not be too sudden and not to slow. The HUD Projector unit 100 also comprise of power supply 222 , which powers the HUD Projector unit 200 . It may also comprise internal power source such as a battery, a rechargeable battery, and may also comprise of a connection to an external power source, such as a cigarette lighter socket. It may also comprise of solar cells for avoiding a connection of the HUD with the vehicle main power supply. It would be appreciated that using solar cells near the windshield would make the system easy to install and add-on existing vehicles.
[0045] The HUD Projector unit 100 may also comprise an analog, or digital, or RF interface unit 206 . The interface units 206 may be used for communication 107 with a remote control 105 for receiving Operators commands. The remote control 105 may consist of keys and a transmitter for transmitting commands upon pressing these keys. The communication 107 preferably is a wireless such as Bluetooth, Zigbee, or other short range wireless, alternatively it may be a wired communication such as a serial communication.
[0046] The HUD Projector unit 100 may also comprise a touch interface 224 which the may be used by the user to activate different functions of the HUD unit 10 . Such Touch interfaces 224 may be switches or other touch sensors.
[0047] In yet another embodiment of current invention the HUD Projector unit 100 may also comprise a sound interface 226 , which enables receiving sound commands from the vehicle operator, or generate sound. It may also has the capabilities of hands free speakerphone, enabling the user to listen to the sound received from the Communicator 118 and talk back from the sound interface 226 through the communication link 114 with the Communicator 118 . in such an alternative embodiment of current invention, the HUD Projector unit 100 is also used as a car kit with two way voice capabilities where the communication link 114 connects it to the Communicator 118 that may be such as a cellular phone.
[0048] In yet another embodiment of current invention the HUD Projector unit 100 may also comprise GPS receiver 223 , which enables receiving GPS signals, process and decode them and use that information for AGPS, or GPS location calculations. The processor 220 may than generate location related information to be presented to displayed on the Display Projector 212 . The HUD Projector unit 100 may receive Location Based information from the Communicator 118 through the communication link 114 . The Location Based information may be received by the Communicator 118 , through the long-range communication 120 from wireless location based services (LBS) such services may be such as navigation and driving directions, jamming avoidance and routing, and other LBS services. The location related information may be store and forward onto the HUD Projector unit 100 according to the GPS information, or be received in real time or pseudo real time, or any combination of store and forward and corrections upon need. It would be appreciate that current invention enables viewing GPS based services such as driving directions, while keeping “eyes on the road” by possibly having GPS capabilities within the HUD 10 , which is connected to a Communicator that may not have a built-in GPS.
[0049] In yet another embodiment of current invention the HUD Projector unit 100 may also comprise an optical interface 228 , which enables receiving visual commands from the vehicle operator. Such as identification of operator activations over virtual keypad that may be projected overlaid via the Visor reflector 232 . The optical interface 228 may also sense the light level within the operator FOV. That information is than processed by the HUD Processor unit 200 which than controls the level of radiation of the light source 210
[0050] Reference is now made to FIG. 3 , which differs from that of FIG. 2 in that whereas FIG. 2 shows a mobile HUD 10 that is connected to a wireless communicator of present invention, FIG. 3 shows implementation combined with a car kit 250 and or a headset 252 . A HUD Projector unit 100 may be connected to a central unit 118 such as a cellular phone, which may be also connected to car kit 250 . Alternatively, or in addition the Communicator 118 may be connected to a headset. Said connection preferably be RF wireless link, or may alternatively be wired.
[0051] FIG. 3 also shows yet another embodiment of the visor unit 104 of current invention. The visor unit 104 may also comprise an operator interface, which enables to operate variety of functionality of the HUD 10 , or to operate variety of functionality of the central unit 118 . Such preferred functionality of current invention is touch command interface 234 , a sound interface, or visual interface. Such a touch command interface may be a transparent touch activation layer that is attached to the reflector visor 232 . The operator interface can be located next to the visor adaptor, or in a separate unit, preferably within an easy reach of the operator.
[0052] Alternatively, or in addition the Operator can control the functionality of the HUD 10 by using, an easy to reach, remote control 105 with a communication link 107
[0053] It would be appreciated that operating a cellular phone, or mobile computer, a GPS unit, or radio, satellite of central unit 118 , without taking the eyes of the road would increase driving safety.
[0054] Reference is now made to FIG. 4 , which shows a block diagram of yet another embodiment of current invention of Head Up Display (HUD) 10 system showing another possible structure of current invention. A HUD Projector unit 100 may be connected by a car kit 250 with a communication link 115 . The car kit 250 may be connected to a Communicator 118 such as a cellular phone via a link 113 . car kit 250 may also be connected to another operator interface 254 , which may be connected wirelessly to the car kit 250 or directly to the wireless communicator 118 . The car kit communication link 115 is preferably be RF wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, WiMax, or may be wired connection such as a USB, USB2Go, serial link, parallel link, or a proprietary link.
[0055] The connection Link 113 between the Communicator 118 to the car kit 250 of current invention would preferably be a RF wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, UWB, WiMax. Alternatively it may be a wired connection such as a USB, USB2Go, serial link, parallel link, or a proprietary link.
[0056] Alternatively, the HUD 100 can be connected directly to the wireless communicator 118 preferably in wireless link 117 such as Bluetooth. At the same time the wireless communicator can also be connected directly to a car kit 250 , preferably in wireless link 113 such as Bluetooth, or using a wired link 113 .
[0057] FIG. 5 provides an illustration of yet another embodiment of current invention of Head Up Display (HUD) 10 system for providing augmented information 108 that is projected in front of a vehicle's operator 102 .
[0058] A long-range communicator device 118 such as a cellular phone, a wireless PDA, wireless computing apparatus, or a GPS, or an infotainment (information-entertainment) system is located within the vehicle cabinet, or embedded in the vehicle. The communicator device 118 is long-range wirelessly connected 120 with a wireless network. Such long-range wireless link 120 of current invention may be cellular network such as GSM, CDMA, GPRS, UMTS, WCDMA, 3G, 4G, or Wi-Fi, WiMax, satellite, GPS, satellite communication and other longer-range RF networks.
[0059] Information that is received through a communicator 118 , is transferred using a communication link 113 to a Car Kit 250 preferably wirelessly, or wired. The car kit 250 may be used for voice communication such as with central unit 118 , which may be a cellular phone. The Car Kit 250 may also be used for transferring information to the HUD projector 100 through a link 115 , which preferably a wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, alternatively it can be implemented over wire such as serial link. Such information may be cellular address book details, SMS, Caller-ID, GPS and other LBS information, and other network based information, or communicator's information. The link 115 may be bi-directional link, which passes information also from the HUD 100 to the communicator 118 . Such information may be Operators activations and commands, GPS information (in case a GPS is embedded within the HUD unit 100 ), or other types of data. Operator 102 commands may be provided by voice, or manual activations. Operator's Commands 253 may be applied directly to the communicator 118 . Operator's Commands 251 may be applied through the car kit 250 ; Operator's Commands 255 may be applied through the HUD 100 .
[0060] Connection Link 113 of current invention is preferably be wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, WiMax, or may be wired connection such as a USB, USB2Go, serial link, parallel link, or a proprietary link
[0061] The car kit 250 to HUD 10 connection Link 115 of current invention is preferably be wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, WiMax, or may be wired connection such as a USB, USB2Go, serial link, parallel link, or a proprietary link.
[0062] Alternatively, the car kit 250 to HUD projector unit 100 may be connection to the Communicator 118 via a direct link 117 . Such a link 117 of current invention is preferably be wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, WiMax, or may be wired connection such as a USB, USB2Go, serial link, parallel link, or a proprietary link.
[0063] A remote Control 105 may be used to control the Operation of the Head Up Display (HUD) projector 100 in such case it would preferably be connected to the HUD projector 100 via a wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, or proprietary RF. it may also control a car kit 250 directly via a wireless, or a wired link, alternatively it may control directly the communicator 118 .
[0064] Alternatively or in addition other devices and networks can be connected to the mobile HUD 10 . Such a network can be a vehicle wireless network 633 or devices that may be such as Bluetooth, Wi-Fi, Zigbee, NFC, UWB, WiMax, or other wireless networks and devices. The vehicle wireless network 633 can be connected via a link 631 to a communication interface 202 . A communication interface 202 may also include wires communication interfaces that possibly are linked 637 to other devices and networks 635 such as CAN serial communications bus.
[0065] The information received is than processed within the HUD projector unit 100 and than is projected onto a visor reflector 104 . The vehicle operator 102 can than view a superimposing a virtual image 108 within a field-of-view (FOV) on a front view looked through a windshield from an eye point 103 within the vehicle.
[0066] FIG. 7A provides an illustration of yet another embodiment of current invention of Head Up Display (HUD) 10 system for providing augmented information 108 that is projected in front of a vehicle operator 102 . A wireless communicator 118 as described in FIG. 5 may preferably be activated with voice activation such as Motorola car phone M800, or M900, or Nokia hand held voice activated cellular phone. Another preferable alternative embodiment of current invention is suing headset 252 that is connected through a link 257 to the communicator 118 . Preferably the link 257 is a wireless link such as Bluetooth, or other short-range wireless.
[0067] It would be appreciated that the combination of voice activation 253 with a mobile HUD 100 of current invention enables a safer way of using mobile devices while driving and enable the operator 102 to have his eyes on the road and his hands on the driving wheel. This combination for mobile phone application is trade marked as “Hands & Eyes Free™” mobile phone by the inventor.
[0068] A remote Control 105 may be used to control the operation of the Communicator 118 , and or the Head Up Display (HUD) projector 100 in such case it would preferably be connected via a wireless link such as Bluetooth, Wi-Fi, Zigbee, NFC, or proprietary RF. or a wired link.
[0069] Reference is now made to FIG. 7B , which illustrates another preferred embodiment of current invention. A wireless mobile HUD 10 , which consists of a long-range wireless link 120 such as a cellular link, WiMax, Wi-Fi, terrestrial and satellite links, proprietary RF link or other links. It would be appreciated that this embodiment of current invention would provide a cost effective HUD solution for displaying remote date and would enable many professional and consumer applications such as driving directions for mobile sells force traffic and weather notices, remote assignments and tasks, etc. one preferred embodiment of a mobile HUD 100 is a mobile HUD 10 that also consist of a mobile phone capabilities in addition of having a head up display capabilities. Preferably the mobile phone with HUD capabilities also has voice command capabilities 225 .
[0070] Another preferred embodiment is a mobile HUD has GPS capabilities and is connected through a long wireless link 120 to remote information center.
[0071] Reference is now made to FIG. 7C , which is a pictorial view of one of the preferred alternatives of current invention that is described in FIG. 5 , a mobile HUD 100 is connected near a vehicle windshield ( FIG. 7C shows how it can be attached to a sun visor). A mobile communicator 118 communicates ( FIG. 7C shows a mobile phone as an example for such communicator). The Mobile HUD 100 communicates with the mobile communicator 118 through a link 117 ( FIG. 7C shows a wireless link—preferably Bluetooth or alike); the Mobile HUD 100 can be controlled from a remote control 105 ( FIG. 7C shows a remote control that is attached on the steering wheel). The control is done through a link 255 ( FIG. 7C shows a wireless link, preferably RF link, alternatively it can also be a wired one). Alternatively the remote control 105 can control the mobile communicator 118 through a link 253 that may be wireless such as Bluetooth, or wired. The information from the mobile communicator 118 is transferred over the link 117 to the mobile HUD 100 processed and is displayed 108 through the visor 104 overlaid with the background images. Alternatively the user may use voice command 253 A to command the mobile communicator 118 . Yet another alternative that is shown in FIG. 7C is a headset 252 which the user may use to communicate with the mobile communicator 118 . this communication may be done through link 257 which is preferably a wireless link such as Bluetooth, or may be done with a wires headset, or a wires microphone.
[0072] Reference is now made to FIG. 7D , which is a pictorial view of one of yet another preferred alternatives of current invention that is described in FIG. 5 , a mobile HUD 100 is connected near a vehicle windshield ( FIG. 7C shows how it can be embedded within the sun visor). A mobile communicator 118 communicates ( FIG. 7C shows a mobile phone as an example for such communicator 118 ). The Mobile HUD 100 communicates with the mobile communicator 118 through a link 117 ( FIG. 7C shows a wireless link—preferably Bluetooth or alike). The mobile communicator is connected to a car kit 250 . The Mobile HUD 100 can be controlled from a remote control 105 ( FIG. 7C shows a remote control that is attached on the steering wheel). The control is done through a link 255 ( FIG. 7C shows a wireless link, preferably RF link, alternatively it can also be a wired one). Alternatively the remote control 105 can control the mobile communicator 118 , or through the car kit 250 , through a link 251 that may be wireless such as Bluetooth, or wired. The information from the mobile communicator is transferred over the link 117 to the mobile HUD 100 processed and is displayed 108 through the visor 104 overlaid with the background images. Alternatively the user may use voice command 253 A to command the mobile communicator 118 .
[0073] Reference is now made to FIG. 7E , which is a pictorial view of one of yet another preferred alternatives of current invention that is described in FIG. 7B , a mobile HUD 100 is connected near a vehicle windshield. The Mobile HUD 100 with long-range wireless capabilities communicates with the wireless network through a wireless link 120 . Preferably the wireless communicator is a mobile cellular phone. The Mobile HUD 100 preferably also have voice activation capabilities, so a user may communicate in an audible manner 255 A, alternatively or in addition a remote control 105 may communicate with the Mobile HUD 100 over a link 255 which is preferably a wireless link such as Bluetooth, or alike. The Mobile HUD 100 preferably also has GPS capabilities in addition of being a cellular phone. Alternatively it may be a wireless GPS that can be updated remotely.
[0074] The information from the mobile communicator is transferred over the link 117 to the mobile HUD 100 processed and is displayed 108 through the visor 104 overlaid with the background images.
[0075] Reference is now made to FIG. 10 . FIG. 10 provides an illustration of yet another embodiment of current invention of a wearable Head Up Display (HUD) 11 system for providing augmented information 108 that is projected in front of user 102 . It would be appreciated that Head Up Display (HUD) 11 of current invention is a wireless wearable HUD which enables displaying augmented information 108 on the move. Having a wireless wearable HUD frees the user from wiring that limits his movements.
[0076] A user wears A wireless wearable HUD Projector 100 using a HUD fastener 101 . A long-range communicator device 118 such as a cellular phone, a wireless PDA, an infotainment (information-entertainment) system, wireless computing apparatus, or a GPS is carried by the user, or is located closed by. The communicator device 118 is medium, or long-range wirelessly connected 120 with a wireless network. Such long-range wireless connection 120 of current invention may be cellular network such as GSM, CDMA, GPRS, UMTS, WCDMA, 3G, 4G, or local wireless networks such as Wi-Fi, UWB, NFC, WiMax, or satellite, GPS, and other longer-range RF networks.
[0077] Information, which the user 102 needs, is wirelessly transferred from the communicator device 118 using a communication link 117 to a wearable wireless HUD 100 .
[0078] The Connection Link 117 of current invention is preferably be RF wireless link such as Bluetooth, Wi-Fi, Zigbee, WiMax, UWB, NFC, or may be wired connection such as a USB, USB2Go, serial link, parallel link, or a proprietary link.
[0079] The wireless wearable HUD Projector 100 may also have built in GPS and or a compass, and or one or more axis gyros for location and angular orientation.
[0080] The information received is than processed within the HUD projector unit 100 and than is projected onto a visor reflector 104 . The user 102 can than view a superimposing a virtual image 108 within a field-of-view (FOV) on a front view looked through visor from an eye point.
[0081] FIG. 11 provides an illustration of yet another embodiment of current invention of a wearable Head Up Display (HUD) 11 system for providing augmented information 108 that is projected in front of user 102 . It would be appreciated that Head Up Display (HUD) 11 of current invention is a wearable wireless HUD that enables displaying augmented information 108 on the move without carrying any computing device. Having a wireless wearable HUD 11 also frees the user from wiring that limits his movements.
[0082] The integrated medium/long range wireless communication enables the user to access remote information and display it as an overlay of the images he sees in front of him. As a result the a wireless wearable HUD 11 enables a technician, or an engineer user to access remote maintenance and manuals information, a medical user may access remote medical information and or operation plans and other relevant information to what he needs while free his hands for other deeds.
[0083] A user wears A wireless wearable HUD Projector 100 using a HUD fastener 101 . The wireless wearable HUD Projector 100 also consists of a medium, or long-range wireless communicating means which enables wireless connectivity to a remote computer, or a remote network. Such communicating means may be a cellular modem, a wireless local area network modem, or a metropolitan wireless network modem.
[0084] Such long-range wireless connection 120 of current invention may be cellular network such as GSM, CDMA, GPRS, UMTS, WCDMA, 3 G, 4 G, or local wireless networks such as Wi-Fi, WiMax, NFC, UWB, or satellite, GPS, and other longer-range RF networks.
[0085] The wireless wearable HUD Projector 100 may also have built in GPS and or a compass, and or one or more axis gyros for location and angular orientation.
[0086] Information, which the user 102 needs, is wirelessly transferred from the remote computing device, or remote network using a communication link 120 to a wearable wireless HUD 100 .
[0087] The information received is than processed within the HUD projector unit 100 and than is projected onto a visor reflector 104 . The user 102 can than view a superimposing a virtual image 108 within a field-of-view (FOV) on a front view looked through visor from an eye point.
[0088] User may interact, or command the HUD, the remote computer, or remote network by voice commands, or by manual command 111 which are received by the HUD projector unit 100
[0089] Reference is now made to FIG. 12 . FIG. 12 is a block diagram of yet another embodiment of current invention of Wireless Head Up Display (HUD) 10 , or a wearable Wireless Head Up Display (HUD) 11 system showing another possible structure of current invention. A HUD Projector unit 100 may be connected to a portable computing, or communication apparatus 118 , using a RF wireless link 119 such as Wi-Fi, Bluetooth, Zigbee, NFC, UWB, WiMax, or other short-range or medium-range wireless. Alternatively or in addition it can be wirelessly connected through a wireless link 125 , to a wireless network 127 such as GSM, CDMA, DVB, GPRS, EDGE, WCDMA 3 G, 4 G, or other long range or cellular wireless networks. Alternatively or in addition it can be wirelessly connected through a wireless link 121 , to a wireless network 129 through a wireless access point 123 , or directly.
[0090] It would be appreciated that current embodiment of present invention would free the user from carrying any additional communication, or computing apparatus and the HUD 10 / 11 would become a wearable display and interaction apparatus enable him to use it hands free.
[0091] A portable computing, or communication apparatus 118 may be connected to Wireless Local Area Network 129 , or long range/cellular wireless network 127 .
[0092] Reference is now made to FIG. 13A, 13B 13 C, providing illustrations of yet another embodiments of current invention of wireless Head Up Display (HUD) 100 system for providing augmented information that is projected in front of a vehicle operator 102 .
[0093] Referring now to FIGS. 13A and 13B , A HUD projector unit 100 consists of communication means for receiving information to be displayed to an operator of a vehicle, An image is generated within a HUD projector 100 , the image is than projected onto a visor reflector 104 . The user 102 can than view a superimposing a virtual image 108 within a field-of-view (FOV) 110 on a front view looked through a windshield from an eye point within the vehicle.
[0094] While not using the HUD, the visor reflector 104 may be in an inactive position such as described in FIG. 13A . On demand, the visor reflector 104 may be placed into an active position such as described in FIG. 13B .
[0095] Putting the visor reflector 104 into an active position may be initiated by the user using voice command, or manual activation, or by the Head Up Display (HUD) projector unit 100 . That may be driven by internal cause, or by an external event or request, such external event may be receiving a cellular call, activation of the cellular phone, searching the address book within the cellular phone, activation of a GPS, or a computing apparatus.
[0096] A visor reflector 104 may be put in an inactive position using voice command, or manual command, such as a press of a button, or by the Head Up Display (HUD) projector unit 100 , that can be driven by an internal event, or by external event, or a request, such external event may be termination of a cellular call, time of not being used. Identifying an emergency situation will automatically place the visor reflector 104 in its inactive position.
[0097] A visor reflector 104 may be detachable, so while a severe situation occur, which may put the user in danger, such as vehicle accident, the visor reflector 104 may be decoupled from the its adaptor.
[0098] FIG. 14C shows a pop in and out version 175 of current invention that can be attached on the bottom side of the window windshield or on its upper side.
[0099] Preferably within a vehicle, a HUD projector 100 may be attached to, or built into a dashboard, a sun visor, or a back mirror. Alternatively it may be attached to the windshield, or the vehicles chassis.
[0100] Reference is now made to FIG. 14 , which illustrates a data input method and system of HUD 10 , which is operative and constructed in accordance with a yet another preferred embodiment of the present invention. Data input device preferably includes a projector 100 which projects an image 520 onto a HUD visor's reflector 104 the projected image is viewed by the user 102 as is appears in a distance away 108 . The projected image within the user's 102 Field Of View (FOV) of a HUD 108 may include two or more parts of images. One part may include an image of information and data 504 such as cell phone, or computing apparatuses information, or GPS related information. Another image part may include an input related image 506 , such as images of buttons. Images of the input means may be used as virtual buttons for entering data to the HUD.
[0101] One preferred embodiment of present invention is a image sensor such as a CCD image sensor scans 500 the data entry portion of HUD's visor 508 . The visual sensor may be located within the HUD unit 100 scanning the HUD visor's reflector 104 surface. A user may “activate” the data input means by approaching his finger 502 to the virtual button image of the HUD's visor 510 . The HUD's visual sensor passes these images to the HUD processor, which processes the presence of the finger next to the HUD's visor and its location. The processor than makes a decision of what button was activated. Once an activation of input means are identified, that data may be used for controlling the HUD operation and or for passing that data to a remote computing, or communicating apparatus. Such virtual data input means may be virtual keys for controlling a cellular phone, portable computer, a GPS, infotainment, or other apparatuses, which are connected to the HUD.
[0102] Additionally or alternatively the HUD input device of present invention may consist of touch screen. Preferably the touch screen will be a transparent touch screen. It may also be functional touch screen that its functionality may be control by software. Alternatively the input device may be capacitance, or inductive input means, acoustical presence and location means, or magnetic means that are attached or part of the HUD's visor 104 . A HUD System 10 with such input means may be wirelessly connected to a wireless communication apparatus, connected to a communication apparatus, GPS apparatus, or a computing device.
[0103] Additionally or alternatively the HUD input device keys may be located around or on the HUD visor reflector 104 for convenient use in case simple keys would be used.
[0104] A HUD System 10 with such input means may be installed within vehicles such as cars, airplanes, boats, and trains. Alternatively it can be used as a wearable HUD.
[0105] Such data entry keys may be wireless using RF technologies such as Bluetooth, Zigbee, NFC, or other short-range wireless.
[0106] Reference is now made to FIG. 15 , which illustrates a data input method and system of HUD 10 , which is operative and constructed in accordance with a yet another preferred embodiment of the present invention. A keypad 722 that is located near the vehicles operator's hands, preferably on the steering device 720 and is linked to the HUD projector 100 through link 726 , or and to the communication/computing/GPS apparatus 118 through link 728 . Preferably the input keypad 722 , such as described by 105 of FIG. 5 . would use wireless communication for link 726 , and or link 728 . The wireless link may be RF link such as Bluetooth, Zigbee, NFC, or other proprietary links such as RFWaves, Chipcon.
[0107] The input keypad 722 may be attached next to the driver and within a simple reach of the operator, or attached to the steering wheel 720 , be or be built in the steering wheel 720 . By pressing keys 724 user may remotely operate the communication/computing/GPS apparatus 118 , or the HUD operation itself. It would be appreciated that wireless keypad 722 of preferred embodiment of the present invention would enable vehicle operator to search through the address book of his cellular phone while pressing buttons 724 without taking the hands off the wheel and while looking at the phone numbers overlaid with the traffic in front of the car and without taking his eyes off the road.
[0108] The wireless input keypad 722 may be connected directly 728 to the cell phone, or GPS, or infotainment, or mobile computer 118 , or through the wireless link 726 of the HUD projector 100 .
[0109] Reference is now made to FIG. 16 , which illustrates a monochromatic HUD projector 801 , which is operative and constructed in accordance with a preferred embodiment of the present invention. An image is created at the LCD 810 . A light, preferably at a color of the monochromatic HUD color, or a white light, is generated by a light source 804 . Such a light source can be LED with an adequate color. The light is projected via a diffuser 802 , than through a LCD 810 . The LCD 810 is operating in the transitive mode. The LCD 810 functions as shutter in various shape and color. A light that is emitted 811 from the LCD 810 is reflected by the visor/lens/mirror 104 to the eye of the observer 103 . The image seen by the observer is magnified according to the visor optical gain and is placed virtually in front of the field of view and at distance 812 , which can be controlled by the distance to the image source or by the focal length of the visor. A lens 806 is coated by an optical coating 808 and is selectively reflective in the color, which the image is generated at the source LCD in it is transparent in other colors.
[0110] Reference is now made to FIG. 17A , which illustrates a multi-color HUD 803 , which is operative and constructed in accordance with a yet another preferred embodiment of the present invention. Image is created at the LCD 811 . A light, preferably a white light, is generated by a light source 804 . Such a light source can be LED. The light is projected via a diffuser 802 , then through the LCD 811 . The LCD 811 is operating in the transitive mode. The LCD 811 functions as shutter in various shape and color. The light emitted from the LCD 811 , is reflected by the visor/lens/mirror 104 to the eye of the observer 103 . The image seen by the observer is magnified and is placed virtually in front of the field of view and at distance, which can be controlled by the distance to the image source or by the focal length of the visor. The coating 807 , 808 , 809 on the lens 806 is selectively reflective in the different colors. Then different colors images are then generated on the color LCD 811 in a Time Division Multiplexing (TDM) and projected onto the visor 806 the relevant coating layer reflects the relevant image the observer eyes 103 then integrate the TDM images and creates a complete color image.
[0111] Reference is now made to FIG. 17B , which shows one possible flow diagram of a multi-color HUD 803 as described in FIG. 17A , which is operative and constructed in accordance with a yet another preferred embodiment of the present invention. Images in different colors such as Blue Green and red are generated at the color LCD 811 of FIG. 17A . They are created in a Time Division Multiplexing (TDM), The process may start 814 by generating the first color image 816 , such as a Blue image, and then another color image is generated 818 , such as a Green image and then another color image is generated 820 such as a Red image. Then the process repeats 822 with the first color. Tow or basic colors may be used. A full color Frame is accomplished by a projecting all the basic colors images. The color LCD resolution, size and quality, frame rate and LED illumination determines the image quality of the color HUD 803 .
[0112] Reference is now made to FIGS. 18A, 18B , 18 C which illustrates a multi-color HUD, which is operative and constructed in accordance with a yet another preferred embodiment of the present invention. A visor/lens is coated with a partial transparency and partially reflective coating. Several regions (three regions are shown in FIG. 18A as an example) of the red 830 , green 832 , and blue 834 , a low transparency (hi reflection) of light 836 will be implemented and at all other regions (wave lengths) there is a high transparency of corresponding light 838 . The over all transfer function of the lens is of a mirror or at the red, blue and green and as a transparent at other wavelengths (this is from the image in the field of view).
[0113] Reference is now made to FIG. 18B , which illustrates an image of the color LCD 840 where the dark blocks 842 all the white light from the light source. The various areas are transparent to specific colors, for example the rectangular figure of the LCD 848 is transparent to all colors but red. As a result any image within that rectangular area of the LCD will be viewed by the user in red while the LCD is projected in white or red lights. Similarly the figure “8” in the LCD 844 is transparent to all colors but green. The images of interest are in the colors, which the visor reflects.
[0114] Reference is now made to FIG. 18C , which illustrates a sample image of an augmented image 840 where various colors images from the LCD, are seen by the viewer. The specific images are reflected as they are in the same wavelength as the notches in the mirror/lens transfer function. The optics of the a-spherical lens/visor/mirror has an additional purpose of enlargement and placing the virtual image at a predefined distance such as infinity which suites a car or a pilot operator.
[0115] Reference is now made to FIGS. 20A and 20B , which are simplified partially pictorial functional block diagram illustrating a preferred embodiment of the present invention, including displaying of information that is received from a wireless network 117 and is preferably displayed by a mobile HUD 10 in accordance with a yet another preferred embodiment of the present invention.
[0116] It would be appreciated that current invention enables displaying WEB and other networks based information to operators of vehicles on the go and while enabling them to keep their eyes on the road. A mobile HUD 10 is connected to a mobile wireless communicator 118 such as a mobile phone. Alternatively a mobile wireless communicator with a built in HUD 600 can be used. The wireless mobile communicator 118 is connected to the wireless network 117 via a wireless link 120 . The wireless network 117 is also connected with a Wireless-to-WEB gateway 474 within the wireless service provider (Operator) 450 . Referring now to FIG. 20A , the Gateway 474 is connected to a Display Engine 470 that is located on the WEB and is connected 472 through the WEB to services Service Servers such 456 , 460 and 462 . These service Servers 456 , 460 and 462 provide services such as LBS (Location based services). The Display Engine 470 processes their Information before being sent back through the wireless network operator 450 and the wireless communicator 118 to be displayed on the mobile HUD 10 . FIG. 20B is another preferred implementation of current invention and where the service Servers such 456 , 460 and 462 are connected directly to the operator 450 and the display processing of fitting the information formats to formats that that are adequate for being displayed on the Mobile HUD 10 are performed within the service Servers such 456 , 460 and 462 services. Another preferred alterative of current invention (with is not shown) is that the formats conversion of the information received from the service Servers such 456 , 460 and 462 will be performed within the wireless service provider (Operator) 450 premises.
[0117] Reference is now made to FIG. 21 , which shows a simplified flow diagrams of a process of displaying information from wireless network 117 onto a wireless mobile HUD 10 in accordance with a yet another preferred embodiment of the present invention. A user 102 may initiate a process of retrieving and display remote information from a service Server 456 . The user 102 may submit a command 700 to the mobile HUD 10 . Alternatively user 102 may submit a command directly to the wireless communicator 118 . User may also register to specific services and upon certain conditions that system will automatically initiate the information deliver process without direct command by a user 102 . In case where the command is submitted to the mobile HUD 10 , the mobile HUD relays the request 704 to the wireless communicator 118 . As shown in FIG. 21 , the HUD 10 , and the wireless communicator 118 may be implemented as separate unites, or be embedded within one unit, which is a mobile communicator with a built in HUD 600 . Wireless communicator 118 wirelessly communicates the request 706 to the wireless network 127 . Through a gateway 474 to the Internet, the request is passed 716 via a Display engine 470 and through communication 720 to a service Server 456 of the requested information service. Alternative routing of the request may be applied such as a direct request 717 from the gateway 474 to the service Server 456 . The requested information is then provided by the service Server 456 through 722 to the display engine 470 . The display engine then processes that information and optimizes it for the Mobile HUD display 10 . It will typically perform format conversion, filtering, resizing and other possible processes. The reformatted information is passed 718 through the gateway 474 and via 714 to the wireless network 127 . The wireless network 127 communicates 710 the information through the mobile communicator 118 and through the link 706 to the mobile HUD 10 . The information is then presented 702 to the user 102 . It would be appreciated that according to current invention user 102 may interact with the information using vocal commands as described in FIG. 5 , or manual commands such as using a remote control.
[0118] Reference is now made to FIGS. 24A , and 24 B which are a block diagram of a mobile phone with built in mobile HUD 600 and a pictorial view of a mobile phone with built in mobile HUD 600 respectively in accordance with a yet another preferred embodiment of the present invention. A mobile phone with built in mobile HUD 600 consists of a HUD projector 602 that projects images that are generated by MCU 608 . A HUD visor 104 for displaying the projected images. It may also consist of HUD electro-mechanics 604 for possible mechanical operations of the HUD such as moving the visor in active position, or to its inactive position. A long-range wireless modem 606 communicates with long-range wireless networks such as cellular network, Wi-Fi, WiMax, or other long-range wireless networks. A processor MCU 608 manages the activities of mobile phone with built in mobile HUD 600 . it also may include a speakerphone capabilities as well as noise and echo cancellation 612 implemented in software or hardware. It may also include GPS receiver 610 supporting either AGPS, or GPS capabilities. It also includes a power supply 616 that may also consist of rechargeable batteries, external supply and optional solar power supply. It may include also I/O functions 617 such as keys, and or communication line such as serial links. The mobile phone with built in mobile HUD 600 may also include one or more short-range wireless modems 614 such as Bluetooth, 802.15.4 Zigbee, or others. These short-range wireless links may be use for communicating 630 with a remote control 620 or communicate 630 with other devices such as wireless headset, a Bluetooth device. A Bluetooth interface to the vehicle's network and others.
[0119] A remote control 620 may communicate with the mobile phone with built in mobile HUD 600 over wireless or wired link 630 . It typically has a processor MCU or ASIC 622 to manage its operation and keys 624 .
[0120] Referring now to FIG. 24B , which is a pictorial view of one possible implementation of a mobile phone with built in mobile HUD 600 that may be attached on the dashboard, or be embedded or attached in other locations within a vehicle and a possible remote control 620 .
[0121] Reference is now made to FIGS. 25A , B, C, D, E, F, G, H which are pictorial views and illustrates of some preferred implementations of a mobile HUD 10 or a mobile phone with a built in HUD 600 (for convenience the markings in the Figs are of 10 only) within a vehicle in accordance with a yet another preferred embodiment of the present invention.
[0122] FIG. 25A provides an illustration of yet another embodiment of current invention of mobile HUD 10 system where the mobile HUD projector unit 100 is located in the upper end of the vehicle windshield, preferably attached to the vehicle's sun visor 22 . A remote control 105 may be connected to the steering wheel 20 . In all FIG. 25 visor 104 may have active position and inactive position and mobile HUD 10 may move the visor 104 between these positions as explained in FIG. 13 A , B, C
[0123] In all FIG. 25 visor 104 is preferably part of the mobile HUD 10 , alternatively it may be attached to the windshield such as an optical foil, or is part if the windshield structure.
[0124] FIG. 25B provides a pictorial view of the mobile HUD 10 system as described in FIG. 25A . It also shows an example image of a direction arrow 108 that is projected by the mobile HUD projector 100 onto the visor 104 . The image is overlaid on the background image and within the driver's field of view. FIG. 25C provides an illustration of yet another embodiment of current invention of mobile HUD 10 system where the mobile HUD projector unit 10 is located within the vehicle's sun visor 22 . It would be appreciated that current invention would enable a vehicle's OEM to produce vehicles with built in mobile HUDs 10 .
[0125] FIG. 25D provides an illustration of yet another embodiment of current invention of mobile HUD 10 system where the mobile HUD projector unit 100 is located in the lower end of the vehicle windshield, preferably attached to the vehicle's dashboard 26 .
[0126] FIG. 25E provides a pictorial view of the mobile HUD 10 system as described in FIG. 25D . It also shows an example image of cellular call information 108 that is projected by the mobile HUD projector 100 onto the visor 104 .
[0127] FIG. 25F provides an illustration of yet another embodiment of current invention of mobile HUD 10 system where the mobile HUD projector unit 10 is located within the vehicle's dashboard 26 . It would be appreciated that current invention would enable a vehicle's OEM to produce vehicles with built in mobile HUDs 10 with the vehicle's dashboard 26 .
[0128] FIG. 25G provides an illustration of yet another embodiment of current invention of mobile HUD 10 system where the mobile HUD projector unit 100 is located near the vehicle back mirror 24 , preferably attached to the vehicle's back mirror 24 , alternatively it be part of the back mirror 24 . FIG. 25G provides an illustration of the mobile HUD unit 10 where the visor 104 is located on the lower end of the back mirror 24 .
[0129] FIG. 25G provides an illustration of the mobile HUD unit 10 where the visor 104 is located on the side end of the back mirror 24
[0130] FIG. 25H provides an illustration of the mobile HUD unit 10 where the visor 104 is located within the back mirror 24
[0131] It is appreciated that the mobile head up display (HUD) embodiments of the present invention are typically capable of enabling a user to view and possibly interact with mobile information while in a safer manner than today's solutions. Using present invention, a user may dial, receive a call, or watch cellular information such as SMS while keeping his eyes on the road and his hands on the steering wheel.
[0132] It is further appreciated that network based information services can be consumed by a user of present invention with reduced risks. Such services are navigation and routing information, and other location based services.
[0133] It is further appreciated that user of present invention would be able operate and view these and other services, applications and apparatuses such as infotainment systems. User may interact with said local and remote information service using voice commands, or using remote controls, enabling keeping his hands on the wheel
[0134] It is further appreciated that present invention technology enables significantly reducing costs of HUDs and therefore make it affordable to users thus increasing the driving safety while using cellular phones and other mobile apparatuses such as GPS.
[0135] Additionally, according to pre-determined criteria or specific requirement of a user information can be projected to the user of present invention without the need to operate it.
[0136] It is further appreciated that present invention enables using the invention embodiment as an add-on in any car without the need to have a special windshield and without the need to have a special dashboard.
[0137] It is further appreciated that present invention enables a user to read the projected information without changing his eyes focus to a different distance since the image is perceived to be in a distance ahead of his eyes.
[0138] It is further appreciated that present invention enables a user to seamlessly connect his cellular and mobile phone and other mobile device in a very simple manner using wireless communication that is available within his devices to the mobile HUD.
[0139] It is further appreciated that present invention enables a user to connect his mobile HUD to other information sources such as situation awareness, infotainment systems and vehicle systems using a wireless or other standard communications
[0140] It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and sub combinations of the various features described hereinabove as well as variations and modifications which would occur to persons skilled in the art upon reading the specification and which are not in the prior art.
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A mobile augments information system with capabilities of displaying information within field of view of the eyes a vehicle operator. The mobile augments information system includes a Head Up Display (HUD) apparatus consisting of a projector, a selectively reflecting visor and a HUD processing units. The Mobile HUD displays digital information that may be received from external sources such as a cellular phone, navigation system, automotive system, or remote information systems such as Location Based Services (LBS). The data may be received via a wireless link, or a wired link. The mobile HUD may be controlled locally, remotely by a vehicle operator using a wireless remote controller, or using voice commands. The mobile HUD system may also include internal information sources, such as a GPS receiver, or a cellular phone. The mobile augments information system can display textual and graphical information using monochrome or multicolor. Visor may be fixed or dynamically controlled.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the use of digital correlation receivers to measure the parameters of non-cooperative coherent or non-coherent emitters.
2. Brief Description of the Prior Art
Prior art approaches for measurement of relative phase, frequency and pulse repetition interval (PRI) for coherent emitters and the measurement of relative phase and frequency for a non-coherent emitter at the output of a correlation receiver use predominantly time domain techniques to characterize non-coherent, pulsed and asynchronous signals. Coherent processing in pulse doppler radar systems uses either time or frequency domain techniques to determine doppler shift with respect to a known frequency reference. Pulse compression in radar systems by both compressive and transform techniques achieves correlation with a known reference waveform. Compressive receivers and scanning receivers analyze the spectra of pulsed waveforms in receivers and spectrum analyzers. Fourier transform based receivers analyze frequency domain spectra. Correlation receivers in both time domain and frequency domain architectures measure time difference of arrival and differential doppler. Channelized receivers employ brute force frequency domain techniques to separate simultaneous signals by using a parallel bank of filters that provide frequency selectivity. If two signals are simultaneously present in a single channel, the channelizer may indicate the presence of multiple signals, but cannot measure truly simultaneous signals under all conditions of signal amplitude and relative time delay. An example of this is the presence of synchronized or nearly synchronized signals with harmonically related PRI values. For this condition, the channelizer will frequently fail to measure the parameters of either or both signals.
Instantaneous frequency measurement (IFM) receivers cannot measure the frequency of simultaneous signals. The IFM indicates the frequency of the largest signal in a simultaneous signal interception. An IFM receiver requires about 10 dB signal-to-noise (SNR) ratio at an intermediate frequency (IF) to properly indicate frequency.
Compressive receivers provide selectivity and multiple signal handling capability, but do not allow accurate measurements of PRI. These receivers permit estimation of pulse width at high SNR values, but have limited dynamic range and limited time resolution. Compressive receivers have a fixed time-bandwidth product for each design realization. This limits the performance of compressive receivers in environments that have a variety of signals. Compressive receivers lose sensitivity (SNR) when the signal does not completely fill the time aperture of the compressive receiver. Sensitivity loss is a function of duty cycle and can be calculated from the equation: -20★log (duty), where (duty) is the fractional ratio of the time the signal is present to the time aperture of the receiver.
Correlation receivers estimate time difference of arrival for signal detection in analog and digital realizations in a variety of applications. These receivers do not measure angle of arrival, PRI, pulse width or frequency in the digital domain using the methods described in the present application. If multiple signals are present in the same time aperture, the previously reported correlation processes cannot measure the signal parameters. The near zero delay terms of the correlation output contain information related to all the signals present in the receiver time aperture.
The performance of a time domain receiver is severely limited in the presence of multiple signals and in high density environments. This is because time domain receivers use some form of IFM to measure frequency and multiple time overlapping signals interfere with each other due to non-linear interactions within the IFM limiter. Typically, only one signal is measured at a time and the measurement is incorrect if two or more signals are present.
Fourier transform based receivers suffer sensitivity loss [-20★log(duty)] for signals that do not fill the time aperture of the receiver. This results in unacceptable sensitivity for low duty cycle signals.
Scanning receivers used in spectrum analyzers and EW systems provide a low probability of signal intercept due to the narrow instantaneous bandwidth. Multiple scans must be used to characterize moderate to low duty cycle signals.
SUMMARY OF THE INVENTION
The procedures used in accordance with the present invention differ from those previously published in the methods for measurement of relative phase, frequency and pulse repetition interval (PRI) for coherent emitters and the measurement of relative phase and frequency for a non-coherent emitter at the output of a correlation receiver. These methods provide a robust signal estimation capability.
The preferred embodiment in accordance with the present invention differs from known prior art approaches in the methods for determining the signal characteristics such as angle of arrival, pulse repetition interval, pulse width and measurement of modulation on the pulse for coherent, non-coherent, synchronous and asynchronous waveforms. The method disclosed in this application, used as a processing method for each channel of a channelizer, improves the capability to separate and measure simultaneous signals within a single channel. The method herein yields significant improvements in channel sensitivity, signal selectivity and signal characterization compared to current techniques and provides improved capability to measure simultaneous signal parameters by providing multiple frequency detection and multiple signal correlation. Significant increases in sensitivity, selectivity and parameter measurement accuracy are obtained over current IFM techniques. The methods in accordance with the present invention are programmable to permit a multiplicity of time-bandwidth product capabilities. This allows interception and characterization of signals with widely varying time-bandwidth product. The correlation receiver is more sensitive than the compressive receiver since the correlation process integrates over both the duration (time) and signal bandwidth of the unknown signal. The correlation approach permits more analysis flexibility than compressive receivers since the parameters of the analysis, such as time aperture and sample rate, are programmable. The method permits improvement of correlation receiver operation in multiple signal environments by making measurements at non-zero delay values in the correlation domain. Both time and frequency behavior of a signal at the output of a correlation receiver are measured. If multiple signals exist in the receiver time aperture, presorting in the frequency domain or separation in the correlation domain allows signal parameter measurement. Presorting in the frequency domain based upon angle of arrival (AOA) allows separation of signals even in the extreme case of harmonically related PRI. Harmonically related PRI values cannot be measured by any other known correlation receivers. If the signals have non-harmonically related PRI, the signals will separate at various delay values in the correlation domain, but separation in angle provides a more robust signal separation. If very high signal densities exist, the short time transform permits robust separation of signals in time, frequency and AOA. The present invention provides significantly more robust and flexible multiple signal separation than the prior art approaches. The preferred embodiment herein permits measurement of multiple signals using frequency and angle presorting. The processing approach provides superior sensitivity for all signals of interest with fast processing analogous to time domain processing at readily achievable data rates. SNR improvement of correlation for both moderate and very low duty cycle signals that may be non-coherent or coherent is provided. The programmable approach provides superior sensitivity performance to existing receivers. The present invention employs a variable time-bandwidth product receiver to significantly improve the probability of intercept of low and moderate duty cycle signals. Rapidly stepping the receiver across large frequency regions allows interception of continuous wave (CW) or pulsed waveforms with very high sensitivity and high probability of intercept.
Briefly, the processing methods in accordance with the present invention use a correlation receiver to improve the capability of present systems to determine parameters such as angles of arrival (AOA), frequency, pulse width, amplitude and pulse repetition interval from a radio frequency (RF) signal incident on a receiver with an array of antenna elements. The approach measures a time sequence of amplitude and phase data from an array of antenna elements and performs coherent digital signal processing to increase signal detectability and to determine parameters such as angles of arrival, frequency, pulse width, amplitude and pulse repetition interval from single or multiple radiating sources. The invention uses both short time aperture and long time aperture correlation for various classes of waveforms to optimize parameter measurement with a programmable digital signal processor.
In accordance with the present invention, novel methods are used for amplitude and phase calculation at the output of a correlation receiver to estimate signal parameters. The method allows reduction of receiver cost and complexity by using common components for angle of arrival as well as signal parameter measurement. This correlation processing method replaces intermediate frequency (IF) components such as logarithmic amplifiers, phase detectors, envelope detectors, scanning filters and associated oscillators, beam forming networks for monopulse receivers and compressive delay lines, thereby providing substantial cost savings and increased commonality between signal intercept and radar receiver application.
The method employs digital autocorrelation and crosscorrelation to determine these parameters. Autocorrelation allows the measurement of signal frequency by measurement of instantaneous signal phase. Crosscorrelation allows measurement of relative phase between two or more signals in two or more channels by measurement of instantaneous phase and by referencing the instantaneous phase to the autocorrelation function. The autocorrelation function and crosscorrelation function preserve relative amplitude and phase information of the signals in multiple channels. Measurement of relative amplitude and phase allows direction finding calculation for any current class of system that uses amplitude and/or phase to derive angle of arrival. Signal time and frequency measurement at the output of the correlation receiver result in robust characterization of the parameters of the signal. Digital calculations are superior to current analog or hybrid analog and digital methods because errors due to component aging, drift and temperature effect are easily prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a typical prior art multi-channel correlation receiver;
FIGS. 2a and 2b illustrate characteristics of typical continuous wave and pulsed signals respectively, measured at the output of an individual antenna element;
FIGS. 3a to 3c illustrate frequency domain characteristics for a typical continuous wave signal, a coherent pulsed signal and a non-coherent pulsed signal respectively;
FIG. 4 is a digital correlation processing diagram for a two channel receiver as used in accordance with the present invention;
FIGS. 5a to 5d show the methods for PRI, pulse width and intensity measurement for a coherent pulse train;
FIG. 6a is an examplary plot of a time domain pulse train;
FIG. 6b is an example of a coherent signal correlation domain "compressed" pulse; and
FIG. 6c is an example of a non-coherent correlation domain "compressed" pulse.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The correlation receiver measures the amplitude and phase of a radiated signal incident on an array of antenna elements. The preferred embodiment measures the relative amplitude and phase of an incoming signal between two or more channels in a receiver. The amplitude and/or phase between the signals received by each of the antenna elements determines the angle of arrival of the signal.
Referring first to FIG. 1, there is shown a receiver with multiple channels and an array of antenna elements. The amplitude and phase relationships between the output of antenna elements due to the incident angle of the signal are preserved in the receiver. For phase sensing monopulse or interferometry, the outputs of the elements are approximately equal in amplitude with a phase difference that is proportional to the angle of the incident signal off the centerline of the array. In amplitude sensing monopulse, the antenna elements share a common phase center but are steered in slightly different directions. The outputs of the antenna elements differ in amplitude but share the same phase. Each channel of the receiver includes an antenna element 110, an RF conversion stage 120 of standard type which converts the signal received from the antenna from an RF signal to an IF signal, an IF stage 130 of standard type which amplifies and conditions the IF signal received from the RF conversion stage so that it can be digitized and a coherent digital conversion stage 140 for converting the incoming analog signal to a digital signal. Digitization takes place in-phase and in quadrature form so that there are two elements of the signal for each incoming signal received from each channel, one being proportional to the sine of the input signal phase and the other being proportional to the cosine of the phase input signal. It follows that the analog to digital conversion at IF or at baseband generates a vector coherent with the stable phase reference (with coherent in-phase (I) and quadrature (Q) outputs). The receiver components 110 to 140 can be any radar, ECM or modern ESM receiver architecture. The digital correlation processor 150, a preferred embodiment of which is shown in FIG. 4, employs the parameter measurement methods disclosed hereinbelow and operates on the in-phase and quadrature outputs of the outputs of the coherent digital conversion stage.
FIGS. 2a and 2b illustrate characteristics of typical continuous wave (CW) and pulsed signals respectively, measured at the output of an individual antenna element 110. The preferred embodiment herein can process continuous wave or pulsed signals with no modulation or various types of amplitude, frequency and/or phase modulation. The time domain signals at this point in the processing chain may be low in amplitude and may be at or below the system thermal noise floor. FIGS. 2a and 2b show the important parameters of the time domain signals such as frequency, pulse width, amplitude and pulse repetition interval.
The time domain sequence from each antenna element is transformed to the frequency domain by techniques such as the Fourier transform. The time domain sequence may be weighted first to reduce spectral leakage in the frequency domain. The frequency domain transform improves the signal-to-noise ratio (and thus detectability) of signals that have bandwidth characteristics narrower than the sample frequency. The frequency domain transform also resolves narrow band signals and allows measurement of their frequency.
FIGS. 3a to 3c illustrate frequency domain characteristics for a typical continuous wave signal, a coherent pulsed signal and a non-coherent pulsed signal respectively, of interest. The continuous wave wave signal is very narrow band and exhibits the most signal-to-noise improvement. The non-coherent pulse train exhibits a sin(x)/(x) envelope centered at the carrier frequency, f 0 , with nulls at offsets of multiples of the reciprocal of the pulse width. The coherent pulse train is similar except that energy gathers at lines spaced by the PRF with the centralmost line at the carrier frequency.
Once in the frequency domain, the frequency characteristics of the signals may be measured directly. The angle of arrival is measured by comparing the phase and amplitude of signals from two or more channels as illustrated in FIG. 1. With the signals separated in amplitude, frequency and angle of arrival, individual radiating sources are resolved. The pulse width and the PRI (PRI=1/PRF) for coherent signals may be determined from the frequency domain data as shown in FIGS. 3a to 3c, however this measurement is very susceptible to noise and is not possible at low signal-to-noise ratios. Measurement of pulse width and PRI are more robust when accomplished by the correlation techniques described hereinbelow.
The average SNR improvement in a single filter at the output of the fast Fourier transform (FFT) processor for a coherent signal is: PGFFT (dB)=10★log(N)+20★log(duty), where PGFFT (dB) is average SNR improvement in a single filter in dB, N is the total number of samples processed in the FFT and N★duty is the number of signal samples processed in the FFT. The duty factor manifests itself into the SNR improvement in two ways, resulting in the square term in the equation 20★log(duty). First, since the duty cycle is always less than or equal to one, this term reduces the total amount of signal energy at the output of the FFT (for duty less than one). Second, if the signal does not exist in each time domain sample, its spectral energy at the output of the FFT will split into multiple filters, reducing the peak signal energy in a single filter.
The preferred embodiment of the digital correlation processor as shown in FIG. 4 uses a FFT based correlation calculation to provide estimates of pulse width, PRI, frequency, angle of arrival, intensity and signal modulation for coherent, non-coherent, synchronous or asynchronous signals. A presorting opertion may be performed between the initial Fourier transform and the fast correlation stage in the array processor 430 of the digital processing to remove CW and average value components of the signal. This permits processing of multiple, time-overlapped, pulsed, CW (or simple spread spectrum) chirped, and phase coded signals. Angle of arrival or frequency filtering separates multiple pulsed signals to permit processing of high duty cycle and low duty cycle signals that are highly synchronized in PRI and time of arrival.
Referring to FIG. 4, there is shown a digital correlation processing diagram for a two channel receiver. The two channels, ChA and ChB, (410) each provide complex valued, time domain, sampled and digitized data (variable sample rate determined by the information content of the signal) taken from a different one of the channels shown in FIG. 1, are transformed by hardware (FFTs 420a and 420b) designed to perform a variable and programmable length fast Fourier transform. This results in the transformation of the input time domain data to the frequency domain. The output complex data from FFT 420a is denoted as A and is multiplied in multiplier 440a by the output complex data from FFT 420a which is has been subjected to the complex conjugate operator (which is essentially taking the negative of the imaginary component of the data from FFT 420a) and is denoted as A*. This forms a magnitude at the output of the multiplier 440a. The signal from FFT 420a can also go to an array processor 430. The array processor 430 can select some subset of the signal A and feed that back to the multiplier 440a, this being used as a filter for the output of FFT 420a. Therefore, by selective processing at the array processor 430, which selection can be a region of frequency or an angle of interest, each of the signals is looked at in the array processor, a determination is made as to which signals come from a particular angle of arrival and a selection is made of those signals that come from an area or angle of interest and only those signals can be used as the multiplier in multlipler 440a. The output of the multiplier 440a is then subjected to an inverse fast Fourier transform in IFFT 450a which provides at its output the data in the form of a time series which contains the information to determine pulse repetition interval (PRI), pulse width (PW), intensity and angle. Magnitude and angle are preserved in this signal. This data is fed to the array processor 430 which, in conjunction with other signals input thereto as will be discussed hereinbelow, determines the detected PRI, frequency, PW, direction of arrival (DF), intensity and modulation from the received data.
The output of FFT 420a is also fed to multiplier 440b along with the output of FFT 420b which can be fed to the multiplier 440b directly or through the array processor 430 as shown in FIG. 4. The output complex data from FFT 420a is denoted as A and is multiplied in multiplier 440b by the output complex conjugate of the complex data from FFT 420b which is has been subjected to the complex conjugate operator (which is essentially taking the negative of the imaginary component of the data from FFT 420b) and is denoted as B*. This forms a magnitude at the output of the multiplier 440b. The output of the multiplier 440b is then subjected to an inverse fast Fourier tranform in IFFT 450b which provides at its output the data in the form of a time series which contains the information to determine PRI, PW, relative intensity and relative angle between the two channels. Magnitude and angle are preserved in this signal. This data is fed to the array processor 430 where it is filtered by multiplying it by a selected reference of signal B. This is a crosscorrelation in the same manner as the multiplication in multiplier 440a was an autocorrelation. Since both the angle and intensity of the signal are both present in the inputs to the array processor 430, the array processor contains the mathematics to calculate the direction finding (DF) information or angle of arrival. The mathematics are also present to calculate intensity so that the presence of the signal can be detected. The information in the PRI and PW and angle versus time information are used to calculate the presence of modulation on the signal. Since the angle of the signal is known, the frequency of the input signal can also be calculated.
The correlation processor of FIG. 4 provides both autocorrelation and crosscorrelation measurements to estimate the parameters and direction of arrival of signals. Signal parameters, such as PRI, pulse width, intensity, modulation, frequency and multiple signal presence are estimated with a single channel, using the autocorrelation output and frequency domain information from the first FFT stage. Estimation of direction of arrival requires two or more channels. The autocorrelation and crosscorrelation technique estimates the direction of arrival of multiple signals if the signals have different PRI values. Multi-channel receivers allow covariance estimation using the crosscorrelation calculations and high resolution angle (direction) of arrival measurements using known techniques for angle super resolution.
Further reviewing FIG. 4, which shows the signal processing flow for the processing approach covered by the preferred embodiment of the digital processing, though only two channel are shown and discussed, it should be understood that more than two channels can be present. As stated above, the two channels, ChA and ChB, each having complex valued, time domain, sampled and digitized data (variable sample rate determined by the information content of the signal) taken from a different one of the channels shown in FIG. 1, are transformed by hardware (FFTs 420a and 420b) designed to perform a variable and programmable length fast Fourier transform. This results in the transformation of the input time domain data to the frequency domain. The frequency domain data are separated by angle of arrival by comparing the difference in angle or magnitude and angle between the data in each channel for each frequency in the transformed output in an array processor 430. Signals with angles of arrival that are sufficiently different from each other are entered into separate arrays indexed by frequency. The newly formed arrays are magnitude and cross-product arrays that are formed by multiplying the complex conjugate of each frequency value for one of the channels by its complex amplitude (magnitude) and the complex amplitude of the adjacent channel (cross-product) in a multiplier therefor 440a and 440b. These arrays are transformed using a second stage inverse fast Fourier transform (IFFT) 450a and 450b to provide autocorrelation 460 output functions at the output of one of the IFFTs 450a and 450b and crosscorrelation 470 output functions at the output of the other one of the IFFTs 450a and 450b.
The input signal is sampled such that one or more complex (real and imaginary or in-phase and quadrature) sample is taken for each of two or more pulses or a signal wave form. Estimation of pulse width, PRI, intensity and frequency is achieved at either the autocorrelation 460 or crosscorrelation 470 outputs of the IFFTs 450a and 450b. Angle of arrival is calculated in array processor 430 from the amplitude and/or phase difference between the autocorrelation and the crosscorrelation outputs 460 and 470. Multiple channel receivers use the same processing shown for the two channel example in FIG. 4. Each channel pair is crosscorrelated in multiple channel implementations. Only one autocorrelation channel is required for a receiver with any number of channels.
FIGS. 5a to 5d illustrate the procedures required for signal pulse repetition interval (PRI), intensity and pulse width estimation of a single signal with a stable frequency (coherent pulse train) and PRI 510 as shown in FIG. 5a which would be an input signal to one of the channels with its Fourier transform shown in FIG. 5b. The signal PRI is determined by peak detecting the autocorrelation output 520 as shown in FIG. 5c or crosscorrelation output 530 as shown in FIG. 5d. The index of this peak (time or sample number) is related to the PRI of the signal. Multiple peaks will occur at multiples of the the PRI if more than two pulses are within the time window for the input time domain samples. The pulse width is the width of the correlation peak at half the peak amplitude of the correlation peak. Amplitude of the signal is estimated from the amplitude of the correlation peak and the pulse width. Frequency is estimated by computing the phase difference between successive samples of the autocorrelation function for values within the pulse width. The frequency, F, is given by the equation:
F=(φ(τ.sub.2)-φ(τ.sub.1))/2π=dφdτ
where φ(τ i ) is the phase of the autocorrelation function at delay i. Alternative estimation methods such as averaging or other filtering methods for the parameters above can be developed, but they all depend upon the fundamental relationships defined above.
The capabilities of the correlation receiver to measure frequency, angle of arrival and signal PRI are based upon mathematical properties of the correlation function and the behavior of the discrete correlation function.
Frequency measurement can be explained by considering a single signal in the autocorrelation calculation. If x(t)=A cos(ωt+φ), it can be shown that the autocorrelation function for the input function x(t) is: R(τ)=(A 2 /2)cos(ωτ). The autocorrelation function is independent of φ, but the instantaneous phase of the autocorrelation function is ωτ and dφ/dτ=ω=2πf, where f is the frequency of the signal. Therefore, the frequency is calculated at the output of the autocorrelation function, preferably in the processor 430, by taking the derivative of phase versus time (index) and calculating frequency from the relationship above.
Angle of arrival (AOA) estimation requires two or more channels. Angle of arrival is computed from the phase and/or amplitude difference between the crosscorrelation function and the autocorrelation function at one or more index or time value within the autocorrelation peak. A digital threshold may be applied to determine the number of points for angle calculation. An accurate estimate is obtained from a single index value determined by the peak detector (not shown but which would preferably be included in the array processor 430 of FIG. 4) used to estimate PRI. If more than one sample is used in the estimate, a more robust estimate in the presence of noise at low signal to noise ratios is obtained. For phase sensing systems, angle of arrival (AOA) is given by the equation: AOA=sin -1 (λx/2πd), where φ is the phase difference between the autocorrelation and crosscorrelation in radians, λ is the input signal wavelength in meters and d is the distance between the phase centers of the receive antennas in meters. This expression is evaluated at index values (times) which are at the peak or at several values near the peak of the autocorrelation function. It is important to reference the crosscorrelation value to the autocorrelation value since the relative phase, not absolute phase, is related to AOA. This relationship is derived in a manner similar to the derivation of the frequency measurement method previously discussed.
Processing for two channels containing simultaneously measured information from single or multiple sources is considered in the following derivation. When the signal in a first channel is given by the equation x 1 (t)=A 1 cos(ω 1 t+φ 1 ) and the signal in a second channel is given by the equation x 2 (t)=A 2 cos(ω 2 t+φ 2 ), the autocorrelation function discussed above for the signal in the first channel is arbitrarily chosen for this example as the reference signal as R 1 (τ)=(A 2 /2)cos(ω i τ) where |τ| is the relative correlation delay. The frequency may be estimated from the time derivative of phase. The crosscorrelation function taken between the two channels is given by: R 12 (τ)=<x 1 x 2 >. It can therefore be shown that R 12 (τ)=0 when ω 1 ≢ω 2 and R 12 (τ)=1/2A 1 A 2 cos(ω 1 τ+φ 2 -φ 1 ) for ω 1 =ω 2 ≢0. When the frequencies of the signals in the two channels are equal, the crosscorrelation function is non-zero and its amplitude is related to the amplitudes of the signals in the two channels. The autocorrelation signal is related to the amplitude of the signal in the reference channel. Since the channel amplitudes are preserved, sum/delta monopulse processing can be accomplished by processing the ratio of the crosscorrelation output to the autocorrelation output. For interferometric processing, phase information is required and is recovered from the phase of the crosscorrelation function referenced to the autocorrelation function phase. The instantaneous phase value of the autocorelation function given above for equal signal frequencies in the two channels is ω 1 τ+φ 2 -φ 1 . The derivative of this phase value with respect to time is ω 1 and the difference between the instantaneous phase of the crosscorrelation function and the autocorrelation function is the relative phase (φ 2 -φ 1 ) between the signals in the two channels. If both channels are received by a typical coherent-on-receive system, which incorporates a common stable reference for both channels, both frequency and phase information can be recovered from the measurements. The technique can be extended to multiple channel receiving systems to perform multiple phase center and multiple baseline interferometry.
If more than one signal is present in each of the receiver channels, phase and amplitude information can be recovered by processing multiple peaks of the correlation functions. This is possible if the signals have unique PRI values which are not harmonically related such that the PRI of one signal is not a harmonic of the PRI of another signal in the same receiver instantaneous bandwidth. This processing is possible due to the circular correlation properties of the discrete correlation function realized with the fast Fourier transform (FFT). The discrete correlation function is given by: ##EQU1## where Δt is the sample interval i is the time index
k is the delay index.
If the signals in the two channels are periodic with period PRI, the correlation function above will also be periodic with period PRI. If the two time functions are identical, the function z is the autocorrelation function. If the two time functions are from separate channels, the function z is the crosscorrelation function. The discrete correlation function may be calculated using the FFT by noting that the correlation function is the inverse transform of product of the complex conjugate of the Fourier coefficients of time samples x 1 and the Fourier coefficients of time samples x 2 by: ##EQU2## where X* (n/NΔt) is the complex conjugate of the Fourier transform of time samples x 1 . The correlation function is given by: ##EQU3## where IFFT is the inverse fast Fourier transform.
The technique applies to amplitude monopluse, amplitude and phase monopulse and phase interferometry. The processing preserves amplitude and phase information to permit calculation of direction of arrival from relative angle and relative amplitude using the autocorrelation and crosscorrelation methods described above.
If two signals are close to one another in angle and frequency, more than one signal may be in the correlation output since the angle and frequency sorting function may be too coarse to distinguish the two signals. If more than one signal is present in the autocorrelation and crosscorrelation function outputs, multiple peaks will occur at positions related to the PRI values for the individual signals. The terms in the correlation outputs near zero lag will contain information from all signals present in the input time window. To measure the parameters of multiple signals, the PRI values must not be harmonically related (integer multiples). If the signal PRIs are not harmonically related, the parameters of multiple signals can be measures using the peak detection methods described above. Each peak contains information related to the pulse width, PRI, intensity, frequency and AOA of the individual emitters.
A pulse train with a fixed frequency, fixed pulse width and constant PRI, as in pulse Doppler radars, is a coherent, periodic signal. The period of the signal is the PRI. The preferred embodiment disclosed herein provides a robust characterization of such signals if time samples are taken such that each pulse has at least one sample and more than one full PRI is sampled. Correlation can be used to characterize one or more signals which are non-harmonically related. For zero time lag between the signals, the value of the autocorrelation and crosscorrelation functions is related to the average power in the signals and noise present in the receiver. DC offsets and CW signals as well as harmonically related signals are removed by angle gating after the first FFT stage. Any non-harmonically related signals that remain will be characterized by the receiver as described hereinbelow.
As the magnitude of the delay between the signals is increased from zero, the value of the autocorrelation function decreases. When the magnitude of the delay is sufficient to ensure that no signal overlap occurs (i.e., |τ|>maximum pulse width for all signals present), the value of the autocorrelation function is determined by the noise in the channel or channels. When the magnitude of the delay is increased to a value such that |τ|≧(PRI -pw) min , where "min" indicates the signal for which the value in parentheses is minimum (PRI and pulse width belong to the same, unique frequency emitter), the correlation function will increase in value until |τ|=PRI min . For larger values of |τ|, the correlation value will decrease to zero at |τ`≡(PRI+pw) min . The correlation function will similarly peak at each successively larger PRI value, as demonstrated hereinabove with reference to FIG. 5, over the region defined by the pulse width for each signal as well as at each integer multiple of each of the PRI values for all the signals present at the IFFT input. If all the signal frequencies are different and the PRI values are unique and non-harmonically related, and the pulse widths are sufficiently small to prevent substantial signal overlap, unique characterizations will exist for each signal in the correlation calculation. If these conditions are not met, further adaptive processing for multiple overlapping signals can be accommodated by filtering the output of the first stage of FFT to separate signals in frequency, space (angle of arrival) or time of arrival dimensions.
If multiple signals can be distinguished in frequency or angle of arrival, separation in the frequency domain before magnitude (or cross product) and correlation calculation (IFFT) provides robust signal characterization, even if the signal PRI values are harmonically related. It is especially important to remove or separate average value (DC frequency component) and CW or very high duty cycle signals from low to moderate duty cycle signals to permit accurate measurement of lower duty cycle signals. This is accomplished by the angle and frequency presorting after the first Fourier transform stage or by appropriate receiver design before analog to digital conversion and is accomplished by known techniques for bandwidth control, such as channelization or bandwidth limitation and by real-time channel blanking for extremely complex, high signal density, environments.
The presence of some types of modulation on the signal can be estimated if sufficient signal to noise ratio exists. Comparisons of time domain measurement of signal frequency and pulse width to the frequency and pulse width at the output of the correlation process can be used to indicate the presence of modulation within the pulse or modulated CW. For a typical radar waveform with PSK or Barker modulation, the width of the modulation "chip" is the value obtained from the correlation process, while an envelope detector will measure the width of the total pulse. For example, if a 13 bit Barker code were used with a 200 nanosecond chip width, the total pulse width measured by an envelope detector would be 13 ★200=2600 nanoseconds. The correlation receiver would indicate an approximately 200 nanosecond pulse width. Comparison of the two results would provide potential information on the type of signal intercepted. Other modulation types, such as FM, BPSK and M-ary PSK provide characterization differences between correlation and time domain receivers that can be exploited to identify the signal type and modulation type for further classification and identification. Additionally, correlating the spectral width and shape at the output of the first FFT stage with the output of the correlation receiver provides further capability to classify signal modulation characteristics using "real time" autonomous systems.
The autocorrelation and crosscorrelation functions permit estimation of time difference of arrival beweeen two physically separated antennas and from two coherent sources, such as may occur in radar glint and signal multipath conditions. Time difference of arrival will result in a difference in the time index for the peaks of the signals in the autocorrelation and the crosscorrelation functions and a phase difference that is proportional to the delay. Multipath signals will experience more delay than direct path signals and will peak at larger time indices than direct path signals. Measurement of time difference of arrival and phase difference permits determination of angle of arrival unambiguously with a small number of antennas and receivers. For signals with spectral content, measurements of the derivative of phase with respect to frequency in the Fourier transform allows measurement of delay if measurement of angle and delay in the correlation output is insufficient to provide unambiguous AOA determination.
The correlation receiver generates the autocorrelation and crosscorrelation functions of the outputs of two separate antennas that view the same signals from different perspectives. As an example, if the antenna received three pulses of a pulse train as shown in FIG. 6a, the sampled time domain envelope of this signal that contains N samples could appear as shown in FIG. 6a. The envelope of the signal in the correlation domain will contain five triangular wave forms which contain 2N samples similar to those shown in FIG. 6b. The correlation domain is much like the output of a pulse compressor. The peak of the signal at t=0 contains all the energy of the pulse train "compressed" to maximize the signal to noise ratio (SNR). The time sidelobes (or PRI peaks) of this "compressed pulse" may have lower amplitude and SNR than the peak at zero delay, but they reveal important information about the signal that is being analyzed.
In the frequency domain, the pulse train energy is spread over the spectral lines that are characteristic of its Fourier transform. The Fourier transform produces spectral lines (coefficients), the amplitude of which indicates the amount of energy at these frequencies contained in the signal. If the input pulse train consists of a series of coherent phase pulses, as those created by a pulse Doppler radar using a TWT transmitter, the spectrum is well behaved and the signal correlates from pulse to pulse. The spacing between the spectral lines is equal to the pulse repetition frequency. If the phase from pulse to pulse is random, like a pulse train that is generated by a non-coherent radar with a magnetron transmitter, the spectral lines are irregularly spaced. This spectrum is very similar to the spectrum of a phase coded pulse train. The correlation domain "compressed pulse" will appear like the wave form as shown in FIG. 6c. The time sidelobes (correlation peaks) may be suppressed in amplitude.
The Fourier transform exploits periodicity in waveforms. When the waveform is a coherent pulse train, the periodicity is observed in the frequency domain by equally spaced spectral lines. The transform from the frequency domain to the correlation domain employs an inverse Fourier transform. The periodicity of the "wave form" yields a well behaved waveform in the correlation domain (see FIG. 6b). The spectrum that results from the non-coherent phase pulse train will have unequal spacing between its spectral lines and this will result in a waveform in the correlation domain that could have lower energy in the correlation peaks that are at delays greater than zero. However, it is important to observe that for either pulse train, the correlation peak at t=0 contains all the energy associated with the signal analyzed. This has two important implications. First, by reducing the length of time period analyzed the energy around t=0 can be used to analyze the amplitude, frequency and phase of the signal. Second, if multiple signal types are segregated before the transform to the correlation domain, the peak around t=0 will contain only the signal to be analyzed. Angle of arrival can be determined since only the energy from one source is present. Since the peak at t=0 also contains the average power in the wave form for autocorrelation, use of adjacent delay values (delay 1 and delay 2 relative to zero are the second and third samples in the correlation output) is recommended in the preferred embodiment short transform receiver mode.
The present procedure can be applied to a wide variety of wave forms, including coherent, non-coherent, synchronous and asynchronous processing to provide significant improvement in SNR and signal characterization over currently employed techniques. It can be realized in real time applications as well as in post processing applications to permit robust signal characterization and identification. The technique uses programmable sample rates, times and adaptive processing for separation of signals in benign or complex environments. Processing sample rates and time windows are adjusted to the signal environment based upon measured or expected signal characteristics.
For non-coherent signals, high density environments and very low duty cycle signals, the correlation process is used to measure intensity, partial pulse width, angle of arrival and frequency of signals present within a short FFT and correlation time window. The first two samples after the sample at zero delay are used to estimate the partial parameters of the signal. Further processing of the short time transform and correlation data of each successive short aperture time correlation provides approximate measurement of PRI and complete domain signal correlation.
Though the invention has been described with reference to a specific preferred embodiment thereof, many variations and modifications will immediately become apparent to those skilled in the art. It is therefore the intention that the appended claims be interpreted as broadly as possible in view of the prior art to include all such variations and modifications.
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The parameters of a digital signal are extracted by the application of autocorrelation and crosscorrelation techniques to effectively measure the frequency and time behavior of a digital signal. The method employs digital autocorrelation and crosscorrelation to determine these parameters. Autocorrelation allows the measurement of signal frequency by measurement of instantaneous signal phase. Crosscorrelation allows measurement of relative phase between two or more signals in two or more channels by measurement of instantaneous phase and by referencing the instantaneous phase to the autocorrelation function. The autocorrelation function and crosscorrelation function preserve relative amplitude and phase. Measurement of relative amplitude and phase allows direction finding calculation for any current class of system that uses amplitude and/or phase to derive angle or arrival. Signal time and frequency measurement at the output of a correlation receiver result in robust characterization of the parameters of the signal. Digital calculations are superior to current analog or hybrid analog and digital methods because errors due to component aging, drift and temperature effects are easily prevented.
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BACKGROUND
[0001] Ear buds provide a function of sound replication, i.e., they act as speakers, in addition to providing, in many cases, some level of hearing protection or isolation. However, products currently available in the marketplace are of a generic nature and in most cases do not fit the average wearer adequately, if at all. The resulting functionality of generic ear buds is thus poor, and the sound quality often fails to meet consumer expectations.
[0002] Another prevalent problem associated with ear bud style products is that once placed in the ear and sealed in the ear canal, with the volume set to a safe and comfortable level, external sounds become muffled or inaudible, leaving the user unable to safely navigate their surroundings. With a poor fit, this problem is somewhat mitigated. However, in this case, the level of ambient sound will have a direct affect on the amount of volume needed for the user to be able to hear the intended sound source.
BRIEF SUMMARY OF THE INVENTION
[0003] This patent application is for a unique communication management device that allows the user to control his/her sound environment both in and outside the ear. The device overcomes all previous shortcomings encountered by emergency first responders, military, SWAT, firefighters, police, sports enthusiasts, musicians, as well as other users, to overcome usage limitations encountered with single application headsets.
[0004] Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0005] FIG. 1 is a diagram of an ear piece set according to an embodiment of the invention;
[0006] FIG. 2 is a reduced schematic diagram of the ear piece set according to FIG. 1 ;
[0007] FIG. 3 is a diagram of a further ear piece set according to an embodiment of the invention; and
[0008] FIG. 4 is a reduced schematic diagram of the ear piece set according to FIG. 3 .
DETAILED DESCRIPTION OF THE INVENTION
[0009] Consider a person standing in a subway with their friends, wearing ear buds. The volume of the audio device may be set to a level such that the person is able to hear music playing through their ear buds, but they can also hear the conversation of their friends. Increasing the volume in the ear buds will block the conversation from being heard, allowing the user to focus on the music. Now consider that as a subway train arrives, greatly increasing the ambient noise level, the volume to which the user had increased the volume to block the conversation is no longer enough. Thus, the volume through the ear buds must be increased further to enable the music to be heard above the sound of the train. As the volume increases to overcome ambient noise, the user begins to damage their hearing in a permanent, irreversible and yet preventable manner.
[0010] Not only can poorly fitting ear buds cause hearing damage in this way, but they may also create a hazardous condition for the user and those around them. For example, consider an emergency first responder at an accident scene wearing a radio connected to their ears via a headset. In a noisy accident scene, the user has to turn the radio volume up excessively to hear critical transmissions. However, the user is now hindered or disabled from hearing sounds around them such as cries for help, people speaking, warning bells and sirens, and other such external environmental sounds. Recognizing this, a skilled user may periodically take off their headset or reduce the volume. However, this action creates the risk of missing critical transmissions. In other words, in order to listen for pleas for help or hear verbal orders, the user must either take out the headset, or turn the volume down so low that they are now isolated from hearing radio signals from team members and management personnel. Thus, the ill-fitting ear wear forces the user to choose between two unsatisfactory and unsafe alternatives.
[0011] Further consider the case of a SWAT or police officer situated on a stakeout, wearing a radio earpiece in order to hear command communications. Moreover, the user would like to monitor subtle ambient noises for sounds of danger, but is prevented by the ear piece from hearing such sounds. Moreover, if the user's weapon or other nearby weapon is suddenly discharged, there is a high probability of hearing damage. The user is forced to choose between hearing tactical commands, protecting their hearing from sudden noise, or listening for danger.
[0012] Similarly, a user on a motorcycle may decide to listen to your music via a headset, which may also protect their hearing by isolating them from wind noise. However, the user is now not able to communicate with a fellow rider on the same machine or a nearby machine, and is also less able to hear nearby important environmental noises such as a siren, a dog barking, or police commands.
[0013] The invention overcomes the many shortcomings of current systems and allows the user to:
[0014] 1. Manage the sound in their ear,
[0015] 2. Manage the sound outside the ear,
[0016] 3. Communicate via a “no wire” Bluetooth device,
[0017] 4. Speak clearly via a microphone,
[0018] 5. Prevent sudden noises (like gun shots, siren blasts, etc.) by instantly shutting off noise as it occurs, and
[0019] 6. Restore normal hearing when the noise subsides to safe levels.
[0020] In general use, the device increase user safety by reducing the amount of volume required to listen to a source, allowing the wearer to detect the ambient sounds all around them, and be safe and provide hearing protection in environments where sudden noise protection is needed.
[0021] A traditional speaker requires air to turn an electronic signal into a sound wave for the transfer of energy to the bones in the ear to be heard. This is because the speaker creates a sound wave in the air, and both air and a certain amount of air movement are required for such a wave to propagate. In contrast, the audio micro transducer used within the invention does not require air to generate sound energy. The invention thus enables placement of the transducer into a custom mold of an individual's ear to completely block harmful ambient sound. This provides a sufficient reduction of sound to protect a wearer up to levels of, for example, 110 dBa.
[0022] The following combination of components in an embodiment of the invention, integral to the device, will provide the wearer the ability to hear outside noise:
[0023] 1. Ambient Noise Microphone
[0024] When powered ON, will pick up the outside noise and transfer that information to the inner ear canal.
[0025] 2. Volume Control
[0026] This mini pot will allow the wearer to increase or decrease to an off position, the amount of volume needed to reproduce sound for that individual's amount of hearing loss, if any.
[0027] 3. Compression Circuit
[0028] This micro processor measures the amount of sound being picked up by the ambient noise microphone, measures the frequency and amplitude of that sound, and controls how much of the sound is transferred to the transducer to supply sound to the wearer. The ambient noise microphone will, within 1.1 to 1.3 milliseconds, measure the sound pressure level of monitored noise and determine how much compression is needed, and regulate how much sound is passed to the transducer for sound delivered into the ear canal. This device is also programmable to receive information provided by the wearer to help in amplification of reduced frequencies due to a wearer hearing loss. For example, older users may suffer deterioration in their ability to perceive higher frequency sounds.
[0029] 4. Audio transducer
[0030] This device will receive the signal from the compression circuit and will reproduce the sound supplied and transfer sound to the inner ear canal.
[0031] 5. Battery Door and Battery
[0032] This supplies the power source to the inside of the earpiece and is the power source location for the ambient noise microphone, compression circuit. In an embodiment of the invention, this is also the location for programming the compression circuit for response calculations and frequency amplification.
[0033] The device according to an embodiment of the invention may also include a number of optional components including:
[0034] A. On/Off Switch
[0035] This switch will energize the compression circuit, which will allow the wearer to choose to have the ambient noise microphone on or off, both on or both off. In an embodiment of the invention, each ear piece is independent and can be selected or deselected independently.
[0036] B. Bone Conduction Microphone
[0037] This additional component will pick up the vibration of sound from the vocal cords in the inner ear canal and transmit those vibrations through a microphone to a communication device or cell phone. This will allow the wearer to engage in transmit, receive and ambient noise applications. In an exemplary consumer application, this feature is useful for cell phone conversation, while allowing the user to hear outside information and remain safe and protected from loud noise environment.
[0038] An exemplary military and first responder application would encompass the use of 2 way radio communications and silent radio transmissions to enable mission critical communications without interference or detection.
[0039] C. Cord Control
[0040] A water proof control location, useful for police, fire rescue, first responder and military, is also provided in an embodiment of the invention. This application will allow all of the controls to be removed from the earpiece and placed onto a wired control housing, primarily to provide the ability to protect from moisture or submersion into fluid, but also to increase size of the controls and enhance the ability to use controls with a gloved hand.
[0041] The attached drawings show exemplary devices and configurations within embodiments of the invention for the sake of clarification. Referring to FIG. 1 , there is shown an ear piece set according to an embodiment of the invention. The illustrated set includes a volume control as well as an on/off switch. One or more battery doors are provided. In addition, an external source cable communicates an electrical reproduction of the intended sound to each earpiece. One or both ear pieces may further comprise one or more optional ports for an ambient noise microphone. The external source cable may terminate in a suitable jack or plug, such as, for example, a 3.5 mm 90 degree stereo plug.
[0042] FIG. 2 shows a reduced schematic of the set shown in FIG. 1 . In the view of FIG. 2 , the elements described above may be seen. In addition, this view shows an ambient noise microphone, an ambient noise volume control, a crossover network, a compression circuit, an ambient noise transducer, and a sound transducer for outside source. In an embodiment of the invention, the crossover network enables coordination between the ambient noise and the supplied external source noise.
[0043] FIG. 3 shows a set similar to that shown in FIG. 1 , but also including an optional bone conduction microphone according to an embodiment of the invention. The optional bone conduction microphone allows the user's speech to be airlessly detected and converted to an electrical signal for transmission.
[0044] FIG. 4 shows a reduced schematic of the set shown in FIG. 3 . The view of FIG. 4 shows the elements associated with FIG. 3 and also shows several additional elements such as an ambient noise microphone, an ambient noise volume control, a crossover network, a compression circuit, an ambient noise transducer, and a sound transducer for outside source.
[0045] It will be appreciated that the foregoing systems and implementations are merely examples. However, it is contemplated that other implementations of the invention may differ in detail from foregoing examples. As noted earlier, all references to the invention are intended to reference the particular example of the invention being discussed at that point and are not intended to imply any limitation as to the scope of the invention more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the invention entirely unless otherwise indicated.
[0046] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
[0047] Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.
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A unique communication management device allows the user to control his/her sound environment both in and outside the ear. The device overcomes previous shortcomings encountered by emergency first responders, military, SWAT, firefighters, police, sports enthusiasts, musicians, as well as other users, with respect to single application headsets by utilizing a combination of an ambient noise microphone, volume control, compression circuit, and audio transducer. In an embodiment of the invention, the device also includes independent left and right on/off switches and one or more bone conduction microphones.
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BACKGROUND OF THE INVENTION
[0001] This invention relates to an electric motor and more particularly to a flat, brush type electric motor having a compact construction and high power output.
[0002] A flat motor with brushes includes a rotor and a stator which rotate with respect to each other. Generally the rotor includes a rotary shaft, a plurality of flat coil elements fixed at circumferential positions radially around the rotary shaft. A commutator is also fixed to the rotary shaft and connected to the ends of each flat coil element. The stator includes a plurality of magnets facing and sandwiching the flat coil elements, and brushes in sliding contact with the commutator.
[0003] In order to produce high torque with this type of flat motor, the gap between the magnets sandwiching and facing the flat coil elements has to be reduced to minimize the magnetic gap. Thus when using flat coil elements with the same number of turns in the radial direction, thinner flat coil elements are more preferable.
[0004] In the case of a flat motor with brushes, adjacent flat coil elements are disposed so as to overlap to some degree with each other as viewed in the direction of the rotary shaft as shown in Japanese Published Application JP-A-Hei 6-217502, so that the respective flat coil elements are continuously energized through the brushes via the commutator.
[0005] This could be avoided with the use of a brushless flat motor, since respective flat coil elements do not have to be disposed so as to overlap with each other, because their rotational positions are detected by a sensor to control energization. However in some instances this is a rather more expensive machine.
[0006] In the conventional flat motor with brushes, however, the flat coil elements must be disposed so as to overlap with each other as noted above. This requires an increased gap between the magnets to clear the overlapping parts of the flat coil elements. Therefore, the magnetic gap is increased, which reduces the effective magnetic flux, and accordingly the amount of torque produced.
[0007] It is, therefore, a principal object of the invention to provide a high output flat electrical motor of the brush type.
SUMMARY OF THE INVENTION
[0008] A first feature of this invention is adapted to be embodied in an electric machine and more particularly to a flat, brush type electric machine having a compact construction. The machine comprising a plurality of flat coil elements disposed between a plurality of facing, circumferentially spaced permanent magnets. The coil elements having generally trapezoidal or pie shape with the adjacent edges thereof closely spaced without overlapping each other. A commutator fixed relative to the coils and has segments to which respective coil winding ends are electrically connected. Brushes are in sliding contact with the segments for transferring electrical energy with the coils upon relative rotation between the coils and the permanent magnets.
[0009] Another feature of the invention is adapted too be embodied in a machine as set forth in the preceding paragraph and wherein the axial thickness of the coil elements is generally tapered in a radial direction and the adjacent faces of the permanent magnets are tapered in a like manner to maintain a like gap between the coils and the permanent magnets in a radial direction.
[0010] Another feature of the invention is adapted to be embodied in an electrical machine as described in the first paragraph of this section wherein the coil windings are connected to the commutator segments in such a way so that there are always two air gaps between connected segments at all times during relative rotation to avoid voltage loss.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a side elevational view of an electric motor constructed in accordance with an embodiment of the invention and showing the various elements in outline.
[0012] FIG. 2 is a cross sectional view taken along the line 2 - 2 in FIG. 1 .
[0013] FIG. 3 is a side elevational view showing the shape of a flat coil element employed in the motor.
[0014] FIG. 4 is a perspective view of the flat coil element.
[0015] FIG. 5 is a sectional views taken along the lines 5 - 5 of FIG. 4 .
[0016] FIG. 6 is a sectional view taken along the lines 6 - 6 of FIG. 4 .
[0017] FIG. 7 is a perspective view, in part similar to FIG. 4 and shows another embodiment of flat coil element in accordance with the present invention.
[0018] FIG. 8 is a developed view showing the connection of coils of the embodiment of FIGS. 1-6 .
[0019] FIGS. 9A-9C are developed views in part similar to FIG. 8 is a illustrates the connections made during successive stages of rotation during operation of a motor with the connection of coils as shown in FIG. 8 .
[0020] FIGS. 10A-10C are developed views of coils, in part similar to FIGS. 9A-9C , and show the current flow during successive stages of rotation of another embodiment.
[0021] FIGS. 11A-11C are developed views of coils, in part similar to FIGS. 9A-9C and 10 A- 10 C, and show the current flow during successive stages of rotation of yet another embodiment.
[0022] FIGS. 12A-12C are developed views of coils, in part similar to FIGS. 9A-9C , 10 A- 10 C and 11 A- 11 C and show the current flow during successive stages of rotation of yet another embodiment.
[0023] FIG. 13 is a developed view of another example of coils of the present invention.
[0024] FIG. 14 is a developed view of another example of coils of the present invention.
[0025] FIG. 15 is a developed view of another example of coils of the present invention.
[0026] FIGS. 16A-16C are developed views of coils, in part similar to FIGS. 9A-9C , 10 A- 10 C, 11 A- 11 C and 12 A- 12 C and show the current flow during successive stages of rotation of yet another embodiment.
[0027] FIGS. 17A-17C are developed views of coils, in part similar to FIGS. 9A-9C , 10 A- 10 C, 11 A- 11 C, 12 A- 12 C and 16 A- 16 C, and show the current flow during successive stages of rotation of yet another embodiment.
[0028] FIG. 18 is a developed view, in part similar to FIG. 10 but showing still another embodiment.
[0029] FIG. 19 is a developed view, in part similar to FIG. 15 but showing still another embodiment.
[0030] FIGS. 20A-20C are developed views of coils, in part similar to FIGS. 9A-9C , 10 A- 10 C, 11 A- 11 C, 12 A- 12 C, 16 A- 16 C and 17 A- 17 C, and show the current flow during successive stages of rotation of yet another embodiment.
[0031] FIGS. 21A-21C are developed views of coils, in part similar to FIGS. 9A-9C , 10 A- 10 C, 11 A- 11 C, 12 A- 12 C, 16 A- 16 C, 17 A- 17 C and 20 A- 20 C and show the current flow during successive stages of rotation of a still further embodiment.
DETAILED DESCRIPTION
[0032] Referring now in detail to the drawings and initially to FIGS. 1 and 2 , a flat motor, indicated generally at 21 and constructed in accordance with the invention is comprised of a rotor, indicated generally at 22 and a stator, indicated generally at 23 .
[0033] The rotor 22 is comprised of a rotary shaft 24 that carries a rotary plate 25 . A plurality of (twelve in this embodiment) flat coil elements 26 are secured at radially spaced locations around the outer circumference of the rotary plate 25 . Each flat coil element 26 is molded with resin and suitably secured to the outer circumference of the rotary plate 25 .
[0034] The windings of the coil elements 26 are electrically connected in manners to be described to a commutator 27 fixed to the rotary shaft 24 to rotate together with the rotary plate 25 . The outer circumferential surface of the commutator 27 is divided into a plurality of segments 27 a corresponding in number to the number of coil elements 26 . The respective segments 27 a are connected with winding ends of the respective flat coil elements 26 , as will be described shortly and as aforenoted.
[0035] Continuing to refer to FIGS. 1 and 2 , the stator 23 is formed with a motor case 28 for covering the entire motor 21 including the rotor 22 . A plurality of pairs of (eight pairs in this example) permanent magnets 29 are fixed to opposing inner surfaces of the motor case 28 in closely spaced facing relation to the flat coil elements 26 . A plurality of brushes 31 (four in this embodiment) are carried in sliding contact with the outer circumferential surface of the commutator 27 in any suitable manner. The rotary shaft 24 of the rotor 22 is rotatably supported by the motor case 28 via bearings 32 .
[0036] As shown in the drawings and particularly FIG. 1 , the flat coil elements 26 , are of a generally pie shaped pieces arranged radially around the outer circumference of the rotary shaft 24 , are configured such that adjacent edges of the coil elements are closely juxtaposed without overlapping with each other. Also as has been noted, the winding ends of each flat coil element 26 are connected to respective segments 27 a of the commutator 27 as will be described later.
[0037] As best seen in FIGS. 3 and 4 , each flat coil element 26 is generally formed in the shape of a triangle (or a trapezoid) that is wider on the outer circumferential side thereof. The coil is shaped such that both oblique sides of the flat coil element 26 coincide with radial directions emanating from the rotational axis of the rotary shaft 24 . If one oblique side deviates from a radial direction by θ while the other oblique side coincides with a radial direction as shown in this figure, only a component of electric current corresponding to cos θ contributes to torque generation. Thus the electric current applied to the coil element 26 is not effectively utilized. Therefore, it is preferred to shape each flat coil element 26 with sides being disposed so that the angle is reduced to zero and adjacent edges are closely spaced without overlapping each other so that the electric current produces high torque.
[0038] Referring now to FIGS. 5 and 6 it will be seen that the thickness, that is the axial extent, of the flat coil element 26 is greater on the inner circumferential side, shown in FIG. 5 , than on the inner circumferential side, shown in FIG. 6 . Correspondingly, the gap between the magnets 29 and 29 sandwiching and facing the flat coil elements 26 can be tapered so as to be smaller on the outer circumferential side. The scale of FIG. 2 is, however, so small that this condition can not be illustrated in this view. This can reduce the magnetic gap to produce high torque. It also permits a minimum gap circumferentially between adjacent coils as shown in FIG. 1 without overlapping.
[0039] Referring now to FIG. 7 , this shows the appearance of a coil according to another embodiment of the present invention. In this embodiment, the flat coil element 26 is formed by winding a band-like iron member 33 generally into the shape of a triangle. An insulating film 34 may be interposed between layers of the winding iron member 33 . The surface of the iron member 33 may be copper-plated to increase the electrical conductivity. Instead of using the insulating film 34 , the surface of the iron member 33 may be coated with an insulating coating. When the iron member 33 is used as winding, as described, the winding itself also serves as a yoke for forming magnetic fields between the magnets 29 and 29 (see FIGS. 1 and 2 ). This can further reduce the magnetic gap between the magnets to produce high torque. These coils 26 can be connected as described next by reference to FIGS. 8 and 9 A- 9 C. When the coils with such a connection structure are energized, electric currents which flow through adjacent windings of the coil elements flow in the same direction, which can reduce energy loss and prevent phase shift.
[0040] Referring now to FIG. 8 , this is a developed view, showing an example of connection of the flat motor shown in FIGS. 1 and 2 and having coil windings as shown in FIGS. 4-6 or FIG. 7 . This example of connection is based on the case where the number of magnets 29 “m”=8, the number of coil elements 26 “t”=12, the number of segments 7 a of the commutator 27 “s”=24, and the number of brushes 31 “b”=4. The coil elements 26 and the commutator 27 are components of the rotor 22 , and the magnets 29 and the brushes 31 , which will be described later in more detail by reference to FIGS. 9A-9C , are components of the stator 23 .
[0041] The winding ends of the respective coil elements 26 are connected to specific of the segments 27 a of the commutator 27 . Certain of the respective segments 27 a are connected with each other by means of wiring 14 . The mutual connection between the segments 27 a permits a reduction in the number of brushes. The coil elements 26 and the commutator 27 made up of segments 27 a are fixed to the rotary shaft 24 , as shown in FIGS. 1 and 2 , to constitute the rotor 22 . The brushes 31 on the stator 23 side successively into contact with the segments 27 a, which rotate along with the rotation of the rotor 22 , to energize the respective coil elements 26 to drive the motor.
[0042] As shown in FIGS. 8 and 9 A- 9 C, both winding ends of each of the twelve coil elements 26 cross each other, cross one winding end of an adjacent coil element, and are connected to the segments 27 a. The number of segments “s” is twice the number of coil elements “t,” with two segments 27 a provided immediately below each coil element 26 . The winding ends of each coil element 26 are connected to either a distant one of the two segments immediately below it, or a distant one of the two segments immediately below an adjacent coil element. The coil elements connected to the segments immediately below themselves and those connected to the segments immediately below adjacent segments are disposed alternately. In other words, every fourth two segments are connected to a coil element and every fourth two other interposed segments are not connected to an coil segment thus forming a series of coils energized in a specific direction, as will be noted. In this way, as shown in the drawing, out of the twenty four segments, twelve segments, namely segments #3, 4, 7, 8, 11, 12, 15, 16, 19, 20, 23, and 24, are used to connect the twelve coil elements 26 to form a series of coils. Such connection can form the series of coils such that adjacent coil elements 26 are energized alternately in opposite directions to each other between positive and negative. This allows electric currents which flow through adjacent windings of the coil elements to flow in the same direction, which can reduce energy loss and prevent phase shift.
[0043] The wiring 35 connects the twenty four segments 27 a with each other such that each segment 27 a is connected to a segment 27 a located twelve segments away from it. In other words, the segments #1 and #13, segments #2 and #14, . . . , and segments #12 and #24 are connected. As shown in these figures and as previously described, the respective coil elements 26 are energized through the brushes 31 , which are disposed appropriately, to cause the rotor to rotate. The dotted line shows coil elements 26 being switched over and thus not energized.
[0044] Referring now to FIGS. 10A-10C these views are in part similar to FIGS. 9A-9C and show another embodiment of coil connection structure according to the invention. This embodiment is shown as an example where the number of magnets 29 “m”=4, the number of coil elements 26 “t”=6, the number of segments 27 a of the commutator 27 “s”=12, and the number of brushes 31 “b”=4. FIGS. 9A-9C show the states where the brushes 31 sequentially move relatively rightward as seen in the figures by half the segment, along with the rotation of the rotor.
[0045] The six flat coil elements 26 are disposed facing the four magnets 29 . Both winding ends of each coil element 26 are connected to segments located in predetermined positional relation, out of the twelve segments 27 a (#1-#12). As shown in the figures, both winding ends of each coil element 26 cross each other, cross one winding end of an adjacent coil, and are connected to the segments 27 a. The number of segments “s” is twice the number of coil elements “t,” with two segments 27 a provided immediately below each coil element 26 .
[0046] The winding ends of a coil element 26 are connected to either a distant one of the two segments immediately below it, or a distant one of the two segments immediately below an adjacent coil element. The coil elements connected to the segments immediately below themselves and those connected to the segments immediately below adjacent segments are disposed alternately. That is, every fourth two segments are connected to a coil element and every fourth two other interposing segments are not connected to a coil segment to form a series of coils. In this way, as shown in the drawing, out of the twelve segments, six segments, namely #1, 2, 5, 6, 9, and 10, are used to connect the six coil elements 26 to form a series of coils. The series of coils are energized through the brushes 31 as indicated by the arrows, which causes adjacent coil elements to be energized in opposite directions to each other between positive and negative, and parallel adjacent windings of the coil elements 26 to be energized in the same direction. This eliminates phase shift.
[0047] FIGS. 10A-10C show the states where the brushes 31 sequentially move relatively rightward in the drawing by half the segment, along with the rotation of the rotor. As shown in the drawing, the interval between adjacent brushes 31 is large enough to include two gaps between the segments 27 a. Such allowance for two or more gaps between the segments 27 a, which serve as an insulating region to improve the insulation performance and the ability to withstand a greater voltage without leakage.
[0048] FIGS. 11A-11C illustrate another embodiment of the present invention. In this embodiment, six segments that are not used in the foregoing example of FIGS. 10A-10C (#3, 4, 7, 8, 11, 12) are used to form coil elements 26 of another series of coils, as shown in FIG. 11B , in overlapping relation with the series of FIG. 15A and as shown in FIG. 11C . That is, six segments (#1, 2, 5, 6, 9, and 10) are used in the same manner as in FIGS. 10A-10C to form a series of coils as shown in FIG. 11A , and then the remaining six segments (#3, 4, 7, 8, 11, and 12) are used to form another series of coils over the former series of coils as shown in FIG. 11B . This allows all the segments 27 a to be used uniformly as shown in FIG. 11C , which can increase the use efficiency of the segments to produce stable high output. In addition, since the brushes 31 experience substantially constant frictional resistance in association with sliding contact during rotation, deterioration of the brushes can be inhibited to extend the service life of the brushes. Incidentally, in FIG. 11C where the series of coils of FIG. 11A and those of FIG. 11B are overlapped with each other, the circuit of coils of FIG. 11B are indicated by the dot dashed line in FIG. 11C .
[0049] Referring now to FIGS. 12A-12C these views are in part similar to FIGS. 9A-9C and 10 A- 10 C and show another embodiment of coil connection structure according to the invention. In this embodiment shows how the width of the brushes 31 can be increased and hence the gap between the brushes 31 is accordingly reduced. In this embodiment, the interval between the brushes includes only one gap between the segments in the position of FIG. 12B ), but includes two gaps between the segments in the positions of FIGS. 12A and 12C . By setting the interval between the brushes 31 so as to include two or more gaps between the segments 27 a at at least one position during rotation, the average interval between the brushes is increased to obtain a sufficiently high to prevent voltage leakage. This reduces constraints on the width of the brushes and increases the degree of freedom in design.
[0050] FIG. 13 is a developed view of still another embodiment of the present invention. In this embodiment, the number of magnets “m”=6, the number of coil elements “t”=8, the number of segments “s”=16, and the number of brushes “b”=6. As in the embodiment of FIGS. 10A-10C , 11 A- 11 C and 12 A- 12 C both winding ends of each coil elements 26 cross each other, cross one winding end of an adjacent coil element, and are connected to the segments 27 a. The number of segments “s” is twice the number of coil elements “t,” with two segments 27 a provided immediately below each coil element 26 . The winding ends of each coil element 26 are connected to either a distant one of the two segments immediately below it, or a distant one of the two segments immediately below an adjacent coil element 26 .
[0051] The coil elements connected to the segments immediately below themselves and those connected to the segments immediately below adjacent segments are disposed alternately. In this way, as shown in the drawing, out of the sixteen segments, eight segments, namely #1, 2, 5, 6, 9, 10, 13, and 14, are used to connect the eight coil elements 26 . The series of coils are energized through the brushes 31 as indicated by the arrows, which causes adjacent coil elements to be energized in opposite directions to each other between positive and negative, and parallel adjacent windings of the coil elements 26 to be energized in the same direction. This eliminates phase shift.
[0052] In cases where m=6 as described above, as in the foregoing example of FIGS. 11A-11C , the unused segments (#3, 4, 7, 8, 11, 12, 15, and 16) may be used to form another series of coils in overlapping relation.
[0053] FIG. 14 is a developed view of still another embodiment of the present invention. In this embodiment, the number of magnets “m”=8, the number of coil elements “t”=10, the number of segments “s”=20, and the number of brushes “b”=8.
[0054] As in the foregoing embodiments of FIGS. 10A-10C , 11 A- 11 C, 12 A- 12 C and 13 , both winding ends of each coil element 26 cross each other, cross one winding end of an adjacent coil element, and are connected to the segments 27 a. The number of segments “s” is twice the number of coil elements “t,” with two segments 27 a provided immediately below each coil element 26 . The winding ends of each coil element 26 are connected to either a distant one of the two segments immediately below it, or a distant one of the two segments immediately below an adjacent coil element 26 . The coil elements connected to the segments immediately below themselves and those connected to the segments immediately below adjacent segments are disposed alternately. In this way, as shown in the drawing, ten segments, namely #1, 2, 5, 6, 9, 10, 13, 14, 17, and 18, are used to connect the ten coil elements 10 to form a series of coils.
[0055] The series of coils are energized through the brushes 31 as indicated by the arrows, which causes adjacent coil elements to be energized in opposite directions to each other between positive and negative, and parallel adjacent windings of the coil elements 26 to be energized in the same direction. This eliminates phase shift.
[0056] In addition, as in cases where m=8 as described above, as in the foregoing example of FIGS. 11A-11C and 13 , the ten unused segments (#3, 4, 7, 8, 11, 12, 15, 16, 19, and 20) may be used to form another series of coils in overlapping relation.
[0057] FIG. 15 is a developed view of still another embodiment of the present invention. In this embodiment, three coil elements 26 are provided in a space where six coil elements 26 could be accommodated, with a blank space for one coil element present between respective adjacent coil elements 26 . The number of segments “s” is 12. Two coil oppositely wound elements 26 a and 26 b are formed in overlapping relation on each of three coil element spaces, out of the six coil element spaces. Then, out of the twelve segments, six segments 27 a are used for connection to form the series of coils.
[0058] As shown in the figure, one winding end of each of the coil elements 26 a and 26 b formed in overlapping relation, cross each other and are connected two adjacent segments 27 a. The other winding ends of the other coil element 26 a and 26 b are led away from each other and connected to distant segments 27 a. As in the foregoing embodiments having double windings, every fourth two segments 27 a are connected to a coil element and every fourth two other interposing segments 27 a are not connected to a coil segment.
[0059] The current flow through the coil elements 26 a and 26 b during rotation through successive steps is shown in FIGS. 16A-16C similar to those of FIGS. 11A-11C where the brushes sequentially move relatively rightward in the drawing by half the segment, along with the rotation of the rotor. The arrows indicate the direction of energization from the brushes 31 .
[0060] FIGS. 17A-17C shows the case where the three coil element spaces and six segments that are not used in the embodiment of FIG. 15 are used to form another series of coils in the same configuration as in FIG. 15 . FIG. 17A is the same as FIG. 15 , with two coil elements 26 a and 26 b formed in respective coil element spaces. FIG. 17B shows another series of coils in the same configuration as in FIG. 17A , formed in the other coil element spaces using the other segments. Two coil elements 26 c and 26 d formed in the respective coil element spaces are connected to form a series of coils. The components of FIGS. 17A and 17B are overlapped with each other as shown in FIG. 17C .
[0061] FIGS. 18, 19 , 20 A- 20 C and 21 A- 21 C show the coil connection construction of four still other embodiments of the present invention. In these embodiments, the segments are mutually connected to reduce the number of brushes (to four or less).
[0062] FIG. 18 shows the case where each segment is connected to a segment located six segments away from it in the same coil winding structure as in the foregoing embodiment of FIG. 13 .
[0063] FIG. 19 shows the case where each segment is connected to a segment located six segments away from it in the same coil winding structure as in the foregoing embodiment of FIG. 15 .
[0064] In FIGS. 18 and 19 are shown examples with six coil element spaces and twelve segments. However, the present invention is not limited thereto, but applicable to cases where the number of coil element spaces is t and the number of segments is 2t, by connecting each segment to a segment located t segments away from it.
[0065] FIGS. 20A-20C are the counterparts of previously described embodiment of FIGS. 10A-10C but in the embodiment of FIG. 18 where the number of brushes is two, showing the states where the brushes sequentially move relatively rightward in the drawing by half the segment, along with the rotation of the rotor. Because of this similarity, further description of this embodiment is believed unnecessary to permit those skilled in the art to understand the construction and operation
[0066] FIGS. 21A-21C are the counterparts of previously described embodiment of FIGS. 10A-10C but in the embodiment of FIG. 19 where the number of brushes is four, showing the states where the brushes sequentially move relatively rightward in the drawing by half the segment, along with the rotation of the rotor.
[0067] Thus it should be readily apparent from the foregoing descriptions that by mutually connecting the segments as described where the number of brushes is 2, 3, or 4, phase shift can be eliminated and the voltage can be increased without leakage. Also although the present invention is applicable to a flat motor with brushes for installation in a small space, such as a radiator fan for an automobile. Of course those skilled in the art will readily understand that the described embodiments are only exemplary of forms that the invention may take and that various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims.
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A flat electrical machine having high efficiency by configuring the coil windings so that adjacent edges thereof are closely adjacent, extend radially and do not overlap circumferentially. The thickness of the windings varies along their length and thee facing magnets are also tapered to maintain a constant and small air gap. In addition the coli winding ends are connected to commutator segments to maintain at least two air gaps between connected segments at all times to avoid voltage leakage.
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CROSS-REFERENCE TO RELATED APPLICATION
The invention herein is an improvement over the invention set forth in Applicant's copending application, Ser. No. 612,907, now U.S. Pat. No. 4,003,698 filed Sept. 12, 1975, in the name of Robert W. Snyder and entitled "Product and Method of Printing Carpet".
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is primarily directed to a technique for printing carpet, and more particularly, to a printing technique that uses sublimable dyes and uses the carpet backing as the transfer carrier for the sublimable dyes.
2. Description of the Prior Art
U.S. Pat. No. 3,782,896 discloses it is old to use transfer printing operations to print carpet designs.
Transfer printing through the use of sublimable dyes is an old art. Normally, the dye is carried on a transfer carrier or sheet, and the transfer carrier is placed up against the surface to be dyed. Through the use of heat and pressure, the sublimable dyes are converted to a vapor stage and transferred to the surface of a material adjacent the transfer carrier. The transfer carrier is then usually discarded. When one would attempt to transfer print heavy fabrics, such as carpet, then vacuum action would be required to attempt to secure some dye penetration into the fabric.
The inventive technique herein is the utilization of the transfer carrier as a portion of the finished product. Herein, specifically, the transfer carrier is used as the conventional backing for a carpet backing that has tufted thereinto the face carpet yarns which will be subsequently dyed by the sublimable dyes on the transfer carrier. The sublimable dyes are transferred through the face carpet yarns by the use of a vacuum operation.
SUMMARY OF THE INVENTION
A conventional carpet backing is provided with a pattern printed thereon through the use of inks containing sublimable dyes. After the inks have had an opportunity to dry, conventional yarn is tufted into the carpet backing to form the ultimate carpet product composed of a backing and tufted face yarn. Heat and vacuum are then used, and this causes the sublimable dyes to change to a vapor phase and be transferred from the carpet backing to the carpet face yarn. There then results a product which is composed of a carpet backing and face fiber yarns containing a decorative pattern thereon.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic drawing of the process herein, and
FIG. 2 is a cross-sectional view of the product of the invention herein.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The process herein is carried out by basically the following steps. A conventional carpet backing or scrim material, which preferably is porous in nature, is provided with a design printed thereon by a conventional Zimmer printer, utilizing inks containing sublimable dyes. Printing can be carried out by any commercially available printer, as long as it places the different inks in position in register. The printed carpet backing is then permitted to air dry. A conventional carpet yarn is tufted into the carpet backing by conventional tufting machinery. The pile or loops or face fiber yarns of the finished tufted yarn product will be preferably on the same side of the carpet backing as was the printed design containing sublimable dyes. The carpet backing with the tufted yarns is then subjected to heat and vacuum action whereby the pattern printed on the carpet backing is transferred from the carpet backing and fully developed throughout the height of the pile of the face yarns. There is then provided a carpet product which has a backing and yarn tufted into the face thereof with the yarn being dyed in a selected pattern.
In one specific example of the invention, conventional jute carpet backing with a 19 × 19 count is utilized. The 19 × 19 count is the number of yarns in the warp and woof direction. The aforesaid jute weighs approximately 6 ounces per square yard (203 grams per square meter). This material is run across a Zimmer printer and printed with conventional inks containing sublimable dyes. Specifically, the dyes being used are Latyl Cerise NSN, C.I. Disperse No. Red 60, C.I. Constitution No. 60756; Latyl Violet 2R, C.I. Disperse No. Violet 28, C.I. Constitution No. 61102; and Acetamine Yellow CG, C.I. Disperse No. Yellow 3, C.I. Constitution No. 11855. The design printed on the jute may be any type of aesthetic design, and after it is printed on the jute with the aforesaid sublimable dyes, it is permitted to dry. Nylon 66 yarn, Dupont Type 846, 1300 denier, bulk continuous filament is then tufted into the jute using a 5/64 gauge (0.2 cm), 12 tufts per inch to produce a 1/8 inch (0.3 cm) pile level loop carpet weighing 13 ounces per square yard (441 grams per square meter). This then yields a product similar to FIG. 2 wherein the carpet scrim 2 is provided with a design 4 and tufted yarn 6. The tufted yarns have their pile looped construction on the side of the carpet backing 2, which is the same side of the carpet backing 2 which has the printed design 4.
The product is then placed in a vacuum transfer device, such as that disclosed in British Pat. No. 1,363,145. Any type of apparatus may be utilized which will apply heat to the transfer sheet to vaporize the dye and then pull the dye by vacuum action from the transfer sheet through the carpet face fibers. The carpet would be positioned with the vacuum source on the face fiber side of the carpet so that the dye would be drawn from the back of the carpet through the face fiber yarns to the vacuum source.
The above-described product was placed in an apparatus similar to that of British Pat. No. 1,363,145 and was subjected to 205° C. dry heat for 31/2 minutes at 28 inches mercury vacuum. During this time, the pattern 4 which was printed on the jute with sublimable dyes is transferred and fully developed throughout the height of the pile 6. The print is brightly colored with a soft, diffused appearance.
In addition to using jute as the backing material, the invention can be carried out with woven glass fibers or any other type of conventional carpet backing material which will be stable at approximately 200° C. to 220° C. In addition to using Nylon 66 as the carpet face yarn, the invention can be carried out using Nylon 6, acrylic and polyester fibers as the carpet face yarn. It has been found that in most cases, a 3 to 4 minute heating time is needed to sufficiently volatilize the dye to enable the vacuum action to pull the dye from the transfer sheet to the face fiber yarns of the carpet. It is equally clear that the invention can be carried out with other dyes, and depending upon the volatility rate of these dyes, different heating temperatures and transfer times may be needed. The essence of the invention herein is in the forming of the transfer sheet as part of the finished product and then the using of a vacuum as a means for drawing the volatilized dye from the transfer sheet to the carpet face yarns to appropriately dye the carpet face yarns.
The invention herein may be practiced using the dyes above described mixed together in different proportions or through the use of other dyes, as clearly set forth in Applicant's copending application Ser. No. 612,907. The inks are prepared in the manner set forth in application Ser. No. 612,907. The total disclosure of U.S. Application Ser. No. 612,907 as far as the usability of different dyes, backing materials and face fiber yarns is applicable to the invention herein. The invention herein is a modification of the structure of the aforesaid copending application by the same Applicant. Wherein, in this application, the transfer is carried out through the use of a vacuum means after heat has volatilized the dye, the aforesaid application either uses a positive air flow through the carpet to transfer the dye or simply permits convection of the dye.
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A pattern is placed on a carpet backing by the use of sublimable dyes. Carpet facing is tufted into the backing. Subsequent heating with vacuum action causes the sublimable dye to move from the carpet backing to the face yarn to provide the dyed pattern on the face yarn.
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This application is a continuation of application Ser. No. 08/500,312 filed Jul. 6, 1995, now abandoned, which is a continuation of application Ser. No. 08/264,379 filed Jun. 23, 1994, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method for producing a multi-ply fabric in which a plurality of unit fabrics are placed one upon another.
2. Description of the Prior Art
FIGS. 8 and 9 show a prior art multi-ply fabric. In these figures, the prior art multi-ply fabric 20 is produced by binding together with a binding yarn 23 two unit fabrics 21, 22 which are woven by intertwining warps and wefts alternately, and placing them one upon the other. The binding yarn 23 is a twine in which cotton fibers are twisted like a hand spun yarn. Since this multi-fabric 20 can be easily woven on a loom, it is used as a material for items such as belts, coats, jackets, slacks and bags.
For instance, to produce a belt made of the multi-ply fabric 20, the multi-ply fabric as a source material is first cut into a predetermined shape, as illustrated in FIG. 10. Then the binding yarn 23 around the rim of the cut multi-ply fabric 20 is cut with scissors or a knife, separating the rims of the unit fabrics 21, 22 from each other, as illustrated in FIG. 11. Thereafter, waste yarn generated after cutting, which is a strand that does not blend in with the unit fabrics 21, 22, is removed. As shown in FIG. 12, the rims of the unit fabrics 21, 22 are folded back toward the inside thereof and pressed with an iron to form a selvage 24. This selvage 24 formed by folding back the rims of the unit fabrics 21, 22 is stitched with a sewing thread 25.
However, since the binding yarn 23 of the prior art multi-ply fabric 20 is a twine, it is woven into the unit fabrics 21, 22 by a great tensile force during the weaving process of the multi-ply fabric 20. In the case of producing a clothing or accessory item using the multi-ply fabric 20 as a source material as described in the foregoing, it is necessary to partially separate the unit fabrics 21, 22 from each other. For instance, in the step of forming the selvage 24, the rims of the unit fabrics 21, 22 are pulled towards opposite directions to separate these unit fabrics 21, 22 from each other so that an opening is formed between them. The binding yarn 23 exposed from this opening is cut with scissors or a cutter. For this reason, the twine as the binding yarn 23 pulls each of the unit fabrics 21, 22 partially with this pulling, resulting in an uneven weave in the unit fabrics 21, 22 providing poor appearance and uncomfortable feel. Therefore, the prior art involves the problem that great skill and a lot of time and labor are required to adjust the degree of tension to be applied and the speed of a continuous pulling in cutting operation. When the binding yarn is cut with scissors or a cutter, close attention must be paid not to damage the unit fabrics 21, 22. Furthermore, it is troublesome to remove waste yarn generated after cutting. Moreover, since such removal must be done all around the rim of a product, operation efficiency is extremely low and it is not easy to implement mass-production of the product.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a method for producing a multi-ply fabric comprising fabrics which can be partially separated from each other with ease.
According to a first aspect of the present invention, there is provided a method for producing a multi-ply fabric which comprises the steps of:
binding a plurality of fabrics 1, 2 together with a binding yarn 3 reinforced by intertwining a soluble thread 4 which melts or dissolves in a treatment solution that does not have an adverse effect on the fabrics, around a insoluble thread 5 (5a) which does not melt in the treatment solution and is not spun to form a multi-ply fabric base 6 in which the fabrics are placed one upon the other; and
dipping the multi-ply fabric base into the treatment solution to melt the soluble thread of the binding yarn in the treatment solution and to remove the soluble thread from the external surface of the non-spun insoluble thread.
According to a second aspect of the present invention, there is provided a method for producing a multi-ply fabric which comprises the steps of:
binding fabrics 1, 2 with a binding yarn 3 prepared by coating the external surface of the above-mentioned insoluble thread 5a with a soluble material 4g which melts in a treatment solution which does not have an adverse effect on the fabrics to form the above-mentioned multi-ply fabric base 6, and
melting the soluble material in the treatment solution to remove it from the external surface of the insoluble thread.
In the method for producing a multi-ply fabric according to the present invention, when a plurality of fabrics are bound together with the binding yarn, the binding yarn has the toughness of a twine since the soluble thread of the binding yarn is intertwined around the external surface of the unspun, insoluble thread, or the soluble material is applied to the external surface of the insoluble thread. Therefore, a loom can be used to bind the plurality of fabrics properly.
When the soluble thread is removed by the above-mentioned solution treatment, it is easy to separate the plurality of unit fabrics from each other because the plurality of fabrics are bound together with the unspun, cotton-like insoluble thread only. In addition, the multi-ply fabric retains an air layer between the unit fabrics as the binding force is not so strong, and, accordingly, has superior heat retention.
Moreover, even in the selvage forming step in the production of clothing or accessories made of multi-ply fabrics, he cotton-like insoluble thread can be easily cut with the fingers by separating the rims of the unit fabrics which have been cut into a predetermined shape.
The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken, in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a multi-ply fabric base which is bound with a binding yarn according to an embodiment of the present invention;
FIG. 2 is a perspective view of the insoluble thread which is not twisted;
FIG. 3 is a perspective view of the soluble thread and the twisted insoluble thread;
FIG. 4 is a perspective view of the binding yarn in which the twisted insoluble thread is intertwined with the soluble thread according to an of the present invention;
FIG. 5 is a diagram explaining the production process of the binding yarn according to the present invention;
FIG. 6 is a diagram explaining the production process of the binding yarn according to another embodiment of the present invention;
FIG. 7 is a sectional view of the binding yarn according to the present invention;
FIG. 8 is a perspective view of a prior art multi-ply fabric;
FIG. 9 is a sectional view of the prior art multi-ply fabric of FIG. 8;
FIG. 10 is a perspective view of a clothing item made of the prior art multi-ply fabric;
FIG. 11 is a sectional view of the prior art multi-ply fabric illustrating the selvage forming process; and
FIG. 12 is a sectional view of the prior art multi-ply fabric illustrating the selvage forming process.
DETAILED DESCRIPTION OF THE INVENTION
A method for producing a multi-ply fabric according to the preferred embodiments of the present invention will be described hereinunder with reference to FIGS. 1 to 7.
Embodiment 1
As shown in FIG. 1, two unit fabrics 1, 2 made of woolen fibers or fibers comprising wool and a binding yarn 3 in which a soluble thread 4 is intertwined around the external surface of an unspun insoluble thread 5 as shown in FIG. 4 are used to form a multi-ply fabric base 6 in which the two unit fabrics 1, 2 are bound together with the binding yarn 3 by a sewing machine so that they are placed one upon another.
A description is given of the above-mentioned binding yarn 3 hereinunder. To prepare the binding yarn 3 for binding the unit fabrics 1, 2 together, fifty twists in the right-hand direction per meter, for example, are first given to the insoluble thread 5a made of wool or cotton (cotton-like fibers before spinning) as shown in FIG. 2 and the thus twisted insoluble thread 5a is spun to form a spun thread 5b as shown in FIG. 3. Then the spun soluble thread 4 which can melt in a solution, such as water soluble vinylon, is placed in parallel to this thread 5b, and fifty twists in the left-hand direction are given to both the spun thread 5b and the soluble thread 4. The resulting binding yarn 3 retains strength as a thread as shown in FIG. 4 because the soluble thread 4 is intertwined around the external surface of the insoluble thread 5 which restores the original state of the insoluble thread 5a made of cotton-like fibers when fifty twists in the left-hand direction are given to the spun thread 5b. FIG. 4 illustrates this state.
In other words, in the binding yarn 3, the spun thread 5b is obtained by giving the first twists in the right-hand direction to the insoluble thread 5a and the second opposite-direction (left-hand-direction) twists given to both the spun thread 5b and the soluble thread 4 releases the intertwine of a plurality of fibers constituting the spun thread 5b so that the plurality of fibers are loosened and the spun thread 5b becomes the insoluble thread 5. That is, this insoluble thread 5 restores the original state of the insoluble thread 5a while it is bound with the soluble thread 4. Even if this binding yarn 3 is used to stitch the unit fabrics 1, 2 together, it retains strength as a binding yarn 3, thus making it easy to sew the unit fabrics 1, 2 with the binding yarn 3.
A weft made of the binding yarn 3 with a pitch of several meters is used to stitch together the unit fabrics 1, 2 by a sewing machine in the same manner as shown in FIG. 8, and then the resulting multi-ply fabric base is dipped into a solution to melt the soluble thread 4. The unit fabrics 1, 2 are bound together only with the insoluble thread 5a made up of cotton-like fibers. This insoluble thread 5a is strong enough to bind the unit fabrics 1, 2 together but can be easily cut with the fingers by separating the unit fabrics 1, 2 from each other. Therefore, only a required portion of the unit fabrics can be separated when necessary.
Unlike an ordinary multi-ply fabric in which unit fabrics are stitched together with a spun thread, this multi-ply fabric is such that the unit fabrics 1, 2 are not bound together at a high density and there is an air layer between the unit fabrics 1, 2. Therefore, this multi-ply fabric has excellent heat retention.
Furthermore, a fabric having a lining can be obtained by using a lining fabric on an inner side thereof. In addition, a fabric providing a sense of high quality and excellent in gas permeability, heat retention and anti-humidity property can be obtained by using wool on both sides or one side thereof.
In the above-described Embodiment 1, strength is provided to the binding yarn by intertwining the soluble thread 4 to be melted later, around the external surface of the unspun (not intertwined) cotton-like insoluble thread 5a. In other words, the insoluble thread 5a alone is easily cut when it is processed by a sewing machine, but when it is reinforced by the insoluble thread 4, it can withstand processing by the sewing machine.
In Embodiment 1, twists have been given to the insoluble thread 5a to form the spun thread 5b. Such a twisted spun thread 5b is commercially available. When a commercially available thread is used, the insoluble thread 4 is placed along this thread 5b as shown in FIG. 3, and these threads are twisted in a direction opposite to the twisting direction of the thread 5b. In other words, when the commercially available thread 5b is used, the twisting step of the insoluble thread 5a can be omitted.
Embodiment 2
As for a method for reinforcing the insoluble thread 5a, as shown in FIG. 5, the soluble thread 4 is pulled out from a spindle S2 which is rotated by rotary mechanism together with the insoluble thread 5a which is pulled out from a spindle S1 through a guide G so that the soluble 4 is intertwined around the external surface of the insoluble thread 5a to obtain the reinforced insoluble thread 5a.
Embodiment 3
In FIG. 6, the insoluble thread 5a fed from a spindle S3 is dipped into a solution of a soluble material 4g which is melted and contained in a tank 4A, and taken from the tank to obtain the reinforced binding yarn 3 coated with the soluble material 4g as shown in FIG. 7. The unit fabrics are bound together with the thus obtained binding yarn 3 and then the soluble material 4g is melted away to obtain a multi-ply fabric bound only with the insoluble thread 5a.
As described on the foregoing pages, a method for producing a multi-ply fabric according to the present invention comprises the steps of: binding together a plurality of fabrics with a binding yarn obtained by intertwining the soluble thread around the external surface of the unspun cotton-like insoluble thread or a binding yarn obtained by coating the external surface of the insoluble thread with the soluble material to form a multi-ply fabric base, and dipping the resulting multi-ply fabric base into a treatment solution to melt the soluble thread or the soluble material in the binding yarn so as to remove it from the insoluble thread. Therefore, a proper sewing operation can be performed due to the toughness of the binding yarn. In addition, since the multiple fibers of the cotton-like insoluble thread which binds the multi-ply fabric are loosened and can be cut by pulling and the unit fabrics can be partially separated with ease, operation efficiency is extremely high and mass-production of products can be easily implemented. For instance, even in the selvage forming step of the production of a clothing or accessory item made of this multi-ply fabric, the insoluble thread can be easily cut by separating the rims of the unit fabrics, which have been cut into a predetermined shape, with the fingers and not using scissors or a cutter. In this case, there is no inconvenience that the insoluble thread partially pulls the fibers of the unit fabrics.
Furthermore, according to the present invention, since the cotton-like insoluble thread before spinning binds together a plurality of fabrics flexibly, a proper air-layer can be maintained between the fabrics, thereby making it possible to provide a multi-ply fabric having heat retaining and high-grade properties.
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A process for making a multi-ply fabric, which includes the steps of applying a water soluble material, which has no adverse effect on fabrics, around a water insoluble thread to provide a binding yarn; binding a plurality of unit fabrics one upon another with the binding yarn to provide a multi-ply fabric; putting the multi-ply fabric in water to dissolve the water soluble material thereby providing a multi-ply fabric bound with only the water insoluble thread.
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This application is a continuation, of application Ser. No. 09/123,502, filed Jul. 28, 1998 now U.S. Pat. No. 6,233,053 which claims priority to Provisional Patent Application No. 60/054,063 filed Jul. 29, 1997 which are incorporated herein by reference in their entireties .
BACKGROUND OF THE INVENTION
The present invention relates generally to measurement of sheet surface characteristics, and more particularly to measurement of gloss and high gloss, on paper using a single device.
DESCRIPTION OF THE PRIOR ART
One of the parameters used in determining the quality of a surface is the surface luster or the gloss of the surface. For example, in paper production, various grades of paper having different surface gloss are produced to suit various applications. During paper production, it is desirable to periodically or continuously measure the gloss of the surface of the paper to ensure that the paper surface has the desired gloss.
Typically, the surface gloss of paper is measured using a gloss gauge during the last step of paper production before the finished paper, which is manufactured in a continuous sheet, is packaged in the form of rolls. The rolls of paper are then shipped to paper products manufacturers who process the paper sheet in accordance with the intended use.
Certain devices for determining the gloss of paper surfaces comprise an optical system which measures the intensity of a beam of light reflected from the paper surface. Typically, the gloss of the paper surface is determined by comparing its reflectance to the reflectance of a known gloss standard, such as, for example, a glass tile having a polished surface with a known gloss.
Specifically, in measuring the reflectance of the paper surface, light is projected onto the surface, and a sensor which is responsive to the intensity of light is positioned to measure the intensity of the light reflected from the paper surface. The gloss gauge measures the reflectance of a tile surface in the same manner by substituting the tile surface for the paper surface. The reflectance of the paper surface is referenced to the reflectance of the tile surface, thereby providing a measurement of the gloss of the paper surface. In practice, the reflectance measurement of the tile surface is periodically performed, off-sheet and between scans, as the gloss gauge scans back and forth across the paper surface. The gloss gauge is calibrated during each such measurement with the known reflectance of the tile surface.
Two gloss level measurements have evolved from this basic gloss gauging technique under DIN 54502. For regular gloss measurements, measurements are taken using a 75° angle for the incident light beam from perpendicular to the measured surface, and for high gloss, measurements are taken using a 45° angle for the incident light beam from perpendicular to the measured surface. Thus, if both measurements are desired on the same machine, in the past, two separate DIN standard measuring devices were needed. This double requirement not only causes a slower process, but also involves twice the equipment which must be purchased, maintained, and upgraded, etc. This situation is particularly troublesome considering the only difference between the two standards is the angle of the light beam striking the surface to be measured for gloss.
SUMMARY OF THE INVENTION
The present invention addresses the above issues by providing a single gloss sensor which can perform both the DIN gloss measurement and DIN high gloss measurement using the same hardware, and with minimal delay between the two measurements.
In a first embodyment, the invention functions by providing redirecting mirrors which alter the path of the light source used for the gloss measurements from a position which measures gloss (75°) to a position which measures high gloss (45°).
In a second embodiment, optical fibers direct measurement light beams to the necessary measurement angles.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic diagram of a system incorporating the applicant's invention which is in position to take DIN gloss measurements.
FIG. 2 shows a schematic diagram of a system incorporating the applicant's invention which is in position to take DIN high gloss measurements.
FIG. 3 shows the applicant's system implemented using optical fibers, rather than mirrors.
FIG. 4 shows a more compact system implemented using optical fibers.
FIG. 5 shows a second scheme for first method gloss signal correction.
FIG. 6 shows a system including two step gloss signal correction.
DETAILED DESCRIPTION
A schematic diagram of a system incorporating the applicant's invention and which is in position to take DIN gloss measurements is shown in FIG. 1 .
The disclosed gloss sensor consists of excitation source or lamp 1 , first and second collimators 2 and 3 , respectively, six mirrors 4 - 9 of which 5 and 8 are movable, filter 10 , and detector 11 , as shown in FIG. 1 . Source or lamp 1 is a filament lamp which produces intense CW radiation in visible and IR regions.
To provide DIN gloss (75°) measurements. The radiation produced by source 1 is collimated by the first collimator 2 into a parallel beam, which is reflected by mirror 9 to the paper surface. As is shown in the FIG. 1, mirrors 5 and 8 are positioned out of the path of the beam from the laser source. In this mode, the parallel beams are incident on the paper plane with angle of 75 20 . The light beam reflected from the paper plane are thereafter directed by mirror 4 to second collimator 3 , which condenses radiation on detector 11 after is passes through filter 10 .
In order to provide DIN high gloss 45° measurements, mirrors 5 and 8 are rotated so that they cause the beam of light from light source 1 to reflect off mirrors 7 and 8 before striking the paper plane at an angle of 45°, as shown in FIG. 2 . After specular reflection from the paper plane, the beam from source 1 reflects from mirror 6 to mirror 5 . Finally, the beam reflects from mirror 4 through collimator 3 to detector 11 , after passing through filter 10 .
For both modes of operation, the coefficient of reflection from the paper surface is proportional to paper gloss. From the beam received at detector 11 , the gloss may therefore be calculated.
A second embodiment of the applicant's invention is shown in FIG. 3 . In this system, optical fibers are used as the source of incident light beams. By using multiple optical fibers, measurement of both gloss and high gloss can be performed simultaneously. Like in the first embodiment, condencers and detectors are used on the receiving side of the sensor, to collect gloss signals.
A more detailed description of FIG. 3 is now provided. Source 20 , is a filament lamp which produces intense CW radiation in visible and IR regions. The radiation is modulated by tuning forks 21 and 22 , which for reasons to be described later, resonate at different frequencies. The radiation is focused on optical fibers 23 and 24 , using lenses 25 and 26 , respectively, which deliver radiation to collimators 28 and 27 , respectively. The output tip of the optical fiber is practically an ideal point light source. The optical fibers serve as a diffuser and an optical mode mixer. The fiber tips are positioned at the focal point of the collimator lenses.
To correct for source variations or other system disturbances, further optical fibers 34 and 35 deliver optical radiation to reference detectors 36 and 37 . The beams of radiation used for reference are split off after radiation from source 20 has passed through lenses 25 and 26 , and tuning forks, 21 and 22 are used to modulate the signal. The reference is used to determine gloss by determining the percent of light reflection from the sample (i.e. paper 29 ) relative to the standard. The counts or units of the measurement channel are then divided by the counts on the reference channel to obtain a ratio. Gloss measurement is a slope times this ratio plus an offset.
In order to prevent interference between 45°and 75° channels, modulation of the light radiation is provided with different frequencies using the tuning forks 21 and 22 .
A further modification of the embodiment is possible if conservation of space is a concern. FIG. 4 shows such a system. Collimator 41 and detector 42 for the 45° measurement are brought in closer to the measurement point, by moving 75° collimator 43 and detector 44 closer together, so that their incident and reflected beams are perpendicular to the measured surface. To provide the proper angle on the paper, additional lenses 45 and 46 are positioned to redirect incident and reflected beams to the necessary angles at the paper surface, and to detector 44 , respectively.
Variations on the reference channel are also possible, as outlined in FIGS. 5 and 6, particularly for circumstances wherein the measurement beams must pass through sensor windows (i.e. glass) or some other optical disturbance likely to alter the measurement signal. For simplicity, the high gloss portions of the system have not been labeled in FIG. 5, since they are identical to the gloss components, only at a slightly different locations. In FIG. 5, optical fiber 50 delivers a light beam from source 51 in a similar manner to systems already described. After light from optical fiber 50 passes through collimator 52 the beam must pass through a glass window 53 to reach paper surface 54 to be measured. The reflected light beam must pass through another (or part of the same) glass window 55 before reaching a second collimator 56 and a detector 57 . To compensate for dirt build-up on the glass windows, a reference fiber 58 passes a light beam through a GRIN (gradient index) lens 59 , through the window glass 53 , through second window 55 , to reference beam detector 60 . The reference beam must be modulated at a different frequency than either of the measured signals to prevent interference. Correction of errors caused by the window glass, such as dirt build-up are corrected by combining the measurement signal and the reference signal in a combining device 61 .
As a further embodiment, both corrective signals could be used to improve the measurement accuracy since they each correct for a different error. A system using both reference measurements appears in FIG. 6 . In this figure, the gloss (75°) measurement components have been omitted entirely for clarity. In the figure, an optic fiber 70 passes a measurement light beam to a collimator 71 . The beam exits the collimator, passing through window 72 , and thereafter strikes paper surface 73 . The reflected light beam passes through window 74 , which may or may not be the same glass as window 72 . Collimator 75 receives this light beam and passes it to detector 76 . To provide a first reference signal, a second optical fiber 77 passes a light beam through a GRIN lens 78 , after being modulated to prevent interference with the measurement signal. The light beam, after exiting GRIN lens 78 passes through windows 72 and 74 , striking reference collimator 79 , and finally reference detector 80 . At the same time, another optic fiber 81 passes a light bean to a reference/detector 82 directly. The measurement signal and the signal from reference/detector 82 are combined in a first combining device 83 to produce a first corrected signal. This corrected signal is thereafter combined with the references signal from detector 80 to form a final corrected gloss signal. From a practical standpoint, reference detector 82 corrects for source variations, while the signal from detector 80 corrects for window glass variations, such as paper dust build-up on the window glass.
Machine direction (MD) and cross direction (CD) DIN gloss and high gloss measurements may all be made with the same device by providing another set of sensors perpendicular to the shown set. In order to prevent interference between 45 and 75 degrees and MD and CD channels, modulation of the light radiation must be provided with different frequencies for each beam incident on the paper, for a total of four frequencies.
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. For example, the disclosed sensor can provide also 20, 60, and 85 degrees specular gloss measurements according to ISO 2.813 standards. 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 equivalency of the claims are intended to be embraced therein.
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A single gloss sensor which can perform both DIN gloss measurement and DIN high gloss measurement, using the same hardware, and with minimal delay between the two measurements. The gloss sensor functions by directing light beams from a source to two different positions, either concurrently, or sequentially, between a position which measures gloss (75.degree) and a position which measures high gloss (45.degree). The gloss sensor also provides a reference light beam for correction of errors caused by the window glass, such as by dirt buildup.
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RELATED APPLICATIONS
[0001] This application is a continuation patent application of pending U.S. patent application Ser. No. 11/198,522, filed Aug. 5, 2005, the disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates to a shingle, such as a roofing shingle, and in particular, to a roofing shingle having an improved nail zone.
BACKGROUND OF THE INVENTION
[0003] Asphalt-based roofing materials, such as roofing shingles, roll roofing and commercial roofing, are installed on the roofs of buildings to provide protection from the elements, and to give the roof an aesthetically pleasing look. Typically, the roofing material is constructed of a substrate such as a glass fiber mat or an organic felt, an asphalt coating on the substrate, and a surface layer of granules embedded in the asphalt coating.
[0004] A common method for the manufacture of asphalt shingles is the production of a continuous sheet of asphalt material followed by a shingle cutting operation, which cuts the material into individual shingles. In the production of asphalt sheet material, either a glass fiber mat or an organic felt mat is passed through a coater containing hot liquid asphalt to form a tacky, asphalt coated sheet. Subsequently, the hot asphalt coated sheet is passed beneath one or more granule applicators, which discharge protective and decorative surface granules onto portions of the asphalt sheet material.
[0005] In certain types of shingles, it is especially desired that the shingles define a sufficiently wide area, often known in the industry as the “nail zone,” in order to make installation of roofs using shingles, such as laminated shingles, more efficient and secure. One or more lines or other indicia painted or otherwise marked longitudinally on the surface of the shingle may define such a nail zone. It is especially desired that the shingles define a nail zone that allows the installers to have some latitude in the nail placement.
[0006] Additionally, the leading edge of some shingles may experience lift off in high wind situations. Therefore, there is also a need for shingles where the shingles have a sufficiently high nail pull-through value so that the installed shingles have improved performance in high wind situations.
SUMMARY OF THE INVENTION
[0007] The above objects as well as other objects not specifically enumerated are achieved by a roofing shingle. The roofing shingle includes an overlay sheet including a headlap portion and a tab portion and an underlay sheet secured to the overlay sheet such that a region of the underlay sheet overlaps a region of the headlap portion of the overlay sheet. Said underlay sheet has a substantially uniform thickness. A reinforcement member is secured to the headlap portion. The reinforcement member is formed from a material selected from the group consisting of paper, film, scrim, woven, and non-woven material. The reinforcement member and the portion of the headlap portion to which the reinforcement member is secured to improve nail pull-through. At least some of the reinforcement member does not overlap the overlapping regions of the headlap portion and the underlay sheet. Said reinforcement member provides said overlay sheet with a non-uniform thickness.
[0008] According to this invention there is also provided a roofing shingle. The roofing shingle includes an overlay sheet including a headlap portion and a tab portion. An underlay sheet is secured to the overlay sheet such that a region of the underlay sheet overlaps a region of the headlap portion of the overlay sheet, said underlay sheet having a uniform thickness. A reinforcement member is secured to the headlap portion, the reinforcement member being formed from a woven material. At least some of the reinforcement member does not overlap the overlapping regions of the headlap portion and the underlay sheet. The headlap portion defines a first nail pull-through value. The reinforcement member and the headlap portion define a second nail pull-through value that is at least 13.3 percent greater than the first nail pull-through value. Said reinforcement member provides said overlay sheet with a non-uniform thickness.
[0009] Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the various embodiments, when read in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic elevational view of an apparatus for making shingles according to the invention.
[0011] FIG. 2 is a perspective view of a laminated shingle having a reinforcement member in accordance with this invention.
[0012] FIG. 3 is a schematic sectional view of a pair of laminated roofing shingles of the prior art stacked together, shown in exaggerated thickness to illustrate humping of the stacked shingles.
[0013] FIG. 4 is a schematic sectional view of a pair of laminated roofing shingles according to the invention stacked together, shown in exaggerated thickness to illustrate how the reinforcement members of adjacent shingles cooperate to reduce humping of the stacked shingles.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Referring now to the drawings, there is shown in FIG. 1 an apparatus 10 for manufacturing an asphalt-based roofing material according to the invention. In the illustrated embodiment, the manufacturing process involves passing a continuous sheet 12 in a machine direction (indicated by the arrows) through a series of manufacturing operations. The sheet usually moves at a speed of at least about 200 feet/minute (61 meters/minute), and typically at a speed within the range of between about 450 feet/minute (137 meters/minute) and about 800 feet/minute (244 meters/minute). The sheet, however, may move at any desired speed.
[0015] In a first step of the illustrated manufacturing process, a continuous sheet of substrate or shingle mat 12 is payed out from a roll 14 . The substrate can be any type known for use in reinforcing asphalt-based roofing materials, such as a non-woven web of glass fibers. The shingle mat 12 may be fed through a coater 16 where an asphalt coating is applied to the mat 12 . The asphalt coating can be applied in any suitable manner. In the illustrated embodiment, the mat 12 contacts a roller 17 , that is in contact with a supply of hot, melted asphalt. The roller 17 completely covers the mat 12 with a tacky coating of hot, melted asphalt to define a first asphalt coated sheet 18 . In other embodiments, however, the asphalt coating could be sprayed on, rolled on, or applied to the sheet by other means. Typically, the asphalt material is highly filled with a ground stone filler material, amounting to at least about 60 percent by weight of the asphalt/filler combination.
[0016] A continuous strip of a reinforcement material or tape 19 , as will be described in detail herein, may then be payed out from a roll 20 . The reinforcement tape 19 adheres to the first asphalt coated sheet 18 to define a second asphalt coated sheet 22 . In one embodiment, the reinforcement tape 19 is attached to the sheet 18 by the adhesive mixture of the asphalt in the first asphalt coated sheet 18 . The reinforcement tape 19 , however, may be attached to the sheet 18 by any suitable means, such as other adhesives. In one embodiment, the tape 19 is formed from polyester. In another embodiment, the tape 19 is formed from polyolefin, such as polypropylene or polyethylene. The tape 19 , however, can be formed from any material for reinforcing and strengthening the nail zone of a shingle, such as, for example, paper, film, scrim material, and woven or non-woven glass.
[0017] The resulting second asphalt coated sheet 22 may then be passed beneath a series of granule dispensers 24 for the application of granules to the upper surface of the second asphalt coated sheet 22 . The granule dispensers can be of any type suitable for depositing granules onto the asphalt coated sheet. A granule dispenser that can be used is a granule valve of the type disclosed in U.S. Pat. No. 6,610,147 to Aschenbeck. The initial granule blender 26 may deposit partial blend drops of background granules of a first color blend on the tab portion of the second asphalt coated sheet 22 in a pattern that sets or establishes the trailing edge of subsequent blend drops of a second color blend (of an accent color) and a third color blend (of a different accent color). For purposes of this patent application, the first color blend and the background granules are synonymous. The use of initially applied partial blend drops to define the trailing edge of subsequent blend drops is useful where accurate or sharp leading edges are possible, but accurate trailing edges at high shingle manufacturing speeds are difficult.
[0018] As is well known in the art, blend drops applied to the asphalt coated sheet are often made up of granules of several different colors. For example, one particular blend drop that is supposed to simulate a weathered wood appearance might actually consist of some brown granules, some dark gray granules, and some light gray granules. When these granules are mixed together and applied to the sheet in a generally uniformly mixed manner, the overall appearance of weathered wood is achieved. For this reason, the blend drops are referred to as having a color blend, which gives an overall color appearance. This overall appearance may be different from any of the actual colors of the granules in the color blend. Also, blend drops of darker and lighter shades of the same color, such as, for example, dark gray and light gray, are referred to as different color blends rather than merely different shades of one color.
[0019] As shown in FIG. 1 , the series of dispensers 24 includes four color blend blenders 26 , 28 , 30 , and 32 . Any desired number of blenders, however, can be used. The final blender may be the background blender 34 . Each of the blenders may be supplied with granules from sources of granules, not shown. After the blend drops are deposited on the second asphalt coated sheet 22 , the remaining, uncovered areas are still tacky with warm, uncovered asphalt, and the background granules from the background blender 34 will adhere to the areas that are not already covered with blend drop granules. After all the granules are deposited on the second asphalt coated sheet 22 by the series of dispensers 24 , the sheet 22 becomes a granule covered sheet 40 .
[0020] In one embodiment, the reinforcement tape 19 includes an upper surface to which granules substantially will not adhere. The reinforcement tape 19 , however, may include an upper surface to which granules will adhere. For example, the apparatus 10 may include any desired means for depositing granules onto substantially the entire second asphalt coated sheet 22 , except for the portion of the second asphalt coated sheet 22 covered by the tape 19 , as best shown in FIG. 2 . Alternately, granules may be deposited onto substantially the entire second asphalt coated sheet 22 , including the tape 19 , but wherein the reinforcement tape 19 includes an upper surface to which granules substantially will not adhere.
[0021] The granule covered sheet 40 may then be turned around a slate drum 44 to press the granules into the asphalt coating and to temporarily invert the sheet so that the excess granules will fall off and will be recovered and reused. Typically, the granules applied by the background blender 34 are made up by collecting the backfall granules falling from the slate drum 44 .
[0022] The granule covered sheet 40 may subsequently be fed through a rotary pattern cutter 52 , which includes a bladed cutting cylinder 54 and a backup roll 56 , as shown in FIG. 1 . If desired, the pattern cutter 52 can cut a series of cutouts in the tab portion of the granule covered sheet 40 , and cut a series of notches in the underlay portion of the granule covered sheet 40 .
[0023] The pattern cutter 52 may also cut the granule covered sheet 40 into a continuous underlay sheet 66 and a continuous overlay sheet 68 . The underlay sheet 66 may be directed to be aligned beneath the overlay sheet 68 , and the two sheets may be laminated together to form a continuous laminated sheet 70 . As shown in FIG. 1 , the continuous underlay sheet 66 may be routed on a longer path than the path of the continuous overlay sheet 68 . Further downstream, the continuous laminated sheet 70 may be passed into contact with a rotary length cutter 72 that cuts the laminated sheet into individual laminated shingles 74 .
[0024] In order to facilitate synchronization of the cutting and laminating steps, various sensors and controls may be employed. For example, sensors, such as photo eyes 86 and 88 can be used to synchronize the continuous underlay sheet 66 with the continuous overlay sheet 68 . Sensors 90 can also be used to synchronize the notches and cutouts of the continuous laminated sheet with the end cutter or length cutter 72 .
[0025] In one embodiment, the reinforcement tape may be attached to the shingle mat 12 prior to the application of the asphalt coating, as shown at 19 A in FIG. 1 . The tape 19 A may be attached to the shingle mat 12 by any suitable means, such as hot, melted asphalt, or other adhesives.
[0026] In another embodiment, the reinforcement tape may be attached to the granule covered sheet 40 , as shown at 19 B in FIG. 1 . The tape 19 B may be attached to the granule covered sheet 40 by any suitable means, such as hot, melted asphalt, or other adhesives.
[0027] In another embodiment, the reinforcement tape may be attached to a lower surface (downwardly facing as viewed in FIG. 1 ) of the mat 12 , the first asphalt coated sheet 18 , the second asphalt coated sheet 22 , or the granule covered sheet 40 , as shown at 19 C and 19 D in FIG. 1 . The tape 19 C may be attached to the mat 12 , the first asphalt coated sheet 18 , the second asphalt coated sheet 22 , or the granule covered sheet 40 by any suitable means, such as hot, melted asphalt, other adhesives, or suitable fasteners. In such an embodiment, the reinforcement tape 19 C and 19 D may be attached to the lower surface of the nail zone of either of the overlay sheet 68 or the underlay sheet 66 , thereby reinforcing and strengthening the nail zone as described herein.
[0028] It will be understood, however, that in any of the embodiments described herein, reinforcement material may be applied as an extruded or liquid material, such as a polymer, that will adhere to the mat 12 , the first sheet 18 , the second sheet 22 , the granule covered sheet 40 , or the lower surface of the underlay sheet 66 or the overlay sheet 68 . Additionally, the reinforcement material may be applied to the laminated roofing shingle 74 , as described below.
[0029] Referring now to FIG. 2 , a laminated roofing shingle is shown generally at 74 . In the illustrated embodiment, the shingle 74 includes the overlay sheet 68 attached to the underlay sheet 66 and has a first end 74 A and a second end 74 B. The shingle 74 also includes a longitudinal axis A. The overlay sheet 68 may include a headlap portion 76 and a tab portion 78 . The headlap portion 76 may include a lower zone 76 A and an upper zone 76 B. The tab portion 78 defines a plurality of tabs 80 and cutouts 82 between adjacent tabs 80 . In the illustrated embodiment, the tab portion 78 includes four tabs 80 , although any suitable number of tabs 80 may be provided. The headlap portion 76 and the tabs 80 may include one or more granule patterns thereon. Each cutout 82 has a first height H 1 . In the illustrated embodiment, the cutouts 82 are shown as having the same height H 1 . It will be understood however, that each cutout 82 may be of different heights. A line B is collinear with an upper edge 82 A of the cutouts 82 and defines an upper limit of an exposed region 84 of the underlay sheet 66 . In the illustrated embodiment, the height of the exposed region 84 is equal to the first height H 1 , although the height of the exposed region 84 may be any desired height. In a shingle wherein the cutouts 82 have different heights, the line B may be collinear with an upper edge 82 A of the cutout 82 having the largest height. In the illustrated embodiment, the overlay sheet 68 has a second height H 2 .
[0030] The reinforcement tape 19 may be disposed longitudinally on the headlap portion 76 . In the illustrated embodiment, the tape 19 extends longitudinally from the first end 74 A to the second end 74 B of the shingle 74 within the lower zone 76 A of the headlap portion 76 . A lower edge 19 A of the tape 19 may be spaced apart from the line B by a distance D 1 , and an upper edge 19 B of the tape 19 may be spaced apart from the line B by a distance D 2 . In one embodiment, the distance D 1 is within the range of from about ¼ inch to about ¾ inch. In another embodiment, the distance D 1 is about ½ inch. In one embodiment, the distance D 2 is within the range of from about 1¾ inches to about 2¼ inches. In another embodiment, the distance D 2 is about 2 inches. The distances D 1 and D 2 may, however, be of any other desired length. For example, if desired, the tape 19 may substantially cover the entire headlap portion 76 of the overlay sheet 68 . It will be further understood, however, that one or more additional lengths of tape may be disposed longitudinally on the headlap portion 76 , such as shown by the phantom line 19 ′ in FIG. 2 . It will be understood that the reinforcement material need not extend from the first end 74 A to the second end 74 B of the shingle 74 , and may be disposed in one or more sections or portions on the shingle 74 .
[0031] The tape 19 defines a nail zone 98 and may include text such as “nail here •”, as shown in FIG. 2 . It will be understood, however, that any other text or other indicia may be included on the tape 19 . It will also be understood that the tape 19 can be provided without such text or indicia. Such indicia on the tape 19 ensure that the nail zone 98 may be easily and quickly identified by the shingle installer.
[0032] In the embodiment illustrated in FIG. 2 , the underlay sheet 66 includes a leading edge 66 A and a trailing edge 66 B and has a third height H 3 . In the illustrated embodiment, the trailing edge 66 B of the underlay sheet 66 is spaced apart from the line B by a distance D 3 . As shown, the distance D 3 is about ⅜ inch, however, the distance D 3 may be any desired distance.
[0033] In the illustrated embodiment, the third height H 3 of the underlay sheet 66 is less than one-half the second height H 2 of the overlay sheet 68 . The overlay sheet 68 and the underlay sheet 66 thereby define a two-layer portion of the laminated shingle 74 and a single-layer portion of the laminated shingle 74 , wherein at least a portion of the tape 19 is adhered to the single-layer portion of the laminated shingle 74 . Alternately, the third height H 3 of the underlay sheet 66 may be equal to one-half the second height H 2 of the overlay sheet 68 , or greater than one-half of the second height H 2 of the overlay sheet 68 . Such a relationship between the underlay sheet 66 and the overlay sheet 68 allows the tape 19 to be positioned such that a reinforced nail zone is provided at a substantially single-layer portion of the shingle 74 .
[0034] In another embodiment of the invention, a layer of material, such as talc or sand, may be applied to the first asphalt coated sheet 18 shown in FIG. 1 . The material may be applied by any desired means to an upper surface of the first asphalt coated sheet 18 . In one embodiment, the material may be applied to the portion of the first asphalt coated sheet 18 that will become the portion of the overlay sheet 66 shown covered by the tape 19 in FIG. 2 . Such a material may reduce tackiness of the portions of the second asphalt coated sheet 22 to which the material has been applied, and thereby provide a surface to which granules substantially will not adhere.
[0035] In the exemplary shingle 74 illustrated in FIG. 2 , the shingle 74 may have a nail pull-through value, measured in accordance with a desired standard, such as prescribed by ASTM test standard D3462. For example, the shingle 74 may have a nail pull-through value that is greater than in an otherwise identical shingle having no such tape 19 . In one embodiment, the shingle 74 may have a nail pull-through value within the range of from about ten percent to about 100 percent greater than in an otherwise identical shingle having no such tape 19 . In another embodiment, the shingle 74 may have a nail pull-through value about 50 percent greater than in an otherwise identical shingle having no such tape 19 .
[0036] In another embodiment, a shingle having a reinforcement tape 19 formed from polyester film having a thickness of about 0.5 mils, may have a nail pull-through value about 13.3 percent greater than in an otherwise identical shingle having no such tape 19 .
[0037] In another embodiment, a shingle having a reinforcement tape 19 formed from polyester film having a thickness of about 3.0 mils, may have a nail pull-through value about 62.3 percent greater than in an otherwise identical shingle having no such tape 19 .
[0038] In another embodiment, a shingle having a reinforcement tape 19 formed from polyester film having a thickness of about 4.0 mils, may have a nail pull-through value about 86.0 percent greater than in an otherwise identical shingle having no such tape 19 .
[0039] In another embodiment, a shingle having a reinforcement tape 19 formed from polyester film having a thickness of about 5.0 mils, may have a nail pull-through value about 112.7 percent greater than in an otherwise identical shingle having no such tape 19 .
[0040] Because there may be substantially no granules in the portion of the overlay sheet 68 covered by the tape 19 , the weight of the shingle 74 may be reduced relative to an otherwise identical shingle having no such tape 19 . For example, the weight of the exemplary shingle 74 illustrated in FIG. 2 , may be reduced within the range of from about four percent to about six percent relative to the weight of an otherwise identical shingle having no such tape 19 . The material and transportation cost may also be reduced.
[0041] Although the invention has been disclosed in the context of a laminated shingle 74 , it will be understood that the reinforcement tape 19 may be attached to any other type of shingle, such as a single layer shingle.
[0042] As shown in FIG. 3 , laminated roofing shingles 100 of the prior art are stacked in a bundle 102 . Only a pair of such shingles 100 are illustrated in FIG. 3 , with every other shingle 100 inverted and turned 180 degrees. It will be understood, however, that the shingles 100 may be stacked such that every other of such shingles 100 are either inverted or turned 180 degrees, or both. This stacking method minimizes uneven build in the bundle 102 caused by the difference in thickness between the area of the shingle 100 that includes the underlay sheet 106 and the area that does not include the underlay sheet 106 . A problem may occur, however, along a central area 108 of the bundle 102 because central areas 110 of the shingles 100 are double-layered, whereas the cutout portions 112 of the shingles 100 adjacent the central areas 110 are single-layered. The difference in thickness causes a ridge or hump 114 along the central area 108 of the bundle 102 that becomes progressively higher as the number of shingles 100 in the bundle 102 increases.
[0043] FIG. 4 is a schematic sectional view of a representative pair of stacked shingles 74 manufactured according to the present invention. As shown in FIG. 4 , the laminated roofing shingles 74 are stacked such that every other of the shingles 74 is inverted and turned 180 degrees relative to an adjacent one of the shingles 74 to define a bundle 99 . It will be understood, however, that the shingles 74 may be stacked such that every other of such shingles 74 are either inverted or turned 180 degrees, or both. The bundle 99 includes a central area 92 . In the illustrated embodiment, the central area 92 includes the lower zones 76 A and reinforcement tape 19 of each shingle 74 , and includes the portion of each laminated roofing shingle 74 wherein the shingle 74 is double-layered. In contrast to the prior art shingles 100 , when the laminated shingles 74 of the invention are stacked, the areas of the adjacent shingles 74 having no granules, such as the areas covered by the reinforcement tapes 19 , cooperate to advantageously reduce humping in the central area 92 of the bundle of stacked shingles 74 . As best shown in FIG. 4 , the central area 92 of the bundle, as represented by the pair of shingles 74 illustrated, has a fourth height H 4 substantially identical to a fifth height H 5 of a remainder of the bundle outside of the central area 92 .
[0044] The principle and mode of operation of this invention have been described in its various embodiments. However, it should be noted that this invention may be practiced otherwise than as specifically illustrated and described without departing from its scope.
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A roofing shingle is provided. The roofing shingle includes an overlay sheet including a headlap portion and a tab portion and an underlay sheet secured to the overlay sheet such that a region of the underlay sheet overlaps a region of the headlap portion of the overlay sheet. Said underlay sheet has a substantially uniform thickness. A reinforcement member is secured to the headlap portion. The reinforcement member is formed from a material selected from the group consisting of paper, film, scrim, woven, and non-woven material. The reinforcement member and the portion of the headlap portion to which the reinforcement member is secured to improve nail pull-through. At least some of the reinforcement member does not overlap the overlapping regions of the headlap portion and the underlay sheet. Said reinforcement member provides said overlay sheet with a non-uniform thickness.
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CROSS REFERENCE TO RELATED CASE
This application is a continuation-in-part application of U.S. Pat. application Ser. No. 431,137, filed Jan. 7, 1974 and now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to fire detectors of the ionization type that employ an ionization chamber for detecting products of combustion, and more particularly to supervisory circuits for such detectors which assure that the detectors are operating properly.
2. Prior Art
In order to provide maximum fire protection, it is desirable to monitor the operation of the fire protection device to assure that the device is receiving power and that the unit is otherwise operating properly.
Several systems for monitoring the power supplied to a fire protection device are known. These systems generally monitor the voltage of the power supply of the unit and compare the voltage thereof with a reference voltage obtained from, for example, a separate reference battery or reference voltage source, such as a zener diode.
Whereas these techniques provide a way to monitor the power supplied to a fire protection unit, in systems using a reference battery, such as described in U.S. Pat. No. 3,594,751, failure of the reference battery would render the monitoring circuit inoperative. In systems using a zener diode reference, a complete sudden failure of the main power supply would not be detected. Furthermore, the prior art circuits only detect malfunctions in the power supply, not in the detector circuitry itself.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved monitoring system for a fire detection device.
It is a further object of this invention to provide a monitoring circuit for a fire detecting device that assures that power is applied to the unit and that the unit is otherwise operating properly.
It is another object of the invention to provide a variable sensitivity fire detection device of the ionization type that includes a monitoring system that assures that the detecting device is operative at the proper sensitivity.
In accordance with a preferred embodiment of the invention, a MOS-FET transistor amplifier is employed to sense the impedance variations of the ionization chamber which occur in the presence of products of combustion and to provide a voltage representative of the impedance of the chamber. A differential amplifier having a variable reference voltage applied to one input thereof is connected to the MOS-FET transistor amplifier and triggers an audible alarm when the output voltage from the MOS-FET amplifier drops below the reference voltage applied to the differential amplifier.
A transistorized monitoring circuit is connected to the MOS-FET transistor and to the emitter impedance of the differential amplifier and energizes an indicator light when the bias on the differential amplifier is proper. If the bias is incorrect, indicative of a malfunction in the power supply, detector circuit or an incorrect sensitivity setting, the indicator light is extinquished.
DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a detailed schematic diagram of one embodiment of fire detector of the ionization type employing variable sensitivity and monitoring circuitry according to the invention; and
FIG. 2 is a detailed schematic diagram of a second embodiment of fire detector of the ionization type employing variable sensitivity and monitoring circuitry according to the invention.
DETAILED DESCRIPTION
Referring to FIG. 1, a transformer 10 is connected to a 120 volt power line source and to four rectifier diodes 12, 14, 16 and 18 to provide a nominal 12 volts DC to operate the fire detector circuitry. In an alternate embodiment, a battery may be used in place of the transformer 10 and the four diodes to provide a self-contained battery operated unit. Four capacitors 20, 22, 24 and 26 are used to filter the rectifier output voltage from the diodes 12, 14, 16 and 18 and to remove voltage transients resulting from transients on the power line. The voltage applied to the sensing circuitry is regulated to a predetermined fixed voltage, such as, for example, 8.2 volts in this embodiment, by the zener diode 28, which is connected to the rectifier diodes through a resistor 30 and a diode 32.
The fire detection circuitry comprises an ionization chamber 34 having a cup-shaped member 36, a target 38 and a radioactive source of ions 40. The source 40 emits alpha particles which ionize the ambient air passing between the cup-shaped member 36 and the target 38 to provide current flow between the cup-shaped member 36 and the target 38. Products of combustion in the ambient air being of greater mass than ambient air molecules, cause a reduction (pursuant to the formula force equals mass times acceleration) in the amount of ion current flowing between the cup member 36 and the target 38. Consequently, the impedance of the ionization chamber is increased upon the presence in the air of products of combustion. A more detailed explanation of the operation of the ion chamber is given in U.S. Pat. No. 3,594,751 and our co-pending application Ser. No. 425,307, filed Dec. 17, 1973, assigned to the same assignee.
The target 38 of the ionization chamber 34 is connected to the positive 8.2 volt bus line 42, and the cup-shaped member 36 is connected to ground or common potential through a resistor 44. The junction of the resistor 44 and cup-shaped member 36 is connected to the gate of a MOS-FET transistor 46 to form the sensing means of the detector. The drain of the transistor 46 is connected to ground potential through a resistor 48, and the source thereof is connected to the 8.2 volt bus line 42 through resistors 50 and 52. The junction of the resistors 50 and 52 is connected to the base of a transistor 54, the transistor 54 together with transistor 56 and associated components forming a differential amplifier or first comparison means for comparing signal voltages. The emitters of the transistors 54 and 56 are connected together and coupled to the line 42 through a resistor 58 and a diode 59, the function of which will be explained in a subsequent portion of the specification. The base of the transistor 56 is connected to adjustable reference means or the resistive divider network comprising resistors 60 and 62, and potentiometer 64. The collector of the transistor 54 is connected to the base of a transistor 66, which, in this embodiment, is a Darlington connected transistor pair. The emitter of the transistor 66 is connected to ground, and the collector thereof is connected to a first transducer or alarm means, such as a horn 68, through a resistor 70, to comprise a switch for the horn.
A transistor 72, which comprises the monitoring circuit and second comparison means for comparing signal voltages, has an emitter connected to the junction of the resistor 58 and voltage signal offsettig means or diode 59, and a base connected to the junction of resistors 52 and 50 through a resistor 74. The collector of the transistor 72 is connected through a resistor 76 to the base of a transistor 78, which is also a Darlington connected pair. The emitter of the transistor 78 is connected to ground potential, and the collector thereof is connected to a second transducer or indicator means, such as a light emitting diode 80, through a current limiting resistor 82, to serve as a switch for the light.
In operation, when no products of combustion are present in the ambient air, the potentiometer 64 is adjusted such that the transistor 56 is rendered conductive. The adjustment is made such that the voltage at the base of the transistor 56 is approximately 0.3 volts lower than the voltage at the base of the transistor 54. When transistor 56 is rendered conductive, the transistor 54 is rendered nonconductive, thereby rendering transistor 66 nonconductive to open the circuit to the horn 68.
In the event of a fire, the products of combustion passing between the target 38 and the cup-shaped member 36 will increase the impedance of the ionization chamber 34, thereby lowering the voltage applied to the gate of the transistor 46. The aforementioned drop in voltage causes the conductivity of the transistor 46 to increase, thereby lowering the voltage at the junction of the resistors 50 and 52. When the voltage at the junction of the resistors 50 and 52, which is applied to the base of the transistor 54, drops below the reference voltage present at the base of the transistor 56, the transistor 56 will be rendered nonconductive and the transistor 54 will be rendered conductive. Rendering transistor 54 conductive causes the base to emitter junction of the transistor 66 to be forward biased, thereby saturating the transistor 66 and completing the circuit to energize the first transduced or horn 68. The unit may be readily made more or less sensitive to changes in the impedance of the ionization chamber 34 by adjusting the potentiometer 64 to provide an offset other than 0.3 volts between the bases of the transistors 54 and 56, a smaller offset rendering the unit more sensitive.
When forward potentiometer 64 is correctly set, the voltage across the base to emitter junction of the transistor 54 is approximately 0.3 volts which is insufficient to foward bias the base to emitter junction and to render the transistor conductive. The current flowing through the diode 59 as a result of the conductivity of the transistor 56 causes approximately 0.6 volts to be present across the diode 59. The 0.6 volts present across the diode 59 plus the 0.3 volts across the base to emitter junction of transistor 54 results in a total of 0.9 volts between the anode of the diode 59 and the base of the transistor 54, which is sufficient to turn on the transistor 72. The diode 59 is necessary to provide the additional voltage to turn on the transistor 72, the 0.3 volts across the base to emitter junction of the transistor 54 being insufficient to accomplish this. The aforementioned offset voltages provide satisfactory operation for the circuit shown when silicon transistors are used. However, it should be appreciated that an appropriate change in the offset voltage would be made by one skilled in the art if different transistor types or different circuit configuration were employed.
When the transistor 72 is rendered conductive, current is supplied thereby to the base of the transistor 78 to turn on the second transducer or light source 80 to indicate that the circuit is operating properly.
Should the voltage at the line 42 fail for any reason, the transistor 72 would be rendered nonconductive, thereby rendering transistor 78 nonconductive and extinquishing the light source 80. In similar fashion, should the transistor 46 fail, the most common mode of failure being an open circuit, the voltage at the junction of resistors 50 and 52 would increase, thereby rendering transistor 72 nonconductive and extinquishing the light source 80.
Should the potentiometer 64 be improperly adjusted to provide too high a voltage to the base of the transistor 56, the transistor 56 would be rendered nonconductive and the transistor 54 would be rendered conductive to sound the horn 68. If the potentiometer 64 is improperly adjusted with the voltage at the base of the transistor 56 being too low, the horn would not sound, but the voltage between the anode of the diode 59 and the base of the transistor 54 would be less than 0.9 volts, and the transistor 72 would be rendered nonconductive, thereby extinquishing the light source 80 to indicate improper setting of the potentiometer 64. Hence, the monitoring circuit according to the invention provides the added feature of preventing incorrect setting of the sensitivity adjustment of the unit which could otherwise result in degraded sensitivity of the unit.
Referring to the embodiment of FIG. 2, lead lines 101 and 102 are adapted to be connected to an AC power source, for example 120 volts, with the line 101 being connected to the hot side. The full wave AC of the source is rectified into half wave by the diode 112 having its anode connected to the line 101 which is used to power the alarm and indicating portions of the detector. The half wave 120 volt power is reduced in voltage, for example to 8.2 volts, for use in the sensing and monitoring portions of the detector by a zener diode 128 which is connected through a resistor 130 and diode 131 to the cathode of the diode 112. The anode of the zener diode 128 is connected to the common ground line 102. As an alternative a battery may be used to provide a self contained battery operated detector.
Two capacitors 124 and 126 are connected across the positive low voltage bus line 142 and the common ground 102 for filtering the rectified voltage from diode 131 and to remove voltage transients caused by transients in the source providing essentially DC current between the lines 102 and 142.
The fire detection circuitry of FIG. 2 is similar to that of FIG. 1 and comprises an ionization chamber 134 having a cup-shaped member 136, a target 138 and a radioactive source of ions 140. The target 138 of the ionization chamber 134 is connected through a resistor 139 in series with a thermostat 141 to the positive 8.2 volt bus line 142. The resistor 139 is provided to prevent electric shocks should the lines 101 and 102 be reserved by the installer. The thermostat 141 opens up at approximately 135° F to alarm the detector on heat alone. The cup-shaped member 136 is connected to the gate of a MOS-FET transistor 146. The drain of the transistor 146 is connected to ground potential through a resistor 148, and the source thereof is connected to the 8.2 volt bus 142 through resistors 150 and 152. The junction of the resistors 150 and 152 is connected to the base of the transistor 154, the transistor 154 together with transistor 156 and associated components forming a differential amplifier. The emitters of the transistors 154 and 156 are connected together and coupled to the bus line 142 through a resistor 158 and a diode 159. Alternatively, to suppress line transients the base of the transistor 154 may be capacitively coupled to the bus line 142 by capacitor 155 or, as shown in dashed lines, to its collector by capacitor 155'. The base of the transistor 156 is connected to the resistive divider network comprising resistors 160 and 162, and potentiometer 164. The collector of the transistor 154 is connected to the gate of a switch 166, such as a 200 volt rated SCR. The cathode of the SCR 166 is connected to the ground; the gate thereof is connected to ground by a resistor 165 and a capacitor 167 which prevents self triggering. The anode of SCR 166 is connected to a first transducer or alarm means, such as a 120 volt rated horn 168. The other terminal of the horn 168 is connected to the cathode of diode 112.
A transistor 172, which comprises the monitoring circuit, has an emitter connected to the junction of the resistor 158 and diode 159, and a base connected to the junction of resistors 152 and 150 through a resistor 174. The collector of the transistor 172 is connected through a resistor 176 to the gate of a second switch 178, which is also 200 volt rated SCR. The cathode of the SCR 178 is connected to ground potential; the gate thereof is connected to ground by a resistor 175 and a capacitor 177 which prevents self triggering. The anode of the SCR 178 is connected to a second transducer or indicator means, such as a light emitting diode 180, through a current limiting resistor 182. A resistor 179 is provided in parallel with the SCR 178 as protection for the SCR, the current normally flowing through this resistor with the SCR not triggered being insufficient to light the lamp 180.
Further, electric shielding is provided around the chamber 134 by conductors which are connected to the detector circuit for establishing certain potentials, for example: the lower left quadrant of the chamber 134 is shielded by a conductor S1 connected to the junction of potentiometer 164 and resistor 162; the lower right quadrant of the chamber is shielded by a conductor S2 connected to the junction of the source of the MOS-FET 146 and resistor 150; and the lower center of the chamber is shielded by a conductor S3 connected to the line 102.
In addition for ease of testing and servicing, metering points are provided in the circuit. The metering points terminate at one end in a seven pin base type connector which is adapted to receive a test instrument, and at the other end are connected as follows: M1--base of transistor 156, M2--low voltage bus line 142, M3--not used (not shown), M4--base of transistor 154, M5--not used (not shown), M6--ground line 102, M7--junction of switch 166 and alarm 168. Further, since the point M7 is at 120 volts, a resistor 181 is provided in the metering connection thereof to reduce the possibility of shock. A similar resistor 183 is provided for M4.
Operation of the embodiment of FIG. 2 is similar to that of FIG. 1 and will only be briefly described. When no products of combustion are present in the ambient air, the potentiometer 164 is adjusted to render transistor 156 conductive with the transistor 154 nonconductive. In the event of a fire, the products of combustion increase the impedance of the ionization chamber 134, lower the voltage applied to the gate of the transistor 146 and cause the conductivity of the transistor 146 to increase, lowering the voltage at the junction of the resistors 150 and 152. When the voltage at junction of the resistors 150 and 152 and the base of the transistor 154 drops below the reference voltage present at the base of the transistor 156, the transistor 156 is rendered nonconductive and the tansistor 154 is rendered conductive. Rendering transistor 154 conductive causes the SCR 166 to become conductive so as to energize the horn 168. The sensitivity of the detector to changes in the impedance of the ionization chamber 134 may be altered by adjusting the potentiometer 164.
With the potentiometer 164 correctly set, the voltage across the base to emitter junction of the transistor 154 alone is insufficient to forward bias a base to emitter junction and to render a transistor conductive. The current flowing through the diode 159 as a result of the conductivity of the transistor 156 causes approximately 0.6 volts to be present across the diode 159. The 0.6 volts present across the diode 159 plus the 0.3 volts across the base to emitter junction of transistor 154 results in a total of 0.9 volts between the anode of the diode 159 and the base of the transistor 154, which is sufficient to turn on the transistor 172. When the transistor 172 is rendered conductive, current is supplied thereby to the gate of the second switch 178 to turn on the second transducer or light source 180 to indicate that the circuit is operating properly.
Should the voltage at the line 142 fail for any reason, the transistor 172 would be rendered nonconductive, thereby rendering switch 178 nonconductive and extinguishing the light source 180. In similar fashion, should the transistor 146 fail in its most common mode -- open circuit -- the voltage at the junction of resistors 150 and 152 would increase, thereby rendering transistor 172 nonconductive and extinquishing the light source 180.
Should the potentiometer 164 be improperly adjusted to provide too high a voltage to the base of the transistor 156, the transistor 156 would be rendered nonconductive and the transistor 154 would be rendered conductive to sound the horn 168. If the potentiometer 164 is improperly adjusted with the voltage at the base of the transistor 156 being too low, the horn would not sound, but the voltage between the anode of the diode 159 and the base of the transistor 154 would be less than 0.9 volts, and the transistor 172 would be rendered nonconductive, thereby extinguishing the light source 180 to indicate improper setting of the potentiometer 164. Hence, like the monitoring circuit of FIG. 1, the monitoring circuit of FIG. 2 provides the added feature of preventing incorrect setting of the sensitivity adjustment of the unit which could otherwise result in degraded sensitivity of the unit.
It should be understood that the resistor shown between the collector of transistor 156 and the line 102 could be removed and replaced by a length of conductor, likewise the resistors 150 and 148 could be similarly replaced.
It should be further understood that the fire detector of the present invention can be simplified by omitting the supervision portion. For example, in the embodiment of FIG. 1, the diode 59, resistor 58, transistor 72, resistors 74 and 76, transistor 78 and its bias resistor (not numbered) may be omitted, and the resistor 82 can be connected to ground. Similarly for the embodiment of FIG. 2, the diode 159, resistor 158, transistor 172, resistors 174, 175, 176 and 179, capacitor 177 and SCR 178 may be omitted, and the resistor 182 may be connected to ground.
Having thus described what is regarded to be the preferred forms of the invention, it should be appreciated that various changes, rearrangements and modifications may be made therein without departing from the scope and spirit of the invention, as defined by the appended claims.
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An improved early warning fire detector of the ionization type is provided wherein detection circuitry having adjustable sensitivity is connected to an ionization chamber responsive to products of combustion. A supervisory circuit monitors the unit to assure that power is applied to the unit, that the detecting circuitry is operative and that the unit is operating at the proper sensitivity.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to fungal compositions and methods of using them for control of subterranean termites.
[0003] 2. Description of the Prior Art
[0004] Subterranean termites are particularly destructive pests in tropical and temperate regions throughout the world. In the United States alone, subterranean termites are estimated to cause $1 billion in damage annually including prevention and repair costs. They are known to infest cellulose-based materials including living trees, wooden structures, plant roots and books. One predominant species, the Formosan subterranean termite (FST), Coptotermes formosanus (Shiraki), has become an economically significant pest in the United States in the past 50 years. Reasons for this include their massive colonies which can contain tens of millions of individuals, their ability to attack several species of living trees, and their high level of reproduction. The Formosan subterranean termite is thought to have been transported to the US mainland at the end of World War II when military equipment was shipped back in wooden crates. The infestations have since radiated from the port cities of New Orleans and Lake Charles, La., Houston, Tex. and Charleston, S.C. The cryptic nature of the insects allowed them to establish colonies without being detected and made it difficult to determine the most effective treatment location. The extent of FST infestations has become apparent in dense swarms of flying termites and significant damage to buildings and trees.
[0005] Organochlorine compounds were previously used to control FST, but their sale was banned in 1988. Replacement chemicals are not as persistent [Su et al., Pest Managem. Rev. (1998) 3: 1-13]. In addition, by disturbing soil around a structure when landscaping or compensating for soil subsidence the chemical barriers can be compromised and allow FST access to the structure [Su et al., (1990) Sociobiology 17: 77-94]. Su et al. (1998, supra) review some alternative control methods including non-repellant termiticides and bait technology. In order for these techniques to work they must not repel termites, must be easily transferrable in or on termite bodies and have delayed toxicity which allows transfer from foraging workers to members of the termite colony that do not forage [ Sociobiology (1996) 27: 253-275 and 1998, supra].
[0006] One alternative to chemical control entails use of biological control agents [Culliney et al., Bulletin of Entomological Research (2000) 90: 9-21]. Bacteria, viruses, protozoa and fungi have potential as pathogenic agents. Fungi exhibit qualities which can make them ideal for this application, including a slow-acting nature similar to that of successful chemicals, the ability to self-replicate and the ability of fungal spores to be spread by termite social behavior [Grace et al. (1992) Sociobiology 20: 23-28]. Milner et al. [ Biocontrol Science and Technology (1966) 6: 3-9] review a wide variety of fungal pathogens that have been reported as potential pathogens to termites. Pathogenicity of strains of both Metarhizium anisopliae (Metschnikoff) Sorokin and Beauveria bassiana (Balsamo) Vuillemin have been demonstrated in laboratory colonies of C. formosanus [Delate et al. (1995) J. Appl. Entomol. 119:, 429-433; Wells et al. (1995) J. Entomol. Sci. 30: 208-215]. Jones et al. [Environ. Entomol. (1996) 25:, 481-487] discovered that small numbers of B. bassiana and M. anisopliae spores can be spread throughout a C. formosanus colony without being detected by the termites. Conditions in a termite nest, moderate temperature and high humidity, are conducive to the growth of fungal species and are important factors in fungal survivability and propagation [Kramm et al. (1982) J Invertebr Pathol 39: 1-5.; Ignoffo (1992) Florida Entomol. 75: 516-525]. Stimac et al. (U.S. Pat. No. 6,280,723) teach a novel B. bassiana strain (AATCC 20872) useful in controlling termites of the genera Cryptotermes, Coptotermes, Incistermes, and Reticulitermes. Grooming and other social activity between termites facilitate the spread of fungal infection throughout a colony, which may result in elimination of a colony or a drastic reduction in its numbers and potential to cause economic damage. However, defensive actions such as avoidance of fungi, the removal and burial of fungus-killed termite cadavers and various immune responses can limit the spread of infection in the colony.
[0007] Baits containing effective entomopathogenic agents may allow the “horizontal transmission” of a fungal pathogen from termite to termite and eventual spread to the entire colony. They would provide long-term control or suppression of termite infestations. The fungal isolate, dose, termite species and individual termite colony may all be factors that determine if there is repellency due to the presence of the fungus, and the degree of repellency. If spores are repellent, there will be less horizontal transmission. Bait formulation additives may be required to overcome the repellency.
[0008] It may be preferable that an entomopathogenic fungus intended for use as a biocontrol agent for termites have an effective, but relatively slow, mode of action. This will allow the fungus to become more widely dispersed throughout the colony before mortality occurs. A highly virulent fungus may only kill the termites in the immediate vicinity of the bait.
SUMMARY OF THE INVENTION
[0009] We have discovered strains of the entomopathogenic fungus of the genus Paecilomyces that are useful for control of infestations by subterranean termites, particularly those belonging to the family Rhinotermitidae, such as the Formosan subterranean termite and native North American subterranean termites. Large numbers of infectious propagules of the fungus can be readily cultured on media that are easily and inexpensively prepared. The entomopathogenic agents of particular interest are blastospores produced by P. fumosoroseus and closely related Paecilomyces spp.
[0010] In accordance with this discovery, it is an object of this invention to provide entomopathogenic fungi, compositions containing such fungi, and methods of using these fungi to kill subterranean termites and to protect wood susceptible to termite damage.
[0011] A specific objective of this invention is to control termite infestations using Paecilomyces spp.
[0012] Another objective of this invention is to provide a biologically-based alternative to currently available, chemical control methods for controlling subterranean termites.
[0013] Another specific objective of this invention is to control termite infestations with a formulation that is composed of an effective dose of infectious propagules of Paecilomyces in a suitable carrier for delivery to termites.
[0014] A further specific objective of this invention is to introduce a method of controlling termite infestations comprising delivery of a formulation of infectious propagules of Paecilomyces in, on, or near a currently or potentially infested structure, tree or plant.
[0015] Yet another specific objective of this invention is to provide a component of termite treatment strategies and formulations that will enhance control and reduce damage by termites. For instance, effective suppression of termite colonies may rely on an integrated pest management (IPM) strategy that would include the use of several strategies such as biological agents, chemicals, appropriate building techniques and physical barriers.
[0016] Other objectives and advantages of this invention will become readily apparent from the ensuing description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIG. 1 is a series of graphs showing the percent mortality of Formosan subterranean termites as a function of the number of days post-exposure to filter paper wetted with various strains of P. fumosoroseus blastospores at either 1×10 6 or 1×10 9 blastospores/ml solution.
[0018] [0018]FIG. 2 is a series of graphs showing the percent mortality of Formosan subterranean termites as a function of the number of days post-exposure to filter paper wetted with various additional strains of P. fumosoroseus blastospores at either 1×10 6 or 1×10 9 blastospores/ml solution.
[0019] [0019]FIG. 3 is a series of bar graphs showing the percent mortality of Formosan subterranean termites as a function of the number of days post-exposure to filter paper wetted with P. fumosoroseus strain ARSEF 3581 blastospores at either 1×10 6 or 1×10 9 blastospores/ml solution.
[0020] [0020]FIG. 4 is a series of bar graphs showing the percent mortality of Formosan subterranean termites as a function of the number of days post-exposure to filter paper wetted with 9-day old blastospores of P. fumosoroseus strain ARSEF 3581 at either 1×10 6 or 1×10 9 blastospores/ml solution.
[0021] [0021]FIG. 5 is a series of bar graphs showing the mean percent mortality of Native subterranean termites as a function of the number of days post-exposure to filter paper wetted with P. fumosoroseus strain ARSEF 3581 blastospores at either 1×10 6 or 1×10 9 blastospores/ml solution.
[0022] [0022]FIG. 6 is a series of bar graphs showing the collective mortality of Native subterranean termite workers exposed to a conidial culture on an agar plate of P. javanicus strain ARSEF 322 and nestmates of the workers to which the fungi were transferred.
[0023] [0023]FIG. 7 shows the collective mortality of Formosan subterranean termite workers directly exposed to conidial culture on an agar plate of either P. javanicus strain ARSEF 322 or P. fumosoroseus strain ARSEF 3581 and nestmates of the workers to which the fungi were transferred.
[0024] [0024]FIG. 8 shows the collective mortality of Formosan subterranean termite workers directly exposed to conidial culture on an agar plate of P. fumosoroseus strain ARSEF 3581 and nestmates of the workers to which the fungi were transferred.
DETAILED DESCRIPTION OF THE INVENTION
[0025] As used herein, the term “termiticide” refers to a material or mixture of materials which induce mortality, disrupt or impede growth, interfere with metamorphosis or other morphogenic functions, effect sterilization, or interfere with reproduction of the targeted termites. The term “controlling” is used herein to mean that the population is reduced, principally through mortality, at a level that is significantly greater than an untreated population. “Significant mortality” is defined herein to mean that the percentage of insects that die within a given period of time after coming into contact with the termiticide is significantly greater than the number of insects not contacted with the termiticide that die during the same period of time. An “effective amount” is used herein in reference to that quantity of entomopathogenic agent necessary to obtain significant mortality in a population or colony of termites. The actual rate amount of agent needed for a particular application will be dependent upon a number of factors, such as the mode of application, the environmental conditions, the particular fungal strain being used, the species of target termite, and the composition of the formulation. The person of ordinary skill in the art would be able to experimentally determine an actual effective amount for a particular situation by observing the success of a control regimen, and then modifying it accordingly. We have found that in petri dish assays described in the Examples, below, effective control can be achieved by causing termites to directly or indirectly come into contact with a substrate treated with a suspension containing from about 1×10 6 to about 1×10 9 viable propagules/ml.
[0026] The fungal entomopathogens of the invention include any of variety of strains of P. fumosoroseus or closely-related species, such as P. javanicus, that are effective in controlling subterranean termites, that is, in causing significant mortality in a population of termites. Exemplary strains of P. fumosoroseus, without limitation thereto, include ARSEF 4480, ARSEF 3581, ARSEF 3878, ARSEF 4489, ARSEF 4491, and ATCC 20874. An exemplary strain of P. javanicus is ARSEF 322. ARSEF accessions are freely available from the U.S. Department of Agriculture, Agricultural Research Service Entomopathogenic Fungus collection, Tower Road, Ithaca, N.Y. 14853-2901.
[0027] The fungal entomopathogens encompassed herein are effective for use against subterranean termite species, particularly those belonging to the family Rhinotermitidae, and more particularly against the Formosan termite ( Coptotermes formosanus ) and native North American termites ( Reticulitermes flavipes ). Other target Rhinotermitidae species of potential economic interest include R. hesperus, and R. virginicus. Unlike the higher termites of the Termitidae family that have bacteria in their guts for digesting cellulosic materials, the Rhinotermitidae and other lower termites rely on gut-dwelling protozoa for this process.
[0028] Infection of termite individuals with the Paecilomyces spp. is effected by application of a control agent comprising fungal propagules directly to termites, to the locus of termites, to material susceptible to termite infestation, or to the locus of material susceptible to termite infestation. Treatment areas may include woody environments such as lumber, structures or buildings constructed at least in part from wood, dead or living plants, particularly trees, forests, orchards or other agricultural fields which are subject to termite attack.
[0029] The preferred propagules of interest are spores (i.e. blastospores), and particularly dessication tolerant blastospores as described by Jackson in U.S. Pat. No. 5,968,808, herein incorporated by reference. The blastospores described by Jackson are produced in a liquid culture medium. Also contemplated by the invention are control agents comprising primarily Paecilomyces spp. blastospores in combination with Paecilomyces spp. conidia and/or mycelia. These may be applied to the treatment area in the form of a recovered culture broth or in combination with a suitable vehicle or carrier that does not substantially interfere with the viability of the fungus.
[0030] Subterranean termites are normally attracted to and reliant upon the presence of moisture; therefore, water is a particularly preferred carrier, although other carriers suitable for use herein include but are not limited to alcohols, ethers, glycols, ketones, esters, and solid carriers such as clays, silicas, cellulosics, rubber, or synthetic polymers. It may also be desirable to incorporate a humectant, such as methylcellulose or polyacrylamide, to maintain the moisture content in the composition. The Paecilomyces-containing pesticidal compositions of this invention may, for example, be formulated as wettable powders, dusts, granules, baits, solutions, emulsifiable concentrates, emulsions, suspension concentrates and sprays (aerosols).
[0031] The fungal entomopathogens of the invention may be applied to, or impregnated into, a bait matrix intended to be placed in bait stations. The matrices that have potential for use in bait stations in accordance with the invention would include solids, semi-solids, or liquids. The bait stations are usually placed at least partially below the soil surface, but may also be completely above ground. It has been found that placement of a bait station in the path of an active mud tube is effective for achieving contact of the bait matrix by the termites. When the station is in the vicinity of a termite colony, termites will preferentially feed on the treated bait, and thereafter transfer the entomopathogen to other members of the colony. The matrix will usually contain a form of cellulose as an attractant. Suitable cellulose-containing materials for use as bait matrices include, but are not limited to paper, paper products (e.g., virgin paper, recycled paper, or a combination of both), cotton linter, cardboard, paperboard, wood, sawdust, wood particles or wood flour, processed or purified cellulose, cellulose derivatives such as cellulose ethers, and including, for example, methylcellulose, hydroxypropylmethyl-cellulose, and hydroxybutylmethylcellulose, or other agricultural fibers. Bait matrices may also contain other organic materials that provide nutrition, attractant or arrestant properties. A particularly preferred bait matrix for use herein is described by Rojas et al. (commonly assigned U.S. patent application Ser. Nos. 09/294,499, filed Apr. 20, 1999, and 09/625,940, filed Jul. 26, 2000), the contents of which are incorporated by reference herein.
[0032] The Paecilomyces spp. entomopathogens described above may be used alone or in combination with other (secondary) termiticides. Suitable secondary termiticides include, but are not limited to, biological controls such as termite growth regulators, and materials or organisms that are toxic to termites (i.e., toxicants) such as chemical insecticides, pathogenic nematodes, other fungi, protozoans, or bacteria. Preferred secondary termiticides are slow-acting (i.e., killing exposed termites after hours, days or weeks), to reduce “avoidance” effects before individuals have infected other members of the colony with the P. fumosoroseus. A variety of slow-acting termiticides are known in the art, and include, for example silafluofen, borates (boric acid, disodium octaborate tetrahydrate), sulfluramid and other fluoroalkyl sulfonamides, avermectin, hydramethylnon, hexaflumuron and other chitin synthesis inhibitors and other acyl ureas, diflubenzuron (Dimilin), azadirachtin, dechlorane (Mirex), diiodomethyl-para-tolyl sulfone (A-9248), fluorosulfonates, imidacloprid, azadirachtin, cyromazine, juvenile hormones and juvenile hormone mimics or analogs such as fenoxycarb, methoprene, hydroprene, triprene, furnesinic acid ethyl and alkoxy derivatives, and pyriproxyfen (Nylar), and the plant Rheuneo jupanic Thunb. Roth. The mortality rate of otherwise faster-acting insecticides may be retarded by microencapsulation or other slow-release formulation. Biological control agents that may be used as secondary termiticides include fungi such as Metarhizium anisopliae, Aspergillus flavus, and Beauveria bassiania, nematodes such as Neoplectana carpocapsae, insect viruses, pathogenic bacteria such as Bacillus thuringiensis and Serratia marcescens, and toxins derived from biological control agents such as B. thuringiensis toxin.
[0033] Optionally, the Paecilomyces-containing compositions may be further formulated with other insect attractants such as pheromones of the target termites or termite extracts containing pheromones or pheromone mimics. Termite pheromones suitable for use herein are generally well-known in the art, and include, for example, (Z,Z,E)-3,6,8-dodecatrien-1-ol, and the aggregation pheromone n-hexanoic acid. The composition may also include one or more additional termite attractants such as food odor attractants or aggregation attractants. Without being limited thereto, suitable food odor attractants are described by Peterson (U.S. Pat. No. 5,756,114), the contents of which are incorporated by reference herein.
[0034] The following Examples are intended only to further illustrate the invention and are not intended to limit the scope of the invention, which is defined by the claims.
EXAMPLES
[0035] Propagation of Paecilomyces Strains
[0036] Fungi used in the following Examples included P. fumosoroseus: ARSEF 3581 (host: Bemisia argentifolli; McAllen, Tex.); ARSEF 4480 ( Bemisia tabaci; Calexico, Calif.); ARSEF 4489 ( Bemisia tabaci; Calexico, Calif.); ARSEF 4491 ( Bemisia tabaci; Padappai, India); ATCC 20874 ( Bemisia tabaci ); and ARSEF 3878 ( Bemisia tabaci; Multan, Pakistan). P. javanicus ARSEF 322 ( Litodactylus leucogaster; Gainesville, Fla.) was also tested.
[0037] Conidia. Stock cultures of all isolates were grown on potato dextrose agar (PDA) for three weeks at room temperatures, cut into 1 mm 2 agar plugs and stored in 10% glycerol at −80° C. Conidial inocula were produced by inoculating Potato Dextrose Agar (PDA; DIFCO) plates with a conidial suspension from frozen stock cultures and growing these cultures at room temperature (˜25° C.) for 2-3 wks. In Formosan subterranean termite bioassays where conidia were tested, conidia were obtained from sporulated PDA plates.
[0038] Blastospores. Blastospores of P. fumosoroseus were produced for termite bioassays as follows. Liquid cultures (100 mL in 250 mL baffled, Erlenmeyer flasks) were grown at 28° C. and 300 rpm in a rotary shaker incubator (INNOVA 4000, New Brunswick Scientific, Edison, N.J., USA). Blastospore precultures were inoculated with a final concentration of 1×10 5 conidia/mL with conidia obtained from sporulated PDA plates of P. fumosoroseus. After three days growth, blastospores obtained from these precultures were used to inoculate production flasks at a final concentration of 5×10 6 blastospores/mL. Blastospore production flasks were harvested after three days growth.
[0039] Spore concentrations were determined microscopically with a hemacytometer. A minimum of triplicate flasks were used for all treatments and all experiments were repeated at least twice.
[0040] Paecilomyces Media Composition
[0041] The basal component of the liquid culture medium contained per liter: KH 2 PO 4 , 2.0 g; CaCl 2 .2H 2 O, 0.4 g; MgSO 4 .7H 2 O, 0.3 g; CoCl 2 .6H 2 O, 37 mg; FeSO 4 .7H 2 O, 50 mg; MnSO 4 .H 2 O, 16 mg; ZnSO 4 .7 2 O, 14 mg; thiamin, riboflavin, pantothenate, niacin, pyridoxamine, thioctic acid, 500 μg each; folic acid, biotin, vitamin B 12 , 50 μg each. Carbon and nitrogen were provided in the medium by addition of glucose (Sigma Chemical, St. Louis, Mo.), 80 g/L, and Casamino acids (vitamin-assay, Difco, Detroit, Mich.), 25 g/L. All media had an initial pH of 5.5 and pH was uncontrolled during culture growth. Glucose stock solutions were autoclaved separately.
[0042] Desiccation of P. fumosoroseus Blastospores
[0043] Blastospores were air-dried using two filter aids; diatomaceous earth or calcined kaolin clay. Experiments designed to determine the repellency of spore preparations to termite tunneling were conducted with spore/diatomaceous earth preparations. All other experiments were conducted with spore/clay formulations. All air-dried P. fumosoroseus spore preparations were obtained by mixing liquid cultures of P. fumosoroseus, which consisted primarily of blastospores, with either diatomaceous earth (HYFLO, Celite Corp., Lompoc, Calif.) or calcined hydrophilic kaolin clay (Surround, Engelhard Corp., Iselin, N.J., USA). These filter aids were added to whole cultures of P. fumosoroseus at a rate of 1 gram diatomaceous earth or kaolin clay for each 2×10 10 blastospores. Spore/filter aid preparations were vacuum-filtered on filter paper (Whatman No. 1) to remove the excess liquid and the filter cake obtained was dried overnight in a humidity-controlled drying chamber (RH>60) to 2-5% moisture. The moisture content of the dried blastospore preparations, expressed as (wet weight-dry weight)/wet weight×100, was determined with a moisture analyzer (MARK I, Denver Instruments, Tempe, Ariz., USA). Dried blastospore preparations were stored under vacuum in nylon/EVOH/polyethylene bags with a desiccant (1 g silica packet; #Z16356-Z, Sigma, St. Louis, Mo.) at 4° C. The viability of dried P. fumosoroseus spore preparations was determined using a previously described spore germination assay [Jackson, M. A. et al. (1997) Mycol. Res. 101:35-41, herein incorporated by reference] for diatomaceous earth preparations and by plate counting for spore preparations containing kaolin clay.
[0044] Collection of Termites
[0045] Formosan subterranean termites ( Coptotermes formosanus Shiraki) and Native subterranean termites ( Reticulitermes flavipes ) were obtained from colonies at the Southern Regional Research Center, City Park and the University of New Orleans which are all located in New Orleans, La. Multiple colonies of termites were chosen to prevent colony vitality biasing of data. Each colony represented one replicate in each experiment. Bucket traps were established to allow access to termites. Twenty workers of at least 3rd instar (as determined by size) were used in each of the replicates.
[0046] Exposure of Termites to Fungi
[0047] For Mortality Determination Only: Either 10 or 20 Formosan subterranean termites from each of four colonies were allowed to walk on fungal cultures for 5 minutes. These workers were then transferred to 100×15 mm Petri dishes (Falcon, Franklin Lakes, N.J.) which contained Whatman #4 filter paper (Maidstone, England), dampened with sterile water (Solution 2000 Water Purification System, Solution Consultant Inc., Jasper, Ga.).
[0048] For Transferability and Mortality Determination: Ten Formosan subterranean termites from each of four colonies were allowed to walk on fungal cultures for 5 minutes. These workers were then transferred to 100×15 mm Petri dishes (Falcon, Franklin Lakes, N.J.) which contained Whatman #4 filter paper (Maidstone, England), dampened with sterile water (Solution 2000 Water Purification System, Solution Consultant Inc., Jasper, Ga.), and 10 unexposed worker termites from the same colony as those exposed to the fungus.
[0049] Incubation of Exposed Termites and Controls
[0050] All plates containing termites were then placed in an unlit incubator at 25° C. and 99% humidity for the duration of the experiment. Control plates were incubated as described above and contained the same number of termites as the test plates, none of which had been exposed to fungal cultures. All work prior to incubation was conducted under a laminar flow hood (NuAire, Plymouth, Minn.).
Example 1
[0051] Mortality of FST by P. fumosoroseus (Four Strains) Blastospores
[0052] Twenty FST ( Coptotermes formosanus Shiraki) workers from each of four colonies were incubated on filter paper that was wetted with 500 μL of a 1×10 6 or 1×10 9 blastospores/ml solution of P. fumosoroseus strains ARSEF 4480, ARSEF 4489, ARSEF 3878, or ATCC 20874. Controls were exposed to filter paper wetted with water only. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 1.
Example 2
[0053] Mortality of the FST by P. fumosoroseus (Two Strains) Blastospores
[0054] Twenty FST ( Coptotermes formosanus Shiraki) workers from each of four colonies were incubated on filter paper that was wetted with 500 μL of a 1×10 6 or 1×10 9 blastospores/ml solution of P. fumosoroseus strains ARSEF 3581 and ARSEF 4491. Controls were exposed to filter paper wetted with water only. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 2.
Example 3
[0055] Mortality of the FST by P. fumosoroseus Strain ARSEF 3581 Blastospores
[0056] Twenty FST ( Coptotermes formosanus Shiraki) workers from each of four colonies were incubated on filter paper that was wetted with 500 μL of a 1×10 6 or 1×10 9 blastospores/ml solution of P. fumosoroseus strain ARSEF 3581. Controls were exposed to filter paper wetted with water only. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 3.
Example 4
[0057] Mortality of the FST by P. fumosoroseus Strain ARSEF 3581, Blastospores Stored as Whole Cultures for 9 Days at 4° C.
[0058] Twenty FST ( Coptotermes formosanus Shiraki) workers from each of four colonies were incubated on filter paper that was wetted with 500 μL of a 1×10 6 or 1×10 9 blastospores/ml solution of P. fumosoroseus strain ARSEF 3581 as in Example 3, but the blastospores were stored at 4° C. for an additional 9 days. Controls were exposed to filter paper wetted with water only. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 4.
Example 5
[0059] Mortality of the Native Subterranean Termite by P. fumosoroseus Strain ARSEF 3581 Blastospores
[0060] Twenty Native Subterranean termites ( Reticulitermes flavipes ) workers from each of four colonies were incubated on filter paper that was wetted with 500 μL of a 1×10 6 or 1×10 9 blastospores/ml solution of P. fumosoroseus strain ARSEF 3581. Controls were exposed to filter paper wetted with water only. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 5.
Example 6
[0061] Mortality of the Native Subterranean Termite by P. javanicus ARSEF 322 Conidia
[0062] Ten Native Subterranean termite ( Reticulitermes flavipes ) workers from each of four colonies were allowed to walk on a conidial culture of P. javanicus ARSEF 322 on agar plates for 5 minutes. The exposed subjects were then incubated with an equal number of nest-mates on filter paper that was kept moist with water. Controls were exposed to filter paper wetted with water only. The percent mortality as a function of days post-exposure is shown in FIG. 6.
Example 7
[0063] Transferability and Mortality of FST by Paecilomyces spp. Conidia
[0064] Ten FST workers from each of 4 colonies were allowed to walk on a conidial culture of either P. javanicus ARSEF 322 or P. fumosoroseus strain ARSEF 3581 on an agar plate for 5 minutes. The exposed subjects were then incubated with an equal number of nest-mates on filter paper that was kept moist with water. Controls were allowed to walk on uninoculated agar then incubated on filter paper that was kept moist with water. Mortality rates in excess of 50% indicate that the fungus was transferred from the exposed workers to nest-mates that were not directly exposed to the fungus. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 7.
Example 8
[0065] Transferability and Mortality of FST by P. fumosoroseus Conidia
[0066] Ten FST workers from each of 4 colonies were allowed to walk on a conidial culture of P. fumosoroseus strain ARSEF 3581 on an agar plate for 5 minutes. The exposed subjects were then incubated with an equal number of nest-mates on filter paper that was kept moist with water. Controls were allowed to walk on uninoculated agar and then incubated on filter paper that was kept moist with water. Mortality rates in excess of 50% indicate that the fungus was transferred from the exposed workers to nest-mates that were not directly exposed to the fungus. The percent mortality as a function of days post-exposure for each trial is shown in FIG. 8.
Example 9
[0067] Control of FST Using Dust, Spray, and Bait Formulations Containing P. fumosoroseus
[0068] This experiment was performed to test formulations containing P. fumosoroseus that are examples of dusts, sprays, and baits. The mortality of FST was determined as a function of time after treatment. Termites from 4 colonies were treated to reduce errors caused when only a single colony is used. Except as indicated, the procedures and conditions of this experiment were the same as those indicated for Examples 1-8, above.
[0069] The experiment consisted of 13 treatments×4 colonies×10 termites (9 workers and 1 soldier) per petri plate for a total of 52 plates (520 termites total: 130 from each of 4 colonies). Plates were stored in a plastic container with a lid. The container was lined with wet paper towels to maintain 100% RH, and was kept in an incubator at 28° C. in the dark. The results are shown in Table I, below.
[0070] Materials:
[0071] A P. fumosoroseus 3581 blastospore suspension grown in liquid culture that contained 1.6×10 9 cfu/ml (Treatments 9E & 9J).
[0072] [0072] P. fumosoroseus 3581 dried blastospores in a diatomaceous earth (1 part) and rice flour (9 parts) mixture that contained 3.4×10 9 cfu/g (Treatment 9A).
[0073] A P. fumosoroseus 3581 conidial suspension (conidia washed from Sabouraud Dextrose Maltose Agar plates with sterile 0.01% Tween 80 solution) that contained 2.4×10 7 cfu/ml (Treatments 9H & 9L).
[0074] [0074] P. fumosoroseus 3581 conidia that were grown on rice flour in a vented polypropylene bag for 7 weeks at 25° C. with a daily 12-h photoperiod. The P. fumosoroseus -infested rice flour contained 7.7×10 7 cfu/g (Treatment 9C).
[0075] The diatomaceous earth was Hyflo SuperCel. Rice flour was autoclaved twice before use. Spent liquid media was filtered to remove fungal propagules for use as a control. Filter paper was Whatman #1, 8.2-cm diameter. Tween 80 (Polysorbate 80) was obtained from Uniqema R&T, Wilmington, Del.
[0076] Termite mortality at 5 and 10 days was determined and the number of termites located on treated and untreated halves in the bait experiment (Treatments 9J-9M) were recorded at days 1 and 2.
[0077] Formulations:
[0078] Dusts
[0079] Dusting procedure: For treatments 9A-9D, 10 termites from each colony were dusted with a small amount of the treatment by shaking gently. The termites were transferred to a petri plate that contained 1 sheet of filter paper dampened with 1.0 ml of sterile water.
[0080] Sprays
[0081] For treatments 9E-9I, 10 termites from each colony were sprayed with each treatment formulation. The sprayed termites were then transferred to a petri plate that contained one sheet of filter paper moistened with 1.0 ml sterile water.
[0082] Baits
[0083] For treatments 9J-9M, 0.5 ml of blastospore suspension or conidial suspension was applied to a one-half sheet of paper in a petri plate. A 0.5-ml volume of sterile water was applied to another one-half sheet placed in the same dish. The sheets were actually cut a little less than in half in order to leave a gap of about 2 mm between them. Ten termites from each colony were exposed to each treatment. Controls consisted of filtrate from blastospore suspension (fungal propagules removed) and a 0.01% Tween 80 solution.
Example 10
[0084] Evaluation of Termite Repellency by P. fumosoroseus
[0085] The possibility of a termiticide being repellent to the target insect and creating an avoidance response is a concern. The repellent properties of P. fumosoroseus isolate 3581 toward FST, or the lack thereof, were evaluated by the procedure of Staples and Milner [ Sociobiology 36(1): 133-148, (2000)] which was modified by the use of laboratory-grade sand instead of river sand and by the use of 5% agar instead of 2% agar. The increase of agar concentration improved the ability of the termites to tunnel into the agar layer.
[0086] In brief, the referenced agar-tube method for quantifying the repellency of a fungus to termites involved a 35-mm deep layer of sand treated with the fungus and placed in the bottom of a 50-ml plastic centrifuge tube. The sand was topped with a 32-mm layer of water agar. The sand was dampened with either water or a suspension of fungal propagules in water to a final water content of about 10% to 12%. A 0.04-g strip of filter paper was placed on top of the agar as a food source. A total of 50 FST termites (40 workers and 10 soldiers) were added to the top of the agar. The test consisted of three tubes per treatment. Three termite colonies (one colony in each of the three tubes) were used in order to reduce error due to differences in colony response to exposure to the fungus. Both blastospores and conidia of P. fumosoroseus were tested in the form of liquid and solid treatments and the appropriate untreated controls were included in the experiment. The depth of penetration of the termites into the sand substrate was measured at 2, 3, and 7 days and the results were expressed as a percentage of the total depth of the sand layer (Table II). The concentrations of the fungus in the damp sand substrate were as follows: blastospores in liquid treatment=4.9×10 7 cfu/g; blastospores in solid treatment=4.8×10 8 cfu/g; conidia in liquid treatment=1.9×10 6 cfu/g; and conidia in solid treatment=1.2×10 7 cfu/g.
[0087] It may be concluded from the data in Table II that blastospores and conidia of P. fumosoroseus isolate 3581 applied as a suspension in water to sand did not repel the termites. The termites tunneled into the treated sand and reached the bottom of the tube by 7 days as they did in untreated sand. However, when blastospores and conidia were incorporated in the sand as dry preparations (blastospores in diatomaceous earth and conidia grown on rice flour) and the sand/fungus mixture was dampened with water, repellency occurred in both treatments. The repellency was more pronounced in the case of the conidia/rice flour preparation. In contrast, the termites had completely penetrated the untreated sand by the second day of the experiment.
[0088] The results of this experiment suggest that repellency may be minimized by the type of preparation used to apply the fungus (for example, liquid or solid preparations) and by the particular propagules chosen (for example, blastospores or conidia). The concentration of the fungus in the soil is another factor which may allow control of the degree of repellency of the fungus to termites.
TABLE I Mortality of FST Caused by Dust, Spray, and Bait Formulations Containing P. fumosoroseus 3581 Termite Mortality, % (Days after treatment) Example Treatment 5 10 DUSTS 9A P. fr. blastospores in diatom. earth/rice flour 73 100 9B Control: ditom. earth/rice flour 13 35 9C P. fr. conidia in infested rice flour 100 100 9D Control: rice flour 3 8 SPRAYS 9E P. fr. blastospore suspension 100 100 9F Control: filtrate from blastospore suspension 5 38 9G Control: liquid media 20 30 9H P. fr. conidia washed from plates 83 100 9I Control: 0.01% Tween 80 5 8 BAITS 9J P. fr. blastospores on filter paper 83 100 9K Control: filtrate from blastospore suspension 20 73 9L P. fr. conidia on filter paper 65 100 9M Control: 0.01% Tween 80 0 5 # were on untreated paper) as did the conidia (28% were on the treated and 52% were on the untreated paper) (Data not shown in table).
[0089] [0089] TABLE II Repellency of Termite by P. formosoroseus % Penetration of Treated Sand Treatment 2 Days 3 Days 7 Days Liquid treatments Blastospores (liquid culture) 79 90 100 Conidia (washed from plates) 61 97 100 Control (water) 52 67 100 Solid treatments Blastospores in diatomaceous earth 27 33 89 Control (diatomaceous earth) 100 100 100 Conidia in rice flour 7 7 7 Control (rice flour) 100 100 100
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The entomopathogenic fungus Paecilomyces fumosoroseus and certain related species, such as P. javanicus are useful for controlling infestations by subterranean termites, particularly those belonging to the family Rhinotermitidae. The family Rhinotermitidae includes two species of subterranean termites having extremely high economic importance in the United States; namely the Formosan subterranean termite ( Coptoterimes formosanus Shiraki), and the native (North American) subterranean termite ( Reticulitermes flavipes ). Large numbers of infectious propagules of the fungus, such as blastospores and conidia can be readily cultured on media that are easily and inexpensively prepared and incorporated into formulations for controlling termites. These fungi are useful for protecting living trees, plants, wood, wood structures, and other cellulosic materials susceptible to termite infestation and damage.
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TECHNICAL FIELD
The invention relates to artificial intelligence (AI) production systems, and more particularly, to a method for optimizing the pattern-matching phase of a cyclic, rule-based, data-sensitive AI production system.
BACKGROUND
It should be appreciated that the artificial intelligence branch of computer science has exhibited explosive growth in recent years. One facet of AI has been concerned with the modeling and use of inference systems. Such inference systems exploit the computer science formalism termed "rewrite" or "production" systems. At a minimum, a rewrite or production system includes an alphabet, an initial set of strings (axioms) defined over the alphabet, and a set of production or rewrite rules from which new strings (theorems) can be obtained.
Peter Jackson, "Introduction to Expert Systems", Addison-Wesley Publishing Co., copyright 1986, pp. 29-51 and 126-141, points out that an AI production system comprises a rule set (sometimes called production memory), a rule interpreter that decides how and when to apply the rules, and a working memory that holds data, goals, and intermediate results.
Brownston et al, "Programming Expert Systems in OPS5", Addison-Wesley Publishing Co., copyright 1985, pp. 4-31, contrast a rule-based production computational model with that of a procedural model. More particularly,
Brownston describes a production system as an executable set of production rules in which each rule in such a system represents an ordered pair of a condition (state set) and action statements. This leads to Brownston's characterization of a production system as an unordered finite sequence of data-sensitive production rules.
______________________________________Brownston's ComparisonProduction System Model Procedural Modelof Computation of Computation______________________________________Program Description: Program Description:A description of data An ordered list ofexpressed as objects, instructions written inattributes, and values, a language with a well-and an unordered finite defined syntax andsequence of rules that semantics. The list hascan be referenced by the a specified beginning.data. Each rule consists The language includes aof a condition/pattern stop/halt instruction orpart and an action part. punctuation whose meaning is to cease instruction execution.Execution: Execution:Requires maintenance of a The instructions areglobal data base containing directly executable.the problem description and The first instructionany modifications, in the list initiatesadditions, or deletions execution. After this,thereto and a recognize, execution proceeds inresolve, act (RRA) or match, sequence punctuated byselect, execute cycle. The conditional branchescycle: until a stop or halt instruction is encountered.(a) identifies that subsetof rules having acondition or pattern partmatching the data,(b) selects at least onerule from the identifiedsubset of rules accordingto an extrinsic protocol,and(c) executes (fires) theaction prescribed by theaction part of theselected rule includingmodification to the database.______________________________________
In addition to Jackson and Brownston, reference should also be made to:
(1) Miranker, "TREAT: A Better Match Algorithm for AI Production Systems", Proceedings of the AAAI-87 Sixth National Conference on Artificial Intelligence, Vol. 1, July 13-17, 1987, pp. 42-47.
(2) Miranker, Dept. of Computer Science, University of Texas at Austin, Report TR-87-03, January 1987.
(3) Forgey, "OPS5 Users Manual", CMU-CS-81-135, copyright 1981.
(4) Forgey, "Rete: A Fast Algorithm for the Many Pattern/Many Object Pattern Match Problem", Artificial Intelligence, Vol. 19, copyright 1982, pp. 17-37.
(5) Schor et al, "Advances in Rete Pattern Matching", Proceedings of AAAI '86.
(6) Chambers et al, "Distributed Computing", Academic Press, copyright 1984, pp. 10-19.
(7) Aho et al, "Compilers: Principles, Techniques, and Tools", Addison-Wesley Publishing Co., copyright 1986, pp. 608-632.
Brownston, Miranker, Forgey, and Schor describe pattern-driven, forward-chaining production systems using a matching-rule, select-rule, execute-rule cycle based on the OPS5 AI language. Furthermore, these references point out that the process of many data-object/many pattern matching is the most computationally intensive phase in the production system control cycle.
The references teach several techniques for reducing the computational intensity of the pattern-matching phase. First, advantage can be taken of the temporal redundancy of the data objects resident in working memory. That is, the set of objects over which the pattern portions of the rules are compared can be limited to those objects in working memory which have been either created or modified since the last cycle. Second, the many object/many pattern comparison can be systematized through use of sorting or dataflow-like processing networks. While there are other comparison algorithms, such as Miranker's TREAT, the best known comparison method having these attributes is the RETE algorithm ascribed to Forgey.
Forgey and Jackson discuss the RETE pattern/object matching method used in the AI production system control cycle. This method includes:
(a) compiling the condition elements of the pattern portion of a rule into an augmented data flowgraph (see Aho and Chambers) or a comparison sorting network (Forgey);
(b) comparing each object with conditions of the pattern as expressed in the compiled network over a set of nodes (alpha-nodes) that each test one object at a time;
(c) passing tokens indicative of a match from antecedent nodes to descendant nodes (beta-nodes) joined on a pattern-determined basis, comparing each token received at a descendant node, and passing tokens on to descendants in turn until the paths through the flowgraph are traversed; and
(d) maintaining a list of instantiations satisfying the match conditions expressed at each node.
In the remainder of this specification, the terms MAKE and CREATE, MODIFY and UPDATE, and REMOVE and DELETE will be used interchangeably. Also, the RECOGNIZE, RESOLVE, and ACT phases of the AI production system control cycle serve as synonyms for MATCH, SELECT, and EXECUTE.
SUMMARY OF THE INVENTION
It is an object of this invention to devise a method for optimizing the pattern-matching phase of a cyclic, rule-based, data-sensitive production system.
It is a related object to devise a method in which a path through a RETE network used during the comparison phase can be traced, thereby minimally invoking the comparison, token passing, and recording aspects of the RETE algorithm.
It is yet another object to devise a method utilizing the path for deletion of an object, including removal of any counterpart instantiations recorded at the lists maintained by various nodes through which a token has passed.
It is a further object to devise a method in which alteration of objects by a MODIFY command is accomplished as a function of the DELETE and MAKE commands and their associated processes.
The aforementioned objects are satisfied by the method steps executed during the pattern-matching portion of the matching, selection, and execute cycle of an AI production system comprising: (a) compiling a RETE network of the condition elements of the pattern portion of the rule being matched, the join nodes of said network being grouped in a pattern-determined associative manner; and (b) applying those data objects created or modified in the immediately preceding cycle to said RETE network.
The method includes the further steps at each node of: (b1) maintaining a list of instantiations satisfying the match conditions expressed at that node, (b2) passing tokens to descendant nodes upon an object/pattern comparison match, (b3) maintaining pointers to all ancestor nodes through which the token for each object passed, and (b4) traversing said pointers as a path for avoiding those RETE node pattern/object matchings redundant between a previously matched object and an object being processed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a directed graph RETE network produced during compilation of the pattern portion (left-hand side) of the sample rule.
FIG. 2 shows a block diagram of the prior art logical machine as executed on any general purpose, stored program-controlled digital computer upon which the method of the invention may be practiced.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In order to enhance appreciation for the method of this invention, a description of the generation, function and use of the RETE comparison algorithm and supporting data structures according to the prior art will be set out. Following this is a discussion of the invention utilizing the data structures. Lastly, a pseudo-code implementation and description is presented.
Classic RETE Processing
Reference should be made to previously cited Forgey, Brownston, and Miranker publications for implementation and additional details. The example discussed is a scheduling application involving parts and machines.
Suppose there is a company that manufactures parts, that the company has two machines A and B, that there are two types of parts (P and Q) manufactured by the company, and that to complete a part of type P, machine A and then machine B must be used; while to complete a part of type Q, machine B and then machine A must be used.
Suppose there is interest in a computer program that does production scheduling (deciding which parts should be routed to which machines) as the work progresses.
Machines will be represented by records matching the following data declaration:
______________________________________ Declare machine, type, state.______________________________________
Here "type" and "state" are attributes or fields in the machine record. "Type" may have the value "A" or the value "B"--representing the type of machine, and "state" may have the value "AVAILABLE" or "BUSY"--representing the current availability of the machine to accept a part to begin processing.
In this example, data-driven production system techniques as well as terminology common to such systems are used. Specifically, many records will be able to co-exist, each satisfying the declaration above. The collection of all records satisfying any one such declaration will be called a "class". Each individual record will be called a "class member". The overall collection of all class members from all classes will be called "working memory".
Each part (partially or fully complete) will be represented in the system by class members (records) satisfying the following declaration:
______________________________________ Declare part, type, state, next-machine-needed.______________________________________
Here "type" can have the values "P" or "Q", while "state" must be "in-process", "waiting", or "complete", representing that a part must at any instant be either in the process of being machined, or waiting for a machine, or through with all needed machining.
Suppose also that occasionally the company gets express orders that must be expedited. Such orders are of very high priority, and although the machining of a nonexpress part will not be interrupted to make the machine available for an express part, the company's policy is that while there is an express part in the system that will need a machine in the future, that machine will not start any nonexpress work--thus increasing the likelihood that the machine will be available or near becoming available when it is needed for an express part. The declaration for a class member that would represent an express order might look like the following:
______________________________________ Declare express-order, part-type, state, array-of-all-machines-needed, index-of-next-machine-needed.______________________________________
Using data-driven, forward-chaining, condition-action rules (or productions) to encode the routing of parts to machines, one rule in the computer program might look like the following when paraphrased in English:
______________________________________Sample-rule:Whenthere is a machine - which shall be called Msuch that M is availableand there is a part - which shall be called Osuch that the part is waiting for its nextmachining step andthe next machining step required for O must bedone on the machine Mand there are no express parts that satisfy boththe part is not complete, i.e., it is waitingor in-process andthe part will need machine M before it iscompleteThen take the following actions:change the state of M to BUSYchange the state of O to IN-PROCESSroute the part O to the machine M for processing.______________________________________
The list of conditions between the `When` and the `Then` in the rule is called the antecedent or left-hand side (LHS) of the rule. The actions to be taken when the LHS is satisfied by some list of class members is called the consequent or right-hand side (RHS).
There would be many other rules in such a system, and there would be a method for notifying the computer program whenever a machine completed its work on a part.
Referring now to FIG. 1, there is shown a RETE network for the LHS of the Sample-Rule. All arcs are directed and are considered as pointing down in the above picture. RETE processing starts at the top nodes (class anchors) and flows downward through the network. The nodes marked MACHINE, PART, and EXPRESS-ORDER are, respectively, anchors for queues of all machine, part, and express-order class members that exist in the program at that point in time.
Changes to machine, part, or express-order class members can be of several kinds. New members can be created, representing new objects that the system should consider in routing parts to machines. Class members can be destroyed, representing the deletion of some object from participation in the system. For example, when a part is shipped to a purchaser, it might be natural to delete the class member representing that part from the system, as it should no longer be considered in any decisions about scheduling. Changes can also be made to existing class members. Different values are assigned to the attributes of the class member. This is done to represent changes in state, etc.
Each time a change is made to working memory that change is passed through the RETE network. In rough terms, the central nodes of the network fragment in FIG. 1 correspond to tests that must be performed to determine what lists of class members satisfy all the conditions in the LHS of the Sample-Rule above. Class members arranged in lists are tested at a node to determine which lists satisfy the corresponding conditions and, for each node, summary information is retained in a queue based at that node. Usually, the retained information indicates which lists of class members passed the test associated with the node.
The nodes labeled AVAILABLE?, WAITING?, and NOT-COMPLETE? are called alpha-nodes. Alpha-nodes correspond to tests that only mention a single class member. These nodes have only one incoming arc in the RETE network.
The nodes labeled PART-NEEDS-MACHINE? and MACHINE-RESERVED-FOR-EXPRESS? are called beta-nodes. In this RETE network, the beta-nodes all have two incoming arcs and correspond to tests that determine whether a list of several class members satisfies a condition. For example, the node labeled PART-NEEDS-MACHINE? corresponds to a test that determines whether a pair of class members, the first a part and the second a machine, is such that the next-machine-needed field on the part class member is identical to the type filed of the machine class member. In other words, when given a part and a machine, the node determines whether the part needs to go to that machine next.
If a pair (or, in general, a list of any length) of class members satisfies a test, that fact is recorded in a control block which shall be called a Satisfaction Block (SB). The SB is placed in a queue that is anchored at the RETE node and becomes a record of what lists of objects satisfied the conditions associated with that node. The declaration for a simple SB might look like the following:
______________________________________ Declare satisfaction-block, next-SB-in-queue, list-of-class-members;______________________________________
where the specified list-of-class-members field indicates a list of class members which together satisfy the test associated with the node.
Lists of objects that satisfy the conditions associated with a node are candidates that need to be considered for satisfaction of later conditions. To make all the needed tests, while restricting consideration to just those lists of class members that have satisfied all earlier tests, a computational strategy is adopted that pushes tokens through the RETE network (top to bottom when the network is drawn, as in FIG. 1). A token represents a change to some SB and reflects processing that must be done at a successor node. Tokens might satisfy the following declaration where the phrases following the `/*` on any line are comments:
______________________________________Declare token,change-type, /* MAKE or DELETElist-of-class-members, /* list of one or more class /* membersnode, /* identifies node where /* tests will be attempteddirection; /* ancestor that passed the /* token is LEFT or RIGHT of /* the node in the token______________________________________
The declaration of a token includes a direction field which can be set to have one of two values, LEFT or RIGHT. It shall be assumed that all the RETE networks under discussion satisfy the following principles:
A node with only one incoming arc is always viewed as having its one ancestor as a left ancestor.
Where a node has two ancestors (a beta-node) and each ancestor is an alpha-node or is an anchor to a class, then one ancestor can be arbitrarily picked as the left ancestor, while the other will be the right.
Where a beta-node has one ancestor that is a beta-node, then that ancestor shall be called the left ancestor, and the other ancestor (which in the example and in most implementations must be an anchor or alpha-node) becomes the right ancestor.
The use and flow of tokens are illustrated by examining the processing that would take place in the sample RETE network of FIG. 1. Suppose the process is started with an empty working memory. The RETE network of FIG. 1 does not contain any satisfaction blocks. Further, suppose that during initialization of the execution of the program containing the rule above, the first machine class member is created, representing machine A. Since there is no work yet for the machine to do, the state field on the class member would be set to AVAILABLE.
For each successor in the RETE network of the machine anchor node, a token would be created that contains a list of one class member--the new machine class member--in its list-of-class-members field. In the current example, there is only one node that is a successor of the machine anchor node. Thus, only one token would be generated, and it would point to the new machine for its list-of-class-members field. It would point to the AVAILABLE? node for its node field, and it would specify that the token arrived at the AVAILABLE? node from a LEFT ancestor. The token would contain MAKE in its CHANGE-TYPE field, indicating that the new class member was just created.
Typically, if there are many tokens generated at once, they are placed on a stack and processed one at a time. In this simple case, only one token has been generated, so the processing for that one token would immediately proceed. (Typically, the token would be pushed on the token stack but soon thereafter would be popped off.)
This processing done at the node would include executing the test associated with the node for the machine (class member) in the token. In this case, the newly created machine would be tested to see whether its state field listed it as available--which it would be. Thus, the test associated with the node would be passed and several actions would be taken. First, a Satisfaction Block would be created to record that the list of class members in the token passed the test. In this case, the new SB would point to the one new machine class member. Second, new tokens with change-type of MAKE would be generated, one for each successor of the AVAILABLE? node. Again, in this simple case, there is only one successor to the AVAILABLE? node so a token is stacked that specifies (a) machine A, (b) the PART-NEEDS-MACHINE? node, and (c) LEFT.
Again, since there is only one node on the stack, processing for that node immediately proceeds. However, a list of a machine and a part is required to satisfy the PART-NEEDS-MACHINE? node, and there are no parts in existence yet. Thus, there is no more processing that can be done at this time, so control is returned back to the application.
Suppose that the next action taken by the application during this initialization phase is to create the second machine; namely, machine B. As before, a token would be generated to cause testing at the AVAILABLE? node to determine whether this machine is available--which it would be. An SB is created so that there are now two SBs in the queue off the AVAILABLE? node. Since nothing more can be done, control (as before) returns to the application.
Suppose that the application begins normal operation, and scheduling for the first part is to start. The application makes a part class member to represent the existence of the first part, a type P part that is waiting to be machined. Since type P parts must first be machined by machine A, the part's NEEDS-MACHINE field is set to A. Again, a token with change-type of MAKE is generated, indicating this change. The token would point to the new part, specify the WAITING? node, and the left direction.
Processing of the token at the WAITING? node would discover that the part was indeed waiting, so an SB would be created and enqueued off the node and a new token would be created (and pushed onto the stack), indicating that this new part needs to be tested at node PART-NEEDS-MACHINE? where the arrival is from the right.
With only one token on the stack, it is popped off and processing for that token proceeds immediately. A machine and a part are now needed to perform the test associated with the condition at a beta-node (the PART-NEEDS-MACHINE? node). There are two machines, A and B, which have previously arrived in tokens at the PART-NEEDS-MACHINE? node. This fact is recorded by the existence of two SBs enqueued off the AVAILABLE? node, which is the left ancestor of the current node. Thus, a loop is executed that walks through all SB blocks off the AVAILABLE? node.
For each such SB, the test is performed at the PART-NEEDS-MACHINE? node to determine if the new part (of type P) needs the machine in the SB for its next machining step. If the test (PART-NEEDS-MACHINE?) fails, then no additional action is taken. If the test passes, then a new SB is created and enqueued off the PART-NEEDS-MACHINE? node. In this case, the test of the type P part with machine B fails, and the test with machine A passes. Thus, an SB with a list of class members comprised of machine A and the new type P part is enqueued off the PART-NEEDS-MACHINE? node, and a token representing this change to PART-NEEDS-MACHINES?'s SB queue is generated for the one successor of this node. The change made to PART-NEEDS-MACHINE?'s SB queue is the creation of a new SB. Thus, the new token is a MAKE token, and its list of class members includes the A machine and the new P part.
PART-NEEDS-MACHINE? is an example of a positive beta-node. When a MAKE token arrives at such a node from one direction, the list of class members in the token is successively augmented with the list of class members from each SB off the predecessor node in the opposite direction. For each such SB, the test for the current node is performed using the augmented class member list. A passed test causes more tokens to be generated--one for each successor node. These new tokens are MAKE tokens that represent new candidates at successor nodes.
This token is popped off the stack, having arrived at the MACHINE-RESERVED-FOR-EXPRESS? node from the left. This node is a negative beta-node. Unlike positive beta-nodes, the output of a negative beta-node is not an augmented token. A token arriving at a negative beta-node from the left includes a list of class members. This same list is either passed intact to all successor nodes, or it is stopped altogether.
The list is passed on (in tokens) if no test passes at this node involving this class member list augmented by any one of the lists in the right ancestor's SB queue. This list is stopped and not passed to any successor if some test passes at this node when the arriving list is augmented in turn by each of the lists from the right ancestor's SB queue.
Negative beta-nodes are often discussed in the following terms. Class member lists that arrive from the right will stop class member lists arriving from the left from passing through. Thus, a negative beta-node is much like a gate, where the things arriving from the right (according to what tests pass and fail) determine whether things arriving from the left will pass through.
It should be noted that the arrival from the right of a DELETE token (indicating the deletion of an SB from the right ancestor's queue) at a negative beta-node can cause creation of a new SB at the negative beta-node and the corresponding generation of MAKE tokens for all successors of the negative beta-node. This happens when the arriving token indicates deletion of the only SB in the right ancestor's queue that was stopping some SB in the left ancestor's queue. Likewise, a MAKE token arriving from the right can stop an SB that is in the negative beta-node's SB queue, and the MAKE token can cause the removal of an SB and the generation of DELETE tokens for all successors.
In this example, the right ancestor of the MACHINE-RESERVED-FOR-EXPRESS? node is the NOT-COMPLETE? node. There are no express orders, so there can be no express orders with the part not complete. Therefore, there is nothing in NOT-COMPLETE?'s SB queue, and there is nothing that will stop any list of class members (in a token) arriving from the left from passing on through. Thus, arrival of a MAKE token from the left causes a new MAKE token to be generated and passed to the production node.
There is only one production node shown. However, in a real RETE network, there is one production node for each rule. Whenever a token arrives at a production node, the arrival indicates some change to the conflict set for that rule. A MAKE token arriving at a production node indicates that a new instantiation should be created. A DELETE token arriving indicates that an existing instantiation should be eliminated.
In this example, the arrival of the MAKE token at the production node indicates that a new instantiation should be made. Indeed, the pair of class members consisting of machine A and the one part of type P satisfies the conditions of the Sample-Rule based on all the class members that exist at this time. Thus, this one instantiation would normally become a candidate for firing with all other instantiations of other rules. If the rule did fire, then the action part of the rule would change the status of both the P type part and of machine A. Those changes, when pushed through the RETE network, would invalidate this on instantiation to Sample-Rule.
Next, the RETE processing is examined in more detail for this case. As expressed before, this example merely illustrates the prior art.
Suppose that the single instantiation is selected and Sample-Rule does fire. The first action taken is to change the status of machine A to BUSY. This change in machine A's state field with the classic RETE algorithm would be treated as a deletion of the old machine class member, followed by the creation of a new machine class member that is identical to the old one except for the altered value in the state field--the new value being BUSY.
If the machine A class member is deleted, then before the class member is destroyed, a DELETE token is created for the AVAILABLE? node with the token pointing to the machine A class member. As always, the token is stacked with any other tokens. When popped and processed for the AVAILABLE? node, the test associated with the AVAILABLE? node is repeated to determine whether the class member passed or failed the test when it was created. If the current test passes (or fails), then the original test must have likewise passed (or failed, respectively) when the MAKE token was processed.
If the earlier test did fail, there was no additional RETE processing generated by the token. No SB block was made, and no new tokens were spawned. Thus, there is nothing more that need be done now, as there are no descendant references in the RETE network that must be removed to reflect deletion of the class member.
If the earlier test passed, then there must be a record of the fact in the SB queue for the node. This is found by searching the queue, i.e., walking through all the SB blocks in the queue until one is found with a class member list that is identical to the class member list for the current token. This SB block is then dequeued and destroyed. Also, the fact that the test passed indicates that additional tokens were made when the machine A class member was created, and those tokens must be sought out and destroyed since they mention (typically, they point to) a class member that is being destroyed. A new token (a DELETE token) is created for each successor to the current node, and these are all placed on the stack for later processing.
In summary, processing for a DELETE token exactly token. All tests are repeated. When a test is passed, there is an additional expense of searching for the right SB to excise. When a DELETE token arrives at a positive beta-node from one direction, it must be paired with all class member lists from SBs enqueued off the opposite ancestor. For each test that passes, the SB in the current block must be found and excised, and new tokens must be sent to successors. Processing of a DELETE token at a negative beta-node likewise undoes the work of a MAKE token.
The computational expense of processing DELETE tokens is greater than that for processing MAKE tokens. It is frequently necessary to do an additional search of the SB queue at a node to find and excise the appropriate SBs.
RETE Processing as Modified According to the Invention
It was unexpectedly observed that if additional information links were maintained in an SB with its successor SBs, then those SBs that mention the same class member list as in the original SB could immediately be deleted if the original SB were deleted. The process for creating new SBs is largely unchanged, other than the responsibility for saving the additional information. However, in the resulting structure, a class member is the root of a tree of all SBs (and instantiations) that mention the class member, the class member itself being treated like an SB enqueued off an anchor node. Thus, deletion of all SBs (and instantiations) that mention the class member is largely a matter of walking a tree and excising all SBs encountered.
The algorithm can be implemented so that no test is ever repeated. This reduction in the total number of tests to execute RETE processing is especially important when tests are slow lo execute; for example, when class members are stored on a slower storage medium, and accessing class members for testing is computationally expensive. Also, with the invention described herein, no searching of SB queues is required to find the SBs to be excised. This can markedly speed up execution of RETE processing, depending on the length of the SB queues. In this invention, an SB might have the following declaration:
______________________________________Declare improved-satisfaction-block,next-sat-block-in-queue /* used to enqueue this /* block in the doubly-previous-sat-block-in-queue /* linked list of all /* SBs for this nodelist-of-class-members, /* list of members /* passing test of nodeleft-descendant-SB, /* points to any left /* descendant or is /* nullleft-ancestor-SB, /* left ancestor /* pointer, null if no /* lf ancnext-left-sibling-SB, /* doubly-linked list /* of all SBs with theprevious-left-sibling-SB, /* same left ancestorright-descendant-SB, /* points to any right /* descendant, or nullright-ancestor-SB, /* right ancestor pntr, /* null if no rght ancnext-right-sibling-SB, /* doubly-linked list /* of all SBs with theprevious-right-sibling-SB; /* same right ancestor______________________________________
If node N is a successor of node M in a RETE network (i.e., there is an arc from M to N), and if X is an SB queued off M, and Y is an SB queued off N so that the class member list in X is an initial or terminal segment of the list in Y--so that the deletion of X would cause (using classic RETE processing techniques) tokens to be generated that would result in the deletion of Y, then say that Y is an immediate descendant or a successor of X, and say that X is an immediate ancestor or a predecessor of Y.
If M is a left (or right) predecessor of N, then say that X is a left (or right, respectively) predecessor of Y, and Y is a left (or right, respectively) successor of X. If N is a beta-node, there may be many SBs enqueued off N that are all immediate descendants of the same SB enqueued off M. However, a given SB can have at most one left and at most one right immediate ancestor.
Fields similar to those added to the SB declaration in order to arrive at the improved SB declaration (but excluding ancestor pointers) can be associated with each class member. Thus, in all particulars, a class member itself can be treated like an SB insofar as handling creations and deletions. Likewise, fields similar to those in an improved SB (excluding those that point to descendants) can be added to instantiations, as instantiations record what lists of class members pass through production nodes and they are similar to and treated like SBs.
The sibling fields in an improved satisfaction block are used to form a doubly-linked (usually circular) list of all SBs that have a common immediate ancestor. The left and right descendant fields point respectively to any left/right descendant. The left and right ancestor fields are each either set to point to the appropriate ancestor SB if such exists, or are set to a null value if no such ancestor SB exists.
When a MAKE token is being processed at either an alpha or a positive beta-node and a test is passed, all ancestor SBs are known and all the fields in an improved SB can be easily set to the correct values. When a delete of a class member is being processed, a depth-first walk of the descendant SB tree can be executed, and each SB can be deleted from the doubly-linked queue of sibling SBs. If that deletion exhausts the sibling queue, then the predecessor SB's descendant field can be set to null. If the predecessor SB's descendant field points to the deleted SB and the sibling queue is not depleted by the deletion, then the ancestor SB's descendant field can be set to point to another descendant SB. Once an SB is no longer referred to (pointed to) by any other SB, it can safely be destroyed. Care must be taken to eliminate all left and all right descendants of any SB that is going to be deleted.
Processing at negative beta-nodes can be done in several ways. However, it is not possible to simply follow an immediate translation of the above-described techniques into the world of negative beta-nodes. The problem in using the classic approach to processing at negative beta-nodes is that a complete record is not maintained of the result of every test performed at a negative beta-node. With the processing for positive beta-nodes, as described above, every passing test is recorded in an SB. A failing test is recorded by the nonexistence of an SB.
In contrast, the SB queue for a negative beta-node (with the classic algorithm as earlier described) is a subset of the SB queue for the left ancestor node. An SB is created and kept (off the negative beta-node) exactly in those cases where no SB in the right ancestor's queue passes the test when paired with the SB from the left ancestor. Thus, the results of all tests involving SBs that appear in the negative beta-nodes's SB queue are known; namely, all such tests failed. However, if an SB from a left ancestor does not reappear in the negative beta-node's SB queue, then there is no information retained about which SB or SBs from the right ancestor node stopped the left arriving SB by passing the test when the left and right SBs were coupled together.
Since negative beta-nodes tend to be significantly less common than positive beta-nodes, it is possible to treat them using an approach similar to that in the classic RETE processing while still obtaining marked speed improvements for most applications. Using this approach, the elimination of an SB from a node that is a right ancestor of a negative beta-node would trigger the spawning of DELETE tokens that would be passed on to the negative beta-node and processed in the classical way.
It is also possible to keep additional information at each negative beta-node about which SBs from the right stop which SBs arriving from the left. This can be done, for instance, by keeping a list (the standard SB queue for the negative beta-node) of all left arriving SBs that are not stopped, and also by keeping another list of all left arriving SBs that are stopped and keeping with each entry in that list another list of all the right arriving SBs that stop the associated left arriving SBs. Blocks in this new list might be called Stopping SB Blocks, or SSBBs. In this case, fields similar to those in the improved-satisfaction-blocks (outlined above) can be used to link SSBBs to their ancestor SBs. While the details of the algorithm are different for processing at positive and negative beta-nodes, the general approach is similar to that outlined above for the processing done a alpha and positive beta-nodes.
Pseudo-code Implementation and Comment
One use of the RETE algorithm and of the method of this invention is in the implementation of the pattern matching for data-driven production systems. The control cycle for such a system is shown with reference to FIG. 2. In that environment, when a program is first initialized, the RETE network for the set of rules in the application must be built. However, the invention relates to modifications to a RETE network once built, and the following discussion assumes that one has already been compiled.
The fundamental loop or cycle of execution for a data-driven production system is the Match-Resolve-Act cycle. This is illustrated in FIG. 2 and set out in the pseudo-code outline as follows:
______________________________________Some initial conflict set (set of all instantiations)is given;Do Forever;Call conflict-resolution;/* select the best instantiation to fireIf there is a best instantiationThen Do;Fire the best instantiation;/* Note that during the course of firing the/* instantiation, the action code will initiate/* changes to working memory. The application/* code will call MAKE, DELETE, and MODIFY to/* notify the RETE algorithm about changes to/* working memory, and the RETE algorithm will/* push these changes through the RETE network/* in order to compute the resulting changes/* to the conflict set.MAKE, DELETE, and MODIFY may be called by theaction part of a rule during the execution ofthe action part of the rule;End;Else Do; /* the conflict set is emptyReturn to the user of the application and allowhim to terminate execution or to interactivelychange working memory and therein initiate callsto MAKE, DELETE, or MODIFY;End;End;______________________________________
The heart of the RETE processing is thus in the routines MAKE, DELETE, and MODIFY. These routines are notified of changes to working memory, and they push those changes through the RETE network and thereby compute the corresponding changes to the conflict set. An outline of these routines follows.
As derived from the illustrative example in the previous section, the data structures that correspond to the following declarations shall be used:
______________________________________Declare tokenlist-of-class-members, /* list of one or more /* class membersnode, /* identifies node where /* tests will be attempteddirection; /* ancestor that passed the /* token is LEFT or RIGHT /* of the node in the token______________________________________
It should be noted that tokens will only be used for MAKE-type actions in the outlined implementation; thus, there is no change-type field in this declaration of a token.
The declaration of a Satisfaction Block (SB) should be formatted as:
______________________________________Declare improved-satisfaction-block,next-sat-block-in-queue /* used to enqueue this /* block in the doubly-previous-sat-block-in-queue /* linked list of all /* SBs for this nodelist-of-class-members, /* list of members /* passing test of nodeleft-descendant-SB, /* points to any left /* descendant or is /* nullleft-ancestor-SB, /* left ancestor /* pointer, null if no /* lf ancnext-left-sibling-SB, /* doubly-linked list /* of all SBs with theprevious-left-sibling-SB, /* same left ancestorright-descendant-SB, /* points to any right /* descendant, or nullright-ancestor-SB, /* right ancestor pntr, /* null if no rght ancnext-right-sibling-SB, /* doubly-linked list /* of all SBs with theprevious-right-sibling-SB; /* same right ancestor______________________________________
The declaration of a Stopped SB Block (SSBB) consists of:
______________________________________Declare stopped-SB-block,next-SBBB-in-queue, /* used to enqueue this /* block in the doubly-previous-SSBB-in-queue, /* linked list of all /* SSBBs for this nodeleft-ancestor, /* points to stopped SBnext-left-sibling, /* doubly-linked list of /* all SBs and SSBBsprevious-left-sibling, /* with same left ancestorright-ancestor, /* points to stopping SBnext-right-sibling, /* doubly-linked list of /* all SBs and SSBBsprevious-right-sibling; /* with same right ancestor______________________________________
MAKE is passed a pointer to a just created class member and an identifier of the class. It computes the corresponding changes to the conflict set.
______________________________________MAKE(class-member,class-identifier);Locate the anchor for the class specified by theclass-identifier;Enqueue the newly created class member in the classmember queue for the class (the queue is based atthe anchor for the class);Create a token and push it onto the token stackwith class-member as its (length one) list ofclass memberswith the anchor for the class as its RETE nodewith LEFT direction;Call MAKE-PROCESS to do the RETE processing;/* the input to MAKE-PROCESS is the token stackReturn to the caller;End MAKE;______________________________________
DELETE is passed a pointer to the class member that is to be deleted. DELETE computes the corresponding changes to the conflict set. Thereafter, it frees up the storage being used by the class member.
______________________________________DELETE(class-member):Call DELETE-PROCESS(class-member); /* do the RETE /* processingFree class-member's storage block;End DELETE;______________________________________
MODIFY is passed a pointer to the class member that is to be changed. It is also passed a description of the field that is to change, and it is passed the new value that is to be assigned to the field. MODIFY will delete the old copy of the class member insofar as the RETE algorithm is concerned. Then it makes the indicated change to the class member, and does the RETE processing to reflect the creation of a new class member replacing the old one, but with the one field changed.
______________________________________MODIFY(class-member,class-identifier,field-identifier,new-value-for-field):Call DELETE-PROCESS(class-member);Assign new value to field to be changed inclass-member;Call MAKE(class-member,class-identifier);End MODIFY;______________________________________
Thus, it can be seen that the heart of the processing takes place in the two routines MAKE-PROCESS and DELETE-PROCESS. These routines are outlined in pseudo-code. First, consider the MAKE-PROCESS routine. As mentioned before, the input to MAKE-PROCESS is the token stack, and MAKE-PROCESS is driven by the token stack. When that stack is empty, then MAKE-PROCESS's work is complete and it returns to the caller.
______________________________________MAKE-PROCESS:Do while token stack is not empty;Pop the top token off the token stack and call itthis-token;If node of this-token is a class anchor (so tokenlist is a list of one SB and it is a classmember)Then Do;/* use SET-SB-AND-SEND-ON to create SB/* recording passed test and to generate/* tokens for each successor of anchorCall SET-SB-AND-SEND-ON(anchor node, list ofone class member - same as list in this-token, null, null);End;ElseIf node of the token is an alpha-nodeThen Do;Execute the test associated with the node forthe one class member in the class memberlist of this-token;If the test passedThen Do;/* use SET-SB-AND-SEND-ON to create SB/* recording passed test and to generate/* tokens for each successor of anchorCall SET-SB-AND-SEND-ON(node of this-token,class member list of this-token, leftancestor SB, null);End;/* else the test failed, and we do nothing/* more for this-tokenEnd;ElseIf node of the token is a positive beta-nodeThen Do;Do for each SB in the SB queue of theancestor in the opposite direction fromthat of the arriving token;Form an augmented list by concatenating thelist of class members from the SB withthe list of class members from this-token;Execute the test associated with this nodefor the augmented list;If the test passedThen Call SET-SB-AND-SEND-ON(node of this-token, augmented list, left ancestor SB,right ancestor SB);End;End;ElseIf node of the token is a negative beta-nodeThen Do;If token is from leftThen Do;Do for each SB in the SB queue of the rightancestor;Form an augmented list by concatenatingthe list of class members (one classmember in this case) from the SB withthe list of class members from this-token;Execute the test associated with thisnode for the augmented list;If the test passedThen create and enqueue an SSBB pointingto the left and right ancestor SBs;End;If no test passed among tests for all rightancestor's SBsThen Call SET-SB-AND-SEND-ON(node of this-token, list from this-token, leftancestor SB, null);End;Else Do; /* token is from the rightDo for each SB in the SB queue of the leftancestor;Form an augmented list by concatenatingthe list of class members from the SBwith the list of class members (oflength one) from this-token;Execute the test associated with thisnode for the augmented list;If the test passedThen Do;Create and enqueue an SSBB pointing tothe left and right ancestor SBs;If there exist no other SSBBs enqueuedoff this node that refer to the sameleft ancestor SBThen Do;Locate the SB in the queue off thisnode that has the same class memberlist as the SB from the leftancestor node;Call DELETE-PROCESS(pointer to the SBenqueued off this node - as locatedabove);End;End;End;End;End;ElseIf node of the token is a positive merge-nodeThen Do;Do for each SB in the SB queue of theancestor in the opposite direction fromthat of the arriving token;Form an augmented list by concatenating thelist of class members from the SB withthe list of class members from this-token;Call SET-SB-AND-SEND-ON(node of this-token,augmented list, left ancestor SB, rightancestor SB);End;End;ElseIf node of the token is a negative merge-nodeThen Do;If token is from leftThen Do;Do for each SB in the SB queue of the rightancestor;Create and enqueue an SSBB pointing tothe left and right ancestor SBs;End;If the right ancestor node's SB queue isemptyThen Call SET-SB-AND-SEND-ON(node of this-token, list from this-token, leftancestor SB, null);End;Else Do; /* token is from the rightDo for each SB in the SB queue of the leftancestor;Create and enqueue an SSBB pointing tothe left and right ancestor SBs;If there exist no other SSBBs enqueuedoff this node that refer to the sameleft ancestor SBThen Do;Locate the SB in the queue off thisnode that has the same class memberlist as the SB from the left ancestornode;Call DELETE-PROCESS(pointer to the SBenqueued off this node - as locatedabove);End;End;End;End;Else /* the node type must be a production node -/* all other possibilities have been/* exhaustedDo;Create a new instantiation made up of list ofclass members from the token and the ruleassociated with the node in the token;End;End of do while loop;Return to callerEnd MAKE-PROCESS;______________________________________
There are several references in the above to the utility routine SET-SB-AND-SEND-ON. This routine accepts a node, a list of pointers to class members, a pointer to a left ancestor (possibly null), and a pointer to a right ancestor (possibly null). It does two things. First, it creates an SB from the list of pointers to class members, and it enqueues that SB off the passed node. Second, it loops through each successor node in the RETE network of the passed node, and for each it creates and pushes a token. A pseudo-code description follows:
______________________________________SET-SB-AND-SEND-ON(parent-node,list-of-class-members,left-ancestor-SB,right-ancestor-SB):Create an SB with list-of-class-members and enqueueit off parent-node;Do for each RETE node successor of parent-node;Make a tokenwith node being the successorwith direction being the kind (left or right)of ancestor that the parent-node is to thesuccessorwith the list of class members beinglist-of-class-members;Push the token on the token stack;End;End SET-SB-AND-SEND-ON;______________________________________
It remains to outline the DELETE-PROCESS routine. This is called to delete all references in the RETE network to an SB, an SSBB, in instantiation, or a class member--which, for the purposes of the RETE algorithm, is a special kind of SB. DELETE-PROCESS is called and passed either a pointer to a class member or a pointer to an SB. If a class member is passed, then that class member is deleted from its class queue. If an SB is passed, then that SB is deleted from the SB queue in which it resided--while the integrity of all SB queues is maintained. Whether as SB or a class member is passed, DELETE-PROCESS proceeds to call itself recursively in order to eliminate all left and right descendant SBs.
Thinking of all the descendants of an SB as forming a tree, the recursive invocation of DELETE-PROCESS actually walks that tree in a depth-first manner and just before leaving a node in that tree (which is an SB), that SB is excised from all queues in which it resides and the SB is destroyed (i.e., the block of storage is freed):
______________________________________DELETE-PROCESS(SB-to-delete):/* recursively invoked where SB-to-delete is either/* an SB or a class member to be deletedIf SB-to-delete has a left successor SBThen Call DELETE-PROCESS(that left successor SB);If SB-to-delete has a right successor SBThen Call DELETE-PROCESS(that right successor SB);Excise SB-to-delete from the doubly-linked queue ofall SBs off the node with which SB-to-delete isassociated;If SB-to-delete has a left sibling SBThen Do;If SB-to-delete has a left ancestorand if the left successor field of the leftancestor points to SB-to-deleteThen reset that left successor field to point toa sibling of SB-to-delete;Excise SB-to-delete from its doubly-linked queueof left siblings;Call DELETE-PROCESS(left sibling ofSB-to-delete);End;Else /* SB-to-delete is alone in the left sibling/*queueIf SB-to-delete has a left ancestorThen set the left successor field of that leftancestor to null;If SB-to-delete is an SSBB(and it is known that SB-to-delete has a leftancestor)and there are no other SSBBs enqueued atSB-to-delete's node that are left siblings ofSB-to-delete (i.e., same left anc)Then Do;Call SET-SB-AND-SEND-ON(current node, classmember list of SB-to-delete's left ancestor,SB-to-delete's left ancestor, SB-to-delete'sright ancestor);Call MAKE-PROCESS;End;If SB-to-delete has a right sibling SBThen Do;If SB-to-delete has a right ancestorand if the right successor field of the rightancestor points to SB-to-deleteThen reset that right successor field to pointto a sibling of SB-to-delete;Excise SB-to-delete from its doubly-linked queueof right siblings;Call DELETE-PROCESS(right sibling ofSB-to-delete);End;Else /* SB-to-delete is alone in the right sibling/* queueIf SB-to-delete has a right ancestorThen set the right successor field of that rightancestor to null;If SB-to-delete is an SB rather than a class memberThen free SB-to-delete's storage block (and sodestroy SB-to-delete);Return to caller;End DELETE-PROCESS;______________________________________
It will be further understood by those skilled in this art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.
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A demand-driven AI production system utilizing a RETE network for comparison matching in a condition/data match, rule-selection, and rule-firing execution cycle in which the RETE network is modified to maintain a list of instantiations satisfying the match conditions expressed in each node of the RETE network, passing of tokens to descendant nodes upon a comparison match, maintaining patterns to all ancestor nodes through which the tokens have passed, and traversing the patterns as a path for avoiding those RETE pattern matchings redundant between a previous match and a current match in progress.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 60/970,973 filed 9 Sep. 2007. The disclosure of this application is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to deuterium-enriched paclitaxel, pharmaceutical compositions containing the same, and methods of using the same.
BACKGROUND OF THE INVENTION
[0003] Paclitaxel, shown below, is a well known taxoid antineoplastic agent.
[0000]
[0000] Since paclitaxel is a known and useful pharmaceutical, it is desirable to discover novel derivatives thereof. Paclitaxel is described in U.S. Pat. Nos. 4,857,653, 5,015,744, and 5,200,534; the contents of which are incorporated herein by reference.
SUMMARY OF THE INVENTION
[0004] Accordingly, one object of the present invention is to provide deuterium-enriched paclitaxel or a pharmaceutically acceptable salt thereof.
[0005] It is another object of the present invention to provide pharmaceutical compositions comprising a pharmaceutically acceptable carrier and a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0006] It is another object of the present invention to provide a method for treating a disease selected from Kaposi's sarcoma and/or cancer of the lung, ovarian, and breast, comprising administering to a host in need of such treatment a therapeutically effective amount of at least one of the deuterium-enriched compounds of the present invention or a pharmaceutically acceptable salt thereof.
[0007] It is another object of the present invention to provide a novel deuterium-enriched paclitaxel or a pharmaceutically acceptable salt thereof for use in therapy.
[0008] It is another object of the present invention to provide the use of a novel deuterium-enriched paclitaxel or a pharmaceutically acceptable salt thereof for the manufacture of a medicament (e.g., for the treatment of Kaposi's sarcoma and/or cancer of the lung, ovarian, and breast).
[0009] These and other objects, which will become apparent during the following detailed description, have been achieved by the inventor's discovery of the presently claimed deuterium-enriched paclitaxel.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0010] Deuterium (D or 2 H) is a stable, non-radioactive isotope of hydrogen and has an atomic weight of 2.0144. Hydrogen naturally occurs as a mixture of the isotopes 1 H (hydrogen or protium), D ( 2 H or deuterium), and T ( 3 H or tritium). The natural abundance of deuterium is 0.015%. One of ordinary skill in the art recognizes that in all chemical compounds with a H atom, the H atom actually represents a mixture of H and D, with about 0.015% being D. Thus, compounds with a level of deuterium that has been enriched to be greater than its natural abundance of 0.015%, should be considered unnatural and, as a result, novel over their non-enriched counterparts.
[0011] All percentages given for the amount of deuterium present are mole percentages.
[0012] It can be quite difficult in the laboratory to achieve 100% deuteration at any one site of a lab scale amount of compound (e.g., milligram or greater). When 100% deuteration is recited or a deuterium atom is specifically shown in a structure, it is assumed that a small percentage of hydrogen may still be present. Deuterium-enriched can be achieved by either exchanging protons with deuterium or by synthesizing the molecule with enriched starting materials.
[0013] The present invention provides deuterium-enriched paclitaxel or a pharmaceutically acceptable salt thereof. There are fifty-one hydrogen atoms in the paclitaxel portion of paclitaxel as show by variables R 1 -R 51 in formula I below.
[0000]
[0014] The hydrogens present on paclitaxel have different capacities for exchange with deuterium. Hydrogen atoms R 1 -R 4 are easily exchangeable under physiological conditions and, if replaced by deuterium atoms, it is expected that they will readily exchange for protons after administration to a patient. The remaining hydrogen atoms are not easily exchangeable for deuterium atoms. However, deuterium atoms at the remaining positions may be incorporated by the use of deuterated starting materials or intermediates during the construction of paclitaxel.
[0015] The present invention is based on increasing the amount of deuterium present in paclitaxel above its natural abundance. This increasing is called enrichment or deuterium-enrichment. If not specifically noted, the percentage of enrichment refers to the percentage of deuterium present in the compound, mixture of compounds, or composition. Examples of the amount of enrichment include from about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16, 21, 25, 29, 33, 37, 42, 46, 50, 54, 58, 63, 67, 71, 75, 79, 84, 88, 92, 96, to about 100 mol %. Since there are 51 hydrogens in paclitaxel, replacement of a single hydrogen atom with deuterium would result in a molecule with about 2% deuterium enrichment. In order to achieve enrichment less than about 2%, but above the natural abundance, only partial deuteration of one site is required. Thus, less than about 2% enrichment would still refer to deuterium-enriched paclitaxel.
[0016] With the natural abundance of deuterium being 0.015%, one would expect that for approximately every 6,667 molecules of paclitaxel (1/0.00015=6,667), there is one naturally occurring molecule with one deuterium present. Since paclitaxel has 51 positions, one would roughly expect that for approximately every 340,017 molecules of paclitaxel (51×6,667), all 51 different, naturally occurring, mono-deuterated paclitaxels would be present. This approximation is a rough estimate as it doesn't take into account the different exchange rates of the hydrogen atoms on paclitaxel. For naturally occurring molecules with more than one deuterium, the numbers become vastly larger. In view of this natural abundance, the present invention, in an embodiment, relates to an amount of an deuterium enriched compound, whereby the enrichment recited will be more than naturally occurring deuterated molecules.
[0017] In view of the natural abundance of deuterium-enriched paclitaxel, the present invention also relates to isolated or purified deuterium-enriched paclitaxel. The isolated or purified deuterium-enriched paclitaxel is a group of molecules whose deuterium levels are above the naturally occurring levels (e.g., 2%). The isolated or purified deuterium-enriched paclitaxel can be obtained by techniques known to those of skill in the art (e.g., see the syntheses described below).
[0018] The present invention also relates to compositions comprising deuterium-enriched paclitaxel. The compositions require the presence of deuterium-enriched paclitaxel which is greater than its natural abundance. For example, the compositions of the present invention can comprise (a) a pg of a deuterium-enriched paclitaxel; (b) a mg of a deuterium-enriched paclitaxel; and, (c) a gram of a deuterium-enriched paclitaxel.
[0019] In an embodiment, the present invention provides an amount of a novel deuterium-enriched paclitaxel.
[0020] Examples of amounts include, but are not limited to (a) at least 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, to 1 mole, (b) at least 0.1 moles, and (c) at least 1 mole of the compound. The present amounts also cover lab-scale (e.g., gram scale), kilo-lab scale (e.g., kilogram scale), and industrial or commercial scale (e.g., multi-kilogram or above scale) quantities as these will be more useful in the actual manufacture of a pharmaceutical. Industrial/commercial scale refers to the amount of product that would be produced in a batch that was designed for clinical testing, formulation, sale/distribution to the public, etc.
[0021] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0022] wherein R 1 -R 51 are independently selected from H and D; and the abundance of deuterium in R 1 -R 51 is at least 2%. The abundance can also be (a) at least 4%, (b) at least 10%, (c) at least 16%, (d) at least 22%, (e) at least 27%, (f) at least 33%, (g) at least 39%, (h) at least 45%, (i) at least 51%, (j) at least 57%, (k) at least 63%, (l) at least 69%, (m) at least 75%, (n) at least 80%, (o) at least 86%, (p) at least 92%, (q) at least 98%, and (r) 100%.
[0023] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 4 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0024] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 5 -R 9 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0025] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 10 and R 16 is at least 50%. The abundance can also be (a) 100%.
[0026] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 11 -R 15 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0027] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 22 -R 24 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0028] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 34 -R 36 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0029] In another embodiment, the present invention provides a novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 39 -R 43 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0030] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0031] wherein R 1 -R 51 are independently selected from H and D; and the abundance of deuterium in R 1 -R 51 is at least 2%. The abundance can also be (a) at least 4%, (b) at least 10%, (c) at least 16%, (d) at least 22%, (e) at least 27%, (f) at least 33%, (g) at least 39%, (h) at least 45%, (i) at least 51%, (j) at least 57%, (k) at least 63%, (l) at least 69%, (m) at least 75%, (n) at least 80%, (o) at least 86%, (p) at least 92%, (q) at least 98%, and (r) 100%.
[0032] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 4 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0033] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 5 -R 9 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0034] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 10 and R 16 is at least 50%. The abundance can also be (a) 100%.
[0035] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 11 -R 15 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0036] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 22 -R 24 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0037] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 34 -R 36 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0038] In another embodiment, the present invention provides an isolated novel, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 39 -R 43 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0039] In another embodiment, the present invention provides novel mixture of deuterium enriched compounds of formula I or a pharmaceutically acceptable salt thereof.
[0000]
[0040] wherein R 1 -R 51 are independently selected from H and D; and the abundance of deuterium in R 1 -R 51 is at least 2%. The abundance can also be (a) at least 4%, (b) at least 10%, (c) at least 16%, (d) at least 22%, (e) at least 27%, (f) at least 33%, (g) at least 39%, (h) at least 45%, (i) at least 51%, (j) at least 57%, (k) at least 63%, (l) at least 69%, (m) at least 75%, (n) at least 80%, (o) at least 86%, (p) at least 92%, (q) at least 98%, and (r) 100%.
[0041] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 1 -R 4 is at least 25%. The abundance can also be (a) at least 50%, (b) at least 75%, and (c) 100%.
[0042] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 5 -R 9 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0043] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 10 and R 16 is at least 50%. The abundance can also be (a) 100%.
[0044] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 11 -R 15 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0045] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 22 -R 24 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0046] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 34 -R 36 is at least 33%. The abundance can also be (a) at least 67%, and (b) 100%.
[0047] In another embodiment, the present invention provides a novel mixture of, deuterium enriched compound of formula I or a pharmaceutically acceptable salt thereof, wherein the abundance of deuterium in R 39 -R 43 is at least 20%. The abundance can also be (a) at least 40%, (b) at least 60%, (c) at least 80%, and (d) 100%.
[0048] In another embodiment, the present invention provides novel pharmaceutical compositions, comprising: a pharmaceutically acceptable carrier and a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0049] In another embodiment, the present invention provides a novel method for treating Kaposi's sarcoma and/or cancer of the lung, ovarian, and breast comprising: administering to a patient in need thereof a therapeutically effective amount of a deuterium-enriched compound of the present invention.
[0050] In another embodiment, the present invention provides an amount of a deuterium-enriched compound of the present invention as described above for use in therapy.
[0051] In another embodiment, the present invention provides the use of an amount of a deuterium-enriched compound of the present invention for the manufacture of a medicament (e.g., for the treatment of Kaposi's sarcoma and/or cancer of the lung, ovarian, and breast).
[0052] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. This invention encompasses all combinations of preferred aspects of the invention noted herein. It is understood that any and all embodiments of the present invention may be taken in conjunction with any other embodiment or embodiments to describe additional more preferred embodiments. It is also to be understood that each individual element of the preferred embodiments is intended to be taken individually as its own independent preferred embodiment. Furthermore, any element of an embodiment is meant to be combined with any and all other elements from any embodiment to describe an additional embodiment.
DEFINITIONS
[0053] The examples provided in the definitions present in this application are non-inclusive unless otherwise stated. They include but are not limited to the recited examples.
[0054] The compounds of the present invention may have asymmetric centers. Compounds of the present invention containing an asymmetrically substituted atom may be isolated in optically active or racemic forms. It is well known in the art how to prepare optically active forms, such as by resolution of racemic forms or by synthesis from optically active starting materials. All processes used to prepare compounds of the present invention and intermediates made therein are considered to be part of the present invention. All tautomers of shown or described compounds are also considered to be part of the present invention.
[0055] “Host” preferably refers to a human. It also includes other mammals including the equine, porcine, bovine, feline, and canine families.
[0056] “Treating” or “treatment” covers the treatment of a disease-state in a mammal, and includes: (a) preventing the disease-state from occurring in a mammal, in particular, when such mammal is predisposed to the disease-state but has not yet been diagnosed as having it; (b) inhibiting the disease-state, e.g., arresting it development; and/or (c) relieving the disease-state, e.g., causing regression of the disease state until a desired endpoint is reached. Treating also includes the amelioration of a symptom of a disease (e.g., lessen the pain or discomfort), wherein such amelioration may or may not be directly affecting the disease (e.g., cause, transmission, expression, etc.).
[0057] “Therapeutically effective amount” includes an amount of a compound of the present invention that is effective when administered alone or in combination to treat the desired condition or disorder. “Therapeutically effective amount” includes an amount of the combination of compounds claimed that is effective to treat the desired condition or disorder. The combination of compounds is preferably a synergistic combination. Synergy, as described, for example, by Chou and Talalay, Adv. Enzyme Regul. 1984, 22:27-55, occurs when the effect of the compounds when administered in combination is greater than the additive effect of the compounds when administered alone as a single agent. In general, a synergistic effect is most clearly demonstrated at sub-optimal concentrations of the compounds. Synergy can be in terms of lower cytotoxicity, increased antiviral effect, or some other beneficial effect of the combination compared with the individual components.
[0058] “Pharmaceutically acceptable salts” refer to derivatives of the disclosed compounds wherein the parent compound is modified by making acid or base salts thereof. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of the basic residues. The pharmaceutically acceptable salts include the conventional quaternary ammonium salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include, but are not limited to, those derived from inorganic and organic acids selected from 1,2-ethanedisulfonic, 2-acetoxybenzoic, 2-hydroxyethanesulfonic, acetic, ascorbic, benzenesulfonic, benzoic, bicarbonic, carbonic, citric, edetic, ethane disulfonic, ethane sulfonic, fumaric, glucoheptonic, gluconic, glutamic, glycolic, glycollyarsanilic, hexylresorcinic, hydrabamic, hydrobromic, hydrochloric, hydroiodide, hydroxymaleic, hydroxynaphthoic, isethionic, lactic, lactobionic, lauryl sulfonic, maleic, malic, mandelic, methanesulfonic, napsylic, nitric, oxalic, pamoic, pantothenic, phenylacetic, phosphoric, polygalacturonic, propionic, salicyclic, stearic, subacetic, succinic, sulfamic, sulfanilic, sulfuric, tannic, tartaric, and toluenesulfonic.
EXAMPLES
[0059] Table 1 provides compounds that are representative examples of the present invention. When one of R 1 -R 51 is present, it is selected from H or D.
[0000]
1
2
3
4
5
6
7
8
[0060] Table 2 provides compounds that are representative examples of the present invention. Where H is shown, it represents naturally abundant hydrogen.
[0000]
9
10
11
12
13
14
15
16
[0061] 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 that as specifically described herein.
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The present application describes deuterium-enriched paclitaxel, pharmaceutically acceptable salt forms thereof, and methods of treating using the same.
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CROSS REFERENCES TO RELATED APPLICATIONS
Not applicable.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
The present invention relates to calenders in general, and to supercalenders in particular.
A calender, particularly a supercalender, can increase the value of the paper manufactured on a papermaking machine without increasing the cost of fiber, and with only a small increase in energy cost. By improving the surface finish or other attributes of the paper web, the value of the paper is increased without otherwise modifying the papermaking machinery or process. Because of the large fixed costs and high production rates typically involved in paper manufacture, increasing the value of the paper produced can be a particularly advantageous way to increase revenue produced by a papermaking machine.
A supercalender is comprised of a stack of rolls, sometimes as many as ten, eleven, or more, which form a plurality of nips through which the paper web is directed. Pressure and often heat are applied to the web as it passes through the nips of the supercalender. A supercalender can impart an improved, or more valuable surface finish, can correct curl, and can improve paper caliper variations.
Improving the supercalender has involved controlling the nip force between adjacent rolls by supporting each roll independently of the other rolls in the stack of rolls; the use of crown control rolls, and the use of higher roll temperatures. The use of higher roll temperatures requires an ability to rapidly open a calender stack so that the high-temperature rolls do not overheat opposed compliant rolls when a paper break occurs.
Where a plurality of intermediate rolls are mounted between a fixedly mounted, variable-crown upper roll and a movable variable-crown lower roll, one known technique for controlling inter roll nip loading is to mount the intermediate roll bearings on pivot arms. The pivot arms can be supported by support cylinders as disclosed in U.S. Pat. No. 4,901,637 to Hagel et al.; U.S. Pat. No. 5,438,920 to Koivukunnas et al.; U.S. Pat. No. 5,806,415 to Lipponen et al.; and U.S. application Ser. No. 09/303,587 (PCT/FI98/00392), filed May 7, 1998, claiming priority from U.S. provisional application 60/045,871 to Maenpaa et al., which are each incorporated herein by reference. The support cylinders allow control of the nip loading between each of the supercalender rolls.
A supercalender may employ rolls of varying diameters and of different types. One type of roll has a polymer roll cover. The resilient roll cover provides a wider nip due to compression of the roll at the nip between rolls. Polymer covered rolls have a relatively long life and require only relatively small reductions in diameter due to refinishing the roll surface during the life of the roll. Smooth metal rolls provide a hard smooth surface against which the paper is compressed. Although metal rolls may be refinished, relatively little material is removed over time. Metal rolls may be heated, typically by hot water, steam or induction heating. Another type of known roll is a filled roll which is comprised of a large number of disks of a material like cotton, flax, or paper. Each disk has a central hole and thousands of individual disks or sheets are stacked up on a metal core and compressed axially at very high pressures. The resulting roll is finished by turning the surface of the roll formed by the compressed disks of fabric or paper. The surface of a filled roll has a relatively short service life requiring frequent machining so that a filled roll decreases substantially in diameter over the life of the roll.
Many existing calenders are of the closed frame, or A-frame type, which means the roll bearings at the ends of the individual calender rolls making up the supercalender are held between pairs of vertical frames, which are joined at the top. In these existing calenders, the rolls have bearings which slide on rails between the vertical frames. Nip loading between rolls making up the calender can be controlled only by loading the uppermost roll, which means each successively lower nip has an increased nip loading as the weight of each successive roll adds to the total nip load.
A conventional closed calender cannot rapidly open the nips. Rapid nip opening protects polymer and fiber rolls from damage caused by wads of paper passing through the calender nips. Typically photoeye and web tension sensors detect a paper break and instigate rapid nip opening so that wads of paper formed during a break can pass between calender rolls without damaging them. Existing solutions to rebuilding calenders do allow support of individual rolls by hydraulic pistons which extend between a support frame and the roll bearings. Existing systems, however, do not provide sufficient vertical movement of the roll bearings to accommodate a variety of roll diameters, particularly the ability to accommodate the diameter change of filled rolls over time.
A calender or calender rebuild design is needed which can accommodate a wide variety of calender rolls, and facilitate the use of filled rolls by accommodating the substantial change in roll diameter overtime.
SUMMARY OF THE INVENTION
The calender of this invention may be based on an existing calender of the closed A-frame type. One half of each A-frame in the machine direction is removed and a weldment is bolted to the track of each remaining frame along which the bearing housings of the calender rolls formally rode. Each weldment rests on the calender foundation and consists of two parallel plates which extend in the machine direction 72 inches away from the remaining frames. The lower portion of each weldment has a vertical rail along which the bearing housings of a bottom roll rides. The bottom roll mounted to the bottom bearing is supported by a bottom cylinder which controls the bottom roll's vertical movement and the opening and closing of the calender roll stack.
A top calender roll is fixedly mounted between the weldments. A plurality of intermediate calender rolls are mounted by pivot arms to the weldments, so that each intermediate calender roll is supported on each end by two pivoting arms. Each arm has two plates which extend between the roll end bearing, and extend along either side of the weldment to bearing pins located adjacent to the upstream side of the weldment where the weldment is bolted to the track of the existing frames.
The bearing housings of each roll connect the two plates of each arm to form a single integrated pivot arm. The bearing housings incorporate a stop so that each bearing housing on each pair of pivot arms, when pivoting downwardly comes to rest on resilient pads mounted to weldment stops which extend like teeth from the sides of the weldments. The weldment is substantially open ended, opposite the calender rolls.
Positioned within the sides of the weldments are pairs of load supporting cylinders which extend between cylinder brackets which span the sides of the weldments and piston mounting brackets which extend from the calender roll bearing housings. The piston mounting brackets are narrower than the weldment and fit within the sides of the weldment and between the weldment stops on which rubber pads are mounted, thus accommodating the stroke of the load supporting cylinders without interference of the supporting weldment.
The greater length of the pivot arms combined with the greater stroke of the load support cylinders allows the supercalender to accommodate filled rolls which change diameter substantially over their life, as the surface of the rolls is repeatedly turned down to refurbish the roll surface.
It is an object of the present invention to provide a supercalender which can accommodate calender rolls of varying diameter.
It is another object of the present invention to provide a supercalender in which greater vertical motion of individual calender rolls is provided for.
It is a further object of the present invention to provide a supercalender which can control the nip load on intermediate calender rolls.
It is a still further object of the present invention to provide a supercalender in which intermediate rolls are mounted on pivot arms which minimize lateral displacement of the rolls when they are pivoted on the arms.
Further objects, features and advantages of the invention will be apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of the supercalender rebuild of this invention in the closed position.
FIG. 2 is a side elevational view of the supercalender rebuild of this invention shown in the open position.
FIG. 3 is a broken away side elevational view of the supercalender rebuild of FIG. 1 .
FIG. 4 is an exploded isometric view of the supercalender rebuild of FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring more particularly to FIGS. 1-4, wherein like numbers refer to similar parts, a calender 20 is shown in FIGS. 1 and 2. The calender 20 has two spaced apart frames 24 to which weldments 38 are bolted. A top roll 28 is mounted on the weldment 38 for rotation. A bottom roll 26 is mounted for vertical motion on hydraulic pistons 72 and is slidably mounted to the weldment 38 . A plurality of intermediate rolls 34 are placed one above another, so that when the top roll 28 , bottom roll 26 and intermediate rolls 34 are brought together they form calender nips 29 therebetween.
The calender 20 may be constructed as a rebuild where the rolls 26 , 28 , 34 of an existing calender, and portions of the frame 24 of an existing calender are used in the construction of a new calender 20 . Because of the considerable cost of the calender rolls generally, and particularly of the bottom roll 26 and the top roll 28 which will normally be variable-crown rolls, reuse of the calender rolls will save considerable cost. Reuse of the part of the frame 24 saves the cost and time of constructing a new frame and foundation.
In a supercalender, where a plurality of intermediate calender rolls are positioned between a lower variable-crown roll and a upper variable crown roll, the nip loading uniformity could be controlled by the variable-crown rolls, except for the fact that the rolls extended beyond the paper engaging nip, and relatively heavy roll bearings are cantilevered off the ends of the rolls. In addition, in a conventional supercalender each successive nip must have a higher linear nip load because each roll must support the weight of all the rolls position above it.
The weight of the bearings and the unsupported portions of the rolls cause a downward deflection of the roll ends. Mounting the roll bearings to arms which are supported by hydraulic loading cylinders allows the weight of the unsupported portion of the rolls plus the bearing housings to be supported. As explained more fully in U.S. patent application Ser. No. 09/303,587 (PCT/FI98/00392), the loading angle which defines the linear loading of intermediate rolls can also be controlled by the use of hydraulic loading cylinders which are mounted to support the arms to which the roll bearings are mounted.
Referring to FIGS. 1 and 2, the calender 20 provides the benefit of using hydraulic loading cylinders 30 to support the bearing housings 32 of the intermediate rolls 34 which are mounted on the arms 36 . The roll support arms 36 are mounted to a weldment 38 by pivots 39 . The weldment 38 is bolted to an existing calender frame 24 , as shown in FIG. 4 . The loading cylinders 30 are arranged so that the extension of the pistons 46 do not interfere with the mounting of the loading cylinder 30 of the next higher intermediate roll 34 , as shown in FIG. 1 . The bearing housings 32 of each intermediate roll have piston mounting brackets 42 which extend towards and partly between the sides 44 of the weldment 38 , as shown in FIGS. 3 and 4. Hydraulic loading cylinders 30 is comprised of the piston 46 which is mounted to the piston mounting bracket 42 and a hydraulic cylinder 48 which is mounted between lower support cylinder brackets 50 which are mounted between the two spaced apart vertical walls 44 of the weldment 38 .
The lower support cylinder brackets 50 are mounted below the piston mounting brackets 42 and spaced inwardly towards the pivots 39 which mount the arms 36 . The position and arrangement of the hydraulic loading cylinders 30 , and the way in which they are substantially contained within the weldment 38 allows greater extension of the hydraulic loading cylinder pistons 46 , without the interference between cylinders inherent in the prior art. The greater extension of the hydraulic loading cylinder pistons 46 allows greater vertical movement of the intermediate rolls 34 . Greater movement of the intermediate rolls 34 allows the supercalender to accommodate fiber rolls which decrease in diameter substantially over their useful life. Greater vertical movement also facilitates substituting different intermediate rolls as may be required by a particular grade of paper.
Referring to FIGS. 2 and 3, a rebuilt calender 20 is constructed by tearing down an existing closed calender A-frame (not shown) to leave a single frame 24 consisting of the up machine direction portion of the A-frame of the pre-existing calender, on both the front frame 24 and back (not shown) of the pre-existing calender. The front frame 24 has a track 54 along which previously the bearing housings of the intermediate rolls rode. The weldment 38 has a protruding land 56 which fits within the sides 58 of the track 54 . Bolts 60 mount the weldment 38 to the track 54 of the front frame 24 . The weldment 38 extends over the foundation previously occupied by the portion of the A-frame which was removed.
The weldment has a back 62 and two sides 44 and downstream edges 64 which are thicker than the sides 44 and support one pair of triangular teeth 66 for each intermediate roll 34 . The triangular teeth 66 have upwardly facing surfaces 67 on which are mounted resilient pads 70 and which form stops, which support the intermediate rolls 34 , when the calender 20 is in the open position, as shown in FIG. 2 . Corresponding teeth 68 are formed on the bearing housings 32 of the intermediate rolls 34 . As shown in FIG. 2, when the calender 20 stack is opened by moving the bottom roll 26 down by means of the bottom roll support cylinder 72 , the intermediate rolls 34 come to rest on the upwardly facing surfaces 67 and resilient pads 70 of the triangular teeth 66 which engage the bearing housing teeth 68 . As shown in FIG. 3, the bearing housing of the bottom roll 26 slides along a track 74 formed on lower portions 76 of the weldment 38 .
A gap 78 is formed between the downstream edges 64 , of the weldment 38 . The gap opens into the interior 80 of the weldment 38 . In contradistinction to the prior art, where the hydraulic load cylinders are mounted substantially along the downstream edges of the calender support, the hydraulic loading cylinders 30 of the calender 20 are mounted substantially within the interior 80 of the weldment 38 . The downstream edges 64 of the weldment sides 44 may be tied together for increased stiffness by short bars 81 which extend between the weldment sides 44 . The short bars 81 are positioned to avoid interference with the hydraulic load cylinders 30 . Assembly of the calender 20 is facilitated by access openings 82 which facilitate positioning pairs of opposed bracket parts which form the lower support cylinder brackets 50 which are mounted to the sides 44 of the weldment with bolts 86 .
The access openings 82 also facilitate positioning the lower portions 88 of the hydraulic cylinders 48 within the grooves 90 in the bracket parts 50 . The bracket parts 50 may also be joined by through bolts (not shown) which tie the weldment sides 44 together. In addition, the lower portions 88 of the hydraulic cylinders 48 may be held within the brackets by keys 93 which prevent the hydraulic cylinders 48 from being inadvertently lifted out of the grooves 90 . The pivotal arms 36 are mounted over the pivots 39 which extend outwardly of the weldment sides 44 , closely spaced from the back 62 of the weldment 38 . Pivot brackets 92 overlie the arms 36 and the pivots 39 to provide stronger support to the pivots 39 . The pivot arms 36 are bolted by bolts 94 to ductile cast iron bearing housings 32 , on which the piston mounting brackets 42 are integrally formed.
During assembly, the bearing housings 32 with attached hydraulic load cylinders 30 are bolted to the pivot arms 36 . The bottom of the roll support cylinder 72 may then be positioned the lower portions 88 through access openings 82 so the lower portions 88 ride with in the grooves 90 of the bracket parts 50 . The intermediate rolls 34 , as shown in FIG. 3, are mounted by bearings 102 within the bearing housings 32 . Referring to FIGS. 1 and 2, an inside flyroll 104 is mounted to the inside part 99 of the pivot arm 36 . Alternatively, an outboard flyroll 100 is mounted to a bracket on the bearing housing 32 .
The top roll 28 is fixedly mounted, as shown in FIGS. 1 and 2, to the weldment 38 . All loading of the calender stack is performed by the bottom roll 26 which, as previously described, slides along the track 74 formed on lower portions 76 of the weldment 38 . The calender stack can be rapidly opened, as shown in FIG. 2, by moving the bottom roll 26 downwardly and allowing the pivot arm 36 to come to rest on the upwardly facing surfaces 67 of the teeth 66 . In the open position, gaps of at least about 0.19 inches are formed between each intermediate roll and the preceding roll.
In combination with a greater stroke of the hydraulic loading cylinders 30 , the pivot arms will have a correspondingly greater swing radius between the axis 106 of the intermediate the rolls 34 , and a pivot axis defined by the pivots 39 . Pivoting the arms 36 results in not only vertical movement of the intermediate rolls, but a small horizontal or machine direction motion so that the individual intermediate rolls may not be positioned precisely above, or precisely below another intermediate roll 34 or the top roll 28 or bottom roll 26 . To the extent any intermediate roll 34 forms a nip which is offset from a calender plane 107 extending between the axis 108 of the top roll 28 and the axis 110 of the bottom roll 26 , lateral forces will be developed in the pivot pins 39 . The lateral forces are related to the amount of lateral offset of the intermediate roll 34 axis 106 . These lateral offsets are minimized by positioning the pivot pins 39 and the stops formed by the upwardly facing surfaces 67 to position each intermediate roll so that the intermediate roll axes 106 are initially positioned to the right as viewed in FIGS. 1 and 2 of the calender plane 107 extending between the axes 108 , 110 of the top and bottom rolls. The pivot arms 36 are arranged so that the intermediate roll axes 106 cross the plane 107 twice, thus reducing the total angular displacement of the intermediate roll axes 106 , away from the calender plane 107 , by a factor of four, and the lateral displacement by more than a factor of ten.
The calender 20 achieves an ability to accommodate greater vertical movement in a calender where the rolls are mounted to pivot arms, by using the arms which in proportion to the diameter of the intermediate rolls, are substantially longer, so that intermediate roll diameter is about 40 percent or less of the pivot radius defined between the intermediate roll axis 106 , and the pivots 39 , and by placing the hydraulic loading cylinders 30 in the overlapping diagonal arrangement as shown in FIGS. 1 and 2 so that greater extension of the hydraulic loading cylinders 30 is possible without interference between cylinders. In the prior art, hydraulic loading cylinders are positioned substantially in a vertical line, and thus each loading cylinder could only extend until it came into interference with the loading cylinder immediately above.
The calender 20 , as shown in FIGS. 1 and 2, has a top roll diameter which begins life with a diameter of 34.28 inches, and a bottom roll which begins life with a diameter of 42 inches. The intermediate rolls, depending on roll type, vary between 32 inches for filled rolls, 28.8 in. for polymer rolls, and 24.7 inches for thermal rolls. The rolls will decrease in diameter, in a manner known in the art, due to periodic resurfacing by a turning down of the roll diameters, with the amount of roll diameter reduction being dependent on the roll type. FIG. 2 shows the calender 20 in the open position with maximum diameter rolls, and the rolls resting on stops formed by the surfaces 67 of the triangular teeth 66 . FIG. 1 shows the calender 20 in a closed position with minimum diameter rolls. The total vertical motion of the bottom roll axes is thirty inches between FIG. 1 and FIG. 2 . The pivot radius defined between the intermediate roll axes 106 and the center of the pivots 39 is eighty inches. For the lowermost intermediate roll 114 , which has a maximum angular motion of about 17 degrees, and a maximum vertical motion of the roll axes of about twenty-four inches, or about 30 percent of the pivot radius. The roll has a maximum horizontal displacement of the roll axes of about 0.45 inches from the calender plane 107 , which is less than one percent of the pivot radius, with the actual displacement of the nip formed between the lowermost intermediate roll 114 and the bottom roll 26 , or the roll immediately above being displaced about a maximum of 0.41 inches from the calender plane 107 and it is this last displacement which controls the amount of lateral loads developed at the pivot arm 36 pivots 39 .
The intermediate roll 34 immediately above the lowermost intermediate roll 114 has a smaller vertical motion, approximately twenty-one and one half inches or slightly more than twenty-five percent of the pivot radius and proportionately less horizontal displacement. Less vertical motion is required of the intermediate rolls 34 as the top roll 28 is approached, so that the horizontal motion can be to less than one percent of the pivot radius, without necessarily causing the axis of the intermediate rolls 34 to pass twice through the calender plane 107 . The calender plane 107 could be tilted with respect to the vertical, in which case the horizontal and vertical displacements are measured as parallel and perpendicular to the calender plane.
It should be understood that the calender rolls 26 , 28 , 34 are supported on either end by mirror image frames, arms, and load support cylinders. The rolls having a typical cross machine direction width which is greater than the width of the paper web being calendered which, for an on-machine calender, may be several hundred inches wide.
It should be understood that the calender 20 may be constructed as a rebuild calender or as a new calender.
It should be understood that in the claims the term support frame refers to the structure to which the pivot arms are mounted, whether that is a weldment, a weldment plus an existing frame, or simply a frame, however constructed, which supports the pivot arms.
It should be understood that in the claims the terms support cylinders includes hydraulic cylinders, pneumatic cylinders, electric actuators, air rides/air bags, and other types of actuator.
It is understood that the invention is not limited to the particular construction and arrangement of parts herein illustrated and described, but embraces all such modified forms thereof as come within the scope of the following claims.
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A supercalender has a top roll, a bottom roll, and a plurality of intermediate rolls. The intermediate rolls are mounted to support frames by pivot arms. The pivot radius defined by the arms is at least about 2½ times the diameter of the largest intermediate roll. Hydraulic load support cylinders are arranged between the intermediate roll bearings and anchor points which are spaced away from the intermediate rolls, to allow greater movement without mechanical interference between hydraulic load support cylinders. The greater length of the pivot arms combined with a greater stroke of the load support cylinders allows the supercalender to accommodate filled rolls which change diameter substantially over their life, as the surface of the rolls is repeatedly turned down to refurbish the roll surface. The calender may be based on an existing calender of the closed A-frame type. One half of each A-frame in the machine direction is removed and a weldment is bolted to the track of each remaining frame along which the bearing housings of the calender rolls formally rode.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of priority from Taiwan patent application TW 103 124 194, filed Jul. 14, 2014, the contents of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a pulley for an alternator, and in particular, to a pulley for an automotive alternator.
An alternator is a type of generator that can produce an alternating current by converting mechanical energy into electrical energy. An automotive alternator converts mechanical energy of an engine into electrical energy to charge a battery, so as to supply electrical power to other electrical appliances on the automobile, and start a motor to rotate the engine.
An alternator generally has an annular stator and a rotor received in the annular stator. A wire is wound on the stator, and the rotor rotates rapidly in the stator so that the wire moves relative to a magnetic field generated by the rotor, and an induced electromotive force (voltage) is generated in the wire.
An automotive alternator is usually utilized by an engine driving a belt. The belt is wound on a pulley, and the pulley is connected to a rotor so as to drive the rotor to rotate. However, in conventional alternator design, when an engine starts, or accelerates or decelerates quickly in an instant, a waveform changes significantly at the moment the generator charges a battery, and it cannot be stabilized. In addition, one side of the belt wound on the pulley is tight, and the other side thereof is slack. The tension of the slack-side belt is low, and therefore a tensioner is disposed thereon to adjust the tension of the belt. However, when a rotation speed at which the engine transmits power changes suddenly, because the pulley of the generator is locked by a nut and the belt is made of a flexible material and cannot reflect the rotation speed immediately, a slip is easily caused between the belt and the pulley. Moreover, the fluctuation of the rotation speed causes the belt to bear not only a repeated stress but also a centrifugal force that is applied on the belt when the pulley rotates. The value of the centrifugal force changes with the rotation speed, and therefore the belt is often affected by adverse factors of an internal micro tension, which pulls the belt, and external large-amplitude shaking.
SUMMARY
The present invention provides a pulley for an alternator, which includes an outer wheel, provided with an axle hole at the center; a clutch wheel, fixedly disposed in the axle hole of the outer wheel and having a pivot hole; a hollow connecting shaft, having a first end and a second end, where the first end is rotatably disposed in the pivot hole of the clutch wheel, so that the hollow connecting shaft maintains a co-rotational relationship with the outer wheel in a first relative rotation direction by means of the clutch wheel, while in a second relative rotation direction, the hollow connecting shaft is disassociated from the co-rotational relationship with the outer wheel, and presents an idling state; and the second end of the hollow connecting shaft is provided with a first protruding portion; a hollow core shaft, having a first end and a second end, where the hollow core shaft is rotatably received in the outer wheel, and the second end of the hollow core shaft is rotatably arranged at the second end of the hollow connecting shaft; the second end of the hollow core shaft is provided with a second protruding portion, and the second protruding portion corresponds to the first protruding portion; the number of one of the first protruding portion and the second protruding portion is at least one, and the number of the other of the first protruding portion and the second protruding portion is at least two; and an elastic element, disposed between the second end of the hollow connecting shaft and the second end of the hollow core shaft.
When an external force drives the outer wheel to rotate, the outer wheel rotates relative to the hollow connecting shaft in the first relative rotation direction, and drives, through the clutch wheel, the hollow connecting shaft to rotate synchronously; the second end of the hollow connecting shaft presses the elastic element, and while being pressed, the elastic element pushes the second end of the hollow core shaft, thereby driving the hollow core shaft to rotate; and if a rotation angle of the hollow connecting shaft relative to the hollow core shaft exceeds a predetermined value at this time, the first protruding portion of the hollow connecting shaft contacts the second protruding portion of the hollow core shaft, thereby stopping relative rotation between the hollow connecting shaft and the hollow core shaft, so as to prevent the elastic element from being pressed excessively, and to set the hollow connecting shaft and the hollow core shaft in a synchronous co-rotational relationship. When the external force decreases or stops driving the outer wheel to rotate, the hollow core shaft continues to rotate due to inertia, and stretches the elastic element, and while being stretched, the elastic element pulls the second end of the hollow connecting shaft, thereby driving the hollow connecting shaft to rotate relative to the outer wheel in the second relative rotation direction, so that the hollow connecting shaft is disassociated from the co-rotational relationship with the outer wheel, and idles in the clutch wheel; and if a rotation angle of the hollow connecting shaft relative to the hollow core shaft exceeds a predetermined value at this time, the first protruding portion of the hollow connecting shaft contacts the second protruding portion of the hollow core shaft, thereby stopping relative rotation between the hollow connecting shaft and the hollow core shaft, so as to prevent the elastic element from being stretched excessively, and to set the hollow connecting shaft and the hollow core shaft in a synchronous co-rotational relationship.
According to another preferred embodiment of the present invention, the hollow core shaft passes through the hollow connecting shaft, and the first end of the hollow core shaft protrudes from the first end of the hollow connecting shaft; a tight-fit component is sleeved over an outer circumferential wall surface of the first end of the hollow core shaft in a tight-fit manner, and the tight-fit component is also tightly fit with an end surface of the first end of the hollow connecting shaft; therefore, the hollow connecting shaft and the hollow core shaft are made to corotate coaxially under a friction between the tight-fit component and the hollow connecting shaft and a friction between the tight-fit component and the hollow core shaft, and when the external force decreases or stops driving the outer wheel to rotate, the hollow core shaft continues to rotate due to inertia, and drives, through the tight-fit component, the hollow connecting shaft to rotate relative to the outer wheel in the second relative rotation direction, so that the hollow connecting shaft is disassociated from the co-rotational relationship with the outer wheel and idles in the clutch wheel.
According to another preferred embodiment of the present invention, the tight-fit component is a C-shaped retaining ring.
According to another preferred embodiment of the present invention, a first ball bearing is sleeved over the first end of the hollow core shaft, a second ball bearing is sleeved over the second end of the hollow core shaft, and the first ball bearing and the second ball bearing are disposed between the hollow core shaft and the outer wheel, so that the hollow core shaft is rotatable relative to the outer wheel.
According to another preferred embodiment of the present invention, three grooves are provided in a concave manner on an inner circumferential wall surface of the outer wheel, and an anaerobic adhesive is coated in the grooves, so that the clutch wheel, the first ball bearing, and the second ball bearing are separately tightly fit in the grooves, and are fixedly glued in the outer wheel by using the anaerobic adhesive.
According to another preferred embodiment of the present invention, a positioning casing is further sleeved over the first ball bearing, and an axial position of the pulley on the alternator is limited by the positioning casing.
According to another preferred embodiment of the present invention, an outer circumferential wall surface of the outer wheel is provided with a belt groove, for a belt to be wound on.
According to another preferred embodiment of the present invention, the belt is connected to a mechanical energy generating source, and the mechanical energy generating source provides an external force to drive the belt, thereby driving the outer wheel to rotate.
According to another preferred embodiment of the present invention, the mechanical energy generating source is an engine.
According to another preferred embodiment of the present invention, an inner circumferential wall surface of the hollow core shaft is provided with a threaded surface, the threaded surface is screwed with a joint lever having corresponding threads, and the joint lever is connected to a rotor, so that the hollow core shaft and the rotor corotate synchronously.
According to another preferred embodiment of the present invention, an inner circumferential wall surface of the outer wheel is provided with a step portion, for the clutch wheel to abut against, thereby limiting an axial displacement of the clutch wheel.
According to another preferred embodiment of the present invention, one end of the clutch wheel is provided with a positioning member, to limit an axial position of the clutch wheel, and the positioning member is a C-shaped retaining ring.
According to another preferred embodiment of the present invention, the elastic element is a torque spring, and a wire profile of the torque spring is circular, elliptical, or rectangular.
According to another preferred embodiment of the present invention, when the wire profile of the torque spring is rectangular, two end surfaces of the torque spring are grinded, so as to enhance axial positioning of the torque spring and control a free length of the torque spring more precisely.
According to another preferred embodiment of the present invention, two sides of the clutch wheel are each provided with an oil seal element, so as to prevent liquid in the clutch wheel from flowing into the outer wheel.
According to another preferred embodiment of the present invention, one side of one of the oil seal elements is provided with a positioning member, and the positioning member is sleeved over an inner side wall surface of the outer wheel in a tight-fit manner, to limit axial positions of the oil seal elements.
According to another preferred embodiment of the present invention, the positioning member is a C-shaped retaining ring.
According to another preferred embodiment of the present invention, an end, corresponding to the second end of the hollow core shaft, of the outer wheel is arranged with a dust cover, so as to prevent external dust from entering the outer wheel.
The present invention further provides a pulley for an alternator, which includes an outer wheel, provided with an axle hole at the center; a clutch wheel, fixedly disposed in the axle hole of the outer wheel and having a pivot hole; a hollow connecting shaft, having a first end and a second end, where the first end is rotatably disposed in the pivot hole of the clutch wheel, so that the hollow connecting shaft maintains a co-rotational relationship with the outer wheel in a first relative rotation direction by means of the clutch wheel, while in a second relative rotation direction, the hollow connecting shaft is disassociated from the co-rotational relationship with the outer wheel, and presents an idling state; and the second end of the hollow connecting shaft is provided with a first protruding portion; a hollow core shaft, having a first end and a second end, where the hollow core shaft is rotatably received in the outer wheel, and the hollow core shaft passes through the hollow connecting shaft; the first end of the hollow core shaft protrudes from the first end of the hollow connecting shaft, and the second end of the hollow core shaft is rotatably arranged on the second end of the hollow connecting shaft; the second end of the hollow core shaft is provided with a second protruding portion, and the second protruding portion corresponds to the first protruding portion; the number of one of the first protruding portion and the second protruding portion is at least one, and the number of the other of the first protruding portion and the second protruding portion is at least two; an elastic element, disposed between the second end of the hollow connecting shaft and the second end of the hollow core shaft; and a tight-fit component, sleeved over an outer circumferential wall surface of the first end of the hollow core shaft in a tight-fit manner and tightly fit with an end surface of the first end of the hollow connecting shaft, so that the hollow connecting shaft and the hollow core shaft corotate coaxially under a friction between the tight-fit component and the hollow connecting shaft and a friction between the tight-fit component and the hollow core shaft.
When an external force drives the outer wheel to rotate, the outer wheel rotates relative to the hollow connecting shaft in the first relative rotation direction, and drives, through the clutch wheel, the hollow connecting shaft to rotate synchronously, and the hollow connecting shaft drives, through the tight-fit component, the hollow core shaft to rotate; if the friction provided by the tight-fit component is insufficient to drive the hollow core shaft to rotate at this time, the second end of the hollow connecting shaft presses the elastic element, and while being pressed, the elastic element pushes the second end of the hollow core shaft, thereby driving the hollow core shaft to rotate; and if a rotation angle of the hollow connecting shaft relative to the hollow core shaft exceeds a predetermined value at this time, the first protruding portion of the hollow connecting shaft contacts the second protruding portion of the hollow core shaft, thereby stopping relative rotation between the hollow connecting shaft and the hollow core shaft, so as to prevent the elastic element from being pressed excessively, and to set the hollow connecting shaft and the hollow core shaft in a synchronous co-rotational relationship. When the external force decreases or stops driving the outer wheel to rotate, the hollow core shaft continues to rotate due to inertia, and drives, through the tight-fit component, the hollow connecting shaft to rotate relative to the outer wheel in the second relative rotation direction; and if the friction provided by the tight-fit component is insufficient to drive the hollow connecting shaft to rotate at this time, the hollow core shaft rotates relative to the hollow connecting shaft until the first protruding portion of the hollow connecting shaft contacts the second protruding portion of the hollow core shaft, thereby stopping relative rotation between the hollow connecting shaft and the hollow core shaft, and setting the hollow connecting shaft and the hollow core shaft in a synchronous co-rotational relationship.
According to another preferred embodiment of the present invention, when the external force decreases or stops driving the outer wheel to rotate, the hollow core shaft continues to rotate due to inertia, and drives, through the tight-fit component, the hollow connecting shaft to rotate relative to the outer wheel in the second relative rotation direction; if the friction provided by the tight-fit component is insufficient to drive the hollow connecting shaft to rotate at this time, the hollow core shaft stretches the elastic element, and while being stretched, the elastic element pulls the second end of the hollow connecting shaft, thereby driving the hollow connecting shaft to rotate relative to the outer wheel in the second relative rotation direction, so that the hollow connecting shaft is disassociated from the co-rotational relationship with the outer wheel; and if a rotation angle of the hollow connecting shaft relative to the hollow core shaft exceeds a predetermined value, the protruding portion of the hollow connecting shaft contacts the protruding portion of the hollow core shaft, thereby stopping relative rotation between the hollow connecting shaft and the hollow core shaft, so as to prevent the elastic element from being stretched excessively, and to set the hollow connecting shaft and the hollow core shaft in a synchronous co-rotational relationship.
According to another preferred embodiment of the present invention, the tight-fit component is a C-shaped retaining ring.
According to another preferred embodiment of the present invention, a first ball bearing is sleeved over the first end of the hollow core shaft, a second ball bearing is sleeved over the second end of the hollow core shaft, and the first ball bearing and the second ball bearing are disposed between the hollow core shaft and the outer wheel, so that the hollow core shaft is rotatable relative to the outer wheel.
According to another preferred embodiment of the present invention, three grooves are provided in a concave manner on an inner circumferential wall surface of the outer wheel, and an anaerobic adhesive is coated in the grooves, so that the clutch wheel, the first ball bearing, and the second ball bearing are separately tightly fit in the grooves, and are fixedly glued in the outer wheel by using the anaerobic adhesive.
According to another preferred embodiment of the present invention, a positioning casing is further sleeved over the first ball bearing, and an axial position of the pulley on the alternator is limited by the positioning casing.
According to another preferred embodiment of the present invention, an outer circumferential wall surface of the outer wheel is provided with a belt groove, for a belt to be wound on.
According to another preferred embodiment of the present invention, the belt is connected to a mechanical energy generating source, and the mechanical energy generating source provides an external force to drive the belt, thereby driving the outer wheel to rotate.
According to another preferred embodiment of the present invention, the mechanical energy generating source is an engine.
According to another preferred embodiment of the present invention, an inner circumferential wall surface of the hollow core shaft is provided with a threaded surface, the threaded surface is screwed with a joint lever having corresponding threads, and the joint lever is connected to a rotor, so that the hollow core shaft and the rotor corotate synchronously.
According to another preferred embodiment of the present invention, an inner circumferential wall surface of the outer wheel is provided with a step portion, for the clutch wheel to abut against, thereby limiting an axial displacement of the clutch wheel.
According to another preferred embodiment of the present invention, one end of the clutch wheel is provided with a positioning member, to limit an axial position of the clutch wheel, and the positioning member is a C-shaped retaining ring.
According to another preferred embodiment of the present invention, the elastic element is a torque spring, and a wire profile of the torque spring is circular, elliptical, or rectangular.
According to another preferred embodiment of the present invention, when the wire profile of the torque spring is rectangular, two end surfaces of the torque spring are grinded, so as to enhance axial positioning of the torque spring and control a free length of the torque spring more precisely.
According to another preferred embodiment of the present invention, two sides of the clutch wheel are each provided with an oil seal element, so as to prevent liquid in the clutch wheel from flowing into the outer wheel.
According to another preferred embodiment of the present invention, one side of one of the oil seal elements is provided with a positioning member, and the positioning member is sleeved over an inner side wall surface of the outer wheel in a tight-fit manner, to limit axial positions of the oil seal elements.
According to another preferred embodiment of the present invention, the positioning member is a C-shaped retaining ring.
According to another preferred embodiment of the present invention, an end, corresponding to the second end of the hollow core shaft, of the outer wheel is arranged with a dust cover, so as to prevent external dust from entering the outer wheel.
The present invention further provides an alternator having the pulley according to the present invention.
According to another preferred embodiment of the present invention, the alternator is used on a vehicle.
For better understanding of the detailed description of the present invention, the features and technical advantages of the present invention are described generally above. The following describes the additional features and advantages of the present invention. Persons skilled in the art should be aware that the disclosed concept and specific implementation manner can be easily used as a basis for modifying or designing other structures for implementing objectives the same as the present invention. Persons skilled in the art should also be aware that such equivalent structures do not depart from the spirit and scope of the present invention which are claimed in the patent application scope.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more thorough understanding of the present invention and advantages of the present invention, the following descriptions are provided with reference to the accompanying drawings, where:
FIG. 1 is a three-dimensional exploded view of a pulley for an alternator according to the present invention;
FIG. 2 is a sectional assembled view of a pulley for an alternator according to the present invention;
FIG. 3 is a schematic structural view of a hollow connecting shaft according to the present invention;
FIG. 4 is a schematic structural view of a hollow core shaft according to the present invention; and
FIG. 5 is a schematic view of a rotor of an alternator according to the present invention.
MEANING OF REFERENCE NUMERALS
10 Pulley
20 Joint lever
30 Rotor
110 Outer wheel
111 Axle hole
112 Belt groove
113 Step portion
120 Clutch wheel
121 Pivot hole
122 Housing
123 Rolling member
124 Elastic member
125 Cap
130 Hollow connecting shaft
131 First end of the hollow connecting shaft
132 Second end of the hollow connecting shaft
133 First protruding portion
134 Stop wall of the hollow connecting shaft
140 Hollow core shaft
141 First end of the hollow core shaft
142 Second end of the hollow core shaft
143 First ball bearing
144 Second ball bearing
145 Protruding ring of the hollow core shaft
146 Second protruding portion
147 Stop wall of the hollow core shaft
148 Threaded surface
150 Elastic element
160 Tight-fit component
161 Positioning gasket
162 C-shaped retaining ring
170 Positioning casing
171 Protruding ring of the positioning casing
181 Oil seal element
182 Oil seal element
183 Positioning member
184 Dust cover
185 Positioning member
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
The following embodiments describe the present invention in further detail. The embodiments are merely used to describe the present invention and illustrate the advantages of specific embodiments of the present invention, but it does not mean that the present invention is limited to such implementations.
FIG. 1 and FIG. 2 are respectively a three-dimensional exploded view and a sectional assembled view of a pulley for an alternator according to the present invention. As shown in FIG. 1 and FIG. 2 , a pulley 10 for an alternator according to the present invention mainly includes an outer wheel 110 , a clutch wheel 120 , a hollow connecting shaft 130 , a hollow core shaft 140 , an elastic element 150 , and a tight-fit component 160 . The outer wheel 110 is a wheel-shaped member provided with an axle hole 111 at the center, and is provided with a belt groove 112 on an outer circumferential wall surface thereof and a step portion 113 on an inner circumferential wall surface thereof. The clutch wheel 120 is annular, provided with a pivot hole 121 at the center, and fixedly disposed in the axle hole 111 of the outer wheel 110 . For example, a groove may be provided in a concave manner on the inner circumferential wall surface of the outer wheel 110 , and an anaerobic adhesive is coated in the groove so that the clutch wheel 120 can be fixedly connected to an inner circumferential wall surface of the axle hole 111 of the outer wheel 110 by means of tight fit and adhesion of the anaerobic adhesive. One end of the clutch wheel 120 abuts against the step portion 113 of the outer wheel 110 to limit an axial position of the clutch wheel 120 and to ensure that an end surface of the clutch wheel 120 is perpendicular to the hollow connecting shaft 130 and the hollow core shaft 140 , prevent axial displacement of the clutch wheel 120 during high-speed rotation, and moreover, provide an axial positioning reference during assembly of components in the outer wheel 110 , which facilitates positioning during the assembly.
The hollow connecting shaft 130 has a first end 131 and a second end 132 . The first end 131 is rotatably disposed in the clutch wheel 120 so that the hollow connecting shaft 130 can maintain a co-rotational relationship with the outer wheel 110 in a first relative rotation direction by means of the clutch wheel 120 (for example, the hollow connecting shaft 130 rotates anticlockwise relative to the outer wheel 110 ), and it is disassociated from the co-rotational relationship with the outer wheel 110 in a second relative rotation direction to enter an idling state (for example, the hollow connecting shaft 130 rotates clockwise relative to the outer wheel 110 ), and at this time, the hollow connecting shaft 130 rotates independently of the outer wheel 110 . The hollow connecting shaft 130 is provided with a first protruding portion 133 on the second end 132 , as shown in FIG. 3 .
In a preferred embodiment of the present invention, the clutch wheel 120 has a housing 122 , a plurality of rolling members 123 , a plurality of elastic members 124 , and two caps 125 . The clutch wheel 120 is provided with a positioning member 185 on an end opposite to the end abutting against the step portion 113 to limit the axial position of the clutch wheel 120 and prevent the caps 125 of the clutch wheel 120 from falling off. The positioning member may be a C-shaped retaining ring. For the detailed structure and operating principle of the clutch wheel 120 , reference may be made to Taiwan Patent Application No. 098129945 filed by the applicant on Sep. 4, 2009. However, the clutch wheel of the present invention is not limited thereto, and any speed-difference clutch apparatus capable of implementing the functions of the clutch wheel 120 described in the present invention may be designed as the clutch wheel 120 of the present invention. Moreover, in the present invention, two ends of the clutch wheel 120 are each provided with an oil seal element 181 / 182 so as to prevent a liquid (for example, a lubricating oil) in the clutch wheel 120 from permeating and polluting the interior of the pulley 10 . Furthermore, a positioning member 183 may be sleeved over one side of the oil seal element 182 . The positioning member 183 may be a C-shaped retaining ring, and may be sleeved over an inner side wall surface of the outer wheel 110 in a tight-fit manner, to limit axial positions of the oil seal elements 181 and 182 and the clutch wheel 120 .
The hollow core shaft 140 is disposed in the outer wheel 110 and has a first end 141 and a second end 142 . A first ball bearing 143 is sleeved over the first end 141 , and a second ball bearing 144 is sleeved over the second end 142 . The first ball bearing 143 and the second ball bearing 144 are both fixedly connected to the inner circumferential wall surface of the outer wheel 110 (for example, the outer wheel 110 may be provided with two grooves on the inner circumferential wall surface in a concave manner, and an anaerobic adhesive is coated in the grooves so that the first ball bearing 143 and the second ball bearing 144 can be fixedly connected to the inner circumferential wall surface of the axle hole 111 of the outer wheel 110 by means of tight fit and adhesion of the anaerobic adhesive) so that the hollow core shaft 140 is rotatable relative to the outer wheel 110 . In addition, the hollow core shaft 140 passes through the hollow connecting shaft 130 , and the first end 141 of the hollow core shaft 140 protrudes from the first end 131 of the hollow connecting shaft 130 . A protruding ring 145 is annularly arranged at the second end 142 of the hollow core shaft 140 . The protruding ring 145 is rotatably arranged on the second end 132 of the hollow connecting shaft 130 . A second protruding portion 146 is provided in a protruding manner in a direction towards the hollow connecting shaft 130 , and the second protruding portion 146 corresponds to the first protruding portion 133 so that after the hollow connecting shaft 130 and the hollow core shaft 140 rotate by a particular degree relative to each other, the first protruding portion 133 of the hollow connecting shaft 130 contacts the second protruding portion 146 of the hollow core shaft 140 , thereby stopping relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 . For example, when the hollow connecting shaft 130 is provided with two first protruding portions 133 at the second end 132 , and when the hollow core shaft 140 is provided with three second protruding portions 146 at the second end 142 , the hollow core shaft 140 can only rotate clockwise or anticlockwise by 120 degrees relative to the hollow connecting shaft 130 after being sleeved over the hollow connecting shaft 130 because relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 is stopped when the first protruding portions 133 contact the second protruding portions 146 .
The elastic element 150 is disposed between the second end 132 of the hollow connecting shaft 130 and the second end 142 of the hollow core shaft 140 . In a preferred embodiment of the present invention, the elastic element is a torque spring, and a wire profile of the torque spring may be circular, elliptical, or rectangular. When the wire profile of the torque spring is rectangular, two end surfaces of the torque spring may be grinded so as to enhance an axial positioning capability of the torque spring and control a free length of the spring more precisely. The hollow connecting shaft 130 is provided with a stop wall 134 in a concave manner on an inner circumferential wall surface of the second end 132 (as shown in FIG. 3 ) so that one end of the elastic element 150 can abut against the stop wall 134 , and the elastic element 150 may also be fixedly connected to the stop wall 134 . In addition, The hollow core shaft 140 is also provided with a stop wall 147 on an inner side of the protruding ring 145 of the second end 142 (as shown in FIG. 4 ) so that the other end of the elastic element 150 can abut against the stop wall 147 , and the elastic element 150 may also be fixedly connected to the stop wall 147 . When the two ends of the elastic element 150 are fixedly connected to the stop wall 134 of the hollow connecting shaft 130 and the stop wall 147 of the hollow core shaft 140 , relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 presses or stretches the elastic element 150 ; when the two ends of the elastic element 150 merely abut against but are not fixedly connected to the stop wall 134 of the hollow connecting shaft 130 or the stop wall 147 of the hollow core shaft 140 , relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 only presses the elastic element 150 .
The tight-fit component 160 is a C-shaped retaining ring; the C-shaped retaining ring is sleeved over the outer circumferential wall surface of the first end 141 of the hollow core shaft 140 in a tight-fit manner, and is tightly fit with a tail end surface of the first end 131 of the hollow connecting shaft 130 . Therefore, under a friction between the tight-fit component 160 and the end surface of the first end 131 of the hollow connecting shaft 130 and a friction between the tight-fit component 160 and the outer circumferential wall surface of the first end 141 of the hollow core shaft 140 , the hollow connecting shaft 130 and the hollow core shaft 140 drive each other and corotate coaxially, as shown in FIG. 3 .
A positioning casing 170 is further sleeved over the first ball bearing 143 , and the positioning casing 170 is a hollow annular pipe provided with a protruding ring 171 at one end; therefore, the protruding ring 171 penetrates the first ball bearing 143 and provides an abutting and cushioning function when the pulley 10 is installed on an alternator, and an axial position of the pulley 10 on the alternator is limited by the positioning casing 170 .
The hollow core shaft 140 is provided with a threaded surface 148 on an inner circumferential wall surface thereof, the threaded surface 148 may be screwed with a joint lever 20 having corresponding threads, and the joint lever 20 is connected to a rotor 30 of the alternator so that the hollow core shaft 140 and the rotor 30 corotate synchronously (as shown in FIG. 5 ). In addition, an end, corresponding to the second end 142 of the hollow core shaft 140 , of the outer wheel 110 is arranged with a dust cover 184 so as to prevent external dust from entering the outer wheel 110 .
With the structure described above, when a mechanical energy generating source provides an external force to drive the outer wheel 110 to rotate, the outer wheel 110 rotates relative to the hollow connecting shaft 130 in the first relative rotation direction and drives, through the clutch wheel 120 , the hollow connecting shaft 130 to rotate synchronously, and with the friction provided by the tight-fit component 160 , the hollow connecting shaft 130 drives the hollow core shaft 140 to rotate. At this time, if the friction provided by the tight-fit component 160 is insufficient to drive the hollow core shaft 140 to rotate, the hollow connecting shaft 130 rotates relative to the hollow core shaft 140 , which causes the stop wall 134 at the second end 132 of the hollow connecting shaft 130 to press the elastic element 150 , and while being pressed, the elastic element 150 pushes the stop wall 147 at the second end 142 of the hollow core shaft 140 , thereby driving the hollow core shaft 140 to rotate. At this time, if a relative rotation angle between the hollow connecting shaft 130 and the hollow core shaft 140 exceeds a predetermined value (for example, 120 degrees), the first protruding portion 133 of the hollow connecting shaft 130 contacts the second protruding portion 146 of the hollow core shaft 140 , thereby stopping relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 so as to avoid pressing the elastic element 150 excessively and damaging the structure thereof, and to set the hollow connecting shaft 130 and the hollow core shaft 140 in a synchronous co-rotational relationship; the hollow core shaft 140 also drives the rotor 30 to rotate so that the alternator generates an induced current.
In addition, if the outer wheel 110 is originally in a rotation state, when the mechanical energy generating source provides an external force to accelerate the rotation of the outer wheel 110 , an operating principle of the pulley 10 of the present invention is substantially the same as the aforementioned operating principle in the case of starting the outer wheel 110 to rotate, and therefore it is not repeated herein.
On the contrary, when the external force stops driving the outer wheel 110 to rotate, the hollow core shaft 140 continues to rotate due to inertia of the rotor 30 . At this time, the hollow core shaft 140 drives, by using the friction provided by the tight-fit component 160 , the hollow connecting shaft 130 to rotate relative to the outer wheel 110 in the second relative rotation direction so that the hollow connecting shaft 130 is disassociated from the co-rotational relationship with the outer wheel 110 . At this time, if the friction provided by the tight-fit component 160 is insufficient to drive the hollow connecting shaft 130 to rotate, the hollow core shaft 140 rotates relative to the hollow connecting shaft 130 ; if the elastic element 150 merely abuts against but is not fixedly connected to the hollow connecting shaft 130 and the hollow core shaft 140 , the hollow core shaft 140 keeps rotating relative to the hollow connecting shaft 130 until the second protruding portion 146 of the hollow core shaft 140 contacts the first protruding portion 133 of the hollow connecting shaft 130 , thereby stopping relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 and setting the hollow connecting shaft 130 and the hollow core shaft 140 in a synchronous co-rotational relationship so that the hollow connecting shaft 130 and the hollow core shaft 140 rotate relative to the outer wheel 110 in the second relative rotation direction.
If the elastic element 150 is fixedly connected to the hollow connecting shaft 130 and the hollow core shaft 140 , when the friction provided by the tight-fit component 160 is insufficient to drive the hollow connecting shaft 130 to rotate, the hollow core shaft 140 rotates relative to the hollow connecting shaft 130 and stretches the elastic element 150 , and while being stretched, the elastic element 150 pulls the second end 132 of the hollow connecting shaft 130 , thereby driving the hollow connecting shaft 130 to rotate relative to the outer wheel 110 in the second relative rotation direction so that the hollow connecting shaft 130 is disassociated from the co-rotational relationship with the outer wheel 110 . At this time, if rotation of the hollow connecting shaft 130 relative to the hollow core shaft 140 exceeds a predetermined value (for example, 120 degrees), the first protruding portion 133 of the hollow connecting shaft 130 contacts the second protruding portion 146 of the hollow core shaft 140 , thereby stopping relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 so as to avoid stretching the elastic element 150 excessively and damaging the structure thereof, and to set the hollow connecting shaft 130 and the hollow core shaft 140 in a synchronous co-rotational relationship so that the hollow connecting shaft 130 and the hollow core shaft 140 rotate relative to the outer wheel 110 in the second relative rotation direction.
In addition, if the external force driving the outer wheel 110 decreases, the operating principle of the pulley 10 of the present invention is substantially the same as the aforementioned operating principle in the case in which the outer wheel 110 stops rotating, and therefore it is not repeated herein.
In the pulley 10 of the present invention, a belt (not shown in the figure) may be wound on the belt groove 112 of the outer wheel 110 so that the mechanical energy generating source can provide an external force to drive the belt, thereby driving the outer wheel 110 to rotate. In addition, the pulley 10 of the present invention is applicable to an alternator system, such as a power generation system and an alternator system of a vehicle. The pulley of the present invention is especially suitable to be used as a stator structure of an automotive alternator. When the pulley of the present invention is applied to an automotive alternator, the mechanical energy generating source is an automobile engine.
In a preferred embodiment of the present invention, the tight-fit component 160 of the pulley 10 of the present invention may be omitted, and two ends of the elastic element 150 are fixedly connected to the stop wall 147 at the second end 142 of the hollow core shaft 140 and the stop wall 134 at the second end 132 of the hollow connecting shaft 130 . In this manner, when an external force drives the outer wheel 110 to rotate, the outer wheel 110 rotates relative to the hollow connecting shaft 130 in the first relative rotation direction and drives, through the clutch wheel 120 , the hollow connecting shaft 130 to rotate synchronously; the second end 132 of the hollow connecting shaft 130 presses the elastic element 150 , and while being pressed, the elastic element 150 pushes the stop wall 147 at the second end 142 of the hollow core shaft 140 , thereby driving the hollow core shaft 140 to rotate. At this time, if a rotation angle of the hollow connecting shaft 130 relative to the hollow core shaft 140 exceeds a predetermined value, the first protruding portion 133 of the hollow connecting shaft 130 contacts the second protruding portion 146 of the hollow core shaft 140 , thereby stopping relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 so as to prevent the elastic element 150 from being pressed excessively, setting the hollow connecting shaft 130 and the hollow core shaft 140 in a synchronous co-rotational relationship, and drive the rotor 30 to rotate.
On the contrary, when the external force decreases or stops driving the outer wheel 110 to rotate, the hollow core shaft 140 continues to rotate due to inertia of the rotor 30 and stretches the elastic element 150 , and while being stretched, the elastic element 150 pulls the second end 132 of the hollow connecting shaft 130 , thereby driving the hollow connecting shaft 130 to rotate relative to the outer wheel 110 in the second relative rotation direction so that the hollow connecting shaft 130 is disassociated from the co-rotational relationship with the outer wheel 110 and idles in the clutch wheel 120 . At this time, if a rotation angle of the hollow connecting shaft 130 relative to the hollow core shaft 140 exceeds a predetermined value, the first protruding portion 133 of the hollow connecting shaft 130 contacts the second protruding portion 146 of the hollow core shaft 140 , thereby stopping relative rotation between the hollow connecting shaft 130 and the hollow core shaft 140 so as to prevent the elastic element 150 from being stretched excessively, and to set the hollow connecting shaft 130 and the hollow core shaft 140 in a synchronous co-rotational relationship, in which the hollow connecting shaft 130 and the hollow core shaft 140 idle in the outer wheel 110 . In addition, in a preferred embodiment of the present invention, in the pulley 10 of the present invention, the first protruding portion 133 and the second protruding portion 146 may not be disposed, the protruding ring 145 at the second end 142 of the hollow core shaft 140 is directly sleeved over the second end 132 of the hollow connecting shaft 130 , and two ends of the elastic element 150 are fixedly connected to the stop wall 147 at the second end 142 of the hollow core shaft 140 and the stop wall 134 at the second end 132 of the hollow connecting shaft 130 . Therefore, when an external force drives the outer wheel 110 to rotate, the outer wheel 110 rotates relative to the hollow connecting shaft 130 in the first relative rotation direction and drives, through the clutch wheel 120 , the hollow connecting shaft 130 to rotate synchronously, and the hollow connecting shaft 130 drives, through the tight-fit component 160 , the hollow core shaft 140 to rotate. At this time, if the friction provided by the tight-fit component 160 is insufficient to drive the hollow core shaft 140 to rotate, the stop wall 134 at the second end 132 of the hollow connecting shaft 130 presses the elastic element 150 , and while being pressed, the elastic element 150 pushes the stop wall 147 at the second end 142 of the hollow core shaft 140 , thereby driving the hollow core shaft 140 to rotate, so as to drive the rotor 30 of the alternator to rotate.
On the contrary, when the external force decreases or stops driving the outer wheel 110 to rotate, the hollow core shaft 140 continues to rotate due to inertia of the rotor 30 and drives, through the tight-fit component 160 , the hollow connecting shaft 130 to rotate relative to the outer wheel 110 in the second relative rotation direction. At this time, if the friction provided by the tight-fit component 160 is insufficient to drive the hollow connecting shaft 130 to rotate, the hollow core shaft 140 stretches the elastic element 150 , and while being stretched, the elastic element 150 pulls the second end 132 of the hollow connecting shaft 130 , thereby driving the hollow connecting shaft 130 to rotate relative to the outer wheel 110 in the second relative rotation direction so that the hollow connecting shaft 130 is disassociated from the co-rotational relationship with the outer wheel 110 and idles in the clutch wheel 120 .
Further, in a preferred embodiment of the present invention, in the pulley 10 of the present invention, the tight-fit component 160 , the first protruding portion 133 , and the second protruding portion 146 may not be disposed; the protruding ring 145 at the second end 142 of the hollow core shaft 140 is directly sleeved over the second end 132 of the hollow connecting shaft 130 , and two ends of the elastic element 150 are fixedly connected to the stop wall 147 at the second end 142 of the hollow core shaft 140 and the stop wall 134 at the second end 132 of the hollow connecting shaft 130 . In this manner, when an external force drives the outer wheel 110 to rotate, the outer wheel 110 rotates relative to the hollow connecting shaft 130 in the first relative rotation direction and drives, through the clutch wheel 120 , the hollow connecting shaft 130 to rotate synchronously; the stop wall 134 at the second end 132 of the hollow connecting shaft 130 presses the elastic element 150 , and while being pressed, the elastic element 150 pushes the stop wall 147 at the second end 142 of the hollow core shaft 140 , thereby driving the hollow core shaft 140 to rotate.
On the contrary, when the external force decreases or stops driving the outer wheel 110 to rotate, the hollow core shaft 140 continues to rotate due to inertia of the rotor 30 and stretches the elastic element 150 , and while being stretched, the elastic element 150 pulls the second end 132 of the hollow connecting shaft 130 , thereby driving the hollow connecting shaft 130 to rotate relative to the outer wheel 110 in the second relative rotation direction so that the hollow connecting shaft 130 is disassociated from the co-rotational relationship with the outer wheel 110 and idles in the clutch wheel 120 .
Although the present invention and advantages thereof are described in detail above, it should be understood that variations, alternative solutions, and modifications can be made herein without departing from the spirit and scope of the present invention which are defined in the appended patent application scope. Moreover, the scope of the present invention is not limited to the specific implementations of the process, machine, product, material composition, means, method, and steps described in the specification. For example, persons skilled in the art can easily learn from the disclosure of the present invention that existing or to-be-developed processes, machines, products, material compositions, means, methods and steps that substantially implement the same function or substantially achieve the same result as the corresponding implementation manner described herein may be used. Correspondingly, the appended patent application scope is intended to cover such processes, machines, products, material compositions, means, methods or steps.
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The present invention relates to a pulley for an alternator, and in particular, to a pulley applicable to an automotive alternator. The pulley effectively mitigates the problem that a belt and a tension pulley of an alternator vibrate because a rotation speed of a vehicle engine changes, thereby improving the overall operating efficiency of the alternator and the service life of the working belt and the tension pulley.
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This application is a Divisional application of Ser. No. 12/223,789, filed Aug. 8, 2008, now allowed U.S. Pat. No. 7,799,780, which is a 371 application of PCT/EP2007/053583, filed Apr. 12, 2007.
FIELD OF THE INVENTION
The invention relates to novel heterocyclic compounds, processes for preparing the compounds, pharmaceutical products containing them, and their use as active pharmaceutical ingredients, especially as aldosterone synthase inhibitors.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates firstly to compounds of the general formula
in which
R is deuterium, halogen, or hydrogen; R 1 is aryl-C 0 -C 4 -alkyl or heterocyclyl-C 0 -C 4 -alkyl, which radicals may be substituted by 1-4 C 1 -C 8 alkoxy, C 1 -C 8 alkoxycarbonyl, C 1 -C 8 alkyl, C 0 -C 8 alkylcarbonyl, C 1 -C 8 alkylsulphonyl, optionally substituted aryl, aryl-C 0 -C 4 alkoxycarbonyl, cyano, halogen, optionally substituted heterocyclyl, hydroxy, nitro, oxide, oxo, tri-C 1 -C 4 alkylsilyl, trifluoromethoxy or trifluoromethyl; R 2 is a) deuterium, halogen, hydroxy, cyano or hydrogen; or b) C 2 -C 8 alkenyl, C 2 -C 8 alkynyl, C 1 -C 8 alkoxy, C 1 -C 4 alkoxycarbonyl-C 1 -C 4 alkyl, C 1 -C 8 alkyl, C 0 -C 4 alkylcarbonyl, aryl-C 0 -C 4 alkyl, carboxy-C 1 -C 4 alkyl, C 3 -C 8 cycloalkyl or heterocyclyl-C 0 -C 4 alkyl, which radicals may be substituted by 1-4 C 1 -C 8 alkoxy, C 1 -C 8 alkoxycarbonyl, C 1 -C 8 alkyl, C 0 -C 8 alkylcarbonyl, C 1 -C 8 alkylsulphonyl, optionally substituted aryl, aryl-C 0 -C 4 alkoxycarbonyl, cyano, halogen, optionally substituted heterocyclyl, hydroxy, nitro, oxide, oxo, tri-C 1 -C 4 alkylsilyl, trifluoromethoxy or trifluoromethyl; R 3 is C 1 -C 8 alkyl; Q is oxygen or sulphur; m is a number 0, 1 or 2; n is a number 0, 1 or 2;
and salts, preferably pharmaceutically acceptable salts, thereof
where
R 1 is not C 1 -C 8 alkyl-substituted aryl if R 2 is hydrogen.
The term aryl stands for a mono-, bi- or tricyclic aromatic hydrocarbon complying with the Hückel rule which generally comprises 6-14, preferably 6-10, carbon atoms and is for example phenyl, naphthyl, e.g. 1- or 2-naphthyl or anthracenyl. Aryl having 6-10 carbon atoms, in particular phenyl or 1- or 2-naphthyl, is preferred. The stated radicals may be unsubstituted or substituted one or more times, e.g. once or twice, in which case the substituent may be in any position, e.g. in the o, m or p position of the phenyl radical or in the 3 or 4 position of the 1- or 2-naphthyl radical, and there may also be a plurality of identical or different substituents present. Examples of substituents on aryl radicals or the preferred phenyl or naphthyl radicals are: C 1 -C 8 alkoxy, C 1 -C 8 alkoxycarbonyl, C 1 -C 8 alkyl, C 0 -C 8 alkylcarbonyl, C 1 -C 8 alkylsulphonyl, optionally substituted aryl, aryl-C 0 -C 4 alkoxycarbonyl, cyano, halogen, optionally substituted heterocyclyl, hydroxy, nitro, tri-C 1 -C 4 alkylsilyl, trifluoromethoxy or trifluoromethyl.
Aryl-C 0 -C 4 alkyl is for example phenyl, naphthyl or benzyl.
The term heterocyclyl stands for a saturated, partially saturated or unsaturated, 4-8-membered, particularly preferably 5-membered, monocyclic ring system, for a saturated, partially saturated or unsaturated, 7-12-membered, particularly preferably 9-10-membered, bicyclic ring system and also for a partially saturated or unsaturated, 9-12-membered tricyclic ring system which comprises an N, O, or S atom in at least one of the rings, it being possible for an additional N, O, or S atom to be present in one ring. Said radicals may be unsubstituted or substituted one or more times, e.g. once or twice, and there may also be a plurality of identical or different substituents present. Examples of substituents on heterocyclyl radicals are: C 1 -C 8 alkoxy, C 1 -C 8 alkoxycarbonyl, C 1 -C 8 alkyl, C 0 -C 8 alkylcarbonyl, C 1 -C 8 alkylsulphonyl, optionally substituted aryl, aryl-C 0 -C 4 alkoxycarbonyl, cyano, halogen, optionally substituted heterocyclyl, hydroxy, nitro, oxide, oxo, tri-C 1 -C 4 alkylsilyl, trifluoromethoxy or trifluoromethyl.
Saturated heterocyclyl-C 0 -C 4 alkyl is for example azepanyl, azetidinyl, aziridinyl, 3,4-dihydroxy-pyrrolidinyl, 2,6-dimethylmorpholinyl, 3,5-dimethylmorpholinyl, dioxanyl, [1,4]dioxepanyl, dioxolanyl, 4,4-dioxothiomorpholinyl, dithianyl, dithiolanyl, 2-hydroxymethylpyrrolidinyl, 4-hydroxypiperidinyl, 3-hydroxypyrrolidinyl, 4-methylpiperazinyl, 1-methylpiperidinyl, 1-methyl-pyrrolidinyl, morpholinyl, oxathianyl, oxepanyl, 2-oxo-azepanyl, 2-oxo-imidazolidinyl, 2-oxo-oxazolidinyl, 2-oxo-piperidinyl, 4-oxo-piperidinyl, 2-oxo-pyrrolidinyl, 2-oxo-tetrahydro-pyrimidinyl, 4-oxo-thiomorpholinyl, piperazinyl, piperidinyl, pyrrolidinyl, tetrahydrofuranyl, tetrahydropyranyl, tetrahydrothiophenyl, tetrahydrothiopyranyl, thiepanyl or thiomorpholinyl.
Partially saturated bicyclic heterocyclyl-C 0 -C 4 alkyl is for example 3,4-dihydro-2H-benzo[1,4]oxazinyl, 4,5,6,7-tetrahydrobenzofuranyl or 4,5,6,7-tetrahydrobenzothiazolyl.
Unsaturated bicyclic heterocyclyl-C 0 -C 4 alkyl is for example benzofuranyl, benzoimidazolyl, benzo[d]isothiazolyl, benzo[d]isoxazolyl, benzo[b]thiophen-yl, quinolinyl, imidazo[1,5-a]pyridinyl, indazolyl, indolyl or isoquinolinyl.
Unsaturated monocyclic heterocyclyl-C 0 -C 4 alkyl is for example imidazolyl, oxazolyl, pyridyl, pyrrolyl, tetrazolyl, thiazolyl or thiophenyl.
C 2 -C 8 alkenyl is for example ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, secondary butenyl, tertiary butenyl, or a pentenyl, hexenyl or heptenyl group.
C 2 -C 8 alkynyl is for example ethynyl, propynyl, butynyl, or a pentynyl, hexynyl or heptynyl group.
C 1 -C 8 alkoxy is for example C 1 -C 5 alkoxy such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, secondary butoxy, tertiary butoxy or pentoxy, but may also be a hexoxy or heptoxy group.
C 1 -C 8 alkoxycarbonyl is preferably C 1 -C 4 alkoxycarbonyl such as methoxycarbonyl, ethoxy-carbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, secondary butoxycarbonyl or tertiary butoxycarbonyl.
C 1 -C 4 alkoxycarbonyl-C 1 -C 4 alkyl is for example methoxycarbonylmethyl or ethoxycarbonyl-methyl, 2-methoxycarbonylethyl or 2-ethoxycarbonylethyl, 3-methoxycarbonylpropyl or 3-ethoxycarbonylpropyl or 4-ethoxycarbonylbutyl.
C 1 -C 8 alkyl may be straight-chain or branched and/or bridged and is for example methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, tertiary butyl, or a pentyl, hexyl or heptyl group.
C 0 -C 8 alkylcarbonyl or preferably C 0 -C 4 alkylcarbonyl is for example formyl, acetyl, propionyl, propylcarbonyl, isopropylcarbonyl, butylcarbonyl, isobutylcarbonyl, secondary butylcarbonyl or tertiary butylcarbonyl.
Carboxy-C 1 -C 4 alkyl is for example carboxymethyl, 2-carboxyethyl, 2- or 3-carboxypropyl, 2-carboxy-2-methylpropyl, 2-carboxy-2-ethylbutyl, or 4-carboxybutyl, in particular carboxy-methyl.
C 3 -C 8 cycloalkyl is preferably 3-, 5- or 6-membered cycloalkyl, such as cyclopropyl, cyclopentyl, cyclohexyl.
Halogen is for example fluorine, chlorine, bromine or iodine.
The compound groups mentioned below are not to be regarded as closed; on the contrary, parts of these compound groups may be replaced by one another or by the definitions given above, or be omitted, in a meaningful way, e.g. to replace general by more specific definitions. The definitions mentioned apply within the scope of general chemical principles such as, for example, the usual valencies of atoms.
R 1 is preferably deuterium or hydrogen.
R 1 is preferably aryl, very particularly preferably mono-, di- or tri-substituted phenyl or mono-, di- or tri-substituted naphthyl, or heterocyclyl, very particularly preferably optionally mono-, di- or tri-substituted benzofuranyl, benzo[b]thiophenyl, benzoimidazolyl, benzo[d]isothiazolyl, benzo[d]isoxazolyl, benzo[b]thiophenyl, imidazolyl, indazolyl, indolyl, oxazolyl, pyridyl, pyrrolyl, thiazolyl or thiophenyl.
R 2 is preferably C 1 -C 0 alkoxy, hydroxy, C 1 -C 0 alkyl, optionally substituted aryl-C 0 -C 4 alkyl, deuterium, halogen, cyano or hydrogen.
R 3 is preferably C 1 -C 4 alkyl.
n is preferably a number 0 or 1. n is particularly preferably the number 1.
Preferred substituents for aryl or heterocyclyl are C 1 -C 8 alkoxy, C 1 -C 8 alkyl, C 1 -C 8 alkyl-carbonyl, C 1 -C 8 alkylsulphonyl, optionally substituted aryl, cyano, halogen, optionally substituted heterocyclyl, nitro, oxide, trifluoromethyl, trifluoromethoxy or trimethylsilanyl. Very particularly preferred substituents for aryl or heterocyclyl are acetyl, bromine, chlorine, cyano, fluorine, methanesulphonyl, methoxy, nitro, oxazolyl, oxide, optionally substituted phenyl, optionally substituted tetrazolyl, optionally substituted thiazolyl or optionally substituted thiophenyl.
It is likewise preferred for R 1 to be a mono-, di- or tri-substituted unsaturated heterocyclyl substituent, where the substituents are preferably selected from the group consisting of C 1 -C 8 alkyl, C 1 -C 8 alkoxy, C 1 -C 8 alkoxycarbonyl, C 0 -C 8 alkylcarbonyl, C 1 -C 8 alkylsulphonyl, optionally substituted aryl, aryl-C 0 -C 4 alkoxycarbonyl, cyano, halogen, optionally substituted heterocyclyl, hydroxy, nitro, oxide, oxo, tri-C 1 -C 4 alkylsilyl, trifluoromethoxy and trifluoromethyl.
Particularly preferred compounds of the formula (I) are those of the general formula (Ia) and salts, preferably pharmaceutically acceptable salts, thereof,
in which R, R 1 , R 2 , R 3 , Q, m and n have the meanings indicated above for compounds of the formula (I), and where the above preferences apply analogously.
* designates an asymmetric carbon atom.
The compounds of the formula (I) or (Ia) which possess at least one asymmetric carbon atom can exist in the form of optically pure enantiomers, mixtures of enantiomers, or racemates. Compounds having a second asymmetric carbon atom can exist in the form of optically pure diastereomers, mixtures of diastereomers, diastereomeric racemates, mixtures of diastereomeric racemates, or meso compounds. The invention embraces all of these forms. Mixtures of enantiomers, racemates, mixtures of diastereomers, diastereomeric racemates, or mixtures of diastereomeric racemates can be fractionated by conventional methods, such as by racemate resolution, column chromatography, thin-layer chromatography, HPLC and the like.
The compounds of the formula (Ia) have at least one asymmetric carbon atom, which is labelled “*”. A compound of the formula (Ia) is to be understood as a compound having a specific configuration around the designated asymmetric carbon atom. If a synthesis method is used which leads to racemic compounds, the racemate resolution is carried out in accordance with conventional methods, such as via a chiral HPLC column. Compounds of the formula (Ia) as described in the present invention exhibit a pronounced aldosterone synthase and/or 11-β-hydroxylase inhibitory activity and a low aromatase inhibitory activity. The aforementioned aromatase inhibitory activity can, as the skilled worker is well aware and as described below, be comfortably determined using the commercial Cyp19 enzyme inhibition kit, preferably the Cyp19/methoxy-4-trifluoromethyl-coumarin (MFC) high throughput inhibition kit (Becton Dickinson Biosciences, San Jose, Calif., USA) as described hereafter. In the abovementioned inhibition kit, compounds of the formula (Ia) have an activity which is at least 10 times lower preferably 20 times lower, but more preferably 40 times lower than the compounds of the formula (Ia) with the opposite configuration around the asymmetric carbon atom labelled “*”. A lower inhibiting activity corresponds to a higher IC 50 value.
CYP19 inhibition:
Example number
IC 50 value [nM]
24
2769.0
antipode of 24
7.1
The expression “pharmaceutically acceptable salts” embraces salts with organic or inorganic acids, such as hydrochloric acid, hydrobromic acid, nitric acid, sulphuric acid, phosphoric acid, citric acid, formic acid, maleic acid, acetic acid, succinic acid, tartaric acid, methane-sulphonic acid, p-toluenesulphonic acid and the like. Salts of compounds containing salt-forming groups are, in particular, acid addition salts, salts with bases or else, if appropriate, if two or more salt-forming groups are present, are mixed salts or inner salts.
The compounds of the formula (I) or (Ia) can be prepared in an analogous manner to the preparation processes disclosed per se in the literature by JP63145286 (Scheme).
Details of the specific preparation variants can be found in the examples.
The compounds of the formula (I) or (Ia) can also be prepared in optically pure form. Separation into antipodes is possible by methods known per se, either, preferably, at an early stage in synthesis, by salt formation with an optically active acid such as, for example, (+)- or (−)-mandelic acid and separation of the diastereomeric salts by fractional crystallization, or, preferably, at a fairly late stage, by derivatization with a chiral auxiliary component, such as, for example, (+)- or (−)-camphanyl chloride and separation of the diastereomeric products by chromatography and/or crystallization and subsequent cleavage of the bond to the chiral auxiliary. The pure diastereomeric salts and derivatives can be analysed to determine the absolute configuration of the compound present, using customary spectroscopic methods, with single-crystal X-ray spectroscopy representing one particularly appropriate method.
Salts are primarily the pharmaceutically acceptable or non-toxic salts of compounds of the formula (I) or (Ia). Such salts are formed for example by compounds of the formula (I) or (Ia) containing an acidic group, such as a carboxyl or sulpho group and are, for example, salts thereof with suitable bases, such as non-toxic metal salts derived from metals of group Ia, Ib, IIa and IIb of the Periodic Table of the Elements, such as alkali metal salts, especially lithium, sodium or potassium salts, alkaline earth metal salts, magnesium or calcium salts for example, and also zinc salts or ammonium salts, and additionally salts formed with organic amines, such as unsubstituted or hydroxyl-substituted mono-, di- or trialkylamines, especially mono-, di- or tri-lower alkylamines, or with quaternary ammonium bases, e.g. methyl-, ethyl-, diethyl- or triethylamine, mono-, bis- or tris(2-hydroxyl-lower alkyl)amines, such as ethanolamine, diethanolamine or triethanolamine, tris(hydroxylmethyl)methylamine or 2-hydroxyl-tertiary-butylamine, N,N-di-lower alkyl-N-(hydroxyl-lower alkyl)amine, such as N,N-di-N-dimethyl-N-(2-hydroxylethyl)amine, or N-methyl-D-glucamine, or quaternary ammonium hydroxides, such as tetrabutylammonium hydroxide. The compounds of the formula (I) or (Ia) containing a basic group, such as an amino group, can form acid addition salts, with suitable inorganic acids for example, such as hydrohalic acid, such as hydrochloric acid, hydrobromic acid, or sulphuric acid with replacement of one or both protons, phosphoric acid with replacement of one or more protons, orthophosphoric acid or metaphosphoric acid for example, or pyrophosphoric acid with replacement of one or more protons, or with organic carboxylic, sulphonic or phosphonic acids or N-substituted sulphamic acids, e.g. acetic acid, propionic acid, glycolic acid, succinic acid, maleic acid, hydroxylmaleic acid, methylmaleic acid, fumaric acid, malic acid, tartaric acid, gluconic acid, glucaric acid, glucuronic acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, salicylic acid, 4-aminosalicylic acid, 2-phenoxybenzoic acid, 2-acetoxybenzoic acid, embonic acid, nicotinic acid, isonicotinic acid, and also amino acids, such as the α-amino acids specified earlier on, and also methanesulphonic acid, ethane-sulphonic acid, 2-hydroxylethanesulphonic acid, ethane-1,2-disulphonic acid, benzene-sulphonic acid, 4-toluenesulphonic acid, naphthalene-2-sulphonic acid, 2- or 3-phospho-glycerate, glucose 6-phosphate, N-cyclohexylsulphamic acid (to form cyclamates), or with other acidic organic compounds, such as ascorbic acid. Compounds of the formula (I) or (Ia) containing acidic and basic groups can also form inner salts.
Isolation and purification can also be carried out using pharmaceutically unsuitable salts.
The compounds of the formula (I) or (Ia) also include those compounds in which one or more atoms have been replaced by their stable, non-radioactive isotopes: for example, a hydrogen atom by deuterium.
Prodrug derivatives of the presently described compounds are derivatives thereof which when employed in vivo release the original compound as a result of a chemical or physiological process. A prodrug may be converted into the original compound, for example, when a physiological pH is reached or as a result of enzymatic conversion. Examples of possible prodrug derivatives include esters of freely available carboxylic acids, S- and O-acyl derivatives of thiols, alcohols or phenols, the acyl group being defined as above. Preference is given to pharmaceutically useful ester derivatives which are converted by solvolysis in physiological medium into the original carboxylic acid, such as, for example, lower alkyl esters, cycloalkyl esters, lower alkenyl esters, benzyl esters, mono- or disubstituted lower alkyl esters, such as lower ω-(amino, mono- or dialkylamino, carboxyl, lower alkoxycarbonyl)-alkyl esters or such as lower α-(alkanoyloxy, alkoxycarbonyl or dialkylaminocarbonyl)alkyl esters; pivaloyloxymethyl esters and similar esters are conventionally used as ester derivatives of this kind.
Because of the close relationship between a free compound, a prodrug derivative and a salt compound, a defined compound in this invention also includes its prodrug derivative and salt form, insofar as this is possible and appropriate.
Aldosterone is a steroidal hormone which is synthesized in the zona glomerulosa cells of the adrenal cortex by the enzyme aldosterone synthase (CYP11B2). Aldosterone production and secretion is regulated by the adrenocorticotropic hormone (ACTH), angiotensin II, potassium and sodium ions. The primary biological function of aldosterone is the regulation of the salt balance, with aldosterone controlling the reabsorption of sodium ions from the renal filtrate and the secretion of potassium ions into the renal filtrate. The state of excessive aldosterone secretion, also called hyperaldosteronism, can lead to high blood pressure, hypokalaemia, alkalosis, muscle weakness, polyuria, polydipsia, oedemas, vasculitis, increased collagen formation, fibrosis and endothelial dysfunction.
The chemical compounds described in this invention inhibit the cytochrome P450 enzyme aldosterone synthase (CYP11B2) and can therefore be used to treat states induced by aldosterone. The compounds described can be employed for preventing, for delaying the progression of or treating states such as hypokalaemia, hypertension, congestive heart failure, acute and—in particular—chronic renal failure, cardiovascular restenosis, athero-sclerosis, metabolic syndrome (syndrome X), adiposity (obesity), vasculitis, primary and secondary hyperaldosteronism, nephropathy, myocardial infarction, coronary heart disease, increased collagen formation, fibrosis, vascular and coronary tissue changes (remodelling) secondary to high blood pressure, endothelial dysfunction, and oedemas secondary to cirrhosis, nephrosis and congestive heart failure.
Cortisol is a steroidal hormone which is synthesized almost exclusively in the zona fasciculata cells of the adrenal cortex by the cytochrome P450 enzyme 11-β-hydroxylase (CYP11B1). Cortisol production is regulated by ACTH. The primary biological function of cortisol is to regulate the production and the provision of carbohydrates for the brain and other metabolically active tissues. Increased cortisol production and secretion is a normal physiological response to stress and leads to the essential mobilization of fats, proteins and carbohydrates to cover increased physical energy demand. Chronically excessive cortisol release describes the condition of Cushing's syndrome. Cushing's syndrome may come about on the one hand as a result of cortisol hypersynthesis, which may be generated by an adrenocortical tumour, or on the other hand as the consequence of excessive stimulation of the adrenal cortex by ACTH. The first form is referred to as primary hypercortisolism, the second form as secondary hypercortisolism. An excessive and persistent cortisol secretion may also accompany a stress response, which can lead to depression and the suppression of the immune system.
The chemical compounds described in this invention inhibit the enzyme 11-β-hydroxylase (CYP11B1) and may therefore, owing to the inhibition of cortisol synthesis, be employed for preventing, for delaying the progression of or treating Cushing's syndrome and also the physical and mental consequences of excessive and persistent cortisol secretion in states of stress.
The inhibition of aldosterone synthase (CYP11B2), as well as 11-β-hydroxylase (Cyp11B1) and aromatase (Cyp19) by herein described compounds may be measured by the following in vitro assay.
The cell line NCI-H295R was originally derived from an adrenal carcinoma and was subsequently characterized in the literature for the inducible secretion of steroidal hormones and the presence of the key enzymes necessary for steroidogenesis. These include Cyp11A (cholesterol side-chain cleavage), Cyp11B1 (steroid 11β-hydroxylase), Cyp11B2 (aldo-sterone synthase), Cyp17 (steroid 17α-hydroxylase and 17,20 lyase), Cyp19 (aromatase), Cyp21B2 (steroid 21-hydroxylase) and 3β-HSD (hydroxysteroid dehydrogenase). The cells have the physiological characteristics of zonally undifferentiated human fetal adrenal cells, with the ability to produce the steroid hormones of each of the three phenotypically distinct zones found in the adult adrenal cortex.
The NCI-H295R cells (American Type Culture Collection, ATCC, Rockville, Md., USA) are cultured in Dulbecco's Modified Eagle'Ham F-12 medium (DME/F12) that is supplemented with Ultroser SF serum (Soprachem, Cergy-Saint-Christophe, France) as well as insulin, transferrin, selenite (I-T-S, Becton Dickinson Biosiences, Franklin Lakes, N.J., USA) and antibiotics in 75 cm 2 cell culture flasks at a temperature of 37° C. and a 95% air/5% CO 2 humidified atmosphere. The cells are subsequently transferred to a 24-well plate and seeded in the presence of DME/F12 medium that is supplemented with 0.1% bovine serum albumin instead of Ultroser SF serum. The experiment is initiated by incubating the cells for 72 hours in DME/F12 medium supplemented with 0.1% bovine serum albumin and test compounds in the presence of cell stimulatory agents. The test compound is added in a concentration range of 0.2 nanomolar to 20 micromolar. Angiotensin-II (e.g. at 10 or 100 nanomolar concentration), potassium ions (e.g. at 16 millimolar), forskolin (e.g. at 10 micromolar) or a combination of two agents may serve as cell-stimulatory agents. The cellular secretion of aldosterone, cortisol, corticosterone and estradiol/estrone into the cell culture medium can be quantitatively assessed with commercially available radioimmunoassays and specific anti-bodies (e.g. Diagnostics Products Corporation, Los Angeles, Calif., USA) according to the manufacturer's instructions.
The degree of secretion of a selective steroid is used as a measure of enzyme activity, respectively enzyme inhibition, in the presence or absence of a test compound. The dose-dependent enzyme inhibitory activity of a compound is reflected in an inhibition curve that is characterized by an IC 50 value. The IC 50 values for active test compounds are generated by simple linear regression analysis to establish inhibition curves without data weighting. The inhibition curve is generated by fitting a 4-parameter logistic function to the raw data of the samples using the least squares approach. The function is described as follows:
Y =( d−a )/((1+( x/c ) −b )+ a )
with:
a=minimum
b=slope
c=IC 50
d=maximum
x=inhibitor concentrations
The compounds of the present invention show in the herein described in vitro test systems inhibitory activities with IC 50 values for aldosterone synthesis inhibition ranging from 10 −4 to 10 −10 mol/l, and IC 50 values for cortisol synthesis inhibition ranging from 10 −4 to 10 −10 mol/l.
Additionally, the in vitro inhibition of aromatase activity of the compounds of the present invention can be demonstrated by using a commercial Cyp19 enzyme inhibition kit. The Cyp19/methoxy-4-trifluoromethyl-coumarin (MFC) high throughput inhibition kit (Becton Dickinson Biosciences, San Jose, Calif., USA), for example, is designed to screen for potential inhibitors of Cyp19 catalytic activity in a 96-well format. The kit includes recombinant human Cyp19 enzyme in the form of supersomes, a fluorescent P450 substrate, an NADPH regenerating system, a reaction buffer and a stop reagent. MFC, the fluorogenic substrate is rapidly converted by Cyp19 supersomes to the highly fluorescent product 7-hydroxy-4-trifluoromethyl coumarin (7-HFC). The execution of the assay in the presence of various concentrations of inhibitor compounds ranging from 0.2 nanomolar to 20 millimolar occurs according to the manufacturer's instructions.
The inhibition curve is generated by fitting a 4-parameter logistic function to the raw data of the samples using the least squares approach. The function is described as follows:
Y= ( d - a )/((1+( x/c ) −b )+ a )
with:
a=minimal data values
b=slope
c=IC 50
d=maximal data values
x=inhibitor concentrations
The aldosterone- and corticosterone-suppressing activity of herein described compounds may be assessed with the following in vivo protocol.
Adult male Wistar rats weighing between 250 and 350 grams are kept under the usual 12-hour light and 12-hour dark conditions at a temperature of 23° C.±2° C. On the first day of the experiment, the animals receive a subcutaneous injection of a depot ACTH product in a dose of 1.0 mg/kg weight (SYNACTHEN-Depot, Novartis, Basel, CH) 16 hours prior to the administration of a test compound. Pilot studies showed that this ACTH dose significantly increased plasma aldosterone and corticosterone levels by 5- to 20-fold over a period of at least 18 hours. An alternative method to stimulate aldosterone secretion consists in subjecting rats to a low salt diet for 48 hours and applying the diuretic furosemide at 10 mg/kg by subcutaneous or intraperitoneal administration 16 hours, respectively 2 hours prior to the start of the experiment. On the second day of the experiment, the animals are divided into test groups of 5 animals and subjected to a first bleed 1 hour prior to the administration of test compound. Subsequently, and 16 hours after the injection of the ACTH product, the animals receive either vehicle or test compound dissolved in vehicle in a variable dose range from 0.02 to 20 mg/kg by oral gavage. The animals are bled two more times from the vena subclavia under isoflurane anaesthesia 2 and 6 hours after dosing. The blood is collected in heparin-treated tubes. The plasma samples are obtained by centrifugation and stored at −20° C. An alternative method to bleed animals time-dependently consists in using animals that are chronically carotid catheterized which allows the periodical sampling of up to 0.2 ml of blood using an AccuSampler (DiLab Europe, Lund, Sweden). The blood sampling with the AccuSampler may occur 1 hour prior to the administration of a test compound and 2, 4, 6, 8, 12, 16 and 24 hours thereafter. The blood samples are anticoagulated with heparin and centrifuged. The aldosterone and corticosterone concentrations of the plasma samples can be determined with a radioimmunoassay as described above for the in vitro test systems.
The selective suppression of plasma steroid levels as for instance aldosterone in comparison to corticosterone may serve as a measure for in vivo bioavailability and pharmacodynamic enzyme inhibitory activity of the herein described compounds. The evaluation of the data may occur relative to the application of vehicle or quantitatively by determination of the area under the curve (AUC).
Examples of suppression of aldosterone and corticosterone levels:
Compound
Dose
Aldosterone levels
Corticosterone levels
of Example
(mg/kg p.o.)
(% change + at 2 h)
(% change + at 2 h)
2
4
−56
−22
4
4
−19
−10
18
4
−33
4
19
4
−65
1.7
+ The resulting changes in plasma aldosterone, respectively corticosterone, levels upon oral administration of a test compound are expressed as percent (%) change that is defined by the ratio of the [(plasma steroid level 2 hours after compound administration) − (plasma steroid level 1 hour prior to compound administration)] divided by (plasma steroid level 1 hour prior to compound administration).
In order to achieve the desired effects in a patient to be treated, the compounds of the present invention can be administered orally or enterally, such as, for example, intravenously, intraperitoneally, intramuscularly, rectally, subcutaneously or else by direct injection of the active substance locally into tissues or tumours. The term patient encompasses warm-blooded species and mammals such as, for example, human, primate, bovine, dog, cat, horse, sheep, mouse, rat and pig. The compounds can be administered as pharmaceutical product or be incorporated into an administration device which ensures sustained release of the compound. The amount of substance to be administered can vary over a wide range and represent every effective dose. Depending on the patient to be treated or the condition to be treated and mode of administration, the dose of the effective substance each day can be between about 0.005 and 50 milligrams per kilogram of body weight, but is preferably between about 0.05 and 5 milligrams per kilogram of body weight each day.
For oral administration, the compounds can be formulated in solid or liquid pharmaceutical forms such as, for example, as capsules, pills, tablets, coated tablets, granules, powders, solutions, suspensions or emulsions. The dose of a solid pharmaceutical form can be one usual hard gelatine capsule which may be filled with active ingredients and excipients such as lubricants and fillers, such as, for example, lactose, sucrose and maize starch. Another form of administration may be represented by tableting of the active substance of the present invention. The tableting can take place with conventional tableting excipients such as, for example, lactose, sucrose, maize starch, combined with binder from gum acacia, maize starch or gelatine, disintegrants such as potato starch or crosslinked polyvinylpyrrolidone (PVPP) and lubricants such as stearic acid or magnesium stearate.
Examples of excipients suitable for soft gelatine capsules are vegetable oils, waxes, fats, semisolid and liquid polyols etc.
Examples of excipients suitable for producing solutions and syrups are water, polyols, sucrose, invert sugar, glucose etc.
For rectal administration, the compounds can be formulated in solid or liquid pharmaceutical forms such as, for example, suppositories. Examples of excipients suitable for suppositories are natural or hardened oils, waxes, fats, semiliquid or liquid polyols etc.
For parenteral administration, the compounds can be formulated as injectable dosage of the active ingredient in a liquid or suspension. The preparations usually comprise a physiologically tolerated sterile solvent which may comprise a water-in-oil emulsion, with or without surfactant, and other pharmaceutically acceptable excipients. Oils which can be used for such preparations are paraffins and triglycerides of vegetable, animal or synthetic origin, such as, for example, peanut oil, soya oil and mineral oil. Injectable solutions generally comprise liquid carriers such as, preferably, water, saline, dextrose or related sugar solutions, ethanol and glycols such as propylene glycol or polyethylene glycol.
The substances may be administered as transdermal patch system, as depot injection or implant if the formulation makes sustained delivery of the active ingredient possible. The active substance can be compressed as granules or to narrow cylinders and be administered subcutaneously or intramuscularly as depot injection or implant.
The pharmaceutical products may in addition also comprise preservatives, solubilizers, viscosity-increasing substances, stabilizers, wetting agents, emulsifiers, sweeteners, colorants, aromatizing agents, salts to change the osmotic pressure, buffers, coating agents or antioxidants. They may also comprise other therapeutically valuable substances too.
The compounds of the invention described herein permit the following methods of use:
as therapeutic combination in the form of a product or of a kit which is composed of individual components consisting of a compound described herein, in free form or as pharmaceutically acceptable salt, and at least one pharmaceutical form whose active ingredient has a blood pressure-lowering, an inotropic, an antidiabetic, an obesity-reducing or a lipid-lowering effect, which can be used either simultaneously or sequentially. The product and the kit may comprise instructions for use. as method for combined use, such as, for example, in simultaneous or sequential succession, of a therapeutically effective amount of a compound described herein, in free or in pharmaceutically acceptable salt form, and of a second active ingredient with blood pressure-lowering, inotropic, antidiabetic, obesity-reducing or lipid-lowering effect.
The compounds described herein and their pharmaceutically acceptable salts can be used in combination with
(i) one or more blood pressure-lowering active ingredients, as such for example:
renin inhibitors such as aliskiren; angiotensin II receptor blockers such as candesartan, irbesartan, olmesartan, losartan, valsartan, telmisartan etc.; ACE inhibitors such as quinapril, ramipril, trandolapril, lisinopril, captopril, enalapril etc.; calcium antagonists such as nifedipine, nicardipine, verapamil, isradipine, nimodipine, amlodipine, felodipine, nisoldipine, diltiazem, fendiline, flunarizine, perhexiline, gallopamil etc.; diuretics such as hydrochlorothiazide, chlorothiazide, acetazolamide, amiloride, bumetanide, benzthiazide, etacrynic acid, furosemide, indacrinone, metolazone, triamterene, chlorthalidone, etc.; aldosterone receptor blockers such as spironolactone, eplerenone; endothelin receptor blockers such as bosentan; phosphodiesterase inhibitors such as amrinone, sildenafil; direct vasodilators such as dihydralazine, minoxidil, pinacidil, diazoxide, nitroprusside, flosequinan etc.; α- and β-receptor blockers such as phentolamine, phenoxybenzamine, prazosin, doxazosin, terazosin, carvedilol, atenolol, metoprolol, nadolol, propranolol, timolol, carteolol etc.; neutral endopeptidase (NEP) inhibitors; sympatholytics such as methyldopa, clonidine, guanabenz, reserpine
(ii) one or more agents having inotropic activity, as such for example:
cardiac glycosides such as digoxin; β-receptor stimulators such as dobutamine; thyroid hormone such as thyroxine
(iii) one or more agents having antidiabetic activity, as such for example:
insulins such as insulin aspart, insulin human, insulin lispro, insulin glargine and further fast-, medium- and long-acting insulin derivatives and combinations insulin sensitizers such as rosiglitazone, pioglitazone; sulphonylureas such as glimepiride, chlorpropamide, glipizide, glyburide etc.; biguanides such as metformin; glucosidase inhibitors such as acarbose, miglitol; meglitinides such as repaglinide, nateglinide;
(iv) one or more obesity-reducing ingredients, as such for example:
lipase inhibitors such as orlistat; appetite suppressants such as sibutramine, phentermine;
(v) one or more lipid-lowering ingredients, such as, for example,
HMG-CoA reductase inhibitors such as lovastatin, fluvastatin, pravastatin, atorvastatin, simvastatin, rosuvastatin etc.; fibrate derivatives such as fenofibrate, gemfibrozil etc.; bile acid-binding active ingredients such as colestipol, colestyramine, colesevelam; cholesterol absorption inhibitors such as ezetimibe; nicotinic acid such as niacin
and other agents which are suitable for the treatment of high blood pressure, heart failure or vascular disorders associated with diabetes and renal disorders, such as acute or chronic renal failure, in humans and animals. Such combinations can be used separately or in products which comprise a plurality of components.
The compounds described herein and their pharmaceutically acceptable salts can additionally be used in combination with
(i) a diagnostic test system which permits quantitative determination of the plasma aldosterone level (PAC, plasma aldosterone concentration) (ii) a diagnostic test system which permits quantitative determination of the plasma renin level (PRC, plasma renin concentration) (iii) a diagnostic test system which permits quantitative determination of the plasma renin activity (PRA, plasma renin activity) (iv) a diagnostic test system which permits quantitative determination of the plasma aldosterone/renin level (ARC, aldosterone renin concentration) (v) a diagnostic test system which permits quantitative determination of the plasma aldosterone/renin activity (ARR, aldosterone to renin activity ratio) (vi) a diagnostic test system which permits quantitative determination of the plasma cortisol level (PCC, plasma cortisol concentration)
Such diagnosis-therapy combinations can be used separately or in products which comprise a plurality of components.
EXAMPLES
The following examples illustrate the present invention. All temperatures are stated in degrees Celsius, pressures in mbar. Unless mentioned otherwise, the reactions take place at room temperature. The abbreviation “Rf=xx(A)” means for example that the Rf is found in solvent system A to have the value xx. The proportion of solvents to one another is always stated in fractions by volume. Chemical names of end products and intermediates were generated with the aid of the AutoNom 2000 (Automatic Nomenclature) program.
HPLC gradient on Hypersil BDS C-18 (5 μm); column: 4×125 mm:
90% water*/10% acetonitrile*to 0% water*/100% acetonitrile*in 5 minutes+2.5 minutes (1.5 ml/min)
The abbreviations used are as follows:
Rf ratio of distance travelled by a substance to distance of the eluent from the starting point in thin-layer chromatography Rt retention time of a substance in HPLC (in minutes) m.p. melting point (temperature)
Example 1
4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile
A solution of 1.20 mmol of 2-[(4-cyanophenyl)-(3H-imidazol-4-yl)methoxy]ethyl methane-sulphonate in 10 ml of acetonitrile is heated to reflux for 24 hours. The reaction mixture is cooled to room temperature and evaporated. The title compound is obtained as a white solid from the residue by flash chromatography (SiO 2 60F). Rf=0.14 (dichloromethane-2M ammonia in ethanol 95:5); Rt=4.29.
The starting materials are prepared as follows:
a) 2-[(4-Cyanophenyl)-(3H-imidazol-4-yl)methoxy]ethyl methanesulphonate
1.44 mmol of diisopropylethylamine and 1.20 mmol of methanesulphonyl chloride are added to a solution of 1.20 mmol of 4-[(2-hydroxyethoxy)-(3H-imidazol-4-yl)methyl]benzonitrile in 10 ml of dichloromethane at 0° C. The reaction mixture is stirred at 0° C. for 3 hours, tipped into water and extracted with dichloromethane. The combined organic phases are washed with brine, dried over sodium sulphate and evaporated. The crude title compound is used without further purification in the next stage.
b) 4[(2-Hydroxyethoxy)-(3H-imidazol-4-yl)methyl]benzonitrile
2.45 mmol of sodium borohydride are added to a solution of 1.63 mmol of ethyl [(4-cyano-phenyl)-1-(trityl-1H-imidazol-4-yl)methoxy]acetate in 10 ml of ethanol at room temperature. The reaction mixture is stirred at room temperature for 16 hours and then evaporated. The residue is taken up in dichloromethane and saturated aqueous sodium bicarbonate solution, the phases are separated, and the aqueous phase is back-extracted with dichloromethane. The combined organic phases are dried with sodium sulphate and evaporated. The title compound is obtained as a white solid from the residue by flash chromatography (SiO 2 60F). Rf=0.10 (ethyl acetate-heptane 1:2); Rt=7.39.
c) Ethyl [(4-cyanophenyl)-(1-trityl-1H-imidazol-4-yl)methoxy]acetate
5.00 mmol of 4-[hydroxy-(1-trity-1H-imidazol-4-yl)methyl]benzonitrile are added to a mixture of 6.50 mmol of sodium hydride (60% dispersion in paraffin) in 20 ml of N,N-dimethyl-formamide at 0° C. The reaction mixture is stirred at 0° C. for 1 hour and then bromoacetic acid is added dropwise. The reaction mixture is stirred at room temperature for 16 hours, poured into water and extracted with tert-butyl methyl ether. The combined organic phases are washed with brine, dried with sodium sulphate and evaporated. The title compound is obtained as an amber-coloured oil from the residue by flash chromatography (SiOhd 2 60F). Rf=0.42 (ethyl acetate-heptane 1:2); Rt=8.00.
d) 4-[Hydroxy-(1-trityl-1H-imidazol-4-yl)methyl]benzonitrile
A solution of 14.80 mmol of 4-iodobenzonitrile [3058-39-7] in 20 ml of tetrahydrofuran is cooled to −30° C., and 14.80 mmol of i-propylmagnesium chloride (2M in tetrahydrofuran) are added. The mixture is stirred at −30° C. for 60 minutes and a solution, precooled to −30° C., of 11.84 mmol of 1-trityl-1H-imidazole-4-carbaldehyde [33016-47-6] in 30 ml of tetrahydrofuran is added. The mixture is stirred at −30° C. for 30 minutes, and then the reaction mixture is warmed to room temperature and quenched with saturated aqueous ammonium chloride solution. The phases are separated, and the aqueous phase is extracted with ethyl acetate (3×). The combined organic phases are washed with brine, dried with magnesium sulphate and evaporated. The title compound is obtained as a white solid from the residue by recrystallization from ethyl acetate. Rf=0.23 (CH 2 Cl 2 2M NH 3 in EtOH 97:3); Rt=7.32.
The following compounds are prepared in analogy to the process described in Example 1:
3 4-(8-Methyl-5,6-dihydro-8H-imidazol[5,1-c][1,4]oxazin-8-yl)benzonitrile
starting from 4-[1-hydroxy-1-(1-trityl-1H-imidazol-4-yl)ethyl]benzonitrile. Beige solid; Rf=0.26 (dichloromethane-2M ammonia in ethanol 97:3); Rt=4.54.
The starting material is prepared as follows:
a) 4-[1-Hydroxy-1-(1-trityl-1H-imidazol-4-yl)-ethyl]benzonitrile
12.98 mmol of methylmagnesium bromide solution (3M in diethyl ether) are added dropwise to a solution of 11.80 mmol of 4-(1-trityl-1H-imidazol-4-carbonyl)benzonitrile in 50 ml of tetrahydrofuran at −30° C. The cooling bath is removed and the mixture is stirred at room temperature for 1 hour. The reaction mixture is diluted with 100 ml of dichloromethane, and 100 ml of saturated aqueous ammonium chloride solution are added. The phases are separated and the aqueous phase is extracted with dichloromethane (1×). The combined organic phases are dried over magnesium sulphate and evaporated. The title compound is obtained without further purification as a white foam from the residue. Rf=0.15 (heptane-ethyl acetate 1:1), Rt=7.40.
b) 4-(1-Trityl-1H-imidazol-4-carbonyl)benzonitrile
A solution of 27.20 mmol of 4-[hydroxy-(1-trityl-1H-imidazol-4-yl)methyl]benzonitrile (Example 1d) in 100 ml of dichloromethane is mixed with 272.00 mmol of manganese(IV) oxide and heated to reflux for 2 hours. The reaction mixture is allowed to cool and is filtered through kieselguhr. The kieselguhr is washed with 100 ml of dichloromethane, and the combined organic phases are evaporated. The title compound is obtained without further purification as a white solid from the residue. Rf=0.13 (heptane-ethyl acetate 4:1), Rt=8.39.
5 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)-2-fluorobenzonitrile
starting from 2-fluoro-4-iodobenzonitrile [137553-42-5].
7 8-(4-Nitrophenyl)-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
starting from 1-iodo-4-nitrobenzene [636-98-6]. Tetrahydrofuran is used instead of N,N-dimethylformamide as solvent in stage c
9 8-(4-Methanesulphonylphenyl)-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
starting from 1-iodo-4-methanesulphonylbenzene [64984-08-3].
10 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-vyl)2,6-difluorobenzonitrile
starting from 2,6-difluoro-4-iodobenzonitrile [14743-50-3].
11 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)-2-methoxybenzonitrile
starting from 4-iodo-2-methoxybenzonitrile [677777-44-5].
12 8-Benzo[b]thiophen-3-yl-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
starting from 3-iodobenzo[b]thiophene [36748-88-6].
13 8-(7-Fluorobenzofuran-3-yl)-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
starting from 3-bromo-7-fluorobenzofuran [1288851-92-3].
14 8-Pyridin-4-yl-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
starting from 4-iodopyridine [15854-87-2].
15 4-(6,6-Dimethyl-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile
starting from ethyl 2-[(4-cyanophenyl)-(1-trityl-1H-imidazol-4-yl)methoxy]-2-methylpropionate.
The starting materials are prepared as follows:
a) Ethyl 2-[(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methoxy]-2-methylpropionate
4.00 mmol of lithium diisopropylamine (2M in tetrahydrofuran) are added to a solution of 4.00 mmol of ethyl 2-[(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methoxy]propionate in 40 ml of tetrahydrofuran and 5 ml of hexamethylphosphoric triamide (HMPA) at −78° C. The mixture is stirred at −78° C. for 15 minutes, and 4.00 mmol of methyl iodide are added. The reaction mixture is stirred at −78° C. for 30 minutes and warmed to room temperature over 2 hours. the reaction mixture is diluted with dichloromethane, and saturated aqueous ammonium chloride solution is added. The phases are separated and the aqueous phase is extracted with dichloromethane (1×). The combined organic phases are dried with sodium sulphate and evaporated. The title compound is identified from the residue on the basis of the Rf by flash chromatography (SiO 2 60F).
b) Ethyl 2-[(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methoxy]propionate
The title compound is prepared in analogy to Example 1c starting from ethyl 2-bromopropionate [535-11-5] and 4-[hydroxy-(1-trityl-1H-imidazol-4-yl)methyl]benzonitrile (Example 1d).
17 8-(3,4-Difluorophenyl)-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
starting from 3,4-difluoro-1-iodobenzene [64248-58-4]. White wax.
19 3-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile
starting from 3-iodobenzonitrile [69113-59-3]. Brown oil. Rf=0.20 (dichloromethane-2M ammonia in ethanol 97:3); Rt=4.12.
20 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)phthalonitrile
starting from 4-iodophthalonitrile [69518-17-8].
21 4-(8-(4-Cyanophenyl)-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile
starting from 4-[hydroxy-(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methyl]benzonitrile. Whitish solid. Rf=0.14 (dichloromethane-2M ammonia in ethanol 97:3); Rt=5.66.
The starting materials are prepared as follows:
a) 4-[Hydroxy-(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methyl]benzonitrile
4-(1-Trityl-1H-imidazol-4-carbonyl)benzonitrile (Example 3b) is reacted with 4-iodobenzo-nitrile [3058-39-7] in analogy to Example 1d. The title compound is obtained as a white solid. Rt=7.9.
23 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)naphthalene-1-carbonitrile
starting from 4-iodonaphthalene-1-carbonitrile [140456-96-8]. Yellowish solid. Rf=0.13 (dichloromethane-2M ammonia in ethanol 95:5); Rt=5.49.
The following compound is prepared in analogy to the process described in Examples 1 and 3:
22 4-(8-Phenyl-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile
starting from 4-(1-trityl-1H-imidazol-4-carbonyl)benzonitrile (Example 3b) and phenyl-magnesium bromide [100-58-3]. Whitish solid. Rf=0.23 (dichloromethane-2M ammonia in ethanol 97:3); Rt=5.84.
Example 2
4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]thiazin-8-yl)benzonitrile
The title compound is obtained as a white solid in analogy to Example 1 from ethyl [(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methylsulphanyl]acetate. Rf=0.19 (dichloromethane-2M ammonia in ethanol 97:3); Rt=4.74.
The starting materials are prepared as follows:
a) Ethyl [(4-cyanophenyl)(1-trityl-1H-imidazol-4-yl)methylsulphanyl]acetate
1.80 mmol of triphenylmethyl chloride [76-83-5] and 1.92 mmol of diisopropylethylamine are added to a solution of 1.46 mmol of ethyl [(4-cyanophenyl)(1H-imidazol-4-yl)methyl-sulphanyl]acetate in 20 ml of N,N-dimethylformamide at room temperature. The reaction mixture is stirred at room temperature for 16 hours, then poured into ice-water and extracted with ethyl acetate. The combined organic phases are washed with brine, dried with sodium sulphate and evaporated. The title compound is obtained as a white solid from the residue by flash chromatography (SiO 2 60F). Rf=0.36 (ethyl acetate-heptane 1:1); Rt=8.13.
b) Ethyl [(4-cyanophenyl)(1H-imidazol-4-yl)methylsulphanyl]acetate
A solution of 5.02 mmol of 4-[hydroxy-(1H-imidazol-4-yl)methyl]benzonitrile and 50.2 mmol of ethyl mercaptoacetate in 10 ml of trifluoroacetic acid is stirred at 70° C. for 24 hours. The reaction mixture is cooled to room temperature, poured into ice-water and neutralized with 4M sodium hydroxide solution. The mixture is extracted with ethyl acetate, and the combined organic phases are dried with sodium sulphate and evaporated. The title compound is obtained as an amber-coloured oil from the residue by flash chromatography (SiO 2 60F). Rf=0.13 (dichloromethane-2M ammonia in ethanol 97:3); Rt=5.10.
c) 4-[Hydroxy-(1H-imidazol-4-yl)-methyl]benzonitrile
36.2 mmol of 4-[hydroxy-(1-trityl-1H-imidazol-4-yl)methy]benzonitrile (Example 1d) are suspended in 100 ml of tetrahydrofuran. 7.2 ml of 6M hydrochloric acid are added to the suspension, and the reaction mixture is heated to reflux for 16 hours. The reaction mixture is cooled to room temperature and the solid is filtered off. The mother liquor is evaporated and the residue is taken up in water, basified with 4M sodium hydroxide solution and extracted with tert-butyl methyl ether. The aqueous phase is evaporated and thoroughly dried. The crude product is obtained as a beige foam which is employed without further purification for the next stage. Rt=3.3.
The following compounds are prepared in analogy to the process described in Example 2:
4 4-(8-Methyl-5,6-dihydro-8H-imidazo[5,1-c][1,4]thiazin-8-yl)-benzonitrile
starting from 1-(1-trityl-1H-imidazol-4-yl)ethanone [116795-55-2]. White solid. Rf=0.29 (dichloromethane-2M ammonia in ethanol 97:3); Rt=4.96.
6 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]thiazin-8-yl)-2-fluorobenzonitrile
starting from 2-fluoro-4-iodobenzonitrile [137553-42-5].
Example 8
8-[4-(1H-Tetrazol-5-yl)phenyl]-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
3.34 mmol of trimethylsilyl azide are added to a solution of 0.17 mmol of 4-(5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile (Example 1) and 0.017 mmol of dibutyltin oxide in 4.0 ml of toluene. The reaction mixture is heated at 125° C. overnight. It is cooled to room temperature and evaporated. The title compound is identified from the residue on the basis of the Rf by flash chromatography (SiO 2 60F).
Example 16
8-(4-Fluorophenyl)-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazine
4.33 mmol of 8-(4-fluorophenyl)-2-trityl-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-2-ium mesylate are taken up in 10 ml of glacial acetic acid, and the solution is heated at 100° C. for 16 hours. The reaction solution is cooled to room temperature and poured into ice-cold 4M sodium hydroxide solution. The mixture is extracted with dichloromethane. The combined organic phases are dried with sodium sulphate and evaporated. The title compound is obtained as a white solid from the residue by flash chromatography (SiO 2 60F) and subsequent digestion with diethyl ether. Rf=0.29 (dichloromethane-2M ammonia in ethanol 95:5); Rt=4.42.
The starting materials are prepared as follows:
a) 8-(4-Fluorophenyl)-2-trityl-5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-2-ium mesylate
The title compound is obtained in analogy to Example 1 from 4-fluoro-1-iodobenzene [352-34-1].
Example 18
1-[4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)phenyl]ethanone
3 mmol of methylmagnesium bromide solution (3M in diethyl ether) are added to a solution of 0.97 mmol of 4-(5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)-N-methoxy-N-methyl-benzamide in 10 ml of absolute tetrahydrofuran under argon. The reaction solution is stirred at room temperature for 4 hours and then poured into saturated aqueous ammonium chloride solution and extracted with tert-butyl methyl ether. The combined organic phases are dried over magnesium sulphate and evaporated. The title compound is obtained as a beige solid from the residue by flash chromatography (SiO 2 60F). Rf=0.19 (dichloromethane-2M ammonia in ethanol 97:3); Rt=4.10.
The starting materials are prepared as follows:
a) 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)-N-methoxy-N-methylbenzamide
9.30 mmol of thionyl chloride are added to a solution of 3.10 mmol of 4-(5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzoic acid in 5 ml of chloroform. The reaction mixture is heated to reflux for 3 hours and then evaporated. The residue is stripped with toluene and then taken up in 10 ml of dichloromethane. The reaction solution is cooled to 0-5° C., and 3.10 mmol of N,O-dimethylhydroxylamine hydrochloride, followed by 15.5 mmol of diisopropylethylamine, are added. The reaction mixture is stirred at room temperature for 16 hours and filtered through Hyflo, and the filtrate is evaporated. The title compound is obtained as a yellowish oil from the residue by flash chromatography (SiO 2 60F). Rf=0.13 (dichloromethane-2M ammonia in ethanol 97:3); Rt=4.00.
b) 4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzoic acid
A solution of 3.10 mmol of 4-(5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile (Example 1) in 5 ml of ethanol is mixed with 3.1 ml of 2M sodium hydroxide solution. The reaction solution is heated to reflux for 24 hours. The reaction mixture is cooled to room temperature, neutralized with 2M hydrochloric acid and evaporated. The crude product is employed without further purification for the next stage. Rt=3.79.
Example 24
4-(5,6-Dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile
The racemic compound 4-(5,6-dihydro-8H-imidazo[5,1-c][1,4]oxazin-8-yl)benzonitrile (Example 1) is fractionated into the enantiomers by chiral preparative HPLC. The title compound is isolated as the enantiomer which elutes second. Rt*=8.22.
* HPLC method:
Column: 250×50 mm CHIRALPAK® AD 20 μm
Mobile phase: CO 2 /methanol 80:20
Flow rate: 240 ml/min
Detection: UV 230 nm
Temperature: 25° C.
Pressure: 150 bar
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The application relates to novel heterocyclic compounds of the general formula (I) and salts, preferable pharmaceutically acceptable salts, thereof, in which R, R 1 , R 2 , R 3 , Q, m and n have the meanings explained in detail in the description, a process for their preparation and the use of these compounds as medicaments, in particular as aldosterone synthase inhibitors.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method and apparatus for mixing and dispensing fluids which react with each other. The mix cylinder, piston and orifices of a foam gun are flushed and cleaned at the end of each dispensing operation. The invention is particularly useful for mixing organic resins and polyisocyanates to dispense polyurethane foam. The dispensing gun may also dispense a single fluent material.
2. Description of Background and Relevant Information
The forming of synthetic foams, such as polyurethane foams, requires uniform mixing of liquid organic resins and polyisocyanates. A problem that occurs in such mixing is that the organic resin and polyisocyanate react relatively rapidly and accumulate over the surfaces of the dispensing apparatus. The foam increases in volume and may block passages within the foam gun and the feed hoses leading to the gun. This disables the foam gun, which must then be replaced, leading to down-time and excessive cost.
U.S. Pat. No. 4,426,023 to SPERRY et al. discloses a foam gun in which a cleaning assembly supplies a solvent to the discharge part of the foam gun and a valving rod of a piston travels through a solvent reservoir. This cleaning assembly cleans the discharge port and the valving rod but does not adequately clean the orifices through which the organic resins and polyisocyanates are supplied.
U.S. Pat. No. 4,159,079 to PHILLIPS, Jr. discloses a foam dispenser which includes gaskets to prevent the emigration of liquids from the mixing chamber. The mixing chamber is press fit inside the bore of the front section of the foam gun. The valving rod is bathed in a cleaning and/or lubricating solvent in a chamber.
U.S. Pat. No. 4,568,003 to SPERRY et al. discloses a foam dispenser in which the mixing chamber is detachable to facilitate cleaning.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a foam gun in which a cleaning assembly circulates solvent to clean and flush the orifices and the interior of the cylinder without depending on interference fits in the sealing system.
This object is obtained by providing a dispensing gun for mixing and dispensing a plurality of reactable fluids having a housing including a first bore, which has an inner opening, a discharge opening, and a plurality of passages for supplying the reactable fluids. A mixing cylinder includes an inner opening, a discharge opening, and a plurality of fluid supplying orifices and is slidable in the first bore. A piston rod is movable through the inner opening of the first bore and the inner opening of the mixing cylinder towards and away from the discharge openings, whereby the mixing cylinder moves away from the discharge opening of the first bore in response to the movement of the piston rod away from the discharge openings, so that the plurality of passages for supplying the reactable fluids becomes aligned with the plurality of fluid supplying orifices to dispense the reactable fluids from the discharge openings.
According to another aspect of the invention, the housing includes a second bore which communicates with the inner opening of the first bore, and biasing means within the second bore for biasing the mixing cylinder towards the discharge opening of the first bore. The piston rod engages the mixing cylinder to move the mixing cylinder away from the discharge opening of the first bore. The mixing cylinder includes a restriction and the piston rod includes a shoulder. The shoulder engages the restriction to move the mixing cylinder away from the discharge opening of the first bore.
According to another aspect of the invention, the housing includes a third bore, which includes means for moving the piston rod. The means for moving the piston rod may be an air cylinder shaft connected to the piston rod, the air cylinder shaft being moved by compressed air. A trigger actuates the movement of the air cylinder shaft. The third bore includes an open end opening towards the first bore and the air cylinder shaft extends through the opening and is connected to the piston rod. A front air cylinder head seals the open end and the air cylinder shaft is slidable through the front air cylinder head.
According to still another aspect of the invention, the dispensing gun includes means for cleaning the mixing cylinder, which includes means for supplying cleaning solvent. At least one port in the housing communicates with a space between the inner surface of the first bore and the outer surface of the mixing cylinder. A source of cleaning solvent supplies cleaning solvent to a first port in the housing and a second port returns cleaning solvent to the source.
According to another aspect of the invention, sealing means are provided adjacent the plurality of fluid supplying orifices. The sealing means contacts the mixing cylinder and includes at least two seals. A pusher respectively pushes each seal against the mixing cylinder. An O-ring is provided between each seal and pusher, and a bolt contacts the pusher to adjust the force of the seal against the mixing cylinder.
The dispensing device may dispense a single fluid, and includes a housing including a first bore, which has an inner opening, a discharge opening, and a passage for supplying fluid. A cylinder has an inner opening, a discharge opening, and a fluid supplying orifice and is slidable in the first bore. A piston rod is movable through the inner opening of the first bore and the inner opening of the cylinder towards and away from the discharge openings, whereby the cylinder moves away from the discharge openings of the first bore in response to the movement of the piston rod away from the discharge openings, so that the passage for supplying fluid becomes aligned with the fluid supplying orifice to dispense the fluid from the discharge openings.
The housing includes a second bore which communicates with the inner opening of the first bore, and biasing means within the second bore for biasing the cylinder towards the discharge opening of the first bore. The piston rod engages the cylinder to move the cylinder away from the discharge opening of the first bore. The cylinder includes a restriction and the piston rod includes a shoulder, the shoulder engaging the restriction to move the cylinder away from the discharge opening of the first bore. The housing includes a third bore, which includes means for moving the piston rod.
According to another aspect of the invention, the dispensing device includes means for cleaning having means for supplying cleaning solvent to at least one port in the housing. A space exists between the inner surface of the first bore and the cylinder, and the port has one end communicating with the space. A source of cleaning solvent supplies cleaning solvent to a first port in the housing and a second port returns cleaning solvent to the source.
The dispensing device includes a housing including a first bore, having an interior surface, an inner opening, a discharge opening, and at least one passage for supplying fluid, a cylinder having an outer surface, an inner opening, a discharge opening, and at least one fluid supplying orifice, the cylinder being mounted in the first bore so that a space exists between the inner surface of the first bore and the outer surface of the cylinder, a piston rod being movable through the inner opening of the first bore and the inner opening of the cylinder towards and away from the discharge openings to allow fluent material to be dispensed from the discharge openings when the piston rod moves away from the discharge openings and uncovers the at least one fluid supplying orifice, and means for supplying cleaning solvent to the space between the inner surface of the first bore and the outer surface of the cylinder, so that when the piston rod moves towards the discharge openings, cleaning solvent is drawn through the at least one fluid supplying orifice to clean the orifice and the interior of the cylinder.
The means for supplying cleaning solvent includes at least one port in the housing, and more particularly a source of cleaning solvent, a first port for supplying cleaning solvent to the housing, and a second port for returning cleaning solvent to the source. It further comprises an O-ring on the piston rod to wipe the interior of the cylinder. A second bore communicates with the inner opening of the first bore and the means for supplying cleaning solvent supplies cleaning solvent to the second bore.
Another aspect of the invention is directed to a method of dispensing fluent material from a dispensing device including a bore having a discharge opening and at least one passage for supplying fluent material, a cylinder having a discharge opening and at least one fluid supplying orifice and being slidable within the first bore, and a piston rod being slidable within the cylinder where the method includes the steps of sliding the piston rod in a direction away from the discharge openings and engaging the cylinder by the piston rod to move the cylinder in a direction away from the discharge opening of the bore so that the at least one passage and the at least one fluid supplying orifice are aligned to allow the fluent material to flow from the at least one passage through the at least one fluid supplying orifice to be dispensed through the discharge openings.
The method further includes bissing the cylinder towards the discharge opening of the bore.
The method of dispensing fluent material can also include supplying at least two fluent materials to the cylinder, and dispensing the mixture of the fluent materials through the discharge openings.
Cleaning solvent is supplied to clean the at least one fluid supplying orifice and the cylinder by moving the piston rod in a direction towards the discharge opening of the bore to draw cleaning solvent through the at least one fluid supplying orifice. The cleaning solvent may be continuously supplied.
The method of cleaning a dispensing device having a housing including a bore having a discharge opening and at least one passage for supplying fluent material, a cylinder having a discharge opening and at least one fluid supplying orifice and being mounted in the bore so that a space exists between the inner surface of the bore and the outer surface of the cylinder, and a piston rod being slidable within the cylinder, includes the steps of supplying cleaning solvent to the space between the inner surface of the bore and the cylinder; and sliding the piston rod towards the discharge openings to draw cleaning solvent through the at least one fluid supplying orifices and the interior of the cylinder. The cleaning solvent is supplied to the space through at least one port in the housing. More particularly, the cleaning solvent is supplied from a source to a first port in the housing and returned to the source from a second port in the housing. The cleaning solvent is continuously supplied to the space. The method of cleaning a dispensing device further includes wiping the interior of the cylinder by an element attached to the piston rod. The element may be an O-ring attached to the piston rod.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is further explained in the description which follows with reference to the drawings illustrating, by way of a non-limiting example, an embodiment of the invention wherein:
FIG. 1 is a cross-sectional view of the foam gun;
FIG. 2 is an enlarged cross-sectional view of the foam gun, taken along line II--II of FIG. 3;
FIG. 3 is a cross-sectional view of the housing, taken along line III--III of FIG. 2;
FIG. 4 is a detailed view showing the relationship between the mix cylinder, the piston rod and the return spring;
FIG. 5 is a view of the piston rod;
FIG. 6 is a view of the mix cylinder;
FIG. 7 is a perspective view of the foam gun;
FIG. 8 is a side view of the foam gun; and
FIG. 9 is a top view of the foam gun.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIGS. 1 and 2, the foam gun of the present invention includes a housing 10, which includes a nose portion 12 connected to an air cylinder portion 14 by screws or like fasteners connected through holes 16 and 18 in the nose portion and air cylinder portion, respectively. This allows the housing portions to be easily assembled and disassembled for maintenance and cleaning.
Nose portion 12 includes a first bore 20 which includes an inner end 22 and a discharge end 24. Mixing cylinder 26 is slidable within first bore 20. The mixing cylinder includes outer surface 28, inner surface 30, inner end 32, and discharge end 34 (see FIG. 6). A restriction 36 is formed in the interior of mixing cylinder 26 and an abutment surface 38 is formed at inner end 32. Spaced reactant fluid supplying orifices 40 and 42 extend through the inner and outer surfaces of mixing cylinder 26. An O-ring 45 seals mixing cylinder 26 with respect to first bore 20.
Referring particularly to FIGS. 2, 4, and 5, piston rod 44 slides within mixing cylinder 26. Piston rod 44 includes shoulder 46 for engagement with restriction 36 of mixing cylinder 26, as will be described in detail below. O-ring 48 fits in groove 50 to seal the piston rod with respect to mixing cylinder 26.
As shown in FIGS. 1 and 2, nose portion 12 includes second bore 52 having an abutment wall 53 at one end whose other end communicates with first bore 20 at inner end 22. Return spring 54 is mounted within second bore 52 and abuts against abutment wall 53 at one end and abutment surface 38 of mixing cylinder 26 at the other end.
Air cylinder portion 14 includes third bore 56 which communicates with second bore 52 through passage 58. Third bore 56 includes rear cylinder head 60 to seal the outer end of third bore 56. Rear cylinder head 60 is held between snap ring 62 and a shoulder 64 at the rear end of third bore 56. O-ring 66 is also secured to rear cylinder head 60.
Air cylinder piston 68 includes O-ring 70 and is slidable within third bore 56. Air cylinder shaft 72 is connected to air cylinder piston 68 by fastener 74, which may be a socket head bolt or the like. Front air cylinder head 76 is held within passage 58 by snap ring 80 and shoulder 82. Air cylinder head O-ring 78 seals front air cylinder head 76 with respect to passage 58. Air cylinder shaft O-ring 84 is associated with front air cylinder head 76. Air cylinder shaft 72 extends through and is slidable relative to front air cylinder head 76 and is sealed with respect thereto by O-ring 84. Air cylinder shaft 72 is connected to piston rod 44 by snap ring connector 86.
Air supply passages 88 and air return passage 90 extend through air cylinder portion 14 into third bore 56. Compressed air is supplied to air supply passages 88 through air supply port 92 (see FIG. 8) from a compressed air supply source (not shown) in a conventional manner. Trigger 94 is actuated to direct compressed air through air supply passages 88 in a known manner to move air cylinder piston 68 to the right as seen in FIG. 1. The foam gun also includes handle 96 and trigger guard 98.
The foam gun includes a pair of inlet terminals 100, 102 which supply reactable fluids to mixing cylinder 26. Inlet hoses (not shown) from fluid sources are connected to the inlet terminals as is known in the art. The reactable fluids may be organic resins and polyisocyanates which react with each other to form polyurethane foam. Inlet terminals 100 and 102 lead to respective inlet passages 110a, 112a which open to first bore 20.
As illustrated in FIGS. 2 and 3, sealing arrangement 104 is located in nose portion 12 adjacent the inlet passages. The sealing arrangement 104 includes a pair of radially extending unaligned bores 106 and 108. A pair of seals 110 and 112 are located within respective bores and contact mixing cylinder 26. A pair of pushers 114 and 116 apply force against each seal through respective compression rings 118 and 120. Threaded plugs 122 and 124 are inserted into the respective bores to adjustably apply a force to the respective pushers. Holes 110', 112' are located in seals 110 and 112, respectively, and communicate with inlet passages 110a, 112a, respectively.
An arrangement is also provided for supplying cleaning solvent to nose portion 12 to clean piston rod 44, mixing cylinder 26, orifices 40, 42, first bore 20, and second bore 52. Supply and return ports 126 and 128 (see FIGS. 7 and 9) are connected to the top of nose portion 12 to supply and circulate a cleaning solvent from a source (not shown). A pump may be used to apply pressure to continuously circulate the cleaning solvent throughout the nose portion.
As can be seen in FIG. 2, there is a gap or space between outer surface 28 of mixing cylinder 26 and the inner surface of first bore 20. Cleaning solvent flows through the supply port, the gap, the orifices and the second bore as will be described below.
The operation of the foam gun of the present invention will now be described with particular reference to FIGS. 2 and 4. When the trigger is pulled, compressed air flows through air supply passages 88 to move air cylinder piston 68 to the left. Since piston rod 44 is connected to air cylinder shaft 72, piston rod 44 also moves to the left within mixing cylinder 26 as seen in FIG. 2. At the end of the travel of piston rod 44 in mixing cylinder 26, shoulder 46 engages restriction 36 and pulls the mixing cylinder to the left against the force of return spring 54, allowing alignment of orifices 40 and 42 with the holes 110', 112' in the seals 110, 112, respectively, and consequently alignment with the inlet passages 110a, 112a for the reactable fluids. The fluids react in the mixing cylinder and polyurethane foam is dispensed from discharge end 24.
When pressure is relieved from the trigger, air flows through passage 90, forcing air cylinder piston 68 and piston rod 44 to the right. At the same time, return spring 54 forces mixing cylinder 26 to the right to bring the orifices 40 and 42 out of alignment with the inlet passages 110a, 112a to shut off flow of the reactable fluids to the mixing cylinder.
As described above, the cleaning solvent continuously circulates within nose portion 12 of the housing. As piston rod 44 moves to the right, O-ring 48 wipes the inner surface of the mixing cylinder and creates a vacuum to pull cleaning solvent from the space between the mixing cylinder and the inner surface of the first bore through orifices 40 and 42 into the mixing cylinder to thereby flush and clean the orifices and the inner surfaces of the mixing cylinder.
The housing may be machined from aluminum bar stock and the mixing cylinder, piston rod, and cylinder shaft may be steel. The seals may be made from "Teflon".
As can be seen, the present invention does not depend on interference fits for the sealing system. The housing is easily assembled and disassembled and the cleaning system cleans and flushes the mixing cylinder and orifices each time the trigger is released.
Although the invention has been described with reference to particular means, materials and embodiments, it is to be understood that the invention is not limited to the particulars disclosed and extends to all equivalents within the scope of the claims.
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Dispensing gun for mixing and dispensing reactable fluent materials. A cylinder is slidable within a bore in response to a piston sliding within the cylinder. When the cylinder moves away from a discharge opening, orifices in the wall of the cylinder become aligned with supply passages in the bore allowing the reactable fluent materials to mix in the cylinder and be dispensed from the discharge opening. The cylinder, piston and orifices are cleaned by a cleaning solvent at the end of each dispensing operation. Movement of the piston towards the discharge opening draws the cleaning solvent through the orifices into the interior of the cylinder. The dispensing gun is particularly useful for mixing organic resins and polyisocyanates to dispense polyurethane foam.
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BACKGROUND OF THE INVENTION
The present invention relates to a method of treating a high hydrohead fibrous porous web material and, for example, to a method that increases the retentive water absorbency of the web. The retentive water acquision rate may also be increased. As used herein the term "absorbency" generally refers to the ability of a material to acquire a fluid and the acquision rate refers to the rate of such acquision. An example of a use where high absorbency and high acquision are desired would be wiper type materials. In addition to having the characteristics of high absorbency and high acquision rate, wipers desirably also should have the characteristics of high retentive absorbency and high retentive acquision rate. The term retentive acquision rate is used herein to designate comparison of the rate of acquision of a fluid by a material when the material is first used to acquire the fluid as compared to the second, third and fourth times the material is used to acquire the fluid. Improved retentive acquisition rate is evidenced by by smaller decreases in the rate of acquisition with multiple uses. Likewise, the term retentive absorbency is used to designate comparison of the amount of fluid acquired by a material when the material is first used to acquire the fluid as compared to the amount of fluid acquired when the material is used a second, third, fourth time to acquire the fluid. Improved retentive absorbency is evidenced by smaller decreases in the amount of fluid absorbed by the material with multiple uses. In other words, the ability of the material to reabsorb fluid after having, in our test, been exposed to fluid, wrung out and allowed to dry.
In the copending, concurrently filed application Ser. No. 07/608,103 of Bernard Cohen and Michael T. Morman entitled Low Hydrohead Fibrous Porous Web with Improved Retentive Wettability the inventors disclose that the application of corona discharge treatment to low hydrohead webs whose surface includes a surface active agent having a hydrophile-lipophile balance of 6 or greater results in a significant increase in the retentive wettability, as defined therein, of such webs. This application is hereby incorporated by reference. Low hydrohead webs of that type would generally be unsatisfactory for use as a wiper material due to their open pore structure which would greatly reduce the ability of the web to acquire fluids. Conversely, high hydrohead webs, as defined herein, would generally be undesirable for use in applications where rapid transmission of large amounts of fluid through the material is desired. This undesirability arises from the generally tight, closed pore structure of high hydrohead materials. Such pore structure would inhibit the passage of fluids therethrough in rapid fashion.
In the past, hydrophobic wipers have been subjected to treatment with surfactants to improve their characteristics. The wipers have been treated with surfactant by (1) passing the formed wiper through a bath containing the surfactant in either neat or solution form and drying the wiper as needed so that a given amount of the surfactant is deposited on the wiper, or (2) spraying a surfactant in either neat or solution form on the fibers as they are being formed or on the fibrous porous web and drying the wiper as needed so that a given amount of the surfactant is deposited on the wiper, or, (3) adding surfactant to a thermoplastic resin prior to extrusion and formation of the resin into a thermoplastic porous web material. In the later situation, under known process conditions, the added surfactant exudes or migrates to the surface of the fibres of the porous web material during or shortly after fiber formation. This phenomenon has been referred to as "blooming" the surfactant. It is believed that blooming results from the insolubility of the surfactant in the thermoplastic polymer as the polymer cools. See U.S. Pat. No. 4,535,020 to Thomas et al (hereafter Thomas et al 020) which demonstrates surfactant blooming in a diaper liner formed from a perforated film.
A wiper made from a hydrophobic material, such as a thermoplastic polymer, will not readily acquire or absorb spilled fluids because the surface tension of the fluid is greater than the critical surface energy of the hydrophobic material. Surface tension is the contractile surface force of a fluid where the fluid tries to assume a spherical form and to present the least possible surface area. It is usually measured in dynes per centimeter. Accordingly, because of its effect on the insulating fluids, surfactant has been previously applied to wipers. Application of a surfactant onto a wiper material may make a nonabsorbing wiper absorbent by at least two mechanisms: (1) Surfactants present on the wiper can dissolve into a fluid and lower the surface tension of the resulting solution to more equal the critical surface energy of the wiper material. Accordingly, when a surfactant coated wiper is used to wipe up a fluid such as water, the surfactant acts to lower the surface tension of the fluid and allow the fluid to be acquired at a faster rate and for a larger amount of fluid to be absorbed into the wiper. In this situation, a certain amount of the surfactant on the wiper is lost with each wiping and wringing and unacceptable acquision rate and absorbency occurs at some following wiping due to the lack of availability of surfactant to lower the surface tension of the fluid. (2) The surfactant can be coated onto the fibers making up the wiper, making the fiber surface of the wiper more hydrophilic, i.e., increase the apparent critical surface energy of the fibers. In this situation the wiper would have permanent absorbency if the surfactant did not dissolve in the fluid the wiper was used to pick up.
As any anyone will testify, it is an aggravating event when a disposable wiper fails in its appointed task of rapidly acquiring and absorbing a fluid spill.
Accordingly, it has been a goal of those in the art to provide a high hydrohead porous web wiper material which has an improved acquision rate and absorbency. This was the initial goal because, if the material cannot acquire and absorb fluid at all, the material cannot function as a wiper. Additionally, it has been a goal of those in the art to provide a high hydrohead porous web wiper material which has an improved retentive acquision rate and improved retentive absorbency. That is, when dried and wrung-out between wipings, the wiper has a significant increase in the number of times it can be used to absorb fluid. This goal is desirable not only from the standpoint of allowing a given disposable wiper to be used more times but also from an environmental standpoint in that fewer wipers will be disposed into the environment.
Corona discharge treatment of films is old in the art and it is known that corona discharge treatment of a polymer film in the presence of air entails substantial morphological and chemical modifications in the polymer film's surface region. See Catoire et al, "Physico-chemical modifications of superficial regions of low-density polyethylene (LDPE) film under corona discharge," Polymer, vol. 25, p. 766, et. seq, June, 1984.
Generally speaking, corona treatment has been utilized to either (1) improve the print fastness on the film, or (2) to perforate the film. For example, U.S. Pat. No. 4,283,291 to Lowther describes an apparatus for providing a corona discharge, and U.S. Pat. No. 3,880,966 to Zimmerman et al discloses a method of using a corona discharge to perforate a crystalline elastic polymer film and thus increase its permeability. U.S. Pat. No. 3,471,597 to Schirmer also discloses a method for perforating a film by corona discharge. U.S. Pat. No. 3,754,117 to Walter discloses an apparatus and method for corona discharge treatment for modifying the surface properties of thin layers of fibers which improve the adhesion of subsequently applied inks or paints or of subsequent bonding.
It also is possible to treat a diaper liner material with a corona discharge and then immediately dip the film in a surfactant solution. Because the corona effect on the material generally starts to immediately decay, it is important to get the corona treated material into the bath as quickly as possible. Such a method is discussed in Japanese KOKAI Patent Number SHO63[1988]-211375. This document discloses a method for producing a nonwoven fabric having a long lasting hydrophilicity. The method involves first treating a nonwoven fabric of synthetic fiber by a corona discharge and then coating the treated fabric with about 2-10 grams per square meter of fabric of surface active agent.
Of particular interest is the fact that Thomas et al 020 is directed to the utilization of corona discharge in conjunction with surfactant treated films to effect improved wettability, i.e. higher fluid transmission rates and therefore decreased run-off of fluid. In this regard Thomas et al 020 states that a perforated film which has been treated with surfactant and which is then corona discharge treated results in a film with very low, zero or near zero fluid run-off on the first run-off test. Thomas et al 020 reports that this effect is accomplished because the corona discharge treatment acts on the chemical additive, the surfactant, to provide the perforated film with a zero or near zero percent run off. Thomas et al 020 postulates that this effect is achieved due to the surfactant providing a greater polarizability to the film then the film would have without the surfactant being added. The corona discharge treatment provides additional polarizing effect and, in combination with the surfactant, provides improved wettability. Because Thomas et al 020 is directed toward use of the perforated film as a diaper liner, it does not appear to address the questions of acquision rate and absorbency. Acquision rate, as defined herein, usually does not apply to a film and diaper liners are generally designed to be permeable to fluids as opposed to absorbing them. Lastly, Thomas et al 020 does not appear to address retentive capabilities at all because the testing reported therein is directed to one-time exposure to fluid.
In view of the forgoing, and the discovery by Messers, Cohen and Morman that treating a low hydrohead porous web with a surface active agent having a hydrophile-lipophile balance of about 6 or greater followed by corona discharge treatment yielded significantly improved retentive wettability values for the material, we decided to determine if such treatment had advantageous effects on the retentive water acquision rate and retentive water absorbency of high hydrohead porous webs. If such was the case an improved wiper would result.
SUMMARY OF THE INVENTION
In response to the above, we have devised a method of treating a high hydrohead fibrous porous web material to increase the web's retentive water acquision rate (averaged normalized rate of water absorption in subsequent reabsorptions as compared to the initial absorption rate) and retentive water absorbency (average normalized amount of water absorbed in subsequent reabsorptions as compared to the amount initially absorbed). The method generally includes the steps of: (1) providing a high hydrohead fibrous porous web having a surface concentration of at least about 0.05 percent, by weight of the web, of a surface active agent having a hydrophile-lipophile balance of at least about 6; and (2) applying a corona discharge equivalent to a charge of at least about 0.8 watt minute per square foot per side of the web to the surface active agent bearing web. The resultant web will have a percent decrease in the averaged normalized water absorbed, at two minutes, of less than about 50 weight percent in each of the second, third and fourth times the material is tested in accordance with absorbency test A when compared to the averaged normalized water absorbed upon being initially tested in accordance with absorbency test A. In some embodiments, the web will have an average absorbency decrease, as defined above, of less than about 25 percent.
In some embodiments the resultant web will have a percent decrease in the averaged normalized water absorbed, at one minute, of less than about 50 weight percent in each of the second, third and fourth times the material is tested in accordance with absorbency test A when compared to the averaged normalized water absorbed upon being initially tested in accordance with absorbency test A. Additionally, in some embodiments, the resultant web will have a percent decrease in the averaged normalized water absorbed, at one minute, of less than about 25 weight percent in each of the second, third and fourth times the material is tested in accordance with absorbency test A when compared to the averaged normalized water absorbed upon being initially tested in accordance with absorbency test A.
The treated webs generally also have improved retentive averaged normalized rates of water absorption. Thus, generally, the resulting webs have a percent decrease in the averaged normalized rate of water absorbed, in the first 2.4 seconds of absorption, of less than about 50 percent in each of the second, third and fourth times the material is tested in accordance with absorbency test A when compared to the averaged normalized rate of water absorbed upon being initially tested in accordance with absorbency test A. For example, the webs may have such improved retentive averaged normalized rates of water absorption that the averaged normalized rate of water absorbed, in the first 2.4 seconds of absorption, decreases less than about 25 percent in each of the second, third and fourth times the material is tested in accordance with absorbency test A when compared to the averaged normalized rate of water absorbed upon being initially tested in accordance with absorbency test A. Even more particularly, the webs may have such improved retentive averaged normalized rates of water absorption that the averaged normalized rate of water absorbed, in the first 2.4 seconds of absorption, decreases less than about 10 percent in each of the second, third and fourth times the material is tested in accordance with absorbency test A when compared to the averaged normalized rate of water absorbed upon being initially tested in accordance with absorbency test A.
From about 0.05% to about 3%, by weight of the web material, of surface active agent may be adhered to the web material. For example, from about 0.1% to about 1%, by weight of the web material, of surface active agent may be adhered to the web material. More particularly, from about 0.1% to about 0.4%, by weight of the web material, of surface active agent may be adhered to the web material. Even more particularly, from about 0.2% to about 0.3%, by weight of the web material, of surface active agent may be adhered to the web material.
The equivalent of from about 0.8 to about 15 watt minute per square foot per side of the web material of corona discharge may be applied to the web material. For example, the equivalent of from about 1 to about 10 watt minute per square foot per side of the web material of corona discharge is applied to the web material. More particularly, the equivalent of from about 2 to about 8 watt minute per square foot per side of the web material of corona discharge is applied to the web material.
In one embodiment our process includes the steps of (1) forming a melt from a thermoplastic fiber forming material; (2) adding, to the melt, an amount of surface active agent having a hydrophile-lipophile balance of at least about 6 sufficient to effect a surface concentration of the surface active agent of at least about 0.05%, by weight of the resulting fibrous porous web material; (3) forming the melt into fibers and the fibers into a high hydrohead fibrous process web under conditions which allow at least 0.05%, by weight of the fibrous porous web, of the surface active agent to bloom to the surface of the fibers of the porous web; and (4) applying a corona discharge equivalent to a charge of at least about 0.8 watt minute per square foot of the porous web to the surface active agent bearing web material.
Because not all of the surface active agent added to the melt blooms, the amount of surface active agent added to the melt is generally greater than the amount desired to be present on the surface. Accordingly, the amount of surface active agent added to the melt may vary with the surface active agent used, the thermoplastic material used to form the web and/or the process conditions of forming the web.
As is the case generally, in this embodiment the equivalent of from about 0.8 to about 15 watt minute per square foot of the web material of corona discharge may be applied to the web material. For example, the equivalent of from about 1 to about 5 watt minute per square foot of the web material of corona discharge is applied to the web material. More particularly, the equivalent of from about 2 to about 4 watt minute per square foot of the web material of corona discharge is applied to the web material.
In all embodiments the surface active agent may be selected from the group including one or more wetting agents, emulsions and dispersants.
In all embodiments the hydrophile-lipophile balance of the surface active agent will be about 6 or greater. For example the hydrophile-lipophile balance may range from 6 to about 20. More particularly, the hydrophile-lipophile balance of the surface active agent may range from 8 to about 20. Even more particularly, the hydrophile-lipophile balance of the surface active agent may range from 10 to about 20.
The present invention is also directed to products prepared by or preparable by our process. That is, the invention is generally directed to a fibrous porous web which has a high hydrohead when tested in accordance with Test A prior to surfactant and corona treatment in accordance with our invention and which has improved retentive averaged normalized absorbency and improved retentive averaged normalized water acquision rates after surfactant and corona treatment.
The fibrous porous web material may include a polyolefin or a blend of polyolefins or any other suitable material which may be formed into a fibrous porous web. For example, the fibrous porous web may be formed from polyethylene or polypropylene.
The fibrous porous web material may be formed by any of the wide variety of processes which provide a high hydrohead fibrous porous web. For example, the fibrous porous web may be formed by meltblowing so that the fibrous porous web includes meltblown fibers.
OBJECTS OF THE INVENTION
Accordingly, it is a general object of the present invention to provide a method whereby the retentive averaged normalized water absorbency of high hydrohead porous webs is improved.
Another general object of the present invention is to provide a high hydrohead fibrous porous web material having an increased retentive averaged normalized rate of water acquision.
Still further objects and the broad scope of applicability of the present invention will become apparent to those of skill in the art from the details given hereinafter. However, it should be understood that the detailed description of the presently preferred embodiments of the present invention is given only by way of illustration because various changes and modifications well within the spirit and scope of the invention will become apparent to those of skill in the art in view of the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of one process for carrying out the present invention.
FIG. 2 is a schematic representation of a second process for carrying out the present invention.
DEFINITIONS AND TESTS
As used herein the term "high hydrophile-lipophile balance" refers to a surface active agent having a hydrophile-lipophile balance of about six (6) or greater.
As used herein the term "surface active agent" refers to any compound that reduces surface tension when dissolved in water or water solutions or which reduces interfacial tension between two liquids, or between a liquid and a solid. There are three general categories of surface active agents: detergents, wetting agents (i.e. surfactants) and emulsifiers.
The term "hydrophile-lipophile balance" (HLB) is well known to those in the art. The HLB of a nonionic surfactant is the approximate weight percent of ethylene oxide in the surfactant divided by 5. The numerical scale of HLB values ranges from 1 (completely lipophilic or oil-loving) to 20 (completely hydrophilic or water-loving). Refer to W. C. Griffin, J. Soc. Cosmetic Chemists 317-326 (1949). In some instances the HLB of a material is determined by comparing its activity to known materials having known HLB's.
As used herein the term "high hydrohead material" refers to a porous web material which supports more than about 25 centimeters of water when its hydrohead is measured in accordance with Method 5514--Federal Test Methods Standard No. 191A. In all cases the hydrohead of the porous web material is determined by measurement either before the web has been treated with surface active agent and corona discharge as is required by the present invention or, if such is not possible, after extraction of the surface active agent from the web.
As used herein the term "water absorbency" refers to the amount, in grams, of water that a three inch by eight inch sample (folded as described in Test A, below) of high hydrohead porous web material can vertically acquire within a given amount of time.
As used herein the term "normalized water absorbency" refers to the calculated amount, in grams, of water per gram of web that a one gram sample of high hydrohead porous web material can vertically acquire within a given amount of time. This value is calculated by multiplying the "water absorbency" value for a given time period of (1/the weight of the sample).
As used herein the term "averaged normalized water absorbency" refers to the average of thee "normalized water absorbency" replicates of the material treated in accordance with out invention. In the example, the "averaged normalized water absorbency" value of the non-corona treated material was attained by averaging four replicates.
As used herein the term "rate of water absorbed" (rate) refers to the rate, in grams per second, of vertical water acquision of a three inch by eight inch sample (folded as described in Test A, below) of high hydrohead porous web material within a given amount of time.
As used herein the term "normalized rate of water absorbency" refers to the calculated rate, in reciprocal seconds, that a one gram sample of high hydrohead porous web material can vertically acquire within a given amount of time. This value is calculated by multiplying the "rate of water absorbed" (rate) value for a given time period by (1/the weight of the sample, in grams).
As used herein the term "averaged normalized rate of water absorbed" refers to the average of three "normalized rate of water absorbed" replicates of the material treated in accordance with our invention. In the example, the "averaged normalized rate of water absorbed" value of the non-corona treated material was attained by averaging four replicates.
All absorbency and rate of acquision data given herein were obtained through the use of Water Absorbency Test A, hereinafter Test A. The purpose of absorbency Test A is to quantitatively measure the absorbency and rate of acquision properties of a porous fibrous web such as a nonwoven web.
Test A requires the following materials/equipment: (1) samples of materials to be tested cut in 3 inch by 8 inch size; (2) staples; (3) distilled water; (4) one 250 ml. beaker; (5) one small lab jack; (6) an Instron model 1122 with strip recorder; (7) a Lab Wringer, a #LW838 Atlas Electric Devices Co. of Chicago, Ill., was used by us; (8) one 500 gram load cell for the Instron nd (9) one standard ten gram weight.
Sample preparation for Test A is as follows: (1) 3 inch by 8 inch samples of the material to be tested are obtained; (2) the sample is folded in on itself lengthwise one inch from one side; (3) the sample is folded in on itself lengthwise one inch from the other side to produce a three ply 1 inch by 8 inch sample; (4) the sample is folded widthwise in half; and (5) the sample is stapled one-eigth of an inch from the widthwise fold. The resultant sample is a butterfly configuration with each "wing" having three plies of sample material.
In order to conduct Test A, the Instron must first be prepared. This is done by installing the 500 gram load cell in the Instron and calibrating the machine with the 10 gram weight. The strip recorder should read 0 to 10 rams (1 inch per gram). Next the lower jaws are removed from the Instron and replaced with a lab jack. The beaker which is filled with distilled water is placed on the lab jack. The side of the beaker is marked to record the height of the water in the beaker. It is important that this level be maintained at as constant a level as possible.
Placement of a sample in the Instron should be consistent and is accomplished as follows: (1) a start-up sample is placed in the upper jaws of the Instron with the stapled end down; (2) the lab jack is used to raise the beaker so that the level of the water will be one-eighth inch above the stable (the folded edge of the sample will be one-fourth inch below the surface of the water); and (3) the height of the jack is recorded. It is important that the beaker be raised to the same height for each test.
Sample testing is accomplished as follows: (1) a sample to be tested is placed in the jaws of the Instron as stated above; (2) the strip recorder of the Instron is started and allowed to run for ten seconds to obtain a reading of the sample weight; (3) the level of fluid in the beaker is checked to ensure that it is at the mark that has been placed on the beaker; (4) the lab jack is used to raise the sample to the same height as was recorded with the start-up sample [this step should be done quickly and smoothly to minimize irregularities in the climbing portion of the curve]; (5) the test is allowed to proceed for three minutes: a chart speed of 5 inches per minute was used in all cases; (6) once the three minutes has elapsed, the recorder is turned off, the lab jack is used to lower the beaker and the sample is removed from the jaws of the Instron; (7) the staple is carefully removed from the sample but the sample is maintained in its six-ply configuration; (8) a lab wringer is used to remove excess water from the sample; [30 pounds added to the wringer arm is adequate] (9) after the sample is put through the wringer, it is unfolded and allowed to dry [5 hours is ample for a 2 ounce per square yard meltblown sample].
The data obtained in test A are as follows: (1) total sample weight is the value read from the baseline of the Instron recorder plot. [The scale of the paper in these tests was 1 inch per gram with a zero to ten gram range.]; (2) actual sample weight is the value calculated to be the total sample weight minus the weight of the staple used to hold the sample fold intact; (3) the water absorbed value is read as the gram weight absorbed amount recorded at 1.2 seconds, 2.4 seconds, 1 minute and 2 minutes of elapsed time. Early points are used to calculate acquision rate; later points are used to compare overall absorption capacity. Total water absorbed is calculated to be the difference between the baseline total sample weight and the weight read from the curve for a given time. [Note: If the weight on the curve is less than the baseline weight, the amount of water absorbed is recorded as zero. This occurs as the result of a buoyant effect as the acquision rate decreases.] (4) the rate is the value of the slope of the climbing portion of the curve and is calculated by linear regression using water absorbed readings for early points, i.e. "the points (0 sec., 0 grams), (1.2 sec., Y 1 grams) and (2.4 sec., Y 2 grams). Note that Y 1 =water weight at 1.2 seconds (weight absorbed at 1.2 seconds minus total sample weight) and Y 2 =water weight at 2.4 seconds (weight absorbed at 2.4 seconds minus total sample weight).
All data have also been normalized and given in terms of grams of water absorbed per gram of tested material. Actual sample weight were used in these calculations.
As used herein the term "decrease in averaged normalized rate" reefers to the percentage decrease in the rate of water absorption of a given sample in its second, third, and fourth times of testing, in accordance with Test A, as compared to the rate of water absorption calculated in its first time of testing when done in accordance with test A. Any increase in the rate is reported as a zero decrease.
As used herein the term "decrease in averaged normalized water absorbed" refers to the percentage decrease in the amount of water absorbed by a given sample in its second, third, and fourth times of testing, in accordance with Test A, as compared to the amount of water absorption calculated in its first time of testing when done in accordance with test A. For consistency, the point in time of measurement of the amount of water absorbed must be the same. Thus, this data can be reported at, for example, one minute, two minutes or any other convenient time. The values are reported at 1 and 2 minutes herein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings where like reference numerals represent like structure or like process steps and, in particular, to FIG. 1 which schematically illustrates apparatus 10 for forming and treating a high hydrohead fibrous porous web material to improve the retentive water absorbency and retentive water acquision rate of the material. The process may be initiated by supplying pellets (not shown) of a fiber-forming thermoplastic material which may be, for example, a polyolefin or a blend of polyolefins such as polypropylene or polyethylene into the hopper 12 of an extruder 14.
While any thermoplastic fiber forming material may be useful, one desirable material is a polypropylene which may be obtained from the Shell Chemical Company under the trade designation 5A09. The Shell 5A09 polypropylene has a melt flow rate of about 40 decigrams per minute when measured in accordance with ASTM D 1238 at 230 degrees Centigrade.
Many other thermoplastic polymers are suitable for use as the fiber forming polymer. Specific, non-limiting examples of such polymers include: polyolefins such as low density polyethylene, linear low density polyethylene and high density polyethylene. The materials may be plasticized with suitable plasticizers, and other additives known in the art may be added to achieve the desired physical characteristics.
Elastomeric polymers may be used to form the fibrous porous web. Such polymers include: polyester elastomeric materials, polyurethane elastomeric materials, polyetherester elastomeric materials, polyamide elastomeric materials, and the various elastomeric A-B-A' block copolymer materials disclosed in U.S. Pat. No. 4,663,220 to Wisneski et al, which is hereby incorporated by reference.
Neat or a solution of a surface active agent is sprayed onto the fibers as they are formed or on the formed web 22 from a spraying apparatus which may be a spray boom 19. The surface active agent may be, for example, an emulsion, a wetting agent or a detergent having a hydrophile-lipophile balance at a least about 6 or greater. The surface active agent may be nonionic, cationic or anionic. If the surface active agent is nonionic, it is desirable that it have at least 3 ethylene oxide groups. One desirable surface active agent is a surfactant is Na-di-(2-ethlyhexyl) sulphosuccinate which may be obtained from American Cyanamide under the trade designation Aerosol OT. Aerosol OT has an equivalent hydrophile-lipophile balance of greater than about 13. It has been reported that the hydrophile-lipophile balance of Aerosol OT is about 13.5. See, U.S. Pat. No. 4,013,863 to van Osenbruggen, et al. at Table I, therein, and U.S. Pat. No. 3,904,728 to Davis, et al. Another surface active agent which may be used may be obtained from the Rohm & Haas Company under the trade designation Triton X-102. Rohm & Haas literature states that the X-102 is a nonionic ocytlphenol liquid surfactant having from 12-13 ethylene oxide units. The material is about 73%, by weight, ethylene oxide, has a Brookfield viscosity at 25 degrees C. (12rpm) of 30, and has a calculated hydrophile-lipophile balance of about 14.6. Other Triton brand name materials may be utilized in the present invention. Exemplary of which are Triton X-35 which is a nonionic octylphenol series material having three ethylene oxide units and a calculated hydrophile-lipophile balance of 7.8; Triton RW 50 which is a cationic material, (t-C 12-14 NH(CH 2 CH 2 O) 5 H), having an average of five ethylene oxide units and a measured hydrophile-lipophile balance of 12-14 Triton RW 100 which is a cationic material, (t-C 12-14 NH(CH 2 CH 2 O) 10 H), having an average of 10 ethylene oxide units and a measured hydrophile-lipophile balance of 16; Triton DF 12 which is a nonionic modified polyethoxylated alcohol that has a calculated hydrophile-lipophile balance of 10.6 and Triton DF 18 which is a nonionic biodegradable modified alcohol that has a calculated hydrophile-lipophile balance of 11.3.
It is desirable for the surface concentration of the surface active agent on the surface of the fibers of the web to be at least about 0.05 weight percent of the web. For example, from about 0.05 percent, by weight, to about 3 percent, by weight of the web. More particularly, from about 0.10 percent, by weight, to about 1.0 percent, by weight of the web. For example, from about 0.1 percent, by weight, to about 0.4 percent, by weight, of the web. Even more particularly, from about 0.20 percent, by weight, to about 0.30 percent by weight of the web. In one embodiment the surface concentration is about 0.30 percent by weight of the web 22.
Because not all of the sprayed surface active agent remains on the fibers, the amount of surface active agent applyed to the fibers is generally greater than the amount desired to be present on the surface. Accordingly, the amount of surface active agent sprayed on the fibers may vary with the surface active agent used, the thermoplastic material used to form the web and/or the process conditions of forming the web.
The temperature of the blend is elevated within the extruder 14 by a conventional heating arrangement (not shown) to melt the polymer and pressure is applied to the polymer by the pressure-applying action of a turning screw (not shown), located within the extruder, to form the polymer into an extrudable composition. Preferably the polymer is heated to a temperature of at least about 175 degrees Centigrade if polypropylene is utilized as the fiber forming polymer. The polymer is then forwarded by the pressure applying action of the turning screw to a fiber forming arrangement 16 which may, for example, be a conventional meltblowing die arrangement. Meltblowing die arrangements are described in U.S. Pat. Nos. 3,978,185 to Buntin et al and 3,849,241 to Buntin et al. Both of these patents are hereby incorporated by reference. The elevated temperature of the polymer is maintained in the fiber forming arrangement 16 by a conventional heating arrangement (not shown). The fiber-forming arrangement generally extends a distance in the cross-machine direction which may be about equal to the width of the fibrous porous nonwoven web which is to be formed by the process. The fiber-forming arrangement 16 extrudes and attenuates the fibers 18 and directs them onto a moving forming screen 20. Upon impacting the forming screen 20, the fibers 18 may, depending upon known process conditions, adhere to each other to form the fibrous porous web 22. If not, a nip roller 24, in combination with the forming screen 20 can act to make the web 22 self supporting. If desired, the web 22 may be passed through a thermal point bonding arrangement 26 including rollers 28 and 30 to consolidate the web 22 even further. The combination of elevated temperature and elevated pressure conditions which effect extrusion of the polymer will vary over wide ranges. For example, at higher elevated temperatures, lower elevated pressures will result in satisfactory extrusion rates and, at higher elevated pressures of extrusion, lower elevated temperatures will effect satisfactory extrusion rates.
During or shortly after formation of the fibrous porous web 22, the high hydrophile-lipophile surface active agent is sprayed onto the surface of the fibers forming the web 22. In many instances the heat of the molten fibers 18 cooling after extrusion will be sufficient to effect drying of the high hydrophile-lipophile balance surface active agent. However, in some instances, the web 22 will have to be passed through a heating arrangement 32 which can include heating cans 34 and 36 to effect drying. The heating can drying temperature will vary with the surface active agent and polymer utilized. In any event the drying conditions are to be adjusted so that at least about 0.05, weight percent of the resultant web 22, of surface active agent will be on the surface of the web 22. For example, from about 0.05 percent, by weight, to about 3 percent, by weight of the web 22 of surface active agent will be on the surface of the web 22. More particularly, from about 0.10 percent, by weight, to about 1.0 percent, by weight of the web 22, of surface active agent will be on the surface of the web 22. For example, from about 0.1 percent, by weight, to about 0.4 percent, by weight, of the web 22, of the surface active agent will be on the surface of the web 22. Even more particularly, from about 0.20 percent, by weight, to about 0.30 percent by weight of the web 22, of surface active agent will be on the surface of the web 22.
Determination of the weight percentage of the surface active agent on the surface of the web at this point in the process can be determined by: (1) weighing the initial sample of material; (2) quantitatively extracting the surface active agent from the surface of the web 22 using an appropriate solvent; (3) determining the amount of surface active agent in the extraction solvent by such means as ultraviolet spectroscopy, infra-red spectroscopy, gravimetric analysis etc. (This may require making up a series of concentration standards of the surface active agent in the extracting fluid to calibrate the analytical equipment/method/technique. Manufactures of surface active agent often will supply methods for determining surface active agent quantitatively and qualitatively.); and (4) dividing the amount of surface active agent by the initial web 22 sample weight and multiplying by 100.
Once the high hydrophile-lipophile balance surface active agent has been applied to the surface of high hydrohead the web 22, the web 22 is passed through the gaps of two conventional corona discharge units 38. The two corona units are arranged so one treats one side of the web 22 and the other corona unit treats the other side of the web 22. One desirable corona discharge unit can be obtained from Enercon Ind. Corporation under trade designation Model SS 1223. The gaps of the corona discharge treatment apparatus may be maintained at about 0.065 inches. Standard metal rolls are used as the ground electrode. The base metal ground electrode roll may be buffered with 1 wrap of 0.5 mil polyester to substantially prevent arcing of the corona unit and pinholing in the high hydrohead fibrous porous web 22. Such buffering reduces the effectiveness of the corona discharge unit by approximately 20% for each wrap of 0.5 mil film used. The line speed of the high hydrohead web material 22 and the voltage and amperage of the corona discharge unit 38 are adjusted so that the equivalent of at least about 0.8 watt minute per square foot per side of corona discharge is applied to the web material 22. For example, the equivalent of from about 0.8 to about 15 watt minute per square foot per side of the web material 22 of corona discharge may be applied to the web material 22. Accordingly, the equivalent of from about 1 to about 10 watt minute per square foot per side of the web material 22 of corona discharge may be applied to the web material 22. More particularly, the equivalent of from about 2 to about 8 watt minute per square foot per side of the web material 22 of corona discharge may be applied to the web material 22.
Once the corona discharge unit 38 has applied the appropriate amount of charge to the web material 22, the web material 22, may be wound up on a storage roll 40. The corona treated web material 22 may later be used in a wide variety of applications which require or desire utilization of a material having acceptable retentive water absorbency and retentive water acquision rates. This method of treating a high hydrohead fibrous porous web material 22 has been found to increase the web's retentive acquision rate (averaged normalized rate of water absorption in subsequent reabsorptions as compared to the initial absorption rate) and retentive absorbency (averaged normalized amount of water absorbed in subsequent reabsorptions as compared to the amount initially absorbed).
Another embodiment is schematically illustrated in FIG. 2. In this situation the surface active agent may be applied in neat form or from solution by any of a number of conventional application methods. Exemplary of which is dip-and-squeeze. The dip-and-squeeze method is illustrated in FIG. 2 with the dip-and-squeeze apparatus 42 including a dipping bath 44 and a pair of squeezing rollers 46 and 48. In this process at least about 0.05%, by weight, of the web material 22 of high hydrophile-lipophile balance surface active agent is applied to the web material 22. For example, from about 0.05% to about 3%, by weight of the two web material, of high hydrophile-lipophile balance surface active agent may be applied to the web material 22. Even more particularly, from about 0.1% to about 1%, by weight of the web material 22, of high hydrophile-lipophile balance surface active agent may be applied to the material 22. More particularly, from about 0.1% to about 0.4%, by weight of the web material 22, of high hydrophile-lipophile balance surface active agent may be applied to the web material 22. Even more particularly, from about 0.2% to about 0.3% by weight of the web material 22, of high hydrophile-lipophile surface active agent may be applied to the web material 22. The remainder of the process is the same as the process described with respect to FIG. 1.
Of course, other conventional methods can be used for the production of the nonwoven web 22.
EXAMPLE
In order to demonstrate the improved retentive water absorbency and improved retentive water acquision rate of corona discharge treated high hydrophile-lipophile balance web materials of our invention, samples of commercially available wet wipers available from the Kimberly-Clark Corporation under the trademark Kimtex were treated in accordance with the teachings of the present invention. The wiper material was an approximate 2 ounce per square yard meltblow polypropylene material which had already been treated with a sufficient amount of Aerosol OT, Na-di(2-ethlyhexyl) sulphosuccinate, to have a surface concentration of Aerosol OT of about 0.30 weight percent of about 0.006 ounce per square yard. This web material was subjected to corona discharge treatment in accordance with our invention. The amount of corona discharge applied to the sample was varied by varying the line speed of the web material as it moved through the gaps of each of the two corona discharge electrodes. Each of the two electrodes were three feet in length and had their gap set at 0.065 inch and the power supply was set at 1.25 kilowatts for each of the two electrodes. The ground roll of each electrode was buffered with one wrap of 0.5 mil polyester to prevent arcing and pinholing. As has been previously stated this buffering reduces the effectiveness of the corona discharge by about 20 percent. Samples were made with the line speed (1s) of the web set a 25, 50, 100, 300, 400 and 600 feet per minute. The corresponding watt-min per square foot per side of corona discharge values are 13.3, 6.6, 3.3, 1.1, 0.83 and 0.55, respectively. For example, the corona charge placed on each side of the 400 feet per minute sample can be calculated as follows: 1250 watts per side times 0.80 efficiency divided by three feet electrode length divided by 400 feet per minute equals 0.83 watt min. per square foot per side.
Testing of these materials and samples of non-corona treated material was conducted in accordance with Test A. The results of this testing is reported below in the Table, below.
Decrease Averaged Decrease Decrease Total Actual Normalize d Average in Average Normalized in Average in Average Sample Sample Normalized Water Absorbed Water Absorbed Normalized Normalized Water Absorbed Normalized Water Normalized Water Sample Weight Weight Water Absorbed (g) Rate Rate (g) (g water/g wiper) Rate Rate (g) Absorbed in Grams Absorbed in Grams I. D. (g) (g) 1.2 sec 2.4 sec (g/sec) (g/g.sup.4 sec) 1 min 2 min 1 min 2 min (g/g.sup.4 sec) (%) 1 min 2 min At 1 Min. (%) At 2 Min. (%) UT-1(a) 1.20 1.17 0.50 1.00 0.417 0.357 3.20 3.80 2.74 3.26 0.398 NA 2.84 3.40 NA NA UT-2(a) 1.08 1.05 0.45 1.00 0.417 0.398 3.12 3.70 2.98 3.53 UT-3(a) 1.13 1.10 0.40 1.10 0.458 0.418 3.20 3.87 2.92 3.53 UT-4(a) 1.13 1.10 0.40 1.00 0.458 0.418 2.97 3.62 2.71 3.30 UT-1(b) 1.20 1.17 0.20 0.70 0.292 0.250 2.20 2.70 1.89 2.31 0.245 38 1.93 2.37 32 30 UT-2(b) 1.08 1.05 0.30 0.70 0.292 0.279 2.25 2.70 2.15 2.58 UT-3(b) 1.13 1.10 0.23 0.68 0.283 0.258 2.25 2.78 2.03 2.53 UT-4(b) 1.11 1.08 0.00 0.50 0.208 0.193 1.80 2.20 1.67 2.04 UT-1(c) 1.20 1.17 0.00 0.00 0.000 0.000 0.00 0.00 0.00 0.00 0.048 88 0.93 1.18 67 65 UT-2(c) 1.10 1.07 0.00 0.20 0.083 0.078 1.50 1.90 1.41 1.78 UT-3(c) 1.15 1.12 0.00 0.00 0.000 0.000 1.15 1.46 1.03 1.31 UT-4(c) 1.13 1.10 0.00 0.30 0.125 0.114 1.40 1.77 1.28 1.61 UT-1(d) 1.20 1.17 0.00 0.00 0.000 0.000 0.00 0.00 0.00 0.00 0.000 100 0.71 0.87 75 74 UT-2(d) 1.08 1.05 0.00 0.00 0.000 0.000 0.72 0.95 0.69 0.91 UT-3(d) 1.13 1.10 0.00 0.00 0.000 0.000 1.15 1.40 1.05 1.28 UT-4(d) 1.11 1.08 0.00 0.00 0.000 0.000 1.18 1.40 1.10 1.30 25-1(a) 0.92 0.89 0.60 1.10 0.458 0.516 3.10 3.70 3.49 4.17 0.478 NA 3.51 4.16 NA NA 25-2(a) 0.99 0.96 0.60 1.10 0.458 0.479 3.15 3.75 3.29 3.92 25-3(a) 0.98 0.95 0.80 1.00 0.417 0.440 3.55 4.15 3.75 4.38 25-1(b) 0.95 0.92 0.95 1.20 0.500 0.545 3.15 3.70 3.44 4.03 0.536 0 3.28 3.86 7 7 25-2(b) 0.97 0.94 0.75 1.15 0.479 0.511 2.95 3.50 3.15 3.74 25-3(b) 0.92 0.89 0.65 1.17 0.488 0.550 2.88 3.38 3.25 3.81 25-1(c) 0.92 0.89 0.68 1.08 0.450 0.507 2.84 3.35 3.20 3.78 0.470 2 3.00 3.56 15 14 25-2(c) 0.98 0.95 0.68 1.05 0.438 0.463 2.70 3.22 2.85 3.40 25-3(c) 0.98 0.95 0.53 1.00 0.417 0.440 2.78 3.32 2.94 3.51 25-1(d) 0.95 0.92 0.50 0.85 0.354 0.386 2.30 2.77 2.51 3.02 0.458 4 2.76 3.30 21 21 25-2(d) 0.91 0.88 0.49 1.00 0.417 0.475 2.51 2.99 2.36 3.41 25-3(d) 0.97 0.94 0.65 1.15 0.479 0.511 2.72 3.24 2.90 3.46 50-1(a) 1.10 1.07 0.80 1.20 0.500 0.469 3.50 4.20 3.28 3.94 0.396 NA 3.31 3.96 NA NA 50-2(a) 1.08 1.05 0.60 1.00 0.417 0.398 3.42 4.10 3.27 3.92 50-3(a) 1.07 1.04 0.60 0.80 0.333 0.321 3.50 4.18 3.38 4.03 50-1(b) 1.03 1.00 0.60 1.10 0.458 0.459 3.10 3.72 3.11 3.73 0.448 0 2.92 3.51 12 11 50-2(b) 1.07 1.04 0.63 1.13 0.471 0.454 2.84 3.44 2.74 3.32 50-3(b) 1.10 1.07 0.60 1.10 0.458 0.429 3.10 3.70 2.91 3.47 50-1(c) 1.11 1.08 0.61 1.09 0.454 0.422 2.82 3.40 2.62 3.16 0.432 0 2.67 3.20 19 19 50-2(c) 1.08 1.05 0.62 1.20 0.500 0.478 2.75 3.41 2.63 3.26 50-3(c) 1.08 1.05 0.43 1.00 0.417 0.398 2.88 3.33 2.75 3.18 50-1(d) 1.10 1.07 0.53 0.90 0.375 0.351 2.50 3.02 2.34 2.83 0.372 6 2.42 2.96 27 25 50-2(d) 1.05 1.02 0.45 0.90 0.375 0.369 2.45 3.06 2.41 3.01 50-3(d) 1.03 1.00 0.47 0.95 0.396 0.397 2.50 3.04 2.51 3.05 100-1(a) 1.02 0.99 0.65 1.08 0.450 0.456 3.42 4.08 3.47 4.13 0.469 NA 3.42 4.07 NA NA 100-2(a) 1.10 1.07 0.65 1.05 0.450 0.422 3.52 4.20 3.30 3.94 100-3(a) 1.07 1.04 0.72 1.32 0.550 0.530 3.63 4.30 3.50 4.15 100-1(b) 1.05 1.02 0.75 1.20 0.500 0.492 3.10 3.65 3.05 3.59 0.428 9 2.88 3.41 16 16 100-2(b) 1.09 1.06 0.51 0.81 0.338 0.320 2.70 3.23 2.55 3.06 100-3(b) 1.00 0.97 0.30 1.10 0.458 0.474 2.93 3.48 3.03 3.60 100-1(c) 1.02 0.99 0.40 0.90 0.375 0.380 2.38 3.40 2.92 3.44 0.396 16 2.76 3.28 19 19 100-2(c) 1.10 1.07 0.40 0.92 0.383 0.359 2.82 3.35 2.64 3.14 100-3(c) 1.05 1.02 0.55 1.10 0.458 0.450 2.77 3.32 2.72 3.26 100-1(d) 1.00 0.97 0.40 0.90 0.375 0.388 2.60 3.10 2.69 3.21 0.413 12 2.65 3.15 23 23 100-2(d) 1.08 1.05 0.40 0.92 0.383 0.366 2.65 3.15 2.53 3.01 100-3(d) 1.02 0.99 0.57 1.15 0.479 0.485 2.68 3.20 2.72 3.24 300-1(a) 1.01 0.98 0.80 1.31 0.546 0.559 3.30 3.90 3.38 3.99 0.476 NA 3.30 3.96 NA NA 300-2(a) 1.00 0.97 0.53 1.08 0.450 0.465 3.15 3.75 3.26 3.88 300-3(a) 0.98 0.95 0.52 0.92 0.383 0.404 3.10 3.80 3.27 4.01 300-1(b) 0.96 0.93 0.64 1.10 0.458 0.494 2.52 3.00 2.72 3.24 0.547 0 2.95 3.47 11 12 300-2(b) 0.99 0.96 0.80 1.40 0.583 0.609 3.01 3.52 3.15 3.68 300-3(b) 1.00 0.97 0.80 1.25 0.521 0.539 2.88 3.38 2.98 3.50 300-1(c) 1.00 0.97 0.00 0.68 0.258 0.267 2.28 2.75 2.36 2.84 0.351 26 2.50 3.01 24 24 300-2(c) 1.00 0.97 0.00 0.80 0.333 0.344 2.45 2.97 2.53 3.07 300-3(c) 0.98 0.95 0.30 1.00 0.417 0.440 2.47 2.94 2.61 3.10 300-1(d) 1.00 0.97 0.40 0.90 0.375 0.388 2.48 2.99 2.56 3.09 0.449 6 2.72 3.23 18 18 300-2(d) 0.98 0.95 0.30 1.02 0.425 0.449 2.66 3.12 2.81 3.29 300-3(d) 0.95 0.92 0.54 1.12 0.467 0.509 2.56 2.04 2.79 3.32 400-1(a) 1.08 1.05 0.72 1.25 0.521 0.498 3.35 3.95 3.20 3.77 0.480 NA 3.23 3.83 NA NA 400-2(a) 1.08 1.05 0.70 1.32 0.550 0.525 3.42 4.04 3.27 3.86 400-3(a) 1.08 1.05 0.50 1.05 0.438 0.418 3.37 4.04 3.22 3.86 400-1(b) 1.08 1.05 0.23 0.80 0.333 0.318 2.50 3.10 2.39 2.96 0.276 43 2.30 2.82 29 26 400-2(b) 1.06 1.03 0.00 0.55 0.229 0.223 2.15 2.67 2.09 2.60 400-3(b) 1.08 1.05 0.14 0.72 0.300 0.287 2.52 3.02 2.41 2.88 400-1(c) 1.08 1.05 0.52 0.94 0.392 0.374 2.24 2.62 2.14 2.50 0.209 56 1.77 2.18 45 43 400-2(c) 1.08 1.05 0.00 0.00 0.000 0.000 1.22 1.62 1.17 1.55 400-3(c) 1.10 1.07 0.00 0.65 0.271 0.254 2.15 2.65 2.01 2.48 400-1(d) 1.05 1.02 0.45 0.80 0.333 0.327 2.50 2.97 2.46 2.92 0.306 36 2.21 2.66 32 31 400-2(d) 1.05 1.02 0.40 0.95 0.396 0.389 2.31 2.77 2.27 2.72 400-3(d) 1.09 1.06 0.80 0.51 0.212 0.201 2.01 2.46 1.90 2.33 600-1(a) 1.05 1.02 0.75 1.20 0.500 0.492 3.12 3.74 3.07 3.68 0.459 NA 3.22 3.81 NA NA 600-2(a) 1.05 1.02 0.55 1.05 0.438 0.431 3.35 3.97 3.29 3.90 600-3(a) 1.02 0.99 0.68 1.08 0.450 0.456 3.26 3.80 3.30 3.85 600-1(b) 1.01 0.98 0.39 0.99 0.412 0.422 2.80 3.31 2.87 3.39 0.395 14 2.65 3.18 18 17 600-2(b) 1.01 0.98 0.29 0.89 0.371 0.380 2.58 3.10 2.64 3.17 600-3(b) 1.01 0.98 0.40 0.90 0.375 0.384 2.40 2.91 2.46 2.98 600-1(c) 1.05 1.02 0.00 0.00 0.000 0.000 0.00 0.00 0.00 0.00 0.029 94 1.02 1.31 68 66 600-2(c) 1.00 0.97 0.00 0.05 0.021 0.022 1.45 1.87 1.50 1.93 600-3(c) 1.00 0.97 0.00 1.15 0.062 0.064 1.52 1.92 1.57 1.99 600-1(d) 1.00 0.97 0.00 0.00 0.000 0.000 0.00 0.21 0.00 0.22 0.033 93 1.01 1.37 69 64 600-2(d) 1.01 0.98 0.00 0.00 0.000 0.000 0.95 1.30 0.97 1.33 600-3(d) 1.00 0.97 0.00 0.45 0.095 0.098 2.00 2.48 2.07 2.56
The data of Table I may be interpreted as follows; (1) UT represents the non-corona treated samples whereas the 25, 50, 100, 300, 400, 600 represents the feet per minute of the web as it passed through the corona discharge gap; (2) three replicate samples of each treated material were taken with each of these being represented by the number 1 or 2 of 3; (3) each of the samples was subjected to testing in accordance with Test A four times with the first test being designated by the letter (a) the second represented by the letter (b) the third being represented by the letter (c) and the fourth being represented by the letter (d). Thus 600-3(d) stands for the results of the fourth time the third replicate sample of material treated at 600 feet per minute was tested in accordance with Test A.
From the above results reported in Table I, it is clear that materials treated in accordance with our invention line speeds of about 400 feet per minute or less (about 0.8 watt-min. per square foot per side or greater) have significantly smaller decreases in average normalized rate of water acquision and in averaged normalized water absorbed at one minute and two minutes. Such materials can be repeatedly reused as wiper materials helping both the environment because of less wipers being used and the user because less materials may be purchased.
While the invention has been described in detail with respect to specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing, may readily conceive of alterations to and variations of these embodiments. Such alterations and variations are believed to fall within the scope and spirit of the invention and the appended claims.
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A method of treating a high hydrohead fibrous porous web to increase its retentive acquision rate and retentive absorbency, as compared to untreated web, is disclosed.
The invention is also directed to products prepared by or preparable by the process.
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BACKGROUND
[0001] 1. Technical Field
[0002] Embodiments of the subject matter disclosed herein generally relate to methods and systems and, more particularly, to mechanisms and techniques for capturing video evidence of the initiation and/or progress of an emergency disconnect sequence.
[0003] 2. Discussion of the Background
[0004] During the past years, with the increase in price of fossil fuels, the interest in developing new production fields has increased dramatically. However, the availability of land-based production fields is limited. Thus, the industry has now extended drilling to offshore locations, which appear to hold a vast amount of fossil fuel.
[0005] The existing technologies for extracting the fossil fuel from offshore fields may use a system 10 as shown in FIG. 1 . More specifically, a blowout preventer stack (“BOP stack”) 11 may be rigidly attached to a wellhead 12 upon the sea floor 14 , while a Lower Marine Riser Package (“LMRP”) 16 may be retrievably disposed upon a distal end of a marine riser 18 , extending from a drill ship 20 or any other type of surface drilling platform or vessel. As such, the LMRP 16 may include a stinger 22 at its distal end configured to engage a receptacle 24 located on a proximal end of the BOP stack 11 .
[0006] In typical configurations, the BOP stack 11 may be rigidly affixed atop the subsea wellhead 12 and may include (among other devices) a plurality of ram-type blowout preventers 26 useful in controlling the well as it is drilled and completed. Similarly, the LMRP 16 may be disposed upon a distal end of a long flexible riser 18 that provides a conduit through which drilling tools and fluids may be deployed to and retrieved from the subsea wellbore. Ordinarily, the LMRP 16 may include (among other things) one or more ram-type blowout preventers 28 at its distal end, an annular blowout preventer 30 at its upper end, and multiplex (MUX) pods 32 .
[0007] A MUX pod system 40 , is shown in FIG. 2 and may provide between 50 and 100 different functions to the BOP stack and/or the LMRP and these functions may be initiated and/or controlled from or via the MUX BOP Control System.
[0008] The MUX pod 40 may be fixedly attached to a frame (not shown) of the LMRP and may include hydraulically activated valves 50 (called in the art sub plate mounted (“SPM”) valves) and solenoid valves 52 that are fluidly connected to the hydraulically activated valves 50 . The solenoid valves 52 are provided in an electronic section 54 and are designed to be actuated by sending an electrical signal from an electronic control board (not shown). Each solenoid valve 52 may be configured to activate a corresponding hydraulically activated valve 50 . The MUX pod 40 may include pressure sensors 56 also mounted in the electronic section 54 . The hydraulically activated valves 50 are provided in a hydraulic section 58 and may be fixedly attached to the MUX pod 40 .
[0009] A bridge between the LMRP 16 and the BOP stack 11 is formed that matches the multiple functions from the LMRP 16 to the BOP stack 11 , e.g., fluidly connects the SPM valves 50 from the MUX pod provided on the LMRP to dedicated components on the BOP stack or the LMRP. The MUX pod system is used in addition to choke and kill line connections (not shown) or lines that ensure pressure supply for the shearing function of the BOPs.
[0010] The bridge is shown in FIG. 3 and may include a pod wedge 42 configured to engage a receiver 44 on the BOP stack. The pod wedge 42 has plural holes (not shown), depending on the number of functions provided, that provides hydraulic fluids from the LMRP 16 to the BOP stack 11 .
[0011] In typical subsea blowout preventer installations, multiplex (“MUX”) cables (electrical) and/or lines (hydraulic) transport control signals (via the MUX pod and the pod wedge) to the LMRP 16 and BOP stack 11 devices so the specified tasks may be controlled from the surface. Once the control signals are received, subsea control valves are actuated and (in most cases) high-pressure hydraulic lines are directed to perform the specified tasks. Thus, a multiplexed electrical or hydraulic signal may operate a plurality of “low pressure” valves to actuate larger valves to communicate the high-pressure hydraulic lines with the various operating devices of the wellhead stack.
[0012] Examples of communication lines bridged between LMRPs and BOP stacks through feed-thru components include, but are not limited to, hydraulic choke lines, hydraulic kill lines, hydraulic multiplex control lines, electrical multiplex control lines, electrical power lines, hydraulic power lines, mechanical power lines, mechanical control lines, electrical control lines, and sensor lines. In certain embodiments, subsea wellhead stack feed-thru components include at least one MUX “pod” connection whereby a plurality of hydraulic control signals are grouped together and transmitted between the LMRP 16 and the BOP stack 11 in a single mono-block feed-thru component as shown, for example, in FIG. 3 .
[0013] When desired, ram-type blowout preventers of the LMRP 16 and the BOP stack 11 may be closed and the LMRP 16 may be detached from the BOP stack 11 and retrieved to the surface, leaving the BOP stack 11 atop the wellhead. For example, it may be necessary to retrieve the LMRP 16 from the wellhead stack in times of inclement weather or when work on a particular wellhead is to be temporarily stopped.
[0014] To retrieve the LMRP 16 from the wellhead stack, an Emergency Disconnect Sequence (“EDS”) may be initiated. An EDS may include a number of different functions that are to be performed by the LMRP 16 and the BOP stack. The functions of the EDS may be carried out by the LMRP 16 and/or the BOP stack as set forth above via the MUX pod 40 and/or the bridge. A particular EDS may include a predetermined number of functions. For example, one particular EDS may include eighteen (18) functions while another EDS may include twenty-five (25) functions. A particular EDS may take a predetermined period of time to complete. For example, one particular EDS may take 20 (twenty) seconds to complete while another EDS may take 25 (twenty-five) seconds to complete. An EDS may be initiated using an EDS system 50 as shown in FIG. 4 . An EDS may be initiated or fired by pressing an EDS button 52 located on a stack controller 54 located on the drill ship 20 . Once the EDS is fired, the functions included in that EDS may be performed until all of the functions are complete.
[0015] Verification that an operator initiated an EDS and/or of the progression of the EDS may be desired. Conventionally, such verification may be provided via a manual log 56 . When an operator selects or presses the EDS button 52 located on the stack controller 54 , the log 56 may be updated to reflect the initiation of the EDS. However, this conventional approach is problematic. For example, the accuracy of such a log may itself be in question and may need verification. Further, beyond the log, conventional systems may not include any additional tool to verify that the operator initiated the EDS.
[0016] Therefore, it is desired to provide a novel approach for capturing evidence of the initiation and/or progression of an EDS.
SUMMARY
[0017] According to one exemplary embodiment, there is an emergency disconnect sequence video capture system. The emergency disconnect sequence video capture system includes a stack screen on a drilling platform, the stack screen including an emergency disconnect sequence button to initiate an emergency disconnect sequence signal to be sent to a multiplex pod resulting in an emergency disconnect sequence including a plurality of functions being performed by devices in one or both of a lower marine riser package and a blowout preventer stack, and an emergency disconnect sequence function status indicator, either a video capture device aimed at the stack screen to automatically capture one or more of the initiation of the emergency disconnect sequence signal by the emergency disconnect sequence button and a progress of the emergency disconnect sequence indicated by the emergency disconnect sequence function status indicator as emergency disconnect sequence evidence, or a video card to capture video captures of one or more of the initiation of the emergency disconnect sequence signal by the emergency disconnect sequence button and a progress of the emergency disconnect sequence indicated by the emergency disconnect sequence function status indicator as emergency disconnect sequence evidence, and a storage connected to either the video capture device or the video card and configured to store said emergency disconnect sequence evidence.
[0018] According to another exemplary embodiment, there is an emergency disconnect sequence system. The system includes a blowout preventer stack, a lower marine riser package releasably connectable to the blowout preventer stack, a multiplex pod connected to the lower marine riser package, the multiplex pods to receive an emergency disconnect sequence signal and to transport electric and/or hydraulic control signals to devices in one or both of the lower marine riser package and the blowout preventer stack in response to the emergency disconnect sequence signal, a marine riser connected to the LMRP, a drilling platform connected to the marine riser, and a stack screen on the drilling platform, the stack screen including an emergency disconnect sequence button to initiate the emergency disconnect sequence signal sent to the multiplex pods resulting in an emergency disconnect sequence including a plurality of functions being performed by the devices in the one or both of the lower marine riser package and the blowout preventer stack, and an emergency disconnect sequence function status indicator, either a video capture device aimed at the stack screen to automatically capture one or more of the initiation of the emergency disconnect sequence signal by the emergency disconnect sequence button and a progress of the emergency disconnect sequence indicated by the emergency disconnect sequence function status indicator as emergency disconnect sequence evidence, or a video card to capture videos of one or more of the initiation of the emergency disconnect sequence signal by the emergency disconnect sequence button and a progress of the emergency disconnect sequence indicated by the emergency disconnect sequence function status indicator as emergency disconnect sequence evidence, and and a storage to store said emergency disconnect sequence evidence.
[0019] According to another exemplary embodiment, there is a method to capture emergency disconnect sequence evidence. The method includes receiving, into a computing device, a video image from either a video capture device aimed at a stack screen interface or from a video card, the video image including one or both of an initiation of an emergency disconnect sequence by an operator touching an emergency disconnect sequence button on the stack screen interface, and a progress of the emergency disconnect sequence indicated by an emergency disconnect sequence function status indicator, and storing, in a storage in communication with the computing device, the video image from the video capture device or the video card as the emergency disconnect sequence evidence.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. In the drawings:
[0021] FIG. 1 is a schematic diagram of a conventional offshore rig;
[0022] FIG. 2 is a schematic diagram of a MUX pod;
[0023] FIG. 3 is a schematic diagram of a feed-thru connection of a MUX pod attached to a subsea structure;
[0024] FIG. 4 is a schematic diagram of a conventional EDS system;
[0025] FIG. 5 is a schematic diagram of an EDS system according to an exemplary embodiment;
[0026] FIGS. 6 and 7 are schematic diagrams of EDS evidence according to an exemplary embodiment.
[0027] FIG. 8 is a flow chart of a method according to an exemplary embodiment.
DETAILED DESCRIPTION
[0028] The following description of the exemplary embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims. The following embodiments are discussed, for simplicity, with regard to the terminology and structure of an emergency disconnect sequence (“EDS”) system provided with a stack screen for initiating an EDS and/or monitoring the status of that EDS. However, the embodiments to be discussed next are not limited to these systems, but may be applied to other systems (e.g., diverter systems) that may include other interfaces (e.g., alarms screen, diverter screen, events screen, utility screen) for initiating and/or monitoring the status of other sequences (e.g., alarms, diverter sequences, events).
[0029] Reference throughout the specification to “an exemplary embodiment” or “another exemplary embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in an exemplary embodiment” or “in another exemplary embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
[0030] According to an exemplary embodiment, a video capture device may be aimed at a stack screen to automatically capture an initiation of an EDS signal by an EDS button and/or a progress of the EDS indicated by an EDS function status indicator as EDS evidence. The EDS evidence may be stored with a timestamp and subsequently replayed. In this way, that an operator initiated a particular EDS and/or the progression of the EDS may be verified. This may supplement or replace manual log verification.
[0031] According to an exemplary embodiment shown in FIG. 5 , an EDS system 500 may include a BOP stack 502 , a LMRP 504 , MUX pods 506 , a marine riser 508 , a drilling platform 510 , a stack screen 512 , a video capture device 516 , and a computing device 522 . The LMRP 504 may be releasably connectable to the BOP stack 502 . The MUX pods 506 may be connected to the LMRP 504 . The marine riser 508 may be connected to the LMRP 504 . The drilling platform 510 may be connected to the marine riser 508 . The stack screen 512 , video capture device 516 , and the computing device 522 may be located on the drilling platform 510 .
[0032] The MUX pods 506 may receive an EDS signal and may transport electric and/or hydraulic control signals to devices in the LMRP 504 and/or the BOP stack 502 in response to the EDS signal.
[0033] The stack screen 512 may include a number of different controls and displays including an EDS button 514 and an EDS function status indicator 515 . The EDS button 514 may initiate the EDS signal sent to the MUX pod and may result in an EDS including a plurality of functions being performed by the devices in the LMRP 504 and/or the BOP stack 502 . The EDS may include a predetermined number of functions as the plurality of functions and may last for a predetermined period of time. Each function may last a corresponding amount of time. The EDS function status indicator 515 may indicate a status (e.g., complete) of a function of the plurality of functions. In an exemplary embodiment, the EDS button 514 and the EDS function status indicator 515 are two separate elements on the stack screen 512 . In another exemplary embodiment, the EDS button 514 and the EDS function status indicator 515 may be the same element.
[0034] In an exemplary embodiment, the stack screen 512 may be a touch-screen. The stack screen 512 may include the EDS button 514 and the EDS function status indicator 515 as touch-screen displays. In another exemplary embodiment, the stack screen may be a computer display. The stack screen may include the EDS button as a selectable control on the computer display and the EDS function status indicator as a display on the computer display. In another exemplary embodiment, the stack screen may be a physical control panel. The stack screen may include the EDS button as a physical button and the EDS function status indicator as a display.
[0035] The video capture device 516 may be aimed at the stack screen 512 to capture the initiation of the EDS signal by the EDS button and/or a progress of the EDS as indicated by the EDS function status indicator as EDS evidence. The computing device 522 may include a storage 520 . The storage 520 may store the EDS evidence. In another exemplary embodiment, the computing device 522 may be in communication with a remote storage.
[0036] The video capture device 516 may be a digital video capture device. The computing device 522 may include software including video capture and playback capabilities, such as the QNX operating system by QNX Software Systems Co. The computing device 522 may be in communication with and drive the video capture device 516 . The video capture device 516 may include a video capture device lens 518 . The video capture device lens 518 may be aimed at the stack screen 512 . As such, the video capture device 516 may capture the initiation of the EDS signal by the EDS button and/or the progress of the EDS as indicated by the EDS function status indicator as an EDS video. The storage 520 may store the EDS video as a digital video file.
[0037] According to an exemplary embodiment shown in FIGS. 6 and 7 , EDS evidence 600 may be captured by the video capture device 516 as an EDS video. The EDS video may include a timestamp 602 indicating the time and date of the EDS video. In one application, the time stamp may be as accurate as desired, e.g., to the second. In FIG. 6 , the EDS video shows an operator's finger initiating an EDS by touching the EDS button 514 . Thus, the time when the operator has initiated the EDS sequence may be recorded. Other actions of the operator may also be recorded. In FIG. 7 , the EDS video shows a progress of the EDS as indicated by the EDS function status indicator 515 . In an exemplary embodiment, the EDS function status indicator 515 may indicate the status of a function by changing color. In another exemplary embodiment, the EDS function status indicator 515 may indicate the status of a function using other function status indicators. Thus, this system may be able to record each function that is being activated by the operator and also the time progression of each function. In one embodiment, any action of the operator on the stack screen may be recorded with the associated timestamp.
[0038] The operation of the EDS system 500 of FIGS. 5-7 is now described with reference to FIG. 8 , which is a flow chart of a method 800 according to an exemplary embodiment.
[0039] In operation 802 , the method may begin. Before initiation of an EDS, the video capture device 516 may be initiated. In an exemplary embodiment, the software including video capture and playback capabilities of the computing device 522 may initialize the video capture device 516 . The video capture device lens 518 may be aimed at the stack screen 512 . The video capture device 516 may then capture a video image of an initiation of an EDS by an operator touching the EDS button 514 ( FIG. 6 ). Additionally and/or alternatively, the video capture device may capture a progress of the EDS as indicated by the EDS function status indicator 515 ( FIG. 7 ). In operation 804 , the computing device 522 may receive the video image of the initiation of the EDS by the operator touching the EDS button 514 and/or the progress of the EDS as indicated by the EDS function indicator 515 (i.e., the EDS evidence). In operation 806 , the computing device 522 may store the EDS evidence in the storage 520 . In an exemplary embodiment, the computing device 522 provides the timestamp 602 that is added to the video image. In another exemplary embodiment, the video capture device 516 provides the timestamp 602 that is part of the video image. In operation 808 , the computing device plays back the EDS evidence. In operation 810 , the operation ends. In this way, a time-stamped video of the entire EDS as it is happening on the stack screen 512 may be obtained. The video may serve as a time-stamped record of the initiation of an EDS and/or which functions were fired and when they were fired at any particular time instant.
[0040] In another exemplary embodiment, the video capture feature may be employed to capture videos of functions to be fired during different types of well control situations that may not require the emergency disconnect sequence. This may be effectively used as a training tool for field service engineers and rig personnel.
[0041] In another exemplary embodiment, the video capture feature can be employed to capture videos of sequences in other devices like Diverter systems for Diverter Packer Close sequences, adjusting regulators, setting up the MUX BOP Control System for normal drilling operations etc.
[0042] In another exemplary embodiment, the video capture device may be replaced by and/or include a microphone positioned near the stack screen. The microphone may capture the initiation of the EDS signal by the EDS button and/or the progress of the EDS as indicated by the EDS function status indicator as EDS audio. For example, the EDS button may be configured to cause an audible sound upon selection by an operator. Audible sounds may indicate progress points of the EDS.
[0043] In another exemplary embodiment, the video capture device may be replaced by and/or include a logging system in communication with the EDS button and/or the EDS function status indicator. The logging system in communication with the EDS button and/or EDS function status indicator may include computer executable instructions causing the computing device to monitor operator interactions with the stack screen 512 . The logging system may capture, in a logging file constituting the EDS evidence, an operator interaction of selecting the EDS button and/or the progress of the EDS as indicated by the EDS function status indicator.
[0044] The EDS evidence (and any other evidence that may be recorded or logged by the system) may be then transmitted wireless or wired to a storage system located on ground. In this way, in the eventuality of the total failure of the rig, e.g., fire or flooding, the EDS evidence may not be destroyed together with the rig. The processor handling the recording of the EDS evidence may be programmed to recognized when the EDS evidence is recorded and to transmit in real time the recorded data to a satellite or other station as the evidence. In one exemplary embodiment, when the operator starts the EDS sequence, the processor may be configured to connect to a satellite or a station for transmitting the information being recorded for safety. Thus, the computing device 522 may include or may be connected to corresponding electronic circuitry, like a transmitter, receiver, amplifier, antenna, or the like for communicating with a satellite or an earth based station.
[0045] The disclosed exemplary embodiments provide EDS systems and a method for capturing video evidence of the initiation and/or progress of an emergency disconnect sequence. It should be understood that this description is not intended to limit the invention. On the contrary, the exemplary embodiments are intended to cover alternatives, modifications and equivalents, which are included in the spirit and scope of the invention as defined by the appended claims. Further, in the detailed description of the exemplary embodiments, numerous specific details are set forth in order to provide a comprehensive understanding of the claimed invention. However, one skilled in the art would understand that various embodiments may be practiced without such specific details.
[0046] Although the features and elements of the present exemplary embodiments are described in the embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the embodiments or in various combinations with or without other features and elements disclosed herein.
[0047] This written description uses examples of the subject matter disclosed to enable any person skilled in the art to practice the same, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims.
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Emergency disconnect sequence (EDS) video capture systems and method. The EDS video capture system includes a stack screen on a drilling platform, the stack screen including an EDS button to initiate an EDS signal to be sent to multiplex pods resulting in an EDS including a plurality of functions being performed by devices in one or both of a lower marine riser package and a blowout preventer stack, and an EDS function status indicator. The indicator is either a video capture device aimed at the stack screen to automatically capture one or more of the initiation of EDS signal by the EDS button and a progress of the EDS indicated by the EDS function status indicator as EDS evidence or a video card to capture one or more of the initiation of the EDS signal by the EDS button and a progress of the EDS indicated by the EDS function status indicator as EDS evidence, and a storage to store the EDS evidence.
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RELATED APPLICATION
This application is a continuation in part of applicant's copending application Ser. No. 06/921,218, filed Oct. 20, 1986, now U.S. Pat. No. 4,925,664, entitled "Spider Toxins and Methods for their Use as Blockers of Calcium Channels and Amino Acid Receptor Function," which application is incorporated herein by reference.
BACKGROUND
1. The Field of the Invention
The present invention generally relates to the isolation of certain toxins from spider venoms and the use of those toxins as inhibitors of the functions of ion channels. In particular, the present invention relates to spider venom toxins and their use as blockers of calcium channels in the central nervous and neuromuscular systems of organisms, including humans.
2. The Background of the Invention
Movement of calcium ions across cell membranes is a critically important event in the normal functioning of excitable tissues such as vascular smooth muscle, cardiac muscle, and the central nervous system. Influx of calcium ions through specialized channels in the cell membranes regulates release of substances such as hormones and neurotransmitters.
The movement of calcium ions also regulates contraction of heart muscle and of vascular smooth muscle in the wall of blood vessels. Abnormal influx of calcium ions has been reported to play a role in the pathogenesis of various cardiovascular disorders (e.g., anoxic/ischemic heart disease), and drugs capable of blocking the movement of calcium through calcium channels have been used for treatment of cardiac arrhythmias, coronary artery disease, and cardiomyopathy.
The currently used drugs, however, have non-specific physiological effects and varying tissue specificities that can lead to undesirable side-effects in patients. Moreover, there are several known subtypes of calcium channels with varying physiological actions and no drug that specifically blocks certain of these subtypes is known.
In the nervous system, calcium influx into the presynaptic nerve terminal via calcium channels is a necessary prerequisite for the release of chemical neurotransmitter at synapses and thus for the proper functioning of these synapses. Lowering of the extracellular calcium concentration is routinely used by neurophysiologists to reduce or abolish synaptic transmission in isolated pieces of nervous tissue.
It has not been possible, however, to specifically affect synaptic transmission in vivo in the central nervous system ("CNS") by manipulating the function of neuronal calcium channels With the exception of the omega-conotoxin recently isolated from the venom of the marine snail Conus geographus, no drug with sufficiently specific or potent effects on CNS calcium channels is known.
Abnormal influx of calcium is thought to be very important in the pathogenesis of several CNS disorders, including anoxic/ischemic (stroke) damage, epilepsy, and the neuronal death associated with chronic epilepsy. Again, the paucity of chemical agents that potently and specifically block CNS calcium channels has impeded the development of an effective drug therapy for these prevalent neurological problems.
Thus, it would be a very considerable improvement in the art if it were possible to develop chemical agents that specifically and potently block calcium channel function in the CNS. In particular, it would be an advancement in the art to provide a specific blocker for particular subtypes of calcium channel. Similarly, it would be an advancement in the art to provide a specific blocker of calcium channels in the CNS.
Such chemical compositions and methods for their use are disclosed and claimed below.
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
The present invention is related to the isolation, identification, and use of spider venoms and toxins contained within these venoms. In particular, the present invention is related to the isolation and use as calcium channel blockers of certain toxins from spider venom.
As discussed above, calcium channels are intimately involved in the functions of the cardiovascular system since calcium influx affects contraction of cardiac muscle and vascular smooth muscle. Similarly, calcium influx into nerve cells is required for the release of chemical neurotransmitter substances at synapses and, therefore, for the normal functioning of the nervous system. Calcium influx into nerve cells is also involved in mediating certain electrical responses of those cells. Abnormal calcium influx into cells is associated with serious cardiovascular and neurological disorders.
The present invention is related to obtaining toxins from spider venoms, which toxins have specific and potent blocking effects on calcium channels within the organism.
Within the scope of the present invention, spider venom is obtained by milking spiders of various species. That is, the spider venom is obtained by electrical stimulation of the spider to cause release of the venom and subsequent suction in order to collect the released venom. This assures that impurities, which have traditionally been contained within spider venoms obtained by conventional techniques, are eliminated.
Spider venoms are known to be a complex mixture of enzymes, peptide toxins, nucleotides, free amino acids, and other molecules. As a result, in order to obtain useful spider toxins it is necessary to separate the various components of the whole spider venom. According to one embodiment of the present invention, whole venoms are fractionated by gel filtration to separate components of the venom by relative molecular mass. It will be appreciated, however, that any type of fractionation technique or other technique may be useful to obtain the spider venom toxins necessary for use in the present invention.
A group of specific spider venoms has been isolated and used extensively in the context of the present invention. The spiders that have been used within the scope of the present invention are Agelenopsis aperta spiders. Agelenopsis spiders are members of the funnel-web grass spider family Agelenidae and are commonly found in meadows and other grassy areas within the western United States.
The primary specific toxin which falls within the scope of the present invention has been isolated from the Agelenopsis spider. In particular, a relatively high molecular weight toxin that suppresses synaptic transmission in the vertebrate central nervous system by blocking calcium channels. For ease of identification this toxin will be sometimes generally referred to as "AG1" during the present description of the invention.
AG1 has been identified by amino acid sequencing techniques as a 48 amino acid peptide. The toxin is found to have the following sequence: ##STR1## The composition has a molecular weight of approximately 5274.
The gene which produces the AG1 toxin has been identified by employing a new procedure. The procedure uses a "polymerase chain reaction" (PCR) conducted under conditions which have recently been identified in the relevant literature. See, R. K. Saiki et al., Science 230, p. 1350 (1985); Saiki et al., "Primer-Directed Enzymatic Amplification of DNA with a Thermostable DNA Polymerase," Science 239, 487 (January 1988), which are collectively incorporated herein by this reference.
In order to clone the toxin gene two oligonucleotide primers were prepared. The first primer was specific only for the "poly A" tail of the mRNA. The second oligonucleotide primer was engineered from the cDNA of the coding gene sequence.
All of the mRNA in the RNA population was reverse transcribed to cDNA using the d(T) tailed primer. The specificity in the procedure comes with the amino terminal primer which is designed specifically from the protein sequence. Thus, only the cDNA which contains this sequence will be efficiently amplified in this system, as described in Saiki, et al.
The analysis of the anchored PCR products obtained from the reverse transcribed Agelenopsis venom gland mRNA are shown in FIG. 2, as described in greater detail below. Southern hybridization with the internal probe confirmed the correct gene sequence. DNA sequencing of this anchored PCR product confirmed that it contained the complete coding sequence of AG1, as well as all DNA sequences preceding the poly (A) tail. The sequence of the gene is set forth in Table 4 below.
Analysis of the translated peptide sequence indicated a protein having a molecular weight of approximately 5,280 daltons, with 8 cysteine residues. This data is set forth below in Table 5. This data indicates that the gene sequence identified is that which is responsible for the production of AG1 in the Agelenopsis aperta spider.
Identification of the gene responsible for the production of AG1 facilitates the production of the toxin by using i.e., recombinant DNA techniques, and may result in the ability to genetically engineer higher plants with the ability to produce the toxin.
It has been found that AG1 produces blockade of synaptic transmission under certain conditions without affecting axonal conduction of action potentials. The AG1 toxin affects transmission of the nerve impulse across the synapse.
AG1 is also found to block transmission in certain central nervous system cells by blocking calcium currents. It is particularly noteworthy that AG1 is not acutely toxic to the cells tested and does not affect the electric excitability of the neurons themselves. Thus, this suggests that AG1's effects are not produced by acute cytotoxic action. Simply stated, CNS transmission is blocked without damaging the cells involved.
It is a primary object of the present invention to provide calcium channel blockers and methods for their use which have specific and identifiable effects on an organism.
Another object of the present invention is to provide a specific calcium channel blocker which affects the central nervous system.
It is another object of the present invention to provide calcium channel blockers for use as research tools and for use in the clinical setting.
It is also an object of the present invention to identify the amino acid sequence of the AG1 toxin responsible for blocking synaptic transmission in the central nervous system.
It is a similar object of the present invention to isolate and identify the gene responsible for production of the AG1 toxin that blocks synaptic transmission.
These and other objects of the present invention will become apparent upon reading the following detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing representing the procedure employed in identifying and isolating the gene responsible for the production of AG1.
FIG. 2 is an autoradiograph of the southern analysis of the reaction products confirming the isolation and identification of the gene responsible for the production of AG1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As discussed above, the present invention is related to new and unique calcium channel blockers, methods for their isolation, and methods of application of such molecules. In particular, the present invention relates to the use of isolated toxins obtained from spider venom for use as specific calcium channel blockers.
It has been found within the scope of the present invention that certain spider venoms may selectively act on the central nervous system. More particularly, it has been found that spider venoms can have specific activities on calcium channels within the organism.
An additional benefit of the present invention is that the isolated toxins act without significant cytotoxicity. Thus, the toxins do not block channels by destroying the cells within the systems in which they are active. Additionally, the toxins of the present invention generally act without affecting axonal conduction within the nervous system. It will be appreciated, therefore, that only calcium channels are affected by the toxin that acts on the central nervous system.
I. Techniques for Isolation of Venoms
In order to avoid impurities within the spider venom and the isolated toxins, the spider venom which was used for the tests described below was electrically milked from the spiders using a method which employs safeguards to prevent contamination of the venom by abdominal regurgitate or hemolymph.
Once the spider venom is obtained by electrical milking techniques, it is further purified using gel filtration chromatography or other similar related techniques. In addition, it is frequently desirable for final fractionation of the spider venom to be performed by high performance liquid chromatography ("HPLC").
Thus, using the technique of electrically milking the spider coupled with gel filtration chromatography and high performance liquid chromatography it is possible to obtain purified and usable spider toxins. It will be appreciated, however, that other equivalent techniques may also be employed the spider toxins used.
II. Specific Toxin within the Scope of the Invention
While it will be appreciated that additional toxins may also fall within the scope of the present invention, the following relates to the identification and isolation of a specific toxin which has been found to have the characteristics required for a usable calcium channel blocker as described above. In addition, the native gene responsible for the production of the toxin has been identified.
Using the techniques described above relating to the collection of venom, a toxin has been isolated from the Agelenopsis aperta spider having a molecular weight of approximately 5274 and the peptide sequence described herein. It has been found that AG1 blocks synaptic transmission in in vitro preparations of chick cochlear nucleus and rat hippocampus.
In experiments performed using the toxin, it has been found that the toxin is very potent in that 100 nanomolar concentrations produce half-maximol blockade of synaptic transmission in rat hippocampus slices and 1 micromolar concentrations produce complete blockade.
Complete blockade using AG1 on central nervous system cells occurs in the absence of presynaptic action potentials and the time course of action is unaffected by the rate of presynaptic stimulation. Partial blocks achieved by brief exposure to dilute AG1 toxin were stable for at least one hour and were unaffected by increases or decreases in stimulation rate. Partial blockade by AG1 however, can be largely reversed by increasing the extracellular calcium concentration. Subsequent reduction in calcium concentration, however, causes the postsynaptic response to decline to its previous level of partial blockade.
In the absence of toxin, the same increase in calcium has no effect on the amplitude of responses. These results indicate that this toxin acts on calcium channels to produce long lasting blockade of transmission. The effects are independent of stimulation frequency, suggesting that the toxin does not act primarily on synthesis or reuptake of transmitter. Calcium antagonism of the effects makes it improbable that the toxin causes massive release of transmitter.
In summary, it is found that this toxin is antagonized by increasing calcium concentrations and produces blockade of synaptic transmission in cochlear chick nucleus and rat hippocampus without affecting axonal conduction. In addition, this toxin has been found not to be acutely toxic and does not affect the electrical excitability of cochlear nucleus neurons themselves, indicating that its effects are not produced by acute cytotoxic action.
III. Comparison with other Calcium Channel Blockers
Receptor- and voltage-activated calcium channels are of fundamental importance in the survival and function of virtually all cell types. Entry of calcium through such channels regulates a variety of cellular activities including contraction of cardiovascular muscle and the release of neurotransmitters from nerve cells. There are presently three major known classes of organic calcium channel blockers, as opposed to inorganic blockers such as manganese or lanthanum. These organic calcium channel blockers include: phenylalkylamines such as verapamil; benzothiazepines such as diltiazem; and dihydropyridines such as nifedipine.
The currently available organic calcium channel blockers have pronounced actions on heart and vascular smooth muscle, although relative selectivity for these two types of tissues varies among these compounds. A second notable feature of these agents is that, although they will bind to brain tissue, they have either no effect or a relatively minor effect on the function of neurons in the central nervous system, particularly as compared to their striking effects on heart and vascular smooth muscle.
The AG1 toxin derived from Agelenopsis aperta venom has properties that very clearly distinguish it from the currently available calcium channel blockers. AG1 acts primarily, if not exclusively, on neuronal calcium channels as opposed to heart or vascular smooth muscle calcium channels. This tissue selectivity is opposite to that seen in the compounds mentioned above.
Because of the importance of calcium and calcium channels to the function of neurons, there are a variety of potential applications of compounds within the scope of the present invention. Calcium influx through channels mediates neurotransmitter release and modulates neuronal excitability. Selective blockers of neuronal calcium channels, therefore, could modify neuronal excitability by effects on both presynaptic and postsynaptic calcium channels.
Accordingly, appropriate calcium channel blockers could be used in treatment of several neurological disorders that are thought to involve excessive neuronal excitation: e.g., stroke, traumatic head injury, epilepsy, and neurodegenerative disorders such as Huntington's disease and Alzheimer's disease.
IV. Amino Acid Sequencing
AG1 was further analyzed in order to determine its amino acid sequence. Initially, venom was obtained from Agelenopsis aperta spiders using the techniques described herein. Active fractions of the venom were pooled and subjected to separation by ion-exchange chromatography. The fraction of the venom constituting the AG1 toxin was then isolated using the techniques described herein, including in Example 2. The AG1 toxin was then analyzed by employing known techniques and with the aid of a mechanical amino acid analyzer.
The results of the amino acid sequence analyses of AG1 yielded a 48 amino acid peptide. The peptide has a molecular weight in the range of from approximately 5272 to approximately 5282 daltons. The sequence of the peptide as identified by the procedure set forth above is as follows: ##STR2##
V. Identification of the Gene Responsible for Production of AG1
Employing the amino acid sequence data obtained as described above, the gene responsible for the production of AG1 was isolated and identified.
Initially, the possible codons responsible for each amino acid in the sequenced peptide were identified and plotted. Table 1 lists the possible codons which relate to each amino acid in the peptide. It will be appreciated that the possible number of sequences available to produce the peptide is very large, due to the fact that some of the amino acids can be produced by up to six (6) different nucleotide sequences. When it is appreciated that a 48 amino acid peptide is involved, with most of the amino acids possibly being encoded by multiple nucleotide sequences, it will be appreciated that sequential testing using possible oligonucleotide probes was found to be impractical.
TABLE 1 AG1 IN ALL CODONS. 5 10 15 20 GLU ASP ASN CYS ILE ALA GLU ASP TYR GLY LYS CYS THR TRP GLY GLY THR LYS CYS CYS GAA GAC AAC TGT ATT GCT GAA GAC TAC GGT AAG TGT ACT TGG GGT GGT ACT AAG TGT TGT GAG GAT AAT TGC ATC GCC GAG GAT TAT GGC AAA TGC ACC GGC GGC ACC AAA TGC TGC ATA GCG GGA ACA GGA GGA ACA GCA GGG ACG GGG GGG ACG 25 30 35 40 ARG GLY ARG PRO CYS ARG CYS SER MET ILE GLY THR ASN CYS GLU CYS THR PRO ARG LEU AGA GGT AGA CCA TGT AGA TGT TCT ATG ATT GGT ACT AAC TGT GAA TGT ACT CCA AGA TTG GGC CCT TGC TGC TCC ATC GGC ACC AAT TGC GAG TGC ACC CCT CTA AGG GGA AGG CCG AGG TCA ATA GGA ACA ACA CCG AGG TTA CGT GGG CGT CCC CGT TCG GGG ACG ACG CCC CGT CTG CGC CGC CGC AGT CGC CTT CGA CGA CGA AGC CGA CTC CGG CGG CGG CGC 45 50 55 60 ILE MET GLU GLY LEU SER PHE ALA ATT ATG GAA GGT TTG TCT TTC GCT ATC GAG GGC CTA TCC TTT GCC ATA GGA TTA TCA GCG GGG CTG TCG GCA CTT AGT CTC AGC
Accordingly, a technique employing PCR was developed and is illustrated schematically in FIG. 1. PCR is well documented in the literature, including the citations set forth above. Essentially PCR allows the production of a selected DNA sequence when the two terminal portions of the sequence are known. Primers, or oligonucleotide probes, are obtained which correspond to each end of the sequence of interest. Using PCR, the central portion of the DNA sequence is then synthetically produced.
In sequencing the gene corresponding to AG1, a first primer was selected which corresponds to the poly (A) terminus, also sometimes referred to herein as a d(T) tailed primer. The d(T) tailed primer also includes a restriction site downstream from the d(T) segment. In this particular procedure a NotI restriction site was included (CGCGGCCGC). The d(T) tailed primer is illustrated at 1 in step (a) of FIG. 1, and the mRNA of the spider is illustrated at 2. All mRNA is then reverse transcribed to cDNA using the d(T) tailed primer as is represented graphically by the arrow in step (a).
The synthetic cDNA is then denatured and annealed as is shown in step (b). At this point an appropriate NH2 primer or oligonucleotide is synthesized. See, Table 2. In the synthesis of the primer the data of Table 1 is employed to determine the possible sequences which may be usable. In addition, in order to select the sequences which are most likely to result in the actual sequence, preference data of the type illustrated in Table 3 is employed.
At this point, the primer 3 is bound to the denatured cDNA and a cDNA sequence is produced as illustrated at step (c) in FIG. 1 Because the primer is specific to the desired mRNA sequence, only the cDNA which corresponds to the chosen sequence will be effectively amplified.
The resulting material is amplified over multiple cycles, as is taught in PCR procedure as is shown at step (d). In this particular case amplification took place over 39 cycles in order to assure maximum amplification.
The result of the process is a synthetic cDNA sequence which corresponds to that of the gene of interest. This is illustrated at (e). The DNA produced is then digested with the appropriate restriction enzymes and cleaved at the engineered restriction site. (Cleaving the restriction site enables it to be cloned). This step is illustrated at (f).
TABLE 2__________________________________________________________________________Primers for PCR amplification of AG1 Gene Sequnces AA #: 1 2 3 4 5 6 7 8__________________________________________________________________________Amino acid: E D N C I A E DAll possible codons: GAG GAC AAC TGT ATT GCA GAG GA GAA GAT AAT TGC ATC GCC GAA ATA GCG GCTNH--K Oligo: GAG GAC AAC TGC ATT GCA GAG GA GAT AAT ATC GCC GAA GCG GCT__________________________________________________________________________
TABLE 3__________________________________________________________________________ Drosophila Preference (1)A.A. # of codons Favored codons h = high bias gene l = low bias gene Human Preference(2)__________________________________________________________________________C 2 UGC h = 0.97 l = 0.65 0.70D 2 GAC h = 0.61 l = 0.22 0.62E 2 GAG h = 0.91 l = 0.64 0.60F 2 UUC h = 0.94 l = 0.57 0.65H 2 CAC h = 0.86 l = 0.57 0.58K 2 AAG h = 0.97 l = 0.60 0.55N 2 AAC h = 0.94 l = 0.44 0.66Q 2 CAG h = 0.99 l = 0.56 0.74Y 2 UAC h = 0.89 l = 0.52 0.53I 2 AUC h = 0.75 l = 0.32 0.64 AUU h = 1.00 l = 0.74 0.87A 4 GCC h = 0.94 l = 0.71 0.71 GCUG 4 GGC h = 0.75 l = 0.64 0.59 GGUP 4 CCC h = 0.84 l = 0.52 0.65 CCAT 4 ACC h = 0.76 l = 0.40 0.47 ACG h = 0.81 l = 0.63 0.59V 4 GUC h = 0.85 l = 0.68 0.77 GUGL 6 CUG h = 0.71 l = 0.34 0.46 CUC h = 0.83 l = 0.49 0.68R 6 CGC h = 0.95 l = 0.37 0.28 CGUS 6 UCC h = 0.65 l = 0.45 0.33 UCG AGC h = 0.84 l = 0.62 0.62__________________________________________________________________________ (1)Sharp, P. et al., Nucl. Acids Res. 16, 8207 (1988). (2)Lathe, R. J. Mol. Biol. 183, 1 (1985).
Finally, the produced cDNA sequence can be cloned into an appropriate vector using conventional techniques, analyzed and sequenced. The DNA sequence is presented in Table 4. A direct amino acid translation of this anchored PCR product revealed that it corresponded to the complete coding sequence for AG1, as well as all DNA sequences preceding the poly (A) tail. See, Table 5. The exact function and purpose of the portion of the gene between the stop codon for the peptide and the beginning of the poly (A) tail is not known at this time.
The complete sequence is set forth in Table 4. Table 4 shows the DNA sequence above the corresponding peptide for each of the 48 peptides. Table 4 also sets forth the DNA sequence between the end of the material useful for encoding the peptide and the beginning of the poly (A) tail, as well as the tail itself. Additional detail concerning the procedure described above is included herein in Example 3.
FIG. 2 illustrates the results of Southern analysis of one-tenth of the reaction products. "A" is an autoradiograph of an ethidium stained gel of one-tenth of the reaction products obtained from the amplification of 25 ng mRNA using the amino primer d(T) tailed primer adapter. The size marker lane was Hinf I digested φ174 DNA. "B" is the results of Southern analysis of the reaction products confirmed by probing with an internal gene sequence. The results show dramatically the effectiveness of the technique described above.
TABLE 4__________________________________________________________________________Translated SequenceSequence Range: 1 to 317 ##STR3## ##STR4## ##STR5## ##STR6## ##STR7## ##STR8## ##STR9##ATTTCTAGAGTTCGTCTTATCGCTACCTCGTCTTGTAGATCAAATGAATGT ##STR10##TAATATAATTATAATATAATTTATTAGGAGTTTATTCCTACATATTAAAAC ##STR11##ACTACTTTAATTTTTAAGAAATAAGCGTTTTTTTTT TTTTTTTTTTTTTTT ##STR12##TTTTTTTTTTT__________________________________________________________________________
TABLE 5______________________________________peptideK AA Composition DataCalculated Molecular Weight = 5280.729Estimated pI = 6.465Amio Acid Composition: Number Percent______________________________________Non-polar:Ala 2 4.17Val 0 0.00Leu 2 4.17Ile 3 6.25Pro 2 4.17Met 2 4.17Phe 1 2.08Trp 1 2.08Polar:Gly 6 12.50Ser 2 4.17Thr 4 8.33Cys 8 16.67Tyr 1 2.08Asn 2 4.17Gln 0 0.00Acidic:Asp 2 4.17Glu 4 8.33Basic:Lys 2 4.17Arg 4 8.33Bis 0 0.00______________________________________
Recombinant Expression
Provision of a suitable DNA sequence encoding the desired protein permits the production of the protein using recombinant techniques now well known in the art. The coding sequence can be obtained by retrieving a cDNA or genomic sequence from a native source of the protein or can be prepared synthetically using the accurate amino acid sequence from the nucleotide sequence of the gene. When the coding DNA is prepared synthetically, advantage can be taken of known codon preferences of the intended host.
Expression systems containing the requisite control sequences, such as, promoters, and preferably enhancers and termination controls, are readily available and known in the art for a variety of hosts.
Thus, the desired proteins can be prepared in both procaryotic and eucaryotic systems, resulting, in the case of many proteins, in a spectrum of processed forms. The most commonly used procaryotic system remains E. coli, although other systems such as B. subtillis and Pseudomonas could also be used. Suitable control sequences for procaryotic systems include both constitutive and inducible promoters including the lac promoter, the trp promoter, hybrid promoters such as tac promoter, and the lambda phage P 1 promoter. In general, foreign proteins may be produced in these hosts either as fusion or mature proteins; when the desired sequences are produced as mature proteins, the sequence produced may be preceded by a methionine which is not necessarily efficiently removed. Accordingly, the peptides and proteins claimed herein may be preceded by an N-terminal Met when produced in bacteria. Moreover, constructs may be made wherein the coding sequence for the peptide is preceded by an operable signal peptide which results in the secretion of the protein. When produced in procaryotic hosts in this matter, the signal sequence is removed upon secretion.
A wide variety of eucaryotic hosts is also now available for production of recombinant foreign proteins. As in bacteria, eucaryotic hosts may be transformed with expression systems which produce the desired protein directly, but more commonly signal sequences are provided to effect the secretion of the protein. Eucaryotic systems have the additional advantage that they are able to process introns which may occur in the genomic sequences encoding proteins of higher organisms. Eucaryotic systems also provide a variety of processing mechanisms which result in, for example, glycosylation, oxidation or derivatization of certain amino acid residues, conformational control, and so forth.
Commonly used eucaryotic systems include yeast, insect cells, mammalian cells, avian cells, and cells of higher plants. The list is not exhaustive. Suitable promoters are available which are compatible and operable for use in each of these host types as well as are termination sequences and enhancers. As above, promoters can be either constitutive or inducible. For example, in mammalian systems, the MTII promoter can be induced by the addition of heavy metal ions.
The particulars for the construction of expression systems suitable for desired hosts are well known to those in the art. For recombinant production of the protein, the DNA encoding it is suitably ligated into the expression system of choice, and the system is then transformed into the compatible host which is then cultured and maintained under conditions wherein expression of the included gene takes place. The protein thus produced is recovered from the culture, either by lysing the cells or from the culture medium as appropriate.
A "mutation" in a protein alters its primary structure (relative to the commonly occurring or specifically described protein) due to changes in the nucleotide sequence of the DNA which encodes it. These mutations specifically include allelic variants. Mutational changes in the primary structure of a protein result from deletions, additions, or substitutions. Such changes involving only 3 or less amino acid residues are generally preferred. A "deletion" is defined as a polypeptide in which one or more internal amino acid residues are absent. An "addition" is defined as a polypeptide which has one or more additional internal amino acid residues as compared to the wild type. A "substitution" results from the replacement of one or more amino acid residues by other residues. A protein "fragment" is a polypeptide consisting of a primary amino acid sequence which is identical to a portion of the primary sequence of the protein to which the polypeptide is related.
Preferred "substitutions" are those which are conservative, i.e., wherein a residue is replaced by another of the same general type. As is well understood, naturally-occurring amino acids can be subclassified as acidic, basic, neutral and polar, or neutral and nonpolar. Furthermore, three of the encoded amino acids are aromatic. It is generally preferred that encoded peptides differing from the native form contain substituted codons for amino acids which are from the same group as that of the amino acid replaced.
Thus, in general, the basic amino acid Lys, Arg, and His are interchangeable; the acidic amino acids aspartic and glutamic are interchangeable; the neutral polar amino acids Ser, Thr, Cys, Gln, and Asn are interchangeable; the nonpolar aliphatic acids Gly, Ala, Val, Ils, and Leu are conservative with respect to each other (but because of size, Gly and Ala are more closely related and Val, Ile and Leu are more closely related), and the aromatic amino acids Phs, Trp, and Tyr are interchangeable.
While proline is a nonpolar neutral amino acid, it represents difficulties because of its effects on conformation, and substitutions by or for proline are not preferred, except when the same or similar conformational results can be obtained. Polar amino acids which represent conservative changes include Ser, Thr, Gln, Asn; and to a lesser extent, Met. In addition, although classified in different categories, Ala, Gly, and Ser seem to be interchangeable, and Cys additionally fits into this group, or may be classified with the polar neutral amino acids. Some substitutions by codons for amino acids from different classes may also be useful.
Because recombinant materials for the proteins of the invention are provided, these proteins can be made recombinantly. Because of the variety of post-translational characteristics conferred by various host cells, various modifications for the naturally-occurring proteins will also be obtained. A "modified" protein differs from the commonly occurring protein as a result of post-translational events which change the glycosylation or lapidation pattern, or the primary, secondary, or tertiary structure of the protein.
It should be further noted that if the proteins herein, such as AG1, are made synthetically, substitutions by amino acids which are not encoded by the gene may also be made. Alternative residues include, for example, the ωamino acids of the formula H 2 N(CH 2 ) n COOH wherein n is 2-6. These are neutral, nonpolar amino acids, as are sarcosine (Sar), t-butylalanine (t-BuA), t-butylglycine (t-BuG), N-methyl Ila (N-MeIle), and norleucine (Nle). Phenylglycine, for example, can substituted for Trp, Tyr or Phe an aromatic neutral amino acid; citrulline (Cit) and methionine sulfoxide (MSO) are polar but neutral, cyclohexyl alanine (Cha) is neutral and nonpolar, cysteic acid (Cya) is acidic, and ornithine (Orn) is basic. The conformation conferring properties of the proline residues may be obtained if one or more of these is substituted by hydroxyproline (Hyp).
V. EXAMPLES
The following examples are given to illustrate particular compositions and methods within the scope of the present invention but they are not intended to limit the scope of the present invention.
EXAMPLE 1
A spider toxin within the scope of the present invention was isolated from the Agelenopsis aperta spider. Spider venom was obtained from, and species identification provided by, Spider Pharm, Inc. of Black Canyon City, Ariz. and Natural Product Sciences, Inc., Salt Lake City, Utah. Agelenopsis aperta spiders were electrically milked using a method that employs safeguards to prevent contamination of venom by abdominal regurgitate or hemolymph. Venom was diluted 1 to 10 with avian Tyrode solution (140 mM NaCl, 4 mM KCl, 4 mM NaHCO 3 , 1 mM MgSO 4 , 3 mM CaCl, 1.2 mM NaH 2 PO 4 , 10 mM HEPES, 10 mM glucose) and fractionated by gel filtration using Bio-Gel P-10 and a 0.7×30 cm column and collected in 0.5 ml fractions. These fractions were assayed for blockade of synaptic below.
HPLC separation of active gel filtration fractions was performed using a Vydac C-18 reverse phase column. Components were eluted from the column over a period of 60 minutes using a 0-60% linear gradient of 60% acetonitrile in 0.1% trifluoroacetic acid. Elution was monitored by absorbance detection at 214 nm. Peaks were collected manually, dried down, stored at -20° C., and then reconstituted with avian Tyrode before use.
For gel electrophoresis, a 15 ul sample of each gel filtration fraction was mixed with 7.5 ul of 3X sample buffer (18% 1M tris-HCL, pH 6.8, 15% 2 mercaptoethanol, 30% glycerol, 7% sodium dodecyl-sulfate, 0.001% bromphenol blue) and the entire sample was loaded onto a 10% to 20% gradient polyacrylamide gel using the slab method. Electrophoresis was performed at 20 watts constant power for three hours. Gels were stained with Coomassie blue.
The toxin so isolated had a molecular weight of approximately 6,000 as estimated from SDS polyacrylamide gels as was designated AG1. The toxin was bath-applied to cochlear nucleus neurons in an in vitro preparation of chick brain stem. Upon stimulation of the cochlear nerve innervating the cochlear nucleus, it was found that the toxin blocked transmission between the cochlear nerve afferents and the cochlear nucleus neurons.
EXAMPLE 2
Agelenopsis aperta spiders were electrically milked using a method that employs safeguards to prevent contamination of venom by abdominal regurgitate or hemolymph. Venom was diluted to 1 to 10 with avian Tyrode solution and fractionated by gel filtration using Bio-Gel P-10 and a 0.7×30 cm column and collected in 0.5 ml fractions. These fractions were assayed for blockage of synaptic transmission using an in vitro preparation of the chick cochlear nucleus. Active fractions (fractions 7-9) were pooled and subjected to separation by ion-exchange chromatography using NaCl concentrations of 10-300 mM, 0.5 ml fractions were again collected and assayed. A fraction eluting in 70 mM NaCl contained the material active in blocking synaptic transmission in the chick cochlear nucleus. This fraction was then subjected to separation by high-performance liquid chromatography (HPLC) using a Vydac C-18 reverse-phase column. Components were eluted from the column over a period of 60 minutes using a 0-60% linear gradient of 60% acetonitrile in 0.1% trifluorooacetic acid. Elution was monitored by absorbance detection at 214 nm. Peaks were collected manually, dried down, stored at -20° C. and then reconstituted in avian Tyrode solution before being re-assayed on the chick cochlear nucleus preparation. A single major peak in the chromatogram appeared to contain most of the activity in the AG1 fraction; this peak was subjected to amino acid composition and sequence analyses using the following methods.
Samples of AG1 were subjected to amino acid analysis by known techniques. The samples were hydrolyzed in vacuo with 6N HCL, at 105° C. for 24 hours. Acid Was removed by drying in a Speed-Vac and the residue was analyzed by ion-exchange chromatography on a Beckman Model 121 amino acid analyzer. Other samples of AG1 were reduced, carboxymethylated, and analyzed in a Beckman 890D spinning cup peptide sequencer using a 0.1M Quadrol program. Polybrene carrier was precycled by running four steps in the presence of 100 nmol of Ser-Gly. PTH-amino acids were analyzed by HPLC using methods described by Gray et al. (J. Biol. Chem. 256:4734-4740, 1981).
The results of amino acid and sequence analyses of AG1 yielded the following 48-amino acid peptide: ##STR13##
EXAMPLE 3
The coding gene for AG1 from Agelenopsis was isolated. The procedure for isolating the gene is outlined as follows:
1 Isolate RNA from spider; purify mRNA.
2. Synthesize oligonucleotide primer corresponding to the amino-terminal protein sequence data and internal primer if data available.
3. Reverse transcribe the RNA using a d(T) primer carrying an engineered restriction site.
4. PCR amplify the coding sequence and any downstream sequences preceding the poly (A) tail using amino-specific and d(T) primers.
5. Analyze PCR amplified products (verify with internal probe if available). Isolate product.
6. Digest with appropriate enzymes, clone and sequence.
Step #1:
Spiders were collected and identified at Natural Product Sciences, Inc., Salt Lake City, Utah as Agelenopsis aperta. Venom glands were pulled from anesthetized spiders and quickly frozen in liquid nitrogen. RNA was extracted from the venom glands using the protocol of Chomczynski and Sacchi (Analytical Biochemistry 162, 156 (1987)). Polyadenylated messenger RNA (nRNA) was purified using oligo d(T) cellulose (Pharmacia LKB, Sweden) chromatography.
Step #2:
An oligonucleotide corresponding to residues 1 through 8 of the peptide K amino acid sequence was designed using some Drosophila codon preferences to reduce degeneracy. The cDNA synthesis (antisense) primer was composed of a run of 15 deoxythymidine residues adjacent to a Not I restriction enzyme site. An internal oligonucleotide probe was synthesized to represent amino acid sequence 10 to 16 with all possible preferences. The sense primer and internal primer were synthesized at the University of Utah, Howard Hughes Medical Institute contract facility. The d(T) Not I primer was purchased from Promega (Madison, Wis.).
Step #3: cDNA synthesis
Messenger RNA was reverse transcribed to cDNA with murine leukemia virus reverse transcriptase (Bethesda Research Laboratories, Maryland) using the manufacturer's protocol. The 20 ul reaction mixture contained the enzyme buffer as supplied in a cDNA synthesis kit (Boehringer Mannheim, Indiana), 50 ng of mRNA, 2 units of RNase H, 30 ng of d(T)Not I primer, 1 mM each deoxynucleoside triphosphates, and 100 u of reverse transcriptase. The reaction mixture was incubated for 1 h at 37° C. and continued for 10 minutes at 42° C. The reaction mixture was ethanol precipitated and resuspended in 20 ul H 2 O.
Step #4: Amplification
Primer directed enzymatic amplification of DNA with a thermostable DNA polymerase was initially described by Saiki, et. al. (Science, 239:487 (1988)). For our application, 10 ul of the venom gland cDNA was used as template in a polymerase chain reaction containing reagents contained in the GeneAmp™ DNA amplification kit (Perkin Elmer Cetus, California). The amplification reaction contained the sense and antisense primers in a 2 uM concentration, 100 uM of each deoxynucleotide triphosphate, and 4 units of the thermostable recombinant Taq polymerase. The reaction was run in a programmable heat block manufactured by Coy Laboratories (Ann Arbor, Mich.). It was started by denaturing the RNA-cDNA hybrid at 95° C. for 2 minutes, annealing the primers for 2 minutes at 37° C., and then extending the primers at 72° C. for 1 minute. This cycle was repeated twice and the program then switched to an identical profile incorporating an elevated annealing temperature of 54° C. This cycle was repeated 35 times. After the final cycle, the samples were chilled at 5° C.
Step #5:
One-tenth of the reaction mixture was run on a composite gel containing 3% NuSieve/1% SeaKem agaroses (FMC, Rockland, Me.) in Tris/borate/EDTA (TBE) buffer in the presence of ethidium bromide The gel was photographed and transferred onto Biotrace™ nylon membrane (Gelman Sciences, Ann Arbor, Mich.) using an alkaline transfer protocol (E. M. Southern, J Mol Biol 98:503 (1975) and Reed and Mann, NAR 13:7277 (1985)). The membrane was prehybridized for 12 h at 42° C. in 5X SSC (0.75M NaCl/0.075M sodium citrate pH 7.0,) 20 mM sodium phosphate, pH 6.7, 2X Denhardt's (Sigma), and 0.1 mg/ml E. Coli tRNA (Boehringer Mannheim). To the buffer was then added 2×10 5 cpm/ml of 5' end 32 p labeled internal probe. Hybridization was continued at 42° C. for 24 h, and washing was done at 56° C. with 5X SSC/. The blot was autoradiographed using Kodak XAR film at -70° C. for 1 hour.
Step #6:
The anchored PCR product visualized in FIG. 2 was purified through a Centricon-100 (Amicon) to remove unincorporated primers. The insert was then digested with the restriction enzyme Not I (MBR, Milwaukee, Wis.), utilizing the restriction site contained in the downstream primer. The vector, pKS (Statagene, LaJolla, Calif.), was double digested with EcoR V (U.S. Biochemical) and Not I to generate sites specific for directional cloning. Vector and insert were ligated and transformed into competent E.coli strain DH5α. Colony lifts were screened with the 32 P labeled internal probe and candidate colonies were further characterized by sequencing (U.S. Biochemical's Sequenase Version 2.0) mini-prep DNA using the internal probe as primer.
The inserts of three gene-containing candidates were then sequenced in entirety using commercially available external primers The sequence of one of the clones, pKS-KK, is presented in Table 4. The entire coding sequence as well as the 135 bp region preceding the poly (A) tail account for 282 base pairs of the sequence for the AG1 gene. Analysis of the translated peptide sequence suggested a protein of MW 5,280.73 daltons with 8 cysteine residues as shown in Table 5. If the cysteines are involved in disulfide bridges this suggests a molecular weight of 5,272.73 daltons which is in agreement with the mass spectroscopy data.
EXAMPLE 4
The high molecular weight Agelenopsis aperta toxin described in Example 1 was obtained using the same procedure as described in Example 1. Gel-filtration fractions having the effects described in Example 1 were diluted 1:150 with Tyrode and bath-applied for one minute to an in vitro preparation of the chick brain stem. This brief exposure to dilute toxin produced partial (about 50%) blockade of transmission.
These partial blocks were stable for at least one hour and were unaffected by increases or decreases in the rate of cochlear nerve stimulation over a range of 0-30 Hz. Partial blockade, however, was largely reversed by increasing extracellular calcium from 3 to 9 mM. Subsequent reduction of extracellular calcium back to 3 mM caused the postsynaptic response to revert to its previous level of partial blockade.
The result so obtained indicates that this toxin acts to produce long-lasting blockade of transmission. The finding that the effects of this toxin are independent of stimulation frequency suggests that the toxin does not act primarily on synthesis or reuptake of transmitter. The inverse relationship between extracellular calcium concentration and the blocking effects of the toxin indicates that the toxin likely acts on calcium channels. This action could be exerted on presynaptic calcium channels necessary for the release of transmitter and/or on postsynaptic calcium channels involved in the response of the cochlear nucleus neurons to synaptic stimulation.
EXAMPLE 5
The toxin AG1 described in Examples 1 through 4 is obtained in the manner described above from Agelenopsis aperta spider venom.
The toxin so obtained is applied and a complete blockade of synaptic transmission is achieved as described in Example 1. EAA agonists quisqualic acid and kainic acid are then individually bath-applied to the cochlear nucleus neurons at concentrations of 5 mM and 50 uM, respectively.
Application of these agonists at such concentrations normally reduces the ability of cochlear nucleus neurons to respond to direct electrical stimulation, presumably by depolarizing them by an action on EAA receptors. When applied in the presence of AG1 toxin the same effect is seen; that is, after 10 minutes of application of either quisqualic of kainic acids in the presence of AG1 toxin the response of cochlear nucleus neurons to direct antidromic stimulation is reduced by about 75%. The degree and time-course of this effect are not significantly different from those observed when either quisqualic of kainic acid is applied in the absence of AG1 toxin.
The result so obtained indicates that this toxin does not exert its blocking effects on synaptic transmission by a direct action on EAA receptors on the postsynaptic neuron but rather by a direct action of the toxin on calcium channels as suggested in Examples 1 and 3. If it were acting directly on EAA receptors it would be expected that the toxin would also block the effects of directly applied EAA agonists, such as quisqualic or kainic acid. The obtained result runs counter to that expectation.
EXAMPLE 6
The high molecular weight toxin described in Examples 1 through 5 (AG1) is obtained in the manner described above from Agelenopsis aperta spider venom.
The toxin so obtained is applied for the purpose of labeling calcium channels in neurons or other cell types. A radioactive label (such as 125 I) is incorporated in the toxin molecule. Binding of the labeled toxin is then assayed using autoradiography of tissue sections or quantification (using scintillation counting) of binding to various tissue extracts such as synaptosomal or membrane preparations. Autoradiography of brain tissue sections labeled with the radioactive toxin reveals the regional distribution of the calcium channels to which the toxin binds. (A similar result is obtained by observing the binding pattern of the toxin conjugated to a fluorescent label.) The binding of the toxins to tissue extracts under various conditions, such as the presence of other drugs, provides information regarding the pharmacology of the calcium channel to which the toxin binds.
EXAMPLE 7
The AG1 toxin described in Examples 1-6 above is obtained in the manner described above from Agelenopsis aperta spider venom.
The toxin so obtained is tested for its ability to block synaptic transmission in an in vitro brain slice preparation of the rat hippocampus following generally the procedures described by Mueller et al. ("Noradrenergic responses in rat hippocampus: Evidence for mediation by alpha and beta receptors in the in vitro slice." Brain Research 214:113-126, 1981). When dissolved in the artificial cerebral spinal fluid bathing the hippocampal slice, the toxin shows a concentration-dependent ability (over the range from 1 nM to 1 μM) to inhibit the population spike (PS) recorded extracellularly from the CA1 region of the hippocampus with microelectrodes. In repeated experiments, the toxin is shown to produce half-maximal inhibition of the PS at a concentration of approximately 100 nanomolar. At concentrations that completely inhibit the PS, this toxin has no effect on axonal conduction, as reflected in the unchanged "afferent volley" component of the measured response. The magnitude of the PS suppression produced by this toxin is reduced as extracellular calcium concentration is increased from 2.4 mM (control) to 7.5 mM and 10 mM.
IV. SUMMARY
It will be appreciated that the present invention provides the ability to effectively block specific channels using the toxin. Similarly, specific channel blockers with activity on the central nervous system may have the potential to treat various neurological disorders. It has been found, for example, that these channel blockers may act as a treatment of epilepsy. In addition, channel blockers of the type disclosed in the present invention may also be used in treatments of stroke, traumatic head injury, and degenerative central nervous system diseases such as Huntington's disease.
In summary, it can be seen that the methods and compositions of the above invention accomplish the objectives set forth above. In particular, the present invention provides calcium channel blockers which can be used as research tools or in a clinical setting. In particular, the spider toxins of the present invention can be used as calcium channel blockers in the central nervous system.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
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Methods and compositions for blocking Ca 2+ channels within an organism are provided. For example, a toxin was isolated from the Agelenopsis aperta spider. The toxin comprised a 48 amino acid toxin having a molecular weight of approximately 5,274. This toxin was found to block calcium channels within the central nervous system. The Agelenopsis gene responsible for producing this toxin has been identified and cloned. This gene and/or its derivatives provide a mechanism by which the toxin can be produced using recombinant DNA expression technologies.
The present invention further relates to methods of treating neurological diseases by applying the toxins isolated and identified. The toxin may provide beneficial effects on certain neurological conditions including seizures, ischemic-hypoxic CNS damage, and neurodegenerative disorders. It is also found that the toxins are effective as tags in probing calcium channels.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a national stage application, filed under 35 U.S.C. §371, of International Application No. PCT/US2008/056403, filed on Mar. 10, 2008, which claims the benefit of and priority to U.S. Patent Application Ser. No. 60/900,558, filed Feb. 8, 2007, the disclosure of each is incorporated by reference herein.
Each of the applications and patents cited in this text, as well as each document or reference cited in each of the applications and patents (including during the prosecution of each issued patent; “application cited docutments”), and each of the U.S. and foreign applications or patents corresponding to and/or claiming priority from any of these applications and patents, and each of the documents cited or referenced in each of the application cited documents, are hereby expressly incorporated herein by reference. More generally, documents or references are cited in this text, either in a Reference List before the claims, or in the text itself; and, each of these documents or references (“herein-cited references”), as well as each document or reference cited in each of the herein-cited references (including any manufacturer's specifications, instructions, etc.), is hereby expressly incorporated herein by reference. Documents incorporated by reference into this text may be employed in practice of the invention.
RELATED APPLICATIONS
This application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 60/893,736, filed Mar. 8, 2007; which is hereby incorporated by reference in its entirety.
GOVERNMENT SUPPORT
This invention was made with support from the National Institutes of Health, NCI/NASA UIP, NIH NIDDK, NSF and DARPA-MTO; therefore, the government has certain rights in the invention.
BACKGROUND OF THE INVENTION
Mammalian cells in vivo integrate and respond to cues in their microenvironment that vary in both time and space. In particular, interactions between neighboring cells can regulate both the fate and function of individual cells as well as govern the emergent properties of the resultant tissue. Because such cell-cell interactions occur primarily through direct contact or exchange of soluble factors, understanding the temporal and spatial aspects of these signals is of fundamental importance to tissue biology. Recent advances in cell ‘micropatterning’ have already proven invaluable in increasing our understanding of the structure-function relationships of such multicellular communities (El-Ali, J., Sorger, P. K. & Jensen, K. F. (2006) Nature 442, 403-11; Bhatia, S. N., Balis, U. J., Yarmush, M. L. & Toner, M. (1999) Faseb J 13, 1883-900; Nelson, C. M., Jean, R. P., Tan, J. L., Liu, W. F., Sniadecki, N. J., Spector, A. A. & Chen, C. S. (2005) Proc Natl Acad Sci USA 102, 11594-9; and Liu, W. F., Nelson, C. M., Pirone, D. M. & Chen, C. S. (2006) J. Cell Biol. 173, 431-441). However, dynamic manipulation of tissue structure in vitro has remained largely out of reach.
Previous efforts towards spatio-temporal control of tissue organization at the cellular scale have focused on modulation of the adhesive properties of the culture substrate (Okano, T., Yamada, N., Okuhara, M., Sakai, H. & Sakurai, Y. (1995) Biomaterials 16, 297-303; Lahann, J., Mitragotri, S., Tran, T. N., Kaido, H., Sundaram, J., Choi, I. S., Hoffer, S., Somorjai, G. A. & Langer, R. (2003) Science 299, 371-4; and Jiang, X., Ferrigno, R., Mrksich, M. & Whitesides, G. M. (2003) J Am Chem Soc 125, 2366-7.). Through the micropatterning of surface chemistries that can be dynamically altered, localized attachment and release of cells has been demonstrated (Cheng, X. H., Wang, Y. B., Hanein, Y., Bohringer, K. F. & Ratner, B. D. (2004) Journal of Biomedical Materials Research Part A 70A, 159-168; and Yeo, W. S., Yousaf, M. N. & Mrksich, M. (2003) J Am Chem Soc 125, 14994-5). Nonetheless, these manipulations are typically not reversible (i.e., nonadhesive surfaces are rendered adhesive just once), they do not allow the decoupling of processes associated with adhesion from those correlated with cell-cell interaction (i.e., attachment, spreading, and contact with neighboring cells have overlapping time scales), nor can these platforms accommodate serial manipulations to mimic key biological events (i.e., sequential exposure of a target cell population to different inducer populations). Manipulations of surface chemistry are also limited by the inability to precisely control tissue composition: sequential seeding of different cell types can result in contamination of pure populations and maintaining micron-scale proximity of two cell populations in the absence of contact over many days—important for decoupling the relative role of contact and paracrine signals—has not been achieved.
SUMMARY OF THE INVENTION
The development and function of living tissues depends largely on interactions between cells that can vary in both time and space; however, temporal control of cell-cell interaction is experimentally challenging. By employing a micromachined substrate with moving parts, herein is disclosed the dynamic regulation of cell-cell interactions via direct manipulation of adherent cells with micron-scale precision. The inventive devices and methods allow mechanical control of both tissue composition and spatial organization. The inventive device and methods enable the investigation of dynamic cell-cell interaction in a multitude of applications, such as intercellular communication, spanning embryogenesis, homeostasis, and pathogenic processes.
In one specific embodiment, the utility of the inventive devices and methods in deconstructing the dynamics of intercellular communication between hepatocytes and supportive stromal cells in co-culture is demonstrated. Specifically, the findings disclosed herein indicate that the maintenance of the hepatocellular phenotype by stroma requires direct contact for a limited time (on the order of hours) followed by a sustained soluble signal which has an effective range of less than about 400 μm.
In another embodiment, use of the inventive devices and methods to characterize the microenvironmental regulation of sinusoidal endothelial cell phenotypes is demonstrated. Specifically, disclosed are novel microenvironmental regulators of the liver sinusoidal endothelial cells (LSEC) phenotype, which may be important for the development of better in vitro models of liver disease.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 depicts micromechanical substrates which enable micrometer-resolution cell positioning. (A) Microfabricated silicon parts can be fully separated (left), or locked together with comb fingers in contact (middle) or slightly separated (right). Cells are cultured on the top surfaces; manual scraping can be used to restrict cells to the comb fingers only (inset). The slope of the tapered comb fingers results in a 20:1 mechanical transmission ratio; that is, sliding the parts 1.6 mm changes the gap between the fingers by only 80 μm. Together with the integrated snap-lock mechanism, it is thereby possible to control separation with repeatable micrometer-scale precision using unassisted manual actuation. (B and C) Brightfield images of hepatocytes (darker cells) and 3T3 fibroblasts cultured on the comb fingers. The silicon is first functionalized by spin-coating with polystyrene followed by plasma treatment, resulting in a surface comparable to tissue culture plastic. Devices can be reused multiple times (>20). (D) Devices in a standard 12-well plate. Cell culture and functional assays are performed using standard methods. Actuation is also performed directly on the plate using sterile tweezers. (E) One embodiment of micromechanical substrates which enable micrometer-resolution cell positioning.
FIG. 2 depicts the results of reconfigurable cell culture studies. Cultures can be reversibly switched to initiate or to eliminate contact between two cell populations; individual populations can also be removed and replaced. (A) Fluorescent images illustrating possible device manipulations. Each cell type was pre-labeled with an individual dye color. (B) Fluorescent image showing intimate contact between hepatocytes (green) and stroma (red, 3T3 fibroblasts) at the interface between neighboring comb fingers. Image was taken 18 h following initiation of contact. Cell nuclei counterstained in blue. (C) Cross-migration of cells is minimal for moderate durations of contact. Representative fluorescent image showing small numbers of stromal cells (red, arrows indicate selected cells) remaining behind on a hepatocyte finger (green) after combs were separated following 18 h of contact. In this work, contact was limited to 18 h in order to minimize cross-migration, but longer durations are possible with other cell types (data not shown).
FIG. 3 depicts results of dynamic regulation of hepatocyte-stromal interactions, which reveals temporal dependencies in intercellular communication. (A) Contact between hepatocyte and fibroblast combs was required to maintain albumin secretion over a 2-wk period (red). In the gap mode (blue), function dropped almost as rapidly as with hepatocytes alone (green). (B) An 18-h period of transient initial contact followed by long-term culture in the gap mode (which allows diffusion of paracrine signals) resulted in sustained liver-specific function (blue) similar to that obtained with sustained contact (red). However, 18 h of initial contact followed by removal of adjacent stroma resulted in deterioration of function (green). (C) Following 18 h of initial contact, stroma were removed and replaced by nave stroma (in gap mode). Liver-specific function was maintained at similar levels (blue) to that obtained with no cell swapping (red). In a parallel experiment in which nave hepatocytes were substituted, liver-specific function was not maintained (green).
FIG. 4 depicts results which show the use of spatial reconfiguration to reveal short-range soluble signaling. (A) Following 18 h of initial contact, hepatocytes and stroma were separated into individual wells. Stromal conditioned media was transferred every 2 days to the hepatocytes, but liver-specific function declined (blue). In contrast, transient contact followed by microscale separation (using the gap mode) resulted in sustained function (red). (B) Loss in liverspecific function progresses to loss in hepatocyte viability. Hepatocyte viability was probed using a membrane integrity dye (calcein AM, green) with a nuclear counterstain for both cell types (blue). Following initial contact, cultures were maintained for two weeks in the gap mode, resulting in a sharp gradient in hepatocyte viability dependent on proximity to stroma (n>3, representative image shown). Selected comb fingers are outlined in white for clarity. (C) Quantified calcein fluorescence along the length of a comb finger (n=9). L, the characteristic decay length of viability, is measured to be 325 μm using an exponential fit over x>0.
FIG. 5 depicts one proposed model for intercellular communication. Maintenance of liver-specific function in hepatocytes requires (1) an initial short-term (τ is about 18 h) contact-mediated signal from stromal cells, followed by (2) sustained short-range (L is about 325 μm) soluble signaling from the stroma.
FIG. 6 depicts results demonstrating that micromechanical substrates can be generalized to other cell types and biological techniques. (A) Bipotential mouse embryonic liver progenitor cells cultured for 1 day on a micromechanical substrate. The BMEL cell line, 9A1, was provided by Dr. Mary Weiss (Institut Pasteur) and cultured as described previously (Strick-Marchand, H., Morosan, S., Charneau, P., Kremsdorf, D. & Weiss, M. C. (2004) Proc Natl Acad Sci USA 101, 8360-5; and Strick-Marchand, H. & Weiss, M. C. (2002) Hepatology 36, 794-804). In brief, cells were cultured on collagen in RPMI 1640 medium with glutamax (Invitrogen, Carlsbad, Calif.), containing 30 ng/mL human IGF-II (Peprotech, Rocky Hill, N.J.), 50 ng/mL human EGF (Peprotech), and 10 mg/mL recombinant human insulin (Invitrogen). (B) Primary rat liver sinusoidal endothelial cells (LSEC) cultured for 1 day on a collagen-coated micromechanical substrate. Briefly, LSEC were isolated from the nonparenchymal fraction of the liver through a 25%/50% Percoll gradient (Zhang, B., Borderie, D., Sogni, P., Soubrane, O., Houssin, D. & Calmus, Y. (1997) J Hepatol 26, 1348-55) and cultured in the presence of VEGF (R&D Systems, Minneapolis, Minn.). (C) OP9 bone marrow stromal cells (ATCC, Manassas, Va.) cultured for 1 day on a collagen-coated micromechanical substrate, using alpha minimum essential medium without ribonucleosides and deoxyribonucleosides with 2 mM L-glutamine and 1.5 g/L sodium bicarbonate, 80%; fetal bovine serum, 20% (all from Invitrogen). (D) Cells can be transfected with siRNA while adhered to micromechanical substrates, allowing selective delivery using the separated mode. Fluorescent image of Swiss 3T3 fibroblasts transfected with siRNA sequence (against Lamin A) with FITC fluorophore conjugated to 5′ end of sense strand (Dharmacon, Lafayette, Colo.). Transfection was performed using Lipofectamine 2000 (Invitrogen) on cells adhered to the substrate.
FIG. 7 depicts intermediates in one approach to device fabrication.
FIGS. 8 a and 8 b depict a table of Selected Immune Cytokines and Their Activities. Key: CTL: cytotoxic T lymphocytes; DC: dendritic cells; GM-CSF: Granulocyte-Monocyte Colony Stimulating Factor; IL: interleukin; IFN: Interferon; TGF: Tumor Growth Factor; TNF: Tumor Necrosis Factor. Note that “*” indicates that italicized activities are inhibited.
FIG. 9 depicts data showing that LSEC lose their differentiated phenotype when cultured ex vivo. (A) Specifically, there is a strong decrease in the LSEC-specific marker SE-1 and an increase in the non-specific endothelial marker PECAM-1, comparing cells at 1 day versus 3 days of culture. There is no significant change in RECA observed. (B) In vivo, SE-1 is shown to mark the cells in the sinusoidal vascular endothelium, the site of the LSEC. PECAM-1 is shown to mark cells in larger diameter blood vessels, the site of vascular endothelial cells.
FIG. 10 depicts data showing that LSEC, when in co-culture with supportive cell types, can maintain their differentiated phenotype (expression of SE-1) for up to 14 days. The optimum maintenance is obtained in the case where LSEC are cultured with both hepatocytes and 3T3 fibroblasts together. This is demonstrated by immunofluorescence (top) as well as by Western Blot (bottom). Direct cell-cell contact did not appear to be necessary for maintenance of SE-1 expression (bottom). (Top) Use of the micromechanical substrates enables organization of the cell types to facilitate identification during microscopy. (Bottom) Use of the micromechanical substrates enables LSEC to be separated from the support cells prior to Western Blot analysis, resulting in a clean measurement from a purified cell population.
FIG. 11 depicts data showing LSEC proliferation as a function of various supportive cell types in co-culture. Maximum proliferation is obtained in co-culture with hepatocytes (either alone or together with 3T3 fibroblasts). Proliferation is measured via incorporation of BrdU.
FIG. 12 depicts examples of molds for casting polymer replicas of the microfabricated silicon parts. (A) PDMS mold cast from one embodiment of a comb component of the invention. (B) Silicon wafer parts from which device elements have been cut are reassembled on a PDMS base to form a cavity in which replica parts may be cast.
FIG. 13 depicts population-specific readout or selective interrogation. Hepatocytes and 3T3 fibroblasts are co-cultured to maintain hepatocyte differentiation. In (A) the drug Pyrilamine is introduced while the cells are in co-culture. By using the micromechanical substrates, the two cell populations are separated prior to viability assay, allowing the viability of each cell type to be assessed independently. The 3T3 are shown to be more sensitive to the toxic effects of Pyrilamine. In (B) the effect of the drug Methapyrilamine is compared when the cells are in co-culture or when the 3T3 are alone. The 3T3 are shown to be more sensitive to the toxic effects of the drug when alone.
FIG. 14 depicts the dynamic responses of intracellular signaling kinases within hepatocytes during the first 120 minutes in response to the introduction of 3T3 cells in co-culture. By using the micromechanical substrates, hepatocytes are brought into contact with 3T3 fibroblasts for a short, defined period of time and then separated back to a pure hepatocyte population prior to cell lysis. The phosphorylation of various kinases was then measured using a cytometeric bead array.
DETAILED DESCRIPTION OF THE INVENTION
Overview. Cellular behavior within tissues is driven by environmental cues that vary temporally and spatially with a granularity on the order of individual cells. Local cell-cell interactions via secreted and contact-mediated signals play a critical role in these pathways. In order to study these dynamic small-scale processes, herein is disclosed a micromechanical platform to control microscale cell organization so that cell patterns can be reconfigured dynamically. In one embodiment, this tool has been employed to deconstruct the mechanisms by which liver-specific function is maintained in hepatocytes upon co-cultivation with stromal support cells. Specifically, the relative roles of cell contact and short-range soluble signals, duration of contact, and the possibility of bi-directional signaling were examined. In another embodiment, this tool has been used to investigated microenvironmental regulation of the sinusoidal endothelial cell phenotype.
In certain embodiments, the inventive device consists of two parts that can be locked together either to allow cell-cell contact across the two parts or to separate the cells by a uniform gap. Switching between these two states is actuated simply by pushing the parts manually using tweezers; no micromanipulation machinery is necessary. Micron-scale precision is possible due to a 20:1 mechanical transmission ratio and microfabricated snap locks, both of which are monolithically incorporated into the silicon structure. In certain embodiments, the entire device is fabricated in a simple single-mask process using through-wafer deep reactive ion etching. In certain embodiments, to provide a surface compatible with cell culture, the surface is coated with a layer of polystyrene and plasma-treated, providing a standard tissue-culture surface. In other embodiments, the device is fabricated from silicon. In other embodiments, the device is fabricated from polyurethane. In certain embodiments, the parts can be anchored to a frame while being etched, and then released with a dicing saw or the like.
Herein are disclosed devices and methods designed to enable one precisely to control tissue organization and composition by leveraging tools from the field of microelectromechanical systems (MEMS), which offers precise physical manipulation at a length scale comparable to that of many biological processes. In certain embodiments, cells are grown on an array of micromachined plates that are physically rearranged in order to change the spatial organization of the culture. This will be referred to as micromechanical reconfigurable culture (μRC). Cells remain attached to the substrate throughout the repositioning process (Chen, C. S., Mrksich, M., Huang, S., Whitesides, G. M. & Ingber, D. E. (1997) Science 276, 1425-1428; and McBeath, R., Pirone, D. M., Nelson, C. M., Bhadriraju, K. & Chen, C. S. (2004) Dev Cell 6, 483-95). Using μRC, dynamic regulation of cell-cell interactions via direct manipulation of cell positioning has been demonstrated. Specifically, cell-cell contact between different cell populations was regulated by positioning plates together or apart. By imposing a small micron-scale separation between the plates, cell-cell contact can be abrogated while soluble signaling is maintained. By employing larger separation distances, the extent of soluble signaling can also be modulated. In addition, by removing a plate and replacing it, one population of cells can be exchanged for another in a modular fashion. Thus, this MEMS-based approach provides dynamic control of both tissue organization and composition.
Micromechanical Reconfigurable Culture Devices (μRC). In certain embodiments, the micromechanical reconfigurable culture devices of the invention consist of two or more components that can be moved with respect to each other. In certain embodiments, the devices of the invention are a single piece, parts of which can be moved with respect to each other. In certain embodiments, the components of the device are shaped as flat plates or curved surfaces.
In certain embodiments, the components of the device can be mounted on a positioning system which allows their position, relative to each other, to be varied. In another embodiment, in order to connect the two (or more) component, one or more flexures may be used. As used herein, a “flexure” is a flexible mechanical member used to connect two separate components. A properly designed flexure is extremely stiff in every direction except the direction of motion. In certain embodiments, the flexures of the invention may be used as a hinge to guide the linear motion of two or more of the components.
In certain embodiments, at least one of the components of the device will have two substantially-parallel arm flexures protruding from the main body of the component. In certain embodiments, these arm flexures each include a distal catch (or latch) with corresponds to slot (or notch) on a separate component. An example of the use of flexures in the invention is the integrated snap-lock mechanism shown in FIG. 1E . As shown in FIG. 1E , in certain embodiments, the matching V-shaped latches and notches are self-centering, allowing the parts to be accurately and reproducibly positioned using only tweezers, without the need for microscopic visualization or micromanipulation machinery. In certain embodiments, the extent of finger separation in the gap mode can be tuned via notch positioning; multiple sets of notches could also be employed to allow variable spacing.
In certain embodiments, the snap-lock mechanism can consist of more than one set of snaps and slots, giving multiple points of constraint (e.g., leading to greater stability). In certain embodiments, there are two snaps and two sets of locks.
Further, the alignment of components of the invention may be facilitated by features on one component which fit into features of another component, thereby constraining the mechanical positioning of the components. For example, in certain embodiments, these features are implemented as teeth in a comb pattern. In certain embodiments, the contacting surfaces are angled with respect to the direction of motion so that the changes in separation between parts is less than the total amount of motion. In such embodiments, finer positioning accuracy can be obtained, particularly when using coarse actualization methods, such as manual pushing.
In certain embodiments, the μRC device consists of two components with interlocking comb fingers and an integrated snap-lock mechanism (as discussed above). The components can be fully separated, locked together with the fingers in contact, or locked together with a fixed gap between the comb fingers ( FIG. 1A ). These configurations are referred to as the separated, contact, and gap modes. Cells are cultured on the top surface of the fingers ( FIGS. 1B and 1C ). In certain embodiments, each the fingers of each component can contain one type of cell, wherein the cells on the first component are not the same as the cells on the second component. In other words, each component has a “pure” population of cells. In other embodiments, the cells cultured on any given finger can be a mixed population of more than one cell type.
In certain embodiments, parts can be separated into individual wells of a multi-well plate for coating of extracellular matrix proteins and seeding of cells, so as to avoid cross-contamination. Following cell attachment, the two parts can be assembled in a fresh well ( FIG. 1D ), where cell culture and functional assays can be performed in a standard manner. The actuation strategy to switch between modes was designed for simplicity and compatibility with standard aseptic cell-culture technique.
In certain embodiments, the entire μRC device is fabricated in a simple single-mask process using through-wafer deep reactive ion etching (see intermediates of this process in FIG. 7 ). See, for example: Ayon, A. A., Braff, R., Lin, C. C., Sawin, H. H. & Schmidt, M. A. (1999) Journal of the Electrochemical Society 146, 339-349; and Knobloch, A. J., Wasilik, M., Fernandez-Pello, C. & Pisano, A. P. (2003) in 2003 ASME International Mechanical Engineering Congress (American Society of Mechanical Engineers, New York, N.Y. 10016-5990, United States, Washington, D.C., United States), Vol. 5, pp. 115-123. In certain embodiments, a silicon wafer can be coated with a micrometer thick layer of silicon dioxide. After which, a layer of thick photoresist can be spin-coated onto the coated silicon wafer, patterned using a chrome mask and contact alignment, and developed. The patterned wafer, or device wafer, can then be attached to a handle wafer using a photoresist bond. After etching through the oxide layer, deep reactive ion etching can be used to etch through the entire device wafer. The parts can then be released in acetone and cleaned in “Piranha” (chromic acid-containing) solution.
As mentioned above, to provide the necessary mechanical precision, silicon parts can be fabricated in a single mask, through-wafer, deep reactive ion etching process. In the exemplification provided herein, a separation of 6 μm or less was measured in the contact mode, and 79±1 μm in the gap mode. Using fluorescent membrane dyes and microscopy, cells on opposing fingers were shown to form intimate contacts in contact mode ( FIG. 2B ). In addition, contamination of cells between adjacent fingers after 18 hours of contact was minimal ( FIG. 2C ).
In certain embodiments, the silicon parts of the μRC device are modified to aid in the culture of different cell types. In certain embodiment, the silicon parts of the device spincoated with polystyrene, resulting in a surface comparable to tissue culture plastic. This can aid, for example, in the binding of fibroblasts; poor adhesion was of fibroblast cells on unmodified silicon surfaces has been observed (data not shown). In certain embodiments, collagen is adsorbed onto the silicon parts of the device. This can aid, for example, in the binding of hepatocytes.
In certain embodiments, the inventive μRC device could include embedded microfluidics and sensors for local delivery of soluble factors and in situ monitoring (Papageorgiou, D. P., Shore, S. E., Bledsoe Jr, S. C. & Wise, K. D. (2006) Journal of Microelectromechanical Systems 15, 1025-1033), and/or integrated actuation for heterogeneous mechanical control of array elements.
In certain embodiments, the μRC device is fabricated from an optically transparent material. In certain embodiments, the μRC device is fabricated from an optically translucent material. Transparent and translucent μRC devices could be used with inverted biological microscopes. As used herein, transparent materials can be seen through; that is, they allow clear images to pass. Translucent materials allow light to pass through them only diffusely, that is, the material distorts the image. In certain embodiments, the μRC device is fabricated from an optically transparent or optically translucent material selected from the group consisting of glasses and plastics.
In certain embodiments, the μRC device comprises more than two interlocking pieces. In certain embodiments, the μRC device comprises more three interlocking pieces. In certain embodiments, the μRC device comprises four interlocking pieces. In certain embodiments, the μRC device comprises more than four interlocking pieces.
Developmental Biology: Stem Cells/Morphogens. Cell-cell interactions play a critical role in driving differentiation during development. Stem cells are defined as cells that are capable of a differentiation into many other differentiated cell types. Embryonic stem cells are stem cells from embryos which are capable of differentiation into most, if not all, of the differentiated cell types of a mature body. Stem cells are referred to as pluripotent, which describes this capability of differentiating into many cell types. A category of pluripotent stem cell of high interest to the research community is the human embryonic stem cell, abbreviated here as hES cell, which is an embryonic stem cell derived from a human embryonic source. Human embryonic stem cells are of great scientific interest because they are capable of indefinite proliferation in culture and are thus capable, at least in principle, of supplying cells and tissues for replacement of failing or defective human tissue. The existence in culture of human embryonic stem cells offers the potential of unlimited amounts of human cells and tissues for use in a variety of therapeutic protocols to assist in human health. In the future human embryonic stem cells may be proliferated and directed to differentiate into specific lineages so as to develop differentiated cells or tissues which can be transplanted into human bodies for therapeutic purposes.
One of most significant features of human embryonic stem cells is the attribute of being capable of self-renewal. By that, it is meant that the hES cells are capable of proliferating into multiple progeny stem cells, each of which seems to have the full potential of its ancestor cell. In other words, the progeny are renewed to have all the developmental and proliferative capacity of the parental cell. This attribute, combined with the pluripotency, are the traits that make hES cells candidates for many potential uses, since, in theory, hES cells can be reproduced indefinitely and in large numbers and then induced to become any cell type in the human body. The ability to self-renew appears closely linked to the attribute of being undifferentiated in the sense that at least given present knowledge, only undifferentiated hES cells are capable of indefinite self-renewal; i.e., as soon as the cells differentiate, the self-renewal capability is lost.
During the course of development, cells of many tissues differentiate according to the positional information that is set by the concentration gradients of morphogens. Morphogens are signaling molecules that emanate from a restricted region of a tissue and spread away from their source to form a concentration gradient. As the fate of each cell in the field depends on the concentration of the morphogen signal, the gradient prefigures the pattern of development. Thus, micromechanical reconfigurable culture (μRC) is an ideal way to study morphogens and the cells they effect (e.g., stem cells).
As described above, a morphogen is a substance governing the pattern of tissue development and, in particular, the positions of the various specialized cell types within a tissue. It spreads from a localized source and forms a concentration gradient across a developing tissue. Well-known morphogens include: Decapentaplegic/Transforming growth factor beta, Hedgehog/Sonic Hedgehog, Wingless/Wnt, Epidermal growth factor, and Fibroblast growth factor. Morphogens are defined conceptually, not chemically, so simple chemicals such as retinoic acid may also act as morphogens.
For example, bone morphogenesis is induced by bone morphogenetic proteins (BMPs). BMPs play a role in pattern formation, cell differentiation, maintenance and regeneration of tissues. BMPs are pleiotropic and act on chemotaxis, mitosis and differentiation of progenitor stem cells. There are nearly twenty BMPs in the human genome. BMPs have actions beyond bone in development of teeth, heart, kidney, eye, skin, and brain. Thus, BMPs may be called body morphogenetic proteins. Stem cells are primordial cells with unlimited replicative potential and can be programmed by morphogens such as BMPs.
Developmental Biology: Cytokines/Cytokine Receptors. Cytokines are small secreted proteins which mediate and regulate immunity, inflammation, and hematopoiesis. They often are produced de novo in response to an immune stimulus. They generally (although not always) act over short distances and short time spans and at very low concentration. They act by binding to specific membrane receptors, which then signal the cell via second messengers, often tyrosine kinases, to alter its behavior (gene expression). Responses to cytokines include increasing or decreasing expression of membrane proteins (including cytokine receptors), proliferation, and secretion of effector molecules. Thus, micromechanical reconfigurable culture (μRC) is an ideal way to study cytokines and their receptors.
Cytokine is a general name; other names include lymphokine (cytokines made by lymphocytes), monokine (cytokines made by monocytes), chemokine (cytokines with chemotactic activities), and interleukin (cytokines made by one leukocyte and acting on other leukocytes). Cytokines may act on the cells that secrete them (autocrine action), on nearby cells (paracrine action), or in some instances on distant cells (endocrine action). As used herein, cytokine encompasses all of these.
It is common for different cell types to secrete the same cytokine or for a single cytokine to act on several different cell types (pleiotropy; see FIGS. 8 a and 8 b ). Cytokines are redundant in their activity, meaning similar functions can be stimulated by different cytokines. Cytokines are often produced in a cascade, as one cytokine stimulates its target cells to make additional cytokines. Cytokines can also act synergistically (two or more cytokines acting together) or antagonistically (cytokines causing opposing activities).
Their short half life, low plasma concentrations, pleiotropy, and redundancy all complicated the isolation and characterization of cytokines. Searches for new cytokines is now often conducted at the DNA level, identifying genes similar to known cytokine genes. However, micromechanical reconfigurable culture (μRC) might allow an alternative way in which to identify new cytokines, as well as study the effects of known cytokines.
The largest group of cytokines stimulates immune cell proliferation and differentiation. This group includes Interleukin 1 (IL-1), which activates T cells; IL-2, which stimulates proliferation of antigen-activated T and B cells; IL-4, IL-5, and IL-6, which stimulate proliferation and differentiation of B cells; Interferon gamma (IFNg), which activates macrophages; and IL-3, IL-7 and Granulocyte Monocyte Colony-Stimulating Factor (GM-CSF), which stimulate hematopoiesis.
Other groups of cytokines include interferons and chemokines. Interferons IFNa and IFNb inhibit virus replication in infected cells, while IFNg also stimulates antigen-presenting cell MHC expression. Chemokines attract leukocytes to infection sites. Chemokines have conserved cysteine residues that allow them to be assigned to four groups. The groups, with representative chemokines, are C-C chemokines (RANTES, MCP-1, MIP-1a, and MIP-1b), C-X-C chemokines (IL-8), C chemokines (Lymphotactin), and CXXXC chemokines (Fractalkine). Some cytokines are predominantly inhibitory. For example, IL-10 and IL-13 inhibit inflammatory cytokine production by macrophages.
Helper T cells have two important functions: to stimulate cellular immunity and inflammation, and to stimulate B cells to produce antibody. Two functionally distinct subsets of T cells secrete cytokines which promote these different activities. Th1 cells produce IL-2, IFNγ, and TNFβ, which activate Tc and macrophages to stimulate cellular immunity and inflammation. Th1 cells also secrete IL-3 and GM-CSF to stimulate the bone marrow to produce more leukocytes. Th2 cells secrete IL-4, IL-5, IL-6, and IL-10, which stimulate antibody production by B cells.
T cells are initially activated as Th0 cells, which produce IL-2, IL-4 and IFNγ. The nearby cytokine environment then influences differentiation into Th1 or Th2 cells. IL-4 stimulates Th2 activity and suppresses Th1 activity, while IL-12 promotes Th1 activities. Th1 and Th2 cytokines are antagonistic in activity. Th1 cytokine IFNg inhibits proliferation of Th2 cells, while IFNγ and IL-2 stimulate B cells to secrete IgG 2a and inhibit secretion of IgG 1 and IgE. Th2 cytokine IL-10 inhibits Th1 secretion of IFNg and IL-2; it also suppresses Class II MHC expression and production of bacterial killing molecules and inflammatory cytokines by macrophages. IL-4 stimulates B cells to secrete IgE and IgG 1 . The balance between Th1 and Th2 activity may steer the immune response in the direction of cell-mediated or humoral immunity.
Cytokines act on their target cells by binding specific membrane receptors. The receptors and their corresponding cytokines have been divided into several families based on their structure and activities. Hematopoietin family receptors are dimers or trimers with conserved cysteines in their extracellular domains and a conserved Trp-Ser-X-Trp-Ser sequence. Examples are receptors for IL-2 through IL-7 and GM-CSF. Interferon family receptors have the conserved cysteine residues but not the Trp-Ser-X-Trp-Ser sequence, and include the receptors for IFNα, IFNβ, and IFNγ. Tumor Necrosis Factor family receptors have four extracellular domains; they include receptors for soluble TNFα and TNFβ as well as membrane-bound CD40 (important for B cell and macrophage activation) and Fas (which signals the cell to undergo apoptosis). Chemokine family receptors have seven transmembrane helices and interact with G protein. This family includes receptors for IL-8, MIP-1 and RANTES. Chemokine receptors CCR5 and CXCR4 are used by HIV to preferentially enter either macrophages or T cells.
Hematopoietin cytokine receptors are the best characterized. They generally have two subunits, one cytokine-specific and one signal transducing. An example is the GM-CSF subfamily, where a unique a subunit specifically binds either GM-CSF, IL-3, or IL-5 with low affinity and a shared β subunit signal transducer also increases cytokine-binding affinity. Cytokine binding promotes dimerization of the α and β subunits, which then associate with cytoplasmic tyrosine kinases to phosphorylate proteins which activate mRNA transcription. GM-CSF and IL-3 act on hematopoietic stem cells and progenitor cells and activate monocytes. With IL-5, they also stimulate eosinophil proliferation and basophil degranulation. All three receptors phosphorylate the same cytoplasmic protein. Antagonistic GM-CSF and IL-3 activities can be explained by their competition for limited amounts of β subunit.
The IL-2R subfamily of receptors for IL-2, IL-4, IL-7 , IL-9, and IL-15 have a common signal-transducing g chain. Each has a unique cytokine-specific a chain. IL-2 and IL-15 are trimers, and share an IL-2R β chain. Monomeric IL-2R a has low affinity for IL-2, dimeric IL-2R bg has intermediate affinity, and trimeric IL-2R abg binds IL-2 with high affinity. IL-2R α chain (Tac) is expressed by activated but not resting T cells. Resting T cells and NK cells constitutively express low numbers of IL-2βγ. Antigen activation stimulates T cell expression of high affinity IL-2R trimers as well as secretion of IL-2, allowing autocrine stimulation of T cell proliferation in an antigen-specific manner. Antigen specificity of the immune response is also maintained by the close proximity of antigen-presenting B cells and macrophages with their helper T cells, so that cytokines are secreted in the direction of and close to the membrane of the target cell. X-linked severe combined immunodeficiency (X-scid) is caused by a defect in IL-2R family γ chain, which results in loss of activity from this family of cytokines.
Cytokine activity can be blocked by antagonists, molecules which bind cytokines or their receptors. IL-1 has a specific antagonist that blocks binding of IL-1α and IL-1β to their receptor. During immune responses, fragments of membrane receptors may be shed and then compete for cytokine binding. Microbes also influence cytokine activities. For example, Vaccinia virus (Smallpox and Cowpox) encodes soluble molecules which bind IFNγ, while Epstein-Barr virus (Infectious Mononucleosis) encodes a molecule homologous to IL-10 that suppresses immune function in the host.
The TNF receptor family molecules CD40 and Fas bind cell surface ligands on effector T cells: CD40L and FasL. CD40 is expressed on B cell and macrophage plasma membranes. T cell CD40L binding to B cell CD40 stimulates B cell proliferation and isotype switching. T cell CD40L binding to macrophage CD40 stimulates macrophages to secrete TNFa and become much more sensitive to IFNγ. T cell FasL binding to Fas leads to the activation of caspase proteases that initiate apoptosis of the cell expressing membrane Fas. Activated lymphocytes express Fas, so that FasL-positive Tc cells can regulate the immune response by eliminating activated cells. An immune deficiency disease linked to expression of a mutant Fas is characterized by over-proliferation of lymphocytes.
Cancer Biology. Interactions between a tumor and its surrounding stroma are known to play an important role in determining the progression of certain cancers. Cancers are classified by the type of cell that resembles the tumor and, therefore, the tissue presumed to be the origin of the tumor. The following general categories are usually accepted: carcinoma, lymphomas, leukemias, sarcomas, mesotheliomas, gliomas, germinomas, and choriocarcinomas. Carcinomas are malignant tumors derived from epithelial cells. This group represent the most common cancers, including the common forms of breast, prostate, lung and colon cancer. Lymphomas and leukemias are malignant tumors derived from blood and bone marrow cells. Sarcomas are malignant tumors derived from connective tissue, or mesenchymal cells. Mesotheliomas are tumors derived from the mesothelial cells lining the peritoneum and the pleura. Gliomas are tumors derived from glia, the most common type of brain cell. Germinomas are tumors derived from germ cells, normally found in the testicle and ovary. Choriocarcinomas are malignant tumors derived from the placenta.
RNAi. In certain embodiments of the invention, RNA interference (RNAi) techniques can be used in conjunction with method which employ the micromechanical reconfigurable culture devices of the invention. RNAi is a technique widely used to down-regulate the mRNA level of a specific gene. Small interfering RNAs (siRNAs) or small hairpin RNAs (shRNAs) are composed of a 22 nt-double strand RNA sequence completely homologous to an unique target gene. ShRNAs are generally produced by RNA polymerase II or III-based vectors while siRNA can be obtained from biotechnology companies. The siRNA or shRNA-expressing vectors are transfected into cell lines with classical lipotransfectants. The homology of sequence with a specific target gene allows formation of a complex comprising one strand of the shRNA or siRNA hybridized with the mRNA target and the RISC (RNAi-induced silencing complex) proteins in the cytoplasm. RISC then degrades the mRNA, which cannot be translated. The whole process leads to the specific downregulation of the RNA of the corresponding gene within 24-72 hours.
Microenvironmental Regulation of Sinusoidal Endothelial Cell Phenotypes. Liver Sinusoidal Endothelial Cells (LSEC) are distinct from other vascular endothelial cells (EC) present in other tissues in their structural and functional phenotypic characteristics. For example, in contrast to other EC, LSEC display fenestrations, have low or absent expression of PECAM-1, and in rat tissue, they distinctively express the specific surface marker SE-1. Interestingly, these phenotypic characteristics are lost over time when LSEC are placed in culture. Since phenotypic maintenance is critical to the development of accurate in vitro liver models and tissue engineered constructs, by using the devices and methods described herein the one can examine effect of various microenvironmental stimuli, such as tailoring of the extracellular matrix (ECM) and co-culture with supportive cell types, on LSEC phenotype.
For example, immunohistochemistry and Western blotting were used to characterize expression of the specific EC markers RECA, SE-1, PECAM and AcLDL in isolated primary rat LSECs were cultured under the following conditions: a) on the different ECM proteins including, Collagen-I, Fibronectin, Laminin, and Collagen-IV; b) with various combinations of supportive cells, using the micromechanical reconfigurable culture method described herein to enable tracking of individual cell types, separation into pure populations for analysis, and deconvolution of contact-mediated versus soluble signals; and c) in the presence of the tyrosine phosphatase inhibitor, orthovanadate (OV). Results of these studies are shown in FIGS. 9, 10 and 11 .
Interestingly, using the methods described above, a decrease in the expression of SE-1 and increase expression of PECAM-1 was observed when LSEC were placed in culture; in addition, an effect of specific ECM components on the levels of expression of SE-1 was also observed, suggesting a role of ECM in modulating LSEC phenotype. Significantly, SE-1 expression could be maintained for longer periods through co-culture—up to 14 days in the optimal configuration involving co-cultivation with both hepatocytes and fibroblasts. The data also suggest that direct contact between LSECs and support cells is not necessary. To begin to gain a mechanistic insight into these observations, the role of tyrosine phosphorylation of cellular proteins in maintaining LSEC phenotype was investigated, since it has previously demonstrated that OV inhibited LSEC apoptosis (Fujimoto, H. et al. (2006) Am J Pathol 168, 1086-1096). It was found that SE-1 expression was strongly maintaining at day 3 when they were cultured in the presence of OV, suggesting that a decrease in protein phosphorylation is involved also in the loss of the phenotype. In addition, the co-culture of LSEC with hepatocytes or fibroblast-stabilized hepatocytes induced LSEC proliferation as well as the activation of the transcription factor STAT-1.
Collectively, the experiments described above led to the identification of novel microenvironmental regulators of the LSEC phenotype, which may be important for the development of better in vitro models the study of liver biology and tissue engineering constructs.
Selected Applications. In one embodiment, the inventive dynamic platform disclosed herein was used to study cell-cell interactions between hepatocytes and stromal cells in co-culture. As with many other cell types, interaction of epithelia with supportive stroma or ‘feeder layers’ promotes tissue-specific gene expression in vitro. In the case of primary hepatocytes, co-cultivation of hepatocytes with many different mesenchymal cell types (endothelia, fibroblasts, etc.) promotes retention of hepatocyte viability and liver-specific functions that are otherwise rapidly lost in vitro (Bhatia, S. N., Balis, U. J., Yarmush, M. L. & Toner, M. (1999) Faseb J 13, 1883-900). This robust ‘co-culture’ phenomena, though poorly understood, has wide-ranging applications in both therapeutic and diagnostic applications of engineered liver tissue (Tilles, A. W., Baskaran, H., Roy, P., Yarmush, M. L. & Toner, M. (2001) Biotechnol Bioeng 73, 379-89; Allen, J. W., Khetani, S. R. & Bhatia, S. N. (2005) Toxicol Sci 84, 110-9; and Guillouzo, A. (1998) Environ Health Perspect 106 Suppl 2, 511-32). Using both conventional techniques and micropatterning approaches, it has previously been found that the degree of interaction between the two cell types (‘heterotypic interaction’) modulated the amount of liver-specific function retained in vitro (Bhatia, S. N., Balis, U. J., Yarmush, M. L. & Toner, M. (1999) Faseb J 13, 1883-900; and Guguen-Guillouzo, C. & Guillouzo, A. (1983) Mol Cell Biochem 53-54, 35-56). These findings suggested an important role for proximity between the two cell types in the rescue of hepatocyte phenotype; however, the relative role of contact-mediated versus soluble signals, the dynamics of interaction, and the potential for reciprocal signaling had not been established.
Hence, in order to explore this system using the μRC substrates, primary rat hepatocytes and Swiss 3T3 murine fibroblasts were cultured on opposing combs. Hepatocyte morphology and viability were assessed microscopically and albumin production was measured as a quantitative marker of liver-specific function. Comparison of cultures in the contact, gap, and separated modes demonstrated that contact was necessary for maintenance of liver-specific function ( FIG. 3A ). Even in the gap mode, which corresponded to only an 80-μm separation between the two cell populations, hepatocyte function declined at a rate similar to that of hepatocytes cultured alone. Next, dynamic experiments in which cells were repositioned following 18 h of contact were conducted. Here, transient contact alone proved insufficient to rescue the hepatocyte phenotype, and liver-specific functions rapidly declined. In contrast, transient contact followed by sustained culture in the gap mode provided complete rescue of liver-specific function ( FIG. 3B ). These observations thus imply a necessary role both for heterotypic contact and for soluble factors that diffuse across the gap.
Notably, it would appear that contact was required only initially, whereas soluble interactions were required for the duration of the experiment. This finding raised the possibility that reciprocal interactions—i.e., sustained alterations in fibroblast function as a result of hepatocyte contact—might play a role. In order to test this possibility, the ‘modular’ nature of the μRC platform was explored. Co-cultures were conducted in contact mode for 18 h as before; however, the fibroblasts were then replaced with naíve fibroblasts (no exposure to heterotypic contact) in gap mode. Under these conditions, paracrine signals provided by naíve fibroblasts were still sufficient to sustain hepatic functions ( FIG. 3C ). Conversely, if naíve hepatocytes were substituted, hepatic function deteriorated. Hence, the data are consistent with constitutive expression of critical soluble factors by fibroblasts independent of hepatocyte interaction rather than supporting a role for reciprocal cell-cell interaction.
To investigate the importance of cell proximity, device pairs were separated into separate wells following 18 h of initial contact. Conditioned media was then transferred from the fibroblast well to the hepatocyte well every two days. However, hepatic function was not maintained ( FIG. 4A ), underscoring the importance of close positioning in the gap configuration. Further, microscopic examination of co-cultures yielded a striking observation: in cultures stabilized via transient contact followed by gap mode, hepatocytes towards the rear of each comb finger lost viability over the course of two weeks ( FIG. 4B ). Hepatocyte-fibroblast distance is greater in this region compared to the rest of the comb finger due to the geometry of the device in the gap configuration ( FIG. 1A , inset). Quantifying viability using a fluorescent membrane integrity dye yielded a characteristic length of decay in viability of approximately 325 μm ( FIG. 4C ). It was demonstrated through finite element modeling that diffusion of a rapidly decaying (on the order of hours) or rapidly consumed (comparable to rate of production) soluble factor could produce concentration profiles similar to the survival pattern of FIG. 4B (FEM Diffusion Model). These data suggest that the fibroblast-derived soluble signals critical for rescue of the hepatocyte phenotype and viability are effective over a very limited range, on the order of only 10 cell diameters.
Preservation of hepatocyte viability and liver-specific functions in co-culture appears to depend on an initial contact-mediated signal followed by a sustained short-range soluble signal from fibroblasts to hepatocytes ( FIG. 5 ). It is not clear whether the contact-mediated signal is junctional in nature (hepatocytes and 3T3 fibroblasts do not express similar cadherin or connexin subtypes) or due to cell-associated matrix molecules. It is also unknown why only transient contact is required. One possibility is that transient contact triggers an irreversible signaling pathway. Alternatively, the contaminating cells that remain after separation ( FIG. 2C ) may play a role in the response. This seems unlikely since hepatic function could not be maintained in gap mode without initial contact, even when low numbers of fibroblasts were doped onto the hepatocyte fingers (data not shown). A third possibility is that fibroblasts secrete critical extracellular matrix components onto the hepatocyte fingers during the transient contact period that help to sustain function thereafter. Regardless, these data point to the possibility that hepatocytes could be preconditioned and subsequently sustained without supportive stromal cells, a finding with significant practical implications for the therapeutic and diagnostic applications of hepatocytes. Notably, only the peripheral hepatocytes can directly contact fibroblasts, yet the entire population is affected. This finding is consistent with previous reports but the precise mechanism has not yet been established Finally, the possible reasons that soluble signals are effective over very limited distances include: that the critical factors are highly labile, are active at relatively high local concentration, or are rapidly sequestered extracellularly via binding to extracellular matrix proteins.
As the example above suggests, μRC may be utilized to execute a number of previously inaccessible experiments. The disclosure herein establishes that it is possible to decouple contact-mediated and soluble signals, dynamically modulate both contact-mediated and soluble cell-cell signaling, examine the reversibility of a pathway upon removal of the triggering signal, test for the presence of reciprocal cell-cell signaling, and measure the effective range of soluble signals. In other words, the disclosure herein establishes that micromechanical culture substrates are a robust and generalizable tool. Since, in certain embodiments, the device surface is comparable to tissue culture plastic, it should be readily adapted to a variety of cell types and molecular techniques.
For example, compatibility with liver progenitors, sinusoidal endothelial cells, and bone marrow stromal cells, as well as transfection of siRNA into individual cell populations has been demonstrated ( FIG. 6 ). This methodology will find utility in the investigation of cellular niches (Moore, K. A. & Lemischka, I. R. (2006) Science 311, 1880-1885), in the dissection of developmental processes (Lemaigre, F. & Zaret, K. S. (2004) Curr Opin Genet Dev 14, 582-90), and in the study of disease progression—in particular in tissues where stromal interactions are thought to play a role (e.g., tumorigenesis; Zigrino, P., Loffek, S. & Mauch, C. (2005) Biochimie 87, 321-328).
Selected Methods of the Invention. The following methods illustrate different aspects and embodiments of the present invention, and are not intended to limit the scope of the invention.
One aspect of the invention relates to a method comprising the steps of culturing at least one cell of a first type on a first component; culturing at least one cell of a second type on a second component; and placing the first component at a distance from or in contact with the second component for a time; thereby co-culturing the at least one cell of a first type and the at least one cell of a second type.
As discussed above, cell-cell interactions play a critical role in driving cell differentiation during development. The reconfigurable substrates of the invention could be used to simulate these processes in vitro. For example, stem cells or progenitor cells can be driven down a specific differentiation pathway by bringing them into contact with a series of different cell types. Therefore, one aspect of the invention relates to a method of stimulating cell differentiation comprising the steps of:
culturing a plurality of cells of a first type on a first component, wherein the cells of a first type are stem cells or progenitor cells;
culturing a plurality of cells of a second type on a second component, wherein the cells of a second type secrete a differentiation-inducing signal; and
placing the first component at a distance from or in contact with the second component for a time.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, further comprising the step of determining if the cells of a first type have differentiated.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are early embryonic stem cells, blastocyst embryonic stem cells, fetal stem cells, umbilical cord stem cells, or adult stem cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are adult stem cells isolated from nerve cells, blood cells, muscle cells, skin cells, or bone cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human embryonic stem cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete morphogens.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete morphogens selected from the group consisting of decapentaplegic/transforming growth factor beta, hedgehog/sonic hedgehog, wingless/wnt, epidermal growth factor, and fibroblast growth factor.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete morphogens selected from the group consisting of human OP-1, mouse OP-1, human OP-2, mouse OP-2, 60A, GDF-1, BMP2A, BMP2B, DPP, Vgl, Vgr-1, BMP3, BMP5, and BMP6.
Further, the effects of soluble factors on any cell type, not just stem-cells, may be studied using the devices of the invention. Therefore, another aspect of the invention relates to a method of exposing cells to cytokines comprising the steps of:
culturing a plurality of cells of a first type on a first component, wherein the cells of a first type are target cells comprising a receptor;
culturing a plurality of cells of a second type on a second component, wherein the cells of a second type secrete soluble signal; and
placing the first component at a distance from or in contact with the second component for a time.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, further comprising the step of determining the effect of soluble signal exposure on the cells of a first type.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a first type comprise receptors for a member of the VEGF family, VEGF-D, a member of the MIP family, MIP-1γ, ceruloplasmin, nitric oxide, gases, or growth factors.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a first type comprise DLK, Dlk-1, a cahedrins, or T-cahedrin.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete hematopoietins, interferons, tumor necrosis factors, chemokines, or a combination thereof.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete a member of the VEGF family, VEGF-D, a member of the MIP family, MIP-1γ, ceruloplasmin, nitric oxide, gases, or growth factors
In particular, the inductive effect of cytokine gradients can be studied by varying the separation between inducer and target cell populations. Therefore, another aspect of the invention relates to a method of exposing cells to cytokines comprising the steps of:
culturing a plurality of cells of a first type on a first component, wherein the cells of a first type are target cells comprising a cytokine receptor;
culturing a plurality of cells of a second type on a second component, wherein the cells of a second type secrete a cytokine; and
placing the first component at a distance from or in contact with the second component for a time.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, further comprising the step of determining the effect of cytokine exposure on the cells of a first type.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a first type comprise cytokine receptors selected from the group consisting of hematopoietin family receptors, interferon family receptors, tumor necrosis factor family receptors, and chemokine family receptors.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a first type comprise cytokine receptors selected from the group consisting of receptors for IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-12, IL-15, GM-CSF, IFN-α, IFN-β, IFN-γ, TNF-α, TNF-β, CD40, Fas, MIP-1α, MIP-1β, RANTES, CCR5, and CXCR4.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete hematopoietins, interferons, tumor necrosis factors, chemokines, or a combination thereof.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a second type secrete IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-12, IL-15, GM-CSF, IFN-α, IFN-β, IFN-γ, TNF-α, TNF-β, CD40, Fas, MIP-1α, MIP-1β, RANTES, CCR5, or CXCR4.
Interactions between a tumor and its surrounding stroma are known to play an important role in determining the progression of certain types of cancer; reconfigurable substrates may be used to study these interactions. For example, tumor cells can be switched from co-cultivation with normal fibroblasts to cancer-associated fibroblasts using reconfigurable substrates. Dynamic changes in the biology of the tumor cells can then be measured. It follows therefore that one aspect of the invention relates to a method of exposing tumor cells to non-tumor cells comprising the steps of:
culturing a plurality of cells of a first type on a first component, wherein the cells of a first type are tumor cells;
culturing a plurality of cells of a second type on a second component; and
placing the first component at a distance from or in contact with the second component for a time.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, further comprising the step of determining changes in biology of the cells of a first type.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a first type are selected from the group consisting of tumor cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In certain embodiments, the present invention relates to the aforementioned methods and any of the attendant limitations, wherein the cells of a first type are tumor cells selected from the group consisting of carcinoma, lymphomas, leukemias, sarcomas, mesotheliomas, gliomas, germinomas, and choriocarcinomas.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are cancer-associated cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are fibroblasts.
In certain embodiments, the devices of the invention can be used for drug discovery and toxicity testing. For example, the reconfigurable substrates could be used to isolate specific secreted soluble factors, for example a factor secreted by one cell type and which has a protective or regenerative effect on another cell type. The reconfigurable substrate would be utilized to bring different cell types close together to allow soluble interaction while preventing contact interaction. RNAi techniques would then used to knockdown expression of specific soluble factors in order to isolate the critical molecules. This method is suitable for models including but not limited to liver hepatocytes co-cultivated with nonparenchymal support cells. Specifically, another aspect of the invention relates to a method of isolating a soluble factor comprising the steps of:
culturing a plurality of cells of a first type on a first component;
culturing a plurality of cells of a second type on a second component, wherein the cells of a second type secrete a soluble factor; and
placing the first component at a distance from but not in contact with the second component for a time.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, further comprising the step of using RNAi techniques to knockdown expression of the soluble factor.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, further comprising the step of determining the effect of the soluble factor on the cells of a first type.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the soluble factor has a protective or regenerative effect on the cells of a first type.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the soluble factor is selected from the group consisting of BDNF, CNTF, Dvl-1, EGF, Endostatin, FGF, GDNF, GM-CSF, Heregulin, IGF, IL, Insulin, Interferon, Jagged1, M-CSF, NAG-1, NGF, NT, PDGF, PEDF, Prolactin, SDF, SF-1, TGF, TNF, VEGF, and Wnt.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the soluble factor is selected from the group consisting of fibrinogen, laminin, collagen IV, tenascin, fibronectin, collagen, bovine pituitary extract, EGF, hepatocyte growth factor, keratinocyte growth factor, hydrocortisone, dimethyl sulphoxide, recombinant human epidermal growth factor, insulin, sodium selenite, transferrin, hydrocortisone, basic fibroblast growth factor, and leukemia inhibitory factor.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
The reconfigurable substrates if the invention could be used in organ models (including but not limited to the liver) for the screening of toxic compounds. Because cells in mixed culture can be temporarily separated into individual culture wells, compound exposure can be limited to a specific subpopulation of cells in a mixed culture model, reducing off-target effects. Also, culturing parenchymal and nonparenchymal cells in the gap configuration may yield more physiological models—cell contact is abrogated while short-range soluble interactions are preserved, which can better mimic certain in vivo physiologies.
The use of reconfigurable substrates could also be used to separate cells in mixed culture into pure populations, to facilitate clean measurements of cell behavior, whether at the RNA, protein, or organelle activity level. This would be useful, for example, in detecting toxic responses in which the metabolite of one cell population is toxic to a second cell population. Remarkably, use of reconfigurable substrates simultaneously allows both intimate cell-cell interactions (for example via short-range soluble signaling) and the ability to separate into pure populations.
It follows that one aspect of the invention relates to a method of selectively exposing a subpopulation of cells from a mixed culture of cells to a compound comprising the steps of:
culturing a mixed culture of cells comprising a plurality of cells of a first type and a plurality of cells of a second type; wherein the cells of a first type are cultured on a first component, the cells of a second type are cultured on a second component, and the first component is at a distance from or in contact with the second component;
separating the first component from the second component;
exposing the cells of a first type on the first component to a compound for a time; and
placing the first component in proximity to or in contact with the second component.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the compound is a toxic compound, exposure to which results in the death of at least some of the cells of a first type.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In another embodiment, reconfigurable substrates to create liver models that support infection of a hepatitis virus. It has been reported that co-cultivated liver endothelial cells cause liver hepatocytes to be more susceptible to infection by Hepatitis C. The reconfigurable substrates of the invention could be used to create a co-culture or tri-culture system where endothelial cells maintain and influence hepatocytes separated using the gap configuration. Such a system would mimic in vivo physiology, in which sinusoidal endothelial cells are near hepatocytes but separated by the space of Disse. Also, since hepatocytes are maintained in a pure monolayer on their individual comb fingers, evaluation by microscopy or by RNA, protein, or organelle activity level would be facilitated. In addition, configurable substrates could be used to identify specific molecules that influence hepatitis infectivity. For example, soluble factors from endothelial cells that modulate hepatocyte susceptibility to hepatitis viruses could be identified using aforementioned methods, such as siRNA knockdown.
In other words, another aspect of the invention relates to a method of selectively exposing a mixed culture of cells to a compound comprising the steps of:
culturing a mixed culture of cells comprising a plurality of cells of a first type and a plurality of cells of a second type; wherein the cells of a first type are cultured on a first component, the cells of a second type are cultured on a second component, and the first component is at a distance from or in contact with the second component; and
exposing the cells of a first type on the first component and the cells of a second type on a second component to a compound for a time.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the compound is a toxic compound, exposure to which results in the death of at least some of the cells of a first type, some of the cells of a second type, or cells of both types.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In another embodiment, in addition to the selective stimulation described above, one can separate a subpopulation of cells from a culture in order to assay those cells specifically; this is known as selective interrogation. One example of selective interrogation is shown in FIG. 11 , where SEC cells are separated out from a culture of many cell types, and a Western Blot is performed on the purified SEC population. Another example is in FIG. 15 , where hepatocytes and 3T3 fibroblasts are separated before viability assays are performed on each population.
It follows that one aspect of the invention relates to a method of selectively assaying a subpopulation of cells from a mixed culture of cells comprising the steps of:
culturing a mixed culture of cells comprising a plurality of cells of a first type and a plurality of cells of a second type; wherein the cells of a first type are cultured on a first component, the cells of a second type are cultured on a second component, and the first component is at a distance from or in contact with the second component;
separating the first component from the second component; and
assaying the cells of a first type, the cells of the second type, or both.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the assay is a viability assay.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a first type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are mammalian cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are human cells.
In certain embodiments, the present invention relates to the aforementioned method and any of the attendant limitations, wherein the cells of a second type are selected from the group consisting of cells of the anus, bladder, bile duct, bone, brain, breast, cervix, colon/rectum, duodenum, endometrium, esophagus, eye, gallbladder, head, neck, liver, larynx, lung, mouth, pancreas, penis, prostate, kidney, ovaries, skin, stomach, testicles, and thyroid.
For all of the methods described herein, a variety of different reconfigurable substrates can be used, for a variety of times, in a variety of configurations. For example, In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the distance is in the range of about 1 μm to about 1,000 μm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the distance is in the range of about 10 μm to about 200 μm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the distance is in the range of about 50 μm to about 100 μm.
As used herein, fingers should be understood to be protrusions like the teeth of a comb. See FIG. 1 e for an example.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component comprises a first plurality of fingers.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein each finger in the first plurality of fingers is tapered.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the ratio of the lengths of the ends of each finger in the first plurality of fingers is about 3:1.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component comprises second a plurality of fingers.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein each finger in the second plurality of fingers is tapered.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the ratio of the lengths of the ends of each finger in the second plurality of fingers is about 3:1.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the length of each finger in the first plurality of fingers is about 1 mm to about 50 mm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the length of each finger in the first plurality of fingers is about 1 mm to about 1 mm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the length of each finger in the first plurality of fingers is about 5 mm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the length of each finger in the second plurality of fingers is about 1 mm to 50 mm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the length of each finger in the second plurality of fingers is about 1 mm to about 10 mm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the length of each finger in the second plurality of fingers is about 5 mm.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first plurality of fingers and the second plurality of fingers are structured and arranged to interdigitate with one another in a substantially coplanar fashion.
As used herein latch is a type of mechanical hardware, specifically a flexure, that is used to join two (or more) objects or surfaces together while allowing for the regular or eventual separation of the objects or surfaces. See, for example, the snap-lock arm in FIG. 1 e.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component comprises at least or exactly two latches, and the latches are on opposite sides of the first component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component comprises at least or exactly two latches, and the latches are on opposite sides of the second component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component comprises at least or exactly two slots, and the slots are on opposite sides of the first component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component comprises at least or exactly four slots, and the slots are on opposite sides of the first component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component comprises at least or exactly six slots, and the slots are on opposite sides of the first component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component comprises at least or exactly two slots, and the slots are on opposite sides of the second component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component comprises at least or exactly four slots, and the slots are on opposite sides of the second component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component comprises at least or exactly six slots, and the slots are on opposite sides of the second component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the slots are V-shaped.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component is fabricated from silicon, polystyrene, quartz, glass, fused silica, SU-8, PDMS, polypropylene, epoxies, polymers, ceramics or metals.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component is fabricated from silicon, polystyrene, quartz, glass, fused silica, SU-8, PDMS, polypropylene, epoxies, polymers, ceramics or metals.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component is partially or completely coated with polystyrene.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component is partially or completely coated with polystyrene.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component is partially or completely coated with collagen.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component is partially or completely coated with collagen.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component is fabricated from an optically transparent material.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the first component is fabricated from an optically translucent material.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component is fabricated from an optically transparent material.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the second component is fabricated from an optically translucent material.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the at least one cell of the first type is different that the at least one cell of a second type.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, wherein the at least one cell of a first type is a plurality of cells of a first type; the at least one cell of a second type is a plurality of cells of a second type; and the plurality of cells of the first type are different than the plurality of cells of the second type.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, further comprising the step of altering the distance between the first component and the second component.
In certain embodiments, the present invention relates to any of the aforementioned methods and any of the attendant limitations, further comprising the step of replacing the first component or the second component with a third component; wherein the third component wherein the third component comprises at least one cell of a third type, different from the first type of cell and the second type of cell.
EXEMPLIFICATION
The invention now being generally described, it will be more readily understood by reference to the following examples, which are included merely for purposes of illustration of certain aspects and embodiments of the present invention, and are not intended to limit the invention.
Materials. Collagen-I was purified from rat tails as previously described. Dunn, J. C., Tompkins, R. G. & Yarmush, M. L. (1991) Biotechnol Prog 7, 237-45. Briefly, rat-tail tendons were denatured in acetic acid, salt-precipitated, dialyzed against HCl, and sterilized with chloroform. Since the silicon substrates are opaque, a reflecting non-inverted microscope is required to inspect cells during culture. In order to examine cultures without compromising sterility, a microscopy system was required with an optical working distance greater than the thickness of a covered culture plate. A 5× objective with 36 mm working distance and a 10× objective with a 38 mm working distance (Optical Product Development, Lexington, Mass.) mounted on a Meiji MA655/05 head (Microscope World, Encinitas, Calif.) was used.
Device Fabrication. Microfabrication facilities were utilized at the University of California, Berkeley (U.C. Berkeley Microfabrication Laboratory, Berkeley, Calif.) and the Massachusetts Institute of Technology (Microsystems Technology Laboratories, Cambridge, Mass.), using a similar process at both locations. Device parts were fabricated using commonly utilized MEMS fabrication methods. Good references include papers by Ayon and coworkers (Ayon, A. A., Braff, R., Lin, C. C., Sawin, H. H. & Schmidt, M. A. (1999) Journal of the Electrochemical Society 146, 339-349) and Knobloch and coworkers (Knobloch, A. J., Wasilik, M., Fernandez-Pello, C. & Pisano, A. P. (2003) in 2003 ASME International Mechanical Engineering Congress (American Society of Mechanical Engineers, New York, N.Y. 10016-5990, United States, Washington, D.C., United States), Vol. 5, pp. 115-123). Briefly, a double-sidepolished silicon wafer (4″, 500-μm, University Wafer, South Boston, Mass.) was oxidized (1000° C., O 2 /H 2 O) to grow a 1-μm layer of silicon dioxide. A layer of thick photoresist (Megaposit SPR220, Rohm and Hass, Philadelphia, Pa.) was spin-coated, patterned using a chrome mask and contact alignment (Karl Suss MA6, SUSS MicroTec Inc., Waterbury Center, Vt.), and developed (LDD-26W, Shipley, Marlborough, Mass.). The patterned wafer, or device wafer, was then attached to a handle wafer using a photoresist bond. After etching through the oxide layer (He/CHF 3 /CF 4 plasma), deep reactive ion etching (ICP-ASE, Surface Technology Systems, Newport, UK) was used to etch through the entire device wafer as previously described (Knobloch, A. J., Wasilik, M., Fernandez-Pello, C. & Pisano, A. P. (2003) in 2003 ASME International Mechanical Engineering Congress (American Society of Mechanical Engineers, New York, N.Y. 10016-5990, United States, Washington, D.C., United States), Vol. 5, pp. 115-123). The parts were then released in acetone and cleaned in Piranha solution (4:1 H 2 SO 4 :H 2 O 2 , 120° C., 10 min). Finally, the silicon surface was functionalized for cell culture by spin-coating with polystyrene (100 mg/ml in toluene, 2400 rpm, 1 min) followed by plasma treatment (O 2 , 200 mT, 200 W, 1 min), resulting in a surface comparable to tissue culture plastic. Devices can be reused multiple times (>20). Between experiments, the parts are cleaned in toluene followed by Piranha solution, and polystyrene is reapplied.
Alternative Approach to Device Fabrication. As described above, the silicon device components can cut out of a silicon wafer using a plasma etching process. In the first mask design described above, each device component was cut completely free of the silicon wafer—at the end of the plasma etch, the finished components had no connection with the rest of the wafer. The components were still attached by an adhesive to an underlying substrate. However, if the adhesive failed, which was not uncommon, the components could detach during the etch process, resulting in damage to the components. In an alternative mask design, the components were not etched completely free but instead remained connected to the rest of the wafer by small tethers. After etching was complete, a dicing saw was used to cut the tethers and free the components. This method resulted in a much higher yield (80% vs. 20%) in manufacturing.
The devices do not need to be made from silicon. For example, polyurethane, polystyrene, epoxy, acrylic, glass, or pre-strained polystyrene that shrinks upon heating, may be used. Methods such as casting, molding, laser cutting, water-jet cutting, machining, drill-press, injection molding, knife cutting can aid in the preparation of the devices.
Cell Culture. Primary hepatocytes were isolated from 2- to 3-month-old adult female Lewis rats (Charles River Laboratories, Wilmington, Mass.) weighing 180-200 g, following a modified procedure of Seglen (Seglen, P. O. (1976) Methods Cell Biol 13, 29-83). Detailed procedures for hepatocyte isolation and purification have been previously described (Dunn, J. C., Tompkins, R. G. & Yarmush, M. L. (1991) Biotechnol Prog 7, 237-45). Hepatocyte culture medium consisted of Dulbecco's Modified Eagle Medium with high glucose, 10% (v/v) fetal bovine serum, 0.5 U/mL insulin, 7 ng/mL glucagon, 7.5 g/mL hydrocortisone, and 1% (v/v) penicillin-streptomycin. Swiss 3T3 fibroblasts were purchased from ATCC (Manassas, Va.). J2-3T3 fibroblasts were the gift of Howard Green (Harvard Medical School, Cambridge, Mass.; Rheinwald, J. G. & Green, H. (1975) Cell 6, 331-43). Fibroblast culture medium consisted of Dulbecco's Modified Eagle Medium with high glucose, 10% bovine calf serum, and 1% penicillinstreptomycin.
Device Actuation. Actuation was performed within a biosafety cabinet using stainless steel tweezers (2-mm round tips), sterilized in 70% ethanol before use. Substrates were pushed or picked up using the round hole at the rear of each part. It is possible for the parts to lock together misaligned vertically. Therefore, after configuring substrates in the intended state, plates were covered and examined under the reflecting microscope to verify that interlocked fingers were in-plane. Typically, roughly 5% of interlocked parts were misaligned. To fix alignment, parts were simply separated and locked back together.
Seeding Of Cells Onto Micromechanical Substrates. Polystyrene-coated silicon substrates were placed into individual wells on standard 12-well culture plates. Substrates intended to support hepatocytes were incubated in collagen solution (400 μg/ml in water) at 37° C. for at least 45 min. To provide a flat, uniform surface for seeding, substrates were each locked together with a complementary part, in the contact mode. These complementary parts were utilized only during cell seeding and were set aside afterwards. Substrates were sterilized by soaking in 70% ethanol for 1 hand then washed twice in distilled water. Primary hepatocytes were typically seeded onto the male parts (no arms), while fibroblasts (Swiss 3T3 or J2-3T3) were seeded onto the female parts (with arms) ( FIG. 1A ). Cells were seeded at 500,000 cells/ml, with 1 mL per well, in the appropriate culture medium and incubated for 60 min at 37° C. Plates were shaken every 20 min to resuspend unattached cells. After 60 min, unattached cells were aspirated, the substrate was washed with culture medium, and seeding was repeated with a fresh cell suspension. This process was repeated until the substrate surface was fully coated, usually requiring 2-4 seeding cycles for hepatocytes and 2 seeding cycles for fibroblasts. Within 6 hours of completing cell seeding, the complementary parts were removed from each substrate. Cell-coated substrates were then transferred to fresh wells and incubated overnight in the appropriate medium. The following day, a cell scraper (Fisher Scientific, Pittsburgh, Pa.) was utilized to remove hepatocytes from the rear half of the substrates, in order to leave only the cells attached directly on the comb fingers (plus a border of roughly 1 mm due to imprecise manual scraping) ( FIG. 1A , inset). Hepatocyte- and fibroblast-coated substrates were then assembled into their initial configurations for a particular experiment.
Fluorescent Labels. Hepatocytes were labeled using calcein AM (Molecular Probes, Eugene, Oreg.) at 5 μg/ml in hepatoctye medium. Swiss 3T3 fibroblasts were labeled using CellTracker Orange CMTMR (Molecular Probes) at 0.5 μM in serum-free fibroblast medium. J2-3T3 fibroblasts were labeled using CellTracker Blue CMAC (Molecular Probes) at 2.5 μM in serum-free fibroblast medium. For high-magnification images, hepatocyte membranes were labeled using PHK67 (Sigma-Aldrich, St. Louis, Mo.) at 1:1000 in Diluent C (Sigma). Fibroblast membranes were labeled using Vybrant DiI (Molecular Probes) at 5 μl/ml in serum-free fibroblast medium. Cell nuclei were labeled using Hoechst 33258 (Molecular Probes) at 0.001% in hepatocyte medium.
Functional Assays. Albumin content was measured using enzyme linked immunosorbent assays (MP Biomedicals, Irvine, Calif.) with horseradish peroxidase detection and 3,3′,5,5′-tetramethylbenzidine (Pierce Biotechnology, Rockford, Ill.) as a substrate (Dunn, J. C., Tompkins, R. G. & Yarmush, M. L. (1991) Biotechnol Prog 7, 237-45). All experiments were performed at least twice, with triplicate samples for each condition. One representative outcome is presented for each experiment, with similar trends observed in multiple trials. Fluorescence quantification was performed using MetaVue 6.2r0 software (Universal Imaging Corporation, Downingtown, Pa.).
INCORPORATION BY REFERENCE
All of the U.S. patents and U.S. published patent applications cited herein are hereby incorporated by reference.
EQUIVALENTS
Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims.
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The development and function of living tissues depends largely on interactions between cells that can vary in both time and space; however, temporal control of cell-cell interaction is experimentally challenging. By employing a micromachined silicon substrate with moving parts, herein is disclosed the dynamic regulation of cell-cell interactions via direct manipulation of adherent cells with micron-scale precision. The inventive devices and methods allow mechanical control of both tissue composition and spatial organization. The inventive device and methods enable the investigation of dynamic cell-cell interaction in a multitude of applications, such as intercellular communication, spanning embryogenesis, homeostasis, and pathogenic processes.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is related to sanitary paper such as facial tissues.
[0003] 2. Description of the Related Art
[0004] Recently, so-called luxury type facial tissues have come onto the market which touch softly on the skin by containing a solution such as softener in the tissues. These tissues have become popular as it hardly stings the skin by blowing one's nose, or makes the nose to turn reddish.
[0005] However, usual sanitary paper which contains a solution could not prevent the sting and the redness of the skin sufficiently.
[0006] Thus, our diligent effort revealed that when usual sanitary paper with a solution touches the corneal surface, the sheet removes the sebum of the surface. Therefore, when the sanitary paper touches the same part of the skin frequently, the sebum will be removed first by the sanitary paper and then, at the place where the sebum was removed, the moisture inside the corneum will be removed. Accordingly, the skin will become rough and will turn reddish.
SUMMARY OF THE INVENTION
[0007] The major object of the present invention is to provide sanitary paper which is excellent in touch onto skin such as moistness and softness and which makes hard to get skin stung and reddish even if the sanitary paper touches the skin frequently.
[0008] The above-mentioned object can be attained by the sanitary paper of the present invention which comprises a paper base which contains a solution, in which an oil absorbance is 7.0 mm or less. The oil absorbance mentioned in the present invention is measured, under the standard condition which is regulated by Japanese Industrial Standard P8111, according to the Klemm water absorbance test which is regulated by Japanese Industrial Standard P8141, where water is replaced with salad oil on the market (made by THE NISSHIN OIL MILLS, LTD.). However, measuring time length is 60 seconds and the flow of the paper is longitudinal way (which is the way of manufacturing line flow). That is, a specimen of the sanitary paper is put in a longitudinal way, the lower edge of the paper is dunked into the salad oil, the height of the rising the salad oil is measured 60 seconds later and is regarded as the mean value of ten points of the specimen.
[0009] Usual sanitary paper, on which a solution was applied, has a character of oil absorption which is too high and, as shown in FIG. 1 ( a ), when usual sanitary paper and the skin touch each other frequently, the sebum of corneal surface, and then, the moisture inside the corneum will be removed. As a result, the skin will become rough and will turn reddish.
[0010] On the other hand, according to the present invention, when the oil absorbance is 7.0 mm or less, it will be difficult to remove the sebum of corneal surface by a sanitary paper as shown in FIG. 1 ( b ), and therefore the moisture inside the corneum will be preserved. As a result, the skin will not become rough or reddish easily.
[0011] According to the present invention, sanitary paper is proposed in which a moisture content of the sanitary paper is 9.50 to 15.00%, determined in accordance with Japanese Industrial Standard P8127, after controlling the humidity of the sanitary paper under the condition that is regulated by Japanese Industrial Standard P8111.
[0012] A usual product on the market has a low moisture content. Unlike this, the present invention having an elevated moisture content gives an excellent touch onto skin which is realized mainly as a satisfactory moistness. In addition, even if there is not much sebum of corneal surface when the sanitary paper touches the skin, it will be difficult to remove the moisture inside the corneum. Therefore, even if the sanitary paper touches the skin frequently, the skin will not become rough or reddish easily.
[0013] According to the sanitary paper of the present invention, it is preferable that the solution content per unit volume of a paper base is 46.0 to 160.0 mg/cm 3 . By employing the solution specified above, the oil absorbance of the sanitary paper can be in the range according to claim 1 . When the solution content becomes more than 160.0 mg/cm 3 , the sanitary paper will show a sticky feeling and will give the users an unpleasant feeling.
[0014] According to the sanitary paper of the present invention, the solution is preferably a slightly acid solution that is pH 5.0 to 6.0. By keeping the pH of the solution at a slightly acidic level similar to that of a healthy skin, the skin will not turn into alkaline or strongly acidic even when the sanitary paper touches the skin. Accordingly, it will prevent the skin effectively from being rough affected by the pH of the solution.
[0015] Further, according to the sanitary paper of the present invention, it is preferable that the solution contains at least one of moisturizers selected from polyhydric alcohols such as glycerin and propylene glycol, or saccharides such as sorbitol and glucose, or glycol-based solvents or derivatives thereof. By using such solutions, the sanitary paper may have a rich moisture and an excellent moistness.
[0016] Further, according to the sanitary paper of the present invention, it is preferable that the solution contains at least one of softeners selected from anionic surfactant or nonionic surfactant or cationic surfactant or zwitterionic surfactant. By using such solution, the sanitary paper may have an excellent softness.
[0017] Further, according to the sanitary paper of the present invention, it is preferable that the solution contains at least one of antioxidants selected from vitamin C and vitamin E. Vitamin C or vitamin E is suitable for the antioxidant in the present invention. Vitamin E is an ingredient which has a strong reducing force and possesses an antioxidant action such as elimination of activated oxygen-free radical and a prevention of the generation of lipid peroxide. Accordingly, vitamin E will work as a stabilizer of the solution and also when the sanitary paper is given to the skin of the user, it will exhibit an oxidization prevention effect and a circulation of the blood promotion effect onto the sebum of the skin. Vitamin E also possesses a moisture preservation function. On the other hand, vitamin C has an antioxidant action on sebum, as same as vitamin E. As vitamin C acts to reduce vitamin E, when vitamin C and vitamin E both are used together, vitamin C works as a promoter of vitamin E, in which vitamin C reduces the vitamin E which was oxidized by activated oxygen and such, and maintains the strong antioxidant action on sebum of vitamin E.
[0018] Further, according to the sanitary paper of the present invention, it is preferable that the solution contains a collagen. 90% of the dermis is formed by collagen and if the collagen decreases, the skin will lose their moisture and fitness. Therefore, by incorporating the collagen into the sanitary paper, moisturizing effect on the ski will be exhibited upon contact with a skin, as well as a moisturizing effect also on the sanitary paper.
[0019] Further, according to the sanitary paper of the present invention, it is preferable that the bending hardness B of the sanitary paper is 0.0040 to 0.0060 g·cm 2 /cm, determined by using a pure bending tester. The bending hardness B of the present invention is described in below. A 20 cm wide paper specimen, having a 1 cm chuck interval, is bended by pure bending way, a bending way which always maintains one side of the paper an arc. First, bend it toward the front side till the maximum curvature reaches 2.5 cm −1 and put it back to the origin, and next, bend it toward the backside till the maximum curvature reaches −2.5 cm −1 and put it back to the origin. At this moment, in the relation between curvature and bending moment, the bending hardness B of the present invention is indicated as an average inclination between curvature 0.5 and 1.5 cm −1 .
[0020] The bending hardness B of a usual product on the market is high. On the other hand, when the bending hardness B is reduced according to the present invention, the sanitary paper will be excellent in touch onto skin, mainly the softness taking a leading part. Moreover, when the paper base is impregnated with moisturizer or softener, there will be an advantage that moistness or softness will be promoted.
[0021] Further, according to the sanitary paper of the present invention, it is preferable that the softness per unit weight of the sanitary paper is 5.4 to 6.4 m 2 /100. As used herein, the term “softness” denotes a value of resistance (a mean value of lengthwise and widthwise values) when a 10 cm wide paper is pushed into a 5.0 mm wide crevice by a terminal. Also, unit weight is a value determined in accordance with Japanese Industrial Standard P8124, The value of softness of usual product on the market was too high. When the value of softness is in the low range according to the present invention, the sanitary paper will be excellent in softness.
[0022] Further, according to the sanitary paper of the present invention, it is preferable that the unit weight per 1-ply tissues is 10 to 35 g/m 2 and the sanitary paper consists of 1 to 3-ply tissues, a lengthwise tensile strength in a dry condition is 60 to 160 N/m, a crosswise tensile strength in a dry condition is 20 to 60 N/m, and the ratio of the crosswise tensile strength to the lengthwise tensile strength both in the dry condition is 1.5 to 5.0. The tensile strength of the present invention is, a tensile strength determined by tensile strength testing method which is regulated by Japanese Industrial Standard P8116.
[0023] In general, the strength of sanitary paper is reduced when the paper is merely softened. Accordingly, it is preferable that the tensile strength be kept within the range of the present invention.
[0024] Further, according to the sanitary paper of the present invention, it is preferable that the NBKP content of pulp material is 30.0 to 80.0%. The present invention is especially suitable for above-mentioned objects when the present invention is sanitary paper specified above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a schematic diagram showing a function of sanitary paper containing a solution.
[0026] FIG. 2 is a schematic diagram showing a testing method of bending hardness.
[0027] FIG. 3 is a schematic diagram showing a relation between curvature and bending moment.
[0028] FIG. 4 is a schematic diagram showing a relation of compression characteristic FIG. 5 is a schematic diagram showing a testing method of surface characteristic.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] The sanitary paper of the present invention comprises at least one of the basic structures mentioned below, although it is a matter of course that sanitary paper which fulfills the both conditions is more preferred.
[heading-0030] The First Basic Sturucture
[0031] A paper base is contained a solution, and the oil absorbance of the sanitary paper is made to be 7.0 mm or less. The oil absorbance of the sanitary paper is measured, under the standard condition which is regulated by Japanese Industrial Standard P8111, according to the Klemm water absorbance test which is regulated by Japanese Industrial Standard P8141, where water is replaced with salad oil on the market (made by THE NISSHIN OIL MILLS, LTD.). The measuring time length is 60 seconds and the flow of the paper is longitudinal way (which is the way of manufacturing line flow). That is, a specimen of the sanitary paper is put in a longitudinal way, the lower edge of the paper is dunked into the salad oil, the height of the rising the salad oil is measured 60 seconds later and is regarded as the mean value of ten points of the specimen.
[heading-0032] The Second Basic Structure
[0033] The humidity of sanitary paper is controlled under the condition that is regulated by Japanese Industrial Standard P8111 and a moisture content of sanitary paper is 9.50 to 15.00%, determined in accordance with Japanese Industrial Standard P8127.
[heading-0034] A Typical Structure
[0035] In the embodiments of this present invention, the following typical structure can be adopted on above-mentioned basic structure.
[0036] As a paper base, publicly noticed product can be used without question. A product having the NBKP content of pulp material is 30.0 to 80.0%. (in accordance with Japanese Industrial Standard P8120), especially 50.0 to 70.0% is suitable as a paper base of the present invention.
[0037] The unit weight (determined in accordance with Japanese Industrial Standard P8124) of sanitary paper is preferably 10.0 to 35.0 g/m2. The paper thickness of sanitary paper is preferably 130 to 200 μm by two-ply tissues. The crape rate of sanitary paper is preferably 15.0 to 26.0.
[0038] When a solution is contained in a paper base, usually an oil absorbance can be 1.0 to 7.0 mm, and especially 4.0 to 6.5 is preferable. Such sanitary paper can be manufactured by applying the solution onto the paper base (other solution applying methods can also be adopted) while adjusting the amount of the solution content per unit volume of a paper base within 46.0 to 160.0 mg/cm 3 , especially within 48.0 to 60.0 mg/cm 3 .
[0039] The solution content of the sanitary paper was determined as below. By using a Soxhlet extractor, approximately 10 g of specimen were immersed in 120 to 140 ml of ethanol-benzene solvent (the solvent ratio of ethanol to benzene is 1:1) and were heated and extracted for four hours while keeping the extract liquid lightly boil over a warm bath, and then left to stand in a drier which was held at constant temperature 150±2° C. for 90 minutes and the weight of the extract was measured and the measurement was divided by absolute dry weight of specimen to determine the rate as a percentage %. The solution content per unit volume of paper (=an amount of the applied solution) was calculated by the next formula.
An amount of the applied solution basic weight (per ply)×2 (plies)×solution content (%)×1000÷(volume per unit area)
[0040] However, a volume per unit area is, paper thickness (μm)÷10000×100×100.
[0041] Accordingly, by making the oil absorbance low enough, it will be difficult to remove the sebum of corneal surface by sanitary paper, and therefore the moisture inside the corneum will be preserved by sebum. As a result, the skin will not become rough or reddish easily. Further, when an amount of the solution content becomes more than 160.0 mg/cm 3 , the sanitary paper will show sticky feeling and will give the users an unpleasant feeling.
[0042] For a solution, publicly noticed product can be used without question. Especially, when a solution is a slightly acid solution of pH 5.0 to 6.0, more suitably of pH 5.3 to 5.7, the skin will not turn into alkaline even when the sanitary paper touches the skin. Accordingly, the skin will be prevented effectively from the roughness which will be caused by an affection of the pH of the solution. The pH adjustment means are to add a pH adjustment solvent, that are acid or basic, into the solution. When the solution is strongly acidic, a sodium hydroxide solution or a potassium hydroxide solution can be added and when the solution is a neutral or an alkaline, a citric acid or a malic acid or a lactic acid can be added.
[0043] Ingredients of the solution of the present invention can be chosen suitably from moisturizer, softener and antioxidant. Choosing all of them are specially preferred. For the moisturizer, a polyhydric alcohol, sorbitol and a solvent of glycol series are good for use. By using these moisturizers, the moisture of the sanitary paper will become rich enough. Besides, collagen can be used with these moisturizers, and by this, moisture will be provided onto the skin effectively also.
[0044] A softener can be chosen suitably from anionic surfactants, nonionic surfactants, cationic surfactants and zwitterionic surfactants. Especially, an anionic surfactant is suitable. When an anionic surfactant are chosen, the firmness (a hardness of bending) of the paper base will be decreased to the range mentioned above, resulting in a further improvement in the moistness attributable to the moisturizers and the softness attributable to the softeners. As an anionic surfactant, a carboxylate-based, sulfonate-based, sulfate ester salt-based, phosphate ester salt-based surfactant may be employed. An alkyl phosphate ester salt is especially preferred.
[0045] As a nonionic surfactant, a polyhydric alcohol monofatty acid ester such as a sorbitan fatty acid ester, diethylene glycol monostearate, diethylene glycol monooleate, glyceryl monostearate, glyceryl monooleate, propylene glycol monostearate, and N-(3-oleyloxy-2-hydroxypropyl)diethanolamine, polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbitol beeswax, polyoxyethylene sorbitan sesquistearate, polyoxy ethylene monooleate, polyoxyethylene monolaurate, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether may be employed.
[0046] As a cationic surfactant, a quaternary ammonium salt, amine salt or amine can be used. As a zwitterionic surfactant, a secondary or tertiary amine aliphatic derivative or a heterocyclic secondary or tertiary amine aliphatic derivative carrying a carboxy, sulfonate and sulfate can be employed.
[0047] As an antioxidant, vitamin C and vitamin E can be used. When the vitamins are used, the effect of preserving moisture of the sanitary paper and the effect of preventing skin from turning into acid will be exhibited. Especially, when vitamin C and vitamin E both are used together, vitamin C works as a promoter of vitamin E, therefore the antioxidant action of vitamin E can be maintained longer. Vitamin E is an ingredient which has a strong reducing force and possesses an antioxidant action such as elimination of activated oxygen-free radical and a prevention of the generation of lipid peroxide. Accordingly, vitamin E will work as a stabilizer of the solution and also when the sanitary paper is given to the skin of the user, it will exhibit an oxidization prevention effect and a circulation of the blood promotion effect onto the sebum of the skin. Vitamin E also possesses a moisture preservation function. On the other hand, vitamin C has an antioxidant action on sebum, as same as vitamin E. As vitamin C acts to reduce vitamin E, when vitamin C and vitamin E both are used together, vitamin C works as a promoter of vitamin E, whereby reducing the vitamin E once oxidized by the activated oxygen, resulting in the preservation of the strong antioxidant action on sebum of vitamin E.
[0048] In addition, a collagen can be added if necessary to exert a moisturizing effect on the skin as well as a moisturizing effect also on the sanitary paper. Although an amount of collagen to be added can be determined suitably, it is preferable that the amount of collagen be as same level as antioxidant on the point of cost-effectiveness.
[0049] When using the above-mentioned solution, it is preferable to adopt the following combination.
[0050] Active ingredient from 60 to 100% by weight (especially from 80 to 100% by weight)
[0051] Moisturizer from 95 to 100% by weight (especially from 95.5 to 97.0% by weight)
[0052] Softener from 0 to 5% by weight (especially from 3.0 to 4.5% by weight)
[0053] Antioxidant from 0.000001 to 0.001% by weight Water from 0 to 40% by weight
[0054] The moisture content of the sanitary paper of the present invention of 9.50 to 12.00% is especially preferred
[0055] It is preferable for the sanitary paper of the present invention that the bending hardness B of the sanitary paper is 0.0040 to 0.0060 g cm 2 /cm. The bending hardness B of the present invention is determined as below. That is, by using an “Automatic Pure Bending Tester KESFB2-AUTO-A”, manufactured by KATO TECH CO., LTD., and as shown in FIG. 2 , a 20 cm wide paper specimen, having a 1 cm chuck interval, is bended by pure bending way, a bending way which always maintain one side of the paper an arc. First, bend it toward the front side till the maximum curvature reaches 2.5 cm −1 and put it back to the origin, and next, bend it toward the backside till the maximum curvature reaches −2.5 cm −1 and put it back to the origin. At this moment, relation between curvature and bending moment is evaluated. This relation is obtained as a value on the Hisrelisls curve line as shown in FIG. 3 . And the mean value of lengthwise and crosswise of bending hardness B (the mean B), in which the bending hardness B is indicated as an average inclination between curvature 0.5 and 1.5 cm” 1 , is the bending hardness B of the present invention. As the mean value of bending hardness B (the mean B) become higher, the sanitary paper will become firmer and more difficult to bend.
[0056] Further, it is preferable for the sanitary paper of the present invention that the softness per unit weight of the sanitary paper is 5.4 to 6.4 m 2 /100. The “softness” of the present invention is, a value of resistance (a mean value of lengthwise and crosswise) when a 10 cm wide paper is pushed into a 5.0 mm wide crevice by a terminal and it can be measured by the so-called “Handle O Meter”.
[0057] Further, it is preferable for the sanitary paper of the present invention that the compression characteristic TM, T 0 and (T 0 -TM) is within the next range.
[0058] A thickness TM under a 50 g/cm 2 load: 0.160 mm or more for 1-ply tissues
[0059] A thickness T 0 under a 0.5 g/cm 2 load: 0.350 mm or less for 1-ply tissues
[0060] T 0 -TM: 0.200 mm or less for 1-ply tissues TM/(T 0 -TM): from 0.800 to 1.500
[0061] This compression characteristic test is done by using a “Handy Compression Tester KES G5”, manufactured by KATO TECH CO., LTD. A paper specimen was compressed till the maximum compression load 50 g/cm 2 between iron plates, which plate has a circle plane with a 2 cm 2 compression area. And the compression characteristic of the paper specimen returning to former state was evaluated. The compression characteristic indicated at this moment, may be described as a relation shown in FIG. 4 .
[0062] Further, it is preferable for sanitary paper of the present invention whose surface characteristic MMD and MIU are within the following range.
MMD (the mean deviation of friction coefficient): from 0.0180 to 0.0250 MIU (the mean friction coefficient): from 0.4000 to 0.5000
[0065] This surface characteristic test is done by using a “Friction Sensitivity Tester KES-SE”, manufactured by KATO TECH CO., LTD. This tester, as shown in FIG. 5 , measures the friction coefficient as below. While contacting a paper specimen with a friction probe, made by a piano wire which has a cross section with a diameter of 0.5 mm and having a 5 mm-long contacting surface, by touching a log contact pressure, a 20 g/cm tension is applied to the paper specimen in the moving direction and, at the same time, the paper specimen moves 2 cm at a speed of 0.1 cm/sec and the friction coefficient is measured. Furthermore, the mean deviation of friction coefficient MMD is a change of the surface thickness when the friction probe moved, that is, a value of friction coefficient divided by friction distance (the moving distance ˜2 cm).
[0066] On the other hand, the sanitary paper of the present invention is preferable for a product which is used for rubbing the skin such as facial tissue or toilet paper, but also it can be used for other purposes too. When such a purpose has been considered, it is preferable for the sanitary paper of the present invention that the unit weight per 1-ply tissues is 10 to 35 g/m 2 and the sanitary paper consists of 1 to 3-ply tissues. Further, it is preferable for the sanitary paper of the present invention that the lengthwise tensile strength in dry condition is 60 to 160 N/m, especially 80 to 140 N/m, crosswise tensile strength in dry condition is 20 to 60 N/m, especially 25 to 40 N/m, and the ratio of the lengthwise tensile strength in dry condition to the crosswise tensile strength in dry condition is 1.5:1.0 to 5.0:1.0, especially 2.0:1.0 to 3.5:1.0. Still more, it is preferable for the sanitary paper of the present invention that the tensile strength in wet condition is, the longitudinal: 30.0 to 60.0 N/m, and the widthwise: 10.0 to 30.0 N/m −1 When the sanitary paper simply softens, the strength of the paper itself will drop too but by maintaining the tensile strength within such a range, the sanitary paper will become suitable for rubbing skin such as a facial tissue.
EXAMPLE
[0067] As shown in Tables 1 and 2, various physical properties of various facial tissues were measured, calculated and evaluated organoleptically (an example of the present invention, traditional product, and commercial products A, B. C and D). The method of the measurement, calculation and organoleptic evaluation are written below. The measurements of the physical properties were carried out under the conditions that are regulated by Japanese Industrial Standard P8111. Further, the consequence of measurements and such are shown in Table 3.
(1) Basic weight (1-plytissues): measured in accordance with Japanese Industrial Standard P8124. (2) Paper thickness (2-plytissues): A paper thickness is measured by using a dial thickness gauge “PEACOCK G types manufactured by OZAKI MFG. CO., LTD. under the conditions that are regulated by Japanese Industrial Standard P8111. Typically, first check that there is no rubbish or dust between the plunger and the measuring pedestal. Then, put down the plunger on the measuring pedestal, set the dial of the dial thickness gauge at 0, raise the plunger and put the specimen (a facial tissue) onto the pedestal of the tester. And then, put down the plunger slowly and read the gauge. At this moment, merely the plunger is put on the specimen. The measurement is done on one sheet and the mean value of 10 measurements is the paper thickness. (3) Density: calculated by the next formula. Basic weight×2/(paper thickness/10000×100×100. (4) Solution content: as mentioned above. (5) Solution content per volume unit of the paper: as mentioned above. (6) Oil absorbance: as mentioned above. (7) Compound ratio of NBKP: measured in accordance with Japanese Industrial Standard P8120. (8) Crape rate: calculated by the next formula.
((A circumferential speed of the drier while manufacturing paper)−(Circumferential speed of a reel))/(Circumferential speed of the drier while manufacturing paper)×100
(9) Tensile strength: measured in accordance with Japanese Industrial Standard P8113. (10) Ratio of a lengthwise tensile strength to a crosswise tensile strength: calculated by next formula. Lengthwise tensile strength/Crosswise tensile strength (11) Stretch rate: An elongation at break in a lengthwise tensile strength test. (12) Moisture content: measured in accordance with Japanese Industrial Standard P8127. (13) Softness: A softness is measured by “Handle O Meter”. (14) Bending hardness B: measured by using a pure bending tester (“Automatic Pure Bending Tester KESFB2-AUTO-A”, manufactured by KATO TECH CO., LTD.). Further, as a bending hardness B become higher, the characteristic of facial tissue will become firmer and more difficult to bend. (15) T 0 and Tm: measured by using a compression tester (“Handy Compression Tester KES-G5”, manufactured by KATO TECH CO., LTD.). Further, as T 0 -TM become higher, it shows that the feel of the paper become soft. (16) Mean friction coefficient MIU and a friction distance MMD: measured by using a surface characteristic tester (“Friction Sensitivity Tester KES-SE”, manufaotured by KATO TECH CO. LTD.).
[0084] (17) Organoleptic evaluation: conducted by blowing one's nose for the designated number of times and scoring how hard to feel pain according to a five-grade system. The values are the mean value of 20 people of men and women.
TABLE 1 Example of the present Usual Product A on Product B on Product C on Product D on invention product the market the market the market the market Unit weight (g/m 2 ) 17.5 17.1 15.1 17.8 15.1 18.3 Paper Thickness 2-ply tissues (μm) 160 134 142 163 139 162 Volume per area unit of the paper 160 134 142 163 139 162 (cm 3 /m 2 ) Solution content (wt %) 23.4 17.6 19.3 19.8 3.7 18.7 Solution content per volume unit of the 51.2 45.0 41.0 43.2 8.0 42.2 paper (mg/cm 3 ) Oil absorbance (mm) 5.5 9.0 8.3 8.0 7.6 7.2 pH of solution 5.6 6.5 — — — — NBKP content (wt %) 60.0 60.0 — — — — Crape rate (%) 22.0 22.0 — — — — Lengthwise tensile strength in dry 83.2 184.0 133.6 86.0 141.2 86.4 condition (N/m) Crosswise tensile strength in dry 22.0 36.0 45.2 31.6 29.2 28.8 condition (N/m) Ratio of lengthwise tensile strength to 3.78 5.11 2.96 2.72 4.84 3.00 crosswise tensile strength in dry condition Longitudinal stretch rate (%) 11.7 10.9 13.1 11.8 10.5 11.7 Lengthwise tensile strength in wet 40.4 79.6 46.8 31.6 36.0 37.6 condition (N/m) Crosswise tensile strength in wet 12.0 18.4 19.6 14.0 9.2 15.6 condition (N/m) Moisture content (%) 10.02 9.14 8.16 9.11 8.16 9.21 Softness (g) 1.10 1.16 1.32 1.19 1.26 1.18 Softness/unit weight × 100 (m 2 /100) 6.286 6.784 8.742 6.685 8.344 6.488
[0085]
TABLE 2
Example of
the present
Usual
Product A on
Product B on
Product C on
Product D on
invention
product
the market
the market
the market
the market
Bending hardness B
0.0050
0.0068
0.0095
0.0075
0.0094
0.0062
(gcm2/cm)
T0 (mm)
0.307
0.359
0.385
0.422
0.364
0.423
Tm (mm)
0.162
0.133
0.152
0.149
0.156
0.148
T0 − Tm (mm)
0.145
0.226
0.233
0.273
0.208
0.275
Tm/(T0 − Tm)
1.117
0.588
0.652
0.546
0.750
0.538
MIU
0.4373
0.4990
0.3443
0.3879
0.2812
0.4009
MMD
0.0239
0.0232
0.0248
0.0199
0.0222
0.0209
[0086]
TABLE 3
Example of
the present
Usual
Product A on
Product B on
Product C on
Product D on
Organoleptic evaluation
invention
product
the market
the market
the market
the market
The hardness of nose
4.63
3.00
3.13
3.23
3.13
3.45
to get painful
The feel of moistness
4.25
3.00
2.50
3.00
2.50
3.50
The feel of softness
4.38
3.00
2.50
3.00
2.75
3.38
The feel of thickness
4.25
3.00
3.13
3.63
3.13
3.25
Overall evaluation
4.38
3.13
2.25
3.00
2.38
3.38
[0087] As the example according to the present invention have a lower oil absorbance compared to others, so that it will not absorb oil easily, and also have a high solution content and a high moisture content, as shown in Tables 1 to 3, the example acquired remarkably superior result in the Organoleptic evaluation. According to the present invention, the example turn out to be sanitary paper which is excellent in touch onto skin such as moistness and softness and which makes hard to get skin stung and red even if the sanitary paper touch the skin frequently.
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It is intended to provide sanitary paper which is excellent in texture such as moistness and softness and scarcely causes skin irritation or blushing even if it is brought into contact with the skin frequently. Namely, sanitary paper having an oil absorbance specified in JIS P8141 of 7 mm or less and a moisture content of from 9.50 to 15.00% (measured in accordance with JIS P8127 after conditioning in accordance with JIS P8111); carrying a solution, which contains a moistening agent, a softener, an antioxidant and so on, coated in a dose of 46.0 to 160.0 mg/cm3 of the paper base; and having a bending hardness B measured with the use of a pure bending machine of from 0.0040 to 0.0060 g·cm 2 /cm.
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This is a continuation of application Ser. No. 632,516, filed July 19, 1984, now abandoned.
FIELD OF THE INVENTION
This invention relates to the aspiration of liquid into a container from which it is dispensed. More specifically, it relates to the detection of when it is appropriate to commence such aspiration.
BACKGROUND OF THE INVENTION
Liquid dispensers have been used in analyzers for the detection of the concentration of liquid analytes using as analysis means, test elements that contain within themselves the necessary reagents to permit such detection. Examples of such analyzers are described in U.S. Pat. Nos. 4,287,155, issued Sept. 1, 1981, and 4,340,390, issued July 20, 1982. Examples of such test elements appear in U.S. Pat. Nos. 3,992,158, issued Nov. 16, 1976., 4,053,381, issued Oct. 11, 1977; and 4,258,001, issued Mar. 24, 1981. The conventional method for dispensing liquid onto such test elements using such analyzers has been to aspirate test liquid from a relatively large container, into a dispensing container. The dispensing container is then moved to a position immediately above such a test element, and a fraction (e.g., 10 μl) of the aspirated liquid is dispensed. The dispensing container is fluidly connected, in such analyzers, to a pressurizing means that generates both the operative partial vacuum needed to aspirate the needed amount of liquid into the container, and the partial pressure operative to dispense that aspirated liquid, in fractional amounts, onto a plurality of test elements. A pressure transducer is also conventionally included to ascertain the pressure within the container, so as to detect the occurrence of the desired dispensing event versus a failure to dispense. A microprocessor generally is used to control the apparatus in response to the conditions sensed.
Such conventional analyzers include a motor for raising and lowering the dispensing container, removably mounted on a probe, relative to the large container that supplies the test liquid. Such motors usually are preset to move the dispensing container a fixed distance into such large containers. This has functioned well when the level of the liquid within such large containers has been generally constant, and therefore predictable. However, usually the level is not constant. That is, although the large containers usually have a prescribed protocol that governs their filling, in the case where the dispensing apparatus is used for clinical analysis of body fluids, operators find it more convenient to overfill. Even the overfill is not necessarily constant. Because of the lack of predictability, the motor is preset to accommodate the lowest possible liquid level as the "nominal" liquid level. Unfortunately, this means that the exterior of the dispensing container becomes excessively wetted with the test liquid in those containers having more, and especially those with much more, than the minimum volume providing such lowest level. It has been found that such excessive wetting tends to encourage perfusion during subsequent dispensing. As used herein, "perfusion" means movement of the liquid being dispensed, up the exterior surface of the dispensing container, rather than down onto the test element. As is readily apparent, such perfusion prevents some or all of the desired test liquid from reaching the test element.
What then has been needed is a way of detecting when the dispensing container has penetrated the air-liquid interface within the large container. Although electrical contact of an electrically conductive dispensing container and the test liquid has been used in prior devices, such a technique requires dispensing containers made of especially conductive materials, which therefore become a permanent part of the device. In contrast, the dispensing containers disclosed in the aforesaid analyzer patents have been disposable after each test sample has been dispensed onto one or more test elements. Disposability is practically essential to prevent one test sample from contaminating another.
U.S. Pat. No. 3,894,438 discloses yet another method of detecting the penetration of the air liquid interface. In that patent, the sampling probe is provided with a sensing probe that is separate from but connected to the sampling probe so that the sensing probe enters the liquid phase after the sampling probe. A separate gas source is provided to the sensing probe, to cause an air stream to issue from the sensing probe. When the sensing probe reaches the air-liquid interface, the resistance to the outflowing air changes, and this change in pressure generates a signal that is indicative of the penetration having occurred.
The approach described in the '438 patent does permit the use of disposable dispensing containers. However, one drawback of such an approach is that it requires a second probe besides the sampling probe. Furthermore, a separate gas supply is also needed.
Thus, prior to this invention there has been a need for a simple mechanism for detecting the location of the air-liquid interface in sample supply containers having varying levels of liquids, that permits the use of disposable dispensing containers.
SUMMARY OF THE INVENTION
This invention is based upon the discovery that the penetration of the air-liquid interface can be sensed using, in part, the dispensing apparatus used to dispense the liquid.
More specifically, there is provided an aspirating control system in apparatus for aspirating and dispensing liquid and including a probe for removably mounting a container having an aspirating and dispensing aperture; pressurizing means fluidly connected to the probe for generating an operative pressure differential, relative to atmospheric pressure, within a mounted container; and moving means for advancing the probe and such mounted container toward, and away from, a nominal liquid level location. The control system comprises
(a) means for controlling the advance of the probe in increments,
(b) means for actuating the pressurizing means to generate a pressure differential in such container, relative to atmospheric pressure, that is sufficient to indicate whether such container aperture is closed by the liquid,
(c) means for detecting and signalling the pressure produced within such container by the pressure differential; and
(d) means for comparing the signalled pressure against a reference value determinative of the presence of liquid in the container aperture.
In accord with another aspect of the invention, there is provided a method for detecting penetration of an air-liquid interface by an aspirating and dispensing apparatus, comprising the steps noted for the means (a) through (d) recited in the previous paragraph.
Thus it is an advantageous feature of the invention that no additional air supply or sensing probe is required besides the pressurizing means and probe already used to aspirate and then dispense the aspirated liquid, to detect in a controlled manner for disposable dispensing containers, whether penetration of the liquid by the dispensing container has occurred.
It is a related advantageous feature of the invention that a minimum amount of external wetting of the dispensing container is required for aspiration, thereby reducing perfusion.
Other advantageous features will be readily apparent from the following Description of the Preferred Embodiments when read in light of the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of a dispensing apparatus with which the method of the invention can be practiced;
FIG. 2 is a fragmentary, partially schematic view illustrating the steps of the method, wherein parts and positions are not shown to scale;
FIG. 3 is a schematic illustration of a microprocessor useful as a control means;
FIG. 4 is an example of a signal trace generated by the transducer when carrying out the steps of the invention; and
FIG. 5 is a flow chart for programming the control means of the described apparatus to carry out the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention is particularly useful in colorimetric and potentiometric assays using analyzers and dried test elements of the type described in the above-noted patents. In addition, the invention is useful in any dispensing apparatus or method which aspirates liquid after moving the dispensing container from the atmosphere into a liquid phase, regardless of the steps that follow the dispensing of the aspirated liquid.
Terms such as "up", "down", "lower", "vertical", "horizontal", and "bottom", as used herein refer to the orientation of parts when the apparatus is positioned in its customary position of use.
A portion of a preferred dispensing apparatus 10 is illustrated in FIGS. 1 and 2. A plurality of relatively large sample containers 20 is provided in a tray 22, which also supports removable, disposable dispensing containers 30. The containers 30 have, FIG. 2, a larger aperture 32 at one end to mate with the probe, and a smaller aperture 34 at the opposite end for aspirating and dispensing. Each of containers 20 is preferably provided with a pierceable closure or cap 24, FIG. 1. A probe 40 is mounted for vertical and horizontal movement on a frame 42, such movement being provided respectively by a motor 44 and gear 45, and by a car 48 carrying the probe 40 horizontally on rails 50. Motor 44 can be a stepper motor or a D.C. motor with feedback control. The combined movement of the car and probe is effective to carry the probe within the plane noted as "A", FIG. 1.
A pressure line 52 provides a partial vacuum or a partial pressure, relative to atmospheric, to a dispensing container 30 picked up by the probe. The pressure or vacuum is provided by means such as a piston 60 and piston chamber 62, FIG. 2, driven by appropriate motor means 64. For example, movement of piston 60 from position "A" down to position "X" creates the operative partial vacuum that aspirates the liquid from container 20 into container 30 at the appropriate time. A pressure transducer 70 is used to sense the pressure in container 30, for example to determine when proper dispensing of the liquid out of container 30 occurs.
Alternatively, piston chamber 62 and its piston can be part of probe 40 so as to move up and down with the probe.
Appropriate control means 80 are provided to coordinate the actuation of motor 44 and motor 64, in response to conditions sensed by e.g., transducer 70. Control means 80 can comprise a microprocessor or hard-wired logic circuits. Most preferably, it includes a microprocessor 82, FIG. 3, particularly in light of the programming discussed hereinafter. As is conventional, such a microprocessor comprises a central processing unit 84, for example, an Intel 8086 chip, and memory unit 86 comprising one or more RAM's 88 and optionally one or more E PROM's 90. The microprocessor preferably is also wired to standard input/output devices, as shown, if the dispensing apparatus is part of a complete analyzer.
In accord with one aspect of the invention, the aforesaid apparatus is used as follows to detect the penetration of the liquid meniscus M, FIG. 2, by the aperture 34 of container 30: Assume the total distance from aperture 34 to a point that will always penetrate the liquid (the minimum fill) is initially dimension Y. (This dimension is obtained with container 30 already penetrated through any cap on container 20, FIG. 1.) While container 30 is still at atmospheric pressure, the reference value needs to be established. This can be done two different ways: the signal generated by the pressure transducer before motor 64 is activated can be taken as the value indicative of atmospheric pressure, since in fact container 30 and tube 52 are in fluid contact both with the atmosphere and transducer 70. Or alternatively, while container 30 is still at atmospheric pressure because the container is still at separation dimension Y, piston 60 is moved from the solid position shown as "A", FIG. 2, to the first dotted position shown as "B" to generate a partial vacuum that is sufficient, if liquid were interfaced with aperture 34 of container 30, to generate a signal indicative of equilibrium pressure of such liquid. (As used herein, "equilibrium" refers to the liquid meniscus formed in the apparatus being stationary.) The partial vacuum so generated is used to generate a reference signal from transducer 70 that is indicative of no liquid having been encountered, since the first test is by definition at atmospheric pressure. Next, motor 44 is activated to advance container 30 a fraction Y' of dimension Y, for example 24% of that dimension. Practically, Y'/Y is between about 1/5 and 1/3. Motor 44 is stopped by control means 80, and motor 64 activated again to move piston 60 from position B to position C. The amount of partial vacuum so generated need not be, but preferably is, the same as in moving from position A to B. A signal is again produced by transducer 70, and that signal is compared to the reference signal previously generated. If there is no difference greater than a predetermined threshhold amount (to accommodate noise), then the liquid meniscus M still has not been penetrated. This is represented by container position 30', FIG. 2.
The aforementioned incremental advance of the probe, followed by a fractional partial vacuum being drawn by the piston, is repeated until either (a) a transducer signal is generated at a new level that exceeds the predetermined threshhold value, thus indicating the penetration of meniscus M (container 30" in FIG. 2), or (b) the increments advanced exceed a safety factor, m. That is, eventually piston 60 will advance to position X in chamber 62, and insufficient withdrawal of the piston will remain to permit aspiration of the liquid once the liquid is encountered. To prevent this from happening, if the liquid is not sensed after a prescribed number of attempts, either piston 60 is reset to its position A or the probe is lowered the remaining portion of dimension Y presumed to be effective to penetrate the liquid at its nominal level. The use of a transducer signal that exceeds the threshhold value to sense the liquid penetration is based upon the known principle that the resistance of a column of liquid to a partial vacuum is significantly different than the resistance provided by air.
By way of further explanation, the partial vacuum needed to sense for liquid penetration, that is, that which is sufficient to generate a signal indicative of the equilibrium pressure of any present liquid, depends upon a number of well-known factors which include: the dimensions of container aperture 34, the surface tension of the liquid, the contact angle at the liquid-container interface, and the corners encountered by the liquid entering the container. The measurement of the pressure is also affected by the presence of a transient and a steady state component. The transient component has a decreasing pressure profile with a time constant that is a function of the liquid viscosity and of the resistance to flow of the liquid within aperture 34. The amplitude of the transient will be a function of the ratio of the change in volume to the total internal air volume. The maximum value of the steady state component will be a function of the contact angle at the liquid-container interface and the internal radius of the container opening at such interface. The contact angle is a characteristic of the liquid/container material combination. The more hydrophobic the material of the container, the greater the contact angle and the greater the equilibrium pressure generated by the presence of liquid in aperture 34. Preferably, the pressure measurment is made at a time, after the volume change, which is selected to give the most consistent readings for the variety of liquids to be encountered by the dispensing apparatus. With hydrophobic container materials, most liquids will produce a large, stable equilibrium pressure reading. Liquids with low contact angles may be read shortly after the volume change at a time much longer than the settling time of the air component of the transient but well before the end of the liquid component of the transient.
It will be readily evident that more than the vacuum needed to produce an "indicative" signal can be used, but that such excessive vacuums are less desirable because, (a), they use up more of the pump volume, and (b) they tend to produce a longer transient signal. For most biological liquids of interest, the partial vacuum sufficient to produce the indicative signal is a fraction only of the operative partial vacuum used to initiate aspiration. For a particular set of container and liquid parameters, it has been found, for example, that the partial vacuum to produce the "indicative" signal occurs at about 1/5 the level of vacuum used to initiate aspiration of the liquid into that container. As used herein, "indicative" means, capable of being detected as an unambiguous event.
When the transducer signal indicates liquid penetration, motor 44 is activated one more time, to prepare container 30 for aspiration. Specifically, the motor advances aperture 34 of container 30 further (distance Y") into the liquid to position Z. The amount of advance is the amount needed to be certain that, during aspiration, aperture 34 still remains below meniscus M. Otherwise, there could be insufficient liquid above aperture 34 to be certain the liquid is aspirated without any air bubbles.
Thereafter, piston 60 is withdrawn to position X, FIG. 2, causing aspiration of the liquid into the container.
Probe 40 is then vertically withdrawn from container 20 and car 48 pulled back so that container 30 is vertically aligned with, e.g., a test element E held by suitable holding means 96, FIG. 1. Container 30 is then lowered until the liquid can be dispensed onto the test element. Dispensing occurs from the operative partial pressure generated by moving piston 60 from position X toward position A, preferably in 10 μl steps, each step for a separate test element.
The procedure of activating the piston to sense for liquid only when container 30 is not advancing, is preferred because the sensing of the liquid penetration is more complex if done while container 30 is advancing towards the liquid.
FIG. 4 is a representative signal produced by a transducer 70 when practicing the invention. In this case, only fractional partial vacuums were used to sense for the penetration event, that is, piston 60 was moved stepwise away from position A towards position X. Container 30 was constructed in accordance with U.S. Pat. No. 4,347,875, issued Sept. 7, 1982, with an inside diameter of aperture 34 that was about 500 μm. In the trace, time t 1 represents the time at which the voltage signal was read while the container was at atmospheric pressure, to establish a reference value R. Or alternatively, that value can be read at time t 3 , the steady state condition after the first partial vacuum is taken by moving at time t 2 piston 60 from position A to position B. The trace indicates a slight transient change in pressure when piston 60 moves at time t 2 . The microprocessor 82 subtracted from voltage R a predetermined threshhold value ΔV, here about 100 mv. The threshhold value ΔV was set to exceed the transient portions of the signal noted above. Additionally, it also was set to exceed the noise created by pressure changes arising from extraneous events. For a test signal to be representative of the condition of air-liquid interface penetration, this ΔV had to be exceeded. At time t 3 , motor 44 was activated to move container 30 an incremental distance Y' towards the liquid. At time t 4 , piston 60 was moved to position C, and in fact the signal dropped well beyond the threshhold value ΔV, indicating penetration had occurred. Preferably, the steady state value V 2 is read at time t 6 , as in FIG. 4, but with the proper selection of ΔV, the increasing signal producing at time t 5 a transient value V 1 is also useful. That is, any value V 1 that negatively exceeds ΔV can be used to trigger the event of liquid penetration. After time t 6 , probe 40 advanced the preset distance Y" described above, and at time t 7 , aspiration commenced.
The rate at which the condition of aperture 34 is sensed, and the rate of advance of probe 40 towards the liquid, are not critical, and are a function of the length of time available for a given sample test. By way of example, the total time for the iterative sensing of penetration and of moving the probe, up to the point where piston 60 is activated to aspirate the liquid, can be 800 millisec. Conventional stepper motors are available to cause the probe to advance in steps of 1/8" toward the liquid with each step taking only 100 millisec. The time needed to form a fractional partial vacuum or fractional partial pressure and to allow the transducer to generate a pressure signal is about 50 millisec. Thus, 5 such iterations can be done within the allotted 800 millisec. Alternatively, a longer time can be set aside with more or fewer iterations.
It will be appreciated that control means 80 is programmed or hard-wired to provide the timing described above. FIG. 5 is a flow chart that is useful in programming microprocessor 82, using conventional programming techniques. Specifically, the first step 105 is preferably to read the transducer signal while the container 30 is at atmospheric pressure, and storing the read value as reference R. The next step 110 is to move container 30 to an initial position at distance Y above the minimum level of liquid, FIG. 2, by activating motor 44. (Distance Y is subject to variations based upon the dimensions of container 20.) Such initial position is usually a location wherein container 30 has pierced the cap 24, FIG. 1, of the container. Next, step 115, S is set equal to 1. In step 120, motor 64 is activated (e.g., 12 half steps) to fractionally aspirate to generate a signal through the pressure sensing by the pressure transducer. If the reference R has not been read as step 105, then alternative step 125 is followed to obtain R. That is, the signal so generated by step 120 is selected, step 125, to be the reference signal ("R", FIG. 4) because it has been generated while the container is known to be at atmospheric pressure. If alternative step 125 is followed, then the program stores the reference value "R" and goes directly to step 140. Otherwise, step 130, the program tests to see if the liquid has been penetrated. If the answer is negative, then container 30 is ready to advance a distance Y', FIG. 2, if there remains a multiple greater than 1 of Y' left in the distance container 30 has to travel to completely traverse dimension Y. To test this, the microprocessor queries in step 140 the relationship Y-(S×Y')>Y'. If the answer is yes, the microprocessor further queries, step 150, whether m-S >0, where m is the maximum number of fractional aspirations, discussed above, that has been predetermined to be safe and still have sufficient volume left in chamber 62, FIG. 2, to do the operative aspiration of the liquid. For example, m can=4. If step 150 is answered yes, then motor 44 is activated, step 160, to advance container 30 a distance Y' (for example by advancing 66 half-steps). The loop then returns to step 120 via step 170 for the next iteration of the process.
Returning to step 130, if that query is answered in the positive, then the program exits from the aforedescribed loop. Preferably, an additional step 180 is included to advance container 30 a distance Y" to position Z, FIG. 2, prior to aspiration, as described above, to prevent air bubbles from being drawn in during aspiration.
The other route out of the loop occurs if the query of either step 140 or 150 is answered in the negative. The loop is exited and a preferred additional step 180' is to advance or move container 30 the remaining portion of distance Y to position it at a location presumed to penetrate the liquid at a depth that insures aspiration will occur without drawing in air bubbles.
Alternatively, step 180 can be modified to occur in stages as part of the aspiration routine which follows. That is, the aspiration step can proceed fractionally with further fractional advances of the container into the liquid. Thus, the aspiration can proceed by motor 64 and piston 60 withdrawing a portion only of the desired liquid, e.g., for 10 half-steps, followed by motor 44 advancing container 30 by a small amount, e.g., 1 half-step. Then, motor 64 withdraws piston 60 another 10 half-steps, and motor 44 advances 1 half-step etc., until all of the required liquid has been aspirated. As will be readily apparent, the amount of advance of container 30 is adjusted per amount of aspiration, based upon the diameter of container 20, to be sure aperture 34 of container 30, FIG. 2, is kept below meniscus M.
Alternatively, step 180' can be modified, when exiting from step 150 only, so that, instead of moving container 30 the remaining distance, piston 60 is reset to its initial position, e.g., position A, and sensing continues as described above. (S is reset to 1.)
Other than as noted above, the aspiration routine following liquid sensing is conventional.
As noted above, sensing for liquid penetration while container 30 continues to advance introduces additional complexities. However, although not preferred, the invention can still be practiced by repeated sensing for liquid at spaced intervals, while still moving container 30 toward the liquid. In that case, it is possible the liquid will be penetrated after a portion of the partial vacuum has already been dissipated while still in air, producing therefore a smaller negative steady-state signal response V 2 , FIG. 4. Such value V 2 might be less negative than (R-ΔV). In that case, the sensing protocol should be modified to either (a) use the transient value V 1 that exceeds the threshhold ΔV, or (b) reduce the threshhold value ΔV.
In yet another alternative, the pressurizing means can be operated so as to alternate between pressurizing and aspirating, to sense whether the liquid meniscus M has been penetrated. In such an embodiment, after the reference signal is generated by piston 60 moving to position B from position A, and probe 40 has been lowered one increment of distance Y, piston 60 is returned to position A rather than being moved to position C, FIG. 2. This acts to generate a fractional partial pressure in container 30 which forces air out of aperture 34. The signal generated by transducer 70 in the case where no liquid is encountered by the expelled air is different (at a lower voltage level) than the signal that occurs when the air has to be forced out into liquid. This alternative has the advantage that piston 60 automatically resets back to position A after every other incremental advance of the probe, so that no special resetting is necessary after a large number (m) of failures to detect the interface. It has the disadvantage, however, of potentially bubbling air into the sample liquid, if the penetration occurs before the half cycle when a partial pressure, rather than a partial vacuum, is used to generate the test signal. It has been found that even a slight bubbling of air into the test liquid is unsatisfactory in certain analyses as it can alter the level of an analyte of interest.
In still another alternative embodiment, piston 60 is operated to generate only fractional partial pressures to sense for the presence of the liquid. In such an embodiment, piston 60 preferably starts at an intermediate position such as position C, and incrementally advances to position A. If the liquid is still not sensed, piston 60 is reset to the first position, say position C, or the probe is moved the remaining portion of dimension Y where it will have penetrated the liquid.
In still another alternative embodiment, the reference signal produced for comparison with the signal sensing whether penetration has occurred or not, is produced while the dispensing container has its dispensing aperture immersed in a reference liquid. The signal so produced is stored in the microprocessor and a ΔV threshhold is added thereto, to represent the signal that is indicative of the dispensing container at atmospheric pressure. That is, any signal produced that is more positive than the value produced by adding ΔV, is indicative that the air-liquid interface has not yet been penetrated by the dispensing container.
It will be appreciated that the aforedescribed methods allow the detection of the penetration of the liquid by container 30, so that subsequent aspiration occurs with a minimum of exterior wetting of the container. This in turn minimizes the possibility of perfusion.
The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
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Apparatus and a method are described which permit the detection of penetration of liquid by an apertured container used for aspirating and dispensing the liquid. The apparatus and method feature control means for advancing the container an increment of the maximum possible distance to the liquid; generating a pressure differential within the dispensing container that is sufficient to generate a signal that is indicative of whether the container aperture is closed by the liquid; detecting and signalling the pressure produced within the container by such a pressure differential; and comparing such signalled pressure against a reference value determinative of whether the container has penetrated the liquid.
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TECHNICAL FIELD
[0001] This invention relates to a method for preparing p-xylene and co-producing propylene with a high selectivity from toluene and methanol and/or dimethyl ether, and pertains to the fields of chemistry and chemical industry.
BACKGROUND ART
[0002] P-xylene (hereinafter referred to as PX) and propylene are both important and valuable raw materials essential for chemical industry. At present, p-xylene is mainly obtained by an aromatic hydrocarbon combination apparatus. A reformate containing aromatic hydrocarbons is prepared by continuous reforming of naphtha, and a PX product is then maximally obtained via units of aromatic extraction, aromatic fractional distillation, disproportionation and transalkylation, xylene isomerization, and adsorptive separation, etc.
[0003] Since the content of p-xylene among three isomers is thermodynamically controlled, and p-xylene comprises only about 23% in C 8 mixed aromatic hydrocarbons, the amount of recycling process is large, equipment is bulky, and the operational cost is high during the whole PX production process. Particularly, the differences between boiling points of three isomers of xylene are very small, high-purity p-xylene cannot be obtained with typical distillation techniques, and an expensive process for adsorptive separation has to be used. Propylene is mainly derived from byproducts in petroleum refineries and also from the production of ethylene by steam cracking of naphtha, or is produced by using propane as a raw material, which is prepared by processing of natural gas. p-Xylene is mainly used in the production of polyesters, and propylene is extremely useful in the preparation of polypropylene and acrylonitrile as well as 1,3-propylene glycol required in the production of polyesters. The rapid development of the global economy increasingly demands for p-xylene and propylene as essential chemical feedstock.
[0004] In recent years, there are a number of domestic and foreign patents that disclose new routes for the production of p-xylene, and among these, methylation of toluene may produce p-xylene with a high selectivity. U.S. Pat. No. 3,965,207 discloses that a ZSM-5 molecular sieve is used as a catalyst to perform methylation reaction of toluene, wherein the highest selectivity of p-xylene at a reaction temperature of 600° C. is about 90%; U.S. Pat. No. 3,965,208 uses a ZSM-5 molecular sieve modified with VA element as a catalyst, and the generation of m-xylene is inhibited and p-xylene and o-xylene are mainly generated, wherein the highest selectivity of p-xylene at a reaction temperature of 600° C. is about 90%; U.S. Pat. No. 4,250,345 uses a ZSM-5 molecular sieve modified with two elements phosphorus and magnesium as a catalyst, wherein the optimal selectivity of p-xylene at a reaction temperature of 450° C. is up to 98%; U.S. Pat. No. 4,670,616 prepares a catalyst by using a borosilicate molecular sieve and silicon oxide or aluminum oxide, wherein the selectivity of p-xylene is 50-60%; U.S. Pat. Nos. 4,276,438, and 4,278,827 use a molecular sieve having a special structure (SiO 2 /Al 2 O 3 ≧12), which is modified with copper, silver, gold, germanium, tin, lead, etc., and a p-dialkylbenzene with a high selectivity can be obtained. U.S. Pat. No. 4,444,989 uses a crystalline pure silicon molecular sieve, which is modified with compounds of arsenic, phosphorus, magnesium, boron and, tellurium, and the selectivity of p-xylene is improved. U.S. Pat. No. 4,491,678 uses combined components of a crystalline borosilicate and elements of Group IIA and IIIA as well as silicon and phosphorus, and the selectivity of p-xylene may be greatly improved and the service life of the catalyst can be improved. U.S. Pat. No. 5,034,362 uses ZSM-5 and ZSM-11 wherein SiO 2 /Al 2 O 3 ≧12 as catalysts and performs calcination under a condition of higher than 650° C., and the selectivity of p-dialkylbenzenes may be improved. U.S. Pat. No. 5,563,310 uses an acidic molecular sieve containing an element of Group IVB, which is modified with a metal of Group VIB, and the selectivity of p-dialkylbenzenes in alkylation reaction of toluene and methanol may be improved. U.S. Pat. No. 6,504,072 uses a mesoporous molecular sieve, preferably ZSM-5, which is treated in steam higher than 950° C. and then modified with phosphorus oxides, and proposes the influence of the diffusion effect of catalyst micropores on the selectivity of p-xylene. U.S. Pat. No. 6,613,708 uses an organic metal compound to modify a catalyst, and the selectivity of p-dialkylbenzenes may be greatly improved.
[0005] Chinese Patents ZL200610011662.4, ZL200710176269.5, ZL 200710176274.6, ZL 200710179408.X, ZL 200710179409.4, and ZL 200710179410.7 disclose a class of methods for preparing p-xylene and co-producing light olefins from toluene and methanol, indicating that ethylene and propylene may be co-produced with a high selectivity at the same time of preparing p-xylene with also a high selectivity, wherein the selectivity of p-xylene in xylene isomers is up to 99 wt % or more and the selectivities of ethylene and propylene in C 1 -C 5 light hydrocarbons may be 90 wt % or more. However, the disadvantages of this method are that a cryogenic separation technique has to be used if a highly pure ethylene product is to be obtained, and that the investment and energy consumption are both high, which directly affects the economy of this process.
[0006] CN102464549 A discloses a method for producing propylene and p-xylene, comprising preparing propylene by the comproportionation of ethylene and C4 hydrocarbons, wherein the process for preparing propylene by the alkylation of ethylene and methanol/dimethyl ether is not involved. CN102464550 A discloses a method for co-production of light olefins and p-xylene, comprising preparing olefins by passing C4 and C5 hydrocarbons into a first reaction zone, which is a process of preparing olefins by cracking of C 4 or liquefied gas, wherein the process for preparing propylene by the alkylation of ethylene and methanol/dimethyl ether is not involved either.
SUMMARY OF THE INVENTION
[0007] An object of this invention is to provide a method for preparing p-xylene and co-producing propylene with a high selectivity from toluene and methanol and/or dimethyl ether.
[0008] To this end, this invention provides a method for preparing p-xylene and co-producing propylene with a high selectivity, comprising the steps of:
[0009] a) bringing a raw material containing toluene and methanol and/or dimethyl ether into contact with a catalyst in a reaction system for reaction, returning an ethylene-enriched C 2 − component discharged from the reaction system to the reaction system, and continuing the reaction with the raw material on the catalyst to produce propylene;
[0010] b) separating a C 6 + component discharged from the reaction system to obtain a product p-xylene; and
[0011] c) separating a C 3 component discharged from the reaction system to obtain a product propylene.
[0012] Preferably, the catalyst is a modified zeolite molecular sieve catalyst, which is obtained from ZSM-5 and/or ZSM-11 zeolite molecular sieves by hydrothermal treatment and surface modification of a siloxanyl compound. More preferably, in the modified zeolite molecular sieve catalyst, the amount of Si loaded by siloxanyl compound modification is 1-10 wt % based on the total weight of the modified zeolite molecular sieve catalyst.
[0013] In one preferred embodiment, the reaction system comprises a first reaction zone and a second reaction zone, and the method comprises the steps of:
[0014] a) passing a raw material containing toluene and methanol and/or dimethyl ether through the first reaction zone to be in contact with a catalyst I for reaction, and then into the second reaction zone to be in contact with a catalyst II for reaction; returning an ethylene-enriched C 2 − component discharged from the second reaction zone to the second reaction zone, and continuing reaction with methanol and/or dimethyl ether within the second reaction zone on the catalyst II to produce propylene;
[0015] b) further separating a C 6 + component discharged from the second reaction zone to obtain a product p-xylene; and
[0016] c) further separating a C 3 component discharged from the second reaction zone to obtain propylene.
[0017] In one preferred embodiment, the reaction system comprises a first reaction zone and a second reaction zone, and the method comprises the steps of:
[0018] a) passing a raw material containing toluene and methanol and/or dimethyl ether through the first reaction zone to be in contact with a catalyst I for reaction to obtain a resultant A, and then passing through the second reaction zone to be in contact with a catalyst II for reaction to obtain a resultant B; passing an ethylene-enriched C 2 − component in the resultant A and the resultant B into the second reaction zone, and continuing reaction with methanol and/or dimethyl ether within the second reaction zone on the catalyst II to produce propylene;
[0019] b) further separating a C 6 + component in the resultant A and the resultant B to obtain a product p-xylene; and
[0020] c) further separating a C 3 component in the resultant A and the resultant B to obtain a product propylene.
[0021] In one preferred embodiment, the catalyst I and the catalyst II are the same or different modified zeolite molecular sieve catalyst(s).
[0022] In one preferred embodiment, the modified zeolite molecular sieve catalyst is obtained from ZSM-5 and/or ZSM-11 zeolite molecular sieves via hydrothermal treatment and modification of a siloxanyl compound.
[0023] In one preferred embodiment, in the modified zeolite molecular sieve catalyst, the amount of Si loaded by siloxanyl compound modification is 1-10 wt % based on the total weight of the modified zeolite molecular sieve catalyst.
[0024] In one preferred embodiment, the conditions for the hydrothermal treatment are treating under an atmosphere of saturated steam at 500-700° C. for 3-6 hours.
[0025] In one preferred embodiment, the siloxanyl compound used in the siloxanyl compound modification has a structural formula as shown by the following formula:
[0000]
[0026] wherein R 1 , R 2 , R 3 , and R 4 are each independently a C 1-10 alkyl group.
[0027] In one preferred embodiment, the siloxanyl compound is tetraethyl orthosilicate.
[0028] In one preferred embodiment, the reaction zone comprises a reactor or a plurality of reactors connected in series and/or in parallel; and preferably, the reactor is one or more selected from a fixed bed reactor, a fluidized bed reactor, and a moving bed reactor.
[0029] In one preferred embodiment, the first reaction zone and the second reaction zone are in the same reactor; and preferably, the reactor is one or more selected from a fixed bed reactor, a fluidized bed reactor, and a moving bed reactor.
[0030] In one preferred embodiment, the first reaction zone comprises a reactor or a plurality of reactors connected in series and/or in parallel; the second reaction zone comprises a reactor or a plurality of reactors connected in series and/or in parallel; and the first reaction zone and the second reaction zone are connected in series or in parallel; and preferably, the reactor is one or more optionally selected from a fixed bed reactor, a fluidized bed reactor, and a moving bed reactor.
[0031] The advantageous effects of this invention include, but are not limited to, the following aspects: this invention provides a new method for preparing p-xylene and co-producing propylene with a high selectivity via the reaction of toluene and methanol and/or dimethyl ether. In the method of this invention, a specific modified molecular sieve catalyst is used, an ethylene-enriched C 2 − component in resultant products is returned to the reaction system and subjected to an alkylation reaction with methanol and/or dimethyl ether to further produce propylene, and p-xylene and propylene are finally obtained with a high selectivity. On one hand, high cost for separation of the ethylene product is avoided, and on the other hand, the production of propylene product with larger market demand may be further increased, such that the economy of this technique may be effectively improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a flow chart of a method of an embodiment according to this invention.
[0033] FIG. 2 is a flow chart of a method of another embodiment according to this invention.
[0034] FIG. 3 is a flow chart of a method of another embodiment according to this invention.
[0035] FIG. 4 is a flow chart of a method of another embodiment according to this invention.
DESCRIPTION OF EMBODIMENTS
[0036] In the method of this invention, two reaction processes, an alkylation reaction of toluene and methanol and/or dimethyl ether and an alkylation reaction of ethylene with methanol and/or dimethyl ether are coupled, meanwhile p-xylene and propylene are co-produced with a high selectivity. Specifically, a reaction process flow of the method of this invention is as shown in FIG. 1 . Toluene and methanol and/or dimethyl ether as raw materials are brought into contact with a catalyst (the catalyst is present in a reactor) in a reaction system, and resultant products are passed into a separation system (for example, a fractionating tower, etc.) for separation; after separation by a separation system, a C 6 + component, a C 4 -C 5 component (hydrocarbons having carbon numbers of 4 and 5), a C 3 component, an ethylene-enriched C 2 − component, and water (H 2 O) are obtained, wherein, the ethylene-enriched C 2 − component is returned to the reaction system, the C 6 + component is subjected to further separation (for example, a rectification column, a crystallization separation system, etc.) to obtain p-xylene, the C 3 component is subjected to further separation (for example, a rectification column, etc.) to obtain propylene, and a small amount of the C 4 -C 5 component and H 2 O are collected and used for other purposes, where the reaction system may be a separate reaction zone, or may be a combination of two or more reaction zones. A plurality of reaction zones may be in the same reactor, or may be in a plurality of reactors connected in series or in parallel. Preferably, the reactor is any one or more of a fixed bed, a fluidized bed, or a moving bed.
[0037] In this invention, the raw materials include toluene and methanol and/or dimethyl ether, indicating that the raw materials may be a mixture of toluene, methanol, and dimethyl ether, a mixture of toluene and methanol, or a mixture of toluene and dimethyl ether. Suitable kinds and compositional ratios of raw materials may be selected by the person skilled in the art according to requirements of actual production.
[0038] In one preferred embodiment, a reaction process flow of a method according to this invention is as shown in FIG. 2 . In FIG. 2 , the reaction system is composed of one reactor having two reaction zones, wherein the main reaction in the first reaction zone is alkylation reaction of toluene and methanol and/or dimethyl ether, and the main reaction in the second reaction zone is alkylation reaction between ethylene (a byproduct of the first reaction zone) and methanol and/or dimethyl ether. Toluene and methanol and/or dimethyl ether as raw materials are passed through the first reaction zone to be in contact with a catalyst I therein for reaction, and then passed through the second reaction zone to be in contact with a catalyst II therein for reaction, and resultant products are passed into a separation system for separation; a C 6 + component, a C 4 -C 5 component, a C 3 component, a C 2 − component, and H 2 O are obtained after separation by a separation system, wherein the ethylene-enriched C 2 − component is returned to the second reaction zone and subjected to reaction with methanol and/or dimethyl ether that are passed into the second reaction zone in contact with the catalyst II therein; the C 6 + component is subjected to further separation to obtain p-xylene, and the C 3 component is subjected to further separation to obtain propylene.
[0039] In one preferred embodiment, a reaction process flow of a method according to this invention is as shown in FIG. 3 . In FIG. 3 , the reaction system is composed of two parallel reaction zones, wherein the main reaction in the first reaction zone is alkylation reaction of toluene and methanol and/or dimethyl ether, and the main reaction in the second reaction zone is alkylation reaction between ethylene (a byproduct of the first reaction zone) and methanol and/or dimethyl ether. Toluene and methanol and/or dimethyl ether are brought into contact with a catalyst I in a first reaction zone to generate a resultant A, and the resultant A is passed into a separation system for separation; an ethylene-enriched C 2 − component from the separation system is returned to a second reaction zone and reacts with methanol and/or dimethyl ether as raw materials that are directly passed into the second reaction zone on a catalyst II therein to generate a resultant B, and the resultant B is passed into a separation system for separation together with the resultant A; after separation by the separation system, the ethylene-enriched C 2 − component therein is returned to the second reaction zone, a C 6 + component, which is obtained after the resultant A and the resultant B are separated by a separation system, is subjected to further separation to obtain p-xylene, and the C 3 component is subjected to further separation to obtain propylene.
[0040] In one preferred embodiment, a reaction process flow of a method according to this invention is as shown in FIG. 4 . In FIG. 4 , the reaction process is the same as the above process described for FIG. 3 , except that the reaction system is composed of two reaction zones in the same reactor, and verbose words are omitted herein. This reaction system may be achieved by multi-sectional feeding.
[0041] In this invention, the catalyst used contains ZSM-5 and/or ZSM-11 zeolite molecular sieves, more preferably modified ZSM-5 and/or ZSM-11 zeolite molecular sieves obtained from ZSM-5 and/or ZSM-11 zeolite molecular sieves by hydrothermal treatment and modification of the surface acidity and the pore structure with a siloxanyl compound. Most preferably, after modification with a siloxanyl compound, the loading amount of Si is 1-10 wt % based on the total weight of this catalyst. When there are two reaction zones, the catalyst I and the catalyst II present therein respectively may be catalysts having the same or component(s). For example, in one preferred embodiment, the catalyst I and the catalyst II are the same kind of catalysts or the same catalyst.
[0042] In one preferred embodiment, the preparation process for the catalyst used in this invention is as follows.
[0043] (1) ZSM-5 and/or ZSM-11 zeolite molecular sieve raw powders are prepared into acidic zeolite molecular sieves by NH 4 + ion exchange and calcination;
[0044] (2) the above acidic zeolite molecular sieves are subjected to hydrothermal treatment to obtain modified zeolite molecular sieves. Preferably, the condition of the hydrothermal treatment is treating under an atmosphere of saturated steam at 500-700° C. for 3-6 hours.
[0045] (3) the above modified zeolite molecular sieves are subjected to a surface modification by using a siloxanyl agent to further adjust the outer surface acidity and the pore structure of the molecular sieves so as to obtain modified zeolite molecular sieve catalysts.
[0046] Preferably, the siloxanyl compound used in this invention has a formula as shown by the following formula:
[0000]
[0047] wherein R 1 , R 2 , R 3 , R 4 are each independently a C 1-10 alkyl group, such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and a octyl group, as well as isomeric forms thereof.
[0048] Preferably, the siloxanyl compound used is tetraethyl orthosilicate.
[0049] Preferably, in either the first reaction zone or the second reaction zone in this invention, a fixed bed reaction process may be used, meanwhile a fluidized bed or moving bed reaction process in conjunction with a regenerator may be used. The first reaction zone and the second reaction zone may be respectively in one reactor or a plurality of reactors connected in series or in parallel, being the same or different, and are achieved by multi-sectional feeding.
[0050] In the method of this invention, the reaction temperature of alkylation of toluene and methanol and/or dimethyl ether, the reaction temperature of alkylation of ethylene and methanol and/or dimethyl ether are in the range 300-600° C. The reaction temperature of alkylation of toluene and methanol and/or dimethyl ether is preferably 400-500° C., and the preferred reaction temperature of alkylation of ethylene and methanol and/or dimethyl ether is 350-450° C. The mass hourly space velocity of alkylation reaction of toluene and methanol and/or dimethyl ether is 0.1-10 h −1 , and preferably 1-5 h −1 , in terms of toluene.
[0051] As for the method of this invention, in alkylation reaction of toluene and methanol and/or dimethyl ether, the feed molar ratio of toluene to methanol and/or dimethyl ether may be in a range of 0.1-10, preferably 0.2-5; and in alkylation reaction of ethylene and methanol and/or dimethyl ether, the molar ratio of ethylene to methanol and/or dimethyl ether may be in a range of 0.1-10, preferably 0.5-5.
[0052] Furthermore, in the method of this invention, the ratio of p-xylene to propylene in products can be controlled in a certain range by adjusting conditions such as the reaction temperature, the feed ratio of toluene to methanol and/or dimethyl ether, and the ratio of ethylene to methanol and/or dimethyl ether.
[0053] In this invention, the C 2 − component refers to a component of which the molecular formula has a carbon atom number less than or equal to 2, and includes ethylene, ethane, methane, CO, CO 2 , together with H 2 , etc. The purge gas is mainly ethane, methane, CO, CO 2 , together with H 2 , etc.
[0054] In this invention, the C 3 component refers to a compound of which the molecular formula has a carbon atom number equal to 3, and includes propylene, propane, etc.
[0055] In this invention, the C 4 -C 5 component refers to a component of which the molecular formula has a carbon atom number equal to 4 and 5, and includes isobutane, isobutene, butane, 1-butene, 2-butene, isopentane, neopentane, n-pentane, 1-pentene, 2-pentene, etc.
[0056] In this invention, the C 6 + component refers to a component of which the molecular formula has a carbon atom number greater than or equal to 6, and includes p-xylene and other aromatic hydrocarbons and derivatives thereof, etc.
[0057] This present invention will be described in detail below by Examples, but this invention is not limited to these Examples.
[0058] The composition of products is analyzed online by a gas chromatograph, and the analysis conditions are:
[0059] Model: Varian CP3800
[0060] Column: CP Wax 52 CB capillary chromatographic column
[0061] Carrier gas: helium gas, 5 ml/min
[0062] Temperature of column box: 60-220° C., programmed temperature increasing at 15° C./min
[0063] Temperature of feed port: 260° C.
[0064] Detector: hydrogen flame ionization detector (FID)
[0065] Temperature of detector: 300° C.
Example 1
[0066] Preparation of Catalysts: Si-HZSM-5 Zeolite Molecular Sieve Catalyst and Si-HZSM-11 Zeolite Molecular Sieve Catalyst
[0067] 500 g of ZSM-5 zeolite molecular sieve raw powder (SiO 2 /Al 2 O 3 =68) (Catalyst Plant of Fushun Petrochemical Company) and 500 g of ZSM-11 zeolite molecular sieve raw powder (SiO 2 /Al 2 O 3 =50) (Catalyst Plant of Nankai University) were calcined respectively at 550° C. to remove template agents, exchanged with 0.5 molar equivalents of an ammonium nitrate solution in a water bath at 80° C. for 4 times, dried at 120° C. in the air after exchange, and calcined at 550° C. for 4 hours so as to obtain a HZSM-5 zeolite molecular sieve and a HZSM-11 zeolite molecular sieve respectively.
[0068] The HZSM-5 zeolite molecular sieve and the HZSM-11 zeolite molecular sieve were modified by hydrothermal treatment respectively as follows: 100 g of each of the HZSM-5 zeolite molecular sieve and the HZSM-11 zeolite molecular sieve was placed in a quartz reactor respectively, water was introduced at a flow rate of 5 ml/min after the temperature was increased to 650° C., and a homothermal treatment was performed for 4 hours to obtain a hydrothermally modified HZSM-5 zeolite molecular sieve and a hydrothermally modified HZSM-11 zeolite molecular sieve. Surface modification was respectively performed on the hydrothermally modified HZSM-5 zeolite molecular sieve and HZSM-11 zeolite molecular sieve by using tetraethyl orthosilicate as a siloxane agent, and the steps were as follow: the hydrothermally modified HZSM-5 zeolite molecular sieve and HZSM-11 zeolite molecular sieve were respectively placed into 150 g of tetraethyl orthosilicate and soaked overnight, dried at 120° C. after liquid was decanted, and calcined in the air at 550° C. for 4 hours to obtain a modified Si-HZSM-5 zeolite molecular sieve catalyst and a hydrothermally modified Si-HZSM-11 zeolite molecular sieve catalyst respectively. They were named as catalysts TMPC-06 and TMPC-07.
Example 2
[0069] Preparation of catalysts: a mixed catalyst of Si-HZSM-5 and Si-HZSM-11 zeolite molecular sieves 200 g of ZSM-5 zeolite molecular sieve raw powder (SiO 2 /Al 2 O 3 =61) (Fushun Catalyst Plant) and 300 g of ZSM-11 zeolite molecular sieve raw powder (SiO 2 /Al 2 O 3 =50) were calcined at 550° C. to remove template agents, exchanged with 0.5 molar equivalents of an ammonium nitrate solution in a water bath at 80° C. for 4 times, dried at 120° C. in the air after exchange, and calcined at 550° C. for 4 hours so as to obtain a HZSM-5/HZSM-11 zeolite molecular sieve.
[0070] The HZSM-5/HZSM-11 zeolite molecular sieve was modified by hydrothermal treatment as follows: 100 g of the HZSM-5/HZSM-11 molecular sieve was placed in a quartz reactor, water was introduced at a flow rate of 5 ml/min after the temperature was increased to 650° C., and a homothermal treatment was performed for 4 hours to obtain a hydrothermally modified HZSM-5/HZSM-11 zeolite molecular sieve.
[0071] Surface modification was performed on the hydrothermally modified HZSM-5/HZSM-11 zeolite molecular sieve by using tetraethyl orthosilicate as a siloxane agent, and the steps were as follow: the hydrothermally modified HZSM-5/HZSM-11 zeolite molecular sieve was placed into 150 g of tetraethyl orthosilicate and soaked overnight, dried at 120° C. after liquid was decanted, and calcined in the air at 550° C. for 4 hours to obtain a modified Si-HZSM-5/HZSM-11 zeolite molecular sieve catalyst. It was named as catalyst TMPC-08.
Example 3
[0072] Preparation of p-Xylene and Co-Production of Propylene Via Reaction of Toluene with Methanol
[0073] According to the reaction process flow shown in FIG. 2 , catalyst samples of catalysts TMPC-06, TMPC-07, and TMPC-08 prepared in Examples 1 and 2 were subjected to tablet compression molding and 40-60 mesh target catalysts were obtained by cracking and sieving, each of the catalysts was charged to each of two reaction zones of a fixed bed reactor (10 g for each reaction zone). Conversion reaction of toluene and methanol was carried out in a first reaction zone, wherein the molar ratios of toluene/methanol can be seen in Table 1 below. Alkylation reaction of ethylene and methanol was carried out in a second reaction zone. When a reaction with a certain ratio therein was finished, nitrogen gas was introduced online for purging and then switched to air to regenerate the catalysts under a condition of 550° C. for 5 hours, where an ethylene-enriched C 2 − component and methanol in the reaction product distribution of alkylation of toluene and methanol in the first reaction zone were passed together into the second reaction zone for reaction, wherein the molar ratio of ethylene/methanol was 1/1.
[0074] Reaction conditions: in the first reaction zone, the mass hourly space velocity of toluene was 2 h −1 and the reaction temperature was 480° C.; in the second reaction zone, the reaction temperature was 420° C. The composition of mixed products in the reaction zones was analyzed online by using a gas chromatograph. The product distribution was as shown in Table 1 after resultant water was removed, and the product distribution was as shown in Table 2 after the C 2 − component was further removed.
[0075] It can be seen from the data of Table 2 that on catalysts TMPC-06, TMPC-07, and TMPC-08, when feed molar ratios of toluene/methanol were 2/1, 1/1, and 1/2 respectively, the selectivities of propylene in total products were 26.19 wt %, 31.75 wt %, and 41.28 wt % respectively, and the selectivities of p-xylene were 62.38 wt %, 56.66 wt %, and 45.45 wt % respectively; and the overall selectivities of propylene and p-xylene were 88.57 wt %, 88.41 wt %, and 86.73 wt % respectively. The selectivities of p-xylene in xylene isomers were 98.34 wt %, 98.15 wt %, and 97.63 wt % respectively.
[0000]
TABLE 1
Catalyst
TMPC-06
TMPC-07
TMPC-08
Feeding time (hour)
1
1
1
Toluene/methanol (molar
2/1
1/1
1/2
ratio) in the first reaction
zone
Ethylene/methanol
1/1
1/1
1/1
(molar ratio) in the
second reaction zone
Product distribution
(wt %*)
CH 4
0.91
1.09
1.38
C 2 H 4
11.51
13.80
19.01
C 2 H 6
0.29
0.21
0.24
C 3 H 6
22.86
26.96
32.76
C 3 H 8
0.52
0.55
0.58
C 4
1.44
1.96
2.69
C 5
0.57
0.71
0.89
Benzene
0.06
0.03
0.10
Ethylbenzene
0.21
0.15
0.19
p-Xylene
54.46
48.10
36.07
m-Xylene
0.34
0.25
0.32
o-Xylene
0.58
0.66
0.55
≧C 9
6.27
5.54
5.21
Total
100.00
100.00
100.00
*wt %, weight percentage composition of products, the same shall apply hereinafter.
[0000]
TABLE 2
Catalyst
TMPC-06
TMPC-07
TMPC-08
Feeding time (hour)
1
1
1
Toluene/methanol (molar
2/1
1/1
1/2
ratio) in the first reaction
zone
Ethylene/methanol
1/1
1/1
1/1
(molar ratio) in the
second reaction zone
Product distribution
(wt %)
C 3 H 6
26.19
31.75
41.28
C 3 H 8
0.59
0.65
0.74
C 4
1.64
2.30
3.38
C 5
0.65
0.83
1.12
Benzene
0.07
0.04
0.13
Ethylbenzene
0.24
0.18
0.24
p-Xylene
62.38
56.66
45.45
m-Xylene
0.39
0.30
0.41
o-Xylene
0.66
0.77
0.70
≧C 9
7.18
6.52
6.57
Total
100.00
100.00
100.00
Example 4
[0076] Preparation of p-Xylene and Co-Production of Propylene Via Reaction of Toluene with Methanol
[0077] According to the reaction process flow shown in FIG. 3 or 4 , a TMPC-06 catalyst prepared in Example 1 was subjected to tablet compression molding and a 40-60 mesh target catalyst sample was obtained by cracking and sieving, the catalyst was charged to each of two reaction zones of a fixed bed reactor (10 g for each reaction zone). Conversion reaction of toluene and methanol was carried out in a first reaction zone, wherein the molar ratios of toluene/methanol were 4/1, 2/1, 1/1, and 1/2 respectively (see Table 3 below). Alkylation reaction of ethylene and methanol was carried out in a second reaction zone, where an ethylene-enriched C 2 − component and methanol in the reaction product distribution of alkylation of toluene and methanol in the first reaction zone were passed together into the second reaction zone for reaction, wherein the molar ratio of ethylene/methanol was 1/1.
[0078] Once a reaction with a certain ratio therein was completed, nitrogen gas was introduced to both the first reaction zone and the second reaction zone online for purging, and then switched to air to regenerate the catalysts under a condition of 550° C. for 5 hours. The temperature was decreased with nitrogen gas purging to a reaction temperature for performing a conversion reaction of toluene and methanol with another ratio and alkylation reaction of ethylene and methanol. Other reaction conditions: in the first reaction zone, the mass hourly space velocity of toluene was 2 h −1 and the reaction temperature was 480° C.; in the second reaction zone, the reaction temperature was 400° C. The composition of a mixed product of the first reaction zone and the second reaction zone was analyzed online by using a gas chromatograph respectively. The product distribution was as shown in Table 3 after resultant water was removed, and the product distribution was as shown in Table 4 after the C 2 − component was further removed.
[0079] It can be seen from Table 4 that when feed molar ratios of toluene/methanol were 4/1, 2/1, 1/1, and 1/2 respectively, the selectivities of propylene in total products were 24.32 wt %, 27.64 wt %, 33.32 wt %, and 43.12 wt % respectively, and the selectivities of p-xylene were 67.18 wt %, 64.26 wt %, 58.51 wt %, and 47.35 wt % respectively; and the overall selectivities of propylene and p-xylene were 91.50 wt %, 91.90 wt %, 91.83 wt %, and 90.47 wt % respectively. The selectivities of p-xylene in xylene isomers were 99.31 wt %, 99.26 wt %, 99.21 wt %, and 99.14 wt % respectively.
[0000]
TABLE 3
Catalyst
TMPC-06
Feeding time (hour)
1
1
1
1
Toluene/methanol (molar ratio) in
4/1
2/1
1/1
1/2
the first reaction zone
Ethylene/methanol (molar ratio) in
1/1
1/1
1/1
1/1
the second reaction zone
Selectivity of p-xylene in xylene
99.31
99.26
99.21
99.14
isomers (wt %)
Product distribution (wt %)
CH 4
1.44
0.81
0.98
1.17
C 2 H 4
10.66
12.54
15.68
20.89
C 2 H 6
0.07
0.09
0.11
0.11
C 3 H 6
21.36
23.93
27.73
33.56
C 3 H 8
0.11
0.12
0.15
0.18
C 4
1.22
1.44
1.94
2.67
C 5
0.49
0.57
0.70
0.88
Benzene
0.14
0.06
0.03
0.10
Ethylbenzene
0.13
0.11
0.10
0.09
p-Xylene
59.00
55.62
48.70
36.85
m-Xylene
0.03
0.04
0.04
0.04
o-Xylene
0.38
0.38
0.35
0.28
≧C 9
4.97
4.29
3.48
3.18
Total
100.00
100.00
100.00
100.00
[0000]
TABLE 4
Catalyst
TMPC-06
Feeding time (hour)
1
1
1
1
Toluene/methanol (molar ratio) in
4/1
2/1
1/1
1/2
the first reaction zone
Ethylene/methanol (molar ratio) in
1/1
1/1
1/1
1/1
the second reaction zone
Selectivity of propylene +
91.50
91.90
91.83
90.47
p-xylene (wt %)
Selectivity of p-xylene in xylene
99.31
99.09
99.21
99.14
isomers (wt %)
Product distribution (wt %)
C 3 H 6
24.32
27.64
33.32
43.12
C 3 H 8
0.12
0.13
0.18
0.23
C 4
1.39
1.66
2.33
3.43
C 5
0.56
0.66
0.84
1.12
Benzene
0.16
0.07
0.04
0.13
Ethylbenzene
0.14
0.13
0.12
0.11
p-Xylene
67.18
64.26
58.51
47.35
m-Xylene
0.04
0.04
0.04
0.05
o-Xylene
0.43
0.44
0.42
0.36
≧C 9
5.66
4.96
4.18
4.09
Total
100.00
100.00
100.00
100.00
Comparative Example 1
[0080] Preparation of p-Xylene and Co-Production of Ethylene and Propylene Via Reaction of Toluene and Methanol without Further Reaction by Returning C 2 − Component
[0081] A TMPC-06 catalyst prepared in Example 1 was subjected to tablet compression molding and a 40-60 mesh target catalyst sample was obtained by cracking and sieving. 10 g of the catalyst was charged to a reactor for performing conversion reaction of toluene and methanol. Molar ratios of toluene/methanol were 4/1, 2/1, 1/1, and 1/2 respectively. Once a reaction with a certain ratio therein was completed, nitrogen gas was introduced online for purging and then switched to air to regenerate the catalysts under a condition of 550° C. for 5 hours. The temperature was decreased with nitrogen gas purging to a reaction temperature for performing a conversion reaction of toluene and methanol with another ratio. Other reaction conditions: the mass hourly space velocity of toluene was 2 h −1 and the reaction temperature was 480° C. The composition of products was analyzed online by using a gas chromatograph. The product distribution was as shown in Table 5 after resultant water was removed.
[0082] When feed molar ratios of toluene/methanol were 4/1, 2/1, 1/1, and 1/2 respectively, the selectivities of propylene in products were 2.93 wt %, 4.66 wt %, 7.89 wt %, and 13.17 wt % respectively.
[0000]
TABLE 5
Catalyst
TMPC-06
Feeding time (hour)
1
1
1
1
Toluene/methanol (molar
4/1
2/1
1/1
1/2
ratio) in the first reactor
Conversion rate of
100
100
94.36
90.23
methanol (%)
Conversion rate of
14.04
23.47
31.74
36.21
methanol toluene (%)
Selectivity of p-xylene in
99.35
99.46
99.23
99.16
xylene isomers (wt %)
Product distribution (wt %)
CH 4
0.11
0.18
0.30
0.49
C 2 H 4
4.92
6.58
10.34
17.52
C 2 H 6
0.01
0.01
0.02
0.02
C 3 H 6
2.93
4.66
7.89
13.17
C 3 H 8
0.04
0.07
0.11
0.15
C 4
0.39
0.65
1.07
2.06
C 5
0.25
0.27
0.43
0.64
Benzene
0.19
0.09
0.04
0.15
Ethylbenzene
0.17
0.16
0.14
0.13
p-Xylene
83.54
81.21
73.92
60.13
m-Xylene
0.02
0.02
0.05
0.06
o-Xylene
0.52
0.42
0.52
0.45
≧C 9
6.91
5.69
5.16
5.03
Total
100.00
100.00
100.00
100.00
[0083] This invention has been described in detail above, but this invention is not limited to specific embodiments described herein. It will be understood by the person skilled in the art that other modifications and variations can be made without departing from the scope of the invention. The scope of the invention is defined by the appended claims.
|
A method for preparing p-xylene and co-producing propylene with a high selectivity, comprising:
a) bringing a raw material containing toluene and methanol and/or dimethyl ether into contact with a catalyst in a reaction system for reaction; returning an ethylene-enriched C 2 − component discharged from the reaction system to the reaction system, and continuing the reaction with the raw material on the catalyst to produce propylene;
b) separating a C 6 + component discharged from the reaction system to obtain a product p-xylene; and
c) separating a C 3 component discharged from the reaction system to obtain a product propylene.
| 2
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control device for an internal combustion engine.
2. Description of the Related Art
Japanese Unexamined Patent Publication (Kokai) No. 2-169834 discloses an internal combustion engine wherein, during low load operation, the entire required amount of fuel injection is injected into the engine cylinders during the compression stroke to form an air-fuel mixture around the spark plugs, while during medium and high load operation, fuel is injected into the engine cylinders during the intake stroke to form an air-fuel premixture and fuel is injected into the engine cylinders during the compression stroke to form an air-fuel mixture for ignition near the spark plugs.
In this internal combustion engine, however, among the load regions in which the amount of fuel injection is divided between the intake stroke and the compression stroke, in the region of low load operation, the suitable ratio of the amount of fuel injection in the intake stroke and the amount of fuel injection in the compression stroke is limited to within a narrow range based on the engine operating state, so in this operating region, it is difficult to always obtain good combustion with a small amount of torque fluctuation.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a control device for an internal combustion engine by which the above problem can be solved.
According to the present invention, there is provided a control device for an internal combustion engine having cylinder and spark plug, the control device including a fuel feeding means for feeding fuel into the cylinder, feeding a part of an amount of fuel to be injected during an intake stroke to form an air-fuel premixture, and feeding the remaining part of the amount of fuel to be injected during a compression stroke to form an air-fuel mixture around the spark plug for ignition; a pressure detecting means for detecting pressure in the cylinder; a combustion state determining means for determining a combustion state in the cylinder on the basis of the pressure detected by the pressure detecting means; and a fuel feeding control means for controlling a ratio of the part of the amount of fuel to be injected to the amount of fuel to be injected on the basis of the result of determination of the combustion state determining means so that a good state of combustion is obtained.
The present invention may be more fully understood from the description of preferred embodiments of the invention set forth below, together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is an overall view of an internal combustion engine of an embodiment of the present invention;
FIG. 2 is a block diagram of an electronic control unit;
FIG. 3 is a longitudinal sectional view of a fuel injector;
FIG. 4 is a longitudinal sectional view of the engine of FIG. 2;
FIG. 5 is a graph of an example of a control pattern of injection in the compression stroke and injection in the intake stroke;
FIG. 6 is a graph of the timing of fuel injection;
FIGS. 7(a-d) are an explanatory view of the operation when injecting fuel in the intake stroke and the compression stroke;
FIG. 8 is a flow chart for calculating the amount of fuel injected in the intake stroke and the compression stroke;
FIG. 9 is a map of the amount of fuel injection Q based on the engine rotational speed Ne and QA/Ne;
FIG. 10 is a map of the rate of division QR based on the amount Q of fuel injection;
FIGS. 11A and 11B are flow charts for calculating a correction value KQR;
FIG. 12 is a graph of the relationship between the crank angle and the pressure in the cylinders;
FIG. 13 is a graph of the relationship between P 1r and P 2 ; and
FIG. 14 is a map of the reference cylinder pressure P 3 based on the amount of fuel injection Q and P 1r .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is an overall view of an internal combustion engine of an embodiment of the present invention. In FIG. 1, 1 is the engine body, 2 is a surge tank, 3 is an intake pipe extending from the surge tank 2 and 4 is a throttle valve provided in the middle of the intake pipe 3. The internal combustion engine also includes fuel injectors 5 for directly injecting fuel into the cylinders, 6 are spark plugs, 7 is a high pressure reserve tank, 8 is a high pressure fuel pump with a controllable discharge pressure for sending high pressure fuel under pressure through a high pressure conduit 9 to the reserve tank 7, 10 is a fuel tank, and 11 is a low pressure fuel pump for feeding fuel through a conduit 12 from the fuel tank 10 to the high pressure fuel pump 8. The discharge side of the low pressure fuel pump 11 is connected to a piezoelectric element cooling introduction pipe 13 for cooling the piezoelectric elements of the fuel injectors 5. A piezoelectric element cooling return pipe 14 is linked with the fuel tank 10. Fuel flowing through the piezoelectric element cooling introduction pipe 13 is returned to the fuel tank through this return pipe 14. Branch pipes 15 connect the high pressure fuel injectors 5 to the high pressure reserve tank 7.
A fuel pressure sensor 36 is attached to the high pressure reserve tank 7, which fuel pressure sensor 36 detects the fuel pressure inside the high pressure reserve tank 7. Based on the pressure detected by the fuel pressure sensor 36, the high pressure fuel pump 8 is controlled so that the fuel pressure inside the high pressure reserve tank 7 becomes the target fuel pressure. At the inlet of the intake pipe 3 is disposed an air flow meter 37 for detecting the amount of intake air QA.
FIG. 2 is a block diagram of the constitution of an electronic control unit 20. Referring to FIG. 2, the electronic control unit 20 is comprised of a digital computer. It is provided with a read only memory (ROM) 22, a random access memory (RAM) 23, a microprocessor (CPU) 24, an input port 25, and an output port 26 connected by a bidirectional bus 21.
The fuel pressure sensor 36 and the air flow meter 37 are connected to the input port 25 through the corresponding AD converters 30 and 31. A reference position sensor 28 which generates a reference position detection pulse signal with each 720 degrees crank angle and a crank angle sensor 38 which generates a crank angle detection signal with each 30 degrees crank angle are connected to the input port 25. Further, a cylinder pressure sensor 39 for detecting the absolute pressure inside the engine cylinders (see FIG. 4) is connected via the AD converter 32 to the input port 25.
On the other hand, the output port 26 is connected through the corresponding drive circuits 33 and 34 to the high pressure reserve tank 7 and the fuel injectors 5. Further, the output port 26 is connected through the drive circuit 35 to an ignitor 16. The ignitor 16 is connected through an ignition coil 17 to the spark plugs 6.
FIG. 3 shows a side sectional view of a fuel injector 5. Referring to FIG. 3, 40 is a needle inserted into a nozzle 50, 41 is a pressurizing rod, 42 is a movable plunger, 43 is a compression spring disposed inside a spring holding chamber 44 and pressing the needle 40 downward, 45 is a pressurizing piston, 46 is a piezoelectric element, 47 is a pressurizing chamber formed between the top surface of the movable plunger 42 and the piston 45 and filled with fuel, and 48 is a needle pressurizing chamber. The needle pressurizing chamber 48 is connected to the high pressure reserve tank 7 (FIG. 1) through a fuel passageway 49 and branch pipes 14 and therefore the high pressure fuel inside the high pressure reserve tank 7 is fed through the branch pipes 14 and the fuel passageway 49 to the inside of the needle pressurizing chamber 48. When the piezoelectric element 46 is charged, the piezoelectric element 46 elongates and thereby the fuel pressure inside the pressurizing chamber 47 is raised. As a result, the movable plunger 42 is pressed downward, and the nozzle opening 53 is held in a closed state by the needle 40. On the other hand, when the piezoelectric element 46 is discharged, the piezoelectric element 46 contracts and the fuel pressure in the pressurizing chamber 47 falls. As a result, the movable plunger 42 rises, so the needle 40 rises and the fuel is injected from the nozzle opening 53.
FIG. 4 is a longitudinal sectional view of the engine of FIG. 2. Referring to FIG. 4, 60 is a cylinder block, 61 is a cylinder head, 62 is a piston, 63 is a substantially cylindrical depression formed in the top surface of the piston 62, and 64 is a cylinder chamber formed between the top surface of the piston 62 and the walls in the cylinder head 61. The spark plug 6 is attached substantially at the center of the cylinder head 61 close to the cylinder chamber 64. While not shown in the figure, an intake port and exhaust port are formed in the cylinder head 61. At the opening of the intake port and exhaust port into the cylinder chamber 64 are disposed an intake valve 66 (see FIG. 7(a)) and an exhaust valve. The fuel injector 5 is a swirl type fuel injector, which injects mist-like fuel with a large dispersion angle and a weak penetrating force. The fuel injector 5 faces downward at a slant and is disposed at the top portion of the cylinder chamber 64. It is disposed so as to inject fuel toward the vicinity of the spark plug 6. The direction of fuel injection and the fuel injection timing of the fuel injector 5 are determined so that the injected fuel goes toward the depression 63 formed in the top portion of the piston chamber 62.
The internal combustion engine of this embodiment is a internal combustion engine able to divide the injection of the amount of fuel between the intake stroke and the compression stroke in accordance with the engine operating state. FIG. 5 shows the ratio of the amount of fuel injection in the intake amount to the amount of fuel injection in the compression stroke at a predetermined engine rotational speed. Referring to FIG. 5, the horizontal axis shows the load of the engine. In FIG. 5, the amount Q of fuel injection is taken as the load. The vertical axis also shows the amount Q of fuel injection.
When the amount of fuel injection showing the engine load is from the amount of fuel injection during idling Q I to the amount of fuel injection during medium load Q M , fuel is injected only in the compression stroke. The amount of fuel injection in the compression stroke Q C is gradually increased from the amount of fuel injection during idling Q I to the amount of fuel injection during medium load Q M . When the amount of fuel injection showing the engine load exceeds Q M , the amount of fuel injection during the compression stroke is rapidly reduced from Q M to Q D and the amount of fuel injection in the intake stroke is rapidly increased to Q P . Q M is the amount of fuel injection near the medium load and is shown by the following equation as the sum of Q D and Q P :
Q.sub.M =Q.sub.D +Q.sub.P
Here Q D is the minimum amount of fuel injection in the compression stroke which is able to form an air-fuel mixture ignitable by the spark plug 6 and is an amount smaller than the amount of fuel injection during idling Q I . Further, Q P is the minimum amount of fuel injection during the intake stroke enabling propagation of the flame ignited by the spark plug 6 when the fuel injected in the intake stroke is uniformly dispersed in the cylinder chamber 64. From the amount of fuel injection during medium loads Q M to the amount of fuel injection at high loads Q H , the amount of fuel injection is divided between the compression stroke and the intake stroke. The amount of fuel injection during the compression stroke does not depend on the engine load. It is made constant at Q D . The amount of fuel injection during the intake stroke is increased along with the increase of the engine load.
At times of very high loads when the engine load exceeds the amount of fuel injection at high loads Q H and reaches the maximum amount of fuel injection Q M , since the amount of fuel injection is large, the concentration of the air-fuel premixture in the cylinder chamber formed by the injection in the intake stroke is great enough for ignition, so the injection in the compression stroke for ignition purposes is foregone and the entire required amount of fuel injection is injected in the intake stroke. The amount of fuel injection during high loads Q H is the minimum amount of fuel injection in the intake stroke able to form a uniform air-fuel mixture which can be ignited by the spark plug even in the case where the fuel is uniformly dispersed in the cylinder chamber.
As shown in FIG. 6, the intake stroke means the period from the top dead center of the exhaust process to the bottom dead center of the intake process, while the compression stroke means the period from the bottom dead center of the compression process to the top dead center of the compression process.
The injection during the intake stroke is executed during the period shown by D I . This period D I corresponds to substantially the former half of the intake stroke. The injection during the compression stroke is executed in the period shown by D C . This period D C corresponds to substantially the latter half of the compression stroke. The fuel is injected in the period D I or D C , so the injected fuel does not directly strike the cylinder block 60, so almost none of the injected fuel adheres to the inside surface of the cylinder block 60.
In the region from near the medium load (amount of fuel injection Q M ) to the low load, as shown in FIG. 4, only the injection during the compression stroke is executed in the latter period of the compression stroke and fuel is injected from the fuel injector 5 toward the spark plug 6 and the depression 63 at the top surface of the piston 62. This injected fuel has a weak penetrating force. Further, the pressure in the cylinder chamber 64 is high and the flow of air is weak. Therefore, the injected fuel tends to concentrate at the region K near the spark plug 6. Since the distribution of fuel in the region K is uneven and changes from a rich air-fuel mixture layer to an air layer, there is a combustible air-fuel mixture layer near the stoichiometric air-fuel ratio which can be most easily burnt. Therefore, the combustible air-fuel mixture layer near the spark plug 6 is easily ignited and the ignited flame propagates throughout the uneven air-fuel mixture layer as a whole to complete the combustion. In this way, in the region from the medium load to the low load, the fuel is injected near the spark plug 6 in the latter period of the compression stroke, whereby a combustible air-fuel mixture layer is formed near the spark plug 6 and therefore excellent ignition and combustion can be obtained.
On the other hand, in the region from near the medium load (amount of fuel injection Q M ) to the high load, as shown in FIG. 7, the injection during the intake stroke is executed in the early period of the intake stroke (FIG. 7(a)) and fuel is injected from the fuel injector 5 toward the spark plug 6 and the depression 63 of the top surface of the piston 62. This injected fuel is mist-like fuel of a large dispersion angle and a weak penetrating force. Part of the injected fuel floats free in the cylinder chamber 64 and the rest strikes the depression 63. The injected fuel is dispersed in the cylinder chamber 64 by the disturbance T in the cylinder chamber 64 caused by the flow of intake air entering from the intake port to the cylinder chamber 64 and therefore an air-fuel premixture P is formed in the period from the intake stroke to the compression stroke (FIG. 7(b)). The air-fuel ratio of this air-fuel premixture P is an air-fuel ratio of an extent where the ignited flame can be propagated. Further, in the state of FIG. 7(b), since the extension of the center axial line of the injected fuel is oriented toward the cylinder chamber, if the penetrating force of the injected fuel is strong, part of the mist is liable to deposit directly on the cylinder walls. In this embodiment, there is no particular problem since the injection is performed with a relatively weak penetrating force, but in the embodiment of the present invention, the effect of prevention of deposition of fuel on the cylinder walls is enhanced by making this period a noninjection period. Next, at the latter period of the compression stroke (FIG. 7(c)), the injection at the compression stroke is executed and fuel is injected from the fuel injector 5 toward the vicinity of the spark plug 6 and the depression 63 in the top surface of the piston 6. Since the injected fuel is directed toward the spark plug 6 and further has a weak penetrating force and since the pressure inside the cylinder chamber 64 is large, the injected fuel tends to concentrate at the region K near the spark plug 6. The fuel in the region K is uneven in distribution and changes from a rich air-fuel mixture layer to an air layer, so there is a combustible air-fuel mixture layer near the stoichiometric air-fuel ratio, which is most easily burnt, in the region K. Therefore, when the combustible air-fuel mixture layer is ignited by the spark plug 6, combustion proceeds centered in the uneven air-fuel mixture region K (FIG. 7(d)). In this combustion process, the flame propagates successively to the air-fuel premixture P from near the expanded combustion gas B and the combustion is completed. In this way, by injecting fuel in the early period of the intake stroke in the medium load and high load region, an air-fuel mixture for flame propagation is formed the cylinder chamber 64 as a whole and by injecting fuel in the latter period of the compression stroke, a relatively thin air-fuel mixture is formed near the spark plug 6 and therefore an air-fuel mixture for ignition is formed.
In particular, if the entire required amount of injection is injected in the intake stroke or in the first half of the compression stroke in medium load operation as in a conventional engine, the injected fuel ends up dispersed in the cylinder chamber 64 as a whole, so the air-fuel mixture formed in the cylinder chamber 64 becomes too thin and there is the problem of difficult ignition and combustion. On the other hand, if the entire required amount of injection is injected in the latter period of the compression stroke in medium load operation, there are the problems that a large amount of smoke is produced and it is not possible to raise the rate of utilization of air, so a sufficiently high output cannot be obtained.
Therefore, as mentioned earlier, during medium load operation, injection is performed divided between the intake stroke and the compression stroke, so an excellent ignition and a high output due to combustion with a high rate of utilization of air are obtained.
Further, near the medium load, the uniform air-fuel mixture formed by the fuel injected in the intake stroke may have an air fuel ratio excellent for enabling flame propagation, which is thinner than an ignitable air-fuel ratio, so the fuel economy is improved by lean combustion.
In FIG. 5, however, in the period between the amounts of fuel injection Q M and Q H , that is, the load region where the required amount of fuel injection is divided between the intake stroke and the compression stroke, in the load region on the low load side, that is, in the load region near Q M , the suitable ratio of the amount of fuel injection during the intake stroke and the amount of fuel injection during the compression stroke is limited to a narrow range in accordance with the engine operating state, so there is the problem that it is difficult to always obtain an excellent combustion with a small amount of torque fluctuation in this load region.
Therefore, in this embodiment, the cylinder pressure in the engine cylinders is detected, the state of combustion is judged based on the cylinder pressure, and the ratio of the amount of fuel injection in the intake stroke and the amount of fuel injection in the compression stroke is changed based on this judgement so as to obtain excellent combustion.
FIG. 8 shows the routine for calculating the amount of fuel injection in the intake stroke and the compression stroke. This routine is executed by interruption every predetermined crank angle.
Referring to FIG. 8, first, at step 70, the required amount of fuel injection Q is found from a map (see FIG. 9) based on the engine rotational speed Ne and QA/Ne. Here, QA/Ne is the amount of intake air per rotation of the engine and expresses the engine load. Next, at step 71, the division rate QR is calculated based on the required amount of fuel injection Q. Here, the division rate QR is the ratio of the amount of fuel injection in the intake stroke Qs to the required amount of fuel injection Q.
The map of the required amount of fuel injection Q and the division rate QR is shown in FIG. 10. FIG. 10 corresponds to FIG. 5. QR is 0 when the required amount of fuel injection Q is from Q I to Q M . Therefore, the entire required amount of fuel injection Q is injected during the compression stroke. From Q M to Q H , injection is performed during the intake stroke and the compression stroke, with the ratio of the amount of fuel injection during the intake stroke increasing in accordance with an increase in the load. From Q H to Q W , QR becomes 1.0 and the entire required amount of fuel injection Q is injected in the intake stroke.
Referring again to FIG. 8, at step 72, it is determined if QR is equal to 0 or 1. When the division rate QR is not equal to 0 or 1, the routine proceeds to step 73, where the correction value KQR is added to QR. The correction value KQR is calculated by the routine shown in FIG. 11A and FIG. 11B, explained later.
At step 74, it is determined if QR is more than 0. If QR<0, the routine proceeds to step 75, where QR is made 0. On the other hand, if QR≧0, the routine proceeds to step 76, wherein it is determined if QR≦1. If QR>1, the routine proceeds to step 77, where QR is made 1. If QR≦1, the value of QR is held as it is.
At step 78, the amount of fuel injection in the intake stroke Q S is calculated by the following equation:
Q.sub.S =Q·QR
Next, at step 79, the amount of fuel injection of the intake stroke is subtracted from Q so as to calculate the amount of fuel injection during the compression stroke Q C .
If it is determined at step 72 that QR is 0 or 1, step 73 to step 77 are skipped and QR is not corrected, but is maintained as 0 or 1.
FIG. 11A and FIG. 11B show the routine for calculating the correction value KQR. This routine is executed by interruption every predetermined crank angle.
Referring to FIG. 11A and FIG. 11B, first, at step 90, it is determined if the crank angle 8 is the predetermined crank angle θ 1 (see FIG. 12).
FIG. 12 shows the relationship between the crank angle and the cylinder pressure. Referring to FIG. 12, the solid line shows the actual cylinder pressure when excellent combustion is achieved, the broken line shows the cylinder pressure when combustion is not performed, and the dot-chain line shows the cylinder pressure at the time of poor flame propagation.
θ 1 is a predetermined crank angle in the compression stroke just before ignition. The actual cylinder pressure detected at θ 1 is made P 1r . θ 2 is a predetermined crank angle near the crank angle where the cylinder pressure at combustion is the greatest right after the TDC. The cylinder pressure at θ 2 when combustion is not performed is made P 2 and the cylinder pressure detected at θ 2 is made P 2r . θ 3 is a predetermined crank angle in the combustion stroke in the latter period of combustion. The actual cylinder pressure detected at θ 3 is made P 3r .
Referring again to FIG. 11A and FIG. 11B, if the decision at step 90 is negative, the routine proceeds to step 94, where it is determined if the crank angle θ is θ 2 . If the decision is negative, the routine proceeds to step 102, where it is determined if the misfiring flag FQ 2 is set, that is, if early misfiring has occurred. If the decision is negative, the routine proceeds to step 103, where it is determined if the crank angle θ is θ 3 . If the decision is negative, the routine proceeds to step 107, where it is determined if the correction value KQR is smaller than a predetermined lower limit value KQR1.
When the correction value KQR is smaller, the division rate QR becomes smaller (see step 73 in FIG. 8). If the division rate QR is small, the ratio of the amount of fuel injection in the compression stroke becomes larger, so the air-fuel mixture near the spark plug at the time of ignition becomes richer. Therefore, in the case where the correction value KQR is small, such as when KQR<KQR1, it is determined that the air-fuel mixture near the spark plug at the time of ignition is rich and at step 108, the rich flag FLR is set to 1.
On the other hand, when KQR≧KQR1, the routine proceeds to step 109, where it is determined if the correction value KQR is larger than the predetermined upper limit KQR2. Here, KQR2>KQR1. When the correction value KQR is larger, the division rate QR also becomes larger (see step 73 in FIG. 8). If the division rate QR is large, the ratio of the amount of fuel injection at the compression stroke becomes smaller, so the air-fuel mixture near the spark plug at the time of ignition becomes lean. Therefore, in the case where the correction value KQR is large such as when KQR>KQR2, it is determined that the air-fuel mixture near the spark plug at the time of ignition is lean and at step 110 the rich flag FLR is reset to 0.
On the other hand, when KQR≦KQR2, the rich flag FLR is not changed.
In the next and subsequent processing cycles, when it is determined at step 90 that θ=θ 1 , the routine proceeds to step 91, where the actual cylinder pressure P 1r at the crank angle θ 1 is detected. At step 92, P 2 is found from the map (see FIG. 13) based on P 1r . P 2 is increased linearly in accordance with the increase of P 1r . At step 93, P 3 is found from the map (see FIG. 14) based on P 1r and the amount of fuel injection Q. P 3 is the reference cylinder pressure for determining if the cylinder pressure P 3r detected at the crank angle θ 3 is the cylinder pressure when excellent combustion is achieved. After the above processing, the routine is ended.
In the next and subsequent processing cycles, when it is determined at step 94 that θ=θ 2 , the routine proceeds to step 95, where the actual cylinder pressure P 2r at the crank angle θ 2 is detected. At step 96, it is determined if P 2r /P 2 is larger than a judgement value W. When the fuel is excellently ignited and no early misfiring occurs, P 2r becomes sufficiently larger than P 2 , so P 2r /P 2 >W and the routine proceeds to step 97, where the misfiring flag FQ 2 is reset.
On the other hand, when early misfiring occurs, it is judged that P 2r /P 2 ≦W and the routine proceeds to step 98. At step 98, it is determined if the rich flag FLR is set to 1. This rich flag FLR is a measure for determining if the air-fuel mixture near the spark plugs at the time of ignition is rich or not. When the rich flag FLR is set to 1, it is judged that the mixture is rich.
When the decision at step 98 is affirmative, that is, it is determined that rich misfiring has occurred due to the air-fuel mixture near the spark plugs at the time of ignition being rich, the routine proceeds to step 99, where the correction coefficient KQR is increased by X. By this, the division rate QR is increased (see step 73 in FIG. 8) and therefore the ratio of the fuel injection in the compression stroke is reduced and the air-fuel mixture near the spark plugs at the time of ignition can be made leaner. As a result, rich misfirings can be prevented and excellent combustion can be obtained.
On the other hand, when the decision at step 98 is negative, that is, when it is determined that lean misfiring has occurred due to the air-fuel mixture near the spark plugs at the time of ignition being lean, the routine proceeds to step 100, where the correction coefficient KQR is reduced by X. By this, the division rate QR is reduced and therefore the ratio of the amount of fuel injection in the compression stroke is increased and the air-fuel mixture near the spark plugs at the time of ignition can be made richer. As a result, lean misfirings can be prevented and excellent combustion can be obtained.
At step 101, the misfiring flag FQ 2 is set to 1. After this, the routine proceeds to step 107, where the FLR is controlled and then the main routine is ended.
In the next and subsequent processing cycles, the routine proceeds to step 102, where is FQ 2 is set to 1, that is, if it is determined that early misfirings occur, step 103 to step 106 are skipped. That is, step 103 to step 106 are executed only when no early misfirings occur.
If the decision at step 102 is negative, the routine proceeds to step 103, where it is determined if the crank angle θ is θ 3 . When θ becomes θ 3 , the routine proceeds to step 104, where the actual cylinder pressure P 3r (see FIG. 12) at the crank angle θ 3 is detected. At step 105, it is determined if P 3r /P 3 is larger than the judgement value Y. When combustion is excellent and poor flame propagation does not occur, P 3r becomes sufficiently large with respect to P 3 , so P 3r /P 3 >Y and step 106 is skipped.
On the other hand, when poor flame propagation occurs and excellent combustion is not achieved, it is determined that P 3r /P 3 ≦Y and the routine proceeds to step 106, where the correction value KQR is increased by Z. That is, poor flame propagation occurs due to the air-fuel premixture being lean, so by increasing the correction value KQR, the division rate QR is increased and the ratio of the amount of fuel injection in the intake stroke is increased. As a result, the air-fuel premixture can be made leaner and excellent combustion can be obtained.
As explained above, according to the present embodiment, the cylinder pressure is detected, the state of combustion is evaluated based on the cylinder pressure, and the ratio of the amount of fuel injection in the intake stroke and the amount of fuel injection in the compression stroke is changed based on the evaluation, so it is possible to obtain excellent combustion.
Note that while this embodiment showed the use of a single fuel injector to perform the fuel injection in the intake stroke and the fuel injection in the compression stroke, it is possible to add port fuel injectors at the intake ports of the cylinders and use these port fuel injectors to perform the injection at the intake stroke.
Although the present invention has been described with reference to specific embodiments chosen for purposes of illustration, it should be apparent that numerous modifications can be made thereto without departing from the basic concept and scope of the invention.
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A control device for an internal combustion engine having a cylinder and a spark plug, the control device including a fuel feeding unit for feeding fuel into the cylinder, feeding a part of an amount of fuel to be injected during an intake stroke to form an air-fuel premixture, and feeding the remaining part of the amount of fuel to be injected during a compression stroke to form an air-fuel mixture around the spark plug for ignition; a pressure detecting unit for detecting pressure in the cylinder; a combustion state determining unit for determining a combustion state in the cylinder on the basis of the pressure detected by the pressure detecting unit; and a fuel feeding control unit for controlling a ratio of the part of the amount of fuel to be injected to the amount of fuel to be injected on the basis of the result of determination of the combustion state determining unit so that a good state of combustion is obtained.
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BACKGROUND
[0001] Conventional heavy duty trucks have a large engine covering hood which tilts about a transverse pivot point located above the bumper to expose the engine for servicing. Although commonly made of lightweight materials, these hoods are nevertheless cumbersome to handle in part because of their heaviness and the relatively long moment arm between the center of gravity of the hood and the pivot axis. For example, the mass of the hood makes arresting its movement toward either the open or closed position a challenge.
[0002] A hood tilt assist mechanism is often disposed between the hood and a portion of the vehicle to slow the hood when it is moved into either the open or closed position. The hood tilt assist mechanism normally includes a counterbalancing device to control the movement of the hood, thereby assisting the user. The counterbalancing device may be an extension or compression spring, a cable, a shock-absorber, a gas spring, etc.
[0003] In addition to the hood tilt assist mechanism, the vehicle may also include an automatic locking device that secures the hood in the open position to prevent inadvertent closure of the hood and avoid injuring the operator. However, including a locking device separately from the hood tilt assist mechanism increases the number of assemblies within the truck. Moreover, many automatic lock designs include multiple moving parts, which increase assembly time and decreases production. Additionally, use of multiple moving parts within a lock causes the lock components to wear quickly and fail over time.
[0004] Thus, it is desired to provide a hood tilt assist mechanism having a simplified automatic locking system integrated therewithin.
SUMMARY
[0005] A hood support for a vehicle having a hood moveable between open and closed positions is provided. The hood support includes a spring assembly disposable between the vehicle hood and another portion of the vehicle. The spring assembly is moveable into an extended position to accommodate movement of the hood into the open position and moveable into a compressed position to accommodate movement of the hood into the closed position. The hood support further includes a lock tube surrounding a portion of the spring assembly and moveable relative to the spring assembly. The lock tube is selectively actuatable between a locked position, wherein the lock tube secures the spring assembly in the extended position, and an unlocked position, wherein the spring assembly is permitted to be displaced into the compressed position.
[0006] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
DESCRIPTION OF THE DRAWINGS
[0007] The foregoing aspects and many of the attendant advantages of the present disclosure will become more readily appreciated by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
[0008] FIG. 1 is an environmental view of a representative embodiment of a hood support shown in combination with a vehicle hood assembly;
[0009] FIG. 2 is a side planar view of the hood support of FIG. 1 with portions removed for clarity and showing the hood support is shown in a first position;
[0010] FIG. 3 is a side planar view of the hood support of FIG. 2 , showing the hood support in a second position;
[0011] FIG. 4 is a side planar view of the hood support of FIG. 2 , showing the hood support in a third position;
[0012] FIG. 5 is a side planar view of the hood support of FIG. 2 , showing the hood support in a fourth position; and
[0013] FIG. 6 is a side planar view of the hood support of FIG. 2 , showing the hood support in a fifth position and the engine hood assembly in a closed position.
DETAILED DESCRIPTION
[0014] A hood support 10 constructed in accordance with one embodiment of the present disclosure is best seen by referring to FIG. 1 . The hood support 10 is shown in combination with a heavy duty truck T having a cab C, a chassis or frame F, and a hood H. The hood H is pivotally coupled at its forward end to the frame F through a suitable hinge assembly A that is well known in the art. The hood H pivots about the hinge assembly A to move between open and closed positions. The hood support 10 is disposed between the hood H and the frame F and is adapted to control the movement of the hood H when it is moved between the open and closed positions. The hood support 10 also temporarily locks the hood H in the open position.
[0015] Referring now to FIGS. 2 and 3 , the hood support 10 includes a spring assembly, or a spring strut 14 and a locking assembly 16 secured thereto. The spring strut 14 is adapted to slow the hood H as it is moved between the open and closed positions. The spring strut 14 may be any suitable off-the-shelf spring strut with the required spring rate to control the movement of the hood H between the open and closed positions. The spring strut 14 also has a suitable stroke length to position the spring strut 14 between the hood H and the frame F in both the open and closed positions.
[0016] The spring strut 14 includes a cylinder 22 that houses two counterbalanced springs 20 and 21 . The cylinder 22 of the spring strut 14 includes an upper end 78 ( FIG. 1 ) and a lower end 82 having an opening therein for slidably receiving a rod 18 . The rod 18 is slidably disposed within the cylinder 22 and operably coupled to each spring 20 and 21 through a piston 24 or other support member such that the springs 20 and 21 are compressible and extendible by the rod 18 . The rod 18 extends outwardly from the lower end 82 of the cylinder 22 and is received within a portion of the locking assembly 16 . The counterbalanced springs 20 and 21 extend and compress as needed to accommodate the movement of the rod 18 within the cylinder 22 and the overall extension or compression of the spring strut 14 . It should be appreciated that any other suitable spring assembly may instead be used, such as a dual direction gas spring or a compression or extension gas spring.
[0017] The locking assembly 16 includes a lock tube 26 that is adapted to receive the spring strut 14 therewithin. The rod 18 is received within a first tube end 30 of the lock tube 26 and extends downwardly into the lock tube 26 . The rod 18 passes through an opening in a second tube end 34 of the lock tube 26 and is thereafter received within a lower end fitting 70 . The lower end fitting 70 is adapted to pivotally mount the rod 18 to the frame F. The interior of the lock tube 26 is also of a diameter sufficiently large to receive the cylinder 22 therewithin, as shown in FIGS. 4 and 5 . In this manner, when the spring strut 14 compresses a predetermined amount, the cylinder 22 is slidably receivable within the lock tube 26 to allow the spring strut 14 to fully compress and the hood H to close. Although the lock tube 26 is preferably cylindrical in shape, it should be appreciated that any suitable shape may be used, such as rectangular.
[0018] The lock tube 26 is movably secured to the spring strut 14 such that the lock tube 26 may rotate relative to the spring strut 14 when the hood H is moved between open and closed positions. Preferably, the second lock tube end 34 of the lock tube 26 is pivotally coupled to the rod 18 in any suitable manner, such as with a pin assembly 36 that passes through both the lock tube 26 and the rod 18 . The lock tube 26 may instead be pivotally coupled to the frame F in any suitable manner that allows the lock tube 26 to rotate relative to the spring strut 14 .
[0019] Referring to FIG. 2 , the first tube end 30 of the lock tube 26 is angled to define an upper first tube end portion 38 and a lower first tube end portion 42 . Secured to the exterior of the lock tube 26 near the lower first tube end portion 42 of the first tube end 30 is a lock handle 46 . The lock handle 46 includes a tube mating portion 50 secured to the exterior of the lock tube 26 and a handle portion 54 extending upwardly therefrom. The tube mating portion 50 is secured to the exterior of the lock tube 26 in any suitable manner, such as by welding. The handle portion 54 extends upwardly from the lower first tube end portion 42 of the first tube end 30 .
[0020] The handle portion 54 includes a cylinder engaging surface 58 formed on the interior of the handle portion 54 and suitably contoured for engaging the cylinder 22 of the spring strut 14 . A magnet 62 is disposed within the upper end of the handle portion 54 and is substantially flush with the cylinder engaging surface 58 . The magnet 62 secures the cylinder 22 against the cylinder engaging surface 58 when the lock tube 26 is rotated and the lock handle 46 engages the cylinder 22 (See FIG. 4 ). Thus, when the spring strut 14 compresses and the cylinder 22 is moved along the rod 18 , the cylinder 22 slides against the cylinder engaging surface 58 . The cylinder engaging surface 58 provides path that guides the cylinder 22 downwardly towards the lock tube 26 .
[0021] The handle portion 54 further includes a cam surface 66 formed at the bottom interior of the handle portion 54 that extends outwardly from the cylinder engaging surface 58 towards the lock tube 26 . The cam surface 66 is adapted to urge the cylinder 22 into the lock tube 26 as the cylinder 22 slides downwardly against the cylinder engaging surface 58 . Additionally, the cam surface 66 separates the cylinder 22 from the magnet 62 as the cylinder 22 slides downwardly to allow the cylinder 22 to be received within the lock tube 26 .
[0022] Referring back to FIG. 1 , the lower end fitting 70 pivotally secures the rod 18 to the frame F. A similar upper end fitting 74 is secured to the cylinder upper end 78 for pivotally mounting the cylinder 22 to the hood H. The upper and lower end fittings 70 and 74 may be any suitable fitting assembly adapted to pivotally secure the rod 18 to the frame F and the cylinder 22 to the hood H. With the spring strut 14 of the hood support 10 pivotally secured to the frame F and the hood H, the hood support 10 accommodates the movement of the hood H when the hood H is moved between the open and closed positions. It should be appreciated that the hood support 10 may also accommodate the hood movement with the cylinder upper end 78 pivotally secured to the frame F and the rod 18 pivotally secured to the hood H.
[0023] FIGS. 1-6 show the movement and operation of the hood support 10 as the hood H is moved between the open and closed positions. FIG. 6 shows the hood H in a closed position. When the hood H is in the closed position, the spring strut 14 is compressed due to the weight of the hood H, and the cylinder 22 is received within the lock tube 26 .
[0024] Referring to FIG. 1 , the hood H is opened by lifting the rear portion of the hood H and rotating the hood H in a clockwise direction about the hinge assembly A. As the hood H is lifted into the open position, the spring strut 14 extends, and the cylinder 22 moves upwardly out of the lock tube 26 . To aid the operator, the springs 20 and 21 are preferably adapted to urge the hood H at least slightly into the open position while controlling the movement of the hood H. As the hood H is being opened, the spring strut 14 pivots at the lower end fitting 70 and the upper end fitting 74 to accommodate the clockwise rotation of the hood H about the hinge assembly A. The hood H is lifted until the center of gravity of the hood H pivots about the hood assembly A and the cylinder 22 is no longer received within the lock tube 26 , thereby placing the hood H in the open position.
[0025] Referring to FIG. 2 , with the hood H in the open position, the hood support 10 is disposed between the hood H and the frame F at an angle such that the lock tube 26 rotates clockwise about the pin assembly 36 due to the gravitational effects on the lock tube 26 . The lock tube 26 rotates clockwise until the interior of the lock tube 26 engages the rod 18 . As such, the lock tube 26 is positioned against the rod 18 such that the upper first tube end portion 38 is situated substantially beneath the cylinder 22 , or in a locked position. With the lock tube 26 in the locked position, the spring strut 14 cannot compress. More specifically, the upper first tube end portion 38 of the lock tube 26 prevents the cylinder 22 from sliding downwardly along the rod 18 . Accordingly, the hood H is locked in the open position, thereby preventing any accidental closure and avoiding possible injury.
[0026] FIG. 3 depicts the hood H being moved towards the closed position with the lock tube 26 in the locked position. This may occur if, for instance, a strong wind blows against the hood H. The hood H rotates counterclockwise until the cylinder lower end 82 engages the upper first tube end portion 38 , or the spring-engaging portion, of the lock tube 26 . With the lock tube 26 in the locked position, the cylinder 22 cannot slide along the rod 14 to allow the spring strut 14 to compress and the hood H to close. As such, the hood support 10 is maintained in the open position.
[0027] Referring to FIG. 4 , to unlock the hood support 10 and close the hood H, the operator grasps the lock handle 46 and pushes the lock handle 46 and lock tube 26 toward the spring strut 14 until the cylinder engaging surface 58 and the magnet 62 engage the cylinder 22 . The magnet 62 secures the lock handle 46 to the cylinder 22 , thereby preventing the lock tube 26 from rotating clockwise back into the locked position.
[0028] Referring to FIG. 5 , the weight of the hood H as well as any external downward force exerted by the operator causes the spring strut 14 to compress in a controlled manner. As the spring strut 14 compresses, the cylinder 22 travels downwardly against the cylinder engaging surface 58 . The magnet 62 maintains contact between the cylinder engaging surface 58 and the cylinder 22 such that the lock tube 26 is maintained in the unlocked position as the spring strut 14 compresses. The spring strut 14 continues to compress and the cylinder 22 continues to travel downwardly against the cylinder engaging surface 58 until the cylinder engages the cam portion 66 .
[0029] When the cylinder lower end 82 engages the cam portion 66 and travels downwardly along the cam surface 66 , it is urged away from the lock handle 46 and towards the lock tube 26 . The cylinder lower end 82 travels along the cam surface 66 until the cylinder 22 separates from the magnet 62 . As such, the lock handle 46 is no longer secured to the cylinder 22 , and gravity causes the lock tube 26 to rotate clockwise. However, the upper first tube end portion 38 engages the cylinder 22 as the lock tube 26 is rotating clockwise, which prevents the lock tube 26 from moving into the locked position. Thus, the spring strut 14 continues to compress and the cylinder 22 is received within the lock tube 26 . The spring strut 14 compresses until the hood H is closed, as shown in FIG. 6 .
[0030] While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the present disclosure.
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A hood support for a vehicle having a hood moveable between open and closed positions is provided. The hood support includes a spring assembly disposable between the vehicle hood and another portion of the vehicle. The spring assembly is moveable into an extended position to accommodate movement of the hood into the open position and moveable into a compressed position to accommodate movement of the hood into the closed position. The hood support further includes a lock tube surrounding a portion of the spring assembly and moveable relative to the spring assembly. The lock tube is selectively actuatable between a locked position, wherein the lock tube secures the spring assembly in the extended position, and an unlocked position, wherein the spring assembly is permitted to be displaced into the compressed position.
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BACKGROUND OF THE INVENTION
[0001] Windows such as those which are found in residential settings are typically provided with window treatments. The term window treatment is used herein to include curtains, drapes, fabric panels, blinds and valences. Any type of drapery fabric, curtain fabric, wood, metal, jute, bamboo or other natural or man-made material may be used to make the window treatment of the invention.
[0002] The primary function of a window treatment is to restrict the amount of light and visual access through windows but the aesthetic result is considered by most purchasers as being the primary basis for selection of one of a plurality of competing styles. Once a particular style is chosen it is usually not possible to vary the visual effect that a particular style provides when the window treatment is placed in front of a window. Examples of several prior art window treatments are found in U.S. Pat. No. 2,668,587; U.S. Pat. No. 2,611,428; U.S. Pat. No. 6,142,210 and U.S. Pat. No. 3,952,988.
[0003] Generally, window treatments are cut to provide various visual effects in that when the window treatment is placed in position in front of a window, the window is “framed” by the profile of the window treatment. The visual effect of a particular window treatment may only be modified by using cloth tie backs or means which allow for the horizontally movement of the window treatment such as movable suspending means or traverse rods.
[0004] The applicants have devised a window treatment system which has a plurality of fastening means that are arranged to allow for the partial or complete raising of the window treatment. This structure allows the user to select a number of positions which vary the exposure of the window to admit varying amounts of light or visual access to the window opening without having to remove the window treatment from its fixed position in front of a window.
SUMMARY OF THE INVENTION
[0005] The invention provides a window treatment which is sized to fit substantially over a window opening, said window treatment having one or more loop means which are affixed to said window treatment in order to allow a lower portion of said window treatment to be raised vertically and affixed to a surface of said window treatment to expose a portion of the surface of said window opening. Generally there will be one row of button means and from 1 to 7, preferably 3 to 5 rows of loop means. The button means and loop means are intended to hold a lower portion of the window treatment to an upper portion of the window treatment.
[0006] Accordingly, it is a primary object of this invention to provide a window treatment that can be arranged in different configurations when it is hung in front of a window.
[0007] It is also an object of the invention to provide a window treatment that can be arranged in many configurations to provide different visual impressions.
[0008] It is also an object of the invention to provide a window treatment which may be easily opened and closed to act as a privacy closure for a window as well as a decorative window treatment.
[0009] It is also an object of the invention to provide a window treatment that provides at least two distinct visual impressions by means of button means and loop means that may be used to vary the area of the window opening that is exposed on the inside of the window.
[0010] These and other objects of the invention will become apparent from a review of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a front plan view of a fabric panel having tab tops, a horizontal row of button means and the horizontal rows of loop means.
[0012] [0012]FIG. 2 is a front view of the fabric panel of FIG. 1 where the three rows of loops have been fastened seriatim onto the button means.
[0013] [0013]FIG. 3 is a perspective view of FIG. 2 which shows the folded edges of the fabric panel when the rows of loops are attached to the button means.
DETAILED DESCRIPTION OF THE INVENTION
[0014] [0014]FIG. 1 discloses an embodiment of a fabric panel 2 having tab tops 3 , 3 a , 3 b , 3 c , 3 d and 3 e having interacting means which comprise button row 4 and loop rows 6 , 6 a and 6 b . The buttons 5 , 5 a , 5 b , 5 c , 5 d and 5 e are spaced at substantially equal intervals in a horizontal direction across the fabric panel 2 .
[0015] The loop rows 6 , 6 a and 6 b are spaced at gradually increasing intervals from the bottom of the fabric panel to the top of the fabric panel in order to provide substantially equal amounts of exposed fabric 10 , 12 on the hidden panels 14 , 16 which are under folded sections 18 and 20 when the rows of loops 6 , 6 a and 6 b are all fastened to the button means 5 , 5 a , 5 c , 5 d and 5 e . Front sections 18 , 20 and 22 result from the folding of the fabric panel to allow for fastening of the loops onto the button means.
[0016] As best seen in FIG. 2, when all of the loops in rows 6 , 6 a and 6 b are fastened sequentially with the highest row being fastened first and the lowest row being fastened last to the button means the fabric panel presents a series of folded edges 10 , 12 which provide an aesthetically pleasing front and side profiles to the viewer. At the same time, the buttons and loops function to provide a secure means of holding the fabric panel in one or more open positions that may be used for control of the amount of light that is allowed to pass through the window.
[0017] If desired, the fabrics may be printed in such a manner that a preselected design may be formed when the window treatment is placed in the “button up” position.
[0018] The embodiment of FIG. 1 is shown with a tab top suspending means but any other type of ring or rod type suspending sleeve may be used to provide a means for suspending the window treatments of the invention.
[0019] The button means may comprise any type of a protrusion such as a post, button, knob, curved hook, Velcro etc. that is capable of holding a fabric or rope type loop means such as, or a loop of roping or thread, a metal ring, snaps, button holes or Velcro type of fastening system. The button means and the loop means are sized to allow for quick engagement and disengagement of the button means in order to facilitate the operation of the window treatment. While it is preferred to place the button means and loop means as shown in FIG. 1, it is possible to reverse the positions of the button means and the loop means so that rows of button means are available to be affixed to a single row of loop means located at the upper part of the window treatment.
[0020] The rows of button means and loop means may be spaced as shown in FIG. 3 or in any type of spacing to achieve any desired effect. The rows of button means and loop means are shown in a horizontal arrangement but it is within the scope of the invention to arrange the rows of button means and loop means in various angled or arced configurations to achieve any desired visual effect. Each row of button means and loop means may comprise from 3 to 10, preferably 4 to 8 button means and loop means, depending on the weight of the fabric, the width of the panel and the visual effect that is desired.
[0021] It is preferred to use one row of buttons arranged horizontally at a location which is within 0-12 inches, preferably within four inches of the top edge of the means which are used to suspend the panel in front of the window.
[0022] The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. All such obvious modifications and variations are intended to be within the scope of the appended claims.
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A window treatment which is sized to fit over a window opening and has one or more rows of loop means which are affixed to said window treatment which allow a lower portion of said window treatment to be raised vertically and affixed to a surface of said window treatment to expose a portion of the surface of said window opening.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] Referring to the application data sheet filed herewith, this application is a continuation of, and claims a benefit of priority under 35 U.S.C. 120 from copending utility or design patent application U.S. Ser. No. 12/658,582, filed Feb. 9, 2010 (now U.S. Pat. No. 9,095,684 issued Aug. 4, 2015) the entire contents of which are hereby expressly incorporated herein by reference for all purposes.
BACKGROUND INFORMATION
[0002] 1. Field of the Invention
[0003] Embodiments of the invention relate generally to the field of cardio/vascular intervention, especially angiograpy. More particularly, an embodiment of the invention relates to a bidirectional introducer catheter with an antegrade/retrograde access sheath to allow both catheter directions through a single arteriotomy. In more detail, the bidirectional introducer catheter is enabled by an antegrae/retrograde access sheath that includes dilator that includes a distal end with softer section and one or more reinforced arch(es).
[0004] 2. Discussion of the Related Art
[0005] Referring to FIGS. 1-2 , retrograde access limits access to distal vascular beds due to length of trajectory; and increased catheter friction due to the sharp angulation of the aorto Iliac bifrication. Also, retrograde access limits possible imaging of the ipsilateral limb. Reversal of access direction is very difficult or impossible with current technique.
[0006] Referring to FIGS. 1-3 , antegrade access has these same limitations and, in addition, is technically more difficult due to anatomical considerations, especially in obese patients. Many interventionalists are daunted by this due to lack of training.
[0007] What are needed are more effective and efficient devices for access. What are also needed are devices for reversible or bidirectional introduction of catheters.
SUMMARY OF THE INVENTION
[0008] There is a need for the following embodiments of the invention. Of course, the invention is not limited to these embodiments.
[0009] According to an embodiment of the invention, a bidirectional introducer comprises a catheter including: a sheath; and a dilator located within and substantially coaxially with the sheath, the dilator having a distal end portion that includes at first section having a proximal first section end and a distal first section end, a second softer section having a proximal second section end and a distal second section end and a third reinforced section having a proximal third section end and a distal third section end, wherein a) the distal first section end is coupled to the proximal second section end and the distal second section end is coupled to the proximal third section end and b) i) at least a portion of the first section is characterized by a first rigidity and at least a portion of the second softer section is characterized by a second rigidity that is lower than the first rigidity and ii) at least a portion of the third reinforced section is characterized by a third rigidity that is higher than both the first rigidity and the second rigidity, wherein the distal end portion includes a fourth section having a proximal fourth section end and a distal fourth section end, wherein a) the distal third section end is coupled to the proximal fourth section end and b) at least a portion of the fourth section is characterized by a fourth rigidity that is lower than the third rigidity and higher than the second rigidity, and further comprising a guide wire located within and substantially coaxially with the dilator, wherein the guide wire can be moved relative to the dilator to increase a radius of curvature characterized by the distal end portion, wherein the distal end portion includes a fifth softer section having a proximal fifth section end and a distal fifth section end, wherein a) the distal fourth section end is coupled to the proximal fifth section end and b) at least a portion of the fifth softer section is characterized by a fifth rigidity that is lower than the first rigidity.
[0010] According to another embodiment of the invention, a method of using a bidirectional introducer catheter comprises inserting a sheath, dilator and guide wire into a mammal; partially withdrawing the guide wire with regard to the dilator to reversibly deform the dilator; partially withdrawing the dilator to reposition the dilator with regard to the sheath; at least partially withdrawing the sheath; rotationally swinging the sheath into a reversed position; reinserting the guide wire to reform the dilator; and reinserting the sheath.
[0011] These, and other, embodiments of the invention will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following description, while indicating various embodiments of the invention and numerous specific details thereof, is given for the purpose of illustration and does not imply limitation. Many substitutions, modifications, additions and/or rearrangements may be made within the scope of an embodiment of the invention without departing from the spirit thereof, and embodiments of the invention include all such substitutions, modifications, additions and/or rearrangements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The drawings accompanying and forming part of this specification are included to depict certain embodiments of the invention. A clearer concept of embodiments of the invention, and of components combinable with embodiments of the invention, and operation of systems provided with embodiments of the invention, will be readily apparent by referring to the exemplary, and therefore nonlimiting, embodiments illustrated in the drawings (wherein identical reference numerals (if they occur in more than one view) designate the same elements). Embodiments of the invention may be better understood by reference to one or more of these drawings in combination with the following description presented herein. It should be noted that the features illustrated in the drawings are not necessarily drawn to scale.
[0013] FIG. 1 is a view of two catheter sheaths, one positioned for retrograde access and the other positioned for antegrade access.
[0014] FIG. 2 is a larger scale view of two catheter sheaths, again one positioned for retrograde access and the other positioned for antegrade access.
[0015] FIG. 3 is a view of a catheter sheath positioned for antegrade access and a dilator ready to be introduced into the sheath.
[0016] FIGS. 4-7 are four set views of four bidirectional introducer dilators (each member of each of set shown axially rotated 90 degrees to illustrate the three dimensional compound curve shape of each of the four dilators.
[0017] FIGS. 8-10 are three views of a bidirectional introducer dilator with a guide wire located in the dilator positioned at three stages of withdrawal.
[0018] FIG. 11 is a view of a bidirectional introducer positioned for antegrade access showing the sheath, dilator and guide wire.
[0019] FIG. 12 is a view of the bidirectional introducer about to begin being repositioned for retrograde access showing the sheath, dilator and guide wire now partially withdrawn with regard to the sheath and dilator.
[0020] FIG. 13 is a view of the bidirectional introducer being repositioned for retrograde access showing the sheath, dilator now partially withdrawn with regard to the sheath, and, guide wire again partially withdrawn.
[0021] FIG. 14 is a view of the bidirectional introducer being repositioned for retrograde access showing the sheath now partially withdrawn, dilator again partially withdrawn, and, guide wire now re-extended.
[0022] FIG. 15 is a view of the bidirectional introducer being repositioned for retrograde access showing the sheath now being swung toward reversed position, dilator again partially withdrawn, and, guide wire re-extended.
[0023] FIG. 16 is a view of the bidirectional introducer being repositioned for retrograde access showing the sheath further swung toward reversed position, dilator now being reinserted, and, guide wire re-extended.
[0024] FIG. 17 is a view of the bidirectional introducer being further repositioned for retrograde access showing the sheath now being reinserted, dilator still partially reinserted, and, guide wire re-extended.
[0025] FIG. 18 is a view of the sheath with dilator and guide wire fully withdrawn.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] Embodiments of the invention and the various features and advantageous details thereof are explained more fully with reference to the nonlimiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well known starting materials, processing techniques, components and equipment are omitted so as not to unnecessarily obscure the embodiments of the invention in detail. It should be understood, however, that the detailed description and the specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only and not by way of limitation. Various substitutions, modifications, additions and/or rearrangements within the spirit and/or scope of the underlying inventive concept will become apparent to those skilled in the art from this disclosure.
[0027] The ability to reverse catheter direction during intervention will optimize angiograpy. Also, the ability to reverse catheter direction during intervention would make multi-vessel intervention feasible, which would result in very significant equipment savings and patient convenience.
[0028] Referring to FIGS. 4-7 , an appropriately shaped “shepherds crook” sheath dilator with reinforcement in its arch, and appropriately sized to navigate through Iliac arteries, will allow for reversal of direction in a large percentage of patients, with minimal additional training for the interventionalist and at very little additional cost. It is important to appreciate that FIGS. 4-7 are four set views of four different bidirectional introducer dilators 400 , 500 , 600 , 700 (each member of each of set shown axially rotated 90 degrees to illustrate the three dimensional compound curve shape of each of the four dilators). In more detail, and still referring to FIGS. 4-7 , The lightly shaded areas are softer, for instance, rubberized or siliconized. The darker shaded areas are reinforced for shape retention and support.
[0029] Shape and size(s) of the tip(s) may need to be tested prior to arriving at a preferred shape for a generic, subgeneric and/or specific intervention and/or patient. While not being limited to any particular performance indicator, preferred embodiments of the invention can be identified one at a time by testing that the catheter preferably will straighten on a standard 0.035″ guidewire. Among the other ways in which to seek guidance toward the next preferred embodiment, this can be based on the presence of initial shape retention preferably sufficient to allow for traversing the Iliac arteries in its conformation and in an atraumatic manner. Among the other ways in which to seek guidance toward the next preferred embodiment, this can be based on the presence of enough torque control preferably being present to allow for some directional maneuvers when in the common femoral artery to be able to sub-select the superficial femoral artery.
[0030] An embodiment of the invention can also be included in a kit-of-parts. The kit-of-parts can include some, or all, of the components that an embodiment of the invention includes. The kit-of-parts can be an in-the-field retrofit kit-of-parts to improve existing systems that are capable of incorporating an embodiment of the invention. The kit-of-parts can include software, firmware and/or hardware for carrying out an embodiment of the invention. The kit-of-parts can also contain instructions for practicing an embodiment of the invention. Unless otherwise specified, the components and/or instructions of the kit-of-parts can be the same as those used in an embodiment of the invention.
[0031] The particular manufacturing process used for fabrication of the bidirectional introducer catheter dilator should be inexpensive and reproducible. Conveniently, the fabrication of an embodiment of the invention can be carried out by using any joining method for coupling the sections of differing rigidity. It is preferred that the process be capable of producing a finished article of manufacture having resilient and predicable rigidity and also importantly elastic properties. For the manufacturing operation, it is an advantage to employ a glue based end-to-end joining technique.
[0032] However, the particular manufacturing process used for fabricating the bidirectional introducer catheter dilator is not essential to an embodiment of the invention as long as it provides the described functionality. Normally those who make or use an embodiment of the invention will select the manufacturing process based upon tooling and energy requirements, the expected application requirements of the final product, and the demands of the overall manufacturing process. For instance, the different sections could be coupled with snap-fit technology, infrared welding, injection molding of segregated charge batch or any other suitable joining technique.
[0033] The particular material used for the bidirectional introducer catheter dilator should be non-toxic and biocompatible. Conveniently, the dilator of an embodiment the invention can be made of any multipolymer material. It is preferred that the material be capable of providing a multi-interventional service life. For the manufacturing operation, it is an advantage to employ a copolymer material.
[0034] However, the particular material selected for the bidirectional introducer catheter dilator is not essential to an embodiment of the invention, as long as it provides the described function. Normally, those who make or use an embodiment of the invention will select the best commercially available material based upon the economics of cost and availability, the expected application requirements of the final product, and the demands of the overall manufacturing process. For instance, the material might be a thermoplastic copolymer that is extrusion processed with a variable size die to produce sections of variable outer diameter or variable fluting geometry, thereby yielding a finished dilator with sections of differing rigidity, even though they be composed of the same material.
[0035] The disclosed embodiments show a multi-section (compound) arcuate (that might be compared to a shepard's crook as the structure for performing the function of reversal, but the structure for performing reversal deformation can be any other structure capable of performing the function of reversal, including, by way of example a spiral shape, a screw shape, a quadrahedral shape or other three dimensional polygon.
EXAMPLES
[0036] Specific embodiments of the invention will now be further described by the following, nonlimiting examples which will serve to illustrate in some detail various features. The following examples are included to facilitate an understanding of ways in which an embodiment of the invention may be practiced. It should be appreciated that the examples which follow represent embodiments discovered to function well in the practice of the invention, and thus can be considered to constitute preferred mode(s) for the practice of the embodiments of the invention. However, it should be appreciated that many changes can be made in the exemplary embodiments which are disclosed while still obtaining like or similar result without departing from the spirit and scope of an embodiment of the invention. Accordingly, the examples should not be construed as limiting the scope of the invention.
Example 1
[0037] Referring to FIGS. 8-10 , a single bidirectional introducer catheter 800 is shown. FIG. 8 shows the guide wire fully inserted into the dilator 820 . FIG. 9 shows the guide wire 810 partially inserted into the dilator 820 . FIG. 10 shows the guide wire 810 largely retracted into the dilator 820 . Of course, the invention is not limited to the particular components or positions depicted in FIGS. 8-10 .
Example 2
[0038] Referring to FIGS. 11-18 , a method of interventional reversal is shown. FIG. 11 shows dilator 1110 inserted over 0.035″ guide wire 1120 . In this particular example, the guide wire 1120 includes a soft hydrophilic tip and gradual stiffening such as a Terumo Glide wire. FIG. 12 shows the guide wire 1120 retracted into the bidirectional introducer assembly, this allows the dilator 1110 to recover an original shape. The introducer is pulled until only a curved portion emerges from sheath. The dashed line shows the direction of pull. The guide wire 1120 is mostly retracted. Referring to FIG. 13 , arterial walls “trap” and preserve the original shape of the introducer tip. The sheath is withdrawn until a shaped tip of introducer is at arteriotomy level.
[0039] Referring to FIG. 14 , rotating the introducer as needed, the guide wire can be advanced into the superficial femoral artery. Referring to FIG. 15 , the tip of the introducer is selectively pulled into the superficial femoral artery, rotating it as needed and the guide wire is advanced until the core is firmly in the artery. Referring to FIG. 16 , the dilator is straightened and advanced. Referring to FIG. 17 , the sheath is advanced over the straightened dilator. Referring to FIG. 18 , the dilator and guide wire can be removed. This process can be inverted.
Definitions
[0040] The term substantially is intended to mean largely but not necessarily wholly that which is specified. The term approximately is intended to mean at least close to a given value (e.g., within 10% of). The term generally is intended to mean at least approaching a given state. The term coupled is intended to mean connected, although not necessarily directly, and not necessarily mechanically. The term proximate, as used herein, is intended to mean close, near adjacent and/or coincident; and includes spatial situations where specified functions and/or results (if any) can be carried out and/or achieved. The term distal, as used herein, is intended to mean far, away, spaced apart from and/or non-coincident, and includes spatial situation where specified functions and/or results (if any) can be carried out and/or achieved. The term deploying is intended to mean moving, activating, installing and/or operating.
[0041] The terms first or one, and the phrases at least a first or at least one, are intended to mean the singular or the plural unless it is clear from the intrinsic text of this document that it is meant otherwise. The terms second or another, and the phrases at least a second or at least another, are intended to mean the singular or the plural unless it is clear from the intrinsic text of this document that it is meant otherwise. Unless expressly stated to the contrary in the intrinsic text of this document, the term or is intended to mean an inclusive or and not an exclusive or. Specifically, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present). The terms a and/or an are employed for grammatical style and merely for convenience.
[0042] The term plurality is intended to mean two or more than two. The term any is intended to mean all applicable members of a set or at least a subset of all applicable members of the set. The phrase any range derivable therein is intended to mean any range within such corresponding numbers. The term means, when followed by the term “for” is intended to mean hardware, firmware and/or software for achieving a result. The term step, when followed by the term “for” is intended to mean a (sub)method, (sub)process and/or (sub)routine for achieving the recited result.
[0043] The terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. The terms “consisting” (consists, consisted) and/or “composing” (composes, composed) are intended to mean closed language that does not leave the recited method, apparatus or composition to the inclusion of procedures, structure(s) and/or ingredient(s) other than those recited except for ancillaries, adjuncts and/or impurities ordinarily associated therewith. The recital of the term “essentially” along with the term “consisting” (consists, consisted) and/or “composing” (composes, composed), is intended to mean modified close language that leaves the recited method, apparatus and/or composition open only for the inclusion of unspecified procedure(s), structure(s) and/or ingredient(s) which do not materially affect the basic novel characteristics of the recited method, apparatus and/or composition.
[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.
CONCLUSION
[0045] The described embodiments and examples are illustrative only and not intended to be limiting. Although embodiments of the invention can be implemented separately, embodiments of the invention may be integrated into the system(s) with which they are associated. All the embodiments of the invention disclosed herein can be made and used without undue experimentation in light of the disclosure. Although the best mode of the invention contemplated by the inventor(s) is disclosed, embodiments of the invention are not limited thereto. Embodiments of the invention are not limited by theoretical statements (if any) recited herein. The individual steps of embodiments of the invention need not be performed in the disclosed manner, or combined in the disclosed sequences, but may be performed in any and all manner and/or combined in any and all sequences. The individual components of embodiments of the invention need not be formed in the disclosed shapes, or combined in the disclosed configurations, but could be provided in any and all shapes, and/or combined in any and all configurations. The individual components need not be fabricated from the disclosed materials, but could be fabricated from any and all suitable materials. Homologous replacements may be substituted for the substances described herein. Agents which are both chemically and physiologically related may be substituted for the agents described herein where the same or similar results would be achieved.
[0046] Various substitutions, modifications, additions and/or rearrangements of the features of embodiments of the invention may be made without deviating from the spirit and/or scope of the underlying inventive concept. All the disclosed elements and features of each disclosed embodiment can be combined with, or substituted for, the disclosed elements and features of every other disclosed embodiment except where such elements or features are mutually exclusive. The spirit and/or scope of the underlying inventive concept as defined by the appended claims and their equivalents cover all such substitutions, modifications, additions and/or rearrangements.
[0047] The appended claims are not to be interpreted as including means-plus-function limitations, unless such a limitation is explicitly recited in a given claim using the phrase(s) “means for” and/or “step for.” Subgeneric embodiments of the invention are delineated by the appended independent claims and their equivalents. Specific embodiments of the invention are differentiated by the appended dependent claims and their equivalents.
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A bidirectional introducer includes a dilator having a distal end portion that includes a first section having a distal first section end, a second softer section having a proximal second section end and a distal second section end and a third reinforced section having a proximal third section end, wherein a) the distal first section end is coupled to the proximal second section end and the distal second section end is coupled to the proximal third section end and b) i) at least a portion of the first section is characterized by a first rigidity and at least a portion of the second softer section is characterized by a second rigidity that is lower than the first rigidity and ii) at least a portion of the third reinforced section is characterized by a third rigidity that is higher than both the first rigidity and the second rigidity.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of application Ser. No. 09/033,781 filed Mar. 3, 1998.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a hydro-dynamic fluid bearing device, more detailedly, to a hydro-dynamic fluid bearing device of a spindle motor for an information system, an audio/visual system or the like, especially, to a hydro-dynamic fluid bearing device of a spindle motor suitable for an optical disk system or a magnetic disk system, and also to a method of making a bearing member used in such a device.
2. Related Background Art
Sliding bearings, ball bearings or hydro-dynamic fluid bearings are conventionally used in information systems such as LBPs (laser beam printers) and CD-ROM drive systems. Bearing devices in DVD (digital video disk) systems, which are new information systems, are planned to employ such bearings and some of them are practically utilized.
Bearing devices for laser beam printers, CD-ROM drive systems or the like, require high rigidity, low friction and good durability.
However, conventional bearing devices have the following problems.
In a bearing device using a sliding bearing, a thrust bearing is required in addition to a radial bearing. The number of parts thus increases. Besides, shaft run-out is large. Such shaft run-out is apt to occur in accordance with the size of the gap between a radial bearing and a shaft. Furthermore, wear resistance is bad. Abrasion is apt to be heavy in particular when the rotational speed is high.
In a bearing device using a ball bearing, the ball bearing itself is expensive. Furthermore, rotation unevenness and vibration are apt to occur.
In a bearing device using a hydro-dynamic fluid bearing (made of metal), a thrust bearing is required in addition to a radial bearing. The number of parts thus increases. Besides, wear resistance is low because abrasion is easy to occur due to contact at the time of start or stop. Furthermore, the manufacturing cost is high because of the formation of grooves for generating hydro-dynamic fluid and the highly accurate finish of a bearing surface.
Considering the above problems, the present inventor et al. proposed a hydro-dynamic fluid bearing using a bearing member made of resin which is superior in anti-friction and wear resistance, and can be formed in one body by injection molding, and the cost of which is low. Such a bearing device, however, has the following new problem. Since the rigidity of resin is lower than that of metal, the bearing member made of resin is displaced (elastically deformed) when unbalance quantity (radial load) is large.
In recent years, the rotational speeds of fluid bearing devices for spindle motors of optical disk systems or magnetic disk systems are tend to increase because of the demand of the high speed transmission of data. In a supporting bearing of such a spindle motor, the influence of centrifugal force at a high speed rotation due to the unbalance of a rotation member becomes larger.
FIG. 12 shows a cross-sectional view of a prior art bearing device. A rotation member comprises a shaft 130, a disk attachment flange 131 and a rotor 133. The shaft 130 is rigidly inserted in the disk attachment flange 131. The rotor 133 is fixed to the lower surface of the disk attachment flange 131.
A support member for supporting the shaft 130 comprises a stator 134, a base 135, a bearing member 136 and a steel ball 137. For operating as a radial hydro-dynamic fluid bearing, grooves for generating hydro-dynamic fluid are formed in a cylindrical radial bearing surface 136a of the bearing member 136. The bearing member 136 is firmly inserted in the base 135. The steel ball 137 is tightly inserted in the lower end portion of the bearing member 136. The steel ball 137 operates as a thrust bearing. The stator 134 is firmly inserted in and fixed to the bearing member 136.
The operation will be described. When the stator 134 is electrified, a rotating magnetic field is generated. The rotor 133 thereby rotates together with the shaft 130 and the disk attachment flange 131. The pressure of a lubricant in a radial bearing gap thereby increases because of a pumping effect by the grooves for generating hydro-dynamic fluid formed in the radial bearing surface 136a. The rotor 133 thus rotates in non-contact state between the radial bearing surface 136a and a radial receiving surface 136b which were initially in contact with each other.
In the thrust bearing, a sliding bearing is formed by point contact between a thrust bearing surface 130a of an end surface of the shaft 130 and a thrust receiving surface 137a. The lubricant is disposed between the thrust bearing surface 130a and the thrust receiving surface 137a. The rotor 133 thus rotates in point contact state through the lubricant.
Synthetic oils having good boundary lubrication properties were studied for such a lubricant. Particularly, load capacities of the above radial and thrust bearings are in proportion to the viscosity of a lubricant used. Since the change of the viscosity of synthetic oil with the change of temperature are large, an oil which meets the necessary load capacity at a high temperature, largely increases in its viscosity at a low temperature so as to increase the dynamic torque of a bearing. Contrarily, if an oil having the viscosity where the optimum dynamic torque of a bearing is obtained at a low temperature, is chosen, the viscosity decreases at a high temperature so that the load capacity becomes insufficient. Because synthetic oils are inferior in their temperature-viscosity properties in general, the diameter of the shaft was 1.5 mm for lowering the torque of the bearing device, or the radial bearing gap between the radial bearing surface 136a and the radial receiving surface 136b was narrowed to 3 μm for insuring the necessary load capacity.
When the rotational speed of a bearing device becomes higher, however, the centrifugal force becomes larger due to the unbalance at the time of mounting a disk. The flexural rigidity of the shaft thus lacks, causing a problem that the run-out range of a rotational body becomes larger. Besides, in bearing devices, it is required to lower the torque at a low temperature because of a demand for saving the electric power to the device.
As another prior art, a dynamic air pressure bearing having a construction schematically shown in FIG. 13 is used in a scanner motor for polygon mirror in a laser printer which is an information system. A shaft 202, in the outer surface of which grooves 203 for generating hydro-dynamic fluid are formed, is inserted in a sleeve 201 which is a cylindrical member. A radial dynamic air pressure bearing for supporting the sleeve 201 in the radial direction to the shaft 202 is formed by utilizing an air pressure which is generated by the grooves 203 for generating hydro-dynamic fluid at the relative rotation of the sleeve 201 and the shaft 202. An end opposite to an end through which the shaft 202 is inserted, is closed with a thrust plate 204. A pair of permanent magnets 205 and 206 is mounted on the end surface of the shaft 202 and the inner surface of the thrust plate 204 opposite to the former, respectively, so as to repel each other. A thrust magnetic bearing for supporting the sleeve 201 in the axial direction to the shaft 202 is formed by the repulsion between the permanent magnets 205 and 206.
In the dynamic air pressure bearing as shown in FIG. 13, however, because of the construction where air of low viscosity and little lubrication is used as a lubricant fluid, it is required to finish in very high accuracy the bearing surfaces such as the inner surface of the sleeve 201 and the outer surface of the shaft 202. Besides, the good slidability of those bearing surfaces must be insured. For these purposes, after the inner surface of the sleeve 201 made of structural steel is ground or honed, the inner surface is coated with a composite plating in which polyethylene fluoride resin such as Teflon (trade name), that is, polytetrafluoroethylene is impregnated in nickel. The inner surface is again ground or honed to insure the dimensional accuracy. On the other hand, the grooves for generating hydro-dynamic fluid must be formed by etching in the outer surface of the shaft 202 made of stainless steel which cooperates with the sleeve 201.
As for the sleeve 201, because a thick plating can not be formed, two times of grinding or honing are required. There are problems that the manufacturing cost increases in addition to increasing the cost for plating. As for the shaft 202, there are problems that the process of etching is complex and has need of a long time and the cost increases. Since the magnetic bearing using the repulsion between the permanent magnets 205 and 206 is employed for the thrust bearing, there are problems that the construction is complex, the number of parts increases and the cost for manufacturing the whole of the bearing is high.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a hydro-dynamic fluid bearing device of high rigidity, low friction and good durability by reinforcing a bearing member made of resin with an annular member having higher rigidity than the bearing member made of resin.
It is another object of the present invention to provide a motor including a hydro-dynamic fluid bearing device of the decreased number of parts and low cost by using an annular member as a rotor or a stator of the motor.
For solving the above-described problems, in a hydro-dynamic fluid bearing device according to the first aspect of the present invention, a bearing member made of resin has a cylindrical radial bearing surface in a cylindrical hole, the radial bearing surface has grooves for generating hydro-dynamic fluid, and the bearing member is reinforced by the manner that the outer surface of the bearing member is fixed to an annular member which has the higher rigidity than the bearing member.
The outer surface of the bearing member may be reinforced by the manner that its both end portions in the axial direction are mounted to the annular member. The annular member may be a rotor included in the drive structure of the motor. The annular member may be a stator included in the drive structure of the motor.
Since the bearing member is reinforced by the annular member having the higher rigidity than the bearing member, a lack of the rigidity of the bearing member made of resin is complemented so that the bearing member made of resin is not displaced even in the case of the large unbalance quantity.
A motor of simple structure, the small number of parts and low cost can be obtained if the annular member is utilized as a rotor or a stator of the motor.
It is an object of a hydro-dynamic fluid bearing device according to the second aspect of the present invention to provide a hydro-dynamic fluid bearing device wherein the flexural rigidity of a shaft is to be improved and the problem that the run-out range of a rotational body becomes larger is solved, and the dynamic torque is to be decreased at a low temperature, by aiming at the shape of the bearing device and a lubricant.
A hydro-dynamic fluid bearing device is to provide a hydro-dynamic fluid bearing device in which a cylindrical radial bearing surface of a bearing member is opposite through a radial bearing gap to a radial receiving surface of a shaft, and grooves for generating hydro-dynamic fluid are formed in at least one of the radial receiving surface and the radial bearing surface, characterized in that the diameter of the shaft is 2 to 5 mm, a fluoric oil the kinematic viscosity of which is 20 to 200 cSt at 40° C. is used as a lubricant in the radial bearing gap, and the radial bearing gap is 3.5 to 10 μm.
Since the diameter of the shaft is 2 to 5 mm, the flexural rigidity of the shaft is improved. Within this range, it is possible to decrease the run-out range of a rotation member which is a rotational body. If the diameter of the shaft is larger than 5 mm, the dynamic torque becomes too large.
As a lubricant, a fluoric oil where the increase of torque at a low temperature is small is used. Particularly, when a fluoric oil which has good temperature-viscosity properties and the kinematic viscosity of which is 20 to 200 cSt at 40° C., is used, and the radial bearing gap between the radial bearing surface and the radial receiving surface is 3.5 to 10 μm, the appropriate dynamic torque is obtained at a low temperature.
By this feature, it becomes possible to meet a demand of saving the energy of a bearing device. At a low temperature, since the energy for operating a bearing device had to be increased due to an increase of the viscosity of a lubricant with a difference from the viscosity properties of the lubricant at a normal temperature, there was a requirement of the energy which is not required at the normal temperature. In the present invention, it becomes possible to drive a bearing device without using such extra energy.
As for properties of a fluoric oil as a lubricant, when the kinematic viscosity is less than 20 cSt at 40° C., the dynamic torque becomes small but the load capacity becomes insufficient at a high temperature. When the kinematic viscosity is more than 200 cSt at 40° C., the load capacity becomes large but the dynamic torque becomes too large at a low temperature. For exhibiting fully the effect of the present invention, therefore, the use within the range of 20 to 200 cSt at 40° C. is preferable as described above.
When a fluoric oil as a lubricant includes perfluoropolyether having carboxylic acid at its termination which is mixed by 0.1 to 10 wt. %, boundary lubrication properties and leakage properties of the lubricant are further improved.
But, when a fluoric oil includes perfluoropolyether having carboxylic acid at its termination of less than 0.1 wt. %, the boundary lubrication properties and the leakage properties of the lubricant become inferior. When a fluoric oil includes perfluoropolyether having carboxylic acid at its termination of more than 10 wt. %, physical properties of the fluoric oil become inferior and it becomes difficult to obtain the adequate dynamic torque at a low temperature.
When the radial bearing gap between the radial bearing surface and the radial receiving surface is less than 3.5 μm, the dynamic torque becomes large at a low temperature. When the radial bearing gap is more than 10 μm, the dynamic torque becomes small but the load capacity becomes insufficient at a high temperature. For exhibiting fully the effect of the present invention, therefore, the radial bearing gap within the range of 3.5 to 10 m is preferable as described above.
When the radial bearing gap is within the range of 3.5 to 10 μm, there is an effect that the insertion of the shaft to the bearing member becomes easy even in the state of injecting a lubricant into the bearing member and without forming a vent hole in the bearing member.
A cylindrical radial bearing surface disposed in the bearing member is opposite through a radial bearing gap to a radial receiving surface disposed in a shaft. Furthermore, a thrust receiving surface disposed in an end surface of the shaft may be opposite to a thrust bearing surface disposed in the bearing member.
Grooves for generating hydro-dynamic fluid may be formed in at least one of the radial bearing surface and the radial receiving surface of the hydro-dynamic fluid bearing device. The formation of the grooves is not limited to either the radial bearing surface or the radial receiving surface.
When the structure of point contact between a thrust receiving surface and a thrust bearing surface is employed, the contact area can be considerably decreased so it can be attempted to decrease the dynamic torque. When the thrust receiving surface and the thrust bearing surface are opposite to each other through a lubricant, it is expected to improve boundary lubrication properties and it becomes possible to decrease the abrasion between the contact surfaces. Particularly, when a convex spherical surface is formed in the thrust bearing surface, the process that a steel ball constituting a thrust bearing is tightly inserted to a bearing member can be omitted. It is thus attempted to improve the workability of assembling.
A bearing member having a radial bearing surface and a thrust bearing surface may be integrally formed of synthetic resin. Otherwise, differently from the integral formation, a bearing member having a radial receiving surface may be made of copper group metal such as free-cutting brass and phosphorus bronze, and a thrust receiving member having a thrust bearing surface may be formed of a plate made of wear resisting metal or ceramics. The thrust receiving member is mounted to the bearing member. By employing this structure, it is possible to maintain the strength of the flexural rigidity of the bearing device, and to restrain the phenomenon of generating the abrasion of the thrust receiving member.
As the above, for obtaining the high rigidity, the little abrasion and the good durability at the high speed operation in a hydro-dynamic fluid bearing device, in the first aspect, there was described means for restraining shaft run-out or the like by a combination of a reinforcing member to a bearing member mainly made of resin material. In the second aspect, there was described means for restraining shaft run-out or the like by a combination of the shape and a lubricant to a bearing member made of resin material or others.
These aspects were separately described for simplifying the description since they are effective when separately used. The combination of them, however, bring on the more remarkable effect.
Next, as for a bearing member particularly made of resin material and used in the above first and second aspects, a hydro-dynamic fluid bearing member effective to the above aspects will be described as the third aspect. Like the above first and second aspects, the third aspect will be separately described for simplifying the description. It is needless to say that even only the third aspect is effective to the objects of the present invention.
A hydro-dynamic fluid bearing device according to the third aspect of the present invention is made by paying attention to various problems of conventional bearing devices and its object is to provide a hydro-dynamic fluid bearing of good durability, simple process, the small number of parts and low cost.
For attaining the above object, the present invention is a hydro-dynamic fluid bearing characterized in that a cylindrical portion having grooves for generating hydro-dynamic fluid in its inner surface, and a bottom portion integrally with the cylindrical portion are formed into one body by injection molding with resin material, the nearly central portion of the outer surface of the bottom portion is the portion that the resin material lastly flowed in, the inside diameter of the cylindrical portion is 2 to 5 mm, the thickness of the cylindrical portion is 0.8 to 2 mm, and at injection molding, the grooves for generating hydro-dynamic fluid was separated by forced drawing from a core pin which formed the grooves for generating hydro-dynamic fluid.
When the inside diameter of the cylindrical portion is less than 2 mm, the load capacity of the bearing becomes small not to be suited for the use as a hydro-dynamic fluid bearing. When the inside diameter is more than 5 mm, it becomes difficult to maintain the accuracy of the inside diameter surface of the cylindrical portion. The inside diameter of the cylindrical portion is thus adequate within the range of 2 to 5 mm. As for the thickness of the cylindrical portion, when the thickness of the resin is less than 0.8 mm, pressure inclination is generated in the axial direction (the longitudinal direction) at the time of injecting the resin so that the inside diameter surface is formed in a taper shape. When the thickness is more than 2.0 mm, the influence of sink marks and orientation properties of the resin is considerable so that the roundness and the generant shape become bad. The thickness of the cylindrical portion is thus adequate within the range of 0.8 to 2 mm.
It is desirable that the resin material includes polyphenylene sulfide resin, carbon fibers and one or more fillers other than the carbon fibers, the total content of the fillers including the carbon fibers is 20 to 50 wt. %, and the melt index of the resin material is 4 to 9 g/min. at the temperature of 300° C. and the load of 5 kg. Instances of other fillers than the carbon fibers are graphite, molybdenum disulfide, fluororesin, spherical silica and phenolic resin.
The nearly central portion of the outer surface of the bottom portion is the portion that the resin material lastly flowed in a mold at injection molding. At injection molding, the grooves for generating hydro-dynamic fluid was separated by forced drawing from a core pin which formed the grooves for generating hydro-dynamic fluid. Thus, no weld mark is generated and the mold structure becomes simple. By selecting the above dimensions of the hydro-dynamic fluid bearing, the processing becomes easy and the number of parts can be decreased so the hydro-dynamic fluid bearing can be manufactured at low cost.
The hydro-dynamic fluid bearing uses resin which is superior in slidability and wear resistance. The hydro-dynamic fluid bearing is superior in durability since it is strong to impacts when touching the shaft at times of start and stop.
The hydro-dynamic fluid bearing is manufactured by injection molding. As molding material for the hydro-dynamic fluid bearing, one or more fillers in addition to carbon fibers are filled to polyphenylene sulfide resin. The total content of the fillers including the carbon fibers is 20 to 50 wt. %. When the total content is less than 20 wt. %, mold shrinkage becomes large so that the accuracy can not be insured. Further, the strength can not also be insured. When the total content is more than 50 wt. %, flowability becomes bad so that the accuracy can not be insured.
The melt index is 4 to 9 g/min. (measured at the temperature of 300° C. and the load of 5 kg). When the melt index is less than 4 g/min., the flow becomes bad so the necessary accuracy can not be obtained. When the melt index is more than 9 g/min., mold shrinkage becomes large so the necessary accuracy can not be obtained. By selecting the above wt. % of the fillers, it becomes possible to manufacture a hydro-dynamic fluid bearing in high accuracy.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of the first embodiment of the present invention;
FIG. 2 is a cross-sectional view of the second embodiment of the present invention;
FIG. 3 is a cross-sectional view of the third embodiment of the present invention;
FIG. 4 is a cross-sectional view of the fourth embodiment of the present invention;
FIG. 5 is a cross-sectional view of the fifth embodiment of the present invention;
FIG. 6 is an illustrative view of a stator a part of which is cut out;
FIG. 7 is a cross-sectional view of the sixth embodiment of the present invention;
FIG. 8 is a cross-sectional view of the seventh embodiment of the present invention;
FIG. 9 is a vertically cross-sectional view of the eighth embodiment of the present invention;
FIG. 10A is measurement data of the roundness in a hydro-dynamic fluid bearing device of the eighth embodiment of the present invention;
FIG. 10B is measurement data of the processing accuracy in relation to shape;
FIG. 11 is a vertically cross-sectional view of the principal part of an instance of a mold for injection molding for a hydro-dynamic fluid bearing device of the present invention;
FIG. 12 is a cross-sectional view of an instance of a prior art bearing device; and
FIG. 13 is a cross-sectional view of another instance of a prior art bearing device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, embodiments of the present invention will be described with reference to drawings. FIG. 1 shows a cross-sectional view of a motor 1 including a hydro-dynamic fluid bearing device of the first embodiment of the present invention.
In the motor 1 of this embodiment, a bearing member 4 made of resin is integrally formed so as to have a cylindrical radial bearing surface 6 provided with grooves 5 for generating hydro-dynamic fluid in a cylindrical hole 2, and a thrust bearing surface 7 which is connected to the radial bearing surface 6. The radial bearing surface 6 is a hydro-dynamic fluid bearing surface and the thrust bearing surface 7 is a sliding bearing surface. A lubricant is disposed in the cylindrical hole 2 as a lubricant fluid. The outer circumferential surface of the bearing member 4 is fixed by adhesion to a metal housing 3 which is an annular member. A shaft 16 is inserted in the bearing member 4 so as to be rotatable. A stator 9 is fixed to the outer circumferential surface of the metal housing 3. The metal housing 3 is fixed to a base (or a print circuit board) 10 with a screw 11. The stator 9 has coils 12. A rotor 14 is disposed outside in the radial direction of the stator 9 so as to be opposite to the stator 9. The rotor 14 is fixed to the shaft 16 through a yoke 13. The rotor 14 and the stator 9 constitute a drive mechanism of the motor 1 including the hydro-dynamic fluid bearing device.
In the hydro-dynamic fluid bearing device constructed as described above, since the bearing member 4 is fixed by adhesion to the metal housing 3 which has the higher rigidity than the bearing member 4, so as to reinforce the cylindrical portion 4a of the bearing member 4, the bending displacement (bending elastic deformation) of the bearing member 4 does not occur even if there is the large unbalance load in the rotor 14 and the large centrifugal force (radial load) attending the rotation of the rotor (shaft) acts upon the bearing member 4.
The outer circumferential surface of the bearing member 4 may be fixed by adhesion to the metal housing 3 either through the entirety in the axial direction of the bearing member 4 or only through the upper portion of the bearing member 4. In the case of the fixture only by adhesion at the upper portion, because a small flange 21 which is formed at a level near the bottom of the bearing member 4 is fixed to the housing 3 by the manner that both side surfaces in the axial direction of the flange 21 is pressed in the axial direction of the bearing member 4 by fastening the housing 3 to the base 10 with the screw 11, the outer circumferential surface of the bearing member 4 is fixed to the housing 3 at two portions of its upper and lower portions to obtain the sufficient reinforcement for the bending displacement of the bearing member 4.
Although the bearing member 4 made of resin is inferior in flexural rigidity to metal, the friction is low and the wear resistance is good and it can be manufactured at low cost by injection molding. It becomes possible to provide a hydro-dynamic fluid bearing device of high rigidity, low friction, good durability and low cost by compensating the lack of the flexural rigidity of the cylindrical portion 4a of the bearing member 4. The radial load and the thrust load can be born by one bearing member 4 having the thrust bearing surface 7 which is a convex spherical surface and the radial bearing surface 6.
FIG. 2 shows the second embodiment.
Features different from the first embodiment are that the flange 21 of the bearing member 4 made of resin is larger in the radial direction than that of the first embodiment, and the base 10 is sandwiched by the upper surface of the flange 21 of the bearing member 4 and the lower surface of a flange 20 of the housing 3, and the base 10 and the bearing member 4 are fixed to the housing 3 with the screw 11. The bearing member 4 may be fixed by adhesion to the annular metal housing 3 either through the entirety in the axial direction of the outer circumferential surface of the bearing member 4 or only through the upper portion of the outer circumferential surface of the bearing member 4, like the first embodiment. When the screw 11 is disposed so as not to protrude in the axial direction from the bearing member 4, there is an advantage that a thin bearing device can be obtained without changing the length of the bearing member 4.
Other operations and effects are similar to those of the first embodiment.
FIG. 3 shows the third embodiment.
Features different from the first embodiment are that the flange 21 of the bearing member 4 is sandwiched by the base 10 and the flange 20 of the housing 3, and the base 10 and the bearing member 4 are fixed to the housing 3 with the screw 11. The number of steps for processing the housing 3 is smaller than that of the first embodiment and the thickness accuracy of the flange 21 of the bearing member 4 is not required. Because the flange 21 of the bearing member 4 is directly fixed to the housing 3, the strength of the fixture with the screw is higher than that of the second embodiment.
Other operations and effects are similar to those of the first embodiment.
FIG. 4 shows the fourth embodiment.
Features different from the third embodiment are that the diameter of the outer circumferential surface of the bearing member 4 is smaller at a portion 4c near a cylindrical opening than at the other portion, and the portion 4c is fixed to the annular housing 3 by adhesion or firm insertion.
Generally, when the outside diameter surface of the bearing member 4 made of resin is firmly inserted, the interference of the outside diameter affects the shrinking quantity of the inside diameter. The shrinking quantity of the inside diameter is 80 to 100% of the interference of the outside diameter though it varies in accordance with the ratio of the inside diameter to the outside diameter (d/D) and the quality of the material. It is thus impossible to insure the accuracy of the inside diameter of the bearing member 4 made of resin which is required for a hydro-dynamic fluid bearing. Accordingly, in this embodiment, the metal housing 3 is in contact with the portion 4c near the opening which is an outside diameter portion corresponding to a lubricant reservoir 8 (the inside diameter of the lubricant reservoir 8 is larger than that of the other portion of the cylindrical hole 2 to insure the quantity of a lubricant enough for improving the durability). Thus, the radial bearing surface 6 is not affected. In the bearing member 4, since the portion for firm insertion is thinner than the other portion, the affection of the pressure in the axial direction can be decreased. Thus, the bearing member 4 can be fixed to the housing 3 by firm insertion without decreasing the required accuracy of the radial bearing surface 6.
Since the accuracy of the outside diameter of the bearing member 4 is required merely at the portion 4c (small diameter portion) near the opening for firm insertion, the processing of the bearing member 4 is easy.
Other operations and effects are similar to those of the third embodiment.
FIG. 5 shows the fifth embodiment.
Features different from the third embodiment are that there is no housing and the bearing member 4 made of resin is directly fixed to the inner circumferential surface of the stator 9 which is an annular member as shown in FIG. 6. The flange 21 of the lower portion of the bearing member 4 is sandwiched and pressed by the stator 9 and the base 10 and is fixed to the stator 9 and the base 10 with a screw 11. The upper portion and the middle portion of the bearing member 4 are directly fixed to the stator 9 by adhesion. There are advantages that the number of parts is decreased and assembling becomes easy.
Other operations and effects are similar to those of the third embodiment. The stator 9 which constitutes the drive mechanism of the motor 1 including the hydro-dynamic fluid bearing device, is an annular member made of steel. The rigidity of it is larger than that of the bearing member 4 made of resin. The inner circumferential surface of the stator 9 is annular.
FIG. 7 shows the sixth embodiment.
Features different from the fifth embodiment are that a filler 30 is disposed in a gap between the upper portion of the outer circumferential surface of the bearing member 4 and the inner circumferential surface of the stator 9 so as to fix the stator 9 and the bearing member 4 to each other. Although the bearing member 4 and the stator 9 are not fixed to each other by adhesion, the bearing member 4 can be sufficiently reinforced by filling the gap between the bearing member 4 and the stator 9 with the filler 30.
Other operations and effects are similar to those of the fifth embodiment.
This embodiment is not restrictive, and the bearing member 4 may be reinforced by the manner that two portions of both end portions in the axial direction of the outer circumferential surface of the bearing member 4 are fixed to an annular member the rigidity of which is larger than that of the bearing member 4.
The present invention may be a combination in which some of the first to sixth embodiments are combined in an ordinary manner. The outer circumferential surface of the bearing member 4 may be reinforced by the manner that it is mounted to the rotor 14 which is an annular member made of steel and constitutes the drive mechanism of the motor including the hydro-dynamic fluid bearing device. The rigidity of the rotor 14 is larger than that of the bearing member 4 made of resin. In that case, the bearing member 4 rotates.
The bearing member 4 in which the radial bearing surface 6 having grooves 5 for generating hydro-dynamic fluid requires a high accuracy is manufactured by injection molding. If the flange 21 extending outwards in the radial direction from the outer circumferential surface of the bearing member 4 is positioned at the same level of the portion 4c near the opening of the cylindrical hole 2 or the middle portion in the axial direction, the inner circumferential surface of the cylindrical hole 2 can not be accurately formed due to sink marks by the influence of the difference of the thickness in the radial direction of the bearing member 4. Therefore, the flange 21 is formed at the level near the bottom portion of the bearing member 4. The influence of the difference of the thickness of the bearing member 4 which the inner circumferential surface of the cylindrical hole 2 receives is thus decreased so the inner circumferential surface of the cylindrical hole 2 is accurately formed. The rigidity of the bearing member 4 increases by the manner that the bearing member 4 is fixed to the annular member. The bearing member 4 is not provided with the flange 21.
Next, FIG. 8 shows a cross-sectional view of a bearing device according to the seventh embodiment of the present invention. A rotational member includes a shaft 101, a disk attachment flange 106 and a rotor 103. A supporting member for supporting the rotational member includes a stator 104, a base 102 and a bearing member 105.
Because the fundamental structure of the rotational member is the same as that of the prior art bearing device shown in FIG. 12, the description will be omitted. As the quality of the material for the shaft 101 in the bearing device according to this embodiment, a stainless steel of SUS 440C treated by heat which is generally used is employed. But the quality of the material for the shaft 101 used in a bearing device of the present invention is not limited if the condition of the diameter of 2 to 5 mm of the shaft which is a necessary condition of the present invention is satisfied.
The fundamental structure of the supporting member for supporting the rotational member is also the same as that of the prior art bearing device shown in FIG. 12. But, since the shape and so on of the bearing member differ from those of the prior art bearing device, those points will be mainly described.
In the bearing device of the present invention, a flange 105c of the bearing member 105 is disposed below a cylindrical portion of the bearing member 105. Thus, in the bearing member, the positions in the axial direction of the portion of the grooves for generating hydro-dynamic fluid and the flange are different from each other. By this structure, at the injection molding of the bearing member of resin, it is prevented to decrease the accuracy of the portion of the grooves for generating hydro-dynamic fluid due to an influence of the flange 105c.
In the prior art bearing device, the thrust bearing surface of the thrust bearing is formed by the manner that a steel ball which is the thrust receiving member is tightly inserted in the bearing member. But, in the present invention, the bearing member 105 is provided with the thrust bearing surface, the central portion of which is a convex spherical surface 105d.
By this structure, the convex portion can be formed in the bearing device at the same time as the injection molding of the bearing member of resin. Thus, the process of inserting tightly the steel ball for the thrust receiving member in the bearing member can be omitted so it becomes possible to improve the workability of assembling.
A base 102 made of metal such as aluminum die cast and zinc die cast is used. As shown in FIG. 8, the cylindrical portion 105e of the bearing member 105 is fixed on a cylindrical portion 102a of the base 102. The flexural rigidity of the bearing member 105 made of synthetic resin is thus strengthened. In this case, particularly, since the long cylindrical portion 102a of the base 102 is disposed along the cylindrical portion 105e of the bearing member, the flexural rigidity of the bearing member 105 made of synthetic resin is strengthened.
In the bearing device of the present invention, for strengthening the flexural rigidity of the bearing member of the fluid bearing, it is also possible that the cylindrical portion 105e having the radial bearing surface of the bearing member is made of copper group metal such as free-cutting brass and phosphorus bronze, and a thrust receiving member having a thrust bearing surface is fixed to the bearing member. The thrust receiving member may be a thrust plate made of ceramics or the like. In this structure, the strength of the flexural rigidity of the bearing member 105 can be insured even without a long cylindrical portion 102a of the base 102.
When an adhesive fills up between the cylindrical portion 105e of the bearing member and the cylindrical portion 102a of the base, the flexural rigidity of the bearing member 105 becomes stronger. The supporting member for supporting the rotational member is completed by the manner that a stator 104 is assembled in the cylindrical portion 102a of the base by firm insertion or the like.
Next, the structure of the cylindrical portion 105e of the bearing member will be described. In the inner circumferential surface of the cylindrical portion 105e of the bearing member, radial bearing surfaces 105a are formed at two portions which are distant from each other in the axial direction. Herringbone-shaped grooves for generating hydro-dynamic fluid are formed in each radial bearing surface 105a. A shaft 101 disposed in the bearing member 105 has cylindrical radial receiving surfaces 101a which are opposite to the radial bearing surfaces 105a through a lubricant in a radial bearing gap 107, respectively.
The radial bearing gap 107 is established so as to meet the condition of 3.5 to 10 μm which is a necessary condition of the present invention. If it is out of the range, the load capacity becomes small or the dynamic torque becomes large.
The lower end surface of the shaft 101 has a thrust receiving surface 101b opposite to a thrust bearing surface 105b through the lubricant. The thrust bearing surface 105b is a convex spherical surface so as to be in a point contact with the thrust receiving surface 101b for decreasing the contact area between them.
A fluoric oil which has the kinematic viscosity of 20 to 200 cSt at 40° C. is disposed as a lubricant between the radial bearing surface 105a and the radial receiving surface 101a and between the thrust bearing surface 101b and the thrust receiving surface 105b.
Next, the operation of the bearing device of the present invention will be described. But since the fundamental operation is the same as that of the prior art bearing device, an outline of the operation will be merely described. When the stator 104 is electrified, a rotating magnetic field is generated. The rotor 103 thereby rotates together with the shaft 101 and the disk attachment flange 106. When the rotational member constituted by the shaft 101, the rotor 103 and so on rotates, the thrust bearing surface 101b rotates in point contact state with the thrust receiving surface 105b through the lubricant.
The thrust bearing surface 101b and the thrust receiving surface 105b constitute a sliding bearing by such point contact. At this time, since the lubricant flows in the thrust bearing gap 108 between the thrust bearing surface 101b and the thrust receiving surface 105b, and they are in point contact with each other through the lubricant, the boundary lubrication properties are improved to decrease the abrasion of the thrust bearing surface 101b and the thrust receiving surface 105b.
While the thrust receiving surface 105b is in point contact with the thrust bearing surface 101b and rotates relatively to the latter, the pressures of the lubricant in the radial bearing gaps 107 between the radial bearing surfaces 105a and the radial receiving surfaces 101a increase because of a pumping effect by the grooves for generating hydro-dynamic fluid, respectively. The radial bearing surfaces 105a rotate in non-contact state with the radial receiving surfaces 101a. Although the rotational operation starts, in the case of the structure of the bearing device of the present invention, the flexural rigidity of the shaft can be insured and it becomes possible to suppress the increase of the torque at a low temperature.
For improving boundary lubrication properties and leakage properties of the lubricant, the fluoric oil includes perfluoropolyether having a carboxylic acid at its termination which is mixed by 0.1 to 10 wt. %.
In the bearing device of the present invention, considering the lack of corrosion resistant properties of fluoric oil, stainless steel is used as the material of the shaft and plastics is used for the bearing member. For improving the slidability at the time of start and stop, PPS (polyphenylene sulfide resin) including carbon fibers and Teflon can be used as the material of the bearing member. In this invention, taking it the other way round, it is also possible to rotate the bearing member 105 which is born by the shaft 101.
The eighth embodiment of the present invention is shown in FIG. 9.
FIG. 9 is a vertically cross-sectional view of a hydro-dynamic fluid bearing member 310 according to the present invention in which the radial bearing and the thrust bearing are integrated with each other.
First, the structure will be described. In the hydro-dynamic fluid bearing member 310, a cylindrical portion 307 and a bottom portion 308 integral with the cylindrical portion 307 are formed into one body of a resin material by injection molding. A cylindrical bearing hole 310a the central axis of which extends in the vertical direction is formed inside of the hydro-dynamic fluid bearing member 310. The upper end of the bearing hole 310a is open to communicate the exterior. The lower end of the bearing hole 310a is closed to form a bottom surface. A flange 310b provided with through holes 310c for bolts which are utilized when a stator and so on are fixed to the hydro-dynamic fluid bearing member 310 is formed integrally with the outer circumferential surface of the bottom portion 308 of the hydro-dynamic fluid bearing member 310.
In the inner circumferential surface of the bearing hole 310a, cylindrical radial bearing surfaces 312 are formed at two portions which are distant from each other in the axial direction. Grooves 311a and 311b for generating hydro-dynamic fluid are formed in the radial bearing surfaces 312, respectively. Thus the cylindrical portion 307 has the grooves 311a and 311b for generating hydro-dynamic fluid in the inner surface. Both ends of the radial bearing surfaces 312 in the radial direction (vertical direction in FIG. 9) are respectively connected to oil reservoirs 314a, 314b and 314c of annular groove shapes which are utilized for improving the durabilities of the radial bearing surfaces 312 by supplying an oil as a lubricant fluid to the radial bearing surfaces 312. These oil reservoirs 314a, 314b and 314c are continuous in the circumferential direction, respectively. The oil reservoirs 314a and 314b communicate with the upper and lower ends of the grooves 311a for generating hydro-dynamic fluid, respectively. The oil reservoirs 314b and 314c communicate with the upper and lower ends of the grooves 311b for generating hydro-dynamic fluid, respectively.
At injection molding, the oil reservoirs 314a, 314b and 314c and the grooves 311a and 311b for generating hydro-dynamic fluid are separated by forced drawing from a core pin which formed them. Thus, the depth h1 of the oil reservoirs 314a, 314b and 314c is nearly equal to the depth h0 of the grooves 311a and 311b.
In the present invention, also the oil reservoirs can be easily formed. For instance, they can be formed in the hydro-dynamic fluid bearing merely by processing protruded portions for forming the oil reservoirs, on the outer circumferential surface of a cylindrical core pin in addition to protruded portions for forming the grooves for generating hydro-dynamic fluid.
At the time of injection molding of resin, the portion near the opening end of the bearing hole 310a and the portion near the flange 310b of the inner circumferential surface of the cylindrical portion 307 are apt to be affected by orientation properties and the rate of solidification in comparison to the other portion of the inner circumferential surface of the cylindrical portion 307. Thus, those portions are apt to be inferior in the molding accuracy to the other portion of the inner circumferential surface of the cylindrical portion 307. Accordingly, by forming the oil reservoirs which are not so required the processing accuracy are formed in such portions as apt to inferior in the molding accuracy, the problems of the processing accuracy can be solved and the quantity of the lubricant enough for improving the durability is insured.
As for dimensions of the hydro-dynamic fluid bearing member 310 according to this embodiment, considering the accuracy and the strength, the inside diameter of the cylindrical portion 307 is 3 mm, the outside diameter is 5.5 mm and the thickness is 1.25 mm. The length in the axial direction of the hydro-dynamic fluid bearing member 310 is 12 mm, and the depth of the bearing hole 310a is 10 mm. The thickness of the flange 310c is 1.5 mm in consideration of the strength at the fixture.
FIG. 10A shows measurement data of the roundness. In the drawing, 10A represents a measurement result of the roundness where the inside diameter surface of the cross-section of the cylindrical portion of the hydro-dynamic fluid bearing member along a line 10A--10A in FIG. 9 is measured. 10A' represents a measurement result of the roundness where the inside diameter surface of the cross-section of the cylindrical portion of the hydro-dynamic fluid bearing member along a line 10A'--10A' in FIG. 9 is measured. It is realized that the roundness is less than 2 μm in either of 10A and 10A'. FIG. 10B shows results where the shape of the bearing hole of the cylindrical portion of the hydro-dynamic fluid bearing member is measured in the axial direction. In the drawing, 10B and 10B' represent results from points 10B and 10B' in FIG. 9, respectively, where the shape of the inside diameter surface is measured in the axial direction from the bottom portion to the opening end along the inside diameter surface of the bearing hole. The depth of the grooves for generating hydro-dynamic fluid and the depth of the oil reservoirs are 9 to 11 μm and the accuracy of the depth is less than 2 μm. The accuracy of the shape is less than 2 μm throughout the inside diameter surface. As realized from the above results, as for either of the roundness and the shape, the hydro-dynamic fluid bearing according to the present invention satisfies enough the necessary accuracy for hydro-dynamic fluid bearing.
When the inside diameter of the cylindrical portion 307 is 2 to 5 mm and the thickness of the cylindrical portion 307 is 0.8 to 2.0 mm, a nearly equal accuracy could be obtained.
Since the hydro-dynamic fluid bearing is superior in the slidability and the durability, it is possible to reduce impacts and damages when touching the shaft at the time of start and stop. The wear resistance of the bottom portion which is especially apt to suffer abrasion is superior.
In the case of forming two herringbone patterns of grooves as a groove pattern formed in the cylindrical portion 307 constituting the radial hydro-dynamic fluid bearing as the embodiment, non-symmetric grooves may be formed so that the widths a' and b' in the axial direction outside of bending portions are larger than the widths a and b in the axial direction inside of the bending portions, respectively. By pumping effects of such non-symmetric grooves, even if the dimensional accuracy or the shape of the inner surface of the cylindrical portion is slightly bad, the flow of a lubricant fluid is forcedly introduced to the middle portion of the hydro-dynamic fluid bearing. Thus, the lubricant fluid is prevented from leaking out of the hydro-dynamic fluid bearing so it is desirable for insuring the durability. The groove pattern is not limited to the embodiment. It may be one herringbone pattern. A pattern or patterns other than the herringbone pattern may be used. Since the groove pattern can be determined merely in accordance with the pattern of protrusions for forming grooves for generating hydro-dynamic fluid, which is processed in a core pin of a mold for forming the bearing hole 310a, any pattern can be easily manufactured.
In the bottom portion 308 constituting the thrust bearing portion, the central portion of the thrust bearing surface 313 of the bottom surface of the bearing hole 310a is formed into a convex spherical surface. Since it is in point contact with the end surface of the shaft inserted in the bearing hole 310a, the friction torque at a rotation is kept from increasing. In the case of a large axial load, grooves for generating hydro-dynamic fluid may be formed in the thrust bearing surface 313 so as to generate a lifting force by a hydro-dynamic fluid effect attending on rotation. The abrasion of the thrust bearing surface is thereby reduced. A protrusion having a flat surface at the top may be formed in the thrust bearing surface 313 in place of the convex spherical surface. It is also possible that the thrust bearing surface 313 is flat and the end surface of the shaft opposite to the thrust bearing surface 313 is spherical. After all, the thrust bearing surface 313 can have any shape if the friction is low when rotating and the partial contact with the shaft can be avoided. Similarly in the case of manufacturing the groove pattern of grooves for generating hydro-dynamic fluid or the oil reservoirs, since the shape of the thrust bearing surface 313 can be selected merely by processing an end surface of a core pin of a mold for forming the bearing hole 310a, any shape can be easily manufactured.
FIG. 11 shows an instance of a mold for injection molding for a manufacturing method of a hydro-dynamic fluid bearing of the present invention (a vertically cross-sectional view of the principal part).
The mold is a three-plates mold. The fixed side comprises a spoor bush 421, a fixed side attachment plate 423 to which a runner lock pin 422 is attached, a runner stripper plate 424, a fixed side mold plate 426 having a fixed side cavity 425, and so on. The fixed side cavity 425 is provided with a runner 427, a gate 428 and a recessed portion 425a for forming a bottom portion of a hydro-dynamic fluid bearing.
The movable side comprises a movable side mold plate 430 having a movable side cavity 429, and so on. The movable side cavity 429 is provided with recessed portions 429a and 429b for forming a flange and a cylindrical portion of a hydro-dynamic fluid bearing, respectively. Further, there is provided a core pin 431 for forming a radial bearing surface, which has grooves for generating hydro-dynamic fluid, of a cylindrical portion of a hydro-dynamic fluid bearing, and a thrust bearing surface 313, which is connected to the radial bearing surface, of a bottom portion of the hydro-dynamic fluid bearing.
The other parts of the movable side (a guide pin, a support pin, a spacer block, a movable side attachment plate, an ejector plate to which an ejector pin is attached, a return pin, a spring and so on) and a tension link for operating the three plates, a plug bolt, a stop bolt, a heater for controlling the temperature of the mold, and so on are omitted in the drawing.
When a hydro-dynamic fluid bearing is formed by injection molding using the above mold, molten resin injected from an injection nozzle of an injection molding machine into the mold flows through a spoor 432 and the runner 427 and flows into the recessed portion 425a, which is formed in the fixed side cavity 425, for forming a bottom portion of the hydro-dynamic fluid bearing, from the one point pinpoint gate 428 provided nearly at the center of the recessed portion 425a. The resin flowing into the recessed portion 425a is filled in the recessed portion 425a. The resin is then filled in the recessed portion 429a of the movable side cavity 429 uniformly in the circumferential direction of the recessed portion 429a. After this, the resin is filled in the recessed portion 429b. Since the resin is filled from the one point pinpoint gate 428 nearly at the center of the recessed portion 425a, when filling in the recessed portion 429b for forming a cylindrical portion of the hydro-dynamic fluid bearing, the leading portion of the molten resin flows to the axial direction of the recessed portion 429b uniformly in the circumferential direction. Thus, no weld mark is generated and the injection pressure is applied uniformly. The nearly central portion 440 of the outer surface of the bottom portion of the hydro-dynamic fluid bearing is the portion that the resin material lastly flows in the mold at the injection molding. Thus, a mark of gate remains. Since there is used the material for molding in which carbon fibers and one or more fillers other than the carbon fibers are filled to polyphenylene sulfide resin, the total content of the fillers is 20 to 50 wt. %, and the melt index of the material is 4 to 9 g/min. (measured at the resin temperature of 300° C. and the load of 5 kg), high accuracies (the roundness, the generant shape, the cylindrical degree, and the dimensional accuracy) can be obtained.
After keeping pressure and cooling, by the separation of the mold of the molding machine, the mold is opened between the fixed side mold plate 426 and the runner stripper plate 424. The portion of the gate 28 is cut so that a hydro-dynamic fluid bearing (product) remains in the fixed side cavity 429, and a spoor and a runner remain on the runner stripper plate 424. Next, the mold is opened between a PL (parting line) 433 and the runner stripper plate 424 and between the runner stripper plate 424 and the fixed side attachment plate 423. The separation of the hydro-dynamic fluid bearing from the movable side cavity 429 is performed by the manner that the flange surface is pushed out by the ejector pin 434. Thus, grooves for generating hydro-dynamic fluid are separated from the core pin 431 which formed the grooves for generating hydro-dynamic fluid, by forced drawing by utilizing the elastic deformation of resin. Since the grooves for generating hydro-dynamic fluid are separated from the core pin to the axial direction by forced drawing, the structure of the mold can be simplified. Since the shape and the pattern of the grooves for generating hydro-dynamic fluid can be determined merely by processing the corresponding shape and pattern to the core pin, the freedom of the design of the grooves for generating hydro-dynamic fluid increases.
The position for pushing out a hydro-dynamic fluid bearing is not limited to this embodiment. The end surface around the opening of the hydro-dynamic fluid bearing may be pushed out by an ejector pin or a sleeve.
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A novel hydro-dynamic fluid bearing device is herein disclosed which comprises a cylindrical shaft, a substantially cylindrical bearing member for axially supporting the shaft rotatably in a cylindrical hole having a bottom surface, a supporting member fixed on one side of the shaft and the bearing member, and a rotation member fixed on the other side of the shaft and the bearing member and rotatably supported on the supporting member, grooves for generating hydro-dynamic fluid being formed on at least one of the outer peripheral surface of the shaft and the inner peripheral surface of the cylindrical hole of the bearing member, wherein the bearing member is made of a resin material, and the outer peripheral surface of the substantially cylindrical portion is fixed to an annular reinforcing member having a higher rigidity than the bearing member.
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FIELD OF THE INVENTION
The invention relates to respiratory-analysis mattresses and systems, and to methods of use thereof.
The invention further relates to the measurement of respiratory, cardiac and other movement related functions in patients suffering from a range of respiratory syndromes, including the disordered breathing associated with Cheyne Stokes syndrome, anaesthetic induced partial respiratory obstruction and sleep apnea.
BACKGROUND OF THE INVENTION
Sleep apnea is a respiratory syndrome known to be present in about 8% of the adult male human population and 4% of the adult female human population.
The syndrome manifests itself as the repetitive cessation of, or large reduction in, breathing while the patient is asleep—respectively termed apneas and hypopneas. Apneas may be divided further into central apneas, where the cause of the apnea is the failure of the nervous system to activate the muscles responsible for respiration, and obstructive apneas, where the patient tries to breath but is prevented from doing so by the temporary collapse on inspiration of his or her upper airway. The reasons for such collapses are not completely understood but may include a loss of tone in those muscles which hold the airway open plus an anatomical disposition towards a narrow upper airway.
Prior to treatment the syndrome must be diagnosed. Conventionally, this is performed by an overnight study in a specialised sleep clinic, connecting the patient to electrophysical and respiratory measurement equipment to monitor physiological variables such as the electroencephalogram, blood oxygen saturation, heartrate, chest wall movement, and respiratory air flow during the various stages of sleep.
The attachment of the such monitoring equipment requires skilled staff and is often disruptive to the patient's sleep. Furthermore, the recording of all the physiological variables requires considerable computing power and the subsequent analysis, although assisted by computer, still requires considerable attention by the staff.
Monitoring of the patient's sleep in the patient's home traditionally uses a simplified form of the above-mentioned equipment which still may be complex and disruptive to the patient's sleep.
The measurement of less disruptive variables which correlate well with the traditional ones has been pursued as a way of making such sleep studies simpler to perform and less disruptive to the patient.
A device used in this area is the Static Charge Sensitive Bed (SCSB) described in U.S. Pat. No. 4,320,766 (Allihanka et al). U.S. Pat. No. 4,320,766 describes a mattress which outputs a single electrical signal that varies with the patient's movement. By suitable electrical filtering of the movement signal indications of body movement, respiration, snore and heartbeat are produced for subsequent display.
The SCSB principle was extended by Crawford and Kennard in their published UK patent application, GB 2 166 871 A (1984), for a Respiration Monitor. Here, strips of polyvinylidene fluoride (PVDF) were assembled in a common, parallel connection in order to give area coverage of a patient's respiratory movement. PVDF is a piezo-electric plastics material readily available in strips and sheets of minimal thickness.
A PVDF sensor has also been used in a device described by Siivola [Siivola J., (1989) New noninvasive piezoelectric transducer for recording of respiration, heart rate and body movements. Med. & Biol Eng. & Comput. 27, 423-424].
The clinical use of the SCSB is extensively described in the PhD thesis of Dr O. Polo (Dept of Physiology, University of Turku, Finland) republished as a supplement in Acta Physiologica Scandinavica Vol 145, Supplementum 606, 1992.
A PVDF film based device for detecting and recording snoring is also described in International Publication No. WO 96/36279 (Sullivan).
A limitation of the SCSB is that because of its inherent planar construction it cannot be used to localise the source of the movement it detects. Likewise, the above-mentioned devices also generate minimal spatial information. A major consequence of this is that the outputs of the said devices vary considerably with patient orientation. This limits the accuracy of information that can be derived from them.
DISCLOSURE OF THE INVENTION
The invention seeks to provide a respiratory-analysis mattress and system and associated method which overcome or at least ameliorates some of the deficiencies of the prior art.
According to the invention there is provided a mattress for monitoring patient movement for a patient lying on the mattress, the mattress including at least a plurality of independent like movement sensors for measuring movement at different locations on the mattress to generate a plurality of independent movement signals.
Preferably, the respiratory-analysis mattress includes the range three to ten such movement sensors.
Preferably, the movement sensors are formed by piezoelectric elements, for example polyvinylidene fluoride (PVDF) sensor strips.
Conveniently, at least some of said piezoelectric elements are arranged to measure lateral strain across the mattress, and preferably substantially parallel to each other.
In one embodiment of the invention, the mattress comprises a compressible filling surrounded by an outer (not necessarily outermost) layer, and the piezoelectric elements are attached, preferably by adhesive, to an inside surface of the outer layer.
Alternatively, the elements are laminated between two thin conformable elastic sheets.
In another embodiment of the invention the mattress takes the form of a thin movement-sensitive sheet, in which each piezoelectric element is enclosed within a waterproof envelope of material.
Such a movement-sensitive sheet can be mounted on a carrier sheet adapted to be placed over a conventional mattress.
Conveniently, each piezoelectric element is connected to a separate transition connector, which may for example be a printed circuit board (PCB), in such a manner as to avoid strain between the element and the transition connector during use of the mattress.
Alternatively, the piezoelectric elements can be connected to a single bus transition connector, which may for example be a single bus board.
In a further embodiment of the invention, said piezoelectric elements are integrally formed from a single composite sheet of piezoelectric material.
The piezoelectric material may be PVDF.
In this case, the piezoelectric elements can be formed by forming a series of staggered parallel cuts in a sheet of piezoelectric material, in such a way that each piezoelectric elements is formed between two adjacent such cuts, and folding each piezoelectric element through an angle so that the piezoelectric elements become spaced from each other, while remaining integrally connected together by a connecting portion of said sheet of piezoelectric material.
Conveniently, said angle is substantially 90°.
In one embodiment, a strengthening portion of said sheet of piezoelectric material is folded, and attached to, said piezoelectric elements in order to hold the strips in position.
Preferably, each piezoelectric element is provided with upper and lower metallised surface layers which are arranged not to overlap on the folded portion of the element, thus ensuring that any strain on the folded portion of the element does not contribute to the electrical signal produced by the element.
The invention also provides a respiratory-analysis system comprising a mattress as described above connected to processing means for receiving and processing said movement signals to derive said respiratory variable(s). The diagnostic variables can include respiratory rate, respiratory phase, respiratory effort and maximum respiratory rate.
Preferably, the output signals from each movement sensor are separately and independently processed. The resulting processed information may subsequently be combined by the computing means during further processing.
Preferably, each piezoelectric strip is connected to the computing means via a sensor buffer comprising an operational amplifier operating as a charge amplifier, wherein the input of the operational amplifier is protected against high voltage transients, which may be produced by the piezoelectric strip, by means of a resistor connected in parallel across the two inputs of the operational amplifier, said resistor having an impedance which is large compared with the input impedance of the virtual earth of the charge amplifier.
In addition a further resistor, having an impedance which is small compared to the output impedance of the piezoelectric strip, can be placed in series with the input of the operational amplifier.
Alternatively, two diodes can be connected in parallel, and in opposite directions, across the two inputs of the operational amplifier in order to limit the maximum voltage applied to the inputs of the operational amplifier.
The invention further provides that the processing means combined one or more of said respiratory variables to give one or more derived diagnostic variables.
The derived variables can include apnea classification, snore or obstructed breathing.
The invention further provides a method for monitoring patient movement for a patient lying on a mattress, the method comprising the steps of: measuring displacement due to body movement at a plurality of independent positions length-wise of a portion of the body to derive independent signals representative of respective individual body displacement at said positions.
The invention yet further provides a method for monitoring at least one respiratory variable for a patient lying on a mattress, the method comprising the steps of: measuring displacement due to body movement at a plurality of independent positions length-wise of a portion of the body to derive independent signals representative of respective individual body displacement at said positions; and processing said movement signals to derive said respiratory variable(s).
The invention yet further provides a respiratory analysis system for monitoring at least one respiratory variable for a patient, comprising: input means to receive a plurality of signals indicative of patient movement; and processor means to process said receive signals to derive said respiratory variable(s).
The invention further provides the method may further comprise detecting the occurrence of non-respiratory sudden body movements by at least detecting high frequency components of the movement signals in the absence of diagnostic signals indicating obstructive or central apnea occurrence.
The method may further comprise determining the degree of obstructed breathing present by at least detecting the ratio of respiratory effort signal to respiratory displacement signal plus optionally the amplitude of the snore signal.
The method may further comprise controlling the output treatment pressure of a Continuous Positive Accuracy Pressure (CPAP) treatment machine on the basis of information obtained in preceding steps of the method.
Such control either occurs in real-time, that is as the respiration is being monitored, or retrospectively, where accumulated respiratory data is processed to determine the treatment pressure subsequently to be programmed into the CPAP machine.
The method may further comprise storing video information relating to the patient only for those periods during which an apnea has been detected as explained above.
The method may further comprise outputting any of the information obtained in preceding steps of the method to a display or printer, or to an analogue physiological input channel of a polygraph in such a way as to display information in alphanumeric form on the display of the polygraph.
BRIEF DESCRIPTION OF THE INVENTION
A number of 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 schematic overview of a respiratory-analysis system to be described below;
FIGS. 2 a and 2 b are respectively plan and side views of a movement-sensitive mattress forming part of the system;
FIG. 3 is a cross-sectional view through the movement-sensitive mattress;
FIG. 4 a is a cut-away schematic drawing of the movement-sensitive mattress showing the internal sensor strips;
FIGS. 4 b and 4 c are top views of further embodiments of movement-sensitive mattresses;
FIG. 5 illustrates the use of the movement-sensitive mattress to produce a multichannel electrical signal indicating the displacement of the patient's body near the sensor strips;
FIG. 6 illustrates a sequence of displacements of the patient's body associated with normal breathing;
FIG. 7 illustrates a sequence of displacements of the patient's body associated with disordered breathing;
FIGS. 8 a and 8 b are respectively schematic cross-sectional and plan views of one of the sensor strips;
FIGS. 9 a and 9 b show the connection means of a sensor strip respectively before and after connection of the sensor strip thereto;
FIGS. 10 a and 10 b show the connection means with the sensor strip attached, but respectively before and after attachment of a rigid pressure plate;
FIGS. 11 a and 11 b show the connection of a coaxial cable to the connection means;
FIG. 12 a shows the attachment of the sensor strip to the connection means;
FIG. 12 b is a cross-section taken along A—A′ in FIG. 12 a;
FIG. 13 shows an alternative embodiment in which the sensor strips are connected to a single bus board instead of to individual circuit boards;
FIGS. 14 a to 14 d show the connection of the sensor strip (via the coaxial cable shown in FIGS. 11 a and 11 b, but omitted from FIGS. 14 a to 14 d ) to four alternative embodiments of sensor buffers;
FIG. 15 shows the connection of the sensor strips to computing means via strip connection means, sensor buffers, gain stages, and an analog to digital converter;
FIG. 16 shows pre-processing means for deconvolving input digital signals to produce output pre-processed digital signals;
FIG. 17 illustrates the deconvolution of a channel by subtraction of a fraction of the signal on that channel from the two adjacent channels in order to sharpen the spatial response of the channels;
FIG. 18 a illustrates the calculation of diagnostic signals from the pre-processed digital signals using basic processing means followed by diagnostic processing means; FIG. 18 b-f show plots of cross correlation with historical time;
FIG. 19 shows the output of diagnostic signals to display means;
FIG. 20 shows the control of a Continuous Positive Airway Pressure (CPAP) flow generator by the new system;
FIG. 21 shows a polygraph input means connected to the computing means, for allowing diagnostic information to be displayed on a polygraph using a spare analogue input channel of the polygraph;
FIGS. 22 a and 22 b show graphs of voltage against time, and the tracing of symbols on the polygraph display;
FIG. 23 shows the output of alphanumeric forms of diagnostic variables to the polygraph display;
FIG. 24 shows an alternative means of providing a plurality of sensor strips, in which the sensor strips are integrally formed from a single PVDF sheet;
FIG. 25 shows conductive tracks on the embodiment of FIG. 24;
FIG. 26 a shows an alternative to the embodiment of FIGS. 24 and 25, in which the sensor strips, are cut from a narrower PVDF sheet and then folded through 90° as shown in the next figure;
FIG. 26 b shows the folding of the sensor strips through 90° while remaining integrally connected to a tail strip;
FIGS. 27 a and 27 b show an embodiment which is the same as that of FIG. 26, except that a broader tail strip is used, so that the tail strip can be folded beneath the sensor strips to provide greater support;
FIGS. 28 and 29 show conductive strips on the embodiment of FIG. 26;
FIG. 30 shows the metallisation on each side of one of the sensor strips;
FIG. 31 shows the sensor strips wrapped around one edge of a foam sheet FIGS. 32 a, 32 b and 32 c show movement-sensitive sheets comprising the embodiments of any of FIGS. 24 to 30 ; and
FIG. 33 shows the movement-sensitive sheet of FIG. 32 a mounted on a carrier sheet, which can be in the form of a conventional fitted sheet.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 gives an overview of a system 101 which measures the body movements of a reclining person and from those measurements determines parameters of his or her respiratory, cardiac and other movement-related functions. The aforesaid parameters can be used to diagnose a range of respiratory disorders, in particular those associated with sleep apnea. The system can be used both in a hospital and in a patient's home.
The system 101 comprises sensor means 102 which generates electrical signals in response to movement of a reclining person, interface means 103 which converts the said signals into a form that can be processed by the computing means 104 (FIG. 1 ). The computing means 104 processes the said signals to produce the above-mentioned respiratory and movement parameters which are then further combined to produce parameters diagnostic of respiratory disorders associated with various types of sleep apnea. The function of the computing means 104 is determined by the control means 105 , which is operated by medical staff who are directing the use of the system.
The aforesaid processing can be in real time, that is at the same time as the said signals are being recorded, or in a review process where the said recorded signals are recalled from storage and processed at some time after their acquisition.
Some or all of the diagnostic parameters can then be displayed using a display means 106 , recorded for subsequent review on computer disk by a recording means 107 , printed using a printing means 108 , transmitted to another location using a transmission means 109 and output to a recording polygraph by polygraph input means 110 . Additionally, if a particular preset condition of the diagnostic parameters is met a video camera 111 can be switched on to record moving or stationary video images of the patient's body position and movements. Alternatively, or optionally, a similar or different preset condition can activate an alarm means 112 to indicate to another person the occurrence of the said preset condition. An external Constant Positive Airway Pressure (CPAP) flow generator may optionally be controlled via CPAP control means 113 . Sound output means 114 may be used to listen to snore signals, either in real time or on subsequent replay of data.
The system can operate both in a real time mode, producing diagnostic parameters in immediate response to signals from the sensor means 102 or in a retrospective mode wherein the said signals are replayed from a computer disk and diagnostic parameters calculated at the time of replay.
Referring to FIGS. 2 a and 2 b, sensor means 102 comprises a movement-sensitive mattress 2 which can rest on top of a conventional mattress 3 on which the patient 1 lies. FIG. 2 b shows the movement-sensitive mattress 2 above the conventional mattress 3 , but this could alternatively be below the conventional mattress 3 . The patient's head may optionally rest on a pillow 4 .
As shown in FIG. 3, movement-sensitive mattress 2 comprises a sandwich of low density polyethylene foam 7 enclosed by a neoprene envelope 6 constructed in such a way that movements of the patient's body cause stretching of the neoprene envelope 6 .
Referring to FIG. 4 a, affixed to the inside surface of the top side of the neoprene envelope 6 are a number of sensor strips 5 , arranged in one or more patterns that span most of the patient's body. The patterns may run laterally across the movement-sensitive mattress as illustrated, or vertically from head to toe, or a combination or superposition of both. Electrical signals are conducted from the sensor strips 5 by sensor strip connectors 42 .
At a minimum, three sensor strips 5 arranged to be level with the patient's rib cage area are required to obtain useful electrical signals utilised for subsequent processing. A typical range is between three and ten sensors.
In FIG. 4 b, six sensor strips 5 ′ are arranged in a spaced-apart configuration. The sensor strips are formed in the same manner as those shown in FIG. 4 a, however are substantially shorter than the width of the mattress 2 . A signal is taken off from each sensor strip 5 ′. In the limiting case the signals act as spot strain gauges.
In FIG. 4 c, the same sensor strips 5 ′ are connected to a common bus connector 5 a that provides for individual take-off points for each sensor strip.
By the above means a multichannel electrical signal is derived, the channels of which reflect the localised displacement of the patient's body in the vicinity of each of the sensor strips 5 , as indicated in FIG. 5 . By this means the movement of the body during, for example, respiration may be monitored. This, therefore, provides a means of imaging the displacements of the torso, particularly with regard to respiration, in a reclining patient. By virtue of its many sensor strips, the system is largely insensitive to patient orientation on the movement-sensitive mattress 2 .
Different respiratory states of the patient produce different patterns of the aforementioned displacements. FIG. 6 illustrates typical patterns during normal respiration while FIG. 7 illustrates typical patterns associated with disordered breathing.
Referring to FIG. 8 a, the sensor strips 5 are constructed of a layer of polyvinyledene fluoride (PVDF) film 11 , a supporting mylar film 13 , an adhesive layer 8 to join together the said films and an adhesive layer 41 to adhere the resulting assembly to the inside surface of the neoprene envelope 6 , as shown in FIG. 3 .
The PVDF film 11 has the property whereby an electrical charge is generated across the faces of the film 11 when a mechanical strain is applied along the length of the film 11 The electrical charge is conducted from the surface of the layer PVDF film 11 by two conductive, metallised surface layers, a first layer 10 and the second layer 12 which are affixed to opposing faces of the film 11 during its manufacture.
The mylar film 13 acts as a physical support for the PVDF film 11 and regulates the amount of strain applied to the said film when the sensor strip 5 is stretched. The mylar film 13 also has applied on one face a conductive, metallised surface layer 14 which is used to screen the second conductive layer 12 of the PVDF film 11 from external electrical interference. The first conductive layer 10 of the said PVDF film 11 is externally connected to the metallised layer 14 of the mylar film 13 so that the second conductive layer 12 of PVDF film 11 is effectively screened on both sides from electrical interference.
Typical dimensions of each sensor strip 5 are 650 mm long by 12 mm wide. The PVDF film is typically 28 μm in thickness and the mylar film 13 typically 1 mil in thickness. The sensor strip 5 can, for example, be made up from the above-mentioned films by the AMP Corporation of PO Box 799, Valley Forge, Pa. 19482, USA, as a modification of their standard range of piezoelectric film products.
Referring to FIGS. 9 a and 9 b, electrical charge generated by each of the sensor strips 5 is conducted from the sensor strip 5 by a sensor strip connection means 42 . The connection means 42 makes connections to the first conductive layer 10 and second conductive layer 12 of the PVDF film 11 and the metallised layer 14 of the mylar film 13 , and, further, electrically connects first conductive layer 10 and metallised layer 14 together for electrical screening purposes. The resultant two electrical paths are connected to a coaxial cable 33 for transmission to interface means 103 .
As shown in FIG. 8 a, the various layers at one end of the sensor strip 5 are staggered in such a way as to provide conductive areas 15 and 16 which will be described below. Sensor strip connection means 42 (see FIG. 9 a ) comprises a double sided printed circuit board 18 with a contact area 19 that makes electrical contact via conductive adhesive with a conductive area 15 (see FIG. 8 a ) of the metallised layer 14 of the mylar film 13 ; a contact area 20 that makes electrical contact with a conductive area 16 of the second conductive layer 12 of the PVDF film 11 ; and a contact area 21 that makes electrical contact with the first conductive layer 10 of the PVDF film 11 by means of a conducting bridge 30 described below. Most of the surface 18 a of the printed circuit board 18 adjacent to the aforesaid electrical contacts to sensor strip 5 is unetched, that is, it remains as conductive copper. This allows the electrical connection between the metallised layer 14 of the mylar film 13 and the first conductive layer 10 of the PVDF film 11 , both of which are subsequently grounded. Contact area 20 is electrically isolated from said conductive copper by an etched insulating area 22 . This allows contact with the ungrounded second conductive layer 12 of the PVDF film 11 .
The electrical signal from the conductive area 16 of second conductive face 12 of PVDF film 11 , connected to sensor strip connection means 42 via contact area 20 is conducted from the said contact area to connecting pad 23 via copper track 24 located on the reverse side of printed circuit board 18 .
As shown in FIG. 9 b, the electrical signal from first conductive layer 10 of PVDF film 11 is connected to the conducting copper top face of contact area 21 of printed circuit board 18 by a conducting bridge 30 constructed from copper tape with conductive adhesive on its contact side. The electrical signal from the conducting copper top face of printed circuit board 18 is conducted to a connecting pad 25 on the printed circuit board 18 .
As shown in FIG. 10 b, conducting bridge 30 and the two other aforementioned sensor strip connections are maintained in a state of intimate connection with their respective contact areas 19 , 20 , 21 by a non-conducting, rigid pressure plate 31 which bears down on the aforementioned contact assemblies by virtue of two pressure springs 32 .
Referring to FIG. 11 a, to a connecting pad 23 on the printed circuit board 18 is soldered or otherwise electrically attached the inner conductor 35 of a coaxial cable 33 . To connecting pad 25 is soldered or otherwise electrically attached the outer screening conductor 34 of the coaxial cable 33 .
The coaxial cable 33 is attached to circuit board 18 by a method which simultaneously stress relieves the soldered connections and locates the cable 33 . The coaxial cable 33 is located over cable location tongue 27 (as illustrated in FIGS. 11 a & 11 b ), sourced from circuit board 18 by two parallel slots 28 . This arrangement allows a heatshrink sleeve 36 to be pushed simultaneously over the coaxial cable 33 and the cable location tongue 27 so that, on the application of heat, the reduction in diameter of the heatshrink sleeve 36 pulls the coaxial cable 33 into intimate and stable contact with the cable location tongue 27 . Adhesive on the interior of the heatshrink sleeve 36 plus its physical grip when shrunk ensure that the coaxial cable 33 is clamped sufficiently for there to be no strain on its internal conductors 34 and 35 .
Referring to FIGS. 12 a and 12 b, the circuit board 18 is attached to the interior of the neoprene envelope 6 using a novel arrangement of adhesive that reduces the strain on the electrical connections between the sensor strip 5 and the circuit board 18 . The sensor strip 5 is attached to the circuit board 18 using adhesive in location 40 ; adhesive barrier slot 29 is cut in the circuit board to prevent adhesive from location 40 straying into contact area 19 . Adhesives in the location 40 and subsequently described are all of a high strength cyano-acrylic gel type such as that sold under the registered trademark “LOCITE 454”. The sensor strip 5 is attached to the neoprene envelope 6 along its length by an adhesive strip 41 , for example the transfer adhesive sold under the registered trademark “3M TYPE 9460”.
The circuit board 18 is constructed with two strain relief horns 26 which are attached to the interior surface of the neoprene envelope 6 using the above-mentioned cyano-acrylic adhesive applied at locations 37 . The function of the strain relief horns 26 is to limit the stretch of the neoprene envelope 6 in the vicinity of the attachment of the circuit board 18 to the sensor strip 5 thus significantly reducing the strain on the aforementioned electrical connections with the strip 5 . Optionally, the sensor strip 5 can additionally be stabilised by the application of the said cyanoacrylic adhesive at location 39 . The remainder of circuit board 18 is attached to the neoprene envelope 6 using said cyano-acrylic adhesive in at least locations 38 .
Referring to FIG. 13, an alternative embodiment 93 combines circuit boards 18 in parallel on to one long bus board 94 or circuit strip such that the individual connections to strips 5 are conducted in parallel to a single multichannel connector 95 to which is connected a single multicore cable 96 which conducts all the signals from sensor strips 5 . Optionally, sensor buffers 43 described below may be located in close proximity to the bus board 94 .
Referring to FIGS. 14 a to 14 d, electrical signals from each sensor strip connection means 42 are conducted to a respective sensor buffer 43 via the coaxial cable 33 (not shown in FIGS. 14 a to 14 b ). The sensor buffer 43 can be of the form where an operational amplifier 51 operates as a charge amplifier (as shown in FIG. 14 a ). balancing charge received from sensor strip 5 in response to the patient's movement, against charge built up on a capacitor 52 from operational amplifier output 54 . This design is commonly used in such situations and referenced in “Piezo Film Sensors Technical Manual O/N: 6571” published by the AMP Corporation of PO Box 799, Valley Forge, Pa. 19482, USA. This Technical Manual also indicates the necessity of using silicon diodes 55 (as shown in FIG. 14 b ) to protect the input of the operational amplifier 51 against high voltage transients produced if sensor strip 5 is subjected to a large impulsive force. The action of the diodes 55 is to clamp the input voltage of the operational amplifier 51 to approximately the operational amplifier supply voltages, +V and −V as indicated in the FIG. 14 b.
The use of the protection diodes 55 in the above-mentioned configuration does however have a drawback, namely the reverse leakage current of the diodes 55 flows into the virtual earth 46 of the operational amplifier 51 which results in a compensating offset voltage at the output 54 of the operational amplifier 51 .
Two solutions to this problem are presented, and shown in FIGS. 14 c and 14 d respectively. The input 47 of the sensor strip 5 to the operational amplifier 51 in the above-mentioned charge amplifier configuration is a virtual earth 46 , that is the negative feedback of the operational amplifier 51 acts to maintain the voltage at the input 47 at zero. In practice the input voltage at input 47 may be a small number of millivolts because of constructional imperfections within the operational amplifier 51 . Notwithstanding this latter voltage, the input impedance of such a virtual earth is very low (because the operational amplifier acts to drain away charge in order to maintain the virtual earth)—some tens of ohms at the most, therefore an external impedance can be placed between the virtual earth point 46 and ground 99 and, providing said impedance is larger than about 1000 ohms, that is, large relative to the virtual earth impedance, the functioning of the charge amplifier is unaffected. This allows a combination of parallel 56 and serial 57 impedances to replace the above-mentioned reverse biased diodes 55 connecting the virtual earth 46 to the above-mentioned operational amplifier supply rails (±V). Whereas the voltage on the sensor strip 5 produced by the accumulation of charge due to a large impulsive force applied thereto may be large—of the order of 100 volts—the effective source impedance of the sensor strip 5 is also very large—up to 10 12 ohms. Hence the addition of even a fairly large impedance (by electronic standards) of 1 Mohm across the sensor strip 5 dramatically reduces the open circuit voltage that can occur across the strip 5 . As an additional precaution, a small series resistor 57 can be placed in series with the output of the sensor strip 5 to limit any residual current flow into the operational amplifier 51 input under overload conditions. During non-overload operation these components are effectively invisible to the charge amplifier function—parallel resistor 56 is much greater than the input impedance of the above-mentioned virtual earth and series resistor 57 , which is typically 1 kohm, is effectively zero compared with the 10 12 ohms source impedance of the sensor strip 5 . One additional advantage of this configuration is that parallel resistor 56 supplies bias current to the operational amplifier 47 input, thus relieving DC feedback stabilisation resistor 53 of any magnitude constraints (in the above-mentioned conventional charge amplifier, feedback resistor 53 is limited in magnitude because increasing its value increases the output offset voltage of the amplifier).
As an alternative to the above embodiment of FIG. 14 c, silicon diodes 46 can be used back to back between the virtual earth 46 and ground 99 (as shown in FIG. 14 d ). Under non-overload conditions the voltage across the diodes 46 is insufficient for them to conduct, hence they are invisible to the charge amplifier circuit. Under overload conditions one of the diodes 46 will conduct if the voltage increases above about 0.5 volts, thus limiting the overload voltage applied to the input 47 of operational amplifier 51 . Optionally, a parallel resistor 47 a of about 1 Mohm can be placed in parallel with the diodes 46 to provide bias current for the operational amplifier inputs, thereby relieving the above-mentioned magnitude constraint on DC feedback resistor 53 .
DC feedback stabilisation resistor 53 in conjunction with feedback capacitor 52 forms a highpass filter with an effective—3 dB frequency of approximately 0.1 Hz. Signal components below this value, being largely due to thermoelectric and slow semiconductor drift effects are, therefore, attenuated. This technique is referenced in the aforementioned “Piezo Film Sensors Technical Manual O/N: 6571”
The outputs 54 of the charge amplifiers 43 are then passed through a further gain stage 44 (see FIG. 15) which comprises a low pass filter with a −3 dB frequency point of approximately 100 Hz.
Referring to FIG. 15, the outputs of gain stages 44 are input to a multichannel Analog to Digital Converter (ADC) 45 which has at least as many inputs as there are sensor strips 5 . The ADC converter 45 transforms each of the inputs to a numerical digital signal 58 for subsequent processing and storage with a precision of at least 12 bits at a rate of approximately 200 samples per second.
The digital output signals 58 of the ADC 45 are input to computing means 104 which processes the inputs and which stores the digital outputs to computer disk 107 for subsequent retrieval.
Optionally one or more external electrical inputs 48 , 49 are provided to permit the recording and subsequent processing of signals derived from the movement-sensitive mattress 2 . Such signals are, typically, the output from an oximeter (not shown) attached to the finger or ear of the patient, and the output from a pressure transducer (not shown) connected to a mask on the patient's face or nasal prongs inserted in the patient's nares in order to detect respiration.
External electrical inputs 48 , 49 are connected to combination buffer amplifiers and low pass filters 50 the outputs of which are connected to the inputs of the ADC 45 in parallel with the above-mentioned sensor strip gain stages 44 for similar conversion to digital outputs 45 but at sampling rates typically lower, say at 50 Hz.
Referring to FIG. 16, digitised signals 58 resulting from movements of the sensor strips 5 in the movement-sensitive mattress 2 are input to pre-processing means 59 (forming part of the computing means 104 ) to produce pre-processed digitised signals 60 . The pre-processing means 59 acts both temporally on each individual channel of the digitised signals and spatially on two or more of the digitised signals in concert.
The pre-processing means 59 acts on each channel of digitised signals 58 firstly to equalise the gains of each channel, that is, to remove the variation in amplitude and phase response of each sensor strip 5 relative to the other sensor strips 5 , and secondly and optionally to deconvolve the signal of each sensor strip 5 from the effects of adjacent strips 5 (as shown in FIG. 17 ). Thus processed, the signals are output as pre-processed digitised signals 60 .
The above-mentioned deconvolution comprises the subtraction from at least each adjacent channel 63 adjacent to the channel 62 being deconvolved, of a precalculated fraction of the signal measured in said channel 62 such as to remove from said adjacent channels 63 any signal contribution due to physical pressure 61 exerted on the sensor strip 5 corresponding to the channel 62 being deconvolved. The effect of this procedure is to localise or “sharpen” the spatial response for each channel.
Basic Processing
Referring to FIG. 18 a, the pre-processed digitised signals 60 are then separately input in parallel to a number of basic processing means 64 , 66 , 68 , 70 , 72 , 74 , 76 , 78 , 80 , 82 , 97 and 134 (again forming part of computing means 104 ) whose function is to extract particular features from the digitised signals, the features subsequently being used in combination to obtain a diagnosis. Some of said basic processing means act temporally on each individual channel of the said digitised signals while others act spatially in concert on two or more of the said pre-processed digitised signals.
Respiratory Effort
Basic processing means 64 acts on one or more of pre-processed digitised signals 60 to produce a basic derived signal 65 which is a measure of the sum total of the patient's movement, regardless of polarity. The basic derived signal 65 is a measure of the patient's instantaneous respiratory effort ER and is calculated as:
Respiratory effort E R ( t ) = ∑ i = 1 N mod s i ( t )
where N is the number of sensor strips 5 , and s i (t) is the signal derived from the ith sensor strip 5 as a function of time. S i therefore corresponds to the displacement of the ith sensor strip 5 .
An alternative calculation is: E R ( t ) = ∑ i = 1 N s i 2 ( t )
Basic processing means 66 acts on one or more of pre-processed digitised signals 60 to produce a basic derived signal 67 which is a measure of the integral over a complete breath, or the summed separate integrals over the inspiratory and the expiratory phases, of the sum total of the patient's movement, regardless of polarity. The basic derived signal 67 is a measure of the patient's total respiratory effort T R for the breath and is calculated as:
Total respiratory effort T R = ∫ breath ∑ i = 1 N mod s i ( t ) · t
where N is again the number of sensor strips, and mod s i (t) is the modulus (amplitude) of the signal derived from the ith sensor strip 5 as a function of time.
An alternative calculation is T R = ∫ breath ∑ i = 1 N s i 2 ( t ) · t
Respiratory Phase
Basic processing means 68 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 69 which is a measure of the respiratory phase of the patient. The basic derived signal 69 indicates at what point in the inspiration/expiration cycle the pre-processed digitised signals 60 are being measured and may be calculated in one instance by fitting retrospectively in time a sine wave, as a function of time, to the largest in amplitude of pre-processed digitised signals 60 . The basic derived signal 69 associated with specific pre-processed digitised signals 60 is then calculated as the phase angle at whichever point on the aforementioned sine wave coincides temporally with the measurement point reached in said pre-processed digitised signals.
Basic processing means 70 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 71 which is a measure of the spatial respiratory zero phase point of the patient. The basic derived signal 71 indicates at what position on the movement-sensitive mattress 2 the patient's body changes from exerting positive to negative pressure and changes significantly with the patient's mode of breathing. The signal is calculated as the sensor strip 5 index (n) at which the sums of the positive and negative displacements are equal within a prescribed error, namely:
n is “zero phase point”
when ∑ i = 1 N - n s i ( t ) ≈ 0 - ∑ i = n N s i ( t )
Corporeal Displacement
Basic processing means 72 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 73 which is a measure of the average displacement (P R ) of the patient. The basic derived signal 73 indicates the degree that the thorax and abdomen of the patient are free to move independently of each other and is thus sensitive to the transition from unobstructed to obstructed, that is, so called paradoxical, breathing efforts.
Such a signal may be calculated as: P R ( t ) = ∑ i = 1 N s i ( t )
and/or
by observing a change of phase or sign between channels which have been moving in phase for some time (typically some number of minutes)
and/or
a diminution of observed movement in the sensor strips 5 in contact with the abdominal area of the body (rather than the thoracic).
Snore
Basic processing means 74 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 75 which is a measure of the snore amplitude of the patient. A signal indicative of snore amplitude may be calculated by passing each channel of the aforesaid pre-processed digitised signals through a digital high pass filter with a low frequency cut-off of approximately 10 Hz, then calculating the modulus of each resulting signal, then summing all the moduli and passing the sum through a low pass filter with a high frequency cut-off of between 0.5 and 2 Hz. Basic derived signal 75 is the resultant output of the aforesaid low pass filter.
Basic processing means 76 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 77 which is a measure of the harmonic purity of the patient's snore, that is, its closeness in form to a simple sine wave. The basic derived signal 77 varies with the type of snore—a non-obstructive snore having a different degree of harmonic purity than an obstructive one. A signal indicative of such above-mentioned snore harmonic purity may be calculated by passing each channel of the aforesaid pre-processed digitised signals 60 through a digital high pass filter with a low frequency cut off of approximately 10 Hz, then selecting the channel with the highest resulting highest amplitude and calculating the instantaneous phase of the signal by, for example, deriving the “analytic” signal from the input signal by passing it through a 90 deg phase shift filter, then differentiating the instantaneous phase, then low pass filtering the resultant differential and differentiating again. Basic derived signal 77 is the resultant output, being inversely proportional to the purity of the snore harmonic content.
Basic processing means 78 yet further acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 79 which is a measure of the harmonic stability of the patient's snore, that is, the accuracy with which one cycle of the snore signal matches its predecessor. The basic derived signal 79 varies with the type of snore—a non-obstructive snore having a different degree of harmonic stability than an obstructive one. A signal indicative of such above-mentioned snore harmonic stability, may be calculated by passing each channel of the aforesaid pre-processed digitised signals 60 through a digital high pass filter with a low frequency cut off of approximately 10 Hz, then selecting channel with the highest resulting highest amplitude and autocorrellating the signal. The number of autocorrellation peaks, normalised for frequency, greater than a preset value, nominally 0.8, present in a rolling window of a preset time, nominally 0.2 seconds, gives basic derived signal 79 , being proportional to the stability of the snore harmonic content.
Non-respiratory Movement
The basic processing means 80 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 81 which is a measure of non-respiratory movements of the patient. The basic derived signal 81 may be calculated by passing each channel of the pre-processed digitised signals 60 through a digital band pass filter with a pass band of approximately 10 to 40 Hz, then calculating the modulus of each resulting signal, then summing all the moduli and passing the sum through a low pass filter with a high frequency cut off of between 2 and 10 Hz. Basic derived signal 79 is the resultant output of the aforesaid low pass filter.
Heartrate
Basic processing means 82 also acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 83 which is a measure of the heartrate of the patient. The basic derived signal 83 may be calculated by passing each channel of the aforesaid pre-processed digitised signals through a digital band pass filter with a pass band of approximately 5-15 Hz, then selecting the channel with the highest resulting highest amplitude and detecting the ballistocardiogram impulse associated with each heartbeat using a matched filter or similar technique. The resultant time interval between matched filter correlation outputs greater than a preset value, nominally 0.8, gives basic derived signal 83 . Optionally, to compensate for missed beats, the aforementioned time interval can be divided by two to give a value within the bounds of physiologic possibility.
Alternatively, the abovementioned bandpassed signals may be correlated against past time sets of the same signals in an identical way to that used to determine respiration rate (as described below), to determine basic derived signal 83 , the heartrate.
The basic processing means 134 acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 135 which is a measure of the amplitude of the cardioballistogram of the patient. The basic derived signal 135 may be calculated as the unnormalised output of the matched filter correlation technique used to calculate basic derived signal 83 , measured at a time coincident with the maximum of basic derived signal 83 .
Spatial Effort Point
Basic processing means 97 yet further acts on one or more of pre-processed digitised signals 60 to produce basic derived signal 98 which is the spatial respiratory maximum effort point of the patient. The signal is calculated as the sensor strip 5 index at which the integral over a complete breath of the sum total of the patient's movement, regardless of polarity, is a maximum. First, the integral of the movement of each sensor strip 5 is calculated separately as: R i = ∫ breath mod s i · t for i = 1 to N
where N is the number of sensor strips, and mod s i (t) is the modulus (amplitude) of the signal derived from the ith sensor strip 5 as a function of time.
An alternative calculation is R i = ∫ breath mod s i 2 · t for i = 1 to N
The value of the spatial respiratory maximum effort point is the value of i for which R i as calculated above is a maximum.
Respiratory Rate
A further basic processing means (not shown) can act on pre-processed digitised signals 60 to produce a further basic derived signal (not shown) which is a measure of the prevailing respiratory rate. This basic derived signal is calculated by correlating the spatial “shape” of the sensor pattern at any given time with the “shapes” of the sensor pattern in past time; the first occurrence of a good correlation (with a coefficient greater than a preset value, typically 0.9) indicates at what time previously a similar pattern occurred, that is, the current respiration rate.
First each channel of the aforesaid preprocessed digitised signals 60 is passed through a low pass digital filter with a high frequency cutoff of approximately 2 Hz and, optionally, the sampling rate of the said filtered signals is decimated down to approximately 20 Hz for subsequent computing convenience. At each sampling point in time, the current spatial set of filtered sensor signals, ∑ i = n N S n ( t )
is cross correlated against the sets sampled at previous times to give a correlation function: C ( t - m T ) = ∑ i = n N S n ( t ) · ∑ i = n N S n ( t - m T )
the maxium value of m for which correlation function C exceeds the aforementioned threshold is the period separating the present from previous, similar phases of breathing, that is, the breath to breath interval. This measurement is performed at each sampling period, generating many estimates of respiration rate per breath. The individual estimates of the maximum value of, m, can optionally be low passed filtered to diminish the effect of transient signal artefacts.
Further basic processing functions can be performed as follows.
‘Laboured’ Breathing
Many patients with respiratory problems exhibit “laboured” breathing as a symptom of their condition. By “laboured” breathing is meant a physical exertion, associated with inspiration or expiration, that is significantly greater than the normal exertions of breathing. In one patient subgroup, such laboured breathing is caused by an increase in upper airway resistance, particularly on inspiration.
It is known that patients whose upper airways are partially obstructed produce electrical signals in the Static Sensitive Charged Bed that have a higher frequency component—so called “high frequency spiking” (Polo O, “PhD Thesis”, republished as a supplement in Acta Physiologica Scandinavica Vol 145, Supplementum 606, 1992). In the prior art, processing of the aforementioned higher frequency component has been limited to bandpass filtering prior to display as a time varying trace on an oscilloscope or polygraph. In viewing such a display, the trained observer can estimate by eye that a degree of laboured breathing exists but cannot quantify it or diagnose its extent automatically because the magnitude of the signal varies with such parameters as the orientation of the subject with reference to the sensor, his or her size and shape.
One or more of the electrical signals 44 from the movement sensitive bed sensor strips 5 or preprocessed signals 60 are passed through an analog or digital Effort Filter with a passband that rejects both the low frequency signals, predominantly produced by basic respiration, and the high frequency signals produced by snoring and cardiac action. Typically the pass band of the said Effort Filter is from 4 Hz to 10 Hz and after the filter the modulus of the signal is taken and the resulting signal low pass filtered at about 4 Hz to give a signal proportional to the amplitude of the original bandpassed one. The output of the Effort Filter is then subjected to two, parallel processes—firstly the said output is averaged over the entire duration of each respiratory phase, that is, separately over the inspiratory phase and the expiratory phase, and secondly, the maximum amplitude reached by the said output within each respiratory phase is measured and stored. These measurements are termed, respectively, the Average Respiratory Phase Effort and the Maximum Respiratory Phase Effort. The said Effort measurements can be displayed and stored in their own right or, preferably used as inputs to further processing described below.
A significant improvement is offered over existing systems in that there is provided a method of measuring the extent of laboured breathing and determining objectively the degree thereof. Such an embodiment of the invention is amenable to use within automatic respiratory diagnostic systems.
Respiratory Phase Change
In the automatic assessment of respiratory performance it is advantageous to determine the onset of each of the two respiratory phases, inspiration and expiration. This embodiment consists of the further processing of the cross correlation signal used to determine the respiratory rate. The aforesaid signal is the output of a process that correlates the set of sampled signals from the sensor strips 5 with previous sets of the same signals, stored back in time. For regular breathing, there will be a point in time, one breath back, where the values of the sampled set of sensor signals will be almost identical to the current set. This is evident in the output of the amplitude normalised cross correlation described in the original provisional patent. FIG. 18 b shows the outputs of the said cross correlation with increasing time into the past. In FIG. 18 b expiration or inspiration has just started and correlation between the current signal set and its immediate predecessors quickly declines. One breath back, correlation again increases towards +1.0, enabling the current respiration rate to be measured as time, T 1 , between correlation threshold levels TH 1 .
The system monitors the value of the above past time cross correlation signal with time. As time into the inspiration or expiration progresses, the values of each time sampled set of strip signals stabilises, giving an increased span of correlation with the immediate past signals. This is observable in FIGS. 18 b-d, where the time into the past, T 2 , for the cross correlation signal to fall from a good correlation of almost +1.0 to the negligible correlation threshold, TH 2 , increases with time. At the end of the respiratory phase, significant past correlation time, T 2 , is at a maximum (FIG. 18 d ; at the onset of the next respiratory phase, that is the transition between inspiration and expiration or vice versa, the extent of past time correlation and hence the value of T 2 drops significantly to the start of phase pattern indicated in FIG. 18 b. The aforementioned reduction in the significant past correlation time is indicative of a change of respiratory phase. The processing system monitors the value of the said past correlation time and compare it continuously with a threshold value of typically 70% of the maximum reached. When the value of the said time drops below that of the said threshold the end of inspiration or expiration is indicated.
Respiratory Rate I
The system determines the elapsed time between the last two indications of respiratory phase change of method immediately above. This elapsed time is the current breath time, effectively measured at every half breath interval.
Detection of Abnormal Breathing
Respiration with a relatively unobstructed airway gives rise to a past time correlation pattern described above and indicated in FIG. 18 e. A particular characteristic of this correlation pattern is that the correlation values throughout the respiratory cycle tend to be close to either +1.0 (correlation) or −1.0 (anti-correllation), remaining at intermediate values for only a small percentage of the time.
This characteristic is used to distinguish between relatively unrestricted respiration and highly restricted or totally obstructed, so-called paradoxical respiration, in which there can be a significantly more gradual decline in past time away from correlation, and, in which the correlation value no longer approaches the anti-correlation level of −1.0 (FIG. 18 f ). Specifically, the present invention takes the past time correlation values as shown in FIGS. 18 f and 18 g and performs two processes in parallel. Firstly, the said values are averaged over the period from the present back in time to the point prior to the last complete breath that the said values fall to a level of insignificant correlation, typically zero; this is indicated by time, T, in FIGS. 18 e and 18 f . Secondly, the arithmetic modulus of the said values is subjected to averaging over the same, aforementioned period. Alternatively, the abovementioned averaging period can cover the time between the first fall in past time of the correlation value below the threshold of significance and the similar fall for one breath into the past (not indicated). The abovementioned averages are termed, respectively, the Past Breath Correlation Mean and the Past Breath Correlation Modulus Mean.
The Past Breath Correlation Mean is then compared with a threshold close to zero, typically, 0.25. If the said Mean exceeds the said threshold then the breath is deemed to be abnormal, that is, the inspirational correlation profile does not match in antiphase that of the expiration.
Alternatively or additionally, the Past Breath Modulus Mean is compared with a threshold close to 1.0, typically 0.8. If the said Sum exceeds the said threshold then the breath is deemed to be normal, that is, the correlations during inspiration are antiphase to those during expiration.
Diagnostic Processing
Basic derived signals 65 , 67 , 69 , 71 , 73 , 75 , 77 , 79 , 81 , 83 , 98 & 135 plus the abovementioned respiratory rate, laboured breathing, respiratory phase change, alternate respiratory rate and detection of abnormal breathing signals are, in turn, input to diagnostic processing means 84 (forming part of computing means 104 ) which acts on one or more of the said basic derived signals to produce diagnostic signals 85 through 92 .
Occurrence of Obstructive Apnea
Diagnostic signal 85 is indicative of the occurrence of an obstructive apnea.
This may be determined from the following states of the above-mentioned basic derived signals:
1. reduction in basic derived signal 73 ( respiratory displacement P R ( t ) = ∑ i = 1 N s i ( t ) )
compared with 5 minute moving average of basic derived signal 73 (respiratory displacement),
plus
2. increase in basic derived signal 65 ( respiratory effort E R ( t ) = ∑ i = 1 N mod s i ( t ) )
compared with 5 minute moving average of basic derived signal 65 (respiratory effort),
plus
3. near zero value of basic derived signal 75 (snore amplitude),
immediately followed by
4. sudden increase in basic derived signal 81 (non-respiratory movements)
optionally plus
5. the aforesaid state (i.e. coincidence of states 1 , 2 and 3 above) may be preceded by an increase in basic derived signal 75 (snore amplitude)
optionally plus
6. a marked reduction in arterial oxygen saturation as indicated by an external oximeter connected to external electrical input 48 .
Obstructive Apnea Duration
Diagnostic signal 86 is indicative of the duration in time of the above-mentioned obstructive apnea. This is calculated only if diagnostic signal 85 indicates the occurrence of an obstructive apnea and typically may be determined from the length of time of the coincidence of a reduction in basic derived signal 73 (respiratory displacement) compared with 5 minute moving average of basic derived signal 73 (respiratory displacement), an increase in basic derived signal 65 (respiratory effort) compared with 5 minute moving average of basic derived signal 65 (respiratory effort) and a near zero value of basic derived signal 75 (snore amplitude). Optionally the aforesaid state (i.e. coincidence of states 1 , 2 and 3 above) may be accompanied by a marked change in basic derived signal 135 (ballistocardiogram amplitude). Optionally the aforesaid state (i.e. coincidence of states 1 , 2 and 3 above) may be accompanied by a marked decrease in basic derived signal 83 (heartrate), followed by a marked increase therein.
Diagnostic Signal Accuracy
Diagnostic signal 87 is indicative of the expected accuracy of the above-mentioned diagnostic signal 85 (obstructive apnea occurrence). This is calculated only if diagnostic signal 85 indicates the occurrence of a said obstructive apnea and typically may be determined from the following states of the above-mentioned basic derived signals:
a marked increase in the ratio of basic derived signal 65 (respiratory effort) with respect to basic derived signal 73 (respiratory displacement),
plus
a low level during the preceding minute of basic derived signal 81 (non-respiratory movements)
plus, optionally
a marked shift of basic derived signal 71 (zero phase point) during the apparent obstructive apnea
plus, optionally
a marked shift of basic derived signal 98 (spatial respiratory maximum effort point) during the apparent said obstructive apnea.
Occurrence of Central Apnea
Diagnostic signal 88 is indicative of the occurrence of a central apnea. This may be determined from the following states of the above-mentioned basic derived signals:
reduction towards zero in basic derived signal 73 (respiratory displacement) compared with 5 minute moving average of basic derived signal 73 (respiratory displacement),
plus
reduction towards zero in basic derived signal 65 (respiratory effort) compared with 5 minute moving average of basic derived signal 65 (respiratory effort),
plus
near zero value of basic derived signal 75 (snore amplitude),
followed after a variable period by
increase in basic derived signal 73 (respiratory displacement) compared with 1 minute moving average of basic derived signal 73 (respiratory displacement),
plus
increase in basic derived signal 65 (respiratory effort) compared with 1 minute moving average of basic derived signal 65 (respiratory effort),
or, optionally, immediately followed by
a sudden increase in basic derived signal 81 (non-respiratory movements).
Central Apnea Duration
Diagnostic signal 89 is indicative of the duration in time of the above-mentioned central apnea. This is calculated only if diagnostic signal 88 indicates the occurrence of a central apnea and may be determined from the length of time of the coincidence of a reduction in basic derived signal 73 (respiratory displacement) compared with 5 minute moving average of basic derived signal 73 (respiratory displacement), a reduction in basic derived signal 65 (respiratory effort) compared with 5 minute moving average of basic derived signal 65 (respiratory effort) and a near zero value of basic derived signal 75 (snore amplitude).
Diagnostic Signal Accuracy
Diagnostic signal 90 is indicative of the expected accuracy of the above-mentioned diagnostic signal 88 (central apnea occurrence). This is calculated only if diagnostic signal 88 indicates the occurrence of a central apnea and may be determined from the following states of the above-mentioned basic derived signals:
no marked increase in the ratio of basic derived signal 65 (respiratory effort) with respect to basic derived signal 73 (respiratory displacement),
plus
a low level during the preceding minute of basic derived signal 81 (non-respiratory movements)
plus
no marked shift of basic derived signal 71 (zero phase point) during the apparent said central apnea.
The above-mentioned diagnostic signals 85 (obstructive apnea indication) and 88 (central apnea indication) may be expressed simultaneously in the case of a mixed apnea, that is, a combination of both types of apnea.
Occurrence of Sudden Body Movement
Diagnostic signal 91 is indicative of the occurrence of a sudden body movement without a preceding apnea. Typically this would be determined from the following states of the above-mentioned basic derived signals and the above-mentioned diagnostic signals:
the absence of diagnostic signal 85 (obstructive apnea occurrence)
plus
the absence of diagnostic signal 88 (central apnea occurrence)
plus
a sudden increase in basic derived signal 81 (non-respiratory movements).
Degree of Obstructive Breathing
Diagnostic signal 92 is indicative of the degree of obstructive breathing present. Typically this may be calculated from the following states of the above-mentioned basic derived signals:
the ratio of basic derived signal 65 (respiratory effort) to basic derived signal 73 (respiratory displacement) averaged over a 1 minute period
or
the ratio of basic derived signal 65 (respiratory effort) to basic derived signal 73 (respiratory displacement) averaged over the previous breath
plus, optionally
the value of basic derived signal 75 (snore amplitude),
plus, optionally
the inverse value of basic derived signal 77 (snore harmonic purity)
Diagnostic signals 85 through 92 are subsequently:
a) stored to computer disk 107 , and/or
b) output graphically to display means 106 in one of several forms, for example as a condensed report of the night's study (as shown in FIG. 19 ), and/or
c) output in alphanumeric coded form to physiologic channel output means 110 for subsequent recording and display in association with other electrophysiological signals through a polygraph as described below.
Further diagnostic processing functions can be performed as follows.
Estimation of Degree of Laboured Breathing
An objective measure of laboured breathing can be derived from two of the abovementioned basic processing means. The aforementioned Average Respiratory Phase Effort and Maximum Respiratory Phase Effort signals are processed using the aforementioned indications of respiratory phase change which delineate the temporal boundaries of inspiration and expiration, to derive two signals, respectively the Average Effort Ratio and the Maximum Effort Ratio.
The Average Effort Ratio is determined by dividing the Average Respiratory Phase Effort for the respiratory phase just ended by that determined for the previous phase. Similarly, the Maximum Effort Ratio is determined by dividing the values of Maximum Respiratory Phase Effort for successive phases. For non-laboured breathing, the values of the Average Respiratory Phase Effort and Maximum Respiratory Phase Effort for inspiration and expiration are approximately equal for inspiration and expiration, giving Effort Ratios of approximately unity. If, however, the execution of one phase of respiration, for example inspiration, becomes significantly laboured relative to the other phase, then the Effort Ratios will move away from unity by a factor of two or more. Thus, when deviations of the Effort Ratios for successive respiratory phases drop below typically 0.5 or exceed typically 2 then abnormal effort is indicated and the breath can be defined as “laboured”. Two features of the invention are that, firstly, the use of the ratio eliminates the need for scaling the measured signals or knowing details of the subject's orientation and, secondly, knowledge is not required of whether a particular phase is inspiration or expiration. Furthermore, a comparison between the two ratios themselves can give an indication of whether the effort occurs impulsively at the start of the respiratory phase, or in a more diffuse manner throughout the phase: similar values indicate a diffuse effort, a higher Maximum Effort Ratio indicates an initial, impulsive effort.
Estimation of Degree of Snoring
Separately the procedures used to quantify ‘laboured’ breathing described above may be applied to determine the amount of snoring present, in which case the bandpass frequencies of the effort filters described above are approximately 10 Hz and 100 Hz. The ratios so determined are termed the Average Snore Ratio and the Maximum Snore Ratio.
Classification of respiratory phase—Past Time Correlation Curve Shape
The difference in the speed at which a subject changes from inspiration to expiration is compared with vice versa to indicate which of these changes has occurred. The time taken for the past time correlation value to fall from an Upper Threshold (not shown) to a Lower Threshold (not shown) for the most recent fall of the said correlation (edge ‘A’ in FIG. 18 b ) is compared to the time taken for the previous transition in correlation between the same thresholds (Curve ‘B’ in FIG. 18 b ). if the latter transition is slower then the current phase is inspiration, if faster, expiration.
Classification of respiratory phase—Use of Effort Ratios
Particular subgroups of respiratory ailments are characterised by the occurrence of laboured breathing in a particular phase of respiration. Thus, for example, sufferers from Obstructive Sleep Apnea and most other upper respiratory tract disfunctions will work harder on inspiration than expiration. The system compares the Average Effort Ratio and/or the Maximum Effort Ratios with threshold values typically of 1.2 and 0.8. If the Ratios exceed the upper threshold then the last phase was an inspiration, if it is less than the lower threshold, then an expiration. Alternatively or additionally, the abovementioned Average Snore Ratio and Maximum Snore Ratios may also be used to classify the respiratory phase.
Classification of respiratory phase—Use of Mean Strip Value
The system makes use of the fact that in most patient groups inspiration and attempted inspiration is associated with expansion of the thorax, by processing the signals from a selected range of sensor strips from the top location (normally adjacent to the patient's neck or scapulae) down to the approximate level of the patient's waist. The signals from the said range of strips is summed and that sum compared with zero. The transition of the said sum from a negative value to a positive one (associated with the stretching of the said sensors) is an indication of inspiration while the reverse transition, from positive to negative, is indicative of expiration.
Classification of respiratory phase—Voting
Particular groups of patients with peculiar or mixed pathology can produce conflicting indications of inspiration when subjected to the several abovementioned methods of determining respiratory phase. This embodiment takes as input the output from a selection of the abovementioned methods and derives a weighted vote as to which phase is present. If the said vote is above the Inspiratory Vote Threshold then an inspiration is indicated, if below the Expiratory Vote Threshold, then an expiration. If the said vote lays within the two thresholds then an Uncertain Phase is indicated.
Control of CPAP Treatment Apparatus
Referring to FIG. 20, the diagnostic signals 85 through 92 , and signals representative of the degree of laboured breathing, the degree of snoring and the classification of respiratory phase, can be used as part of a closed loop to determine and/or control the pressure setting of a Continuous Positive Airway Pressure (CPAP) treatment machine comprising a flow generator 128 that treats obstructive sleep apnea via air delivery tube and mask assembly 129 . A monitoring system 101 measures the respiratory parameters of the patient 1 in the manner described above and, if obstructive respiratory events are observed, transmits a control signal 130 to the CPAP flow generator 128 via CPAP control means 113 . The control signal 130 increases the treatment pressure if obstructive events are observed and slowly decreases it in the absence of obstructive events.
The aforesaid process of pressure control may be used either as a means of continuously controlling the treatment pressure during the time the patient sleeps or to determine, over the course of one or more nights, the optimum static treatment pressure to which the CPAP flow generator 128 should be set for continuing, subsequent treatment in the absence of the monitoring system 101 .
Thus, additionally and separately the aforesaid process of pressure control may be used to determine the pressure to which a CPAP treatment machine must be set for subsequent nights' treatment by the CPAP flow generator 128 alone. In this usage, monitoring system 101 is attached to the CPAP flow generator 128 for a diagnostic period comprising a small number of initial nights, typically between one and five, wherein it controls the pressure of the said CPAP flow generator 128 to limit the number of respiratory obstructive events experienced by the patient. At the end of each night the CPAP flow generator 128 is left programmed with the pressure determined by monitoring system 101 as the optimum for the limitation of the respiratory obstructions. At the end of the diagnostic period the monitoring system 101 is disconnected from the CPAP machine leaving the said machine programmed to the optimum treatment pressure determined.
In the above-mentioned diagnostic period monitoring system 101 follows a set protocol for determining the pressure setting or settings for the CPAP treatment machine. This protocol is open to modification by clinical staff but typically determines the range of pressures needed to reduce the number of apneas and hypopneas to below a preset number, typically 6 per hour. The protocol makes use of above-mentioned diagnostic accuracy indicators 87 and 90 plus other means to reduce the effect of artefacts causing too high a pressure determination. The protocol may advantageously take into consideration diagnostic measurements made over several nights. The above-mentioned diagnostic period can be repeated, for example annually, to maintain the setting of the CPAP flow generator 128 near its optimum.
In the above-mentioned diagnostic period monitoring system 101 produces a report at the end of said diagnostic phase that indicates the main physiological observations of the study and which may assist in the choice of CPAP treatment machine type. Additionally, the report highlights the occurrence of anomalous respiratory behaviour, including the occurrence of central apneas, that may contraindicate conventional CPAP treatment.
It is sometimes advantageous in sleep studies to have a moving or still image of the patient at various times during the night, particularly in coincidence with notable respiratory events. Conventionally, time synchronised video cassette recorders (VCRs) are used, allowing retrospective access to relevant sections of the video tape via computer control. One problem with this arrangement is the need for a video player to effect playback. The invention uses the monitoring system 101 to trigger a video camera that is aimed at the patient so that only the frames immediately preceding and succeeding a notable respiratory event are recorded as a video clip.
Further, using existing MPEG type compression techniques, the aforesaid video clip may be digitised and stored on computer disk 107 with the rest of the physiological information. This allows, on subsequent review, the replay of the video clip in a window on the computer screen at the same time as the physiological data is being observed, without the need for a video player.
As an alternative implementation, particularly for home use, the main recording medium 107 may be the tape of a conventional VCR, the video channel of which records the patient video clips, the audio channel of which records, in digitally modulated form, such as the output of a line modem, a combination of the above-mentioned digitised signals 60 , the above-mentioned basic derived signals 64 et seq. and the above-mentioned diagnostic signals 85 et seq.
The recording of snore is also a factor in the monitoring of partially obstructed breathing and there remain subtleties of sound that need the human ear to determine. Thus in review mode the option exists for listening to the snore component of the originally recorded signals, processed for snore detection using the high pass filter as in the derivation of basic derived signal 75 can optionally be played out in real time via sound output means 114 , typically a multimedia sound card such as those sold under the registered trademark “SOUNDBLASTER”, connected to computing means 104 . Another option allows the snore signals to be listened to at a review speed faster than real time.
Referring to FIG. 21, polygraph input means 110 is provided as a means of integrating the system described above with existing clinical recording systems in both sleep laboratories and other clinical environments such as intensive therapy and coronary care units. The polygraph input means 110 provides a method of outputting from the system indications of the states of diagnostic signals 85 - 92 in a form that can be input to the recording system of, for example, a polygraph (shown in FIG. 23) via a physiological input channel of the polygraph. The advantage of the polygraph input means 110 is that no specialist interface need be available in the polygraph, only an unused analogue physiological input channel such as that used for an ECG or EMG, with an input range of between approximately 10 mV and 1 V. Once the signal is input to the polygraph it can be automatically reviewed in conjunction with the conventional input signals using the standard review procedure of the polygraph.
As shown in FIG. 21, polygraph input means 110 comprises computer interface means 116 which is connected to an at least 4 bit wide parallel digital output port of computing means 104 , isolation means 117 which electrically isolates the parallel digital outputs of computing means 104 from the isolated digital outputs 118 . The isolated digital outputs 118 are connected to an isolated digital to analog converter (DAC) 119 , the output 120 of which is attenuated by attenuator 121 and presented as an input 122 to a physiological signal input channel of a polygraph.
The polygraph input means 110 thus allows the input to a polygraph of a series of analog voltage steps, the amplitude of the steps being determined by the digital input applied to the isolated DAC 119 .
By rapidly changing the levels of the steps in a predetermined pattern, the output voltage of the polygraph input means 110 may be caused to trace letters and numbers that are recorded by the polygraph as a conventional analog input signal. FIG. 22 a shows a graph of voltage against time of the 7 by 5 element matrix 123 that is used to construct one of the alphanumeric characters 127 . Baseline 124 is the voltage output when the system is idling. Fast transitions 125 between dots 126 on the aforesaid matrix are almost invisible on the review screen, leaving the dots, for which the voltage is held constant for a preset time, visible as the matrix.
If the display of a particular character does not require a dot in a particular matrix position the said output voltage is returned to the baseline 124 for the duration of the said dot. In this manner a character may be traced out. FIG. 22 b indicates the tracing necessary to display the letter “A”.
The aforesaid facility enables computing means 104 to output alphanumeric forms of a selection of diagnostic variables 85 - 92 to the polygraph, shown in FIG. 23, allowing simultaneous comparison on the polygraph display 131 of the conventional physiological signals 132 being recorded and the diagnoses 133 of the system described above.
By using system 101 with a patient who is undergoing treatment with a CPAP flow generator, the effectiveness of the treatment may be assessed by determining the residual number of obstructive apneas that occur using the above-mentioned techniques.
The aforesaid assessment of effectiveness may also be used to verify that the patient has, in fact, been submitting to treatment by the CPAP flow generator or has been avoiding the same. System 101 can, therefore, also be used as a compliance monitor for CPAP treatment.
Further embodiments will now be described with reference to FIGS. 24 to 33 .
A die cut part 5 is seen in FIG. 24 where a number of sensor strips 5 are cut out from a single sheet of PVDF from which is also formed tail strip 5 A. Separate conductive tracks 17 and 17 ′ on each face of each of the sensor strips 35 (FIG. 25) are formed by selective etching or printing at the metallisation layers of the tail strip, 5 A to conduct the sensor signals to bus connector 42 A.
The PVDF film material is normally only produceable in strips that can be many metres long but which have a restricted width that may be too narrow to allow the manufacture of a large one-part multistrip assembly 9 in the form visualised in FIG. 24 . The one-piece form thus displayed is advantageous from a manufacturing point of view—whereby all the strips 5 are part of a single, die cut sheet and, further, in which the electrical connections from each strip 5 may be conducted from the strip via metallisation on integral tailstrip 5 A.
Advantages bestowed by the embodiment of FIGS. 24 and 25 are:
(a) cheaper cost of manufacture
(b) more closely matching of sensor electrical characteristics
(c) more precise location of sensor strips within the movement sensitive mattress
(d) additionally, the provision of an integral strengthening and location element which stabilises and orients the sensor strips.
FIG. 26 shows a further embodiment, which involves the cutting of a relatively narrow (typically 6 cm wide) sheet of PVDF 11 with a pattern illustrated in FIG. 26 a, consisting of a number (typically between 4 and 15) of staggered parallel cuts 14 separated by the required width of each sensor strip (typically 1 cm), and of length equal to that required in the aforesaid sensor strips 5 , typically 60 cm. The parallel cuts dissect out from the PVDF film, strips 5 whose length is limited only by the length of the said film and not its breadth. Subsequent to the aforesaid dissection, each of the strips 5 is folded into a position 90 degrees from its original orientation at its base 150 via a crease 152 oriented at 45 degrees to the said cuts (FIG. 26 b ). The residual unfolded element of PVDF sheet 10 serves as an integral tail strip 5 A which conducts the electrical signals away from the said sensor strips to a remote electrical connector. Thus can be achieved the goal of producing a single piece sensor system from a film of restricted width.
Additionally, PVDF sheet 11 may be manufactured with stabilising element 11 a (FIG. 27 a ) consisting of an integral portion of the said sheet which folds underneath and is glued to the sheet and to the folded sensor strips 5 (FIG. 27 b ). The said 45 degree creasing of the strips 5 is thus immobilised, thereby removing any tendency for the strips 5 to return elastically to their original orientation.
FIG. 28 shows in more detail the electrical connections 17 from each sensor strip 5 along tail strip 5 A to bus connector 42 A. Normally there will be two separate connections 17 and 17 ′ from each of the sensor strips 5 , one from each face.
In another, simpler configuration, one face of each of the strips 5 is connected in common and that single common connection is conducted to bus connector 42 A along with the single connections from the obverse sides of each individual strip (FIG. 29 a ).
In a further simplification, all or some of the top faces of the said sensor strips may be connected in common and, separately, all the obverse faces may be likewise connected in common, to give just two electrical connections to the assembly (FIG. 29 b ). Such a simplification no longer allows the signal from each of the said sensor strips to be recorded separately, rather the output electrical signal is the sum of all the individual responses.
Optionally, further conductive layers or films may be applied over the entire area of the PVDF film 11 to shield the aforesaid connections from external electrical interference.
FIGS. 30 a and 30 b show in more detail the design of the conductive metallisation 13 on the top surface (FIG. 30 a ) and conductive metallisation 14 on the obverse (FIG. 30 b ) which collect the strain-generated charge from the strip and conduct it to the bus connector 42 A. Electrical charge is only conducted from the faces of the sensor strips 5 when each opposing face is metallised with conductive layers which overlap. In order to limit the area of sensitivity to that of the strip itself, the opposing metallisation patterns are staggered in the region 15 & 16 of said 45 degree crease and, thereafter, on tail strip 5 A. This renders the region of the said crease and the tail strip insensitive to any strains that maybe imposed thereon. This is important because the creasing causes disproportionate strain to be experienced at the crease.
In all the above-mentioned sensor configurations the separate option exists (FIG. 31) to curl sensor strip 5 round the edge of mounting foam sheet 7 B, allowing the tail strip 5 A and bus connector 42 A to be located away from patient contact. This advantageously removes any difference in stiffness that may be felt by the patient when lying on tail strip 5 A or bus connector 42 A and further protects the said bus connector and associated wires from potential physical damage.
When placing a said movement sensitive mattress on top of a conventional mattress, if the lateral dimensions of the two mattresses differ then the patient on the bed may well be discomfited. By making full use of the inherent thinness of the above-mentioned sensor assemblies the complete movement sensitive mattress may be mounted in an assembly less than 3 mm in thickness, allowing its easy and comfortable location on a range of conventional mattress sizes.
The thin movement sensitive mattresses described above can be regarded as a movement-sensitive sheet.
It may be desirable that the sensor strips 5 be enclosed in a waterproof envelope. However, the use of a sheet of neoprene or similar rubber to effect the waterproofing function can be clammy and uncomfortable. In order to improve comfort in this regard the construction of FIG. 32 a is used. Movement-sensitive mattress or sheet 2 ′ is constructed as described above with sensor strips 5 connected to tail strip 5 A and bus connector 42 A, the assembly thereof being sandwiched between thin neoprene or other suitably waterproof, flexible sheet 6 A. The said sheet 6 A is, however, perforated with holes 6 B that allow the assembly to “breathe”—that is, to facilitate the diffusion of humidity from the area in contact with the patient to the conventional bedding beneath the said movement sensitive mattress or sheet. The location of the sensor strips 5 are optionally located by web components 6 C.
In a further simplification to the above-mentioned design for increased patient comfort, the sensor strips 5 may be enclosed by the waterproof envelope 6 A only in the immediate vicinity thereof (FIG. 32 b ). In this configuration gaps 6 D between the enclosed sensor strips 5 facilitate the above-mentioned diffusion of humidity away from the subject.
FIG. 32 c shows an arrangement of six sensors 5 ′ arranged at the edge margin of the mattress 2 . Lateral strain elements 162 , acting to channel vertical body displacement to the respective sensor 5 ′ are provided. If preferred, a series of alternating slits 160 can be provided to decouple or isolate adjacent strain elements 162 . In another form, channelling of the lateral strain to each sensor 5 ′ may be achieved by use of a substrate material (not shown) in which the lateral (left-to-right) stiffness is significantly greater than the longitudinal (head-to-toe) direction.
In another implementation which improves the ability to locate accurately the sensor strips 5 and aids subject comfort, the movement-sensitive mattress or sheet 2 ′ is mounted on a carrier sheet 7 ′ typically made of cotton or an equivalent porous bed sheeting material or net (FIG. 33 ). The mounting method for the construction may be permanent, whereby movement-sensitive mattress or sheet 2 ′ is permanently bounded to carrier sheet 7 ′, or removable, whereby movement-sensitive mattress or sheet 2 ′ is attached to carrier sheet 7 ′ by fastenings such as haberdashers' press studs or “VELCRO”™ hook and loop material. The construction of carrier sheet 7 ′ can, advantageously, follow the form of a conventional “fitted” bedding sheet whereby an elasticated border (not shown) holds the carrier sheet 7 ′ on a conventional mattress 3 .
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A movement sensitive mattress has a plurality of independent, like movement sensors for measuring movement at different locations on the mattress to generate a plurality of independent movement signals. The signals are processed to derive respiratory variables including rate, phase, maximum effort or heart rate. Such variables can be combined to derive one or more diagnostic variables including apnea and labored breathing classifications.
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This application is a continuation of application Ser. No. 535,296 filed June 8, 1990, which is a continuation of Ser. No. 185,345 filed April 25, 1988, which is a continuation of Ser. No. 815,057 filed Dec. 31, 1985, all abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a recording apparatus in which recording operation is conducted by shifting a belt-shaped ribbon, such as a typewriter.
2. Description of the Prior Art
Recent developments in recording apparatus have realized economy in power consumption and miniaturization, and typewriters are now capable of various editing functions through the application of electronic technologies. However such developments are still not enough in certain areas. For example, for achieving control of advancement for various ribbons, it has been considered to prepare various cassettes corresponding to respective ribbons and incorporating different decelerating mechanisms. However such methods require different cassettes according to the ribbons, thus increasing the cost of the apparatus.
Also electric power is wasted since a constant voltage is supplied for drive regardless of the load.
Moreover, there have been required separate power supply circuits for a ribbon motor and a linear pulse motor, with a further separate selector circuit, so that the circuitry has inevitably been complex.
Furthermore, in the case of an abnormality for example in the descending motion of the ribbon, such as the absence of descent of the ribbon even after a predetermined time, the apparatus may develop a failure in trying to lower the ribbon.
Still further, noise generation is unavoidable in the carriage movement, particularly over a long period, since a constant voltage is always applied.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a recording apparatus capable of shifting and advancing a ribbon in a more efficient and effective manner with a simple structure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a typewriter embodying the present invention;
FIG. 2 is a perspective view of an output device B;
FIG. 3 is a lateral view of the output device B seen from a direction of arrow A shown in FIG. 2;
FIGS. 4 to 6 are schematic views showing the function of a ribbon lifting mechanism shown in FIG. 3;
FIGS. 7, 8-1 to 8-2 and 9-1 to 9-4 are schematic views showing the structure function of a cam gear and a cam lever;
FIGS. 10 and 11-1 to 11-2 are schematic views showing the structure and function of a ribbon winding shaft;
FIGS. 12 and 13 are schematic views showing the function of a switching solenoid;
FIGS. 14 to 16 are schematic views showing the opposite side of a ribbon frame;
FIG. 17 is a circuit diagram of a control circuit of an electronic typewriter;
FIG. 18 is a detailed block diagram of a control logic circuit and a keyboard logic circuit;
FIG. 19 is a detailed circuit diagram of a voltage switching circuit and a driving circuit;
FIG. 20 is a timing chart for motor protection;
FIG. 21 is a circuit of a down detector and a left-end detector;
FIGS. 22-1 and 22-2 are a flow chart of an output sequence of an MPU;
FIG. 23 is a flow chart for key entry process for other than character keys;
FIG. 24-1 is a flow chart for key entry process for a space key;
FIG. 24-2 is a flow chart for key entry process for back-space key;
FIG. 25 is a flow chart for key entry process for a correction key;
FIGS. 26 to 31 are timing charts for a printing sequence;
FIG. 32 is a timing chart for a corrected printing sequence; and
FIGS. 33A and 33B are a timing chart showing an abnormality in the down function of a ribbon frame.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now the present invention will be clarified in detail by embodiments thereof shown in the accompanying drawings. FIG. 1 is a perspective view of a typewriter in which the present invention is applicable, wherein shown are a keyboard 100 comprising alphabet keys, numeral keys, editing function keys etc.; a platen 1; an output medium 2 such as paper; and an output device B for printing desired information on the paper 2 as will be explained later.
In the following there will be given a detailed explanation on the output device B. FIG. 2 is a perspective view of the carriage B shown in FIG. 1, while FIG. 3 is a lateral view seen from a direction A in FIG. 2, and FIGS. 4 to 6 are schematic views of a ribbon lifting mechanism respectively showing a ribbon down state, a ribbon lifted state for printing and a ribbon lifted state for correction. FIGS. 7 to 9 are schematic views showing the structure and function of a cam gear and a cam lever. FIGS. 10, 11-1 and 11-2 are schematic views showing the structure and function of a ribbon winding shaft, and FIGS. 12 and 13 are schematic views showing the function of a switching solenoid. Also FIGS. 14 to 16 are schematic views of a correction ribbon feeding mechanism.
As shown in FIG. 2, the output unit or carriage B is mounted on a slider 50 of a linear motor and moves in the longitudinal direction thereof for printing.
An unrepresented type-selecting motor, provided in the carriage, selects a type from a daisy-wheel type element 3, and the thus selected type is hit by a hammer 4a of a solenoid unit 4 for making a print on the paper 2.
A ribbon frame 6, made of a metal plate, supports exposed portions 7a, 8a of a ribbon of a printing ribbon cassette 7 and a correction ribbon 8 at vertically different positions, and is rendered rotatable, as indicated by arrows a, b in FIG. 3, about a fulcrum 9 formed on a carriage frame 5.
A spring 10 applies a biasing force for lifting the frame 6 in the direction of arrow a, but the ribbon cassette is maintained in a ribbon down position lower than the printing position, since a roller 6a fixed in an extended part of the ribbon frame 6 as shown in FIG. 4 is retained by a roller guide wall 11a of a cam lever 11. As shown in FIG. 7, the cam lever 11 is provided with a cylindrical part 11b incorporating therein a cam pin spring 22 and a cam pin 23. By means of the cam pin spring 22, the cam pin 23 is pressed into a cam groove 24a of a cam gear 24. The cam lever 11 is rotatably supported on a shaft 12 projecting from the carriage frame 5.
As will be apparent from the above-explained structure, the ribbon frame 6 is rendered rotatable about the fulcrum 9, and is normally biased upwards by the spring 10, but the upward motion is prohibited as the roller 6a engages with the roller guide wall 11a of the cam lever 11. The guide lever 11 is freely rotatable on the shaft 12, and the rotational position of the guide lever 11 finally determines the stop position of the ribbon frame 6. The rotational position is determined by the rotational position of the cam gear 24.
The cam gear 24 is rotatably supported on a shaft 13 projecting from the carriage frame 5, and is provided with a cam groove 24a of varying depth. The cam pin 23 engages with the cam groove 24a, and follows the depth thereof by extending and retracting in directions S and T shown in FIG. 7 through the function of the spring 22, thus tracing the groove in one direction, wherein the tracing in the groove 24a is always defined by rotation of the cam lever 11 about the shaft 12.
In the following there will be given a further explanation of the cam gear 24, while making reference to FIGS. 8-1, 8-2, 9-1, 9-2, 9-3 and 9-4 showing the mode of rotation thereof and FIG. 11-1 showing the detailed structure thereof. At first referring to FIG. 8-1, hatched areas indicate areas raised from the plane of the drawing, and symbols "." indicate a shoulder raised at the hatched area side. Reference numeral 24a indicates a groove while symbols "+" define areas higher than the groove. As shown in FIGS. 7 and 11-1, the cam pin traces the groove 24a while extending or receding in a direction e. Thus, the cam pinlocated at 23 in FIG. 8-1 can move along an arrow marked with "o" only. The cam pin 23, sliding with the spring 22, cannot pass a shoulder from a deeper part to a shallower part, but can pass a shoulder from a shallower part to a deeper part or move along a gradual change of depth.
Also in FIG. 8-2, the cam pin can move along an arrow marked with "o" for the same reason. Thus, in the case a pinion gear 26 is rotated in a direction f' shown in FIG. 4 to rotate the cam gear in a direction f, the cam gear moves as shown in FIG. 9-1. On the other hand, in case the pinion gear is rotated in a direction g' to rotate the cam gear in a direction g, the pin moves as shown in FIG. 9-2.
In general, the cam pin 23 moves along a groove of larger diameter shown in FIGS. 8-1 to 9-2 in the clockwise movement and along a groove of smaller diameter in the counterclockwise movement, and combinations of these movements can achieve various control as will be explained later.
Winding mechanism for printing ribbon
In the following there will be explained a winding mechanism for the printing ribbon. In FIG. 11-1, the pinion gear 26 is provided with a bevel gear 26a and a flat gear 26b for driving said cam gear 24. FIG. 10 shows the structure of a ribbon winding shaft driven by the bevel gear 26a. The bevel gear 26a shown in FIG. 11-1 meshes with a bevel gear 27 having ratchet teeth 27a continuously extended to 27b to drive a ribbon winding shaft 28 shown in FIG. 10. Thus, rotation of the pinion gear 26 in a direction f' shown in FIG. 4 causes rotation of the bevel gear 27 in a direction f" shown in FIGS. 10 and 11-1. As the ratchet teeth 27a provided above the bevel gear engage with a claw 29 rotatably supported by a pin 28a of the ribbon winding shaft 28 and biased by a spring 30, rotation of the bevel gear in the direction f" induces rotation of the shaft 28 in a direction f"'. Around the shaft 28 there is provided a clutch spring 31 to release a clutch in the rotation of the shaft in the direction f"' but to lock the shaft in the opposite rotation. Consequently, rotation of the pinion 26 in the direction f' shown in FIG. 4 causes rotation of the shaft 28 in the direction f"' whereby an engaging claw 28b, engaging with an unrepresented feed gear of the ribbon cassette, advances the ribbon. On the other hand, when the pinion rotates in the direction g' shown in FIG. 4, the bevel gear 27 rotates in a direction g" but the shaft is prevented from rotation by the clutch spring 31. In this state the ratchet teeth 27a are disengaged from the claw 29 to disconnect the shaft 28 from the gear 27, so that the ribbon is not advanced. FIG. 11-2 shows the form of engaging portion 29a of the claw 29 engaging with the ratchet teeth 27a and the relation with the direction of rotation of the bevel gear 27. When the gear is rotated in the direction f", the left-hand end of a tooth 27a engages with the right-hand end of the engaging portion 29a to advance the ribbon. In the opposite rotation, the ribbon winding shaft is not rotated since a left-sided slanted face of the engaging portion 29a slides over the tooth 27a. The spring 30 biases the claw 29 toward the center of the bevel gear, and the engaging force between the engaging portion 29a and the teeth 27a is determined by the clutch spring 31 and spring 30.
Printing operation with correctable ribbon
In the following there will be explained the printing operation with a correctable (erasable) ribbon. When the cam is rotated in the direction f from the position shown in FIG. 4, the ribbon is shifted from the aforementioned down state to a lifted state shown in FIG. 5, by means of the function of the cam lever and roller 6a, while the ribbon is advanced by the aforementioned engaging claw 28b. The lifted position of the ribbon is determined by the engagment of a lift latch 6b provided in the ribbon frame 6 and an engaging portion 32a of a switching lever 32. Immediately thereafter the hammer 4 is activated to perform a printing operation, and subsequently the ribbon returns to the down state shown in FIG. 4. In this operation the pinion 26 shown in FIGS. 11-1 and 5 is rotated in the direction g' to lower the ribbon frame 6 against the function of the spring 10, without advancing the ribbon. As explained before, in the rotation of the pinion 26 in the direction g', the claw 29 is disengaged from the gear 27 as shown in FIG. 11-2 so that the ribbon winding shaft is not rotated. When the ribbon frame 6 is depressed as explained above, a down sensor 33, such as a limiter, is covered by a shield plate 6c provided on the ribbon frame 6, whereby the downward movement is terminated to restore the down state shown in FIG. 4.
In the case of a continuous printing operation, the cam pin 23 continues to rotate clockwise as shown in FIG. 9-1, with corresponding ribbon advancement since the rotation corresponds to the direction f shown in FIG. 4, and the ribbon frame is maintained at the lifted position during the operation.
Correcting operation
In the following there will be explained a correcting operation. FIGS. 12 and 13 illustrate the switching lever 32 and a solenoid activating the same. In response to an instruction for correction entered from the keyboard 100, the switching solenoid 34 attracts a chip 32b fixed on the switching lever 32 as shown in FIG. 13, thus rotating the lever 32 around a shaft 35 in a direction h. In this state the cam is rotated in the direction g shown in FIG. 4 to lift the printing ribbon without advancement, whereby the clutch lift 6b does not engage with the engaging portion 32a of the lever and the ribbon frame is lifted until a stopper portion 6d thereof meets a final stopper 5a provided on the carriage frame. Thus the correction ribbon 8 is lifted to the printing position (FIG. 6). The hammer 4 is activated in this state to correct a mistyped print, and the ribbon is then lowered to the down position shown in FIG. 4. In this operation, the cam is rotated first in the direction g to guide the cam pin 23 through the shoulder portion of the groove and is then slightly reversed in the direction f to guide the cam pin 23 securely to the maximum lift position of the cam, as shown in FIG. 9-3. It is however possible also to dispense with the reverse rotation.
FIGS. 14 to 16 are schematic lateral views of the ribbon frame seen from the opposite side, principally illustrating an advancing mechanism for the correction ribbon, and respectively show a down state, a lifted printing state and a correcting state, corresponding to the states shown in FIGS. 4 to 6.
A winding ratchet wheel 14 for winding the correction ribbon 8 on a shaft 14a is rotatably supported on the ribbon frame 6. A ratchet 15 engages, by means of a plastic spring 16, with the ratchet wheel 14 to prevent reverse rotation thereof. A feed claw 17 is rotatably supported on the carriage frame 5 and engages with the ratchet wheel 14 by means of a plastic spring 18.
In the above-explained structure, the ratchet wheel 14 is rotated by a tooth to advance the correction ribbon by one character, in the course of movement of the ribbon frame from the down position (FIG. 14) through the printing position (FIG. 15) to the stand-by position (FIG. 16) and finally to the down position (FIG. 14).
Printing operation with multi-use ribbon cassette
A multi-use ribbon, allowing plural prints in the same position, needs less advancement compared with the correctable ribbon. Consequently the ribbon will be wasted in the case of single printing operation if the multi-use ribbon is controlled in the same manner as the aforementioned correctable ribbon.
Consequently, as in the aforementioned print-correcting operation, the cam is rotated in the direction g shown in FIG. 4 to lift the ribbon frame without the ribbon advancement. In this state the ribbon is lifted only to the printing position since the switching solenoid 34 is not energized. The movement of the cam pin in this state is shown in FIG. 9 - 4. The lifting operation of the ribbon by the cam 24 is completed when the cam pin 23 reaches a point i, and the cam 24 is then rotated in the direction f by a predetermined amount to bring the cam pin 23 from the point i to a point j. In this operation the multi-use ribbon is wound by a predetermined amount corresponding to the rotation in the direction f. Thereafter the cam 24 is rotated again in the direction g to return the ribbon to the down position without ribbon advancement. In the case of a continuous printing operation, the cam pin 23 circulates the maximum lift position of the cam, in the same manner as in the continuous printing operation with the correctable ribbon.
In the following there will be explained driving circuits and control sequences for the ribbon motor, switching solenoid, hammer, linear stepping motor, wheel motor and down sensor.
FIG. 17 is a circuit diagram of a control circuit of an electronic typewriter embodying the present invention, wherein a control logic circuit 51, controlled by input signals from a keyboard logic circuit 50, supplies control signals DS, LEFT, V L V H , CV, FM, SS, WM, CM, RM, PM to various loads in driving circuit 60, after suitable amplification by unit driving circuit 53-59 in driving circuit 52. The loads include the hammer solenoid 61, switching solenoid 62, wheel motor 63, carriage motor 64, ribbon motor 65, platen device 66 etc. which are driven by the key actuations in the keyboard 100 and the above-mentioned control signals. Signals from sensors 68, including the down sensor and left limit sensor, are digitized in an analog-to-digital level converting circuit and are supplied to the control logic circuit 51 through signal lines DS, LEFT.
FIG. 18 is a detailed block diagram of the control logic circuit 51 and keyboard logic circuit 50.
In the control logic circuit 51 shown in FIG. 18, there is provided a micro processing unit (MPU) 69 which performs control in response to the input signals from the keyboard logic circuit 50 and which transmits and receives microinstructions and data to and from a read-only memory (ROM) 70, a random access memory (RAM) 71, an interface control logic circuit 72, a timer 73 and the keyboard through a common data bus DB in cooperation with an address bus ADB and a read-write bus R/WB. In such structure, the micro-processing unit (MPU) 69 executes the control process according to microinstructions stored in advance in the read-only memory 70 or in the random access memory 71. The timer 73 increases the content thereof according to code signals indicating time intervals supplied from the MPU through the data bus DB, and, after the lapse of a predetermined time, requests an interruption to the above-mentioned program to the MPU through a line LNT2. Also the keyboard logic circuit 50 requests, in response to a key actuation in the keyboard 100 and through an interruption signal line INT1, an interruption process according to a program stored in the RAM or ROM. Simultaneously microcoded key information, required for the interruption process, is supplied to the data bus DB.
On the other hand, the interface control logic circuit 72 latches microencoded drive signals and amplifies the control signals CV, HMSS, WM(1-4), CM(1-4), RM(1-4), PM(1-4) to the levels suitable for driving various loads.
FIG. 19 shows the details of the driving circuit 52 shown in FIG. 17, including, for example, the voltage switching circuit 53. A voltage selecting circuit 74 selects either of two voltages VH, VL according to a signal CV from the interface control logic circuit, for use as a common power supply voltage for driving the carriage motor and the ribbon motor. In the case where the signal CV is at an L-level, an open-collector inverter, employed for lever conversion, provides an H-level output signal to activate transistors Tr1, Tr2, whereby a high voltage V H is supplied to a point V+. On the other hand, in the case where the signal CV is at an H-level, the open-collector inverter provides an L-level output signal to turn off the transistors Tr1, Tr2, whereby a low voltage VL is supplied to the point V+ through a diode D1. A diode D2 protects the transistor Tr2 in the case of V+>VH.
Consequently efficient motor driving is possible by employing a high voltage in the case where a high torque is required tolerating colerating a low duty ratio, or a low voltage when a low torque is enough, but heat generation of the motor is to be considered because of a high frequency of use.
In the case where the carriage motor is driven with the H-level for a prolonged period, the ribbon motor is also energized with the H-level. However, if such drive leads to damage in the ribbon motor because of the duty ratio of the power supply, the ribbon motor may be appropriately deactivated by the MPU 72. Such mode of drive is shown in FIG. 20, in which the ribbon motor is deactivated by the MPU while the carriage motor is driven by the H-level signal. The ribbon motor is energized with the L-level signal to advance the ribbon while the carriage motor is driven with the L-level signal.
FIG. 21 is a circuit diagram of the down detector and left end detector 68 and the analog-to-digital level converting circuit 67. Since the circuit structure is the same, explanation will be given only to the down detector 33 in the following. In the down detector, a constant current is continuously given to a light-emitting diode (LED) of an interrupter, while a voltage Vcc is supplied through a resistor R3 to the collector as a phototransistor. Thus the collector potential V1 of the phototransistor is determined by the position of a shield positioned between the light-emitting diode and the phototransistor. A comparator compares the potential V1 with a reference voltage VZ1 determined by a Zener diode ZD1, and provides an output signal DS of L-level or H-level respectively when V1>VZ1 or V1<VZ1. The reference voltage VZ1 is selected between a potential V1 in the case of complete shielding and another potential V1 in the case of absence of shielding, and the comparator 1 is provided with a so-called hysteresis circuit composed of resistors R1 and R2, in order to stabilize the level of the output signal DS, even when the V1 and VZ1 are approximately equal.
FIG. 22 shows a flow chart for the output sequence executed by the MPU. Steps S1-S3 identify the presence of key entry, and step S2 identifies the time since the preceding printing operation to lower the ribbon from the printing position according to the time. In the case where a key entry is identified in step S1, a step S4 identifies whether the key is a character key, and, if not, the program proceeds to a step S5 to be explained later. In the case where step S4 identifies the actuation of a character key, the program proceeds to a step S6 to identify whether or not a ribbon lowering process is in progress. If so, a step S7 identifies the loaded ribbon, and, if it is a correctable ribbon, the program proceeds to a step S8 to interrupt the ribbon lowering operation. On the other hand, in the case where the step S7 idenfifies a multi-use ribbon, the program proceeds to a step S10 after confirming the completion of the ribbon lowering process in a step S9. Steps S10, S11, S12, S13, S14 and S15 advance the ribbon and select the key-entered character, while the ribbon is maintained in the lifted state.
Subsequently, steps S16 and S17 displace the carriage to the printing position, and a step S18 energizes the hammer to perform a printing operation, and the timer is set for controlling a next key entry and the ribbon lowering control. Then succeeding steps S19 and S20 set the amount of subsequent movement of the carriage, and move the carriage, and the program returns to point A.
FIG. 23 shows a flow chart for non-character key process shown in step S5 in FIG. 22. At first steps S31-S33 identify the actuated key and according to the result of said identification, there is executed a space key process (S34), a back space key process (S35), a correction key process (S36) or a process for other keys (S37).
FIGS. 24-1 and 24-2 show detailed flow charts of the aforementioned space key process and back space key process shown in FIG. 23. Since these two processes are alike, there will be only explained the space key process shown in FIG. 24-1. The carriage is first driven by a 2-phase energization with a high torque, but is then driven by a 1-2 phase energization for abating noise. At first a step S40 identifies whether or not a spacing operation is already in progress, i.e. in a repeat operation. In the case where the repeat operation is not in progress or in the case of a first spacing operation, the program proceeds to a step S41 to set a spacing operation flag for a next identification in the step S40. In the case of a first spacing operation, a step S42 clears a 1-2 phase drive flag in order to drive the carriage with 2-phase drive. Then steps S43 and S44 set the amount of movement of the carriage and execute the movement thereof.
On the other hand, in the case where the step S40 identifies that a spacing operation is already in progress, the program proceeds to a step S45 to renew the amount of movement, to set the 1-2 phase drive flag and to continue the spacing operation with low-noise 1-2 phase drive. Though a 4-phase stepping motor is employed in the present embodiment for displacing the carriage, it is also possible to use other motors. A 2-phase drive provides a high torque but is associated with large noise, while a 1-2 phase drive provides only a low torque but low noise level due to smoother rotation at the start of carriage drive.
These driving modes will not be explained in detail as they are already well known. The amount of moving space by the 2-phase drive at the start is 1/15, 1/12 or 1/10 inches according to a pitch selected by a pitch selector.
Now reference is made to FIG. 25 for explaining a correction key process shown in FIG. 23. After the ribbon reaches the down position in steps S51 and S52, a step S53 turns on the switching solenoid explained in relation to FIGS. 12 and 13, thereby preparing the ribbon frame for lifting to the correcting position in the ensuing procedure. A step S54 then starts the lifting of the ribbon, and a step S55 selects a character to be corrected, i.e. a character of an immediately preceding key entry. If a step S56 identifies the completion of the lifting, a step S57 turns off the switching solenoid. Then, if a step S58 identifies the completion of character selection in the step S55, the program proceeds to a step S59 to activate the hammer, and steps S60 and S61 lower the ribbon. At the lowering of ribbon, it is advanced as explained before.
The above-explained wheel motor for character selection, carriage motor, motor for elevating and lowering the ribbon and ribbon advancing motor are driven by storing the pattern of energized phases in the corresponding addresses of the interface control logic circuit 72 and setting the energizing time in the timer. When the timer expires an interruption signal is supplied to the CPU through the line INT2, and the pattern and energizing time of succeeding energized phases are set in the interruption process. The above-explained procedure is thereafter repeated for a number of predetermined steps. During the above-explained process there is set a flag indicating the continuation of the process, and the flag is reset upon completion of the procedure. The flag is set in the RAM.
The pattern of the energized phases and the table of energizing time are stored in the ROM. The timer is provided therein with three timer counters, in each of which a preset value is stepwise decreased at every predetermined interval, and an interruption signal is supplied to the CPU when the content of the timer counter reaches zero. The three timer counters are used for controlling the energizing times in three motors.
The character selection of the wheel motor is achieved by the CPU which drives the wheel motor by determining the direction of rotation and the number of steps, through the comparison of the current position of the wheel and the wheel position corresponding to an entered character key, making reference to a wheel position table in the ROM.
The above-explained printing sequence will be explained by timing charts. FIG. 26 is a timing chart showing the printing sequence in the case of single printing operation with a correctable ribbon. At first, in response to a key input signal KS, the wheel motor WM is activated to select a character corresponding to the key input. Simultaneously the ribbon motor is rotated in the forward direction f shown in FIG. 4 with a low voltage, thereby lifting the ribbon to the printing position and advancing the ribbon by a predetermined amount (see FIG. 9-1). After the ribbon advancement the hammer is energized to print a character. Thereafter the carriage motor is energized to move the carriage to a next printing position The low-level (15 V) driving voltage is employed in this state as will be apparent from the voltage switching signal. Then the ribbon motor is reversed with the high-level voltage (24 V) for lowering the ribbon, and, after the detection of the down position of the ribbon by the down sensor 33 shown in FIG. 2, the ribbon motor is further driven for a predetermined number of steps and is then turned off. A high-level signal from the down sensor indicates that the shield plate 6c shown in FIG. 2 is positioned in the limiter 33, corresponding to the down position of the ribbon.
FIG. 27 is a timing chart showing the continuous printing sequence with a correctable ribbon. At first, in response to a key input signal KS, the wheel motor WH, ribbon motor RH and hammer HM are activated in the same manner as in the single printing operation. In the presence of a succeeding key input within a predetermined period, for example in the course of movement of the carriage to a succeeding printing position, a subsequent printing operation is conducted while the ribbon is maintained in the lifted position (see FIG. 9-1).
FIG. 28 is a timing chart showing the printing sequence in the case where a key input takes place while a correctable ribbon is employed and is in the down position. The sequence up to (a) is the same as that in the single printing operation shown in FIG. 26. In the case where a key input (c) is present again in the course of descent (b) of the ribbon after printing, the wheel motor is energized to select a character. At the same time the reverse rotation of the ribbon motor with the high-level voltage is interrupted to terminate the descent of the ribbon, and the ribbon motor is driven forward with the low-level voltage to elevate the ribbon again to the printing position. Thereafter the hammer is activated to print a character.
In the following there will be explained the printing sequence in the case where a multi-use ribbon is mounted. FIG. 29 is a timing chart showing the printing sequence in a single printing operation. At first, in response to a key input, the wheel motor is activated and simultaneously the ribbon motor is reversed. The reverse rotation is conducted with the high-level voltage. As will be apparent from the signal level of the down sensor, the ribbon is initially at the down position, and the cam is rotated, from the corresponding initial position shown in FIG. 4, in the direction g shown in FIG. 4, and such high-level voltage is required in order that the cam pin 23 can pass the raised portion of the cam. The ribbon motor is thereafter rotated in the reverse direction with the low-level voltage, and is rotated in the forward direction f from a point (i) shown in FIG. 29, as the ribbon is advanced between i and j in the forward rotation of the cam as explained in relation to FIG. 9-4. Thereafter the hammer is activated to print a character, and the carriage motor is then activated to move the carriage to a next printing position. In the absence of other key inputs thereafter, the ribbon motor is rotated in reverse direction from a position shown in FIG. 5 to lower again the ribbon from the printing position. Thus the cam is rotated in the direction g to lower the ribbon frame. The ribbon is not advanced since the cam is rotated in the direction g, as already explained in relation to FIGS. 10 to 11-2. After the detection of the down position of the ribbon by the down sensor, the ribbon motor is further rotated in the reverse direction by several steps and is then stopped.
FIG. 30 shows the printing sequence in a continuous printing operation with a multi-use ribbon. The procedure up to a point (a) is the same as that shown in FIG. 29 and therefore will not be explained further. In this mode, if key inputs are given with an interval shorter than a predetermined time as shown in FIG. 27, printing operations can be conducted in continuous manner without descent of the ribbon as shown in FIG. 29. Printing speed is faster in the case of FIG. 30 than in FIG. 27 since the multi-use ribbon requires a smaller advancement, or a shorter forward rotating time of the ribbon motor.
FIG. 31 shows the printing procedure in the case where a key input is given while a multi-use ribbon is in the down position. The procedure up to a point (a) is the same as that shown in FIG. 29 or 30 and therefore will not be explained further. The ribbon motor is rotated in reverse direction from a point (b), with the high-level voltage, to lower the ribbon. In the presence of a key input in the course of the ribbon descent at a point (c), the descent of the ribbon is continued and the ribbon motor continues to be rotated in the reverse direction even after the down state of the ribbon is detected by the down sensor. After a point (d), the ribbon motor continues reverse rotation since the cam pin 23 has passed the raised portion of the cam as already explained in relation to FIG. 29, and then the ribbon motor is rotated in the forward direction to advance the ribbon by a predetermined amount from a point i to j as already explained in relation to FIG. 29. During the reverse rotation of the ribbon motor, the wheel motor is activated to select a character, and, after a point j, the selected type is hit by the hammer to form a print.
Now reference is made to FIG. 32 for explaining the sequence of correction print. First actuated is the correction key and a character to be corrected is entered. The character may be the character printed immediately before and stored in the memory, and can therefore be automatically selected upon actuation of the correction key. When an instruction for correction is given in this manner, the wheel motor is activated to select the character to be corrected, and the switching solenoid is energized, as explained in relation to FIGS. 12 and 13, to lift the ribbon to the position shown in FIG. 6. In this state, the cam 24 and the cam pin 23 are located as shown in FIG. 4. The direction of ribbon motor rotation is reversed with the high-level voltage until the cam pin 23 passes the raised portion of the cam as already explained in relation to FIGS. 29, 30 and 31, and the reverse rotation is then continued with the low-level voltage. Subsequently, at a point (a), the ribbon motor is rotated in the forward direction by a small amount to bring the cam to the maximum lift position, as already explained in FIG. 9-3. The function is similar to the ribbon advancement in the multi-use ribbon. After the ribbon is brought to the maximum lift position in this manner, the switching solenoid is deactivated and the correction ribbon is hit by the hammer to erase the already printed character. The correction ribbon may be an adhesive tape or a tape coated with white powder. After the erasure, the ribbon is lowered at a point (b), in the same manner as in FIGS. 26 and 29. It is to be noted, however, that the ribbon lowering operation in FIGS. 26 and 29 involves a change from a state shown in FIG. 5 to a state in FIG. 4, while the ribbon lowering operation in FIG. 32 involves a change from a state in FIG. 6 to a state in FIG. 4. Because of the difference in the distance of descent, the correction ribbon is advanced by a predetermined amount, by means of a ratchet mechanism, only in the descent from the correcting position shown in FIG. 32 to the down position of the ribbon.
Now reference is made to FIG. 33 for explaining a procedure in the case where the ribbon frame cannot descend to the position of the down sensor 33 for detecting the down position of the ribbon frame. In FIG. 33, (a) is a timing chart in the ordinary lowering operation of the ribbon. The ribbon is securely lowered, in normal condition, by reverse rotation of the ribbon motor in 18 to 70 pulse steps. FIG. 33(b) is a timing chart showing a case in which the down sensor does not detect the down state of the ribbon when the number, of steps of the ribbon motor exceeds a predetermined number, for example 72 steps, whereby an abnormality is detected and an abnormality signal is turned on to provide an alarm, for example a buzzer sound.
As previously explained in detail, the foregoing embodiment utilizes the combination of a ribbon motor and a cam to perform printing with a correctable fabric ribbon and to advance the ribbon in the forward rotation of the ribbon motor, and to lift a multi-use ribbon and a correction ribbon in the reverse rotation. Also there may be employed ribbons of different amounts of advancement since the ribbon is lifted by the reverse rotation of the ribbon motor, independently of the ribbon advancement and the ribbon motor is then rotated in the forward direction by an arbitrary amount after the ribbon is lifted. Furthermore, mass-produced inexpensive cassettes can be employed for different ribbons, since the amount of ribbon advancement can be controlled by the ribbon motor without any modification in the cassette. Different ribbons can be simply housed in such a cassette. On the other hand, the ribbon motor is driven with a high voltage only when the ribbon frame is lowered but is driven with a low voltage for ribbon advancement to avoid electric power waste and to enable control with a high duty ratio. In addition, the ribbon motor and the linear pulse motor (LPM) can have a common power supply, so that voltage switching can be achieved through a single signal line. In this manner the circuit structure can be simplified and rendered inexpensive. Furthermore, the activation of the ribbon motor is prohibited in a range of excessively high duty ratios, in order to avoid damage to the motor cause by a constant high voltage applied thereto.
In the case of an abnormality in the lowering operation of the ribbon, the lowering operation is terminated after a predetermined number of pulses to prevent damage to the apparatus, and an acoustic or visual display is provided. In this manner it is rendered possible to know the abnormality quickly and to prevent breakage of the apparatus. Furthermore, in the case where the carriage has to travel a long distance, the drive is achieved with low voltage pulses (15 V) at the accelerating and decelerating periods and with high voltage pulses (24 V) in the intermediate constant speed period, in order to abate the noise in the accelerating and decelerating stages.
Similarly, the repeated operation of the space and back space keys can be achieved with lowered noise level by a 2-phase drive in the start period and a 1-2 phase drive thereafter.
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A recording apparatus for recording onto a recording medium and capable of correcting an erroneous recording includes an ink sheet mounting section on which an ink sheet for effecting the recording medium is mountable, a device for effecting the ink sheet to the recording medium, and a motor for driving the ink sheet. By a driving force produced by one directional rotation of the motor, the recording ink sheet is moved between an effecting position where the recording ink sheet is effected by the effecting device and a retracted position where the recording ink sheet retracts from the effecting position. Also, by a driving force produced by the motor, the correcting ink sheet is moved between an effecting position wherein the correcting ink sheet is effected by the effecting device and a retracted position where the correcting ink sheet retracts from the effecting position. Further, a conveying device conveys the correcting ink sheet without conveying the recording ink sheet in response to movement of the correcting ink sheet between the effecting and retracting positions.
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FIELD OF THE INVENTION
This invention relates to compounds that are antagonists of dopamine D4 receptors and to methods of treating psychosis and schizophrenia using a compound that is an antagonist of dopamine D4 receptors.
BACKGROUND OF THE INVENTION
Dopamine is a neurotransmitter that is found in the brains of animals, including humans, and is essential for proper nerve signal transmission. It is well-known that certain compounds block or inhibit the binding of dopamine to dopamine receptors. Such compounds are called dopamine receptor antagonists. It is also well-known that dopamine receptor antagonists are useful in the treatment of schizophrenia and psychosis.
Recently, it has been discovered that more than one type of dopamine receptor exists, and that dopamine receptor antagonists can preferentially inhibit one type of dopamine receptor over another. Two major families of dopamine receptors have been identified and named the D1 and D2 families. In the D2 family, three distinct receptor subtypes have been identified as D2, D3, and D4.
The distribution and concentration of the subtypes of receptors varies in different regions of the brain. For example, D2 receptors are found in high concentrations in the frontal cortex and limbic region, which are associated with cognitive and emotional function and also in striatal regions which are associated with motor activity.
D2 subtype receptor antagonists have been used to treat psychosis and schizophrenia, but have undesirable extrapyramidal side effects and produce tardive dyskinesia which is thought to be due to their striatal effects. In contrast, D4 receptors are found in highest concentrations in the frontal cortex and limbic regions. Therefore, D4 receptor antagonists can produce antipsychotic efficacy and lack the extra pyramidal side effects and tardive dyskinesias. Moreover, it has been observed that the levels of dopamine D4 receptors are elevated in schizophrenics.
Thus, it would be useful to have compounds that are selective D4 antagonists for the treatment of psychosis and schizophrenia.
SUMMARY OF THE INVENTION
The present invention provides compounds having the Formula I ##STR1## R is O or N; Q is a bond, CH, or CCH 3 ;
X is O, S, or NH;
Y is NH or a bond;
Z is O, S, NH, or a bond;
a, b, and c are independently 0 to 3;
R 1 is hydrogen or R 1 and R 2 taken together form a benzene ring;
R 2 is hydrogen; and
R 3 and R 4 are independently hydrogen, hydroxyl, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, halogen, nitro, phenyl, cyano, carboxy, carboxamido, carboalkoxy or hydroxymethyl, and the pharmaceutically acceptable salts, esters, amides, and prodrugs thereof.
In a particular embodiment of the compounds of Formula I, J is ##STR2##
In another particular embodiment, J is ##STR3##
In another particular embodiment, J is ##STR4##
In another particular embodiment, J is ##STR5##
In another particular embodiment, J is ##STR6##
In another particular embodiment, J is ##STR7##
In a preferred embodiment, a is 0, b is 2, c is 3, X is O, Y is NH, and Z is O.
In another preferred embodiment, a is 1, X is NH, b is 2, and Y is NH, c is 0, and Z is a bond.
In another preferred embodiment, a is 1, X is NH, b is 2, Y is O, c is 0, and Z is a bond.
In another preferred embodiment, R 3 and R 4 are independently hydrogen, C 1 -C 6 alkyl, halogen, or hydroxymethyl.
In another preferred embodiment, R 3 and R 4 are hydrogen.
In a preferred embodiment, the compound of Formula I is a hydrohalide salt.
In a more preferred embodiment, the hydrohalide salt is the hydrochloride salt.
In another preferred embodiment, a compound of Formula I has the structure ##STR8##
In another preferred embodiment, a compound of Formula I has the structure ##STR9##
Also provided by the present invention is a pharmaceutically acceptable composition that comprises a compound of Formula I.
Also provided by the present invention is a method of treating psychosis, the method comprising administering to a patient having psychosis a therapeutically effective amount of a compound of Formula I.
Also provided by the present invention is a method of treating schizophrenia, the method comprising administering to a patient having schizophrenia a therapeutically effective amount of a compound of Formula I.
Also provided by the present invention are the compounds
6- 2-(3-Phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride;
(3-Phenoxy-propyl)- 2-quinolin-6-yloxy)-ethyl!-amine hydrochloride;
8- 2-(3-Phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride;
7- 2-(3-Phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride;
2-(Dibenzofuran-2-yloxy)-ethyl!-(3-phenoxypropyl)-amine hydrochloride;
4-Methyl-7- 2-(3-phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride;
4-Methyl-6- 2-(3-phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride;
2-(Benzofuran-5-yloxy)-ethyl!-(3-phenoxy-propyl)-amine hydrochloride;
7- (2-Phenylamino-ethylamino)-methyl!-chromen-2-one;
7-{ 2-(3-Chloro-4-hydroxymethyl-phenylamino)-ethylamino!-methyl}-chromen-2-one;
7-{ 2-(3,4-Dimethyl-phenylamino)-ethylamino!-methyl}-chromen-2-one;
7- (2-p-Tolylamino-ethylamino)-methyl!-chromen-2-one;
7-{ 2-(3-Chloro-phenylamino)-ethylamino!-methyl}-chromen-2-one dihydrochloride;
7-{ 2-(4-Chloro-phenylamino)-ethylamino!-methyl}-chromen-2-one;
7-{ 2-(3-Chloro-4-methyl-phenylamino)-ethylamino!-methyl}-chromen-2-one;
6- (2-Phenylamino-ethylamino)-methyl!-chromen-2-one;
6-{ 2-(3-Chloro-4-methyl-phenylamino)-ethylamino!-methyl}-chromen-2-one hydrochloride;
7- (3-Phenylamino-propylamino)-methyl!-chromen-2-one;
6- (2-Phenoxy-ethylamino)-methyl!-chromen-2-one hydrochloride;
6- (2-p-Tolyloxy-ethylamino)-methyl!-chromen-2-one;
6-{ 2-(4-Chloro-phenoxy)-ethylamino!-methyl}-chromen-2-one;
7- (2-Phenoxy-ethylamino)-methyl!-chromen-2-one;
7- (2-p-Tolyloxy-ethylamino)-methyl!-chromen-2-one;
7-{ 2-(4-Chloro-phenoxy)-ethylamino!-methyl}-chromen-2-one;
7- (2-Phenylsulfanyl-ethylamino)-methyl!-chromen-2-one hydrochloride;
7- (3-Phenyl-propylamino)-methyl!-chromen-2-one;
7-{ 3-(4-Chloro-phenoxy)-propylamino!-methyl}-chromen-2-one;
7- (3-p-Tolyloxy-propylamino)-methyl!-chromen-2-one; or
6- (3-Phenoxy-propylamino)-methyl!-chromen-2-one.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides compounds having the Formula I ##STR10## wherein J is ##STR11## R is O or N; Q is a bond, CH, or CCH 3 ;
X is O, S, or NH;
Y is NH or a bond;
Z is O, S, NH, or a bond;
a, b, and c are independently 0 to 3;
R 1 is hydrogen or R 1 and R 2 taken together form a benzene ring;
R 2 is hydrogen; and
R 3 and R 4 are independently hydrogen, hydroxyl, C 1 -C 6 alkyl, C 1 -C 6 alkoxy, halogen, nitro, phenyl, cyano, carboxy, carboxamido, carboalkoxy or hydroxymethyl, and the pharmaceutically acceptable salts, esters, amides, and prodrugs thereof.
The term "alkyl" means a straight or branched chain hydrocarbon. Representative examples of alkyl groups are methyl, ethyl, propyl, isopropyl, isobutyl, butyl, tert-butyl, sec-butyl, pentyl, and hexyl.
The term "alkoxy" means an alkyl group attached to an oxygen atom. Representative examples of alkoxy groups include methoxy, ethoxy, tert-butoxy, propoxy, and isobutoxy.
The term "halogen" includes chlorine, fluorine, bromine, and iodine.
The term "carboxy" means a carboxylic acid functional group, i.e., --CO 2 H.
The term "carboalkoxy" means an alkyl ester of a carboxylic acid functional group, i.e., --CO 2 alkyl. A preferred carboxyalkyloxy group is carboxymethoxy.
The term "carboxamido" means a --CONH 2 group. It is noted that the two hydrogens on the nitrogen atom may be substituted with substituents that are well-known to those skilled in the art, such as alkyl groups.
The symbol "--" means a bond.
The term "patient" means humans.
A "therapeutically effective amount" is an amount of a compound of the present invention that when administered to a patient ameliorates a symptom of psychosis or schizophrenia. A therapeutically effective amount of a compound of the present invention can be easily determined by one skilled in the art by administering a quantity of a compound to a patient and observing the result. In addition, those skilled in the art are familiar with identifying patients having psychosis and schizophrenia and are readily able to identify patients who suffer from psychosis and schizophrenia.
The term "pharmaceutically acceptable salts, esters, amides, and prodrugs" as used herein refers to those carboxylate salts, amino acid addition salts, esters, amides, and prodrugs of the compounds of the present invention which are, within the scope of sound medical judgement, suitable for use in contact with the tissues of patients without undue toxicity, irritation, allergic response, and the like, commensurate with a reasonable benefit/risk ratio, and effective for their intended use, as well as the zwitterionic forms, where possible, of the compounds of the invention. The term "salts" refers to the relatively nontoxic, inorganic and organic acid addition salts of compounds of the present invention. These salts can be prepared in situ during the final isolation and purification of the compounds or by separately reacting the purified compound in its free base form with a suitable organic or inorganic acid and isolating the salt thus formed. Representative salts include the hydrobromide, hydrochloride, sulfate, bisulfate, nitrate, acetate, oxalate, valerate, oleate, palmitate, stearate, laurate, borate, benzoate, lactate, phosphate, tosylate, citrate, maleate, fumarate, succinate, tartrate, naphthylate mesylate, glucoheptonate, lactobionate and laurylsulphonate salts, and the like. These may include cations based on the alkali and alkaline earth metals, such as sodium, lithium, potassium, calcium, magnesium and the like, as well as nontoxic ammonium, quaternary ammonium, and amine cations including, but not limited to ammonium, tetramethylammonium, tetraethylammonium, methylamine, dimethylamine, trimethylamine, triethylamine, ethylamine, and the like. (See, for example, S. M. Berge, et al., "Pharmaceutical Salts," J. Pharm. Sci., 1977;66:1-19 which is incorporated herein by reference.)
Examples of pharmaceutically acceptable, nontoxic esters of the compounds of this invention include C 1 -C 6 alkyl esters wherein the alkyl group is a straight or branched chain. Acceptable esters also include C 5 -C 7 cycloalkyl esters as well as arylalkyl esters such as, but not limited to benzyl. C 1 -C 4 alkyl esters are preferred. Esters of the compounds of the present invention may be prepared according to conventional methods.
Examples of pharmaceutically acceptable, nontoxic amides of the compounds of this invention include amides derived from ammonia, primary C 1 -C 6 alkyl amines and secondary C 1 -C 6 dialkyl amines wherein the alkyl groups are straight or branched chain. In the case of secondary amines, the amine may also be in the form of a 5- or 6-membered heterocycle containing one nitrogen atom. Amides derived from ammonia, C 1 -C 3 alkyl primary amines and C 1 -C 2 dialkyl secondary amines are preferred. Amides of the compounds of the invention may be prepared according to conventional methods.
The term "prodrug" refers to compounds that are rapidly transformed in vivo to yield the parent compound of the above formula, for example, by hydrolysis in blood. A thorough discussion is provided in T. Higuchi and V. Stella, "Pro-drugs as Novel Delivery Systems," Vol. 14 of the A.C.S. Symposium Series, and in Bioreversible Carriers in Drug Design, ed. Edward B. Roche, American Pharmaceutical Association and Pergamon Press, 1987, both of which are incorporated herein by reference.
The compounds of the present invention can be administered to a patient alone or as part of a composition that contains other components such as excipients, diluents, and carriers, all of which are well-known in the art.
The compositions can be administered to humans and animals either orally, rectally, parenterally (intravenously, intramuscularly, or subcutaneously), intracisternally, intravaginally, intraperitoneally, intravesically, locally (powders, ointments or drops), or as a buccal or nasal spray.
Compositions suitable for parenteral injection may comprise physiologically acceptable sterile aqueous or nonaqueous solutions, dispersions, suspensions or emulsions and sterile powders for reconstitution into sterile injectable solutions or dispersions. Examples of suitable aqueous and nonaqueous carriers, diluents, solvents, or vehicles include water, ethanol, polyols (propyleneglycol, polyethyleneglycol, glycerol, and the like), suitable mixtures thereof, vegetable oils (such as olive oil), and injectable organic esters such as ethyl oleate. Proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersions and by the use of surfactants.
These compositions may also contain adjuvants such as preserving, wetting, emulsifying, and dispensing agents. Prevention of the action of microorganisms can be ensured by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, and the like. It may also be desirable to include isotonic agents, for example sugars, sodium chloride, and the like. Prolonged absorption of the injectable pharmaceutical form can be brought about by the use of agents delaying absorption, for example, aluminum monostearate and gelatin.
Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In such solid dosage forms, the active compound is admixed with at least one inert customary excipient (or carrier) such as sodium citrate or dicalcium phosphate or (a) fillers or extenders, as for example, starches, lactose, sucrose, glucose, mannitol, and silicic acid; (b) binders, as for example, carboxymethylcellulose, alignates, gelatin, polyvinylpyrrolidone, sucrose, and acacia; (c) humectants, as for example, glycerol; (d) disintegrating agents, as for example, agar--agar, calcium carbonate, potato or tapioca starch, alginic acid, certain complex silicates, and sodium carbonate; (e) solution retarders, as for example, paraffin; (f) absorption accelerators, as for example, quaternary ammonium compounds; (g) wetting agents, as for example, cetyl alcohol and glycerol monostearate; (h) adsorbents, as for example, kaolin and bentonite; and (i) lubricants, as for example, talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, or mixtures thereof. In the case of capsules, tablets, and pills, the dosage forms may also comprise buffering agents.
Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethyleneglycols, and the like.
Solid dosage forms such as tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells such as enteric coatings and others well-known in the art. They may contain opacifying agents and can also be of such composition that they release the active compound or compounds in a certain part of the intestinal tract in a delayed manner. Examples of embedding compositions which can be used are polymeric substances and waxes. The active compounds can also be in micro-encapsulated form, if appropriate, with one or more of the above-mentioned excipients.
Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups, and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art, such as water or other solvents, solubilizing agents and emulsifiers, as for example, ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propyleneglycol, 1,3-butyleneglycol, dimethylformamide, oils, in particular, cottonseed oil, groundnut oil, corn germ oil, olive oil, castor oil, and sesame oil, glycerol, tetrahydrofurfuryl alcohol, polyethyleneglycols and fatty acid esters of sorbitan or mixtures of these substances, and the like.
Besides such inert diluents, the composition can also include adjuvants, such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, and perfuming agents.
Suspensions, in addition to the active compounds, may contain suspending agents, as for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar--agar and tragacanth, or mixtures of these substances, and the like.
Compositions for rectal administrations are preferably suppositories which can be prepared by mixing the compounds of the present invention with suitable nonirritating excipients or carriers such as cocoa butter, polyethyleneglycol, or a suppository wax, which are solid at ordinary temperatures but liquid at body temperature and therefore, melt in the rectum or vaginal cavity and release the active component.
Dosage forms for topical administration of a compound of this invention include ointments, powders, sprays, and inhalants. The active component is admixed under sterile conditions with a physiologically acceptable carrier and any preservatives, buffers, or propellants as may be required. Ophthalmic formulations, eye ointments, powders, and solutions are also contemplated as being within the scope of this invention.
The compounds of the present invention can be administered to a patient at dosage levels in the range of about 0.1 to about 1,000 mg per day. For a normal human adult having a body weight of about 70 kilograms, a dosage in the range of about 0.01 to about 100 mg per kilogram of body weight per day is preferred. The specific dosage used, however, can vary. For example, the dosage can depend on a numbers of factors including the requirements of the patient, the severity of the condition being treated, and the pharmacological activity of the compound being used. The determination of optimum dosages for a particular patient is well-known to those skilled in the art.
In addition, the compounds of the present invention can exist in unsolvated as well as solvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of the present invention.
The compounds of the present invention can exist in different stereoisomeric forms by virtue of the presence of asymmetric centers in the compounds. It is contemplated that all stereoisomeric forms of the compounds, as well as mixtures thereof, including racemic mixtures, form part of this invention.
The following examples are intended to illustrate particular embodiments of the invention and are not intended to limit the scope of the disclosure or the claims in any manner.
EXAMPLES
The compounds of the present invention are prepared by the following methods, as illustrated in Schemes I and II. ##STR12##
Substituted heterocyclic phenols or thiophenols (2) are combined with dibromoalkanes (3) in acetone or 2-butanone at 50° C. to 80° C. for 8 to 48 hours in the presence of a base such as potassium carbonate or sodium carbonate to yield intermediate bromoalkyl ethers (4) (Scheme I). The reaction may also be performed in water at 50° C. to 100° C. with sodium hydroxide or potassium hydroxide as the base, in an alcohol solvent such as methanol or ethanol with sodium methoxide or sodium ethoxide as the base, or in a mixed water/organic solvent system under phase transfer conditions.
The bromoalkyl ethers (4) are reacted with substituted amines (5) in a solvent such as benzene, toluene, xylene, ethanol, acetonitrile, or N,N-dimethylformamide at 70° C. to 140° C. for 8 to 48 hours to yield the products (6). An additional molar equivalent of the amine (5) may be included in the reaction mixture in order to trap liberated hydrogen bromide, or an additional base such as sodium carbonate or potassium carbonate may be included for this purpose. Similarly, substituted alkyl bromides (7) (Scheme II) are reacted with substituted amines (5) to yield the products (8) under the reaction conditions used for the reaction of 4 with 5.
As starting materials, 2 and 7 are known or may be readily prepared by known methods. For the preparation of 2, see T. Harayama, et al., Heterocycles, 1994;39:613, and for the preparation of 7, see K. M. Jainamma and S. Sethna, J. Indian Chem. Soc., 1973;50:790. Similarly, 5 are known or may be readily prepared by known methods, such as J. Augstein, et al., J. Med. Chem., 1965;8:356 and G. S. Poindexter, Synthesis, 1981:541.
Example 1
6-(2-Bromo-ethoxy)-chromen-2-one
A mixture of 6-hydroxy-chromene-2-one, which can be synthesized in accordance with the procedure set forth by T. Harayama, K. Katsuno, H. Nishioka, M. Fujii, Y. Nishita, H. Ishii, and Y. Kaneko, Heterocycles, 1994;39:613, (3.2 g, 19.7 mmol), 1,2-dibromoethane (6.7 mL, 14.6 g, 78 mmol), and potassium carbonate (5.4 g, 39 mmol) in 150 mL of acetone is stirred at reflux for 48 hours. The cooled reaction mixture is added to 1.0 L of water and 250 mL of ethyl acetate. The mixture is filtered, and the insoluble material is washed with a small amount of additional ethyl acetate. The combined filtrates are separated, and the aqueous layer is washed several times with fresh ethyl acetate. The combined organic layers are washed with 5% aqueous sodium carbonate solution and brine, then dried (sodium sulfate), and evaporated. The residue is purified by flash chromatography (1% methanol in dichloromethane elution) to give 1.4 g (26%) of product. A sample recrystallized from ethyl acetate-hexane had melting point (mp) 101-102° C.
Example 2
6- 2-(3-Phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride
A mixture of 6-(2-bromo-ethoxy)-chromen-2-one (1.1 g, 4.1 mmol) and 3-phenoxy-1-propanamine, which can be synthesized in accordance with the procedure set forth by O. W. Lever, Jr., L. N. Bell, H. M. McGuire, and R. Ferone, J. Med. Chem., 1985;28:1870, (1.2 g, 7.9 mmol) in 15 mL of toluene is stirred at reflux for 48 hours. The precipitated solid is filtered and washed with toluene. The combined filtrates are evaporated to an oil residue. Purification of the oil by flash chromatography (8% methanol in dichloromethane elution) gives 0.30 g (22%) of the product free base as an oil. The oil is dissolved in 15 mL of dichloromethane, and the solution is treated with hydrogen chloride gas. The precipitated hydrochloride salt is filtered, washed with ether, and recrystallized from acetonitrile to give 0.24 g of product, mp 180-182° C.
Similarly prepared by the procedures of Examples 1 and 2 are:
(a) (3-Phenoxy-propyl)- 2-quinolin-6-yloxy)-ethyl!-amine hydrochloride, mp 208-210° C.
(b) 8- 2-(3-Phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride, mp 167-169° C.
(c) 7- 2-(3-Phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride, mp 203-205° C.
(d) 2-(Dibenzofuran-2-yloxy)-ethyl!-(3-phenoxypropyl)-amine hydrochloride, mp 238-240° C.
Example 3
4-Methyl-7- 2-(3-phenoxy-propylamino)-ethoxy!-chromen-2-one Hydrochloride
A mixture of 7-(2-bromo-ethoxy)-4-methyl-chromem-2-one, which can be synthesized in accordance with the procedure set forth by D. B. Shinde and M. S. Shingare, Asian J. Chem., 1994;6:265, (1.5 g, 5.3 mmol), 3-phenoxy-1-propanamine (0.72 g, 4.8 mmol), and potassium carbonate (0.72 g, 5.2 mmol) in 15 mL of N,N-dimethylformamide is heated at 90° C. for 16 hours. The cooled reaction mixture is filtered, and the filtrate is evaporated. The residue is dissolved in ether, and a small amount of methanol and the solution is treated with hydrogen chloride gas. The precipitated hydrochloride salt is filtered, washed with ether, and recrystallized from ethyl acetate-methanol to give 0.48 g (26%) of product, mp 195-196° C.
Similarly prepared by the procedures of Examples 1 and 3 are:
(a) 4-Methyl-6- 2-(3-phenoxy-propylamino)-ethoxy!-chromen-2-one hydrochloride, mp 205-206° C.
(b) 2-(Benzofuran-5-yloxy)-ethyl!-(3-phenoxy-propyl)-amine hydrochloride, mp 216-218° C.
Example 4
7- (2-Phenylamino-ethylamino)-methyl!-chromen-2-one
A mixture of 7-bromomethyl-chromen-2-one, which can be synthesized in accordance with the procedure set forth by K. M. Jainamma and S. Sethna, J. Indian Chem. Soc., 1973;50:790, (1.5 g, 6.3 mmol), N-phenylethylene-diamine (5.0 g, 37 mmol), and potassium carbonate (4.0 g, 29 mmol) in 200 mL of acetonitrile is stirred at reflux for 18 hours. The mixture is cooled and filtered, and the filtrate is evaporated. Purification of the residue by flash chromatography (10% 2-propanol in dichloromethane elution) followed by trituration of the product with ether gives 0.95 g (51%) of product, mp 91-92° C.
Similarly prepared by the procedure of Example 4 are:
(a) 7-{ 2-(3-Chloro-4-hydroxymethyl-phenylamino)-ethylamino!-methyl}-chromen-2-one, mp 175-176° C.
(b) 7-{ 2-(3,4-Dimethyl-phenylamino)-ethylamino!-methyl}-chromen-2-one, mp 92-95° C.
(c) 7- (2-p-Tolylamino-ethylamino)-methyl!-chromen-2-one, mp 90° C.-dec
(d) 7-{ 2-(3-Chloro-phenylamino)-ethylamino!-methyl}-chromen-2-one dihydrochloride, mp 273-275° C.
(e) 7-{ 2-(4-Chloro-phenylamino)-ethylamino!-methyl}-chromen-2-one, mp 99-100° C.
(f) 7-{ 2-(3-Chloro-4-methyl-phenylamino)-ethylamino!-methyl}-chromen-2-one, mp 77-78° C.
(g) 6- (2-Phenylamino-ethylamino)-methyl!-chromen-2-one, mp 95-99° C.
(h) 6-{ 2-(3-Chloro-4-methyl-phenylamino)-ethylamino!-methyl}-chromen-2-one hydrochloride, mp 200° C.-dec
(i) 7- (3-Phenylamino-propylamino)-methyl!-chromen-2-one, mp 68-69° C.
(j) 6- (2-Phenoxy-ethylamino)-methyl!-chromen-2-one hydrochloride, mp 196-198° C.
(k) 6- (2-p-Tolyloxy-ethylamino)-methyl!-chromen-2-one, mp 72-72° C.
(l) 6-{ 2-(4-Chloro-phenoxy)-ethylamino!-methyl}-chromen-2-one, mp 81-82° C.
(m) 7- (2-Phenoxy-ethylamino)-methyl!-chromen-2-one, mp 62-64° C.
(n) 7- (2-p-Tolyloxy-ethylamino)-methyl!-chromen-2-one, mp 90-91° C.
(o) 7-{ 2-(4-Chloro-phenoxy)-ethylamino!-methyl}-chromen-2-one, mp 89-90° C.
(p) 7- (2-Phenylsulfanyl-ethylamino)-methyl!-chromen-2-one hydrochloride, mp 279-280° C.
(q) 7- (3-Phenyl-propylamino)-methyl!-chromen-2-one, mp 70-71° C.
(r) 7-{ 3-(4-Chloro-phenoxy)-propylamino!-methyl}-chromen-2-one, mp 85-86° C.
(s) 7- (3-p-Tolyloxy-propylamino)-methyl!-chromen-2-one, mp 91-93° C.
(t) 6- (3-Phenoxy-propylamino)-methyl!-chromen-2-one, mp 81-83° C.
BIOLOGICAL METHODS
Cell Lines Expressing Dopamine Receptor Isoforms
A cell line expressing human dopamine D2 (Long form) receptors was purchased from Oregon Health Sciences University, Portland, Oreg. The D2 receptor cDNA was subcloned into an expression vector, pRc/CMV. The plasmids were transfected by electroporation into CHO K1 cells. A single stable transfectant, resistant to the antibiotic G418, was isolated and selected for use in the binding studies. For D4 binding, CHO K1 cells stably transfected to express the human recombinant dopamine D4.2 receptor subtype, as described by Shih, et al., "The expression and functional characterization of human dopamine D4.2 receptor in CHO K1 cells," Soc. Neurosci., 1995;21 (Part 1):621 were used.
Cell Culture and Preparation of Cell Membranes
CHO K1 cells expressing either human D2 and D4.2 receptors were grown in 162 cm 2 culture flasks in F12 medium (Gibco Laboratories, Grand Island, N.Y.) supplemented with 10% fetal bovine serum (FBS, Hyclone, Logan, Utah) in an atmosphere of 5% CO 2 /95% air at 37 EC. Cells were grown until confluent, after which growth medium was removed and replaced with 0.02% ethylene diamine tetracetate (EDTA) in a phosphate-buffered saline solution (Sigma Chemical Co., St. Louis, Mo.) and scraped from the flasks. The cells were centrifuged at about 1000×g for 10 minutes at 4° C. and then resuspended in TEM buffer (25 mM Tris-HCL, pH 7.4, 5 mM EDTA, and 6 mM MgCl 2 ) for D2 or the D4.2 buffer (50 mM Tris-HCl, pH 7.4, 5 mM EDTA, 1.5 mM CaCl 2 , 5 mM KCl, and 120 mM NaCl) and homogenized. The membranes were pelleted by centrifugation at 20000×g at 4° C. for 20 minutes. Then the pellets were resuspended in appropriate buffer at 1 mL/flask and stored at -70° C. until used in the receptor binding assay.
Receptor Binding Assays: D2, D4.2 Dopamine Receptors
A cell membrane preparation (400 μL) was incubated in triplicate with 50 μL 3 H!spiperone (0.2 nM for D2, 0.2 nM for D4.2), 50 μL buffer, or competing drugs where appropriate to give a final volume of 0.5 mL. After 60 minutes incubation at 25° C., the incubations were terminated by rapid filtration through Whatmann GF/B glass fibre filters (soaked for 1 hour in 0.5% polyethylenimine) on a cell harvester, with three washes of 1 mL ice-cold buffer. Individual filter disks containing the bound ligand were placed in counting vials with 4 mL of scintillation fluid (Ready Gel, Beckman Instrument, Inc., Fullerton, Calif.) and then counted in a Beckman LS-6800 liquid scintillation counter at an efficiency of 45%. Nonspecific binding was defined in presence of 1 mM of haloperidol.
Data Calculation
Saturation and competition binding data were analyzed using an iterative nonlinear least square curve-fitting Ligand program. In competition experiments, apparent K i values were calculated from IC 50 values by method of Cheng and Prusoff, "Relationship between the inhibition constant (K i ) and the concentration of inhibitor which causes 50% inhibition (IC 50 ) of an enzymatic reaction." Biochem. Pharmacol., 1973;22:3099-3108. Experimental compounds were made up as stock solutions in dimethyl sulfoxide (DMSO). The final concentration of 0.1% DMSO used in the incubation mixture had no effect on the specific binding. Each observation was carried out in triplicate. To allow these calculations, K d values were measured for the interaction of various ligands with the receptor. These were: 3 H!spiperone binding, human D2, 0.116+0.01 and human D4.2, 0.093+0.005 nM (n=3). The test results are presented below.
______________________________________Biological DataExampleNumber D4, K.sub.i (nM) D2, K.sub.i (nM)______________________________________2a 12.8 5782b2c 1.6 2492d 78.7 --3 1.9 2313a 70.2 --3b 1.2 5024 5.8 29204a 95 --4b 21 --4c 10 20874d 42 --4e 14 6964f 16 58824g 311 --4h4i 31 --4j 64 --4k 23.8 58824l 13.5 48704m 43 --4n 3.9 1954o 9.5 2864p 394 --4q 60 --4r 92 --4s 234 --4t 20 1066______________________________________
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This invention relates to compounds that are antagonists of dopamine D4 receptors, and to methods of treating psychosis and schizophrenia using a compound that is an antagonist of dopamine D4 receptors.
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This is a continuation of application Ser. No. 632,499, filed on Nov. 17, 1975, now abandoned.
BACKGROUND OF THE INVENTION
My invention relates to a series of elements consisting of articles with a mutual relationship and dimensioned according to standard sizes, which starting from an initial value, constitute a sequence. Such a series of elements is e.g. used in the building industry where within the scope of the industrialisation it has been tried to realize a so-called modular coordination.
A problem which occurs with a modular normalization is the great extent of liberty in designing buildings or interiors which one wants to maintain in general. This trend towards a modular normalization has on paper been successful to a degree and an example thereof is the S.A.R. designing method. (S.A.R. is a Netherlands Foundation for Architectural Research).
On realizing this system it has been found in practice that the manufacturer must choose between the fabrication of a plurality of panel sizes for bridging differences in size which arise, or that a plurality of fitting pieces should be held in store. A further considerable drawback of the methods performed consists of the inevitable loss consisting of sawed off pieces which cannot be used in the existing sequence.
SUMMARY OF THE INVENTION
My invention aims to provide a series of elements corresponding with a range of sizes which per article can be selected on their functional grounds that is to say grounds of applicability. According to my invention the size of the elements constitutes a series of the FIBONACCI type with an interrelation of 1/2 ± 1/2 √0.5.
From the arithmetical angle this "series" can also be considered as a progression since each size appears to have a value which is equal to the sum of the two preceding sizes.
As the interrelation of the sizes is approximately equal to 1/2 ± 1/2 √5 not only the number of possibilities of combination increases, but also the interval between the terms decreases. The advantages of such a series of elements with respect to production lies in the fact that with a very limited number of sizes one has an almost unrestricted possibility of combination. As a consequence of the aforementioned summation ability the sawing- or cutting loss is reduced to a minimum, since each sawing- or cutting rest constitutes again a new smaller size of said same series, which size can be used again.
The series of elements according to my invention is particularly distinguished in that the starting value of the series is constituted by a standard size which has a particular plate in the series. This particular place may be a smallest or greatest applicable value but may also be constituted by an intermediate size of the series, whereby then a part of the series has a smaller value (factor 1/2 - 1/2 √5) and the other part consists of one or more greater sizes (factor 1/2 + 1/2 √5).
It should be noted that the selection of the starting size or the sizes from the series can be determined from different standpoints, for instance on the base of function, size of material, production method or transport. Obviously other considerations are also possible. This choice is made according to whether the practicableness or the profit earning ability of the project concerned is the most decisive factor. This results in that for a complete project one can start in designing already from a standard itemization per product, a standared production series or process or a functional approach of the size by a well founded selection of the sizes of the base series and the length thereof. It should be noted that evidently not always a complete series need be selected. Since all sizes due to the summation ability can be composed from each other there are no compelling reasons to produce all sizes.
My invention relates particularly to a series of elements used e.g. in arranging a kitchen. Such a use lends itself particularly for normalization and standardization. According to my invention the starting value of the series is constituted by a measure of length of 60.3 cm while the descending part of the series recedes to 5.4 cm, whereby only six standard sizes are required.
In such a system there is therefore a very limited number of parts required which also simplifies the storage problem. Every composite size can also be immediately supplied, since it consists of two or more preceding sizes. On elaborating this system it appears that not only when a higher starting value is used but also with the group of lower values, one obtains an interval between two series, which is smaller than the smallest selected size. This implicates directly a connection with the itemization of the product. E.g. one selects a size series for house front elements. Now a window frame itemization could be selected in the same series at a lower level.
SURVEY OF THE DRAWINGS
FIG. 1 is a perspective view of the interior of a kitchen;
FIG. 2 illustrates a group of panels for an inner wall system to be manufactured.
DESCRIPTION OF PREFERRED EMBODIMENTS
In designing a module system for arranging a kitchen the starting point may be a size in the value of 60.3 cm. The preceding value is obtained by multiplication with the factor 1/2 - 1/2 √5, that is to say the factor 0,618, so that the size 37.3 cm is obtained. Further descending the values 23.0, 14.3, 8.7 and 5.4 cm are obtained. These sizes can be considered as the basic dimensions for the arrangement of a kitchen.
When e.g. free space of slightly less than 60.3 cm is available, e.g. 55.2 cm, then this space can be filled with an element sized 37.3 cm in combination with an element of 14.3 cm, whereby then only a free space of 3.6 cm is left. If a space of 60.3 cm is indeed available then an element of this size can be disposed therein in conformity with the two preceding values of the series viz. an element of 37.3 cm (e.g. a chest of drawers) and an element of 23.0 (e.g. a towel drier).
The series of elements according to the invention can be used both in the vertical direction and in the horizontal plane. On ergonomic considerations there are particular fixed values like the height of the dresser, the space between the dresser and the boxes disposed over the dresser, the greatest heights of the boxes and the ceiling height. In the system according to my invention cabinets may be added in order to attain the desired dresser height. When there is a ground clearance or plinth of 10.3 cm and a dishwasher is installed then an element with the greatest value (60.3 cm) can be used with a chest with a drawer height of 14.3 cm disposed thereon, together with a thickness of the slab of the dresser of 5.4 cm, so that a total value of almost 90 cm, that is to say the most advantageous height is obtained.
From the underside of the dresser slab there is measured 60.3 cm in an upward direction in order to reach the underside of the boxes above the dresser. In this way it is possible to align these boxes correctly with the elements provided along the other walls of the kitchen.
Usually these hanging boxes consist of two boxes placed on one the other, the lower one having a height of 60.3 cm and the upper one having a height of 37.3 cm. The top level of these boxes then lies at about 240 cm which is an acceptable ceiling height for a kitchen. The series can progress in greater sizes by using the factor 1/2 + 1/2 √5. Starting from 60.3 cm one obtains then 97.6 and 157.9. The latter size is used for a cabinet from the interior according to FIG. 1.
My invention can likewise be applied to another field of technics and an example thereof is the inner wall panel system according to FIG. 2.
The sizes can be formed from a material the thickness of which constitutes the series size of 7.3 cm. This means for production- and/or panel sizes 7.3; 11.9; 19.2; 31.1; 50.3; 81.4; 131.7; and 213.1 cm. By incorporating the thickness of material into the series, the solutions for the corners are simplified. It is advisable to carry out the details in the smaller terms of the same series. The aforementioned sizes need not relate only to the panel sizes to be produced (see figure) but may also relate to a sawing piece- or material size. The combination and exchangeability is identical to that of the kitchen elements. Due to the plan in the size system a standard itemization for the panel couplings both in the horizontal and the vertical sense can be arranged.
Other fields on which the series of elements according to my invention can be advantageously used are: containers, packings, cans and do-it-self shops. There, too, elements which are capable of being summed are usable and so loss of space is avoided, or storage space saved.
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A plurality of elements with dimensions forming a series of the FIBONACCI-type having a relationship of 1/2 ± 1/2 √5. Such elements are suitable for economizing storage space and manufacturing costs as only a limited number of different sizes are to be kept in stock.
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REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part of U.S. patent application Ser. No. 08/937,934, filed Sep. 25, 1997, now U.S. Pat. No. 6,064,065 entitled METHODS OF MINIMIZING SCATTERING AND IMPROVING TISSUE SAMPLING IN NON-INVASIVE TESTING AND IMAGING, which is a divisional of U.S. patent application Ser. No. 08/479,955, filed on Jun. 7, 1995, entitled METHODS OF MINIMIZING SCATTERING AND IMPROVING TISSUE SAMPLING IN NON-INVASIVE TESTING AND IMAGING, now United States Patent No. 5,672,875, which is a continuation-in-part of U.S. patent application Ser. No. 08/333,758, entitled RAPID NON-INVASIVE OPTICAL ANALYSIS USING BROAD BANDPASS SPECTRAL PROCESSING, filed Nov. 3, 1994, now U.S. Pat. No. 5,818,048, which is itself a continuation-in-part of U.S. patent application Ser. No. 08/182,572, entitled NON-INVASIVE NON-SPECTROPHOTOMETRIC INFRARED MEASUREMENT OF BLOOD ANALYTE CONCENTRATIONS filed Jan. 14, 1994, now U.S. Pat. No. 5,424,545, which is a continuation-in-part of U.S. patent application Ser. No. 08/130,257, entitled IMPROVEMENTS IN NON-SPECTROPHOTOMETRIC MEASUREMENT OF ANALYTE CONCENTRATIONS AND OPTICAL PROPERTIES OF OBJECTS, filed Oct. 1, 1993, now U.S. Pat. No. 5,434,412, which is a continuation-in-part of U.S. patent application Ser. No. 07/914,265, entitled NON-INVASIVE TESTING, filed Jul. 15, 1992, now U.S. Pat. No. 5,321,265. Disclosures of all the preceding applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to the use of radiation, preferably near-infrared radiation to detect and measure the concentration of constituents or other properties of interest of a material. More particularly, apparatus and methods have been developed for measurement of the concentration of constituents such as hemoglobin and its variants and derivatives, glucose, cholesterol and its combined forms, drugs of abuse, and other analytes of clinical and diagnostic significance in a non-invasive manner.
Because the apparatus developed for use of this method does not require the withdrawal of blood in order to perform these measurements, it is particularly suitable for testing in the home on a chronic basis such as for glucose levels in diabetics and for kidney function, e.g., urea or creatinine testing, in patients undergoing home dialysis. The present invention uses a variety of methods to change the pathlength through tissue and/or the blood volume within an optically sampled tissue to help distinguish the desired signal produced by one or more components of the blood volume from background noise produced by tissue or other components of the blood volume and from the background noise of the system itself.
The development of clinical testing procedures that do not require the withdrawal of blood has become an important goal due to the spread of AIDS and the associated fears among the public and health care personnel. Along with AIDS, other diseases, such as hepatitis, can be spread through the use of invasive procedures without stringent precautions to assure sterility. “Nosocomial transmission of hepatitis B virus associated with the use of a spring-loaded finger-stick device,” New England Journal of Medicine. 326(1 1), 721-725 (1992), disclosed a hepatitis mini-epidemic in a hospital caused by the improper use of an instrument for obtaining blood samples. The article describes how the hospital personnel unintentionally transmitted the virus from patient to patient by misuse of the sampling device. Such transfers, potentially hazardous to health care personnel as well as to patients, are eliminated by the non-invasive testing method performed by the apparatus and method of the invention.
Non-invasive testing will become particularly effective in the long-term management of diabetes. Improperly controlled glucose levels in diabetics can result in damage to the circulatory system, the nervous system, the retina and other organs. This damage can be largely eliminated by more effective control of glucose levels. However, this level of control requires the measurement of glucose levels four or more times a day. With current apparatus and methods, a painful finger prick is required for each such measurement. Furthermore, that part of the apparatus that contacts the blood to produce the required chemical change used in the measurement is disposed of after each measurement. The cost of these disposables can run thousands of dollars per year. The inconvenience and discomfort of glucose measurement exacts a further psychological toll from the diabetic. Finally, because the sampling process is conducted by relatively untrained personnel, it is prone to error. These errors have been reported to be as high as three to five times the inherent error in the process. Errors in the sampling process can occur either as a result of failure to obtain a proper blood sample (e.g., the sample may be an admixture of intracellular or interstitial fluid or blood) or failure to correctly apply the sample to the disposable part of the apparatus, or both.
These deficiencies in currently available apparatus and methods have caused a number of groups to attempt to develop devices for non-invasively measuring concentrations of various blood constituents. The most commercially successful devices for the non-invasive measurement of chemical constituents of blood are those that use “pulse oximetry” to measure the relative concentrations of oxyhemoglobin and deoxyhemoglobin. Because these two constituents are both highly absorptive in the near infrared and because of their crossing broadband features, the ratio of radiation intensities at two wavelengths can provide the requisite information. Based in part on the success of hemoglobin ratio measurements, much current work on non-invasive concentration measurements for chemical constituents of blood has also used the near-infrared region of the electromagnetic spectrum. Because of the number of diabetics most of this research is directed to techniques for the non-invasive measurement of blood glucose levels. Although glucose is present in low concentration, and although glucose has low absorptivity, the wavelength band between 700 nm and 1100 nm contains the third overtones of the glucose absorption spectrum. This band theoretically allows minimization of interference due to water absorption and exhibits good penetration of human tissue. Other promising research has used longer wavelengths, from 1100 nm to about 2500 nm.
Substantially all of this work has been carried out using variants on classic spectrophotometric methods. Classical methods typically use detectors which measure the radiation transmitted through or reflected from the sample in a relatively narrow wavelength passband. The passband is kept narrow for several reasons. First, a narrow passband reduces the practical deviations that can occur relative to the theoretical relationships between constituent concentration and absorbance. Second, a narrow detector passband allows better measurement of sharply peaked spectra by providing a measurement closer to the spectral peak of the constituent of interest. According to classical methods, this improves specificity, and for full-spectrum measurements, provides a more faithful rendition of the absorbance or reflectance spectrum.
The wavelength passband within which the detector operates can either be a property of the source or can be obtained by placement of an appropriate filter between the source and the sample, between the sample and the detector, or both. The width of the passband in classic spectrophotometry is ordinarily chosen to be small relative to the width of the spectral features of the constituent of interest and of the sample. Typically, a passband half-width of less than 10% of the spectral half-width is recommended.
In some spectrophotometric devices, the source is designed to scan the spectral region of interest so that the measured wavelength varies with time in a controlled manner. In other cases, the source is transformed into a coded broadband source whose interaction with the sample is later decomposed into narrow-band responses.
In most classic spectrophotometric devices and methods, the measured data is initially in the form of an uncorrected intensity versus wavelength. The next important step, performed within the spectrophotometric apparatus, is a logarithmic conversion of the data into absorbance or reflectance units using some reference intensity versus wavelength data for normalization. Extensive data processing of the transformed data is then employed in an attempt to isolate the components of the data arising from the constituent(s) of interest from the components arising from the background (due to constituents that are not of interest and instrumental artifacts). Many techniques are available for this isolation, virtually all of which are based on statistical regression techniques. Examples of this general approach include the works of Rosenthal, U.S. Pat. No. 5,023,737, and of Clarke, U.S. Pat. No. 5,054,487.
All of these classical spectrophotometric methods essentially search for a unique response or pattern of responses due to the constituent of interest at one or more specific wavelengths (or narrow wavelength passbands) and then attempt to separate these effects from the effects due to background constituents at those same narrow wavelength passbands. However, glucose and many other constituents of interest possess only weak broadband spectral features in the wavelength ranges of interest. Furthermore, the measurement environment is generally a mixture containing glucose and many other constituents having overlapping but different broadband spectral structures several of which, including water and the hemoglobin species, are strong absorbers in the wavelength ranges of interest. In non-invasive clinical measurements, these problems are further compounded by the presence of multiple diffuse radiation scattering centers in the tissue. As a result, the overall measurement environment is not conducive to the use of classical spectrophotometric techniques.
U.S. Pat. No. 5,321,265 (the “Block '265 patent”) discloses a system having a plurality of filters with overlapping passbands analogous to the overlapping passbands of the human eye's photoreceptors. The disclosed methods and devices use a broadband radiation source to illuminate a sample held in a chamber. Radiation from the broadband source is passed through a plurality of spectrally overlapping filters before reaching the detectors. These detectors detect the radiation transmitted, reflected or emitted from the sample and thereby measure the sample's “color” in the region of the spectrum defined by the filter and detector responses. U.S. Pat. No. 5,434,412 (the “Sodickson '412 Patent”) and U.S. Pat. No. 5,424,545 (the “Block '545 Patent”) concern modifications to the basic devices and methods disclosed in Block '265 to achieve better results.
The present invention concerns additional methods and devices which may be employed toward the measurement of a sample's color in pulse oximetry, and in standard photometric and spectrophotometric measurements for in vivo systems. The methods and devices of the invention are all directed to the use of mechanical stimuli for improving the accuracy, sensitivity, and repeatability of non-invasive measurements of blood constituents such as glucose. This is achieved in the invention by the use of mechanical stimuli to increase the optical magnitude of normal cardiac pulses, to generate a change in volume either within the blood or within the extra-cellular and intra-cellular compartments of the tissue, or to provide an estimate of tissue scattering.
The use of mechanical stimuli to enhance the signal-to-background ratio in pulse oximetry is well known. First, the measurement of the pulsatile portion of the data segregates the response of the blood from the interfering background response of the tissue lying in the optical path. Second, since only the arterial component of blood volume changes with each pulse, pulsatile measurement further segregates the arterial blood response from the venous blood response. This is particularly significant in pulse oximetry since arterial blood is considerably more saturated with oxygen than venous blood.
The use of mechanical stimuli, in the form of direct pressure, has long been considered essential in the non-invasive measurement of blood pressure. Its use in pulse oximetry applications has been considered for a number of years. For example, Wood (see U.S. Pat. No. 2,706,927) suggests that signal characteristics might be improved by squeezing the earlobe to remove the blood and then restoring blood flow after the measurement. Similarly, Shiga and Suzaki (U.S. Pat. No. 4,927,264) suggest using a pressure of approximately diastolic pressure in pulse oximetry. Both groups however, used the pressure for measurement of hemoglobin ratios in venous blood only. In fact, Shiga et al. specifically made their arterial measurements without applied pressure. Many of the pulse oximetry instruments on the market (for example, Nellcor, Pleasanton, Calif.; Novametrix, Wallingford, Conn.) maintain mild, steady pressure on the skin near the measurement site. However, there is no active use of the applied pressure in generating improved data.
In other disclosures, Harjunmaa et al. see U.S. Pat. Nos. 5,178,142 and 5,183,042 and Mendelson et al. see U.S. Pat. No. 5,372,135 demonstrate the possibility of compressing tissue to either change the volume of venous blood in the tissue or to change the ratio of intracellular to extracellular fluid volume. However, none of these disclosures demonstrate active control over the cardiac pulse to generate a change in arterial blood volume with improved properties for use in generating improved photometric data, nor do they indicate the possibility of creating controllable pulsatile variations in tissue optical characteristics to improve the measurement of such characteristics. Finally, Kiani-Azarbayjany et al. (U.S. Pat. No. (5,638,816) discloses that a pressure-induced pulse, separate from that of the cardiac cycle, may be used to alter blood volume and thereby increase signal-to-background ratio. However, this disclosure does not disclose methods of applying constant pressure for amplifying the normal cardiac pulse, nor does it reveal the superior methods disclosed herein for inducing the non-cardiac pulse.
For in vivo measurement of materials which have a much lower concentration or which provide a much lower signal, such as glucose, the natural pulsatile modulation, which is much lower in amplitude than the total signal, may be so small as to be useless. This is particularly likely for classical spectrophotometric measurements which have very low signal-to-background ratios when the concentration of the constituent of interest is low.
Accordingly, an object of the invention is to provide methods of using controlled mechanical stimuli to improve the signal-to-background ratio of in vivo non-invasive optical measurement devices.
A further object of the invention is to utilize controlled mechanical stimuli to improve methods for measuring the concentrations of constituents in arterial blood non-invasively.
A still further object of the invention is to generate improved artificial pulses to obtain greater sensitivity in non-invasive optical measurements.
Another object of the invention is to provide a measure of tissue scattering at a measurement site.
These and other objects and features of the invention are achieved by the methods and apparatus described in the Summary of the Invention, the Detailed Description and the Drawing.
SUMMARY OF THE INVENTION
The subject invention relates to various methods by which variations of the optical properties of tissue can be controllably introduced or enhanced in order to provide an increased signal-to-background ratio for non-invasive measurements. The methods disclosed in the subject invention employ varying amounts, locations of application, and frequencies of application of various stimuli to the circulatory system and/or to the tissue of the body. Different, controllable responses to the stimuli from the circulatory system or from the tissue may be obtained. These responses, in turn, produce controllable variations in the pathlengths of optically active compartments within the tissue. The controllable variations in pathlength thereby produce controllable variations in optical responses to radiation traveling through the tissue, as measured by appropriately configured detectors, in such a manner as to provide detector signals with increased signal-to-background ratios upon proper processing of these signals. These methods use a variety of mechanical stimuli to achieve this improved ratio.
In all the embodiments, the measurement site is illuminated by the selected radiation. This radiation can be either transmitted through, reflected from, or transflected from the measurement site. The detected signal is then analyzed, using methods known in the art, to determine the concentration of the constituent of interest.
In one method embodying the invention, a constant mechanical pressure is applied in an amount between diastolic and systolic pressure, thereby enhancing the mechanical pulsatility of the arterial wall by reducing wall stress, while still allowing arterial flow. A site adjacent to the measurement site is optimal for application of this mechanical pressure. The application of said mechanical pressure substantially enhances the pulse relative to the magnitude of the normal cardiac pulse, thereby improving signal-to-background ratios.
In another embodiment of the invention, the applied mechanical pressure exceeds the systolic pressure generated by the heart. While said mechanical pressure is maintained, arterial and venous blood flow are both halted. The relaxation of the mechanical pressure distal to the site of the application of the mechanical pressure empties the arterial volume into the venous volume of the body part. This redistribution of blood away from the optical path causes an increase in transmission of the radiation through the measurement site. Then, upon removal of the applied mechanical pressure, the inrush of blood (called a blood bolus) into the body part and subsequent redistribution of the blood volume causes a reduction in transmission. These induced transmission pulses are significantly larger than those caused by the natural cardiac pulse or the enhanced cardiac pulse.
In yet another embodiment, mechanical forces are applied by altering the hydraulic pressure existing between the heart and the measurement site. Such an alteration will change the venous blood volume at that site. One easy way to provide this alteration is to move an extremity, such as an arm, so that it is above or below the heart. Measurement of radiation passing through the site before and after such a change thereby provides information segregating the venous optical absorption from that of the tissue.
In another embodiment, the application of a mechanical force is undertaken at the measurement site itself to compress the tissue, thereby driving some of the water from the site and modifying the pathlength at the site. This applied pressure can be used to standardize the sample, thereby eliminating a variable in the processing of data.
These and other embodiments are further elaborated in the Detailed Description and in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates the normal arterial pulse, measured by a blood pressure measurement;
FIG. 1B shows a photometric transmission measurement of the arterial pulse of FIG. 1A; and.
FIG. 2 illustrates an embodiment for practicing the invention by optimizing the magnitude of the arterial pulse by applying a constant mechanical pressure.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to methods of enhancing signal-to-background in non-invasive measurements of blood components. These methods are primarily focused on the application of a mechanical pressure or force at or near the measurement site. The application of the mechanical pressure changes the blood volume and/or the pathlegnth of measurement to increase the signal obtained from the interaction of incident radiation with the bold component of interest, or decrease the background which interferes with the measurement.
The arterial pressure pulse created by the beating of the heart in normal human subjects is illustrated in FIG. 1 A. The magnitude of the peak and the shape of the curve at a particular measurement site are both complex functions of the pumping action of the heart, the physical properties of the blood (such as density and viscosity), the physical dimensions and properties of the blood vessels, both proximal and distal to the measurement site, the physical dimensions and properties of the tissue surrounding the arterial blood vessel in which the pulse is being measured, and the location and method used to measure the pressure.
FIG. 1B, on the same time scale as FIG. 1A, shows the intensity of radiation transmitted through a tissue volume having one or more arterial vessels contained within it. For the purposes of this graph, the illuminating radiation is assumed to include those wavelengths in which the hemoglobin species are the dominant absorbers (i.e., 700-1200 nm) and the detector whose response is graphed is assumed to be responsive to radiation in that same region of the spectrum. It is generally believed that the similarity between the waveform of FIG. 1 B and the pressure waveform of FIG. 1A occurs because the modulation (decrease) in transmission arises from an increase in the optical pathlength through the arterial vessels produced by their expansion during the systolic phase of the pressure waveform. One basis for this assumption is that non-invasive pulse oximetry measurements based on this assumption correlate well with measurements made on in vitro blood samples.
FIG. 1B differs from FIG. 1A in that the percent modulation of the radiation waveform by the pressure waveform is significantly lower than the percent modulation of the pressure waveform itself. Typically, pulse pressure is about 40-50% of diastolic pressure (normal diastolic pressure=80 mm Hg, normal systolic pressure=diastolic pressure+pulse pressure=120 mm Hg), while the transmission peak is typically about 5% of the baseline transmission.
The lower amplitude of the optical modulation is produced by a combination of several factors. Primarily, this decrease in modulation compared to that of the pressure waveform is caused by the fact that the optical phenomena are modulated by the various optical pathlengths in the system, whereas the pressure waveform is transmitted to its sensor with very little loss. Among the factors attenuating the modulation of the optical waveform are the scattering and absorption by the tissue elements in the radiation path, and the additional absorption due to the hemoglobin in the venous blood volume of the tissue, which is not modulated by the cardiac pressure waveform.
Because the optical waveform is only weakly coupled to the pressure waveform, the signal available from the normal arterial pulse is ill-suited for non-invasive measurement of analytes in arterial blood other than the hemoglobin species, which are the dominant absorbing constituents in the blood's absorption spectrum between 700 and 1200 nm. In order to increase the amplitude of the optical pulse and thereby better quantify the concentration of the less absorbing arterial blood constituents, it is desirable to increase the magnitude of the arterial pulse.
In the non-invasive measurement of arterial blood pressure, it is well known that increasing the external pressure on a body part increases the pulse amplitude in the arterial blood pressure waveform. The arterial pressure waveform reaches a maximum when the external pressure is halfway between the resting diastolic (minimum) and systolic (maximum) blood pressure. This phenomenon, which has been explained (Drzewiecki, G. et al., Annals of Biomedical Engineering, 22, 89-96 (1994)) based on the change in wall stress in the artery produced by the external pressure, has been employed in commercial devices such as the Finapres (Ohmeda, Englewood, Colo.) and Dinamap (Johnson & Johnson, New Brunswick, N.J.) for non-invasive blood pressure measurement, according to the method first described by Peñaz (Proc. 10 th Intl. Conf. Med. Biol. Eng., 104, 1973). However, this phenomenon has not been recognized as having useful applications in the non-invasive measurement of arterial blood constituents.
Thus, in a first embodiment of the invention, shown in FIG. 2, a controllable pressurization device 10 exerts a specified pressure (exerted by presser 30 and measured, if necessary, by sensor 32 ) upon a body part 12 located proximate to or within the portion of the optical measurement path 16 between the radiation source 20 and detectors 22 lying within the tissue 14 . The pressurization device includes at least one component which may be located in contact with and transmitting the pressure to the measurement site. This component is transparent to the radiation wavelengths intended to interact with the measurement site so that radiation can be transmitted through it. In other, related embodiments, the pressurization device 10 is to be used near, rather than at, the measurement site. In this embodiment, pressurization device 10 need not have a transparent portion.
The optimum level of pressure to be exerted by the pressurization device 10 (the mean arterial pressure) can be determined at the tissue measurement site 14 by examining the optical waveforms 50 produced by the detectors 22 and choosing that pressure which maximizes the coupling between the arterial pressure waveform and the optical waveform. This allows the optimum pressure to be determined on an individual basis and also allows for temporal variations in systolic and/or diastolic blood pressure in an individual.
This configuration permits the use of any type of spectral or temporal distribution of the radiation entering the tissue from the source 20 or leaving the measurement site 14 through the optical path 16 and reaching the detectors 22 . Furthermore, this configuration does not restrict the nature or geometry of the optical path, except to require optically transparent components as necessary to carry the radiation into or out of the tissue.
In a preferred embodiment, however, the radiation is broadband and is detected using a plurality of detectors having overlapping frequency responses, as previously disclosed in Block U.S. Pat. No. 5,321,265. In a particularly preferred embodiment, the body part 12 is the last joint of a finger oriented with the finger nail facing away from the radiation source. Since the finger nail serves as a relatively rigid restriction to the propagation of the force created by the cardiac pressure pulse, the application of external pressure to this particular body part when oriented in the manner described can advantageously be unilateral.
In a second embodiment of the invention, the pressurization device 10 exerts a pressure in excess of the subject's natural systolic pressure on the appropriate body part 12 thereby stopping all blood flow through the pressurized region. Such a pressure may be maintained for several seconds at most locations without causing injury. During application of said pressure, the blood in the arteries distal to the site of the application of said pressure continues to flow throughout he capillaries and into the veins, where it is halted from returning to the heart by the applied pressure. The resulting redistribution of blood from the arteries to the veins creates an increase in optical transmission.
When the mechanical pressure is removed, blood immediately re-enters the area previously cut-off, at a flow rate higher than normal. This well-known phenomenon of reactive hyperemia is largely controlled by the autonomic nervous system and has as its purpose the removal of accumulated metabolic wastes from the region and the restoration of normal constituent concentrations in surrounding tissues. This blood inrush increases the blood volume at the measurement site, and cause a sharp decrease in optical transmission through the measurement site. With proper allowance for the changes in the various absorbing species induced by the metabolic changes in the region, these large changes in optical pathlength can be accounted for in the measurements. Furthermore, the large changes in blood volume induced by this method of applying pressure to the body part will also produce large changes in the optical scattering properties of the body part within the optical path. Note that the artificial pulse induced by the sudden release of applied pressure is generally several times larger than the normal cardiac pulse. The detrimental effect of these large changes in optical scattering properties can be reduced by the use, in this embodiment, of detectors having overlapping frequency responses as first disclosed in US Patent 5,321,565. The overlapping spectral sensitivities of the detectors used substantially minimize the effects of changes in the scattering coefficients of the tissue on the modulated signals. This permits the use of a larger blood bolus which in turn provides higher signal-to-background ratios in non-invasive measurements of blood constituent concentrations.
Other methods utilizing applied mechanical pressure are also capable of producing large modulations in the volume of blood, and are therefore useful in this embodiment of the invention. In a preferred example of such a method, a large, pulsatile modulation is achieved by the cyclic elevation and depression of a body part 12 relative to the level of the heart. For ease of mechanical manipulation, the preferred body part is part of a body extremity. Elevation and depression of the body extremity relative to the level of the heart alternately drains and fills the venous blood vessels therein. The change in blood volume caused by such draining and filling causes large changes in the absolute transmission of radiation through the body part 12 , and does so without the application of pressure thereon. By avoiding the application of pressure on the body part, this method avoids pressure induced changes in the scattering coefficient of the tissue 14 therein.
In another embodiment of this invention, the modulation required for increased sensitivity may be applied to the tissue itself. In this embodiment, the pressurization 10 applies a periodic pressure to a tissue site in such a manner as to cause deformation of the tissue either by the cyclic movement of extracellular or intracellular fluid into and out of the radiation path within the tissue or by the movement of tissue cellular components into or out of the radiation path. If the applied pressure causes fluid motion, then the required pulse modulated changes in an optical characteristic arise from changes in radiation absorption within the optical path 16 . However, if the applied pressure produces movement of tissue cellular components, these movements are more likely to cause changes in scattering characteristics within the optical path. Unlike the previously discussed embodiments, which either employ a constant pressure or employ a variable pressure which exceeds the systolic arterial pressure, in this embodiment of the invention, the applied pressure does not exceed the systolic arterial pressure. In order to create movement of fluids or tissue components within the tissue, the pressurization device 10 applies direct pressure on the measurement site 14 . Accordingly, in this embodiment, the pressurization device 10 includes a component transparent to the optical radiation, as disclosed above.
The cyclic movement of fluids or cellular components into and out of the optical path 16 will in turn produce a waveform in the radiation reaching the optical detectors 22 . If the optical path within the tissue includes arterial vessels, then this waveform will be superimposed on the optical variations produced by the arterial waveform. However, if there are no arterial vessels within the optical path, then the optical waveform produced by the applied pressure waveform will be the only waveform present. When this is the case, methods well known in the art can provide substantial improvement in signal processing capabilities. The case in which no arteries are in the optical path, is likely to occur when the detectors 22 measure radiation reflected from the tissue measurement site 14 . It is well known that under these circumstances, the entering radiation, especially at longer wavelengths (above 1000 nm), does not penetrate the tissue deeply enough to interact with the arterial vessels. Therefore, this embodiment of the invention is particularly useful when the use of longer wavelengths of radiation for the measurements of constituents is desirable.
In some situations, measurements of tissue scattering properties may be required to generate data for correcting the raw measurements made using the methods of this invention. Therefore, in another embodiment of the invention, the pressurization device 10 is modified by the addition of a displacement sensor 34 which allows tissue deformation to be controllably changed by the alteration of pressure applied by the presser 30 . In this configuration, the pressurization device 10 can produce and the sensor 34 can measure changes in tissue thickness that are small compared to the total thickness of the tissue within the optical path 16 . Because of the high compressibility of most tissues, the pressure required for such small changes is small compared to the pressure required to produce changes in the natural arterial pulse waveform. However, these small pressure variations can change the magnitude and baseline value of the measured optical waveform. It has been discovered that this change is produced almost entirely by changes in the optical pathlength through those components of tissue that are free of arterial blood. These changes in optical pathlength are produced by the reduction in the pathlength through the scattering components of the tissue and by the reduction in the quantity of venous blood remaining in the optical path. By measuring the optical waveform over a range of low applied pressures, it is possible to derive quantitative information regarding the amount of venous blood and the pathlength changes produced by the scattering elements within the tissue. This quantitative information can then be used, along with the other techniques disclosed in this invention, to produce more precise and accurate information about blood and tissue constituent concentrations.
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The invention relates to the enhancement of the signal-to-background ratio of a non-invasive measurement of the concentration of a blood constituent at a measurement site by applying an external pressure at a location near the measurement site. In one embodiment, sufficient pressure is applied proximate to a measurement site to stop blood flow. The pressure is then suddenly relased, thereby generating a blood bolus passing through the site. By illuminating the measurement site before and during the passage of the blood bolus and observing the interaction of the input radiation with the measurement site, the concentration of a blood constituent can be measured. In another embodiment, the venous pulse is occluded by applying a pressure midway between systolic and diastolic pressure. By illuminating the measurement site in the absence of a venous pulse, the signal-to-background ration can be enhanced and the concentration of a blood constituent can be measured.
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[0001] This application claims priority to U.S. Provisional Patent Application No. 61/299,880, filed on Jan. 29, 2010, titled COMPOSITIONS AND METHODS FOR CURING CONCRETE, the entire disclosure of which is, by this reference, hereby incorporated herein.
TECHNICAL FIELD
[0002] The present invention relates generally to compositions and methods for curing concrete and, more specifically, to compositions that hold moisture within concrete as the concrete cures, as well as to methods for retaining moisture within concrete as it cures. Specifically, the present invention includes compositions and methods in which a hardening and densifying agent is used in curing concrete, including, without limitation, concrete structures, such as slabs, pavement, runways and decks (e.g., bridges, parking structures, etc.).
BACKGROUND OF RELATED ART
[0003] Concrete typically includes cement, fly ash, and an aggregate (e.g., sand, limestone, gravel, etc.), among other possible components (e.g., chemical admixtures, etc.). When water is added to the cement, a chemical reaction known as “hydration” occurs between the cement and the water. The resulting cement gel or paste cures, or sets, to bind the other components of the concrete together. The longer the cement is exposed to water, the more complete and consistent (e.g., even) the hydration reaction throughout the concrete. Initially, the cement gel or paste is rigid, but not very strong. If water is removed from the cement gel or paste (e.g., by evaporation, etc.) before the cement gel or paste gains sufficient strength, the resulting structural changes to the concrete (e.g., shrinkage, etc.) may cause the cement and, thus, the concrete, to be undesirably porous, to crack, or to otherwise weaken. Accordingly, it is often desirable to maintain a suitable water, or moisture, content within fresh concrete until the cement gel or paste has had sufficient time to gain strength.
[0004] A number of techniques have been developed to maintain the moisture content of fresh concrete as the cement within the fresh concrete cures, or strengthens. One common technique involves trapping water within the fresh concrete by providing a moisture barrier on the exposed surfaces of the fresh concrete. Common moisture barriers include resinous (e.g., acrylic, etc.) concrete curing compositions. Unfortunately, many conventional resinous concrete curing compositions do not provide an aesthetically pleasing finished surface, and they are difficult to remove. Even so-called “self-dissipating” compositions, which typically degrade when exposed to ultraviolet (UV) radiation over long periods of time (e.g., 40 to 60 days or longer), leave finished concrete surfaces with aesthetically undesirable appearances and are difficult to remove when further surface treatment (e.g., hardening and densifying, polishing, application of sealers, etc.) is desired.
SUMMARY
[0005] The present invention includes compositions that may be used to retain moisture within fresh concrete as it cures to optimize curing of the concrete. For the sake of simplicity, the compositions of the present invention are referred to herein as being useful for curing concrete.
[0006] A composition suitable for curing concrete may include a hardening and densifying agent. Examples of such an agent include, but are not limited to, silicates. As used herein, silicates include polysilicates (e.g., alkali metal polysilicates, such as lithium polysilicate, sodium silicate, potassium silicate, etc.) and colloidal silicas. The ability of the hardening and densifying agent to reduce porosity in exposed surfaces of fresh concrete may, in effect, cause the fresh concrete to retain moisture for prolonged periods of time, which may enhance or even optimize curing of the fresh concrete.
[0007] In some embodiments, a composition of the present invention may consist of the hardening and densifying agent. In other embodiments, a composition may consist essentially of the hardening and densifying agent.
[0008] Other embodiments of compositions that are suitable for curing concrete in accordance with teachings of the present invention may include, or even consist essentially of, a hardening and densifying agent and a siliconate (e.g., a metal siliconate; an alkali metal siliconate, such as potassium methyl siliconate; etc.). In addition to hardening and densifying concrete, some siliconates are known to form polymeric films on surfaces to which they are applied. Such a polymeric film may enhance the ability of the hardening and densifying agent to trap moisture within fresh concrete.
[0009] Another embodiment of a composition of the present invention includes a temporary moisture sealing agent in addition to a hardening and densifying agent and, optionally, a siliconate. When such an embodiment of composition is applied to a surface of fresh concrete, the temporary moisture sealing agent forms a substantially confluent (i.e., substantially non-porous) film over the surface. A film formed by the temporary moisture sealing agent acts as a moisture barrier, preventing water from escaping the temporarily sealed surface on which the film has been formed. In some embodiments, a temporary moisture sealing agent may degrade within days (e.g., three days, seven days, 14 days, less than a month, etc.) of its application to a concrete surface, enabling self-dissipation or simplifying its removal from the surface, and enabling further treatment of the surface without any significant time delay after the concrete has sufficiently cured.
[0010] A composition that includes or consists essentially of any of the foregoing may also include one or more non-essential components. Without limiting the scope of the present invention, non-essential components may include pigments, surfactants and leveling agents.
[0011] Concrete curing systems that include separate components are also within the scope of the present invention. In some embodiments, such a concrete curing system may include one component that includes hardening and densifying agent and, optionally, a siliconate, while a separate component includes a temporary moisture sealing agent.
[0012] The present invention also includes various embodiments of methods for formulating and manufacturing compositions that may be used to cure concrete. In a manufacturing method, a hardening and densifying agent may be blended with one or more substances, such as a siliconate or a temporary moisture sealing agent, that will retain moisture within fresh concrete as the fresh concrete cures.
[0013] In addition, the present invention includes methods for curing concrete. Such a method includes applying a composition that includes a hardening and densifying agent to an exposed surface of the concrete. The hardening and densifying agent may be applied alone, or with one or more other substances that will retain moisture within the fresh concrete. As a non-limiting example, the hardening and densifying agent may be applied with a siliconate. As another example, the hardening and densifying agent may be applied with a temporary moisture sealing agent. In embodiments where the hardening and densifying agent is applied to a surface of fresh concrete along with another substance that retains material within the fresh concrete, application of the hardening and densifying agent may be effected before the other substance forms a film or barrier on the surface. In some embodiments, the hardening and densifying agent may be applied before the other substance, substantially concurrently with the other substance, or as part of the same composition as the other substance. In other embodiments, the hardening and densifying agent may be applied to the surface after the other substance, but before the other substance forms a barrier on the surface (e.g., polymerizes, agglomerates, etc.).
[0014] Other aspects, as well various other features and advantages of different aspects, of the present invention will become apparent to those of skill in the art through consideration of the ensuing description and the appended claims.
DETAILED DESCRIPTION
[0015] A composition that is suitable for preventing moisture from escaping fresh, curing concrete (i.e., for use in curing concrete) in accordance with teachings of the present invention, in various embodiments, includes a hardening and densifying agent. Some embodiments of such a composition further include a siliconate. In other embodiments, a composition of the present invention may additionally include a temporary moisture sealing agent.
[0016] The hardening and densifying agent of a composition of the present invention may comprise, consist essentially of or consist of a polysilicate. More specifically, the polysilicate may include a metal polysilicate. In even more specific embodiments, the metal polysilicate may comprise one or more alkali metal polysilicates, such as lithium polysilicate. The polysilicate may make up about 10% to about 20% of the total weight (i.e., w/w) of a composition of the present invention. These percentages are based upon the polysilicate-containing product used in the composition. As polysilicates are typically provided in liquid form, the percentages represent the amount of liquid, regardless of the solids content of that liquid, used in a composition of the present invention. In embodiments where LUDOX® lithium polysilicate is obtained from Grace Davison of Columbia, Md., the actual solids (i.e., lithium polysilicate) content of that product is about 20% solids, by weight (w/w), meaning that the actual lithium polysilicate content of a composition of the present invention is about 2% to about 4% of the total weight of the composition (i.e., about 10%×20% to about 20%×20%).
[0017] As an alternative to a polysilicate or mixture of polysilicates, the hardening and densifying agent of a composition that incorporates teachings of the present invention may include, consist essentially of or consist of a colloidal silica, such as a cationic amorphous silica. Like polysilicates, colloidal silicas are often obtained in liquid form. For example, the colloidal silica suspension available from Grace Davison as LUDOX® HSA has a silica content of 29.0% to 31.0%, by weight of the solution. Thus, a composition that includes that type of colloidal silica may have an actual colloidal silica content of about 2.9% w/w (i.e., about 10%×29.0%) to about 6.2% w/w (i.e., about 20%×31.0%).
[0018] Of course, compositions that include mixtures of different types of hardening and densifying agents, including different silicates, are also within the scope of the present invention.
[0019] In embodiments where a composition of the present invention includes a siliconate, the siliconate may comprise about 3% to about 6% of the weight of the composition. In some embodiments, the siliconate may comprise a metal siliconate. In more specific embodiments, the siliconate may comprise an alkali metal siliconate, such as potassium methyl siliconate. As an example, the potassium methyl siliconate of a composition of the present invention may comprise the “silane resin solution” available from Dow Corning Corporation of Midland, Mich., as XIAMETER® OFS 0777 SILICONATE. That solution has a solids content of 40% to 70% w/w. Thus, the actual potassium methyl siliconate solids may make up about 1.2% (i.e., about 3%×40%) to about 4.2% (i.e., about 6%×70%) of the weight of the composition. Silicates and other hardening and densifying agents may facilitate curing of concrete without the need for subsequent removal, or requiring only a minimal removal effort (e.g., spraying with water, light brushing, etc.).
[0020] The temporary moisture sealing agent of the curing compound may be selected and/or configured to remain in place for a few days, then be removed with little or no additional effort. eventually break down and dissipate once the fresh concrete has sufficiently cured. Examples of a temporary moisture sealing agent that may be used in various embodiments of compositions and methods that incorporate teachings of the present invention include, without limitation, materials that will degrade in a matter of days (e.g., three days, seven days, fourteen days, etc.). In some embodiments, such a material may include a wax, such as a paraffin wax, a polyethylene wax, a scale wax, or the like.
[0021] The temporary moisture sealing agent may be included in a composition in an amount that will enable it to form a substantially confluent film over a surface to which the composition is applied. In some embodiments, about 30% to about 60% of the weight of a composition may comprise a temporary moisture sealing agent. A specific, but non-limiting, example of a wax that may be used in a composition of the present invention is the paraffin wax available from Michelman, Inc., of Cincinnati, Ohio, as MICHEM® LUBE 743. That material has a solids content of 35% to 50%, which would equate to about 10.5% (i.e., about 30%×35%) to about 30% (i.e., about 60%×50%) of a composition of the present invention. In other embodiments, the temporary moisture sealing agent may comprise a scale wax, such as MICHEM® EMULSION 70750 or MICHEM® EMULSION 39235, both of which are available from Michelman, Inc.
[0022] A specific embodiment of a composition of the present invention includes (or may consist of) about 10% to about 20%, by weight, lithium polysilicate or colloidal silica; about 3% to about 6%, by weight, potassium methyl siliconate; and about 30% to about 60%, by weight, wax, with the balance (e.g., about 14% to about 69%, by weight) of the composition comprising water.
[0023] In other embodiments, a composition of the present invention may consist of a temporary moisture sealing agent, a hardening and densifying agent (e.g., a silicate and/or colloidal silica), and, optionally, water.
[0024] As an alternative to a wax, a variety of other membrane or film forming temporary moisture sealing agents may be used in a composition that incorporates teachings of the present invention. Non-limiting examples of other temporary moisture sealing agents include oils and oil based curing compounds, polyvinyl alcohol (PVA) based curing compounds, chlorinated rubber curing compounds, resin based curing compounds, and other materials and compounds that will form a temporary membrane or film over a surface of fresh concrete to seal moisture within the fresh concrete as it cures. Another embodiment of temporary moisture sealing agent includes water-soluble film-forming polymers, such as those described by U.S. Patent Application Publication 2009/0162540 of Golovkova, et al., the entire disclosure of which is, by this reference, hereby incorporated herein. Other materials, such as chloroparaffins, fatty acid triglycerides, alkyl sulfonic esters (e.g., phenols, cresoles, fatty acid esters, etc.), phthalates (e.g., dioctyl phthalate, dibutyl phthalate, benzyl butyl phthalate, etc.), polymers derived from glycerol, polymers derived from iso-cyanates or thio-cyanates (e.g., polyurethane, vegetable oil-extended polyurethane systems, moisture-curable polyurethane polymers, etc.). polymers derived from sulfur-containing reactants and polymers derived from silicon-containing reactants may be used as temporary moisture sealing agents.
[0025] In addition to the foregoing components, as well as various combinations thereof, one or more other components may also be included in a composition according to the present invention. Non-limiting examples of such components include surfactants. leveling agents and pigments. In embodiments where a hardening and densifying agent is mixed with a temporary moisture sealing agent, a surfactant may enable these two components to homogeneously or substantially homogeneously blend with one another. A leveling agent may facilitate spreading of a composition of the present invention over a surface of a substrate to be cured. A pigment may serve a variety of functions, including, without limitation, providing an identifier of the state of a substrate (e.g., an indicator that the substrate has not cured, etc.), light reflectance (e.g., when a white or other light colored pigment is used) and the like.
[0026] The present invention also includes methods for compounding a composition for use in curing concrete. In various embodiments, such a method includes providing a volume of water, blending at least one hardening and densifying agent into the volume of water, then blending at least one temporary moisture sealing agent into the volume of water. Blending may be effected using substances (e.g., the hardening and densifying agent and the temporary moisture sealing agent, etc.) that are already in solution (e.g., aqueous based substances, etc.).
[0027] In some embodiments, a siliconate or mixture of siliconates may be blended into the composition. The siliconate or siliconates may be added after the hardening and densifying agent has been mixed with the water and/or before the temporary moisture sealing agent is blended with the water and the hardening and densifying agent.
[0028] In a specific embodiment, a volume of water is provided that corresponds to about 14 percent to about 69 percent of a total weight of the desired finished composition. At least one hardening and densifying agent is then mixed into the volume of water, with the amount of the hardening and densifying agent being sufficient to comprise about 10 percent to about 20 percent of the total weight of finished composition. Thereafter, a sufficient amount of at least one siliconate may be blended into the mixture such that about three percent to about six percent of the total weight of the finished composition will comprise the at least one siliconate. Finally, at least one temporary moisture sealing agent is blended into the mixture. The amount of the temporary moisture sealing agent may be sufficient to comprise about 30 percent to about 60 percent of the total weight of the finished composition. The resulting composition may then be packaged, stored, and transported in any suitable manner known in the art.
[0029] In addition, the present invention includes methods for curing concrete. Such a method includes applying a composition that includes a hardening and densifying agent to an exposed surface of the concrete. The hardening and densifying agent may be applied alone, or with one or more other substances that will retain moisture within the fresh concrete. As a non-limiting example, the hardening and densifying agent may be applied with a siliconate. As another example, the hardening and densifying agent may be applied with a temporary moisture sealing agent. In embodiments where the hardening and densifying agent is applied to a surface of fresh concrete along with another substance that retains material within the fresh concrete, application of the hardening and densifying agent may be effected before the other substance forms a film or barrier on the surface. In some embodiments, the hardening and densifying agent may be applied before the other substance, substantially concurrently with the other substance, or as part of the same composition as the other substance. In other embodiments, the hardening and densifying agent may be applied to the surface after the other substance, but before the other substance forms a barrier on the surface (e.g., polymerizes, agglomerates, etc.).
[0030] As the hardening and densifying agent and the temporary moisture sealing agent may be applied separate, the present invention also includes concrete curing systems in which these components are separate from one another.
[0031] The ability of a composition or system of the present invention to retain moisture within fresh concrete were evaluated by a known technique—the ASTM C 156 (2005) test protocol from ASTM International. The ASTM C 156 (2005) is a test protocol titled “Water Retention by Liquid Membrane-Forming Curing Compounds for Concrete” that determines the ability of various compounds to prevent moisture from escaping fresh concrete. Generally, the tested composition was applied to finished surfaces of fresh concrete slabs and the weight loss of each sample was measured after a predetermined duration of time.
[0032] More specifically, “standard” mortar was mixed. “Standard” mortar includes ASTM C 150 Type I/II Portland cement, ASTM C 778 standard graded sand, and water. The water-to-cement ratio of the mixture was 0.4 and the sand-to-cement ratio of the mixture was 2.19. The average flow of the mixture, which was measured in accordance with the protocol set forth by ASTM C 87, was 40.
[0033] The mortar mixture was used to prepare three two inch thick square mortar specimens with 39.1 sq. in. top surfaces for the tested composition, and three more mortar specimens to serve as a control. The surface of each mortar specimen was steel troweled. The edges of each specimen were sealed with paraffin wax, providing a test surface with an area of about 36 sq. in.
[0034] Shortly after the edges were sealed, the test composition was applied, by brush, to the surfaces of three corresponding mortar specimens. The tested composition was applied to the surface of each of the three mortar specimens in an amount equivalent to one gallon per 400 sq. ft. Nothing was applied to the surfaces of the three mortar specimens that served as controls during the test. At this point, each mortar specimen was placed in a special controlled humidity chamber (with a temperature of 100°±2° F., a relative humidity of 32% ±2%, and a water evaporation rate of 2 gal./hour) and weighed. The mortar specimens were then permitted to cure in the chamber for another 72 hours, at which point the weight of each mortar specimen was again determined. The final weighing indicated the weight loss, due to water evaporation, of each mortar specimen. The three weight loss numbers corresponding to each control and the three weight loss numbers corresponding to each tested composition were averaged, and the data that corresponded to the tested composition was compared to the data that corresponded to the control. The tested composition performed well within the parameters set by the test. Specifically, the tested composition exhibited an average mass loss of 0.45 kg/m 2 (0.092 lb/ft 2 ), which is well within the 0.55 kg/m 2 (0.113 lb/ft 2 ) mass loss limit set by ASTM C 156 (2005), indicating that a composition that incorporates teachings of the present invention is suitable for use in curing concrete.
[0035] Although the foregoing description contains many specifics, these should not be construed as limiting the scope of the present invention, but merely as providing illustrations of some embodiments. Similarly, other embodiments of the invention may be devised which do not exceed the scope of the present invention. Features from different embodiments may be employed in combination. The scope of the invention is, therefore, indicated and limited only by the appended claims and their legal equivalents, rather than by the foregoing description. All additions, deletions and modifications to the invention as disclosed herein which fall within the meaning and scope of the claims are to be embraced thereby.
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A composition that may be used to retain moisture within fresh concrete as it cures to optimize the curing of the concrete may include one or more hardening and densifying agents and one or more temporary moisture sealing agents. Additionally such a composition may include a siliconate. The hardening and densifying agent of such a composition may penetrate the surface of fresh concrete to react with free lime, providing the fresh concrete with a strong surface. The temporary moisture sealing agent may form a moisture barrier on the surface of the fresh concrete to prevent moisture from escaping from the fresh concrete before the fresh concrete has sufficiently cured. The temporary moisture sealing agent may degrade within a matter of days, facilitating its removal from the surface of the concrete once the concrete has cured and enabling further treatment of the surface without undue delay.
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BACKGROUND OF THE INVENTION
Prior Art
The most pertinent prior art known to applicant is a conveyor assembly built by applicant's assignee that is substantially like the conveyor assembly herein shown and described, with one important exception. In a device of this kind, an endless chain carrying flights operates inside a trough having a cover thereover to keep out dust and moisture. The conveyor trough and cover are built in sections for convenience of assembly and an inlet is provided in the section next to the tail section. In conveyor assemblies of this kind it is desirable to use a wear plate under the conveyor. In the prior conveyor assembly the wear plate was also of a trough-shape except the side walls were far less in height than the side walls of the outside trough. That wear plate in the prior conveyor could not be removed without taking all the section covers off, disconnecting and taking off the inlet and removing the entire conveyor and flights and putting in the wear plate through the top of the outside trough. It was a most tedious, expensive and irksome job especially on a conveyor assembly that might be in excess of 200 feet in length. The length of conveyor varies of course depending upon the distance the grain is to be conveyed, and to remove the cover, the conveyor and its flights, and the inlet upon any length of conveyor is a time consuming and expensive proposition to replace a worn wear plate.
BRIEF SUMMARY OF THE INVENTION
The instant invention includes a wear plate that is flat and has a row of notches along each side edge to receive therein the side bolts which secure the outwardly extending flange on the side walls of the trough to the bottom of the trough. When the bolts on one side are removed, and those on the other side are loosened, the trough bottom is dropped as far as the loosening of the bolts on one side is concerned. The wear plate will of course drop to the bottom at an angle permitting the wear plate to be slid out from under the conveyor and over the bottom plate to be disposed of. A new wear plate may then be slid over the bottom of the trough the notches engaged over the loosened bolts, and then the removed bolts reinserted and all the bolts tightened thus holding the new wear plate in position. This operation for each section takes but a few minutes and it is not necessary to remove anything out of the trough except the liner plate that is to be replaced. The conveyor stays in place. The top stays on the trough. The intake is not removed but remains in place whereby considerable time and labor is saved in replacing a wear plate in any section or in all the sections of the conveyor trough.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a fragmentary perspective view of a conveyor assembly embodying the improvements of the instant invention;
FIG. 2 is an enlarged plan sectional view of the tail section, taken as substantially indicated by the section line II--II of FIG. 1;
FIG. 3 is a greatly enlarged vertical section taken substantially as indicated by the line III--III of FIG. 1;
FIG. 4 is an enlarged fragmentary plan section through the head section of the assembly taken substantially as indicated by the line IV--IV of FIG. 1;
FIG. 5 is a view of an elevation of the rear end of the tail section taken substantially as indicated by the arrow 5 of FIG. 2;
FIG. 6 is a fragmentary isometric view with parts broken away showing how the liner is attached to the bottom of the conveyor trough; and
FIG. 7 is a transverse sectional view through the lower portion of FIG. 3 illustrating the manner in which a used wear plate is removed and the new wear plate installed, the chain and a flight being left in supported position for purposes of clarity, and the angle of slope of the wear plate is exaggerated for the same reason.
DETAILED DESCRIPTION
In order to present an environment for the instant invention to better point out its advantages, it is necessary to herein describe a goodly portion of the prior art conveyor discussed hereinabove. The assembly, especially the trough, includes a head section 1, a tail section 2, and as many intermediate sections 3 as may be required to cover the conveying distance. Sections 3 are all alike except the one next to the tail section is provided with an inlet 4. As seen in FIG. 1 and also in FIG. 3 the sections at the ends thereof have outwardly extending flanges as indicated at 5 and so they may be bolted together by bolts 6. Since it is desirable to keep out dust and unexpected moisture when conveying grain, the sections are all provided with a cover 7 bolted down to the sections.
Inside the covered trough, an endless conveyor operates, which conveyor includes a chain 8 carrying a plurality of flights 9. The flights are preferably triangular in cross section as seen in FIG. 6 to more gently handle the grain. The head section 1 carries on its top a motor 10 which drives a pulley 11. With reference to FIG. 4 it will be seen that the chain passes around a drive sprocket 13 which is connected through speed reduction means 12 to the drive pulley 11. Another sprocket 14 is mounted in the tail section 2 on a shaft 15. Both sprockets 13 and 14 turn counterclockwise so that the return reach of the conveyor is above the load carrying reach of the conveyor. The conveyor discharges its load as it enters the head section 1 before it reaches the sprocket 13, this section 1 being virtually bottomless and moving grain may be discharged right through the bottom opening 16 into any suitable form of receiver as indicated 17 in FIG. 1. After a conveyor flight has dropped its load through the bottom of the head section 1 it passes around the sprocket 13 to make its return journey and passes between a pair of deflectors or guides 18-18 which prevent the flight 9 from catching on the edge of the head section, but on the contrary the flight will pass straight and easily into the next adjoining section 3. On the return journey, the chain and flights pass over a plurality of relatively large rollers 19 as seen at the top of FIG. 3 which are large enough to lessen friction and permit easy passing of the conveyor.
After the conveyor has fully been assembled in the covered trough, the slack in the working reach of the conveyor is taken up by means at the end of the tail section 2. These means include a relatively heavy steel plate 20 welded to the rear end of the section 2 and to which a pair of threaded rods 21--21 are connected to the ends extending beyond reach of the section. These rods are also connected to take up brackets 22--22 which are in turn connected to shaft and flange bearings 23--23 of the sprocket shaft 15. No slippage can occur when the threaded rods 21--21 are tightened and the pressure is minus bending stresses but only compression stress when the shaft 15 moves with the sprocket toward the bar 20.
Since the chain and flight on the working reach of the conveyor operate flatly against the under surface as seen clearly in FIG. 5 of the drawings, wear plates have been utilized to preserve the bottom of the trough. Preferably, these wear plates or liners have been steel plates of the type sold by United States Steel Corporation under the trademark COR-TEN which has a hard surface and less friction on the flights. But, nonetheless, these liners eventually need replacement, a few, or all. But heretofore such replacement necessitated the removal of the trough cover of the intake through the cover and the complete conveyor and flights so that the liners could be placed in through the top of the trough.
The instant invention effectively solves that difficulty with the use of a specially constructed liner 25 for each section except the head section which is bottomless. As seen in FIGS. 3, 6 and 7, this liner 25 is provided with a row of notches 26 preferably along each side edge thereof spaced in keeping with the bolts 27 which join flange of a side member, the liner 25, and the trough bottom 28, a notch 26 of the liner embracing a bolt 27.
When it becomes necessary to replace the liner or wear plate 25 with a new one, the liner may be removed from either side of the trough, depending upon which side of the trough there is the most feasible working conditions. Assuming that those conditions occur on the right hand side of the trough looking from the trough toward the head section 1, the bolts 27 connecting the side plate to the base 28 with the liner therebetween are removed entirely. The bolts 27 on the opposite side are loosened. This will permit the liner and trough bottom to assume the position seen in FIG. 7, these two parts pivoting downward as much as permited by the loosened bolts so that the liner or wear plate 25 may be slid off the bottom 28 underneath the conveyor as indicated in FIG. 7. All that is necessary then is to take the old wear plate 25 out for disposition and slide a new wear plate on top of the bottom 28 back into position with the notches 26 embracing the loosened bolts 27 and then the parts may be pushed upwardly into original position the bolts 27 that were loosened are tightened and the bolts that were removed are replaced and tightened and the new liner is positioned properly. In the same manner a liner can be positioned in the tail section 2 without interfering with the chains and flights and sprocket.
This expeditious and timesaving manner of replacing an old wear plate with a new wear plate in the section of the entire system or more sections or even all of them is highly important in connection with the financial upkeep of the system. The system is shut down for as short a time as possible and the replacement job is accomplished with very little labor and a comparatively small amount of time when compared with the removal of the trough top all the way through, the removal of the inlet core and the dismantling of the entire conveyor 14 and then the reassemblage of the conveyor system replacement of the top on the trough and affixing the inlet and connecting the same grain source. While replacement of the wear plates or liners may be necessary only after a long time of usage, when it becomes necessary the amount of time and labor saved is tremendous.
This manner of removal and replacement of a wear plate through the bottom of a closed trough and beneath the operating equipment in that trough apparently embodies a new method of replacing a liner or wear plate and the value of such a method is quite realistic.
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A grain handling flight conveyor assembly including a flight conveyor operating in a trough of rectangular cross section, said trough having a cover to make it dust and waterproof, and a wear liner on the bottom of said trough so constructed as to be replaceable without removing the cover and taking out the conveyor.
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FIELD OF THE INVENTION
The invention relates to a method for a real-time-capable computer-assisted continuous analysis of an image sequence containing a variable pose of an object composed of interconnected elements movable in relation to each other.
The invention specifically relates to the estimation of the positions and orientations of the trunk and extremities of a living person who moves during the image sequence, i.e. the estimation of a human body pose.
BACKGROUND OF THE INVENTION
The estimation of the human pose in three dimensions (3D) has been studied in a number of scientific papers. Some of these papers have focused on the reconstruction of the human pose from 2D data acquired by a conventional camera.
In Agarwal A and Triggs B, Recovering 3 D Human Pose from Monocular images ; IEEE Transactions on Pattern Analysis and Machine Intelligence, 28 (1) (2006) 44-58, the pose is obtained from shape descriptors of silhouettes of the human body.
The authors Rosales R and Sclaroff S of Inferring Body Pose without Tracking Body Parts ; Proceedings of Computer Vision and Pattern Recognition (2000) 721-727, map simple visual features of a segmented body onto a series of possible configurations of the body and identify the pose by the configuration which is most probable in view of the given visual features.
A further approach in Shakhnarovich G, Viola P and Darrell T, Fast Pose Estimation with Parameter - Sensitive Hashing , Proceedings of the International Conference on Computer Vision (2003) 750-757, uses a large data base of exemplary images of human poses and the authors use parameter-sensitive hashing functions by which the exemplary pose which is most similar to a given pose is searched in the data base.
A major disadvantage of all of the methods based on 2D data is that the segmentation of the person whose pose is to be estimated is difficult, in particular in scenes with a complex background. Last but not least, this is at the sacrifice of processing power and hence to speed.
Another problem of 2D images is the detection of extremities directed at the camera but hide part of the upper part of the body in the 2D projection. In such a situation, the extremities can no longer be detected in the silhouette and detection becomes time-consuming.
A pose estimation based on 3D data is described, for example, in Weik S and Liedtke C-E, Hierarchical 3 D Pose Estimation for Articulated Human Body Models from a Sequence of Volume Data ; Proc. of the International Workshop on Robot Vision (2001) 27-34. Here, the 3D volume of a person is acquired by means of a multi-camera configuration using the shape-from-silhouette method. Subsequently, a 2D projection of the volume is calculated by means of a virtual camera and a model of the human skeleton is adapted to this projection. To estimate the 3D pose, the model of the skeleton is then retransferred into the 3D space by inverting the 2D projection.
The disadvantages of the method of Weik and Liedtke are that the acquisition of the 3D volume has to be carried out within a special device having multiple cameras in front of a uniformly green background and the calculation of the 3D volume is a time-consuming technique.
A further approach for the calculation of a 3D skeleton model is to thin out volumetric data directly within the three-dimensional space [Palagyi K and Kuba A, A Parallel 3D 12- Subiteration Thinning Algorithm ; Graphical Models and Image Processing, 61 (4) (1999), 199-221]. The human pose can then be estimated by means of the skeleton model.
A method for pose estimation based on stereoscopy was published by Yang H-D and Lee S in Reconstructing 3 D Human Body Pose from Stereo Image Sequences Using Hierarchical Human Body Model Learning ; ICPR '06: Proceedings of the 18 th International Conference on Pattern Recognition (2006) 1004-1007. The authors introduce a hierarchical model of the human body. Both the silhouette and the depth information are used for a given photograph to find the pose with the best match in the data base.
A disadvantage of this approach is the technique of stereoscopy which involves a long processing time. In addition, stereoscopy provides reliable depth data only if the respective scene has a sufficient texture.
A pose estimation by means of a self-organizing map (SOM) is described by Winkler S, Wunsch P and Hirzinger G in A Feature Map Approach to Real - Time 3 D Object Pose Estimation from Single 2 D Perspective Views ; Mustererkennung 1997 (Proc. DAGM) (1997), 129-136.
A SOM is a special neural network which can be trained for a task. The SOM is used here to learn a map of a 64-dimensional feature space into the three-dimensional space of possible rotations of a rigid object. Artificially generated views of the rigid object are used as the training data. 2D color photographs of the object form the basis of the application of this method. Based on the color information, the object is localized within the images and is cut out. Subsequently, the image is processed by a Sobel operator which is responsive to sudden differences in contrast within the image, so-called edges, and high pixel values are allocated to respective regions. In contrast, pixel values close to zero are allocated to uniformly colored regions. Finally, an image of 8×8 pixels, whose 64 values correspond to the feature vector, is generated from this edge image by reducing the resolution. The SOM three-dimensionally maps the resulting feature vector onto one of 360 possible orientations.
The disadvantages of the method of Winkler et al include the fact that this method exclusively treats rigid objects and therefore cannot be used for the 3D estimation of the human pose. In addition, this method is essentially based on the extraction of edge information by means of the Sobel operator. In the case of persons who normally wear different clothes and are photographed in complex natural scenes under varying conditions of illumination, it can be assumed that a unique representation based on edge information is not possible.
Another alternative for pose estimation is based on time-of-flight (TOF) cameras. A 3D TOF camera does not only provide a brightness image as usual cameras do, but can additionally measure the distance from the object. The camera emits infrared light which is modulated sinusoidally. In each pixel, the phase shift between the emitted light and the light reflected from the object is measured. From this phase shift, the time of flight of the light and hence the distance of the camera from the object point can be calculated. A TOF camera provides a depth edge which is perfectly registered with a brightness image (often referred to as “amplitude presentation” in the TOF nomenclature). Therefore, it is an attractive sensor for a large number of applications in image processing. A TOF camera produces only a 2½-dimensional image of the scene but this is done at a high image rate and without needing any additional computing time.
In Zhu Y, Dariush B and Fujimura K, Controlled Human Pose Estimation from Depth Image Streams ; CVPRW '08 IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops (2008), 1-8, a number of anatomical landmarks is three-dimensionally traced over time. The pose of a movable human model is estimated from the three-dimensional positions of these landmarks. The model is in turn used to resolve ambiguities in the detection of the landmarks as well as to produce estimations of the position of undetected landmarks. The method of Zhu et al simulates basic conditions such as the maximum bending angles of the joints and the avoidance of the mutual penetration of various parts of the body, amongst other things. Despite the complexity of the model, the method runs at a frame rate of at least 10 frames per second.
However, as conventional video sequences have a frame rate of 25 Hz, a real-time-capable pose estimation at an appropriate frame rate would be desirable. It is, however, the general object of the invention to make image information (color values on pixels) interpretable for machines after they have been electronically recorded or translated. The estimation of human poses is a subfield of computer vision which basically has two problems:
(1) The pose has to be determined rapidly and has to be updated rapidly in the event of a change. Here, a video rate of 25 Hz is desirable. (2) The person whose pose is to be determined is usually not in an ideal environment but rather in front of an unknown or at least hardly controllable background.
In addition, the instrumentation expenditure for the solution of the task should not be too large. A common PC and a relatively simple camera configuration should be sufficient.
Well-known from prior art are TOF cameras which allow to solve the problem of the separation of foreground and background in a particularly simple manner. A TOF camera produces a 2.5-dimensional image (2 dimensions plus distance from the camera). Object points which are hidden by other object points along the line of sight of the camera cannot be detected. Of an object, only its front visible surface is available as an aggregate of points in the 3D space for inferring the pose of the 3D object.
In the above-mentioned paper of Weik S and Liedtke C-E, Hierarchical 3 D Pose Estimation for Articulatd Human Body Models from a Sequence of Volume Data ; Proc. of the International Workshop on Robot Vision, 2001, no TOF camera is used but not less than 16 electronic cameras are used and a monochromatic background is needed to three-dimensionally model a person by means of his or her silhouettes from different directions.
In the paper of Haker M, Böhme M, Martinetz T and Barth E, Deicitc gestures with a time - of - flight camera ; The 8 th International Gesture Workshop, Feb. 25-27, 2009, at the ZiF (Center for Interdisciplinary Research) at the Bielefeld University, Germany, a TOF camera is used to rapidly detect a person in front of an arbitrary background. However, the interpretation of the “pose” is almost rudimentary and they write, for example: “We find the head and hand using a simple but effective heuristic: The initial guess for the hand is the topmost pixel in the leftmost pixel column of the silhouette; the head is the topmost pixel in the tallest pixel column.”
In other words: No matter which part of the body is farthest to the right within the image, the machine regards that part as the right hand. Actually, the use of this very simple pose estimation requires that the person always holds his or her right arm clearly away from the body if he or she wants to command the machine by moving that hand, for example. The approach described here cannot use gestures such as arms folded in front of the body.
Finally, the article of Breuer P, Eckes C and Müller S, Hand Gesture Recognition with a Novel IR Time - of - Flight Range Camera—A Pilot Study ; Proceedings of the Mirage 2007, Computer Vision/Computer Graphics Collaboration Techniques and Applications, Rocquencourt, France, Mar. 28-30, 2007, pp 247-260, is intended to determine the pose of a human hand as rapidly and exactly as possible from an aggregate of points detected by a TOF camera. It uses an anatomical model of the hand, which is fit into a portion of the aggregate of points, which had been isolated in advance as representing the hand.
This paper determines seven degrees of freedom (3 coordinates, 3 angles of rotation, 1 scaling factor) to obtain the best possible fit (minimization of the cost function K). Here, the hand model itself is rigid and is not changed at any time. A rotation, for example, has an effect on all nodes of the hand model at the same time without shifting the model nodes in relation to each other.
The method described there might produce a good estimation of the person and of the twist of his or her hand within the 3D space. But as soon as the person to be estimated moves his or her fingers distinctly, the method would not work any longer without any problem.
BRIEF SUMMARY OF THE INVENTION
Just at this point, the present invention goes beyond the prior art. The present invention also uses a model which has to be fit into the aggregate of points representing the person. However, the (skeleton) model is simple and is at the same time flexible in itself. The model node positions themselves, and not only global shifts and twists in relation to the aggregate of points such as in D1, are the subject of the fitting procedure. In this case, the neighborhood structure of the nodes of the skeleton model is maintained throughout the fitting process so that particular nodes of the model necessarily represent the trunk, the head and the arms, respectively. The amazing result is that even movements of the arms in front of the body, in particular also the folding of the arms, can be detected clearly and in real time (at video frequency; cf. FIG. 4 of the description). The continuous updating of the node positions from the preceding images makes this complex movement detectable for the machine. In this case, the updating rule corresponds to that of a self-organizing map (SOM, standard algorithm of the neural network theory, which is also explained in detail in this application) which is integrated here for the first time into the task of the estimation of the pose of an object which is not rigid in itself in order to map its—unforeseeable—movements onto a record which can be processed by machines.
It is, therefore, the problem of the invention to provide a method for pose estimation by means of a TOF camera, which allows a continuous image analysis and pose calculation at at least 25 frames per second.
This problem is solved by a method having the features of the independent claim. The dependent claims relate to advantageous embodiments. The method for a real-time-capable computer-assisted analysis of an image sequence containing a variable pose of an object composed of interconnected elements movable in relation to each other, the frames of the image sequence having been recorded by a time-of-flight (TOF) camera so that they can be processed by a computer and having brightness and distance data as functions of pixel coordinates of the camera for each frame of the sequence, comprises the following steps: detecting the pixels of a frame, which map the object; calculating a three-dimensional (3D) aggregate of points within a virtual space, which represents that surface of the object which is visible for the camera, by calculated projection of object-mapping pixels into such a space, taking into account acquired data of a distance from the object; fitting a model of the object, which consists of nodes and edges, into the computer-generated 3D aggregate of points for the frame, the nodes representing a selection of elements of the object and the edges representing interconnections of these elements; iteratively updating all node positions by using a learning rule to train a self-organizing map with a predetermined number of randomly sampled points of the aggregate of points; repeating the steps (a) through (d) for each subsequent frame of the sequence, the result of step (e) of the preceding frame being used respectively for the fitting process in step (c); and finally, (f) determining the changing pose from positions of predetermined nodes of the model, which have been detected in at least representative frames of the image sequence. More specifically, this method combines the use of a TOF camera with the process of fitting a simplified skeleton model into a 3D aggregate of points, which represents the front side of the person to be estimated, this fitting process being able to be updated in a real-time-capable manner, because it is implemented by a learning algorithm for a SOM.
The advantage of the high speed of image segmentation by the TOF camera and the rapidly calculable SOM-updating rule allow a reliable pose estimation at up to 25 frames per second on a 2.0 GHz PC with only a minimum programming and computing expenditure.
Advantageously, the camera pixels onto which the object is mapped are determined by an image segmentation of the image sequence of the TOF camera. Further advantageously, two threshold values for brightness and depth data of the TOF camera are also determined for each frame and a contiguous region of camera pixels is identified, whose measurement data are larger than the brightness threshold value and less than the depth threshold value. These brightness data may then be advantageously evaluated in channels in the form of a histogram so that two accumulation points can be identified and the brightness threshold value is set in such a way that it is between the accumulation points.
The depth data may also be selected by using a depth threshold value in such a way that it [the depth threshold value] is between the accumulation point of the lowest depth and the other ones. Advantageously, the node positions of the model will in turn be updated in iteration steps, one point x being randomly sampled for the predetermined number of points of the 3D aggregate of points in each iteration step and all nodes being shifted towards x, the degree of the shift being largest for the node which had the smallest distance from x prior to the iteration step. To this end, the degree of the shift of all nodes is determined in such a way that it decreases with the number of iteration steps if required. The number of the randomly sampled points x or of the iteration steps is then 10% of the total number of the points within the aggregate of points, for example.
It is further advantageous that prior to each iteration step, for the first node having the smallest distance from the sampled point x, a second node is selected, which is a neighbor of the first node and whose distance from the first node does not exceed a predetermined value during the shift of the nodes.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail with reference to the drawings, where:
FIG. 1 illustrates an exemplary photograph of a test person, which was taken by a TOF camera. The upper image shows the amplitude data, the central one shows the depth map and the bottom one shows the resulting segmented image.
FIG. 2 illustrates the graph structure serving as a simple model of the human body. The edges define the neighborhoods of the SOM.
FIG. 3 illustrates the aggregate of points of scan points of the visible surface of a person in front of the camera. The graph structure represents the model for the estimation of the pose, which is put into the data by the SOM learning rule.
FIG. 4 is a selection of frames from a video sequence, which shows a sequence of gestures. The model by which the pose is estimated is drawn into each frame as a 2D projection. The edges of the model, which belong to the head and to the upper part of the body, are drawn in white, whereas the edges of the arms are shown in black.
DETAILED DESCRIPTION OF THE INVENTION
The first step of the method according to the invention is to separate (to segment) the human body from the background of the frame. To do so, a simple threshold method is used, which utilizes both the depth map and the amplitude presentation. The brightness and depth values recorded by the TOF camera are respectively entered in a histogram. The threshold values for the two frames are adaptively determined by means of the histograms for each frame as will be explained in the following.
In the case of the amplitude presentation (cf. at the top of FIG. 1 .), the pixel value corresponds with the light intensity of the active IR illumination of the TOF camera, which comes back from the scene into the camera. The amplitude presentation may also be regarded as a measure of confidence in the measured values of the depth map, as it is directly connected with the signal-to-noise ratio of the measurement. The attenuation of the amplitude is proportional to the squared distance of the object from the camera. Therefore, objects which are close to the camera usually appear markedly brighter than objects of the background.
To find an adaptive threshold value which separates the background from the foreground, the same is determined on the assumption that the histogram of the brightness values has exactly two essential maxima around which each of the numbers of brightness values follow approximately a Gaussian distribution. Under these circumstances, one speaks of a bimodal distribution, and the threshold value is selected in such a way that it separates the two distributions from each other as good as possible. A more precise segmentation on the basis of a threshold value for the amplitude presentation alone is generally difficult, as different objects may also have different reflecting characteristics for infrared light.
In the case of the depth map (in the middle of FIG. 1 ), the assumption of a bimodal distribution is broken in the histogram of the depth values if multiple objects exist at different distances in front of the camera. It is, therefore, assumed that each maximum in the histogram corresponds with an object if the objects actually exist at different distances in front of the camera. The threshold value used for the segmentation is determined as that one which separates the maximum of the object closest to the camera from the remaining maxima.
When the segmented amplitude presentation is combined with the segmented depth map for the final segmentation, only those pixels are regarded as ones of the foreground which had been allocated to the foreground both in the amplitude presentation and the depth map. That is, the intersection of all of those pixels is used, which are not excluded by one of the two threshold exceedances.
Preferably, the largest contiguous segment of foreground pixels is searched by means of methods known per se, and only pixels of this segment are finally allocated to the foreground, whereas all other pixels are regarded as belonging to the background. A result of such a segmentation is exemplarily shown at the bottom of FIG. 1 . This process step is useful for the segmentation if other objects or persons exist relatively closely behind the person to be estimated. If the target person stands evidently isolated and this fact is known, the search for contiguous segments may be skipped.
The identified foreground pixels may be regarded as representing scan points of the visible surface—of the front side—of the person in front of the camera.
As the intrinsic parameters of the camera such as focal length and size of the pixels are known, the process of imaging can be reversed by means of the depth values measured by the TOF camera. This allows the determination, for each pixel, of the 3D space coordinates of that point within the scene, which was mapped onto that pixel. For a pixel having the pixel coordinates (x, y) and the related depth value r, the relevant 3D space point x is obtained by means of the following formula:
x _ = r ( ( c x - x ) · s x , ( c y - y ) · s y , f ) T ( ( c x - x ) · s x , ( c y - y ) · s y , f ) T 2 ( 1 )
where (c x , c y ) denotes the pixel coordinates of that point at which the optical axis of the camera meets the image sensor. The parameters s χ and s γ indicate the height and depth of the pixels, respectively, and f is the focal length of the lens. The operator transposes a line vector and ∥·∥ 2 describes the Euclidian norm.
If the above formula is applied to all foreground pixels of the segmented image, a 3D aggregate of points is obtained, which represents the three-dimensional shape of the person in front of the camera.
This approach has two essential advantages:
(i) The presentation is scale-invariant, as the person in the three-dimensional space has always the same size, irrespective of his or her distance from the camera.
(ii) Parts of the body, which are extended in front of the upper part of the body towards the camera and partially hide it, may be easily found nevertheless due to the variation of the depth values. However, this piece of information gets lost in 2D projections of standard cameras, causing there much more complex problems.
In the second step of the method according to the invention, a simplified skeleton model is fit into the 3D aggregate of points, which represents the front side of the person to be estimated. In this case, the skeleton model preferably has a simple design and represents only those anatomical conditions of the human body, which are relevant to pose estimation.
FIG. 2 illustrates the model which is used here exemplarily. The model is described by a graph consisting of 44 nodes for the upper part of the body, the head and the arms. In this case, the anatomical construction of the body is described by the edges of the graph. For example, the arms are represented by chains of nodes connected in pairs by edges, whereas the upper part of the body is described by a two-dimensional grid. It will be apparent to persons skilled in the art that the concrete configuration of the skeleton model may be selected according to the frame to be evaluated and, therefore, this should not be regarded as limiting the invention. For example, the model may be expanded to the representation of legs without any problem, by adding, at the lower end, two other chains of nodes connected in pairs.
According to the invention, the skeleton model may also be regarded as a self-organizing map (SOM) and may be used accordingly.
Basically, a SOM represents an allocation of data points {right arrow over (x)}, which is implemented by a neural network, to the so-called codebook vectors {right arrow over (v)}. It is the aim to find an allocation which represents the input data, like in the case of vector quantization, with the smallest possible root-mean-square error. To do so, a SOM is trained by means of appropriate learning rules, which shifts the codebook vectors within the input space in such a way that the error is minimized.
As an expansion of the vector quantization, a neighborhood structure for the codebook vectors is given to the network. This neighborhood structure comes to fruition in each learning step which the network goes through: A training data point {right arrow over (x)} is randomly sampled and the codebook vector {right arrow over (v)}, which comes closest to it is determined. Now a learning rule is applied to the codebook vector {right arrow over (v)} * , which shifts this vector in the direction of the training data point {right arrow over (x)}. In addition, the neighbors of {right arrow over (v)} * , which are defined in the neighborhood structure, are also shifted in the direction of the training data point {right arrow over (x)}. This causes codebook vectors which are close to each other due to the neighborhood structure to be spatially close to each other also within the input space after the network has been trained. The codebook vectors are hereafter referred to as nodes.
The SOM having nodes and a neighborhood structure, which is used according to the invention, is also shown in FIG. 2 . The nodes are shown as points and the edges define the neighborhoods. Therefore, a node has as its neighbors all the nodes to which it is directly connected by an edge.
The SOM is trained by an iterative learning rule for each segmented frame of a video sequence on those pixels which have been allocated to the foreground in advance. For the first frame of a sequence, the pose from FIG. 2 , for example, serves as an initialization of the model. During the initialization, the model is shifted into the centroid of the 3D aggregate of points. At the beginning, the size of the model is adapted once to the size of the person in front of the camera. Once it has been selected correctly, it need not be adapted any further during the current process, as the method according to the invention is scale-invariant. In this case, the selection of the initial size of the model is not a particularly critical parameter and the method is not sensitive to relatively large variations during the initialization.
Each training UI all subsequent frames of the sequence is started with the model which has been learned in the preceding frame.
Each adaptation of the model to a new frame includes a complete training of the SOM, i.e. the model learns the structure of the 3D aggregate of points by means of the pattern-by-pattern learning rule where the learning rule is iteratively applied training data point by training data point each time. In this iterative method, data points {right arrow over (x)} are randomly sampled from the set of all training data and the model is adapted by means of the following learning rule:
{right arrow over (v)} * t+1 ={right arrow over (v)} * t +ε * t ·( {right arrow over (x)}−{right arrow over (v)} * t ) (2)
{right arrow over (v)} n t+1 ={right arrow over (v)} n t +ε n t ·( {right arrow over (x)}−{right arrow over (v)} n t ) (3),
where {right arrow over (v)} * denotes the node which is, in relation to a distance dimension d({right arrow over (x)},{right arrow over (y)}), closest to the training data point {right arrow over (x)}. As the distance dimension, the Euclidean standard
d ( {right arrow over (x)},{right arrow over (y)} )=∥ {right arrow over (x)}−{right arrow over (y)}∥ 2 =√{square root over (( {right arrow over (x)}−{right arrow over (y)} ) 2 )}
is used, for example. The nodes {right arrow over (v)} n represent the neighbors of the node {right arrow over (v)} * as is predetermined by the model of FIG. 2 . The values ε * t and ε n t represent the learning rates for the next node and its neighbors, respectively. In this case, the learning rate ε * t is selected as follows:
ε * t =ε i ·(ε f /ε i ) t/t max (4),
where t∈{0, . . . , t max } describes the current learning step for a frame and t max represents the maximum number of learning steps carried out in this frame. The initial learning rate ε i and the final learning rate ε f are exemplarily set to the values 0.1 and 0.05, respectively. The learning rate for the neighbors is set to ε n t =ε * t /2.
The use of this learning rule cannot always ensure that the neighborhood structure of the model in relation to the extremities, that is, the arms in this case, is maintained. The following example is intended for clarification: The hands of a person touch each other in front of the upper part of his or her body. If the hands are moved away from each other again, it may happen, for example, that the model uses the last node of the left arm to represent data points which actually belong to the right hand. Now this may result in the fact that the last node of the left model arm is continued to be attracted by points of the right hand, even though the hands have already moved farther away from each other. The left arm seems to extend through a part of the space in which no data points exist at all.
Basically, the learning rule of the SOM is able to solve this problem over the time. However, only a very small number of learning steps is carried out per frame to ensure a good running time, which may temporarily result in a wrong estimation of the pose.
To avoid this problem, the above-mentioned rules can be expanded in a simple manner so that the learning process in the scenario described will be successful more rapidly. This expansion prevents adjacent nodes from moving away farther than a predetermined distance from each other. This is achieved with the following rule, which is applied after the actual learning rules from equations (2) and (3) if the distance d({right arrow over (v)} * ,{right arrow over (v)} n a ) exceeds a predetermined threshold value φ:
v -> * = v -> n a + ϕ · ( v -> * - v -> n a ) v -> * - v -> n a 2 . , ( 5 )
where {right arrow over (v)} n a represents a definite neighbor of the node {right arrow over (v)} * , which is referred to as an anchor. The rule ensures that the distance between the node {right arrow over (v)} * and its anchor will never exceed φ. In this case, the threshold value φ depends on the scaling of the model. The anchor of the node is each time defined as that neighbor node which, in relation to the graph structure of the model, is on the shortest path on the way towards the center of the upper part of the body in the model, i.e. it is that neighbor node which is connected to the center of the upper part of the body by the least number of edges.
An exemplary estimation of the pose is shown in FIG. 3 . This figure shows the aggregate of points for the foreground pixels of the segmented image at the bottom of FIG. 1 . The model adapted to the data is drawn here into the aggregate of points. It can be seen that the model reflects the anatomy of the person correctly. For example, the upper part of the body is well covered by the two-dimensional grid, some bones extend into the head and the two one-dimensional chains of nodes follow the arms. Therefore, the positions of essential parts of the body such as the hands, for example, can be directly taken from the corresponding nodes of the 3D model.
Finally, FIG. 4 shows a number of gestures of a video sequence. Each of these frames shows the segmented amplitude presentation and the 2D projection of the model which was drawn in the presentation. The model is able to follow the arms even in difficult situations where the arms are folded closely in front of the upper part of the body. The model is also able to reliably estimate the position of the head, even though a large part of the head is hidden behind the arms in some frames.
An essential advantage of the method according to the invention is that the training of the model for each new frame is completed very rapidly. It could be determined empirically that only a very small amount of data from the 3D aggregate of points has to be used during the training, even if the person in front of the camera executes very fast movements. FIG. 3 contains approximately 6500 foreground pixels. However, only about t max =650 data points are randomly sampled and are used in a random order for the training of the SOM by the pattern-by-pattern learning rule. Therefore, the computing expenditure of the method is very small and the pose can be estimated at a frame rate of up to 25 frames per second on a 2.0 GHz PC.
Basically, the method according to the invention can be expanded to any kind of movable objects whose poses are to be estimated three-dimensionally. The combination of TOF camera data and the use of a SOM allows a simple and efficient implementation if there exist restricted movement opportunities for object elements, which can be simulated by a SOM having nodes and a neighborhood structure. This is particularly true if the objects to be estimated are known to have rigidly interconnected elements which are at the same time designed in such a way that they are movable in relation to each other. The human body is in the sense of the invention only one example of such an object.
In case of the estimation of the human pose, the method allows the real-time-capable detection of human gestures. First, the system directly allows the interpretation of pointing gestures, as the positions of the head and hand within the space are known. This allows to identify the direction in which pointing is done, by defining a beam along the hand, which originates from the head. This beam intuitively corresponds to the direction of pointing. If the space coordinates of the object at which pointing is done are additionally known, these may be used to exactly determine the area at which pointing is done. A presentation using PowerPoint slides may be used as an example, where a laser pointer is replaced with a virtual laser pointer, i.e. a red point is shown at that spot on the projected slides, at which the speaker points.
Second, the method according to the invention can be used to develop a system for the detection of more complex gestures on the basis of visual space-time features. The evaluation of such space-time features demands a high processing power of the system. If the positions of some landmarks such as the hands are known, the evaluation of the space-time features can be confined to just those regions in which the hands exist. In addition, the knowledge of the relative positions of the landmarks allows the detected space-time features to be put in relation to each other into a larger context, making the detection of the gestures more unique and hence reliable. A method configured in such a way is then able to detect complex gestures which may be used as an input into a computer-assisted system. Such systems may range from technical control systems in medical and industrial fields, information terminals and multimedia systems for home use to computer games.
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The invention relates to a method for the real-time-capable, computer-assisted analysis of an image sequence of an object consisting of elements that can be moved relative to each other and are interconnected, said sequence containing a variable pose, wherein the individual images of the image sequence are recorded by way of a time-of-flight (TOF) camera such that said images can be processed by a computer, and contain brightness and distance data as functions of the pixel coordinates of the camera for each image of the sequence, comprising the following steps: a. Capturing the pixels of an individual image forming the object, b. calculating a three-dimensional (3D) point cloud in a virtual space, said point cloud representing the surface of the object that is visible to the camera, by a computational projection of object-depicting pixels in such a space, while taking captured distance data to the object into consideration, c. fitting a model of the object consisting of nodes and edges into the computer-generated 3D point cloud for the individual images, wherein the nodes represent a selection of elements of the object and the edges represent the connections of said elements amount each other, d. iteratively updating all node positions by applying a learning rule for training a self-organizing map having a previously defined number of randomly selected dots of the point cloud, e. repeating steps a. to d. for each subsequent individual image of the sequence, wherein for the fitting in step c. the result of step e. of the preceding image is used in each case, and f. determining the varying pose from the positions of predetermined nodes of the model which have been captured in at least representative images of the image sequence.
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[0001] This application is a continuation-in-part of Application Ser. No. 10/658,642, filed Sep. 9, 2003, which is currently pending and which is a continuation-in-part of Application Ser. No. 10/459,269, filed Jun. 11, 2003, which is currently pending. The contents of Application Ser. Nos. 10/658,642 and 10/459,269 are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention pertains generally to devices and implements for creating original works of fine art using computerized techniques. More particularly, the present invention pertains to visual works of art having physical enhancements for the presentation of shading depth and definition. The present invention is particularly, but not exclusively useful for creating original works of art using ultraviolet (UV) curable inks and a computerized color printer.
BACKGROUND OF THE INVENTION
[0003] All works of art involve the making or doing of things that display form, beauty, and an unusual or unique perception. In the case of fine art, the characteristics of the work are distinguished by their purely aesthetic value. More particularly, insofar as fine art paintings are concerned, the aesthetic value of a particular work is found not only in its presentation, but also in the contrasts that are introduced into the work by the artist. These contrasts can be either textural or tonal in nature, and will include the shadings, depth and definition that make the artwork extraordinary and unique.
[0004] Reproductions of an original artwork, like the original itself, can also be valuable. The value of a reproduction, however, depends in large part on how faithful the reproduction is in its presentation of the original. For instance, in the reproduction of an oil painting, the ability to accurately incorporate the contrasts that were made by the artist in the original, may greatly enhance the value of the reproduction. Depending on the particular work of art, these contrasts can be many and varied, and will include such nuances as brush strokes and color variations. It is almost needless to say that the contrasts which add so much to a work of fine art are often subtle and, accordingly, quite difficult to reproduce.
[0005] Various devices and techniques have been developed over recent years for the reproduction of visual works. Of particular interest here are the so-called color printers that can accurately reproduce the colors of an original subject. In general, color printing is achieved by any of several printing processes wherein each color is printed separately, in a predetermined order. The superimposed impression, when accurately registered, then builds up an image that corresponds in color to the original subject. Recently, color print processes have been greatly improved by incorporating computer control over the printing process.
[0006] Though very effective, color print processes are somewhat limited by the physical characteristics of the inks that are used in the process. Of particular importance in this regard is the viscosity, or resistance to flow, of the inks that are used. Typically, for operational reasons, the inks that are used in color print processes have rather low viscosities, i.e. they are thin and flow easily. Thus, although the colors in an original work of art may be accurately reproduced using a color print process, the result is an essentially two-dimensional presentation. Consequently, a color print process, alone, will not produce the three-dimensional contrasts that are of crucial importance for the accurate presentation of a work of fine art.
[0007] It is known that inks having viscosities which are much greater than the viscosities required for use in a color print process can be used to provide three-dimensional effects for a reproduced work of art. Specifically, it is known that extremely viscous inks (i.e. so-called “thick” inks) can be effectively incorporated into a reproduced work of art by using screen printing processes. For example, U.S. Pat. No. 4,933,218, which issued to Longobardi for an invention entitled “Sign with Transparent Substrate” discloses the use of screen printing to achieve a three-dimensional effect in an artwork by incorporating an “extremely thick ridge of ink” into the artwork. Ridges alone, however, do not recreate the textural and tonal contrasts found in a work of fine art. Consequently, it may be desirable to conform the viscous ink to a variety of shapes, sizes or configurations. In some instances, however, it may happen that due to an extensive vertical dimension, the variations may deform before the final product can be produced.
[0008] In light of the above, it is an object of the present invention to provide a reproduction of an original work of art, and a method for manufacturing the same, which includes the textural and tonal contrasts that are presented in the original work of art. Another object of the present invention is to provide a reproduction of an original work of art, and a method for manufacturing the same, wherein a screen printing process and a color printing process are used together, in combination, to recreate the contrasts that are found in a work of fine art, and to incorporate these contrasts into a reproduction of the original. Yet another object of the present invention is to provide a reproduction of an original work of art, and a method for manufacturing the same, which includes the use of inks that can be presented in a variety of shapes, sizes or configurations and maintained without premature deformation before the final product has been produced. Still another object of the present invention is to provide a reproduction of an original work of art, and a method for manufacturing the same, which is easy to implement and comparatively cost effective.
SUMMARY OF THE INVENTION
[0009] In accordance with the present invention a method for creating a reproduction of an original work of art is disclosed wherein the textural and tonal contrasts created by the artist in the original artwork are presented in the reproduction. In overview, the methods and products that are disclosed for the present invention involve the creation and combination of various layers of materials. Importantly, the combination of these various layers subsequently serve as the foundation for a color print process.
[0010] For the present invention, a base substrate is provided that has a substantially flat surface. The surface may be either reflective or non-reflective, and it may be of any desired color. Also, the base substrate may be made of paper stock or it may be made of a reflective material, such as aluminum sheeting. Further, if made of paper stock, the base substrate may be coated, or uncoated, or covered with a metallic foil.
[0011] A key aspect of the present invention is that a relief layer is applied to the surface of the substrate. Importantly, this relief layer has ink deposits that are dimensioned and arranged to correspond with the contrasts that were created by the artist in the original work of art. Preferably, the relief layer will include a clear plastic sheet on which the ink deposits have been placed. This clear plastic sheet, along with the ink deposits, can then be bonded directly onto the surface of the base substrate. Alternatively, the clear plastic sheet need not be used and, instead, the ink deposits can be placed directly onto the base substrate. In either case, the ink deposits of the relief layer are created by a screen printing process using a thick, extremely viscous ink. In cases where the art presentation requires significant three dimensional variations in the ink work, it may be desirable to use a viscous, ultraviolet (UV) curable ink. If used, after it has been formed on the relief layer, the UV curable ink may be “set-up” by exposure to ultraviolet radiation before proceeding with subsequent steps in the manufacture of the final product.
[0012] After being screen printed, but before UV curing, the viscous ink deposits of the relief layer can be further refined by manually using other tools, such as a brush or spatula. The purpose in using these various tools is to refine the contrasts that are being incorporated into the reproduction. For example, in the specific case of an oil painting, the contrasts may be refined to give an impression of brush strokes in the reproduction. Further, in order to give the reproduction additional texture, depth and definition, the relief layer can be made by selectively using clear or color tinted inks for the viscous UV curable ink deposits.
[0013] Whenever the surface of the base substrate is reflective in nature, an optional white layer can be used for the present invention. If used, this white layer will be positioned between the reflective surface of the substrate and the relief layer to provide an opacity that will diminish the reflectivity of selected portions of the reflective surface. Like the relief layer, this white layer is preferably created by a screen printing process. Also, like the relief layer, the white layer may include a clear substrate which can then be bonded to the surface of the base substrate. If a white layer is used, the relief layer would be applied onto the white layer.
[0014] Once the various layers have been combined as indicated above, a color print layer is positioned over the relief layer to provide the reproduction with a color replication of the work of art being reproduced. Preferably, for all embodiments of the present invention, the relief layer is located between the surface of the substrate and the color print layer. In this combination, the ink deposits of the relief layer are incorporated into the color replication of the color print layer as contrasts from the original work of art.
[0015] As envisioned for the present invention, the positioning of the color print layer can be computerized. Specifically, the color print layer will include a plurality of variously colored ink dots that are deposited onto the relief layer according to the instructions of a computer program. The computer program is also employed to register the color print layer with the relief layer.
[0016] In addition to making reproductions of other works of art, the methods and processes of the present invention are also applicable for the creation of original works of art. To do this, the artist prepares a computer program for the color print layer according to his/her desires. This computer program is then used to control a color printer for the generation of the color print layer. The relief layer is also prepared by the artist according to his/her desires and, in a first step, is placed or applied to the substrate by a silk screening process. The silk screening can then be enhanced by whatever further refinements may be wanted by the artist. As mentioned above, refinements to the relief layer can be manually introduced by the artist. Specifically is can be done using tools, such as a brush or spatula. If UV curable ink is used, the relief layer can then be set by exposure to ultraviolet radiation. Similarly, an optional white layer can be prepared by the artist and incorporated in the manner discussed above. The substrate with its relief layer and white layer (optional) can then be run through the color printer to create the original work of art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:
[0018] FIG. 1 is an elevational view of a reproduction of a work of fine art in accordance with the present invention;
[0019] FIG. 2 is a cross sectional view of the reproduction as seen along the line 2 - 2 in FIG. 1 ;
[0020] FIG. 3 is an exploded perspective view of the fine art reproduction according to the present invention, showing various layers of the reproduction positioned for combined incorporation; and
[0021] FIG. 4 is a schematic representation of a method for manufacturing a fine art reproduction in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Referring initially to FIG. 1 , a reproduction of fine art that has been manufactured in accordance with the present invention is shown and is generally designated 10 . More particularly, the construction of the reproduction 10 will be best appreciated with reference to FIG. 2 . There it will be seen that the reproduction 10 essentially includes a base substrate 12 on which a white layer 14 has been deposited. Additionally, there is a relief layer 16 and a color print layer 18 which overlies the base substrate 12 to place both the white layer 14 and the relief layer 16 between the base substrate 12 and the color print layer 18 . The actual construction of the reproduction 10 will, perhaps, be best appreciated by cross referencing FIG. 2 with FIG. 3 , and by individually considering each portion of the construction.
[0023] For purposes of the present invention, the base substrate 12 may be made of paper stock, metal sheeting (e.g. aluminum), or any other type of suitable material known in the pertinent art. Regardless of the material used for base substrate 12 , and although the base substrate 12 may be shaped as desired (the rectangular shape shown in FIG. 3 is only exemplary), the base substrate 12 will preferably have a substantially flat surface 20 . As envisioned for the present invention, the surface 20 may be either reflective or non-reflective.
[0024] In the event that the surface 20 of base substrate 12 is reflective in nature, the reproduction 10 may include the white layer 14 . Use of the white layer 14 , however, is optional. If used, the white layer 14 will include a white opaque ink 22 that may be selectively placed on a clear plastic sheet 24 . The white layer 14 is then placed against the surface 20 of base substrate 12 with the white ink 22 covering selected portions of the surface 20 . Alternatively, the white layer 14 need not include the clear sheet 24 and, instead, the white ink 22 may be applied directly to the selected portions of the surface 20 . In either case, the purpose of the white ink 22 of white layer 14 is to provide an opacity that will effectively diminish the reflectivity of the selected portions of the surface 20 . Recall, this white layer 14 is optional. If the surface 20 of base substrate 12 is not reflective, the white layer 14 may not be needed.
[0025] FIG. 3 shows that the relief layer 16 will include deposits of a viscous ink 26 . Preferably, the ink 26 will be clear and will have a relatively high viscosity. The ink 26 may, however, be color tinted. Importantly, and regardless of color, the viscosity of ink 26 must allow the deposits of ink 26 to be configured as needed. Specifically, the deposits of ink 26 in relief layer 16 must be capable of being varied in extent, depth and orientation within the relief layer 16 . The purpose here is to have the deposits of ink 26 replicate, or mimic, the textural and tonal contrasts that are found in the original artwork. Further, it will be appreciated that the deposits of ink 26 in the relief layer 16 may need to be presented in a variety of shapes, sizes or configurations. If so, in order to obviate the possible premature deformation of the deposits of ink 26 , the ink 26 may be a UV curable ink, of a type well known in the pertinent art.
[0026] As also shown in FIG. 3 , the deposits of ink 26 may be placed on a clear plastic sheet 28 . Like the white layer 14 discussed above, however, the relief layer 16 need not include the clear sheet 28 . In any event, with or without the clear sheet 28 , the deposits of ink 26 in relief layer 16 are placed over the white layer 14 . If the white layer 14 is not used, the relief layer 16 may be placed directly against the surface 20 of base substrate 12 .
[0027] Still referring to FIG. 3 , it will be appreciated that the color print layer 18 covers the other layers 14 (if used) and 16 . The sole purpose of the color print layer 18 is to provide a faithful color replication of the artwork being reproduced. Preferably, the color variations of the original artwork are replicated in the color print layer 18 by a computer program that has been prepared and written in accordance with techniques that are well known in the computer art. Thus, as envisioned for the reproduction 10 of the present invention, the color print layer 18 is digitally colorized using known computer techniques.
[0028] Referring now to FIG. 4 , a schematic representation of a process for manufacturing a reproduction 10 in accordance with the present invention is shown. With reference to FIG. 4 it is to be appreciated that, if used, the white layer 14 is placed on the surface 20 to create a base substrate 12 ′. Preferably, this is done by a screen printing process wherein the white ink 22 is passed through a mask (not shown) that has been positioned on a mesh 30 . As is well known in the pertinent art, this process will result in the white ink 22 being applied to only the selected portions of the surface 20 that are not covered by the mask.
[0029] Even though a white layer 14 may not be used, the relief layer 16 is applied to create a base substrate 12 ″. As indicated in FIG. 4 , the relief layer 16 can be applied to the base substrate 12 ″ in a variety of ways using the viscous ink 26 . Specifically, deposits of the viscous ink 26 can be applied to the base substrate 12 using a screen printing process. In FIG. 4 , this screen printing process is represented by the mesh 32 which can be used with a mask (not shown) in a manner similar to that disclosed above with reference to the white layer 14 . Alternatively, or in addition to the screen printing process, deposits of the viscous ink 26 can be manually applied to the base substrate 12 by using a brush 34 or a spatula 36 . Regardless of the particular tool that is used in this task, it is most important that the contrasts found in the original artwork are replicated by the deposits of viscous ink 26 in the relief layer 16 for the reproduction 10 . As mentioned above, these contrasts will be both tonal and textural in nature.
[0030] FIG. 4 also indicates that in the event that the viscous ink 26 is a UV curable ink, a UV source 44 can be used to radiate the base substrate 12 ″ with ultraviolet light. As is well known in the pertinent art, the exposure of UV curable ink to ultraviolet light will cause it to “set up” quickly, and thereby avoid a deformation of the deposit of ink 26 that might otherwise occur.
[0031] Once the relief layer 16 has been applied to the base substrate 12 ″, the color print layer 18 is then incorporated to create the reproduction 10 . Specifically, as indicated in FIG. 4 , the process of incorporating the color print layer 18 into the reproduction 10 is computerized. As with any well known color print process, the present invention envisions the use of a plurality of variously colored inks 38 , of which the colored inks 38 a, 38 b and 38 c shown in FIG. 4 are only exemplary. The individual sources of these colored inks 38 , as well as a computer 40 , are respectively connected to a sprayer 42 . More specifically, the computer 40 is electronically connected to the sprayer 42 and, in accordance with a previously prepared computer program (not shown), the computer 40 controls the flow of the respective colored inks 38 through the sprayer 42 to create the color print layer 18 . Thus, in order from front to rear, a reproduction 10 in accordance with the present invention includes, the color print layer 18 , the relief layer 16 , the white layer 14 (optional), and the substrate 12 .
[0032] When using the techniques and methods of the present invention for the creation of an original work of art, the artist assumes total control over the creation of the various layers 14 , 16 and 18 . In particular, by exploiting the relatively thick viscosity of the ink 26 that is used to create the relief layer 16 , the artist is able to incorporate physical enhancements for the color print layer 18 that would not be possible, otherwise. More specifically, as envisioned by the present invention, for the creation of an original work of art, the artist is free to separately and individually manipulate the white layer 14 , the relief layer 16 , and the color print layer 18 , as desired. Moreover, by introducing variations in at least one of the other layers (e.g. the white layer 14 , or the relief layer 16 ), while using a same color print layer 18 , the artist is able to create different original works which all have a same theme or color scheme, but which all have different contrasts. More specifically, the computerized color print layer 18 can be used to establish a same theme or color scheme for different works. With a common theme or color scheme, reconfigurations of the white layer 14 and/or the relief layer 16 can be made from work to work, to create variations in extent, depth and orientation that will give each work its own original textural and tonal contrasts. As will be appreciated by the skilled artisan, the color scheme of a theme, or the theme itself, can also be changed from work to work, while the relief layer 16 or the white layer 14 (if used) remain the same. In each case, for each new work of art, the color print layer 18 is applied using a computerized color printer (i.e. computer 40 and sprayer 42 ).
[0033] While the particular Method for Manufacturing a Work of Art Using UV Curable Ink as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.
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An original work of art incorporates various layers of different materials in a predetermined order. First, is the base substrate. Next, a relief layer having UV curable ink deposits that present textural and tonal contrasts for the work of art are applied to the substrate. A computerized color print layer is then combined with the relief layer to create the work of art. For substrates having a reflective surface, a white layer can be added between the substrate and the relief layer to selectively reduce reflectivity in the work of art.
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BACKGROUND AND SUMMARY OF THE INVENTION
The present invention is directed to novel watercraft lift assemblies comprising, in certain embodiments, single motor and dual motor/winch assemblies secured to the dock-side portion of the support structure. The present invention does not require the use of top frames for carrying cable shafts necessary to lift the frame supporting the watercraft.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of the present invention.
FIG. 2 is a detailed, partially exploded view of the second pulley assembly connected to one of the transverse beams of the lifting frame.
FIG. 3 is a perspective view of a motor/winch assembly illustrating an exemplary tie off of the first cable.
FIG. 4 is a perspective view of a second embodiment of the present invention.
FIG. 5 is a perspective view of a third embodiment of the present invention.
FIG. 6 is a perspective view of the first pulley in combination with the first cable in the first and third embodiments of the present invention.
FIG. 7 is a perspective view of the cable tie-off in combination with the first cable in the second embodiment of the present invention.
FIGS. 8A and 8B are enlarged views of the preferred cable terminal end tie offs in the present invention.
FIG. 9 is a enlarged view showing a portion of one of the transverse beams with a portion of the support frame secured thereon.
FIG. 10A is a perspective view of the motor/winch assembly of the present invention.
FIG. 10B is a perspective view of the spool bracket portion of the motor/winch assembly used in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the figures, the present invention comprises three different embodiments for the inventive watercraft lift assembly. The term “watercraft,” as used herein, refers to any vehicle designed for operation on any waterway and includes, but is not limited to, outboard motor boats, jet skis, inboard motor boats, pontoon boats, sailboats, jet boats, and the like. In addition, “waterway” includes any lake, river, ocean, gulf, and the like wherein a dock may be typically installed.
FIG. 1 illustrates the first embodiment of the invention which, for ease explanation, is referred herein as the “three-post/dual motor embodiment.” This embodiment comprises a support structure to which the motor/winch assemblies and terminal ends of the lifting cables are mounted or secured, respectively. Specifically, the support structure of the three-post/dual motor design illustrated in FIG. 1 comprises two vertical pilings 11 positioned on the proximal side P (i.e. dock side) of the watercraft (not shown). The vertical pilings are typically spaced about 7 feet to 12 feet from one another. A third vertical piling 12 is positioned on the distal side D of the watercraft (i.e. a distance away from the dock). As shown in FIG. 1, elongated transverse lifting beams 13 are positioned between the pilings by a pair of pulley assemblies and cables.
The embodiment illustrated in FIG. 1 comprises a pair of motor/winch assemblies 14 , each of which is secured separately to one of the proximal pilings 11 . Each winch assembly 14 contains a rotatable spool 15 about which a length of lifting cable 20 is wound. In one embodiment, the spool is secured to a bracket piece 18 which in turn is secured to the motor assembly 17 . One end of the cable is secured to the spool while the other end is tied off near the top end 11 a of the piling (not shown) or to the winch assembly, as shown in FIGS. 1 and 3. The cables may be stainless steel aircraft cable, nylon, or other types of cables or ropes known by those of ordinary skill in the art. The lifting cable 20 is further mounted onto a pulley wheel 30 , as shown in FIGS. 1 and 6. Preferably, about 12 feet to about 24 feet of cable are employed on this portion of the pulley assembly. The first pulley wheel 20 is mounted onto a bolt 21 which, in turn, is used to secure a pair of parallel pulley housing plates 22 to one another. The first pulley wheel 31 is clearly illustrated in FIG. 6, but is hidden from view by one of the parallel plates 22 in the remaining figures. In addition, only a small portion of parallel plates 22 are shown in FIG. 1; however, the plates are more clearly shown in FIGS. 2 and 6. When the motor 14 b is actuated to operate the winch 14 , the spool rotates to release or wind the lifting cable 20 along the pulley wheel 30 . It will be understood by those of ordinary skill in the art that all of the pulley wheels employed in all of the embodiments of the present invention are conventional pulley wheels, each having a sufficiently wide groove 31 for maintaining the lifting cables as they move thereon (see FIG. 6, for example).
Also secured between the parallel plates 22 is a second pulley wheel 32 positioned subjacent to the first pulley wheel 30 . The second pulley wheel 32 is mounted to a second bolt 27 that also serves to secure the parallel plates 22 to one another, as shown in FIGS. 1 and 2. A second cable 33 is employed, wherein one end is secured to one of the vertical pilings 11 below the transverse lifting beams 13 (at 500 , for example) and the other end is secured near the top end 12 a of the third vertical piling (at 500 , for example) as shown in FIG. 1 . The remaining length of cable is aligned, in succession, over the second pulley wheel 32 , beneath a third pulley wheel 34 , along the top surface of the transverse beam, and beneath a fourth pulley wheel 35 mounted to the distal end 13 a of the transverse beam, as shown in FIGS. 1 and 2. A preferred length of this second cable is 26 feet to 36 feet, although the skilled artisan, will recognize that the length may be varied depending upon the size of the watercraft. Moreover, the third and fourth pulley wheels 34 , 35 are preferably mounted onto brackets 40 that are integral with opposing ends of the transverse beams 13 . Preferably, the latter pulley wheels 34 , 35 are mounted within brackets 40 using hollow bolts 50 with zerk fittings.
When the motor/winch assembly in this embodiment is actuated via a single switch (not shown) to lift the transverse lifting beams 13 , the cable 20 pulls the plates 22 upward, thereby synchronistically raising the beams upward. Lowering the transverse beams operates in the same fashion.
FIG. 2 more clearly illustrates the pulley and cable components of the inventive lifting apparatus. Not shown in FIG. 1 but shown in FIG. 2 are a second pair of parallel plates 41 . The lower ends 22 a of the first pair of parallel plates 22 are secured via a bolt 27 , as shown. The second pair of plates 41 provide for more stability during operation of the lift assembly. In addition, the lift assembly preferably includes a cable tunnel 60 configured to protect the second cable 33 from damage. A vertical stabilizing member 63 may also be secured to each of the transverse beams to minimize side-to-side movement of the boat hull. These features of the present invention are preferably present in all of the inventive embodiments illustrated and described herein.
FIG. 4 illustrates a second embodiment of the inventive lifting apparatus which, for ease of explanation, is referred to herein as the “three-post,/single motor design” 300 . In this embodiment, three vertical pilings 301 used for structural support are employed. Specifically, the three-post/single motor embodiment illustrated in FIG. 4 comprises one vertical piling positioned on the dock-side or proximal side P of the water craft (not shown). Two other vertical pilings 302 are positioned a distance away from the dock, for example, and more particularly on the distal side D of the dock. These vertical pilings are typically spaced about 7 feet to 12 feet from one another. In this embodiment, the transverse lifting beams for carrying the watercraft are positioned between the pilings as shown in FIG. 4 .
A winch assembly 14 is mounted near the top end of the first vertical piling 301 . The winch assembly includes a pair of rotatable spools 141 and a motor 14 b for turning the spools. A first cable 200 is wound about each of the spools 141 , with one end of the cable secured to the spool and the other end secured to a bolt 50 connecting the two parallel pulley plates 22 , as shown in FIGS. 4 and 7. Preferably, these cables are from about 12 feet to about 24 feet in length, depending upon the size of the watercraft intended to be lifted.
The three-post/single motor design 100 of the present invention further includes a pair of pulley assemblies, each of the pulley assemblies positioned on one side of the proximal vertical piling 301 as well as one of the transverse lifting beams 13 . More specifically, each of the pulley assemblies includes a pulley wheel 32 secured to the parallel plates by a bolt 50 connecting the two plates, as shown in FIG. 4 . The pulley wheel 32 is positioned subjacent to the upper bolt 50 connecting the parallel plates 22 . Each of the pulley assemblies further includes a second pulley wheel 34 positioned subjacent to the first pulley wheel 32 and mounted onto another bolt 50 . A third pulley wheel 35 is positioned on each of the transverse beams 13 near the distal vertical piling 302 and held therein by a bolt 50 , as shown in FIG. 2 . Preferably, the pulley wheels 34 , 35 positioned on the transverse lifting beams 13 are mounted within brackets 40 using hollow bolts with zerk fittings 52 , as described above for the first embodiment and illustrated in FIG. 2 .
The three post/single motor embodiment 100 of the present invention further includes a set of second cables 33 , with each cable having one end fixedly secured to one side of the proximal vertical piling 301 below the first end 13 b of the transverse beam and the second end fixedly secured to and near the top end 302 a of one of the distal side vertical pilings 302 , as shown in FIG. 4 . The remaining portion of each of the second cables is aligned, in succession, over the first pulley wheel 32 , beneath the second pulley wheel 34 , along the top surface of the transverse beam, and beneath the third pulley wheel 35 on the distal end 13 a of the transverse beam. As shown in FIG. 2, the second and third pulley wheels 35 , 36 are mounted within brackets 40 using hollow bolts with zerk fittings 51 . Preferably, from about 26 feet to about 36 feet of cable 30 are used, depending upon the size of the watercraft intended to be lifted by the inventive lifting assembly.
When the motor/winch assembly in this embodiment is actuated via a single switch (not shown) to lift the transverse lifting beams 13 , the cable 200 pulls the plates upward, thereby synchronistically raising the transverse lifting beams 13 . Lowering the transverse beams operates in the same fashion.
FIG. 5 illustrates a third embodiment of the present invention. In this embodiment, which for ease of explanation is referred to herein as the “four post/dual motor” embodiment 200 , the support structure of the assembly includes a first pair of vertical pilings 211 positioned on the proximal side P (i.e. dock side) of the watercraft W and a second pair of vertical pilings 212 positioned on the distal side D of the watercraft W. This embodiment further includes a pair of transverse lifting beams 13 , which in combination with the other features of the invention, may be lowered or raised to accommodate a watercraft. Each of the two lifting beams 13 is positioned between adjacent distal and proximal pilings 211 , 212 , as shown in FIG. 5 . This embodiment includes a pair of winch/motor assemblies 14 , each of which is secured to one of the proximal pilings 212 near the top end 213 a at 500 , as shown. Each of the winch/motor assemblies 14 includes a spool about which a cable 20 is wound. This first cable 20 is wound about each of the spools 15 (see FIG. 10 A), with the cable having one end fixedly secured to the spool and a second end fixedly secured to either piling of the first pair of vertical pilings 211 or a portion of the winch assembly on each of the first pair of proximal pilings 211 . The first cable 20 is mounted onto the first pulley wheel 34 , as also described above and illustrated for the first embodiment (i.e. see FIGS. 5 - 6 ), and serves to raise or lower the pulley wheel 30 via the motor/winch assembly 14 . The first pulley
A second pulley wheel 34 is housed between a second pair of parallel housing plates 41 and subjacent to the first pulley wheel. Preferably, the second pulley wheel 34 is rotatably mounted on a bolt 50 securing the two parallel plates 41 together. This cable 20 is movably mounted on the first pulley wheel 30 for longitudinal movement upon activation of the motor.
Each of the pulley assemblies further includes a third pulley wheel 34 positioned subjacent to the second pulley wheel 32 on the proximal end 13 a of the lifting beam as well as a fourth pulley wheel 35 positioned on the distal end 13 b of the lifting beam 13 . The third pulley wheel 34 is further rotatably mounted on a bolt 50 secured between the brackets.
The pulley assembly further includes a set of second cables 33 , each having a first end secured to one side of the proximal vertical piling 211 beneath the transverse beam and a second end secured to and near the top of one of the two distal pilings to which it is adjacent. The second cable 33 is further aligned, in succession, over the second pulley wheel 32 , beneath a beneath the third pulley wheel 34 , along the top surface of the beam, and beneath a fourth pulley wheel 35 , wherein the fourth pulley wheel is mounted to the distal end of each of the elongated beams. Preferably, the third and fourth pulley wheels 34 , 35 positioned on the lifting beams are mounted within brackets 41 using hollow bolts with zerk fittings 51 , as described above for the first and second embodiments illustrated herein.
To operate the lifting apparatus, two switches actuated to activate the motor and winches of the motor/winch assembly, thereby causing the first cable 20 to raise or lower the two lifting beams, synchronistically.
FIG. 5 illustrates a boat hull W (in phantom) positioned on the transverse lifting beams 13 . Preferably, the lifting beams are further connected to one another by a pair of cross beams 300 positioned on the top surface of the lifting beams 13 . Preferably, these cross beams 300 are covered with an artificial turf 301 or other suitable material to prevent slippage and scratching of the watercraft hull or bottom. As shown in FIG. 9, the cross beams may be secured to the transverse beams via an L-bracket 302 , for example.
The present invention is also directed to a novel device for safely securing the free end of the lifting cable 33 to the vertical piling. As shown in FIGS. 8A-8B, the cable 33 is aligned within a grooved wedge 400 . The wedge 400 is configured to fit within the slot 508 of a becket which has been bolted onto the vertical piling. FIG. 8B illustrates an L-shaped becket 500 secured to a vertical piling via bolts 502 . The upward force of the cable during operation of the lifting apparatus causes the wedge/cable combination to lock into the slot 50 within the becket, thereby minimizing any slippage of the cable during operation.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention.
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The present invention is directed to novel watercraft lift assemblies comprising, in certain embodiments, single motor and dual motor/winch assemblies secured to the dock-side portion of the support structure. The present invention does not require the use of top frames for carrying cable shafts necessary to lift the frame supporting the watercraft.
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Priority to German Patent Application No. 101 15 875.0, filed Mar. 30, 2001 and hereby incorporated by reference herein, is claimed.
BACKGROUND INFORMATION
The present invention is directed to an image-recording device for a printing form, including an array of light sources and a downstream microoptics which generates a virtual image of the light sources.
The use of light source arrays in rows or in matrix form for recording images on printing forms, whether in a printing-form exposure unit or in a direct-imaging print unit, places high demands on the imaging optics to be used. Typically, the light source arrays are made up of a specific number of diode lasers, preferably of single-mode lasers, which are mounted at a defined distance from one another, usually spaced apart at substantially the same intervals on a semiconductor substrate, and which share a common exit plane that is precisely defined over the crystallographic plane of fracture. The light-emission cones of these light sources or diode lasers open at different widths in the two planes of symmetry which are substantially orthogonal to one another. From this, the necessity arises of an imaging optics which, on the one hand, reduces, preferably minimizes this asymmetry by using a preferably small number of subassemblies, and, on the other hand, renders possible a global imaging of the array of emitters that is as free of aberrations as possible.
From the related art, one knows of a number of optical imaging systems, which are specially implemented for imaging diode laser arrays to form images on a light-sensitive medium. For example, from U.S. Pat. No. 4,428,647, a semiconductor laser array is known, each of whose individual lasers is assigned an adjacent lens between the laser array and the objective lens. The purpose of these lenses is to change the angle of divergence of the light beams emerging from the surface of the laser array, such that the light is collected as efficiently as possible by the objective lenses and is focused at a light sensitive medium. The optical power of these lenses is selected such that, for each laser, a virtual intermediate image is formed behind the emitting surface, whose spacings correspond approximately to the spacings of the emitted light beams, the emitter's intermediate image being magnified.
EP 0 694 408 B 1 describes, for example, how a microoptics is able to reduce the divergence of the emerging light by using axially symmetric optical elements.
The often exceptionally large difference in the lateral field dimensions of a light source array of this kind, for example 10×0.001 mm 2 , therefore requires a specific microscopic and macroscopic image formation. A use of spherical optics for these dimensions can only succeed by employing a relatively large and costly optical design. A disadvantage encountered when using a spherical macrooptics is the variable image quality as a function of the distance to the optical axis. Even the use of cylinder lenses and cylinder lens arrays has, to date, not produced the consistent quality desired for an imaging of a light source array, particularly in the form of a diode laser array.
From U.S. Pat. No. 3,748,015, one knows of an optical system for forming an image of an object with unit magnification and high resolution, which includes an arrangement of a convex and concave spherical mirror, whose centers of curvature coincide at one point. This mirror arrangement produces at least three reflection points within the system and two conjugate regions set apart from the optical axis, at unit magnification in a plane which contains the center of curvature, the optical axis of the system being orthogonal to this plane in the center of curvature. Such a combination of mirrors is free of spherical aberration, coma and distortion, and, when the algebraic sum of the powers or refractive powers of the mirror reflecting surfaces utilized is zero, the image produced is free from third order astigmatism and field curvature. An optical system of this kind is referred to as an optical system of the Offner type.
U.S. Pat. No. 5,592,444, for example, describes a method and a corresponding device for writing and reading data to an optical storage medium, simultaneously in a plurality of tracks. The imaging optics described in this document for a plurality of individually controllable diode lasers includes, in this context, a system of spherical mirrors of the above-described Offner type, thus a combination of spherical concave and convex mirrors having a common center of curvature. However, no virtual, in particular no magnified intermediate image is produced by the divergence-reducing micro optics.
However, the use of an image-recording device for a printing form in a printing-form exposure unit or in a print unit in a printing press requires additional measures. Since, on the one hand, machines of this kind have a very limited assembly space, and, on the other hand, little can be altered on the design or on the configuration of the printing-form exposure unit or on the print unit to implement an image-recording device, it is necessary to reduce the required assembly space. In addition, an imaging optics on a printing press or a printing-form exposure unit is subject to shocks or vibrations, so that it should have as few parts as possible that require relative adjustment. For that reason, known related-art optical systems cannot simply be transferred for use on a printing-form exposure unit or within a print unit of a printing press.
SUMMARY OF THE INVENTION
An object of the present invention is, therefore, to devise an imaging optics for an array of light sources, which will reduce the divergence of the emitted light in simple fashion and render possible an image formation having few aberrations. It is additionally or alternatively intended to realize an imaging optics for an image-recording device for a printing form which will require the least possible amount of overall space and as few as possible parts, and therefore, as few as possible degrees of freedom in the adjustment.
The present invention provides an image-recording device for a printing form ( 29 ), including an array of light sources ( 12 ) and a downstream microoptics ( 14 ) which generates a virtual intermediate image ( 18 ) of the light sources ( 12 ). Arranged downstream from the microoptics is an optical system ( 10 ), which includes at least one sector of a convex mirror ( 26 ) and one sector of a concave mirror ( 24 ) having a common center of curvature, which produces a real image ( 28 ).
The image-recording device according to the present invention for a printing form, having an array of light sources and a downstream microoptics which produces a virtual image of the light sources, is distinguished by the microoptics having the downstream optical system, which includes at least one concave mirror sector and one convex mirror sector having a common center of curvature, the algebraic sum of the powers of the refractive powers preferably being zero, in other words, a macrooptics or combination of the Offner type, which produces a real image of the virtual intermediate image. In the following, a convex and concave mirror arrangement is also discussed in simplified terms, although, here as well, at least one mirror may only have one sector that defines a surface that is simply as well as non-simply cohesive, in a specific subspace angular range of maximally 4π. In this context, one specific embodiment provides, in reality, that the centers of curvature of the concave mirror and of the convex mirror need not coincide with complete precision in order to obtain the desired properties of the Offner-type optical system, exactly enough, for use in an image-recording device according to the present invention.
Using a small number of optically refractive surfaces, in the image-recording device of the present invention, each light source of the array is adapted via a virtual intermediate image to the microscopic requirements, thus, in particular, to the divergence. A downstream macroscopic imaging, utilizing known properties of an Offner-type optical system, thus a combination of at least one convex mirror sector and one concave mirror sector having a common center of curvature, enables points to be advantageously imaged along a line that essentially runs in a circle. The optical system, which, as macrooptics, is positioned downstream from the microoptics, of the image-recording device of the present invention is designed such that the virtual intermediate image points of the light sources, which are essentially arranged in one row, are spaced at a smaller distance to this circular line. In other words: the image-recording device of the present invention makes it possible for the emission from a multiplicity of light sources, in particular from diode lasers, to be constantly corrected using a small number of optical elements. By combining cylindrical lenses, one achieves a micro-optical symmetrization, simultaneously accompanied by magnification, using a virtual intermediate image of each light source and a, to the greatest degree, aberration-free imaging of these virtual intermediate images into a real image, by way of a downstream optical system of a convex mirror and a concave mirror, to create an image-recording device for a printing form having especially beneficial image-forming properties.
To facilitate adaptation of the divergence of the emitted light, the microoptics preferably has an aspherical design. These may be, for example, cylindrical lenses or a combination of anamorphotic prisms. The downstream, macroscopic, optical system of a convex and a concave mirror has at least one circular segment of rotationally symmetric optics, to whose assigned object circle, the essentially straight-line projection of the row of virtual, intermediate image points exhibits a spacing that is kept small, the object circle being situated within one of the two conjugate regions of the optical system of a convex and concave mirror. Thus, using the optical system of the Offner type, the essentially straight-line row of virtual, intermediate image points may be produced as real images, with unit magnification, in the second conjugate region. Especially advantageous in this context is the absence of aberration in the optical system of a convex and a concave mirror.
To reduce the overall space required for the image-recording device of the present invention, the optical path is advantageously folded at least once within the optical system of one convex and one concave mirror. Therefore, at least one path-folding surface is beneficially provided in the optical system situated downstream from the microoptics, whether it be upstream and/or downstream from the reflective surfaces of the optical system of a convex and a concave mirror. This yields a compact optical path through the imaging optics of the image-recording device of the present invention, so that it is possible to reduce the overall required space for an implementation within a printing-form exposure unit or a print unit. Moreover, at least one part of the optical system of a convex mirror and of a concave mirror may be fashioned quite advantageously as a single component, thus monolithically from a suitable material having a refractive index that differs from the ambient environment, for example from a glass or a another transparent material. The individual component, i.e., the monolith may then have partially internally reflecting surfaces, which, for example, form the concave and convex reflective surfaces, respectively, of the optical system of a convex and a concave mirror. These internal surfaces are also described as the active internal surfaces of the monolith. Provided at the monolith are at least one entrance window and one exit window for the light emitted by at least one light source, the windows preferably having an antireflection coating in the form of an interference filter. In one advantageous further embodiment, other optical elements, such as prisms or path-folding surfaces may be assigned to the monolithic structure for purposes of beam deflection.
An image-recording device according to the present invention may be utilized to special advantage in a printing-form exposure unit or in a print unit. A printing press in accordance with the present invention, which includes one feeder, at least one print unit, and a delivery unit, has the distinguishing feature of having at least one print unit equipped with an image-recording device according to the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages, beneficial specific embodiments, and further refinements of the present invention are presented on the basis of the subsequent figures and descriptions thereof. In detail, the figures show:
FIG. 1 a schematic representation of a configuration of optical elements in one specific embodiment of the image-recording device according to the present invention for a printing form;
FIG. 2 a schematic representation of a configuration of optical elements in an alternative specific embodiment of the image-recording device according to the present invention, including additional beam-profile filters;
FIG. 3 a schematic representation illustrating the position of the focal line of the optical system of the convex mirror and concave mirror with respect to the row of virtual image points of the array of light sources;
FIG. 4 a schematic representation of a monolithically constructed optical system of a convex mirror and a concave mirror;
FIG. 5 a schematic representation of a monolithically designed, alternative optical system of a convex mirror and a concave mirror, utilizing two path folds;
FIG. 6 a schematic representation of a symmetric, monolithically designed, alternative optical system of a convex mirror and a concave mirror, including additional path-folding elements in the form of prisms; and
FIG. 7 a schematic representation of a monolithically designed, alternative optical system of a convex mirror and a concave mirror, including a convex sphere and a prism for coupling in the light to be imaged.
DETAILED DESCRIPTION
FIG. 1 shows a schematic representation of a configuration of optical elements in one specific embodiment of the image-recording device according to the present invention for a printing form. The image-recording device of the present invention has a light source 12 , including an assigned microoptics 14 , and a downstream optical system 10 . Divergent light 16 emitted by light source 12 is imaged by microoptics 14 onto a virtual image 18 . Through downstream optical system 10 , light beams 20 , emanating from virtual intermediate image 18 via various optical elements, are transformed into a real image point 28 . In this specific embodiment, optical system 10 has, first of all, a deflecting element 22 and, configured along optical axis 23 and rotationally symmetric thereto, a pair of mirrors, concave mirror 24 and convex mirror 26 , having a common center of curvature 25 along optical axis 23 . This pair, made up of concave mirror 24 and convex mirror 26 , images points in one object region onto points in an image region. These regions are conjugate to one another. The symmetry of the optical path through optical system 10 is broken by additional deflecting element 22 , so that, as a conjugate point, virtual intermediate image 18 is assigned to image point 28 , and not conjugate point 27 without a deflecting element in printing form plane 29 . The optical path length between virtual intermediate image 18 and concave mirror 24 is, however, equal to the optical length between concave mirror 24 and image point 28 in printing form plane 29 .
While in FIG. 1, the imaging of a light source 12 using microoptics 14 and a downstream optical system 10 , thus a macrooptics, is graphically shown to facilitate a better understanding of the image-recording device of the present invention, in a corresponding, preferred specific embodiment of the present invention, a plurality of light sources 12 , typically arranged in a row, is imaged by a microoptics 14 , preferably individually formed for each light source 12 , and by a macrooptics acting on the plurality of intermediate images 18 , in accordance with optical system 10 of a convex and a concave mirror.
FIG. 2 shows a schematic representation of a configuration of optical elements in an alternative specific embodiment of the image-recording device according to the present invention for a printing form, including an additional beam-profile filter. In this context, the image-recording device of the present invention includes a light source 12 , microoptics 14 , an entrance window 32 into an encapsulation 33 , in which optical system 10 is situated, and an exit window 34 , printing form 29 being configured subsequently thereto. Here, optical system 10 includes a deflecting element 22 , a concave mirror 24 , a wavefront-correction element or beam-forming element 30 , a so-called beam-profile filter, preferably for transmitting the fundamental mode of light source 12 , for example having a Gaussian beam profile, and a concave mirror 26 . Optical system 10 is, thus, likewise that of a convex mirror and a concave mirror having conjugate regions, virtual intermediate image 18 being generated from divergent light 16 from light source 12 using microoptics 14 in the first conjugate region, and image point 28 in printing form plane 29 in the second conjugate region. By folding the optical path, as shown, using deflecting element 22 , whether it be, as shown here in FIG. 2, passing in front of convex mirror 26 , crossing optical path between convex mirror 26 and concave mirror 24 , or alternatively thereto, passing behind the convex mirror, it is possible to achieve an even more compact design.
In a schematic representation, FIG. 3 elucidates the position of a focal line, i.e., selected points in a first conjugate region of the optical system of a convex and concave mirror with respect to the row of the virtual image points of the array of light sources. FIG. 3 shows a projection along optical axis 23 of concave mirror 24 and of convex mirror 26 of optical system 10 . The essentially circular focal line 36 represents the projection of the conjugate regions on concave mirror 24 for the case of a symmetrical path of rays selected here exemplarily. In other words: the object point and the image point of the optical system of a convex mirror and of a concave mirror lie essentially in phase opposition on a circular focal line 36 , thus 180 degrees out of phase about optical axis 23 . Focal line 36 essentially describes those points having an optimal advantageous transformation property, thus having minimal aberrations. The aim, at this point, is to approximate the row of virtual image points 38 of this focal line 36 . In so doing, it is unimportant in the context of the present invention which precise metrics or measure is selected to measure the distance of line 38 to circular segment 36 . As a measure, one may utilize, for example, the average distance of the light sources in projection 38 to optical axis 23 , thus the sum of the distances divided by the number of light sources. To achieve an advantageously aberration-minimized imaging through optical system 10 , the distance of the projection of the row of virtual image points 38 to the radius of focal line 36 is kept small or is adapted.
In addition, it is clear that optical system 10 of a convex and a concave mirror should be designed such that the projection of focal line 36 exhibits a largest possible radius of curvature. In other words: considered locally, thus considered in the projection of light sources 38 , on the scale of the light sources' image point distances which are maximally distant from one another, focal line 36 should have a flattest possible curve shape in comparison to the projection of the row of light sources 38 . Thus, the employed optical system 10 only needs to have at least one circular segment of a rotationally symmetric optics of a convex mirror and of a concave mirror.
FIG. 4 is a schematic representation of a monolithically designed specific embodiment of the optical system in the image-recording device according to the present invention. A monolithic design is employed to further reduce the size of the optical system of a convex and a concave mirror. Such a monolithic design is exemplified in FIG. 4 by a symmetric path of rays. Optical system 10 is symmetrical to axis 41 . Emanating from virtual intermediate image 18 of the light source (not shown here), together with microoptics, light beams 20 pass through an entrance window 32 into a monolith 40 , which is made exemplarily of a highly refractive glass or of a polymer that is transparent to the employed wavelength. The monolith has a concave surface 42 , which reflects light beams 20 , so that they impinge on an essentially plane reflecting surface 46 facing opposite concave surface 42 . From reflecting surface 46 , the beams are thrown at a convex surface 44 , emanating from there, symmetrically on the other side of axis of symmetry 41 , in turn, reflecting surface 46 and, subsequently, concave surface 42 , are hit by the light beams, until they exit the monolith through an exit window 34 and converge in an image point 28 , appropriately in the printing-form plane (not shown here). The monolithic design, as shown in this FIG. 4, utilizes the fact that, in an optical system of a convex and a concave mirror, it is above all those regions of the concave mirror, which are distant from the optical axis or axis of symmetry 41 , that are used for reflecting light beams from the first conjugate region to the convex mirror, and from the convex mirror into the second conjugate region. This makes it possible to introduce a reflecting surface 46 , so that concave surface 42 in the vicinity of the optical axis or axis of symmetry 41 , may be replaced by a convex surface 44 . The position and the curvature are, of course, determined by the conditions of an optical system of a convex mirror and a concave mirror. Convex surface 44 corresponds to a convex mirror at position 48 , upon which light beams 20 would impinge along optical paths 50 , if there were no reflecting surface 46 . While the sides of monolith 40 , off of which light beams 20 are to be reflected, are made as reflective as possible by suitable coatings, whether by a metal coating or interference filters, an antireflection coating, for example an interference filter, is provided for entrance window 32 and/or for exit window 34 , to achieve a strongest possible coupling of the light into and out of the monolith.
FIG. 5 schematically depicts a monolithically designed, alternative optical system of a convex mirror and a concave mirror, utilizing two path folds. A light source 12 is transformed by microoptics 14 into a virtual intermediate image 18 . Light beams 20 emanating from this virtual intermediate image 18 enter into monolith 40 and are projected at a first deflecting surface 51 onto a concave surface 42 . Light beams 20 then impinge on a reflecting surface 46 , on a convex surface 44 , once more on reflecting surface 46 and on concave surface 42 , to then leave monolith 40 through an exit window 34 and converge in an image point 28 .
A symmetrically designed alternative optical imaging of a convex mirror and of a concave mirror is schematically shown in FIG. 6, deflecting elements being additionally used in prismatic form. Light beams 20 , emanating from virtual intermediate image 18 from light source 12 (not shown here), enter into a prismatic deflecting element 54 , off of whose base they are reflected, to then attain monolith 40 . A symmetrical optical path is provided. Light beams 20 first impinge upon a concave surface 42 , a reflecting surface 46 , a convex surface, and once again on reflecting surface 46 and on concave surface 42 . Likewise provided subsequently thereto is a prismatic deflecting element 54 , off of whose base, light beams 20 are totally internally reflected. The light converges in an image point 28 .
FIG. 7 is a schematic representation of another monolithically designed, alternative optical system of a convex mirror and a concave mirror, including an additional convex sphere and a prism for coupling in the light to be imaged. Light 20 from a virtual intermediate image 18 of a light source (not shown here), together with microoptics, enters into a prism 58 and, from there, into a convex sphere 56 . In its surface, a region is provided, through which light beams 20 are able to enter, in the most reflection-free possible manner, into monolith 40 . Light beams 20 are reflected off of the numerous internal surfaces of the monolith. These internal surfaces include facet 60 , a concave surface 42 , a reflecting surface 46 , and a convex surface 44 . The optical path of light 20 is indicated up to image point 28 . The light is able to leave monolith 40 through an exit window 34 . Typically, convex surface 44 is reflecting, so that light is reflected inside monolith 40 .
The device for recording images in accordance with the present invention may provide images at a form cylinder in a print unit. A cylinder of this kind may constitute part of a printing press, for example as a substitute for the form cylinder in a print unit of the printing press in U.S. Pat. No. 6,318,264, which is hereby incorporated by reference herein.
Reference Numeral List
10
optical system
12
light source
14
micro-optics
16
divergent light
18
virtual intermediate image
20
light beam
22
deflecting element
23
optical axis
24
concave mirror
25
center of curvature
26
convex mirror
27
conjugate point without deflecting element
28
image point
29
printing-form plane
30
beam-forming element
32
entrance window
33
encapsulation
34
exit window
36
projection of the focal line
38
projection of the light sources
40
monolith
41
axis of symmetry
42
concave surface
44
convex surface
46
reflecting surface
48
position of the convex mirror
50
light beams without reflecting surface
51
first deflecting surface
54
prismatic deflecting element
56
convex sphere
58
prism
60
facet
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An image-recording device for a printing form ( 29 ), including an array of light sources ( 12 ) and a downstream microoptics ( 14 ), which generates a virtual intermediate image ( 18 ) of the light sources ( 12 ), which is distinguished by the microoptics ( 14 ) having a downstream optical system ( 10 ) of a convex mirror ( 26 ) and of a concave mirror ( 24 ) having a common center of curvature, a combination of the Offner type, which produces a real image ( 28 ) of the virtual intermediate images ( 18 ). By employing a monolithic structure ( 40 ) of the optical system ( 10 ) of a convex mirror ( 26 ) and of a concave mirror ( 24 ), a more compact, space-saving design is able to achieved. The image-recording device according to the present invention may be utilized to special advantage for a printing form ( 29 ) in a plate-exposure unit or in a print unit of a printing press.
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This is a division of application Ser. No. 07/613,344 filed Nov. 14, 1990, pending.
FIELD OF THE INVENTION
This invention relates to a carton formed from a folded blank. More particularly, it relates to a carton blank and related method for preventing excess glue from being applied to the blank.
BACKGROUND OF THE INVENTION
Folding cartons used to package a variety of different products are formed in packaging machines from folded carton blanks. The folded blanks are basically in the form of collapsed sleeves formed by the carton blank manufacturer from a flat blank comprised of foldably connected panels. To form a collapsed sleeve, a glue flap connected to one of the end panels is adhered to the edge portion of the opposite end panel after the blank has been folded into proper position. In such a blank the tabs or flaps which eventually form the ends of the package are in unfolded condition extending from the leading and trailing ends of the blank as it moves through the blank forming machine.
While it is of course essential to apply a sufficient amount of glue to the glue flap to hold the carton together, it is also important not to apply so much that it squeezes out from between the glue flap and the opposite end panel during formation of the collapsed folded carton blank. When this occurs, the collapsed carton blanks may adhere to each other in the stacks in which they are shipped, and the excess glue may prevent the collapsed blanks from being opened in the final packaging operation. If collapsed blanks cannot be readily opened in the packaging machine, the blanks jam up, requiring the machine to be shut down to remove the jam. This slows the overall packaging process considerably and is to be avoided if at all possible.
Glue is conventionally applied by a glue wheel to carton blanks having only one glue line Although glue wheel application is desirable from the standpoint of assuring that sufficient amounts of glue are applied during a high speed collapsed carton blank forming operation, the difficulty in controlling the quantity applied gives rise to the problem of excessive glue application. In addition, variations in operating conditions, such as in the paperboard thickness and in the pressure applied by the press rolls used to press the glue flap and opposite end panel together, can also cause glue to be squeezed out from between the glued segments.
It would be highly advantageous to be able to better control the gluing operation to prevent the application of excessive amounts of glue. It would also be desirable to control the gluing operation in a manner which does not require extensive changes to the blank forming machine and does not require it to run slower.
SUMMARY OF THE INVENTION
A folding carton blank of the usual type is provided, wherein the blank comprises at least one interior panel section and opposite end panel sections, each panel section being connected to an adjacent panel section by a fold line. A glue flap is connected to one of the end panel sections by a fold line and is adapted to be glued to the other end panel section. In accordance with the invention, the glue flap, which is adapted to receive glue on one face from a glue wheel, is provided with a protrusion on the opposite face, along with a corresponding recess on the glue face. The protrusion and recess are located near the trailing edge of the glue flap and may take various forms, such as a protrusion which is continuous from its point of inception to the trailing edge of the glue flap, resulting in a continuous recess in the opposite glue face, or a ridge spaced from the trailing edge, resulting in a corresponding channel in the glue face.
The protrusion in this arrangement acts to push the glue wheel back-up support means away from the glue wheel to prevent the application of glue to the trailing portion of the glue flap and also to accommodate any excess glue which may have been present.
These and further details and aspects of the invention, as well as their benefits, will readily be ascertained from the more detailed description of the preferred embodiments which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of a carton formed in accordance with the invention;
FIG. 2 is a schematic pictorial view of a portion of a carton blank forming line which may be utilized in carrying out the invention;
FIG. 3 is an enlarged partial pictorial view of one embodiment of the glue flap design of the present invention;
FIG. 4A is an enlarged partial sectional view of the glue station, taken along line 4--4 of FIG. 2, showing the glue wheel contacting an intermediate portion of a glue flap;
FIG. 4B is an enlarged partial sectional view similar to that of FIG. 4A, but showing the glue wheel contacting the trailing edge portion of the glue flap;
FIG. 5 is an enlarged partial sectional view of the glue flap and adhered panel in the press roll station, taken along line 5--5 of FIG. 2, illustrating the effect of the glue flap design of the embodiment of FIG. 3;
FIG. 6 is a partial pictorial view similar to that of FIG. 3, but showing another form of the invention;
FIG. 7A is an enlarged side elevation similar to that of FIG. 4A, but shown in connection with the embodiment of FIG. 6;
FIG. 7B is an enlarged side elevation similar to that of FIG. 4B, but shown in connection with the embodiment of FIG. 6; and
FIG. 8 is an enlarged partial sectional view of the press roll section similar to that of FIG. 5, but illustrating the effect of the glue flap design of the embodiment of FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a typical folding carton 10 comprises side panels 12, connected to end panels 14 along fold lines 16 and 18. The fold line 18 does not directly connect the panels 12 and 14, but connects panel 14 to glue flap 20, shown in dotted lines, which has been adhered to the inner surface of the panel 12. The top of the carton is shown in open condition, with closure flaps 22 and 24 foldably connected to the side and end panels. Similar flaps, not shown, are connected to the side and end panels at the other end to form the bottom panel.
As shown in FIG. 2, the carton of FIG. 1 is formed from a flat blank 26 which is moved by suitable means, such as belts 28 and cooperating pressure rolls 30 through a series of stations of a collapsed carton blank forming machine. As illustrated, the glue flap 20 of the blank passes between a glue wheel 32 and back-up wheel 34 comprising a glue station 35. The lower portion of the glue wheel rotates through a glue reservoir 36, picking up glue G on the periphery of the wheel and transferring it to the underside of the glue flap.
After passing through the glue station, the end panel 14 of the moving blank is folded up by stationary plows or arms 38 and down over folding bar 39 by rotating plow 40. As a result of this folding operation, the panel section 14 now overlies the adjacent panel 12, and the attached glue flap 20 is located intermediate the edges of the panel blank, with the glue side facing up. Similarly, downstream stationary and rotating plows 42 and 44, respectively, fold the opposite side panel 12 over a folding bar 45 so that its edge portion overlies the glue flap 20. Pressure rollers 46 and 48, comprising a bonding station 49, then apply sufficient pressure to bond the glue flap to the side panel 12. It will be understood that the steps described in connection with FIG. 2 are intended to represent any suitable method for folding a blank into collapsed or sleeve form, as long as the method includes the application of glue by means of a wheel and the subsequent application of pressure to bond the glue flap to an adjacent panel. It will be appreciated that not all of the structure normally utilized in a carton blank forming machine has been shown since it was not necessary to an understanding of the invention and would tend to obscure the schematic representation of FIG. 2.
Referring now to FIG. 3, which shows the glue flap of the blank 26 in greater detail, it can be seen that the trailing edge of the glue flap 20 has been embossed out of the plane of the rest of the flap as indicated at 50. Thus the upper surface 52 of the embossed section 50 extends upwardly a greater distance than the upper surface 54 of the remainder of the flap 20, and the lower surface 56 of the embossed section extends a similar distance above the lower surface 58 of the remainder of the flap 20. It will be understood that the lower surfaces 56 and 58 of the flap form the face of the glue flap that receives glue at the glue station 35.
The passage of the glue flap of the blank through the glue station is illustrated in FIGS. 4A and 4B. As shown in FIG. 4A, the spring 59 biases the back-up wheel 34 against the flap 20, forcing the underside of the flap into contact with the glue wheel 32. As a result, glue G picked up by the glue wheel from the reservoir 36 is transferred to the underside 58 of the flap 20 in the form of a layer. When the embossed portion 50 reaches the back-up wheel 34, however, the leading portion of the embossment pushes the back-up wheel upwardly against the force of the spring 58. When this occurs the back-up wheel no longer presses the glue flap against the glue wheel, with the result that the glue wheel no longer contacts the lower surface of the flap and does not transfer glue to it. Because the speed of the moving carton blank is so fast, by the time the spring 58 pushes the back-up wheel down to its normal operating position the trailing edge of the glue flap will have moved past the glue wheel, and the portion of the glue flap between the leading boundary of the recess and the trailing edge of the flap and will not have received any glue. It can be seen that the protrusion has to be near the trailing edge of the glue flap in order for the trailing edge to have time to move past the glue wheel before the back-up wheel returns to its operative position. This arrangement also assures that a sufficient portion of the length of the glue flap receives glue so as to adequately secure the glue flap to the opposite end panel of the blank.
As shown in FIG. 2, after the glue flap and attached panel 14 have been folded over and the end portion of the end panel 12 has been folded over into overlying relationship, the blank passes through the bonding station 49. As further illustrated in FIG. 5, the combined glue flap 20 and panel 12 thus pass between the pressure rolls 46 and 48 which apply sufficient pressure to cause the glue G to bond to the surfaces of the glue flap 20 and panel 12. As the blank continues to move through the bonding station, the pressure rolls tend to squeeze any excess glue which may have been applied toward the trailing edges of the glue flap and panel. In conventional processes, such glue can be present in enough quantity to be forced from between the glue flap and panel, spilling over onto other adjacent portions of the blank. As can be seen in FIG. 5, however, due to the gluing operation described above the trailing edge portion of the glue flap does not receive glue from the glue wheel 32, thus providing no glue to be squeezed out of this area at the bonding station. Further, the larger gap between the glue flap and the panel 12 in the trailing edge portion resulting from the embossed portion of the glue flap provides additional space for receiving glue squeezed from the downstream portion of the assembly. Thus the simple expedient of embossing the trailing portion of the glue flap prevents glue from being applied to the troublesome trailing area of the glue flap, and also accommodates glue which may otherwise have been squeezed into that area.
Referring now to FIG. 6, which shows another embodiment of the invention, the glue flap 20' is embossed in the form of a ridge 60 in the upper face of the flap, which forms a corresponding channel 62 in the lower face of the flap. The flap downstream from the embossment is similar to the flap upstream from the embossment, in that the upper face 64 is at the same level as the upper face 54' and the lower surface 66 is at the same level as the lower face 58'.
Referring to FIGS. 7A and 7B, when the glue flap 20' passes through the glue station, glue G is applied by the glue wheel 32 to the underside 58' of the flap until the ridge contacts the back-up wheel 34 and pushes it upwardly against the force of the spring 58. As in the case of the first embodiment, when this occurs the back-up wheel no longer presses the glue flap against the glue wheel, with the result that the glue wheel no longer contacts the lower surface of the flap and does not transfer glue to it. By the time the spring 58 pushes the back-up wheel down to its normal operating position the trailing edge of the glue flap will have moved past the glue wheel, and the portion of the glue flap between the channel 62 and the trailing edge of the flap will not have received any glue. As in the first embodiment, the protrusion is near the trailing edge of the glue flap, enabling the trailing edge to move past the glue wheel before the back-up wheel returns to its operative position.
FIG. 8 shows the glue flap 20 and overlying panel 12 as they are passing through the pressure rolls 46 and 48 in the same manner as shown in FIG. 5. Because there is no glue in the area from the cavity 62 to the trailing edge of the glue flap, the glue flap 20' and the overlying panel 12 would not normally be adhered in this area. If too much adhesive has been applied to the leading portion of the glue flap, however, the excess glue would normally be squeezed into the trailing portion and possibly out onto adjoining surfaces of the carton blank. In this case, the likelihood of excess glue having been applied is small due to the automatic discontinuance of glue application in the trailing portion of the glue flap as a result of the function of the ridge 60. Moreover, the channel 62 would receive any excess glue which may have been applied and squeezed out in the bonding station.
It should now be apparent that the invention provides a simple yet highly effective method for preventing excess glue from being squeezed from between the glue flap and the panel edge to which it has been adhered, thereby preventing subsequent problems of opening the collapsed carton blanks so produced.
It will be understood that the thickness of the glue flap and panels has been made greater than actual size in the drawings in order to better illustrate the invention, and that the actual height of the protrusions and the depth of the associated recesses would be quite small The principles illustrated and described, however, are accurate regardless of the thickness of the material of the blank.
It should also be apparent that the invention is not limited to all the specific features described in connection with the preferred embodiments, but that changes which do not alter the overall function and concept of the invention may be made without departing from the spirit and scope of the invention, as defined in the claims.
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A modified glue flap of a folding carton blank for preventing glue from being squeezed out during the step of adhering the glue flap to the opposite end panel. The face of the glue flap engaged by the glue back-up wheel includes a protrusion near the trailing edge of the flap. Engagement of the protrusion by the back-up wheel causes the glue wheel to skip the trailing area of the flap. The absence of glue in this area prevents glue from being squeezed out when sealing pressure is subsequently applied to the glue flap and the opposite end panel. The protrusion may take the form of an embossed ridge, forming a channel on the opposite side of the protrusion for receiving any excess glue which would have been squeezed out.
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RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 09/728,946 entitled “Motorhome With Increased Interior Height” filed Dec. 1, 2000 and claims the benefit of U.S. Provisional Application No. 60/318,136 filed Sep. 7, 2001 entitled “Motorhome HVAC System”.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the field of vehicle heating, venting, and air conditioning (HVAC) systems and, in particular, to an HVAC system adapted for motorhomes in which the HVAC system is substantially positioned outside the living portion of the motorhome and employs a common air return system.
2. Description of the Related Art
Motorhomes have become an increasingly popular and common means of recreation. Motorhomes are self-propelled vehicles that include a living space inside. Motorhomes typically provide sleeping areas, cooking facilities, and self-contained water supplies and toilet facilities. More elaborate motorhomes can include refrigerator/freezer units, showers and/or bathtubs, air conditioning, heaters, built in generators and/or power inverters, televisions, VCRs, and clothes washers and dryers. Motorhomes provide many of the amenities of a residential home while on the road away from home and are popular for this reason. Motorhome users will typically use the motorhome to travel to a recreational area and live in the motorhome for some period of time. It is not unusual for people, particularly retired persons, to use a motorhome as their primary residence. Motorhome users often have families with children and, as their trips are often of a recreational nature, will often invite friends or family along on the trip.
It can be understood that since a motorhome will often be used by a large number of people and often for an extended period of time, the motorhome manufacturers and customers will seek as many amenities and as much interior living space as possible. A major goal of motorhome manufacturers and their customers is to maximize the amount of usable living space inside their motorhomes. However, the overall size of an motorhome is limited both by vehicle code regulations and by practical limitations on what is reasonable to drive and maneuver. Vehicle codes restrict the maximum height, width, and length of vehicles that may be driven on public roads. Also, as a vehicle increases in size, it becomes increasingly difficult to drive and can become physically too large to pass through locations that the driver may wish to go. In addition, as the motorhome gets physically larger, more fuel is required to move it, which increases the cost of operation.
An additional design constraint on the construction and design of motorhomes is their overall weight. Since an motorhome is intended to be mobile, an integral power plant is provided and the engine and drive-train have an upper design limit on the weight each is capable of moving. In addition, the chassis, suspension, wheels, and brakes of a motorhome also have upper design limits as to how much weight they can safely accommodate. These weight limits are established after careful engineering analysis and the weight ratings are endorsed and enforced by responsible governmental agencies. Exceeding the established weight limits of a power-train or chassis component can lead to excessive wear and failure, unacceptable performance, and exposure to liability in case of an accident. It is also highly desirable that as much payload as possible is available to accommodate passengers and cargo, i.e. available weight load between the wet weight of the motorhome and the total maximum gross weight of the motorhome.
A particular issue with the weight of a motorhome is its distribution along a vertical axis. The distance of a vehicle's center of mass from the road surface has a dramatic effect on the handling characteristics of the vehicle. The closer the center of mass is to the road surface, the shorter the moment arm between the center of mass and the roll axis of the vehicle. The shorter the moment arm between the center of mass and the roll axis of the vehicle, the less tendency the vehicle will have to lean in turns. Leaning in turns is uncomfortable for the occupants and typically places uneven loads on the tires and suspensions, compromising turning ability. Motorhomes, typically being quite tall, often exhibit significant leaning in turns. To minimize this leaning, within the height available in a motorhome, the weight should be concentrated as low as possible. For this reason, heavy items, such as generators, storage and holding tanks for water and fuel, and the engine are optimally placed low in the chassis.
Since motorhomes are mobile structures, they are typically exposed to the stresses of driving over roads that are in places quite rough. In addition, an motorhome will often have to travel over some distance of dirt surface to reach a camping space. Since an motorhome is typically used outdoors, it is exposed to the stresses of inclement weather and high winds. It can be appreciated that structural integrity is highly desired in an motorhome. However, the weight and size limitations previously mentioned place a limit on the strength of an motorhome. Accordingly, motorhomes are constructed to be as strong, but as light as possible.
The chassis of a motorhome is typically constructed on a steel ladder frame chassis. The chassis is a partially complete vehicle and is generally procured from a manufacturer such as or FORD MOTOR COMPANY. The chassis typically consists of two parallel frame rails extending the length of the chassis and interconnected with several perpendicular cross-braces to form a ladder frame. An engine, transmission, and fuel tank(s) are generally placed between the frame rails near one end. Suspension, steering, brake, and road wheel assemblies are attached outboard of the frame rails.
The coach bodywork, which provides and encloses the living space of the motorhome, is typically made from a laminate that can include light gauge sheet metal, plywood, vinyl, and insulation. The laminate is built to be strong, lightweight, weather resistant, and durable. The coach bodywork may also include a supporting framework. The floor of the coach typically rests indirectly on the chassis frame and the vertical walls extend upwards from the floor. The roof of the coach rests on and depends on the vertical walls of the body for structural support.
A completed motorhome may be up to 45′ long and 13′6″ high in most states. The chassis is generally on the order of 1′ high and is elevated some distance above the ground by the suspension and wheels to provide ground clearance for suspension movement and clearing obstacles in the road. The interior flooring in current art motorhomes is typically elevated a significant amount above the upper face of the chassis in order to facilitate installing ancillary equipment. In addition, many prior art motorhomes route cooling or heating air ducts adjacent the roof structure or mount air-conditioning units on the roof. Under the overall height limit previously mentioned, these structures in or on the roof intrude into the available interior height envelope and limit the usable interior vertical space.
It is sometimes the practice in the art to place major components of an HVAC system, particularly air-conditioning (A/C) condensers and compressors, on the roof of the motorhome. Placement of these A/C components on the roof does not take up limited and valuable interior space inside the coach. Placement of these A/C components on the roof also exposes the condenser to fresh air which increases the efficiency of the heat transfer performed by the A/C system.
Placement of A/C systems and/or associated ducting in the roof does however create a difficulty with water condensation. As air conditioning units cool air to a temperature below the ambient temperature, it is understood that in many conditions the temperature of the air conditioning unit and ducting carrying the cooled air will be below the ambient dew point and thus liquid water will condense on the cool surfaces. If these cool surfaces are located above living areas of the motorhome, as is the case with many current designs, the liquid water can be readily drawn by gravity into the interior of the motorhome. It will be appreciated that liquid water intruding into the interior of the motorhome is an annoyance at best and can damage the structural integrity of interior structures as well as staining or warping interior finishings. Liquid water can also irreparably damage electronic equipment, such as laptop computers, televisions, and VCRs, such as would often be located in the interior of a motorhome. Therefore the condensed water is typically routed to run off the exterior surface of the RV. However this external draining tends to leave unsightly stains and can drip on persons underneath.
In an A/C system the evaporator is that portion of the system that absorbs heat from the ambient air thereby cooling the air and providing the air-conditioning effect. The evaporator portion of A/C system is thus preferably placed in proximity to the space to be air conditioned and the condenser and compressor portions can be readily placed elsewhere and joined to the evaporator by fluid lines. A heater or furnace in contrast does not typically comprise separate components that can be readily separated. Thus, the heater or furnace portion of a typical HVAC system is a unitized assembly, separate from the A/C system that is preferably also placed in the space to be heated, i.e. the interior of the motorhome coach. Disadvantageously, the combustion of fuels such as propane to heat air and the operation of fans to drive heated air into the interior of the coach tends to be noisy. Thus, placement of the furnace inside the coach, while better for heating efficiency, creates an annoyance for the occupants due to the noise of operation.
A further drawback to conventional HVAC systems known for motorhomes is that they have separate A/C and heating units with separate air ducting and filtering systems. Air is routed through the air conditioning unit through ducting and filtering members that are completely separate from the heating unit's ducting and filtering members. This ducting duplication results in additional separate heating and air-conditioning air filters that require periodic changing as well as additional interior space consumed by the ducting. As previously mentioned, interior space within the coach is highly valuable and preferably maximized for the occupants comfort and utility.
From the foregoing, it can be appreciated that there is a continuing need for a stronger motorhome coach construction that also provides increased interior living space. The structure should minimize weight to the motorhome and should also maintain as low a center of gravity as possible to benefit vehicle handling characteristics. There is also a need for a HVAC system that positions noisy components outside the interior of the coach and minimizes redundancies in ducting and filters to reduce costs and increase interior space and serviceability. The HVAC system preferably position the A/C condenser and ducting in such a way that water that condenses out during use does not intrude into the interior of the motorhome.
SUMMARY OF THE INVENTION
The aforementioned needs are satisfied by the present invention, which in one aspect is
as stated, the heating component is positioned outside of the interior of the motorhome. It is understood that the heating component will make noise during operation, and that noise could potentially annoy occupants of the motorhome. By positioning the heating component on the outside of the motorhome, sound must travel through the coach body in order to reach the interior of the motorhome and any occupants therein. However, the coach body will have natural sound dampening characteristics, and additional sound insulation might be included inside the walls of the coach body, both of which will substantially dampen noise generated by the heating component. Therefore, positioning the heating component as such will significantly reduce the amount of heating component noise reaching the interior of the motorhome. These and other objects and advantages of the present invention will become more fully apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preassembled vehicle frame mounted on a preassembled chassis forming the framework for a motorhome with a high interior ceiling including an HVAC system with common air return;
FIG. 2 is a perspective view of an assembled heating, ventilation, and air-conditioning (HVAC) system; and
FIG. 3 is a side, section schematic view of a motorhome provided with the HVAC system of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made to the drawings wherein like numerals refer to like parts throughout. FIG. 1 shows an preassembled vehicle frame 100 mounted to a preassembled chassis 102 . The vehicle frame 100 , mounted to the chassis 102 in the manner that will be described in greater detail below, facilitates the construction of a motorhome 104 (FIG. 3) with a greater interior ceiling height, which in this embodiment, is at least 7′-6″ in a reduced time span. The vehicle frame 100 also facilitates mounting of relatively massive items, such as generators, furnaces, storage and holding tanks, and the like low to the ground so as to provide a lower center of mass for the motorhome 104 .
The vehicle frame 100 provides a strong three dimensional space frame 118 to inhibit twisting of the vehicle frame 100 under torsional forces such as would arise when the motorhome 104 drives over uneven terrain so as to lift or drop a wheel 116 with respect to the other wheels 116 . The vehicle frame 100 further defines integral storage areas 106 as part of the structure of the vehicle frame 100 in a manner that will be described in greater detail below. As shown in FIG. 1, the storage areas 106 are positioned below the beltline of the frame 100 and chassis 102 . Placement of the storage areas 106 low within the motorhome 104 also positions items that may be stored in the storage areas 106 low within the motorhome 104 . This aspect of the invention advantageously positions heavy cargo that users may place in the motorhome 104 low along the vertical extent of the motorhome 104 thereby maintaining an advantageously low center of mass.
The vehicle frame 100 further facilitates routing of a heating, ventilation, and air conditioning (HVAC) system 110 below the beltline of the frame 100 so as to avoid intrusion of the HVAC system 110 into the interior living space of the motorhome 104 to further enable increased interior ceiling height of the motorhome 104 employing the vehicle frame 100 . The HVAC system 110 comprises a furnace 164 and air conditioning unit 162 including evaporator, condenser, and compressor. These relatively heavy portions of the HVAC system 110 are installed below the beltline of the frame 100 thereby maintaining a lower center of gravity (c.g.) than other designs.
The chassis 102 also comprises a plurality of road wheels 116 with corresponding suspension, brake systems, steering, and drive mechanisms of types known in the art that are positioned at substantially the front and rear corners of the chassis 102 in the manner illustrated in FIG. 1 . The road wheels 116 enable the motorhome 104 to roll along the road and to be steered and braked in a well understood manner. The road wheels 116 are positioned adjacent the overlapping raised rails 112 and lower rails 114 . The chassis 102 further comprises an engine assembly, transmission, drive axle, fuel system, and electrical system (not illustrated) of types known in the art to provide the motive power for the motorhome 104 . These items are advantageously located substantially within the plane of the rails 112 to lower the center of mass of the chassis 102 and thus the motorhome 104 .
The chassis 102 of this embodiment is highly resistant to bending along longitudinal and transverse axes. However, the chassis 102 , by itself, is susceptible to twisting along the plane of the longitudinal and transverse axes due to torsional forces. Such torsional force may arise when a road wheel(s) 116 at one corner of the chassis 102 is displaced either above or below the plane of the remaining road wheels 116 . Additionally, the torque of the engine exerts a torsional force on the chassis 102 .
The motorhome 104 of this embodiment is assembled on and around the interconnected vehicle frame 100 and the chassis 102 . The motorhome 104 provides users with a vehicle having a variety of living spaces and amenities fitted within the motorhome 104 . It is expected that the partitioning of the interior living spaces and placement of interior amenities will vary depending on the needs of any particular application or customer.
The motorhome 104 also comprises a front loop 192 as shown in FIG. 1 . The loop 192 is a generally rectangular structure attached at the front of the motorhome 104 to the frame 100 . The loop 192 provides structural support for interior body assemblies in the driver's and front passenger's area as well as the front exterior bodywork of the motorhome 104 and the front windshield. The loop 192 is assembled from a plurality of elongate steel members via welding in a similar manner to that previously described with respect to the frame 100 .
The vehicle frame 100 also comprises seat supports 126 . The seat supports 126 are, in one embodiment, rectangular structures formed from sheet steel approximately ⅛″ thick and are approximately 12{fraction (13/16)}″ by 22½″. The seat supports 126 are fixedly attached to the vehicle frame 100 via a plurality of bolts and/or welding in a known manner adjacent the front end of the vehicle frame 100 . The seat supports 126 provide a support and attachment structure for passenger seats 128 of known types. The passenger seats 128 provide seating accommodations for driver and passengers in a known manner.
The HVAC system 110 in this embodiment comprises the air conditioning unit 162 , the furnace 164 , a manifold 166 , a duct 170 , at least one register 172 , an intake 171 , and a filter 173 as illustrated in FIG. 1 . The single (common) intake 171 (shown in section view in FIGS. 1 and 3) commonly directs air from the interior of the motorhome 104 to both the air conditioning unit 162 and the furnace 164 . The filter 173 is positioned within the intake 171 and filters the air entering the HVAC system 110 . The air conditioning unit 162 receives air from the interior of the motorhome 104 via the intake and cools this filtered incoming air and directs the cool air into the interior of the motorhome 104 via the manifold 166 , duct 170 and register(s) 172 . The furnace 164 warms incoming air and directs the warm air into the interior of the motorhome 104 also via the manifold 166 , duct 170 and register(s) 172 . The air-conditioning unit 162 , furnace 164 , and filter 173 are commercially available and the selection of an appropriate model of air-conditioning unit 162 , furnace 164 , and filter 173 is expected to vary depending on the size of and amount of insulation provided for a particular embodiment of motorhome 104 .
The manifold 166 receives air from both the air conditioning unit 162 and the furnace 164 and routes the air to the duct 170 . The duct 170 extends substantially the length of the interior of the motorhome 104 as shown in FIGS. 1 and 3. The duct 170 carries the warm or cool air to at least one register 172 . The registers 172 direct cool or warm air, received from the duct 170 , into the interior of the motorhome 104 . The registers 172 includes a screen to inhibit objects falling into the interior of the registers 172 and the duct 170 .
The common intake 171 is advantageously formed on two sides by adjoining first 180 and second 182 interior trim panels extending generally vertically that serve both to direct the air inside the intake 171 and also provide interior trim in the interior of the motorhome 104 . The other two sides of the intake 171 are formed by adjoining interior surfaces of the rear coach panel 184 and a side coach or structural panel 186 in a corner of the motorhome 104 . In one embodiment, the common intake 171 further comprises adjoining third 188 and fourth 190 trim panels which adjoin the rear coach panel 184 and a coach roof structural panel 140 respectively so as to define a generally horizontally extending box structure. Thus, the intake 171 is substantially defined by body structures 184 , 186 , and 140 of the motorhome 104 that simultaneously serve other structural or aesthetic functions thereby reducing material redundancy and effecting weight and material savings for the motorhome 104 . In addition, by directing air to both the air-conditioning unit 162 and the furnace 164 , the common intake 171 of this embodiment, obviates the need for the separate air intakes for the A/C unit and the furnace of other know designs.
The common intake 171 of this embodiment also facilitates the use of a single filter 173 for the HVAC system 110 . This single filter 173 reduces the time and expense of maintaining the HVAC system 110 by the end user as compared to other designs with multiple filters for the separate A/C and furnace systems. This commonality also reduces the time and expense of construction of the HVAC system 110 as well as reducing the weight thereof. In certain embodiments, the filter 173 can comprise a plurality of filter elements or stages, for example, a first filter element/stage adapted to remove larger air borne particles and a second filter element/stage adapted to remove smaller airborne particles that may pass through the first element/stage.
The HVAC system 110 , of this embodiment, is located within or below the plane of the chassis 102 . Positioning the air conditioning unit 162 and the furnace 164 , which are both relatively heavy items, within or below the plane of the chassis 102 further lowers the center of gravity of the motorhome 104 to thereby improve the road handling of the motorhome 104 . The placement of the HVAC system 110 of this embodiment also distances the duct 170 and registers 172 from the coach roof 140 . Other known motorhome designs rout HVAC ducting adjacent the roof of the vehicle which exposes the cool air to thermal heating from sunlight incident on the roof of the vehicle. In the motorhome 104 of this embodiment, the duct 170 , register 172 , and air conditioning unit 162 are shaded from incident sunlight by the motorhome 104 . Thus, the HVAC system 110 can more efficiently provide cool air to the interior of the motorhome 104 . This improves the occupant's comfort in hot weather and reduces fuel costs for powering the HVAC system 110 .
A further advantage of the HVAC system 110 of this embodiment is that the air conditioning unit 162 , duct 170 , and register 172 which carry cool air are located below the living space of the motorhome 104 . As is well understood by those of ordinary skill in the art, a cooler than ambient surface, such as the air conditioning unit 162 , duct 170 , and register 172 induces liquid water to condense out of the atmosphere if the temperature of the surface is at or below the dew point. When air conditioning ducting is routed above the living space of a motorhome, liquid water that condenses on the ducting is drawn downwards by gravity. This can induce liquid water to intrude into walls, ceilings, and other interior materials. It can be appreciated that liquid water can readily damage the structural integrity of typical motorhome building materials. Liquid water can also stain and warp interior materials, damaging the aesthetics of a motorhome. The air conditioning unit 162 , duct 170 , and registers 172 of this embodiment are positioned below the living space of the motorhome 104 and thus water that condenses out during use of the HVAC system 110 is drawn downwards and away from the motorhome 104 without intruding into the living spaces of the motorhome 104 .
An additional advantage of the HVAC system 110 of this embodiment is that placement of the HVAC system 110 adjacent and below the beltline of the chassis 102 obviates the need to place portions of an HVAC system on the roof of the motorhome 104 . Other known HVAC systems place portions of the system on the exterior roof of a motorhome. This requires that the major plane of the outer roof be lowered with respect to the roof of the present invention so as to maintain the overall height restrictions previously mentioned. Lowering the exterior roof height results in corresponding lowering of the interior ceiling height and a corresponding reduction in the interior space and livability of such a motorhome.
Yet another advantage of the HVAC system 110 of this embodiment is that placement of the HVAC system 110 adjacent and below the beltline of the chassis 102 distances the furnace 164 and air conditioning unit 162 from the interior of the motorhome 104 . The air conditioning unit 162 and furnace 164 are relatively noisy in operation. Placing the HVAC system 110 outside the interior of the motorhome 104 distances the noise sources of the air conditioning unit 162 and the furnace 164 and thus provides a quieter, more comfortable living environment for users of the motorhome 104 .
Although the preferred embodiments of the present invention have shown, described and pointed out the fundamental novel features of the invention as applied to those embodiments, it will be understood that various omissions, substitutions and changes in the form of the detail of the device illustrated may be made by those skilled in the art without departing from the spirit of the present invention. Consequently, the scope of the invention should not be limited to the foregoing description but is to be defined by the appended claims.
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A unitized heating, ventilation, and air conditioning (HVAC) system ventilates and regulates the air temperature inside a motorhome. Air is drawn from inside the motorhome and is directed to a furnace and an air conditioning unit via a common air return. A filter is positioned within the common return. The HVAC unit is compact and adapted for placement below the living area of motorhome so as to reduce the noise inside the cabin generated by the HVAC system and to reduce the center of gravity of the motorhome.
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BACKGROUND OF THE INVENTION
This invention relates to the processing of thin wafers, such as slices of semiconductor silicon and, more particularly, to improved method and apparatus for mounting of such thin slices on a carrier for performing of mechanical operations thereon, such as polishing of the wafers.
This invention constitutes an improvement of the inventions disclosed and claimed in Walsh U.S. Pat. Nos. 3,475,867 and 3,492,763.
The former discloses a method of wax mounting of semiconductor slices, e.g., silicon to a carrier plate having a flat surface. After the wafers have been mounted on the carrier plate, they are subjected to operations including washing, lapping, polishing, etc. The arrangement disclosed in the latter patent provides for the location of the wafers upon the carrier surface in a uniform arrangement to eliminate deleterious effects of random slice disposition.
When utilizing the methodology as described in the above-identified patents for the wax mounting of silicon wafers to carrier plates for further operations thereon, and particularly polishing to a high degree of surface perfection as appropriate for the manufacture of integrated circuits in such wafers, it has been observed that there is approximately a 10% incidence of air bubble entrapment in the wax layer under the slice, even though entrainment of air bubbles was sought to be avoided by the use of such prior art methodology. Such entrapment is believed to happen when, for example, the concave surface of a wafer which is bowed by virtue of strain therein resulting from sawing or other factors is placed in contact with the sticky wax layer which is first applied to the carrier plate. If the edges of the wafer, or slice, are, in effect "wetted" by the wax before all of the air is forced out from beneath it by the pressure applied against the wafer as it is pressed against the wax coating, then some air remains trapped beneath the slice i.e., between the wafer and adjacent surface of the carrier plate.
Such entrapped air bubbles are a matter of concern when the wafers must be polished to a state of extreme flatness. In the manufacture of very large scale integrated (VLSI) circuits, the density of circuit elements which must be created on a silicon wafer requires an extraordinarily high order of precision and resolution calling for wafer flatness heretofore not required. The necessary polished slice flatness for such applications (less than about 2 micrometers peak-to-valley) cannot be achieved if significant air bubbles are entrapped between a wafer and a carrier and are permitted to remain during polishing. Such bubbles provide a source of pressure tending to bow out a portion of the wafer over the bubble. Accordingly, the pressure exerted by the bubble during polishing results in a region which is polished under slightly greater pressure than portions of the wafer which do not have bubbles therebeneath. Consequently, the polished wafer has regions of thinness after polishing where the bubbles were present.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved method of wax mounting of thin wafers to a carrier for further operations thereon, and particularly for wax mounting of slices of semiconductor silicon or other crystalline materials useful in semiconductor and integrated circuit processing to permit polishing thereof.
It is another object of the present invention to provide a method of the character stated for use in wax mounting of such thin wafers and the like so as to substantially avoid the entrapment of air bubbles beneath the wafers.
It is a further object of the present invention to provide a method of the character stated permitting polishing of wafers to an extraordinarily high degree of flatness, such as conducive to the manufacture of VLSI circuits.
It is a still further object of the present invention to provide a method of the character stated which can be practiced simply and easily within the context of large scale, mass production manufacture and processing of wafers of monocrystalline semiconductor silicon and the like.
It is another object of the invention to provide a method of the character stated which can be practiced with a minimum of manual steps and which is amenable to automation.
It is a further object of the invention to provide apparatus for wax mounting of thin wafers of the type stated without entrapment of air bubbles beneath the wafers.
Other objects and features of the invention will be in part apparent and in part pointed out hereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of apparatus, illustrated partly in vertical cross-section, for carrying out a method of wax mounting of thin wafers to a carrier in accordance with the present invention.
FIG. 2 is a horizontal cross-section taken along line 2--2 of FIG. 1.
FIGS. 3 and 4 are views similar to FIG. 1 illustrating the apparatus as it is utilized for carrying out certain steps in the operation of the method of the invention.
FIG. 5 is a fragmentary view of portions of the apparatus of FIG. 1 and a carrier having wafers wax mounted thereon upon completion of the method of the invention.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, designated generally at A is apparatus for carrying out a method of wax mounting of thin wafers, such as so-called slices of monocrystalline semiconductor silicon to be utilized in the manufacture of VSLI circuits. However, wax mounting in accordance with the present invention is suitable for various other thin wafers, such as of germanium, sapphire or other crystalline materials, including garnets as well as various binary, trinary, quaternary, etc., or alloy compositions of rare earth metals and various elements, such as those of atomic groups of I-VII, II-VI or III-V series, or other crystals, compounds or alloys intended for electronics, optics and/or acoustics, etc., applications.
At 10 is designated a metal wafer support plate which is termed a carrier plate or disc-like configuration known in the art and to which it is intended to secure one or a plurality of such thin wafers by removably mounting the same by adherence to a coating 11 of wax upon a flat surface or face 12 of the carrier plate.
Such wax mounting of wafers permits them to be subjected to various processing operations including lapping, washing and, most notably, polishing. If said wafers are monocrystalline silicon slices, which may have a diameter of, for example, 125 mm, such lapping or polishing may be in accordance with Walsh et al., U.S. Pat. No. 3,170,273, to an extraordinarily high degree of surface perfection suitable for making VSLI circuits.
Wax coating 11 is applied in accordance with Walsh U.S. Pat. No. 3,475,867 utilizing a wax as described in Walsh U.S. Pat. No. 3,492,763, both herein incorporated by reference. Briefly, application of the coating is before heating of carrier plate 10 to a predetermined temperature. The wax is dissolved in a volatile solvent and is poured upon the surface 12 of carrier plate (with said surface facing up) while the carrier plate is rotated about its center, thereby to uniformly coat the surface with the wax to establish a reference plane of wax. The wax is maintained in a sticky condition by heat of the carrier plate, which remains heated sufficiently for this purpose while carrying out the new method.
For carrying out the new method, after being coated with wax layer 12, carrier plate 10 is placed within apparatus A with said plate inverted whereby wax coating 11 faces down as illustrated. However, before discussing those aspects of the method which characterize the invention, the features of apparatus A are here described.
A metal base plate 14 of relatively massive, stable character is provided, having a flat, smooth upper face 15 upon which is seated a metal layout plate 16 of disc-like configuration. A plurality of right cylindrical posts 18 spaced at even arcuate intervals around the center of plate 16 are secured to an upper surface or face 19 of plate 16 and extend upwardly therefrom. Each of said posts is identical, each thus having the same length and each being of a diameter which preferably is the same as that of a circular wafer to be wax mounted in accordance with the invention. Posts 18 are not in any event of smaller diameter or smaller cross-sectional area than the wafers to be wax mounted. There are, merely for purposes of illustration, assumed to be four such posts 18 in apparatus A but there may be but one post or several more than illustrated, e.g., six in all.
Secured atop each post 18 is a pad 20 of open-cell foam rubber, each said pad having the same circular cross-section of each post 18 and uniform thickness, e.g., about 13 mm. but being compressible by about 25%, i.e., 3-4 mm. when wafers are pressed against wax coating 11 as described hereinbelow. Hence, each pad 20 is resilient. Each post 18 is, in effect, a wafer pedestal and hence, the posts are referred to hereinbelow as pedestals.
Spaced above plate 16 and parallel therewith is a metal template or locator plate 22 of disc-like configuration and provided with a plurality of circular apertures 23 which correspond to pedestals 18 and are coaxial therewith, as shown in FIG. 2. The wafers W, when of silicon, are circular (except for a small crystallographic orientation flat) and typically are of 3 in. (76.2 mm.), 100 mm. or 125 mm. diameter. The circular pads 25 are of corresponding diameter, while the circular apertures 23 are of correspondingly slightly larger (by about 1.25 mm.) diameter.
Template 22 is supported upon a plurality of springs 25 of spring constant sufficient for the springs to support the weight of template 22 and carrier plate 10 such that the upper surface of each of pads 25 will be at or slightly above the level of the lower surface 26 of template 22 whereby circular wafers W (FIG. 3) will be located by apertures 23 and by template 22 in substantial alignment with pedestals 18 with the wafers seated upon pads 20 and thus resiliently supported by the pedestals across their entire surface area of a front face of each wafer as compared with a prior art arrangement supporting each wafer only across a portion (of about one-half to two-thirds of the diameter) of the frontal surface of the wafer.
Carried upon the upper surface 28 of template 22 are a plurality of contact points or pins 29 which may simply be the pointed tips of screws threaded into template 22. Said points 29 are spaced at even intervals around the periphery of the template.
Three of points 29 are shown merely for illustrative purposes, but a lesser or greater number may be used. The purpose of said points 29 is to support carrier plate 10 by engagement of its surface 12 without disturbing wax coating 11 except at the actual point of contact therewith. Carrier plate 10 is thus intended to be supported concentric with, and parallel to, layout plate 16 and template 22 with the sticky wax coating facing the backside of each of the wafers W seated upon pads 20 within apertures 23. By backside is meant the wafer face to be adherent to the carrier so that the opposite face may be lapped, polished, etc., although conceivably the backside itself may previously or subsequently be lapped, polished, etc., or otherwise treated.
Indicated at 30 is an enclosure or cover having four side walls 31 and an upper wall 32 closing the top entirely, said enclosure being open at the bottom but with the side walls all being provided with a continuous O-ring seal 34 along the lower edge and adapted to lie snug against the upper surface 15 of base plate 14. Enclosure 30 is adapted to provide an air tight chamber when seal 34 bears against surface 15. The space of the enclosure is not critical as long as it encloses the various above-described elements.
Carried by the enclosure upper wall 32 is a pneumatic cylinder 36 having a piston 37 therein to which an actuator rod 38 is secured, said cylinder being interconnected by air lines 39, 39' having valves 40, 40' therein for controlling the admission of air under pressure to the cylinder on opposite sides of the piston for movement of the piston either up or down, providing corresponding movement of actuator rod 38.
Cylinder 36 is oriented for movement of actuator rod 38 normal to carrier plate. Carried at the lower end of actuator rod 38 is a circular pressure plate 42 having on its bottom surface a foam pad 43. Said plate 42 is perpendicular to rod 38 and is thus parallel to carrier plate 10, and preferably has diameter less than that of the carrier plate. Pad 43 may be of annular configuration whereby upon lowering of pressure plate 42 by movement of piston 37, pressure can be applied to carrier plate 10 over a cross-sectional area of annular configuration and generally coinciding with the pattern of apertures 23.
Although preventing carrier plate 10 from being damaged by pressure plate 42 and assisting in even distribution of pressure, pad 43 primarily serves to provide thermal insulation between the carrier plate and pressure plate 42 whereby the carrier plate is not cooled by pressure plate 42 when pressed downwardly thereby.
Enclosure 30 is adapted to be raised and lowered manually or by any suitable mechanical arrangement, so as to facilitate use in production line processing of wafers. When lowered in sealing relationship with base plate 14, the enclosure is of sufficient strength and air-tight character as to permit evacuation to less than 1 torr (1 mm. Hg pressure). For that purpose, a vacuum line 45 is connected between a passage 45' within base plate 14 and a vacuum pump 46, driven by an electric motor 47, through a valve 48. A further valve 49 is adapted for venting line 45 to atmospheric pressure.
For carrying out a method of wax mounting of wafers in accordance with the invention, enclosure 30 is opened and wafers W are placed upon the pedestal pads 20 within template apertures 23, as depicted in FIG. 3, by use of a vacuum pencil. The heated, carrier plate 10, which may be a conventional polishing block of stainless steel heated to about 100° C. and having been given wax coating 11 as described in said U.S. Pat. No. 3,475,867, is then immediately placed upon contact points 29, being located as described above, by suitable handling or supporting means (not shown). Enclosure 30 is then lowered upon base plate 14 with seat 34 in sealing contact with surface 15 thereof. Piston 37 is in the position shown in FIG. 3 so that pressure plate 42 is not in contact with carrier plate 10. Valve 49 is then closed and valve 48 is opened. Pump 46 is then operated to evacuate the interior of enclosure 30, which thus defines a vacuum chamber 50 for the carrier plate to a predetermined fraction of normal atmospheric pressure which will eliminate air bubbles beneath the wafers or reduce them to an acceptably insubstantial size or degree.
Broadly, the chamber is evacuated to about 0.1 to about 200 torr, but more narrowly preferred, from about 1-10 torr, as indicated by a suitable gauging device 51. A specific pressure of 1 torr is mot preferred.
While maintaining such relative vacuum, air is admitted to pneumatic cylinder 36 through valve 40 to cause pressure plate 42 to be lowered, by movement of piston 37, against carrier plate 10, the pressure in cylinder 36 being sufficient to cause compression of springs 25. Carrier plate 10 is moved downward by the force by pressure plate 42 until wafers W come in contact with wax coating 11, which remains sticky because of the heat stored in the carrier plate. The force exerted by pressure plate 42 is sufficient to press carrier plate 10, if such is a wafer polishing block, against the wafers, where such are silicon slices as described above, with a force of about 10 lbs./in. 2 , of slice or wafer area. Such pressure may range from about 2 to about 30 lb/in. 2 of wafer area but must in any event be adequate to force or distort the wafers (which may typically have a slightly bowed character resulting from strain during slicing, etc., as previously noted) sufficiently to cause them to assume the flatness of the reference plane established by the wax coating.
At this time, the relationship shown in FIG. 4 obtains, and it is noted that pedestal pads 20 are thus compressed to resiliently seat or mount the wafers upon the wax-coated carrier plate, the slices or wafers W adhering to the sticky wax coating 11 in the manner described in said U.S. Pat. No. 3,475,867, whereby any foreign particles such as dust particles do not interfere with mounting of the wafers.
After maintaining pressure for a brief interval, e.g., preferably about 5 seconds, and more broadly from about 1 to about 10 seconds, air is admitted to pneumatic cylinder 36 through valve 40' to raise pressure plate 42. Valve 48 is closed and valve 49 is opened to vent chamber 50 and return it to normal atmospheric pressure. Enclosure is then lifted. Carrier plate 10 with the now wax-mounted wafers W is then raised, as shown in FIG. 5, by suitable handling or supporting means for being removed and transferred to another position for polishing or other processing of the wafers.
The following example illustrates the results of the invention:
EXAMPLE
Several hundred diamond-sliced, lapped and acid-etched silicon wafers of conventional sizes, 3 in. and 100 mm. diameter, are polished after wax mounting in accordance with the present method and evaluated for P/V (peak-to-valley) flatness by conventional technique. They are compared with identical wafers which are wax-mounted in accordance with the prior art method described in U.S. Pat. No. 3,492,763. The P/V flatness (worst case) results are summarized and compared as follows:
______________________________________ .sup.-- X 95% ≦ μm μm______________________________________3 in. wafersPrior art method 3.2 6.6Method of invention 1.3 2.0100 mm. wafersPrior art method 4.1 6.7(simulated)Method of invention 1.6 2.6______________________________________
In the table, X refers to the means of all wafers and 95%≦ refers to the maximum P/V flatness value of 95% of the wafers evaluated. By "simulated" is meant that said prior art method of U.S. Pat. No. 3,492,763 is simulated by utilizing apparatus A of the present disclosure to wax-mount the wafers without use of enclosure 30 to establish a relative vacuum and wherein the contacting of wafers W seated upon pedestal pads was effected by use of pressure plate 42. The term P/V flatness is defined as the sum of the greatest positive and negative deviations from a reference plane which approximates the median wafer surface plane when the wafer is mounted on an optically flat vacuum chuck but excluding a small peripheral marginal portion of 1-2 mm. width in order to exclude from the measurement the effect of the desirably edge-rounded character of the wafer.
Although the foregoing includes a description of the best mode contemplated for carrying out the invention, various modifications are contemplated.
As various modifications could be made in the method and constructions herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting.
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Apparatus and method for wax mounting of thin wafers such as slices of semiconductor silicon to a carrier for polishing wherein the carrier is heated after being coated with wax which is maintained in a sticky condition by the heated carrier. A chamber is utilized for enclosing the thin wafers on resilient supports with the sticky wax-coated, heated carrier disposed above them. The chamber has an air tight seal permitting it to be evacuated. After evacuation a pneumatic cylinder is utilized to press the carrier against the wafers, which adhere to the sticky wax coating. The chamber is vented then to atmospheric pressure, the wafers remaining mounted by the wax coating to the carrier for subsequent polishing. The method avoids entrapment of gas bubbles between wafers and carrier.
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BACKGROUND OF THE INVENTION
Modern elevator apparatus used in buildings primarily comprise rails, counterweights, safety devices, a signal control system, elevator car, elevator doors and other components. Elevators are installed in shafts, usually adjacent to or connected to the machine room of a building.
Many modern elevators are operated by a traction drive, wherein at least one cable has one end connected to the elevator car, is held in position by a traction sheave, and has the other end of the cables connected to the counterweight. Usually, the elevator is then operated by a motor coupled to the traction sheave, which raises or lowers the elevator.
Elevators design requires high transmission efficiency between the motor, the traction shave, and the cable. The basic design goals for modern elevators require the elevator to be energy efficient, safe, and accurately find each level. Elevators are designed around a rated load, a maximum speed, outer dimensions, and the size of the elevator shaft.
Passenger elevators also need to be intelligently controlled, often by computers such that people can use the elevators without the assistance of a specialized operator. Conventional elevator design also requires users to choose their floors once they have stepped inside the elevator, which can be inefficient. Furthermore, the energy efficiency of elevators can be further increased.
BRIEF SUMMARY OF THE INVENTION
It is an object of the invention to provide a variable mass elevator apparatus with an external control and a method of operation thereof.
According to an embodiment of the present invention, a variable mass elevator apparatus with an external control is provided, wherein the variable mass elevator apparatus with an external control comprises an electronic scale, an elevator car, a traction sheave, a control computer, a mass storage area, a mass, a mass conveyor, a floor control panel, and an elevator door.
The present invention provides an elevator car disposed in an elevator shaft coupled to a control computer. The elevator car is coupled to a cable and the cable goes around a traction sheave disposed at the top of the elevator shaft. An electronic scale is disposed outside of the elevator shaft, such that an elevator passenger has to step on the electronic scale prior to stepping into the elevator. Disposed outside of the elevator shaft is a floor control panel. The electronic scale is coupled to the control computer. On the opposite side of the elevator shaft from the elevator door, a mass storage area is disposed on each floor of the building with an attached mass conveyer. Within the mass storage areas are masses. The control computer is connected to the mass conveyer.
When a passenger desires to operate the elevator, the passenger steps on the electronic scale and chooses a floor on the floor control panel, wherein the floor control panel has buttons for each floor. The electronic scale relays the weight of the passenger to the control computer, and the floor control panel relays the desired floor to the control computer.
The control computer upon receiving the desired floor and the weight of the passenger will send a signal to the traction sheave and motor coupled to said traction sheave to move the elevator car to the floor that the passenger is on and stop the elevator at that floor. The elevator door will open once at the floor the passenger is on. Once the elevator car has arrived at the passenger's floor, the control computer will signal to the mass conveyer to move a mass from the mass storage area corresponding to the mass of the passenger to couple with the elevator cable and act as a counterweight to the elevator car and passenger.
The passenger, once inside the elevator car, will have his or her potential energy matched by the counterweight mass that the mass conveyer has coupled to the elevator cable. For instance, if the passenger weighs 50 kg, the mass conveyer will move five 10 kg mass units to be coupled to the elevator cable. By adjusting the mass of the counterweight to match the weight of the passenger, the potential energy of the weight of the passenger suspended by the elevator will be effectively countered by the potential energy of the mass coupled to the elevator cable as a counterweight. By variably adjusting the mass of the counterweight to match the weight of the passenger, the elevator car can then be moved by the traction sheave coupled to the motor with less energy.
The elevator car will then be moved to the desired floor where the elevator door will open to allow the passenger to exit. Once the elevator car has arrived at the desired floor, the control computer will relay to the conveyer at the desired floor to remove the mass from the elevator cable into the mass storage area of the desired floor.
The above embodiment of the present invention allows for users to pre-select a desired floor, thus saving the user time from having to call an elevator and subsequently select a floor from inside the elevator car, and the adjusted variable mass counterweight will significantly reduce the required energy to move the elevator.
It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The above embodiments become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which:
FIG. 1 is a schematic diagram of the variable mass elevator apparatus and external control;
FIG. 2 is a schematic diagram from an entrance-side of the variable mass elevator apparatus and external control;
FIG. 3 is a schematic diagram of the variable mass elevator apparatus and external control when the weight of the passenger is 50 kg, the starting floor is the first floor, the desired floor is the fifth floor, and the elevator car is on the first floor;
FIG. 4 is a schematic diagram of the variable mass elevator apparatus and external control when the weight of the passenger is 50 kg, the starting floor is the first floor, the desired floor is the fifth floor, and the elevator car is on the fifth floor;
FIG. 5 is a schematic diagram from an entrance-side of the variable mass elevator apparatus and external control when there are two passengers, the weights of the passengers are 30 kg and 70 kg, the starting floor is the first floor, the desired floors are the second and fifth floors, and the elevator car is on the first floor;
FIG. 6 is a schematic diagram from an entrance-side of the variable mass elevator apparatus and external control when there are two passengers, the weights of the passengers are 30 kg and 70 kg, the starting floor is the first floor, the desired floors are the second and fifth floors, and the elevator car is on the second floor;
FIG. 7 is a schematic diagram from an entrance-side of the variable mass elevator apparatus and external control when there are two passengers, the weights of the passengers are 30 kg and 70 kg, the starting floor is the first floor, the desired floors are the second and fifth floors, and the elevator car is on the fifth floor.
DETAILED DESCRIPTION
Aspects, features and advantages of several exemplary embodiments of the present invention will become better understood with regard to the following description in connection with the accompanying drawings. It should be apparent to those skilled in the art that the described embodiments of the present invention provided herein are illustrative only and not limiting, having been presented by way of example only. All features disclosed in this description may be replaced by alternative features serving the same or similar purpose, unless expressly stated otherwise. Therefore, numerous other embodiments of the modifications thereof are contemplated as falling within the scope of the present invention as defined herein and equivalents thereto. Hence, use of absolute terms, such as, for example, “will,” “will not,” “shall,” “shall not” “must,” and “must not,” are not meant to limit the scope of the present invention as the embodiments disclosed herein are merely exemplary.
FIG. 1 is an exemplary embodiment of the variable mass elevator apparatus and external control, comprising electronic scale 1 , an elevator car 2 , a traction sheave coupled to a motor 3 , a control computer 4 , a mass storage area 5 , a mass 6 , and a mass conveyor 7 . The elevator car 2 is disposed in an elevator shaft and coupled to an elevator cable disposed about the traction sheave 3 . The traction sheave 3 is coupled to the control computer 4 . The control computer is also coupled to the electronic scale 1 disposed in front of the entrance to the elevator on each floor.
In this embodiment, the traction sheave 3 is coupled to an electric motor. Those of ordinary skill in the art will recognize that other means of powering the traction sheave can be used, like hydraulic or pneumatic power.
On the opposite side of the elevator shaft from the elevator car door side, a mass storage area 5 is disposed next to the elevator shaft on each floor and coupled to the mass conveyer 7 . The mass conveyer 7 of each floor is coupled to the control computer to receive a signal to move a mass 6 to be coupled to the elevator cable according to the weight of the passenger relayed via the control computer 4 . The electronic scale 1 is configured to relay the weight of the passenger to the control computer 4 via a signal line.
The control computer 4 controls the traction sheave 3 via signal line and controls the motor of the traction sheave 3 to move the elevator car 2 according to the user selection. The control computer 4 receives the weight of the user when the user is standing on the electronic scale 1 disposed in front of the entrance to the elevator. When the user selects a desired floor, the control computer 4 moves the elevator car 2 using the traction sheave 3 to the user's starting floor. Once the elevator car 2 has arrived at the user's starting floor, the control computer 4 controls the mass conveyer 7 to move a mass 6 from the mass storage area 5 corresponding to the weight of the passenger to be coupled to the elevator cable to act as a counterweight to the weight of the passenger.
Once the user has stepped inside the elevator car, the control computer 4 will instruct the traction sheave 3 to move the elevator car 2 to the desired floor. Once at the desired floor, the elevator car 2 will open its doors and allow the user to exit. The control computer 4 will signal to the mass conveyer 7 of the desired floor to move the mass 6 from the elevator cable and into the mass storage area 5 of the desired floor.
By moving the mass 6 to be used as a counterweight to the weight of the passenger, the present invention reduces the amount of energy required by the traction sheave 3 to move the elevator car 2 . The control computer 4 instructs the mass conveyer 7 to move a mass 6 corresponding to the weight of the passenger to substantially counteract the potential energy of the passenger once inside the suspended elevator car 2 . If the passenger weighs 50 kg, the mass 6 can be five 10 kg mass units. The mass 6 can comprise a number of fixed mass units. In FIG. 1 , each mass unit is 10 kg.
FIG. 2 is an exemplary embodiment of the entrance side of the variable mass elevator apparatus and external control, comprising an electronic scale 1 , a floor control panel 8 , and the elevator door 9 . In this embodiment, the electronic scale 1 is disposed outside of the elevator door 9 , and directly in front of the floor control panel 8 , such that the user must step on the electronic scale 1 in order to input a desired floor into the floor control panel 8 . In the present embodiment, the floor control panel 8 has a button for each floor that the elevator car can go to. The electronic scale 1 and floor control panel 8 are both coupled to the control computer via a signal line. When the user selects a floor on the floor control panel 8 , the floor control panel 8 relays the desired floor information to the control computer. As the user is inputting the desired floor, the electronic scale 1 is weighing the user and relaying the weight of the user to the control computer. The control computer associates the weight of the passenger to the desired floor, such that each inputted desired floor instruction is associated with the weight of the passenger.
When two passengers wish to use the elevator, the first passenger steps on the electronic scale 1 , and chooses a first desired floor on the floor control panel 8 . The electronic scale 1 sends the weight of the first passenger to the control computer and the floor control panel 8 sends the first passenger's desired floor to the control computer. The control computer associates the first passenger's desired floor to the first passenger's weight.
The second passenger then steps on the electronic scale 1 , and chooses a second desired floor on the floor control panel 8 . The electronic scale 1 sends the weight of the second passenger to the control computer and the floor control panel 8 sends the second passenger's desired floor to the control computer. The control computer associates the second passenger's desired floor to the second passenger's weight.
FIG. 3 is an embodiment of FIG. 1 , when the passenger has selected the fifth floor as the desired floor, and the passenger has stepped into the elevator car 2 on the first floor. The passenger weighs 50 kg.
On the opposite side of the elevator shaft from the elevator car door side, a mass storage area 5 is disposed next to the elevator shaft on each floor and coupled to the mass conveyer 7 . The mass conveyer 7 of each floor is coupled to the control computer to receive a signal to move a mass 6 to be coupled to the elevator cable according to the weight of the passenger relayed via the control computer 4 . The electronic scale 1 is configured to relay the weight of the passenger to the control computer 4 via a signal line.
The control computer 4 controls the traction sheave 3 via signal line and controls the motor of the traction sheave 3 to move the elevator car 2 according to the user selection. The control computer 4 receives the weight of the user when the user is standing on the electronic scale 1 disposed in front of the entrance to the elevator. When the user selects a desired floor, the control computer 4 moves the elevator car 2 using the traction sheave 3 to the user's starting floor. Once the elevator car 2 has arrived at the user's starting floor, the control computer 4 controls the mass conveyer 7 to move a mass 6 from the mass storage area 5 of the desired floor corresponding to the weight of the passenger to be coupled to the elevator cable to act as a counterweight to the weight of the passenger.
Once the user has stepped inside the elevator car, the control computer 4 will instruct the traction sheave 3 to move the elevator car 2 to the desired floor. Once at the desired floor, the elevator car 2 will open its doors and allow the user to exit. The control computer 4 will signal to the mass conveyer 7 of the desired floor to move the mass 6 from the elevator cable and into the mass storage area 5 of the desired floor.
By moving the mass 6 to be used as a counterweight to the weight of the passenger, the present invention reduces the amount of energy required by the traction sheave 3 to move the elevator car 2 . The control computer 4 instructs the mass conveyer 7 to move a mass 6 corresponding to the weight of the passenger to substantially counteract the potential energy of the passenger once inside the suspended elevator car 2 . In this embodiment, the passenger weighs 50 kg and the mass 6 is five 10 kg mass units. The mass 6 can comprise a number of fixed mass units. The mass 6 is moved by the mass conveyer 7 on the desired floor (the fifth floor). By moving the mass 6 to be coupled to the elevator cable to act as a counterweight from the fifth floor, the control computer 4 is matching the change in potential energy of the weight of the passenger. In FIG. 3 , each mass unit is 10 kg. Once the passenger is inside the elevator car 2 , the control computer 4 signals to the traction sheave 3 to begin moving the elevator car 2 to the desired floor.
FIG. 4 is a schematic diagram of the embodiment of FIG. 3 , when the elevator car 2 has arrived at the desired floor of the passenger. The control computer 4 signals to the traction sheave 3 to stop the elevator car 2 at the desired floor. When the elevator car 2 has arrived at the desired floor, the control computer 4 signals to the mass conveyer 7 to remove the mass 6 coupled to the elevator cable, and the mass conveyer 7 moves the mass 6 to the mass storage area 5 on the desired floor.
FIG. 5 is an embodiment of FIG. 1 , when there are two passengers in the elevator car 2 , and the passengers weigh 70 kg and 30 kg, respectively. The starting floor is the first floor for the elevator car 2 , and the desired floors are the second and fifth floors. The first passenger weighing 70 kg selected the fifth floor while standing on the electronic scale 1 . The electronic scale 1 relays the weight of the first passenger and the floor control panel relays the desired floor to the control computer 4 . The control computer 4 associates the first passenger's weight with the desired fifth floor. The second passenger weighing 30 kg selected the second floor while standing on the electronic scale 1 . The electronic scale 1 relays weight of the second passenger to the control computer 4 and the floor control panel relays the second passenger's desired floor to the control computer 4 . The control computer 4 associates the weight of the second passenger to the desired second floor. Similar to FIG. 3 , the control computer 4 has instructed the mass conveyer 7 on the second and fifth floor to move a first mass 6 on the fifth floor and a second mass on the second floor to be coupled to the elevator cable. The first mass 6 is 70 kg, or seven 10 kg mass units. The second mass is 30 kg, or three 10 kg mass units. The potential energy of first passenger is matched to the first mass 6 attached to the elevator cable at the fifth floor and the potential energy of the second passenger is matched to the second mass attached to the elevator cable at the second floor.
The control computer 4 then instructs the traction sheave 3 to begin moving the elevator car 2 once the mass 6 matches the weight of the passengers and the passengers are inside the elevator car 2 .
FIG. 6 is a schematic diagram of the embodiment of FIG. 5 , when the elevator car 2 has been moved by the traction sheave 3 to the second floor. The traction sheave 3 stops the elevator car 2 at the second floor allowing the second passenger to depart. The control computer 4 instructs the mass conveyer to remove the second mass from the elevator cable and move the second mass into the mass storage area of the second floor. Once the second passenger has departed and the second mass has been removed by the mass conveyer, the potential energy of the passengers in the car is once again matched to the potential energy of the suspended counterweight. The control computer 4 then instructs the traction sheave 3 to begin moving the elevator car 2 to the first passenger's desired floor.
FIG. 7 is a schematic diagram of the embodiment of FIG. 5 , when the elevator car 2 has been moved by the traction sheave 3 to the fifth floor, or the first passenger's desired floor. The traction sheave 3 stops the elevator car 2 at the first passenger's desired floor, and the control computer 4 instructs the mass conveyer to remove the first mass from the elevator cable, resetting the potential energy of the counterweight to match an empty elevator car 2 , once the first passenger departs.
The foregoing description of the preferred embodiments is presented for purposes of illustration and description. It is not intended to be exhaustive or limit the invention to the precise form of the exemplary embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are chosen and described in order to best explain the principles of the invention and its best mode practical application, thereby to enable persons skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the invention”, “the present invention” or the like does not necessarily limit the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the invention does not imply a limitation on the invention, and no such limitation is to be inferred. The invention is limited only by the spirit and scope of the appended claims.
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The present invention provides a variable mass elevator apparatus and method of operation, wherein the apparatus comprises an electronic scale, an elevator car, a traction sheave, a control computer, a mass storage area, a mass, a mass conveyor, a floor control panel outside of the elevator. When a passenger desires to operate the elevator, the passenger steps on the electronic scale and chooses a floor on the floor control panel, wherein the floor control panel has buttons for each floor. The electronic scale relays the weight of the passenger to the control computer, and the floor control panel relays the desired floor to the control computer. The control computer instructs a mass conveyer to couple a mass corresponding to the weight of the passenger to the elevator cable to act as a counterweight and equalize the potential energy of the elevator according to the desired floor of the passenger and the weight of the passenger.
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BACKGROUND
The present invention relates to an infant care apparatus and, more particularly, to an infant warming apparatus having an overhead radiant heater and a pivotable canopy that is positioned over an infant.
In the care of newborn infants, there are various types of apparatus that provide heat to an infant and such apparatus can include infant incubators, infant warmers and combinations of the two. In such apparatus, there is normally provided, an infant platform on which the infant is positioned so as to receive the care and that infant platform is a generally planar surface located so as to underlie the infant. With infant warmers, there is also an overhead radiant heater that can be energized to direct energy in the infrared spectrum toward an infant resting on the infant platform to warm the infant.
In certain infant apparatus, there is also provided an infant compartment that encloses the infant and which can thereby form an enclosed area where the infant can reside within a controlled atmosphere where heat and possibly humidity are controlled so as to create a beneficial atmosphere for the wellbeing of the infant. That infant compartment is formed by the presence of a canopy located above the infant and which thereby encloses the infant resting on the infant platform.
An infant warmer is shown and described in U.S. Pat. No. 5,474,517 of Falk et al as prior art to that patent; an infant incubator is shown and described in U.S. Pat. No. 4,936,824 of Mackin et al and a combination apparatus that combines the functions of both an infant warmer and an infant incubator is shown and described in U.S. Pat. No. 6,224,539 of Jones et al.
As a further apparatus for caring for an infant, there can be a fixed heater mounted above the infant platform along with a movable canopy such as is shown and described in pending U.S. patent application Ser. No. 10/672,948 of Falk et al and entitled “Infant Care Apparatus With Fixed Overhead Heater” and the disclosure thereof is hereby incorporated herein in its entirety by reference. With that latter apparatus, there is a moving canopy however, the radiant heater itself is maintained in a fixed location.
One problem with the use of a canopy covering the infant to form the infant compartment, however, is that there are, obviously, times that the canopy must be opened in order to access the infant or to insert or remove the infant from that infant compartment. Therefore, there must be some means by which the canopy can be moved between a closed position where the infant compartment encloses the infant to an open position where the infant is accessible to carry out an intervention or procedure on that infant.
Accordingly, one convenient method that can be provided to allow the movement of the canopy between open and closed positions is by pivoting the canopy, preferable at one of its shorter ends of the generally rectangular footprint configuration and normally at the end that is herein defined to be the north end of the apparatus, that is, the end where there is normally located the various controls and monitors that are employed in carrying out the functioning of the apparatus and which is the end of the apparatus where the infant's head is conventionally located during the employment of the infant warming apparatus.
A difficulty arises, however, in pivoting the canopy at one end thereof between an open and a closed position is that there is often an overhead obstruction that is located above the infant platform such that the pivoting of the canopy about its north end is inhibited since the longer dimension of the canopy causes the canopy to encounter or hit the obstruction when the canopy is pivoted upwardly. With the apparatus described in the aforementioned patents and pending patent application, that overhead obstruction is the radiant heater that provides heat to the infant when located on that infant platform.
As such, therefore, the normal solid or one piece canopy cannot be readily opened with a pivoting motion about one of its shorter ends, since that canopy will physically encounter that obstruction and thus will be prevented from opening sufficiently to allow full access to the infant or to allow the apparatus to employ an overhead radiant heater to warm the infant.
It would, therefore be advantageous to have an infant care apparatus utilizing a canopy that is designed to be opened and closed, by pivoting about one end, where the canopy is specially constructed to function in the presence of a fixed overhead obstruction and yet which can be pivoted between open and closed positions without the obstruction unduly limiting the opening movement.
It would be further advantageous if that infant care apparatus were an infant warmer apparatus and the obstruction were the radiant heater used with that apparatus to provide heat to the infant.
SUMMARY OF THE INVENTION
Accordingly, the present invention relates to an infant care apparatus, such as an infant warming apparatus, that includes a base with an infant platform on the base for providing a support for an infant receiving care.
There is a canopy that is positioned atop of the infant platform and which is pivotally affixed with respect to the infant platform so that the canopy can be pivotally raised and lowered between, respectively, an open position and a closed position. There is also a radiant heater that is located at one end of the infant platform of the infant warming apparatus and which directs radiation in the infrared spectrum toward the infant platform to warm the infant when lying on that infant platform.
The pivot axis of the canopy is located at or proximate to the end of the infant platform where the radiant heater is located such that the other opposite end of the canopy can be raised and lowered about that pivot axis to move the canopy respectively, between its open and its closed positions. In the open position of the canopy, the caregiver has full access to the infant and also, the radiant heater can be energized to direct the radiant heat toward the infant on the infant platform. In the closed position the infant is enclosed within an infant compartment and heat and possible humidity controlled by a convective heating system.
With the present infant care apparatus, however, there is a specially designed canopy where an open space or opening can be created prior to or as the canopy is being raised from its closed position to its open position and that open space is dimensioned and oriented so as to align with the radiant heater, or other obstruction, that the canopy would otherwise encounter in pivoting the canopy upwardly to its open position. Thus, when the canopy is pivoted to its open position, the open space allows the canopy to be pivoted at least to, and preferably past, that radiant heater so that the radiant heater can direct the radiant energy toward the infant platform unobstructed by the canopy.
The creation of the open space in the canopy is accomplished by the construction of a canopy having two sections, that is, a first section and a second section. The first section is pivotally affixed to the infant care apparatus at a pivot axis that is fixed with respect to the infant platform and the second section is movable relative to the first section to form the opening or open space.
In one embodiment, the second section is slideably affixed to the first section such that the overall length of the canopy is reduced by sliding at least a portion of the second section to nest beneath the first section. That reduction in length allows the canopy to be pivotally raised such that the open space created by the shortened canopy is aligned with the radiant heater so that the canopy can be pivoted to, and preferably past, the radiant heater so that the radiant energy can be directed from the radiant heater to the infant platform without passing through the material of the canopy.
In essence, by moving the second section with respect to the first section, thereby creating an open space, the canopy can be pivotally raised so as to move past the radiant heater since the radiant heater is aligned with the open space, which was originally occupied by the second section, and thus clear the radiant heater so that the infrared energy can pass directly to the infant platform to warm an infant positioned thereon.
In another embodiment, the second section takes the form of a trap door that is hingedly affixed to the first section and is biased toward a closed position. Thus, when the canopy is pivoted to its open position, the biased trap door encounters the radiant heater such that further movement of the canopy causes the radiant heater to push the trap door open and thereafter extend through the opening thereby formed in the canopy. Again, therefore, due to the relative movement of the second section with respect to the first section, the radiant energy from the radiant heater can pass directly to the infant platform to heat an infant positioned thereon without passing through the material comprising the canopy.
With either embodiment, the canopy can be manually moved between its open and closed positions or, alternatively, may be powered by some motive means such as a motor, and in the embodiment utilizing the trap door, that trap door can also alternatively be opened and closed by a motive means such as a motor.
These and other features and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an infant care apparatus incorporating the present invention and showing the canopy in its closed position;
FIG. 2 is a side view of the infant care apparatus of FIG. 1 showing the canopy configured to be moved to its open position;
FIG. 3 is a side view of the infant care apparatus of FIG. 1 with the canopy moved to its open position;
FIG. 4 is a side view of an alternative embodiment of the infant care apparatus incorporating the present invention and showing the canopy in its closed position; and
FIG. 5 is a side view of the infant care apparatus of FIG. 4 with the canopy moved to its open position.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1 , there is shown a side view of an infant care apparatus 10 constructed in accordance with the present invention having a canopy 12 located in its lower or closed position. In the position of the canopy 12 , as shown, the infant care apparatus 10 acts as an infant incubator with relatively limited access to the infant, as compared to an infant warmer but with a controlled environment where the temperature and possibly the humidity and/or oxygen concentration is established and carefully maintained for the wellbeing of the infant.
As shown, the infant care apparatus 10 includes an infant platform 14 that underlies and supports an infant. As is also seen, a plurality of walls 16 are provided to contain the infant safely within the infant care apparatus 10 and are located at all of the four sides of the infant platform 14 . The walls 16 are preferable constructed of transparent plastic material and, as will be explained, cooperate with other components in order to provide an incubator function when the infant care apparatus 10 is in the FIG. 1 configuration.
A convective heating system can be used with the present invention and can be a well known commercially system that uses forced convective air and one such system that can be used is shown and described in U.S. Pat. No. 6,213,936 of Mackin et al and the necessary apparatus for the convection heating system, such as a heater, fan, humidity control, air ducts and the like are normally located within the infant platform. The convective heating system circulates the heated air through the infant compartment that is formed when the present canopy 12 is in its closed position and the infant care apparatus 10 is carrying out the function of an incubator.
The infant platform 14 is mounted to a vertical base member 18 which, in the preferred embodiment, is movably affixed to a stationary base member 19 which in turn, is mounted to a base 20 having wheels 22 for ready movement of the infant care apparatus 10 .
The vertical base member 18 is preferable mounted so that the user can adjust the height of the infant platform 14 by raising and lowering the vertical base member 18 as desired, thus the infant platform 14 can be adjusted to the preferred height by the user. As further standard features, the walls 16 have handholes 24 to afford access to the infant when in the incubator configuration of FIG. 1 , and which generally have doors 26 and/or the walls 16 , themselves, act as doors that can be opened to obtain access to the infant and, of course, closed when the particular intervention as been completed to preserve the desired environment surrounding the infant.
Another convenient feature includes a drawer 28 to retain supplies or other devices needed to carry out some operation on the infant and which is normally located beneath the infant platform 14 . Other features include the maneuverability of the walls 16 that are pivotally mounted at their bases to the infant platform 14 such that the walls 16 can be swung outwardly and downwardly and as a further alternative, can be easily fully removed from the infant platform 14 .
As such, therefore, when the canopy 12 of the infant care apparatus 10 is in its closed position as shown in FIG. 1 , the walls 16 can be dropped downwardly or removed altogether so that the attending personnel can have access to an infant resting on the infant platform 14 to perform interventions on that infant.
Further structural components of the infant care apparatus 10 include a vertical frame member 30 (there may, of course, be more than one such vertical frame member) that is affixed to the base member 18 . There may also be a control module (not shown) that can be affixed to the vertical frame member 30 or members and may include displays of various monitor parameters as well as include the various controls for operation of the functions of the infant care apparatus 10 . The control module can be similar to or the same as shown and described in U.S. Pat. No. 5,474,517 of Falk et al.
A radiant heater 34 is located atop of the vertical frame member 30 and is held there in a fixed position with respect to the infant platform 14 so that the radiant heater 34 can always be focused so as to direct the infrared energy toward an infant that is located on the infant platform 14 .
Turning now to the canopy 12 , it can be seen that the canopy 12 is constructed in two sections, that is, there is a first section 36 and a second section 38 . The first section 36 is pivotally affixed with respect to the infant platform 14 at pivot axis 40 that is basically located proximate to or at one end of the canopy 12 . As used herein, the overall canopy 12 can be seen to have an end, which shall be referred to as the canopy north end 42 for convenience and which is located at the end of the infant care apparatus 10 where the vertical frame members 30 are located and from which the radiant heater 34 extends.
There would also normally be located the control module at that end and therefore the working components of the controls, monitors and the structural components that support the radiant heater 34 are located at the platform north end 44 of the infant care apparatus 10 , taking the same convention as the canopy 12 . In practice, the canopy north end 42 and platform north end 44 are also normally the orientation of the head of the infant.
Accordingly, the location of the pivot axis 40 is at or proximate to the canopy north end 42 and the pivot axis 40 is fixed relative to the infant platform 14 and may be fixed by brackets or other structural components that maintain the pivot axis 40 in that fixed location.
Oppositely disposed from the platform north end 44 is the platform south end 46 and a canopy south end 48 and the feet of the infant are generally oriented toward the platform south end 46 and canopy south end 48 .
In the embodiment shown, the overall configuration of the infant platform 14 , as well as the canopy 12 is generally rectangular such that the platform north end 44 and the platform south end 46 are both the shorter of the sides of the rectangle with lateral sides 50 that are the longer of the rectangular sides. The pivot axis 40 is thus, in the embodiment shown, along the shorter of the sides of the rectangular footprint of the infant platform 14 and the canopy 12 .
Obviously, other configurations of infant platform 14 , and mating canopy 12 can be utilized with the present invention including square configurations or even a circular or arcuate footprints, it only being of importance that one end or part of the canopy 12 be pivotally affixed with respect to the infant platform 14 .
In FIG. 1 , therefore, the second section 3 B is movable relative to the first section 36 and can be slid in the direction toward the platform north end 44 . The sliding relationship between the second section 38 and the first section 36 is carried out while the two sections remain joined together and the sliding relationship can be accomplished by conventional overlapping or interlocking lower edges of the second and first sections 38 , 36 .
As can now be understood in FIG. 1 , the canopy 12 can be pivoted about the pivot axis 40 by lifting the canopy south end 48 in order to gain access to the infant or to convert the infant care apparatus 10 from one functioning as an incubator to one functioning as an infant warmer and the radiant heater 34 energized to direct the infrared energy toward the infant platform 14 .
However, due to the dimensions of the infant care apparatus 10 , if the canopy 12 were a one piece or solid construction, the pivoting of the canopy 12 to its open position would cause the canopy 12 to encounter the radiant heater 34 which is an obstruction to the pivoting of the canopy 12 such that the angular pivoting of the canopy 12 is limited by that obstruction. Thus, the pivoting of the canopy 12 about the pivot axis 40 to allow the infant care apparatus 10 to energize the radiant heater 34 to provide warmth to an infant is prevented since the canopy 10 cannot pivot past the radiant heater 34 , thereby preventing a direct pathway for that infrared energy from the radiant heater 34 to the infant resting on the infant platform 14 .
As can be seen, the canopy 12 must pivot to, or preferable past, the radiant heater 34 in order for the radiant energy to emit from the radiant heater 34 to the infant platform 14 without passing through the plastic material of the canopy 12 .
Turning now to FIG. 2 , there is shown a side view of the infant care apparatus 10 where the second section 38 has been slid toward the canopy north end 42 in the direction of the arrow A, thereby shortening the length of the lateral sides of the canopy 12 and forming an opening or open space shown generally at 52 . The rear end 54 of the second section 38 has become nested within the interior of the first section 36 in shortening that length while the interlocking of the lower edges continues to maintain the first and second sections 36 , 38 affixed together in a sliding relationship. In this position of the first and second sections 36 , 38 of FIG. 2 , the canopy 12 is ready to be pivoted to its open position where access to the infant can be attained and/or the radiant heater 34 can be energized to warm the infant.
Turning now to FIG. 3 , there is a side view of the present infant care apparatus 10 where the canopy 12 has been pivoted to its open position. In this Fig., the canopy 12 has been pivoted about the pivot axis 40 in the direction of the arrow B and due to the shortened length brought about by the relative movement of the second section 38 toward the first section 36 , the canopy 12 can be pivoted past the radiant heater 34 and that obstruction is avoided and the canopy 12 can be pivoted to an angular, generally vertical orientation so that the radiation by the radiant heater 34 can be directed toward the infant platform 14 without passing through the canopy 12 .
As shown, the pivotal movement of the canopy 12 can be carried out manually by the user simply lifting the canopy south end 48 , however, in an alternate embodiment, there may be a motor 56 , such as a small DC or stepper motor, to carry out the pivoting motion of the canopy 12 as it moves between its open and its closed positions.
Next, turning to FIG. 4 , there is shown a side view of an alternative embodiment and many of the components are the same as in the FIGS. 1-3 embodiment and have been identified with the same numbers. In this embodiment, the first section 36 of the canopy 12 is, again, pivotally affixed with respect to the infant platform 14 by means of the pivot axis 40 and which is located at or proximate to the canopy north end 42 . As with the prior embodiment, the canopy 12 can be raised for access to the infant or to convert the infant care apparatus 10 to the infant warmer function by simply lifting the canopy south end 48 about the pivot axis 40 .
With this embodiment, however, the second section 38 of the canopy is a trap door 60 that is formed in the canopy 12 and is shown in its closed position in FIG. 4 . The trap door 60 is pivotal affixed to the first section 36 of canopy 12 by means of a hinge 62 forming a pivot axis. The trap door 60 is biased toward its closed position and retained in that closed position by a spring 64 .
Accordingly, turning to FIG. 5 , there is a side view of the infant care apparatus 10 of the FIG. 4 embodiment shown with the canopy 12 in its open position. As is illustrated, the raising or pivoting of the canopy 58 has been moved to the location where it has encountered the obstruction, that is, the radiant heater 34 . As the canopy 12 encounters that obstruction, the trap door 60 is pushed to its open position against the bias of the spring 64 so that the radiant heater 34 can actual enter and pass through the opening or space 66 in the canopy 12 that is created by the opening of the trap door 60 . While only one trap door 60 is illustrated, there may be a plurality of trap doors used consistent with the spirit of the present invention.
Therefore, as with the embodiment of FIGS. 1-3 , the canopy 12 can be opened sufficiently to allow the radiant energy emitted by the radiant heater 34 to be directed to the infant platform 14 and not be impeded by the presence of the canopy 12 .
As with the prior embodiment, while the canopy 12 of this embodiment can be opened and closed manually there may also be a motor 66 that can be energized to move the canopy 12 between the open and closed positions and even the trap door 60 can be opened and closed by means of a motor 68 . As such, therefore, the operation of the canopy 12 and the trap door 60 can be automatically controlled by the user with the trap door 60 normally being opened by means of the motor 68 prior to its encountering the radiant heater 34 .
Those skilled in the art will readily recognize numerous adaptations and modifications which can be made to the infant care apparatus of the present invention which will result in an improved telemetry system for an infant care apparatus, yet all of which will fall within the scope and spirit of the present invention as defined in the following claims. Accordingly, the invention is to be limited only by the following claims and their equivalents.
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An infant warming apparatus for supporting an infant upon an infant platform. A radiant heater is located above the infant platform at one end thereof. A canopy covers the infant platform and is movable between a closed position where the infant is enclosed and an open position providing access to the infant and/or the radiant heater can be energized to direct infrared energy toward the infant platform. The canopy is constructed of two sections, one of which is pivotally affixed with respect to the infant platform at or proximate the one end and the other section is movable relative the one section to create an open space so that when the canopy is pivoted to its open position past the radiant heater, the radiant heater is aligned with respect to the open space to allow the radiant energy to reach the infant platform without passing through the canopy.
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FIELD OF THE INVENTION
The present invention relates to the field of wireless communication and, more particularly, to enhanced communication systems with improved symbol spreading to improve frequency diversity.
BACKGROUND OF THE INVENTION
Wireless personal area networks (WPANs) provide wireless short-range connectivity for electronic devices such as audio/video devices within a home. The Institute of Electrical and Electronics Engineers (IEEE) 802.15 High Rate Alternative PHY Task Group (TG3a) for WPAN is working to develop a higher speed physical (PHY) layer enhancement to IEEE proposed standard P802.15.3™—Draft Standard for Telecommunications and Information Exchange Between Systems (referred to herein as the proposed IEEE standard). Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) has been proposed for the IEEE standard due to its spectrally efficiency, inherent robustness against narrowband interference, and robustness to multi-path fading, which allows a receiver to capture multi-path energy more efficiently.
FIG. 1 illustrates the MB-UWB frequency spectrum. In MB-UWB, the UWB frequency spectrum, which covers 7.5 GHz in the 3.1 GHz to 10.6 GHz frequency band, is divided into 13 bands, which each occupy 528 MHz of bandwidth. Each band includes 128 sub-carriers of 4 MHz bandwidth. Information is transmitted using OFDM modulation on each band. MB-UWB may be coded such that information bits are interleaved across various bands to exploit frequency diversity and provide robustness against multi-path interference. MB-OFDM, however, does not offer sufficient frequency diversity for higher code rates. Typical techniques to increase frequency diversity in MB-OFDM systems often have a relatively high level of complexity, which adds to the cost of implementing such techniques.
SUMMARY OF THE INVENTION
The present invention is embodied in methods, apparatus, and computer program products for transmission of data in multi-band OFDM wideband systems. In accordance with the present invention, a frame of source data is mapped by a transmitter for transmission using a first mapping. The frame of source data is then mapped by the transmitter for retransmission using a second mapping to increase frequency diversity. A receiver may identify source data that experiences fading and communicate the tone/frequency on which the fading occurred to the transmitter so that the transmitter may map the source data that experienced fading during transmission to another tone/frequency for retransmission.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is best understood from the following detailed description when read in connection with the accompanying drawings, with like elements having the same reference numerals. When a plurality of similar elements are present, a single reference numeral may be assigned to the plurality of similar elements with a small letter designation referring to specific elements. When referring to the elements collectively or to a non-specific one or more of the elements, the small letter designation may be dropped. The letter “n” may represent a non-specific number of elements. Included in the drawings are the following figures:
FIG. 1 is a graph of a prior art MB-OFDM frequency spectrum;
FIG. 2 is a timing diagram depicting an acknowledgment and retransmission example for use in describing an aspect of the present invention;
FIG. 3 is a block diagram of an exemplary transmitter in accordance with an aspect of the present invention;
FIG. 4 is a block diagram of an exemplary receiver in accordance with an aspect of the present invention;
FIG. 5 is a block diagram of an alternative exemplary transmitter in accordance with an aspect of the present invention;
FIG. 6 is a block diagram of an alternative exemplary transmitter in accordance with an aspect of the present invention;
FIG. 7 is a block diagram of an alternative exemplary receiver in accordance with an aspect of the present invention;
FIG. 8 is a timing diagram depicting a symbol retransmission scheme in accordance with an aspect of the present invention; and
FIG. 9 is a flow chart of exemplary transmission system steps in accordance with an aspect of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described with reference to the Open Systems Interconnection (OSI) reference model to facilitate description. The OSI reference model sets forth layers present in electronic devices, such as a WPAN compatible electronic devices, to process messages communicated over a network. The OSI reference model includes a physical (PHY) layer, a data-link layer, a network layer, a transport layer, a session layer, a presentation layer, and an application layer. A message originating at a first electronic device for delivery to a second electronic device passes from the application layer of the first electronic device through each layer to the PHY layer, which communicates the message over the network, i.e., a wireless network in a WPAN system. The second electronic device receives the message through its PHY layer and the message is processed through each layer of the second electronic device to retrieve the message from the first electronic device. The data-link layer includes a media access control (MAC) layer and a logical link control layer.
In an exemplary embodiment, the present invention may be implemented as an enhancement to communication systems in accordance with the proposed IEEE standard. The proposed IEEE standard uses a hybrid automatic repeat request (HARQ) scheme to deal with unreliable channel conditions. The HARQ scheme employs a conventional automatic repeat request (ARQ) scheme together with a forward error correction (FEC) technique. If an error is detected, e.g., through a cyclic redundancy check (CRC), the receiving electronic device (herein receiver) requests that the transmitting electronic device (herein transmitter) resend the erroneously received data packets.
Receivers may send acknowledgement messages to transmitters to indicate whether received frames are correctly received and/or demodulated. Acknowledgment type is a function of the MAC layer. There are three acknowledgement types defined for a MB-OFDM MAC layer: no acknowledgment (no-ACK), immediate acknowledgement (Imm-ACK), and delayed acknowledgement (Dly_ACK). The type of acknowledgement is indicated by setting an acknowledgment policy field in a broadcast and multicast addressed frame upon transmission.
A transmitted frame with an acknowledgement policy field set to indicate no acknowledgment (no-ACK) is not acknowledged by the receiver. The transmitter assumes that the transmitted frame is successful for all its local management entities and proceeds to the next frame scheduled for transmission.
A transmitted frame with an acknowledgement policy field set to indicate immediate acknowledgment (Imm-ACK) is acknowledged by the receiver upon receipt. The receiver may acknowledge receipt of the transmitted frame by transmitting an acknowledgment frame back to the transmitter indicating that the transmitted frame was received.
A transmitted frame with an acknowledgement policy field set to indicate delayed acknowledgment (Dly-ACK) is acknowledged by the receiver when requested by the transmitter. The receiver may acknowledge receipt of one or more transmitted frames concurrently by transmitting an acknowledgment frame back to the transmitter indicating that those transmitted frames were received. A delayed acknowledgment schedule (e.g., number of frames between acknowledgments) may be set up during negotiations between the transmitter and receiver. If an acknowledgment frame is not received on schedule, or when requested, the last data frame of the burst may be repeated until an acknowledgement is received. The transmitter may send an empty data frame that was not in the original burst, as an alternative to resending the last data frame, as long as the total number of frames, including the empty one, does not exceed a maximum number of frames. The transmitter may not start or resume burst transmissions until an acknowledgement frame is received. The delayed acknowledgement (Dly-ACK) policy is designed to reduce acknowledgement times for burst transmission.
FIG. 2 is an exemplary timing diagram illustrating implementation of the delayed acknowledgment (Dly-ACK) policy. In FIG. 2 , M stands for MAC Service Data Unit (MSDU) number and F for Fragment (or frame). Mm-Ff represents Fragment f of MSDUm. When an acknowledgment is expected, but not received during a specified time, the transmitter retransmits the frame (or a new frame if the failed frame's retransmission limit has been met) after the end of the specified time. Because the transmitter sending the data frame may not correctly receive an acknowledgement, duplicate frames may be sent even though the intended recipient has already received and acknowledged the frame. Retransmitted frames can be assembled in the same burst with other originally transmitted frames in a known manner.
FIG. 3 depicts a transmitter 300 of a wireless electronic device (herein wireless device), which forms part of a physical layer for the wireless device. The illustrated transmitter 300 includes a scrambler 302 , an FEC encoder 304 , a serial-to-parallel (S/P) converter 306 , an interleaver 308 , a modulator 310 , a pilot/guard/null tone inserter 312 , an inverse fast Fourier transform (IFFT) 314 , a parallel-to-serial (P/S) converter 316 , a frequency hopper 318 , and an antenna 320 . All of these component are controlled by a processor 301 . For the sake of clarity, connections between the processor 301 and the elements of the transmitter 300 are not shown in FIG. 3 . Suitable components for use within the transmitter 300 will be understood by one of skill in the art from the description herein.
The scrambler 102 scrambles the source data. In an exemplary embodiment, the scrambler 102 uses a 15-bit Linear Feedback Shift Register (LFSR) to generate a pseudo random binary sequence (PRBS). The scrambler may be initialized with one of four seeds per frame. The seed identifier may be contained in a physical layer header (PHY header) attached to messages for transmission over the network. The 15-bit seed value chosen corresponds to the seed identifier value, which may be set to 00 when the PHY layer is initialized and incremented using a 2-bit rollover counter for each frame that is sent by the PHY layer, i.e., the seeds may be chosen incrementally and circularly.
The FEC encoder 304 introduces error correction to the source data. The S/P converter 306 coverts the error corrected source data from serial to parallel. Suitable techniques for FEC encoding and S/P conversion will be understood by one of skill in the art from the description herein.
The interleaver 308 rearranges the data to separate consecutive bits of data. In an exemplary embodiment, a different interleaver pattern is used for the transmission of a frame and each subsequent retransmission of that frame. The interleaving pattern is a function of the number of retransmissions and may be predefined.
Table 1 sets forth an example illustrating two interleaving patterns on two different transmissions. Data bits are read in sequential order, i.e., 1, 2, 3, . . . , 198, 199, 200. In a first interleaving pattern (Interleaving I), data bits are read out in the following order: 1, 51, 101, 151, 2, 52, 102, 152, . . . , 49, 99, 149, 199, 50, 100, 150, 200. In a second interleaving pattern (Interleaving II), data bits are read out in the following order: 1, 41, 81, 121, 161, 2, 42, 82, 122, 152, . . . , 39, 79, 119, 159, 199, 40, 80, 120, 160, 200.
TABLE 1
Interleaving Patterns
Interleaving I
Interleaving II
1
51
101
151
1
41
81
121
161
2
52
102
152
2
42
82
122
162
3
53
103
153
3
43
83
123
163
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
48
98
148
198
38
78
118
158
198
49
99
149
199
39
79
119
159
199
50
100
150
200
40
80
120
160
200
The modulator 310 spreads symbols over multiple tones and applies OFDM modulation. In an exemplary embodiment, the modulator 310 is a dual-carrier modulator (DCM) that spreads each symbol over two tones using an operation such as shown in equation 1:
[
y
n
y
n
+
50
]
=
1
10
[
2
1
1
-
2
]
[
x
a
(
n
)
+
j
x
a
(
n
)
+
50
x
a
(
n
)
+
1
+
j
x
a
(
n
)
+
51
]
,
n
=
0
,
1
,
2
,
…
,
49
where
(
1
)
a
(
n
)
=
{
2
n
n
=
0
,
1
,
2
,
…
,
24
2
n
+
50
n
=
25
,
26
,
…
,
49
The block of complex symbols {y n } is then further modulated using an OFDM modulation scheme, such as quadrature amplitude modulation (QAM) or quadrature phase shift keying (QPSK). Where a QPSK modulation is used, a four or five bit analog-to-digital converter (ADC) may offer satisfactory performance due to the simplicity of this modulation scheme. A four or five bit ADC simplifies Fourier transform implementation and facilitates the development of lower power wireless devices. In addition, QPSK modulation enables the description of channel distortion as a phase rotation on each carrier, which can be handled through the use of simple one-tap equalizers.
Table 2 illustrates a dual carrier modulation operation for modulating input bits {x n } to generate output symbols {y n }. In Table 2, four bits are mapped to each symbol and each bit is mapped to two different symbol/tones. For example, bit 1 is modulated onto symbol/tone 1 and 51 along with bits 2, 51, and 52.
TABLE 2
DCM Operation
Output
(symbol)
Input (bits)
1
1
2
51
52
2
3
4
53
54
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
24
47
48
97
98
25
49
50
99
100
26
101
102
151
152
27
103
104
153
154
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
49
147
148
197
198
50
149
150
199
200
51
1
2
51
52
52
3
4
53
54
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
74
47
48
97
98
75
49
50
99
100
76
101
102
151
152
77
103
104
153
154
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
99
147
148
197
198
100
149
150
199
200
In an alternative exemplary embodiment, a multi-carrier technique is utilized where each symbol is multiplied by each element of a vector of length N elements (where N is greater than 2 and each vector element is associated with one tone) to produce N vectors. Thus, each symbol is spread over N tones. The N vectors can be transmitted simultaneously, as they are orthogonal. Thus, the data rate is not changed by the spreading operation.
An advantage of this alternative embodiment is that frequency diversity is achieved up to diversity order N. Spreading a symbol with a spreading code, however, may change the profile of the energy level for the tones. Since UWB systems have a strict emission mask to avoid interference to other existing wireless systems operating in the same spectrum, the signal level of some tones may exceed the emission mask. Reducing the transmission level of these tones reduces/eliminates orthogonolity of the code and decreasing transmission levels of all tones reduces coverage range. A minimum mean squared error (MMSE) equalizer may be used to restore orthogonality.
The pilot/guard/null tone inserter 312 inserts pilot, guard, and null tones into the data. The IFFT 314 transforms the modulated data from the frequency domain to the time domain. The P/S converter 316 converts the data from parallel to serial for transmission. The frequency hopper 318 processes the serial data for transmission from the antenna 320 . The frequency hopper 318 may include a digital-to-analog converter (DAC) for converting digital data to analog for transmission. Alternatively, digital to analog conversion may be performed at other locations within the transmitter 300 . Suitable techniques for pilot/guard/null tone insertion, IFFT transformation, parallel to serial conversion, and frequency hopping for use with the present invention will be understood by one of skill in the art from the description herein.
FIG. 4 depicts a receiver 400 of a wireless device, which forms part of a physical layer for the wireless device. The illustrated receiver 400 includes another antenna 402 , a frequency de-hopper 404 , a S/P converter 406 , a fast Fourier transform (FFT) 408 , a Zero-Forcing Equalizer (ZFEQ) 410 , a pilot/guard/null tone remover 412 , a demodulator 414 , a de-interleaver 416 , a P/S converter 418 , an FEC decoder 420 , and a de-scrambler 422 . All of these component are controlled by a processor 401 . For the sake of clarity, connections between the processor 401 and the elements of the receiver 400 are not shown in FIG. 4 . Suitable components for use within the receiver 400 will be understood by one of skill in the art from the description herein.
The frequency de-hopper 404 follows the frequency hopping used by the transmitter 300 to receive a signal transmitted by the transmitter 300 ( FIG. 3 ) via the antenna 402 . The S/P converter 406 converts the received signal from serial to parallel for processing. The FFT converter 408 converts the signal from the time domain to the frequency domain. The ZFEQ 410 equalizes the signal to minimize any inter symbol interference (ISI) attributable to the modulation performed by the modulator 310 ( FIG. 3 ) in the transmitter 300 . The pilot/guard/null tone remover 412 removes pilot, guard, and null tones. The demodulator 414 reverses the modulation introduced by the modulator 310 ( FIG. 3 ). The de-interleaver 416 reverses the interleaving introduced by the interleaver 308 ( FIG. 3 ). The P/S converter 418 converts the signal from parallel to serial. The FEC decoder 420 decodes the signal. The de-scrambler 422 reverses the scrambling introduced by the scrambler 302 ( FIG. 3 ). The frequency de-hopper 404 may include an analog-to-digital converter (ADC) for converting received analog signals to digital signals. Alternatively, analog to digital conversion may be performed at other locations within the receiver 400 .
FIG. 5 depicts an exemplary transmitter 500 . The transmitter 500 is similar to the transmitter 300 described above with reference to FIG. 3 with the exception that a mapper 502 is inserted between the interleaver 308 and the modulator 310 . When positioned before the modulator 310 , the mapper 502 may remap the input bits being supplied to the modulator 310 . Operation of the mapper 502 is described in detail below. Component common to the two transmitters 300 and 500 are identically numbered and are not described in further detail. The mapper 502 may be integrated with the interleaver 308 with multiple interleavers 308 being employed, i.e., one for each mapping. Each time a frame is transmitted, a different mapping may be used for that frame. Transmitter and receiver mappings for a particular frame may be synchronized through the use of a retransmission number associated with that frame.
FIG. 6 depicts an alternative exemplary transmitter 600 that is similar to the transmitter 500 of FIG. 5 with the exception that the mapper 502 is positioned between the modulator 310 and the pilot/guard/null tone inserter 312 . When positioned after the modulator 310 , the mapper 502 may remap the output symbols generated by the modulator 310 . Those of skill in the art will understand that the mapper 502 may be inserted within the transmitter at other positions from the description herein.
FIG. 7 depicts an exemplary receiver 700 that is configured for use with the exemplary transmitters 500 and 600 of FIGS. 5 and 6 , respectively. The exemplary receiver 700 is similar to the receiver 400 of FIG. 4 with the exception that one or more of the components within the receiver are repeated to handle different mappings introduced by the mapper 502 ( FIG. 5 ). Each group of repeated components is designated with a small letter designation from a-n. The group selected for processing a particular frame may be indicated through the use of a retransmission number associated with that frame.
The mapper 502 ( FIGS. 5 and 6 ) may map a symbol {y n } to {z n } in accordance with equation 2:
z n = { y n transmission y n + iM ( mod ( N ) ) retransmission n = 1 , 2 , … , N ( 2 )
where i is the number of retransmission, M is the offset of a start symbol and N is the total number of symbols in a frame. FIG. 8 illustrates this mapping scheme for a transmission and three retransmissions. FIG. 8 shows that for a total of four transmissions, each symbol {y n } is mapped onto four different tones for transmission. Therefore, without increasing signal processing complexity, a spreading gain of four is achieved.
In the above embodiments, spreading does not take channel characteristics into consideration. Thus, symbols on tones with deep fade may be retransmitted on tones with deep fade again. In an alternative exemplary embodiment, the receiver notifies the transmitter of the best and worst tones. The offset of a next retransmission of the frame is then selected such that the symbols on the worst tone in a previous transmission are mapped to the best tone in a subsequent transmission. In an exemplary embodiment, the receiver records an average level of each symbol. The offset of a next retransmission of the frame is then selected to map the symbols with the lowest reception level onto the best tone in the next retransmission.
The mapping described above is relatively easy to implement and enables easy synchronization between transmitters and receivers. Symbols experiencing the deepest fade, however, may not be mapped to tones with the least fade in the next retransmission. After retransmissions, some symbols may still experience less energy reception than other symbols at the receiver. The energy from multiple transmission of a symbol can be combined to improve the signal to noise ratio of the symbol.
The goal of synchronization in this alternative exemplary embodiment is for receivers to inform transmitters of channel conditions and suggest symbol to sub-carrier mapping for the next retransmission. To simplify synchronization implementation, tones can be divided into a few categories based on the energy level of received signals on the tones. Only those symbols falling into the lowest levels may be specified for remapping to other tones. Other unspecified symbols may be mapped in order, e.g., sequentially, to the remaining tones.
Tone remapping may be achieved by two bit-mapped tables representing current symbol-to-tone mapping and next symbol-to-tone mapping, shown in Table 3. In Table 3, a ‘1’ in the second row represents the tones in the category of lowest signal reception level and a ‘1’ in the third row represents the tones for use in the next transmission of the above symbols. For example, symbols on tones 2, 4, and 5 in the current transmission (shown in the second row) may be retransmitted on tones 3, 6, and 8 (shown in the third row). Other unspecified symbols in the current transmission are arranged in order onto those unspecified tones in the next retransmission, i.e., symbols 1, 3, 6, 7, and 8 may be sent on tones 1, 2, 4, 5, and 7.
TABLE 3 Symbol-to-Tone Mapping Index of tones 1 2 3 4 5 6 7 8 Tone usage of current Tx 0 1 0 1 1 0 0 0 Tone usage of next Tx 0 0 1 0 0 1 0 1
The 128 tones utilize 128 bits, or 16 bytes, for a current symbol-to-tone mapping and 128 bits, or 16 bytes, for a next symbol-to-tone mapping. Thus, 32 total bytes are used. The receiver may send notification of the reception after a burst of frames. This notification may include the mapping bytes.
The various aspects of the present invention provide a mechanism to utilize packet retransmission with symbol spreading to achieve further spreading without increasing implementation complexity. The basic concept is to utilize different mapping of bits to tones in transmissions and subsequent retransmissions so that each bit can be transmitted on different tones in each transmission to increase spreading in frequency. The scheme can be used in multi-carrier wireless communication systems to improve frequency diversity by improving symbol/bit spreading.
FIG. 9 depicts a flow chart 900 of exemplary steps for transmitting a frame of source data over a plurality of tones/frequencies in accordance with an aspect of the present invention. The steps will be described with reference to the transmitters 500 / 600 depicted in FIGS. 5 and 6 and the receiver 700 depicted in FIG. 7 . At block 902 , a scrambler 302 scrambles the source data, a FEC encoder 304 introduces forward error correction to the source data, and an S/P converter 306 converts the source data from serial to parallel.
At block 904 , an interleaver 308 interleaves the bits within the source data. In an exemplary embodiment, the interleaver 308 interleaves the bits within the frame of source data using a first interleave pattern for source data being transmitted for the first time and interleaves the bits within the frame of source data using a second interleave pattern for source data being retransmitted.
At block 906 , a modulator 310 generates symbols from the bits within the frame of source data and modulates each symbol onto at least two of the tones such that each bit is modulated onto at least two different tones. In an exemplary embodiment, the modulator 310 multiples each symbol by each element of a vector having three or more elements, wherein each element is associated with a different tone.
At block 908 , a mapper 502 maps the frame of source data for transmission using a first mapping and maps the frame of source data for retransmission using a second mapping that is different from the first mapping to increase frequency diversity. Subsequent retransmissions of the source data may be mapped using mappings that are different from the first and second mapping (e.g., a second retransmission may be mapped using a third mapping that is different from the first and second mappings) to further increase frequency diversity. The mappings for the retransmitted frames may be based on feedback received from the receiver 700 . For example, the receiver may notify the transmitter 500 / 600 of bits/symbols on tones/frequencies experiencing deep fade in a transmission or retransmission. The processor 301 within the transmitter 500 / 600 may then select a mapping for a first retransmission or subsequent retransmission such that the bits/symbols are mapped to tones/frequencies that are not experiencing deep fade.
In an exemplary embodiment, the mapper 502 is positioned after the modulator 310 such as depicted in FIG. 6 . In accordance with this embodiment, the mapper 502 maps that source data on a symbol-by-symbol basis. In an alternative exemplary embodiment, the mapper 502 is positioned before the modulator 310 such as depicted in FIG. 5 . In accordance with this embodiment, since the bits have not yet been converted to symbols by the modulator 310 , the mapper 502 maps the source data on a bit-by-bit basis. Also, in accordance with this embodiment, the step set forth in block 908 would be performed between the steps set forth in blocks 904 and 906 .
At block 910 , the pilot/guard/null tone inserter 312 inserts pilot, guard, and null tones, the IFFT 314 converts the source data from the frequency domain to the time domain, a P/S converter 316 converts the source data from parallel to serial, and a frequency hopper 318 processes the serial data for transmission. At block 912 , the transmitter 500 / 600 transmits the source data from the antenna 320 .
At block 914 , the receiver 700 receives the transmitted source data at one or more other antennas 402 . At block 916 , the receiver 700 processes the received source data to reverse the modulation, mapping, and interleaving introduced by the transmitter 500 / 600 . In an exemplary embodiment, the receiver 700 includes a frequency de-hopper 404 , a S/P converter 406 , a FFT 408 , a ZFEQ 410 , a pilot/guard/null tone remover 412 , a demodulator 414 , a de-interleaver 416 , and a P/S 418 corresponding to each mapping used by the transmitter 500 / 600 to map the source data.
At block 918 , the processor 401 within the receiver optionally identifies bits/symbols on tones with deep fade and sends at notification to the transmitter (e.g., during acknowledgement) notifying the transmitter of the tones with deep fade so that the transmitter may remap the bits/symbols to tones without deep fade.
At block 920 , the FEC decoder 420 performs error correction and a descrambler 422 descrambles the source data to recover the original source data. In an exemplary embodiment, the source data from multiple transmissions is combined to improve the signal to noise ratio of the transmitted source data. The process is then repeated for one or more retransmissions as indicated by dashed line 950 .
Although the invention has been described in terms of interleavers 308 , de-interleavers 416 , mappers 502 , modulators 310 , and demodulators 414 , the invention may be implemented in software on a computer (not shown). In this embodiment, one or more of the functions of the various components may be implemented in software that controls the computer. This software may be embodied in a computer readable carrier, for example, a magnetic or optical disk, a memory-card or an audio frequency, radio-frequency, or optical carrier wave.
Further, although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.
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Methods and apparatus for use in a multi-band OFDM wideband transmission systems are disclosed. A frame of source data is mapped by a transmitter for transmission using a first mapping. The frame of source data is then mapped by the transmitter for retransmission using a second mapping to increase frequency diversity. A receiver may identify source data that experiences fading and communicate the tone/frequency on which the fading occurred to the transmitter so that the transmitter may map the source data that experienced fading during transmission to another tone/frequency for retransmission.
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BACKGROUND OF THE INVENTION
A common method for cleaning swimming pools involves the use of water jets to stir up sediment on the pool surfaces. The suspended particles are then circulated through a filter for removal. One such cleaning system utilizes a device that is known as a turbo jet. Return water from the filter is ejected by this device as a concentrated, highly directional jet of water that rotates about the dispensing head stirring up sediment from the surrounding pool surface.
While this device has proven effective in serving its intended purpose, it does present a problem of some significance. The problem is that the dispensing head of the turbo jet comprises an obstacle that interferes with other cleaning devices that are frequently employed in the same pool. This problem arises because the dispensing head protrudes perpendicularly from the pool surface. Other cleaning devices that travel over the pool surfaces tend to collide with the projecting dispensing head and then become stalled in position. Hoses, whips and various other cleaning system elements may also be caught or undesirably diverted by the dispensing head.
The present invention provides means for correcting the problem in new dispensing head designs as well as in existing turbo jet equipment.
DESCRIPTION OF THE PRIOR ART
While the turbo jet device is known in the prior art, means for correcting the problems associated with the device are not as yet provided in the prior art.
SUMMARY OF THE INVENTION
In accordance with the invention claimed, means are provided for correcting the problems described earlier wherein the turbo jet dispensing head is found to act as an obstacle that interferes with the proper operation of other cleaning system equipment. For new designs of the dispensing head, the means comprises a modification of the external contours of the dispensing head; for the correction of the problem in existing turbo jet installations the means comprises a cover that is readily installed over the existing turbo jet dispensing head.
It is, therefore, one object of this invention to define a modified external contour for a turbo jet dispensing head which avoids acting as an obstacle that traps other cleaning system equipment or interferes with the effective operation thereof.
Another object of this invention is to provide a cap or cover for existing turbojet dispensing heads as a means for reducing the tendency to trap or interfere with other cleaning system equipment.
A further object of this invention is to provide such a cap or cover in a form that will not interfere with or significantly degrade the performance of the dispensing head itself.
A still further object of the present invention is to provide such a cap or cover in a form which is easily installed and secured in place over the prior art dispensing head in a very short time.
A still further object of this invention is to provide such a cap or cover for a turbo jet dispensing head in a very simple and inexpensive form.
Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more readily described by reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a prior art turbo jet dispensing head installed in a swimming pool;
FIG. 1A is a cross-sectional view of FIG. 1 taken along line 1A--1A of FIG. 1;
FIG. 2 is a perspective view of a modified turbo jet dispensing head in accordance with the improved external contours provided by the present invention;
FIG. 2A is a cross-sectional view of FIG. 2 taken along line 2A--2A of FIG. 2;
FIG. 3 is a perspective view of a cap or cover that may be installed over an existing turbo jet dispensing head and secured in place thereon by means of screws in accordance with the present invention;
FIG. 4 is a perspective view of another embodiment of the present invention in the form of a snap-on cap or cover for a turbo jet dispensing head;
FIG. 5 is a cross-sectional view of FIG. 4 taken along line 5--5 of FIG. 4;
FIG. 6 shows the under side of the cover of FIG. 5 as seen along line 6--6 of FIG. 5;
FIG. 7 is a perspective view of yet another embodiment of the invention in the form of a snap-on ring that may be employed as a cover for a turbo jet dispensing head;
FIG. 8 is a cross-sectional view of FIG. 7 taken along line 8--8 of FIG. 7;
FIG. 9 is a partial bottom view of FIG. 8; and
FIG. 10 is a cross-sectional view taken along line 10--10 of FIG. 9 showing an optional construction for the protective covers of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings by characters of reference, FIGS. 1 and 1A show the prior art dispensing head of a turbo jet swimming pool cleaning device. The turbo jet dispensing head 10 has the form of a thick disc or low cylinder that projects perpendicularly from the surface 11 of the pool bottom or wall.
The dispensing head 10 comprises a finned crown 12, the main portion of which protrudes from the surface 11 of the pool wall, and a valve portion 13 which fits inside an opening in the wall of the pool except for a flange 14 that rests upon the wall surface 11 surrounding the opening.
The molded plastic crown 12 is typically about five and one half inches in diameter and 5/8 inches thick. The combined thickness or height (in the case of a pool floor installation) of the crown and the flange 14 is approximately 3/4 inches--sufficient to comprise an obstacle for other pool cleaning devices, hoses, whips, etc.
The geometry of the crown 12 as shown in FIGS. 1 and 1A comprises a flat circular upper disc 15 (again assuming an upright installation in the pool floor) and integral fins 16 that extend radially outwardly from a centered circular opening 17 to the perimeter 18 of the crown 12. The fins 16, some of which are shown by broken lines in FIG. 1 have wedge shaped outer portions 19. The fins are uniformly spaced about the circumference of the crown 12, serving as the walls of a plurality of channels 21 that extend radially outwardly from the centered circular opening 17 to the circumferential perimeter 18. An observation hole 20 in the center of upper disc or wall 15 is useful as a means for checking the operation of the turbo jet.
The valve portion 13 includes a cylindrical pop-up valve 22 with a slotted longitudinal opening 23 on one side. The valve 22 is controlled by water pressure and a ratcheting mechanism (not shown) that cause the valve 22 to move into the circular opening 17 from which the fins 16 extend. The ratcheting mechanism causes the valve 22 to rotate progressively in steps causing the slotted opening 23 to move from alignment with one channel 21 to alignment with the next, then to the next and so on so that a rotating jet of water 24, 24', 24" etc. is ejected from head 10, sweeping the pool surface 11 surrounding the head and stirring up sediment from the pool surface.
The prior art turbo jet is thus shown to serve its intended purpose with the one drawback, namely its tendency for interference with other cleaning systems. The present invention corrects this deficiency by altering the external contours of the dispensing head 10.
FIGS. 2 and 2A show a modified dispensing head 10' with altered external contours in accordance with the objects of the present invention. Comparing the modified head 10' of FIGS. 2 and 2A with the prior art head 10 of FIGS. 1 and 1A, it is seen that head 10' is the same as head 10 except that the cylindrical edges 26 of head 10 have been replaced by the conical surface 27 of head 10' which serve as a ramp over which an external object such as a hose or whip 28 of another cleaning system may readily ride without becoming trapped or diverted from its intended route of travel.
While the modified contours of head 10' represent a satisfactory solution of the entrapment problem for new-build dispensing heads, there are numerous dispensing heads of the prior art version already installed in swimming pools. For such units, a convenient means for retrofit is needed.
FIG. 3 illustrates a first embodiment of a cap or cover 29 that can be mounted over the top of the prior art dispensing head 10 of FIGS. 1 and 2.
As shown in FIG. 3, the cap 29 fits over the dispensing head 10 like a bottle cap. Arranged about the circumference of the cap 29 are radially oriented, uniformly spaced fingers 31, each aligned with one of the wedge-shaped outer portions 19 of the fins 16 of head 10. The fingers 31 form ramps extending from the pool surface 11 to the top surface 32 of the cap 29 so that, as in the case of the modified head 10' of FIGS. 2 and 2A, other cleaning equipment such as hoses and whips readily move over the head 10 and its cap 29.
The cap 29 has a centered opening 33 aligned with observation hole 20 of head 10 to allow continued visual access to the pop-up valve 22.
The cap 29 is secured to head 10 using an adhesive such as epoxy or by means of screws that pass through screw holes 34 in cap 29 and thread into holes (not shown) that are drilled into the top of head 10 at the time the cap 29 is installed.
The cap or cover 29 can readily be installed over an existing turbo jet dispensing head 10, but the installation can only occur after the pool has been drained (in order to apply the adhesive or to drill the holes and install the screws).
Another embodiment of the invention which can be installed without draining the pool comprises a snap-on cap or cover 35 as shown in FIGS. 4, 5 and 6.
The cover 35 is the same as cover 29 of FIG. 3 except that cover 35 is secured to head 10 by means of two or more snap-action grips 36 uniformly spaced about the circumference of the cover 35 as shown in FIGS. 5 and 6. As shown most clearly in FIG. 5, the grip 36 has a ramped underside that rides over the outer surface of the head 10 as the cover 35 is pressed down over the head 10. The grips then snap into their retaining positions. As shown in FIG. 6, each grip 36 is aligned with a channel 21 of head 10.
Optional design variations applicable to cover 29 as well as to cover 35 are shown in FIG. 5.
To insure that the outer tips of the fingers will bear against the wall of the pool, the resilient fingers may be undercut as indicated by broken line 37. With appropriate dimensioning of the fingers 31, the resilience of the plastic fingers will accommodate thickness tolerances of the head 10 while assuring contact of the finger tips 38 with the pool surface for both covers, 29 and 35, and assuring adequate travel to complete the snapping action of grips 36 in the case of cover 35.
Additionally, the top surface of the cover 29 as well as that of cover 35 may be somewhat rounded or dome-shaped as shown by broken line 39 in FIG. 5.
Yet another embodiment of the invention is shown in FIGS. 7, 8 and 9 in the form of a snap-on ring cover 41. The ring cover 41 has all of the features of the snap-on cover 35 of FIGS. 4, 5 and 6 except that the center of the cover has been cut away to reduce the material content of the protective cover.
An additional variation in the interest of reduced material cost applicable to covers 29, 35 and 41 is shown in FIG. 10. As shown in FIG. 10, the fingers 31 may have a reduced cross-sectional area in a T-shaped configuration with an outer plate or ramp 42 and a longitudinal rib 43 on the underside for strength.
Although but a few embodiments of the invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.
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A cover for the dispensing head of a turbo jet swimming pool cleaning device comprising a plurality of integral radially extending fingers uniformly spaced about the periphery of a circular top, the fingers serving as extensions of vanes incorporated in said dispensing head and also as ramps enabling other swimming pool cleaning equipment to pass without difficulty over the dispensing head.
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Latin name: Malus domestica.
Varietal denomination: ‘CN 121’.
BACKGROUND OF THE NEW VARIETY
The present invention relates to a new, novel, and distinct variety of apple tree, ‘ Malus domestica ,’ and which has been denominated varietally as ‘CN 121’.
ORIGIN
The present variety of apple tree resulted from an ongoing program of fruit breeding which was implemented by the inventor and a licensee. In this regard, seed from an open pollinated ‘Honeycrisp’ apple tree (U.S. Plant Pat. No. 7,197) were collected during the 1994 growing season. These seeds were germinated and the seedlings produced were subsequently grown to a stage of development where they were planted at an orchard which is located at Worthington, Minn. One seedling designated ‘CN 121’ was selected, in 2004, as having desirable characteristics. Subsequently, budwood was removed from this promising seedling and were then budded onto M26 rootstock (unpatented) in 2007. This M26 rootstock was then growing in the orchard of a licensee which is located near Ephrata, Wash. Subsequently, periodic evaluations of the trees and the fruit produced from this first asexually reproduced seedlings were compared to the fruit and other tree characteristics of the chance seedling ‘CN 121’ in 2009 and 2010, respectively. The subsequent evaluations of these first asexually produced trees have demonstrated that those asexually reproduced trees run true to the original chance seedling. All characteristics of the original tree, and its fruit, were established, and appear to be transmitted through the succeeding asexual propagations.
SUMMARY OF THE VARIETY
‘CN 121’ is a new and distinct variety of apple tree which is quite distinguishable from the closest known variety, that being, the ‘Honeycrisp’ apple tree (U.S. Plant Pat. No. 7,197) from which it was derived as a chance seedling. In this regard, the fruit produced by the ‘CN 121’ apple tree develops an intense fruit skin color and pattern, whereas the fruit produced by the ‘Honeycrisp’ apple tree exhibits a striped pattern. In addition to the foregoing, the fruit produced by the new variety of apple tree ripens ten days later than the ‘Honeycrisp’ apple trees when grown at the same geographical location, and under the same cultural conditions. Moreover, internal indices of the new variety show that the fruit produced by this new apple tree has a greater fruit pressure; higher sugar content; higher pH; and lower titratable acid content as compared to the fruit produced by the ‘Honeycrisp’ apple tree (U.S. Plant Pat. No. 7,197).
BRIEF DESCRIPTION OF THE DRAWINGS
This new variety of apple tree is illustrated by the accompanying photographic drawings.
FIG. 1 is a picture of the original dormant ‘CN 121’ mother tree as currently seen in the orchard where it is growing.
FIG. 2 is a picture of a second generation ‘CN 121’ apple tree shown at full bloom.
FIG. 3 shows the fruit produced by a mature, second generation, ‘CN 121’ apple tree.
FIG. 4 depicts the fruit produced by a second generation ‘CN 121’ apple tree as compared to the fruit produced by a ‘Honeycrisp’ apple tree (U.S. Plant Pat. No. 7,197).
The colors in these photographs are as nearly true as is reasonably possible in a color representation of this type. Due to chemical development, processing, and printing, the leaves and fruit depicted in these photographs may, or may not, be accurate when compared to the actual specimen. For this reason, future color references should be made to the color plates (Royal Horticultural Society) and descriptions provided, hereinafter.
NOT A COMMERCIAL WARRANTY
The following detailed description has been prepared to solely comply with the provisions of 35 U.S.C. §112, and does not constitute a commercial warranty (either expressed or implied), that the present variety will, in the future, display the botanical, pomological or other characteristics as set forth, hereinafter. Therefore, this disclosure may not be relied upon to support any future legal claims including, but not limited to, breach of warranty of merchantability, or fitness for any particular purpose, or non-infringement which is directed, in whole or in part to the present variety.
DETAILED DESCRIPTION
Referring more specifically to the pomological details of this new and distinct variety of apple tree, the following has been observed during the sixth fruiting season under the ecological conditions prevailing at the orchards of a licensee which are located near Ephrata, Wash. All major color code designations are by reference to The R.H.S. Colour Chart (Fourth Edition) provided by The Royal Horticultural Society of Great Britain. Common color names are also occasionally used.
TREE
Size .—Generally considered average as compared to other common apple cultivars. The current trees were pruned to a height of about 7.5 feet, and had a crown diameter of about 4.5 feet.
Vigor .—Considered moderate for the species.
Tree form .—Considered upright to upright spreading.
Hardiness .—Considered hardy with respect to U.S.D.A. Zone 6[a].
Productivity .—Considered average for the species.
Trunk .—Size — About 2.6 cm in diameter when measured at a height of about 20 cm above the graft union.
Bark texture .—Rough.
Bark color .—Gray/orange (RHS gray/orange group 165B).
Lenticels .—Generally — Present, and in moderate number. About 18 lenticels will be found in a four square centimeter area.
Lenticels .—Shape — Elongated.
Lenticels .—Width — About 0.3 mm to about 0.5 mm.
Lenticels .—Length — about 1.5 to 2.7 mm.
Lenticels .—Color — Orange/white (RHS 159B).
First year branches.— Diameter — When measured at the mid-point of growth the diameter is about 3.4 mm to about 4.4 mm.
Color .—Gray/orange (RHS Group N199C).
Lenticels .—Numbers — Considered numerous.
Lenticels .—Shape — Round, and about 0.2 mm in diameter.
Lenticels .—Color — White (RHS 155D).
Branch pubescence .—Generally — Considered present, and light in abundance.
Branch pubescence .—Color — Gray/orange (RHS Group 166A).
Internodes .—Size — About 3.1 cm to about 4.1 cm in width.
Dormant fruiting buds .—Shape — Considered conical.
Dormant fruiting buds .—Length — About 7.4 mm.
Dormant fruiting buds .—Basal Diameter — About 3.5 mm.
Dormant fruiting buds .—Color — Gray/orange (RHS 199C).
Two year old fruiting branches .—Size — Generally — About 5.8 mm to about 9.0 mm in diameter when measured at approximately the mid-point of the growth. Branch Color — Gray/brown (RHS Group 199A). Spur Development — Generally — Considered light. Spur Length — About 1 cm to about 2.9 cm in length. Spur Shape — Considered moderately acute.
Lenticels .—Numbers — Numerous, and averaging about 15 lenticels per square centimeter of surface area.
Lenticels .—Shape — Considered generally oval.
Lenticels .—Length — About 0.9 mm.
Lenticels .—Width — About 0.4 mm.
Lenticels .—Color — White (RHS Group 155D).
Scaffold branches .—Size — About 1 cm to about 1.3 cm in diameter when measured at a distance of about 10 cm from the trunk.
Scaffold branches .—Crotch Angle — As currently trained in the orchard, the crotch angle is about 45 degrees from the vertical. However, this characteristic should not be considered distinctive of the present variety.
Scaffold branches .—Color — Gray/brown (RHS N199C).
Scaffold branches .—Lenticels — Numerous lenticels are present. On average, about 8 lenticels appear per square centimeter of surface area.
Scaffold branch lenticels .—Shape — Elongated and small.
Scaffold branch lenticels .—Size — About 0.7 mm in width and in length.
Scaffold branch lenticels .—Color — Orange/white (RHS Group 159C).
LEAVES
Leaf shape .—Generally — Considered broadly acute and generally upwardly folded.
Leaf texture .—Dorsal Surface — Considered leathery and slightly undulating.
Leaf texture .—Lower Surface — Considered glabrous.
Surface sheen .—The dorsal surface has a high sheen. The ventral surface has a somewhat dull appearance.
Pubescence .—Generally — The pubescence appears on the ventral surface only, and covers substantially the entire surface.
Pubescence .—Texture — Considered fine.
Pubescence .—Color — White (RHS 155C).
Leaves .—Length — Variable from about 77 mm to about 100 mm.
Leaves .—Width — About 48 mm to about 62.8 mm.
Leaves .—Marginal Form — Considered mostly serrate, although occasionally bi-serrate portions will be seen.
Leaf tip shape .—Generally — Considered acuminate.
Leaves .—Base Shape — Considered rounded.
Leaves .—Stipules — Generally absent. On occasion one will be found on a petiole. Stipules — Length — About 7.1 mm. Stipules — Width — About 1.1 mm. Stipules — Color — The dorsal and ventral surfaces both have a yellow-green color (RHS 147B).
Leaf pubescence.— Generally — The Pubescence is generally present on the ventral surfaces, but it is considered fine in texture. The leaf pubescence only covers about 50% of the ventral leaf surface.
Leaf pubescence.— Color — White (RHS 155C).
Leaf blade color.— Dorsal Surface — Yellow/green (RHS 147A).
Leaf blade color.— Ventral Surface — Yellow/green (RHS 147C).
Leaf midvein.— Shape — Considered prominent, and having a fine pubescence on its ventral surface.
Leaf mid-vein.— Width — When measured at midblade it is about 1.1 mm in width.
Mid-vein color.— Dorsal Surface — Gray/yellow (RHS 160C).
Mid-vein pubescence.— Color — White (RHS 155C).
Petiole.— Length — About 20.2 to 35.4 mm.
Petiole.— Diameter. When measured at the mid-point, it is about 1.3 to 1.7 mm.
Petiole.— Color — Yellow/Green (RHS 147D). Further highlights of gray/red (RHS 181A) are seen at the basal end thereof.
Petiole.— Pubescence — Generally it is considered abundant, and having a fine texture over the entire length and circumference of the petiole.
Pubescence color.— White (RHS 155C).
FLOWERS
Date of full bloom.— In 2010, the date of full bloom was April 27.
Number of blossoms per bud.— Generally 5 to 6 blossoms will be found per bud.
Flower size.— Generally — Considered medium to medium large.
Flower diameter.— At full expansion it is about 43 to about 51 mm.
Flower petals.— Width — About 20 to about 23 mm.
Flower petals.— Length — About 14 to about 19 mm.
Flower petals.— Color — White (RHS 155B). Further, the flower petals may have highlights of gray/purple (RHS 186D).
Petal vein color.— Gray/purple (RHS 186B).
Flower stamen.— Numbers — About 18 to 20 stamens will be found.
Filament.— Length — About 5.2 to 11.8 mm.
Filament color.— Yellow (RHS Group 2D).
Anthers.— Shape — Kidney shaped.
Anthers.— Width — About 1.6 mm.
Anthers.— Length — About 1.7 mm.
Anthers.— Color — At full maturity the anthers gray/yellow (RHS 160C).
Pistil.— Length — About 14.3 to about 16.1 mm.
Styles.— Numbers — Typically 5, and they are usually fused at the middle.
Styles.— Color — They are usually white, and pubescent below the union.
Styles.— Length — About 6.9 to about 8.7 mm.
Styles.— Color — Yellow/green (RHS 144C).
Stigma.— Shape — Club-like.
Stigma.— Color — Gray/yellow (RHS 162A).
Sepals.— Numbers — Typically 5 per blossom are found.
Sepals.— Form — Usually the sepals are curled back towards the peduncle.
Sepals.— Shape — Considered deltoid.
Sepal tip.— Shape — Acuminate.
Sepal base.— Shape — Truncate.
Sepals.— Length — About 8.4 mm.
Sepals.— Width — About 3.8 mm.
Sepal pubescence.— Generally speaking this is present on both the dorsal and ventral surfaces.
Sepal color.— Green (RHS 146C). Further the tips of the sepals are typically highlighted with a gray/orange color (RHS 165A).
Peduncle.— Length — About 16 to about 20 mm.
Peduncle.— Color — Yellow/green (RHS 144A). Occasionally a yellow/green color (RHS 152A) appears along the mid-ribs of the peduncle.
FRUIT
Maturity when described.— Ripe for harvesting and shipment about Sep. 19, 2010. This harvesting date was 10 days later than the apple tree ‘Honeycrisp’ which was growing at the same geographical location and under similar cultural conditions.
Fruit form.— Considered mostly conical, and occasionally round, with about 50% of the fruit appearing lopsided. The equatorial cross-sectional shape is irregular.
Fruit size.— Considered medium to medium large under normal crop loads.
Equatorial fruit diameter.— About 83.6 mm.
Axial diameter.— About 74.5 mm.
Fruit stem.— Length — Considered medium, about 22.1 mm.
Fruit stem.— Diameter — About 2.4 mm.
Stem cavity.— Average Width — About 34.3 mm.
Stem cavity.— Average Depth — About 19.3 mm.
Stem cavity.— Shape — Acute.
Stem cavity.— Form — No lipping is apparent.
Basin cavity.— Average width — About 28.7 mm.
Basin cavity.— Average depth — About 10.3 mm.
Basin cavity sides.— Shape — Rounded.
Eye.— Generally considered erect.
Sepal.— Color — White (RHS 155C) and appearing downy in appearance.
Fruit skin.— Surface — Considered glabrous and a light bloom is present.
Fruit skin.— Appearance — Considered washed out, especially on the side of the fruit which is not directly exposed to sunlight.
Fruit color.— Generally — The overall color is more intense on exposed sides.
Skin color.— Overcolor — Red (RHS 46A).
Skin color.— Undercolor — Yellow/green (RHS 150C).
Fruit skin thickness.— Generally — Medium.
Fruit skin texture.— Considered tough.
Fruit skin lenticels.— Generally — Scattered, small, and considered indistinct and more numerous towards the Calyx end of the fruit.
Lenticels.— Numbers — About 3 per cm square are found when measured at the stem end, and 10 per cm square when this is measured at the Calyx end.
Lenticels.— Surface Texture — Smooth. The skin appears areolar in appearance.
Lenticels.— Surface Color — White (RHS N155D).
Lenticels.— Size — About 0.2 to about 0.4 mm in diameter but otherwise considered round.
Fruit core.— Position — Considered distant.
Fruit core.— Line position — Basal clasping.
Fruit core.— Diameter — About 32.7 mm.
Fruit core.— Length — About 26.9 mm.
Fruit core.— Shape — Considered flat and conical.
Fruit cell.— Numbers — 5.
Fruit cell.— Form — Considered tufted, and narrow lines circumvent the cell walls.
Tuft.— Color — The tufting is white (RHS 155C).
Fruit cell.— Shape — Considered elliptical.
Fruit cell.— Length — About 17.1 mm.; Fruit Cell — Width — about 9.3 mm.
Fruit cell.— Depth — About 7 mm.
Tube.— Shape — Cone-like.
Stamen position.— Generally considered medium.
Axis.— The cells are axially disposed and considered open.
Seeds.— Numbers — 1-2 seeds are found, mostly 2.
Seed shape.— Generally — Considered mostly acute, and some approaching acuminate in shape.
Seed length.— About 8.3 to 8.9 mm.
Seed width.— About 4 mm to about 5.3 mm.
Seed color.— Brown (RHS Group 200B).
Fruit flesh.— Generally — Considered firm, crisp, melting, sweet, sub-acid and juicy.
Flesh texture.— Considered medium coarse grained.
Flesh color.— White (RHS 155A).
Flesh aroma.— Apple-like, and mild in intensity.
Fruit pressure.— The new variety of apple tree produces fruit having a fruit pressure of about 17.5 pounds. This is higher than the fruit pressure produced by the fruit of the ‘Honeycrisp’ apple tree. When that tree is grown under the same ecological conditions its fruit has a pressure of about 13.76 pounds.
Brix.— The new variety of apple tree, at commercial maturity, produces fruit having a brix of about 14.6. This brix is higher than that produced by the fruit of the ‘Honeycrisp’ apple tree (U.S. Plant Pat. No. 7,197) which, when grown under the same ecological conditions, has a brix of about 13.8.
pH.— At commercial maturity, the fruit of the present variety of apple tree has a pH of about 3.43. This pH is lower than that produced by the fruit of the ‘Honeycrisp’ apple tree (U.S. Plant Pat. No. 7,197) which, at full commercial maturity, and grown under the same ecological conditions, has a pH of about 3.35.
Fruit keeping quality.— Considered excellent. The fruit of the present variety has been kept up to five months in cold storage with no deleterious effects noted.
Pollination.— The present variety may be pollinated by any diploid apple tree that blooms at approximately the same season.
Fruit use.— Considered a fresh desert apple.
Disease and insects resistance.— The present variety is considered to be susceptible to all insects and diseases found in the region of central Washington.
Although the new variety of apple tree which is described herein possesses the aforementioned characteristics when grown under the ecological conditions prevailing near Ephrata, Wash., in the central part of Washington State, it should be understood that variations of the usual magnitude and characteristics incident to changes in growing conditions, fertilization, pruning, pest control, frost and climatic variables and other horticultural management practices are to be expected.
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A new and distinct variety of apple tree ‘ Malus domestica ’ which is denominated varietally as ‘CN 121’ and which produces an attractively colored apple which his mature for harvesting and shipment approximately September 19 under the ecological conditions prevailing near Ephrata, Wash., in the central portion of Washington State.
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FIELD OF THE INVENTION
[0001] The present invention relates to data input devices for electronic devices and, more particularly, to multiple key assemblies for electronic devices.
BACKGROUND OF THE INVENTION
[0002] Nowadays, there is a considerable consumer demand for electronic devices having a small form factor, and there is also a competing consumer demand for such electronic devices that include more and more features. This competing demand generally translates into greater data processing and display capabilities, which typically requires greater real estate in the electronic device. With regard to display capabilities, it is considered desirable to provide an electronic device with as large a display screen as practical. However, increasing the size or viewable area of a display screen associated with a small form factor electronic device leaves little room for data entry from a conventional keypad matrix, such as a keypad matrix shown in U.S. Pat. No. D 416,024. It is not practical to continue reducing the size and/or the spacing of the buttons that form a conventional keypad matrix arrangement.
[0003] To overcome the foregoing difficulties, U.S. Pat. No. 6,157,323 discloses a multiple key assembly to integrate a plurality of key segments together, resulting in a keypad matrix occupying less room. A similar multiple key assembly is also described in U.S. Pat. No. 6,441,753. Both the multiple key assemblies can rotate around a pivot so that a user can select and depress a specific key segment to electrically connect with a printed circuit board (PCB) while the other key segments remain disconnected. However, because the key segments of the above multiple assemblies are integral, when a key segment is depressed, the other key segments maybe also be depressed or influenced and thus an incorrect manipulation frequently occurs. In addition, the sense of depressing the key segment is not satisfactory due to the bad elasticity of the multiple key assemblies.
[0004] Therefore, an improved multiple key assembly of an electronic device is desired to overcome the disadvantages of the prior art.
SUMMARY OF THE INVENTION
[0005] A main object of the present invention is to provide a multiple key assembly for an electronic device which can avoid incorrect manipulation thereof.
[0006] Another object of the present invention is to provide a multiple key assembly for an electronic device which provides a good sense of manipulation.
[0007] To achieve the above objects, a multiple key assembly of an electronic device comprises a central key, four key segments for surrounding the central key, a base member and a printed circuit board. The central key and the four key segments are separated from each other. The base member has an outer portion called a base, a central portion called a circular platform, and a plurality of connecting parts flexibly connecting the circular platform with the base. A plurality of contacts is provided on bottoms of the circular platform and the connecting parts. The printed circuit board provides a plurality of contact pads corresponding in position to the contacts on the base member. During assembly, the central key and the four key segments are first mounted on the base member and then the base member with the keys is secured to the printed circuit board with the plurality of contacts of the base member suspended above the corresponding contact pads on the printed circuit board. When manipulating the keys, one of the keys is pressed to make the circular platform or the corresponding connecting part move downwardly until the contact corresponding in position to the key contacts with the corresponding contact pad on the printed circuit board and a circuit is closed. When the key is released, the depressed key will recover to its original position under the elastic force exerted by the circular platform of the base member. If desired, an elastic spacer can be mounted on the base member to increase the elastic force exerted against the four key segments. Of course, a key sheath also can be included to cover the multiple key assembly.
[0008] Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of a preferred embodiment thereof when taken in conjunction with the accompanying drawings, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is an exploded, perspective view of a multiple key assembly of an electronic device in accordance with a first embodiment of the present invention viewed from a top aspect;
[0010] [0010]FIG. 2 is an exploded, perspective view of the multiple key assembly of FIG. 1, viewed from a bottom aspect;
[0011] [0011]FIG. 3 is a perspective view of the assembled multiple key assembly of FIG. 1 viewed from a top aspect;
[0012] [0012]FIG. 4 is a perspective view of the assembled multiple key assembly of FIG. 3 viewed from a top aspect; and
[0013] [0013]FIG. 5 is an exploded, perspective view of a multiple key assembly of an electronic device in accordance with a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] With reference now to the drawings in detail, FIGS. 1 and 2 show a multiple key assembly 100 for an electronic device in accordance with a first embodiment of the present invention. The multiple key assembly 100 comprises a central key 1 , a plurality of key segments 2 , an elastic spacer 3 , a base member 4 , a key sheath 5 , a printed circuit board (PCB) 6 and a plurality of bolts 7 .
[0015] The central key 1 has the shape of a flat cylinder and define a blind hole 12 in its bottom. The key segments 2 are separated from each other and constitute a ring-shaped configuration. Each key segment 2 is substantially a hollow cover with a cavity defined in its bottom; said cavity is divided into two engaging holes 24 by a central wall 22 thereof. Two gaps 26 are formed in the bottom of each key segment 2 adjacent to two ends thereof and respectively communicate with the two engaging holes 24 . The central key 1 and the key segments 2 constitute a multiple key (not labeled). The elastic spacer 3 has a ring 32 and a plurality of pairs of elastic legs 34 extending therefrom. Each pair of elastic legs 34 comprises a first leg 36 and a second leg 38 , which are positioned and shaped to engage with the gaps 26 of a single key segment 2 .
[0016] The base member 4 has an outer portion, called a base 42 , a central portion, called a circular platform 44 , which is formed in a middle of the base 42 and a plurality of connecting parts 46 connecting the base 42 with the circular platform 44 . A protrusion 442 extends upwardly from the circular platform 44 . A bottom surface (not labeled) of the circular platform 44 is coplanar with bottom surfaces (not labeled) of the connecting parts 46 and is spaced above a bottom surface (not labeled) of the base 42 , thus a shallow concavity 41 is formed beneath the circular platform 44 and the connecting parts 46 . Also, a plurality of spaces 48 is defined between the connecting parts 46 . Each connecting part 46 has a stepped configuration and forms three steps having different heights, i.e., a lowest seat 466 , an interior step 468 , and a highest step 467 between the seat 466 and the interior step 468 . A slot 462 is formed in a middle of the step 467 of the connecting part 46 to divide the step 467 into two engaging tabs 464 . A plurality of contacts 49 respectively extends from the bottom surfaces of the circular platform 44 and the connecting parts 46 . In the present invention, said contacts 49 are preferably positioned at a middle of said bottom surfaces. A plurality of tab holes 426 and pin holes 424 are provided in the base 42 .
[0017] The key sheath 5 has a round opening 52 to receive the central key 1 and the key segments 2 therein. A plurality of pins 58 and locating tabs 562 extend from a bottom surface of the key sheath 5 . Said locating tabs 562 each having a receiving hole 56 in a middle thereof and a height thereof is substantially identical with a thickness of the base 42 . On a top surface of the key sheath 5 corresponding in position to the receiving holes 56 there are a plurality of glue-receiving openings 59 which communicate with the receiving holes 56 , respectively. The PCB 6 also has a plurality of bolt holes 64 and pin holes 66 defined therein. A plurality of contact pads 62 is provided on the PCB 6 corresponding in position to the contacts 49 of the base member 4 .
[0018] During assembly, first, the elastic spacer 3 is placed on the base member 4 so that the ring 32 is positioned on the seats 466 of the connecting parts 46 and the plurality of pairs of elastic legs 34 are respectively received in the corresponding gaps 26 . A top surface of the ring 32 on the seats 466 now is coplanar with a top surface of the interior steps 468 , thus ensuring the key segments 2 can be stably mounted thereon. Then, the key segments 2 are respectively assembled on the corresponding connecting parts 46 of the base member 4 . Accordingly, the engaging tabs 464 are received in the corresponding engaging holes 24 and the central walls 22 are inserted into the corresponding slots 462 . Also, each pair of the elastic legs 34 are engaged with the two gaps 26 of the corresponding key segment 2 . In a third step, the central key 1 is assembled on the circular platform 44 with the protrusion 442 engaging with the blind hole 12 and all the key segments 2 being arranged around the central key 1 . Thus, assembly of a multiple key subassembly 200 is finished.
[0019] To assemble the multiple key subassembly 200 to an electronic device, the locating tabs 562 and the pins 58 of the key sheath 5 are passed through the corresponding tab holes 426 and pin holes 424 of the base member 4 , while the central key 1 and the key segments 2 extend through the round opening 52 of the key sheath 5 . Bottom surfaces of the locating tabs 562 are then abutted against a top surface of the PCB 6 at positions corresponding bolt holes 64 of the PCB 6 , and the exposed portions of the pins 58 threaded through the pin holes 424 are further extended through the pin holes 66 of the PCB 6 , while the axes of the corresponding receiving holes 56 , tab holes 426 and bolt holes 64 coincide with each other. At this point, the contacts 49 of the base member 4 are suspended above the corresponding contact pads 62 of the PCB 6 . Then the plurality of bolts 7 is extended through the corresponding bolt holes 64 and into the corresponding receiving holes 56 . The bolts 7 are fixedly engaged in the receiving holes 56 by a glue dripping through the glue-receiving openings 59 of the key sheath 5 into the receiving holes 56 . Thus a whole assembly of the multiple key assembly 100 is attained, as shown in FIGS. 3 and 4. It is easily understood that the pins 58 can also be fixed in the pin holes 424 and 66 by glue. Further, the central key 1 and the key segments 2 can be fixed to the base member 4 using the glue.
[0020] When manipulating the multiple key of the multiple key assembly 100 , a key segment 2 or a central key 1 is pressed downwardly. If a key segment 2 is pressed, the corresponding elastic legs 34 and the corresponding connecting part 46 downwardly move until the contact 49 on the connecting part 46 contacts with the corresponding contact pad 62 and a circuit is closed. When the key segment 2 is released, it recovers to its original position under the elastic force exerted by the base member 4 and the elastic spacer 3 . If a central key 1 is pressed downwardly, the circular platform 44 downwardly moves until the contact 49 on the underside of the circular platform 44 contacts the corresponding contact pad 62 on the PCB 6 and the circuit is closed. When the central key 1 is released, it recovers to its original position under the elastic force exerted by the base member 4 .
[0021] According to another embodiment of the present invention, the elastic spacer member 3 can be omitted from the multiple key assembly 100 to form a multiple key assembly 101 , as shown in FIG. 5. In this embodiment, the base member 4 ′ is modified to make the seats 466 ′ of the connecting parts 46 ′ coplanar with the interior steps 48 so as to stably mount the key segments 2 directly thereon without the help of the ring 32 of the elastic spacer 3 . Obviously, the multiple key subassembly 200 can be directly assembled on the PCB 6 by other convention connection methods, and thus the key sheath 5 can also be omitted.
[0022] The central key 1 and the key segments 2 are separated from each other, so it is easy to distinguish them from each other when manipulating the multiple key assembly 100 or 101 , and to thus avoid wrongly depressing the key segments 2 or the central key 1 . In addition, because there is an enough space 48 between every two key segments 2 so that a depressed key segment 2 will not overly influence the adjacent key segments 2 , unwanted electrical connections between other key segments 2 and the PCB 6 are avoided. Furthermore, because of the elastic connection between the circular platform 44 and the base 42 through the plurality of connecting parts 46 , the sense of manipulating the multiple key assembly 100 or 101 becomes more comfortable and a depressed key segment 2 or depressed central key 1 recovers more quickly. Of course, using the elastic spacer 3 can strengthen the above effects.
[0023] It will be apparent that many changes and modifications of the several features described herein may be made with departing from the spirit and scope of the invention. It is therefore apparent that the foregoing description is by way of illustration of the invention rather than limitation of the invention.
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A multiple key assembly ( 100 ) includes a multiple key including a central key ( 1 ) and four key segments ( 2 ) separated from each other, a base member ( 4 ) having a base ( 42 ), a circular platform ( 44 ), a plurality of connecting parts ( 46 ) flexibly connecting the circular platform with the base and a PCB ( 6 ). A plurality of contacts ( 49 ) is provided on bottoms of the circular platform and the connecting parts, and the PCB provides a plurality of contact pads ( 62 ) corresponding in position to the contacts on the base member. During assembly, the multiple key is first mounted on the base member and then both are secured to the PCB with the plurality of contacts of the base member suspended above the corresponding contact pads on the printed circuit board. If desired, an elastic spacer ( 3 ) and/or a key sheath ( 5 ) can be included.
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TECHNICAL FIELD
This invention pertains to the preparation of mixed nitroaromatic compositions, particularly mixed nitration products of benzene and toluene or xylene.
BACKGROUND OF THE INVENTION
Nitroaromatic compositions have been widely used as intermediates in the chemical industry and are suited for producing a variety of industrial chemicals. Typically the nitroaromatic compositions are hydrogenated to form the aromatic amine which then can be used in preparing dyestuffs, or as an intermediate in the urethane industry. Examples of widely used nitroaromatics which are subsequently hydrogenated to the amine include nitrobenzene, dinitrotoluene, and dinitroxylene. These compositions when hydrogenated form aniline, toluenediamine, and xylenediamine, respectively. The former has wide utility for the dyestuff industry while the latter diamines are used as intermediates in the production of diisocyanates for urethane manufacture.
Numerous processes have been developed for effecting nitration of aromatic hydrocarbons; some have focused on the synthesis of mononitroaromatics while others are focused on the production of dinitro or trinitro aromatic compositions. Nitration of aromatic compositions have typically been done by the mixed acid technique, i.e. a mixture of nitric acid and sulfuric acid, although nitration of aromatics has also been affected utilizing nitric acid alone or mixtures of nitrogen oxides and sulfuric acid. Representative patents illustrating some of the nitration techniques are as follows:
U.S. Pat. Nos. 2,362,743, 2,739,174 and 3,780,116 disclose processes for the nitration of aromatic hydrocarbons using nitric acid as the sole nitrating medium. The '743 patent uses a two-stage nitration process to form dinitrotoluene in the first stage, toluene is nitrated with 60-75% nitric acid at temperatures about 75°-80° C. and then dinitrated with 90-100% nitric acid at the same temperature. In the '174 patent benzene, toluene, and xylene were nitrated using 70% nitric acid at temperatures of from about 110°-120° C. In the process, a liquid reaction mixture comprising water, nitric acid and nitrated hydrocarbon was withdrawn from the reactor and the nitric acid separated from the water nitrated hydrocarbon azeotrope via distillation. The '116 patent used approximately 40% nitric acid as the nitrating medium for benzene and toluene and the process involved bubbling hydrocarbon vapor through the nitric acid medium at temperatures of from about 50°-100° C. A nitrobenzene-nitric acid mixture is withdrawn from the reactor and the mixture separated by decavitation. Nitric acid and unreacted benzene and water are removed as vapor with the benzene being separated and returned.
By and large the technique for nitrating aromatic hydrocarbons such as benzene, toluene, zylene, napthalene, anthraquinone has been the mixed acid technique. U.S. Pat. Nos. 2,256,999; 2,370,558; 2,773,911; 2,849,497; 3,434,802; 4,021,498; and 4,112,005 disclose variations in the mixed acid technique for producing nitroaromatic compositions and particularly, mono and dinitroaromatic compositions. The mixed acid technique is preferred in the manufacture of nitroaromatics since the concentration of the nitronium ion, which is the nitrating agent, is much lower in nitric acid alone than in the mixed acid. In the mononitration of aromatics, the aromatic hydrocarbons are contacted with a nitric acid/sulfuric acid mixture, the nitric acid concentration typically being about 20-70% by volume or more dilute than in dinitration reaction. The sulfuric acid typically used in 80-98% concentration.
The '005 patent mentioned above discloses preparing the mononitroaromatic compounds by nitrating a reactive aromatic compound in the absence of sulfuric acid until mononitration is complete, the nitration being carried out at 40-68% by weight nitric acid.
Dinitroaromatics, e.g. dinitroxylene and particularly dinitrotoluene have been typically produced by using highly concentrated nitric acid compositions or the mixed acid technique and U.S. Pat. Nos. 2,362,743; 2,934,571; and 3,092,671 are representative. The '743 patent effects dinitration of toluene in the absence of sulfuric acid. The mononitration is carried out with 70% nitric acid, while the dinitration is carried out using 98% nitric acid at temperatures of about 70°-80° C. High mole ratios of acid. e.g. 2-5:1 moles nitric acid per mole hydrocarbon, are required. The '571 patent discloses the nitration of various aromatics such as benzene. nitrobenzene, halogen-substituted benzenes, and so forth by the mixed acid technique. In that process a mixture of fuming nitric acid and fuming sulfuric acid are reacted with the aromatic hydrocarbon at temperatures of 50°-60° C.
Commercially, the nitration of toluene to form dinitrotoluene is done in a two-step process Wherein mononitrotoluene is formed in a first stage, the water of reaction and spent acid being removed from the mononitrobenzene reaction product and then the mononitrobenzene charged to the dinitrator for subsequent nitration.
The hydrogenation of nitroaromatics to the amine, e.g. nitrobenzene to aniline and dinitrotoluene to toluenediamine, usually has been carried out by effecting the hydrogenation in aqueous phase over a hydrogenation/dehydrogenation catalyst such as Raney nickel. Normally in the hydrogenation process, the nitrated product is purified and removed of acidic material and alkaline material which act as catalyst poisons in the hydrogenation reaction. U.S. Pat. No. 4,224,249 discloses such a process for this hydrogenation.
Recently it has been reported (U.S. Pat. No. 4,185,036) that mixed nitroaromatic compositions can be hydrogenated under appropriate conditions to form aromatic amines with less by-product tars at higher rates and higher yields than are achieved with prior art hydrogenation processes. More particularly, the patent discloses that a mixture of aromatic compounds can be selectively hydrogenated to the amine, the mixture containing at least 25% of a mononitronon-aminoaromatic compound and at least 25% of a dinitro or a mononitro-amino compound. Examples of reactants which are suited for the selective cohydrogenation include o-nitrotoluene, o-nitroaniline, mononitrotoluene, dinitrobenzene, dinitrotoluene and other nitro aromatics.
In view of the ability to selectively hydrogenate mixed aromatic compounds while reducing the amount of tar formation during the hydrogenation of such compounds, a need was created for feeds of mixed nitroaromatic compositions. The need was originally satisfied by mixing a purified mononitronon-amino compound with a purified dinitro compound or a nitroamino aromatic and the hydrogenation effected of that mixture. Although this process is well-suited to the creation of mixed nitroaromatic compounds, there were problems associated in the preparation of the purified nitroaromatics due to the reaction conditions and separation techniques.
SUMMARY OF THE INVENTION
This invention pertains to the manufacture of a mixture comprising a mononitro aromatic compound and a dinitro aromatic compound, optionally including other nitro aromatics, which can be selectively cohydrogenated to form the corresponding aromatic amine. In a preferred embodiment, the nitro aromatic composition comprises a mixture of mononitrobenzene and dinitrotoluene. The process involves the reaction of a feed mixture comprising benzene and toluene with nitric acid under conditions suited for nitration. Typically, the nitric acid concentration is from 88 to 95% by weight at the steady state and the reaction temperature is from 40° to 70° C. The reaction time is sufficient to effect mononitration of the benzene but insufficient for effecting substantial dinitration of the benzene in the feed mixture.
Many advantages are associated with the process of this invention, and these advantages include:
the ability to utilize refinery streams comprising benzene and toluene, optionally with small amounts of xylene, without prior separation to form a suitable feedstock for nitration:
an ability to selectively nitrate a feed mixture to form a nitroaromatic mixture consisting primarily of mononitrobenzene and dinitrotoluene as the nitrated benzene and toluene products;
an ability to selectively form mononitrobenzene and dinitrotoluene in combination with each other for further hydrogenation without a plurality of separation stages involving the separation of unstable nitroaromatic compositions; and
an ability to reduce the amount of process steps necessary to produce aromatic amine intermediates without numerous separation stages prior to the generation of such aromatic amine intermediates.
DETAILED DESCRIPTION OF THE INVENTION
This invention is particularly adapted to the nitration of hydrocarbon feedstocks consisting primarily of benzene and toluene with optional amounts of other aromatic hydrocarbons, e.g. xylene. Typically, these feedstocks comprise from about 20 to 80 wt % benzene, 20 to 80% toluene and the balance consisting of xylene or other hydrocarbons such as napthalene or non-nitratable hydrocarbon. Although the nitration of a feed mixture of benzene and toluene can be broadly reacted where the benzene is present in a proportion of from 5 to 95% by weight, preferred reaction systems comprise from about 20 to 80% benzene and 20 to 80% toluene so that desired levels of both mononitrobenzene and dinitrotoluene can be produced for cohydrogenation.
Nitration of the aromatic hydrocarbon stream is effected by utilizing essentially concentrated nitric acid alone as the nitrating agent. The presence to sulfuric acid or other dehydration agent in an amount in excess of about 20% by weight, such as would be encountered in the mixed acid technique, interferes with the selectivity of the nitration to mononitrobenzene and dinitrotoluene. For example, the presence of sulphuric acid will lead to higher formations of mononitrotoluene and dinitrobenzene. For these reasons, it is preferred to use a nitration medium comprising only nitric acid as the nitrating medium.
Nitric acid concentrations for effecting nitration should be from about 82 to 95% by weight and preferably 86 to 92%. When the concentration of nitric acid falls below about 82%, then nitration conditions typically have to be more rigorous in terms of temperature or in terms of increased reaction time. The use of these conditions often leads to increased by-product formation, e.g. dinitrobenzene or a product mix of mono and dinitrotoluene. On the other hand, as the concentration of nitric acid is increased above 95%, e.g. as in the use of fuming nitric acid, no substantial advantages appear to be achieved.
The temperature and reaction time for effecting nitration of the aromatic hydrocarbon is adjusted to accommodate the manufacture of mononitrobenzene and dinitrotoluene in high selectivity without the formation of significant amounts of by-products. Typically, temperatures are from 40° to 70° C. and reaction times of from 2 to 8 minutes are utilized. As previously mentioned as the temperature is increased, there is a tendency to produce undesirable by-products. e.g. dinitrobenzene, and as the temperature is reduced, long reaction times may be required which also permit the formation of increased levels of dinitrobenzene.
Conventional techniques for removing water from the reaction mixture can be utilized in the practice of this invention. These techniques can invoice a process wherein side streams are removed from the reactor, the reaction product then separated into an organic and aqueous phase, and the aqueous phase removed with the organic phase being recycled to the reactor for further reaction. This particular technique permits the nitration to be carried out either in a continuous or batch mode. After the nitration is completed, the reaction product is purified by separating the aqueous phase, including spent nitric acid, from the organic phase and stripped under moderate temperatures to remove volatiles. Optionally, the organic phase can be treated with aqueous alkaline solutions, such as dilute caustic soda or sodium carbonate, to remove undesirable hydrocarbons such as nitrocresols and nitrophenols. However, since it has been observed that there is substantially no tar or undesirable nitrobody formation by the practice of this nitration process, the purification step involving the removal of nitrocresols and other nitrophenolic material may be omitted.
The following examples are provided to illustrate various embodiments of the invention and are not intended to restrict the scope thereof. All parts are parts by weight and all percentages are expressed as weight percentages unless specifically recited otherwise.
EXAMPLE 1
Nitration (Run 1) of a hydrocarbon mixture containing 124.8 grams (1.6 mole) of benzene and 147.2 grams (1.6 mole) of toluene was effected by first charging 50 milliliters of 90 wt % nitric acid into a stirred, glass tank reactor equipped with a stainless steel cooling coil. The benzene-toluene mixture was introduced into the reactor at a rate of 2.3 grams per minute, and the 90% by weight nitric acid being introduced at the rate of 12 grams per minute. After reaction was experienced (by evidence of a slight temperature rise and exothermic conditions), a nitroaromatic-nitric acid-water mixture was continually withdrawn from the apparatus at about the same rate that the benzene-toluene mixture and nitric acid were introduced. The reaction temperature was maintained at 40° C. by removing heat via the stainless steel cooling coils. As the reaction product was removed from the reactor it was quenched by contact with ice. The product then was purified by removing water and spent acid and the organic phase then analyzed by gas chromatographic techniques. Conversion was estimated to be about 100% based upon aromatic compound A similar run to Run 1, i.e., Run 2, was made at 70° C.
The above procedure was repeated as Run 2, except that the temperature of the reaction was maintained at 70° C. as opposed to the 40° C. Table 1 provides gas chromatograph results for both reactions carried out under the above recited conditions. Conversion was estimated to be about 100% based upon hydrocarbon conversion.
TABLE l______________________________________GC Analysis of Benzene-Toluene Nitration with Nitric Acid Run 1 Run 2 T = 40° C. T = 70° C.Compound Mole % Mole %______________________________________Benzene 0 0Toluene 0 0Nitrobenzene 42.75 40.76Nitrotoluenes 1.58 0.55Dinitrobenzene 1.59 5.22Dinitrotoluene 54.09 53.47______________________________________
It can readily be noted from the table at both the 40° C. and 70° C. temperatures that there is high selectivity to a reaction product consisting of mononitrobenzene and dinitrotoluene, particularly at the 40° C. level. Essentially less than 3% of the nitrated product is converted to mononitrotoluene or dinitrobenzene. On the other hand, as the temperature is increased to 70° C. there is a slight increase in the amount of dinitrobenzene produced. However, since this is a dinitrated product, it can be used as a chain extender in other applications where aromatic diamines are suited. It does not present a substantial problem with respect to separation.
EXAMPLE 2
A series of nitration runs using benzene, toluene and xylene as the hydrocarbon feedstock were carried out in accordance with the general technique of Example 1. Numerous process conditions were varied in terms of feed composition, temperature, residence time, and nitration medium in order to observe the effect of the variation in product distribution as a function of these process variables. Table 2 below sets forth the general reaction and process conditions, as well as the product distribution.
TABLE 2__________________________________________________________________________BTX Nitration with Nitric AcidT Res. Time HNO.sub.3 * Acid/Org Mole %Run # (°C.) (min) (wt %) (g/g) MNB DNB MNT DNT DNX TNX__________________________________________________________________________1 50 6.6 92.9 7.0/1.0 29.3 0.18 2.2 59.5 8.74 -- Feed Composition2 75 6.6 92.9 7.0/1.0 26.6 0.85 0.60 63.3 8.21 0.5 28 mole % benzene3 50 6.7 93.1 6.0/1.0 28.3 0.12 10.4 52.2 8.98 -- 63 mole % toluene4 75 6.7 92.1 6.0/1.0 27.6 0.40 3.5 59.9 8.61 -- 9 mole %__________________________________________________________________________ xyleneConitration of Benzene/Nitrotoluene with Mixed Acid Benzene HNO.sub.3 wt % Res. nitrotoluene H.sub.2 SO.sub.4 at steady time T MNB DNB MNT DNTRun # mole ratio mole % state (min) (°C.) (mole %) (mole %) (mole %) (mole__________________________________________________________________________ %)5 1:1 49.3 3.13 8.75 70 51.13 0.36 22.24 26.186 1:1 53.6 3.38 8.75 70 43.42 7.13 1.69 47.76__________________________________________________________________________ *On an organic free basis at the steady state in the CSTR.
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This invention relates to the preparation of a mixture of nitroaromatic compositions, particularly a mixture of mononitrobenzene and dinitrotoluene. The conitration of a mixture of aromatic hydrocarbons is accomplished by contacting the mixture of hydrocarbons with nitric acid, in the absence of sulfuric acid, at temperatures of from about 40° to 70° C. By the use of nitric acid alone, one avoids the heterogeneous nitration associated with the use of sulfuric acid and thereby one can effectively produce a reaction mixture containing mononitrobenzene and dinitrotoluene.
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CROSS-REFERENCE TO RELATED APPLICATION
Applicant hereby claims priority based on Provisional Application No. 60/105,311 filed Oct. 23, 1998, and entitled "Pressure Drop Activated Trap Seal Primer Valve" which is incorporated herein by reference.
FIELD OF INVENTION
The present invention relates to a trap seal primer valve for providing a water charge to a sewer line water trap in response to a change in water line pressure.
BACKGROUND OF THE INVENTION
Trap seal primer valves are used for charging water into sewer line water traps to prevent the escape of sewer gases. Under normal conditions, the level of water in sewer line traps decreases through evaporation by about one-eighth of an inch for each twenty-four hour period. Accordingly, most municipal plumbing and sanitary codes require that means be provided for supplying water to the traps automatically or periodically to assure that the trap water level will be sufficiently high to render the trap operative and functional at all times.
To supply water to the traps automatically, it is usual to connect the trap to the house water line through a priming valve that is actuated by variations in pressure in the house line and acts to charge the trap with water upon each fluctuation of pressure in the house line. These primer valves are required to operate over long periods of time with minimum maintenance.
Many difficulties are associated with the use of conventional trap seal primers. Some of the primers require adjustment to the line pressure in order to function. Others require awkward adjustment to provide the desired metered amount of water. Also, some of the prior art units have an internal screen filter to contain calcium, iron, and other deposits that occur in municipal water supplies. When these filters become clogged, flow is constrained and disassembly of the trap seal primer may render it inoperable. Finally, moving parts in primers are subject to corrosion and failure, especially where springs are involved.
What is needed is a trap seal primer valve for sewer trap lines that does not require any special adjustment for line pressure or amount of water delivery, that dispenses a predictable amount of water in response to a minimal pressure drop (e.g., 3 lb.) occurring in the supply line, that will not flow continuously while the line is returning to normal pressure, that prevents backflow from the trap to the water line, that is simpler in construction and that has an easily replaceable mesh filter and cartridge.
SUMMARY OF THE INVENTION
The present invention meets the above-described need by providing a valve designed to discharge water into a sewer line trap from a water supply line containing water under variable pressures. The valve dispenses a charge of water whenever there is a fluctuation in the water line pressure such as when a faucet is opened.
The valve generally comprises a case having an inlet orifice, an exit orifice, and a chambered cartridge slidably disposed inside the case. The case has a longitudinal bore disposed there through. The inlet orifice is connected to the water line, and the exit orifice of the valve is connected to a sewer trap line. The case has pipe thread fittings on opposite ends for making the necessary plumbing connections.
The case also includes four external wrench flats at each end for assembling, disassembling, and installing the valve. A recessed groove at the inlet orifice provides for installing a fine, mesh filter. A high volume conical fine mesh filter fits into the recessed groove and can be removed and replaced without disassembling the valve.
The case divides into two sections by means of a set of female internal threads at the bottom end that receive a male threaded body end. The male threaded body end has a conical sealing seat disposed above the exit orifice.
A smaller internal bore at the top of the case provides a bearing guide for a cartridge assembly. The cartridge is contained in the longitudinal bore in the body of the device. The cartridge has an upper surface that provides a longitudinal bearing and a top seal. The cartridge is tubular with a partition located at various height positions that provide for various volumes of water discharge. The bottom surface of the cartridge provides a bearing surface for sliding the cartridge. The bottom surface also includes a conical seal for engaging with the conical sealing seat on the end portion.
A recessed groove disposed on the outside of the cartridge near the bottom surface provides an attachment point for a one-way cup seal. The flexible cup seal provides for flow into the lower portion of the case from the house water line, but does not allow backflow. The bottom of the cartridge also has a set of directional cross holes that provide for entry of water into the cartridge as described below.
The partition in the cartridge divides the cartridge into two chambers. The upper chamber is sealed, but the lower chamber has directional cross holes for flow of water into the chamber. When the valve is charge with pressurized water from the water line, the second chamber becomes a compressed air chamber.
At least three different models of the cartridge are contemplated with each model providing a different volume of water charge. By altering the position of the partition, three different volumes of air can be compressed in the lower portion of the cartridge tube.
In operation, the cartridge is slidably disposed inside the bore between a first position and a second position. In the first position, the exit orifice is blocked by engagement of the conical sealing seat with the conical seal on the lower surface of the cartridge. The conical seal engages with the sealing seat because the pressure from the water line on the top of the cartridge forces the lower surface of the cartridge downward into engagement with the conical sealing seat above the exit orifice. With the exit orifice blocked, water flows around the cartridge and into the second chamber of the cartridge until the pressure inside the second chamber reaches equilibrium with the water line pressure. Once this equilibrium position is reached the system remains in this state with no flow of water into the sewer trap line. The valve remains in this configuration until there is a pressure drop.
A pressure drop in the water line causes a pressure differential between the top of the cartridge and the inside of the second chamber such that the cartridge moves away from the exit orifice to allow a charge of water to be released into the sewer trap line. The top diameter of the cartridge is a larger diameter than the bottom cup seal area. Therefore, when the line pressure is imposed on the trap primer valve, a larger area top ensures that the hydraulic pressure differential between the smaller cup seal diameter and the larger top diameter provides a force to seal the conical tip. Next, the house line pressure builds back up and the pressure on the top of the cartridge again pushes the conical seal on the cartridge into engagement with the conical sealing seat to start the recharging process.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated in the drawings in which like reference characters designate the same or similar parts throughout the figures of which:
FIG. 1 is a schematic diagram illustrating the manner of installation of the trap seal primer valve of the present invention;
FIG. 2 is a perspective view of the trap seal primer valve of the present invention;
FIG. 3 is a cut away side elevation view of the trap seal primer valve with the cartridge in a first position where the cartridge shuts off water flow to the exit orifice; and,
FIG. 4 is a cut-away side elevation view of the trap seal primer valve with the cartridge in a second position where the cartridge allows flow of water to the exit orifice.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIG. 1, the seal trap primer valve 10 of the present invention is adapted for insertion into a pressurized water line 13 that interconnects a water line 16 to the sewer trap lines 19. The function of the trap seal primer valve 10 is to keep the sewer trap 22 charged with water so that there is no possibility of the escape of sewer gas 25.
Turning to FIG. 2, the valve 10 is formed out of a cylindrical case 28. The cylindrical case has an inlet orifice 31 that is preferably equipped with a conical, fine mesh screen 37. The top of the case 28 has a set of male pipe threads 38 for connection to the pressurized water line 13. The water pressure from the water line 16 is approximately 60 psi, however, the valve 10 of the present invention can operate at other pressures. The typical operating range would be from about 20 to 80 psi.
Both the top and the bottom of the case 28 are equipped with four wrench flats 40. The wrench flats 40 provide for convenient assembly, disassembly and installation of the valve 10.
The downstream side of the valve 10 is equipped with vent openings 43. The vent/view openings 43 insure that the level of water in the sewer line trap is not disturbed by the development of a vacuum inside the sewer trap line 19.
In FIG. 3, the case 28 has screen 37 at the inlet end. The inlet end has a first cylindrical bore 44 having a first diameter. A second cylindrical bore 45 having a second diameter creates a recessed groove 46. A third cylindrical bore 48 has a third diameter. The screen 37 can be changed and/or removed by simply removing the valve 10 from the water line 13 and lifting the screen out of the recessed groove 46. The screen 37 is preferably a conical, fine mesh, high volume screen suitable for use with water at pressures from 20 to 80 psi.
The inside of the top portion of the case 28 has a cylindrical bore 49 having a diameter smaller than the diameter of the main bore 60. Bore 49 preferably provides a bearing surface for the top of a floating cartridge 52. The cartridge 52 is preferably cylindrical with a sealed top surface 55 and a sealed bottom surface 58. The top surface 55 has a reduced diameter extension 59 that engages with the bearing surface of bore 49 as the cartridge 52 slides up and down inside the case. The extension 59 is preferably formed with cylindrical side walls having rectangular portions removed therefrom. The outside of the cartridge 52 is spaced apart from bore 60. Cylindrical cartridge 52 has a round-shaped top 61 having a slot around its perimeter for receiving the top of the cartridge 52. The top 61 has side walls having an outside diameter that is slightly smaller than the diameter of the bore 60.
Toward the bottom of the case 28, the sidewall 61 of the cylindrical cartridge 52 has a plurality of cross-directional openings 64 disposed therein and located adjacent to the bottom surface 58. The bottom surface 58 preferably includes a cone-shaped seal 67. The cone-shaped seal 67 moves into and out of engagement with a conical sealing seat (described in greater detail below) to cut off fluid communication to the outlet of the case 28.
The lower end of the cartridge 52 has a groove 68 for mounting a one-way cup seal 69. The one-way cup seal 69 permits water to flow downward from the top of the case 28 to the bottom of the case 28, but does not allow water to pass upward. The lower end of the case 28 also has a set of internal female threads 70 that provide for attachment of an end portion 73. In this manner, the valve 10 can be opened by operation of the wrench flats on the bottom of the case 28 to provide for access to the inside of the valve 10 for replacing the cartridge 52.
The top diameter of the cartridge 52 has a larger diameter than the bottom cup seal 69 area. Therefore when the line pressure is imposed on the trap primer valve 10, a larger area top ensures that the hydraulic pressure differential between the smaller cup seal 69 diameter and the larger top diameter provides a force to seal the conical tip.
The end portion 73 has a pair of internal bores 76, 79 (best shown in FIG. 4); an exit orifice 82; and a cone shaped sealing seat 85 (best shown in FIG. 4) positioned above the exit orifice 82. The bore 76 mates with a lower section of the cartridge 52, and the bore 79 is a precision bore for engagement with the cup seal 69. The end portion 73 has a channel 88 for insertion of an O-ring 91 to seal the valve 10.
The cartridge 52 is divided into a first chamber 100 and a second chamber 103 by a partition 106. The first chamber 100 is completely sealed. The second chamber 106 provides an air compression chamber. The second chamber is open to the case 28 through the cross-directional openings 64 that are located around the perimeter of the cartridge 52. When the case 28 is being charged with water, the water flows around the cartridge 52 and into the second chamber 103 through the openings 64. The water inside the second chamber 103 compresses the air that resides in the chamber 103. By altering the position of the partition 106, a different volume of water charge can be obtained. Larger volume in the second chamber 103 produces greater volume water charges. Alternately, the second chamber 103 can be sized such that a partition and a first chamber 100 are not necessary. The purpose of the partition is to define the size of the second chamber.
In operation, the cartridge 52 is slidably disposed inside the bore between a first position and a second position. In the first position shown in FIG. 3, the exit orifice 82 is blocked by engagement of the conical sealing seat 85 with the conical seal 67 on the lower surface of the cartridge 52. The conical seal 67 engages with the sealing seat 85 because the pressure from the water line 13 on the top of the cartridge 52 forces the lower surface of the cartridge 52 downward into engagement with the conical sealing seat 85 above the exit orifice 82.
With the exit orifice 82 blocked, water flows around the cartridge 52, past the cup seal 69, and into the second chamber 103 of the cartridge 52 until the pressure inside the second chamber 103 reaches equilibrium with the water line 13 pressure. Once this equilibrium position is reached, the system remains in this state with no flow of water from the exit orifice 82 into the sewer trap line 19. The valve 10 remains in this configuration until there is a pressure drop.
Referring to FIG. 4, a pressure drop in the water line 13 causes a pressure differential between the top of the cartridge 52 and the inside of the second chamber 106 such that the cartridge 52 moves away from the exit orifice 82 into the second position to allow a charge of water to be released into the sewer trap line 19. When the cartridge 52 moves upward to open the exit orifice 82, the area inside the case 28 below the cartridge 52 is exposed to atmospheric pressure due to communication with the vent/view openings 43 and therefore, the water flows into the sewer trap line 19.
Next, the house line 16 pressure builds back up and gradually, the pressure on the top of the cartridge 52 from line 13 again pushes the cartridge 52 downward such that the conical seal 67 engages with the conical sealing seat 85 to start the recharging process.
While the invention has been described in connection with certain preferred embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
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A trap seal primer valve for automatically charging water into a sewer line trap from a water line containing water under variable pressure.
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TECHNICAL FIELD
This invention relates in general to direct digital synthesizer (DDS) circuits that are based on a digital-to-time converter (DTC) and more particularly to the use of dither to reduce spurs in the spectrum of the DDS output.
BACKGROUND
A direct digital synthesis (DDS) synthesizer circuit often incorporates a digital-to-time converter (DTC) to produce a square wave at its output. The output of the DDS based on a DTC can be used in a radio transceiver to provide a local oscillator (LO) signal. Although common problems often associated with using a DDS involve a tolerable spurious emissions level (spurs) and noise floor, the use of DDS in a radio transceiver also offers many benefits since the DDS output frequency can be tuned over a very wide range with zero lock time.
With regard to spurious emissions by the DDS, there are two sources of error that cause spurs in the spectrum of the output square wave. These sources of error include both mismatch error and quantization error. Mismatch error refers to the DTC error that is due to process mismatch delay and locked loop error. Quantization error is the error or distortion introduced through the quantization process. Although there are existing methods that use dither to eliminate the contribution of the quantization error to the spurs it does nothing to mitigate the mismatch error. As is well known in the art, dithering is done by adding noise of a level less than the least-significant bit before rounding. The added noise has the effect of spreading the many short-term errors across the spectrum as broadband noise. Small improvements can be made to a dithering algorithm such as shaping the noise to areas where it is less objectionable, but the process remains simply one of adding the minimal amount of noise necessary to increase performance.
One example of this type of dithering approach is shown in U.S. Pat. No. 4,933,890 which is herein incorporated by reference. Prior art FIG. 1 illustrates a DDS 100 used for quantizing the output of a digital block 101 . A low level noise, or dither, is injected using a dither source 103 to an adder 105 in order to eliminate the quantization error from being periodic. The quantizer 107 rounds the sum of the digital block 101 and dither source 103 to the nearest multiple of 2 −m , where m is the bit width of the input of the DTC 111 .
Prior art FIG. 2 shows timing diagrams for the DDS 100 . Line A shows the reference clock. Line B shows the v(n) output of the digital block 101 , a succession of fractional numbers with k bits after the point. Line C shows the en 1 (n) output of the digital block, an enable signal for indicating clock cycles that are enabled to produce a pulse. The outputs of the digital block, v(n) and en 1 (n), describe a pulse waveform that can be considered an ideal (no quantization or mismatch error) version of the output of the synthesizer. The signal v(n) is proportional to the pulse delays for the pulses contained in the ideal pulse waveform. Line D shows the ideal pulse waveform. It consists of a train of pulses. The pulse width equals T clk /2, the same as the pulse width of the reference clock. The rising edges of the pulses are delayed with respect to the rising edges of the reference clock, where the amounts of delay are proportional to the values of v(n). The changes, i.e. updates, in the signals v(n) and en 1 (n) occur at rising edges of the reference clock. In the interval between 2 rising clock edges, the ideal pulse waveform contains a rising edge only if en 1 (n)=1. It can be said that en 1 (n)=1 enables the cycle to produce a pulse, and to position the rising edge of the pulse in time before the end of the cycle. Specifically the pulse is positioned so the time delay from the rising edge of the clock to the rising edge of the pulse equals v(n)×T clk . v(n) is a fractional number between 0 and 1-2 −k .
The bit width of the output of the digital block, k, sets the resolution for delaying the pulses in the idealized pulse waveform, i.e. setting the period of the idealized pulse waveform. In the example waveform of FIG. 2 , line D, the period is (1+3/32)×T clk . The period, T out , is limited by the resolution for setting the period and by T clk ≦T out ≦max{T out }. The maximal T out , i.e. max{T out }, is due to some hardware or software consideration as will depend on the implementation. Since the output frequency of the idealized pulse waveform, F out , is the inverse of T out , k also sets the resolution for setting F out in the range min{F out }≦F out ≦F clk , where min{F out }=(max{T out }) −1 .
The bit width of the output of the digital block, k, exceeds the bit width of the input of the DTC, m. In FIG. 2 , k=5 because the output of the digital block v(n) is a succession of 5-bit binary numbers (fractional numbers with denominator 2 5 or 32) and m=3 because the input of the DTC w(n) is a succession of 3-bit binary numbers (fractional numbers with denominator 2 3 or 8.) Although FIG. 2 is for illustration purposes, a typical application in practice is likely to have bit widths greater than k=5 and m=3. Since the bit width of the output of the digital block exceeds the bit width of the input of the DTC quantization is a requirement, and is carried out by the dither source 103 , summer 105 , and quantizer 107 as described herein. Because of the quantization, exact timing is not maintained in terms of the pulse delay times. This timing error causes jitter, and the quantization error energy appears in the spectrum of the output of the DTC. Note, however, that the output of the DTC has the same frequency resolution as the idealized pulse waveform, and as mentioned above, this resolution is set by the bit width of the digital block output v(n).
As noted herein, the quantizer 107 rounds the sum of the digital block 101 and dither source 103 . Lines E and F show the 2's complement outputs of the dither source and summer. The dither source is a discrete random variable uniformly distributed in the range −2 −m−1 ≦d(n)<2 −m−1 .
It will be recognized by those skilled in the art that the limits of the range are plus/minus one-half quantization interval, or 2 −4 =1/16 in FIG. 2 . Line F shows the 2's complement output of the summer 105 . As an example, in the second cycle in FIG. 2 v(n)=3/32. Then v(n)+d(n) is in the range 1/32≦v(n)+d(n)<5/32, and since the quantizer rounds to the nearest multiple of 2 −m , or 1/8, it follows that q(n)=0 or 1/8.
Thus, it can be shown that the probability that the quantizer rounds to q(n)=0 is 1/4 and to q(n)=1/8 is 3/4. In the ensemble average of cycles with v(n)=3/32, the average error is calculated as −3/32×(1/4)+1/32×(3/4)=0.
Those skilled in the art will further recognize that in the ensemble average of a large number of cycles the timing error due to quantization approaches zero. Due to rounding, the quantizer output range is 0 to 1.000 and requires a digit in front of the point. For the DTC input, on the other hand, there is no digit in front of the point and the range is 0 to the binary number 0.111, representing 7/8. w(n)=1.000 is not a valid DTC input. w(n)=1.000 is not typically a valid DTC input for implementations of DTC since if it were valid, it would correspond to a pulse delayed by T clk , i.e., one clock period, with respect to the rising edge of clock cycle n. An equivalent pulse can also be produced with w(n+1)=0, i.e. a delay of zero with respect to the rising edge of clock cycle n+1. The signals q(n) and en 1 (n) couple to the input of the DTC through the modulo block 109 . Lines H and I in FIG. 2 show the outputs of the modulo block. In a cycle in which q(n) does not equal 1.000 or don't_care, the modulo block behaves as a transparent pass-through. In other words in such a cycle w(n)=q(n) and en 2 (n)=en 1 (n). In a cycle in which q(n)=1.000 the modulo block outputs w(n)=don't_care and en 2 (n)=0. Furthermore, in the next clock cycle, cycle # n+1, the modulo block outputs w(n+1)=0 and en 2 (n+1)=1. In a cyle in which q(n)=don't_care, the modulo block passes-through w(n)=don't_care and en 2 (n)=en 1 (n)=0 UNLESS q(n−1)=1.000 in the prior clock cycle.
Finally, a high resolution digital-to-time converter (DTC) 111 is used to finely locate each edge of the output signal 113 at the correct instant in the time domain. As is well known in the art, the time resolution of the DTC 111 directly determines the spectral purity of output signal 113 . The output signal 113 is a square wave whose spectrum contains spurs and measurable noise floor. The DTC produces a pulse at the output, delayed with respect to the reference clock. Line J of FIG. 2 shows that the width for the pulses is Tclk/2. The ideal amount of time delay may be measured from the rising edge of the reference clock to the rising edge of the output pulse and equals w(n)×T clk .
The mathematical sum of the ideal waveform in line D in FIG. 2 and quantization error shown in Line K, as well as the other error terms such as DTC mismatch error, equals the actual synthesizer output, Out(t). As shown in line K, the quantization error has no pattern. Any pattern in the quantization error would cause spectral lines, or spurs, in the spectrum of Out(t). The dither eliminates the quantization error from having a pattern and therefore eliminates the quantization error from contributing to spurs in the spectrum of Out(t). DTC error is the error in the delay time of the output pulses due to DTC non-idealities. Two types of DTC error are DTC mismatch error and DTC thermal noise or device noise error. DTC mismatch error refers to error that has a discrete distribution, i.e. finite set of possible values, and is correlated with w(n), the signal at the input of the DTC. The DTC mismatch error can for example be due to finite matching accuracy for taps in a DTC implemented using a tapped delay line. For each element in the set of possible w(n) there is an associated element in the set of possible mismatch error values. The mismatch error for a pulse generated in response to w(n) in one cycle equals the element associated with the value of w(n) in the cycle with a probability of 1.0. The DTC thermal noise on the other hand is random, not correlated with w(n). While the dither in the prior art system eliminates the contribution of the quantization error to the spurs, it does nothing to reduce the contribution of the mismatch error to the spurs.
One problem associated with the system as seen in FIG. 1 is that it uses dither where the maximum spur level depends on the DTC error. In a radio receiver, achieving spurious emissions low enough to use the DDS to produce the LO signal requires an extremely accurate DTC. Using current technology, such an accurate DTC is not practical making the prior art system very difficult to use in practical applications.
Therefore, the need exists to provide a DDS with improved quantization error and mismatch to reduce overall spurious emissions.
SUMMARY OF THE INVENTION
The present invention is directed to an improved type of dither that works not only to eliminate the contribution of the quantization error to spurious emissions in a direct digital synthesizer, but also reduces the contribution of the mismatch error to any spurious emissions. In accordance with the invention, the output of a digital block is used to compute an address into table of a random access memory (RAM).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a prior art block diagram showing the use of dither in a direct digital synthesizer (DDS).
FIG. 2 is a prior art timing diagram for DDS shown in prior art FIG. 1
FIG. 3 is a block diagram showing introduction of the dither to reduce digital-to-time converter error in accordance with the invention.
FIG. 4 is a time line graph illustrating ideal delay versus address, ideal delay versus input and actual delay versus input for the digital-to-time converter (DTC) shown in FIG. 3 .
FIG. 5 is an alternative embodiment of the system and method for reducing DTC error as shown in FIG. 3 .
FIG. 6 is yet another alternative embodiment of the system and method for reducing DTC error as shown in FIG. 3 .
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.
When the timing error for the pulse delays in the DTC output is dominated by quantization error, the prior art dither works to significantly reduce spurs in the spectrum of the synthesizer output through two aspects. First, as described herein, the prior art system breaks up the patterns in the timing error associated with the output pulses that are produced by the synthesizer. Specifically, the synthesizer breaks up patterns in the timing error due to quantization, although it cannot break up patterns in the timing error due to DTC mismatch. Second, as also described herein, in the ensemble average of a large number of output cycles the timing error due to quantization approaches zero. Unfortunately, as the DTC mismatch error increases in magnitude compared to the quantization error, the prior art dither increasingly fails to achieve those two aspects. The prior art dither eliminates the contribution of the quantization error to the spurs, but cannot reduce the contribution of the DTC mismatch error.
This problem is overcome in the present invention by providing a lookup table that maps from 2 k equally spaced delays to 2 k values for combining with the dither source. As in the prior art system, the digital block output v(n) corresponds to the amount of delay for one pulse in the idealized pulse waveform. In a cycle in which en 1 (n)=1 (and therefore v(n) is not equal to don't_care) the circuit fetches the look-up table value corresponding to the value of v(n) in the cycle. The fetched value then is combined with the dither source and quantized, and the quantizer output is asserted on the DTC input. The statistics of the quantizer output are controlled by the fetched value. If the fetched value is between two quantization levels, then the value at the quantizer output has a probability P of equaling the quantization level to the left, and a probability 1−P of the one to the right. The look-up table value sets the value of P. Assuming the same value of v(n) occurs in other cycles as well, the average delay for a large collection of cycles containing the value of v(n) is g x ×P+g x+2 −m ×(1−P), where g x is the actual (including mismatch error) delay the DTC produces for w(n)=x and g x+2 −m is the actual delay it produces for w(n)=x+2 −m . The table value that was fetched controls P, and therefore the average delay. The look-up table value is set as accurately as possible to yield average delay that approaches the ideal amount of delay, i.e. v(n)×T clk .
The values to load in the look-up table are found by first measuring pulse delay at the DTC output versus value of the DTC input, w(n). The measurements are then used in calculations that provide look-up table values. The DTC measurements, look-up table value calculations, and loading the look-up table might be performed one time during manufacture. Alternatively, the device might contain circuits that automatically measure the DTC where a microprocessor is used for calculating the table values and loading the table. This circuit might operate periodically, updating the table at intervals as temperature or supply voltage might change the characteristics of the DTC. If interrupting the synthesizer output is required in order to update the table values, the update might occur in for example the inter-packet time.
Referring now to FIG. 3 , a DDS 300 includes a digital block 301 that works to supply a number that is k bits wide which is input to a multiplier 303 . As in the prior art system, the outputs of the digital block, v(n) and en 1 (n), describe a pulse waveform that can be considered an ideal (unquantized, zero-error) version of the output of the synthesizer. In the interval between 2 rising clock edges, the ideal pulse waveform contains a rising edge only if en 1 (n)=1. It can be said that en 1 (n)=1 enables the cycle to produce a pulse, and to position the pulse in time so the rising edge occurs before the end of the cycle. The delay between the rising clock edge and the rising edge of the pulse equals v(n)×T clk , where v(n) is a fractional number between 0 and 1-2 −k . While the RAM requires an integer value at the input, v(n) is a fractional number, so the multiplier works to provide the integer found by shifting the point in v(n) k binary digits. The coefficient of the multiplier is a power of 2, hence the multiplier can be realized by a hardwired shift. The output of the digital multiplier 303 is used as a digital address into a random access memory (RAM) 305 . The output of the RAM 305 is supplied to an adder 309 which adds in the dither source 307 . The output of the adder 309 is then supplied to the quantizer 311 , modulo block 313 and the DTC 317 .
As seen in FIG. 4 , a time line graph illustrates ideal delay versus address, ideal delay versus the input to the DTC 317 and actual delay versus the input to the DTC 317 as shown in FIG. 3 . Line A shows the ideal amount of time delay for the pulse in the idealized pulse waveform versus address for digital block output width, k, equal to 5. As described above, the pulse in the idealized version of the synthesizer output is positioned so the time delay from the rising edge of the clock to the rising edge of the pulse equals v(n)×T clk , or addr×2 −k ×T clk . Let D(addr)=addr×2 −k ×T clk denote the ideal delay for address addr. Line B shows the ideal amount of time delay for the pulse the DTC produces versus the DTC input, w(n), for DTC input width, m, equal to 3. The ideal delay from the rising edge of the clock to the rising edge of the output pulse equals w(n)×T clk , where w(n) ranges from 0 to 1-2 −m . Line C of FIG. 4 shows what the actual delay might be where the delay periods are not evenly spaced. Thus the time line shows for 0 to 7 input values to the DTC 317 , what amount of delay the DTC actually produces.
The procedure for calculating the lookup table values is outlined below. When the procedure is followed for address 7, as an example, the table value to load at address 7 captures the following information. The ideal time delay corresponding to address 7 occurs in the interval between the actual DTC delays for w(n)=1/8 and w(n)=2/8, as indicated by an arrow 401 in FIG. 4 . The other information captured in the table value to load at address 7 is the ratio between the following 2 delta-time values: the difference between D(addr=7) and the actual DTC delay for w(n)=1/8 and the difference between actual DTC delay for w(n)=2/8 and for w(n)=1/8.
Through one-time setup at the factory, or periodically during operation, the DTC is measured. This is carried out either using measurement equipment at the factory or using on-chip circuits specially designed to measure the DTC. Specifically, what is measured is pulse delay at the DTC output versus value of the DTC input, w(n). FIG. 4 Line C shows an example of measurement data that might be collected. After collecting the measurements the table values can be computed.
For each address, the value stored at the address is computed as
value
(
addr
)
=
x
+
2
-
m
(
D
(
addr
)
-
g
x
g
x
+
2
-
m
-
g
x
)
=
x
+
2
-
m
ɛ
where k is the bit width of the output of the digital block. In FIG. 4 k=5.
m is the bit width of the input of the DTC. In FIG. 4 m=3.
D(addr)=addr×2 −k ×T clk as defined above. By way of examples, in FIG. 4 D(7)=7/32×T clk and D(20)=20/32×T clk .
x=the largest value that can be applied to the DTC input, i.e. the largest w(n), without the DTC producing a pulse delay larger than D(addr). The actual pulse delays and D(addr) are plotted together on a time line, as in FIG. 4 , and the delay to the left of or exactly coincident with D(addr) is found. Then x is the w(n) corresponding to this point. By way of examples, in FIG. 4 x=1/8 for addr=7 and x=4/8 for addr=20.
g x =actual delay the DTC produces for w(n)=x.
g x+2 −m =actual delay the DTC produces for w(n)=x+2 −m IF
x+ 2 −m <1.000
OR Tclk IF
x+ 2 −m =1.000.
This equation is designed to achieve a behavior where the ideal delay for the pulse at the DTC output is D(addr) and the quantizer randomly picks either w(n)=x or w(n)=x+2 −m , where picking w(n)=x results in a pulse delayed by less than the ideal and w(n)=x+2 −m results in a pulse delayed by greater than the ideal. Those skilled in the art will recognize that the output of the quantizer dithers between the two quantization levels that bracket, i.e. surround, the unquantized value.
The value stored at the address is in the range [x, x+2 −m ). Since the dither ranges over −2 −m−1 ≦d(n)<2 −m−1 and the quantizer quantizes to the nearest multiple of 2 −m , it can easily be shown that the output of the quantizer either equals w(n)=x or w(n)=x+2 −m . The exception is when the value stored at the address is exactly equal to x. In this case the probability is 1.0 that the quantizer quantizes to w(n)=x.
The quantizer output has a probability, P, of equaling the level to the left of ideal, i.e. w(n)=x, and a probability 1−P of equaling the level to the right, i.e. w(n)=x+2 −m . It can be shown that since the dither is a discrete random variable uniformly distributed over the range −2 −m−1 ≦d(n)<2 −m−1 it follows that P equals 1−ε. The definition of ε is embedded in the equation above. Note that this result, i.e. that P=1−ε, assumes that the bit width of the dither source exceeds the bit width of the word stored at the RAM address. Furthermore, epsilon equals the ratio between the following 2 delta-time values: the difference between D(addr) and the actual DTC delay for w(n)=x and the difference between actual DTC delay for w(n)=x+2 −m and for w(n)=x. Clearly 0≦ε<1. Note that ε occupies the h-m least significant bits of the word stored in the RAM, and x occupies the m most significant bits.
For every table value stored in the RAM there is a corresponding value of ε and of P=1−ε. By way of example, for address 7 there is a corresponding value of P=1−ε. There is also a corresponding value of x, the quantization level to the left. The average delay obtained in cycles in which the address equals 7 is g x ×P+g x+2 −m ×(1−P), where g x , as defined above, is the delay that is actually obtained (including mismatch error) when w(n)=x and g x+2 −m is the delay actually obtained when w(n)=x+2 −m . In other words, the average delay over a collection of an infinite number of cycles in which address equals 7, is given by g x ×P+g x+2 −m ×(1−P). The average delay (computed with this expression) equals the ideal delay, D(addr=7), to a good accuracy assuming good measurements. In the limit as the measurements are perfect, and the bit width of the RAM word is infinite, the average delay approaches the ideal delay. It can be shown that the level of the highest spur in the spectrum of the synthesizer output depends on the accuracy of the lookup table, while the accuracy of the lookup table depends on the accuracy of the measurements.
The value of ε, which as mentioned above is held in the least significant bits of the word stored in the RAM, controls P. x and ε together control the average delay. The value of ε is found using the above equation, using the measurements taken on the DTC.
In the DDS 300 shown in FIG. 3 the modulo block 313 has the same functionality as in the prior art DDS. In a cycle in which q(n)=1.000 the modulo block outputs q(n)=don't_care and en 2 (n)=0. Furthermore, in the next clock cycle, cycle # n+1, the modulo block outputs q(n+1)=0 and en 2 (n+1)=1. Thus q(n)=1.000 produces q(n+1)=0.000 in cycle n+1, corresponding to a pulse delayed by T clk with respect to the rising edge of clock cycle n. For this reason, the definition of g x+2 −m contains an IF statement that sets g x+2 −m equal to T clk if x=1-2 −m .
If the DTC mismatch error is not severe, x in the above equation might be as an example 7/8 for the range of addresses from 27 to 31 or 28 to 31. It should be noted that for x=7/8, x+2 −m =8/8=1. In cycles in which the address is in the range for x=7/8, w(n) dithers between 7/8 in cycle n and 0 in cycle n+1.
If the DTC mismatch error is severe, x in the above equation might be as an example 5/8 even for address=31. This represents a DTC where the delays are significantly larger than nominal. In cycles that have address=31, w(n) dithers between 5/8 and 6/8. The modulo block behaves as a transparent pass-through 100% of the time, since RAM output r(n) never equals 1.000.
In another case where DTC mismatch error is severe, x might be say 7/8 for the entire range of addresses from e.g. 20 to 31. In a cycle that has address in this range, w(n) dithers between 7/8 in cycle n and 0 in cycle n+1.
In the description of an ideal DTC defined herein, the delay for the pulse at the output is zero for w(n)=0, where delay is measured from the rising edge of the clock. In other words for w(n)=0 the rising edge of the output pulse aligns with the rising edge of the reference clock. This is not the only possible identification of ideal delay for w(n)=0, and a different approach might be convenient for certain applications.
For some applications, alignment of the synthesizer output with the reference clock, i.e. the phase with respect to the reference clock, might not be important. The only requirement for the output signal might be the spectral purity, in other words the timing error for spacing the pulses evenly in time. In this case it is convenient to consider the actual delay the DTC produces for w(n)=0 as the ideal delay, for the purpose of computing the RAM table values. In FIG. 3 the ideal delay for w(n)=0 would still align with the actual delay for w(n)=0 even if this would mean it does not align with the rising edge of the reference clock. Note however that once the ideal delay for w(n)=0 is established, there is no flexibility for identifying the ideal delay for w(n) not equal to zero, i.e. the w(n) other than w(n)=0. To maintain spectral purity, the ideal delay versus w(n) are required to be spaced evenly in time at intervals of 2 −m ×T clk , as shown in FIG. 4 . Furthermore, once the ideal delay for w(n)=0 is established, there is no flexibility for identifying the ideal delay versus address. The ideal delay for address=0 aligns with the ideal delay for w(n)=0, as shown in FIG. 4 . The ideal delay versus address are required to be evenly spaced in time at intervals of 2 −k ×T clk , as also shown in FIG. 4 .
Even if the phase with respect to the reference clock is important, there is some flexibility for the method of computing the RAM table values. By way of example, two sequences that produce F out =2/3×F clk are v 1 (n)=0,16,x,0,16,x . . . and v 2 (n)=30,x,14,30,x,14, . . . Suppose for example the RAM look-up table values are computed with ideal delay for w(n)=0 identified as zero with respect to the rising edge of the reference clock. In other words, identifying the ideal pulse produced with w(n)=0 as aligned with the rising edge of the reference clock. The output of the synthesizer with v 1 (n) is guaranteed to have edges aligning with the edges of the reference clock (assuming the measurements used in the lookup table calculations are accurate.) Now suppose the RAM table values are computed with the delay the DTC actually produces for w(n)=0 considered the ideal delay for the purpose of computing the RAM table values. The output of the synthesizer with v 2 (n) might actually have edges closer to aligning with the clock edges than with v 1 (n). The digital block can be implemented with control logic that steers the phase by outputting for example the sequence v 2 (n) instead of v 1 (n).
Thus, the invention involves providing a look-up table within the RAM 305 that maps from 2 k equally spaced delays to 2 k values for combining with the dither source. The values stored in the look-up table are computed based upon measurements of a DTC 317 . The spurious emission levels produced by the DDS 300 will depend on the accuracy of the look-up table while the accuracy of the lookup table will depend on the accuracy of the measurements of DTC 317 . The invention as described herein applies when mismatch error is a value other than zero, and unlike the prior art form of dither, is of utility even if the bit width of the digital block output does not exceed the bit width of the DTC input. If the DDS 100 of prior art FIG. 1 produces a modulated sequence at the digital block output and therefore a FM/PM modulated square wave at the DDS output 113 , the mismatch error is not periodic. However, if the spectrum of the square wave output 113 were measured with a spectrum analyzer it is still likely spurs due to mismatch error would be observed. This depends on the spectrum analyzer settings that are specified for measuring the spurs. The time that the spectrum analyzer spends in each resolution element depends on the sweep time and other parameters. A method of reducing mismatch error spurs often remains a requirement when the DDS output is modulated.
FIG. 5 illustrates an alternative embodiment of the invention depicting a direct digital synthesizer 500 that works to provide means to reduce the length of the RAM, i.e., number of addresses. The output of the digital block 501 is rounded to the bit width of the RAM 511 address. As compared with FIG. 3 , this is achieved using an additional dither source 503 and quantizer 507 . For example, if the RAM 511 is a 32 address RAM, then the quantizer 507 would round the output of the adder 505 to 5 bits. This would then be input to multiplier 509 and supplied to the RAM 511 . The data output of the RAM 511 is then fed to adder 515 which combines dither source 513 to provide j bits to quantizer 517 . As noted herein, quantizer 517 provides a number ranging from 0 to 1, inclusive, to a modulo block 519 . In a cycle in which q(n)=1.000 the modulo block outputs w(n)=don't_care and en 2 (n)=0. Furthermore, in the next clock cycle, cycle # n+1, the modulo block outputs w(n+1)=0 and en 2 (n+1)=1. Thus, there are two stages of quantization. The quantizer 507 quantizes data to the bit width of the RAM 511 input. The second quantizer stage which is quantizer 517 works to quantize the RAM output to the bit width of the required input to the DTC 521 .
FIG. 6 illustrates yet another alternative embodiment of the invention depicting a direct digital synthesizer 600 that provides a RAM for mapping from DTC input values to values combined with a dither source, creating a control signal for one or more delay elements in the signal path in the DTC. The control signal is random, with statistics controlled by the table values.
As noted herein summer 605 combines dither source 603 with the output of digital block 601 to provide a j-bit wide number to quantizer 607 . The quantizer rounds to the nearest multiple of 2 −m producing output signal q(n) applied to modulo block 609 . The modulo block is transparent to all values of q(n) except q(n)=1.000, which it pushes into the next clock cycle. The output of the modulo block is applied to DTC 611 and multiplier 614 . The multiplier supplies the product w(n)×2 −m , an integer, to the address port of RAM 615 and the value stored there is fetched. The summer 617 computes the sum of the fetched value and the dither source 621 . The output of summer 617 is quantized by 2 level quantizer 619 . The 1-bit quantizer output e(n) is applied to control port 610 of DTC 611 .
The signal e(n) at control port 610 controls a single delay element in the signal path in the DTC. In a cycle in which en 2 (n)=1 the DTC produces a pulse delayed by w(n)×T clk +e(n)×δ+mism{w(n)} where e(n) is 0 or 1 and mism{w(n)} is the mismatch error associated with the value of w(n) in the cycle. The delay element controlled by e(n) introduces a delay of δ if e(n)=1, and zero if e(n)=0.
The dither source is uniformly distributed between −½ and ½ and the values stored in the RAM look-up table are between 0 and 1. Thus in cycle # n the probability P(n) that the quantizer outputs 0 is given by P=1−r(n), where r(n) is the value fetched from the RAM in the cycle. The probability is 1−P that the quantizer outputs 1. Say the value fetched from the RAM in a particular cycle is r(n)=tv(7), where tv(7) is the table value stored at address 7. The average pulse delay at the DTC output, computed over the set of all cycles that fetch the value at address 7, equals 2 −m ×7×T clk +(1−P)×δ+mism{w(n)=2 −m ×7} where P=1−tv(7) and the term mism{w(n)=2 −m ×7) is the mismatch error associated with w(n)=2 −m ×7. The look-up table values are computed using measured values of mism {w(n)} and to the degree that the measurements are accurate, and accurate table values are loaded in the RAM, the term (1−P)×δ cancels out the mismatch error term.
In a variation on DDS 600 , the quantizer 619 outputs 0 and −1 where −1 applied to the control port 610 decreases the delay by an amount delta. In another variation, the quantizer 619 is 2-bits wide and outputs 0, 1, and −1. In still another variation, there is more than one delay element in the signal path in the DTC. A multiplexer incorporated in the DTC can use w(n) for a select input and then routes the control signal at port 610 to one of 2 m delay elements. The delay elements provide differing amounts of delta-delay because of mismatch, therefore δ in a particular cycle depends on the particular delay element that is picked in the cycle (and therefore on w(n) in the cycle.)
In summary, the invention defines a new approach to dither that not only eliminates the contribution of the quantization error to spurious emissions, but also reduces the contribution of the mismatch error to these emissions by using at least one dither source and RAM which maps from 2 k equally spaced delays to 2 k values for combining with a dither source.
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.
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A direct digital synthesizer (DDS) ( 300 ) that uses a system for reducing spurious emissions in a digital-to-time converter (DTC) ( 317 ). The DDS ( 300 ) includes one or more dither sources ( 307 ) and a random access memory (RAM) ( 305 ). The RAM ( 305 ) utilizes a look-up table for storing delay error values by using an output of the look-up table which is combined with the dither source ( 307 ) to compensate unequal unit delay values in the DTC ( 317 ).
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TECHNICAL FIELD
The present invention relates to electrically variable transmissions with selective operation both in power-split variable speed ratio ranges and in fixed speed ratios, and having three planetary gear sets, two motor/generators and three or four torque transfer devices.
BACKGROUND OF THE INVENTION
Internal combustion engines, particularly those of the reciprocating piston type, currently propel most vehicles. Such engines are relatively efficient, compact, lightweight, and inexpensive mechanisms by which to convert highly concentrated energy in the form of fuel into useful mechanical power. A novel transmission system, which can be used with internal combustion engines and which can reduce fuel consumption and the emissions of pollutants, may be of great benefit to the public.
The wide variation in the demands that vehicles typically place on internal combustion engines increases fuel consumption and emissions beyond the ideal case for such engines. Typically, a vehicle is propelled by such an engine, which is started from a cold state by a small electric motor and relatively small electric storage batteries, then quickly placed under the loads from propulsion and accessory equipment. Such an engine is also operated through a wide range of speeds and a wide range of loads and typically at an average of approximately a fifth of its maximum power output.
A vehicle transmission typically delivers mechanical power from an engine to the remainder of a drive system, such as fixed final drive gearing, axles and wheels. A typical mechanical transmission allows some freedom in engine operation, usually through alternate selection of five or six different drive ratios, a neutral selection that allows the engine to operate accessories with the vehicle stationary, and clutches or a torque converter for smooth transitions between driving ratios and to start the vehicle from rest with the engine turning. Transmission gear selection typically allows power from the engine to be delivered to the rest of the drive system with a ratio of torque multiplication and speed reduction, with a ratio of torque reduction and speed multiplication known as overdrive, or with a reverse ratio.
An electric generator can transform mechanical power from the engine into electrical power, and an electric motor can transform that electric power back into mechanical power at different torques and speeds for the remainder of the vehicle drive system. This arrangement allows a continuous variation in the ratio of torque and speed between engine and the remainder of the drive system, within the limits of the electric machinery. An electric storage battery used as a source of power for propulsion may be added to this arrangement, forming a series hybrid electric drive system.
The series hybrid system allows the engine to operate with some independence from the torque, speed and power required to propel a vehicle, so the engine may be controlled for improved emissions and efficiency. This system allows the electric machine attached to the engine to act as a motor to start the engine. This system also allows the electric machine attached to the remainder of the drive train to act as a generator, recovering energy from slowing the vehicle into the battery by regenerative braking. A series electric drive suffers from the weight and cost of sufficient electric machinery to transform all of the engine power from mechanical to electrical in the generator and from electrical to mechanical in the drive motor, and from the useful energy lost in these conversions.
A power-split transmission can use what is commonly understood to be “differential gearing” to achieve a continuously variable torque and speed ratio between input and output. An electrically variable transmission can use differential gearing to send a fraction of its transmitted power through a pair of electric motor/generators. The remainder of its power flows through another, parallel path that is all mechanical and direct, of fixed ratio, or alternatively selectable.
One form of differential gearing, as is well known to those skilled in this art, may constitute a planetary gear set. Planetary gearing is usually the preferred embodiment employed in differentially geared inventions, with the advantages of compactness and different torque and speed ratios among all members of the planetary gear set. However, it is possible to construct this invention without planetary gears, as by using bevel gears or other gears in an arrangement where the rotational speed of at least one element of a gear set is always a weighted average of speeds of two other elements.
A hybrid electric vehicle transmission system also includes one or more electric energy storage devices. The typical device is a chemical electric storage battery, but capacitive or mechanical devices, such as an electrically driven flywheel, may also be included. Electric energy storage allows the mechanical output power from the transmission system to the vehicle to vary from the mechanical input power from the engine to the transmission system. The battery or other device also allows for engine starting with the transmission system and for regenerative vehicle braking.
An electrically variable transmission in a vehicle can simply transmit mechanical power from an engine input to a final drive output. To do so, the electric power produced by one motor/generator balances the electrical losses and the electric power consumed by the other motor/generator. By using the above-referenced electrical storage battery, the electric power generated by one motor/generator can be greater than or less than the electric power consumed by the other. Electric power from the battery can sometimes allow both motor/generators to act as motors, especially to assist the engine with vehicle acceleration. Both motors can sometimes act as generators to recharge the battery, especially in regenerative vehicle braking.
A successful substitute for the series hybrid transmission is the two-range, input-split and compound-split electrically variable transmission now produced for transmit buses, as disclosed in U.S. Pat. No. 5,931,757, issued Aug. 3, 1999, to Michael Roland Schmidt, commonly assigned with the present application, and hereby incorporated by reference in its entirety. Such a transmission utilizes an input means to receive power from the vehicle engine and a power output means to deliver power to drive the vehicle. First and second motor/generators are connected to an energy storage device, such as a battery, so that the energy storage device can accept power from, and supply power to, the first and second motor/generators. A control unit regulates power flow among the energy storage device and the motor/generators as well as between the first and second motor/generators.
Operation in first or second variable-speed-ratio modes of operation may be selectively achieved by using clutches in the nature of first and second torque transfer devices. In the first mode, an input-power-split speed ratio range is formed by the application of the first clutch, and the output speed of the transmission is proportional to the speed of one motor/generator. In the second mode, a compound-power-split speed ratio range is formed by the application of the second clutch, and the output speed of the transmission is not proportional to the speeds of either of the motor/generators, but is an algebraic linear combination of the speeds of the two motor/generators. Operation at a fixed transmission speed ratio may be selectively achieved by the application of both of the clutches. Operation of the transmission in a neutral mode may be selectively achieved by releasing both clutches, decoupling the engine and both electric motor/generators from the transmission output. The transmission incorporates at least one mechanical point in its first mode of operation and at least two mechanical points in its second mode of operation.
U.S. Pat. No. 6,527,658, issued Mar. 4, 2003 to Holmes et al, commonly assigned with the present application, and hereby incorporated by reference in its entirety, discloses an electrically variable transmission utilizing two planetary gear sets, two motor/generators and two clutches to provide input split, compound split, neutral and reverse modes of operation. Both planetary gear sets may be simple, or one may be individually compounded. An electrical control member regulates power flow among an energy storage device and the two motor/generators. This transmission provides two ranges or modes of electrically variable transmission (EVT) operation, selectively providing an input-power-split speed ratio range and a compound-power-split speed ratio range. One fixed speed ratio can also be selectively achieved.
SUMMARY OF THE INVENTION
The present invention provides a family of electrically variable transmissions offering several advantages over conventional automatic transmissions for use in hybrid vehicles, including improved vehicle acceleration performance, improved fuel economy via regenerative braking and electric-only idling and launch, and an attractive marketing feature. An object of the invention is to provide the best possible energy efficiency and emissions for a given engine. In addition, optimal performance, capacity, package size, and ratio coverage for the transmission are sought.
The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first, second and third differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, and three or four selectable torque-transfer devices. Preferably, the differential gear sets are planetary gear sets, such as simple or compound (including Ravigneaux) gear sets, but other gear arrangements may be implemented, such as bevel gears or differential gearing to an offset axis.
In this description, the first, second, or third planetary gear sets may be counted first to third in any order (i.e., left to right, right to left, etc.).
Each of the three planetary gear sets has three members. The first, second or third member of each planetary gear set can be any one of a sun gear, ring gear or carrier member, or alternatively a pinion.
Each carrier member can be either a single-pinion carrier member (simple) or a double-pinion carrier member (compound).
The input shaft is continuously connected with at least one member of the planetary gear sets. The output shaft is continuously connected with another member of the planetary gear sets.
A first interconnecting member continuously connects a first member of the first planetary gear set with the first member of the second planetary gear set.
A second interconnecting member continuously connects the second member of the first planetary gear set with the second member of the second planetary gear set.
A third interconnecting member continuously connects a member of the first planetary gear set with a stationary member (transmission housing/casing).
A first torque transfer device selectively connects a member of the first or second planetary gear set with a member of the third planetary gear set.
A second torque transfer device selectively connects another member of the first or second planetary gear-set with another member of the third planetary gear set.
An alternative third torque transfer device selectively connects a member of the first, second or third planetary gear set with a stationary member (transmission housing/casing).
An optional fourth torque transfer device is connected in parallel with one of the motor/generators for selectively preventing rotation thereof.
The first motor/generator is mounted to the transmission case and is connected either continuously to a member of the first or second planetary gear set or selectively via a dog clutch (or equivalently by a pair of clutches) to a member of the first or third planetary gear set. The first motor/generator may also incorporate offset gearing.
The second motor/generator is mounted to the transmission case (or ground) and is continuously connected to a member of the third planetary gear set. The second motor/generator connection may incorporate offset gearing.
The selectable torque transfer devices are engaged in combinations of one or two to yield an EVT with a continuously variable range of speeds (including reverse) and up to three mechanically fixed forward speed ratios. A “fixed speed ratio” is an operating condition in which the mechanical power input to the transmission is transmitted mechanically to the output, and no power flow (i.e. almost zero) is present in the motor/generators. An electrically variable transmission that may selectively achieve several fixed speed ratios for operation near full engine power can be smaller and lighter for a given maximum capacity. Fixed ratio operation may also result in lower fuel consumption when operating under conditions where engine speed can approach its optimum without using the motor/generators. A variety of fixed speed ratios and variable ratio spreads can be realized by suitably selecting the tooth ratios of the planetary gear sets.
Each embodiment of the electrically variable transmission family disclosed has an architecture in which neither the transmission input nor output is directly connected to a motor/generator. This allows for a reduction in the size and cost of the electric motor/generators required to achieve the desired vehicle performance.
The torque transfer devices, and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.
The above features and advantages, and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a is a schematic representation of a powertrain including an electrically variable transmission incorporating a family member of the present invention;
FIG. 1 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 1 a;
FIG. 2 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 2 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 2 a;
FIG. 3 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 3 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 3 a;
FIG. 4 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 4 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 4 a;
FIG. 5 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 5 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 5 a;
FIG. 6 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 6 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 6 a;
FIG. 7 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 7 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 7 a;
FIG. 8 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 8 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 8 a;
FIG. 9 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 9 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 9 a;
FIG. 10 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 10 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 10 a;
FIG. 11 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
FIG. 11 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 11 a;
FIG. 12 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention; and
FIG. 12 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 12 a.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIG. 1 a , a powertrain 10 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission (EVT), designated generally by the numeral 14 . Transmission 14 is designed to receive at least a portion of its driving power from the engine 12 . As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 14 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
In the embodiment depicted the engine 12 may be a fossil fuel engine, such as a diesel engine which is readily adapted to provide its available power output typically delivered at a constant number of revolutions per minute (RPM).
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 14 . An output member 19 of the transmission 14 is connected to a final drive 16 .
The transmission 14 utilizes three differential gear sets, preferably in the nature of planetary gear sets 20 , 30 and 40 . The planetary gear set 20 employs an outer gear member 24 , typically designated as the ring gear. The ring gear member 24 circumscribes an inner gear member 22 , typically designated as the sun gear. A carrier member 26 rotatably supports a plurality of planet gears 27 such that each planet gear 27 meshingly engages both the outer, ring gear member 24 and the inner, sun gear member 22 of the first planetary gear set 20 .
The planetary gear set 30 also has an outer gear member 34 , often also designated as the ring gear, that circumscribes an inner gear member 32 , also often designated as the sun gear member. A plurality of planet gears 37 are also rotatably mounted in a carrier member 36 such that each planet gear member 37 simultaneously, and meshingly, engages both the outer, ring gear member 34 and the inner, sun gear member 32 of the planetary gear set 30 .
The planetary gear set 40 also has an outer gear member 44 , often also designated as the ring gear, that circumscribes an inner gear member 42 , also often designated as the sun gear. A plurality of planet gears 47 are also rotatably mounted in a carrier member 46 such that each planet gear member 47 simultaneously, and meshingly, engages both the outer, ring gear member 44 and the inner, sun gear member 42 of the planetary gear set 40 .
A first interconnecting member 70 continuously connects the sun gear member 22 of the planetary gear set 20 with the sun gear member 32 of the planetary gear set 30 . A second interconnecting member 72 continuously connects the ring gear member 24 of the planetary gear set 20 with the carrier member 36 of the planetary gear set 30 . A third interconnecting member 74 continuously connects the sun gear member 22 of the planetary gear set 20 with the transmission housing 60 .
The first preferred embodiment 10 also incorporates first and second motor/generators 80 and 82 , respectively. The stator of the first motor/generator 80 is secured to the transmission housing 60 . The rotor of the first motor/generator 80 is secured to the ring gear member 34 of the planetary gear set 30 .
The stator of the second motor/generator 82 is also secured to the transmission housing 60 . The rotor of the second motor/generator 82 is selectively connectable to the sun gear member 42 of the planetary gear set 40 .
A first torque transfer device, such as clutch 50 , selectively connects the carrier member 26 of the planetary gear set 20 with the ring gear member 44 of the planetary gear set 40 . A second torque transfer device, such as clutch 52 , selectively connects the ring gear member 34 of the planetary gear set 30 with the ring gear member 44 of the planetary gear set 40 . A third torque transfer device, such as brake 54 , selectively connects the carrier member 26 of the planetary gear set 20 with the transmission housing 60 . A fourth torque transfer device, such as brake 55 , is connected in parallel with the motor/generator 82 for selectively braking rotation thereof. The first, second, third and fourth torque transfer devices 50 , 52 , 54 and 55 are employed to assist in the selection of the operational modes of the hybrid transmission 14 , as will be hereinafter more fully explained.
The input drive member 17 is continuously connected with the carrier member 36 of the planetary gear set 30 . The output drive member 19 of the transmission 14 is secured to the carrier member 46 of the planetary gear set 40 .
Returning now to the description of the power sources, it should be apparent from the foregoing description, and with particular reference to FIG. 1 a , that the transmission 14 selectively receives power from the engine 12 . The hybrid transmission also receives power from an electric power source 86 , which is operably connected to a controller 88 . The electric power source 86 may be one or more batteries. Other electric power sources, such as fuel cells, that have the ability to provide, or store, and dispense electric power may be used in place of batteries without altering the concepts of the present invention.
General Operating Considerations
One of the primary control devices is a well known drive range selector (not shown) that directs an electronic control unit (the ECU 88 ) to configure the transmission for either the park, reverse, neutral, or forward drive range. The second and third primary control devices constitute an accelerator pedal (not shown) and a brake pedal (also not shown). The information obtained by the ECU from these three primary control sources is designated as the “operator demand.” The ECU also obtains information from a plurality of sensors (input as well as output) as to the status of: the torque transfer devices (either applied or released); the engine output torque; the unified battery, or batteries, capacity level; and, the temperatures of selected vehicular components. The ECU determines what is required and then manipulates the selectively operated components of, or associated with, the transmission appropriately to respond to the operator demand.
The invention may use simple or compound planetary gear sets. In a simple planetary gear set a single set of planet gears are normally supported for rotation on a carrier member that is itself rotatable.
In a simple planetary gear set, when the sun gear is held stationary and power is applied to the ring gear of a simple planetary gear set, the planet gears rotate in response to the power applied to the ring gear and thus “walk” circumferentially about the fixed sun gear to effect rotation of the carrier member in the same direction as the direction in which the ring gear is being rotated.
When any two members of a simple planetary gear set rotate in the same direction and at the same speed, the third member is forced to turn at the same speed, and in the same direction. For example, when the sun gear and the ring gear rotate in the same direction, and at the same speed, the planet gears do not rotate about their own axes but rather act as wedges to lock the entire unit together to effect what is known as direct drive. That is, the carrier member rotates with the sun and ring gears.
However, when the two gear members rotate in the same direction, but at different speeds, the direction in which the third gear member rotates may often be determined simply by visual analysis, but in many situations the direction will not be obvious and can only be accurately determined by knowing the number of teeth present on all the gear members of the planetary gear set.
Whenever the carrier member is restrained from spinning freely, and power is applied to either the sun gear or the ring gear, the planet gear members act as idlers. In that way the driven member is rotated in the opposite direction as the drive member. Thus, in many transmission arrangements when the reverse drive range is selected, a torque transfer device serving as a brake is actuated frictionally to engage the carrier member and thereby restrain it against rotation so that power applied to the sun gear will turn the ring gear in the opposite direction. Thus, if the ring gear is operatively connected to the drive wheels of a vehicle, such an arrangement is capable of reversing the rotational direction of the drive wheels, and thereby reversing the direction of the vehicle itself.
In a simple set of planetary gears, if any two rotational speeds of the sun gear, the planet carrier member, and the ring gear are known, then the speed of the third member can be determined using a simple rule. The rotational speed of the carrier member is always proportional to the speeds of the sun and the ring, weighted by their respective numbers of teeth. For example, a ring gear may have twice as many teeth as the sun gear in the same set. The speed of the carrier member is then the sum of two-thirds the speed of the ring gear and one-third the speed of the sun gear. If one of these three members rotates in an opposite direction, the arithmetic sign is negative for the speed of that member in mathematical calculations.
The torque on the sun gear, the carrier member, and the ring gear can also be simply related to one another if this is done without consideration of the masses of the gears, the acceleration of the gears, or friction within the gear set, all of which have a relatively minor influence in a well designed transmission. The torque applied to the sun gear of a simple planetary gear set must balance the torque applied to the ring gear, in proportion to the number of teeth on each of these gears. For example, the torque applied to a ring gear with twice as many teeth as the sun gear in that set must be twice that applied to the sun gear, and must be applied in the same direction. The torque applied to the carrier member must be equal in magnitude and opposite in direction to the sum of the torque on the sun gear and the torque on the ring gear.
In a compound planetary gear set, the utilization of inner and outer sets of planet gears effects an exchange in the roles of the ring gear and the planet carrier member in comparison to a simple planetary gear set. For instance, if the sun gear is held stationary, the planet carrier member will rotate in the same direction as the ring gear, but the planet carrier member with inner and outer sets of planet gears will travel faster than the ring gear, rather than slower.
In a compound planetary gear set having meshing inner and outer sets of planet gears the speed of the ring gear is proportional to the speeds of the sun gear and the planet carrier member, weighted by the number of teeth on the sun gear and the number of teeth filled by the planet gears, respectively. For example, the difference between the ring and the sun filled by the planet gears might be as many teeth as are on the sun gear in the same set. In that situation the speed of the ring gear would be the sum of two-thirds the speed of the carrier member and one third the speed of the sun. If the sun gear or the planet carrier member rotates in an opposite direction, the arithmetic sign is negative for that speed in mathematical calculations.
If the sun gear were to be held stationary, then a carrier member with inner and outer sets of planet gears will turn in the same direction as the rotating ring gear of that set. On the other hand, if the sun gear were to be held stationary and the carrier member were to be driven, then planet gears in the inner set that engage the sun gear roll, or “walk,” along the sun gear, turning in the same direction that the carrier member is rotating. Pinion gears in the outer set that mesh with pinion gears in the inner set will turn in the opposite direction, thus forcing a meshing ring gear in the opposite direction, but only with respect to the planet gears with which the ring gear is meshingly engaged. The planet gears in the outer set are being carried along in the direction of the carrier member. The effect of the rotation of the pinion gears in the outer set on their own axis and the greater effect of the orbital motion of the planet gears in the outer set due to the motion of the carrier member are combined, so the ring rotates in the same direction as the carrier member, but not as fast as the carrier member.
If the carrier member in such a compound planetary gear set were to be held stationary and the sun gear were to be rotated, then the ring gear will rotate with less speed and in the same direction as the sun gear. If the ring gear of a simple planetary gear set is held stationary and the sun gear is rotated, then the carrier member supporting a single set of planet gears will rotate with less speed and in the same direction as the sun gear. Thus, one can readily observe the exchange in roles between the carrier member and the ring gear that is caused by the use of inner and outer sets of planet gears which mesh with one another, in comparison with the usage of a single set of planet gears in a simple planetary gear set.
The normal action of an electrically variable transmission is to transmit mechanical power from the input to the output. As part of this transmission action, one of its two motor/generators acts as a generator of electrical power. The other motor/generator acts as a motor and uses that electrical power. As the speed of the output increases from zero to a high speed, the two motor/generators 80 , 82 gradually exchange roles as generator and motor, and may do so more than once. These exchanges take place around mechanical points, where essentially all of the power from input to output is transmitted mechanically and no substantial power is transmitted electrically.
In a hybrid electrically variable transmission system, the battery 86 may also supply power to the transmission or the transmission may supply power to the battery. If the battery is supplying substantial electric power to the transmission, such as for vehicle acceleration, then both motor/generators may act as motors. If the transmission is supplying electric power to the battery, such as for regenerative braking, both motor/generators may act as generators. Very near the mechanical points of operation, both motor/generators may also act as generators with small electrical power outputs, because of the electrical losses in the system.
Contrary to the normal action of the transmission, the transmission may actually be used to transmit mechanical power from the output to the input. This may be done in a vehicle to supplement the vehicle brakes and to enhance or to supplement regenerative braking of the vehicle, especially on long downward grades. If the power flow through the transmission is reversed in this way, the roles of the motor/generators will then be reversed from those in normal action.
Specific Operating Considerations
Each of the embodiments described herein has thirteen to fifteen functional requirements (corresponding with the 13 to 15 rows of each operating mode table shown in the Figures) which may be grouped into five operating modes. These five operating modes are described below and may be best understood by referring to the respective operating mode table accompanying each transmission stick diagram, such as the operating mode tables of FIGS. 1 b , 2 b , 3 b , etc.
The first operating mode is the “battery reverse mode” which corresponds with the first row (Batt Rev) of each operating mode table, such as that of FIG. 1 b . In this mode, the engine is off and the transmission element connected to the engine is not controlled by engine torque, though there may be some residual torque due to the rotational inertia of the engine. The EVT is driven by one of the motor/generators using energy from the battery, causing the vehicle to move in reverse. Depending on the kinematic configuration, the other motor/generator may or may not rotate in this mode, and may or may not transmit torque. If it does rotate, it is used to generate energy which is stored in the battery. In the embodiment of FIG. 1 b , in the battery reverse mode, the clutch 50 and brake 54 are engaged, the generator 80 has zero torque, the motor 82 has a torque of −1.00, and a torque ratio of −3.25 is achieved, by way of example. In each operating mode table an (M) next to a torque value in the motor/generator columns 80 and 82 indicates that the motor/generator is acting as a motor, and the absence of an (M) indicates that the motor/generator is acting as generator.
The second operating mode is the “EVT reverse mode” (or mechanical reverse mode) which corresponds with the second row (EVT Rev) of each operating mode table, such as that of FIG. 1 b . In this mode, the EVT is driven by the engine and by one of the motor/generators. The other motor/generator operates in generator mode and transfers 100% of the generated energy back to the driving motor. The net effect is to drive the vehicle in reverse. Referring to FIG. 1 b , for example, in the EVT reverse mode, the clutch 50 is engaged, the generator 80 has a torque of −3.27 units, the motor 82 has a torque of −2.56 units, and an output torque of −8.33 is achieved, corresponding to an engine torque of 1 unit.
The third operating mode includes the “reverse and forward launch modes” (also referred to as “torque converter reverse and forward modes”) corresponding with the third and fourth rows (TC Rev and TC For) of each operating mode table, such as that of FIG. 1 b . In this mode, the EVT is driven by the engine and one of the motor/generators. A selectable fraction of the energy generated in the generator unit is stored in the battery, with the remaining energy being transferred to the motor. In FIG. 1 , this fraction is approximately 99%. The ratio of transmission output speed to engine speed (transmission speed ratio) is approximately +/−0.001 (the positive sign indicates that the vehicle is creeping forward and negative sign indicates that the vehicle is creeping backwards). Referring to FIG. 1 b , in the reverse and forward launch modes, the clutch 50 is engaged. In the TC Reverse mode, the motor/generator 80 acts as a generator with −2.85 units of torque, the motor/generator 82 acts as a motor with −2.15 units of torque, and a torque ratio of −7.00 is achieved. In the TC Forward mode, the motor/generator 80 acts as a motor with 0.79 units of torque, the motor/generator 82 acts as a generator with 1.44 units of torque, and a torque ratio of 4.69 is achieved.
The fourth operating mode is a “continuously variable transmission range mode” which includes the Range 1 . 1 , Range 1 . 2 , Range 1 . 3 , Range 1 . 4 , Range 2 . 1 , Range 2 . 2 , Range 2 . 3 and Range 2 . 4 operating points corresponding with rows 5 - 12 of each operating point table, such as that of FIG. 1 b . In this mode, the EVT is driven by the engine as well as one of the motor/generators operating as a motor. The other motor/generator operates as a generator and transfers 100% of the generated energy back to the motor. The operating points represented by Range 1 . 1 , 1 . 2 , . . . , etc. are discrete points in the continuum of forward speed ratios provided by the EVT. For example in FIG. 1 b , a range of torque ratios from 4.69 to 1.86 is achieved with the clutch 50 engaged, and a range of ratios 1.36 to 0.54 is achieved with the clutch 52 engaged.
The fifth operating mode includes the “fixed ratio” modes (F 1 , F 2 ) corresponding with rows 13 - 14 of each operating mode table (i.e. operating mode table), such as that of FIG. 1 b . In this mode the transmission operates like a conventional automatic transmission, with one or two torque transfer devices engaged to create a discrete transmission ratio. The clutching table accompanying each figure shows only one to three fixed-ratio forward speeds but additional fixed ratios may be available. Referring to FIG. 1 b , in fixed ratio F 1 the clutch 50 and brake 55 are engaged to achieve a fixed torque ratio of 2.15. Accordingly, each “X” in the column of motor/generator 82 in FIG. 1 b indicates that the brake 55 is engaged and the motor/generator 82 is not rotating. In fixed ratio F 2 , the clutches 52 and 55 are engaged to achieve a fixed ratio of 0.97.
The transmission 14 is capable of operating in so-called single or dual modes. In single mode, the engaged torque transfer device remains the same for the entire continuum of forward speed ratios (represented by the discrete points: Ranges 1 . 1 , 1 . 2 , 1 . 3 and 1 . 4 ). In dual mode, the engaged torque transfer device is switched at some intermediate speed ratio (e.g., Range 2 . 1 in FIG. 1 ). Depending on the mechanical configuration, this change in torque transfer device engagement has advantages in reducing element speeds in the transmission.
As set forth above, the engagement schedule for the torque transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 1 b . FIG. 1 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 1 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 20 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 30 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 40 . Also, the chart of FIG. 1 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 2.22, and the ratio spread is 2.22.
DESCRIPTION OF A SECOND EXEMPLARY EMBODIMENT
With reference to FIG. 2 a , a powertrain 110 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 114 . Transmission 114 is designed to receive at least a portion of its driving power from the engine 12 .
In the embodiment depicted the engine 12 may also be a fossil fuel engine, such as a diesel engine which is readily adapted to provide its available power output typically delivered at a constant number of revolutions per minute (RPM). As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 14 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 114 . An output member 19 of the transmission 114 is connected to a final drive 16 .
The transmission 114 utilizes three differential gear sets, preferably in the nature of planetary gear sets 120 , 130 and 140 . The planetary gear set 120 employs an outer gear member 124 , typically designated as the ring gear. The ring gear member 124 circumscribes an inner gear member 122 , typically designated as the sun gear. A carrier member 126 rotatably supports a plurality of planet gears 127 such that each planet gear 127 meshingly engages both the outer, ring gear member 124 and the inner, sun gear member 122 of the first planetary gear set 120 .
The planetary gear set 130 also has an outer gear member 134 , often also designated as the ring gear, that circumscribes an inner gear member 132 , also often designated as the sun gear. A plurality of planet gears 137 are also rotatably mounted in a carrier member 136 such that each planet gear member 137 simultaneously, and meshingly, engages both the outer, ring gear member 134 and the inner, sun gear member 132 of the planetary gear set 130 .
The planetary gear set 140 also has an outer gear member 144 , often also designated as the ring gear, that circumscribes an inner gear member 142 , also often designated as the sun gear. A plurality of planet gears 147 are also rotatably mounted in a carrier member 146 such that each planet gear member 147 simultaneously, and meshingly, engages both the outer, ring gear member 144 and the inner, sun gear member 142 of the planetary gear set 140 .
The transmission input member 17 is continuously connected with the ring gear member 124 of the planetary gear set 120 . The transmission output member 19 is connected with the carrier member 146 of the planetary gear set 140 . A first interconnecting member 170 continuously connects the carrier member 126 of the planetary gear set 120 with the carrier member 136 of the planetary gear set 130 . A second interconnecting member 172 continuously connects the sun gear member 122 of the planetary gear set 120 with the ring gear member 134 of the planetary gear set 130 . A third interconnecting member 174 continuously connects the ring gear member 134 of the planetary gear set 130 with the transmission housing 160 .
The transmission 114 also incorporates first and second motor/generators 180 and 182 , respectively. The stator of the first motor/generator 180 is secured to the transmission housing 160 . The rotor of the first motor/generator 180 is secured to the sun gear member 132 of the planetary gear set 130 .
The stator of the second motor/generator 182 is also secured to the transmission housing 160 . The rotor of the second motor/generator 182 is secured to the sun gear member 142 of the planetary gear set 140 .
A first torque transfer device, such as clutch 150 , selectively connects the carrier member 136 of the planetary gear set 130 with the ring gear member 144 of the planetary gear set 140 . A second torque transfer device, such as clutch 152 , selectively connects the ring gear member 124 of the planetary gear set 120 with the ring gear member 144 of the planetary gear set 140 . A third torque transfer device, such as brake 154 , selectively connects the carrier member 126 of the planetary gear set 120 with the transmission housing 160 . A fourth torque transfer device, such as the brake 155 , is connected in parallel with the motor/generator 182 for selectively braking rotation thereof. The first, second, third and fourth torque transfer devices 150 , 152 , 154 and 155 are employed to assist in the selection of the operational modes of the hybrid transmission 114 .
Returning now to the description of the power sources, it should be apparent from the foregoing description, and with particular reference to FIG. 2 a , that the transmission 114 selectively receives power from the engine 12 . The hybrid transmission also exchanges power with an electric power source 186 , which is operably connected to a controller 188 . The electric power source 186 may be one or more batteries. Other electric power sources, such as fuel cells, that have the ability to provide, or store, and dispense electric power may be used in place of batteries without altering the concepts of the present invention.
As described previously, each embodiment has thirteen to fifteen functional requirements (corresponding with the 13 to 15 rows of each operating mode table shown in the Figures) which may be grouped into five operating modes. The first operating mode is the “battery reverse mode” which corresponds with the first row (Batt Rev) of the operating mode table of FIG. 2 b . In this mode, the engine is off and the transmission element connected to the engine is effectively allowed to freewheel, subject to engine inertia torque. The EVT is driven by one of the motor/generators using energy from the battery, causing the vehicle to move in reverse. The other motor/generator may or may not rotate in this mode. As shown in FIG. 2 b , in this mode the clutch 150 and brake 154 are engaged, the motor 180 has zero torque, the generator 182 has a torque of −1.00 units and an output torque of −3.25 is achieved, by way of example.
The second operating mode is the “EVT reverse mode” (or mechanical reverse mode) which corresponds with the second row (EVT Rev) of the operating mode table of FIG. 2 b . In this mode, the EVT is driven by the engine and by one of the motor/generators. The other motor/generator operates in generator mode and transfers 100% of the generated energy back to the driving motor. The net effect is to drive the vehicle in reverse. In this mode, the clutch 150 is engaged, the generator 180 has a torque of −2.35 units, the motor 182 has a torque of −2.56 units, and an output torque of −8.33 is achieved, corresponding to an input torque of 1 unit.
The third operating mode includes the “reverse and forward launch modes” corresponding with the third and fourth rows (TC Rev and TC For) of each operating mode table, such as that of FIG. 2 b . In this mode, the EVT is driven by the engine and one of the motor/generators. A selectable fraction of the energy generated in the generator unit is stored in the battery, with the remaining energy being transferred to the motor. In TC Rev, the clutch 150 is engaged, the motor/generator 180 acts as a generator with −2.05 units of torque, the motor/generator 182 acts as a motor with −2.15 units of torque, and a torque ratio of −7.00 is achieved. In TC For, the clutch 150 is engaged, the motor/generator 180 acts as a motor with 0.57 units of torque, the motor/generator 182 acts as a generator with 1.44 units of torque, and a torque ratio of 4.69 is achieved. For these torque ratios, approximately 99% of the generator energy is stored in the battery.
The fourth operating mode includes the “Range 1 . 1 , Range 1 . 2 , Range 1 . 3 , Range 1 . 4 , Range 2 . 1 , Range 2 . 2 , Range 2 . 3 and Range 2 . 4 ” modes corresponding with rows 5 - 12 of the operating mode table of FIG. 2 b . In this mode, the EVT is driven by the engine as well as one of the motor/generators operating as a motor. The other motor/generator operates as a generator and transfers 100% of the generated energy back to the motor. The operating points represented by Range 1 . 1 , 1 . 2 . . . , etc. are discrete points in the continuum of forward speed ratios provided by the EVT. For example in FIG. 2 b , a range of ratios from 4.69 to 1.86 is achieved with the clutch 150 engaged, and a range of ratios from 1.36 to 0.54 is achieved with the clutch 152 engaged.
The fifth operating mode includes the fixed “ratio” modes (F 1 , F 2 ) corresponding with rows 13 - 14 of the operating mode table of FIG. 2 b . In this mode the transmission operates like a conventional automatic transmission, with two torque transfer devices engaged to create a discrete transmission ratio. In fixed ratio F 1 the clutch 150 and brake 155 are engaged to achieve a fixed ratio of 2.15. In fixed ratio F 2 , the clutch 152 and brake 155 are engaged to achieve a fixed ratio of 1.45.
As set forth above, the engagement schedule for the torque transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 2 b . FIG. 2 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 2 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 120 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 130 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 140 . Also, the chart of FIG. 2 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.48.
DESCRIPTION OF A THIRD EXEMPLARY EMBODIMENT
With reference to FIG. 3 a , a powertrain 210 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 214 . The transmission 214 is designed to receive at least a portion of its driving power from the engine 12 . As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 214 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission 214 .
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member is operatively connected to a planetary gear set in the transmission 214 . An output member 19 of the transmission 214 is connected to a final drive 16 .
The transmission 214 utilizes three differential gear sets, preferably in the nature of planetary gear sets 220 , 230 and 240 . The planetary gear set 220 employs an outer gear member 224 , typically designated as the ring gear. The ring gear member 224 circumscribes an inner gear member 222 , typically designated as the sun gear. A carrier member 226 rotatably supports a plurality of planet gears 227 such that each planet gear member 227 meshingly engages both the outer, ring gear member 224 and the inner, sun gear member 222 of the first planetary gear set 220 .
The planetary gear set 230 also has an outer ring gear member 234 that circumscribes an inner sun gear member 232 . A plurality of planet gears 237 are also rotatably mounted in a carrier member 236 such that each planet gear member 237 simultaneously, and meshingly, engages both the outer ring gear member 234 and the inner sun gear member 232 of the planetary gear set 230 .
The planetary gear set 240 also has an outer ring gear member 244 that circumscribes an inner sun gear member 242 . A plurality of planet gears 247 are rotatably mounted in a carrier member 246 such that each planet gear member 247 simultaneously and meshingly engages both the outer, ring gear member 244 and the inner, sun gear member 242 of the planetary gear set 240 .
The transmission input member 17 is connected with the ring gear member 224 . The transmission output member 19 is connected to the carrier member 246 . A first interconnecting member 270 continuously connects the sun gear member 222 with the carrier member 236 . A second interconnecting member 272 connects the carrier member 226 with the ring gear member 234 . A third interconnecting member 274 continuously connects the carrier member 236 with the transmission housing 260 .
The transmission 214 also incorporates first and second motor/generators 280 and 282 , respectively. The stator of the first motor/generator 280 is secured to the transmission housing 260 . The rotor of the first motor/generator 280 is secured to the sun gear member 232 . The stator of the second motor/generator 282 is also secured to the transmission housing 260 . The rotor of the second motor/generator 282 is secured to the sun gear member 242 .
A first torque-transfer device, such as clutch 250 , selectively connects the carrier member 226 with the ring gear member 244 . A second torque-transfer device, such as clutch 252 , selectively connects the ring gear member 224 with the ring gear member 244 . A third torque transfer device, such as brake 254 , selectively connects the carrier member 226 with the transmission housing 260 . A fourth torque transfer device, such as the brake 255 , is connected in parallel with the motor/generator 282 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 250 , 252 , 254 and 255 are employed to assist in the selection of the operational modes of the hybrid transmission 214 .
The hybrid transmission 214 receives power from the engine 12 , and also from electric power source 286 , which is operably connected to a controller 288 .
The operating mode table of FIG. 3 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 214 . These modes include the “battery reverse mode” (Batt Rev), “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “range 1 . 1 , 1 . 2 , 1 . 3 . . . modes” and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 3 b . FIG. 3 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 3 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 220 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 230 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 240 . Also, the chart of FIG. 3 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between the first and second fixed forward torque ratios is 1.48.
DESCRIPTION OF A FOURTH EXEMPLARY EMBODIMENT
With reference to FIG. 4 a , a powertrain 310 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 314 . The transmission 314 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 314 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 314 . An output member 19 of the transmission 314 is connected to a final drive 16 .
The transmission 314 utilizes three planetary gear sets 320 , 330 and 340 . The planetary gear set 320 employs an outer ring gear member 324 which circumscribes an inner sun gear member 322 . A carrier member 326 rotatably supports a plurality of planet gears 327 such that each planet gear 327 meshingly engages both the outer ring gear member 324 and the inner sun gear member 322 of the first planetary gear set 320 .
The planetary gear set 330 also has an outer ring gear member 334 that circumscribes an inner sun gear member 332 . A plurality of planet gears 337 are also rotatably mounted in a carrier member 336 such that each planet gear member 337 simultaneously, and meshingly engages both the outer, ring gear member 334 and the inner, sun gear member 332 of the planetary gear set 330 .
The planetary gear set 340 also has an outer ring gear member 344 that circumscribes an inner sun gear member 342 . A plurality of planet gears 347 are also rotatably mounted in a carrier member 346 such that each planet gear member 347 simultaneously, and meshingly, engages both the outer ring gear member 344 and the inner sun gear member 342 of the planetary gear set 340 .
The transmission input member 17 is connected with the ring gear member 324 . The transmission output member 19 is connected with the carrier member 346 . A first interconnecting member 370 continuously connects the carrier member 326 with carrier member 336 . A second interconnecting member 372 continuously connects the sun gear member 322 with the sun gear member 332 . A third interconnecting member 374 continuously connects the sun gear member 322 with the transmission housing 360 .
The transmission 314 also incorporates first and second motor/generators 380 and 382 , respectively. The stator of the first motor/generator 380 is secured to the transmission housing 360 . The rotor of the first motor/generator 380 is secured to the ring gear member 334 . The stator of the second motor/generator 382 is also secured to the transmission housing 360 . The rotor of the second motor/generator 382 is secured to the sun gear member 342 .
A first torque-transfer device, such as clutch 350 , selectively connects the carrier member 336 with the ring gear member 344 . A second torque-transfer device, such as clutch 352 , selectively connects the ring gear member 334 with the ring gear member 344 . A third torque transfer device, such as brake 354 , selectively connects the carrier member 326 with the transmission housing 360 . A fourth torque transfer device, such as the brake 355 , is connected in parallel with the motor/generator 382 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 350 , 352 , 354 and 355 are employed to assist in the selection of the operational modes of the transmission 314 .
The hybrid transmission 314 receives power from the engine 12 , and also exchanges power with an electric power source 386 , which is operably connected to a controller 388 .
The operating mode table of FIG. 4 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 314 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 4 b . FIG. 4 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 4 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 320 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 330 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 340 . Also, the chart of FIG. 4 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.48.
DESCRIPTION OF A FIFTH EXEMPLARY EMBODIMENT
With reference to FIG. 5 a , a powertrain 410 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 414 . The transmission 414 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 414 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 414 . An output member 19 of the transmission 414 is connected to a final drive 16 .
The transmission 414 utilizes three planetary gear sets 420 , 430 and 440 . The planetary gear set 420 employs an outer ring gear member 424 which circumscribes an inner sun gear member 422 . A carrier member 426 rotatably supports a plurality of planet gears 427 such that each planet gear 427 meshingly engages both the outer ring gear member 424 and the inner sun gear member 422 of the first planetary gear set 420 .
The planetary gear set 430 also has an outer ring gear member 434 that circumscribes an inner sun gear member 432 . A plurality of planet gears 437 are also rotatably mounted in a carrier member 436 such that each planet gear member 437 simultaneously, and meshingly engages both the outer, ring gear member 434 and the inner, sun gear member 432 of the planetary gear set 430 .
The planetary gear set 440 also has an outer ring gear member 444 that circumscribes an inner sun gear member 442 . A plurality of planet gears 447 are also rotatably mounted in a carrier member 446 such that each planet gear member 447 simultaneously, and meshingly, engages both the outer ring gear member 444 and the inner sun gear member 442 of the planetary gear set 440 .
The transmission input member 17 is continuously connected with the sun gear member 422 . The transmission output member 19 is continuously connected with the ring gear member 444 . A first interconnecting member 470 continuously connects the carrier member 426 with the carrier member 436 . A second interconnecting member 472 continuously connects the ring gear member 424 with the ring gear member 434 . A third interconnecting member 474 continuously connects the ring gear member 434 with the transmission housing 460 .
The transmission 414 also incorporates first and second motor/generators 480 and 482 , respectively. The stator of the first motor/generator 480 is secured to the transmission housing 460 . The rotor of the first motor/generator 480 is secured to the sun gear member 432 . The stator of the second motor/generator 482 is also secured to the transmission housing 460 . The rotor of the second motor/generator 482 is secured to the sun gear member 442 .
A first torque-transfer device, such as clutch 450 , selectively connects the carrier member 436 with the carrier member 446 . A second torque-transfer device, such as clutch 452 , selectively connects the sun gear member 422 with the carrier member 446 . A third torque transfer device, such as brake 454 , selectively connects the carrier member 426 with the transmission housing 460 . A fourth torque transfer device, such as the brake 455 , is connected in parallel with the motor/generator 482 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 450 , 452 , 454 and 455 are employed to assist in the selection of the operational modes of the transmission 414 .
The hybrid transmission 414 receives power from the engine 12 and also from an electric power source 486 , which is operably connected to a controller 488 .
The operating mode table of FIG. 5 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 414 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 5 b . FIG. 5 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 5 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 420 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 430 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 440 . Also, the chart of FIG. 5 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 3.10.
DESCRIPTION OF A SIXTH EXEMPLARY EMBODIMENT
With reference to FIG. 6 a , a powertrain 510 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 514 . The transmission 514 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 514 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 514 . An output member 19 of the transmission 514 is connected to a final drive 16 .
The transmission 514 utilizes three planetary gear sets 520 , 530 and 540 . The planetary gear set 520 employs an outer ring gear member 524 which circumscribes an inner sun gear member 522 . A carrier member 526 rotatably supports a plurality of planet gears 527 such that each planet gear 527 meshingly engages both the outer ring gear member 524 and the inner sun gear member 522 of the first planetary gear set 520 .
The planetary gear set 530 also has an outer ring gear member 534 that circumscribes an inner sun gear member 532 . A plurality of planet gears 537 are also rotatably mounted in a carrier member 536 such that each planet gear member 537 simultaneously, and meshingly engages both the outer, ring gear member 534 and the inner, sun gear member 532 of the planetary gear set 530 .
The planetary gear set 540 also has an outer ring gear member 544 that circumscribes an inner sun gear member 542 . A plurality of planet gears 547 are also rotatably mounted in a carrier member 546 such that each planet gear member 547 simultaneously, and meshingly engages both the inner, sun gear member 542 and the outer, ring gear member 544 of the planetary gear set 540 .
The transmission input member 17 is continuously connected with the carrier member 526 . The transmission output member 19 is continuously connected with the ring gear member 544 . The first interconnecting member 570 continuously connects the sun gear member 522 with the sun gear member 532 . A second interconnecting member 572 continuously connects the carrier member 526 with the ring gear member 534 . A third interconnecting member 574 continuously connects the sun gear member 522 with the transmission housing 560 .
The transmission 514 also incorporates first and second motor/generators 580 and 582 , respectively. The stator of the first motor/generator 580 is secured to the transmission housing 560 . The rotor of the first motor/generator 580 is secured to the ring gear member 524 . The stator of the second motor/generator 582 is also secured to the transmission housing 560 . The rotor of the second motor/generator 582 is secured to the sun gear member 542 .
A first torque-transfer device, such as clutch 550 , selectively connects the carrier member 536 with the carrier member 546 . A second torque-transfer device, such as clutch 552 , selectively connects the carrier member 536 with the ring gear member 544 . A third torque transfer device, such as the brake 554 , selectively connects the carrier member 546 with the transmission housing 560 . The first, second and third torque-transfer devices 550 , 552 and 554 are employed to assist in the selection of the operational modes of the hybrid transmission 514 .
The hybrid transmission 514 receives power from the engine 12 , and also exchanges power with an electric power source 586 , which is operably connected to a controller 588 .
The operating mode table of FIG. 6 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 514 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 6 b . FIG. 6 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 6 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 520 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 530 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 540 .
DESCRIPTION OF A SEVENTH EXEMPLARY EMBODIMENT
With reference to FIG. 7 a , a powertrain 610 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 614 . The transmission 614 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 614 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 614 . An output member 19 of the transmission 614 is connected to a final drive 16 .
The transmission 614 utilizes three planetary gear sets 620 , 630 and 640 . The planetary gear set 620 employs an outer ring gear member 624 which circumscribes an inner sun gear member 622 . A carrier member 626 rotatably supports a plurality of planet gears 627 such that each planet gear 627 meshingly engages both the outer ring gear member 624 and the inner sun gear member 622 of the first planetary gear set 620 .
The planetary gear set 630 also has an outer ring gear member 634 that circumscribes an inner sun gear member 632 . A plurality of planet gears 637 are also rotatably mounted in a carrier member 636 such that each planet gear member 637 simultaneously, and meshingly engages both the outer, ring gear member 634 and the inner, sun gear member 632 of the planetary gear set 630 .
The planetary gear set 640 also has an outer ring gear member 644 that circumscribes an inner sun gear member 642 . A plurality of planet gears 647 are also rotatably mounted in a carrier member 646 such that each planet gear member 647 simultaneously, and meshingly, engages both the outer ring gear member 644 and the inner sun gear member 642 of the planetary gear set 640 .
The transmission input member 17 is continuously connected with the carrier member 636 . The transmission output member 19 is connected with the carrier member 646 . A first interconnecting member 670 continuously connects the carrier member 626 with the carrier member 636 . A second interconnecting member 672 continuously connects the sun gear member 622 with the sun gear member 632 . A third interconnecting member 674 continuously connects the sun gear member 622 with the transmission housing 660 .
The transmission 614 also incorporates first and second motor/generators 680 and 682 , respectively. The stator of the first motor/generator 680 is secured to the transmission housing 660 . The rotor of the first motor/generator 680 is secured to the ring gear member 624 . The stator of the second motor/generator 682 is also secured to the transmission housing 660 . The rotor of the second motor/generator 682 is secured to the sun gear member 642 .
A first torque-transfer device, such as clutch 650 , selectively connects the carrier member 636 with the sun gear member 642 . A second torque transfer device, such as clutch 652 , selectively connects the ring gear member 634 with the ring gear member 644 . A third torque transfer device, such as brake 654 , selectively connects the ring gear member 644 with the transmission housing 660 . A fourth torque transfer device, such as the brake 655 , is connected in parallel with the motor/generator 682 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 650 , 652 , 654 and 655 are employed to assist in the selection of the operational modes of the transmission 614 .
The hybrid transmission 614 receives power from the engine 12 , and also exchanges power with an electric power source 686 , which is operably connected to a controller 688 .
The operating mode table of FIG. 7 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 614 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 , F 3 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 7 b . FIG. 7 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 7 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 620 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 630 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 640 . Also, the chart of FIG. 7 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 3.35, and the ratio spread is 4.33.
DESCRIPTION OF AN EIGHTH EXEMPLARY EMBODIMENT
With reference to FIG. 8 a , a powertrain 710 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 714 . The transmission 714 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 714 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 714 . An output member 19 of the transmission 714 is connected to a final drive 16 .
The transmission 714 utilizes three planetary gear sets 720 , 730 and 740 . The planetary gear set 720 employs an outer ring gear member 724 which circumscribes an inner sun gear member 722 . A carrier member 726 rotatably supports a plurality of planet gears 727 such that each planet gear 727 meshingly engages both the outer ring gear member 724 and the inner sun gear member 722 of the first planetary gear set 720 .
The planetary gear set 730 also has an outer ring gear member 734 that circumscribes an inner sun gear member 732 . A plurality of planet gears 737 are also rotatably mounted in a carrier member 736 such that each planet gear member 737 simultaneously, and meshingly engages both the outer, ring gear member 734 and the inner, sun gear member 732 of the planetary gear set 730 .
The planetary gear set 740 also has an outer ring gear member 744 that circumscribes an inner sun gear member 742 . A plurality of planet gears 747 are also rotatably mounted in a carrier member 746 such that each planet gear member 747 simultaneously, and meshingly, engages both the outer ring gear member 744 and the inner sun gear member 742 of the planetary gear set 740 .
The transmission input member 17 is continuously connected with the ring gear member 724 . The transmission output member 19 is continuously connected with the ring gear member 744 . A first interconnecting member 770 continuously connects the ring gear member 724 with ring gear member 734 . A second interconnecting member 772 continuously connects the sun gear member 722 with sun gear member 732 . A third interconnecting member 774 continuously connects the sun gear member 722 with the transmission housing 760 .
The transmission 714 also incorporates first and second motor/generators 780 and 782 , respectively. The stator of the first motor/generator 780 is secured to the transmission housing 760 . The rotor of the first motor/generator 780 is secured to the carrier member 726 . The stator of the second motor/generator 782 is also secured to the transmission housing 760 . The rotor of the second motor/generator 782 is secured to the sun gear member 742 .
A first torque-transfer device, such as clutch 750 , selectively connects the carrier member 736 with the carrier member 746 . A second torque transfer device, such as clutch 752 , selectively connects the carrier member 736 with the ring gear member 744 . A third torque transfer device, such as the brake 754 , selectively connects the carrier member 746 with the transmission housing 760 . A fourth torque transfer device, such as the brake 755 , is connected in parallel with the motor/generator 782 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 750 , 752 , 754 and 755 are employed to assist in the selection of the operational modes of the transmission 714 .
The hybrid transmission 714 receives power from the engine 12 and also from an electric power source 786 , which is operably connected to a controller 788 .
The operating mode table of FIG. 8 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 714 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 8 b . FIG. 8 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 8 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 720 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 730 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 740 . Also, the chart of FIG. 8 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.33.
DESCRIPTION OF A NINTH EXEMPLARY EMBODIMENT
With reference to FIG. 9 a , a powertrain 810 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 814 . The transmission 814 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 814 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 814 . An output member 19 of the transmission 814 is connected to a final drive 16 .
The transmission 814 utilizes three planetary gear sets 820 , 830 and 840 . The planetary gear set 820 employs an outer ring gear member 824 which circumscribes an inner sun gear member 822 . A plurality of planet gears 827 are also rotatably mounted in a carrier member 826 such that each planet gear member 827 simultaneously, and meshingly engages both the outer, ring gear member 824 and the inner, sun gear member 822 of the planetary gear set 820 .
The planetary gear set 830 also has an outer ring gear member 834 that circumscribes an inner sun gear member 832 . A plurality of planet gears 837 are also rotatably mounted in a carrier member 836 such that each planet gear member 837 simultaneously, and meshingly engages both the outer, ring gear member 834 and the inner, sun gear member 832 of the planetary gear set 830 .
The planetary gear set 840 also has an outer ring gear member 844 that circumscribes an inner sun gear member 842 . A plurality of planet gears 847 are also rotatably mounted in a carrier member 846 such that each planet gear member 847 simultaneously, and meshingly engages both the outer, ring gear member 844 and the inner, sun gear member 842 of the planetary gear set 840 .
The transmission input member 17 is continuously connected with the carrier member 836 . The transmission output member 19 is continuously connected with the ring gear member 844 . The first interconnecting member 870 continuously connects the sun gear member 822 with the sun gear member 832 . A second interconnecting member 872 continuously connects the ring gear member 824 with the carrier member 836 . A third interconnecting member 874 continuously connects the sun gear member 822 with the transmission housing 860 .
The transmission 814 also incorporates first and second motor/generators 880 and 882 , respectively. The stator of the first motor/generator 880 is secured to the transmission housing 860 . The rotor of the first motor/generator 880 is secured to the carrier member 826 . The stator of the second motor/generator 882 is also secured to the transmission housing 860 . The rotor of the second motor/generator 882 is secured to the sun gear member 842 .
A first torque-transfer device, such as clutch 850 , selectively connects the carrier member 826 with the carrier member 846 . A second torque-transfer device, such as clutch 852 , selectively connects the ring gear member 834 with the ring gear member 844 . A third torque transfer device, such as the brake 854 , selectively connects the carrier member 846 with the transmission housing 860 . A fourth torque-transfer device, such as the brake 855 , is connected in parallel with the motor/generator 882 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 850 , 852 , 854 and 855 are employed to assist in the selection of the operational modes of the hybrid transmission 814 .
The hybrid transmission 814 receives power from the engine 12 , and also exchanges power with an electric power source 886 , which is operably connected to a controller 888 .
The operating mode table of FIG. 9 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 814 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 9 b . FIG. 9 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 9 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 820 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 830 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 840 . Also, the chart of FIG. 9 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.67.
DESCRIPTION OF A TENTH EXEMPLARY EMBODIMENT
With reference to FIG. 10 a , a powertrain 910 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 914 . The transmission 914 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 914 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 914 . An output member 19 of the transmission 914 is connected to a final drive 16 .
The transmission 914 utilizes three planetary gear sets 920 , 930 and 940 . The planetary gear set 920 employs an outer ring gear member 924 which circumscribes an inner sun gear member 922 . A carrier member 926 rotatably supports a plurality of planet gears 927 , 928 . Each planet gear member 927 meshingly engages the outer ring gear member 924 and each planet gear member 928 simultaneously and meshingly engages both the inner sun gear member 922 and the respective planet gear 927 of the first planetary gear set 920 .
The planetary gear set 930 also has an outer ring gear member 934 that circumscribes an inner sun gear member 932 . A plurality of planet gears 937 are also rotatably mounted in a carrier member 936 such that each planet gear member 937 simultaneously, and meshingly engages both the outer, ring gear member 934 and the inner, sun gear member 932 of the planetary gear set 930 .
The planetary gear set 940 also has an outer ring gear member 944 that circumscribes an inner sun gear member 942 . A plurality of planet gears 947 are also rotatably mounted in a carrier member 946 such that each planet gear member 947 simultaneously, and meshingly engages both the outer, ring gear member 944 and the inner, sun gear member 942 of the planetary gear set 940 .
The transmission input member 17 is continuously connected with the carrier member 936 . The transmission output member 19 is continuously connected with the carrier member 946 . The first interconnecting member 970 continuously connects the sun gear member 922 with the sun gear member 932 . A second interconnecting member 972 continuously connects the carrier member 926 with the carrier member 936 . A third interconnecting member 974 continuously connects the sun gear member 922 with the transmission housing 960 .
The transmission 914 also incorporates first and second motor/generators 980 and 982 , respectively. The stator of the first motor/generator 980 is secured to the transmission housing 960 . The rotor of the first motor/generator 980 is secured to the ring gear member 934 . The stator of the second motor/generator 982 is also secured to the transmission housing 960 . The rotor of the second motor/generator 982 is secured to the sun gear member 942 .
A first torque-transfer device, such as clutch 950 , selectively connects the ring gear member 924 with the ring gear member 944 . A second torque-transfer device, such as clutch 952 , selectively connects the ring gear member 934 with the ring gear member 944 . A third torque transfer device, such as the brake 954 , selectively connects the ring gear member 924 with the transmission housing 960 . A fourth torque transfer device, such as the brake 955 , is connected in parallel with the motor/generator 982 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 950 , 952 , 954 and 955 are employed to assist in the selection of the operational modes of the hybrid transmission 914 .
The hybrid transmission 914 receives power from the engine 12 , and also exchanges power with an electric power source 986 , which is operably connected to a controller 988 .
The operating mode table of FIG. 10 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 914 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 10 b . FIG. 10 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 10 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 920 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 930 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 940 . Also, the chart of FIG. 10 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 2.22.
DESCRIPTION OF AN ELEVENTH EXEMPLARY EMBODIMENT
With reference to FIG. 11 a , a powertrain 1010 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 1014 . The transmission 1014 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 1014 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 1014 . An output member 19 of the transmission 1014 is connected to a final drive 16 .
The transmission 1014 utilizes three planetary gear sets 1020 , 1030 and 1040 . The planetary gear set 1020 employs an outer ring gear member 1024 which circumscribes an inner sun gear member 1022 . A carrier member 1026 rotatably supports a plurality of planet gears 1027 such that each planet gear member 1027 meshingly engages both the outer ring gear member 1024 and the inner sun gear member 1022 of the first planetary gear set 1020 .
The planetary gear set 1030 has an inner sun gear member 1032 . A carrier member 1036 rotatably supports a plurality of planet gears 1037 , 1038 . The planet gears 1037 meshingly engage the inner sun gear member 1032 and the respective planet gears 1038 . The planet gears 1038 are integral with the planet gears 1027 (i.e., they are formed by long pinion gears).
The planetary gear set 1040 also has an outer ring gear member 1044 that circumscribes an inner sun gear member 1042 . A carrier member 1046 rotatably supports a plurality of planet gears 1047 such that each planet gear member 1047 meshingly engages both the outer ring gear member 1044 and the inner sun gear member 1042 of the planetary gear set 1040 .
The transmission input member 17 is continuously connected with the ring gear member 1024 . The transmission output member 19 is continuously connected with the carrier member 1046 . The carrier member 1026 is continuously connected with (i.e., integral with) the carrier member 1036 . This integral connection is referred to herein as the interconnecting member 1070 . The integral connection of the long pinion gears 1027 and 1038 is referred to herein as the second interconnecting member 1072 . A third interconnecting member 1074 continuously connects the sun gear member 1022 with the transmission housing 1060 .
The transmission 1014 also incorporates first and second motor/generators 1080 and 1082 , respectively. The stator of the first motor/generator 1080 is secured to the transmission housing 1060 . The rotor of the first motor/generator 1080 is secured to the sun gear member 1032 . The stator of the second motor/generator 1082 is also secured to the transmission housing 1060 . The rotor of the second motor/generator 1082 is secured to the sun gear member 1042 .
A first torque-transfer device, such as clutch 1050 , selectively connects the carrier member 1026 with the ring gear member 1044 . A second torque-transfer device, such as clutch 1052 , selectively connects the ring gear member 1024 with the ring gear member 1044 . A third torque transfer device, such as brake 1054 , selectively connects the carrier member 1036 with the transmission housing 1060 . A fourth torque transfer device, such as the brake 1055 , is connected in parallel with the motor/generator 1082 for selectively braking rotation thereof. The first, second, third and fourth torque-transfer devices 1050 , 1052 , 1054 and 1055 are employed to assist in the selection of the operational modes of the hybrid transmission 1014 .
The hybrid transmission 1014 receives power from the engine 12 , and also exchanges power with an electric power source 1086 , which is operably connected to a controller 1088 .
The operating mode table of FIG. 11 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 1014 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 11 b . FIG. 11 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 11 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 1020 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 1030 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 1040 . Also, the chart of FIG. 11 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.48.
DESCRIPTION OF A TWELFTH EXEMPLARY EMBODIMENT
With reference to FIG. 12 a , a powertrain 1110 is shown, including an engine 12 connected to another embodiment of the improved electrically variable transmission, designated generally by the numeral 1114 . The transmission 1114 is designed to receive at least a portion of its driving power from the engine 12 .
As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 1114 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 1114 . An output member 19 of the transmission 1114 is connected to a final drive 16 .
The transmission 1114 utilizes three planetary gear sets 1120 , 1130 and 1140 . The planetary gear set 1120 has an outer ring gear member 1124 that circumscribes an inner sun gear member 1122 . A plurality of planet gears 1127 are rotatably mounted in a carrier member 1126 such that each planet gear member 1127 simultaneously, and meshingly engages both the outer, ring gear member 1124 and the inner, sun gear member 1122 of the planetary gear set 1120 .
The planetary gear set 1130 also has an outer ring gear member 1134 that circumscribes an inner sun gear member 1132 . A plurality of planet gears 1137 are also rotatably mounted in a carrier member 1136 such that each planet gear member 1137 simultaneously, and meshingly engages both the outer, ring gear member 1134 and the inner, sun gear member 1132 of the planetary gear set 1130 .
The planetary gear set 1140 also has an outer ring gear member 1144 that circumscribes an inner sun gear member 1142 . A plurality of planet gears 1147 are also rotatably mounted in a carrier member 1146 such that each planet gear member 1147 simultaneously, and meshingly engages both the outer, ring gear member 1144 and the inner, sun gear member 1142 of the planetary gear set 1140 .
The transmission input member 17 is continuously connected with the sun gear member 1142 . The transmission output member 19 is continuously connected with the carrier member 1126 . A first interconnecting member 1170 continuously connects the carrier member 1126 with the sun gear member 1132 . A second interconnecting member 1172 continuously connects the sun gear member 1122 with the ring gear member 1134 . A third interconnecting member 1174 continuously connects the ring gear member 1134 with the transmission housing 1160 .
The transmission 1114 also incorporates first and second motor/generators 1180 and 1182 , respectively. The stator of the first motor/generator 1180 is secured to the transmission housing 1160 . The rotor of the first motor/generator 1180 is selectively connectable with the ring gear member 1124 or the sun gear member 1142 via dog clutch 1192 . The stator of the second motor/generator 1182 is also secured to the transmission housing 1160 . The rotor of the second motor/generator 1182 is secured to the ring gear member 1144 .
A first torque-transfer device, such as clutch 1150 , selectively connects the ring gear member 1124 with the sun gear member 1142 . A second torque transfer device, such as clutch 1152 , selectively connects the carrier member 1136 with the carrier member 1146 . A third torque transfer device, such as the brake 1155 , is connected in parallel with the motor/generator 1182 for selectively braking rotation thereof. The first, second and third torque-transfer devices 1150 , 1152 and 1155 along with the dog clutch 1192 are employed to assist in the selection of the operational modes of the hybrid transmission 1114 .
The hybrid transmission 1114 receives power from the engine 12 , and also exchanges power with an electric power source 1186 , which is operably connected to a controller 1188 .
The operating mode table of FIG. 12 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 1114 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 ) as described previously.
As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 12 b . FIG. 12 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 12 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 1120 ; the N R2 /N S2 value is the tooth ratio of the planetary gear set 1130 ; and the N R3 /N S3 value is the tooth ratio of the planetary gear set 1140 . Also, the chart of FIG. 12 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.49.
In the claims, the language “continuously connected” or “continuously connecting” refers to a direct connection or a proportionally geared connection, such as gearing to an offset axis. Also, the “stationary member” or “ground” may include the transmission housing (case) or any other non-rotating component or components. Also, when a torque transfer mechanism is said to connect something to a member of a gear set, it may also be connected to an interconnecting member which connects it with that member. It is further understood that different features from different embodiments of the invention may be combined within the scope of the appended claims.
While various preferred embodiments of the present invention are disclosed, it is to be understood that the concepts of the present invention are susceptible to numerous changes apparent to one skilled in the art. Therefore, the scope of the present invention is not to be limited to the details shown and described but is intended to include all variations and modifications which come within the scope of the appended claims.
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The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first, second and third differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, three or four selectable torque-transfer devices, and possibly a dog clutch. The selectable torque transfer devices are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and mechanically fixed forward speed ratios. The torque transfer devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.
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TECHNICAL FIELD
This invention relates to hooks and more particularly to hooks that may hold more than one article
BACKGROUND OF THE INVENTION
There are many ways to hold more than one article from a wall. For instance, there are robe holders that have a single corbel having two hooks that rotate about separate axes disposed vertically in the corbel. Additionally some corbels have many hooks extending therefrom that do not move relative to each other. Some hooks are disposed coaxially but move separately from each and do not intersect.
SUMMARY OF THE INVENTION
According to an exemplar provided herein, a hinge hook has a pair of rotatable hooks that are mounted coaxially and side-by-side that move independently of each other.
According to an aspect of the exemplar stated above, each of the pair of hooks are mirror images of each other.
According to a further exemplar provided herein, a hinge hook has a first hook that is rotatable about an axis, and a second hook that is rotatable the same axis wherein upon rotation the first hook and the second hook come into contact with each other.
According to an exemplar provided herein a method for hanging articles includes providing a hinge hook having a pair of hooks mounted coaxially side-by-side and rotatable independently of each other, rotating the pair of hooks so that the pair of hooks are in contact side-by-side, and hanging a load from both of the hooks.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a hinge hook that as disclosed herein.
FIG. 2 shows an exploded view of the hinge hook of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, a hinge hook 10 has a left side hook 15 , a right side hook 20 , a base 25 , a hinge pin 30 and a pair of screws 35 .
The left side hook 15 has a first J-shape 40 for hanging more than one article (not shown) therefrom such as clothing (not shown) and a first pair of eyelets 45 (e.g., connector) for receiving the hinge pin 30 .
The right side hook 20 , similarly, also has a second J-shape 50 that mirrors the first J-shape 40 of the left side hook 15 , also for hanging more than one article therefrom. The right side hook 20 has a central eyelet 55 for receiving the hinge pin 30 . The central eyelet 55 of the right side hook 20 fits coaxially between the first pair of eyelets 45 of the left side hook 15 and is secured therein by the hinge pin 30 as will be discussed hereinbelow. Each of the first pair of eyelets 45 and the central eyelet 55 has a given diameter D for receiving the hinge pin 30 . Other shapes that mirror each other are contemplated herein. Each eyelet defined herein need not extend 360° about the hinge pin but may extend as many degrees as are necessary to secure the eyelet to the hinge pin 30 .
The base 25 has a second pair of eyelets 60 extending therefrom to receive the first pair eyelets 45 and the central eyelet 55 therebetween. The base 25 also has a pair of openings 65 through which screws 35 extend to attach the base to a wall or a door or an armoire or the like. Each of the second pair of eyelets also have a diameter D for receiving the hinge pin 30 therethrough except that one of the second pair of eyelets 60 has an interior threaded portion 70 .
The hinge pin 30 is cylindrical and has an exterior threaded portion 75 that mates with the interior threaded portion 70 of the second pair of eyelets 60 . One of ordinary skill in the art will recognize that the bottom or the top of the second pair of eyelets 60 may have the interior threaded portion 70 . However for aesthetic reasons, the bottom of the second pair of eyelets may be threaded so a screw indentation 80 (e.g., as for a flat head or Phillips screw driver) in the hinge pin 30 is not seen from above.
To construct and install the hinge hook 10 , the central eyelet 55 of the right hook 20 is placed between the first pair of the eyelets 45 in the left hook 15 . The central eyelet 55 of the right hook 20 and the first pair of the eyelets 45 in the left hook 15 are disposed between the second pair of eyelets 60 . The hinge pin 30 is extended through all the eyelets and anchored to the bottom of the second pair of eyelets 60 by screwing the exterior threaded portion 75 of the hinge pin 30 into the interior threaded portion of the base 25 to anchor the left side hook 15 and the right side hook 20 into place in the base 25 . The hinge pin 10 is assembled and then may be attached to the wall (not shown) or other surface where it may be desired by driving the screws 35 through the openings 65 into the wall (not shown) or the like. While the hinge pin here is shown with symmetrical sides one of ordinary skill will notice that the sides need not be symmetrical or could be of different shapes. The base 25 may be attached to a wall (not shown) or the like before the eyelets are attached thereto.
The right side hook 20 and the left side hook 15 may then rotate about the hinge pin 30 that defines a central axis but each of the left side hook 15 and the right side 20 hook may come into contact with the other of the left side hook 15 and the right side hook 20 . Moreover, because the left side hook 15 and the right side hook 20 are mirror images or have portions that are mirror images of each other, if they move together, they may be ganged to hold heavier article if one of the left side hook 15 or the right side hook 20 may not be able support a heavier article or articles.
Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.
The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims.
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A hinge hook has a pair of rotatable hooks that are mounted coaxially and side-by-side that move independently of each other.
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CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. application Ser. No. 13/776,463, filed Feb. 25, 2013 (now U.S. Pat. No. 8,867,798), which is a continuation of U.S. application Ser. No. 13/090,026, filed Apr. 19, 2011 (now U.S. Pat. No. 8,385,691), which is a continuation of U.S. application Ser. No. 12/874,929, filed Sep. 2, 2010 (now U.S. Pat. No. 7,929,810), which is a continuation of U.S. application Ser. No. 12/325,589, filed Dec. 1, 2008 (now U.S. Pat. No. 7,844,141), which is a continuation of U.S. application Ser. No. 11/056,699, filed Feb. 10, 2005 (now U.S. Pat. No. 7,460,737), which claims priority to U.S. Provisional Appl. No. 60/544,570, filed Feb. 12, 2004; the disclosures of each of the above-referenced applications are incorporated by reference herein in their entireties.
BACKGROUND OF THE INVENTION
Field of the Invention
Photography has transformed how people conceive of the world. Photographs allow people to see all sorts of things that are actually many miles away and/or years preceding. Photography lets people capture moments in time and preserve them for years to come.
Often people at a public place notice that a stranger has taken a photograph of which they would love to have a copy, Alternatively, after going somewhere, a person may bemoan the fact that he did not have a photograph of the event (in the present context, photograph also includes video, audio, or other representation).
A need exists, therefore, to provide a method and apparatus for identifying and connecting people with photographs they want. In addition, there is a need to provide a method and apparatus for characterizing errant photographs stored on computer databases that makes use of a variety of attributes to reliably characterize photographs in such a way as to reduce the amount of manual review necessary to identify and connect people with the photographs they want.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus that matches people with photographs in which they accidentally (or purposely) appear or with photographs of events they have attended.
Specifically, in one embodiment, a web site is created with a database backend. The database is seeded with information provided by (1) the photographer; (2) recovering metadata from the photograph; (3) reading devices such as a Global Positioning System (GPS) device; (4) referencing the account data of the photographer (i.e., account number, photographer's zip code or area code, etc.); (5) analyzing the photograph (i.e., computer recognizes eye color, optical character recognizes any text found in the photograph, recognizes the number of persons, the gender of persons, the hair color, the time of day by optical character recognizing any clocks in the photograph or analyzing the lighting conditions, the weather, etc.); (6) photograph quality information; and/or (7) any other information.
A user looking for a photograph would visit the web site and search for certain criteria. The user is then provided with a gallery of thumbnails that match the criteria. When the user identifies a photograph he wants to own, he can then download the full quality version, or order print(s). In a preferred implementation, the user is charged some amount of money that is split between the site owner and the photographer. Alternatively, the user may be charged in some other way, such as by viewing advertisements or by exchanging credits for downloads or by some other payment or a combination thereof.
A more complete understanding of the present invention will be afforded to those skilled in the art, as well as a realization of additional advantages and objects thereof, by a consideration of the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram showing exemplary steps of a method according to the invention.
FIG. 2 is a diagram showing an exemplary distinctive marker for photographic data.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention provides a method and apparatus that matches people with photographs in which they accidentally (or purposely) appear or with photographs of events they have attended.
FIG. 1 illustrates exemplary steps of a method 100 according to the invention. At optional step 102 , distinctive markers may be distributed to persons desiring to contribute photographic images to a database. The markers may comprise, for example, distinctive bins, badges, or stickers for placing on objects to be photographed. The markers should be designed so as to be easily recognized using automatic recognition algorithms, but should not be too conspicuous.
At step 104 , image data is collected from a variety of sources. It may be desirable to accept material from as many sources as possible, to increase the number of images available for browsing. Optionally, images may be accepted from qualified sources only.
At step 104 , source information regarding each photograph is collected. For example, at step 108 , the image provider may be asked for information, such as the time and date of the photograph, the subject matter, location, photographer, etc. Image metadata may also be read to obtain such information. Other ways of associating images to identifying information may include, for example, reading devices such as a Global Positioning System (GPS) device attached to a camera or other image capture device, or by referencing account data of the image contributor (e.g., account number, photographer's zip code or area code, etc.).
At step 110 , image data is analyzed to identify any characteristics that may be of interest to users. Such characteristics may include, for example, eye color, words and sentences, a number or gender of persons, the hair color, time of day, lighting conditions, and so forth. For further example, at step 112 , a facial recognition program as known in the art may be used to analyze any faces appearing in the photos at a sufficiently high resolution. At step 114 , the images may be analyzed for the presence of any known markers. And at step 116 , other features and qualities of the image may be classified, for example, whether it is taken indoors or outdoors, whether it contains people, dogs, cats, or other animals, whether it contains automobiles, airplanes, or other objects, and so forth. At step 118 , selected feature information and other source information is associated with each image and provided to any suitable relational database.
At step 120 , requests specifying search criteria for photographic images are received. For example, a user looking for a photograph may visit a web site hosted by the system and fill out a search form specifying search criteria of interest. The criteria may include specific subject matter, times, dates, and locations. For example, “Disneyland AND Matterhorn AND blue eye AND child AND Jan. 1, 2004 AND morning” would search for a photograph or photographs taken at Disneyland's Matterhorn with a child who has blue eyes on the morning of Jan. 1, 2004.
At step 122 , the image database is queried as known in the art, to identify images that at least partially match the search criteria. Such images may be presented, at step 124 , to the user. For example, the user may be provided with a gallery of “thumbnail” (reduced-size) images generated from images that match the criteria. When the user identifies a photograph he wants to own, he can then download the full quality version, or order print(s). In a preferred implementation, the user is charged some amount of money that is split between the site owner and the photographer. Alternatively, the user may be charged in some other ways such as by viewing advertisements or by exchanging credits for downloads or by some other payment or a combination thereof. The price can be on a sliding scale depending on the quality of the photograph that the user downloads or the size or quality of the print. For example, a photograph may cost $1.00 for 1024×768 resolution or $2.00 for 1600×1200 resolution. Similarly, a print may cost $1.00 for 3×5 or $5 for 8×10. For downloads, an “upgrade” may be possible by charging the difference between the resolutions. An automated process may be used to reduce the number of pixels for purposes of having a lower quality version to sell.
In addition, a surcharge may be applied (even if no surcharge is required) for various enhancements to the photograph, such as “upconverting” to a higher resolution, eliminating red-eye, enhancing shadow, color, or brightness, etc.
Moreover, when a photographer takes photographs, he can be provided with printed cards bearing a Uniform Resource Locator (URL) and a unique code in order that the user would be able to enter into the web site to find the photograph or the series of photographs then being taken. The photographer can also distribute cards (the printed cards bearing the URL and the unique code or any other cards known to those skilled in the art) to people whom he photographs, whether intentionally or inadvertently. The photographer can further advertise the same (e.g., the URL and the unique code) via a mark on his camera, a T-shirt, or other means.
Fixed-place cameras can also serve this function (e.g., the of photographer). For example, a camera set up at an intersection in Hollywood might take and upload one photograph every 10 seconds.
Photographers can also be given accounts and be allowed to upload photographs to the site. The database is populated during this process, although additional database information can be added later by web site users. In addition, the number of times the photograph has been purchased and/or viewed can be a part of the database.
In one embodiment, the method and apparatus of the present invention should be capable of face recognition. It should assign values to various factors (i.e., ratio of distance between pupils to distance to tip of nose, etc.). It would add this information to the database for uploaded photographs. A user can then upload a photograph of the target person and the system would then generate the same data from that photograph and use it to limit the possible search targets.
A provider of the present method and apparatus or a photographer can also hand out pins, clothing, or other materials that are marked in a way that allows a computer to later recognize them in a photograph. FIG. 2 shows an exemplary distinctive marker 200 having an optical code 202 , such as a bar code. The marker may have a color combination, distinctive shape, lettering, bar code, or other optical pattern, or some combination of the foregoing, that is unique to the marker. The marker may be computer generated, for example, and produced using an end-user's laser or ink-jet printer. The marker may be associated with specific information, for example, a particular user account, photographer, subject matter type, person, event, or location. Users can later search for photographs containing an image of the marker.
Numerous distribution mechanisms exist whereby photographs may be distributed from a source over a wide area network, such as the Internet. In some cases, the photographs are distributed using a centralized server system (such as Napster 2.0, eBay, or from a web site). In other cases, the photographs are distributed using a decentralized system (such as Gnutella). In a preferred implementation, the photographs are distributed to a person using the centralized server system or using a central hub.
Embodiments of the present invention operate in accordance with at least one web-hosting mechanism and a plurality of user mechanisms communicating over a wide area network, such as the Internet. Specifically, a web-hosting mechanism includes a database, an interface application and a server, wherein the server is adapted to communicate with a plurality of user mechanisms over a wide area network. It should be appreciated that the mechanisms described can include, but are not limited to, personal computers, mainframe computers, personal digital assistances, wireless communication devices and all other physical and wireless connected network devices generally known to those skilled in the art. It should further be understood that the database depicted can include, but is not limited, to RAM, cache memory, flash memory, magnetic disks, optical disks, removable disks, SCSI disks, IDE hard drives, tape drives, and all other types of data storage devices (and combinations thereof, such as RAID devices) generally known to those skilled in the art. In addition, the mechanisms described above are for purposes of example only and the invention is not limited thereby.
Having thus described several embodiments for photograph finding, it should be apparent to those skilled in the art that certain advantages of the system have been achieved. It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, in the context of the present invention a photograph can include video, audio, and/or other representation of how people conceive of the world. The invention is defined by the following claims.
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Digital image data including discrete photographic images of a variety of different subjects, times, and so forth, are collected and analyzed to identify specific features in the photographs. In an embodiment of the invention, distinctive markers are distributed to aid in the identification of particular subject matter. Facial recognition may also be employed. The digital image data is maintained in a database and quarried in response to search requests. The search requests include criteria specifying any feature category or other identifying information, such as date, time, and location that each photograph was taken, associated with each photograph. Candidate images are provided for review by requesters, who may select desired images for purchase or downloading.
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TECHNICAL FIELD
[0001] The present invention is generally related to magnetically enhanced reactive ion etching equipment, and more particularly to the calibration of the magnetic field of such equipment.
BACKGROUND OF THE INVENTION
[0002] Reactive ion etchers are used extensively by the microelectronics industry in the manufacturing of semiconductor and silicon based devices. Such devices include, for example, integrated circuits and micro-machined devices. Reactive ion etching is a dry etching process by which undesirable portions of a layer or film of one particular material are removed from a substrate wafer or layer of another material by chemical and/or physical interaction with a plasma etchant. For example, reactive ion etching may be used in conjunction with a mask layer to remove material in one or more layers beneath the mask layer in accordance with a pattern defined by the mask layer. In other words, certain etchants react with and remove the material in the layer or layers beneath the mask layer which are exposed to the etchant. The mask layer is substantially immune to the etchant's effects and remains in place. Additionally, reactive ion etchers are used to remove mask layers while leaving substantially undisturbed the layers below the mask including those portions that may be exposed to the etchant by virtue of the pattern established in the mask layer. Of course, the selection of the etchant, among other factors, will determine the chemical and/or physical reactivity or neutrality of the reactant's effect upon the various layers and mask utilized in any particular process.
[0003] Magnetically enchanced reactive ion etchers expose a wafer to a reactive plasma contained within a chamber which is additionally subjected to a controlled magnetic field conventionally provided by electromagnets. As used herein, magnetically enhanced reactive ion etchers include any of a variety of plasma based etchers wherein a controlled magnetic field, also referred to as a B-field, is impressed upon the plasma to control various plasma characteristics such as temperature, plasma uniformity and ion-bombardment energy. Process optimization therefore requires a repeatable, controllable B-field.
[0004] In FIG. 1 a typical reactive ion etching apparatus 100 is illustrated. Such an apparatus includes central plasma chamber 2 and a plurality of magnetic drive coils 10 a, 10 b, 12 a and 12 b symmetrically surrounding the chamber 2 . Each coil is oriented orthogonally with respect to the two immediately adjacent coils such that the magnetic field passing through the center of each coil is substantially orthogonal to the magnetic field passing through the center of each immediately adjacent coil. Opposing coil pairs are established by the two sets of on-adjacent coils 10 a, 10 b and 12 a, 12 b. Wafers are passed into the chamber through the center of coil 12 b and valve slit 6 .
[0005] Turning to FIG. 2, an exemplary sectional view taken through opposing coil pair 11 a, 11 b is illustrated. The magnetically enhanced reactive ion etching apparatus 200 in this figure is illustrated without a chamber lid in place, which would be conventional when service maintenance such as wet cleaning, kit changes or magnetic calibration is being performed. Illustration of a conventional lid assembly 60 is shown in FIG. 3. In the present illustration, access to chamber liner 31 through the lid opening 32 at the top of the apparatus 200 is required for magnetic probe tool 50 conventionally utilized in taking magnetic field measurements during chamber calibration.
[0006] Chamber walls 30 which are manufactured from a non-magnetic material such as aluminum generally define the plasma chamber liner 31 . Within the chamber is cathode 20 , which during process operation is subjected to an RF signal by generator 41 . Electrostatic chuck 22 is attached to cathode 20 and is employed for holding a semiconductor wafer in a reaction plasma chamber with a high level of accuracy during semiconductor processing.
[0007] Calibration tool 40 comprises a base portion 44 defining a locating feature 46 for accepting magnetic probe tool 50 including element 52 . Element 52 may for example be a hall device. Calibration tool 40 also includes standoff legs 42 which locate the tool to electrostatic chuck 22 at the desired height and orientation. With tool 40 properly located, a controlled location for probe tool 50 is established and the measurements of the magnetic fields generated by the coils will be repeatable.
[0008] Calibration of the apparatus 200 requires accurate measurements by the magnetic probe 50 of the magnetic field generated by each coil. Calibration of the coils may be required for example upon process changes requiring kit swapping or for such reasons as replacement of a coil driver or loss of data due to controller hard disk failures. In the former scenario, it is generally conventional practice to open the chamber and perform a variety of maintenance operations prior to releasing the apparatus for production use in the manufacturing environment. This includes venting of the chamber, removal of the chamber lid, gas distribution plate and all process kits. A wet cleaning of the chamber, lid and gas distribution plate as well as other ancillary maintenance operations are performed. This maintenance can take significant time and manpower resources. Eight to twelve hours of apparatus down time is common. In the latter scenarios, the same maintenance operations must be performed in conjunction with the conventional invasive calibration method. It is, however, generally desirable to avoid such otherwise unnecessary process steps.
[0009] As mentioned, calibration of the chamber magnetic field requires measurement of the magnetic field. This is accomplished by providing each coil in turn with a known DC drive voltage or current and taking a measurement of the magnetic field by the probe 50 via line 53 . The known voltage or current can be applied to the coils manually by way of controlled voltage or current sources or automatically through coil drivers 70 , 71 which control the voltage or current to coils 11 a and 11 b, respectively. Each coil driver 70 , 71 respond to external input signals 72 , 73 , respectively, such as a commanded voltage or current level from a process controller (not shown). The process controller may take many forms, for example a dedicated microprocessor based process controller with operator interface allowing voltage and current level selections during a calibration routine, or a general purpose PC based process controller with conventional keyboard/mouse operator interfaces also providing for voltage and current level selections during a calibration routine. Data corresponding to the generated magnetic field vector is collected for each coil. If a manual process is followed, data may be read by an operator from a data acquisition display of a device interfaced with the probe 50 . The manually read data is input to the process controller such as may be requested during a calibration routine executed by the controller. The process controller may also be adapted to automate the calibration process through data acquisition circuitry for monitoring and processing the signal from probe 50 element 52 during the calibration process via line 53 .
[0010] It may be desirable to take readings of the magnetic field of each coil for both phases of coil excitation. That is to say one reading at a positive DC voltage and current and one reading at a negative DC voltage and current. An average of the absolute value of the two readings or an aggregate of the absolute value of the two readings may then be used in the further steps of the calibration process. Also, multiple readings for each coil taken at different voltage or current magnitudes may be taken depending upon the granularity of the calibration method employed by the process controller. In summary, magnetic field measurements would be taken in accordance with the methodology set forth by the process equipment manufacturer.
[0011] The magnetic field measurements provide information regarding the absolute and relative performance of each coil of the process apparatus. Measurements of any one coil that is substantially different from an expected reading may be evidence of a faulty coil or coil driver. Expected values for the magnetic field readings are generally provided by the manufacturer of the plasma etching apparatus and are accurate for a given orientation of the magnetic probe such as is established with the calibration tool previously described. Assuming the magnetic field measurements for the coils fall within acceptable ranges, the process controller utilizes the data to normalize the response of the system to a desired response. This may be accomplished for example by applying a function, weight, adjustment factor or other trimming function to a base input signal of the respective coil drivers. Generally it is desirable to normalize the magnetic field of each coil such that equivalent independent fields would be generated. The precise method of calibration is not critical to the invention but it suffices to say that the drive voltage or current of each coil drive would be commanded in accordance with the desired system response by virtue of the calibration.
SUMMARY OF THE INVENTION
[0012] Therefore, it is one object of the invention to provide a non-invasive method of calibrating the magnetic field of a plasma chamber.
[0013] It is a further object to provide a non-invasive method of determining the magnetic field within a plasma chamber.
[0014] In accordance with the present invention, a reactive ion etcher is provided having a plasma chamber surrounded by magnetic coils. Through a series of measurements of magnetic field strength at a first predetermined location substantially on the chamber lid and a corresponding series of measurements of magnetic field strength at a second predetermined location within the chamber, the external magnetic field is correlated to the internal magnetic field to establish a function which when applied to external magnetic field measurements taken at the first predetermined location yields the magnetic field inside the chamber at the second predetermined location. This indirect measurement of the magnetic field inside the chamber is then utilized in a calibration routine for establishing the response of the magnetic field drivers.
DESCRIPTION OF THE DRAWINGS
[0015] The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
[0016] [0016]FIG. 1 is a diagram of portions of a typical reactive ion etching chamber including plasma chamber and magnetic drive coils;
[0017] [0017]FIG. 2 is a section schematic of a reactive ion etching system set-up suitable for conventional magnetic field calibration;
[0018] [0018]FIG. 3 is a section schematic of a reactive ion etching system set-up suitable for magnetic field calibration according to the present invention;
[0019] [0019]FIG. 4 is a flow diagram illustrating steps to establish the correlation between magnetic field measurements taken outside and inside a plasma; and,
[0020] [0020]FIG. 5 is a flow diagram illustrating steps to apply the correlation established between magnetic field measurements taken outside and inside a plasma in a calibration of the plasma chamber magnetic coils.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] According to the present invention, calibration of a magnetically enhanced reactive ion etcher is accomplished in a non-invasive manner. Unless independent necessity dictates that the plasma chamber needs to be opened, the present invention provides for magnetic field measurements to be taken outside of the plasma chamber. Thus, venting of the chamber, removal of the chamber lid, gas distribution plate and process kit is avoided. Similarly, unnecessary wet cleaning of the chamber, lid and gas distribution plate as well as other ancillary maintenance required when the plasma chamber is opened and compromised is avoided.
[0022] With further reference now to FIG. 3, a magnetically enhanced reactive ion etching apparatus 200 , identical in all respects to the apparatus illustrated in FIG. 2, is additionally shown with the lid assembly 60 in place. Lid assembly 60 includes gas distribution plate 62 through which process gas flows. All other features illustrated in FIG. 3 correspond to the same numbered features illustrated in and described with respect to FIG. 2. Repetition of description of such common features as between FIGS. 2 and 3 is therefore not undertaken herein.
[0023] It is noted that FIG. 3, as distinct from FIG. 2, illustrates a calibration set-up in accordance with the present invention. While the calibration set-up illustrated in FIG. 2 has such features or characteristics as (a) an open chamber (lid open or removed), (b) calibration tool 40 , and (c) magnetic probe 50 indexed to calibration tool 40 locating feature 46 , the calibration set-up illustrated in FIG. 3 avoids such disadvantageous features and characteristics. To wit, the set-up of FIG. 3 advantageously leaves the lid assembly 60 in place thus maintaining the integrity of the plasma chamber, requires no intrusion into the plasma chamber by a calibration tool or magnetic probe thereby avoiding the significant penalties associated with an intrusive calibration set-up previously described.
[0024] The set-up of FIG. 3 merely requires a repeatable placement of the magnetic probe 50 relative to the apparatus 200 . Preferably, that placement is at a place above the lid assembly with a further preference that it be substantially immediately adjacent the lid assembly 60 , though spaced adjacencies are acceptable, and relatively central to the placement of the coils surrounding the chamber. Such preferred placement would therefore place the probe in contact with the lid assembly such that the probe is equidistant from each coil of an opposing coil pair or symmetrically located with respect to all coils. Repeatable location of the probe may be accomplished by locating the probe within a footprint marking of the preferred location or within mounting features or fixturing machined into or added onto (removably or permanently) the lid assembly.
[0025] It has been discovered that such repeatable set-ups allow for magnetic field measurements taken otherwise as described with respect to the set-up of FIG. 2 to merely be adjusted by a factor and then used directly in the remainder of the calibration routine. That is to say, a weighting of the magnetic field measurements taken in accordance with the set-up of FIG. 3 returns a product which is substantially equivalent to a corresponding measurement if taken in accordance with the set-up of FIG. 2. These factors or weights may be derived experimentally with relatively little effort and are generally represented by a ratio of the magnetic field measurements taken in accordance with the respective set-ups as generally exemplified in FIGS. 2 and 3.
[0026] Tables I through VI below represent six sets of magnetic field measurement data. Each table shows one group of data corresponding to measurements taken inside a chamber and one group of measurements taken outside a chamber in accordance with the teachings herein. All magnetic field data measurements are in gauss. All tables represent magnetic field data measurements collected from production use Applied Materials® Centura® platform chambers. The specific chamber type appears at the top of the table.
[0027] Table I represents measurements taken on one Super-e chamber while Table II represents the same type of measurements on a different Super-e chamber. Similarly, Table III represents measurements taken on one eM×P+chamber while Table IV represents the same type of measurements on a different eM×P+chamber. And, Table V represents measurements taken on one M×P chamber while Table VI represents the same type of measurements on a different M×P chamber.
[0028] For Tables I and II, it can be seen that magnetic field data corresponding to both polarities of coil setting voltages (+/−) at magnitudes of 2.5V and 5V were collected. This is so because the manufacturer's software screens for the Super-e chamber requires magnetic field data in such a manner. From analysis of Table I, the data collected outside the chamber are seen to bear a repeatable relationship to the data collected inside the chamber. An average ratio of the outside chamber measurements to the coil inside chamber measurements is substantially 0.55, and this result is substantially consistent with individual measurement ratios. For example, for a −2.5 V coil setting, the ratio of the coil 2 outside chamber measurement (−13.3) to the coil 2 inside chamber measurement (−24.4) is substantially 0.55 (within +/−10% thereof). Similarly, for a 5V coil setting, the ratio of the coil 1 outside chamber measurement (25) to the coil 1 inside chamber measurement (45.5) is also substantially 0.55. Other similar comparative pairs of measurements for the remaining data yield similar repeatability for the same chamber.
TABLE I Chamber Type: Super-e Chamber Number: 1 Coil Setting → −2.5 V 2.5 V −5 V 5 V Magnetic Field Coil 1 −22.8 22.8 −45.6 45.5 Inside Chamber Coil 2 −24.4 24.7 −50.2 50.1 Coil 3 −22.8 22 −48.9 48.8 Coil 4 −25.5 25.3 −50.5 49.5 Magnetic Field Coil 1 −12.4 12.4 −24.7 25 Outside Coil 2 −13.3 13.4 −26.5 27.4 Chamber Coil 3 −13.4 13.5 −27 26.8 Coil 4 −13.8 13.8 −27.5 27.3
[0029] Chamber to chamber repeatability for substantially equivalent chamber types is borne out by analysis of similar comparative pairs of measurements for different chambers. For the present example using Super-e chambers, Table II illustrates that the exemplary underlined pairs of measurements also confirm a ratio of outside chamber measurement to inside chamber measurement of substantially 0.55. This ratio of outside to inside measurements may therefore be utilized as a weight or factor to derive or estimate inside chamber measurements from outside chamber measurements.
TABLE II Chamber Type: Super-e Chamber Number: 2 Coil Setting → −2.5 V 2.5 V −5 V 5 V Magnetic Field Coil 1 −23 24 −46.5 47.4 Inside Chamber Coil 2 −25.1 24.8 −49.6 49.5 Coil 3 −23.6 23.4 −48.3 47.1 Coil 4 −24.4 25.3 −49.3 50.2 Magnetic Field Coil 1 −12.6 13.1 −25.6 26.1 Outside Coil 2 −13.8 13.6 −27.3 27.2 Chamber Coil 3 −12.98 12.9 −26.5 25.9 Coil 4 −13.4 13.9 −27.1 27.7
[0030] To validate the general applicability of the discovered repeatable correspondence between inside chamber and outside chamber measurements, different chamber types were also subjected to data collection and analysis of a similar variety. For example, for Tables III and IV, it can be seen that magnetic field data corresponding to coil voltage settings of 2.5V, 5V, 7.5V and 10V were collected. In the case of this second type of chamber, a eM×P+chamber, the opposing coil pairs were energized simultaneously thus yielding side-to-side measurements and front-to-back measurements in contrast to individual coil measurements as in the previous example with respect to the Super-e chamber. This is so because the manufacturer's software screens for the eM×P+chamber requires magnetic field data in such a manner. From analysis of Table III, the data collected outside the chamber is seen to bear a repeatable relationship to the data collected inside the chamber. An average ratio of the outside chamber measurements to the inside chamber measurements is substantially 0.55, and this result is substantially consistent with individual measurement ratios. For a 2.5 V coil setting, the ratio of the front-to-back outside chamber measurement (25.8) to the front-to-back inside chamber measurement (46.5) is substantially 0.55. Similarly, for a 10V coil setting, the ratio of the side-to-side outside chamber measurement (108.4) to the side-to-side inside chamber measurement (194) is also substantially 0.55. Here, too, similar comparative pairs of measurements for the remaining data yield similar repeatability for the same chamber.
TABLE III Chamber Type: eMxP+ Chamber Number: 3 Coil Setting → 2.5 V 5 V 7.5 V 10 V Magnetic Field Side-to-side 50.2 100.2 147. 194 Inside Chamber Front-to-back 46.5 95.3 141. 186 Magnetic Field Side-to-side 27.5 55.8 83.5 108.4 Outside Front-to-back 25.8 52.5 78.5 101.5 Chamber
[0031] Chamber to chamber repeatability is borne out by analysis of similar comparative pairs of measurements for different chambers of the same chamber type. For the present example using eM×P+chambers, Table IV illustrates that the underlined pairs of measurements also confirms a ratio of outside chamber measurement to inside chamber measurement of substantially 0.55.
TABLE IV Chamber Type: eMxP+ Chamber Number: 4 Coil Setting → 2.5 V 5 V 7.5 V 10 V Magnetic Field Side-to-side 50.2 100.2 147.4 194 Inside Chamber Front-to-back 46.5 95.3 141.1 186 Magnetic Field Side-to-side 27.8 55.6 81.8 107.6 Outside Front-to-back 25.8 52.8 78.3 103.2 Chamber
[0032] As further validation of the general applicability of the discovered repeatable correspondence between inside chamber and outside chamber measurements, yet another set of different chamber types were subjected to data collection and analysis of a similar variety. Tables V and VI show magnetic field data corresponding to coil voltage settings of 2.5V, 5V, 7.5V and 10V were collected. In the case of this third type of chamber, a M×P chamber, the opposing coil pairs were, similar to the eM×P+chamber, energized simultaneously yielding side-to-side measurements and front-to-back measurements in contrast to individual coil measurements as in the twice removed example with respect to the Super-e chamber. Again, the manufacturer's software screens' data requirements defined the manner and type of magnetic field measurements. From analysis of Table V, the data collected outside the chamber is seen to bear a repeatable relationship to the data collected inside the chamber. An average ratio of the outside chamber measurements to the inside chamber measurements is substantially 0.48, and this result is substantially consistent with individual measurement ratios. For a 2.5 V coil setting, the ratio of the front-to-back outside chamber measurement (21) to the front-to-back inside chamber measurement (44) is substantially 0.48. Similarly, for a 10V coil setting, the ratio of the side-to-side outside chamber measurement (92) to the side-to-side inside chamber measurement (193) is also substantially 0.48. Here, too, similar comparative pairs of measurements for the remaining data yield similar repeatability for the same chamber.
TABLE V Chamber Type: MxP Chamber Number: 5 Coil Setting → 2.5 V 5 V 7.5 V 10 V Magnetic Field Side-to-side 46.5 98.2 147.6 193 Inside Chamber Front-to-back 44 94 141 186 Magnetic Field Side-to-side 22.2 46.7 70 92 Outside Front-to-back 21 45 67.1 88.5 Chamber
[0033] Once again, chamber to chamber repeatability is borne out by analysis of similar comparative pairs of measurements taken from a different chamber of the same chamber type. For the present example using M×P chambers, Table VI illustrates that the underlined pairs of measurements also confirm a ratio of outside chamber measurement to inside chamber measurement of substantially 0.48.
TABLE VI Chamber Type: MxP Chamber Number: 6 Coil Setting → 2.5 V 5 V 7.5 V 10 V Magnetic Field Side-to-side 45.9 99 145.3 192 Inside Chamber Front-to-back 46.2 93.6 136.5 180 Magnetic Field Side-to-side 21.8 47.1 69.1 91.4 Outside Front-to-back 21.9 44.5 65 85.6 Chamber
[0034] The steps to establishing the correlation between the outside and inside measurements having been described in detail will now be summarized in conjunction with the flow diagram of FIG. 4, and the application of such correlation described in conjunction with the flow diagram of FIG. 5.
[0035] Turning to FIG. 4, the flow diagram begins at step 401 . First, a position is established for the magnetic probe ( 403 ). Internal chamber measurements conventionally require use of a calibration tool previously described for repeatably locating the probe. External chamber measurements requires establishing a similarly repeatable location for the probe. As described earlier, This is preferably on the outer lid surface and central with respect to each respective opposing coil pairs. For repeatability a visual footprint may be established to indicate the desired placement or some type of locating, attachment, or robotic placement may be affected so that subsequent calibrations of the chamber magnetic field can be repeated using the weights or factors once determined. Data is then collected (405) in accordance with the manufacturer's or calibration routine's requirements. For example, if the manufacturer's software screens requires measurements for each coil at four drive voltages for entry into the calibration screen then the data collection should be accomplished in the manner to meet such requirements. Internal measurements are taken in accordance with the internal placement of the probe and external measurements are taken in accordance with the external placement of the probe. Next, the outside measurements are correlated to the outside measurement to establish the relationship there between and provide a function, factor or weight which when applied to outside measurements yield results which would be obtained if the same measurements had been taken inside the chamber ( 407 ). Step 409 marks the end of the steps to establishing the correlation between the outside and inside measurements.
[0036] The flow diagram illustrated in FIG. 5 represents the manner of utilizing the correlation established in the steps of the flow diagram illustrated in FIG. 4. Step 503 requires the operator to locate the probe to the repeatable location established outside of the chamber whereat measurements are to be taken. Magnetic field measurements are then taken outside the chamber just as described in step 405 of FIG. 4. The function, factor or weight established for the chamber in the correlation steps previously described is then applied to the measurements taken in step 505 . This yields adjusted data which correspond to magnetic field measurements which would have resulted had the measurements been taken within the chamber. These data are then input, such as by manual entry to the manufacturer's software screen, into a calibration routine ( 509 ). Step 511 represents the performance of the calibration routine which establishes the appropriate voltage or current required to drive each coil to a desired magnetic field in a manufacturing process. Step 513 marks the end of the steps of the flow diagram.
[0037] The invention has been described as establishing a single function, factor or weight for generally applicability to all magnetic measurements taken outside the chamber. However, it is envisioned that multiple such functions, factors or weights may be applied individually to certain magnetic field measurements to achieve the desired correlation results. For example, asymmetric probe positions (with respect to magnetic coils) may be required where chamber lid geometries or other apparatus features do not allow symmetric placements thereby resulting in functions, factors or weights that differ substantially from one coil measurement to the next. When used herein, the terms factor, weight or function are understood as equivalent in as much as each, when applied to outside measurements, returns or yields a result that is substantially equivalent to corresponding measurements which would result if taken inside the chamber.
[0038] The invention has been described with respect to a preferred embodiment intended to be taken by way of example and not by way of limitation. Certain alternative implementations and modifications may be apparent to one exercising ordinary skill in the art. Therefore, the scope of invention as disclosed herein is to be limited only with respect to the appended claims.
[0039] The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.
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A method of calibrating the magnetic coils of a magnetically enhanced reactive ion etcher includes taking magnetic field measurements outside of a closed plasma chamber and correlating such measurements to the magnetic field within the chamber. One or more factors are established which when applied to measurements taken externally yield results representative of measurements taken internally.
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