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This is a continuation, of application Ser. No. 526,121, filed Aug. 24, 1983, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is in the field of chemical cooking of wood chips to produce pulp suitable for manufacture of paper and involves sequential use of various cooking liquors in the same digester for predetermined cooking times, to increase the efficiency of the process and to conserve energy.
2. Description of the Prior Art
There are numerous types of processes for batch digestion of wood chips in the manufacture of paper. The digestion usually takes place in a digester specifically built for that purpose, the digester being filled with the wood chips which are usually compacted therein. Hot solutions of sodium hydroxide alone or in admixture with sodium sulfide are then charged into the digester. The temperature of the digester can be controlled through the introduction of steam and after maintaining the chips in contact with the cooking liquor for a predetermined period of time, a blow valve in the digester can be opened to dump the contents into a blow tank.
There is a substantial amount of heat loss in carrying out the batch digestion process and while many systems have been suggested for minimizing this heat loss, none has been particularly effective. Some paper manufacturers have gone to continuous digesting processes in order to improve the efficiency of the cooking operation, but the equipment costs for a continuous digesting system are very high.
More recently, an improved type of batch process has been designed for overcoming these difficulties. In this new process, the wood chips are cooked in the digester and the hot black liquor which results is removed by displacement with a filtrate from the washing section. This filtrate is added to the bottom of the digester and pushes up the hot spent liquor through the chip column without a substantial intermingling of the two liquids. The displaced hot black liquor is then directed into a pressurized accumulator. The digester is then emptied by adding steam to the top of the digester which forces the pulp out through a blow valve into a blow tank. After the pulp has been blown from the digester, it is uniformly filled with chips.
Hot black liquor from the accumulator is pumped into the bottom of the digester where it heats the chips. In this stage, an excess of black liquor is employed, more than the capacity of the digester so that excess black liquor is discharged from the top of the digester and is transferred to a weak black liquor tank. Fresh white liquor is then used to displace the black liquor from the bottom of the digester and the resulting spent liquor is passed to a weak black liquor storage space. The contents of the digester are then heated with steam to the desired cooking temperatures and held there for the required cooking times. When the contents of the digester have reached the cooking temperature, the steam introduction stops. After cooking, the hot liquor is removed as in the originally described step, and the cycle starts over again. This type of process is described in Fagerlund Application Ser. No. 434,758, filed Oct. 18, 1982, now U.S. Pat. No. 4,578,149 and assigned to the assignee of the present application.
SUMMARY OF THE INVENTION
The present invention provides a multi-stage wood chip cooking process utilizing a single digester wherein the wood chips are introduced into the digester and soaked in a warm black liquor to remove most of the air from the digester and the chips. After a suitable soaking period, the warm black liquor is displaced from the digester with a mixture of a first hot black liquor and hot white liquor having a relatively high proportionate amount of white liquor. The temperature of the digester contents is raised to a cooking temperature usually by circulating the contents through a heat exchanger through which steam is added. After a suitable cooking period which will be the longest of the multi-stage process, the liquor is displaced from the digester with a mixture of a second hot black liquor and hot white liquor. This mixture has a proportionate amount of hot white liquor lower than in the first liquor. The temperature of the digester is again raised to a cooking temperature and after the chips have attained a predetermined degree of cooking, the liquor is displaced in the digester with a liquid filtrate derived from pulp washing. Finally, the contents of the digester are emptied by applying gas pressure to the interior of the digester.
Stated more generally, the present invention involves a multi-stage wood chip cooking process in which the chips are sequentially cooked in a digester in a series of cooks C 1 , C 2 , C 3 . . . C n . The cook C 1 is carried out with a liquid L 1 having a relatively high proportionate amount of white liquor and for a relatively long cooking time T 1 . Cook C 2 is carried out with a liquor L 2 having a proportionate amount of white liquor less than L 1 and for a time shorter than T 1 . Succeeding cooks are carried out through cook C n with a liquor L n at successively lower proportionate amounts of white liquor and successively shorter times. As few as two stages can be used, but three are preferred. More than three can be used where necessary or desirable.
In the case of a three-stage process for pulping softwood chips using the kraft process, the following conditions may apply. The total white liquor may typically constitute about 25% of the liquid capacity of the digester minus the volume of chips in the digester. The first cooking is carried out with an amount of white liquor comprising, 50 to 75% of the total white liquor for a period of 25 to 40 minutes, the second cooking is carried out with an amount of white liquor comprising 10 to 30% of the total for a period of 10 to 20 minutes, and the third cooking is carried out with an amount of white liquor comprising 5 to 20% of the total for a period of 5 to 15 minutes.
BRIEF DESCRIPTION OF THE DRAWING
The single Figure of the drawing illustrates schematically an installation for carrying out the multistage wood chip cooking process of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the attached Figure of the drawing, reference numeral 10 has been applied generally to a digester of the conventional type including a removable lid 11. The contents of the digester can be heated to a cooking temperature by pumping them through a pump 12 and a valve 13 through a heat exchanger 14 having a steam inlet line 15 and a steam condensate outlet line 16.
A warm liquor accumulator 17 stores black liquor at a relatively low temperature. This warm black liquor, at a temperature substantially below that required for cooking, is initially pumped by means of a pump 18 through a line 19 controlled by a valve 20 into the base of the digester 10 through an inlet valve 21.
The system also includes a first hot liquor accumulator 22 which contains the liquor for the first stage cook. This black liquor at a relatively high temperature is pumped out through a pump 23 and proceeds through a valve 24, through the valve 21 and into the base of the digester. A hot white liquor accumulator 25 serves as a storage vessel for the fresh hot white liquor which is pumped out of the accumulator 25 by means of a pump 26 through a flow regulator 27 and is thereupon combined with the discharge of the pump 23 from the first hot black liquor accumulator 22. The flow regulator 27 can be used to set the relative proportions between hot white liquor and hot black liquor in the first cooking step.
The hot white liquor is preheated after it is introduced through an inlet line 28 through a heat exchanger 29 before entering the hot white liquor accumulator 25. The heat exchange is accomplished by withdrawing a portion of the hot black liquor from the accumulator 22 through a pump 30 and a line 31. This hot black liquor is also used as the heat exchange liquid for a second heat exchanger 32 which will be described subsequently. The hot black liquor passing through the two heat exchangers 29 and 32 is removed as a warm but not hot liquid through a line 33 whereupon it is delivered to the warm liquor accumulator 17. Periodically, the warm black liquor from the accumulator 17 is discharged through a line 66 and passed to a black liquor evaporator.
A second hot liquor accumulator 34 is used to store the black liquor for the second cook. A pump 35 delivers a stream of the hot black liquor which is at a lower temperature than the hot black liquor in the accumulator 22 into combination with hot white liquor from the accumulator 25. The hot white liquor is delivered by means of a pump 36 through a flow regulator 37 where it is combined with the discharge of the pump 35, the combined discharge then passing through a valve 38 and into the base of the digester through the valve 21. The relative proportion of hot white liquor in this cook will be less than the proportion used in the first cook, and the cooing temperature will be less. Steam is optionally introduced into the second hot liquor accumulator 34 by means of a steam line 39.
A third hot liquor accumulator 40 containing hot black liquor for the third cook is provided with a pump 41 for the discharge of its contents. A pump 42 associated with the hot white liquor accumulator 25 delivers a metered amount of hot white liquor through a line 43 and a flow regulator 44 into admixture with the hot black liquor being pumped through the pump 41. The combined stream passes through a valve 45, and through the valve 21 into the base of the digester 10. The combined stream for the third cook has a lesser concentration of white liquor than the previous cooking liquors and is at a lower temperature.
A pulp washer filtrate recovered from another portion of the papermaking plant (not shown) is introduced into an accumulator 46 through a line 47. A pump 48 is provided to deliver the filtrate through a valve 49 and into the base of the digester through the valve 21. A portion of the filtrate in the accumulator 46 may be pumped by means of pump 50 through a line 51 and then through the heat exchanger 32 where it is passed in heat exchange relationship with the hot black liquor from the first hot liquor accumulator 22. This preheated filtrate is then directed to a hot filtrate accumulator 52. A pump 53 delivers the heated filtrate through the valve 49 and into the digester 10.
Finally, there is provided a discharge valve 54 for emptying the contents of the digester 10. For this purpose, air or other fluid is introduced through an inlet line 55 at the completion of the cook, whereupon valve 54 is opened and the contents of the digester are transferred to a blow tank or another receptacle through a discharge line 56.
The various cooking liquors are then returned to the accumulators upon completion of the individual stages of the cook. A line 57 and valve 58 are used to return a weak cooking liquor to the warm liquor accumulator 17. A line 59 and a valve 60 are used to deliver hot black liquor to the first hot liquor accumulator 22. Similarly, a line 61 and a valve 62 return liquor from the digester 10 to the second hot liquor accumulator 34. Material is recycled to the third hot liquor accumulator 40 by means of a line 63 and a valve 64.
The process of the present invention can be used with a modified kraft or soda pulping process. The multi-stage system preferably consists of three stages as shown in the drawing but may employ two stages or more than three. The multi-stage cook removes the non-cellulosic material from the wood chips in a manner so as to improve the pulp yield, improve the pulp quality as measured by the average molecule size, and improve the pulp brightness. Additionally, this new process permits pulps produced for further processing by bleaching to be more completely delignified and thus require a milder bleaching treatment using reduced quantities of bleach chemicals. A further advantage of this invention is that most of the pulp washing to remove spent cooking chemical and dissolved organic matter is done in the digester.
The conditions of time, temperature and active cooking chemical concentration can, within reasonable limits, be adjusted between the stages of cooking so as to optimize the desired pulp properties from the wood chips being used. This feature provides greater flexibility in the pulping operation.
The following description is given to show the overall process sequence.
The empty digester 10 is filled by removal of the lid 11 with wood chips. These chips may be compacted in order to increase the quantity of chips charged, and to provide a more uniform chip density. It is preferable that overly thick chips (more than 6 millimeters) be removed from the chips supply.
With the digester 10 closed, warm black liquor from the accumulator 17 is pumped by means of pump 18 through the line 19 to the valve 21 into the bottom of the digester which is substantially filled with chips. The digester is completely filled with this liquor and some excess is supplied. The excess leaves the digester by means of an extraction screen (not shown) located in the top dome of the digester 10. The excess liquor is returned to the warm liquor accumulator 17 through the line 57. This initial soaking with the warm liquor at a temperature considerably below cooking temperature serves to remove most of the air from the digester and the chips, warms the chips, and neutralizes some of the organic acids associated with the wood chips. The excess weak black liquor generated in the pulping and washing system is periodically discharged to the black liquor evaporators through the discharge line 66.
Hot black liquor from the first hot black liquor accumulator 22 and hot white liquor from the hot white liquor accumulator 25 are pumped together by means of pumps 23 and 26, respectively, through the valve 24 into the bottom of the digester which is now filled with warm black liquor. The displaced warm liquor leaves the digester via the extraction screen in the top dome of the digester and is returned to the warm black liquor accumulator 17 through the line 57.
Liquor from the first hot black liquor accumulator 22 is not only used for filling the digester 10 but is also used to preheat the fresh white liquor in the heat exchanger 29 and also to preheat the first portion of the washer filtrate in the heat exchanger 32. The black liquor leaving the two heat exchangers goes to the warm liquor accumulator 17 by means of the line 33.
The hot white liquor entering through the line 28 is also heated by the heat exchanger 29 before it arrives at the hot white liquor accumulator 25.
The temperature of the contents of the digester 10 filled with the mixture of hot black liquor from the first hot liquor accumulator 22 and the hot white liquor accumulator 25 is raised to the desired cooking temperature by circulating the contents of the digester through the valve 13 and heat exchanger 14 under the action of the pump 12. Forced circulation of liquor in the digester is preferred to insure uniform distribution of temperature and chemicals throughout the digester 10. In the case of a kraft process cooking for the three-stage sequence, the first cooking can take place with a liquor containing 50 to 75% of the total white liquor used and a cooking time of 25 to 40 minutes. No cooking operation in this multi-stage process requires as much as a 60 minute cook.
At the conclusion of the desired first stage cooking time, hot black liquor from the second hot liquor accumulator 34 and hot white liquor from the accumulator 25 are pumped together through pumps 35 and 36, respectively, into the bottom of the digester 10. Proportioning of the relative amounts is accomplished by the flow controller 37. This second cooking liquor contains a lower proportionate amount of white liquor and is used for a lesser cooking time than the first cook. Typically, the second cooking is carried out with a white liquor constituting 10 to 30% of the total for a period of 10 to 20 minutes.
The digester is brought up to cooking temperature by circulating the liquor through the heat exchanger 14.
Alternatively, steam can be added to the second hot liquor accumulator 34 through the steam line 39.
At the expiration of the desired second stage cooking time, hot black liquor from the third hot black liquor accumulator 40 and hot white liquor through the pump 42 and flow regulator 44 are combined and pumped together through valve 45 into the base of the digester 10. The displaced black liquor leaves the digester 10 and passes through line 61 and valve 62 into the second hot black liquor accumulator 34.
The temperature of the digester contents filled with the hot black liquor and hot white liquor is then raised to the desired cooking temperature by circulating through the heat exchanger 14. Alternatively, the heat exchanger can be eliminated and the steam can be injected directly into a circulating line whereby the contents of the digester are withdrawn from the top and pumped into the bottom by means of the pump 12. As another alternative, steam can be added to the third black liquor accumulator 40.
Typical conditions for the third cooking cycle include a white liquor fraction of 5 to 20% of the total and a cooking time of 5 to 15 minutes.
At the expiration of the desired third stage cooking time, filtrate from the pulp washing operation is pumped into the bottom of the digester. The displaced black liquor leaves the digester from the top and goes to the third hot black liquor accumulator 40 through the line 63 and valve 64.
The first portion of the filtrate is pumped from the accumulator 46 through a pump 50 into heat exchange relationship with the hot black liquor circulating through the heat exchanger 32. Preheating the first portion of the filtrate reduces the total steam required in the pulping system, permits the wash water added to the liquor system to be efficiently used by counter-current flow and maintains a low concentration of black liquor in the final cooking stages.
After the hot black liquor has been displaced from the third stage cook with the washer filtrate, compressed air is introduced through a line 55 into the top of the digester and the contents of the digester, pulp and washer filtrate are forced out of the bottom of the digester through a valve 54 into a suitable storage chest or blow tank by means of the line 56. The discharge of the chips from the digester by means of a curtain of air is more fully described in my co-pending application Ser. No. 402,636, filed July 28, 1982.
Typical cooking conditions for a three-stage process pulping softwood chips using the kraft process are given in the following table:
______________________________________ Total Final % Total Cooking Maximum Final Black White Time Cooking Pulp LiquorStage Liquor (min.) Temp. °F. Kappa Nr. Solids, %______________________________________First 69 50 340 100 25Second 22 30 338 40 12Third 9 25 335 25 4______________________________________
The present invention permits the use of relatively short total cycle times and thus improves pulp production rates. Typical times for the various functions in a three-stage process according to the present invention are:
______________________________________Function Time in Minutes______________________________________Chip Filling 15Warm Liquor Fill 20First Hot Liquor Fill 15First Stage Cook 35Second Hot Liquor Fill 15Second Stage Cook 15Third Hot Liquor Fill 15Third Stage Cook 10Hot Liquor Displacement 20Blowing 15Spare 5Total Digester Cycle Time 180______________________________________
While the drawings illustrate a three-stage process and this is the preferred embodiment, the invention is more general than that. Basically, the invention involves a multi-stage wood chip cooking process in which the chips are sequentially cooked in a digester in a series of cooks C 1 , C 2 , C 3 . . . C n . The cook C 1 is carried out with a liquor L 1 having a relatively high proportionate amount of white liquor and for a relatively long cooking time T 1 . Cook C 2 is carried out with a liquor L 2 having a proportionate amount of white liquor less than L 1 and for a time shorter than T 1 . Succeeding cooks through cook C n are carried out in successively lower proportionate amounts of white liquor and successively shorter times.
The total quantity of white liquor used in a digester is determined by (1) the degree of pulping or extent of delignification desired, (2) the quantity of wood chips charged on an oven dry basis, and (3) the concentration of the active cooking chemicals, sodium hydroxide and sodium sulphide, in the white liquor. For example, it is found that an active cooking chemical application, expressed as sodium oxide, of 15% on oven dry wood is required to achieve a properly delignified pulp. In a 6,000 cubic foot digester containing 60,000 pounds of bone dry wood there is a need for 15 percent of 60,000 or 9,000 pounds of active alkali. The volume of white liquor, found by test to contain 6.0 pounds of active alkali per cubic foot, required for the charge is then calculated to be 1,500 cubic feet.
In the above example, the entire quantity of white liquor is added to the charge in the initial filling operation in a conventional batch pulping system. With the new multi-stage process, assuming the same total white liquor usage, the application in a three-stage system could be as follows:
______________________________________ White Liquor Percent ofStage Charge Total Charge______________________________________First 1,000 cu. ft. 66.7%Second 300 cu. ft. 20.0%Third 200 cu. ft. 13.3%Total 1,500 cu. ft. 100.0%______________________________________
It will be evident that various modifications can be made to the described embodiments without departing from the scope of the present invention. | A multi-stage wood chip cooking process performed in a single digester in a batch type operation. The wood chips to be cooked are introduced into the digester and soaked with a warm black liquor to remove most of the air from the digester and the chips. This warm black liquor is thereafter displaced from the digester with a mixture of a first stage hot black liquor and hot white liquor, the proportionate amount of hot white liquor being relatively high. The temperature of the digester contents is then raised to a cooking temperature for a predetermined amount of time. The original cooking liquor is then displaced with a mixture of a second hot black liquor and hot white liquor, the proportiionate amount of hot white liquor in this second cooking liquor being less than in the first. Again, the temperature of the digester is raised to a cooking temperature and the cooking is carried out for a shorter period of time than in the first cooking stage. After the required number of cooks which may be preferably three but may be aas low as two or more than three, the cooking liquor is displaced from the digester with a liquor filtrate derived from pulp washing. Finally, the contents of the digester are emptied by applying gas under pressure to the interior of the digester. | 3 |
BACKGROUND OF INVENTION
1. Field of the Invention
This invention relates generally to refrigerator systems for transportable vehicles, and more particularly to a method and apparatus for utilizing carbon dioxide in a chamber in trucks, rail cars and the like for transporting frozen food without mechanical refrigeration units.
2. Description of the Prior Art
Refrigeration systems for railroad cars and trucks have typically utilized mechanical refrigeration units. In such mechanical refrigeration units it is always of great concern that the units are operational and would not breakdown. The cost of maintenance, both in time and dollars, is often substantial. In addition, over a long haul, it is necessary to frequently check the mechanical refrigeration system to make certain that they are still operational. Further, the mechanical works and fuel add to the overall weight of the rail car.
Non-mechanical refrigeration units have been proposed, but they have been mainly suitable only for trucks. One such non-mechanical refrigeration system is disclosed in U.S. Pat. No. 3,561,266 and was issued to Julius Rubin on Feb. 9, 1971. This non-mechanical refrigeration system utilized liquid CO 2 that is converted into solid dry ice, often referred to as snow. Liquid CO 2 is injected into one end of a cold plate container at the time refrigeration is desired in a given chamber. The liquid CO 2 is converted to snow and CO 2 vapor. The cold plate would act as a source of refrigeration for the truck. While the Rubin patent does disclose that such a CO 2 cold plate system could be used for railroad cars, such a system has never proved practical.
Another example of a CO 2 charged cooling unit is disclosed in U.S. Pat. No. 4,248,060 issued to Paul Franklin, Jr. on Feb. 3, 1981. The Franklin patent discloses a cooling cabinet utilizing CO 2 snow and having associated therewith a passageway structure for pumping air to provide for cooling in the area surrounding the cooling unit.
In both of the above noted prior arts units, the CO 2 snow was directly used as the refrigerant for the cooling chamber. The vapor of the CO 2 snow as it evaporates was typically vented to the outside and not used directly used as the source of cooling.
The present invention addresses the problems of the prior art refrigeration systems.
SUMMARY OF THE INVENTION
The present invention is an apparatus and method for transporting frozen products in a refrigerated rail car, truck or the like. The rail car or truck has a ceiling, floor, two end walls and first and second sidewalls cooperatively connected to form an enclosed storage area. Means for containing solid refrigerant flakes is positioned proximate the ceiling of the enclosed storage area.
Also included is means for transferring liquid CO 2 to the container means and means for converting the liquid CO 2 into the solid refrigerant flakes and directing the flakes into the container means. Means for allowing the vapor, when the solid refrigerant flakes sublimate, to exit the containment means to the storage area is provided. The exit means is positioned proximate the first sidewall. The sidewalls have means for channeling a flow of air, including the vapor and the floor has means for directing the flow of air from the first sidewall to the second sidewall, wherein when the refrigerant flakes sublimate in the containment means, the vapor flows from the containment means out of the exit means, down the channel means of the first sidewall, across the directing means and up the channel means of the second sidewall, all by convection only.
The method is for refrigerating an enclosed area adapted for transporting frozen cargo, the enclosed area having a bunker position proximate the top of the frozen area. The method includes transferring liquid CO 2 to the bunker and converting the liquid CO 2 to solid refrigerant flakes. The flakes are directed into the bunker. The vapor, when the flakes sublimate, are allowed to exit the bunker proximate one of the sidewalls of the enclosed area. A convection air flow is set up in the enclosed area wherein the convection flow starts by the vapor leaving the bunker, going down one of the sidewalls, through a channel in a floor and up another sidewall.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a refrigerated rail car incorporating the present invention.
FIG. 2 is a cross-sectional view of the rail car FIG. 1 taken generally along the lines 2--2.
FIG. 3 is a cross-sectional view of the rail car FIG. 1 taken generally along the lines 3--3.
FIG. 4 is a cross-sectional view of the rail car FIG. 1 taken generally along the lines 4--4.
FIG. 5 is a cross-sectional view of the rail car shown in FIG. 3, taken generally along the lines 5--5.
FIG. 6 is a cross-sectional view of the rail car of FIG. 1 taken generally along the lines 6--6.
FIG. 7 is a cross-sectional view of the rail car of FIG. 3, taken generally along the lines 7--7.
FIG. 8 is a cross-sectional view of the rail car of FIG. 4, taken generally along the lines 8--8.
FIG. 9 is a cross-sectional view of the rail car of FIG. 3, taken generally along to lines 9--9.
FIG. 10 is a cross-sectional view of the rail car of FIG. 8, taken generally along the lines 10--10.
FIG. 11 is a cross-sectional view of the rail car of FIG. 5, taken generally along the lines 11--11.
FIG. 12 is a cross-sectional view of the rail car of FIG. 4, taken generally along the lines 12--12.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the figures, wherein like numerals represent like part throughout the several views, there is generally illustrated at 10 a refrigeration rail car. The refrigeration car 10 is shown without wheels or an undercarriage, it being understood that any suitable undercarriage may be utilized. The rail car 10 has a first sidewall 11, second sidewall 12, first endwall 13, second endwall 14, floor 15 and ceiling 16 all cooperatively connected to define a storage area 17 in which the products to be transported are located. Access to the storage area 17 is provided by sliding doors 18, as is well known in the art. A door 18 is positioned proximate the middle of each sidewall 11 and 12. Insulation 19 may be cooperatively connected to or between the walls of the rail car 11 to provide for an insulated storage area. The outer structure of the rail car 10, as just described, is well known in the art and any suitable outer construction of the rail car may be utilized.
A bunker, generally illustrated at 20, is constructed proximate the top of the storage area 17. A plurality of U-shaped aluminum beams 21, with a wooden filler 21a, are secured between the sidewalls 11 and 12. The beams 21 provide for support for the bunker 20. The ceiling of the bunker 20 is a sheet of suitable material such as Kemlite BES 485, illustrated at 22. A plurality of ceiling pans 23 are used to construct the remaining outer shell of the bunker 20. As can be seen in FIGS. 3, 8 and 10, the ceiling pans 23 have a base section 23a that extends across the width of the bunker 20. An upwardly extending section 23b is cooperatively connected to the base section 23a and extends to the Kemlite ceiling 22. A top section 23c is cooperatively connected to the section 23b and conforms to the shape of the ceiling 22. The inner wall of the sidewall 12 forms the other wall of the bunker 22. As shown in FIGS. 8 and 10, a portion of the section 23b rests on the beam 21. Insulation 24 is cooperatively connected to the section 23b by means of a sheet of Kemlite 25 and secured by plurality of screws 26. A wooden board filler 27 is positioned between the Kemlite 25 and insulation 24 where the screws 26 are located. FIG. 12 is an enlarged detailed view of this construction. The insulation 24 may be any suitable insulation, such as a 11/2 inch thick foam board insulation having a density of from 1.8 to 2.0 pounds. A closure member 28, as shown in FIGS. 8 and 10 is connected to the ceiling pan 23 by means of pop rivets 29 and to the Kemlite panel 25 by pop rivets 29.
The section 23b of the ceiling pans 23 has a mesh screen opening 30 through which the CO 2 vapor may exit the bunker, as will be more fully described hereafter. The mesh screen 30 provides the only exit for the vapor from the bunker 22. The mesh screen 30 may be held in position over the opening in the section 23b by any suitable means, such as frame assembly 31. In addition, there is an opening in the section 23b through which nozzels 75 are positioned. As can be seen in FIG. 3, the mesh screen 30 is positioned proximate the sidewall 11. The bunker 22 is of sufficient size to carry a suitable load of CO 2 flakes as would be necessary for the desired length of time that the storage area is to be cooled. This would of course depend on the outside temperature of the air, the insulated values of the outer walls of the rail car and other relevant factors. For a typical rail car the bunker may be approximately 52 feet by 8 feet and having sufficient cubic capacity to hold 9,000 pounds of CO 2 flakes.
The sidewalls 11 and 12 are of a similar construction and therefore only the construction of the sidewall 11 will be detailed, it being realized that similar construction is used for sidewall 12. As can be seen in FIGS. 5, 7 and 11, attached to the inner wall 11a of the sidewall 11 are a plurality of protruding strips 32. Each strip 32 has two sections 32a that extend into the storage space 17. Flanges 32b are formed on the outside of the strips 32 with an inner flange 32c connecting the two protrusions 32a. The strips 32 are then cooperatively connected to the inner wall 11a by means of an appropriate fastening mechanism, such as rivets 33. The spaces between the protrusions 32a form channels 34. A Kemlite kick board 35 is cooperatively connected to the bottom portions of the strips 32 by screws 36. The protrusions 32a do not extend to the floor of the rail car as shown by the diagonal line in FIG. 11. Below the end of the protrusions 32a is placed a roll of stainless steel or aluminum screening material 37 that is positioned against the inner wall of the kick board 35 and the inner wall 11a. The open mesh nature of screen 37 allows for the passage of air through the screen 37 as air flows through the channels 34. A steel support bar 38 is welded to the floor material (to be more fully described hereafter) to form a support for the bottom of the kick board 35. A cauking material is placed around the perimeter of the support bar 38 to effectively seal between the floor and the Kemlite kick board 35.
The end wall 13 is similarily constructed with strips 32 having protrusions 32a, flanges 32b and 32c that are cooperatively connected to the inner wall 13a of end wall 13, forming channels 34. A vent, which is designated at 39 is positioned in the top portion of the end wall 13. The vent 39 has a hollow tube 39a that may be of any suitable configuration. As shown in the drawings, the tube has a generally square cross section. However, it is understood that other suitable configurations may be used. The tube 39a has a first opening 39b that is always open to the interior of the storage area 17. A second opening 39c is covered by a door 39d that is connected to the tube 39a by a hinge 39e. When the door 39d is in an open position, the opening 39c is vented to the atmosphere.
The other end wall 14 is of a similar construction to the first end wall 13, except there is no vent 39. However, it is understood that it would be possible to have the vent 39 in any one wall 11, 12, 13 or 14 as well as in more than one of the walls.
The flooring, generally designated at 40, for the enclosed area 17 is positioned over the floor 15 and insulation 19. The flooring 40, as shown in FIGS. 5, 6, 9 and 11 consist of a plywood subfloor 41 cooperatively connected over the insulation 19 to the floor 15 in any manner, well known in the art. Metal bars 42 are secured to the plywood 41 by screws 43. The metal bars 42 extend generally the length of the rail car 10. While seven metal bars 42 are shown, it is understood that any suitable number may be utilized. Nailable steel plank flooring 44 is welded in place along the metal bars 42. One such nailable steel floor is National Steel Corporation EPR-211 nailable steel floor. In addition to being welded to the metal bars 42, the top surface of adjacent flooring strips 44 are intermitantly spot welded for added strength. A cross-sectional view of the nailable flooring strip 44 is best seen in FIG. 9. The flooring strip 44 has base section 44a, a generally upright section 44b and a top surface 44c. A generally U-shaped support member 44d is cooperatively connected to the top section 44c. The ends of the flooring strips 44 are not covered, therefore it can be seen that there are air flow channels 44e formed in the interior of the flooring strip 44. As seen in FIGS. 6 and 11, support bars 76 are cooperatively connected to the ends of the strips 44, but only in the location of the door 18. The bars 76 are therefore only in the center of the rail car 10. Further, there is a space between the two bars 76 to allow for air flow to channels 44e. Adjacent each end wall 13 and 14 is an inverted U-shape drainage member 45. As shown in FIG. 9, the drainage member has two downwardly depending flanges 45a and a cross member 45b. The cross member 45b has a plurality of drainage holes 45c. It is understood that any suitable drainage member 45 may be utilized, such as a drainage member that would be in the general configuration of a rack having an open mesh top to allow for even more drainage through the open mesh. The inner cavity of the drainage member 45 is open to a drainage tube 46 that has a threaded base member 46a and a removable threaded cap 46b. It is understood that the drains are open and used only during cleaning, otherwise they are plugged and insulated during shipment.
The loading manifold, designated generally as the 50, is shown in FIG. 2. The loading manifold 50 is positioned on the rail car 10 such that the manifold may be accessed from either side of the rail car 10. The loading manifold 50 has a first loading end 50a and a second loading end 50b. Both loading ends 50a and 50b are in fluid communication with the supply line 51. The supply line 51 is in fluid communication with the supply manifold, generally designated as 70 as shown in FIG. 4, and will be more fully described hereafter. Both the first loading end 50a and second loading end 50b are connected to the supply line 51 in the same manner. Therefore, only the connection from the first loading end 50a to the supply line 51 will be described, it being realized that a similar connection connects the second end 50b to the supply line 51.
The first end 50a of the loading manifold 50 includes an adaptor 52 having a male end 52a and a female end 52b. The male end 52a can be connected to the source of liquid refrigerant (not shown). The source of liquid refrigerant may be any source, well known in the art. It is preferred that a tank of CO 2 be available proximate the railroad tracks and a hose simply be brought from the tank to the loading ends 50a or 50b. It is also possible to use a mobile tank for smaller uses or in more remote locations. A strainer 53 is cooperatively connected to the adaptor 52 by means of an elbow 54 and adaptor 56. The loading manifold 50 is cooperatively connected and supported to the railcar 10 by means of suitable mounting brackets 55. The mounting brackets 55 have mounting members 55a which encircle and support the loading mainfold 10. A pressure relief valve 57 is cooperatively connected to the other end of the strainer 53 by means of a tee 58 and adaptor 56. A bleed off valve 59, having a handle 59a, is cooperatively connected to the pressure release valve 57 by means of a tee 58 and adaptor 56. A first end of a shut off valve 60, having a handle 60a, is cooperatively connected to the bleed off valve 59 by an adaptor 56 and the other end of the shut off valve 60 is cooperatively connected to the supply line 51 by an adaptor 56 and tee 58.
The supply line 51 is cooperatively connected to the supply manifold 70. The supply manifold 70 includes a supply pipe 71 and a distribution pipe 72. The supply pipe 71 is cooperatively connected to the top portion of supply line 51 of the railcar 10. The supply pipe 71 extends approximately to the center of the rail car 10. A tee 73 is cooperatively connected to one end of the supply pipe 71 proximate to the center of the railcar. The tee 73 is in turn cooperatively connected to the tee 74 which is located proximate the center of the distribution pipe 72. The distribution pipe 72 includes a first section 72a that extends proximate one end of the railcar 10 and a second section 72b that extends proximate the other end of the rail car 10. Nozzles 75 are cooperatively connected at approxmately four foot intervals along the distribution pipe 72. The nozzles 75 are simple brass plugs with drilled holes or conventional CO 2 forming heads or nozzles. The number of the nozzles 75 will of course be dependent upon the overall length of the bunker that is filled with CO 2 snow. In a preferred embodiment where the supply pipe 72 is 52 feet long, the three nozzles adjacent the distal end first section 72a have an orifice of 0.161 inches and the remaining nozzles of section 72a and all of 72b have orifices of 0.156 inches. The nozzles 75 are supported in position by a suitable mounting bracket and generally are positioned at an upward angle of approximately 20° above the horizon for shooting the CO 2 snow into the bunker.
The supply manifold 50 is positioned outside of the enclosed area 17 at any suitable location. One manner of so doing, is shown in FIGS. 2 and 5. A compartment 47 is constructed adjacent the end wall of the rail car 10. Compartment 47 has three sidewall 47a and a top 47b and bottom 47c. An access door 48 is cooperatively connected to the one of the side walls 47a by means of a hinge 49 to provide access to the supply manifold 50.
The present invention is also well suited for adapting existing refrigerated cars that have previously been using mechanical system. The interiors of the cars may be suitable converted to conform to that of the present invention. In so doing, it would be possible to use the engine room of the mechanical refrigerator cars to house the supply manifold 50, as there is no longer any need for the mechanical workings with the present invention. The sidewalls 47a of the compartment 47 have openings through which the ends 50a and 50b protrude, so that they may be easily accessable for being filled with the liquid CO 2 .
In operation, a source of liquid CO 2 is brought up along either side of the rail car 10. The source of liquid CO 2 is attached to either of the ends 50a or 50b. Handle 60a is rotated to an open position, allowing the liquid CO 2 to flow through the loading manifold 50, through the supply line 51 and into the supply manifold 70. The liquid CO 2 flows from the supply line 51 into the supply pipe 71 where it then flows to the distribution pipe 72. The liquid CO 2 then flows to all sections of the distribution pipe 72 and flows from the distribution pipe 72 into the nozzles 75. The liquid CO 2 , as it exits the nozzles 75 turns to refrigerant flakes, commonly referred to as snow, and enters the bunker 20. Snow will continue to flow out of the nozzle 75 until the area in front of the nozzle 75 is filled and the back pressure, caused by the snow against the nozzle, will cause the liquid CO 2 to quit flowing out of the nozzle 75. Depending upon the supply manifold 70 used, it may be necessary to adjust the orifices of the nozzles 75 to provide for even distribution throughout the bunker 22. To obtain adaquate distribution, it is only necessary to have slightly different sized orifices to provide for better distribution. In the present case, it was found that by increasing the orifices of the three end nozzles a better distribution was obtained. However, it is understood that based on this specific configurations of the bunker and supply manifold, different sized orifices may be necessary throughout the supply manifold 70. During the loading of the CO 2 , sufficient vapor pressure may build up within the enclosed storage area so as to activate the vent 39. A build up of pressure will cause the door 39d to lift off of the bottom portion of the tube 39a, thereby venting the interior of the storage area to the atmosphere. Due the typical construction of rail cars, it has been found that during the transportation of the rail car, the vent 39 is not actuated. This is because there is sufficient leakage throughout the car to prevent the build up of vapor pressure. However, if in fact the vapor pressure does build up during the transportation of the rail car, the vent 39 would be actuated. It is understood that before the CO 2 is loaded into the storage area 17, that the cargo to be transported is first loaded into the rail car. Once the storage area is fully loaded, the sliding doors 18 can be closed to prevent further access by persons and the CO 2 may then be loaded. In such a manner, the CO 2 vapor is not in the enclosed area when a person is present. Correspondingly, for safety reasons, when the doors are opened after transport, it is necessary to leave the doors open for a sufficient amount of time to allow the carbon dioxide vapor to exit the enclosed storage area 17 before a person enters the storage area 17.
After a sufficient amount of CO 2 has been loaded into the bunker 22, the rail car, along with its frozen cargo, is ready to be moved. The amount of CO 2 used will of course depend upon the many conditions previously discussed in this specification. However, typically 9,000 pounds of CO 2 snow will keep the cargo frozen from 7 to 10 days. It is also understood that the refrigerator car, could also be charged mid trip to allow for additional CO 2 snow to be placed into the bunker.
When the bunker is first charged with CO 2 snow, the flooring strips 44 are typically warm and will act as a heat sink to assist in starting the convection flow. As the CO 2 snow sublimates, the vapor from the CO 2 will exit the mesh screen openings 30, as indicated by the arrows in FIG. 10 and proceed down the sidewall 11 through channels 34. The flow of vapor and air shown by arrows throughout the drawings, continues down the channels 34 behind the kick board 35 and proceeds through the air flow channels 44a of the nailable flooring strips 44, as shown by the arrows in FIG. 6. The air flow then continues up the channels 34 of the second sidewall 12 behind the kick plate 35 and continues up through the channels 34 until it reaches the top of the storage area where it then proceeds across the top of the ceiling to the first sidewall 11. The vapor exiting the screen 30 is the start of the strong convection current set up by the present invention. The vapor, exiting the screen 30 takes a portion of the air in the enclosed area 17 and disipates throughout the enclosed area 17 creating the BTU's for refrigeration.
The bunker 22 has insulation 24 which assists in preventing the bunker 22 from becoming a direct source of refrigerant. Instead, the refrigerating effect is obtained by the convection flow of the vapor, after the CO 2 snow has sublimated.
Other modifications of the invention will be apparent to those skilled in the art in light of the foregoing description. This description is intended to provide specific examples of individual embodiments which clearly disclose the present invention. Accordingly, the invention is not limited to these embodiments or to the use of elements having specific configurations and shapes as presented herein. All alternative modifications and variations of the present invention which follows in the spirit and broad scope of the appended claims are included. | An apparatus for a non-mechanical refrigerated vehicle is disclosed. A rail car (10) has an enclosed storage area (17). A bunker (20) is positioned proximate the ceiling (16) for containing solid refrigerant flakes. Loading manifold (50), supply manifold (70) and the nozzle (75) transfer and convert the liquid CO 2 into the solid refrigerant flakes that are directed into the bunker (22). A mesh screen (30) allows for vapor to exit the bunker (22) to the storage area (17). The screen mesh (30) is positioned proximate the first sidewall (11). The sidewalls (11) and (12) have channels (34) and the floor strips (44) have air flow channels (44e) for the flow of air, including vapor. When the refrigerant flakes sublimate in the bunker (22), the vapor flows from the bunker (22) out the screen mesh (30), down the channel (34) of the first sidewall (11), across the air flow channel ( 44e) and up the channel (34) of the second sidewall (32), all by convection. | 1 |
[0001] BACKGROUND
[0002] 1. Field of the Invention
[0003] The invention concerns a method by which a polypropylene blend is produced by processing a plastic mixture that is composed of polypropylene and other high molecular weight polymers and which is contaminated with low molecular weight polymers and other impurities. Additionally, the invention concerns a polypropylene blend with specific characteristics produced in accordance with the method.
[0004] In this case, “high molecular weight polymers” include such polymers having a molecular weight over approximately 10000, for example, polyvinyl chloride, polystyrene, polyethylene terephthalate, polypropylene and polyethylene such as, for example, LDPE (low density polyethylene), LLDPE (linear low density polyethylene), MDPE (medium density polyethylene), HDPE (high density polyethylene) UHDPE (ultra high density polyethylene) with corresponding degree of polymerization.
[0005] In contrast, “low molecular weight polymers” include such polymers having a molecular weight of up to approximately 5000, for example, waxes or other degraded high molecular weight polymers.
[0006] The plastic mixture may also contain polyester.
[0007] 2. Background of the Invention
[0008] During the introduction of the Dual System in Germany, while implementing the packaging regulation, the proper recycling of the collected plastics posed a particular challenge. An entirely new fraction, namely the plastics composites, was introduced on the market. Special recycling methods must be found for the heterogeneity and varying composition of the composite plastics. Raw material recycling is principally appropriate for this purpose. Since the plastics, within the framework of the Dual System, are collected in conjunction with a range of interfering materials, methods have been developed that reduce the separation expense to a justifiable level, but that also ensure a specific degree of purity of the plastics material. The methods described in international patent application nos. WO 96/20819 and WO 99/36180 are examples of dry process methods for the generation of composite plastic agglomerate. The method in accordance with international patent application no. WO 98/18607 is also successful when polyolefin is extracted using, among other things, sink-float separation.
[0009] After all, the objective is to separate the composite plastics into specific types of polymers and to employ them in making new products. In this regard, a method is suggested in international patent application no. WO 00/77082 A1, which was published after the priority date of the present application, by which a polyolefin plastic fraction is brought into contact with a solvent and the temperature of the solvent and, as the case may be, also the ratio of solvent to the quantity of plastic is adjusted in such a manner that as many of the polymer types as possible are dissolved. In a subsequent solid-liquid separation, one polymer type is precipitated from the solution using shearing. PP (polypropylene), LDPE (low density polyethylene), HDPE (high density polyethylene) could, in particular, be separated in conjunction with a thermal separation method, for example, in accordance with German patent application no. DE 198 06 355 A1, in which two liquid phases are produced, one of which is solvent rich and a second is polymer rich.
[0010] The content of waxes, additives, decomposition products and other impurities interferes during further recycling, particularly when these polyolefins are intended for use as new products. German patent application no. DE 100 62 437.5 which shares the same priority date, suggests a method by which the plastic mixture is introduced into an organic solvent in which at least one of the high molecular weight polymers is soluble at a specific temperature. In this case, in the presence of the employed organic solvent, the specific temperature can be defined as the dissolving temperature at which at least one of the polymers contained in the plastic mixture will be present in dissolved form by more than 10-50% by weight. In the method, the solvent at normal pressure is maintained at an operating temperature at which none of the high molecular weight polymers is dissolved and whereby a specific weight ratio of plastic mixture to solvent is adjusted. During a certain residence period, the low molecular weight components are extracted and, if necessary, the plastic mixture could then be removed from the solvent.
[0011] Each of international patent application nos. WO 96/20819, WO 99/36180, WO 98/18607 and WO 00/77082 A1 and German patent application nos. DE 198 06 355 A1 and DE 100 62 437.5 is incorporated by reference as if fully set forth herein.
SUMMARY OF THE INVENTION
[0012] Surprisingly, it was determined that products with excellent material characteristics could be generated if, initially at temperatures lower than the dissolving temperature, the plastic mixtures are freed from soluble components using solid-liquid extraction (SLE) and only afterwards are dissolved as well as subjected to subsequent separation steps. This would be particularly successful if the plastic mixture is available in pellet form.
[0013] By “pellets” is meant granulate or agglomerate which could be produced using the above mentioned dry and wet processing methods. Granulate and in particular agglomerate are characterized by high porosity or, as the case may be, by having surface fissures so that the extraction of low molecular weight polymers and other contaminants, surprisingly, is achieved with a satisfactory level of purity. Depending on the composition of the starting material, plastics blends are generated which are intended to be used together with new materials or as a replacement for new materials.
[0014] Of the plastics blends, the polypropylene blend is of particular interest.
[0015] Polypropylene is a part-crystalline material in which the crystalline share is between 50 to 70% depending on the production conditions. In this manner, isotactic, atactic and semi-tactic polypropylene is produced during propylene homopolymerization. The higher isotactic, or as the case may be, higher crystalline homopolymers can be subjected to heavy-duty mechanical pressure, are temperature stable and have low impact strength at low temperatures. The production processes may be differentiated based upon the different catalyst systems that are used for polymerization. Accordingly, a distinction is made between Ziegler-Natta and metallocene polypropylenes. Furthermore, different methods exist according to which block and random copolymers could be produced.
[0016] In Dr. Ing. Bodo Carlowitz's manual “Kunststofftabellen” [Plastics Tables], Hanser Publishing House, 4th edition, pp. 33 to 47, the common polypropylene characteristics are described. It reveals that the melt flow index MFR (measured at 230° C. with a load of 2.16 kg in accordance with ISO 1133) of the polypropylene produced in accordance with the above method, is in the range of 0.2 to 50 g/10 min.
[0017] With an increasing MFR value, the tensile strength of each polypropylene type decreases significantly so that the yield stress lies between 30 and 34 N/mm 2 for a higher isotactical homopolypropylene at a density of 0.906 to 0.910 g/cm 3 with a very high MFR value of 20 to 40 g/10 min.
[0018] The processing of polypropylene usually occurs using injection molding. To achieve faster cycle times but still maintain polypropylene injection molded parts with good constant mechanical characteristics, it is desirable to generate a polypropylene from plastic packaging materials that flows easily and which has mechanical characteristics which are as good as a polypropylene that flows less easily.
[0019] Therefore, it is the object of the invention to make available a method with which a polypropylene blend with a defined composition and a purity of more than 95% can be produced from mixed plastic packaging materials that as opposed to a new product has the advantage in the processing that it flows easily while retaining satisfactory mechanical characteristics.
[0020] These objectives are solved by the method in accordance with the invention and a polypropylene blend produced in accordance with the method of the invention.
[0021] The method in accordance with the invention is characterized by
[0022] the introduction of the plastic mixture into an organic solvent in which at least one high molecular weight polymer from the plastic mixture is soluble at a temperature specific for the polymer;
[0023] the maintaining of the solvent under normal pressure at an operating temperature at which no high molecular weight polymer is dissolved and adjusting the weight ratio of plastic waste mixture to solvent;
[0024] the extraction of low molecular weight components during a particular residence period of the plastic waste mixture in the solvent;
[0025] the dissolving of the plastic waste mixture already freed from low molecular weight components and the execution of a solid-liquid separation (SLS) for the removal of insoluble components such as paper, aluminum and other polymers depending on the type of solvent;
[0026] dissolving and phase separation, in other words, taking advantage of the presence of at least two liquid phases for the separation of different polymer compositions into fractions; and dissolving and selective precipitation of the polypropylene fraction using shearing or flow;
[0027] degassing of the polypropylene fraction; and
[0028] granulation of the polypropylene fraction for the polypropylene blend.
[0029] This sequence of steps ensures that the polypropylene is made available in the desired purity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] [0030]FIG. 1 is a schematic representation of the method in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0031] The invention is described in further detail below, as well as in the drawing and in the examples.
[0032] During the separation steps it is, for example, taken advantage of, as described in DE 198 06 355 A1, that during the dissolving of a plastic mixture in an organic solvent under certain conditions, lack of miscibility results and two liquid phases are generated which could be further treated separately. Selective precipitation can occur from a liquid phase using shearing or flow or by adding a precipitation chemical.
[0033] This separation method can be executed either alone or in combination with the liquid-liquid phase separation. As an additional separation method, a selective dissolving in solvent could be considered which could also be executed either alone or in combination with precipitation using shearing or flow or by addition of a precipitation chemical. The combination of the selective dissolving in solvent and the liquid-liquid phase separation can also be executed alone or in combination with the above described precipitation method.
[0034] In this manner, the provision for the removal of the solvent after the extraction step and the addition of fresh solvent, either chemically identical or not identical is made possible for the subsequent separation into polymer fractions.
[0035] Solvents that can be used in the method of the invention include aliphatic, aromatic or cyclical, saturated or unsaturated hydrocarbons, alcohols, carboxylic acids, amines, esters, ketones, tetrahydrofurane, bimethyl formamide, dimethyl sulphoxide, N-methyl pyrrolidone or their mixtures.
[0036] It is particularly preferable to use hexane or octane as the solvent.
[0037] Preferably, the solvent is introduced to the process, and when a critical concentration of low molecular weight polymers in the solvent has been reached, the solvent is removed and can be cleaned using distillation. It is then returned as fresh solvent for the extraction.
[0038] The concentration of plastic waste mixture in the solvent could be 10 to 20% by weight, depending on the composition of the plastic waste mixture and the type of solvent.
[0039] Preferably, the operating temperature is maintained in the area of 60° C. to 70° C. The residence time should be between 60 to 90 minutes to remove approximately 80% of the waxes.
[0040] [0040]FIG. 1 shows a schematic representation of the method execution. The composite plastics pellets, which for example consist of polypropylene and polyethylene, are introduced into the solvent, which for example could be hexane, in a certain weight ratio. When stirred, a weak relative motion of the pellets to solvent is achieved. It is preferable in the course of this that the solvent temperature will be adjusted to between 60 and 70° C., preferably 65° C. After a residence period of approximately 70 to 90 minutes, the extracted composite plastics pellets are removed, and without removing the solvent, are dissolved for further processing in a solvent vessel which also contains hexane.
[0041] Subsequently, insoluble components such as paper or aluminum and other polymers that are not soluble in hexane are removed in a decanter which operates as a filter. Then, the separation of the polymer mixture using liquid-liquid phase separation and shearing crystallization as described in WO 00/77082 occurs. Each PP, HDPE and LDPE fraction is then separately degassed in an extruder and finally formulated. The polypropylene fraction treated in this manner forms the polypropylene blend in accordance with the present invention.
EXAMPLES
Example 1
[0042] In the table below, the characteristics of a polypropylene blend produced in accordance with the invention are summarized.
PP blend produced according to method of the invention Property Standard/Procedure Average value Standard Deviation Yield stress (Mpa) ISO 527 32.8 1.8 Stretching elongation (%) ISO 527 8.3 0.8 Elongation at break (%) ISO 527 86.2 24.3 Tensile modulus of elasticity (Mpa) ISO 527 1.403 133 Impact strength 23 +/− 5° C. (kJ/m 2 ) ISO 179 3.9 0.1 Melt flow index MFR 230° C./2.16 kg (g/10 ISO 1133 16.3 7.2 min.) Melting Point (° C.) ISO 3146 163.2 1.4 Oxidation Stability (min.) DIN EN 728 12.8 6.3 Molecular weight - Mw (g/mol) GPC 234,000 34,000 - Mw/Mn (g/mol) GPC 5.5 0.8 Polymer PP content (% by weight) DSC 95.8 1.4 Polymer PE content (% by weight) DSC 4.2 1.4 Wax content (% by weight) Extraction 2.4 1.1 Calcined residue (% by weight) ISO R 1270 0.09 0.09 Chlorine content (total chlorine %) 0.01 0.00
Example 2
Comparative
[0043] A currently available method for recycling plastic packaging materials uses the beaker fraction following a float-sink separation and exclusively forms a polypropylene re-granulate that has poor characteristics compared with the new material. At a mfr 230° c/2.16 kg from 4 to 5 g/10 min., The tensile strength lies at 30 to 40 n/mm 2 .
[0044] The invention characteristics disclosed in the description above as well as in the patent claims could be significant both individually and in any chosen combination for the implementation of the invention.
[0045] The foregoing disclosure of the preferred embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of the above disclosure. The scope of the invention is to be defined only by the claims appended hereto, and by their equivalents.
[0046] Further, in describing representative embodiments of the present invention, the specification may have presented the method and/or process of the present invention as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. In addition, the claims directed to the method and/or process of the present invention should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the present invention. | A method for producing a polypropylene blend from a plastic packaging materials containing high molecular weight polypropylene, other high molecular weight polymers such as polyethylene, low molecular weight polymers and other contaminants. The method includes extraction, solid-liquid separation and liquid-liquid phase separation using various organic solvents. The polypropylene blend has a purity of 95% and has favorable melt flow characteristics, while retaining satisfactory mechanical properties. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a CIP of U.S. Ser. No. 08/951,952 filed Oct. 10, 1997 pending, which was a CIP of 08/735,361 filed Oct. 10, 1996 now abandoned.
FIELD OF INVENTION
This invention relates to a novel process for the removal of permanganate reducing compounds and alkyl iodides formed by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst. More specifically, this invention relates to a novel process for reducing and/or removing precursors of permanganate reducing compounds and alkyl iodides from intermediate streams during the formation of acetic acid by said carbonylation processes.
BACKGROUND OF THE INVENTION
Among currently employed processes for synthesizing acetic acid one of the most useful commercially is the catalyzed carbonylation of methanol with carbon monoxide as taught in U.S. Pat. No. 3,769,329 issued to Paulik et al on Oct. 30, 1973. The carbonylation catalyst comprises rhodium, either dissolved or otherwise dispersed in a liquid reaction medium or else supported on an inert solid, along with a halogen containing catalyst promoter as exemplified by methyl iodide. The rhodium can be introduced into the reaction system in any of many forms, and it is not relevant, if indeed it is possible, to identify the exact nature of the rhodium moiety within the active catalyst complex. Likewise, the nature of the halide promoter is not critical. The patentees disclose a very large number of suitable promoters, most of which are organic iodides. Most typically and usefully, the reaction is conducted with the catalyst being dissolved in a liquid reaction medium through which carbon monoxide gas is continuously bubbled.
An improvement in the prior art process for the carbonylation of an alcohol to produce the carboxylic acid having one carbon atom more than the alcohol in the presence of a rhodium catalyst is disclosed in commonly assigned U.S. Pat. Nos. 5,001,259, issued Mar. 19, 1991; 5,026,908, issued Jun. 25, 1991 and 5,144,068, issued Sep. 1, 1992 and European patent 161,874 B2, published Jul. 1, 1992. As disclosed therein acetic acid is produced from methanol in a reaction medium comprising methyl acetate, methyl halide, especially methyl iodide, and rhodium present in a catalytically effective concentration. The invention therein resides primarily in the discovery that catalyst stability and the productivity of the carbonylation reactor can be maintained at surprisingly high levels, even at very low water concentrations, i.e. 4 weight (wt) % or less, in the reaction medium (despite the general industrial practice of maintaining approximately 14 wt % or 15 wt % water) by maintaining in the reaction medium, along with a catalytically effective amount of rhodium, at least a finite concentration of water, methyl acetate and methyl iodide, a specified concentration of iodide ions over and above the iodide content which is present as methyl iodide or other organic iodide. The iodide ion is present as a simple salt, with lithium iodide being preferred. The patents teach that the concentration of methyl acetate and iodide salts are significant parameters in affecting the rate of carbonylation of methanol to produce acetic acid especially at low reactor water concentrations. By using relatively high concentrations of the methyl acetate and iodide salt, one obtains a surprising degree of catalyst stability and reactor productivity even when the liquid reaction medium contains water in concentrations as low as about 0.1 wt %, so low that it can broadly be defined simply as “a finite concentration” of water. Furthermore, the reaction medium employed improves the stability of the rhodium catalyst, i.e. resistance to catalyst precipitation, especially during the product recovery steps of the process wherein distillation for the purpose of recovering the acetic acid product tends to remove from the catalyst the carbon monoxide which in the environment maintained in the reaction vessel, is a ligand with stabilizing effect on the rhodium. U.S. Pat. Nos. 5,001,259, 5,026,908 and 5,144,068 are herein incorporated by reference.
It has been found that a low water carbonylation process for the production of acetic acid reduces such by-products as carbon dioxide, hydrogen, and propionic acid. However, the amount of other impurities, present generally in trace amounts, is also increased, and the quality of acetic acid sometimes suffers when attempts are made to increase the production rate by improving catalysts, or modifying reaction conditions.
These trace impurities affect quality of acetic acid, especially when they are recirculated through the reaction process. Among the impurities, which decrease the permanganate time of the acetic acid, are carbonyl compounds, and unsaturated carbonyl compounds. As used herein, the phrase “carbonyl” is intended to mean compounds which contain aldehyde or ketone functional groups which compounds may or may not possess unsaturation. See Catalysis of Organic Reaction , 75, 369-380 (1998), for further discussion on impurities in a carbonylation reaction system.
The present invention is directed to reduction and/or removal of permanganate reducing compounds (PRC's) such as acetaldehyde, acetone, methyl ethyl ketone, butyraldehyde, crotonaldehyde, 2-ethyl crotonaldehyde, and 2-ethyl butyraldehyde and the like, and the aldol condensation products thereof. It also leads to reduction of propionic acid. Reduction of other impurities include alkyl iodides such as ethyl iodide, propyl iodide, butyl iodide, pentyl iodide, hexyl iodide, and the like.
It is desirable to remove alkyl iodides from the reaction product since traces of these impurities (in the acetic acid product) tend to poison the catalyst used in the production of vinyl acetate, the product most commonly produced from acetic acid. The present invention is thus also directed to removal of alkyl iodides, in particular C 2-12 alkyl iodide compounds. The carbonyl impurities may further react with iodide catalyst promoters to form multi-carbon alkyl iodides, e.g., ethyl iodide, butyl iodide, hexyl iodide and the like. Since many impurities originate with acetaldehyde, it is therefore a primary objective to remove or reduce the acetaldehyde and alkyl iodide content in the reaction system.
Conventional techniques to remove impurities include treatment of acetic acid with oxidizers, ozone, water, methanol, activated-carbon, amines, and the like, which treatment may or may not be combined with distillation of the acetic acid. The most typical purification treatment involves a series of distillations of the final product. It is known to remove carbonyl impurities from organic streams by treating the organic streams with an amine compound such as hydroxylamine which reacts with the carbonyl compounds to form oximes followed by distillation to separate the purified organic product from the oxime reaction products. However, the additional treatment of the final product adds cost to the process and it has been found that distillation of the treated acetic acid product can result in additional impurities being formed.
While it is possible to obtain acetic acid of relatively high purity, the acetic acid product formed by the above described low water carbonylation process and purification treatment, frequently remains deficient with respect to the permanganate time. This is due to the presence therein of small proportions of residual impurities. Since a sufficient permanganate time is an important commercial test, which the acid product must meet for many uses, the presence therein of such impurities that decrease permanganate time is objectionable. The removal of minute quantities of these impurities from the acetic acid by conventional treatment and distillation techniques is not economically or commercially feasible by distillation since the impurities have boiling points close to that of the acetic acid product.
It is important to determine where in the carbonylation process impurities can be removed. It is also important to determine by what economically viable process impurities can be removed without risk of further contamination to the final product or unnecessary added costs. JP patent application 5-169205 discloses a method for manufacture of high purity acetic acid by adjusting the acetaldehyde concentration of the reaction solution below 1500 ppm. By maintaining the acetaldehyde concentration in the reaction solution below 1500 ppm, it is stated that it is possible to suppress the formation of impurities and manufacture high purity acetic acid by performing only basic distillation operations during purification of the crude acetic acid formed.
EP 487,284, B1, published Apr. 12, 1995, states that carbonyl impurities present in the acetic acid product generally concentrate in the overhead from the light ends column. Accordingly, the light ends column overhead is treated with an amine compound i.e., hydroxylamine which reacts with the carbonyl compounds to allow such carbonyls to be separated from the remaining overhead by distillation, resulting in an acetic acid product which has improved permanganate time.
EP 0 687 662 A2 describes a process for producing high purity acetic acid whereby an acetaldehyde concentration of 400 ppm or less is maintained in the reactor by removal thereof using a single or multi-stage distillation process. Streams suggested for processing to remove acetaldehyde include a light phase comprising primarily water, acetic acid and methyl acetate; a heavy phase comprising primarily methyl iodide, methyl acetate and acetic acid; an overhead stream comprising primarily methyl iodide and methyl acetate; or a recirculating stream comprising the light and heavy phase combined. Although four streams are suggested for processing, the reference teaches and exemplifies use of the heavy phase. No teaching or suggestion is given regarding which stream(s) possesses the greatest concentration of acetaldehyde.
Also disclosed in EP'662 is management of reaction conditions to control the formation of acetaldehyde in the reactor. By controlling the formation of acetaldehyde, it is stated that reduction of by-products such as crotonaldehyde, 2-ethylcrotonaldehyde, and alkyl iodides are reduced. However, it is pointed out that management of reaction conditions “have a defect to increase a by-production speed of propionic acid.” indicating that propionic acid is a problem with the disclosed process of '662.
Hence, EP'662 describes optimization of reaction conditions to avoid formation of acetaldehyde as well as removal of any acetaldehyde beyond a level of 400 ppm formed in the reactor.
While the above-described processes have been successful in removing carbonyl impurities from the carbonylation system and for the most part controlling acetaldehyde levels and permanganate time problems in the final acetic acid product, further improvements can still be made. There remains a need to determine where in the carbonylation process the permanganate reducing compounds, and in particular, acetaldehyde and alkyl iodides are most concentrated and therefore can be reduced or removed so as to insure consistent purity of product. At the same time, there remains a need to provide a process for reduction/removal of such carbonyl materials and iodide compounds without sacrificing the productivity of the carbonylation process or without incurring substantial additional operating costs.
SUMMARY OF THE INVENTION
It has now been discovered that a light ends phase from the light ends distillation column contains carbonyl-containing permanganate reducing compounds, and in particular acetaldehyde which may be further concentrated and removed from the process. In one aspect of this invention, the light ends phase is distilled twice, once through a distillation column which serves to separate the acetaldehyde, methyl iodide, and methyl acetate from acetic acid and water. The second distillation column serves to separate acetaldehyde from methyl iodide and methyl acetate and essentially serves to concentrate and purge the acetaldehyde from the process. Optionally, in another aspect of the invention, the resulting distillate from the second distillation is directed to an extractor to separate out concentrated acetaldehyde and return a residual saturated organic iodide solution to the carbonylation reaction system.
In another aspect of the invention, alkyl iodide compounds, in particular C 2-12 , may be removed or significantly reduced employing the described dual distillation process.
It has been found that when shutting down the carbonylation system, in particular the distillation columns employed in the present process, polymers of acetaldehyde, in particular higher molecular weight polymers tend to form and build up in the base of the second column. Another aspect of the present invention describes a method to deal with this problem. It has been found that a constant flow of solvent to maintain contact between the stream within the second distillation column and a solvent from an internal stream (such as one that contains a large percentage of acetic acid or methyl acetate) results in a polymer-free column base upon shut down of the unit. By having the base devoid of polymer build up, one may shut down and subsequently start up the column in a relatively trouble free, efficient, and cost-effective manner.
The present invention utilizes a light phase, which is an internal, intermediate stream in the process, instead of a heavy phase (as suggested in EP'662), for reduction, or removal of PRC's, their precursors and alkyl iodide compounds. The art traditionally employs a heavy phase for treatment or removal of carbonyl impurities and in particular, removal of acetaldehyde. To date, the art was not aware-that light phase was the better option compared to the heavy phase to reduce PRC's and alkyl iodides. Generally, the art employs an extractor before the second distillation; it has been found that the use of an extractor after the second distillation (or a post-extractor process) results in greater removal of acetaldehyde. It has also been found that due to the dual distillation process, coupled with the post extractor, a very concentrated acetaldehyde stream with essentially no methyl iodide is purged from the process. It has been found that the formation of meta- and paraldehyde in the second column, as well as higher molecular weight polymers thereof, can be inhibited or suppressed by the use of an internal stream comprising approximately 70 wt % water and 30 wt % acetic acid. Because the stream is internal, to the process, it does not place an added water load to the process. It has further been found that the recycle of the first column's residue to the light ends column decanter can be used to extract more PRC's from the heavy phase into the light phase and thus improve acetic acid product quality overall.
A preferred embodiment of the present invention is directed towards a process for reduction and/or removal of permanganate reducing compounds, their precursors, and C 2-12 alkyl iodide compounds formed in the carbonylation of methanol to a product of acetic acid, wherein said methanol is carbonylated in a suitable liquid phase reaction medium comprising a Group VIII metal catalyst, an organic iodide and iodide salt catalyst promoter; the products of said carbonylation are separated into a volatile phase comprising product, and a less volatile phase comprising Group VIII metal catalyst, acetic acid, and iodide catalyst promoter; said product phase distilled in a distillation tower to yield a purified product and an overhead comprising organic iodide, methyl acetate, water, acetic acid, and unreacted methanol, directing at least a portion of the overhead to an overhead receiver decanter which separates the overhead into a light phase, comprising acetic acid and water, and a heavy phase comprising methyl acetate and organic iodide; and recycling the heavy phase to the carbonylation reactor, the improvement which comprises
(a) directing the light phase comprising acetic acid and water to a distiller which separates the mixture into two streams: residue stream ( 1 ) comprising primarily water and acetic acid, and overhead stream 2 ) comprising methyl iodide, methyl acetate, methanol, C 2-12 alkyl iodides, and permanganate reducing compounds(PRC's);
(b) circulating stream ( 1 ) of step (a) to further processing and ultimately back to the reaction system, and stream ( 2 ) of step (a) to a second distiller which serves to strip the PRC's and alkyl iodides from the mixture;
(c) optionally, forwarding the over head stream containing PRC's or precursors thereof of step (b) to an extractor and,
(d) separating out concentrated PRC's and alkyl iodides for disposal and returning the organic iodide phase of (b) or (c) as a stream containing a lower percentage of PRC's, precursors, and/or C 2-12 alkyl iodides to the carbonylation reaction system.
The bulk of the overhead from the light phase is recycled to the reactor. Thus, in accordance with the present invention, the inventory of PRC's including acetaldehyde, and alkyl iodides is greatly reduced by this multiple distillation plus optional post extraction process and, at the same time, accomplishing such product quality without substantially increasing the cost of production.
It has been found that PRC's, in particular acetaldehyde, crotonaldehyde, and 2-ethyl crotonaldehyde, and alkyl iodides, in particular hexyl iodide, are reduced by at least 50%, usually greater than that, employing the inventive process. Additionally, propionic acid has been reduced, usually greater than 20%, most often greater than 30% and 40%, and total iodides have been reduced by a percentage reduction of about 50%, most often greater than 60%. The permanganate time has been observed to increase by a percentage of about 50%, usually greater than 70% with the inventive process.
Once the inventive process was operational and shut down of the system was on going, it was discovered that polymers of acetaldehyde, in particular, polymers having a molecular weight greater than about 1000, tended to build up in the second column and plug the column. The polymers were found to be viscous, and thixotropic and tended to adhere to the walls of the column. Upon heating, these polymers tended to crystallize and harden along the walls of the column, making them very difficult to remove. It was found that this problem could be avoided by contacting the stream flowing through the second distillation column with solvent stream flow in an amount sufficient and at a flow rate sufficient to avoid aldol condensation polymer formation or to avoid formation of polymers of acetaldehyde. The solvent may be selected from acetic acid, methyl acetate, methanol, water, methyl iodide and the like or combinations thereof with acetic acid being preferred in view of the abundance of an internal stream to utilize. Generally, amounts sufficient to avoid aldol condensation reactions from occurring are rates of about 0.25-5 gallon per minute (gpm), preferably about 0.5-2 gpm with most preferable rate being about 1 gpm. It is undesirable to use an excess of solvent since this places a greater load on the system to reprocess the excess solvent. Although various positions of ingress of the solvent are acceptable, it is preferred that the solvent be contacted with the stream in the second distillation column at the base of the column.
DRAWINGS
FIG. 1 illustrates a preferred embodiment for the removal of carbonyl impurities from an intermediate stream of the carbonylation process for the production of acetic acid by a carbonylation reaction.
DETAILED DESCRIPTION OF THE INVENTION
The purification process of the present invention is useful in any process used to carbonylate methanol to acetic acid in the presence of a Group VIII metal catalyst such as rhodium and an iodide promoter. A particularly useful process is the low water rhodium catalyzed carbonylation of methanol to acetic acid as exemplified in aforementioned U.S. Pat. No. 5,001,259. Generally, the rhodium component of the catalyst system is believed to be present in the form of a coordination compound of rhodium with a halogen component providing at least one of the ligands of such coordination compound. In addition to the coordination of rhodium and halogen, it is also believed that carbon monoxide coordinates with rhodium. The rhodium component of the catalyst system may be provided by introducing into the reaction zone rhodium in the form of rhodium metal, rhodium salts such as the oxides, acetates, iodides, etc., or other coordination compounds of rhodium, and the like.
The halogen-promoting component of the catalyst system consists of a halogen compound comprising an organic halide. Thus, alkyl, aryl, and substituted alkyl or aryl halides can be used. Preferably, the halide promoter is present in the form of an alkyl halide in which the alkyl radical corresponds to the alkyl radical of the feed alcohol, which is carbonylated. Thus, in the carbonylation of methanol to acetic acid, the halide promoter will comprise methyl halide, and more preferably methyl iodide.
The liquid reaction medium employed may include any solvent compatible with the catalyst system and may include pure alcohols, or mixtures of the alcohol feedstock and/or the desired carboxylic acid and/or esters of these two compounds. The preferred solvent and liquid reaction medium for the low water carbonylation process comprises the carboxylic acid product. Thus, in the carbonylation of methanol to acetic acid, the preferred solvent is acetic acid.
Water is contained in the reaction medium but at concentrations well below that which has heretofore been thought practical for achieving sufficient reaction rates. It has previously been taught that in rhodium catalyzed carbonylation reactions of the type set forth in this invention, the addition of water exerts a beneficial effect upon the reaction rate (U.S. Pat. No. 3,769,329). Thus most commercial operations run at water concentrations of at least about 14 wt %. Accordingly, it is quite unexpected that reaction rates substantially equal to and above reaction rates obtained with such high levels of water concentration can be achieved with water concentrations below 14 wt % and as low as about 0.1 wt %.
In accordance with the carbonylation process most useful to manufacture acetic acid according to the present invention, the desired reaction rates are obtained even at low water concentrations by including in the reaction medium methyl acetate and an additional iodide ion which is over and above the iodide which is present as a catalyst promoter such as methyl iodide or other organic iodide. The additional iodide promoter is an iodide salt, with lithium iodide being preferred. It has been found that under low water concentrations, methyl acetate and lithium iodide act as rate promoters only when relatively high concentrations of each of these components are present and that the promotion is higher when both of these components are present simultaneously (U.S. Pat. No. 5,001,259). The concentration of lithium iodide used in the reaction medium of the preferred carbonylation reaction system is believed to be quite high as compared with what little prior art there is dealing with the use of halide salts in reaction systems of this sort. The absolute concentration of iodide ion content is not a limitation on the usefulness of the present invention.
The carbonylation reaction of methanol to acetic acid product may be carried out by contacting the methanol feed, which is in the liquid phase, with gaseous carbon monoxide bubbled through a liquid acetic acid solvent reaction medium containing the rhodium catalyst, methyl iodide promoter, methyl acetate, and additional soluble iodide salt, at conditions of temperature and pressure suitable to form the carbonylation product. It will be generally recognized that it is the concentration of iodide ion in the catalyst system that is important and not the cation associated with the iodide, and that at a given molar concentration of iodide the nature of the cation is not as significant as the effect of the iodide concentration. Any metal iodide salt, or any iodide salt of any organic cation, or quaternary cation such as a quaternary amine or phosphine or inorganic cation can be used provided that the salt is sufficiently soluble in the reaction medium to provide the desired level of the iodide. When the iodide is added as a metal salt, preferably it is an iodide salt of a member of the group consisting of the metals of Group IA and Group IIA of the periodic table as set forth in the “Handbook of Chemistry and Physics” published by CRC Press, Cleveland, Ohio, 1975-76 (56th edition). In particular, alkali metal iodides are useful, with lithium iodide being preferred. In the low water carbonylation process most useful in this invention, the additional iodide over and above the organic iodide promoter is present in the catalyst solution in amounts of from about 2 to about 20 wt %, the methyl acetate is present in amounts of from about 0.5 to about 30 wt %, and the lithium iodide is present in amounts of from about 5 to about 20 wt %. The rhodium catalyst is present in amounts of from about 200 to about 2000 parts per million (ppm).
Typical reaction temperatures for carbonylation will be approximately 150 to about 250° C., with the temperature range of about 180 to about 220° C. being the preferred range. The carbon monoxide partial pressure in the reactor can vary widely but is typically about 2 to about 30 atmospheres, and preferably, about 3 to about 10 atmospheres. Because of the partial pressure of by-products and the vapor pressure of the contained liquids, the total reactor pressure will range from about 15 to about 40 atmospheres.
A typical reaction and acetic acid recovery system which is used for the iodide-promoted rhodium catalyzed carbonylation of methanol to acetic acid is shown in FIG. 1 and comprises a liquid phase carbonylation reactor, flasher, and a methyl iodide acetic acid light ends column 14 which has an acetic acid side stream 17 which proceeds to further purification. The reactor and flasher are not shown in FIG. 1 . These are considered standard equipment now well known in the carbonylation process art. The carbonylation reactor is typically a stirred vessel within which the reacting liquid contents are maintained automatically at a constant level. Into this reactor there are continuously introduced fresh methanol, carbon monoxide, sufficient water as needed to maintain at least a finite concentration of water in the reaction medium, recycled catalyst solution from the flasher base, a recycled methyl iodide and methyl acetate phase, and a recycled aqueous acetic acid phase from an overhead receiver decanter of the methyl iodide acetic acid light ends or splitter column 14 . Distillation systems are employed that provide means for recovering the crude acetic acid and recycling catalyst solution, methyl iodide, and methyl acetate to the reactor. In a preferred process, carbon monoxide is continuously introduced into the carbonylation reactor just below the agitator, which is used to stir the contents. The gaseous feed is thoroughly dispersed through the reacting liquid by this stirring means. A gaseous purge stream is vented from the reactor to prevent buildup of gaseous by-products and to maintain a set carbon monoxide partial pressure at a given total reactor pressure. The temperature of the reactor is controlled and the carbon monoxide feed is introduced at a rate sufficient to maintain the desired total reactor pressure.
Liquid product is drawn off from the carbonylation reactor at a rate sufficient to maintain a constant level therein and is introduced to the flasher. In the flasher the catalyst solution is withdrawn as a base stream (predominantly acetic acid containing the rhodium and the iodide salt along with lesser quantities of methyl acetate, methyl iodide, and water), while the vapor overhead stream of the flasher comprises largely the product acetic acid along with methyl iodide, methyl acetate, and water. Dissolved gases exiting the reactor as a side stream and entering the flasher consist of a portion of the carbon monoxide along with gaseous by products such as methane, hydrogen, and carbon dioxide and exit the flasher as an overhead stream and are directed to the light ends or splitter column 14 as stream 26 .
It has now been discovered that there is a higher concentration, about 3 times, of the PRC's and in particular acetaldehyde content in the light phase than in the heavy phase stream-exiting column 14 . Thus, in accordance with the present invention, stream 28 , comprising PRC's is directed to an overhead receiver decanter 16 where the light ends phase, stream 30 , is directed to distillation column 18 .
The present invention may broadly be considered as distilling PRC's, primarily aldehydes and alkyl iodides, from a vapor phase acetic acid stream. The vapor phase stream is twice distilled and optionally post extracted to remove PRC's. Disclosed is a method of removing aldehydes and alkyl iodides and reducing levels of propionic acid, from a first vapor phase acetic acid stream comprising:
a) condensing said first vapor phase acetic acid stream in a first condenser and biphasically separating it to form a first heavy liquid phase product and a first light liquid phase product wherein said first heavy liquid phase contains the larger proportion of catalytic components than said first light liquid phase product;
b) distilling said light liquid phase product in a first distillation column, which distillation is operative to form a second vapor phase acetic acid product stream which is enriched with aldehydes and alkyl iodides with respect to said first vapor phase acetic acid stream;
c) condensing said second vapor phase stream in a second condenser and biphasically separating it to form a second heavy liquid phase product and a second light liquid phase product wherein said second heavy liquid phase product contains a higher proportion of catalytic components than said second light liquid phase product; and
d) distilling said second light liquid phase product in a second distillation column wherein said process is operative to reduce and/or remove at least 50% of the alkyl iodide and aldehyde impurities and at least 20% of the propionic acid impurities in said first vapor phase acetic acid stream in an aldehyde and alkyl iodide waste stream.
Referring to FIG. 1, the first vapor phase acetic acid stream ( 28 ) comprises methyl iodide, methyl acetate, acetaldehyde and other carbonyl components. This stream is then condensed and separated (in vessel 16 ) to form a first vapor phase stream to separate the heavy phase product containing the larger proportion of catalytic components—which is recirculated to the reactor (not shown in FIG. 1 ), and a light phase ( 30 ) comprising acetaldehyde, water, and acetic acid. This light phase is subsequently distilled twice to remove the PRC's and primarily the acetaldehyde component of the stream. The light phase ( 30 ) is directed to column 18 , which serves to form a second vapor phase ( 36 ) enriched in aldehydes and alkyl iodides with respect to stream 28 . Steam 36 is condensed (vessel 20 ) and biphasically separated to form a second heavy liquid phase product and a second light phase liquid product. This second heavy liquid phase contains a higher proportion of catalytic components than the second light liquid phase and is subsequently recirculated to the reactor. The second liquid light phase ( 40 ) comprising acetaldehyde, methyl iodide, methanol, and methyl acetate is directed to a second distillation column ( 22 ) wherein the acetaldehyde is separated from the other components. Catalytic components include methyl iodide, methyl acetate, methanol, and water. This inventive process has been found to reduce and/or remove at least 50% of the alkyl iodide impurities found in an acetic acid stream. It has also been shown that acetaldehyde and its derivatives is reduced and/or removed by at least 50%, most often greater than 60%.
A preferred embodiment of the present invention is shown in FIG. 1; from the top of the light ends or splitter column, 14 , vapors are removed via stream 28 , condensed, and directed to 16 . The vapors are chilled to a temperature sufficient to condense and separate the condensable methyl iodide, methyl acetate, acetaldehyde and other carbonyl components, and water into two phases. The light phase is directed to distillation column 18 . Column 18 serves to concentrate the acetaldehyde in stream 32 . A portion of stream 30 , as stream 34 is directed back to the light ends column, 14 , as reflux. A portion of stream 28 comprises noncondensable gases such as carbon dioxide, hydrogen, and the like and can be vented as shown in stream 29 on FIG. 1 . Not illustrated in FIG. 1, leaving overhead receiver decanter 16 is also the heavy phase of stream 28 . Ordinarily this heavy phase is recirculated to the reactor. However, in another aspect of the invention, a slip stream, generally a small amount, e.g., 25 vol. %, preferably less than about 20 vol. % of the heavy phase is directed to a carbonyl treatment process of this invention and the remainder recycled to the reactor or reaction system. This slip stream of the heavy phase may be treated individually, or combined with the light phase, stream 30 for further distillation and extraction of carbonyl impurities.
Stream 30 enters column 18 as stream 32 in about the middle of the column. Column 18 serves to concentrate the aldehyde components of stream 32 by separating water and acetic acid from the lighter components. In a preferred process of the present invention, stream 32 is distilled in 18 , where 18 contains approximately 40 trays, and temperature ranges therein from about 283° F. (139.4° C.) at the bottom to about 191° F. (88.3° C.) at the top of the column. Exiting the top of 18 is stream 36 comprising PRC's and in particular acetaldehyde, methyl iodide, methyl acetate, and methanol, and alkyl iodides. Exiting the bottom of 18 is stream 38 comprising approximately 70% water and 30% acetic acid. Stream 38 is processed, generally cooled utilizing a heat exchanger, is recycled to the light ends column overhead decanter 16 and ultimately to the reactor or reaction system. Stream 36 has been found to have approximately seven times more aldehyde content after the recycle through decanter 16 . It has been found that recycling a portion of stream 38 identified as stream 46 back through 16 increases efficiency of the inventive process and allows for more acetaldehyde to be present in the light phase, stream 32 . Stream 36 is then directed to an overhead receiver 20 after it has been chilled to condense any condensable gases present.
Exiting 20 is stream 40 comprising acetaldehyde, methyl iodide, methyl acetate, and methanol. A portion of stream 40 , i.e., side stream 42 is returned to 18 as reflux. Stream 40 enters distillation column 22 at about the bottom of the column. Column 22 serves to separate the majority of acetaldehyde from the methyl iodide, methyl acetate, and methanol in the stream 40 . In an embodiment, column 22 contains about 100 trays and is operated at a temperature ranging from about 224° F. (106.6° C.) at the bottom to about 175° F. (79.4° C.) at the top. In an alternate embodiment, 22 contain structured packing, in place of trays. Preferred packing is a structured packing with an interfacial area of about 65 ft 2 /ft 3 , preferably made from a metallic alloy like 2205 or other like packing material, provided they are compatible with the compositions. It was observed during experimentation that uniform column loading, required for good separation, were better with structured packing than with trays. Alternatively, ceramic packing may be employed. The residue of 22 , stream 44 , exits at the bottom of the tower and is recycled to the carbonylation process.
Acetaldehyde polymerizes in the presence of methyl iodide to form metaldehyde and paraldehyde. These polymers generally are low molecular weight, less than about 200. Paraldehyde has been found to be relatively soluble in the reaction liquid, and primarily in acetic acid. Metaldehyde, upon its precipitation, is a sand-like, granule polymer that is not soluble in the reaction liquid beyond about 3 wt % concentration. Although these polymers are a nuisance for the reaction system, they generally do not require great efforts to remove from the tower once formed.
It has been discovered that during the reaction, and with the heating of column 22 , higher molecular weight polymers of acetaldehyde, molecuar weight greater than about 1000, form. These higher molecular weight polymers are believe to come as results of processing the light phase. No literature has been found of formation of these polymers when processing the heavy phase. There has been no indication that these higher molecular weight polymers form when processing the heavy phase. This is a unique problem to processing of the light phase. The higher molecular weight polymers are viscous and thixotropic or do not obey Newtonian fluid laws. As heat is applied to the system, they tend to harden and adhere to the walls of the tower where their removal is cumbersome. Once polymerized they are only slightly soluble in organic or aqueous solvents and removal from the system requires mechanical means. Thus an inhibitor is needed, preferably in tower 22 , to reduce the formation of these impurities, i.e., metaldehyde and paraldehyde and higher molecular weight polymers of acetaldehyde (AcH). Inhibitors generally consist of C 1-10 alkanol, preferably methanol, water, acetic acid and the like used individually or in combination with each other or with one or more other inhibitors. Stream 46 , which is a portion of column 18 residue and a slip stream of stream 38 , comprises water and acetic acid and hence can serve as an inhibitor. Stream 46 as shown in FIG. 1 splits to form streams 48 and 50 . Stream 50 is added to column 22 to inhibit formation of metaldehyde and paraldehyde impurities and higher molecular weight polymers. Since the residue of 22 is recycled to the reactor, any inhibitors added must be compatible with the reaction chemistry. It has been found that small amounts of water, methanol, acetic acid, or a combination thereof, do not interfere with the reaction chemistry and practically eliminate the formation of polymers of acetaldehyde. Stream 50 is also preferably employed as an inhibitor since this material does not change the reactor water balance. Water as an inhibitor is the least preferred solvent of inhibition since large quantities are generally needed to be an effective inhibitor and as such it tends to extract a large amount of acetaldehyde, reducing the purity of stream 52 exiting column 22 .
Exiting the top of 22 is stream 52 comprising PRC's. Stream 52 is directed to a condenser and then to overhead receiver 24 . After condensation, any non-condensable materials are vented from receiver 24 . Exiting 24 is stream 54 . Stream 56 , a slip stream of stream 54 , is used as reflux for 22 . Exiting the bottom of 22 is stream 44 comprising methyl iodide, methanol, methyl acetate, methanol and water. This stream is combined with stream 66 and directed to the reactor.
It is important for the extraction mechanism that the top stream of 22 remain cold, generally at a temperature of about 13° C. This stream may be obtained or maintained at about 13° C. by conventional techniques known to those of skill in the art, or any mechanism generally accepted by the industry.
In a preferred embodiment of the present invention, upon exiting 24 , stream 54 / 58 is sent through a condenser/chiller (now stream 62 ) and then to the extractor 27 to remove and recycle small amounts of methyl iodide from the aqueous PRC stream. Non-condensable gases are vented from the top of 24 . In extractor 27 , PRC's and alkyl iodides are extracted with water, preferably water from an internal stream so as to maintain water balance within the reaction system. As a result of this extraction, methyl iodide separates from the aqueous PRC's and alkyl iodide phase. In a preferred embodiment, a mixer-settler with a water-to-feed ratio of about 2 is employed.
Exiting the extractor is stream 66 comprising methyl iodide, which is recycled to the reaction system and ultimately to the reactor. The aqueous stream of 64 , leaves the extractor from the top thereof. This PRC-rich, and in particular, acetaldehyderich aqueous phase is directed to waste treatment.
The PRC ( 52 ) and alkyl iodide-rich phase ( 44 ) of the stream stripped from the light phase may optionally be directed to an extractor ( 27 ) to remove organic iodide compounds therefrom. The present inventive process has been found to isolate methyl iodide from acetaldehyde for recycling back to the reaction system. Additionally, alkyl iodides such as hexyl iodide have been reduced in the final acetic acid process significantly via the dual distillation process disclosed herein. Hexyl iodide has been reduced by a percent reduction of about 50%, usually greater than 70%. Furthermore, impurities such as crotonaldehyde, 2-ethyl crotonaldehyde were found to be significantly reduced or removed completely from the process. Crotonaldehyde and ethyl crotonaldehyde have been found reduced and/or removed by at least 50%, most often greater than 75% and sometimes 100%. Propionic acid concentration has been found reduced and/or removed by a percent reduction of at least 20%, usually greater than about 30 or 40% when compared to the initial stream removed from vessel 14 (without processing). Total iodides were found reduced by a percent reduction of at least 50%, usually greater than about 60%.
The permanganate time found for the acetic acid product stream once processed through the disclosed method increased about 8-fold, or from about 50%, to greater than 75% or 85% from that product stream not processed as herein described. Data indicates a 50 and 35 second time to increase to about 6 and 5 minutes respectively.
Although the present invention has been generally described above utilizing the light ends phase of column 14 , any stream in the carbonylation process having a high concentration of PRC's and alkyl iodides may be treated in accordance with the present invention.
Illustrative alternate embodiments of the present invention, not shown in FIG. 1 include but are not limited to the following:
a) directing an overhead steam from vessel 16 comprising light phase organic material to column 18 and proceeding as described above;
b) directing a residue stream comprising heavy phase organic material from vessel 16 to column 18 and proceeding as described above;
c) directing a stream, preferably a residue stream, from a light ends receiver vent decanter using stream 29 , and proceeding as described above;
d) directing a stream from the light ends vent stripper column and proceeding as described above;
e) any combination of the above streams (a-d) which comprise a high concentration of PRC's, propionic acid and alkyl iodide impurities.
Optimization of the inventive process when employing alternate streams may require modification of equipment to achieve maximum efficiency of PRC's and alkyl iodide removal from the carbonylation process. For example, if the same equipment is employed for alternate streams, as for the preferred stream described (i.e. use of stream 28 ), a taller distillation column 18 may be required to achieve maximum efficiency of removal. If one employs a stream comprising heavy phase components in the inventive process, removal of acetaldehyde may not be as efficient compared to removal of acetaldehyde strictly from a light phase stream.
As previously mentioned, it has been found that when shutting down the carbonylation system, in particular the distillation columns employed in the present process, polymers of acetaldehyde, both low and high molecular weight chain polymers, tend to form and build up in the base of the second column. This is due to the reaction of acetaldehyde and HI present in the column and has been seen to react when the temperature is about 102° C. A constant flow of solvent to maintain contact between the stream within the second distillation column and a solvent from an internal stream (such as one that contains a large percentage of acetic acid or methyl acetate) results in a polymer-free column base during shut down of the column or the PRC/alkyl iodide removal process.
Preferred solvents include those from internal streams containing primarily acetic acid, methyl acetate, methanol, water, methyl acetate, methyl iodide, or combinations thereof. To maintain internal balance within the system, it is preferred to utilize an internal stream, however solvent from an external source may be employed. Since acetic acid is high boiling, it helps strip the acetaldehyde overhead. However, any non-reactant solvent with a normal boiling point greater than or equal to the boiling point of methyl iodide is acceptable. This solvent could be recovered by sending the residue to a recovery device (e.g., stripper, decanter, or permeable membrane).
Overall benefits observed to the final product utilizing the above described process include:
1. increased pernanganate time test values.
2. lower concentration of PRC's;
3. lower total iodides; and,
4. lower propionic acid.
The following Table 1 illustrates data for various PRC's and permanganate time before and after the inventive process was employed. The data was obtained from a crude reactor product stream, and a crude acetic acid product residue stream once the reactor was operating at steady state conditions.
TABLE 1
Data from Reactor Product and Residue Product Stream under Reactor
Operating at Steady State Conditions.
PRC
Before Process
After Process
Acetaldehyde
1480
ppm
596
ppm
Crotonaldehyde (res)
8
ppm
0
2-ethyl crotonaldehyde (res)
7
ppm
0
Ethyl iodide
622
ppm
245
ppm
Hexyl iodide (res)
140
ppb
22
ppb
250
ppb
30
ppb
Total iodide (res)
225
ppb
100
ppb
Propionic acid (res)
250
ppm
150; 130
ppm
Permanganate time (res)
50
seconds
6
min
35
seconds
5
min
res = residue | Disclosed is a method to manufacture high purity acetic acid. Although described in relation to that produced by a low water carbonylation process the present invention is applicable to other mechanisms for production of acetic acid which results in formation of permanganate reducing compounds such as acetaldehyde and its derivatives, and alkyl iodide impurities in intermediate process streams. It has been found that permanganate reducing compounds and alkyl iodides may be conveniently removed from a light phase of an intermediate stream in the reaction process by employing a multiple distillation process coupled with an optional post extraction of acetaldehyde. The distillation process involves first distilling a light phase to concentrate the permanganate reducing compounds, and in particular the acetaldehyde, and then separating the permanganate reducing compounds and alkyl iodides in a second distillation tower. The second distillation serves to remove the permanganate reducing compounds and alkyl iodides from methyl iodide, methyl acetate, and methanol mixture. As an optional third step, the twice distilled stream may be directed to an extractor to recover any remaining quantities of methyl iodide from the aqueous acetaldehyde waste stream. This process affords a final product in greater than 99% purity.
It has been found that during shut down of the inventive process, higher molecular weight polymers of acetaldehyde tend to form in the base of the second distillation tower. To avoid or minimize the formation of these polymers, a constant flow of solvent is passed through the base of the column. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a Continuation-in-Part of U.S. Ser. No. 12/632,023 filed on Dec. 7, 2009 titled “DIGITAL RADIOGRAPHIC DETECTOR WITH BONDED PHOSPHOR LAYER” by Hansen et al., incorporated herein by reference.
FIELD OF THE INVENTION
The invention relates generally to the field of digital radiography and more particularly relates to an improved digital radiographic detector with a scintillator layer having a radiation sensing element coupled to a photosensor array.
BACKGROUND OF THE INVENTION
Systems for acquiring radiographic images are widely used in medical and dental care. Due to recent advances in component miniaturization, data transmission and processing speed, and with improved image processing and display capabilities, apparatus and methods for obtaining radiographic images directly in digital format are increasingly being used. With digital radiography, the radiation image exposures captured on radiation-sensitive phosphor layers are converted, pixel by pixel, to electronic image data which is then stored in memory circuitry for subsequent read-out and display on suitable electronic image display devices.
In typical digital radiography of the indirect type, a radiation sensing material, more generally termed a phosphor layer or scintillator, converts incident x-rays to visible light, which is then detected by a photosensor array that converts light intensity information to a corresponding electronic image signal. An intermediary fiber optic element may be used to channel the light from the phosphor layer to the photosensor array.
The perspective view of FIG. 1 shows a partial cutaway view of a small edge portion of a digital radiography (DR) detector 10 of the indirect type. A phosphor layer 12 , formed from radiation sensing materials, responds to incident x-ray radiation at a higher energy level by generating visible light at a lower energy level that is, in turn, detected by a detector array 20 . An optional fiber optic array can be provided for directing light from phosphor layer 12 toward detector array 20 . Detector array 20 has a two-dimensional array having many thousands of radiation sensitive pixels 24 that are arranged in a matrix of rows and columns and are connected to a readout element 25 . As shown at enlarged section E, each pixel 24 has one or more photosensors 22 and includes an associated switch element 26 of some type. To read out image information from the panel, each row of pixels 24 is selected sequentially and the corresponding pixel in each column is connected in its turn to a charge amplifier (not shown). The outputs of the charge amplifiers from each column are then applied to other circuitry that generates digitized image data that can then be stored and suitably processed as needed for subsequent storage and display.
In conventional DR detectors 10 , phosphor layer 12 is a scintillating material, excitable to spontaneously emit light upon receiving x-ray radiation. Detectors using a storage phosphor material are also envisioned. When a storage phosphor material is used as the radiation sensing element in phosphor layer 12 , the material is excitable to emit light energy in response to a stimulating energy, such as energy from an optical, thermal, or electrical energy source. Suitable photostimulable storage phosphors include BaFX:Eu 2+ types, such as BaFBr 2 :Eu 2+ , BaFCl:Eu 2+ , for example.
Indirect DR imaging, using components arranged as in FIG. 1 , shows promise for providing improved diagnostic imaging performance with high levels of image quality. However, some drawbacks remain. Because scintillating phosphor layer materials respond to incident x-ray radiation by emitting light over a broad range of angles, there is some inherent amount of scattering in the indirect detection process. Image sharpness is degraded when the visible light emitted from the phosphor is allowed to spread from its point of origin. The farther the emitted light spreads before detection by the photosensor, the greater the loss of light and sharpness. Any type of gap between the phosphor layer and its corresponding photodetector array can allow light to spread and cause consequent loss of image quality. For this reason, it can be particularly important to place the phosphor layer 12 ( FIG. 1 ) as close to the photodetector (detector array 20 ) as possible.
In addition to losses from spreading and scattering, some further loss of light can occur due to reflection, such as where the light traverses an interface to a material with lower refractive index. Reflected light returning toward the phosphor layer may be reflected again by the phosphor and can travel to the photosensor in a position that is even farther from its point of origin, thus further degrading the sharpness of the image. This type of effect reduces the overall optical efficiency of image formation due to loss of light, signal crosstalk, and related effects, and tends to degrade image quality.
Phosphor layers used to convert x-rays to visible light in radiography are typically prepared by one of two methods. One method is to mix particles of phosphor with a binder and form this mixture into a sheet, usually by coating the mixture onto a carrier film. Another method is to evaporate phosphor onto a sheet substrate, forming needle-like structures. In both methods, the phosphor layer is covered with a protective coating to prevent physical and chemical damage.
The cross-sectional side view of FIG. 2 shows the layered arrangement of conventional digital detector 10 and shows where adhesive is commonly used. Phosphor layer 12 typically is provided on a substrate 14 and is optionally affixed to a fiber optic array 52 , which is, in turn, affixed and optically coupled to detector array 20 . An adhesive layer 28 is provided between detector array 20 and fiber optic array 52 and between fiber optic array 52 and phosphor layer 12 . In conventional practice, substrate 14 may also support additional components as shown subsequently, including a carbon-pigmented black layer for absorbing leakage light and a pigmented white layer for reflecting some portion of the scattered light back through phosphor layer 12 .
Among methods employed for improving optical coupling between the scintillator screen and the detector are the following, represented schematically in FIGS. 3A through 3F :
(i) Applying continuous pressure between the phosphor layer and the detector array, thereby maintaining physical contact between these assemblies. This type of solution, shown by arrows in FIG. 3A , can be difficult to maintain across the full surface of the detector. Moreover, it is difficult to make a digital radiography sensor as thin as necessary if mechanical clamping or hold-down devices are employed in order to maintain optical contact between the phosphor layer and photosensor array. Uniformity of optical contact is a must. Where an air gap occurs, the light transmission and the spatial resolution (MTF) would be significantly degraded.
(ii) Depositing the phosphor material directly onto the photodiode array of detector array 20 . FIG. 3B shows a deposition apparatus 50 for forming scintillator layer 12 . This method assures physical contact, hence good optical contact. However, this type of processing can be complex, may risk damage to the photodiode array and can be very expensive. Detector array 20 is an expensive device, making it impractical to use as a “substrate” for deposition or coating of materials. Uniformity of deposition also presents an obstacle that makes this type of solution less than desirable.
(iii) Use of a fiber-optic array 52 , also termed a fiber optic plate or tile, between detector array 20 and phosphor layer 12 , as shown in FIG. 3C . Array 52 is an optical device consisting of several thousands of glass optical fibers 54 , each a few micrometers in diameter, bonded in parallel to one other. Each optical fiber acts as a light guide. Light from the radiation image is transmitted from phosphor layer 12 to the photodiode array of detector array 20 through each fiber 54 . A typical fiber optic array is about 3 mm thick. Phosphor layer 12 is disposed on one surface of fiber optic array 52 , then the other surface of fiber optic array 52 is pressed against detector array 20 . The fiber optic array provides high-resolution imaging and, with some types of Complementary Metal-Oxide Semiconductor (CMOS) and Charge-Coupled Device (CCD) photosensor devices, can be useful for providing a measure of protection of the photosensors from high radiation levels. However, this is at the cost of considerable light loss (about 37%). Fiber optic array transmittance is about 63% for Lambertian light at the wavelength of 0.55 um. In addition, air gaps 44 can still occur on either surface of fiber optic array 52 . This solution, therefore, also encounters the problems described in (i) and shown in FIG. 3A .
(iv) Depositing a phosphor layer directly onto the fiber-optic faceplate. FIG. 3D shows this hybrid solution. This solution reduces or eliminates air gaps 44 between phosphor layer 12 and fiber optic array 52 ; however, there can still be an air gap problem at the other surface of fiber optic array 52 . This solution also suffers from lowered transmittance as at (iii).
(v) As in FIG. 3E , depositing a phosphor layer directly onto the fiber-optic faceplate as in (iv) and applying an optical adhesive 56 between the coated fiber optic array 52 and detector array 20 . As with methods (iii) and (iv) just given, this method suffers from the inherently lower transmittance caused by the fiber-optic faceplate, fiber optic array 52 .
(vi) As in FIG. 3F , insertion of a conventional optically transparent polymer layer 58 between phosphor layer 12 and detector array 20 . The optical polymer materials used for this purpose may be in the form of fluid, gel, thermoplastic material, or glue. Each of these optical polymers has accompanying problems. Optical fluids are the most convenient to apply. However, as true fluids, they require containment or will otherwise tend to flow out from the optical interface if unsealed. Optical gels are non-migrating and do not require containment seals. However, they are too soft to provide dimensional rigidity, and may swell with prolonged exposure or at elevated temperatures. Optical thermoplastics (such as elastomers and resins) include soft plastics that, when cured, provide some dimensional rigidity. However, an additional thermal or radiation process for curing is generally required; such processing can be risky for electronic components of detector array 20 . Optical glues exhibit similar problems as optical gels. It is also difficult to apply a uniform thickness of glue between the phosphor layer and the detector array. One solution for this problem, proposed in U.S. Pat. No. 5,506,409 to Yoshida et al. entitled “Radiation Detecting Device and the Manufacture Thereof”, is the use of spherical spacers to ensure the proper adhesive thickness. However, this requires a number of added steps for proper adhesion, with some complexity and risk of irregular spacer distribution.
Another method of constructing a digital radiography detector is to affix the phosphor layer directly to the fiber optic element or photosensor. In this case, there is an intervening layer of adhesive between the phosphor layer and the fiber optic array or photosensor. The phosphor may thus be optically coupled to the fiber optic element or to the photosensor, therefore reducing the amount of light that is reflected and refracted at the screen surface. This method is proposed, for example, in commonly assigned U.S. patent application Ser. No. 12/104,780 entitled DIGITAL RADIOGRAPHY PANEL WITH PRESSURE-SENSITIVE ADHESIVE FOR OPTICAL COUPLING BETWEEN SCINTILLATOR SCREEN AND DETECTOR AND METHOD OF MANUFACTURE by Yip, published as U.S. Patent Application Number 2009/0261259. To reduce the likelihood of losses due to reflection, the Yip disclosure proposes using an intermediary pressure-sensitive adhesive material between the phosphor layer and the photosensors and matching the refractive index of the pressure-sensitive material with that of the phosphor layer and that of the photosensor array. This method may provide a measure of improvement for rigid flat panel detectors that have relatively large imaging areas and can be advantageous where no fiber optic array is used. However, this method is not suited to the requirements of an image detector for dental imaging, where a low profile detector is most advantaged and where high image sharpness is a requirement. Use of intermediary materials in the light path can also be a disadvantage for applications in which more flexible detector materials are more desirable. Moreover, even where the index of refraction is closely matched to materials at the interface, any intervening adhesive layer increases the phosphor layer-to-detector distance over which the light tends to spread. Thus, sharpness degradation can still occur with this solution.
Thus, it is seen that there is a need for a digital radiographic detector that is suited for intra-oral imaging and that provides optical coupling between the photosensor array and the phosphor layer.
SUMMARY OF THE INVENTION
It is an object of the present invention to advance the art of digital radiography. With this object in mind, the present invention provides a digital radiographic detector comprising: a radiation sensing element comprising a particulate material dispersed within a binder composition, wherein the binder composition comprises a pressure-sensitive adhesive, wherein the particulate material, upon receiving radiation of a first energy level, is excitable to emit radiation of a second energy level, either spontaneously or in response to a stimulating energy of a third energy level; and an array of photosensors wherein each photosensor in the array is energizable to provide an output signal indicative of the level of emitted radiation of the second energy level that is received; wherein the radiation sensing element bonds directly to, and in optical contact with, either the array of photosensors or an array of optical fibers that guide light to the array of photosensors.
It is a feature of the present invention that it employs a particulate radiation sensing material that is embedded or suspended within a layer of pressure sensitive adhesive, and is thus able to provide optical contact between the light-emitting element of the digital radiography detector and its fiber optic array or, where the fiber optic array is not used, its photosensor.
An advantage of the present invention is that it provides improved optical coupling between light emissive and light-sensing components and eliminates the need for a separately applied adhesive layer.
These objects are given only by way of illustrative example, and such objects may be exemplary of one or more embodiments of the invention. Other desirable objectives and advantages inherently achieved by the disclosed invention may occur or become apparent to those skilled in the art. The invention is defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of the embodiments of the invention, as illustrated in the accompanying drawings. The elements of the drawings are not necessarily to scale relative to each other.
FIG. 1 is a perspective, partial cutaway view showing a small portion of a digital radiography detector device.
FIG. 2 is a cross-sectional view of a conventional detector device, showing the arrangement of adhesively affixed layers.
FIGS. 3A , 3 B, 3 C, 3 D, 3 E, and 3 F are schematic cross-sectional views that illustrate various methods that have been attempted for improving optical coupling between the phosphor layer and the photosensor array in a digital radiography sensor.
FIG. 4 is a cross-sectional view of a digital detector device with bonded phosphor layer according to one embodiment.
FIG. 5 is a cross-sectional view of a digital detector device with its phosphor layer bonded to a fiber optic array according to an alternate embodiment.
FIG. 6 is a table comparing formulations of conventional detectors to a detector formed according to the present invention.
FIG. 7 is a perspective exploded view showing an intra-oral detector using the digital radiography detector of the present invention.
FIG. 8 is a perspective view showing an assembled intra-oral detector using the digital radiography detector of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The following is a detailed description of the preferred embodiments of the invention, reference being made to the drawings in which the same reference numerals identify the same elements of structure in each of the several figures.
In the context of the present invention, the term “optical contact” has its conventional meaning as understood by those skilled in the optical arts. Optical contact between two surfaces along a light path is considered to be “airtight” physical and optical contact between the two surfaces. In conventional, glueless optical contact, two surfaces are in intimate physical contact without an intervening cement or adhesive.
In the context of the present invention, the terms “radiation sensing material”, “scintillator”, “scintillator layer”, “scintillator element”, and “phosphor layer” are interchangeable, each referring to the component of a digital radiography detector that acts as a radiation sensing element that, upon irradiation at a given level of radiation, is excitable to emit a corresponding radiation of lower energy, the intensity of which is proportional to the intensity of the incident radiation. The emitted radiation may be emitted spontaneously or upon stimulation, such as upon stimulation with optical, thermal, or electrical energy.
In the context of the present disclosure, the term “digital radiography detector” is considered to encompass both digital radiography (DR) detectors of the indirect type and computed radiography (CR) detectors that include an array of photosensors bonded to the radiation sensing layer that, upon receipt of an external excitation or stimulation energy, emits light energy corresponding to the amount of received x-ray radiation energy.
The apparatus and method of the present invention provide an improved digital radiography detector by eliminating the intervening adhesive layer that bonds the phosphor layer either to a fiber optic array or directly to the detector array. Using the method of the present invention, the phosphor layer bonds to its adjacent surface directly to provide optical contact and reduce scattering or spreading of light and thus reduce consequent cross-talk between pixels.
For use in dental imaging and related applications, relatively high resolution imaging is needed. To achieve this, relatively thin layers of phosphor material are used and good optical coupling with each detector is necessary. A fiber optic array element is generally used, since this device is beneficial for reducing the likelihood of radiation damage to photosensor circuitry.
In order to serve as a scintillator or radiation sensing element, embodiments of the present invention use a phosphor layer including a particulate material that is formulated to adhere directly to the photosensor array or, optionally, to the fiber optic array, without the need for an intervening adhesive layer, as was described earlier with reference to FIG. 2 . Referring to FIG. 4 , a digital radiography detector 100 has a phosphor layer or scintillator element, radiation sensing element 30 , that bonds directly to detector array 20 and is in optical contact with the photosensors in detector array 20 .
FIG. 4 also shows exemplary support layers that can be considered as part of substrate 14 in various embodiments of the present invention. A base plate 32 provides a supporting surface for a carbon-pigmented black layer 34 for absorbing light leakage and reducing scattering effects. Black layer 34 is overlaid onto a pigmented white layer 36 . White layer 36 reflects some portion of the scattered light back through, radiation sensing element 30 . In the alternate embodiment of FIG. 5 , radiation sensing element 30 bonds directly to fiber optic array 52 and is in optical contact with the surface of the fiber optic array 52 .
Radiation sensing element 30 comprises a particulate phosphor or other suitable inorganic radiation sensing material dispersed in an adhesive. The phosphor itself is gadolinium oxide phosphor GOS:Tb in one embodiment. In general, the phosphor that is used can be any particulate substance that converts x-rays of the energy appropriate to the imaging task to visible light of an energy appropriate for sensing by the photosensors of detector array 20 and, optionally, for transmission to detector array 20 by the fiber optic elements. The transformation of higher energy x-ray light to lower energy (visible or other) light can be spontaneous or in response to stimulating energy from an external source, which may apply a third energy level of optical, thermal, electrical, or other type. Radiation sensing element 30 can have a supporting substrate 14 that serves as an optional carrier or backing layer, as shown in FIGS. 4 and 5 .
Radiation sensing element 30 may be formed by preparing a dispersion of phosphor particles, adhesive and solvent, applying this dispersion in a layer of uniform thickness to the carrier layer of substrate 14 by any appropriate coating method, and drying the applied dispersion. A temporary protective film may be applied to the surface of the phosphor layer after it is formed onto substrate 14 , in order to keep it free from contamination. This temporary film is then removed before adhering radiation sensing element 30 to the photosensor array.
Comparative Examples
The table in FIG. 6 shows formulation and results for a number of different DR detector embodiments, comparing conventional phosphor: binder compositions (examples A, B, C, and D) with the formulation used in an embodiment of the present invention (example E).
Phosphor layers for the examples were prepared as follows. Examples A through D were prepared by dispersing GOS:Tb phosphor particles in a typical polyurethane binder at conventional binder: particulate proportions, typically about 27:1. This mixture was coated by knife blade onto a carrier film at a coating weight of 3.2 g/dm2. Additionally, a protective layer of 13 um thickness (nominal) was coated over the phosphor layer for Examples B and D. For Examples A and B, pressure was applied to maintain contact between the phosphor layer and photodetector array; however, optical contact was not achieved. For Examples C and D, an adhesive was applied between the phosphor sheet and the fiber optic array for directing light to the photodetector array. Relatively good optical coupling was achieved by this method, but not optical contact, as has been defined earlier.
Example E was prepared according to the present invention, using a pressure-sensitive adhesive directly as the binder, in a binder: particulate proportion of 9:1 (nominal). The phosphor layer of Example E was bonded to a fiber optic element directly with no adhesive coating prior to bonding. No protective layer was used.
The right-most two columns of the table in FIG. 6 show performance results for each formulation method that was used in these Examples. Limiting resolution, shown in line pairs (lp) per mm indicate that the inventive embodiment of Example E markedly out-performs the more conventional formulations. The inventive embodiment of Example E also shows improved performance with respect to relative detector response, normalized to the performance of the conventional detector of Example A.
FIGS. 7 and 8 are perspective views of an intra-oral detector 60 , in exploded and assembled forms, respectively, using digital radiography detector 100 of the present invention. Digital radiography detector 100 is supported between a lower cover 62 and upper cover 66 that provides connections for obtaining image data from a cable 64 . Alternately, a wireless interface (not shown) could be provided. In the wired version shown, cable 64 has a connector 68 and seal 70 for protecting the cabling connections.
Materials and Fabrication
Referring again to FIG. 4 , substrate 14 and radiation sensing element 30 of digital radiography detector 100 can comprise multiple components. The base support material of base plate 32 may be any suitable material that will pass x-rays without diffraction and can be easily cleaned. Typical materials used for this purpose include PET (polyethylene terephthalate) or similar polyester support. A suitable material is a clear polyester of the thickness of about 10 mils or 1/100 of an inch (0.254 millimeters).
Carbon-pigmented black layer 34 is formed of any suitable material that will provide a uniform light-absorbing layer that blocks the passage of light. Generally, the layer is comprised of carbon black and a small amount of polymer for casting and layer forming. In one embodiment, this polymer is cellulose acetate; other suitable polymers can be used. White layer 36 is formed of any suitable material that reflects and enhances the light from the phosphor. Preferably, white layer 36 includes a titanium dioxide, TiO 2 pigment, east with a polymer such as cellulose acetate. Also suitable would be a film containing titanium dioxide, possibly with micropores, such as commercially available titanium dioxide-containing polypropylene film that has been stretched to form micropores around the titanium dioxide particles.
The phosphor layer used for the scintillator in embodiments of the present invention includes phosphor particles formed into a layer with a binder of adhesive material selected from the known phosphor materials that emit light in response to incident x-rays. Suitable phosphor materials include Lutetium oxysulfide and Gadolinium oxysulfide (Gd 2 O 2 S), for example. Preferred materials include terbium and gadolinium oxide phosphors, including Gd 2 S 2 O:Tb which is advantaged due to its ready availability and cost.
The term “binder”, as utilized herein, means the material in phosphor layer of radiation sensing element 30 that is not phosphor itself. The proper amount of binder is needed. Too much of this adhesive material causes blocking of the coated layers when wound or stacked, while too little reduces the pressure sensitive adhesive sealing properties which can result in the phosphor layer peeling away from the surface to which it is affixed. The binder encapsulates the phosphor particles and provides a suitable bond to detector array 20 ( FIG. 4 ) or, optionally, to fiber optic array 52 ( FIG. 5 ). The binder must meet these requirements:
(i) Pressure-sensitive, capable of sealing with applied heat and pressure, but not tacky to the touch at room temperature and not blocking when wound or stacked;
(ii) Optically clear and colorless;
(iii) Not sensitizing to the phosphor particles.
(iv) At least moderately viscous for coating application; and
(v) Low glass transition temperature, near about −38° F.
The binder for the phosphor layer may be a polyester or polyether. The binder composition preferably contains solids of about 38 to 46 parts of acrylic adhesive latex, based upon 100 total parts, in solvents well-known for use with adhesives and latexes.
A preferred binder for the invention includes a non-crosslinked acrylic polymer adhesive that, upon evaporation of its solvent, forms a matrix material around and between the phosphor particles. One exemplary acrylic adhesive with suitable properties is Morstik, available from Rohm&Haas/Dow Chemical, Inc. This layer of phosphor particles and the non-crossed linked adhesive is then activated to form a permanent bond under moderate heat and sealing pressure.
Radiation sensing element 30 is cast from a mixture of binder provided with a solvent material to enable casting. Solvents for casting the phosphor layer may include ethyl acetate, methyl acetate, acetone, and isopropyl alcohol. The solvent is evaporated to form the layer. Generally, to provide a nominal 9:1 particulate to binder ratio, radiation sensing element 30 contains between 85 and 95% by weight of phosphor. Binder, including any filler, is between 5 and 15% by weight, after drying. A preferred amount is between about 8 and 12% by weight of the binder, as this gives good binding properties to the layer as well as a high amount of phosphor for improved imaging.
The formulation and assembly of a fiber optic faceplate for fiber optic array 52 is known to those skilled in the optical component fabrication arts. Preferably the fiber optic faceplate has a thickness of about an eighth of an inch (approximately 2 millimeters). Fiber diameter is generally about 6 um.
The composition of the photosensor array that is in contact with the fiber optic element is known. The types of optical sensors that are energizable to provide an output signal in response to received light are composed of a plurality of sensor sites or photosites, arranged in a matrix. The sensors themselves can be Charged-Coupled Devices (CCD) or Complimentary Metal-Oxide Semiconductor (CMOS) detectors, or some other type of photosensing device, for example. Some type of protective covering for this underlying circuitry is typically provided.
In one embodiment, digital radiography detector 100 is fabricated by bonding radiation sensing element 30 directly to fiber optic array 52 or to detector array 20 , using heat and pressure for glueless optical contact. To minimize air pockets or voids, this process is preferably carried out under vacuum.
The invention has been described in detail with particular reference to a presently preferred embodiment, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention, The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the appended claims, and all changes that come within the meaning and range of equivalents thereof are intended to be embraced therein.
PARTS LIST
10 . DR detector
12 . Phosphor layer
14 . Substrate
20 . Detector array
22 . Photosensor
24 . Pixel
25 . Readout elements
26 . Switch element
28 . Adhesive layer
30 . Radiation sensing element
32 . Base plate
34 . Black layer
36 . White layer
44 . Air gap
50 . Deposition apparatus
52 . Fiber-optic array
54 . Optical fiber
56 . Optical adhesive
58 . Polymer layer
60 . Intra-oral detector
62 . Lower cover
64 . Cable
66 . Upper cover
68 . Connector
70 . Seal
100 . Digital radiography detector
E. Enlarged section | A digital radiographic detector having a radiation sensing element with a particulate material dispersed within a binder composition, wherein the binder composition includes a pressure-sensitive adhesive, wherein the particulate material, upon receiving radiation of a first energy level, is excitable to emit radiation of a second energy level, either spontaneously or in response to a stimulating energy of a third energy level. There is an array of photosensors, each photosensor in the array energizable to provide an output signal indicative of the level of emitted radiation of the second energy level that is received. The radiation sensing element bonds directly to, and in optical contact with, either the array of photosensors or an array of optical fibers that guide light to the array of photosensors. | 6 |
[0001] The present application is related to provisional patent application entitled “Rectangular-Hole Snap-In Fastener”, Ser. No. 60/183,974, filed Feb. 22, 2000, priority from which is hereby claimed.
FIELD OF THE INVENTION
[0002] This invention relates to snap engagement fastening for quickly installed fasteners to secure two panels or sheets. In particular, it relates to panel fasteners which permit the manual securement and release of two panels or sheets.
BACKGROUND OF THE INVENTION AND PRIOR ART
[0003] The process of assembling equipment into racks involves attaching the equipment shelf to the side rails of a rack that has a series of vertically spaced rectangular holes in the side rails. Prior art fasteners for this type of rack system utilize a cage nut assembly, washer, and screw combination. This process requires that a cage nut be installed in the rack in the correct vertical position which requires a good deal of manual dexterity, and a special tool. Next, the shelf is placed so that the holes are aligned with the cage nut, and then manually held in place while a screw and washer are put into place and tightened. This operation needs to be repeated on both sides of the rack and two to four fastener assemblies may be required for each shelf Removal of the shelf requires that all screws be removed and such loose screws and washers are then prone to be lost or fall into the sensitive electronic equipment. If retained threaded fasteners are used, each of them will require multiple turns by hand or with a tool for installation and removal. Thus, the present method of assembling rack systems is both time consuming and cumbersome. There is therefore a need to simplify the process of assembling equipment shelves to a rack having vertically spaced square holes.
SUMMARY OF THE INVENTION
[0004] The present invention significantly simplifies affixing an equipment shelf to the sides of the equipment rack. A novel snap-in fastener for rectangular holes has been developed which is permanently affixed to the shelf Attachment of the shelf is accomplished by merely snapping the fastener into the rectangular holes in the side rails of the rack. Removal is accomplished by simply pulling on the shelf or the fastener itself. There is no loose hardware that can be lost or cause damage to the equipment. While the present invention is an advancement in the art of assembling rack systems, the fastener disclosed herein is not limited to this specific application. It may be used in any application where panels need to be quickly secured without tools. This invention provides a fastener with several important features. First, the fastener has a clinch feature that provides permanent attachment to a first sheet of metal. Secondly, integral snap-arms provide a reusable means to attach the first sheet to an appropriately-sized rectangular hole in a second sheet. In addition, other optional features such as a locking mechanism and finger grips may be included.
[0005] The clinch attachment works by displacing metal from the first sheet into the undercut of the fastener. Once the metal has entered the undercut the part is permanently attached to the first sheet. The clinch profile and the overall envelope of the fastener can be sized for a wide variation of panel sizes and thickness.
[0006] The snap-arms include tapered barbs that allow the ends of the arms to initially engage the rectangular hole on the second sheet. With continued axial application of force, the arms flex inward and pass through the hole, at which point the arms return to their original position and thus retain the fastener in the hole. Pulling on the fastener or the shelf releases it in a similar manner.
[0007] A further embodiment of the fastener includes a locking mechanism. Once the second sheet has been engaged, a lock clip is pushed forward and snaps into place between the snap-arms thus preventing the fastener from loosening or being removed. This is accomplished by the lock clip acting as a positive stop to prevent the snap-arms from flexing inward and disengaging the hole in the second sheet. The fastener is then unlocked by simply pulling the lock clip into the unlocked position. In the unlocked position, the locking mechanism is out of the path of the flexing arm and allowing separation of the two sheets. The lock clip may include detents to ensure that the lock is held out of the path of the snap-arms while it is unlocked. The lock clip also prevents premature disengagement due to vibration. The lock clip may be molded from plastic, thereby providing a means of color identification and matching.
[0008] Another embodiment includes finger grips integral with the fastener. This allows parts of the fastener to function as a handle for the equipment. The extension of the fastener body is ergonomically designed and eliminates the need for additional hardware such as handles and/or knobs. Also by locating the finger grips directly behind the snap feature, the applied forces are directed axially, reducing lateral stresses on the fastener, thereby reducing the required force of assembly and disassembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIGS. 1 and 1A are top right front isometric assembly views of the present invention;
[0010] [0010]FIG. 2 is top right front perspective view of the present invention securing parallel sheets;
[0011] [0011]FIG. 3 is a top right rear isometric view of the present invention;
[0012] [0012]FIGS. 4 and 5 are top views partially sectioned showing the lock clip in different positions;
[0013] [0013]FIG. 6 is a front sectional view taken from FIG. 4 as shown in that Figure;
[0014] [0014]FIG. 7 is a top view of the main body element of the present invention;
[0015] [0015]FIG. 8 is a side view of the lock clip element of the present invention;
[0016] [0016]FIG. 8A is a sectional view taken from FIG. 8.
[0017] FIGS. 9 - 12 show various alternate sheet aperture configurations;
[0018] [0018]FIG. 13 is a top view of an alternate embodiment of the main body portion;
[0019] FIGS. 14 - 16 are top views of alternate extension arm attachment means;
[0020] [0020]FIG. 17 is a rear view of the lock clip element shown in isolation;
[0021] [0021]FIG. 18 is a side view of the lock clip shown in FIG. 17;
[0022] [0022]FIG. 19 is a rear view of an alternate embodiment of the lock clip of the present invention shown in isolation;
[0023] [0023]FIG. 20 is a side view of the lock clip shown in FIG. 19;
[0024] [0024]FIG. 21 is a top right rear isometric view of an alternate embodiment lock clip shown in isolation; and
[0025] [0025]FIG. 22 is a side view of the alternate lock clip shown in FIG. 21.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] [0026]FIGS. 1, 1A, 2 , and 3 depict the basic features of the fastener of the present invention in perspective view. FIG. 1 shows the fastener 1 with its longitudinally extending side extensions 1 a and snap-arms 1 b aligned with properly sized mounting hole 4 in first sheet 2 prior to installation. In FIG. 1A, the fastener is permanently clinched to first sheet 2 and in position, aligned with hole 5 , for attachment to second sheet 3 . FIG. 2 shows the three elements in FIGS. 1 and 1A joined. The second sheet 3 is releasably attached by the fastener to the first sheet by means of resilient snap-arms 10 of the fastener which lie between the side extensions on either side of the longitudinal axis of the fastener. The snap-arms have barbed ends which grip the side edges of hole 5 in the second sheet 3 . Lock clip 6 is shown in its locked position with legs which extend between the snap-arms to positively wedge them apart. FIG. 3 is a perspective view from the attachment end of the fastener and more clearly shows the basic elements of a fastener including side extension 1 a , lock clip 6 , snap-arms 10 and the clinch feature 1 b . Lock clip 6 is shown in the locked position.
[0027] [0027]FIGS. 4 and 5 are cross-sectional views of the assembled sheets shown in FIG. 2, with FIG. 4 showing the fastener with lock clip 6 in its locked position and FIG. 5 showing the fastener with the lock clip in the unlocked position. Referring first to FIG. 4, the sides of the main body of the fastener are shown in detail clinched into first sheet 2 . Displacer 7 forces the material of sheet 2 into undercut 8 as it is pressed into the sheet. Snap-arms 10 extend through the backside of second sheet 3 which is attached by direct contact with barbs at the ends of the snap-arms. In this Figure, the lock clip is in its locked position whereby the clip legs are moved between the ends of the snap-arms to hold them wedged apart. It will be understood that the dimensions of the fastener and the relationship between the barbs and the clinch features on the main body of the fastener to the thickness of the attached panels are critical to the snap attachment.
[0028] Referring now to FIG. 5, the same elements in FIG. 4 are shown except that lock clip 6 is in its retracted and unlocked position. In this position, the legs of the lock clip are withdrawn from the ends of the snap-arms and therefore the barbs are not blocked from flexing inward as the fastener is pulled out of second sheet 3 . The snap-arms and configuration of the snap attachment barbs are designed to provide the desired amount of insertion and pull-out force.
[0029] Referring now to FIG. 6, a cross-section taken from FIG. 4 as shown in that Figure, depicts greater detail of the snap-arms 10 and the lock clip 6 . From this view, lock clip 6 can clearly be seen boxing-in snap-arms 10 which abut shoulders 6 a on the inside surface of the lock clip arms and are constrained by the side surfaces of inward facing tabs 19 . Without inward deflection, the barbs at the ends of the snap-arms will not release the second sheet and thus engagement of the clip lock provides positive attachment of the second sheet to the fastener.
[0030] When in their locked position, the side edges of the snap-arms correspond in dimension to the dimension of the apertures in the sheets so that the sheets are retained laterally, axially, and against rotation. Hence, the sheets are positively secured, being held against movement in all directions. The side extensions 1 a of the main body of the fastener I are spaced from the lock arms by a gap 10 a to permit the snap-arms 10 to flex.
[0031] Referring now to FIG. 7, the main body of the fastener is shown. Snap-arms 10 are separated by a gap K and are sized to ensure that the deflection required for snapping is within the elastic region of the material. Surface 13 is the resting surface for the second sheet that provides a positive stop for the snap-in motion when the clinched sheet 2 is thinner than the height J of the clinch feature. When the clinched sheet 2 is thicker than the height of the clinch feature, the clinched sheet acts as the positive stop for the snap-in motion, both sheets being held in face-to-face contact. A lead-in taper 16 on the barbs 18 of the arms 10 forces the arms to flex inward as they are pushed against the sides of hole 5 in the second sheet. Once fully within hole 5 of the second sheet, the arms 10 containing the barbs 18 return to their normal unflexed position on the back of the second sheet 3 to retain the first sheet and fastener assembly axially in sheet 2 . The back taper 17 of the barbs allow the fastener to be removed from the hole in a manner similar to the function of taper 16 . Angles 16 and 17 control the amount of force that is required to install and remove the fastener. Typically angle 16 is 60 degrees and angle 17 is 45 degrees so that the installation force is lower than the removal force. In this Figure, the clinch displacer 7 and undercut 8 are again clearly seen. Guide II provides a clearance fit to the first sheet mounting hole and acts as a lead to aid in aligning the fastener with sheet 2 during installation. Surface 12 is a positive stop for the installation clinch process into the first sheet. Finger grip 14 is large enough to be gripped easily and the outwardly curved radius 15 is ergonomically designed.
[0032] The view direction of FIG. 8 is rotated 90 degrees relative to FIG. 7 and shows the side view of the lock clip 6 with legs 28 having inward facing tabs 19 at their ends. As shown in FIG. 6, these tabs fit between the snap-arms 10 of the fastener and are oriented 90 degrees to the snap-arms to hold them positively wedged apart, resisting inward deflection. With the lock clip tabs 19 in the locked position against the snap-arms, the snap-arms box in the inside surfaces of the rectangular hole of the second sheet to secure the two sheets against relative motion The lock clip tabs 19 have a leading taper 20 that allows the lock to snap into place over the body of the fastener when the two pieces are initially assembled. Radii 21 along the bottom corners of each tab 19 are compatible with the relief radii 22 (FIG. 7) on the snap-arms to provide a close fit in the unlocked position. Lock recess 9 of FIG. 7 is sized to closely receive the base of the lock clip so that its outer surface is flush with the finger grips of the fastener when in the locked position as shown in FIGS. 1, 2, and 3 . The lock recess 9 has parallel interior side larger than the space between the snap-arms 10 to give the lock additional stability in both the locked and unlocked positions. Surface 23 seats against the recess 9 of the fastener main body shown in FIG. 7 to provide a positive stop for the lock clip in the locked position. Detent 24 positions and holds the lock clip in the locked and unlocked positions. The outside surface of the snap-arms includes ergonomic series of raised ridges 27 so that the lock can be easily pushed and pulled. The engagement and disengagement requires only enough force to move the detents 24 and 26 past the body 25 shown in FIG. 7.
[0033] [0033]FIG. 8A is a side view of FIG. 8. In FIG. 8A, the portion of the lock clip, L that remains outside of sheet 2 is wider than the dimension, K of the snap-arms shown in FIG. 7, to prevent rotation of the lock clip about 25 . Inward facing tab 19 extends from the end of leg 28 which also includes detent 24 that functions as explained above. The structure of tab 19 can be seen with greater clarity with reference to the embodiment shown in FIG. 21 which depicts the same tab structure but includes catch means.
[0034] FIGS. 9 - 12 show various sheet aperture configurations, FIGS. 9, 10 and 11 show alternate configurations of the apertures in the first sheet 2 . FIG. 12 shows the basic configuration of the rectangular hole of the second releasably attached sheet 3 . FIG. 9 shows the first of the two most simple variations of holes with which the clinch will work. Length “B” of the hole 4 must be carefully dimensioned to work with the clinch feature. The width “C” must be sized closely with the thickness of the fastener to reduce the possibility of misalignment during installation. In the preferred variation with the lock feature, an extension is required in the hole 4 to accommodate the lock. This is shown by dimensions “D” and “E”.
[0035] [0035]FIG. 10 is an alternate mounting hole suitable for clinch attachment and lock clearance. The diameter “F” corresponds with a circle circumscribed about the rectangle defined by dimensions “D” and “E”.
[0036] [0036]FIG. 11 shows a first sheet aperture which provides the greatest amount of sheet material around the opening for added sheet strength. This configuration has three rectangular holes. The central hole provides the relief for the lock arms and room for the snap-arms to flex. The two side holes are sized to provide a proper clinch attachment. Dimension “G” should be sized to accommodate side extensions 1 b that contains the clinch features 1 b . FIG. 12, shows the rectangle hole 5 of the second sheet 3 that receives the barbs of the snap-arms. The dimension “A” must be sized with respect to the width of the snap-arms and the barbs. Dimension A 1 of the rectangular hole 5 , must simply be greater than the thickness of the snap-arms. Dimension A 1 may be greater than the minimum to allow for lateral misalignment when multiple fasteners are used in the same sheet.
[0037] [0037]FIG. 13 shows an alternate embodiment of the fastener having a curved wall 29 for greater strength. This curve allows the fastener to withstand additional force during the installation of the clinch.
[0038] [0038]FIG. 14 shows greater detail of the clinch feature at the tip of the side extensions 1 b of the fastener. The individual numbered elements correspond to those described with regard to FIG. 7.
[0039] [0039]FIG. 15 shows an option to the clinch feature that allows the end of the side extensions of the fastener 31 to be folded over, thus permanently attaching it to a sheet. This configuration is optimal for attaching to very a hard sheet and any sheet sized correctly with the appropriate hole.
[0040] [0040]FIG. 16 depicts an optional method of attachment to the first sheet 2 that allows the ends of the fastener side extensions 34 to be snapped into the mounting hole. This method also allows affixation for any sheet hardness, given the correct thickness of the sheet and the correct hole configuration. With this method the fastener may be removed from the first sheet 2 in case of damage. The back angle 36 can be varied to increase or decrease the force required for removal.
[0041] FIGS. 17 - 21 show alternate embodiments of the lock clip. FIGS. 17 and 18 show an optional catch 37 on the lock. The catch ensures that the arms of the lock do not separate and add stability and strength to the lock clip. The catch includes leading taper 20 that allows the lock to be easily assembled to the fastener body. FIGS. 19 and 20 show an optional catch 39 and slot 40 combination that functions similarly to the corresponding features shown in FIGS. 17 and 18. The preferred material for the lock clip is a molded thermoplastic such as acetyl.
[0042] [0042]FIG. 21 shows a configuration of the lock clip that utilizes a “living hinge” molded from plastic. During assembly with the fastener body, the lock clip is folded along the hinges 41 . The jaws 39 snap over the barb 40 . Taper 42 on the outside of the lock is independent of the hinge configuration, and is preferred for all configurations of the lock clip. This taper guides the lock clip along the sides of the rectangular hole 5 in second sheet 3 as it slides forward from the unlocked to the locked position. The hole 43 aids in molding the lock clip as it helps to reduce the sink, or plastic shrinkage, in the thick section of the base.
[0043] [0043]FIG. 22 shows the lock clip configuration shown in FIG. 21 with the living hinge closed. Also shown in this figure are flaired projections 44 which provide a gripping surface that is oriented so that gripping force does not tighten the lock clip on the fastener base during the unlocking process.
[0044] It should be understood that there may be other modifications and changes to the present invention that will be obvious to those of skill in the art. From the foregoing description, however, the present invention should be limited only by the following claims and their legal equivalents.
What is claimed is: | A snap-in fastener secures two sheets together by snap fit. Extensions of the fastener body include a clinch feature that provides a permanent attachment to a first sheet of metal. Integral snap arms which extend beyond the opposite side of the first sheet provide a reusable means to attach to an appropriately sized hole in a second sheet thus uniting the two sheets. The sheets include rectangularly-shaped holes positioned in alignment through which the snap arms of the fastener pass to achieve attachment. A locking mechanism may be employed to hold the snap arms in their engaged position to prevent pull-out of the second panel. In addition, finger grips integral with the body of the fastener provide an ergonomically suitable handle for carrying the attached sheet. | 5 |
TECHNICAL FIELD OF THE INVENTION
The present invention relates to the construction of spacer frames for insulated glass panels and, more particularly, to a flexible corner connector for connecting adjacent spacer sections to form a spacer frame.
BACKGROUND OF THE INVENTION
Window panes or glass panels having two or more panes of glass separated by insulating air spaces are well known in the art. Typically adjacent glass panes are separated by a peripheral frame constructed from tubular spacer sections joined together at adjacent ends. To form a corner of the frame, adjacent spacer sections are connected by a connector to seal the spacer sections from condensable ambient moisture, and to position the spacer sections in the desired relative angular configuration. Typically, the connectors have first and second arms that are insertable into adjacent tubular spacer sections. The first and second arms of conventional rigid connectors, for use in rectangular windows, are configured to form a right angle.
Flexible connectors have also been developed that include first and second arm portions joined by a flexible hinge portion. This type of conventional connector enables adjacent frame sections to be connected linearly. The connected sections are then pivoted relative to each other into the desired angular configuration, flexing the connector at the hinge. In order to secure the sections in this configuration, conventional flexible connectors typically include mating portions on each arm of the connector that are engaged when the connector is flexed to the desired angular configuration.
One such conventional flexible connector is provided by U.S. Pat. No. 4,822,205 to Berdan. The connector includes opposing interlocking fins formed on each arm portion. The flexed connector is maintained in position by frictional engagement of the fins. This type of flexible connector has proved to be unsatisfactory for use with large frames because the stresses imparted on the connector by the frame sections overcome the frictional resistance to separation of the connector from the flexed configuration.
Other flexible connectors have been developed that overcome the problem of inadvertent connector separation by including opposing locking portions on the first and second arms of the connectors. The locking portions are snapped together when the connector is flexed. While this type of conventional connector does remain securely in a flexed configuration, the connector cannot be separated to the straightened configuration without the use of excessive force or destruction of the engaging locking portions. Straightening of a flexed connector may be required during manufacture, or to repair leaking spacer frames in windows in which condensed moisture has formed.
SUMMARY OF THE INVENTION
The present invention is directed to a releasably securable flexible corner connector for connecting adjacent first and second spacer sections in a spacer frame for an insulated glass panel. The corner connector includes first and second arms that are connectable to the first and second spacer sections, respectively, and a flexible joint joining the first and second arms. The connector is further constructed and contoured such that the first arm can be selectively secured relative to the second arm in a desired angular orientation. To this end, the first arm includes a securement projection protruding adjacent the flexible joint, and the second arm includes a deformable portion adjacent the flexible joint. The securement projection of the first arm is engageable with the deformable portion of the second arm to deform the deformable portion. The deformed deformable portion exerts a compressive force on the securement projection to secure the first and second arms.
In a further aspect of the present invention, the second arm includes a recess formed adjacent the flexible joint. The deformable portion of the second arm comprises a deformable projection projecting from adjacent an edge of the open face of the recess, inwardly toward the bottom of the recess. When the connector is flexed, the securement projection of the first arm is insertable into the recess of the second arm, alongside the deformable projection to deform the deformable projection and secure the connector. In addition to the compressive force exerted by the deformed deformable projection, friction between the deformable projection and the securement projection serves to securely hold the corner connector in a flexed configuration.
In a still further aspect of the present invention, the securement projection of the first arm and the deformable projection of the second arm define opposing obtusely angled corners that engage when the connector is flexed. The deformable projection exerts a compressive force on both the first and second surfaces of the corresponding corner of the securement projection to further secure the connector in the flexed position.
Connectors constructed in accordance with the present invention are easily secured without the exertion of undue force. If necessary, during manufacture or for the purposes of repair, the connector can be unflexed by exerting a firm force on the connector, without causing damage to the connector, so that the connector can be reinserted when desired.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing features and advantages of the present invention will be readily understood by one of ordinary skill in the art, upon reading the following specification taken in conjunction with the appended drawings, wherein:
FIG. 1 is a pictorial view of a flexible corner connector constructed in accordance with the present invention;
FIG. 2 is a side elevation view of the unsecured corner connector shown in FIG. 1 connected to spacer frame sections;
FIG. 3 is a side elevation view of the corner connector of FIG. 2 in the secured (flexed) configuration; and
FIG. 4 is a partial side elevation of the secured corner connector of FIG. 3, showing detail of the deformed deformable projection.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of a corner connector 10 constructed in accordance with the present invention is shown in FIG. 1 in its unflexed, unsecured configuration. The corner connector includes a first elongate arm 12 and a second elongate arm 14 joined endwise by a flexible joint 15. The first and second arms 12 and 14 are similarly constructed with the exception of securement features to be discussed below. The arms 12 and 14 each have substantially rectangular cross sections. A first surface of each of the arms is formed with a series of transverse serrations 16. A series of tabs 18 protrudes generally orthogonally opposite the serrations 16 from a second surface of each of the first and second arms.
The function of the serrations 16 and tabs 18 is best understood in conjunction with FIG. 2, which shows the corner connector 10 engaging first and second spacer bar sections 20 and 22, respectively. The spacer sections 20 and 22 are of tubular construction, and typically are constructed from aluminum or steel. Each arm 12 and 14 includes a tapered leading end 24 and 26, respectively, to enable easy insertion of the arms into the respective spacer sections. Upon insertion of the arms into the spacer sections, the tabs 18 are flexed toward the flexible hinge 15 due to interference between the tabs and the sidewalls of the spacer sections 20 and 22. The flexed tabs exert a spring force against the sidewalls of the spacer sections to firmly connect the connector 10 to the spacer frame sections 20 and 22. The serrated edges 16 further aid in securing the corner connector to the spacer frame sections 20 and 22. Shoulders 28 and 30, respectively, are formed around each of the arms 12 and 14, in proximity to the flexible joint 15, to provide a stop for the ends of the tubular spacer sections 20 and 22. The arms 12 and 14 are dimensioned to block the ends of the frame sections 20 and 22, which may be filled with a desiccant 32, such as silica gel, as shown in FIG. 2.
The flexible joint 15 may be flexed to pivot the first and second arms 12 and 14 relative to each other to a desired angular configuration. The illustrated embodiment of the connector 10 is configured to allow flexing of the corner connector 10 to a right angle, as required for conventional rectangular windows. The first and second arms 12 and 14 include opposing complementary angled surfaces 34 and 36, respectively, formed adjacent the hinge 15, which contact each other when the corner connector is flexed to prevent further flexing past the right-angled configuration. However, it should be readily apparent that a corner connector could be constructed in accordance with the present invention to allow flexing of the connector to a different desired angular configuration, such as required for octagonal windows.
The corner connector 10 includes a mechanism to releasably secure the corner connector in the flexed configuration, as best understood with reference to FIGS. 1 and 2. The first arm 12 includes a securement flange 38 projecting from the stop surface 34 adjacent the serrated surface of the first arm 12. The flange 38 is angularly disposed to project outwardly away from the flexible joint 15, and toward the second arm 14. The flange 38 includes a ridge 40, having a generally semicircular cross section, formed along an edge of the flange's undersurface, adjacent the flange's distal end. The ridge 40 and undersurface of the flange 38 define an obtusely angled inner corner 42 that is transversely oriented with respect to the longitudinal axis of the first arm 12.
The second arm 14 includes a recessed slot 44 formed transversely between the stop surface 36 and the serrations 16. The second arm 14 further includes a transverse deformable flange 46 that projects inwardly from the stop surface 36, from one edge of the open face of the slot 44, toward the bottom of the slot 44. The flange 46 thus generally bifurcates the space within the slot 44. When viewed from the side, as in FIG. 2, the slot 44 thus defines a generally hook-shaped path. The distal end of the flange 46 defines a transverse obtuse outer corner 48 substantially corresponding to the inner corner 42 of the securement flange 38 of the first arm 12.
Reference is now had to FIG. 3 to describe the flexing of the corner connector to selectively engage the securement flange 38 with the deformable flange 46. As the first arm 12 is flexed toward the second arm 14, the securement flange 38 is inserted within the slot 44 alongside the deformable flange 46. As the flange 38 enters the slot 44, the distal end of the securement flange 38, including the ridge 40, causes the deformable flange 46 to be deflected toward the sidewall of the slot 44 closest in proximity to the hinge 15. When the connector is fully flexed to the secured position, the ridge 40 on the distal end of the securement flange 38 is inserted to just past the distal end of the deformable flange 46. The outside corner 48 on the flange 46 engages with the inside corner 42 on the flange 38.
Referring to the detailed view of FIG. 4, in this flexed, secured position, the deformable flange 46 is deflected from its relaxed position (shown in dashed lines). The deformable flange 46 is constructed of a stiff, resilient material, such as a polyamide plastic, commonly referred to as Nylon™. Due to the resilient deformation of the flange 46, the securement flange 38 is compressed between the flange 46 and the sidewall of the slot 44. Further, because of the engagement of the outer corner 48 of the flange 46 and inner corner 42 of flange 38, respectively, the flange 46 exerts a compressive force against both adjoining surfaces of the corner 42 of the flange 38. Thus, a first component of the compressive force is exerted against the undersurface of the flange 38. A second component of the compressive force acts against the ridge 40, urging the flange 38 inwardly toward the bottom of the slot 44. This compressive force, together with the friction generated between contacting surfaces of the flange 46, flange 38, and sidewall of the slot 44, firmly secures the flange 38 in place to maintain the connector in the second configuration.
If it should become necessary at some point to unflex (straighten) the connector 10, it is possible to exert a firm force on the arms 12 and 14 to disengage the flange 38 from the slot 44. The obtuse angling of the corners 48 and 42 of the flanges 46 and 38, respectively, allows disengagement of the connector without requiring excessive force or destruction of any portion of the connector. Tests have shown that the force necessary to disengage the flange 38 from the slot 44 is substantially the same as the force initially required to insert the flange into the slot. Thus, the corner connector may be reused after it is disengaged.
Although the first and second arms 12 and 14 and flexible hinge 15 may be assembled from separate components, it is most economical to form the connector from a single integral piece of material, such as a plastic. Polyamide plastics are well suited for this application, having the necessary stiffness and resiliency properties.
One of ordinary skill in the art will be able to effect various changes, alterations and substitutions to the description of the preferred embodiment above, without departing from the broad concepts of the disclosed invention. It is therefore intended that the scope of Letters Patent granted hereon be limited only by the definition contained in the appended claims and the equivalents thereof. | A corner connector (10) for connecting adjacent first and second spacer sections (20, 22), to form an insulated panel spacer frame includes a first arm (12) joined by a flexible joint (15) to a second arm (14). The second arm includes a recess (44) adjacent the joint, and a deformable projection (46) projecting from an edge of the open face of the recess inwardly toward the bottom of the recess. The first arm includes a securement projection (38) protruding from adjacent the joint (15) that is receivable within the recess of the second arm alongside the deformable projection. The deformable projection is deformed by the securement projection and exerts a compressive force on the securement projection to releasably secure the first and second arms in a desired angular orientation. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to selected 5-hydrazono-3-trichloromethyl-1,2,4-thiadiazoles and their use as foliar fungicides.
2. Description of the Prior Art
Various 3,5-disubstituted-1,2,4-thiadiazole compounds have been known to possess different types of pesticidal activity such as fungicidal, herbicidal, insecticidal, nematocidal, and the like. For example, U.S. Pat. No. 3,324,141, which issued to Jack Bernstein on June 6, 1967, discloses that various 5-amino or hydrazino-3-trichloromethyl-1,2,4-thiadiazoles are useful as soil fungicides.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to, as compositions of matter, selected 5-hydrazono-3-trichloromethyl-1,2,4-thiadiazole compounds of the formula: ##STR2## wherein R is a lower alkyl having 1 to 4 carbon atoms, phenyl, and a substituted phenyl, in which the phenyl ring substituents are selected from lower alkyl having 1 to 4 carbon atoms, lower alkoxy having 1 to 4 carbon atoms, halo such as fluoro, chloro, bromo, iodo, hydroxy, nitro, and mixtures thereof; R' and R" are individually selected from hydrogen and lower alkyl having 1 to 4 carbon atoms. The present invention is also directed toward the use of these compounds as foliar fungicides.
DETAILED DESCRIPTION
The 5-hydrazone compounds of the present invention may be prepared by reacting the corresponding 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole with a reactive carbonyl compound (e.g., a ketone or aldehyde). This general reaction is illustrated by the following Equation (A) wherein 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole is reacted with acetone: ##STR3##
Suitable 3-trichloromethyl-1,2,4-thiadiazole compounds which could be utilized as precursors for the compounds of the present invention include, besides 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole, mentioned above, the following: 5-(1-methylhydrazino)-3-trichloromethyl-1,2,4-thiadiazole; 5-(1-ethylhydrazino)-3-trichloromethyl-1,2,4-thiadiazole; 5-(1-isopropylhydrazino)-3-trichloromethyl-1,2,4-thiadiazole; 5-(1-n-propylhydrazino)-3-trichloromethyl-1,2,4-thiadiazole; 5-(1-n-butylhydrazino)-3-trichloromethyl-1,2,4-thiadiazole.
The preparation of 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole is described in U.S. Pat. No. 3,324,141 and is made by reacting 5-chloro-3-trichloromethyl-1,2,4-thiadiazole with hydrazine. These latter two compounds are well known. The 5-substituted hydrazino precursors can be made analogously by reacting 5-chloro-3-trichloromethyl-1,2,4-thiadiazole with the desired substituted hydrazine (i.e., R"HN-NH 2 ).
Suitable reactive carbonyl compounds which can be used as reactants include aldehydes such as acetaldehyde, propionaldehyde, butyraldehyde, 2-methylpropionaldehyde, pivaldehyde, isovaleraldehyde, benzaldehyde, salicylaldehyde, o-anisaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, q-nitrobenzaldehyde, o-tolualdehyde, and 3,4-dichlorobenzaldehyde; and ketones such as acetone, 2-butanone, 3-pentanone and acetophenone. Such aldehydes and ketones are generally available commercially.
Any conventional reaction conditions designed to produce hydrazone compounds may be employed in the synthesis of the present compounds and the present invention is not intended to be limited to any particular reaction conditions. Advantageously and preferably, the reactions are performed with an equimolar amount of the carbonyl compound and the 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole compound and in the presence of a suitable inert solvent. However, the use of a solvent is only desirable, but not necessary. The reaction temperature and time will both depend upon many factors including the specific reactants used. In most situations, reaction temperatures can advantageously be from about 30° C. to about 100° C. and reaction times from about 0.5 to about 5 hours may be preferred. The product my be recovered from the reaction mixture by any conventional means, for example, filtration, extraction, slurrying with solvent, recrystallization or the like.
It should be noted that while the reaction illustrated by Equation (A) is a preferred method for preparing the compounds of the present invention, other synthetic methods may also be employed.
Several representative compounds of the present invention are included in Table I which follows:
TABLE I__________________________________________________________________________ Name of CarbonylNo. R R' R" Name of Compound Precursor__________________________________________________________________________1 CH.sub.3 H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- acetaldehyde 2-ethylidenehydrazine2 CH.sub.2 CH.sub.3 H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- propionaldehyde 2-(1-propylidene)hydrazine3 CH.sub.2 CH.sub.2 CH.sub.3 H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- butyraldehyde 2-(1-butylidene)hydrazine4 CH(CH.sub.3).sub.2 H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- 2-methylpropion- 2-[1-(2-methylpropylidene)]hydrazine aldehyde5 C(CH.sub.3).sub.3 H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- pivaldehyde 2-[1-(2,2-dimethylpropylidene)]hydrazine6 CH.sub.2 CH(CH.sub.3).sub.2 H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- isovaleraldehyde 2-[1-(3-methylbutylidene)]hydrazine7 0-chlorophenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- o-chlorobenz- 2-o-chlorobenzylidenehydrazine aldehyde8 m-chlorophenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- m-chlorobenz- 2-m-chlorobenzylidenehydrazine aldehyde9 p-chlorophenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- p-chlorobenz- 2-p-chlorobenzylidenehydrazine aldehyde10 o-nitrophenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- o-nitrobenz- 2-o-nitrobenzylidenehydrazine aldehyde11 o-methylphenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- o-tolualdehyde 2-o-methylbenzylidenehydrazine12 o-methoxyphenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- o-anisaldehyde 2-o-methoxybenzylidenehydrazine13 3,4-dichlorophenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- 3,4-dichlorobenz- 2-(3,4-dichlorobenzylidene)hydrazine aldehyde14 phenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- benzaldehyde 2-benzylidenehydrazine15 o-hydroxyphenyl H H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- salicylaldehyde 2-salicylidenehydrazine16 CH.sub.3 CH.sub.3 H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- acetone 2-isopropylidenehydrazine17 CH.sub.2 CH.sub.3 CH.sub.2 CH.sub.3 H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- 3-pentanone 2-(3-pentylidene)hydrazine18 phenyl CH.sub.3 H 1-(3-trichloromethyl-1,2,4-thiadiazol-5-yl)- acetophenone 2-(1-phenethylidene)hydrazine19 CH.sub.3 CH.sub.3 CH.sub.3 1-methyl-1-(3-trichloromethyl-1,2,4-thiadiazol- acetone 5-yl)-2-isopropylidenehydrazine20 CH.sub.3 H CH.sub.3 1-methyl-1-(3-trichloromethyl-1,2,4-thiadiazol- acetaldehyde 5-yl)-2-ethylidenehydrazine21 phenyl CH.sub.3 CH.sub.3 1-methyl-1-(3-trichloromethyl-1,2,4-thiadiazol- acetophenone 5-yl)-2-(1-phenylethylidene)hydrazine22 o-hydroxyphenyl H CH.sub.3 1-methyl-1-(3-trichloromethyl-1,2,4-thiadiazol- salicylaldehyde 5-yl)-2-salicylidenehydrazine__________________________________________________________________________
Also in accordance with the present invention, it has been found that the compounds of Formula I, above may be utilized as effective foliar fungicides. In practicing the process of the present invention, fungi are contacted with a fungicidally effective amount of one or more of these compounds. It is to be understood that the term "fungicidally effective amount" as used in the specification and claims herein is intended to include any amount that will kill or control said foliar fungi when either employed by itself (i.e., in full concentration) or in sufficient concentrations with a carrier or other substance. Of course, this amount may be constantly changing because of the possible variations in many parameters. Some of these may include: the number and type of fungi to be controlled or killed; the type of media to which the present compound can be applied (e.g., seedlings or fully grown plants); degree of effectiveness required; and type of carrier, if any. Generally speaking, applications of an aqueous spray containing at least about 5, more preferably in the range of about 30 to 300, parts per million of the chemical of the present invention may give satisfactory fungi control.
This step of contacting may be accomplished by applying this compound to the fungi themselves, their habitat, dietary media such as vegetation, crops and the like, including many which these pests may attack.
The above-mentioned compounds of the present invention may be formulated and applied by any conventional methods that include using the compound alone or with a carrier or other substances which may enhance the effectiveness of the chemical or facilitate handling. Moreover, the activity of the present compound may be broadened by the addition thereto of other known pesticides such as other fungicides, herbicides, insecticides and the like.
Specific methods of formulating and applying these active compounds include applying them in the form of dusts, dust or emulsion concentrates, wettable powders and concentrates, granulates, dispersions, sprays, solutions and the like.
The dusts are usually prepared by simply grinding together from about 1% to about 15% by weight of the active compound with a finely divided inert diluent such as walnut flour, diatomaceous earth, fullers earth, attaclay, talc or kaolin. Dust concentrates are made in similar fashion excepting that about 16% to about 75% by weight of active compound is ground usually together with the diluent. In practice, dust concentrates are then generally admixed at the site of use with more inert diluent before it is applied to the plant foilage, soil, or animals which are to be protected from fungi attack.
Wettable powders are generally prepared in the same manner as dust concentrates, but usually about 1% to about 10% by weight of a dispersing agent, for example, an alkali metal lignosulfonate and about 1% to about 10% of a surfactant, such as a non-ionic surfactant, are incorporated in the formulation. For application to agronomic crops, shrubs, ornamentals and the like, the wettable powder is usually dispersed in water and applied as a spray.
Emulsifiable liquids may be prepared by dissolving the active compound in an organic solvent, such as xylene or acetone, and admixing the thus formed solution with a surfactant or an emulsifier. The emulsified liquid is then generally dispersed in water for spray or dip application.
It is possible to formulate granulates whereby the active compound is dissolved in an organic solvent and the resulting solution is then applied to a granulated mineral or the like (e.g., bentonite, SiO 2 , or the like) followed by evaporating off the organic solvent. Granulates can also be obtained by the compacting of the carrier material with the active substance and then reducing this compacted material in size.
Furthermore, the applied formulations of the present invention include other liquid preparations such as dispersions, sprays or solutions. For these purposes, the above-mentioned active compound is normally dissolved in a suitable organic solvent, solvent mixtures or water. As organic solvents, it is possible to use any suitable aliphatic or aromatic hydrocarbon or their derivatives. It is preferred that the solvent be odorless and moreover, be inert to the active compound.
It should be clearly understood that the fungicide formulations, the ingredients which may make up such formulations other than the active compound, the dosages of these ingredients, and means of applying these formulations may include all known and conventional substances, amounts and means, respectively, that are suitable for obtaining the desired fungicidal result. And, therefore, such process parameters are not critical to the present invention.
Fungicides of the present invention may be effective for the control of the broad class of foliar fungi. Specific illustrations of foliar fungi wherein fungicidal activity has been shown include bean rust and cucumber anthracnose.
The following examples further illustrate the present invention. All parts and percentages employed therein are by weight unless otherwise indicated. Yields given are percent molar yields.
EXAMPLE 1
1-(3-Trichloromethyl-1,2,4-thiadiazol-5-yl)-2-Isopropylidenehydrazine
A mixture of 5 ml (3.9 g, 0.068 mole) acetone and 2.4 g (0.01 mole) 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole was heated 0.5 hour on a steam bath. The solid that was left after evaporation of the excess acetone was recrystallized from ligroin to yield 0.95 g (mp. 75°-77° C.). A second crop of 1.2 g (mp. 66° C.) was obtained after concentration of the solvent. Total yield was 2.15 g (79% yield).
The structure was confirmed via infrared and elemental analysis.
______________________________________Analysis for C.sub.6 H.sub.7 N.sub.4 Cl.sub.3 S C H N Cl S______________________________________Calculated: 26.34 2.58 20.48 38.88 11.79Found: 26.26 2.59 20.65 38.68 11.55______________________________________
EXAMPLE 2
1-(3-Trichloromethyl-1,2,4-thiadiazol-5-yl)-2-(1-Phenethylidene)hydrazine
A mixture of 1.2 g (0.01 mole) acetophenone, 2.4 g (0.01 mole) 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole, 1 ml hydrochloric acid (conc.), and 100 ml ethanol was heated 5 hours on a steam bath. Water was added and the solution stored in a freezer several days. The resulting solid was removed by filtration to give 2.5 g (73% yield). An analytical sample (mp. 135°-136° C.) was prepared by recrystallization from toluene.
The structure was confirmed via infrared and elemental analysis.
______________________________________Analysis for C.sub.11 H.sub.9 N.sub.4 Cl.sub.3 S C H N Cl S______________________________________Calculated: 39.36 2.70 16.69 31.69 9.55Found: 39.23 2.75 16.80 31.88 9.28______________________________________
EXAMPLE 3
1-(3-Trichloromethyl-1,2,4-thiadiazol-5-yl)-2-Salicylidenehydrazine
A mixture of 1.3 g (0.01 mole) salicylaldehyde, 2.4 g (0.01 mole) 5-hydrazino-3-trichloromethyl-1,2,4-thiadiazole, 1 ml hydrochloric acid (conc.), and 100 ml ethanol was heated 5 hours on a steam bath. Water was added and the solution cooled in a freezer several days. The resulting solid was removed by filtration to give 2.8 g (83% yield) (mp. 204°-205° C.).
The structure was confirmed via infrared and elemental analysis.
______________________________________Analysis for C.sub.10 H.sub.7 N.sub.4 Cl.sub.3 SO C H N Cl S______________________________________Calculated: 35.57 2.09 16.60 31.51 9.50Found: 35.48 2.19 16.43 31.50 9.25______________________________________
EXAMPLE 4
1-Methyl-1-(3-Trichloromethyl-1,2,4-thidiazol-5-yl)-2-Salicylidenehydrazine
A mixture of 2.50 g (0.01 mole) 5-(1-methylhydrazino)-3-trichloromethyl-1,2,4-thiadiazole and 1.30 g (0.01 mole) salicylaldehyde was stirred. An exothermic reaction ensued and the reaction mixture warmed to 37° C. After 15 minutes ethanol was added and the solid product extracted. The product crystallized and was filtered to yield 2.15 g (61% yield) [mp. 207°-209° C. (dec)].
The structure was confirmed via infrared and elemental analysis.
______________________________________Analysis for C.sub.11 H.sub.9 N.sub.4 Cl.sub.3 SO C H N Cl S______________________________________Calculated: 37.57 2.58 15.93 30.25 9.12Found: 37.85 2.55 16.15 30.57 8.89______________________________________
FOLIAR FUNGICIDE SCREEN
The active materials formed in Examples 1, 2, 3 and 4 were then tested for activity as effective fungicides.
A uniform aqueous dispersion of each chemical made in the above examples was first prepared. These dispersions were made by dissolving each chemical in a solution of acetone containing the surfactant TRITON X-155 1 (500 parts per million). Next, this solution was diluted with water (1:9) to obtain a stock solution of 10% by volume acetone and 90% by volume water with 50 ppm TRITON X-155 and the test chemical contained therein. This stock solution was diluted further with water/acetone mix to provide the desired concentration of the test material, if required.
The aqueous solutions containing each chemical were applied to various plants according to the methods stated below. These tests were designed to evaluate the ability of the chemical to protect non-infected foliage and eradicate recently established infection against major types of fungi such as rust and anthracnose that attack above-ground parts of plants.
BEAN RUST
In primary screening, Pinto beans, which were in 21/2 inch pots and 9 to 12 days old, were sprayed while rotating the plants on a turntable with an aqueous solution of each chemical of Examples 1, 2, 3 and 4. The aqueous solutions contained 260 parts per million of each active chemical. Simultaneously, the soil in each pot was drenched with aqueous solutions of each chemical in the amount of 25 lb./acre. After the spray deposit had dried, the plants were atomized with a suspension of uredospores [summer spore stage of bean rust (Uromyces phaseoli)] and placed in a moist chamber at 70° F. for 24 hours. After 7 days, the severity of pustule formation was rated on a scale of 0 (no inhibition) to 10 (complete inhibition). See Table II for the results of these tests.
In secondary screening, the same spraying and drenching procedures were followed, except lower concentrations were employed and the spraying and drenching was done separately. After each spraying or drenching, the plants were again atomized with a suspension of uredospores and tested for severity of pustule formation in the same manner. These results are also shown in Table II. The compound of Example 3 was the only one subjected to secondary screening against bean rust.
TABLE II__________________________________________________________________________FUNGICIDAL ACTIVITY AGAINST BEAN RUSTPrimary screening Secondary Screening 25 lb/acre drench 12.5 lb/acre 6.3 lb/acre 3.2 lb/acre 130 ppm 65 ppm 33 ppmCompound & 260 ppm spray drench drench drench spray spray spray__________________________________________________________________________Example 1 10 -- -- -- -- -- --Example 2 10 -- -- -- -- -- --Example 3 10 6 8 6 10 10 10Example 4 4 -- -- -- -- -- --__________________________________________________________________________
CUCUMBER ANTHRACNOSE
For the primary and secondary screening, two week old cucumber plants were atomized with a suspension of cucumber anthracnose spores (Collectrotrichium lagenarium) and placed in a moist chamber at 70° F. for 24 hours. In the primary screening, the young plants were then sprayed while rotating the plants on a turntable with an aqueous solution that contained 260 parts per million by weight of the active chemicals of Examples 1, 2, 3 and 4. Simultaneously, the soil in each pot was drenched with aqueous dispersions of each chemical in the amount of 25 lb/acre. After 5 days, the severity of pustule formation was rated on a scale of 0 (no inhibition) to 10 (complete inhibition). See Table III for the results of these tests.
The same procedure was followed with the compound of Example 3 for secondary screening except lower concentrations of that chemical were employed and the spraying and drenching were separated. See Table III for the results of the secondary screening.
TABLE III__________________________________________________________________________FUNGICIDAL ACTIVITY AGAINST CUCUMBER ANTHRACNOSEPriimary Screening Secondary Screening 25 lb/acre drench 12.5 lb/acre 6.3 lb/acre 3.2 lb/acre 130 ppm 65 ppm 33 ppmCompound & 260 ppm spray drench drench drench spray spray spray__________________________________________________________________________Example 1 2 -- -- -- -- -- --Example 2 6 -- -- -- -- -- --Example 3 9 0 0 0 10 10 9Example 4 4 -- -- -- -- -- --__________________________________________________________________________ | Disclosed are selected 5-hydrazono-3-trichloromethyl-1,2,4-thiadiazole compounds of the formula: ##STR1## wherein R is a lower alkyl having 1 to 4 carbon atoms, phenyl, and substituted phenyl in which the said phenyl ring substituents are selected from lower alkyl having 1 to 4 carbon atoms, lower alkoxy having 1 to 4 carbon atoms, halo, hydroxy, nitro and mixtures thereof; and R' and R" are individually selected from hydrogen and lower alkyl having 1 to 4 carbon atoms. These compounds are shown to have foliar fungicidal activity. | 0 |
BACKGROUND OF THE INVENTION
The present invention generally relates to fixed leg platforms used in relatively shallow water for producing mineral resources, specifically oil and gas. The present invention more specifically relates to various embodiments of an apparatus and a method of installing an apparatus which protects wellheads from being struck from objects or equipment which may fall and impact the wellhead and production processing equipment.
Offshore hydrocarbon production in federal waters is regulated by the Minerals Management Service (the “MMS”). The MMS currently requires that wells be shut-in during various operations, including operations to install a drilling or work-over rig on the platform. Specifically, the applicable regulations require that all producing wells in the affected wallaby be shut in below the surface and at the wellhead when a drilling rig is moved between wells on the platform. The regulation also requires that wells be shut-in during rigging up and rigging down activities which occur within 500 feet of the affected platform or when a drilling unit is moved between wells on a platform or when a mobile offshore drilling unit moves within 500 feet of a platform.
This regulation recognizes that many heavy components are lifted over the wallaby and over the wellheads and production piping therein during the mobilization and moving of a drilling rig, presenting the risk that a heavy component may be dropped onto the production piping of a wellhead resulting in damage to the facilities and the possible release of hydrocarbons. The regulation further provides that once enough of the drilling rig, such as the superstructure, is over the well of interest, the wells may be returned to production. However, for a variety of reasons, the moving of a drilling rig may be delayed, resulting in a prolonged period that one or more producing wells are shut-in. For example, in rough seas the work boat transporting rig components may be delayed while waiting for smoother seas to deliver the components to the platform.
Shutting in producing wells is problematic for at least two reasons. First, production is lost or delayed when wells are shut-in. Bringing the wells back online can be time-consuming and may require substantial supervision to safely return the wells to production. Second, some wells are damaged from being shut-in, and do not always return to their previous flow rates after the wells are returned to production. For example, fine particles may be repositioned within the reservoir rock as a result of ebbing and surging flow associated with stopping and resuming of the production in a well. Loss of production is not only detrimental to the owner of the wells, but it also adversely impacts the royalties received by the federal government.
The MMS regulations grant the MMS District Supervisor some discretion in the shutting in of producing wells. The regulations provide that the MMS District Supervisor may approve departures from the shut-in requirement by making application to the District Supervisor. Among other information, the District Supervisor may consider platform structural data and point load calculations showing that the production process systems can withstand the impact of a dropped object. The District Supervisor may also consider a lift sequence plan which describes the order of the lifts, and the lift positioning on the platform deck relative to the wallaby areas and production processing equipment.
SUMMARY OF THE INVENTION
The embodiments of the apparatus disclosed herein and the disclosed method provide an alternative for departing from the MMS shut-in requirements by providing an effective structural barrier for the production process systems. Each embodiment is used on a fixed-leg offshore drilling and production platform, where the platform is of the type having one or more wellheads disposed on a production deck. Because there is limited space on a production platform, each wellhead is located in close proximity to the next adjacent wellhead, where the centerlines of the wellheads are usually only a few feet apart from one another. Hydrocarbon fluids, such as oil and gas, are produced through the wellheads and produced into the platform's production process system.
The area immediately adjacent to the wellheads, both laterally and spatially, is known as the wallaby. The wallaby is usually separated from adjacent platform systems by one or more firewalls, which usually extend upwardly from the production deck to the drilling deck. The wellhead production trees and connected piping are contained within the wallaby area.
The platform further comprises a pair of skid beams, herein designated the first skid beam and the second skid beam, which are generally horizontally disposed in parallel relation to one another and disposed above the production deck. The top surface of the skid beams usually extends above the drilling deck for receiving the components of a modular drilling rig or production rig, which are typically erected on a modular substructure attached to the skid beams. A modular drilling rig may be repositioned along the skid beams and along the drilling rig substructure to allow the drilling of additional wells from different locations within the wallaby without completely dismantling the drilling rig.
The level of the platform at which the drilling rig substructure is placed is usually referred to as the drilling deck. The platform usually has a fixed crane which is used for lifting equipment off of supply boats and for repositioning equipment to various locations on the platform. A platform will frequently have a designated area for setting down equipment lifted off of supply boats by the crane. Often this designated area is a portion of the drill deck which is referred to herein as the “wing deck”.
The skid beams may also be used for supporting well maintenance equipment in addition to well drilling equipment. As those skilled in the art are aware, hydrocarbon wells frequently require a rig for well maintenance, such as well clean out, casing repair, replacement of downhole production equipment, additional perforating, well stimulation, or other maintenance operations generally referred to as “work overs.” The substructure of a maintenance rig is typically erected on the skid beams in similar fashion as a modular drilling rig.
An embodiment of an apparatus for protecting the wellhead and other production facilities during mobilization and operation of either well drilling or well maintenance equipment comprises a first support beam which overlays at least a portion of the first skid beam and a second support beam overlaying at least a portion of the second skid beam. The first support beam and the second support beam each have a top surface adapted for receiving either well drilling or well maintenance equipment, such as a drilling rig or a work-over rig. A first cross-member and a second cross-member span between the first support beam and the second support beam, where the first cross-member and second cross-member are generally in parallel relation to one another. Means for securing the ends of the first cross-member and the second cross-member to the first support beam and the second support beam are provided. At least one well cover panel spans between the first cross-member and the second cross-member. The well cover panel comprises a first side end and an opposing second side end. The well cover panel slid ably overlays a portion of the first cross-member and to the second cross-member. The components of the disclosed apparatus have sufficient structural integrity to effectively shield wellheads and the associated production piping from items which may be inadvertently dropped during the relocation or operation of a drilling or work over rig.
The apparatus itself may be assembled in such a manner that none of the components of the apparatus need be lifted directly over the wellheads or production piping, so that shutting in of the wells is not required for installation and placement of the apparatus. Therefore, a method of installing one or more embodiments of the apparatus is disclosed.
An embodiment of the method comprises the steps of disposing a first support beam to overlay at least a portion of the first skid beam and disposing a second support beam in parallel relation to the first support beam, wherein the second support beam overlays at least a portion of the second skid beam. A first cross-member is placed so that it spans between the first support beam and the second support beam. Likewise, a second cross-member is placed so that it also spans between the first support beam and the second support beam. The first cross-member and the second cross-member are installed such that the first cross-member and second cross-member are adapted to slide in parallel relation to one another. A well cover panel is disposed between the first cross-member and the second cross-member, where the well cover panel is adapted to slide across a portion of the length of the first cross-member and a portion of the length of the second cross-member. The first support beam, the second support beam, the first cross-member, the second cross-member, and the well cover panel collectively comprise the wellhead cover assembly. The wellhead cover assembly is slid from a first position overlaying the wing deck to a second position overlaying the well bay. The well cover panel is slid to a position directly overlying the wellhead. Once the well cover panel is in place, the well drilling equipment or the well maintenance equipment may be installed on the platform.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 generally shows a fixed leg platform and how various items, including components of the disclosed apparatus, may be lifted by crane and deposited onto the platform deck.
FIG. 2 schematically shows the disclosed apparatus and an erected modular drilling rig or work-over rig.
FIG. 3A shows a plan view of an embodiment of a wellhead cover assembly for positioning over a number of wellheads.
FIG. 3B shows an lavational view of the embodiment shown in FIG. 3A .
FIG. 4A shows an embodiment of individual well cover panel.
FIG. 4B shows another embodiment of an individual well cover panel.
FIG. 5A shows an lavational view of an embodiment of a cross-member of the disclosed apparatus.
FIG. 5B shows a partial lavational view of a wellhead cover overlying the cross-member of FIG. 5A .
FIG. 6A shows a plan view of an embodiment of the disclosed apparatus.
FIG. 6B shows a detailed view of how the support beams of the apparatus shown in FIG. 6A may be connected together.
FIG. 7A shows a plan view of an embodiment of a wellhead cover assembly for protecting a row of three wellheads.
FIG. 7B shows an lavational view of the embodiment of FIG. 7A
FIG. 8A shows one means of attaching a cross-member to a support member.
FIG. 8B shows a cross-section along line 8 B- 8 B of FIG. 8A .
FIG. 9A shows another means of attaching a cross-member to a support member.
FIG. 9B shows a cross-section along line 9 B- 9 B of FIG. 9A .
FIG. 9C shows a top view of FIG. 9B .
FIG. 10 shows a means of securing the support beams to the skid beams.
FIG. 11A shows a side view of the locking device shown in FIG. 10 .
FIG. 11B shows a front view of the locking device shown in FIG. 10 .
FIG. 12 shows a schematic of a platform deck, showing the wing deck area and the well bay area.
FIG. 13 shows a schematic of an embodiment of the disclosed apparatus being assembled at the wing deck area.
FIG. 14 shows a schematic of an embodiment of the disclosed apparatus after it has been slide into position over the well bay area.
FIG. 15 shows how a leapfrog crane may be positioned in relation to the platform crane to assemble an embodiment of the apparatus.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Referring now specifically to the drawings, FIG. 1 generally shows a production platform 10 . The platform 10 may comprise a drill deck 12 and production deck 14 . The platform may further comprise crane 16 , which may be used, among other things, for offloading materials and supplies from delivery vessels, such as workboat 18 shown in FIG. 1 . For fixed leg production platforms such as that depicted in FIG. 1 , hydrocarbon wells are typically drilled by a drilling rig which is erected on the drill deck 12 . After drilling is initiated for each well, the wellhead for each well is typically located at the production deck 14 . After drilling has been completed for a well, various piping fixtures are attached to its wellhead for receiving oil, gas and other fluids which may be produced from the underlying hydrocarbon reservoir and produced through the wellhead into the platform's production processing system. Usually, separation facilities on the platform separate gas from the liquids and separate water from the oil. Gas and oil may then be shipped off of the platform via pipeline or tanker.
Because combustible fluids are usually produced through the wellheads, the wellheads and attached piping are usually separated from other platform facilities by one or more firewalls 21 . The space in which the wellheads and the attached piping are located is generally referred to as the wallaby 20 . The wallaby 20 commonly extends from the level of the drill deck 12 of the platform down to the level of the production deck 14 , and wellheads 26 in the wallaby are accessed from above by either a drilling rig, work over rig or a wire line unit. Wellheads 26 and firewalls 21 are schematically shown in FIGS. 12 and 13 .
When a modular drilling rig 22 is installed on a production platform 10 , the rig is designed to be positioned or “skid” over to the desired “slot” of the wallaby 20 without dismantling of the rig. As shown in FIG. 2 , a rig 22 can usually be skidded along the length of the platform along the skid beams 28 , 30 . In addition, a rig 22 can usually skid along the width of the platform along substructure beams 31 . The capability of the rig 22 to be moved both length-wise and width-wise above the well bay 20 allows the rig to set up over each wellhead location. Typically, in new well operations, once the rig 22 is over the desired location, the rig will drill an “open hole” to a relatively shallow depth, and surface conductor will be installed and cemented into the open hole. Once the surface conductor is in place, a wellhead is attached to the surface conductor, and blowout preventer equipment attached to the wellhead.
Because of the risks of injury and pollution associated with the uncontrolled release of hydrocarbons, the wellheads and associated piping located in the wallaby 20 must be protected from items which may fall and damage the structural integrity of the wellheads or attached piping. The risk of falling equipment may be greater during operations associated with erecting or moving a modular drilling rig 22 or work over rig on the platform 10 . When a rig 22 is initially erected on a platform 10 , the usual practice is to lift the rig components off of a workboat with crane 16 . Because various rig components are extremely heavy, if the components are dropped onto either a wellhead or associated piping, the structural integrity of those items may be compromised. For this reason, current MMS regulations require that the wells on the platform be closed in at the surface (i.e. at the platform level) as well as being shut-in at the subsurface safety valve during various activities, including erection of a rig and skidding of a rig.
On many platforms, the drill deck 12 adjacent to the well bay 20 comprises removable sections of relatively thin steel plate arranged in a grid pattern, where each section may be removed for accessing the wellhead 26 located below at the production deck 14 . These sections are typically rated at 250 pounds per square foot. However, the removable sections are not typically of sufficient strength to prevent penetration by a heavy falling object, such as a falling drilling rig component. Therefore, these removable sections are generally not sufficient protection for the wellheads and related piping during rig erection or rig skidding operations.
The disclosed apparatus creates a steel shield over the wallaby 20 at approximately the level of the drill deck 12 . This shield should provide an acceptable departure from the MMS requirement that a platform's wells be shut-in during rig erection or skidding operations. In addition, the method of installing the disclosed apparatus itself avoids heavy lifts over the wallaby 20 , such that the wells need not be shut-in during the installation of the apparatus.
On most platforms there is usually open deck space on the drill deck 12 between the first line of wells in the wallaby 20 and the nearest edge of the platform, which is usually sixteen feet or greater. This area of open deck will henceforth be referred as the wing deck 24 . The wing deck 24 is adjacent to the well bay 20 , but does not directly overlie the wellheads 26 and associated piping. Therefore, materials may usually be deposited on the wing deck 24 by the crane 16 without shutting in any wells. Thus, the wing deck 24 is often used by the crane operator for setting down materials and supplies delivered to the platform by boat 18 . The wing deck 24 may also be used for gathering and assembling the components of the disclosed wellhead protection apparatus.
As shown in FIG. 1 and explained in greater detail below, the platform crane 16 may be used to offload components of the apparatus from workboat 18 and set those components down on the wing deck 24 . Once on the wing deck 24 , an embodiment of the apparatus may be assembled and then—with the assistance of the crane, winch, or jacks—slid over the wellheads 26 located in the wallaby 20 . Alternatively, as explained below, pre-assembled components of the apparatus may be delivered to the platform 10 , placed on the wing deck 24 , and likewise positioned over the wellheads 26 .
The apparatus is constructed using existing platform skid beams 28 , 30 . The skid beams 28 , 30 are generally disposed in parallel relation to one another as shown in FIG. 1 . The skid beams 28 , 30 may be several feet in height and the flanges on each side of the beams may have a width of over twenty inches. The top flange 29 of each skid beam 28 , 30 generally extends above the drill deck 12 . The skid beams are usually supported by the platform legs 33 as shown in FIG. 3 b . On most fixed leg platforms, the skid beams 28 , 30 are used for installing the components of a modular drilling rig 22 . As discussed below, the top flange 29 of the skid beams 28 , 30 generally has a plurality of longitudinal slots which may be utilized for moving and securing rig components to the skid beams.
One embodiment of the protection apparatus comprises a first support beam 32 which overlays at least a portion of the first skid beam 28 as generally depicted in FIG. 3A . Likewise, a second support beam 34 overlays at least a portion of the second skid beam 30 . The support beams 32 , 34 may either comprise single beam lengths as depicted in FIG. 3A , or may comprise a plurality of beam lengths assembled together as depicted in FIG. 6A .
The first support beam 32 and the second support beam 34 serve as foundational supports for the rig 22 instead of skid beams 28 , 30 , so the first support beam and the second support beam each have top surfaces, including slots configured as those in the skid beams, such that the first support beam and the second support beam are adapted to receive modular components of either a drilling rig, work over rig, or other well maintenance equipment. The apparatus further comprises a first cross-member 36 and a second cross-member 38 spanning between the first support beam 32 and the second support beam 34 , the first cross-member and second cross-member in general parallel relation to one another.
At least one well cover panel 40 spans between the first cross-member 36 and the second cross-member 38 . The well cover panel 40 may be configured to slid ably overlay the first cross-member 36 and the second cross-member 38 , as shown in FIG. 7A . Utilizing the crane 16 , jacks, winch, or other known mechanical means, well cover panel 40 may be slid or lifted along cross-members 36 , 38 to expose and allow access to the wellhead located beneath the panel.
FIG. 7A also shows how the apparatus may be assembled on a sectional basis to form a wellhead cover assembly 42 . The wellhead cover assembly comprises first support beam 32 ′, second support beam 34 ′, first cross-member 36 , second cross-member 38 , and one or more well cover panels 40 . As further shown in FIG. 7A , the well cover panel may slid ably overlay the first cross-member 36 and to the second cross-member 38
As shown in FIGS. 4A and 4B , a well cover panel comprises a first side 43 and an opposing second side 44 . The well cover panel 40 may further comprise opening 45 which would allow limited access to the wellhead beneath the panel. For example, wire line operations might be conducted through opening 45 without the need for removing the entire well cover panel 40 . Well cover panel 40 may further comprise cover 47 adapted to fit over and close opening 45 . The well cover panel may further comprise a first slide member 46 which overhangs the side of the first cross-member 36 , as depicted in FIG. 5B .
As shown in FIG. 5B , first cross-member 36 may comprise a drain 48 attached to the side of the first cross-member. First slide member 46 may be disposed inward of the drain as shown in FIG. 5B . The drain 48 may catch rain, seawater, rinse water, or effluent of drilling mud, oil, etc., diverting the liquids to a deck drain, separator, or other desired location. The well cover panel 40 may also comprise raised edge 49 . The raised edge 49 would act to channel any liquids to drain 48 . Cross-members 36 , 38 may be disposed between the support beams 32 , 34 , such that the cross-members have a slightly higher elevation at the center of the span of the cross-members to improve drainage away from the center of the wallaby 20 .
It is to be appreciated that an embodiment of the disclosed apparatus may be constructed using a variety of different steps. For example, if support beams 32 , 34 are previously attached to the skid beams 28 , 30 , first cross-member 36 and the second cross-member 38 may be slid between the support beams from the wing deck 24 to a location overlying the wallaby 20 . This step may be modified by previously attaching connecting members 50 between cross-members together so that the cross-members 36 , 38 may be slid as a unit between the support beams 32 , 34 with the cross-members maintained in parallel relation to one another. Upon being slid to the desired location, the ends of the first cross-member 36 and the second cross-member 38 are secured to the first support beam 32 and the second support beam 34 . The ends may be fastened with conventional fastening means, such as welding or bolting.
FIGS. 8A , 8 B, 9 A and 9 B show different means for attaching the ends of the cross-members 36 , 38 to support beams 32 , 34 . For example, as an alternative to welding the ends of the cross-members 36 , 38 to support beams 32 , 34 , the ends 52 of a cross-member may be adapted, as shown in FIG. 8B , to abut the support beam and fastened to a fastener flange 54 with fastener 55 . Fastener flange 54 is attached to the support beam 32 , 34 . The ends 52 of the cross-member 36 , 38 may be tapered as shown in FIG. 8B . As shown in FIG. 5B , support beams 32 , 34 may have guide 57 attached to the side of each beam to assist in aligning the support beams with the respective skid beams 28 , 30 upon which the support beams will lay.
Alternatively, as shown in FIG. 9B , the ends 52 ′ of a cross-member 36 ′, 38 ′ may comprise a tapered end 56 which either has pin 58 attached to or set through the tapered end. Pin 58 is set within receiving flange 60 attached to support beam 32 ′, which may be formed in an upwardly facing “U” as shown in FIG. 9B for ease of connecting cross-member 36 ′, 38 ′ to support beam 32 ′. Of course, the materials and diameter of pin 58 should be selected as required to support the distributed weight of the apparatus and the impact loads which the apparatus might be expected to receive. Pin 58 may either be welded to tapered end 56 , or inserted in or through an opening in tapered end 56 .
It is to be appreciated that the embodiment shown in FIG. 9B , as compared to the embodiment shown in FIG. 8B , will raise the bottom of the support beams 32 ′, 34 ′ higher off of the drill deck 12 , which allows the support beams to bend more before impacting the drill deck. For example only, a W14×109 beam impacted by a 15,000 pound load dropped from a height of twenty-four inches may cause the beam to be deflected approximately seven to eight inches at the center of the beam.
Support beams 32 , 34 are to be sized according to the loading requirements of rig 22 , and would typically be a W24×104 beam. Cross-members 36 , 38 would typically be W14×109 beams. The well panels 40 should be of sufficient strength to resist a 20,000 load over an area of 100 ft 2 if dropped from a height of 2 feet above the panel. Therefore, the weight of the components of the apparatus will require that each component is set into place with mechanical assistance in the form of either the platform crane 16 , leapfrog crane 17 , the use of hydraulic or mechanical jacks, winches or other such devices known in the art.
The choice of fastening means for attaching support beams 32 , 34 to the skid beams 28 , 30 and for attaching the cross-members 36 , 38 to the support beams 32 , 34 is dependent upon the particular platform design, with the object of eliminating or minimizing the lifting of heavy members and components over the wallaby 20 . Support beams 32 , 34 may be single length beams which are attached to skid beams 28 , 30 before other components of the apparatus are installed. The support beams 32 , 34 may be attached to the skid beams 28 , 30 by known means of connecting two I-beams flange to flange, including welding, threaded fasteners or other known means.
Alternatively, the cross-members 36 , 38 may be attached to a plurality of support beams 32 ′, 34 ′ which are attached to one another end-to-end as indicated on FIGS. 6A , 6 B, and 7 A. In this embodiment, the support beams 32 ′, 34 ′ are in short sections, such as three to four feet. As shown in FIG. 7A , the ends of each support beam 32 ′ 34 ′ may be configured to have a male end 35 or a female end 37 , where the female end has a narrowed opening preventing the withdrawal of a larger portion of the male connector. As shown in FIG. 6A , these connectors allow the support beams to be locked together on an end-to-end basis by lowering the male end 35 into the female end 37 , or lowering the female end over the male end. This feature allows a plurality of assembled wellhead cover assemblies 42 to be individually placed into position on skid beams 28 , 30 , but once placed into position, the wellhead cover assemblies may be locked together as shown in FIG. 6A . The support beams 32 ′, 34 ′ may also be attached end-to-end by other known fastening means such as threaded fasteners and welding.
Because an assembled wellhead cover assembly 42 may be slid along the skid beams 28 , 30 by either a crane (in combination with block and tackle), jacks, or other mechanical means, as opposed to lifting the wellhead cover assembly over the wallaby 20 , the apparatus may be installed without making any crane lifts over the wallaby. The wellhead cover assemblies 42 may be assembled at a site remote from the platform and delivered by workboat 18 in an assembled configuration as indicated on FIG. 1 . The completed assemblies may then removed from the work boat 18 by either the platform crane 16 or a leapfrog crane 17 , and set upon wing deck 24 or other location at which the lift may be made without swinging a load over the wallaby 20 . Depending upon the location of the wing deck(s) 24 of the platform and the reach of the platform crane 16 , it may be necessary to utilize a leapfrog crane 17 to place the wellhead cover assembly 42 at the desired location. Alternatively, the wellhead cover assemblies 42 may be assembled entirely on the platform, such as on the wing deck 24 , and placed in position as discussed above.
Once a wellhead cover assembly 42 is placed at the desired location along the skid beams 28 , 30 , the support beams 32 ′, 34 ′ are fastened to the skid beams. Conventional fastening means, such as welding and threaded fasteners may be used for this purpose. Alternatively, a temporary locking device may be used, which facilitates attachment and detachment of the support beams 32 ′, 34 ′ from the skid beams 28 , 30 . The skid beams 28 , 30 usually have a series of slots 62 in the top flange 29 . The slots 62 are generally used for attaching and skidding modular rig components to the skid beams 28 , 30 . The slots generally have dimensions of approximately two inches in width by six inches in length. As shown in FIG. 10 , slots 62 may be used in conjunction with a generally corresponding and overlapping slot 64 in the bottom flange 66 of support beam 32 ′. Slide lock 68 may then be used to lock support beam 32 ′ to skid beam 28 by inserting the bottom member 70 through both slot 62 and slot 64 and then sliding the lock such that bottom flange 66 and top flange 29 are sandwiched between the extended portion of bottom member 70 and the extended portion of top member 72 of the slide lock.
It is to be appreciated that because support beams 32 , 34 (and 32 ′, 34 ′) will take the place of the skid beams 28 , 30 for contact with the substructure of drilling rig 22 , the support beams may also have a series of slots 62 ′ in the top flange similar to the slots 62 in the skid beams to accommodate the installation and skidding of the rig components.
FIGS. 12 through 14 generally show the sequence of how assembled wellhead cover assemblies may be placed on the wing deck 24 and then slide into place over the well bay 20 . FIG. 15 shows how a leapfrog crane 17 may be positioned to lift materials of a workboat 18 in the event the platform crane 16 does not have sufficient reach to lift the materials off of the boat and place the materials at the wing deck 24 .
While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. For example, the size, shape, and/or material of the various components may be changed as desired. Thus the scope of the invention should not be limited by the specific structures disclosed. Instead the true scope of the invention should be determined by the following claims. | An apparatus and method for protecting wellheads of a fixed-leg drilling and production platform which provide an alternative from the shutting in of producing wells as currently required. The apparatus provides a structural barrier for the production process systems of the platform, shielding such systems from heavy objects which may be dropped in the course of rig mobilization and skidding procedures. A method of installing an embodiment of the apparatus allows the barrier to be installed without shutting in the production wells. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for preventing and eradicating plant disease caused by bacterial infection and, more particularly, it relates to a plant disease prevention and eradication method which comprises applying a composition containing, as an effective component, a 4(1H)-oxo-3-quinolinecarboxylic acid derivative.
2. Description of the Prior Art
Recently, many new organic synthetic fungicides have been discovered as plant disease preventing agents and they have largely contributed to an increased production of foods. However, although they are effective for diseases caused by fungi, they are ineffective for bacterially caused diseases. Except for a few antibiotics (e.g., streptomycin, novobiocin, chloramphenicol, etc.) which have a narrow applicable range, chemical compositions exhibiting specific activities to bacterially caused plant diseases have not yet been developed.
SUMMARY OF THE INVENTION
On considering the importance of the prevention and eradication of bacterially caused diseases of agricultural and horticultural crops, various investigations have been made for the purpose of developing compositions for preventing bacterially caused plant diseases and, as the result thereof, it has now been discovered that the compounds represented by the general formula (I) below have a strong systemic activity in plants and a surprisingly excellent effect in the prevention and the eradication of these bacterially caused diseases of plants. Furthermore, it has also been found that the compounds of this invention do not adversely affect agricultural and horticultural crops.
Thus, according to the present invention, there is provided a method for preventing and eradicating plant diseases which comprises applying a composition containing, as an effective component, at least one 4(1H)-oxo-3-quinolinecarboxylic acid derivative represented by the general formula (I): ##STR3## wherein A represents --OCH 2 O--(attached to the 6 and 7 position) or ##STR4## (attached to the 6 and 5 position), wherein R 4 represents a hydrogen atom or a (C 1 -C 4 )alkyl group; R 1 represents a hydrogen atom, a (C 1 -C 4 )alkyl group, an amino group, an ammonium group or an alkali metal atom; R 2 represents a (C 1 -C 4 )alkyl group, a halogenated (C 1 -C 4 )alkyl group, a (C 1 -C 4 )hydroxyalkyl group, a (C 2 -C 3 )alkenyl group, or a (C 1 -C 4 )alkoxyl group; and R 3 represents a hydrogen atom or a (C 1 -C 4 )alkyl group. In the above, the alkali metal atom preferably includes sodium and potassium atoms, and the halogenated (C 1 -C 4 )alkyl group preferably includes a (C 1 -C 4 )alkyl group substituted with a fluorine or chlorine atom.
DETAILED DESCRIPTION OF THE INVENTION
Some of the compounds of this invention within the scope of the general formula (I) are already known as antibacterial agents in the medical field as disclosed in, for example, U.S. Pat. No. 3,287,458, Japanese Patent Publication No. 26,638/74, and Japanese Patent Application (OPI) Nos. 31,998/72, 89,396/75 and 43,798/76, which describe the utilization of them as chemotherapeutic agents for animal diseases caused by bacteria. However, none of these references teach or suggest that these compounds could be utilized as agricultural and horticultural eradicants for plant diseases caused by bacterial infection.
As the result of intensive investigations on utilization of various medicines having chemotherapeutic properties as an agent for preventing and eradicating bacterially caused diseases of agricultural and horticultural crops, it has been discovered that only the compounds represented by the general formula (I) have quite excellent effects as such eradicants. Practically speaking, as shown in the test results of Table 2 in Example 1 given hereinafter, nalidixic acid and a sulfa drug such as sulfamine which are widely used for curing a urethral meatus infection and an intestinal infection as well as chlorhexidine which is used for the local prophylaxis of bacterial infections were all observed to have no effect for preventing the occurrence of the soft rot disease of Chinese cabbage caused by Erwinia aroideae, while the compounds of this invention showed an excellent effect superior to the comparison drug, streptomycin-sulfate.
Furthermore, by performing simultaneously an antibacterial test in vitro and a disease prevention test, a quite surprising result was obtained. It was found that Compounds Nos. 2, 8 and 11 in Example 2, which possess very weak antibacterial activity Erwinia carotovora, were observed to be highly effective in preventing and eradicating soft rot disease of Chinese cabbage caused by this bacterium. This fact shows clearly that chemotherapeutical materials used as medicaments cannot always be utilized as compositions for controlling plant diseases.
Moreover, as the result of further investigations of the properties of the compounds used in this invention, it has also been demonstrated that the compounds used in this invention have the property of readily being absorbed in a plant through the roots and translated into the aerial parts of the plant. This property contributes greatly to the antibacterial activity against bacteria which parasitize and propagate inside a plant. Accordingly, systemic action of antibacterial agents in a plant is essential for prevention and eradication of bacterial diseases. The reason that conventional antibacterial materials for medical use show almost no effect on plant disease control when they are practically applied to plants is due to lack of systemic activity in a plant. On the other hand, since the compounds of this invention have a high systemic activity in a plant, in addition to their antibacterial activity, the compounds exhibit quite high efficacy in preventing and eradicating bacterially caused plant diseases. These properties of the compounds only now have been discovered.
The compounds of this invention can be prepared by the processes described in the above-illustrated patent references and Japanese Patent Application (OPI) No. 31,999/72.
Some specific examples of the compounds which can be used in this invention are illustrated in Table 1 below but, as the matter of course, this invention is not to be construed as being limited to these compounds only.
TABLE 1__________________________________________________________________________4(1H)-Oxo-3-quinolinecarboxylic Acid DerivativesCompound PhysicalNo. Chemical Formula Property__________________________________________________________________________(1) ##STR5## m.p. 310° C (decomposition)(2) ##STR6## m.p. 198-199° C(3) ##STR7## m.p. 260° C (decomposition)(4) ##STR8## m.p. 277-278° C(5) ##STR9## m.p. 303-305° C (decomposition)(6) ##STR10## m.p. 327-329° C(7)* ##STR11## m.p. 311-314° C(8)* ##STR12## m.p. 229-230° C(9)* ##STR13## m.p. 279-280° C (decomposition)(10) ##STR14## m.p. 312-315° C (decomposition)(11) ##STR15## m.p. 305° C (decomposition)(12) ##STR16## m.p. more than 300° C (decomposition) 5(13) ##STR17## m.p. more than 300° C (decomposition)__________________________________________________________________________ *Compounds 7,8 and 9 are compounds undisclosed in the prior art.
In the present invention, a method for eradicating plant disease caused by bacterial infection can be carried out by, for example, dusting, spraying or applying a compound of the formula (I) as described above to a plant, mingling it with soil around the plant roots or immersing a plant into a solution or suspension of a compound of the formula (I) so that a compound of the formula (I) comes in contact with the plant.
For this purpose, a compound of the formula (I) can be used alone, but usually it is used in the form of an appropriate agricultural preparation such as dusts, wettable powders, oilsprays, tablets, emusifiable concentrates, granules, fine granules, aerosols and the like.
These agricultural preparations can be prepared in a conventional manner by mixing a compound of the formula (I) with an appropriate solid or liquid carrier and appropriate adjuvants (e.g., surfactants, adherents, dispersants, stabilizers, etc.) for improving the dispersibility and other properties of the compound (I) at use.
Examples of appropriate solid carriers which can be used are a fine powder or granules of a botanical carrier (e.g., flour, tobacco stalk powder, soybean powder, walnut shell powder, wood powder, saw dust, bran, bark powder, cellulose powder, vegetable extract residue, etc.); fibrous materials (e.g., paper, corrugated cardboard and old rags, etc.); synthesized plastic powders; clays (e.g., kaolin, bentonite, fuller's earth, etc.); talcs; other inorganic minerals (e.g., pyrophyllite, sericite, pumice, sulfur powder, active carbon, etc.) and chemical fertilizers (e.g., ammonium sulfate, ammonium phosphate, ammonium nitrate, urea, ammonium chloride, etc.).
Examples of appropriate liquid carriers which can be used are water; alcohols (e.g., methyl alcohol, ethyl alcohol, etc.); ketones (e.g., acetone, methyl ethyl ketone, and the like); ethers (e.g., diethyl ether, dioxane, Cellosolve, tetrahydrofuran, etc.); aromatic hydrocarbons (e.g., benzene, toluene, xylene and methyl naphthalene, etc.); aliphatic hydrocarbons (e.g., gasoline, kerosene and lamp oil, etc.); esters; nitriles; acidamides (e.g., dimethylformamide, dimethylacetamide, etc.); and halogenated hydrocarbons (e.g., dichloroethane, carbon tetrachloride, etc.).
Examples of surfactants which can be used in the present invention are alkyl sulfuric ester alkyl sulfonates, alkylaryl sulfonate, polyethyleneglycol ethers and polyhydric alcohol esters. Examples of adherents and dispersants which can be used in the present invention may include casein, gelatin, starch powder, carboxymethyl cellulose, gum arabic, alginic acid, lignin, bentonite, molasses, polyvinyl alcohol, pine oil and agar. As a stabilizer, use can be made of members such as PAP (isopropyl acid phosphates mixture), TCP (tricresyl phosphate), tolu oil, epoxidized oil, various surfactants and various fatty acids and esters thereof.
Furthermore, if necessary, the compounds of this invention can be used as a mixture thereof with other agricultural chemicals such as fungicides, insecticides, miticides, nematocides, herbicides, plant growth regulators, synergists, etc., or fertilizers and, in this case, all of the components present can be effectively used without reducing the effect of any component.
The particular dosage of the compound (I) used in the present invention will be decided taking into consideration various conditions such as the kind, stage or degree of the disease to be eradicated, the properties of the compound, the growth circumstances of the plant and the like.
Generally speaking, a compound of the formula (I) may be used at a concentration of 10 to 2,000 ppm. For example, in case of field application, 10 to 300 g per 10 are of a compound of the formula (I) may be used at this concentration.
Diseases of agricultural and horticultural crops to which the compounds used in this invention are effective are described below in more detail. That is, the compounds used in this invention exhibit excellent disease prevention effects to many bacterially caused diseases of various crops such as bacterial leaf blight of rice, the soft rot of various vegetables, black rot, bacterial wilt of egg plants, the bacterial canker of tomatoes, angular leaf spot disease of melons, the bacterial canker of tulips, the shot hole of peaches, the wild fire of tobacco, the bacterial canker of citrus fruits, the fire blight of apples and pears, the black leg of potatoes, etc. Also, as is clear from the results shown in the examples described hereinafter, the compounds used in this invention exhibit excellent disease prevention effects not only when dusted or sprayed onto stalks and leaves but also when treated as a soil drench, by root immersion or as a seed dressing.
The invention will further be explained by reference to the following formulation embodiments and examples but the invention is not to be construed as being limited thereto. In addition, the numerical designations for the compounds used as the effective components in the formulation embodiments and the examples correspond to the numerical designations for the compounds shown hereinbefore in Table 1.
(a) Dust
By crushing and mixing well 2 parts by weight of Compound (1) and 98 parts by weight of clay, a powder containing 2% of active ingredient was obtained.
(b) Wettable Powder
By crushing and mixing well 20 parts by weight of Compound (4), 75 parts by weight of diatomaceous earth, and 5 parts by weight of a wetting extender (an alkylbenzenesulfonate), a wettable powder containing 20% of the active ingredient was obtained.
(c) Emulsifiable Concentrate
By mixing 10 parts by weight of Compound (9), 80 parts by weight of dimethyl sulfoxide, and 10 parts by weight of an emulsifying agent (a polyoxyethylene phenylphenol ether), an emulsifiable concentrate containing 10% of the active ingredient was obtained.
(d) Granules
By crushing and mixing well 5 parts by weight of Compound (7), 3.5 parts by weight of clay, and 1.5 parts by weight of a binder (polyvinyl alcohol) and, after kneading with water, granulating the mixture followed by drying, granules containing 5% of the active ingredient were obtained.
The following examples are given to illustrate the effects of the present invention more specifically. Unless otherwise indicated, all parts, percents, ratios and the like are by weight.
EXAMPLE 1
Test for Disease Prevention Effect on Soft Rot of Chinese Cabbage Caused by E. aroideae
Onto Chinese cabbage (Brassica pekinesis Rupr. cr.) grown in a flower pot of a diameter of 9 cm at two-leaf stage, the test sample in a dilute emulsion form was sprayed at a rate of 7 ml per flower pot. Three days thereafter, the leaves of the Chinese cabbage were injured and inoculated with a suspension of E. aroideae. Thereafter, the flower pot was placed in a dark and moist chamber (90-100% RH) for 2 days at 28° C and then incidence of the disease was assessed in the following manner. That is, the severity of disease was calculated according to the following relationship by measuring the ratio of the diseased area of the leaves, classifying the severity into grades 0, 1, 2, . . . 8 depending on the degree of the disease and recording the number of leaves n 0 , n 1 , n 2 . . . n 5 corresponding to the each disease index:
______________________________________Disease Index Ratio of Diseased Area______________________________________0 No disease1 Diseased area: less than 5%2 " 5 to less than 30%4 " 30 to less than 60%8 " 60% or more ##STR18##______________________________________
Two flower pots with two plants in each were used for each treatment. The results obtained are shown in Table 2 below.
TABLE 2__________________________________________________________________________Test Results of Disease PreventionEffect on Soft Rot of Chinese Cabbage Concentra- tion of Severity Active of Ingredient DiseaseCompound (ppm) (%)__________________________________________________________________________ 500 0(1) 100 0 500 0(2) 100 7 500 0(3) 100 9 500 0(4) 100 0 500 0(5) 100 14 500 0(6) 100 0 500 0(7) 100 0 500 0(8) 100 0 500 0(9) 100 0 500 0(10) 100 12 500 0(11) 100 4 500 0(12) 100 0 500 0(13) 100 0 ##STR19## 500 100 ##STR20## 500 100 ##STR21## 500 100Streptomycin Sulfate 200 14Control (no spraying) -- 100__________________________________________________________________________* Reference compounds which have chemotherapeutic activity againstbacterial disease in warm-blooded animals, having antibacterial
EXAMPLE 2
Simultaneous Test for Antibacterial Activity against E. carotovora and Curative Effect on Soft Rot of Chinese Cabbage Caused by E. carotovora
The test compound was mixed with a bacteriological culture medium containing 1.5% agar at various concentrations and the mixture was poured in a Petri dish of a diameter of 8 cm followed by solidifying. 24 hour-culture in a bacteriological culture medium of E. carotovora from a stock culture was diluted 10 times with sterilized water and inoculated on the agar culture medium. After incubation for 3 days at 27° C, the growth of the bacterium was observed, whereby the minimum inhibitory concentration (MIC, μg/ml) of each compound was determined. Evaluation test of curative effect on soft rot of Chinese cabbage caused by E. carotovora was carried out in a similar method to that of Example 1, except that samples were sprayed on a plant at a concentration of 500 ppm 16 hours after inoculation. The results obtained are shown in Table 3 below.
TABLE 3______________________________________Test for Antibacterial Activityto Erwinia caratovara Severity ofCompound MIC (μg/ml) Disease______________________________________(1) 1.56 0(2) >50 12(3) 0.39 0(4) 0.78 0(6) 3.12 0(7) 0.78 0(8) >50 8(9) 1.56 0(10) 0.049 0(11) >50 12(12) 1.56 0(13) 0.78 0Nalidixic 6.25 100acidControl -- 100(No spray)______________________________________
EXAMPLE 3
Plant Systemic Activity
Chinese cabbage (Nozaki #2) at the two-leaf stage grown in a flower pot of a diameter of 9 cm was withdrawn from the soil with care not to injure the roots and the roots of the Chinese cabbage were immersed in a solution of the test compound at a concentration of 10 ppm. After 2 days, a suspension of Erwinia carotovora was inoculated by scratching the leaves. The incidence of disease was assessed in the same manner as described in Example 1. Five plants were used for each treatment. The results obtained are shown in Table 4 below.
TABLE 4______________________________________Plant Systemic Activity Concentration Severity of Active of Ingredient DiseaseCompound (ppm) (%)______________________________________(1) 10 0(2) 10 0(4) 10 0(7) 10 0(8) 10 0(9) 10 0(10) 10 25(13) 10 0Streptomycin 10 31Sulfate*None -- 100______________________________________ *Commercially available comparison compound containing streptomycin as th active ingredient.
EXAMPLE 4
Test for Disease Prevention Effect on Angular Leaf Spot of Cucumber
Onto a cucumber (Cucumis sativus L. Sagami Hanjiro Fushinari) at the two-leaf stage grown in a flower pot having a diameter of 9 cm the test sample in a water-soluble powder form was diluted with water and sprayed at a rate of 15 ml per pot. Four hours after the application of the sample, a suspension of Pseudomonas lachrymans was inoculated by spraying on the plant. Thereafter, the plant was placed in a moist chamber (90-100% RH) for 3 days at 25° C and then placed in a green house for 3-4 days. Incidence of disease was assessed in the following manner. That is, the severity of disease was calculated according to the following relationship by measuring the ratio of the diseased area of the leaves, classifying it into grades of 0, 0.5, 1, . . . 4, and recording the number of leaves n 0 , n 1 , n 2 . . . n 5 corresponding to each index of the disease:
______________________________________Disease Index Ratio of Diseased Area______________________________________0 Healthy0.5 1-3% disease spots1 1-10% diseased spot areas2 11-25% diseased spot areas3 26-50% diseased spot areas4 >50% diseased spot areas ##STR22##______________________________________
Five plants were used for each treatment. The results obtained are shown in Table 5 below.
TABLE 5______________________________________Test for Disease Prevention Effecton Angular Leaf Spot of Cucumber Concentration Severity of Active of Ingredient DiseaseCompound (ppm) (%)______________________________________(1) 500 7.9(2) 500 25(4) 500 4.6(7) 500 12(8) 500 21(9) 500 19(13) 500 2.4Streptomycin 200 28Sulfate*Kocide** 830 46None -- 80______________________________________ *Commercially available comparison **Commercially available comparison compositioncontaining copper hydroxid as the active ingredient
EXAMPLE 5
Test for Disease Prevention Effect on Bacterial Wilt of Tomato
Tomatoes (breed: Sekai Ichi) at the 4-5 leaf stage grown in a flower pot of a diameter of 9 cm were inoculated with a soil drench of a suspension of Pseudomonas solanacearum at a rate of 20 ml per pot. After one day, the test compound in an emulsion form diluted with water was applied to the soil in the flower pot at a rate of 15 ml per pot. Then, after an additional 10 days, the incidence of disease condition was assessed. Four flower pots with two plants each were used for each treatment. The results obtained are shown in Table 6 below.
TABLE 6______________________________________Test for Disease Prevention Effecton Bacterial Wilt of Tomato Concentration Ratio of of Active Diseased Ingredient SeedlingCompound (ppm) (%)______________________________________(1) 500 10(2) 500 36(4) 500 6(7) 500 18(8) 500 24(9) 500 14(13) 500 4Streptomycin 200 86Sulfate*None -- 100None** -- 0______________________________________ *Commercially available comparison **Neither treated nor inoculated
EXAMPLE 6
Test for Disease Prevention Effect on Bacterial Leaf Blight of Rice Plant
Onto a rice plant (breed: Kinki #33) at the 5-leaf stage grown in a flower pot of a diameter of 9 cm, the test sample in an emulsion form diluted with water was sprayed at a rate of 10 ml per pot. After 4 hours, a suspension of Xanthomonas oryzae was inoculated by scratching the central portion of the second leaf. The inoculated plant was placed in a moist chamber (90-100% RH) for 1 day and cultivated in a green house. Seven days after the inoculation, the incidence of disease was assessed using the bacterial-exudation method. That is, the bacteria exuded from the leaf section cut at portions 1, 3 and 5 cm apart from the inoculated portion of the plant were observed using a microscope and then the severity of disease was calculated by the following relationship. ##EQU1## Five flower pots with 10 plants each were used for each treatment. The results obtained are shown in Table 7 below.
TABLE 7______________________________________Test for Disease Prevention Effect onBacterial Leaf Blight of Rice Plants Concentration Severity of Active of Ingredient DiseaseCompound (ppm) (%)______________________________________ (1) 500 0(2) 500 0(4) 500 0(7) 500 0(8) 500 0(9) 500 0(13) 500 0Chloromycetin* 200 1Phenazine** 200 45______________________________________ *Commercially available comparison composition containing chloroamphenico as the active ingredient. **Commercially available comparison composition containing phenazine-5-oxide as the active ingredient.
EXAMPLE 7
Test for Controlling Angular Leaf Spot of Cucumber by Seed Treatment
Seeds of cucumber (Cucumis sativus L. cv. Sagami Hanjiro Fushinari), which were inoculated by immersing them in a suspension of P. lachrymans at a concentration of 10 8 to 10 9 cells/ml for 30 minutes and followed by drying in air, were soaked in an aqueous solution of the test sample in an emulsion form for 30 minutes. Ten seeds were sowed in a flower pot containing sterilized soil. They were grown in a green house for 2 weeks. The number of infected cucumber plants were recorded. Fifty seeds were used for each treatment.
TABLE 8______________________________________Test for Controlling Angular Leaf Spotof Cucumber by Seed Treatment Concentration of Active Infected Ingredient PlantsCompound (ppm) (%)______________________________________(1) 500 0(2) 500 0(4) 500 0(7) 500 0(8) 500 0(12) 500 0(13) 500 0Sodium 2,000 7.5Hypochlorite*Streptomycin 200 26.5Sulfate*Water -- 77.3______________________________________ *Commercially available comparison compound.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A method for preventing and eradicating bacterial infectious plant disease which comprises applying to plants a composition containing, as an active ingredient, at least one 4(1H)-oxo-3-quinolinecarboxylic acid derivative represented by the general formula (I): ##STR1## wherein A represents --OCH 2 O--(at the 6 and 7 position) or ##STR2## (at the 5 and 6 position), wherein R 4 represents a hydrogen atom or a lower alkyl group; R 1 represents a hydrogen atom, a lower alkyl group, an amino group, an ammonium group or an alkali metal atom; R 2 represents a lower alkyl group, a halogenated lower alkyl group, a hydroxyalkyl group, an alkenyl group, or an alkoxyl group; and R 3 represents a hydrogen atom or a lower alkyl group. | 0 |
[0001] This is a divisional application of prior application Ser. No. 10/771,992 filed on Feb. 3, 2004.
[0002] This application claims a benefit of foreign priority based on Japanese Patent Applications No. 2003-026541, filed on Feb. 3, 2003, which is hereby incorporated by reference herein in its entirety as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0003] The present invention relates generally to a position sensor, and more particularly to a position sensor provided in an exposure apparatus that transfers a fine circuit pattern. The present invention is suitable, for example, for an exposure apparatus that uses ultraviolet light (“UV”) and extreme ultraviolet (“EUV”) light as an exposure light source and purges an exposure optical path.
[0004] A reduction projection exposure apparatus has been conventionally employed which uses a projection optical system to project a circuit pattern formed on a mask or a reticle onto a wafer, etc. to transfer the circuit pattern, in manufacturing such a fine semiconductor device as a semiconductor memory and a logic circuit in photolithography technology.
[0005] The minimum critical dimension (“CD”) to be transferred by the projection exposure apparatus or resolution is proportionate to a wavelength of light used for exposure, and inversely proportionate to the numerical aperture (“NA”) of the projection optical system. The shorter the wavelength is, the better the resolution is. Along with recent demands for finer semiconductor devices, a shorter wavelength of ultraviolet light has been promoted from an ultra-high pressure mercury lamp (i-line with a wavelength of approximately 365 nm) to KrF excimer laser (with a wavelength of approximately 248 nm) and ArF excimer laser (with a wavelength of approximately 193 nm). However, the lithography using the ultraviolet light has the limit to satisfy the rapidly promoting fine processing of a semiconductor device, and a reduction projection optical system using EUV light with a wavelength of 10 to 15 nm shorter than that of the ultraviolet (referred to as an “EUV exposure apparatus” hereinafter) has been developed to efficiently transfer a very fine circuit pattern.
[0006] The projection optical system is also required to improve throughput as the number of sheets exposed per unit of time. The improved throughput needs the shorter exposure time for each object to be exposed, and the increased exposure light intensity or light quantity or dose to be irradiated onto the object per unit of time. However, the light with a short wavelength is easily subject to absorptions in a material, and its light intensity remarkably decreases when the light transmits in the air or oxygen. Accordingly, the reduction projection optical system that uses light with a short wavelength as exposure light, such as F 2 laser and EUV light, closes the space for the optical path area through which the exposure light transmits, and purges the closed space with highly-purity gas (e.g., high-purity purge gas of helium and nitrogen) which is free of impurities, such as organic materials and oxygen, or vacuums up the optical path area through which the exposure light transmits so as to maintain the dose that reaches the wafer.
[0007] In particular, the EUV light remarkably decreases its light quantity after passing through a lens, and its light quantity becomes almost zero on a wafer when the EUV light is irradiated on the wafer through an optical system that uses a lens as used for visual light and UV light. The EUV exposure apparatus thus maintains light quantity on the wafer, by closing the space around the exposure light's optical path, by highly vacuuming the space, and by providing an optical system with only mirrors.
[0008] The conventional exposure apparatus forms a closed space with a diaphragm between a purged space that purges with purge gas or vacuums the space around a light source, an illumination optical system, a reticle, a projection optical system, and a stage, and an exposure light's optical path, and an external space outside the purged space. The exposure apparatus needs various sensing optical systems, such as an off-axis alignment (“OA”) optical system, a reticle alignment optical system, a focus detecting system, and a wafer position-sensing interferometer.
[0009] An OA optical system for detecting an alignment mark on the wafer and thereby a wafer position preferably locates an objective lens closer to the exposure area for a shorter interval or baseline amount between the exposure position and a measurement position of the OA optical system. This is because a wafer is moved to the exposure position by the baseline amount after the OA optical system finishes the alignment, and the alignment accuracy needs a stable and small baseline amount for reduced errors. This means that part of the OA optical system should be located in the purged space.
[0010] The reticle alignment optical system for detecting a reticle's position should arrange its part in the purged space since the reticle is located on the exposure light's optical path. In addition, the focus detection system and wafer position-sensing interferometer etc. should arrange their parts in the purged space because their objects to be detected are located in the purged space.
[0011] Therefore, these sensing optical systems arranged across the purged space and the external space maintain the closed space and its arrangement with a transmission window member as a diaphragm on the optical path that partitions the purged and external spaces.
[0012] The purged space has a pressure different from the external space due to a supply of purge gas or a vacuum atmosphere. A difference between two spaces is particularly very large when the purge space is vacuumed. Thus, a transmission window member as a diaphragm that partitions two spaces receives a large force, and often deforms and/or decenters. These deformation and decentering of the transmission window member on the optical path in the detection system have not been expected in the design, and result in magnification variance, color shift and aberration, such as distortion, deteriorating detection accuracy.
[0013] Referring now to FIG. 14 , a description will be given of a deformation of the transmission window member caused by a pressure difference. FIG. 14 is a schematic sectional view of the transmission window member deformed by the pressure difference. FIG. 14A shows a transmission window member 1000 at a diaphragm 1100 that partitions a purged space PE and an external space OE. Initially, the transmission window member 1000 does not receive any force or deform.
[0014] When the purged space PE is, for example, vacuumed, the pressure in the purged space PE decreases and the transmission window member 1000 receives a force P 1 toward the purged space PE, as shown in FIG. 14B , deforming like a meniscus lens. On the other hand, when high-purity purge gas is supplied to the purged area PE to increase its pressure, a force reverse to the force P 1 applies to the transmission window member 1000 .
[0015] Since the transmission window member 1000 perpendicularly receives the force P 1 , the generated birefringence directs perpendicular to the polarized direction of the incident light and seldom affects the optical performance. However, the diaphragm 1100 that holds the transmission window member 1000 generates a force P 2 in response to the force P 1 applied to the transmission window member 1000 , which force P 2 generates birefringence parallel to the polarized direction of the incident light and affects the polarization of the incident light.
[0016] When the purged space PE is vacuumed, extremely large force applies to the diaphragm 1100 and the transmission window member 1000 , and the diaphragm 1100 conceivably deforms and distorts, as shown in FIG. 14C . FIG. 14C schematically shows the deformed diaphragm 1100 by an angle θ in the purged space PE. Then, the transmission window member 1000 deforms with the diaphragm 1100 by an angle θ due to the deformation under a pressure difference. In other words, the decentering element includes not only the angle θ relative to the optical axis (which is referred to as an “inclined decenter” hereinafter), but also a shift Δd in a direction perpendicular to the optical axis associated with the inclined decenter (which is referred to as a “parallel decenter” hereinafter).
[0017] These deformations of the transmission window member possibly result from manufacture errors and changes with time. Regular adjustments need to correct changes with time, and otherwise the measurement accuracy would greatly deteriorate.
[0018] On the other hand, it is conceivable to arrange all the elements of the sensing optical system in the purged space instead of arranging part of them in the purged space and the rest in the external space. However, they include a heat source that thermally deforms a holding mechanism and other members, offsets a projection optical system, and deteriorates the measurement accuracy. Therefore, it is not possible to arrange all the elements of the sensing optical system in the purged space.
BRIEF SUMMARY OF THE INVENTION
[0019] Accordingly, it is an exemplary object of the present invention to provide a highly accurate position sensor that maintains the optical performance of its optical system that arranges on an optical path an element as a diaphragm between two spaces having different pressures, even when the element deforms.
[0020] A position sensor of one aspect according to the present invention for detecting position of an object disposed in a first space (i.e., the purged space PE) by receiving light from the object with a light receiving element disposed outside the first space (i.e., the external space OE), the position detecting apparatus includes an optical system for directing light from the object to the light receiving element, and a first optical element transmitting light from the object, disposed in the partitioning member for partitioning the first space and space outside the first space, wherein the first optical element is located on a position on or near a pupil plane (a Fourier transform plane with respect to optical system) or a plane conjugate to the pupil plane of the optical system.
[0021] The first optical element may be located on or near a pupil plane or a plane conjugate to the pupil plane which has a smallest effective diameter of light ray. The position near a pupil plane may be position between pupil plane and an at least one of closest optical element to the pupil plane on the image side and closest optical element to the pupil plane on the object side of the optical system.
[0022] The position near a plane conjugate to the pupil plane may be position between a plane conjugate to the pupil plane and an at least one of closest optical element to the plane conjugate to the pupil plane on the image side and closest optical element to the plane conjugate to the pupil plane on the object side of the optical system. The pressure of the first space and outside first space may be different. The first optical element may be the closest optical element to the light receiving element.
[0023] A position detecting apparatus of another aspect according to the present invention that uses light to detect a position of an object, the position detecting apparatus includes an optical element disposed on a partitioning member for partitioning two spaces having different pressures, and a correction member for correcting an optical change caused by a deformation of the optical element. The optical element may be a lens.
[0024] The correction member may be at least one of a parallel plate and a wedge optical member. A position detecting apparatus may further include a detector, located on an image surface of the object, for receiving the light from the object, wherein the correction member drives the detector, and corrects a positional offset on a plane perpendicular to an optical axis on an image surface of the object.
[0025] The correction member may be located at a position that generates sensitivity similar to the optical change, and the correction member corrects at least one of coma and spherical aberration. The optical change may include a magnification, and the correction member may include a processor for correcting the magnification through processing. A position detecting apparatus may further include a detector, located on an image surface of the object, for receiving the light from the object, wherein the correction member drives at least one of the detector and the object, and corrects a shift of a focus position.
[0026] A position detecting apparatus of another aspect according to the present invention located across a first space and a second space that has a different pressure from that of the first space, the position sensor using light to detect a position of an object that is located in the first space, the position sensor includes a detector, located in the second space (i.e., the external space OE), for receiving the light from the object, a polarizer that defines a polarization direction of the light, and an optical element that transmits the light, partitions the first and second spaces, and is closer to the detector than the polarizer. One of the first and second spaces may be maintained vacuum or in a reduced pressure.
[0027] An exposure apparatus of another aspect according to the present invention for exposing an object, the exposure apparatus comprising a position detecting apparatus used for an alignment or focusing of the object, the position detecting apparatus disposed in a first space by receiving light from the object with a light receiving element disposed outside the first space, the position detecting apparatus includes an optical system for directing light from the object to the light receiving element, and a first optical element transmitting light from the object, disposed in the partitioning member for partitioning the first space and space outside the first space, wherein the first optical element is located on a position on or near a pupil plane or a plane conjugate to the pupil plane of the optical system.
[0028] A device fabrication method of another aspect of the present invention includes the step of exposing an object using an exposure apparatus, and performing a development process for the object exposed. Claims for a device fabrication method for performing operations similar to that of the above exposure apparatus cover devices as intermediate and final products. Such devices include semiconductor chips like an LSI and VLSI, CCDs, LCDs, magnetic sensors, thin film magnetic heads, and the like.
[0029] Other objects and further features of the present invention will become readily apparent from the following description of the preferred embodiments with reference to accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a schematic view of an exposure apparatus of one aspect according to the present invention.
[0031] FIG. 2 is a schematic enlarged view of an off-axis alignment optical system shown in FIG. 1 .
[0032] FIG. 3 is a schematic view of an off-axis alignment optical system that has correction means.
[0033] FIG. 4 is a schematic view of a variation of an off-axis alignment optical system shown in FIG. 3 .
[0034] FIG. 5 is a schematic enlarged view of a wafer-surface position-sensing optical system shown in FIG. 1 .
[0035] FIG. 6 is a schematic view of an arrangement of optical elements that have curvature deformations in a basic sensing optical system.
[0036] FIG. 7 is a table showing results of deformed optical element at different positions in the sensing optical system shown in FIG. 6 .
[0037] FIGS. 8 ( a ), 8 ( b ), and 8 ( c ) are a schematic view showing changes at image positions on a plane that perpendicularly intersects the optical axis when a correcting optical element inclines on the optical path.
[0038] FIG. 9 is a schematic view of a color wedge for correcting color shifts.
[0039] FIGS. 10 ( a ), 10 ( b ), and 10 ( c ) are a schematic view showing part of the basic sensing optical system shown in FIG. 6 .
[0040] FIG. 11 is a schematic view of a variation of the basic sensing optical system shown in FIG. 6 .
[0041] FIG. 12 is a flowchart for explaining how to fabricate devices (such as semiconductor chips such as ICs and LCDs, CCDs, and the like).
[0042] FIG. 13 is a detail flowchart of a wafer process as Step 4 shown in FIG. 12 .
[0043] FIGS. 14 ( a ), 14 ( b ) and 14 ( c ) are schematic sectional view showing deformations of a transmission window member which result from pressure differences.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] With reference to accompanying drawings, a description will now be given of the present invention. The same element in each figure is designated by the same reference numeral, and a duplicate description thereof will be omitted.
[0045] In providing a position sensor that provides a highly accurate position sensor that maintains the optical performance of its optical system that arranges on an optical path an element as a diaphragm between two spaces having different pressures, even when the element deforms, the instant inventors have earnestly studied optical performance of an imaging optical system changed by a deforming optical element as a parallel plate, by providing a specific curvature to the optical element as a substitute for the deformed transmission window member 1000 shown in FIG. 14 , by arranging this optical element on an optical path in a sensing optical system, and by considering parallel and inclined decenters of the optical element that has a curvature deformation on its front and back surfaces.
[0046] FIG. 6 is a schematic view of an arrangement of optical elements that have a curvature deformation in a basic sensing optical system 10 . While this optical system is for illustrative purposes or not limited to both-side telecentric, it may be one-side, e.g., image-side or object-side telecentric.
[0047] The studied detection light covers wavelengths between 500 nm and 700 nm with a basic wavelength of 600 nm as a center, and different changes of the optical performance according to detection light's different wavelengths, which is referred to as a color shift hereinafter, are observed from results for both end wavelengths, i.e., 500 nm and 700 nm.
[0048] The sensing optical system 10 shown in FIG. 6 once images on-axis and off-axis rays emitted from an object surface through an objective lens 11 and a relay lens 12 , and forms an intermediate image 13 . 14 denotes a stop (or a pupil) arranged at a pupil position of the objective lens 11 and the relay lens 12 . The light that has once imaged on the intermediate image surface 13 is re-imaged on an image surface through an imaging lens front group 15 and an imaging lens back group 16 . 17 denotes a stop (or a pupil) arranged at a pupil position of the imaging lens front group 15 and back group 16 . It is assumed that the objective lens 11 and the relay lens 12 have a lateral magnification of 10 times, the imaging system (including the imaging lens front group 15 and back group 16 ) has a lateral magnification of 5 times, and the detection system 10 entirely has a lateral magnification β of 50 times. A diameter ratio between the pupils 14 and 17 is 6.2:1.0.
[0049] The instant embodiment arranges an optical element at seven points, provides the optical element with a curvature and decenter, and studies optical-performance changes of the imaging optical system. These seven points include a point “a” near the stop or pupil 14 (that has a Fourier-conversion relationship with the object surface) between the objective lens 11 and the relay lens 12 , a point “b” near the relay lens 12 between the relay lens 12 and the intermediate image surface 13 , a point “c” near the intermediate image surface 13 , points “d”, “e” and “f” between the stop or pupil 17 and the imaging lens back group 16 , and a point “g” between the imaging lens back group 16 and the image surface.
[0050] FIG. 7 is a table showing results of the optical element deformed at different points in the sensing optical system 10 shown in FIG. 6 . FIG. 7 shows change amounts of the optical performance when the optical element arranged at a predetermined position (i.e., one of the points “a” to “g”) is subject to a deformation or curvature, subject to a deformation or curvature and then parallel decenter, or subject to a deformation or curvature and then inclined decenter. Numerical values in the table in FIG. 7 use a value at the point “d” as a reference (1.00), and indicate a relative ratio to the reference, although the point “b” is also used as a reference when the point “d” has a value of 0.
[0051] First, a result of changing optical performance is reviewed when each surface of the optical element is subject to a deformation or curvature (see column A in the table in FIG. 7 ). In order to estimate a change amount of the optical performance when the optical element deforms, different curvatures are applied to respective surfaces R 1 A and R 2 A on the optical element, and individually generated aberrations are added to each other, as shown in FIG. 7 . The result indicated herein uses a basic wavelength of 600 nm.
[0052] Understandably, a distance Sk A between an image-surface side of the imaging lens back group 16 as the lens's last surface and the image surface greatly changes when the optical element is located at the points “a” and “b”. In particular, the point “b” indicates 255.4 times a value at the point “d”. This means that an imaging position greatly moves in the focus direction after before the purged space is vacuumed. Apparently, a position that increases the distance Sk A large is inappropriate to a location for the transmission window member.
[0053] The lateral magnification β A greatly changes at the point “b”. A change of the lateral magnification β A would result in an image production with an unexpected magnification, and cause a positional offset in an alignment measurement.
[0054] Next follows a study of influence on the optical performance when each surface of the optical element is subject to a deformation or curvature and inclined (see column B in the table in FIG. 7 ). In order to estimate a change amount of the optical performance when the optical element deforms and decenters at its surfaces R 1 B and R 2 B , different curvatures and inclined decenters are applied to respective surfaces R 1 A and R 2 A on the optical element, and generated aberrations are added to each other, as shown in FIG. 7 .
[0055] The most remarkable change in optical performance was a difference dy B COLOR SHIFT (“dy B CS”) in positional offset amount for each wavelength on a plane perpendicular to the optical axis and, in particular, the positional offset amount greatly changes a difference dy B CS at the point “a” among these points for the optical element. This means that when the alignment detection light has a wide-range wavelength, the wavelength causes a positional offset on the plane on which an imaging position is perpendicular to the optical axis.
[0056] Next follows a study of a positional offset amount dy B COLOR SHIFT PER SURFACE (“dy B CSS”) to a wavelength for each surface on the optical element. In order to compare the sensitivity for each surface on the optical element, an absolute value of a positional offset amount on each surface is individually calculated after the optical element is located at each position, and an average is used for comparison. Large values are seen at the point “a” as the pupil position or stop 14 for the objective lens 11 and the relay lens 12 , at the point “f” near the imaging lens back group 16 , and at the point “g” between the imaging lens back group 16 and the image surface. The optical element does not always deform so that both sides have the same curvature, a large shift amount is seen when a single surface has high sensitivity.
[0057] Regarding a change amount of influence on the sensing optical system 10 when a single surface of the optical element deforms, it has been found that points “d” and “e” are less influential than the point “f”. This is assumed that the point “d” is closer to the pupil 17 and has a smaller light effective diameter. The effective diameters at points “d”, “e” and “f” in the instant embodiment are as follows:
[0000] Point “d”:Point “e”:Point “f”=1:2.4:3.6
[0000] Therefore, it is concluded that the transmission window member is located at a position that has a small light effective diameter.
[0058] Next follows a study of influence on a change of the optical performance at a center wavelength when the optical element itself is inclined while receiving a deformation or curvature as an inclined decenter (at center wavelength) (see column C in the table in FIG. 7 ). The points “b” and “c” showed large changes in positional offset amount dy C on a plane perpendicular to the optical axis. The point “g” also showed a relatively large change.
[0059] The points “b” and “c” showed large changes in off-axis spherical aberration wah c . The points “d”, “e”, “f” and “g” did not show any change (i.e., almost zero) in off-axis coma wac c , and the points “a”, “b” and “c” showed changes. When these aberrations become large, the measurement reliability and stability deteriorate, since the original mark image is not transmits to the image pickup device, like a blurred image, and an image different from the original image is analyzed.
[0060] The points “d”, “e” and “f” show large values of color shift dy C CD , and other points show small values. Although the result indicates that the points “d”, “e” and “f” show large values of color shift dy C CD , the absolute values are insignificant and indifferent. Nevertheless, the color-shift correction, which will be described later, can sufficiently correct any practical problem.
[0061] Next follows a study of how similar light effective diameters affect the optical performance when the transmission window member changes its location. For example, the points “c” and “d” are compared with reference to the table in FIG. 7 . The point “c” is located near the intermediate image surface 13 , while the point “d” is located near the pupil 17 position in the imaging optical system. A light effective diameter ratio between them is: Point “c”:Point “d”=1:1.5. Therefore, the point “d” has a larger light effective diameter. However, it has been found from comparisons of numerical values in the table shown in FIG. 7 that the point “c” is more influential on the sensing optical system 10 . In other words, it is understood that influence on the optical performance changes according to locations of the transmission window member even when the light effective diameter is similar.
[0062] It is thus understood that when the transmission window member is provided at one of the points “a”, “b” and “c”, the performance of the sensing optical system 10 sensitively changes, that the transmission window member should be located at a position that has a small light effective diameter, and that the transmission window member is preferably close to the pupil.
[0063] The point “g” near the image surface exhibits small change amounts other than a color shift amount dy C , and thus is useful as a location for the transmission window member when the color shift is corrected. If there are plural image surfaces (including an intermediate image surface), it is apparent that a window member is arranged on an image surface that has a possibly higher magnification or, preferably, the highest magnification.
[0064] Accordingly, it can be concluded that the transmission window member is located preferably between the stop (or pupil) 17 shown in FIG. 6 and the imaging lens back group 16 , and more preferably at the point “d” from a comprehensive viewpoint.
[0065] Although the point “g” is useful for a location of the transmission window member, it generates a color shift, and a configuration to correct the color shift is vital.
[0066] An arrangement of the transmission window member to a position that does not affect the optical performance of the sensing optical system 10 has been described above, but as shown in the table in FIG. 7 , the non-influential level is not zero. Accordingly, a description will be given of a correction of influence on the sensing optical system when a force deforms the optical element, which provides an optical element having parallel planes as a substitute for the transmission window member.
[0067] Referring now to FIG. 6 , a description will be given of a correction of the distance Sk A between an image-surface side of the imaging lens back group 16 as the lens's last surface and the image surface. Since the distance Sk A changes as the imaging position shifts in a focus direction of the optical axis, a movement of an image surface of the image pickup device in the focus direction of the optical axis at the imaging position would be able to adjust a change of the distance Sk A .
[0068] In order to handle changes with time, the adjustment is preferably automatic. For example, a pressure sensor always measures a pressure difference between the purged and external spaces. When the measured pressure difference value exceeds a certain amount, a change amount of the transmission window member varies and an offset value can change. Accordingly, the instant embodiment provides the image pickup device with a drive system, detects the alignment mark while driving the image pickup device, and determines the best position for the image pickup device based on a detection signal. An alternative method detects an alignment mark while driving the object to be detected (such as a wafer) in a focus direction, and determines the best position.
[0069] In correcting the lateral magnification β A , a signal processing system recognizes and reflects in processing a change of the lateral magnification β A as an offset amount as a result of that the transmission window member is located.
[0070] In order to handle changes with time, this adjustment is preferably automatic. For example, an alignment mark with a known mark interval is measured. When the measured mark interval is signal-processed, the mark interval on an image can be recognized that takes the current magnification offset amount into account, since the mark interval is known. As a deformation or curvature amount of the transmission window member changes with time, the mark changes on the image and a true lateral magnification β A can be recognized. The magnification is corrected by using this true lateral magnification β A .
[0071] A correcting optical element located on the optical path can adjust a positional offset dy of the image on the image surface. FIG. 8 shows a schematic view of a changing image position on a plane that perpendicularly intersects the optical axis when the correcting optical element inclines on the optical path.
[0072] FIG. 8A schematically shows an imaging state of the light that has an angle of view, where an imaging position IP′ is different from the expected position due to a deformation of the transmission window member (not shown). As shown in FIG. 8B , the correcting optical element 20 is provided and inclined according to the positional offset amount. The light incident upon the optical element 20 is refracted and emitted by the optical element 20 at both surfaces 20 a and 20 b in accordance with Snell's law. Here, the incident light upon the optical element 20 is parallel to the exit light from the optical element 20 . The imaging position after the light transmits through the optical element 20 changes a position on a plane perpendicular to the optical axis and a focus according to an inclination degree of the optical element 20 (see FIG. 8C ). However, an enlargement system, such as a sensing optical system, has a small NA near the image pickup device and a focus change is negligible. Accordingly, an inclination of the correcting optical element 20 would be able to adjust a change of a positional offset dy of an image changes on the image surface.
[0073] Alternatively, an adjustment can use parallel decenter of the image pickup device. While it has been described that an adjustment of the distance Sk A needs to move the image pickup device in the focus direction, a movement on the plane perpendicular to the optical axis is sufficient to correct changes of the positional offset dy on an image on the image surface.
[0074] Since a change of the positional offset dy of an image on the image surface is directly connected, for example, to a change of a baseline amount in the OA optical system, when the positional offset is corrected, the baseline amount needs to be measured again.
[0075] Referring to FIG. 9 , a description will be given of a correction of a color shift that occurs when the transmission window member deforms. FIG. 9 is a schematic view of a color wedge 30 for correcting the color shift. The color wedge 30 arranges two wedge-shaped transmission elements 32 and 34 opposite to each other, where “d” is an interval between them.
[0076] Wide-range light (with wavelengths: λ 1 <λ 2 <λ 3 ) incident upon a side surface 32 a of the transmission element 32 from the left direction in FIG. 9 exits from a side surface 32 b having a gradient, at different exit angles (θ λ1 >θ λ2 >θ λ3 ) for each wavelength since the light has different refractive indexes to wavelengths. The light that has exited from the side surface 32 b of the transmission element 32 travels by a distance “d” between the transmission elements 32 and 34 , and enters a side surface 34 a of the transmission element 34 . Respective wavelengths have different refractive indexes even on the side surface 34 a of the transmission element 34 since a difference of refractive index. However, since these two transmission elements 32 and 34 have side surfaces 32 b and 34 a having the same gradient (θ), the beams emitted from the side surface 34 b of the transmission element 34 are parallel to the light incident upon the side surface 32 a of the transmission element 32 .
[0077] A color shift ΔX at the image point of light that has transmits through the color wedge 30 is proportional to the interval “d” between the transmission elements 32 and 34 . This configuration thus uses the color wedge 30 to correct a color shift caused by a deformation of the transmission window member.
[0078] In order to handle changes with time, an automatic color-shift correction is preferable. For example, a reference mark in each sensing system is measured with different wavelengths of the illumination light. A difference in measurement value for illumination light's wavelengths is obtained from the measured values, and the difference “d” between these two transmission elements 32 and 34 in the color wedge 30 is determined. The difference “d” between these two transmission elements 32 and 34 in the color wedge 30 is made freely adjustable by an automatic drive, and adjusted to the determined interval “d” that is the best interval for the color-shift correction amount.
[0079] A description will be given of a measurement and correction of an off-axis spherical aberration wah c and off-axis coma wac c .
[0080] A measurement method estimates an aberrational amount, for example, by drawing a contrast curve for the off-axis spherical aberration wah c . When the alignment mark is measured by changing focuses, a convex waveform can be drawn with a peak value of a contrast amount for a certain defocus position. Understandably, when this convex waveform has a small full width at half maximum and a low peak value, an amount of spherical aberration is small, whereas a large full width at half maximum means a large amount of spherical aberration.
[0081] When the OA optical system detects a step mark, for example, the off-axis coma wac c occurs as an asymmetry of a detection signal. When a correlation between this asymmetry and coma amount has been obtained in advance, the current optical system's coma can be estimated.
[0082] The off-axis spherical aberration wah c and the off-axis coma wac c can be corrected, when their values are ascertained. For example, an optical element that has a deformation amount (such as a curvature and a decenter) of the transmission window member with a reverse sign (such as an optical element that has a shape of the deformed transmission window member rotated by 180° around its center axis), is located at a position that has almost the same sensitivity as that at a position at which the transmission window member is located.
[0083] In view of the result that a single surface of the transmission window member has small sensitivity to the optical performance when the transmission window member is located at a position that has a small light effective diameter, the instant inventors have studied a case that shortens the focal distance while maintaining the magnification, thereby shortening the span of the sensing optical system and reducing the light effective diameter at the pupil. FIG. 10 is a schematic view showing part of the basic sensing optical system 10 shown in FIG. 6 (such as the imaging lens front group 15 and back group 16 and the stop 17 ).
[0084] Referring to FIG. 10A , the light, which has been once imaged on the intermediate image surface 13 through an objective lens and relay lens (not shown but similar to the objective lens 11 and the relay lens 12 in FIG. 10 ), images on the image surface by the imaging lens front group 15 and back group 16 as an imaging lens system. Here, 17 is a stop placed on the pupil surface of the imaging lens system that includes the imaging lens front group 15 and back group 16 .
[0085] The imaging lens system that includes the imaging lens front group 15 and back group 16 can reduce the light effective diameter at the stop 17 . More specifically, the shortened focal distance of the imaging lens front group 15 can reduce the light effective diameter at the stop 17 .
[0086] A ratio between an imaging lens front group 15 's focal distance f 15 and an imaging lens back group 16 's focal distance f 16 determines the imaging lens system's magnification. If the imaging lens front group 15 's focal distance f 15 is shortened, the imaging lens back group 16 's focal distance f 16 should be shortened to maintain the imaging lens system's magnification constant.
[0087] FIG. 10B shows a sensing optical system that takes the foregoing into account, and reduces the diameter of the pupil or stop 17 by Δd. FIG. 10B shortens the imaging lens front group 15 's focal distance f 15 and the imaging lens back group 16 's focal distance f 16 , and maintains the imaging lens system's magnification constant. As shown in FIG. 10C as an enlarged view around the stop or pupil 17 , the light effective diameter at the position of the pupil or stop 17 shown in FIG. 10B (see a middle broken line in FIG. 10C ) is smaller than that of the stop 17 shown in FIG. 10A (see a middle solid line in FIG. 10C ).
[0088] Since this arrangement can produce a position that can reduce the light effective diameter near the pupil, and lower a deterioration of the sensing optical system's performance when the transmission window member is located at this position.
[0089] While the shortened imaging lens front group 15 's focal distance f 15 and the shortened imaging lens system can reduce the light effective diameter near the pupil or stop 17 , as discussed, the shortened imaging lens system may not possibly configure lenses so as to maintain the span necessary for the detection optical system.
[0090] Accordingly, the sensing optical system can include three optical systems so that the second group's pupil has a reduced light effective diameter and arranges a transmission window member. Since the second optical system increases the magnification and shortens a span, the third optical system corrects the span to be a necessary length. Since the sensing optical system has three optical systems, the light effective diameter can be reduced further by making the second optical system's magnification larger than the necessary magnification. The third optical system can correct the unnecessarily increased magnification of the second optical system to the necessary magnification.
[0091] FIG. 11 shows a schematic view of a sensing optical system 10 A as a variation of the sensing optical system 10 shown in FIG. 6 . The sensing optical system 10 A contemplates an optical system that includes three groups and has 50 times as a whole. It has been found that the light effective diameter near a pupil or stop 17 of the second imaging lens system is preferably as small as possible at a position for the transmission window member to locate.
[0092] Since the imaging lens front group 15 determines the light effective diameter of the pupil or stop 17 of the second group, the sensing optical system 10 A adjusts the imaging lens front group 15 and attempts to reduce the light effective diameter of the pupil or stop 17 of the second group prior to other conditions, such as a magnification and a span, while these other conditions have fewer restrictions.
[0093] One solution to reduce the light effective diameter of the pupil or stop 17 of the second group is, for example, to an increased magnification of the imaging lens system, such as the imaging lens front group 15 and the imaging lens back group 16 , or a reduced focal distance of the imaging lens front group 15 . Thereby, the transmission window member is located near the pupil or stop 17 of the second group that has reduced the light effective diameter.
[0094] The third group re-images light on an image surface through the third group's imaging lens group 19 , which has formed an image on the intermediate image surface 18 through the second group's imaging lens system, such as the imaging lens front group 15 and the imaging lens back group 16 . The third group corrects the performance of the sensing optical system 10 A as required. If the first group's objective lens 11 and relay lens 12 have 10 times, and the second group's imaging lens front group 15 and back group 16 have a relatively high magnification, for example, 8 times for a reduced light effective diameter at a position for the transmission window member to locate, the sensing optical system 10 A has the magnification of 80 times up to the second group.
[0095] When the third group sets its magnification to be 0.625 times, the sensing optical system 10 A has an originally required magnification of 50 times. Since the second group is shortened for a reduced light effective diameter near the pupil or stop 17 in the second group, the third group is adjusted to have a necessary span and maintain locations for mirrors etc.
[0096] Since a color shift can occur when the second group has a larger magnification for a reduced pupil's diameter, the third group needs to correct the color shift.
[0097] A concrete description will now be given of an application example to a sensing optical system in an exposure apparatus. FIG. 1 is a schematic view of an exposure apparatus 100 of one aspect according to the present invention. The exposure apparatus 100 is a reduction exposure apparatus that exposes a circuit pattern formed on a reticle 112 onto a wafer 115 .
[0098] The exposure apparatus 100 accommodates a light source 110 , an illumination optical system 111 , a reticle 112 , a reticle stage 113 , a projection optical system 114 , a wafer 115 , a wafer stage 116 , various sensing optical systems, and an optical path of the exposure light and its vicinity in a purged space PE that is a closed space and purged with purge gas or vacuumed, and includes an external space OE other than the purged space PE, a diaphragm 120 that partitions these spaces, a transmission window member 130 provided at the diaphragm 120 for an optical system that is arranged across these purged space PE and external space OE, etc.
[0099] The exposure apparatus is referred to as a stepper, when illuminating light from the top of the reticle 112 and sequentially exposing the reticle pattern onto the wafer 115 through the projection optical system 114 at a fixed position. On the other hand, the exposure apparatus is referred to as a scanner or scanning exposure apparatus, when relatively moving the reticle 112 and the wafer 115 at a speed ratio corresponding to a reduction magnification of the projection optical system 114 .
[0100] When the exposure light uses the EUV light and the projection optical system 114 etc. include a lens, the light intensity remarkably reduces due to the optical absorption by the lens. Therefore, the illumination optical system 111 and the projection optical system 114 include reflection mirrors and the reticle 112 is formed as a reflection reticle.
[0101] On the other hand, the wafer 115 includes a type called a second wafer that has already formed a pattern. In forming a pattern on this wafer, the wafer position should be detected in advance. In addition, an alignment of the reticle 112 and a focus position on a rough surface of the wafer 115 should be required. FIG. 1 shows typical six types of sensing systems.
[0102] The OA optical system 140 is a sensing optical system that optically detects an alignment mark on the wafer 115 without using the projection optical system 114 . The OA optical system 140 is less subject to optical restrictions for wafer alignment without using the projection optical system 114 , and generally provides more precise detections than the detections that use the projection optical system 114 .
[0103] Referring now to FIG. 2 , a description will be given of the OA optical system 140 as a position sensor as one aspect according to the present invention. FIG. 2 is a schematic enlarged view of the OA optical system 140 shown in FIG. 1 . The OA optical system 140 has an illumination light source 141 that uses a halogen lamp, etc. to supply light with a wide-range wavelength or uses He—Ne laser to supply monochromatic light.
[0104] A wafer-stage position-sensing interferometer 170 , which will be described later, measures a lateral distance of the wafer stage 116 . Based on the measurement result, the wafer stage 116 drives and positions the alignment mark M on the wafer 115 within a range detectable by the OA optical system 140 . The illumination light emitted from the illumination light source 141 is reflected by the half mirror 143 via the illumination optical system's lens 142 , and then transmits through the transmission window member 130 provided at the diaphragm that partitions the purged space PE and the external space OE.
[0105] The illumination light that transmits through the transmission window member 130 is reflected by the mirror 146 via the imaging lens 144 and the relay lens 145 , and enters the objective lens 147 . The illumination light condensed by the objective lens 147 illuminates the alignment mark M on the wafer 115 that has been driven by the detection result by the wafer-stage position-sensing interferometer 170 and positioned by the observable range.
[0106] The reflected scatter light from the alignment mark M is reflected by the mirror 146 via the objective lens 147 , and enters the relay lens 145 . Then, the light transmits through the half mirror 143 via the imaging lens 144 and the transmission window member 130 , is condensed by the imaging lens 148 , and forms an image of the alignment mark M on the image pickup device 149 , such as a CCD.
[0107] An image signal of the image of the alignment mark M formed on the image pickup device 149 is sent to and processed by a processor 200 . The processor 200 detects a position of the alignment mark M on the wafer 115 and arrangement information formed in the wafer based on the information from the wafer-stage position-sensing interferometer 170 .
[0108] The transmission window member 130 is located at a position that has the smallest light effective diameter on the optical path in the OA optical system 140 . Therefore, the OA optical system 140 reduces a deterioration of its optical performance when a pressure difference between the purged space PE and the external space OE deforms the transmission window member 130 .
[0109] The OA optical system 140 locates the transmission window member 130 at a position that has the smallest light effective diameter between the imaging lenses 144 and 148 , and reduces the aberration and optical performance's sensitivity in comparison with the transmission window member 130 located at another position. This cannot completely eliminate aberration and a positional offset of an image, and they still remain.
[0110] Accordingly, the image pickup device 149 itself is made movable in a focus direction of the optical axis, as shown in FIG. 3 , so as to correct a variable distance Sk between an image-surface side of the imaging lens 148 as the lens's last surface and the image surface on the image pickup device 149 when the transmission window member 130 deforms. Here, FIG. 3 is a schematic view of the OA optical system 140 that has correction means.
[0111] The lateral magnification β is not subject to an optical correction and a structural correction, but rather adjusted by the magnification correction by the processor 200 after the image pickup device 149 forms an image. In FIG. 3 , the scatter-reflected light from the alignment mark M images on the image pickup device 149 via the OA optical system 140 . The image signal is sent to and processed by the processor 200 . Since this image processing can adjust the image's magnification β to a predetermined value, the lateral magnification β is corrected by an offset amount corresponding to its change caused by a deformation of the transmission window member 130 .
[0112] A positional offset dy of an image on the image surface is corrected by providing a correcting optical element 210 at an appropriate position between a sensing light's transmission and imaging on the image pickup device 149 , such as a CCD, and by inclining the optical element 210 . Since an inclination of the optical element 210 is proportional to a shift amount of the image, the positional offset dy is adjusted by inclining the optical element 210 while observing an image formed on the image pickup device 149 .
[0113] A color shift on the image surface (which means that an imaging position shifts according to wavelengths) is corrected by providing a color wedge 220 at an appropriate position between a sensing light's transmission and imaging on the image pickup device 149 , such as a CCD, and by inclining the optical element 210 . The color wedge 220 includes two opposite transmission elements 222 and 224 each having a wedge section, and used to correct the color shift since the shift amount for each wavelength changes in proportion to a changing interval between the transmission elements 222 and 224 .
[0114] These structures can correct aberration and a positional offset of an image, which cannot be eliminated only by arranging the transmission window member 130 at a position that has the smallest pupil's effective diameter, and enable highly precise measurements by the OA optical system.
[0115] The compressed transmission window member 130 can generate birefringence, which is difficult to be corrected by correction means as described with reference to FIG. 3 . However, it is anticipated that the birefringence affects polarization and is less influential on the optical performance of the OA optical system 140 if the transmission window member 130 is located subsequent to the polarizer that defines polarization. Accordingly, when the transmission window member 130 is located subsequent to or at the image side of the polarizer, for example, by using a polarization beam splitter, a deformation of the transmission window member 130 becomes less influential on the optical performance.
[0116] FIG. 4 is a schematic view of an OA optical system 140 A as a variation of the OA optical system 140 shown in FIG. 3 . The OA optical system 140 A is similar to the OA optical system 140 shown in FIG. 3 , but attempts to reduce influence of the birefringence caused by a deformation of the transmission window member 130 .
[0117] Referring to FIG. 4 , the light emitted from the light source 141 illuminates a polarization beam splitter 230 through an illumination optical system's lens 142 . The polarization beam splitter 230 has different transmittance and reflectance according to polarized directions of the incident light. The polarization beam splitter 230 used for the instant embodiment reflects s-polarized light and transmits p-polarized light among the illumination light.
[0118] The illumination light reflected by the polarization beam splitter 230 transmits through the relay lens 145 through the imaging lens 144 and then is reflected by the mirror 146 . The illumination light reflected by the mirror 146 transmits a λ/4 plate 240 , and irradiates an alignment mark M through the objective lens 147 . The λ/4 plate 240 converts the s-polarized light into circularly polarized light, which is, in turn, irradiated onto the alignment mark M on the wafer 115 .
[0119] The scatter-reflected light from the alignment mark M enters the polarization beam splitter 230 via the objective lens 147 , the λ/4 plate 240 , the mirror 146 , the relay lens 145 , and the imaging lens 144 . The beam splitter 230 transmits the p-polarized light and reflects the s-polarized light, as described above. When the scatter-reflected light from the alignment mark M transmits through the λ/4 plate 240 , the circularly polarized light is converted into the p-polarized light. Therefore, the scatter-reflected light from the alignment mark M transmits through the polarization beam splitter 230 , and images on the image pickup device 149 through the transmission window member 130 , the imaging lens 148 , the optical element 210 , and the color wedge 220 .
[0120] The OA optical system 140 A arranges the transmission window member 130 subsequent to the polarizer, reduces the influence of the birefringence caused by a deformation of the transmission window member 130 , and provides highly precise measurements.
[0121] The OA optical system 140 arranges an illumination light source 141 in the purged space PE, but the illumination light source 141 would cause a problem of thermal radiation. Therefore, the illumination light source 141 may be installed in the purged space PE if the problems of thermal radiation, etc. are solved, but otherwise it is preferable to arrange the illumination light source 141 in the external space OE and to use an irradiation through the transmission window member 130 .
[0122] The wafer-surface position-sensing optical system 150 measures, in an oblique incidence manner, a focus position of a rough surface (in an optical-axis direction of the projection optical system 140 ) of the wafer 115 as a substrate. The exposure apparatus 100 increases the numerical aperture of the projection optical system 114 to enhance the resolution, and thus the depth of focus becomes small. Therefore, the autofocus mechanism is needed to focus the surface of the wafer 115 on the image surface of the projection optical system based on a measurement result of a surface state of the wafer 115 by the focus position-sensing optical system that uses the oblique incidence manner, like the wafer-surface position-sensing optical system 150 .
[0123] FIG. 5 shows a schematic enlarged view of the wafer-surface position-sensing optical system 150 shown in FIG. 1 . Referring to FIG. 5 , the light emitted from the light source 151 illuminates the slit plate 152 . Multipoint measurements are needed to simultaneously measure a tilt amount and focus of the wafer 115 . Accordingly, the slit plate 152 has plural slits, such as 3×3=9 points.
[0124] The light that has transmitted through the slit plate 152 enters the transmission window member 130 a that partitions the purged space PE and the external space OP, through an optical element 210 that corrects a positional offset, a color wedge 220 that corrects a color shift, a projection system front group 153 that includes a relay lens 153 a and an imaging lens 153 b , and a relay lens 154 a . The light that has transmitted through the transmission window member 130 a is imaged on the wafer 115 through the imaging lens 154 b.
[0125] Those elements from the slit plate 152 through the wafer 115 have a similar configuration as the sensing optical system 10 shown in FIG. 6 . The transmission window member 130 a is located near a pupil point of the projection optical system back group 154 or near one of a surface that Fourier-converts the slit plate 152 and a surface conjugate with the surface that Fourier-converts the slit plate 152 , which one has the smallest light effective diameter. Thus, a deformation of transmission window member 130 a is less influential to the optical performance.
[0126] The optical element 210 and the color wedge 220 at the back of the slit plate 152 correct positional and color shifts of an image at an imaging position on the wafer 115 .
[0127] The light that has been regularly reflected on the wafer 115 enters the transmission window member 130 b that partitions the purged space PE and the external space OP, through the light receiving system front group 155 that includes the relay lens 155 a and imaging lens 155 b , and the relay lens 156 a . The light that has transmitted through the transmission window member 130 b is imaged on the image-pickup device 157 through the imaging lens 156 b , an optical element 210 for correcting a positional offset, and a color wedge 220 for correcting a color shift.
[0128] When the wafer 115 shifts from the projection optical system 114 in a defocus direction, the image pickup device 157 of the wafer-surface position-sensing optical system 150 generates a positional offset from a plane perpendicular to the optical axis of the wafer-surface position-sensing optical system 150 . When the wafer 115 tilts, a tilt amount around the Y-axis is calculated from a span amount at a known measured point.
[0129] Thereby, the defocus and tilt amounts of the wafer 115 are recognized, and the result is sent to the processor 200 . Then, the processor 200 sends optimal values of the defocus and tilt amounts to the wafer stage 116 to correct the focus position and tilt of the wafer 115 .
[0130] Similar to the projection optical system, those elements on the wafer 115 from the object surface of the light receiving system (or imaging surface viewed from the light projection system) arrange the transmission window member 130 b near the pupil position of the light receiving system back group 156 , and reduce the influence on the optical performance of the wafer-surface position-sensing optical system 150 caused by a deformation of the transmission window member 130 b.
[0131] The optical element 210 and the color wedge 220 serve to correct positional and color shifts on the image surface for the image pickup device 157 as described for the projection system. In particular, the correction of a shift amount needs to carefully and regularly confirm the shift amount and execute alignments.
[0132] This structure enables the wafer-surface position-sensing optical system 150 to reduce aberrations and positional offsets caused by deformations of the transmission window members 130 a and 130 b , and to measure a position of the wafer 115 with high precision.
[0133] The reticle alignment optical system 160 detects whether relative positions between the reticle 112 and the reticle stage 113 are appropriate. The reticle alignment optical system 160 aligns the reticle 112 by observing in the same field the alignment mark on the reticle 112 and the reticle reference mark on the reticle stage 113 , and by measuring their relative positions.
[0134] The wafer-stage position-sensing interferometer 170 irradiates a laser beam onto a surface at the side surface of the wafer stage 116 and a reference surface, measures interference with light from the reference surface, and precisely measures a position of the wafer stage 116 .
[0135] The reticle-surface position-sensing optical system 180 measures a surface shape of the reticle 112 in an oblique incidence manner. The improved resolution of the exposure apparatus 100 cannot neglect a deformation of the reticle, which is caused by a deformation of the reticle 112 by its own weight, a flatness of the reticle pattern surface, a flatness of a contact surface in absorbing and holding the reticle onto a reticle holder, etc. A deformation of the reticle 112 is different according to reticles, and thus it is necessary to measure the deformation after the reticle 112 is mounted. The reticle-surface position-sensing optical system 180 measures a surface shape of the reticle 112 , and corrects a position of the reticle pattern surface in a height direction, thereby compensating imaging performance.
[0136] The position-sensing optical system 190 uses exposure light etc., reticle 112 and the projection optical system 114 to measure relative positions between the reticle 112 and the wafer 115 in a through the lens auto alignment (“TTL-AA”) manner. In the position-sensing optical system 190 , the illumination light emitted from the light source 191 is reflected by the half mirror 192 and enters the transmission window member 130 through the lens 193 .
[0137] The illumination light that has transmitted through the transmission window member 130 is reflected on the mirror 194 and irradiates the alignment mark (not shown) on the reticle 112 . The image pickup device 195 images the scattered reflected light from the alignment mark via the mirror 194 , the transmission window member 130 , the lens 193 , and the half mirror 192 .
[0138] The detection light that has transmitted through the transmission area other than the alignment mark on the reticle 112 illuminates the alignment mark on the wafer 115 via the projection optical system 114 . The scattered reflected light from the alignment mark 115 transmits through the projection optical system 114 , and imaged by the image pickup device 195 through the transmission area other than the alignment mark on the reticle, the mirror 194 , the transmission window member 130 , lens 193 and the half mirror 192 .
[0139] Thus, the alignment mark on the reticle 112 and the alignment mark on the wafer 115 can be simultaneously observed to measure a relative positional relationship (in a direction perpendicular to the optical axis of the projection optical system 114 ) and a conjugate relationship (for focusing) between the reticle 112 and the wafer 115 .
[0140] The exposure apparatus 100 arranges the transmission window member 130 at a position having the smallest light effective diameter for the OA optical system 140 and the wafer-surface position-sensing optical system 150 . Of course, the present invention is applicable to such an optical system as includes a transmission window member for portioning two spaces that have different pressures, such as the reticle alignment optical system 160 , the wafer stage position-sensing interferometer 170 , the reticle-surface position-sensing optical system 180 , and the position-sensing optical system 190 .
[0141] A description will be given of the transmission window member 130 provided at the diaphragm 120 that partitions the purged space PE and the external space OE. A reduced deformation amount of the transmission window member 130 caused by a pressure difference between the purged space PE and the external space OE would be less influential to the optical performance.
[0142] For example, the instant embodiment assumes that the transmission window member 130 has a thickness of several millimeters, but the transmission window member 130 that has been made thicker would reduce the deformation amount and reduce influence on the optical performance. Alternatively, the transmission window member 130 may be made of a glass material that has physical properties that are less deformable under the pressure.
[0143] Thus, an increased thickness and a proper material selection for the transmission window member 130 would reduce a deformation of the transmission window member 130 . However, a deformed diaphragm 120 that partitions the purged space PE and the external space OE would result in inclined and parallel decenters. Accordingly, as discussed, an arrangement of the transmission window member 130 at a position that is less influential to the optical performance under the inclined and parallel decenters would reduce aberration and an image displacement.
[0144] In exposure, the light emitted from the light source 110 Koehler-illuminates the reticle 112 via the illumination optical system 111 . The light from the reticle 112 and reflects the reticle pattern is imaged onto the wafer 115 by the projection optical system 114 . The exposure apparatus uses various sensing optical systems that precisely detect a position of their objects for alignments, and provide higher quality devices than the conventional, such as semiconductor devices, LCD elements, image pickup devices (e.g., CCDs), and thin film magnetic heads, with excellent economical efficiency and throughput.
[0145] Referring now to FIGS. 12 and 13 , a description will be given of an embodiment of a device fabricating method using the exposure apparatus 100 . FIG. 12 is a flowchart for explaining a fabrication of devices (i.e., semiconductor chips such as IC and LSI, LCDs, CCDs, etc.). Here, a description will be given of a fabrication of a semiconductor chip as an example. Step 1 (circuit design) designs a semiconductor device circuit. Step 2 (mask fabrication) forms a mask having a designed circuit pattern. Step 3 (wafer preparation) manufactures a wafer using materials such as silicon. Step 4 (wafer process), which is referred to as a pretreatment, forms actual circuitry on the wafer through photolithography using the mask and wafer. Step 5 (assembly), which is also referred to as a posttreatment, forms into a semiconductor chip the wafer formed in Step 4 and includes an assembly step (e.g., dicing, bonding), a packaging step (chip sealing), and the like. Step 6 (inspection) performs various tests for the semiconductor device made in Step 5 , such as a validity test and a durability test. Through these steps, a semiconductor device is finished and shipped (Step 7 ).
[0146] FIG. 13 is a detailed flowchart of the wafer process in Step 4 . Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer's surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor disposition and the like. Step 14 (ion implantation) implants ion into the wafer. Step 15 (resist process) applies a photosensitive material onto the wafer. Step 16 (exposure) uses the exposure apparatus 100 to expose a circuit pattern on the mask onto the wafer. Step 17 (development) develops the exposed wafer. Step 18 (etching) etches parts other than a developed resist image. Step 19 (resist stripping) removes disused resist after etching. These steps are repeated, and multilayer circuit patterns are formed on the wafer. The device fabrication method of this embodiment may manufacture a higher quality device than the conventional method.
[0147] Further, the present invention is not limited to these preferred embodiments, and various variations and modifications may be made without departing from the scope of the present invention.
[0148] Thus, the present invention can provide a highly accurate position sensor that maintains the optical performance of its optical system that arranges on an optical path an element as a diaphragm between two spaces having different pressures, even when the element deforms. | A position detecting apparatus for detecting position of an object disposed in a first space by receiving light from the object with a light receiving element disposed outside said first space, said position detecting apparatus includes an optical system for directing light from the object to the light receiving element, and a first optical element transmitting light from the object, disposed in a partitioning member for partitioning said first space and space outside said first space, wherein said first optical element is located on a position on or near a pupil plane or a plane conjugate to the pupil plane of said optical system. | 6 |
The following is based upon and claims priority to U.S. Provisional Application Ser. No. 60/521,934, filed Jul. 22, 2004 and U.S. Provisional Application Ser. No. 60/522,023, filed Aug. 3, 2004.
BACKGROUND OF THE INVENTION
Field of Invention
The present invention relates to the field of measurement. More specifically, the invention relates to a device and method for taking downhole measurements as well as related systems, methods, and devices.
SUMMARY
One aspect of the present invention is a system and method to measure a pressure or other measurement at a source (e.g. a hydraulic power supply) and in or near a downhole tool and compare the measurements to verify that, for example, the supply is reaching the tool. Another aspect of the present is a system and method in which a gauge is positioned within a packer. Yet another aspect of the invention relates to a gauge that communicates with the setting chamber of a packer as well as related methods. Other aspects and features of the system and method are further discussed in the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The manner in which these objectives and other desirable characteristics can be obtained is explained in the following description and attached drawings in which:
FIG. 1 illustrates an embodiment of the present invention including a downhole tool, a supply, and alternate pressure measurements.
FIG. 2 shows an alternative embodiment of the present invention.
FIG. 3 illustrates an embodiment of the present invention deployed in a well.
FIG. 4 illustrates a subsection of FIG. 3 .
FIG. 5 is a schematic of the present invention and the embodiment of FIG. 3 .
FIG. 6 illustrates another embodiment of the present invention in which a gauge is incorporated into a packer.
FIGS. 7 and 8 illustrate yet another embodiment of the present invention in which a gauge is provided above a packer and communicates with an interior of the packer.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
DETAILED DESCRIPTION OF THE INVENTION
In the following description, numerous details are set forth to provide an understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.
The present invention relates to various apparatuses, systems and methods for measuring well functions. One aspect of the present invention relates to a measurement method comprising measuring a characteristic of a supply, measuring the characteristic in or near a downhole tool and spaced from the supply measurement, and comparing the measurements (e.g., using a surface or downhole controller, computer, or circuitry). Another aspect of the present invention relates to a measurement system, comprising a first sensor adapted to measure a characteristic of a supply, a second sensor adapted to measure the characteristic in or near a downhole tool, the second sensor measuring the characteristic at a point that is spaced from the supply measurement. Other aspects of the present invention, which are further explained below, relate to verifying downhole functions using the measurements, improving feedback, providing instrumentation to downhole equipment without incorporating the gauges within the equipment itself and other methods, systems, and apparatuses. Further aspects of the present invention relate to placement of gauges in or near packers as well as related systems and methods.
As an example, FIG. 1 illustrates a well tool 10 attached to a conduit 12 . The tool has a hydraulic chamber 14 , such as a setting chamber, therein. The hydraulic chamber 14 may be, for example, an area within the tool 10 into which hydraulic fluid is supplied to actuate the tool 10 . A remote source 16 supplies hydraulic fluid to the well tool 10 (i.e., the hydraulic chamber 14 ) via a hydraulic control line 18 . The source 16 may be located at the surface or downhole. A first sensor 20 measures a characteristic at the source 16 . For example, the sensor 20 may measure the pressure of the hydraulic fluid at the source 16 that is supplied to the control line 18 . A second sensor 22 measures the characteristic in the control line 18 at a position near the tool 10 and spaced from the first sensor measurement. If applied to the example mentioned above, the second sensor may measure the pressure in the control line 18 proximal the well tool 10 . FIG. 1 also shows an alternative design in which the alternative second sensor 24 measures the characteristic in the tool 10 (e.g., in the hydraulic chamber 14 ). The alternative second sensor 24 may be external to the tool 10 in which case the sensor 24 is hydraulically and functionally plumbed to measure the pressure in the tool 10 . Alternatively, the sensor 10 is positioned within the tool 10 . The sensors 22 and 24 are described as alternatives and only one may be used, although alternative arrangements may use both sensors 22 and 24 .
In use, the measurements from the first sensor 20 and the second sensor 22 and/or alternative second sensor 24 are compared. The comparison may reveal whether the supplied fluid is actually reaching the tool. For example, if the control line 18 is blocked the measurements between the first sensor 20 and the second sensor 22 (or alternative second sensor 24 ) will be different. If these values are substantially the same, the operator can determine that the source is actually reaching the tool.
FIG. 2 illustrates another aspect of the present invention in which the two sensors 20 and 22 of FIG. 1 are replaced with a differential sensor 26 (e.g., a differential pressure gauge). The measurement of the differential sensor 26 can likewise indicate potential problems in and provide confirmation of whether the supply is reaching the tool 10 . The differential sensor 26 is shown measuring the characteristic in the control line 18 near the tool 10 . However, as in the embodiment of FIG. 1 , the sensor could alternatively measure the characteristic within the tool 10 .
FIG. 3 illustrates one potential application of the present invention and a system and method of the present invention applied in a multizone well 30 . A lower completion 32 for producing a lower zone of the well 30 has a sand screen 34 , packer 36 , and other conventional completion equipment. An isolation system 40 above the lower completion 32 comprises a packer 42 and an isolation valve 44 . The isolation valve 44 selectively isolates the lower completion 32 when closed. An upper completion 50 (see also FIGS. 4 and 5 ) for producing an upper zone of the well 30 comprises, from top to bottom, a hydraulically set packer 52 (e.g., a production packer or gravel pack packer), a gauge mandrel 54 , an annular control valve 56 , an in-line control valve 58 and a lower seal assembly 60 . The lower seal assembly 60 stabs into the isolation assembly 40 to hydraulically couple the upper completion 50 to the isolation assembly 40 . Thereby, the in-line control valve 58 is in fluid communication with the lower completion 32 and may be used to control production from the lower completion 32 . The annular control valve 56 of the upper completion 50 may be used to control production from the upper formation. The gauge mandrel 54 houses numerous pressure gauges 62 .
After the upper completion 50 is placed in the well 30 the annular valve 56 and the in-line valve 58 are both closed and pressure is applied inside the production tubing 64 to test the tubing 64 . The packer 52 is then set.
In order to set the packer 52 of the upper completion 50 , the annular valve 56 is closed and the in-line valve 58 is opened. The isolation valve 44 is closed and the pressure in the tubing 64 is increased to a pressure sufficient to set the packer 52 . A packer setting line 66 extends from the packer 52 and communicates with the tubing 64 at a position below the in-line valve 58 . In this example, the pressure in the tubing 64 acts as the source of pressurized hydraulic fluid used to set the packer. This porting of the packer 52 is necessary to prevent setting of the packer 52 during the previously mentioned pressure test of the tubing 64 .
One of the pressure gauges 62 a communicates with the interior of the tubing 64 , the source of the pressurized setting fluid, via a gauge ‘snorkel’ line 68 . The snorkel line 68 communicates with the tubing 64 at a position below the in-line valve 58 and, thereby, measures the pressure of the source of pressurized hydraulic fluid used to set the packer. This pressure gauge 62 a provides important continuing data about the produced fluid and well operation.
It is often desirable to have a second redundant pressure gauge 62 b or sensor that measures the same well characteristic to, for example, verify the measurement of the first gauge, provide the ability to average the measurements, and allow for continued measurement in the event of the failure of one of the gauges. Typically, the primary gauge 62 a and the back-up gauge 62 b are ported via independent snorkel lines 68 to the substantially same portions of the well. However, in the present invention, the ‘redundant’ pressure gauge 62 b is plumbed to and fluidically communicates with the packer setting line 66 via connecting line 70 . Therefore, the redundant pressure gauge 62 b measures the pressure in the packer setting line 66 near the packer 52 at a location that is spaced from the location of the measurement of the first pressure gauge 62 a . Both pressure gauges 62 a and 62 b remain in fluid communication with the production tubing 64 at a point below the in-line valve 58 and provide the important continuing data about the produced fluid and well operation at this portion of the well. However, by fluidically connecting the back-up gauge 62 b , the operator can determine whether a blockage has occurred in packer setting line 66 between the inlet 72 and the connection point 74 to the connecting line 70 . Positioning the connection point 74 near the packer 52 helps to verify that the pressurized fluid is actually reaching the packer 52 . In addition, using the connection line 70 attached to the packer setting line 66 can reduce the amount of hydraulic line used in the completion. Additionally, due to system used in the present invention, the pressure gauge 62 b provides a dual function of measuring the pressure in the well and helping to verify that the packer 52 is set. The added feature is provided at a minimal incremental cost. In some cases, for example when operating in a high debris environment, the packer setting line 66 may become plugged. If the operator quantifiably knows that pressure either has or has not reached the packer setting chamber, successful mitigation measures may be more easily deployed.
Note that as mentioned above in connection with FIG. 1 , the connection point 74 may be moved to within the packer setting chambers to validate the actual pressure delivered to the packer 52 . Additionally, as discussed above in connection with FIG. 2 , the two pressure gauges may be replaced with a differential pressure gauge to provide the verification.
FIG. 6 illustrates an embodiment of the present invention in which a gauge 80 is positioned within a packer 82 potentially eliminating the need for a separate gauge mandrel. Note that the previous description and FIGS. 3-5 show a separate gauge mandrel 54 , located below the packer 52 , which houses the gauges 62 . The present embodiment may reduce the overall completion cost for some completions by eliminating the gauge mandrel 54 . The gauge 80 is mounted within the setting chamber 84 of the packer 82 in the embodiment shown in the figure, although the gauge 80 , may also be mounted within other portions of the packer 82 .
In FIG. 6 , the packer 82 has a mandrel 86 on which are slips 88 , elements 90 , and setting pistons 92 . Pressurized fluid applied to the setting chamber 84 hydraulically actuates the pistons 92 setting the packer 82 . In alternate designs, the pressurized fluid may be applied to the packer 82 by either a hydraulic control line 94 , which extends below the packer 82 as discussed previously or which extend to the surface (not shown), or via ports in the packer 82 that communicate with the tubing (the discussion of FIG. 7 will describe such a packer).
Typically, the space available in a packer 82 outside the mandrel 86 (e.g., in the setting chamber 84 ) is insufficient to house a gauge 80 such as a pressure gauge. However, with the advent of MEMS (“Micro-Electro-Mechanical Systems”) and nanotechnology it is possible and will increasingly become possible to make very small gauges. These gauges 82 may be placed within existing packers or the packers may be only slightly modified to accommodate the small gauges. In addition, other customized gauges may be employed.
The embodiment illustrated in FIG. 6 shows a packer that has two gauges 80 in the setting chamber 84 . Control line provides power and telemetry for the gauges 80 . One of the gauges 80 a communicates with the central passageway 98 of the mandrel 86 via port 100 and, thereby, measures the tubing pressure. The second gauge 80 b communicates with an exterior of the packer 82 and, thereby, measures the annulus pressure. Additional gauges 80 may be supplied and the gauges may be positioned and designed to measure the pressure at different places within the well. For example, control lines may run from the packer to various points in the well to supply the needed communication. Also, gauges and sensors other than pressure gauges may be used to measure other well parameters, such as temperature, flow, and the like. The gauge 80 could additionally be designed to measure the pressure within the setting chamber 84 . As discussed previously, measuring the pressure in the setting chamber 84 provides a confirmation that the pressure in the setting chamber 84 reached the required setting pressure for setting the packer 82 . In addition, the pressure gauge 80 positioned in the setting chamber 84 and adapted to measure the pressure in the setting chamber 84 may also measure and provide continuing data about the pressure via the pressure setting ports or control lines (e.g., snorkel lines). Thus, a pressure gauge 80 so mounted provides the dual purpose of confirming packer setting and providing continuing pressure data.
By placing the gauges 80 in the packer 82 , the gauges 80 are very well protected while eliminating the need for a separate mandrel. Eliminating the mandrel 54 also may eliminate the need for timed threads or other special alignment between the packer 80 and a mandrel 54 . In addition, the total length of the completion may be reduced, the cost of equipment and the cost of completion assembly may be reduced, and the electrical connections and gauges 80 can be tested at the “shop” rather than at the well site, or downhole. The present invention provides other advantages as well.
FIGS. 7 and 8 illustrate yet another embodiment of the present invention in which a gauge 80 is provided above a packer 82 and communicates with an interior of the packer 80 . The embodiment of FIGS. 7 and 8 show a pressure gauge 80 that communicates with the interior setting chamber 84 of the packer 82 via a passageway 102 , which in turn communicates with the interior central passageway 98 of the packer 82 via radial setting ports 104 . In this way, the pressure gauge 82 can measure the pressure in the setting chamber 84 to confirm the setting pressure as well as the pressure in the central passageway 98 to measure the tubing pressure and provide continuing pressure information about the production and the well.
The present invention may be used with any type of packer. FIG. 7 shows the present invention implemented in one type of hydraulic packer 82 . For a detailed description of a similar packer, please refer to U.S. Patent Application Publication No. U.S. 2004/0026092 A1. In general, the packer 82 shown has a mandrel 86 on which are slips 88 , elements 90 , and setting pistons 92 . Setting ports 104 extend radially through the mandrel 86 providing fluid communication between an interior central passageway 98 of the mandrel 86 to a packer setting chamber 84 in the packer 82 . The setting ports 104 communicate the tubing pressure through the mandrel 86 into the setting chamber 84 of the packer 82 .
The packer 82 shown is hydraulically actuated by fluid pressure that is applied through a central passageway 98 of the mandrel 86 . The pressure of the fluid in the central passageway 98 is increased to actuate the pistons 92 to set the packer 82 .
The figures show the gauge 80 connected to the top of the packer 82 . This type of connection eliminates the need for an additional gauge mandrel 54 . In alternative designs, the gauge 80 may be placed further above the packer 82 with a conduit (e.g., snorkel line) connecting the gauge 80 to the packer 82 .
As mentioned above, because the gauge 80 measures the pressure of the setting chamber 84 , it is possible to follow the setting sequences of the packer 82 . The sensor also provides the dual function of also measuring the tubing pressure in the packer 82 shown. Note that if the packer 82 is set by annulus pressure or control line pressure, a gauge communicating with the setting chamber 84 measures the pressure from that pressure source 16 . In addition, the invention of FIGS. 7 and 8 , as well as that of FIG. 6 , may be implemented in other types of packers, such as mechanically set packers. The packer 82 may be ported in a variety of ways and additional passageways or ports may be provided to allow measurement at other points in the well (e.g., ports to the annulus, snorkel lines to other locations or equipment in the well, passageways in a mechanically-set packer, etc).
Furthermore, the inventions of FIGS. 6-8 may be used in the confirmation system previously discussed. Specifically, in both of the inventions of FIGS. 6 and 7 - 8 , a pressure gauge 80 may be used to measure the pressure in the setting chamber 84 . The pressure data from the gauge 80 may be compared to a measurement at the supply to confirm that the source 16 is reaching the setting chamber. In addition, additional gauges 80 in the packer 82 (e.g., in the embodiment of FIG. 6 ) may be ported to communicate with the source 16 to provide the desired measurements while potentially eliminating the need for a gauge mandrel 54 . These dual gauges 80 may also provide the desired redundancy discussed above depending upon the porting of the gauges.
Note that in the above embodiments, the gauge is ported or positioned to measure the actual or direct characteristic as opposed to an indirect characteristic. For example, the gauge 80 in FIG. 7 is directly ported to the setting chamber 84 of the packer 82 and thus provides a direct measurement. This is opposed to an indirect measurement in which a tubing pressure measurement remotely located or not interior to the packer 82 is made to show setting chamber pressure.
The above discussion has focused primarily on the use of pressure gauges in packers, although some other measurements are mentioned. It should be noted, however, that the present invention may be incorporate other types of gauges and sensors (e.g., in the packer of as shown in FIG. 6 or to compare measurements from two sensors, etc.). For example, the present invention may use temperature sensors, flow rate measurement devices, oil/water/gas ratio measurement devices, scale detectors, equipment sensors (e.g., vibration sensors), sand detection sensors, water detection sensors, viscosity sensors, density sensors, bubble point sensors, pH meters, multiphase flow meters, acoustic detectors, solid detectors, composition sensors, resistivity array devices and sensors, acoustic devices and sensors, other telemetry devices, near infrared sensors, gamma ray detectors, H2S detectors, CO2 detectors, downhole memory units, downhole controllers, locators, strain gauges, pressure transducers, and the like.
Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. For example, much of the description contained here deals with pressure measurement and pressure sensors, in other applications of the present invention the sensors may be designed to measure temperature, flow, sand detection, water detection, or other properties or characteristics. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. § 112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function. | One aspect of the present invention is a system and method to measure a pressure or other measurement at a source (e.g. a hydraulic power supply) and in or near a downhole tool and compare the measurements to verify that, for example, the supply is reaching the tool. Another aspect of the present invention is a system and method in which a gauge is positioned within a packer. Yet another aspect of the invention relates to a gauge that communicates with the setting chamber of a packer as well as related methods. Other aspects and features of the system and method are also described. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 4 |
FIELD OF THE INVENTION
The present invention relates to a driveshaft for a motor vehicle and more particularly to a telescoping driveshaft having an energy absorption feature.
DESCRIPTION OF THE PRIOR ART
In a rear wheel drive motor vehicle, a driveshaft transmits torque from the transmission through a differential to the rear wheels of the motor vehicle. During a frontal crash, energy is imparted upon the vehicle and deforms the components in a longitudinal manner. Typically, the engine and transmission are driven rearward in a frontal crash, causing the driveshaft to buckle during such an impact. This is likely to cause extensive damage to adjacent underbody components.
U.S. Pat. No. 5,580,314 describes an energy-absorbing intermediate shaft for a steering column. With a column as described in the '314 patent, a portion of the intermediate shaft is reduced to more predictably buckle during a crash and thereby absorb energy during a crash. However, the radial excursion of this design while the shaft buckles may cause damage to adjacent components, and therefore may require a large amount of clearance around the shaft to function properly.
It would be desirable to provide a telescoping shaft with better energy absorption characteristics and one which provides improved longitudinal deformation during a crash.
SUMMARY OF THE INVENTION
It is thus an object of the present invention to provide a driveshaft which axially collapses during a crash and absorbs energy while remaining substantially axially aligned.
A driveshaft assembly according to the present invention includes a male shaft having an outer surface and a female shaft slidably engaged with the male shaft. The shafts absorb energy during axial deformation of the driveshaft while maintaining alignment of the male and female shafts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial sectional side view of a driveshaft according to the present invention.
FIG. 2 is the driveshaft of FIG. 1 after compression.
FIG. 3 is a rear sectional view through the driveshaft of FIG. 1 .
FIGS. 4 and 5 are partial sectional views of the female and male shafts of FIG. 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1, a driveshaft assembly 10 according to the present invention is provided. The driveshaft assembly 10 is illustrated in a position prior to a crash, that is, the driveshaft assembly 10 has not been collapsed. FIG. 2 illustrates the driveshaft assembly 10 after collapse.
The driveshaft assembly 10 rotates about an axis to transmit torque in a known manner. A male member 12 is rotatably drivably engaged with a female member 14 through a splined connection 15 . Accordingly, the female member 14 includes an internally splined portion 16 slidably engaged with an externally splined portion 17 of the male member 12 . The internally splined portion 16 extends for a first length from the rear end of the female member 14 . Likewise, the splined portion 17 of the male member 12 extends for a length at the front end thereof. A transition 20 , 26 is formed between the splined 16 , 17 and unsplined portions 22 , 21 of the female and male members 14 , 12 .
While the vehicle is driven, the male member 12 moves axially with respect to the female member 14 through the splined connection 15 . During a crash with a longitudinal component, the female member 14 is urged axially rearwardly over the male member 12 . While the female member 14 thus moves rearwardly, and the internally splined portion 16 is forced beyond the externally splined portion 17 , the internally splined portion 16 engages the transition 26 and the unsplined portion 21 of the male member 12 .
As illustrated in FIGS. 3-5, the splined portion 16 of the female member 14 comprises circumferentially spaced outwardly and inwardly projecting splines 31 , 32 formed as a circumferentially convoluted wall in the female member 14 . The front portion of the male member 12 likewise includes a splined portion 17 with mating outwardly and inwardly projecting splines 33 , 35 , formed as a circumferentially convoluted wall in the male member 12 .
In a preferred embodiment, each of the male and female members 12 , 14 are formed from cylindrical tubes, the male tube fitting inside of the female tube. The splined portions 16 , 17 are preferably cold formed in each of the tubes using a Grob process, which is well known to one skilled in the art. The Grob process cold thus forms the convoluted walls. The outwardly projecting splines 31 and 33 form an outer diameter 37 , 30 , respectively, which is approximately equal to the respective outside diameter of the tubes before the internally projecting splines 32 and 35 are formed in the members 14 , 12 . The number of splines 31 , 32 , 33 , 35 and depth thereof is application specific to ensure the driveshaft assembly 10 is capable of transmitting the torque for the particular application. In an exemplary preferred embodiment, the depth of the splines is approximately 0.2 inch and 26 externally projecting splines 31 , 33 are provided in each member 14 , 12 . The depth is defined as the distance from the top of a spline (indicated, for example, at the minor diameter of the male tube 12 at 34 ) to the outside, or major diameter, (indicated at 30 for the male tube 12 ) of an outwardly projecting spline 33 .
The female member 14 is preferably swaged forward of the unsplined portion 22 . The forward end of the female member 14 is thus reduced to a size which fits a standard weld yoke 24 for attachment to a universal joint as is well known to one skilled in the art. The rear end of the male member 12 is preferably likewise swaged to reduce the diameter thereof to fit an identical weld yoke 25 , as is known to one skilled in the art.
The splined portion 16 of the female member 14 has an inside, or minor, diameter 36 at the base of the internal splines 32 . The inside diameter 36 is smaller than the outside diameter of the transition 26 and unsplined portion 21 of the male member 12 . As the female member 14 is urged rearwardly, the interference therebetween causes the female member 14 to plastically deform and expand radially outwardly as illustrated in FIG. 2 . This expansion requires a large amount of energy due to the cold working of the female member 14 and thus absorbs a portion of the crash energy. Because the driveshaft assembly 10 is thereby permitted to collapse axially and does not buckle significantly, the vehicle may be in a condition to permit towing or driving of a damaged vehicle which would have otherwise required a trailer to transport the vehicle to a repair facility. More significantly, because the driveshaft assembly 10 does not buckle, adjacent components remain undamaged after a crash and therefore the damage to the vehicle is reduced.
The female member 14 includes an unsplined portion 22 forward of the splined portion 16 . The unsplined portion 22 preferably has an inside diameter larger than the outside diameter 30 of the splines of the male member 12 . Thus, during axial compression of the driveline assembly 10 as described above, the male member 12 moves freely within the unsplined portion 22 , as long as the male member 12 is not forced beyond the unsplined portion 22 . Preferably the female member 14 in front of the splined portion 16 has an axial length that is adequate to prevent the male member 12 from contacting the weld yoke 24 of the female member 14 during most crashes.
In an alternative embodiment, the unsplined portion 22 of the female member 14 has a diameter slightly less than the outside diameter 30 of the outwardly projecting male splines 33 , thus causing a second interference during a crash, and therefore causing radial expansion of the female member 14 at the unsplined portion 22 , or radial compression of the male splined portion 17 . Such expansion or compression occurs in a manner similar to that described above, to absorb additional crash energy. In such an alternative embodiment, this interference may enable a reduction of the amount of interference between the splined and unsplined portions of male and female members 12 and 14 . In this embodiment, the outwardly projecting splines 31 of the female member 14 have a smaller inside diameter than the outside, or major diameter 30 , of the external splines 33 of the male member 12 . Alternatively, the inwardly projecting splines 32 of the female member 14 have a greater depth (smaller inside diameter 36 ) than the minor diameter 34 of the splines 35 of the male member 12 .
In a further alternative embodiment, during the axial compression of the driveshaft assembly 10 , the male member 12 is also radially compressed when the splined portion 17 engages the transition 20 and unsplined portion 22 of the female member 14 , likewise absorbing some of the crash energy as described above. The expansion of the female member 14 and compression of the male member 12 occurs due to interferences as described in the preceding paragraphs, but the members 12 , 14 are modified to enable such compression of the male member 12 . One skilled in the art appreciates that in such an alternative embodiment, the modifications may include providing a thin wall section in the male member 12 or removing material from the male member 12 in the forward portion thereof, such as by providing axial slots, to facilitate compression thereof.
In a preferred embodiment, a boot seal 19 is provided to cover the splined connection 15 between the male and female members 12 , 14 , in part to keep contaminants out of the splined connection 15 . The boot seal 19 is clamped at each end thereof to the outside diameters of the members 12 , 14 in a known manner. In a preferred embodiment, the boot seal 19 includes a splined inside diameter 23 corresponding with the splined portion of the female member 14 and mates with the splines thereof. The boot 19 engages a smooth cylindrical surface of the male member 12 in a conventional manner. Although not illustrated, one skilled in the art appreciates the boot seal 19 may likewise engage splines on a male member 12 or a smooth surface of a female member 14 . During a crash, the members 12 , 14 are axially compressed and the boot seal is forced to slide along the outer surface of the male member 12 , thereby absorbing additional energy.
One skilled in the art appreciates that the diameters of the male and female member 12 and 14 may vary depending on the vehicle application and materials used. However, in common applications, the outside diameter of a male shaft may range between 2.5 to 4.0 inches where the shafts are preferably formed from a low carbon alloy steel, such as 1015 or 1026 steel. In such a preferred embodiment, the shafts have a wall thickness of approximately 0.065 inches. A preferred clearance between the male and female splines is approximately 0.03 inches on the diameter to facilitate axial movement therebetween. In a preferred embodiment, the interference of the unsplined portion 21 of the male member into the inwardly projecting splines 32 of the female member is 0.4 inches on the diameter. One skilled in the art recognizes this interference is application specific, that is, dependent upon the energy dissipated, the materials selected, the size of the members, etc. One skilled in the art also recognizes the material and thickness are application specific and other materials, such as aluminum, steel alloys, or composite shafts, may be used as may be desirable, based on weight, size, power, and other parameters. In a preferred embodiment, these parameters are selected to create an assembly which expands the female shaft 14 with a force less than 20,000 lbs.
In an alternative embodiment (not shown), each the male and female members 12 and 14 have splines formed on the walls of tubes in a more traditional known manner, such as forging or broaching. The radial deformations of the female tube described above occurs due to careful design of the tube cross section thicknessess to enable radial expansion of the female member adjacent the splines. This may require machining of the outside diameter of the female member to reduce the thickness and therefore the radial strength thereof during such a crash. Alternatively, other means may be used to weaken the female member thereat, such as by cutting axial slots in the female member to facilitate the radial expansion. Similar measures may be taken on the male member to facilitate radial compression thereof.
In a further alternative embodiment (not shown), the splines extend along the entire length of the male and female members, and therefore the transition from the splines to the unsplined portion as described above and illustrated in the figures is not provided. The female member has a reduced portion which engages the forward end of the splines of the male member during compression of the driveshaft. This reduced portion comprises a circumferentially formed depression rolled into the outwardly projecting splines (the female tube is essentially an annular tube in this region having an inside diameter providing the 0.4 inch interference described above). During a crash, the male member thus engages the depression, and the forward end of the male member causes expansion of the reduced portion, or the male member is compressed within the reduced portion of the female member in a manner similar to that described above.
In a further alternative embodiment, the splines likewise extend along the entire length of both the male and female members. The interference described above for expanding the female member is created by outwardly deforming the splines of the male member. In such an embodiment, each of the splines is filled with a material (such as by welding a filler in place between each spline), or integrally forming projections in the tube between splines. In one embodiment, male tube is formed from a flat sheet of metal. The projections are formed by pressing alternating longitudinal depressions in the flat sheet of sheet metal and rolling the sheet into a cylinder and welding the seam. In this embodiment, the longitudinal depressions (the splines) have a break formed therein and therefore a transition is formed therein to cause the interference described above. These projections may alternatively be formed by any other known manner, including swaging (a female tube), extrusion, hydroforming, or any known technique.
In a further alternative embodiment (not shown), the transition 26 comprises an circumferential projection (or series of axially spaced projections) formed in the male tube, as opposed to the cylindrical unsplined portion 21 shown in FIGS. 1 and 2. This circumferential projection likewise comprises a larger outside diameter in the male member (between the splines) so the female member deforms outwardly during a crash, thereby dissipating some crash energy. Alternatively, the outward projections are deformed inwardly by the splines of the female member during a crash.
In another alternative embodiment, the driveshaft assembly 10 illustrated in FIGS. 1 and 2 includes a male tube 12 having a closed front end (not shown) engaged with the female tube 14 . The female tube 14 has a closed end at the weld yoke 24 . In this embodiment, during the crash, the air within the cavity 27 defined by the closed end of the male tube and the inside of the female tube is compressed, absorbing a further amount of energy. Likewise, the female cavity may be filled with another compressible medium, such as a fluid, gas, or resilient material, such as rubber, or a frangible material, such as a carbon graphite tube, and thereby absorb additional energy.
One skilled in the art recognizes the driveshaft may comprise other shapes, such as square, or any other slidably engaged geometry of axially slidably engaged shafts, one of the members having a section which interferes with the other member to absorb energy yet allowing collapse of the shaft during a crash. In such an embodiment, the noncircular shape transmits torque in a known manner and therefore splines are not required.
The forms of the invention shown and described herein constitute the preferred embodiments of the invention; they are not intended to illustrate all possible forms thereof. The words used are words of description rather than of limitation, and various changes may be made from that which is described here without departing from the spirit and scope of the invention. | A driveshaft assembly includes a male shaft and a female shaft slidably engaged with the male shaft. The shafts absorb energy during axial deformation of the driveshaft while substantially maintaining radial alignment of the male and female shafts. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to processing data for visual presentation, wherein the processing includes the creation or manipulation of graphic objects prior to presenting the processed data on a specific display system. More particularly, the present invention includes subject matter wherein the processed data is displayed to a user as one or more nested treemaps showing a relationship between two or more variables. The present invention further includes color information processing wherein the color and shading in the treemap is calculated to visually distinguish a nested treemap from the parent treemap or other nested treemaps.
BACKGROUND OF THE INVENTION
[0002] Conceptually, much of the world's information can be organized as a hierarchy. Brian Johnson & Ben Shneiderman, Tree - Maps: A Space - Filling Approach to the Visualization of Hierarchical Information Structures (April 1991), at ftp://ftp.cs.umd.edu/pub/hcil/Reports-Abstracts-Bibliography/91-06html/91-06.html (last visited Oct. 8, 2004) (incorporated herein by reference). For many years, the most common methods for presenting hierarchical information were listings, outlines, and tree diagrams. Id. A tree diagram is a widely-used computer data structure that emulates a tree structure with a set of linked “nodes.” As used herein, the term “node” includes any data structure unit having either data or a link to another data structure unit. Each node may have one or more “child nodes,” which are below it in the tree. Naturally, the node of which a node is a child is called its “parent node.” A child node has at most one parent node. A child node without a parent node is called the “root node.” Generally, a tree diagram has only one root node. A node having only data and no child node is called a “leaf node,” while any node that is neither a root node nor a child node is referred to generally as an “interior” node. See, generally, Wikipedia, at http://en.wikipedia.org/wiki/Tree data structure (last visited Oct. 13, 2004) (incorporated herein by reference); Ben Shneiderman, Tree visualization with Tree - maps: A 2- D space filling approach (Jun. 18, 1991), ftp://ftp.cs.umd.edu/pub/hcil/Reports-Abstracts-Bibliography/91-03html/91-03.html (last visited Oct. 8, 2004) (incorporated herein by reference) [hereinafter Shneiderman I]. The amount of space required to display listings, outlines, and tree diagrams, though, is directly proportional to the amount of information displayed. Thus, the conventional rooted display methods generally make poor use of display space or hide vast amounts of information from users. See Johnson & Shneiderman, supra.
[0003] “Treemaps” first appeared in the early 1990's as an alternative to the conventional presentation methods. See, e.g., Ben Shneiderman, Treemaps for space - constrained visualization of hierarchies (Dec. 26, 1998), at http://www.cs.umd.edu/hcil/treemap-history/ (last updated May 18, 2004) (last visited Oct. 8, 2004) (incorporated herein by reference) [hereinafter Shneiderman II]; Shneiderman I, supra; Johnson & Shneiderman, supra. A treemap “makes 100% use of the available display space, mapping the full hierarchy onto a rectangular region in a space-filling manner. This efficient use of space allows very large hierarchies to be displayed in their entirety and facilitates the presentation of semantic information.” Johnson & Shneiderman, supra. As Johnson & Shneiderman explain, treemaps “partition the display space into a collection of rectangular bounding boxes representing the tree structure. The drawing of nodes within their bounding boxes is entirely dependent on the content of the nodes, and can be interactively controlled. Since the display size is user controlled, the drawing size of each node varies inversely with the size of the tree (i.e., # of nodes). Trees with many nodes (1000 or more) can be displayed and manipulated in a fixed display space.” Id. Thus, treemaps provide access to detail while keeping the global context. Harsha Kumar et al., Visual Information Management for Network Configuration (June 1994), at ftp://ftp.cs.umd.edu/pub/hcil/Reports-Abstracts-Bibliography/94-07html/94-07.html (last visited Oct. 8, 2004). Screen space utilization is maximized, and scrolling and panning are not required. Id. The number of nodes that can be displayed in a treemap is an order of magnitude greater than that by a traditional tree diagram. Id.
[0004] Originally developed to visualize large directory structures on a hard disk, see Shneiderman I, supra; Johnson & Shneiderman, supra, treemaps have evolved considerably, and now include rich feature sets that support flexible hierarchies, color binning, improved color setting, and aggregation. Shneiderman I, supra. Several treemap variants also have evolved to address some of the shortcomings of the original implementation. Two popular variants are the “nested” (or “clustered”) and “squarified” treemap, both of which employ an algorithm for minimizing aspect ratios of each bounding box displayed in a treemap. See, e.g., Benjamin B. Bederson et al., Ordered and Quantum Treemaps: Making Effective Use of 2 D Space to Display Hierarchies (October 2002), at ftp://ftp.cs.umd.edu/pub/hcil/Reports-Abstracts-Bibliography/2001-18html/2001-18.pdf (last visited Oct. 8, 2004) (incorporated herein by reference). Treemaps have been used to provide an efficient visual presentation of a diverse variety of information, ranging from financial analysis to sports reporting. Id. See also Shneiderman I, supra; Map of the Market, http://www.smartmoney.com/marketmap (last visited Oct. 13, 2004). In an enterprise computing system, system administrators also need to monitor large collections of data about the performance of an entire network topology. Much like tree data structures, a network topology generally consists of a root node and one or more linked nodes. Thus, treemaps are ideal for depicting network performance data. Typically, such performance data consists of five to ten properties (such as central processing unit (CPU) usage, goal attainment, name, and number of deployed applications) for each node in the topology. The number of nodes in any given topology can vary, but the number typically ranges from ten to one thousand. FIG. 1 is a nested treemap of an exemplary network topology comprised of twenty-three network nodes. As described above, the illustrative treemap in FIG. 1 partitions the display space into rectangular bounding boxes, so that each node in the network is represented by a corresponding rectangular bounding box 10 . As used herein, a “bounding box” refers to any rectangular box that circumscribes an area in a treemap that is proportional to the value of one property of the nodes displayed in the treemap. Thus, in FIG. 1 , the treemap is partitioned into twenty-three bounding boxes, and the area of each bounding box is proportional to one property of each network node. The treemap in FIG. 1 also illustrates the concept of nested treemaps. In FIG. 1 , seven nodes have been grouped together as a “cluster” and displayed as nested treemap “WebGroup,” and another six nodes have been clustered together and displayed as a second nested treemap designated as “Cluster A.”
[0005] Hierarchical information comprises both structural (also referred to as “organizational”) information associated with the hierarchy, and content information associated with each node in the hierarchy. Johnson & Shneiderman, supra. Generally, treemaps rely heavily on visual cues such as color and size to present content information to a user. Id. A color gradient often represents a given property of a given node, while bounding box size represents another property of the node. Thus, in the treemap of the exemplary network topology of FIG. 1 , the shading of each bounding box might represent each node's CPU usage, while the area of each bounding box might be proportional to the number of applications deployed on each node. Or, if a treemap represents stock market data, a color gradient from red to black to green might represent a particular stock's performance for a given day, while box size might represent trading volume. Related nodes, such as stocks within a particular sector, often are grouped together and displayed in a nested treemap within a parent treemap. Conventional nested treemaps, though, do little to visually differentiate nested treemaps from each other.
[0006] The invention described in detail below addresses this shortcoming in the art. In particular, it is an object of the present invention to improve processing of color information and shading in a treemap so that a nested treemap is visually distinguishable from a parent treemap or other nested treemaps. This and other objects of the invention will be apparent to those skilled in the art from the following detailed description of a preferred embodiment of the invention.
SUMMARY OF THE INVENTION
[0007] The inventive process described below comprises an improved process for displaying hierarchical information in a treemap by associating a different color with each nested treemap in a parent treemap, and generating a gradient for each color to preserve the representative value of varying shades.
[0008] In general, a system administrator or other user divides the hierarchical information into clusters of nodes, designates a primary weight and a secondary weight for each cluster, and designates a base color for each cluster. The inventive process comprises dividing the range of each cluster's secondary weight into bins, adjusting each cluster's base color to create a distinguishing gradient of the base color, assigning a distinguishing gradient to each bin, and drawing a nested treemap for each cluster so that each nested treemap has the cluster's base color and each node in the cluster is represented by a bounding box having a distinct gradient of the cluster's base color.
BRIEF DESCRIPTION OF DRAWINGS
[0009] The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be understood best by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
[0010] FIG. 1 is a treemap of an exemplary network topology;
[0011] FIG. 2 depicts an exemplary network of prior art hardware devices;
[0012] FIG. 3 is a schematic of a computer memory in which the present invention resides;
[0013] FIG. 4 illustrates the inventive process of mapping a color to a treemap;
[0014] FIG. 5 illustrates a JAVA implementation of generating gradient waypoints;
[0015] FIG. 6 illustrates a JAVA implementation of generating color gradients for a range of secondary weights; and
[0016] FIG. 7 illustrates a JAVA implementation of generating a color gradient that is proportional to two bounding colors.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] The principles of the present invention are applicable to a variety of computer hardware and software configurations. The term “computer hardware” or “hardware,” as used herein, refers to any machine or apparatus that is capable of accepting, performing logic operations on, storing, or displaying data, and includes without limitation processors and memory; the term “computer software” or “software,” refers to any set of instructions operable to cause computer hardware to perform an operation. A “computer,” as that term is used herein, includes without limitation any useful combination of hardware and software, and a “computer program” or “program” includes without limitation any software operable to cause computer hardware to accept, perform logic operations on, store, or display data. A computer program may, and often is, comprised of a plurality of smaller programming units, including without limitation subroutines, modules, functions, methods, and procedures. Thus, the functions of the present invention may be distributed among a plurality of computers and computer programs. The invention is described best, though, as a single computer program that configures and enables one or more general-purpose computers to implement the novel aspects of the invention. For illustrative purposes, the inventive computer program will be referred to below as the “TreeMap Program.”
[0018] Additionally, the TreeMap Program is described below with reference to an exemplary network of hardware devices, as depicted in FIG. 2 . A “network” comprises any number of hardware devices coupled to and in communication with each other through a communications medium, such as the Internet. A “communications medium” includes without limitation any physical, optical, electromagnetic, or other medium through which hardware or software can transmit data. For descriptive purposes, exemplary network 200 has only a limited number of nodes, including workstation computer 205 , workstation computer 210 , server computer 215 , and persistent storage 220 . Network connection 225 comprises all hardware, software, and communications media necessary to enable communication between network nodes 205 - 220 . Unless otherwise indicated in context below, all network nodes use publicly available protocols or messaging services to communicate with each other through network connection 225 .
[0019] TreeMap Program (TMP) 300 typically is stored in a memory, represented schematically as memory 320 in FIG. 3 . In the preferred embodiment, TMP 300 is implemented as a JAVA program comprising a base class, designated as TreeMapNode 340 in FIG. 3 , and two classes that extend TreeMapNode 340 , namely TreeMap 350 and TreeMapWeight 360 . TreeMap 350 represents non-leaf nodes in a hierarchy, while TreeMap 360 represents leaf nodes. The term “memory,” as used herein, includes without limitation any volatile or persistent medium, such as an electrical circuit, magnetic disk, or optical disk, in which a computer can store data or software for any duration. A single memory may encompass and be distributed across a plurality of media. Thus, FIG. 3 is included merely as a descriptive expedient and does not necessarily reflect any particular physical embodiment of memory 320 . As depicted in FIG. 3 , though, memory 320 may include additional data and programs. Of particular import to TMP 300 , memory 320 may include administration program 330 , getGradientWayPoints function 370 , generateGradient function 380 , getshade function 390 , and user data 395 , with which TMP 300 interacts.
[0020] In such an embodiment, administration program 330 provides an interface through which a system administrator can configure and monitor network nodes. In particular, administration program 330 allows a system administrator to monitor the performance of any network node. Typically, administration program 330 collects data such as CPU usage, goal attainment, name, and number of deployed applications for each network node. For illustrative purposes, the following discussion assumes that administration program 330 directly measures the performance of network nodes, but as noted above, such a function easily could be delegated to a more specialized programming unit.
[0021] FIG. 4 illustrates the inventive process when implemented as TMP 300 , in conjunction with administration program 330 . Administration program 330 allows a system administrator to divide the network nodes into clusters ( 410 ), and store such a division in memory as user data 395 . Such a division may be arbitrary, but to realize the full benefits of the inventive process each cluster should include logically related nodes. Thus, as used herein, a “cluster” is any number of nodes that are treated collectively as a unit for purposes of displaying data in a treemap. For example, one cluster might include all web server nodes, as indicated in FIG. 1 by the “WebGroup” cluster, while another includes all file server nodes. Through administration program 330 , the system administrator also designates which node properties a treemap should display, such as CPU usage and the number of applications deployed, and which property the treemap should display as a primary weight and a secondary weight. As used herein, the “primary weight” refers to the property that a treemap displays as a bounding box having an area that is proportional to the property, and the “secondary weight” refers to the property that the treemap displays as a color gradient representative of the property.
[0022] Administration program 330 also allows the system administrator to choose a color for each cluster of nodes ( 420 ), which is stored in memory 320 as user data 395 . In one embodiment, the system administrator designates a single “base” color, which identifies the “middle” of a desired range of color gradients for a node cluster. White and black then become the extremes of the range. Alternatively, the system administrator chooses a “low” color and a “high” color, which represent the extremes of the desired color gradient for each cluster. In two-color embodiment, black is the middle color. In either embodiment, though, the system administrator or administration program 330 identifies each color as a triplet in a Red, Green, Blue (RGB) color model. As used herein, an RGB color model is any additive color model in which red, green, and blue light are combined in various ways to create other colors. In practice, every color in an RGB color model is identified as a triplet of numbers. Each value in an RGB triplet is a number between 0 and 255, representing the intensity of the primary red, green, and blue colors, respectively, in a given color. Although many color models are available to choose from, the RGB color model is a convenient and commonly used model with which most administrators should be familiar.
[0023] When a system administrator or other user invokes TMP 300 from administration program 330 , administration program 330 creates an instance (“instantiates”) of TreeMapNode 340 for each node cluster. Each instance of TreeMapNode 340 then loads the preferred color for its node from user data 395 , instantiates TreeMap 350 for each internal node, and TreeMapWeight 360 for each leaf node.
[0024] Although the RGB color model is familiar to administrators, color gradients are more readily manipulated when modeled as a combination of Hue, Saturation, and Lightness (HSL). Thus, in one embodiment, TMP 300 converts each RGB triplet to an equivalent HSL triplet for easier manipulation ( 430 ). As used herein, “hue” refers to a particular color within the visible spectrum, as defined by its dominant wavelength. See, generally, Color Theory , httn://www.colorcube.com/articles/theory/theory.htm (2000) (last visited Oct. 12, 2004) (incorporated herein by reference). In short, hue distinguishes red from green from blue. “Lightness” (also sometimes referred to as “luminance” or “luminescence”) indicates the intensity of light per unit area of its source. See id. In general, “saturation” is the intensity of a color at any given lightness. Id. In an HSL color model, saturation is defined mathematically as the difference between the maximum of the equivalent RGB values and the minimum of the equivalent RGB values, or
saturation=max( R,G,B )−min( R,G,B ).
See, e.g., TheFreeDictionary.com, http://encyclopedia.thefreedictionary.com/HLS%20color%20space (last visited Oct. 12, 2004) (incorporated herein by reference). Similarly, lightness is defined as the average of the sum of the minimum and maximum, or
lightness=(max( R,G,B )+min( R,G,B ))/2
Id. Algorithms for converting RGB triples to HSL triples and vice versa are common and, thus, not discussed in detail here. See, e.g., The World Wide Web Consortium, CSS 3 Color Module: W 3 C Candidate Recommendation (Tantek Celic & Chris Lilley eds., May 14, 2003), http://www.w3.org/TR/css3-color/#hsl-color (last visited Oct. 12, 2004) (incorporated herein by reference).
[0025] After converting each RGB triple to an equivalent HSL triplet, TMP 300 then adjusts each saturation value to approximately 0.5 (or 50%), which provides a normalized, softer look to the color ( 440 ). Next, administration program 330 generates a dataset comprised of the network node properties specified by the system administrator, grouped hierarchically by cluster. TMP 300 then determines the maximum and minimum values of each property in the dataset, and divides the secondary weight range into bins. As used herein, the term “bin” refers to any discrete interval within the range of secondary weight values of any given cluster. In the embodiment described herein, each bin represents a percentage interval (e.g. 20%-30%) of the secondary weight range for a cluster of nodes. The system administrator may specify the number of bins through administrator program 330 , and save the number as user data 395 .
[0026] TMP 300 then generates color gradients at “waypoints” for the secondary weight range, so that the middle color is limited to a reasonable range. The function getGradientWayPoints 370 in FIG. 5 illustrates one JAVA implementation of the waypoint generation, in which the system administrator designates a low color and a high color. As FIG. 5 illustrates, getGradientWayPoints 370 creates waypoints by adjusting the lightness component of both the low color (“c1”) and the high color (“c2”) to create a gradient of each color that is closer to the middle color (which is black by default). Each waypoint color is then assigned to a specific percentage of the secondary weight range. In general, the waypoint percentages approximately represent the 39% and 61% lines of the secondary weight range.
[0027] After generating the color gradient for each waypoint, TMP 300 generates an array of color gradients for each remaining bin in the secondary weight range ( 450 ). The function generateGradient 380 in FIG. 6 illustrates one JAVA implementation of the gradient generation process. As FIG. 6 illustrates, generateGradient 380 accepts two arguments. The first, “Set wayPoints,” is a list of waypoints and associated color gradients, such as those generated by getGradientWayPoints 370 . The second argument, “int numShades” represents the number of color gradients to generate, which also is the number of secondary weight bins that the system administrator specifies in user data 395 . Function generateGradient 380 iterates through each bin, determining the difference between the waypoints surrounding each bin (“wpDiff”) and the proportional distance between the lower waypoint and the bin (“rangePct”), and then generating a gradient for each bin (“shade”). The function getShade 390 in FIG. 7 illustrates one JAVA implementation generating a gradient that is proportional to two bounding colors. As FIG. 7 illustrates, getShade 390 accepts three arguments. The first two arguments (“Color c1” and “Color c2”) represent the bounding colors, while the third argument (“float pct”) represents the desired adjustment as a percentage. As FIG. 7 illustrates, getShade 390 essentially just averages the RGB components of the two bounding colors. Alternatively, getShade 390 could directly adjust the lightness component of either bounding color to generate the desired gradient.
[0028] Finally, TMP 300 generates an index into the array of gradients that associates the secondary weight of each node with a color gradient in the array, calculates the appropriate size of bounding box to represent the primary weight of each node ( 460 ), and renders the treemap for the generated dataset ( 470 ).
[0029] A preferred form of the invention has been shown in the drawings and described above, but variant in the preferred form will be apparent to those skilled in the art. The preceding description is for illustration purposes only, and the invention should not be construed as limited to the specific form shown and described. The scope of the invention should be limited only by the language of the following claims. | The inventive process comprises and improved process for displaying hierarchical information in a treemap by associating a different color with each nested treemap in a parent treemap, and generating a gradient for each color to preserve the representative value of varying shades. In general, a user divides the hierarchical information into clusters of nodes, designates a primary weight and a secondary weight for each cluster, and designates a base color for each cluster. The inventive process then divides the range of each cluster's secondary weight into bins, adjusts each cluster's base color to create a distinguishing gradient of the base color, assigns a distinguishing gradient to each bin, and draws a nested treemap for each cluster so that each nested treemap has a cluster's base color and each node in the cluster is represented by a bounding box having a distinct gradient of the cluster's base color. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a divisional application of Ser. No. 10/804,070 filed on Mar. 19, 2004.
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT
[0002] The invention relates to a metal gasket, such as a cylinder head gasket, to be sandwiched between two members, for example a cylinder head and a cylinder block, of an internal combustion engine to seal therearound.
[0003] In case joint surfaces of a cylinder head and a cylinder block (cylinder body) of a vehicle are sealed, combustion gas, cooling water, lubricating oil and the like are sealed by sandwiching a cylinder head gasket therebetween.
[0004] To meet demands of reducing weight of an engine and a production cost, a cylinder head gasket has been changed to a simple structural cylinder head gasket formed of one or two metal base plates from a metal laminate type gasket including a plurality of metal base plates. Therefore, the constituent plates become one or two, usable materials are limited from the aspect of making an engine light, and the kind and number of sealing devices are also limited, which forces to use relatively simplified sealing devices.
[0005] Therefore, mainly for a cylinder head gasket, for example as shown in FIG. 13 , there has been proposed a gasket 2 , wherein a main bead 6 A and sub-beads 6 B linearly connected to the hem portions of the main bead 6 A are provided to a metal plate 2 so that surface pressures are generated concentrically at top portions of the main bead 6 A and the sub-beads 6 B to positively seal with large surface pressures (For example, Japanese Patent Publication (KOKAI) No. 11-230355, refer to page 2, FIG. 2).
[0006] Also, as a gasket formed of two plates, as shown in FIG. 14 , there has been proposed a metal laminate gasket for sealing a port of an intake-exhaust system of an engine, wherein a sectional shape of a circular bead 4 surrounding the port 2 is formed in a wave shape having two continuous mountain-shape portions 4 a, 4 b to project mutually in opposite directions from flat portions of a metal plate 1 , and the two metal plates are laminated in such a manner that the top portions of the mountain-shape portions 4 a of the circular beads 4 abut against each other. Therefore, the metal plate 1 is provided with the circular bead 4 having two heights of the mountain-shape portions, and the circular beads 4 of the respective layers are sufficiently subjected to an elastic deformation to thereby effectively prevent leaking of a medium to be sealed (For example, Japanese Patent Publication (KOKAI) No. 2002-54502, refer to page 3, FIG. 2).
[0007] However, in the gaskets having such wave-form circular beads, while they are effective for concentrating the surface pressure or enlarging the crushed margins, the rigidity is basically determined by the sectional shape of the beads formed on the plate.
[0008] On the other hand, in a cylinder head gasket and the like, even in case the same gasket is used to seal between the same engine members, the sealing performance required by the kind of a hole to be sealed becomes different. For example, in a hole for a cylinder bore, it is required to seal a combustion gas having a high temperature and a high pressure, while in a liquid hole for circulating cooling water and engine oil, it is required to seal a liquid having a comparatively low temperature and pressure.
[0009] Also, from a structural reason of an engine, there are generated different surface pressures in a hole for a cylinder bore surrounded by bolt holes for tightening bolts and a liquid hole located on an outer side so that the pressing forces by the tightening bolts are only applied to one side thereof.
[0010] In the metal gasket as described above, in case a bead is simply provided, the rigidity of the bead is determined by the shape of the bead, material characteristics of metal of a base plate and a thickness of the base plate. Therefore, the design freedom is limited, and it is difficult to provide the optimum sealing performance with respect to the respective holes to be sealed.
[0011] Especially, since a high surface pressure is required around the hole for the cylinder bore, in order not to damage the engine members made of a relatively soft aluminum alloy, it is difficult to use a metal base plate having a high rigidity. On the other hand, there is also a problem that a sufficient rigidity can not be obtained with the conventional shape and arrangement of the bead.
[0012] Also, as shown in FIG. 14 , in the gasket where the top portions 4 a of the mountain-shapes of the wave-forms in a two plate structure abut against each other, in case the abutting beads are mis-aligned, since a predetermined compression rigidity of the beads 4 may not be obtained, it is required to carry out the precise alignment of the abutting beads 4 .
[0013] However, in a cylinder head gasket and the like having a fine bead of a width less than 3 mm, the positioning is actually difficult, so that an advanced technique is required.
[0014] In view of the above, the present invention has been made, and an object of the invention is to provide a metal gasket of a two plate structure excellent in sealing ability, such as a cylinder head gasket, wherein sub-beads are respectively provided around main beads disposed to respective metal base plates for sealing a hole to be sealed and the sub-beads abut against each other so that an adequate bead rigidity can be obtained by constraining the deformation in a radial direction of a main bead of one metal base plate by the sub-bead of the other metal base plate. Thus, the optimum surface pressure distribution can be generated around the hole for the cylinder bore or the like and maintained.
[0015] Further objects and advantages of the invention will be apparent from the following description of the invention.
SUMMARY OF THE INVENTION
[0016] In order to attain the above objects, a gasket of the invention is formed of a first metal base plate provided with a first main bead and a second metal base plate provided with a second main bead, wherein the first main bead and the second main bead are disposed back to back to project outwardly around a hole to be sealed. The gasket comprises a first inner peripheral side sub-bead smaller than the first main bead disposed on an inner peripheral side of the first main bead; a first outer peripheral side sub-bead smaller than the first main bead disposed on an outer peripheral side of the first main bead; a second inner peripheral side sub-bead smaller than the second main bead disposed to abut against the first inner peripheral side sub-bead on an inner peripheral side of the second main bead; and a second outer peripheral side sub-bead smaller than the second main bead disposed to abut against the first outer peripheral side sub-bead on an outer peripheral side of the second main bead.
[0017] Incidentally, it is sufficient that the sub-beads abut against each other under a state where the metal gasket is set. Therefore, the abutment between the sub-beads may include a case where the sub-beads do not abut against each other before they are pressed by a predetermined pressing force, i.e. in an initial shape without being pressed. For example, in the cylinder head gasket, in case the gasket itself is in an initial state, the sub-beads may not abut against each other. It is sufficient that when the gasket is sandwiched between a cylinder head and a cylinder block and tightened by the tightening bolts with a predetermined pressing force, side portions of the sub-beads may abut against each other on either inner side or outer side.
[0018] According to the structure, diversification and fine adjustment of the rigidity of the main beads can be attained by correlating the deformations of one main bead and the other main bead with abutments of the sub-beads, and the accuracy of positioning of the two metal base plates can be improved. In other words, the periphery of one main bead, which has a large deformation quantity in the widthwise direction, can be constrained through abutments of the sub-beads provided on the outer peripheral side and inner peripheral side of the main beads. Thus, the rigidity can be elevated by constraining a displacement in the widthwise direction of one main bead.
[0019] Moreover, since the degree of the constraint in the radial direction of one main bead can be adjusted by the shape (here, also including a size) of the other main bead and the material characteristics and plate thickness of the metal base plate, a multiple of surface pressures can be generated through the combination of the two main beads. Thus, a more adequate sealing line corresponding to a hole to be sealed can be formed to thereby improve the sealing ability of the gasket.
[0020] Also, since the sub-beads of one metal base plate and the sub-beads of the other metal base plate are disposed to abut against each other in their side portions, the sub-beads guide each other to position themselves. Thus, the two sheets of the metal base plates can be easily and precisely aligned, and a desired sealing surface pressure can be positively obtained through combination of the beads.
[0021] Then, the mutual abutments between the sub-beads are carried out by at least one of an abutment between the first inner peripheral side sub-bead and the second inner peripheral side sub-bead and an abutment between the first outer peripheral side sub-bead and the second outer peripheral side sub-bead, through the abutments of the beads formed inwardly respectively. Or, at least one of the abutment between the first inner peripheral side sub-bead and the second inner peripheral side sub-bead and the abutment between the first outer peripheral side sub-bead and the second outer peripheral side sub-bead is carried out through an abutment by fitting one bead into the other bead.
[0022] Also, at least one of the first inner peripheral side sub-bead, the second inner peripheral side sub-bead, the first outer peripheral side sub-bead and a second outer peripheral side sub-bead is formed of a plurality of beads. Thus, the constraint in the radial direction can be elevated and the positioning accuracy can be improved.
[0023] Then, at least one of the first inner peripheral side sub-bead, the second inner peripheral side sub-bead, the first outer peripheral side sub-bead and the second outer peripheral side sub-bead is intermittently provided in the circumferential direction, so that the strength of the binding force can be easily adjusted.
[0024] In case the sealing is carried out by half beads, in a gasket to attain the above objects, formed of a first metal base plate and a second metal base plate, wherein a first main half bead of the first metal base plate and a second main half bead of the second metal base plate are disposed back to back with a projected portion outward, respectively, around a hole to be sealed, a first outer peripheral side sub-bead smaller than the first main half bead is provided on an outer peripheral side of the first main half bead and a second outer peripheral side sub-bead smaller than the second main half bead is disposed to abut against a side portion of the first outer peripheral sub-bead in a side portion thereof on an outer peripheral side of the second main half bead.
[0025] Also, in the half bead metal gasket, the abutment between the first outer peripheral side sub-bead and the second outer peripheral side sub-bead is structured by the abutment of the side portions of the beads projected inward; or the abutment between the first outer peripheral side sub-bead and the second outer peripheral side sub-bead is structured by fitting one bead into the other bead.
[0026] Further, at least one of the first outer peripheral side sub-bead and the second outer peripheral side sub-bead is discontinuously or intermittently provided in a circumferential direction, so that the strength of the binding force can be easily adjusted.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a partial perspective view with a section showing a cylinder head gasket of a first embodiment according to the invention;
[0028] FIG. 2 is a partial perspective view with a section showing another example of a cylinder head gasket of the first embodiment according to the invention;
[0029] FIG. 3 is a partial sectional view showing a cylinder head gasket of a second embodiment according to the invention;
[0030] FIG. 4 is a partial sectional view showing a cylinder head gasket of another example of the second embodiment according to the invention;
[0031] FIG. 5 is a partial sectional view showing a cylinder head gasket of a third embodiment according to the invention;
[0032] FIG. 6 is a partial sectional view showing a cylinder head gasket of another example of the third embodiment according to the invention;
[0033] FIG. 7 is a partial perspective view with a section of a cylinder head gasket of a fourth embodiment according to the invention;
[0034] FIG. 8 is a partial sectional view showing a cylinder head gasket of another example of the fourth embodiment according to the invention;
[0035] FIG. 9 is a partial sectional view showing a cylinder head gasket of a fifth embodiment according to the invention;
[0036] FIG. 10 is a partial sectional view showing a cylinder head gasket of another example of the fifth embodiment according to the invention;
[0037] FIG. 11 is a partial sectional view showing a cylinder head gasket of a sixth embodiment according to the invention;
[0038] FIG. 12 is a plan view of a cylinder head gasket of an embodiment according to the present invention;
[0039] FIG. 13 is a partial sectional view showing a conventional gasket; and
[0040] FIG. 14 is a partial sectional view showing a conventional metal gasket.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0041] Next, a cylinder head gasket, as an example, of an embodiment of a metal gasket according to the present invention will be explained with reference to the accompanying drawings.
[0042] As shown in FIGS. 1 through 12 , metal gaskets 1 and 1 A of the embodiments according to the invention are cylinder head gaskets to be sandwiched between a cylinder head and a cylinder block (cylinder body) of an engine to seal a combustion gas of high temperature and high pressure from cylinder bores, and a liquid, such as cooling water or cooling oil, flowing through a cooling water path or a cooling oil path.
[0043] Incidentally, FIGS. 1 through 12 are schematic views, wherein dimensions and horizontal to vertical ratios of a plate thickness, a bead, a coating film and the like of the cylinder head gaskets 1 , 1 A are different from the real measurements, so that sealing portions are exaggerated, which makes them easily understandable.
[0044] As shown in FIGS. 1 through 6 , FIGS. 7 through 11 , and FIG. 12 , cylinder head gaskets 1 , 1 A according to the present invention include two plates, i.e. a first metal base plate 10 and a second metal base plate 20 , formed of an annealed stainless steel, processed stainless steel (spring steel plate), soft iron plate or the like. These metal base plates 10 , 20 are produced in conformity with the shape of an engine member, such as a cylinder block, and provided with holes 2 for cylinder bores, liquid holes 3 for circulating cooling water and engine oil, bolt holes 4 for tightening bolts and the like.
[0045] In the present invention, in case a main bead is formed of a full bead, a first main bead 11 of the first metal base plate 10 and a second main bead 21 of the second metal base plate 20 are disposed back to back, i.e. aligned, around the hole 2 for the cylinder bore to be sealed so that both beads project outward, respectively.
[0046] Also, as shown in FIGS. 1 through 6 , in the first metal base plate 10 , a first inner peripheral side sub-bead 12 smaller than the first main bead 11 is provided on an inner peripheral side of the first main bead 11 , and a first outer peripheral side sub-bead 13 smaller than the first main bead 11 is provided on an outer peripheral side of the first main bead 11 , respectively.
[0047] Also, in the second metal base plate 20 , a second inner peripheral side sub-bead 22 smaller than the second main bead 21 is provided to abut against the first inner peripheral side sub-bead 12 on the inner peripheral side of the second main bead 21 , and a second outer peripheral side sub-bead 23 smaller than the second main bead 21 is provided to abut against the first outer peripheral side sub-bead 13 on the outer peripheral side of the second main bead 21 .
[0048] In the first embodiment as shown in FIGS. 1 and 2 , the abutment between the first inner peripheral side sub-bead 12 and the second inner peripheral side sub-bead 22 and the abutment between the first outer peripheral side sub-bead 13 and the second outer peripheral side sub-bead 23 are carried out, respectively, such that the respective side portions of mutually inward projecting beads abut against each other.
[0049] While the first main bead 11 and the second main bead 21 normally have different shapes (including sizes), they may be the same shape. When the first main bead 11 and the second main bead 21 have the same shape, since there may be a temperature difference between the first metal base plate 10 and the second metal base plate 20 , the sub-beads 12 , 13 , 22 , 23 mainly play a role for mutually positioning the metal base plates 10 and 20 though there is deformation constraint of the main beads 11 , 21 .
[0050] In FIG. 1 , the first main bead 11 and the second main bead 21 have different shapes, and the sub-beads 12 , 13 , 22 , 23 have a trapezoidal shape. In FIG. 2 , the first main bead 11 and the second main bead 21 have the same shape, and the sub-beads 12 , 13 , 22 , 23 have a circular arc shape.
[0051] Also, in a second embodiment as shown in FIGS. 3 and 4 , a first inner peripheral side sub-bead 12 abuts against a second inner peripheral side sub-bead 22 , and a first outer peripheral side sub-bead 13 abuts against a second outer peripheral side sub-bead 23 . The abutments are made such that one bead enters the other bead to fit each other.
[0052] In FIG. 3 , a first main bead 11 and a second main bead 21 and respective sub-beads 12 , 13 , 22 , 23 are made in a trapezoidal shape. In FIG. 4 , the first main bead 11 and the second main bead 21 and the respective sub-beads 12 , 13 , 22 , 23 are made in a circular arc shape.
[0053] In a third embodiment of the invention as shown in FIGS. 5 and 6 , at least one of a first inner peripheral side sub-bead 12 , a second inner peripheral side sub-bead 22 , a first outer peripheral side sub-bead 13 and a second outer peripheral side sub-bead 23 is formed of a plurality of beads.
[0054] In FIG. 5 , the second outer peripheral side sub-bead is formed of two beads 23 so that the first outer peripheral side sub-bead 13 is sandwiched therebetween. In FIG. 6 , further, the first inner peripheral side sub-bead is formed of two beads 12 so that the second inner peripheral side sub-bead 22 is sandwiched therebetween. The number of the sub-beads may be two to three, if there is enough room to provide. There is no specific limitation.
[0055] In all structures of FIGS. 1 through 6 , the sub-beads 12 , 13 , 22 , 23 may be provided around the whole circumference in the circumferential direction, or may be discontinuously or intermittently provided. With the length and the position of the sub-beads, the magnitude of the constraint (strength) in a radial direction of the main bead 11 (or 21 ) can be finely adjusted.
[0056] Incidentally, an example of the dimensions of parts of the gasket will be shown hereunder. In case a diameter of a hole 2 for a cylinder bore is about 50 mm-90 mm, a thickness of the first metal base plate 10 and the second metal base plate 20 is 0.10 mm-0.40 mm, respectively; a height of the trapezoidal beads of the first main bead 11 and the second main bead 21 is 0.05 mm-0.30 mm; a bead width (length of the hem portion) is 1.0 mm-5.0 mm; a bead height of the trapezoidal beads of the first inner peripheral side sub-bead 12 and the second inner peripheral side sub-bead 22 is 0.01 mm-0.15 mm, and a width of the beads thereof is 0.5 mm-3.0 mm; and a height of the trapezoidal beads of the second outer peripheral side sub-bead 13 and the second outer peripheral side sub-bead 23 is 0.01 mm-0.15 mm, and a bead width thereof is 1.0 mm-3.0 mm.
[0057] In the present invention, in case the main beads are formed of half beads, a first main half bead 11 A of the first metal base plate 10 and a second main half bead 21 A of the second metal base plate 20 are disposed back to back, i.e. aligned, to project outwardly around the hole 2 for the cylinder bore to be sealed.
[0058] Also, as shown in FIGS. 7 and 8 , the first metal base plate 10 is provided with a first outer peripheral side sub-bead 13 smaller than the first main half bead 11 A on an outer peripheral side of the first main half bead 11 A, and the second metal base plate 20 is provided with a second outer peripheral side sub-bead 23 smaller than the second main half bead 21 A to abut against the first outer peripheral side sub-bead 13 on the outer peripheral side of the second main half bead 21 A.
[0059] In the fourth embodiment as shown in FIGS. 7 and 8 , the abutment between the first outer peripheral side sub-bead 13 and the second outer peripheral side sub-bead 23 is carried out by allowing the respective side portions of beads projecting inward to abut against each other.
[0060] The first main half bead 11 A and the second main half bead 21 A are normally formed in a different shape (including size), but they may have the same shape. In case they have the same shape, since the temperature of the first metal base plate 10 may be different from that of the second metal base plate 20 , the sub-beads 13 , 23 mainly play a role for mutually positioning the metal base plates 10 and 20 though there is deformation constraint of the main half beads 11 A, 21 A.
[0061] In FIG. 7 , the first main half bead 11 A and the second main half bead 21 A have a different shape, respectively, and the sub-beads 13 , 23 have a trapezoidal shape; and in FIG. 8 , the first main half bead 11 A and the second main half bead 21 A have the same shape and the sub-beads 13 , 23 have a circular arc shape.
[0062] In a fifth embodiment as shown in FIGS. 9 and 10 , the abutment between the first outer peripheral side sub-bead 13 and the second outer peripheral side sub-bead 23 is carried out by fitting one bead into the other bead. In FIG. 9 , the respective sub-beads 13 , 23 are formed in a trapezoidal shape; and in FIG. 10 , the respective sub-beads 13 , 23 are formed in a circular arc shape.
[0063] In an eighth embodiment as shown in FIG. 11 , at least one of the first outer peripheral side sub-bead 13 and the second outer peripheral side sub-bead 23 is formed of plural beads. In FIG. 11 , the first outer peripheral side sub-bead is formed of two beads 13 to sandwich the second outer peripheral side sub-bead 23 . The number of the sub-beads may be two to three, if there is an enough space, and there is no specific limitation.
[0064] In all structures of FIGS. 7 through 11 , the sub-beads 13 , 23 may be provided around the whole circumference in the circumferential direction, or may be intermittently provided. By the lengths and the positions of the sub-beads, the magnitude of the constraint (strength) in a radial direction of the main half-bead 11 A (or 21 A) can be finely adjusted.
[0065] According to the cylinder head gaskets 1 , 1 A having the structures as described above, the periphery of one main bead 11 ( 11 A, 21 or 21 A), which has a large deformation quantity in the widthwise direction, can be constrained through abutment of the respective side portions of the sub-beads 12 , 13 , 22 , 23 provided on the outer peripheral side and inner peripheral side of the main beads 11 , 21 or the main half beads 11 A, 21 A. Thus, the rigidity of the one main bead 11 ( 21 , 11 A, or 21 A) can be increased.
[0066] Since the degree of the constraint in the radial direction of one main bead 11 ( 11 A, 21 , or 21 A) can be adjusted by the shape of the other main bead 21 ( 11 , 11 A or 21 A) and the material characteristics and plate thickness of the metal base plate 20 (or 10 ), a multiple of surface pressures can be generated through the combination of the main beads 11 , 21 or the main half beads 11 A, 21 A.
[0067] Also, since the sub-beads 12 , 13 of one metal base plate 10 and the sub-beads 22 , 23 of the other metal base plate 20 are disposed to abut against each other in their side portions, the sub-beads 12 , 13 , 22 , 23 guide each other to position themselves. Thus, the two sheets of the metal base plates 10 , 20 can be easily and precisely aligned. By improving accuracy of the alignment, a desired surface pressure can be positively obtained to thereby carefully respond to the sealing ability required with respect to the hole 2 for the cylinder bore and improve the sealing ability.
[0068] Since the sealing ability around a liquid hole 3 is not strict to the sealing ability around the hole 2 for the cylinder bore, a desired sealing ability can be obtained by providing a relatively simple bead 31 .
[0069] Therefore, the cylinder head gasket 1 having the structure as described above can respond precisely to the sealing ability required by the hole 2 for the cylinder bore and the sealing ability required by the liquid hole 3 , respectively. Thus, adequate sealing balances with respect to the respective portions of the metal gasket 1 or 1 A can be attained.
[0070] Incidentally, the present invention is not limited to only these embodiments. The present invention is also applied to metal gaskets for other use, such as an inlet manifold and an exhaust manifold, in addition to the cylinder head gasket.
[0071] As described hereinabove, according to the metal gasket of the invention, the periphery of one main bead, which has a large deformation quantity in the widthwise direction, can be constrained through abutment of the sub-beads provided on the outer peripheral side and inner peripheral side of the main beads. Thus, the rigidity of one main bead can be increased. Since the degree of the constraint in the radial direction of one main bead can be adjusted by the shape of the other main bead and the material characteristics and plate thickness of the metal base plate, multiple surface pressures can be generated through the combination of the two main beads.
[0072] Also, since the sub-beads of one metal base plate and the sub-beads of the other metal base plate are disposed to abut against each other in their side portions, the sub-beads guide each other to position themselves. Thus, the two sheets of the metal base plates can be easily and precisely aligned. By improving accuracy of the alignment, a desired surface pressure can be positively obtained.
[0073] Therefore, the sealing ability can be improved since the sealing abilities required for the respective holes to be sealed can be adequately dealt and the suitable sealing balances with respect to the various portions of the metal gasket can be attained.
[0074] While the invention has been explained with reference to the specific embodiments of the invention, the explanation is illustrative and the invention is limited only by the appended claims. | A metal gasket is formed by first and second metal base plates laminated together. The first metal base plate includes one first half bead around the hole, and a first outer sub-bead section. The first outer sub-bead section is smaller than the first half bead, and is provided outside the first half bead. The second metal base plate includes one second half bead around the hole to project in a direction opposite to the first half bead, and a second outer sub-bead section smaller than the second half bead and provided outside the second half bead. The second outer sub-bead section projects in a direction opposite to the second half bead. When the first and second metal base plates are assembled, the first and second half beads face opposite to each other, and the second outer sub-bead section abuts against the first outer sub-bead section. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119 to Korean Patent Application No. 10-2010-0119038, filed on Nov. 26, 2010, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to a routing method for wireless mesh networks and a wireless mesh network system using the same, and more particularly, a routing method for wireless mesh networks capable of acquiring a high throughput through opportunistic concurrent transmissions and a wireless mesh network system using the same.
BACKGROUND
[0003] Recent proliferation of IEEE 802.11 WLANs (Wireless local area networks) stems from its attractive features such as low chipset cost, ease of deployment, and sufficient bandwidth. As IEEE 802.11 WLANs becomes a dominant wireless access technology, it requires more efficient use of scarce wireless resources.
[0004] Distributed Coordination Function (DCF), the most popular MAC protocol for IEEE 802.11 WLANs, is very simple and its distributed operations show good performance in most environment. DCF which is based on CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) prohibits concurrent transmissions in order to avoid packet collisions and harmful interferences.
[0005] However, this basic collision protection scheme (CSMA/CA) may not fully utilize the wireless resources in terms of spatial reuse due to its conservative medium access control. If we adjust the transmission order and relative signal strength, we can successfully transmit multiple packets without the collision and channel error. We call this Capture Effect.
[0006] Previous wireless NICs (Network Interface Card) enables the PHY capture when an intended signal arrives until the middle of the preamble time of an interference signal. Of course, the SINR (Signal to Interference plus Noise Ratio) value of the intended signal must satisfy the required capture threshold. Recent MIM (Message in Message)-capable NICs such as Athelos increases the PHY capture probability by using enhanced preamble detection functionality. MIM-capable NICs can capture the intended signal with higher SINR (≈10 dB) even if the intended signal arrives after the preamble time of an interference signal.
[0007] This is shown in FIG. 1 . FIG. 1A shows PHY capture, and FIG. 1B shows MIM, respectively.
[0008] As shown in FIG. 1A , when an intended signal having high SINR of approximately 10 dB arrives within the preamble time of an interference signal, the intended signal can be captured.
[0009] With MIM function, an intended signal can be captured even though it arrives after the preamble time of an interference signal, as shown in FIG. 1B .
[0010] U.S. Pat. No. 5,987,033 is the related art for maximizing the PHY capture using MIM function. In U.S. Pat. No. 5,987,033, there are disclosed a receiver and a method for operating the receiver, for a station in a wireless local area network using a common wireless communication channel and employing a CSMA/CA protocol includes various modes. In normal mode, the receiver follows typical states in order to detect a message and demodulate data from the message properly. Meanwhile, a process implements a message-in-message (MIM) mode when an energy increase above a specified level is detected. While in the MIM mode, if a carrier is detected, the energy increase is caused by a new message; otherwise, the energy increase is caused by an interfering station. If the carrier is detected, the receiver begins retraining so that it can start receiving the new message as soon as the first message ends.
SUMMARY
[0011] An exemplary embodiment of the present invention provides a routing method for a sender for transmitting a packet in a wireless mesh network including the sender, a receiver, and a plurality of access points disposed between the sender and the receiver, the method comprising: determining available transmission paths between the sender and the receiver; calculating expected transmission values for the transmission paths when there are two or more available transmission paths; and, setting the transmission path having a minimum expected transmission value among the transmission paths as an actual transmission path of the packet, wherein, in the calculating of the expected transmission values, a sum of expected transmission counts, the expected transmission count being a reciprocal of multiplication of forward transmission success rate and backward transmission success rate of a communication link between the nodes disposed on the transmission paths, is calculated—the node means the sender, the receiver, or the access point—; and wherein, when a signal to interference plus noise ratio (SINR) value of the communication link in which a first access point transmits is equal to or more than a predetermined capture threshold if a second access point transmits concurrently with the first access point among the nodes disposed on the transmission paths, the second access point determines that the packet can be concurrently transmitted, and the expected transmitted count for the communication link in which the second access point transmits is multiplied by a constant smaller than 1 to calculate the expected transmission value.
[0012] The constant may be ½, the forward transmission success rate and the backward transmission success rate for each communication link may be calculated by the node configuring the communication link, and the sender may receive the expected transmission counts from the nodes to calculate the expected transmission value.
[0013] Another exemplary embodiment of the present invention provides a wireless mesh network system including a sender, a receiver, and a plurality of access points disposed between the sender and the receiver: wherein, available transmission paths between the sender and the receiver are determined when the sender intends to send a packet to the receiver; expected transmission values are calculated for the transmission paths when there are two or more available transmission paths; a transmission path having a minimum expected transmission value among the transmission paths is set as an actual transmission path of the packet; the expected transmission value is a sum of expected transmission counts, the expected transmission count being a reciprocal of multiplication of forward transmission success rate and backward transmission success rate of a communication link between the nodes disposed on the transmission paths—the node means the sender, the receiver, or the access point—; and when a signal to interference plus noise ratio (SINR) value of the communication link in which a first access point transmits is equal to or more than a predetermined capture threshold if a second access point transmits concurrently with the first access point among the nodes disposed on the transmission paths, the second access point determines that the packet can be concurrently transmitted, and the expected transmitted count for the communication link in which the second access point transmits is multiplied by a constant smaller than 1 to calculate the expected transmission value.
[0014] Other features and aspects will be apparent from the following detailed description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIGS. 1A and 1B are diagrams showing transmission schedules of PHY capture and MIM capture, respectively;
[0016] FIG. 2 is a diagram showing an operation of a WLAN system according to an exemplary embodiment of the present invention;
[0017] FIG. 3 is a flowchart showing an opportunistic concurrent transmission method from a viewpoint of one AP according to an exemplary embodiment of the present invention;
[0018] FIGS. 4A and 4B are diagrams showing frame schedules in a case of concurrent transmission and in an opposite case of non-concurrent transmission method according to the exemplary embodiment of the present invention, respectively;
[0019] FIG. 5 is a schematic diagram illustrating an example of a wireless mesh network in order to explain a process of calculating an EXT value for routing for a wireless mesh network; and
[0020] FIG. 6 is a diagram illustrating an example of a wireless mesh network system using a routing method according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0021] Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. Throughout the drawings and the detailed description, unless otherwise described, the same drawing reference numerals will be understood to refer to the same elements, features, and structures. The relative size and depiction of these elements may be exaggerated for clarity, illustration, and convenience. The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. Accordingly, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be suggested to those of ordinary skill in the art. Also, descriptions of well-known functions and constructions may be omitted for increased clarity and conciseness.
[0022] FIG. 2 is a diagram showing a WLAN system to which an opportunistic concurrent transmission method is applied according to an exemplary embodiment of the present invention.
[0023] As shown in FIG. 2 , the WLAN system according to the exemplary embodiment of the present invention includes a central controller 210 , two access points (APs) AP 1 ; 221 and AP 2 ; 222 , and client devices R 1 ; 231 , R 2 ; 232 , and R 3 ; 233 connected to each AP, respectively. Both APs are located within the transmission range of each other. Though two APs and three client devices are shown in FIG. 2 for better comprehension and ease of description, the numbers of APs and the client devices are not necessarily limited thereto.
[0024] In the figure, solid arrows mean a transmission link between an AP and a client device, and dashed lines denote interferences among concurrent transmissions. The value in a box indicates received SINR when packets are transmitted concurrently. That is, the clients R 1 and R 2 are associated with AP 1 and a signal transmitted from AP 2 becomes an interference signal for R 1 and R 2 . On the contrary, the client R 3 is associated with AP 2 and, as a result, a signal transmitted from AP 1 becomes the interference signal for R 3 . When concurrent transmission is made from AP 1 and AP 2 , R 1 , R 2 , and R 3 receive signals having SINRs of 1 dB, 5 dB, and 13 dB, respectively.
[0025] AP 1 and AP 2 may transmit concurrently by referring to an interference map. The interference map is a table of relative signal strength of each transmission depending on the transmission orders. In the exemplary embodiment shown in FIG. 1 , the central controller 210 makes interference map from the individual report of each AP and distributes it to all APs. However, there are lots of schemes that make an interference map without a central controller.
[0026] Hereinafter, an opportunistic concurrent transmission method according to the exemplary embodiment of the present invention will be described referring to FIG. 2 . It is assumed that each of AP 1 and AP 2 has packets to transmit to its associated clients R 1 and R 3 , respectively.
[0027] Let AP 1 transmit a packet to R 1 first, and AP 2 transmit a packet to R 3 after the preamble time of the AP 1 's packet. AP 1 's transmission may result in a collision and cannot be decoded successfully by R 1 since the SINR value (1 dB) of the received signal does not satisfy the capture threshold (4 dB). Of course, AP 2 's transmission may succeed due to a higher SINR value of 13 dB.
[0028] Now, let us change the transmission link. If AP 1 transmits a packet to R 2 not to R 1 , then a following concurrent transmission of AP 2 may not corrupt the AP 1 's packet. The reason is that SINR value of R 2 (5 dB) is higher than the capture threshold (4 dB).
[0029] Consequently, AP 2 has an opportunity to transmit a packet concurrently with AP 1 when AP 1 send a packet to R 2 . AP 2 can overhear the transmission of AP 1 and knows which link is used in this transmission by sniffing the MAC header of the ongoing packet. Referring the interference map, AP 2 knows that its concurrent transmission will not destroy the ongoing transmission of AP 1 . That is, AP 2 assures its concurrent transmission satisfy the required SINR thresholds for capturing both packets.
[0030] When it is determined that the concurrent transmission will cause a problem, that is, when it is determined that the transmission of another AP will fail by the concurrent transmission, the AP defers its own transmission as a standard DCF operation.
[0031] FIG. 3 is a flowchart showing an opportunistic concurrent transmission method from a viewpoint of one AP according to an exemplary embodiment of the present invention.
[0032] First, an AP determines whether there are packets to be transmitted (S 310 ). If so, the AP overhears transmission from another AP to acquire information on a transmission link (S 320 ). Next, AP finds out the SINR value for the transmission link by referring to the interference map (S 330 ). If the SINR value is equal to or higher than the capture threshold (S 340 ), the AP transmits its packets concurrently (S 350 ). If the SINR value is lower than the capture threshold (S 340 ), the AP enters the back off period (S 360 ) and waits for the transmission to be completed. When the transmission in completed (S 370 ), the AP transmits its own packets (S 380 ).
[0033] FIGS. 4A and 4B shows timings of the opportunistic concurrent transmission and non-concurrent transmission, respectively.
[0034] FIG. 4A shows the case of concurrent transmission. While AP 1 is transmitting a frame, AP 2 determines whether concurrent transmission can be made through a MAC header of the frame being transmitted by AP 1 and the interference map. If AP 2 determines to transmit concurrently, AP 2 transmits its own frame right away.
[0035] On the contrary, FIG. 4B shows the case in which it is determined that concurrent transmission is not made. When AP 2 overhears the transmission of AP 1 and determines that concurrent transmission is not made, AP 2 waits until the transmission of AP 1 is completed and transmits its own frame later.
[0036] Meanwhile, as described above, the opportunistic concurrent transmission according to the exemplary embodiment of the present invention can operate according to the above described method in a broadcast environment without an ACK frame, but requires a more complicated schedule when an ACK frame is used for receipt notification in a unicast environment. Still, the frame scheduling may also be performed with reference to the MAC header. Since the AP may get to know the transmission time of the ACK frame by referring the MAC header of the transmitting packet from another AP, the AP can schedule the transmission of its own packet not to be overlapped with the ACK frame of the transmitting packet from another AP.
[0037] According to the exemplary embodiment of the present invention, the concurrent transmission method as described above is used for routing for the wireless mesh network.
[0038] Each node between a sender and a receiver in the wireless mesh network transfers a packet received via one or more hop to a neighboring node within the range of a wireless transmission. In this case, a path capable of transferring the packet between the sender and the receiver may be in plural and a throughput of the entire network varies according to the path in which the packet is taking. Thus, it is important to choose an efficient path of packet transmission. An expected transmission count (ETX) value is used for routing. The ETX is disclosed in Couto DSJD et al., A high throughput path metric for multi-hop wireless routing, Mobicom03.
[0039] Hereinafter, a process of calculating the ETX value for routing in the wireless mesh network will be described with reference to FIG. 5 . FIG. 5 is a schematic example of the wireless mesh network in order to describe the calculation of the ETX value. In FIG. 5 , S represents a sender, R represents a receiver, and AP 1 , AP 2 , AP 3 , and AP 4 represents access points. A connection line connecting each node (the sender, receiver, and access points) is a communication link and a number marked on each communication link means transmission success rate for each communication link. For ease of description, it is assumed that forward transmission success rate and backward transmission success rate are the same as each other.
[0040] The ETX is a method of calculating a path targeting the wireless mesh network, and an expected value for how many times the transmission is performed for successful transmission is calculated with respect to each communication link. The ETX for one link is defined as the following Equation 1.
[0000]
ETX
=
1
d
f
×
d
r
[
Equation
1
]
[0041] Herein, df means transmission success rate for a forward direction, and dr means transmission success rate for a backward direction. For example, as shown in FIG. 5 , since the transmission success rate is 0.9 (forward and backward) in the communication link between the sender S and the AP 1 , the ETX becomes 1/(0.9*0.9)=1.234.
[0042] A sum of the ETXs for each link included in the path is a cost for the entire path and it is represented by the following Equation 2.
[0000]
PATH
Cost
=
∑
i
=
1
n
ETX
[
Equation
2
]
[0043] As shown in FIG. 5 , there are two different paths between the sender S and the receiver R. A first path PATH 1 is S->AP 1 ->AP 2 ->R and a second path PATH 2 is S->AP 3 ->AP 4 ->R. ETX values for two paths are calculated as the following Equation 3 and Equation 4, respectively. In this case, a respective ETX value for each communication link may be calculated by each node and the sender may acquire the entire ETX value by combining the calculated result.
[0000]
PATH
1
:
Σ
ETX
=
1
0.9
×
0.9
+
1
1
×
1
+
1
1
×
1
≈
3.234
[
Equation
3
]
PATH
2
:
Σ
ETX
=
1
1
×
1
+
1
1
×
1
+
1
1
×
1
=
3
[
Equation
4
]
[0044] According to the results calculated by Equation 3 and Equation 4, the sender S determines the PATH 2 , which has a smaller ETX value, as a better path and selects the PATH 2 .
[0045] However, a different result may come out considering concurrent transmission.
[0046] FIG. 6 shows an example of a wireless mesh network system using a routing method according to an exemplary embodiment of the present invention.
[0047] In FIG. 6 , it is assumed that the AP 2 can perform the concurrent transmission using an MIM function during the transmission from the AP 1 under the same condition. In this case, the ETX value can be reduced with respect to a link capable of MIM, and, for example, the ETX value may be reduced by half. Accordingly, a transmission expected value of each path changes. This is represented by the following Equation 5 and Equation 6, and since the ETX value is calculated by considering the MIM concurrent transmission, the expected value is represented by ETX+MIM. Even in this case, considering the concurrent transmission, an ETX+MIM value for each communication link may be calculated by each node and the sender may acquire the entire ETX+MIM value by combining the calculated result.
[0000]
PATH
1
:
Σ
(
ETX
+
MIM
)
=
1
0.9
×
0.9
+
1
1
×
1
+
1
1
×
1
×
1
2
≈
2.834
[
Equation
5
]
PATH
2
:
Σ
(
ETX
+
MIM
)
=
1
1
×
1
+
1
1
×
1
+
1
1
×
1
=
3
[
Equation
6
]
[0048] As described above, if the ETX value is calculated taking the concurrent transmission into consideration, as shown in Equation 5 and Equation 6, the sender S determines the PATH 1 as a better routing path and selects the PATH 1 , such that a transmission throughput of the entire system increases.
[0049] A number of exemplary embodiments have been described above. Nevertheless, it will be understood that various modifications may be made. For example, suitable results may be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Accordingly, other implementations are within the scope of the following claims. | In the wireless mesh network including a sender, a receiver, and a plurality of access points disposed between the sender and the receiver, available transmission paths between the sender and the receiver are determined; transmission expected values are calculated for the transmission paths; and a transmission path having a minimum transmission expected value is set as an actual transmission path. The transmission expected value is a sum of expected transmission counts, which is a reciprocal of multiplication of forward transmission success rate and backward transmission success rate of a communication link between the nodes disposed on the transmission paths. When an access point can transmit a packet concurrently with another access point, the expected transmitted count is reduced by half. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of U.S. patent application Ser. No. 09/641,031, entitled Dynamic Index and Search Engine Server, to the present Applicants, filed on Aug. 16, 2000, and that application claimed the benefit of the filing of U.S. Provisional Patent Application Ser. No. 60/149,322, entitled Dynamic Index and Search Engine Server, filed on Aug. 16, 1999, and the specifications thereof are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention (Technical Field)
The present invention relates to Internet search indexes and engines.
2. Background Art
There are millions of World Wide Web (“web”) sites on the Internet today, and so it is becoming increasingly difficult to index the available information quickly so that an individual can easily find the current and complete information (web sites) in which they have interest. Many search engines and search indexes on the web (hereafter web indexes) are simply too large to be useful. Sifting through the thousands of web sites that come from a single search or under a single topic (in an index) is often cumbersome and unfruitful.
The problem is two-fold. First, search indexes are very broad. Most people are not interested in every topic on the web; instead they are only interested in a small portion of the many topics that exist. Web users would like to have a web index that only encompasses their topics or subtopics of interest. But creating a customized web index is very time consuming and can be very expensive. Therefore, most people wade through many, many other topics to get to the few topics in which they have interest.
The second problem is with search engines on the web. The web is typically searched by keyword searches of the entire sampling of the web that has been indexed by any given search engine. These searches usually bring up a very large number of sites that have nothing to do with what the user intends to find. For example, someone searching for the poems of Robert Frost may simply type in the poet's name. The result, however, is often unproductive because most search engines can only search for the exact word or words and cannot put the word into context. Therefore the search results for “frost” may include the word “frost” in the wrong context such as in gardening tips. Another example is that a search for web sites about basketball courts may result in the word “court” being taken out of context and the searcher gets not only basketball courts (and other types of sports courts), but also get the supreme court, the court of appeals, etc.
The present invention provides a solution to the problems noted above by permitting individuals to create and organize search indexes specific to their needs.
SUMMARY OF THE INVENTION
Disclosure of the Invention
The present invention comprises an apparatus for, computers software for, and method of providing personalized search capabilities of hypertext transmission protocol pages comprising: providing an index server maintaining an index to hypertext transmission protocol pages and employing a hierarchical plurality of topic categories; permitting a user to specify any subset of the plurality of topic categories; and adding to a hypertext transmission protocol page controlled by the user link information permitting execution of searches of the index server in any category of the subset but only of categories in the subset. In the preferred embodiment, the user is permitted to propose addition of a hypertext transmission protocol page to the index server in conjunction with one or more categories of the subset, which causes automatic addition of the proposed page to the index server wherein the user can search the proposed page via the link information and wherein initially other users will not search the proposed page even if searching the proposed one or more categories. This preferably involves first verifying that a uniform resource locator address for the proposed page is valid and that the proposed page is not already indexed under the proposed one or more categories, as well as subsequently allowing other users to search the proposed page when searching one or more of the proposed one or more categories once suitable checks have been performed. The user can rename one or more categories of the subset as it will appear on the hypertext transmission protocol page controlled by the user, can rearrange hierarchicalization of one or more categories of the subset as it will appear on the hypertext transmission protocol page controlled by the user, and can within a branch of a hierarchy of categories either include or exclude subcategories in the branch, or both. The subset selection can be reexecuted by the user at any time, whereby the link information is dynamically updated to correspond to a new subset.
Other objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated into and form a part of the specification, illustrate several embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating a preferred embodiment of the invention and are not to be construed as limiting the invention. In the drawings:
FIG. 1 is a general block diagram of the preferred method and apparatus of the invention.
FIG. 2 is a block diagram of the preferred method and apparatus of the customization of web indexes.
FIG. 3 is a block diagram of the preferred method and apparatus of the system to add and filter links.
FIG. 4 is a block diagram of a general web index.
FIG. 5 is a more specific block diagram of the preferred method and apparatus of viewing a general web index.
FIG. 6 is a block diagram of an example of changing the topical hierarchy.
FIG. 7 is a block diagram of the preferred method and apparatus for excluding and setting up topics to customize.
FIG. 8 is a block diagram illustrating the results of the operation of FIG. 7 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Best Modes for Carrying Out the Invention
The present invention is of a server method and apparatus to allow anyone to put a web index on their web site without having to update, store, check or catalogue any of the link information themselves, yet still allowing them to add web sites to the index. The web site owner can customize several aspects of the look and feel of the web index, then choose a subset of the topics available or choose all topics.
Take as an example a young girl maintaining a personal web site. The present invention allows her or her parents to set up a customized index on her web site. She might choose to have her topics be:
Barbie® and Friends Toys Games
With the present invention, when she browses using her web site she does not have to wade through other topics to get to her three topics of choice. Furthermore, because the present invention will exclude all other topics from her customized web index, a search of her index will provide her a more useable set of results—only on her topics. She can search for the words “Barbie” or “Ken,” and because the search would only be on the web sites included in her particular topics, she would get very meaningful results.
The web site owner can also arrange the topics in a personalized hierarchy or keep the default hierarchy. For example, if someone included a Sports topic on their web index, they could arrange the links within Sports and even change the name of the topics. As just one example, they could take a sports topic with subtopics of Baseball, Basketball, Cheerleading, Cricket, Curling, Field Hockey, Football, Hockey, Lacrosse and Polo as follows:
Sports
Baseball Basketball Cheerleading Cricket Curling Field Hockey Football Hockey Lacrosse Polo
and rearrange it to make some of the subtopics main links on the resulting customized web index, such as follows:
Baseball Basketball—The Best Sport!! Hockey Football Other Sports
Cheerleading Cricket Curling Field Hockey Lacrosse Polo Rugby
This example illustrates that not only can the web site owner change the hierarchy, but also change the names of the subtopics, making a truly unique web index. This is just one example of how the hierarchy and topic names could be changed. The possibilities are, as is readily understood, endless.
In order to obtain a customized web index for their web site, a web site owner would connect to the Dynamic Index and Search Engine Server (“DISE Server”) of the invention to set up their custom index. This would preferably include:
Setting the look and feel of the web index Choosing the topics to be included Rearranging topics (changing hierarchy) Adding new topics Renaming existing topics
After the web site owner has customized the DISE Server for their web site, they are provided a unique DISE Server Connector (“DSC”) to place on their web site. The DSC is a gateway to the DISE Server that connects the web site to the DISE Server so that when someone accesses a web page containing the DSC, the DISE Server is accessed and the customized information is included on the web page.
A very important part of this invention is that the web index is dynamically included on the web page. Therefore, the DISE Server is able to update, store, check and catalogue the link information and any changes are instantaneously seen on the web indexes. In this way the web site owner does not have to update his links; he does not have to make sure they are still valid. The DISE Server handles all the work for him. However, the web site owner can add links to his web index.
Everyone with a DISE Server customized web index on their web site will be able to request to add links to their web index. This request will include information about the link as well as the suggested topic in which to include the link. When the DISE Server receives the request, it puts the request through a series of filters to determine if the link is valid. If a link is deemed valid, it is added to the requester's web page. The link request is then sent through a second filtering process to see if it should be added to the global DISE Server index. If this second filtering process determines that the link should be added to the global index (DISE Server), the link will be added and, therefore, will automatically be added to all web indexes that contain the topic.
In this manner the web site owner is spared the expense and time it takes to maintain a web index while still being able to dynamically add links to their web index.
Furthermore, by allowing all web site owners to add to the global index, each topic will be more complete. The web site owners can update the topics of interest to them, as they use their own customized index, and every other user will benefit by having the global information in each topic updated much faster and more efficiently.
The present invention allows for an unlimited number of new, yet completely distinct, indexes, which can be created by any number of individuals, companies, groups and organizations. In other words, this technology enables any individual, company or organization to put up their own web index—each with its own look, feel, and method of organizing and prioritizing links. Furthermore, when someone does a keyword search on a web site with a DISE Server customized web index, they are only searching the subset of web sites that are included in this particular web index, and not the entire web. This creates much more relevant search results.
It is important to note that this invention works with any search technology available at this time or invented in the future. It is not particularly relevant to the invention how web sites are searched, but rather that only the customized subset is searched.
A generalized networked computer system consistent with the present invention is shown in FIG. 1 . Web page servers ( 22 ) are attached to the Internet ( 26 ). These servers contain web pages that will be linked from a web index as well as web pages that will utilize the DISE Server to have dynamic web indexes. User computer systems ( 24 ) capable of executing a Web browser are coupled logically through a network ( 26 ), such as the internet, to any number of web page servers ( 22 ).
The present invention preferably encompasses any number of logical and physical computer systems ( 12 ) with access to one or more individual databases ( 14 ), a database management system ( 14 ), a system to implement the customization ( 18 ), a system to add and filter links ( 16 ), and a system to serve the web indexes dynamically ( 20 ). The present invention includes a global index of web pages and one or more methods of searching those web pages. The present invention also includes a default topic structure or hierarchy to contain the global index. Each topic will contain one or more subtopics and one or more links to external, relevant web pages (hereafter external links) under that topic.
When an individual or company (web site owner) chooses to use the DISE Server to incorporate a web index on their web site, they must first set up their customization. FIG. 2 is a generalized flowchart of the process of customizing an individual web index. In the preferred embodiment, the web site owner ( 27 ) must set up a unique account in order to store and retrieve the web site owner's web index setup. If he has not yet set up an account ( 28 ), he will need to go through the process to obtain a unique identifier ( 30 ). He can then login ( 32 ) and customize many aspects of the look and feel ( 34 ), including, but not limited to fonts (size, color, link color, visited link color, etc.), number of columns on the home page and on subsequent pages, whether subtopics will appear on the home page, etc. The web site owner can then completely customize the topic, including the hierarchy and the topic names ( 36 ).
FIGS. 4-7 illustrate the customization of a web index. FIG. 4 is a general block diagram of a possible web index. There is a main page or home page ( 74 ) with link to topics ( 76 , 78 , 80 , 82 , 84 , 86 , 88 and 90 ). These subtopics in turn have their own subtopics. One such set of sub-subtopics is shown in FIG. 4 ( 92 , 94 , 96 , 98 , 100 ).
FIG. 5 shows an example of how the web site owner might browse through the topics. In the preferred embodiment the web site owner is able to customize the topics by manipulating folders, as on computer, that represent the topics and subtopics. In this example the sports topic ( 106 ) is clicked on to reveal its subtopics ( 110 ). Under the sports topic there are many other subtopics including basketball ( 116 ). Under Basketball there are several subtopics, including NBA ( 118 ). When NBA is clicked on, it is seen that there are also subtopics under NBA ( 120 ).
To customize his web index, the web site owner will be able to move any subtopic to a different level or under a different topic. FIG. 6 shows how a subtopic might be clicked and dragged to a new topic. This is very much the same way file and folders are typically moved around on computers today. Specifically, in this example the “Chicago Bulls” subtopic ( 126 ) is moved above its current parent topic of basketball directly into the Sports topic ( 128 ), so that the topic “Chicago Bulls” is now a subtopic of Sports ( 130 ).
To specify topics that the web user does not want included, he can simply mark them to be taken off. FIG. 7 illustrates this feature of the invention. The subtopics that are not to be included are simply “turned off” ( 78 , 80 , 82 , 84 , 86 , 88 , 100 ). FIG. 8 shows how this appears to the user in the preferred embodiment. The topics that turned off are “ghosted.” In other words, the folder representing those topics is changed to a different, much lighter color ( 135 ). To further show the customization of the topical hierarchy, FIG. 8 shows how the “Baseball” subtopic might be moved from “Sports” to be a top-level topic ( 135 , 140 ). FIG. 8 then shows how the hierarchy might look to the user ( 150 ). In this example, the main topics are Baseball ( 92 ), Sports ( 90 ) (including subtopic Chicago Bulls ( 142 )), and Business ( 76 ). Other customization of the topics can also be performed, including changing the name of any topic and creating new topics.
In the preferred embodiment, the external links that fall under any topic will stay under that topic at all times, whether the topic is moved or renamed, although provision for the external links to be moved under different topics certainly falls within the scope of the invention.
After the web site owner has customized the topics, his preferences are stored. In the preferred embodiment, the preferences are stored in a database, although any reasonable storage method would fall within the scope of the invention.
The present invention then generates the unique DISE server connector (“DSC”) for the web site owner ( 38 ). The DSC is source code that is placed on the web site ( 40 ) to add the dynamic index to the site. This DSC source code could be implemented in HTML, XML, SGML, Java, ASP, or any other feasible source code options for web sites. The preferred embodiment has many types of DSC source code options to accommodate the many web site hosting environments available now or in the future.
Individuals and companies host their web sites on one or more web servers. These web servers store the individual web pages that make up the web sites along with any number of programs, database, etc., which encompass the web site. Since web servers vary so widely, and the technology is constantly changing, it is difficult to choose one particular implementation. The key to the DSC is that it will connect to the present invention over the Internet and dynamically include language that represents the dynamic index.
In the preferred embodiment, when the index is placed on the web page some other information and features appear on the page as well (herein called other information). This other information preferably includes:
1. Banner advertisements or other advertisements;
2. A way to add new links;
3. A copyright statement;
4. An ownership statement;
5. Links to a web page containing information about the present invention;
6. A search box enabling a search of the customized index or the entire web; and
7. A way to reconfigure the web index.
In the preferred embodiment, the banner advertisements are optional, but there are preferably other mandatory information that must be included with the web index.
Once the web site owner places the DSC on his web page, the code will be activated when any web browser views the web page. When a web user ( 24 ) views the web page, the unique customized web index and other information for that web page will appear on the web page dynamically ( 41 ).
At any time the web site owner can reconfigure his settings of the present invention, allowing him to change his customized web index. In the preferred embodiment, a new DSC is not be required for every reconfiguration, although requiring that the DSC be changed after each reconfiguration is within the scope of the present invention.
In the preferred embodiment, anyone who uses any of the customized web indexes can suggest links to be added to the web index. These suggestions include the suggested link, the suggested title of the link the suggested link description and the topic in which to include the link. FIG. 3 shows a generalized block diagram of user-added links to the system. Before one of the “at-large” link requests ( 42 ) are incorporated into the global index, the link suggestions are preferably filtered through two filtering processes: 1) a filtering process to determine whether the link is valid ( 46 ); and 2) a filtering process to determine whether the link should be added to the global index ( 54 ).
The first filtering process, to test whether the link is valid ( 46 ), preferably includes, but is not necessarily limited to:
1. Checking if the link is a valid web page;
2. Making sure that the same link has not already been added to the specified topic; and
3. Checking that the title of the link of words used to describe the link meet certain criteria (e.g., no profanity, etc.)
The second filtering process to determine whether the link should be added to the global index ( 54 ) preferably includes, but is not necessarily limited to:
1. Checking to make sure that the suggested link is appropriate for the topic;
2. Checking to make sure that the proposed description and title of the link are appropriate; and
3. Checking to make sure that the proposed description and title of the link are descriptive of the contents of the link.
However, the web site owner who has included a customized web index on his web site will have more choices. He can add a link to his index dynamically. If the web site owner suggests a link ( 44 ), his request is only put through the first filtering process to test that the link is valid ( 46 ) before it is included on his web site. If the link is deemed valid then the link is added to the requester's web index ( 52 ). In the preferred embodiment the filtering process is done electronically so that the link will be added to the requesting web site owner's web site immediately.
Furthermore, every link suggestion posted by a web site owner is preferably also being sent through the second filtering process to determine whether the link should be added to the global index ( 54 ). In this manner, as each individual updates his or her web index, the global web index is updated ( 56 ) as well allowing for a much more complete index than could otherwise be accomplished.
It is important to note that under the present invention it is also possible for the web site owner to exclude individual links from his web page. This feature is not included in the preferred embodiment because of the complexity of keeping track of whether one link should be included in any number of web sites.
A novel and additional feature of the invention is that the customized index can be employed as an inclusion filter for web content. Many people use filters on the Internet to disallow browsing of inappropriate web sites. Many people and businesses use filters so that no one can browse pornography or other web sites deemed inappropriate. With the present invention, a user can set up their customized web index and then employ that index as an inclusion filter set into place so that the user can only browse web sites that are included in the index. A good example of this is a filter for use by a child. Many web filters exist for children and, in fact, many of the largest Internet Service Providers (ISPs) have child filters. But if a user uses one of these established child filters then they are letting someone else decide which web sites are appropriate for their children. Instead, with the present invention, the parent can use the invention to customize a web index, excluding all the topics that they deem inappropriate for their children, and then use it as an inclusion filter. The children would then only be able to view web pages that were included in the topics of the index customized by the parent.
Although the invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above are hereby incorporated by reference. | An apparatus for, computers software for, and method of providing personalized search capabilities of hypertext transmission protocol pages comprising: providing an index server maintaining a dynamic index to hypertext transmission protocol pages and employing a tree-structured hierarchical plurality of topic categories; permitting a user to specify any subset of the plurality of topic categories; and adding to an electronic medium controlled by the user link information permitting execution of searches of the index server in any category of the subset but only of categories in the subset. | 6 |
BACKGROUND OF THE INVENTION
This invention relates generally to an engine control system for a marine propulsion device, and particularly to an engine control system which is adapted to protect a two-cycle outboard motor.
With two-cycle internal combustion engines, it has been the general practice to lubricate the engine by mixing lubricating oil with the fuel mixture. Although such arrangements offer extreme simplicity, the mixing of lubricating oil with the fuel can be troublesome to the user of the engine. In addition, the requirement for mixing lubricant with the fuel and lubricating the components of the engine with the fuel/air mixture does not always insure the adequate amount of lubrication to the various components to be lubricated under all running conditions. In order to obviate some of these difficulties, it has been proposed to provide a lubricating system where the lubricant is contained within a separate tank from the fuel and is supplied to the engine during its running. Such arrangements have a number of advantages. One such separate lubrication system is described in the commonly assigned co-pending U.S. patent application Ser. No. 610,847, entitled "Separate Lubricating System For Marine Propulsion Device", which is hereby incorporated by reference.
When the engine in question constitutes the power unit of an outboard motor, however, the provision of such separate lubricating systems can give rise to certain practical difficulties. For example, when the lubricant in the storage tank or reservoir reaches a low level, it is desirable to run the outboard motor at a low speed which will conserve the supply of the lubricant and prevent the engine from running at a high speed when the supply of lubricant is depleted. Thus, it would be desirable to provide a protection system for the engine which will regulate the speed of the engine so as to reduce the engine speed to a predetermined low level. Such a protection system would override the particular engine throttle setting which may be set for a higher engine speed. It would also be desirable for the protection system to provide a perceptible output which would indicate to the operator that the lubricant in the storage tank should be replenished. However, since many marine propulsion devices have throttles which can be set in a fixed position without being operated by hand, it is important for the protection system to avoid any unintentional increase in engine speed which could result as the lubricant storage tank is being replenished.
It is, therefore, a principal object of this invention to provide an improved engine control system which will protect a two-cycle outboard motor.
It is another object of this invention to provide a protection system for an internal combustion engine which is capable of controlling an operating parameter of the engine in response to a predetermined condition until such time as this control is intentionally terminated.
It is a more specific object of the present invention to provide a protection system for an internal combustion engine which will control the speed of the engine so as to cause a reduction in the engine speed when the lubricant in the storage tank reaches a predetermined level, and maintain the engine speed at a predetermined low level until such time as this control is intentionally terminated.
It is a further object of this invention to provide a protection system which is also capable of controlling the speed of the engine so as to reduce the engine speed in response to an overheat condition.
It is an additional object of this invention to provide a protection system for an internal combustion system which is also capable of providing a plurality of perceptible outputs indicative of the lubricant level and the presence/absence of an overheat condition.
It is yet another object of this invention to provide a protection system for an outboard motor which will maintain an engine control function in response to a low lubricant level, even after the lubricant supply is replenished, until such time as this control is positively disengaged by the operator.
It is yet a further object of this invention to provide a protection system for an internal combustion engine which may be readily and inexpensively interfaced to a capacitive discharge ignition system of the engine to automatically initiate control of the speed and manually release such control over the engine speed.
SUMMARY OF THE INVENTION
To achieve the foregoing objects, the present invention provides a control system for an internal combustion engine which generally comprises means for detecting a predetermined condition, means for controlling a predetermined operating parameter of the engine in response to the detection of this predetermined condition, means for manually terminating this control, and means for maintaining this control after the predetermined condition has ceased until this control is manually terminated. In accordance with one feature of the present invention, the predetermined condition is a low lubricant level condition. In accordance with another feature of the present invention, the predetermined operating parameter is the speed of the engine which is gradually reduced to a predetermined low level.
In accordance with a further feature of the present invention, the control system includes means for producing perceptible outputs which are indicative of both the presence of the low lubricant level condition and the approach of this condition.
In accordance with yet another feature of the present invention, the control system includes means for sensing an engine overheat condition, and means for reducing the speed of the engine in response to the detection of the overheat condition.
Additional advantages and features of the present invention will become apparent from a reading of the detailed description of the preferred embodiments which makes reference to the following set of drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic electrical diagram showing a first embodiment of an engine ignition and speed control system according to the present invention.
FIG. 2 is a schematic electrical diagram showing a second embodiment of an engine ignition and speed control system according to the present invention.
FIG. 3 is a diagrammatic representation explaining the operation of the embodiment of FIG. 2.
FIGS. 4 and 5 are schematic electrical diagrams showing further embodiments according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a schematic diagram of a protection system 10 is shown to be connected to a capacitive discharge ignition system 12 of an internal combustion engine 14 according to the present invention. As will be appreciated from the description below, the protection system 10 is capable of selectively interrupting the operation of the ignition circuit 12, and thereby control the speed of the engine 14. The ignition circuit 12 includes a charging coil 16, rectifying diodes 18 and 20, a silicon controlled rectifier (SCR) 22, a capacitor 24, a pulser coil 26, and an ignition coil 28. The secondary winding of the ignition coil 28 is connected to a spark plug 30 of the engine 14.
Under normal engine running conditions, the charging coil 16 will charge the capacitor 24 in the polarity shown, and the capacitor 24 will remain charged until the pulser coil 26 generates a trigger signal sufficient to gate on the SCR 22. When the SCR 22 is gated on and rendered conductive, the capacitor 24 will rapidly discharge through the primary winding of the ignition coil 28. This rapid discharge will produce a sufficiently high voltage potential in the secondary winding of the ignition coil 28 to cause the spark plug 30 to spark and ignite the fuel mixture in the combustion chamber of the engine 14.
The protection system 10 includes a lubricant level detector switch 42 which is suitably mounted in a lubricant (e.g. oil) storage tank or reservoir 34. The lubricant level detector switch 32 includes a float arm 36 which is adapted to pivot in response to the lubricant level in the tank 34. The lubricant level detector switch 32 includes a first set of switch contacts 38a and 38b and a second set of switch contacts 40a and 40b. In the embodiment shown in FIG. 1, switch contacts 38a and 40a are normally open, while switch contacts 38b and 40b are normally closed.
When the lubricant level in the tank 34 is high, the float arm 36 of the lubricant level detector switch 32 will articulate to close switch contact 38a and open switch contact 38b. When the lubricant level in the tank 34 reaches a predetermined low level, the pivoting of the float arm 36 will close the switch contact 40a and open the switch contact 40b. In a lubricant level range between the high and predetermined low lubricant levels, the switch contacts 38a and 40a will be their normally open positions, and the switch contacts 38b and 40b will be in their normally closed position. The predetermined low lubricant level generally represents a lubricant level at which it is undesirable to maintain the engine 14 running at a high speed. Thus, it is desirable when the predetermined low lubricant level is reached for the operator to replenish the lubricant supply in the tank 34.
The protection system 10 includes a power supply which may be, for example, a battery 42, and means for recharging the battery, such as a generating coil 44 and a diode bridge rectifier 46 connected across the terminals of the battery. The generating oil may conveniently form part of a magneto generator assembly with the charge oil 16 and the pulser coil 26. The protection system 10 also includes a main switch 48 which in the embodiment shown is connected generally to one end of the battery 42 The main switch 48 controls the supply of electrical power to the circuitry of the protection system. However, it should be understood that the particular placement of the main switch 48 in the protection system circuit shown in FIG. 1 is intended to be exemplary only, and that other suitable placements for the main switch may be provided in other suitable applications for the present invention.
The circuitry for the protection system 10 includes a green lamp 50, a yellow cautionary lamp 52, and a red warning lamp 54 which are each connected in separate parallel legs of the protection system circuit. These parallel circuit legs are in turn generally connected across the battery 42 when the main switch 48 is in a closed position.
The switch contact 38a is connected in series with the green lamp 50, so that when the lubricant level in the tank 34 is high and the switch contact 38a is closed, then the green lamp will turn on from the power supplied by the battery 42. The green lamp 50 provides a visually perceptible output which will indicate to the operator that the lubricant level in the tank 34 is generally high. It should be appreciated that when both the main switch 48 and the switch contact 38a are closed, a series circuit loop is provided by the battery 42, the main switch 48, the switch contact 38a, and the green lamp 50.
The yellow cautionary lamp 52 is connected electrically in series with both the switch contacts 38b and 40b. Accordingly, when both the switch contacts 38b and 40b are closed, the yellow cautionary lamp 52 will turn on, and indicate to the operator that while there is still a sufficient supply of lubricant in the tank 34, the lubricant supply will need to be replenished within a reasonable time to maintain a high operating speed for the engine 14. Therefore, the yellow cautionary lamp 52 indicates the approach of a low lubricant level condition. It should be appreciated that when the switch contact 38b closes, the switch contact 38a will be opened and the green lamp will be turned off. Similarly, when the switch contact 38b is closed, the switch contact 40a will be open and the red warning lamp 54 will remain off.
The red warning lamp 54 is connected in series with a self-holding circuit generally designated by the reference numeral 56. The self-holding circuit 56 includes an SCR 58, a capacitor 60 connected across the gate and cathode of the SCR, and a resistor 62 connected between the gate of the SCR and the switch contact 40a. When the switch contact 40a closes at the point where the predetermined low lubricant level has been reached, the SCR will be gated on through the resistor 62 to light the red warning lamp 54. It should be noted that the capacitor 60 and the resistor 62 combine to cause a short delay between the time at which the switch contact 40a closes and the time in which the SCR 58 is turned on or rendered conductive. The red warning lamp 54 provides a visually perceptible output to the operator which will indicate that the lubricant in the tank 34 must be replenished.
When the SCR 58 conducts, a speed reduction signal is sent by an "OR" gate 64 to a switch 66 which will close in response to this signal. The switch 66 is connected to an override circuit portion of the protectioon system 10 which interconnects the pulser coil 26 with the gate of the SCR 22. This circuitry includes a diode 68 connected across the pulser coil 26, a diode 70 connected between one end of the pulser coil 26 and the gate of the SCR 22, resistors 72 and 74, a capacitor 76, and a transistor 78. The resistor 72 and the capacitor 76 are connected in series across the gate of the SCR 22 and ground. The base of the transistor 78 is connected at a circuit junction 80 between the resistor 72 and the capacitor 76, the collector terminal of the transistor is connected to one side of the switch 66, and the emitter of the transistor is connected to ground. The other end of the switch 66 is connected to the gate of the SCR 22. The resistor 74 is connected across the capacitor 76 with one end being connected to the circuit junction 80.
When the switch 66 is closed by the speed reduction signal, the transistor 78 will be permitted to conduct when the base terminal of the transistor reaches the threshold level of the transistor. With the engine 14 rotating at a high speed, trigger signals from the pulser coil 26 will charge the capacitor 76 to a sufficient potential that the transistor will turn on. This will create a shunt path to ground for the trigger signals from the pulser coil 26 through the transistor 78 which will prevent the pulse signals from gating on the SCR 22. Accordingly, during this time, the capacitor 26 in the ignition circuit 12 will be prevented from discharging and the engine 14 will misfire. Such misfiring will cause the speed of the engine 14 to gradually decrease to a predetermined point which is controlled by the respective component values for the resistors 72 and 74, and the capacitor 76.
This misfiring condition can also be caused by an overheat signal produced by a temperature sensor 72 which is suitably secured to the engine 14. This overheat signal will cause a switch contact 82a to close. When switch contact 82a closes, an electrical series loop is created with a buzzer 84 and the battery 42 which will cause an audibly perceptible output indicative of the overheat condition. It should be noted that a light emitting diode (LED) 86 may also be provided in the place of the buzzer or in addition thereto via a parallel electrical connection across the buzzer 84 to provide a visually perceptible output of the overheat condition.
When the switch contact 82a closes, a speed reduction signal will be transmitted through the OR gate 64 to the switch 66 to initiate a misfiring condition if the speed of the engine 14 is currently greater than the predetermined low speed level. Thus, it will be appreciated that the OR gate 64 permits for two separate speed reduction signals to be generated by the protection system 10, one of which being in response to a low lubricant level condition, and the other being in response to an overheat condition. Accordingly, the OR gate has two inputs of which one is connected to the circuit junction between the switch contact 82a and the buzzer 84, and the other of which is connected to the circuit junction between the red lamp 54 and the cathode of the SCR 58.
It is important to note that once the speed reduction signal is generated by the low lubricant level condition, it will be maintained even though the lubricant supply of tank 34 is replenished. This function is provided by the self-holding circuit 56, since the SCR 58 will remain on even after the gate signal is removed. Thus, when the lubricant in the tank 34 is replenished and the lubricant level detector 34 causes the switch contact 40a to open, the SCR 58 will remain in a conducting condition. The SCR 58 can only be turned off when the operator manually opens the main switch 48 to remove the source of electrical power or current flow through the SCR 58. Accordingly, it will be appreciated that the unique combination of circuit components in the protection system 10 will prevent an unintended termination of the misfiring condition when the lubricant tank 34 is being replenished.
It should also be noted that while the engine 14 is shown in FIG. 1 to be a single cylinder engine, the principles of the present invention are also applicable to multicylinder engines. Similarly, even though the present invention is particularly advantageous in connection with outboard motor engines equipped with capacitive discharge ignition systems, it should be understood that the present invention may be used with other types of engines and ignition systems. Additionally, in an outboard motor application, the storage tank 34 may be mounted directly on the engine or located remotely from the engine. Furthermore, it should be appreciated that the transistor 78 and the SCR 58 may be replaced by other suitable controlled conduction devices which can perform the same function as these circuit components.
Referring to FIG. 2, a second embodiment of a protection system 100 according to the present invention is shown. A magneto generator is generally designated by the reference numeral 102. The magneto generator 102 includes a charging coil 104 and a pulser coil 106. The charging coil 104 and pulser coil 106 provide their signals and charges to a CD ignition circuit, indicated generally by the reference numeral 108.
The CDI circuit 108 includes a charging capacitor 110 that is charged from the charging coil 104 through a rectifying diode 112 to a polarity as shown in FIG. 2. A charge will be built up on the capacitor 110 during rotation of the engine crankshaft until an appropriate tripping device such as a rotating magnet causes a voltage to be generated in the pulser coil 106 to indicate that the crankshaft is in the appropriate position to demand firing of a spark plug 114. Of course, there will be one spark plug for each cylinder of the engine and the circuit shown in FIG. 2 is that associated with only a single cylinder of the engine. It should be understood that there will be corresponding circuits for each of the spark plugs of a multi-cylinder engine. However, it should also be understood that other ignition circuits than that illustrated may be used in conjunction with the invention.
The spark plug 114 is in circuit with a secondary winding of an ignition coil 116. The primary winding of the coil 116 is in circuit with the charging capacitor 110 and is adapted to be discharged to ground through an SCR 118 under the control of a circuit energized by the pulser coil 106. A trigger signal from the pulser coil 106 is transmitted through a diode 120 and capacitor resistor circuit 122 to the gate of the SCR 118 so as to turn it on and cause the capacitor 110 to discharge. This discharge through the primary winding of the ignition coil 110 will cause a voltage to be induced in the secondary winding which will fire the spark plug 114 in a known manner. A diode 124 is placed between ground and the connection of the coil 104 to the diode 112 for providing a circuit during the negative half wave of the charging coil 104. A similar diode 126 is provided between the capacitor 110 and the primary of the ignition coil 116 and ground. This portion of the ignition system may be considered to be generally conventional and forms no part of the invention.
The lubricant storage tank 128 of this embodiment includes a sensing device 130 for determining the level or amount of lubricant in the tank. The sensing device 130 includes a magnetic float 132 which reciprocates along a vertical column 134 in response to the level of lubricant in the tank 126. The column 134 includes two reed switches 136a and 136b which actuate in response to the proximity of the magnetic float 132. The actuation of the reed switch 136a controls a relay 138, while the actuation of the reed switch 136b controls a relay 140. The relay 138 is provided with switch contacts 142a and 142b, while the relay 140 is provided with switch contacts 144a and 144b.
Similar to the circuit construction of FIG. 1, the protection system 100 includes a generating coil 146, a diode rectifier bridge 148, a battery 150, a main switch 152, a green lamp 153, a yellow lamp 154, a red lamp 156, and a self-holding circuit 158 which includes an SCR 160. However, in contrast to FIG. 1, it should be noted that in the protection system 100 of FIG. 2, the connections to the diode rectifier bridge 148 are now such that each of the parallel circuit legs containing the green, yellow and red lamps are connected at one end thereof to ground.
Briefly, in operation, it will be seen that when the lubricant level in the tank 136 is that as shown in FIG. 2, the switch contacts 142b and 144b will be closed, while the switch contacts 142a and 144a will be open. Accordingly, the yellow lamp 154 will turn on from the power supplied by the battery 150. If the lubricant supply in the tank 126 is replenished, then the red switch 136b will actuate and cause the relay 140 to close the switch contact 144a and open the switch contact 146b. This will turn on the green lamp 153, while turning off the yellow lamp. However, if the lubricant level continues to decrease to the predetermined low lubricant level, than the reed switch 136a will actuate and cause the relay 138 to close the switch contact 142a and open the switch contact 142b. This will turn off the yellow lamp 154 and turn on the red lamp 156 upon the conduction of the SCR 160.
When the SCR 160 conducts a speed reduction signal will be produced on a conductor 162 having a connection to the anode of the SCR 160. This speed reduction signal is transmitted through a diode 164 to an engine speed control circuit 166. As in protection system of FIG. 1, the protection system 100 of FIG. 2 will also produce a speed reduction signal in response to the overheat condition. The switch contact 167 will close in response to the overheat condition and cause a buzzer 168 connected between conductors 162 and 170 to produce an audibly perceptible output indicative of the overheat condition.
In response to the speed reduction signal, the engine speed control circuit 166 is effective to cause the spark plug 114 not to be fired for increasing time intervals during a given period of time so that the spark plug 114 will only fire once every several revolutions of the engine until the speed is reduced to a level wherein the consumption of lubricant will be substantially reduced. The engine speed control circuit 166 includes a wave form shaping circuit 172 that receives the outputs from the pulser coil 106 and generates a square wave form pulse from them. This pulse is transmitted to a frequency to voltage converter 174 that provides an output voltage V n that is indicative of the engine speed. When the speed reduction signal is present on conductor 162, an input will also be provided to an oscillation circuit 176 which receives an input from the frequency to voltage converter 174 in the form of the signal V n .
The speed reduction signal also causes power to be delivered through a diode 178 to a delay circuit 180 which has an output V r that is also delivered to the oscillator circuit 176. The time delay circuit 180 operates like a capacitor in that its output signal V r decays along a curve as shown in FIG. 3.
The oscillator circuit 176 has an output voltage V a that is generated for a time period which is varied in accordance with the difference between the voltages V n and V r . The output of the oscillator circuit 176 is shown on the bottom line curve of FIG. 6 wherein the output extends for a period T 1 during a preset time interval T. As may be seen from this figure, the time T 1 continues to increase until the voltage V r has decayed to the point T 1 at which it is constant for a fairly substantial time period. During the time T 1 when the oscillator 176 is providing its high output, the firing of the spark plug 114 will be disabled.
This disabling is achieved by providing a shunting circuit that prevents charging of the capacitor 110. This shunting circuit includes an SCR 182 that has its output connected to ground via a resistor 184. The SCR 182 has its gate controlled by a gate circuit 186 that receives the output from the oscillator circuit 176 and which energizes the gate of the SCR 182 for a time T 1 as set by the oscillator circuit 176. An LED 188 and a diode 190 may also be included to provide a flashing indication that the ignition is being disabled to reduce the engine speed.
It should be noted that the time T 1 is effective to stop firing of the spark plug 114 for a given time interval during a given time period. Hence, the spark plug 114 will not fire for each revolution of the engine and the engine speed will, accordingly, be reduced so as to reduce the consumption of lubricant from the tank 126.
Referring now to FIG. 4, a schematic diagram of a portion of third embodiment of a protection system 200 according to the present invention is shown. The remainder of the protection system 200 may be similar to the circuitry for the protection system 100 shown in FIG. 2. It should be noted however that the protection system 200 is adapted to operate directly from the reed switches 136a and 136b shown in FIG. 2. The protection system 200 also includes a buzzer 201 to provide an audibly perceptible output indicative of the presence of an overheat condition.
When the reed switch 136b is closed, a green lamp 202 will be turned on. Similarly, when the reed switch 136a is closed, a red lamp 204 will be turned on. The closing of the reed switch 136a will also cause an SCR 206 to be gated on. This will produce a speed reduction signal which will be transmitted through a diode 208. In this embodiment, the self-holding circuit 200 includes the SCR 206, and a capacitor 212.
When both of the reed switches 136a and 136b are open, a yellow lamp 214 will turn on. The yellow lamp 214 is connected to the collector terminal of a transistor 216 which will be rendered conductive to permit current to flow through the yellow lamp at this time. The conduction of the transistor 216 is controlled by the voltage dividing resistors 218 and 220.
When the green lamp 202 is turned on, the diode 222 provides a current path which will maintain the voltage at the base of the transistor 216 at a level below its threshold turn on point. Similarly, during the time that the red lamp 204 is on, the diode 224 provides a current path which will maintain the voltage at the base of the transistor at a level below its threshold turning on point.
Referring to FIG. 5, a schematic diagram of a portion of a protection system 300 according to the present invention is shown. Since the protection system 300 of FIG. 5 is similar in construction and operation to the protection system 200 of FIG. 4, all corresponding circuit components will be identified with the same reference numerals primed. The principle difference between these two protection systems is that the protection system 200 employs LEDs instead of lamps. Accordingly, the protection system 300 is provided with a green LED 302, a yellow LED 304, and a red LED 306. It should also be noted that the protection system 300 does not require a transistor corresponding to the transistor 216 of FIG. 4. Rather, a diode 308 provides a shunt path to ground out the yellow LED 304 when the green LED 302 is turned on, and the diode 310 provides a shunt path to ground out the yellow LED 304 when the red LED 306 is turned on.
The various embodiments which have been set forth above were for the purpose of illustration and were not intended to limit the invention. It will be appreciated by those skilled in the art that various changes and modifications may be made to these embodiments described in this specification without departing from the spirit and scope of the invention as defined by the appended claims. | A protection system for a two-cycle outboard motor engine having a separate lubricant storage tank. The protection system generally includes a sensing device associated with the lubricant storage tank for detecting a low lubricant level condition, a first circuit for producing a speed reduction signal in response to the detection of this condition, a second circuit for gradually reducing the speed of the engine in response to the speed reduction signal even though the engine throttle control may be set for a higher speed, and a switch for manually terminating this speed control. The first circuit includes a controlled conduction device for maintaining the presence of the speed reduction signal after the low lubricant level condition is no longer present until the switch is actuated. | 5 |
FIELD OF THE INVENTION
The present invention relates generally to a pill tray for pharmacy use, and more particularly to a pill tray that allows full visual verification of the contents therein to ensure prescription consistency. Specifically, the present invention relates to a pill tray that prevents the commingling of pills and minimizes prescription fill errors during the often repetitive process of prescription verification.
BACKGROUND
The filling of prescriptions by automated systems has been implemented in many pharmacy practice settings to improve drug distribution, control inventory, reduce labor and decrease medication errors (See, e.g., “Implementation and evaluation of an automated dispensing system,” Am. J. Health - Syst Pharm. 1995, 52:823-8; “Medication cart-filling time, accuracy, and cost with an automated dispensing system,” Am. J. Hosp. Pharm. 1994; 51:1193-6). Despite these benefits, and contrary to expectations, studies have demonstrated that the number of prescription filling errors tends to increase with the implementation of automated systems.
In 2012 all automatically filled prescriptions were required to undergo a process known as Full Visual Verification (FVV). This process requires a pharmacist to pour the contents of each automatically filled prescription vial onto a counting tray to ensure product consistency. Upon verification that a prescription contains the correct type and number of pills, the pharmacist transfers the contents of the counting tray back into the prescription vial. The high volume of prescriptions filled in a typical pharmacy each day often requires the pharmacists to perform FVV for multiple automatically filled prescriptions in sequence. The highly repetitive process of transferring large numbers of pills to and from their respective containers naturally lends itself to errors. One such error, with potentially life threatening consequences, is commingling of medications due to the inadvertent transfer of stray pill(s) from one prescription vial to another. Structural features of the pill tray itself, such as crevices in which pills become temporarily lodged and/or blind spots that limit the pharmacist's ability to identify stray pills, are a significant factor in these comingling events. In view of the unlimited variety of pill sizes, colors and shapes (e.g., round, oblong, oval, elliptical, square, cylindrical, rectangular, diamond-shaped, cone-shaped triangular, crescent-shaped, trapezoidal, pentagonal, hexagonal, heptagonal, octagonal etc.) even minor surface disruptions within a pill tray represent potential areas in which a pill may become lodged. What is needed is an improved pill tray that allows the pharmacists to verify the accuracy and consistency of prescription contents in a safe and efficient manner.
SUMMARY OF THE INVENTION
In one aspect, the present invention is directed to a pill counting apparatus comprising a first trapezoidal portion comprising a substantially planar first floor surface comprising first, second, third and fourth sides; the first and third sides of the first trapezoidal portion being substantially parallel to each other; the first side of the first trapezoidal portion characterized by a length that is shorter than the third side of the first trapezoidal portion; a second trapezoidal portion comprising a substantially planar second floor surface comprising first, second, third and fourth sides; the first and third sides of the second trapezoidal portion being substantially parallel to each other; the first side of the second trapezoidal portion characterized by a length that is shorter than the third side of the second trapezoidal portion; the third side of the second trapezoidal portion adjoining the first side of the first trapezoidal portion; the substantially planar second floor surface forming an obtuse angle with respect to the substantially planar first floor surface; an open-ended spout extending from the second trapezoidal portion, the spout comprising a third floor surface adjoining the first side of the second trapezoidal portion; a common sidewall extending upwards from the first floor surface, the second floor surface and the third floor surface; wherein the first trapezoidal portion, the second trapezoidal portion, the spout and the sidewall together define a base portion; and a substantially transparent surface covering the second floor surface, the substantially transparent surface being immoveable with respect to the base portion.
In another aspect, the present invention is directed to a method of verifying the consistency of a prescription using the pill counting apparatus of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Non-limiting embodiments of the present invention will be described by way of reference to the accompanying figures, which are schematic and are not intended to be drawn to scale. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention. In the figures:
FIG. 1 depicts a top view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 2 depicts a top view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 3 depicts a top view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 4 depicts a top view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 5 is a cross-sectional view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 6 is a front elevational view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 7 is a front view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 8 is a top view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 9 is a side-elevational view of a pill tray, in accordance with an embodiment of the present invention.
FIG. 10 is a side-elevational view of a pill tray, in accordance with an embodiment of the present invention.
Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
While various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.
To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as “a,” “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.
The phrase “and/or,” as used herein should be understood to mean “either or both” of the elements being referred to, i.e., elements that are conjunctively present in some instances and disjunctively present in other instances. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to “A and/or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.
It will be understood that the term “preferably” as used throughout the specification refers to one or more exemplary embodiments of the invention and therefore is not to be interpreted in any limiting sense. It will be further understood that terms of orientation and/or position as may be used throughout the specification, such as upper, lower, rear, side, forward, downward, upward, inner and so on, as well as their derivatives and equivalent terms, relate to relative rather than absolute orientations and/or positions.
Referring to the drawings, and to FIG. 1 in particular, a pill counting apparatus 1 in accordance with an exemplary embodiment of the present invention is illustrated. The apparatus 1 may be interchangeably referred to herein as a “pill tray” or a “pharmacy tray.” As referred to herein, a “pill” is any suitable pharmaceutical dosage form. The pill counting apparatus preferably comprises a first trapezoidal portion 9 , second trapezoidal portion 19 , open-ended spout 40 , common sidewall 50 and substantially transparent surface 70 . Together the first trapezoidal portion 9 , second trapezoidal portion 19 , spout 40 and sidewall 50 define base portion 60 ( FIG. 2 ).
As illustrated in FIGS. 3 and 4 , first trapezoidal portion 9 comprises a substantially planar first floor surface 10 having first 11 , second 12 , third 13 and fourth 14 sides. First side 11 and third side 13 are substantially parallel to each other, with first side 11 having a length that is less (i.e., shorter) than that of third side 13 . The second trapezoidal portion 19 comprises a substantially planar second floor surface 20 having first 21 , second 22 , third 23 and fourth 24 sides. First side 21 and third side 23 are substantially parallel to each other, with first side 21 having a length that is less (i.e., shorter) than that of third side 23 . Third side 23 of second trapezoidal portion 19 adjoins first side 11 of second trapezoidal portion 9 . As shown in FIG. 5 , second floor surface 20 form an obtuse angle 30 with respect to first floor surface 10 . Common sidewall 50 extends upward from first floor surface 10 , second floor surface 20 and third floor surface 43 (below), as shown in FIGS. 5 and 6 .
Without intending to limit the present invention to any specific dimensions, in one embodiment, the height of sidewall 50 as measured from first floor surface 10 is preferably at least 1.5 inches and more preferably at least 2.0 inches. The height of sidewall 50 as measured from third floor surface 43 is preferably within the range of 1.0 to 1.5 inches. The thickness of sidewall 50 , first floor surface 10 and second floor surface 20 are all preferably within the within the range of 0.10 to 0.30 inches. The third side 13 of first trapezoidal surface portion 9 preferably has a length of at least 7.0 inches, more preferably at least 8.0 inches. The overall length of the pill counting apparatus (i.e., from third side 13 to spout 40 ) is at least 7.0 inches.
As illustrated in FIGS. 6 and 7 , open-ended spout 40 extends from second trapezoidal portion 19 , and includes a third floor surface 43 that adjoins first side 21 of the second trapezoidal portion 19 . As used herein, the term “spout” refers to any nozzle, funnel other opening through which the liquid or solids contents of a container may be passed or poured. Spout 40 is preferably shaped to fit within the opening of standard prescription vials such that the contents of apparatus 1 may be poured directly into a container such as a prescription vial. Without intending to limit the present invention to any specific dimensions, in one embodiment, open-ended spout 40 has a height of at least 1.0 inches.
As illustrated in FIGS. 8-10 , substantially transparent surface 70 covers second floor surface 20 and is immovable with respect to base portion 60 . In another embodiment, substantially transparent surface 70 covers second floor surface 20 and a portion of first floor surface 10 . In yet another embodiment, substantially transparent surface 70 covers a portion of third floor surface 43 (not shown). As illustrated in FIGS. 6 and 7 , in one embodiment the substantially transparent surface 70 comprises a downwardly extending lip 72 that engages side wall 50 . Substantially transparent surface 70 is preferably fixed to side wall 50 by a variety of attaching means known in the art including, but not limited to adhesives, glues, cements, welding, thermal bonding, injection molding and soldering. Alternatively, substantially transparent surface 70 is removably attached (i.e., for cleaning) to side walls 50 by a variety of attaching means such as clips, clamps, bolts and the like. Regardless of whether the substantially transparent surface 70 is fixed or removeably attached to the base portion 60 , it is said to be immoveable with respect thereto because, when in use, the portion of the substantially transparent surface 70 is fixed relative to the base portion 60 . The location of substantially transparent cover 70 relative to second floor surface 20 allows a user to visualize the entire base portion 60 such any pills lodged within pill counting apparatus 1 may be identified. Without intending to limit the present invention to any specific dimensions, in one embodiment, substantially transparent surface 70 is preferably characterized by a thickness within the range of 0.05 to 0.15 inches, a length of within the range of 6.5 to 7.5 inches and a width within the range of 2.5 to 3.5 inches.
Firm plastics and flexible adhesives known in the art may be used to provide an apparatus capable of withstanding repetitive use as well as high impact forces, such as when inadvertently dropped to the floor. In one embodiment, first trapezoidal portion 9 , second trapezoidal portion 19 and spout 40 are comprised of one or more polymers such as high density polyethylene (HDPE), low density polyethylene (LDPE) and polypropylene (PP). Similarly, transparent cover 70 is comprised of polymers such as high density polyethylene (HDPE), low density polyethylene (LDPE) and polypropylene (PP). Due to the wide variety pill colors and compositions (i.e., hard shelled capsule, soft shell capsules, gelatin capsules, capsules enclosing liquids, capsules enclosing powders etc.) the polymers used to form the first trapezoidal portion 9 , second trapezoidal portion 19 and spout 40 preferably include a color that provides a high contrast (for example, light blue) with such pills while limiting the build-up of chalky binding agents.
It will be understood that polymers such as the ones listed above are amenable to a variety of forming methods including, for example, vacuum forming and injection molding. These forming methods provide smoothly contoured transitions between the components of a pill tray, thereby avoiding edges, crevices, ledges, burrs etc. within which pills may become temporarily lodged. As best illustrated by FIG. 6 (shadowed lines), sidewall 50 extends upward from first floor surface 10 and second floor surface 20 with a smooth (e.g., rounded, tapered, gradual) contour that prevents pills from getting temporarily stuck. Spout 40 extends from second trapezoidal portion 19 with a similar smooth contour.
Pill counting apparatus 1 may comprise a variety of sizes and shapes, and is in no way limited to the dimensions provided in the present figures. In a preferred embodiment, pill counting apparatus 1 with the approximate dimensions of 8″×6″×2″ (length×width×height) is able to hold the contents of a standard 60 dram prescription flat across first floor surface 10 . The greater length of third side 13 of first floor 10 relative to first side 11 maximizes the area in which pills may be poured and counted. A user may count pills on first floor surface 10 while advancing them with a spatula towards spout 40 . The dimensions of pill counting apparatus 1 defined by first trapezoidal portion 9 and second trapezoidal portion 19 permits the user to tip pill counting apparatus 1 such that the pills slide and/or roll towards spout 40 . The height of sidewall 50 permits the entire contents of a prescription to be poured back into the original prescription vial without any spillage. Substantially transparent cover 70 allows the user to visually verify that no stray pills remain lodged within the pill counting apparatus. In the unlikely event that a stray pill is identified, the user may gently tap spout 40 against the outer rim of the prescription vial to dislodge the pill.
All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations can be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims. | The present invention provides a pill tray that allows a user to efficiently and reliably verify the contents of an automatically filled prescription. Design features that avoid the presence of sharp edges and allow visualization of the entire surface of the pill tray help reduce and/or eliminate the risk of commingling of pills between separate prescriptions. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a simulation system for a flexible AC transmission system (FACTS) connected online to a supervisory control and data acquisition (SCADA) system, and more particularly to an online simulation system for a FACTS which is capable of previously analyzing operation control effect of the FACTS through an online data connection with a SCADA system used for operating an electric power system.
[0003] 2. Description of the Related Technology
[0004] Since a FACTS such as a static synchronous compensator (STATCOM), a static synchronous series compensator (SSSC) or a unified power flow controller (UPFC) is operated based on an electronic inverter, it is possible to actively control an power load flow and a bus voltage of the power system with fast speed and to improve stability and efficiency of the power system.
[0005] However, since a conventional method of controlling FACTS is a manual set-point control method of allowing an operator of a power substation including the FACTS mounted therein or a local load dispatch center including a SCADA mounted therein to control the FACTS with his/her experience and intuition according to the status of a peripheral power system, there is a limitation in optimal operation and a variety of control. When the status of the power system is changed or the power system should be controlled so as to satisfy a special requirement, the FACTS cannot be appropriately controlled by only the experience and intuition of the operator. In particular, since the control effect of the FACTS has influence on an actual system, the selection of a control set-point is very important.
[0006] However, if the operator of the FACTS can check the effect on the power system in advance due to the control of the FACTS through a simulator, the operation of the FACTS becomes easy and system control reliability is remarkably improved.
[0007] In the related technology relating to a simulator for a FACTS, since a FACTS is a new technology, a simulator for a FACTS is hardly developed. Examples of the simulator for the FACTS include, for example, an offline simulator which is not connected to an external system such as a SCADA system. In this simulator, analysis is performed on the basis of power system data stored in the simulator. Since the offline simulator is not connected online to the SCADA system, the offline simulator does not aid the operator to control FACTS, unlike the present invention. Therefore, the offline simulator is developed for the purpose of education only.
SUMMARY OF THE INVENTION
[0008] Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an online simulation system capable of performing load flow computation through online real-time system data received from a SCADA system and a FACTS control set-point input by an operator so as to immediately check FACTS control effect according to control set-point, and acquiring an optimal FACTS control set-point.
[0009] In accordance with the present invention, the above and other objects can be accomplished by the provision of a simulation system for FACTS connected online to a SCADA, including: the SCADA which periodically acquires power system line data; and a FACTS simulator which receives the power system line data from the SCADA and performs load flow computation of an power system, and includes a database server for receiving and storing the power system line data from the SCADA, a man machine interface (MMI) for allowing an operator to input a FACTS control set-point, a load flow computation analysis module for performing the load flow computation of the power system on the basis of the power system line data received from the database server and the control set-point received from the MMI, and a power system display module for displaying the analyzed result of the load flow computation analysis module. Here, the power system line data may include bus voltage, real and reactive power flow, and an operation information of a circuit breaker and a relay.
[0010] The MMI of the simulator is used to input control set-points of the FACTS which is being operated in the power system, and the control set-points include a bus voltage, real and reactive power flow if the FACTS is a UPFC. The MMI of the simulator sends these control set-points to the load flow computation module. The load flow computation module performs the load flow analysis on the basis of the inputted power system data and the FACTS control set-points and sends the result to the power system display module. The power system display module displays voltages of buses and power flow of transmission lines and is fundamentally similar to a SCADA screen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0012] FIG. 1 is a view showing the whole configuration of a simulation system for FACTS connected online to a SCADA according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] Hereinafter, a simulation system for a FACTS connected online to a SCADA according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.
[0014] FIG. 1 is a view showing the whole configuration of a simulation system for a FACTS connected online to a SCADA according to an embodiment of the present invention.
[0015] As shown in FIG. 1 , the simulation system for the FACTS connected online to the SCADA according to the present invention includes a SCADA 10 and a FACTS simulator 20 which receives power system line data from the SCADA 10 and performs load flow computation of an power system. The FACTS simulator 20 includes a database server 11 , a man machine interface (MMI) 12 , a load flow computation module 13 and a system display module 14 .
[0016] The SCADA system 10 periodically acquires the power system line data in accordance with an update period. The power system line data acquired by the SCADA 10 is required for the FACTS simulator. For example, the power system line data includes, for example, analog data such as bus voltage data, real and reactive power flow data, or digital data related to operation information of a circuit breaker or a relay.
[0017] The database server 11 of the FACTS simulator 20 receives and stores the power system line data acquired by the SCADA 10 . The database server 11 is connected online to the SCADA 10 to receive and store the power system line data in real time.
[0018] The power system line data stored by the database server 11 is sent to the load flow computation module 13 . When the database server 11 sends the power system line data to the load flow computation module 13 , the power system line data is converted into an input data format of an load flow computation algorithm mounted in the load flow computation module 13 . The load flow computation module 13 previously includes FACTS (STATCOM, SSSC and UPFC) load flow models in the algorithm. The load flow computation module 13 receives a FACTS control set-point according to the operation of an operator from the MMI 12 , in addition to the power system line data of the database server 11 . If the FACTS device is the UPFC, the MMI 12 sends a control set-point relating to a bus voltage, real and reactive power flow to the load flow computation analysis module 13 .
[0019] When the operator directly inputs the control set-point required for the FACTS through the MMI 12 , the input control set-point is converted into a control input value of the FACTS load flow computation model included in the load flow computation module 13 and the converted control input value is then sent to the load flow computation module 13 .
[0020] The load flow computation module 13 performs general load flow computation on the basis of the power system line data received from the database server 11 and the control set-point received from the MMI 12 .
[0021] The analyzed result of the load flow computation analysis module 13 is displayed on the power system display module 14 . At this time, load flow computation information displayed on the power system display module 14 includes voltages and phases of the buses and power flow values of transmission lines. Such load flow computation information indicates the effect of the FACTS in a steady state of the power system according to the control of the FACTS set-point.
[0022] As described above, according to the present invention, it is possible to provide a simulation system capable of analyzing power system control effect according to a FACTS control set-point selected by an operator and performing load flow computation of an electric power system using a FACTS model based on an input control set-point and real-time data of a SCADA system such that FACTS control effect is immediately checked. Accordingly, it is possible to improve control effect and control reliability of the FACTS.
[0023] According to a simulation system for a FACTS connected online to a SCADA system of the embodiment of the present invention, an operator of a FACTS can analyze system control effect in advance according to a control set-point and thus the operation effect due to optimal operation of the FACTS can be improved and operation reliability of the FACTS can be improved.
[0024] In addition, the simulation system can function as an operation assisting system of a FACTS operator of an electric power company or function as an education simulator capable of improving operation capability of the FACTS operator through a simulation function.
[0025] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the technology 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. | An online simulation system for a flexible AC transmission system (FACTS) which is capable of analyzing operation control effect of the FACTS in advance through an online data connection with a supervisory control and data acquisition (SCADA) system used for operating an electric power system. | 6 |
FIELD OF THE INVENTION
The present invention relates generally to radio frequency electromagnetic wave (RF) transmission equipment. More particularly, the present invention relates to an apparatus and method for broadcasting two FM radio signals at the same frequency using the same aperture space.
BACKGROUND OF THE INVENTION
FM radio is in wide use in the field of radio broadcast. The term FM includes, for example, any of the Frequency Modulation methodologies used or developed for signal broadcasting in a frequency band assigned by the U.S. Federal Communications Commission (FCC), nominally in the transmission range 88 MHz to 108 MHz, which is near the middle of the Very-High-Frequency (VHF) television broadcast band. These Frequency Modulation technologies include both analog FM and digital FM.
The radio industry and the FCC have at present standardized on the iBiquity® IBOC (In-Band-On-Channel) hybrid analog-digital transmission system. This system permits FM stations in the U.S. to broadcast analog and digital signals simultaneously on their currently allocated channel frequency, if they use a single antenna to perform the simulcast.
At present, all U.S. FM radio transmission channels are 200 KHz wide, with standard analog FM broadcast modulation occupying only the center 100 KHz of the channel and with the IBOC signal using the outer 50 KHz on each side of the analog part of the channel. This characteristic of the IBOC signal imposes a need for sharp-cutoff filters to maintain signal separation, both between adjacent channels and between the analog and digital portions of the transmission on a single channel.
As an additional consideration, the FCC stipulates that the transmitted digital signal is to be 20 dB lower in signal strength than the analog signal. This may intrinsically place the digital transmitting antenna in a field as much as 10 times stronger than its own transmission.
One method of achieving an IBOC simulcast is to use two separate transmission systems feeding into two separate antennas on a single tower. Since the vertical position at which an antenna is mounted on a tower directly affects the antenna's achieved coverage, it would be desirable to collocate the analog and digital antennas not only on the same tower, but also at the same height above the ground. Further, since the azimuth pattern of an FM antenna is highly dependent on the interaction between the radiating device and the cross section of the tower structure, it would be desirable to mount both the analog and digital antennas in the same orientation to the tower.
When adding digital FM coverage to towers already in use for analog FM, a concern arises because many towers are full—that is, the towers have no additional aperture space available—so that some FM broadcasters may be required to interleave a second antenna within the aperture of their existing antenna. This introduces a challenge, because the analog and digital signals occupy the same segment of the frequency spectrum, yet are required to be isolated from each other. The current requirement for isolation between the IBOC digital signal and the analog signal is on the order of 35 dB. If the IBOC and analog antennas are to share the aperture, it is desirable to provide satisfactory isolation so that filtering requirements are kept within desirable ranges.
Accordingly, there is a need in the art for a method and apparatus to achieve isolation between separate in-channel FM antennas sharing common aperture space.
SUMMARY OF THE INVENTION
Preferred embodiments of the method and apparatus achieve isolation at least to some degree between separate in-channel FM antennas sharing common aperture space, employing two antennas that are circularly polarized with opposite orientations.
In a first aspect, an enhanced-isolation shared-aperture digital and analog FM antenna pair is comprised of two independent circularly-polarized FM transmitting antennas on a tower. In another aspect, each of the two antennas has at least one element, where each element of each antenna can radiate a circularly-polarized RF broadcast signal. In still another aspect, each of the two antennas has a plurality of substantially identical, independently-mounted, individually driven elements spaced vertically along the tower. In yet another aspect, elements of one of the antennas are symmetrical and opposite to the elements of the other antenna, so that the elements of one of the antennas, when driven, radiate a left-hand circularly polarized signal, and the elements of the other antenna, when driven, radiate a right-hand circularly polarized signal. In another aspect, the locations of the elements comprising the first antenna are interleaved with the locations of the elements comprising the second antenna.
In another aspect, an apparatus for transmitting digital and analog FM radio signals from a common aperture space comprises means for radiating a first FM signal with a first circular polarization and means for radiating a second FM signal with a second circular polarization opposite to that of the first signal. Such an apparatus may be further comprised of means for accepting a first broadcast-level signal from a transmission line and means for distributing the energy of the first broadcast-level signal among multiple transmitting elements with signal-level balance and phase relationships required to create a first circularly-polarized transmission, as well as means for accepting a second broadcast-level signal from a transmission line and means for distributing the energy of the second broadcast-level signal among multiple transmitting elements with the signal-level balance and phase relationships required to create a second circularly-polarized transmission with polarization opposite to that of the first signal.
In yet another aspect, a method for simulcasting analog and digital FM broadcasts from a single aperture space comprises the steps of driving a first antenna with a first circularly-polarized signal at a particular channel frequency and driving a second antenna with a second circularly-polarized signal at the same channel frequency, where one of the signals is an analog transmission and the other is a digital transmission, and where the polarizations of the two signals are opposite.
There have thus been outlined, rather broadly, the more important features of the invention, in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments, and of being practiced and carried out in various ways. It is also to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description, and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods, and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a transmission system combining analog and digital FM radio broadcast signals in an IBOC environment.
FIG. 2 is a more detailed view of the two antennas and the associated tower-top apparatus used for a combined IBOC dual broadcast system.
FIG. 3 is a diagram of a single circularly polarized multi-element antenna for use in an analog-only or a digital-only (non-IBOC) environment.
FIG. 4 is a diagram of an interleaved pair of circularly polarized multi-element antennas configured for opposite-polarization transmission in an IBOC environment.
FIG. 5 is more detail view of diagram of FIG. 4 .
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the invention provide a method and apparatus for achieving isolation at least to some extent between separate in-channel FM antennas sharing common aperture space. Preferred embodiments of the invention will be described with reference to the figures, in which like reference numerals refer to like elements throughout.
FIG. 1 shows an FM radio transmission system including a single content source feeding two complete signal paths. A digital programming source 10 provides a digital signal stream 12 . The digital signal stream 12 feeds a digital transmitter 20 directly. The output of the digital transmitter 20 feeds a circulator 22 with an associated dummy load 24 .
After processing of the digital signal stream 12 with digital-to-analog conversion 26 (D/A), the analog signal feeds an analog transmitter 32 . The full-power analog signal may drive its antenna 46 without a circulator, since its signal level is far higher than the digital signal level under current FCC regulations and the added isolation is superfluous.
The digital transmitter 20 and analog transmitter 32 outputs can send their respective signals independently up a tower 38 using a digital signal coax 40 and an analog signal coax 42 . Once the digital and analog signals are present near the digital and analog transmitting antennas 44 and 46 , they may be fed into a passive digital power divider 48 and a passive analog power divider 50 , respectively, in a configuration known in the art as branch or corporate feed. The outputs of the digital power divider 48 are distributed, using individual digital feed lines 52 that are preferably equal in length, to the respective digital antenna elements 54 . Similarly, the outputs of the analog power divider 50 are distributed, using individual analog feed lines 56 that are preferably equal in length, to the respective analog antenna elements 58 .
A power divider, as the term is used here, is for example a passive device that divides an input into a series of lower-energy duplicates of the original signal, in phase with each other but delayed by the intrinsic propagation time of the device. The exact timing of each of the divided signals may be adjusted with respect to the others by precise control of the length of the feed coax from the power divider to the individual radiating elements. Making the delays to the individual radiating elements unequal can adjust the beam tilt—the energy distribution as a function of the angle to the horizontal—of the radiated signal, and thereby affect the signal's reception range.
A circularly polarized signal transmitted as described above is detectable either by a suitable circularly polarized receiving antenna, namely one with the same handedness as the transmitting antenna, or by a linearly polarized receiving antenna, which has less gain with respect to the signal than does a same-handed circularly polarized antenna, but far higher gain with respect to the signal than does an oppositely-handed circularly polarized receiving antenna.
FIG. 2 provides a more detailed view of the items located at the top of the tower 38 . A feed from the digital signal power divider 48 via digital signal coaxial feed lines 52 energizes digital radiating elements 54 . Similarly, a feed from the analog power divider 50 via analog signal coaxial feed lines 56 energizes analog signal radiating elements 58 .
The signal energy may also be distributed directly up the tower 38 with tee junctions, a configuration known in the art as series feed, illustrated in FIG. 3 , which shows a single, non-IBOC antenna. FIG. 4 adds a second radiating arrangement of opposite polarization to form an IBOC-compliant combination. FIG. 4 shows on the lower of the two digital elements 54 a fitting that attaches the lower digital element 54 to the tower 38 while passing around and making no electrical contact with the analog coaxial line 56 . FIG. 5 shows the same elements enlarged, with the antenna coupling fitting 66 coupling the analog coax 56 to an analog antenna element 58 and the bypass fitting 68 allowing a digital antenna element 54 to be mounted in its preferred location without electrical contact to the analog coax. The digital elements 54 in FIG. 4 are fed by separate coaxial lines within the figure; whether their feed is series or branch is not shown. Series feed causes each of the elements to be excited with a signal delayed by one cycle from the previous element, a characteristic that can have no appreciable effect on the received FM radio signal. The difference shown in FIGS. 3 and 4 in the relative size of the analog coaxial line 56 and the digital coaxial lines 52 illustrates the hundredfold greater power that can be present in an IBOC-compliant system's analog signal. This power differential can permit a preferred embodiment for the digital signal to incorporate a smaller, lower-cost coaxial line with reduced wind loading, fewer joints, and easier installation, yet meet system requirements.
Where the elements 58 of the analog antenna are spaced one wavelength apart as shown in FIG. 3 , the analog output comprises a single circularly polarized transmission with acceptable uniformity around the tower 38 (that is, a substantially omnidirectional radiation pattern) despite the presence of the conductive tower structure. Polarization may be a function of antenna element 58 design, so that similar antenna elements of opposite handedness will radiate circularly polarized right-handed or left-handed signals.
Variations in vertical spacing between elements 58 can determine in part the characteristics of the beam pattern generated. Elements 58 spaced uniformly at one wavelength increments can produce a pattern at right angles to the tower, while elements 58 with spacing other than one wavelength, such as 9/10, 4/5, 3/4, and the like, can be used to reduce excessive upward radiation.
FIG. 4 illustrates the interleaving of digital antenna elements 54 at one-half-wavelength spacing with respect to the analog elements 58 , which establishes one-wavelength spacing between the digital antenna elements 54 themselves. This places the center of the aperture for the digital antenna within the aperture of the analog antenna, and nearly coincident with the center of the analog aperture. If the digital antenna elements 54 are designed to radiate a circularly polarized signal of opposite polarity to the corresponding analog apparatus, then there can be an intrinsic improvement, for example on the order of 10 dB, in the isolation between the digital and analog transmissions when compared to using two antennas of like placement but with the same polarization as each other. This represents a significant portion of the isolation required for collocated transmitting antennas at the same frequency, and can help reduce the filter and circulator hardware size and cost that would otherwise be required in implementing an IBOC system.
Spacing the digital antenna elements 54 equidistant between the proximate analog antenna elements 58 shown in FIG. 4 can minimize coupling of the analog signal to the digital line, which can in turn minimize the size of the apparatus needed in order to remove the signals coupled thereto.
In the example in FIGS. 3 and 4 , two elements of each of the digital antenna 44 and the analog antenna 46 of FIG. 1 are shown. Each element operating alone can create a circularly polarized signal, while adding more elements can increase range by increasing total radiated power capability and by increasing the directivity of the radiation pattern. Using a larger number of elements, for example up to about twelve in each antenna, is useful in some environments and will typically produce improved performance. Using large numbers of elements may incur greater complexity and necessarily takes up more physical height, the latter of which translates to a greater share of the typically limited aperture space within the confined environment of a transmission tower 38 .
Alternative embodiments of the invention may use only one element per antenna. In such embodiments, the apertures by definition do not overlap.
Achievement of the full 35 dB of isolation between the analog and digital transmissions in an IBOC system may require that the intrinsic 12 dB isolation of the two signals and the added 10 dB gained through use of oppositely polarized antennas be augmented by the use of a circulator or equivalent function in the digital transmitter signal path.
Circulators, such as the digital signal path component 22 in FIG. 1 , are passive devices that can allow RF signals to advance one node around a directional multi-port fitting with acceptable power losses. Following the digital signal path in FIG. 1 , outgoing RF from the digital transmitter 20 is allowed by the circulator 22 to advance from that circulator's first port 60 to its second port 62 , which leads to the digital-signal transmission line 40 . The digital-signal transmission line 40 in turn leads to the digital-signal antenna 44 . Coupled energy from the analog antenna 46 , as well as returning RF from other sources, such as reflections from connectors, antenna mismatches, and the like can travel in the direction opposite to the transmitted signal in the digital-signal transmission line 40 . Such energy reenters the circulator at its second port 62 and advances to its third port 64 , having been deflected by the circulator 22 from the digital-signal transmitter 20 . The third circulator port 64 feeds to a dummy load 24 , which transforms the unwanted energy to heat.
Since the digital signal may be 20 dB lower in signal strength than the analog signal, and the 12 dB intrinsic isolation and 10 dB added isolation of the invention may further attenuate digital signal energy coupled to the analog path, a circulator placed in the analog signal path may not be needed for a preferred embodiment.
Numerous styles of antenna elements can intrinsically radiate circularly polarized signals and are thus suitable for simulcasting an analog and a digital signal in a single aperture. Still other styles that do not intrinsically radiate circularly polarized signals can be forced to create such signals when driven by properly configured signals. Any pairs of antennas composed of a plurality of elements per antenna, capable of being configured to radiate oppositely circularly polarized signals, and further capable of being interleaved on a tower with their electrical centers located within +/−2 meters of each other, can potentially be incorporated into a system as described in the present invention.
A preferred embodiment of the invention uses ring-style antennas. In this embodiment, the helical direction in which the dipoles comprising the separate circularly polarized ring-style antenna elements are wound is opposite between the digital and analog antennas, effectively interleaving right-hand and left-hand polarized antennas in the same aperture. This achieves the required high level of isolation between the antennas collocated in the aperture.
Unlike the situation for broadcast television, current FCC regulations on FM radio transmission (e.g. 47 CFR 73.316) do not distinguish between right-hand and left-hand circular polarization. While horizontal polarization is standard, either right-hand or left-hand circular polarization is an acceptable alternative under current FCC regulations, as long as the total effective radiated power remains within the licensed limit. Further, it can be demonstrated that a right-hand circularly polarized antenna will exhibit significant rejection of any left-hand polarized signal and vice versa. This observation leads to an approach to increasing isolation.
An inherent advantage to increasing the isolation between the antennas is a reduction in mutual coupling. When a high level of isolation exists, the second antenna can be placed in the aperture of an existing antenna with minimal effect on the match of the existing antenna, thus potentially reducing field adjustment after installation. Since field adjustment may require repeatedly climbing the tower, energizing and deenergizing the transmitters, and painstakingly adjusting the apparatus, the process may be time consuming and costly. As such, it should be avoided if such avoidance is practical.
In comparison to more conventional techniques, interleaving oppositely-circularly-polarized antennas within an aperture can, in some embodiments, achieve an extra 10 dB of isolation.
Although the preferred embodiment is described for use with FM radio, application of the invention to other frequency bands and other modulation methodologies is possible.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention that fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | Each of a pair of antennas for broadcasting has multiple elements arranged vertically on the same tower. The antennas transmit circularly polarized signals of opposite polarization. The opposite circular polarization of the radiated signals increases their mutual isolation and permits broadcast of conventional FM-band signals and digital FM at the same frequency. The polarization technique allows the elements of the two antennas to share an aperture without degradation of function. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation of international application PCT/DE94/01085, filed Sep. 19, 1994, which designated the United States.
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation of international application PCT/DE94/01085, filed Sep. 19, 1994, which designated the United States.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an apparatus for cooling the coolant of the cooled gas turbine of a gas-turbine and steam-turbine plant; the latter comprises a waste-heat steam generator downstream of the gas turbine with heating surfaces which are connected into a water/steam loop of the steam turbine, and in which a first heat exchanger provided for cooling the coolant is linked to the secondary side of a second heat exchanger.
A gas-turbine and steam-turbine plant of this type is conventionally used for generating electrical energy. The aim is to provide an especially high temperature of the working medium at the inlet of the turbine of, for example, 1200° to 1500° C. so as to increase the power capacity of the gas turbine and therefore to achieve the highest possible efficiency. However, such a high turbine-inlet temperature entails material problems especially in respect of the heat resistance of the turbine blades.
2. Description of the Related Art
An increase in the turbine-inlet temperature is acceptable when the turbine blades are cooked to such an extent that they always have a temperature below the rated temperature limit of the turbine blade material. It has been known heretofore, for this purpose, from European patent specification EP 0 379 880 to branch off air compressed in a compressor assigned to the gas turbine and to cool the air serving as a coolant before the entry thereof into the gas turbine. It has also become known from European patent specification EP 0 519 304 A1 to use an air/water cooler for this purpose, by means of which the heat obtained during the cooling of the coolant is supplied to the water/steam loop via feed water used for this purpose. A disadvantage of this, however, is the increased outlay with respect to measurement and regulatory control, especially with regard to maintaining the necessary pressure and setting the quantity of the feed water extracted from the water/steam loop for coolant cooling. It has also become known from British Patent 2 264 539 A to transfer the heat obtained in cooling the coolant via an intermediate circuit to the feed water of the water/steam loop.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an apparatus for cooling the coolant of the gas turbine in a gas-turbine and steam-turbine plant, which overcomes the above-mentioned disadvantages of the prior art devices and methods of this general type and which assures good gas-turbine cooling, and that, as a result of an especially effective utilization of the heat obtained thereby, superior overall efficiency of the gas-turbine and steam-turbine plant is ensured. Quite importantly, also, the foregoing objects are to be satisfied with the least possible technological outlay and as inexpensively as possible.
With the foregoing and other objects in view there is provided, in accordance with the invention, an improvement in the cooling of a gas-turbine of a gas-turbine and steam-turbine plant. The latter includes a gas turbine and a waste-heat steam generator having heating surfaces located downstream of the gas turbine and connected in a water/steam loop of a steam turbine. An apparatus is provided for cooling a coolant of the gas turbine. The apparatus comprises:
a water/steam separating tank connected to the evaporator heating surface of the waste-heat steam generator;
an intermediate circuit including a first heat exchanger for cooling the coolant of the gas turbine, and a second heat exchanger, the second heat exchanger having a primary side communicating with the water/steam separating tank and a secondary side communicating with the first heat exchanger.
In accordance with an added feature of the invention, the water/steam separating tank has a water side and a steam side, the primary side of the second heat exchanger having a primary side inlet communicating with the water side and a primary side outlet communicating with the steam side of the water/steam separating tank.
In other words, the objects of the invention are satisfied with the second heat exchanger which is connected on the primary side to the water/steam separating tank, which is connected to the evaporator heating surface.
The heat claimed by cooling the coolant and transferred to the gas-turbine and steam-turbine process via the intermediate circuit, i.e., via a closed separate cooling circuit, is thus used to generate steam. Due to the fact that the quantity of secondary medium present in the intermediate circuit remains constant, there is no need for volume regulationg. Because the water/steam circuit is uncoupled from the intermediate circuit in flow terms, the pumping capacity for conveying the secondary medium in the intermediate circuit is especially low.
The coolant for cooling the gas turbine is a fluid which can be liquid or gaseous. Compressed air from an air compressor assigned to the gas turbine is preferably used as a coolant.
Depending on the temperature level required, the second heat exchanger can be connected to different heating surfaces of the waste-heat steam generator. Expediently, the second heat exchanger connected into the intermediate circuit on the secondary side is connected on the primary side to a water/steam separating tank connected to a low-pressure evaporator heating surface. The water/steam separating tank is advantageously connected on the water side to the primary-side inlet and on the steam side with the primary side outlet of the second heat exchanger.
A suitable pump is connected upstream of the first heat exchanger disposed on the primary side of the intermediate circuit for conveying the secondary medium flowing in the intermediate circuit and cooling the coolant. Furthermore, the second heat exchanger is expediently preceded on the primary side by a pump for conveying the water or water/steam mixture (tertiary medium) flowing therethrough out of the water/steam loop.
A feed conduit opens into the intermediate circuit for the purpose of additionally introducing water, especially deionized water, into the otherwise closed cooling loop.
In order to guarantee a sufficient cooling effect even in the case of operationally reduced steam generation; especially in the case of pure gas-turbine operation (single-cycle operation), an auxiliary cooler parallel to the first heat exchanger can be connected into the intermediate circuit.
The advantages achieved by the invention are, in particular, that, by the use of two heat exchangers in a closed intermediate circuit, an especially suitable return of heat into the overall process, at the same time with a simple mode of operation and at low outlay in measuring and regulating terms, is possible. Moreover, there is no need for a coolant exchange, unless, by the use of the same system, the secondary medium of the intermediate circuit is to be exchanged for one of a different kind.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an apparatus for cooling the coolant of a gas turbine in a gas-turbine and steam-turbine plant, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the single figure of the drawing:
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE of the drawing is a diagrammatic view of a gas-turbine and steam-turbine plant with an apparatus for cooling the gas turbine coolant.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The gas-turbine and steam-turbine plant shown diagrammatically in the FIGURE, comprises a gas turbine 2 with an upstream combustion chamber 4 and with a waste-heat steam generator 6 which is located downstream on the gas side. Heating surfaces of the steam generator 6 are connected in a water/steam loop 8 of a steam turbine 10. The heating surfaces are, in particular, a low-pressure preheater 12, a low-pressure evaporator 14 and a low-pressure superheater 16.
Located downstream of the steam turbine 10 is a condenser 18 which is connected via a condensate pump 20 to the low-pressure preheater 12. The latter is connected on the outlet side and, via a circulating pump 22, on the inlet side to a feed-water tank 24. The feed-water tank 24 is connected on the outlet side, via a feed-water pump 26, to a water/steam separating tank 28. Connected to this water/steam separating tank 28 are the low-pressure evaporator 14, on the water side, via a pump 30, and the primary-side inlet of a (second) heat exchanger 32. The steam side of the water/steam separator 28 communicates with the low-pressure superheater 16 and the primary-side outlet of the heat exchanger 32. The heat exchanger 32 is thus connected in parallel to the low-pressure evaporator 14 via the water/steam separating tank 28.
The (second) heat exchanger 32 is connected on the secondary side into an intermediate circuit 34, into which the primary side of a (first) heat exchanger 36 is connected. The latter is connected on the secondary side into a cooling-air conduit 38 opening into the gas turbine 2.
The cooling-air conduit 38 is connected to an air compressor 40 assigned to the gas turbine 2. The air compressor 40 and an electrical generator 42 driven by the gas turbine 2 are seated on a common shaft 44. A branch 46 of the cooling-air conduit 38 opens into the combustion chamber 4 assigned to the gas turbine 2.
A pump 48 and two power valves 50, 52 are connected into the intermediate circuit 34. An auxiliary cooler 56 can be connected into the intermediate circuit 34 via the valves 50, 52 and via a further power valve 54. The intermediate cooler 56 communicates via a conduit 58 with a compensating tank 60. The latter is also connected directly to the intermediate circuit 34 via a conduit 61. Moreover, a feed conduit 64 for additional water D (e.g. deionized water), provided with a valve 62 opens into the intermediate circuit 34.
When the gas-turbine and steam-turbine plant is in operation, fuel B is supplied to the combustion chamber 4. In order to generate the working medium for the gas turbine 2, the fuel B is combusted in the combustion chamber 4 together with compressed air L conveyed through the branch 46 and coming from the air compressor 40. The hot working medium or flue gas RG which results from the combustion and which is under high pressure is expanded in the gas. turbine 2. The flue gas thus does mechanical work by driving the gas turbine 2 and consequently the air compressor 40 and the generator 42. The expanded flue gas RG' emerging from the gas turbine 2 is introduced via a flue-gas conduit 66 into the waste-heat steam generator 6 and is utilized there to generate steam for the gas turbine 10. For this purpose, the flue gas stream and the water/steam loop 8 are oriented in counterflow relative to one another.
In order to achieve particularly good utilization of heat, there are conventionally produced steams at different pressure levels, the enthalpy of which is used for current generation in the steam turbine 10 driving a generator 68). In the exemplary embodiment, only the low-pressure stage is illustrated and described.
The expanded steam emerging from the steam turbine 10 passes into the condenser 18 and condenses there. The condensate is conveyed into the feed-water tank 24 via the condensate pump 20 and the low-pressure preheater 12. Some of the feed water is conveyed once more by means of the circulating pump 22, for further preheating, via the low-pressure preheater 12 and from there back into the feed-water tank 24. The preheated feed water is conveyed by means of the feed-water pump 26 out of the feed-water tank 24 into the water/steam separating tank 28. From there, the preheated feed water is guided via the pump 30 into the low-pressure evaporator 14, where it evaporates. The steam is separated from the remaining water in the water/steam separating tank 28 and is guided into the low-pressure superheater 16. The superheated steam passes from there into the steam turbine 10. The superheated steam is expanded in the steam turbine 10 and, at the same time, drives the latter and consequently the generator 68.
A partial flow t 1 of the preheated water from the water/steam separating tank 28 is guided via the heat exchanger 32, whereby the water evaporates at least partially. The heat necessary for this purpose is extracted from a secondary medium S flowing in the intermediate circuit 34. The steam or water/steam mixture generated in the heat exchanger 32 is likewise guided into the water/steam separating tank 28.
The secondary medium S of the intermediate circuit 34 cooled during heat transfer in the heat exchanger 32 serves for cooling compressed air L which is supplied to the gas turbine 2 from the air compressor 40. The heat transfer from the compressed air to the secondary medium S takes place in the heat exchanger 36. The air L cooled in the heat exchanger 36, hereafter designated as cooling air K, is supplied both to the rotor blades of the gas turbine 2 via a conduit 70 and to the guide blades of the gas turbine 2 via a conduit 72.
Should an additional cooling of the cooling air K for the gas turbine 2 be necessary, for example when, as the result of a shut-down of the steam-turbine plant, a sufficient recooling of the secondary medium S is not guaranteed solely via the heat exchanger 32, the auxiliary cooler 56 is put into operation. For this purpose, the valves 50 and 52 are at least partially closed and the valve 54 is opened. A cooling medium W, for example water, is consequently supplied to the auxiliary cooler 56. Changes in volume of the secondary medium S within the intermediate circuit 34 are compensated through the compensating tank 60. Moreover, deionized water D can be supplied to the intermediate circuit 34 via the feed conduit 64.
The use of an intermediate circuit 34 with two heat exchangers 32 and 36 achieves two primary goals: On the one hand, the water/steam circuit 8 of the steam-turbine plant and the cooling system--represented essentially by the cooling-air conduit 38 and the heat exchanger 36--are decoupled in terms of medium flow, and on the other hand they are thermally coupled to one another. The outlay in measuring and regulating terms for the cooling system and for the intermediate circuit 34, as well as with regard to the required pumping capacity within the intermediate circuit 34, is thereby particularly low. | A combined gas-turbine and steam-turbine plant includes waste-heat steam generator which is located downstream of the gas turbine. The heating surfaces of the waste-heat steam generator are connected in a water/steam loop of the steam turbine. The gas turbine is cooled and the heat obtained in that heat exchange is further utilized. An intermediate circuit is linked to a first heat exchanger which cools the coolant of the gas turbine and to a second heat exchanger which is connected in the water/steam loop. | 5 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to the gathering of information from locations to be provided with conditioned air by one or more HVAC systems.
[0002] The gathering of information from locations in which conditioned air is to be provided has heretofore been largely accomplished through the use of thermostats. These thermostats typically allow an individual to enter a preferred set point temperature indicative of the level of comfort that he or she desires. The thermostat also typically includes a sensor for sensing the actual temperature in the room. The difference between the entered setpoints and sensed temperatures are used to control one or more HVAC systems providing conditioned air to the locations.
[0003] There may be several people in a location that would have different feelings as to what the set point temperature should be. Individual thermostats do not allow these people to each individually provide their respective feelings of comfort. There is also no ability to identify who is requesting a particular level of comfort at a particular location.
SUMMARY OF THE INVENTION
[0004] A data collection system allows individual occupants in one or more locations to provide an indication as to their respective levels of comfort. The indications as to comfort level are preferably provided through personal computers in these locations. Each computer is programmed to display a menu of comfort level options that may be selected by the user of the computer. Each computer is operative to also request that the user enter an identification. In the event that the entered identification is recognized, the computer will store the selection as to comfort level and timely provide the stored results to a network computer. The network computer is operative to analyze the comfort level information from these computers and send one or more commands to the HVAC system providing conditioned air to the locations.
[0005] In an exemplary preferred embodiment, individuals may select one of three different levels of comfort at their respective computers. The computers are grouped in accordance with the control of conditioned air to a particular location. Information from each of the computers is gathered and analyzed by a network computer which produces preferred levels of comfort for each location. This information as to preferred levels of comfort for each location is sent to an HVAC system control with damper controls that govern the flow of conditioned air to the various locations. The disclosed exemplary embodiment deals with levels of comfort for temperature in a location. The invention is, however, equally applicable to other measurements of comfort that may be analyzed and thereafter acted upon, including for instance, humidity or air flow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Further advantages of the present invention will be apparent from the following detailed description in conjunction with the accompanying drawings, wherein:
[0007] [0007]FIG. 1 illustrates an office building with a number of offices grouped into a number of office area locations;
[0008] [0008]FIG. 2 illustrates a display menu as to comfort levels appearing on the screens of computers in the offices of FIG. 1;
[0009] [0009]FIG. 3 illustrates a program located in the computers which generate the display menu of FIG. 2;
[0010] [0010]FIG. 4 illustrates a program located on a network computer which collects and analyzes the menu selections entered into the programmed computers in the offices of FIG. 1;
[0011] [0011]FIG. 5 illustrates an exemplary program that may be executed by a processor within an HVAC system control in response to one or more commands from the network computer executing the program of FIG. 4; and
[0012] [0012]FIG. 6 illustrates the display of an alternative comfort level menu to that of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] Referring to FIG. 1, an HVAC system 10 provides conditioned air to a number of individual office area locations such as office area location 12 and office area location 14 . Each office area location will carry a particular office area index value for purposes of identifying comfort level data originating from the particular office area location. This is indicated by office area location 12 being office area 1 whereas office area location 14 is identified as office area N.
[0014] Each office area location is seen to include a number of individual personal computers such as computer 16 located in an office 18 . Each office within office area location 12 is identified by an office index “K” where K=for instance 1 for office 18 and is for instance another value for office 20 .
[0015] Each computer within an office in a particular office area location is preferably connected to a network computer 22 . As will be explained in detail hereinafter, the network computer 22 is operative to collect comfort level information entered in each of the computers within the individual offices of each office area location. The collected information is analyzed by particular office area index value. The network computer is thereafter operative to generate overall indications as to level of comfort in each office area. These overall indications as to comfort level are preferably indexed in accordance with the office area index and provided to an HVAC system control 24 . The HVAC system control 24 is operative to control the HVAC system 10 so as to provide appropriate amounts of conditioned air to each of the office areas in accordance with the information received from the network computer 22 .
[0016] Referring now to FIG. 2, a comfort level menu 30 appearing on the screen 32 of an office computer such as office computer 16 is shown. The comfort menu 30 preferably includes three levels of comfort for the temperature in the office in which the computer is located. These comfort levels are expressed as “TOO HOT”, “JUST RIGHT”, or “TOO COLD”. The office computer preferably includes a point and click operating system which allows the user to click on the particular comfort level being experienced by the occupant of the office. The occupant of the office thereafter preferably clicks on an icon 34 labeled “ENTER” after making his or her selection as to comfort level from the menu 30 .
[0017] Referring now to FIG. 3, the software routine executed by a processor within each office computer is shown. The routine begins with a step 35 wherein a comfort control menu is displayed on the computer screen of the office computer. The comfort control menu could be the particular comfort control menu 30 of FIG. 2. The processor proceeds to a step 36 and inquires as to whether an “ENTER” decision has been made. An “ENTER” decision will have been made when a person clicks upon the “ENTER” icon 34 appearing on the computer screen 32 in FIG. 2. When an “ENTER” decision has been made, the processor proceeds from step 36 to a step 37 and issues a request on the screen of the office computer for a user identification. The processor awaits the entry of the user identification in step 38 before proceeding to a step 39 and inquiring as to whether the entered user identification compares favorably with one or more stored user identifications. The stored user identifications are preferably stored in a memory associated with the processor in the office computer. These stored user identifications have preferably been previously entered in accordance with a routine that permits the entry of such identifications. This routine may itself require one or more interactive communications requiring the user to first enter a key or code that allows them to proceed to enter their own unique user identification. In this manner, only people who are normally occupants of the location will be given a key or code that would allow them to store their own unique user identification. In any event, if the entered user identification noted in step 38 compares favorably with the previously stored identification in step 39 , then the processor will proceed to store the menu selection made from the displayed menu of step 35 . For a menu selection made from the menu 30 , the processor preferably stores the selection as “T_INPUT_K”. The value of “K” within the stored menu selection variable “T_INPUT_K” will be the office index value for the particular office in which the office computer is located. The stored menu selection in “T_INPUT_K” is preferably 1 for a comfort level selection of “TOO HOT”, 0 for a comfort level selection of “JUST RIGHT”, and −1 for a comfort selection of “TOO COLD”. Referring again to step 39 , in the event that the entered user identification does not compare favorably with the previously stored user identification, then the processor proceeds to display a message in step 41 that entry of the menu selection has been denied.
[0018] Referring now to FIG. 4, the computer program implemented by the processor within the network computer 22 is shown. The program begins with a step 42 wherein the office area index, “N” is set equal to 1. A “TIMER_CLOCK” is also set equal to 0 so as to thereafter begin clocking time from a system clock associated with the processor in the network computer. The processor proceeds to step 44 and reads “T_INPUTS” for the office area index, “N”. Since “N” will be initially set equal to 1, the processor will be reading the menu selections for the office computers in office area 12 . The processor will preferably read each stored menu selection, “T_INPUT_K” for the particular office computer in the office area 12 . It will be remembered that the value of the stored menu selection will be 1 if the comfort level selection was “TOO HOT”, 0 if the comfort level selection was “JUST RIGHT”, and −1 if the comfort level selection was “TOO COLD”. The processor will proceed to a step 46 and compute the value of a variable “T_CLUSTER_AVG”. The value of this variable is equal to the sum of the read “T_INPUTS” in step 44 . The processor will proceed to a step 48 and inquire as to whether the value of “T_CLUSTER_AVG” is greater than the value of a variable “T_AVG_HI_LIMIT”. It is to be understood that the value of “T_AVG_HI_LIMIT” will be predefined for the particular office building or even office area under review. In this regard, assuming that there are ten office computers in each office area of the office building, then the value of “T_AVG_HI_LIMIT” could be equal to 5. This would require that the net sum of T_INPUTs would have to be greater than 5 in step 48 in order for the processor to proceed to a step 50 . It is, of course, to be appreciated that the value of “T_AVG_HI_LIMIT” could be set lower so as to not require that so many stored menu selections be equal to 1. Referring to step 50 , in the event that “T_CLUSTER_AVG” is greater than “T_AVG_HI_LIMIT”, then the processor sets the variable “CLUSTER_N_AVG” equal to 1. The value of “N” in this variable will equal the current office area index value. This variable will therefore be an overall indication as to the comfort level in the office area indicated by the index value “N”. This overall indication would be “TOO HOT” out of step 50 .
[0019] Referring again to step 48 , in the event that “T_CLUSTER_AVG” is not greater than “T_AVG_HI_LIMIT”, then the processor will proceed along a no path to a step 52 . Referring to step 52 , the processor will inquire as to whether “T_CLUSTER_AVG” is less than the value of “T_AVG_LOW_LIMIT”. It is to be appreciated that the value of “T_AVG_LOW_LIMIT” will be set for all office areas in the office building or for the particular office area then under review. This value will again be set so as to require that the net sum of “T_INPUTS” is predominantly negative so as to indicate a predominance of “TOO COLD” having been selected from the menu 30 on each screen of an office computer within the office area indicated by the index “N”. For instance, this variable may be set equal to −3, −4, or even −5 for an office area including ten separate office computers. In the event that “T_CLUSTER_AVG” is less than the value of “T_AVG_LO_LIMIT”, then the processor will proceed from step 52 to a step 54 and set “CLUSTER_N_AVG” equal to −1. This will be an overall indication that the office area having an office area index equal to the current value of N is too cold.
[0020] Referring again to step 52 , in the event that “T_CLUSTER_AVG” is not less than “T_AVG_LO_LIMIT”, then the processor will proceed to step 56 and set “CLUSTER_N_AVG” equal to 0, wherein the value of “N” will be the particular value of the office area index. This will be an overall indication that the temperature level is “JUST RIGHT” for the particular office area.
[0021] The processor proceeds from either step 50 , step 54 , or step 56 to a step 58 and inquires as to whether the office area index “N” is equal to “MAX_CLUSTER_INDEX”. The value of “MAX_CLUSTER_INDEX” will be equal to the highest value of the office area index identifying the last office area to be analyzed. In the event that the value of the office area index “N” is not equal to “MAX CLUSTER INDEX”, then the processor will proceed to a step 60 and increment the office area index “N” by one before returning to step 44 . It is to be understood that the processor within the network computer will again execute steps 44 - 58 so as to determine the overall indication of comfort for the office area indicated by the new value of office area index “N”. This will be stored in the new “CLUSTER_N_AVG”. The value of the office area index “N” in the variable “CLUSTER_N_AVG” will identify the particular office area to which the overall comfort level indication applies.
[0022] Referring again to step 58 , it will be understood that at some point, all office areas will have been analyzed and all overall comfort level indications will have been defined in respective values of “CLUSTER_N_AVG”. When this occurs, the processor will proceed to a step 62 and send all CLUSTER_N_AVGs for N=0 to N=MAX_CLUSTER to the HVAC system control 24 . The processor will proceed to step 64 and inquire as to whether the value of “TIMER_CLOCK” equals “MAX_TIME”. The value of “MAX_TIME” will be arbitrarily set for the particular office building or office area under examination. In either case, the “TIMER_CLOCK” must exceed the “MAX_TIME” in order for the processor to proceed back to step 42 and again begin to collect the comfort level selections that have been made and stored as “T_INPUT_K” for each office computer in the first office area having an office area index value of 1. The menu sections from all such office computers will again be analyzed and an overall comfort level indication for each particular office area will be defined in CLUSTER_N_AVG before proceeding to the next office area. When all such office areas have been analyzed, the overall comfort level indications for each office area will be forwarded to the HVAC control 24 again in step 62 .
[0023] Referring now to FIG. 5, an exemplary program or process is set forth that could be implemented in the HVAC system control 24 . The exemplary program could be used in response to the overall comfort level indications for each office area that are sent by the network computer 22 . The program or process begins with a processor within the HVAC system control implementing a step 70 wherein inquiries made as to whether all “CLUSTER_N_AVG” values have been received from the network computer 22 . When this occurs, the processor proceeds to step 72 and sets the office area index “N” equal to 1. The processor next reads “CLUSTER_N_AVG” for the current index value of “N”. The processor proceeds to step 76 and inquires as to whether the read “CLUSTER_N_AVG” of step 74 is equal to one. If it is, the processor will proceed to a step 78 .
[0024] Referring to step 78 , it will be assumed that the HVAC system 10 of FIG. 1 includes damper position controls for each office area within the office building. In such a system employing damper control, the processor will, in step 78 , increase a “CLUSTER_N_DAMPER_POSITION” by a predefined amount “Δ” for a cooling mode of operation of the HVAC system. On the other hand, the processor will decrease the same “CLUSTER_N_DAMPER_POSITION” by the incremental amount “Δ” for a heating mode. This will thereby provide more cool air to an office area that has indicated that the office area is too hot or it will decrease the amount of heated air provided in the event that the HVAC system is in a heating mode of operation. Referring again to step 76 , in the event that the overall comfort level indication for temperature in the particular office area is not equal to one, then the processor will proceed to step 80 and inquire as to whether “CLUSTER_N_AVG” is equal to −1. In at the event that it is, the processor will proceed along a yes path to step 82 and increase the value of “CLUSTER_N_DAMPER_POSITION” by the incremental amount “Δ” when in a heating mode or decrease this damper position variable by “Δ” for a cooling mode. This will have the effect of providing A more heated air for an office area that has an overall comfort level indication of being too cold during the heating mode or decreasing the amount of cooled air provided to the same location in the event that the HVAC system is in a cooling mode. The processor will proceed from having either increased or decreased the damper position variable in step 82 to a step 84 .
[0025] Referring to step 84 , it is to be appreciated that this step will be encountered after execution of either step 78 , step 82 or step 80 . Referring to step 80 the processor proceeds along the no-path out of step 80 when the overall comfort level indication for temperature for the particular office area is neither equal to 1 or −1. The overall comfort level indication for temperature will in this case be 0 indicating that the overall comfort level is just right. The processor will, in step 80 , inquire as to whether the value of the office area index “N” equals the value of “MAX_CLUSTER_INDEX”. It will be remembered that the value of “MAX_CLUSTER_INDEX” is equal to the highest value of the office area index. This would identify the last office area having an overall comfort level value to be processed. In the event that the processor has not processed the last overall comfort level value for the last office area, the processor will proceed along the no-path and increment the office area index “N” by one in a step 86 . The processor will proceed back to step 74 and read the “CLUSTER_N_AVG” for the office area having the newly defined office area index value. The overall comfort level value for temperature for this particular office area will be analyzed and the damper position variables will be appropriately incremented or decremented as has been previously described. At some point the overall comfort level indications for all office area will have been processed again. At this point, the processor will proceed out of step 84 along the yes path back to step 70 . The processor will again await receipt of a new set of overall comfort level indications for the office areas before proceeding to analyze each such overall comfort level indication and again, set the damper positions in steps 72 through 86 .
[0026] Referring now to FIG. 6, an example of an alternative menu that could be displayed on each office computer is shown. The comfort control menu 90 is with respect to humidity. In this regard, the occupant of the room is invited to select between “TOO DRY”, “JUST RIGHT” and “TOO HUMID”. The occupant clicks on the ENTER icon 92 when the selection has been made. The network computer will analyze the comfort level values for each office computer regarding humidity in much the same manner as been heretofore described with respect to the comfort control for temperature in FIG. 2. The humidity for the particular office area will either be adjusted upwardly or downwardly or no change made to it depending on the overall comfort level indication for the particular office area. This can be done either by dedicated humidifiers in the air flow paths to the particular office areas or it could be done at the central location of the HVAC system. In the latter case, all comfort level indications as to humidity for all office areas would have to be analyzed before determining whether or not to adjust any centrally located humidifier. In this latter instance, if the overall humidity is to be raised, and one or more of the offices, in fact, indicated that they wanted less humidity, then the dampers could be controlled in conjunction with the new raised humidity level for office areas indicating that the comfort level for humidity was already too high.
[0027] It is to be appreciated from the above that a number of programs resident in processors within an office computer, a network computer, and an HVAC system control have been disclosed. Alterations, modifications and improvements to these various individual programs may readily occur to those skilled in the art. For instance, the particular comfort control menu may vary as to how it is displayed as well as how many particular comfort level selections may be made. Furthermore, the processor program executed by the network computer could compute the overall comfort level indications for each particular office area in a different manner. This could include summing all comfort level values provided by the office computers and dividing by the number of computers in the particular office area. This could thereafter be compared with an appropriate high and low limit for such a computed average before setting the particular overall comfort level indication for that particular office area. The network computer program could furthermore require several distinct samplings of the comfort levels from each office computer with resulting computations as to overall comfort level indications before arriving at a particular overall comfort level indication average that is to be used for that particular area. It is to be furthermore understood that the particular program implemented by an HVAC system control downstream of the network computer could vary considerably depending on the HVAC system that is to be controlled and the particular overall comfort level indication that is to be responded to. In this regard, an alternative to temperature comfort could be the humidity in each office area. Accordingly, the foregoing description of the particular programs in the preferred embodiment is by way of example only and the invention is to be limited by the following claims and equivalents thereto. | A data collection system allows occupants in one or more locations to provide indications as to their respective levels of comfort. The indications as to comfort level are preferably provided through personal computers in these locations. Each computer is programmed to display a menu of comfort level options that may be selected by the user of the computer. Each computer is operative to require that any selected comfort level be accompanied by a verification as to the user making the one or more selections. The verification preferably requires an entry of an identification that may be checked against a stored identification. Each computer is operative to timely provide the selections as to comfort level by a recognized user to a network computer. The network computer is operative to analyze the comfort level information from these computers and send one or more commands to an HVAC system providing conditioned air to the locations. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a projection-type display device, and more particularly to a projection-type display device in which a display body having a screen and a projector unit having a projector are mutually separable.
There is a type of projection-type display device in which a display body having a screen and a projector unit having a projector are separable from each other for purposes of repair and maintenance.
In such a projection-type display device, the projector unit has casters provided at the lower part. However, this device has a disadvantage that the projector unit cannot, be easily handled when separated from or received into the display body due to its large weight. In particular, the projector unit tends to collide with a lower cabinet of the display body when being received thereinto, thereby damaging the lower cabinet.
When the projector unit is separated from the display body and thereafter received into the display body, it is difficult to exactly locate the projector unit at the same position as it was prior to separation. Therefore, there would sometimes arise a undesirable change in the optical relationship between the projector unit and the display body. As a result, an image projected on the screen is deteriorated. Also, when the projection-type display device is moved to another place, the optical relationship between the projector unit and the display body would likewise change due to the difference in the floor state of the respective installing locations of the display body and the projector unit, so that an image projected on the screen is deteriorated. In such cases, the optical relationship should be readjusted. Adjusting the optical relationship requires quite delicate operations and a number of man-hours.
Further, although the projector unit must be inclined upon repairing and maintenance, this cannot easily be done because of the significant weight of the projector unit as mentioned hereinbefore. Therefore, it sometimes occurs that the casters provided at the lower part of the projector unit undesirably slide, damaging the flor surface or people when the projector unit is inclined.
It is therefore a first object of the present invention to provide a projection-type display device which is capable of easily separating the projector unit from the display body and which does not suffer optical change between the display body and the projector unit when both are mutually separated or when the projection-type display device is moved to another place.
It is a second object of the present invention to provide a projection-type display device which is capable of preventing the projector unit from skidding when being laid down so as not to injure or damage workers or the floor.
SUMMARY OF THE INVENTION
A projection-type display device according to the present invention comprises: a display body including an upper cabinet having a screen at the front portion thereof and a lower cabinet having a pair of side frames for supporting the upper cabinet; a projector unit including projectors and a mounting device on which the projectors are mounted movable in the forward/backward direction with respect to the lower cabinet; guide means for guiding the projector unit to a predetermined position in the display body when the projector unit is received into or separated from the display body; means for locating the projector unit at a predetermined position and securing together the projector unit and the display body to separate one of them from the floor surface; and means for supporting the other of the projector unit and the display body which is grounded on the floor surface at three portions.
In a first embodiment of the projection-type display device according to the present invention, the guide means comprises a pair of plate-like guide rails extending in the forward/backward direction on the lower cabinet of the display body and having a tapered forward portion; a plurality of rollers rotatable on the plate-like guide rails and mounted on the projector unit at a level where the projector unit is separated from the floor surface when the rollers rotate on the plate-like guide rails; brackets protruding laterally from the projector unit and having flanges for guiding the projector unit by engaging with outer side surfaces of the plate-like guide rails; and the locating means comprises through holes formed at predetermined positions on the brackets, screw holes formed at predetermined positions on the guide rails, and bolts to be passed through the through holes to be screwed into the screw holes.
In a second embodiment of the projection-type display device according to the present invention, the guide means comprises: a pair of ball groups arranged in the forward/backward direction and rotatably supported on the lower cabinet of the display body through perforated plate members; and brackets laterally extending from the projector unit and having flanges formed at outer edges for guiding the projector unit by engaging with outer surfaces of the plate members; and the locating means comprises through holes formed at predetermined positions on the brackets, screw holes formed at predetermined positions on the perforated plate members, and bolts to be passed through the through holes to be screwed into the screw holes.
In a third embodiment of the projection-type display device according to the present invention, the guide means comprises: a pair of flanged guide rails mounted on the lower cabinet of the display body, extending in the forward/backward direction, each of the guide rails having a front portion sloped in the direction of thickness and being widened toward a front end; and a plurality of rollers guided by the flanges of the flanged guide rails to rotate thereon, the rollers being rotatably installed on the projector unit at a height level where the projector unit is separated from the floor surface when the rollers rotate on the flanged guide rails; and the locating means comprises through holes formed at predetermined positions on the brackets extending laterally from the projector unit, screw holes formed at predetermined positions on the flanged guide rails, and bolts to be passed through the through holes to be screwed into the screw holes.
In a fourth embodiment of the projection-type display device according to the present invention, the guide means comprises: a pair of guide rails mounted on the lower cabinet of the display body, extending in the forward/backward direction and brackets extending laterally from the projector unit and having flanges formed at outer edges for guiding the projector unit by engaging with outer side surfaces of the guide rails; and the locating means comprises through holes formed at predetermined positions on the brackets, screw holes formed at predetermined positions on the guide rails, and bolts to be passed through the through holes to be screwed into the screw holes; whereby the display body is separated from the floor surface when the display body and the projector unit are joint together.
The projector unit preferably comprises means for preventing skid disposed at a fulcrum position for the projector unit when it is laid down and stood up.
Since the projection-type display device according to the invention comprises the guide means for guiding the projector unit to a predetermined position in the display body when the projector unit is received into the display body, it is possible to locate the projector unit in the predetermined position with respect to the display body without the projector unit being come into collision with the display body.
Further, the projection-type display device according to the present invention comprises the locating means for locating the projector unit at the predetermined position, securing together the projector unit with the display body, and separating one of them from the floor surface. Therefore, when the projector unit and the display body are joined together, the optical relationship between them will be necessarily determined. As a result, it becomes unnecessary to readjust the optical relationship therebetween when the projector unit is separated/received from/into the display body.
Furthermore, one of the projector unit and the display body which is grounded on the floor is supported at three points, so the projection-type display device do not receive any influence from change of floor surface state even when moved to another place and not to require the readjustment of the optical relationship therebetween.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic perspective view of a conventional projection-type display device in which a display body having a screen and a projector unit having a projector are mutually separable;
FIG. 2 is a schematic perspective view of a first embodiment of a projection-type display device according to the present invention;
FIG. 3 is a partial front view of the first embodiment of the present invention;
FIG. 4 is a partial cross-sectional front view taken along line IV--IV in FIG. 2 when the projector unit is received in the display body;
FIG. 5 is a bottom view of the first embodiment when the projector unit is received in the display body;
FIG. 6 is a schematic perspective view of a second embodiment of the projection-type display device according to the present invention;
FIG. 7 is a partial front view of the second embodiment of the present invention;
FIG. 8 is a schematic perspective view of a third embodiment of the projection-type display device according to the present invention;
FIG. 9 is a partial front view of the third embodiment of the present invention;
FIG. 10 is a cross-sectional front view of an essential part taken along line X--X in FIG. 8 when the projector unit is received in the display body.
FIG. 11 is a schematic perspective view of a fourth embodiment of the projection-type display device according to the present invention;
FIG. 12 is a cross-sectional front view of an essential part taken along line XII--XII in FIG. 11 when the projector unit is received in the display body;
FIG. 13 is a bottom view of the fourth embodiment when the projector unit is received in the display body; and
FIG. 14 is a schematic side view of the projector unit according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the projection-type display device according to the present invention will now be described with reference to FIG. 1 and FIGS. 2 through 5. The projection-type display device in the form of a cabinet comprises a display body 10 and a projector unit 20. The display body 10 includes an upper cabinet 11 and a lower cabinet 12, and a screen 13 is secured to the upper cabinet 11. The lower cabinet 12 has a pair of side frames 14, between which the projector unit 20 is removably received.
The projector unit 20 includes a mounting device 21 and a projector 23 mounted thereon. The mounting device 21 includes a chassis 22 and casters provided at the lower portion of the chassis 22 so as to be movable. The chassis 22 has handles 25 used when the projector unit 20 is moved.
As shown in FIG. 2, the chassis 22 of the mounting device 21 has rollers 26 extending laterally at its four corners, which are mounted rotatably in the forward/backward direction of the projector unit 20. Further, the chassis 22 is provided with brackets 27 laterally protruding at both its sides, and the bracket 27 has a flange 28 formed at an outer edge and extending downwardly. Through holes 29 are formed in position on the brackets 27.
The side frames 14 of the display body 10 have bases 15 extending in an inward direction of the display body 10. A pair of guide rails 16 (only one guide rail is shown in FIG. 2) for guiding the projector unit 10 by engaging with the flange 28 are provided on the upper part of the bases 15, extending in the forward/backward direction of the display body 10. A space between an outer side surface 16c of the guide rail and the flange 28 is formed to be smaller than that between the base 15 and the chassis 22 such that the chassis 22 of the projector unit 20 does not collide with the bases 15 of the display body 10 when the projector unit 20 is received in the display body 10. A front portion of the guide rail 16 has a slant portion 16a with a thickness gradually reduced toward a distal end, and a slant portion 16b with a width gradually reduced toward an inside of the display body (see FIGS. 2 and 3). An upper surface of the guide rail has screw holes 18 which alignes with the through holes 29 formed in the bracket 27 when the projector unit 20 is received at a predetermined position in the lower cabinet 12. A thickness of the guide rail 16 is designed to allow a space to be formed between the casters 24 of the projector unit 20 and the floor surface when the rollers 26 of the projector unit 20 rotate on the upper surfaces of the guide rails 16, and to allow the projector unit 20 to be set with respect to the display body 10 at a predetermined height.
Further, as shown in FIG. 5, the casters 19 formed at the lower part of the display body 10 are provided at three portions taking account of the weight balance of the projection-type display device.
With the above-explained structure, when the projector unit 20 is received in the display body 10, inner sides of the flanges 28 of the brackets of the projector unit 20 will firstly engage with the slant portions 16b of the guide rails of the display body 10 and subsequently with the outer side surfaces 16c of the guide rails 16, so that the projector unit 20 is guided to a substantially predetermined position in the width direction of the display body 10. On the other hand, the rollers 26 of the projector unit 20 will engage with the slant portions 16a of the guide rails 16, rotate on the slant portions 16a and further on the upper surfaces of the guide rails 16. At this time, the projector unit 20 becomes separated from the floor surface and is supported by the display body 10. As a result, the projector unit 20 is guided to a predetermined height relative to the display body 10.
Next, as shown in FIG. 4, the through holes 29 formed in the brackets 27 and the screw holes 18 formed on the upper surfaces of the guide rails 16 are aligned, and bolts 30 are passed through the through holes 29 and to be screwed into the screw holes 18, so that the projector unit 20 is located at a predetermined position with respect to the display body 10. Accordingly, it is not necessary to adjust the optical relationship between the display body 10 and the projector unit 20. In addition, since the display body 10 supporting the projector unit 20 is grounded at the three points, the optical state of the projection-type display device is not affected by the change of state of the floor surface. As a result, the optical relationship need not be adjusted even when the projection-type display device is moved to another place.
A second embodiment of the projection-type display device according to the present invention will now be described with reference to FIGS. 6 and 7, particularly focusing on its difference from the aforementioned first embodiment.
A projector unit 200 is the same as the projector unit 20 in the first embodiment, except that it lacks the rollers 26.
In this second embodiment, the guide rails 16 of the first embodiment is replaced by a pair of ball groups 101 arranged in the forward/backward direction of the display body 10 (only one ball group is shown in FIG. 6). Balls are rotatably held on the base 15 by a perforated plate member 102. When the projector unit 200 is received in the display body 100, the brackets 27 of the projector unit 200 move on the ball groups. In this case, the height of the balls are set such that a space can be formed between the casters 24 of the projector unit 200 and the floor surface and that the projector unit 200 is set at a predetermined height with respect to the display body 100. A space between an outer side surface 102b of the perforated plate member 102 and the flange 28 is set to be smaller than that between the base 15 and the chassis 22, such that the chassis 22 of the projector unit 200 does not collide with the bases 15 of the display body 100. A front portion of the perforated plate member 102 has a slant portion 102a with the width being gradually reduced toward the inside of the display body 100. An upper surface of the perforated plate member 102 has screw holes 18 aligned with the through holes 29 formed in the bracket 27 when the projector unit 200 is received in a predetermined position with respect to the display body 100.
With the aforementioned structure, when the projector unit 200 is received in the display body 100, inner sides of the flanges 28 of the brackets 27 of the projector unit 200 engage with the slant portions 102a of the perforated plate members 102 of the display body, and thereafter with outer side surfaces 102b of the perforated plate members 102, so that the projector unit 200 is guided to a substantially predetermined position in the width direction of the display body 100. On the other hand, the lower surfaces of the brackets 27 of the projector unit 200 engage with the balls, and move on the balls. At this time, the projector unit 200 is separated from the floor surface, and is supported by the display body 100. As a result, the projector unit 200 is guided to a predetermined height with respect to the display body 100.
Next, as shown in FIG. 4, the through holes 29 formed in the brackets 29 and the screw holes 18 formed in the upper surfaces of the perforated members 102 are aligned and the bolts 30 are screwed into the screw holes 18 via the through holes 29, so that the projector unit 200 is located at a predetermined position with respect to the display body 100. Therefore, there will be no need to adjust the optical relationship between the display body and the projector unit. Further, as shown in FIG. 5, because the casters 19 mounted on the lower portion of the display body 100 are installed at the three portions taking account of the weight balance of the projection-type display device, the projection-type display device is not affected from any change in the floor surface state.
A third embodiment of the projection-type display device according to the present invention will now be described with reference to the FIGS. 8, 9 and 10, particularly focusing on its difference from the first embodiment.
In this third embodiment, the brackets 27 of the projector unit 20 of the first embodiment are replaced by plate-type brackets 401, and the rests are the same as those of the first embodiment. The bracket 401 has through holes 29 in position.
Instead of the guide rails 16 in the first embodiment, a pair of flanged guide rails 301 extending in the forward/backward direction of the display body are provided (only one flanged guide rail is shown in FIG. 8). The flanged guide rail 301 has flanges 301b, 301c extending upwardly at both its sides. A space between the outer flange 301b of the flanged guide rail 301 and the rollers 26 is set to be smaller than that between the base 15 and the chassis 22 such that the chassis 22 of the projector unit 400 does not collide with the base 15 of the display body 300 when the projector unit 400 is received in the display body 300. A front portion of the flanged guide rail 301 has a slant portion 301a with a thickness being gradually smaller toward a distal end and a width being gradually wider toward the outward direction of the display body. An upper surface of the flanged guide rail 301 is formed with screw holes 18 which align with the through holes 29 formed in the bracket 401 when the projector unit 400 is received in a predetermined position in the display body 300. A thickness of the flanged guide rail 301 is set such that a space can be formed between the casters 24 of the projector unit 400 and the floor surface when the rollers 26 of the projector unit 400 rotate on the flanged guide rail 301 and that the projector unit 400 is set at a predetermined height with respect to the display body 300.
With the above structure, when the projector unit 400 is received in the display body 300, the rollers 26 of the projector unit 400 engage with the flanges 301b of the flanged guide rails 301 of the display body, so that the projector unit 400 is guided to a substantially predetermined position in the width direction of the display body 300. In addition, the rollers 26 of the projector unit 400 engage with the slant portions 301a of the flanged guide rails 301 to rotate on the slant portions 301a and further on the flanged guide rails 301. At this time, the projector unit 400 is separated from the floor surface, and supported by the display body 300. As a result, the projector unit 400 is guided to a predetermined height position with respect to the display body 300.
Next, as shown in FIG. 10, the through holes 29 formed in the brackets 401 and the screw holes 18 formed on the upper surfaces of the flanged guide rails 301 are aligned and the bolts 30 are screwed into the screw holes 18 through the through holes 29, so that the projector unit 400 is located at a predetermined position with respect to the display body 300. Therefore, there is no need to adjust the optical relationship between the display body and the projector unit. Furthermore, as the casters 19 provided at the lower portion of the display body 300 are installed at three portions taking account of the weight balance of the projection-type display device, the projection-type display device can be stably located without receiving influence from the floor surface.
A fourth embodiment of the projection-type display device according to the present invention will now be described with reference to FIGS. 11, 10 and 13, particularly focusing on its difference from the first embodiment.
A projector unit 600 is the same as the projector unit 20 in the first embodiment except that it lacks the rollers 26.
The display body 500 is provided with a pair of guide rails 501 extending in the forward/reward direction of the display body (only one guide rail 501 is shown in FIG. 11). A space between an outer side surface 501b of the guide rail 501 and the flange 28 is set to be smaller than that between the base 15 and the chassis 22 such that the chassis 22 of the projector unit 600 does not collide with the base 15 of the display body 500 when the projector unit 600 is received. A front portion of the guide rail 501a is tapered with a slant portion having a width being gradually reduced toward the inside of the display body. On an upper surface of the guide rail 501 formed are screw holes 18 which align with the through holes 29 formed in the bracket 27 when the projector unit 600 is received in a predetermined position in the display body 500. A thickness of the guide rail 501 is set such that a space is formed between the guide rail 501 and the flange 27 of the projector unit 600 when the projector unit 600 is received in the display body 500, and that, as shown in FIG. 12, the display body 500 is located with respect to the projector unit 600 at a predetermined height when the projector unit 600 and the display body 500 are joined together.
Further, the casters 24 are mounted at three portions in the lower portion of the projector unit 600 taking account of the weight balance of the projector display device as shown in FIG. 13.
With the above-mentioned structure, when the projector unit 600 is received in the display body 500, the inner sides of the flanges 28 of the brackets 27 of the projector unit 600 engage with the slant portions 501a of the guide rails 501 of the display body, and further with the outer side surfaces 501b of the guide rails 501, so that the projector unit 600 is guided at a substantially predetermined position in the width direction of the display body 500. Since there is formed the space between the guide rails 501 and the flanges 27, the projector unit 600 can be advanced into the display body 500.
As shown in FIG. 12, thereafter, the through holes 29 formed in the brackets 27 and the screw holes 18 formed in the upper surfaces of the guide rails 501 are aligned and the bolts 30 are screwed into the screw holes 18 through the through holes 29, so that the display body 500 is separated from the floor surface to be supported by the projector unit 600. Thus, the display body 500 is located at a predetermined position with respect to the projector unit 600. Accordingly, there is no need to adjust the optical relationship between the display body and the projector unit. In addition, as shown in FIG. 13, since the casters 24 are mounted at three portions in the lower portion of the projector 600 taking account of the weight balance of the projection-type display device, the projection-type display device is not affected from a change in the floor state.
As shown in FIG. 14, the projector unit of the above-explained embodiments has a skid-proof projection such as rubber provided at position which would become the fulcrum when the projector unit is laid down or stood up. As a result, the casters are prevented from skidding when the projector unit is laid down or stood up, thereby avoiding causing damage to the people or the floor surface. | A projection-type display device comprises: a display body including an upper cabinet having a screen at a front portion thereof and a lower cabinet having a pair of side frames for supporting the upper cabinet; a projector unit including projectors and mounting device on which the projectors are mounted movable in the forward/backward directions with respect to the lower cabinet; guide device for guiding the projector unit to a predetermined position in the display body when the projector unit is separated from or received into the display body; locating device for locating the projector unit at a predetermined position and securing together the projector unit and the display body to separate one of them from the floor surface; and a device for supporting the other of the projector unit and the display body is grounded on the floor surface, at three positions. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 61/495,118 filed Jun. 9, 2011.
BACKGROUND OF THE INVENTION
[0002] This invention relates to tools. More specifically, this invention relates to an all in one measuring tool.
[0003] Measuring tools such as squares, rulers, saw guides, miter squares, rafter squares and the like have been around for years that assist workmen in accomplishing different tasks. Each of these different devices has its own unique purpose to assist the work person in a variety of different projects including tiling, roofing, decking, and the like.
[0004] A problem exists in that there is such an abundance of different tools for different applications that purchasing each individual tool is expensive. In addition, by having multiple different tools to keep track of, tools are easily lost and cumbersome to carry. Further, oftentimes, a person will get to a worksite and realize that one of the many tools they intended to pack was left behind forcing them to leave the worksite and go back to retrieve the tool causing delays and frustrations.
[0005] Thus, it is a primary object of the present invention to provide a measuring device system that improves upon the state of the art.
[0006] Another object of the present invention is to provide a measuring device that takes the place of several independent devices.
[0007] Yet another object of the present invention is to provide a measuring device that serves multiple needs.
[0008] Another object of the present invention is to provide a measuring device that is cost effective.
[0009] Yet another object of the present invention is to provide a measuring device that reduces the potential for lost or misplaced tools.
[0010] These and other objects, features, or advantages of the present invention will become apparent from the specification and claims.
BRIEF SUMMARY OF THE INVENTION
[0011] A measuring device system that provides the functions of a plurality of different measuring tools. The system has, a triangular measurement member having printed indicia thereon and a first elongated slot extending along one side of the triangle and a second elongated slot extending along a second side of the triangle. An arcuate slot is connected to the second elongated slot. An elongated arm having a centrally located slot is adjustably connected to the first elongated slot and the second elongated slot or arcuate slot by connecting members. This system provides the advantage of performing a plurality of measurement functions, it replaces a plurality of tools, reduces the need for multiple tools and therefore improves efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a perspective view of a first embodiment of a measuring device.
[0013] FIG. 2 is a perspective view of a second embodiment of a measuring device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] The figures show a measuring device system 10 that provides the functions of a plurality of different measuring tools. The system 10 has a triangular measurement member 12 that in a preferred embodiment is made from a metal plate. The triangular member 12 generally is a right triangle with first measuring side 14 and second measuring side 16 with a hypotenuse side 18 extending therebetween. Each of the first measuring side 14 and second measuring side 16 has printed indicia 20 thereon at predetermined locations to present measurements along each side. Similarly, the hypotenuse side 18 has printed indicia 20 thereon that provide additional predetermined measurements corresponding to different angles. The term printed indicia 20 is not meant to be limiting and can include any form of visible indicia including painted text, stickers, indented text, raised text, holes, grooves, inscribing, or the like or any combination thereof. In one embodiment the first measuring side 16 and second measuring side 18 are the same length. Alternatively, the triangular measurement member 12 is a right triangle with one side at 9 inches or alternatively a rectangle.
[0015] Disposed through the triangular measurement member 12 and disposed adjacent to the first measuring side 14 is a first elongated slot 22 that extends longitudinally the length of the entire first measuring side 14 . Preferably the first elongated slot 22 extends in parallel spaced alignment with the first measuring side 14 in straight, un-curved, and square fashion. Adjacent the first elongated slot 22 is printed indicia 20 . This includes primary printed indicia 20 A positioned between the first measuring side 14 and the first elongated slot 22 which indicates length among other information. This also includes secondary printed indicia 20 B, which is positioned adjacent first elongated slot 22 on the side opposite from first measuring side 14 which indicates maximum and minimum step rise among other information.
[0016] Like the first elongated slot, disposed through the triangular measurement member 12 is a second elongated slot 24 which is positioned adjacent the second measuring side 16 of the triangle measurement member 12 . Preferably the second elongated slot 24 extends in parallel spaced alignment with the second measuring side 16 in straight, un-curved, and square fashion. In a preferred arrangement, the second elongated slot 24 only extends longitudinally partially along the second measurement side 16 a distance before terminating at its terminating point 26 . Alternatively, second elongated slot 24 extends the entire length of second measuring side 16 like first elongated slot 22 . At its termination point 26 , second elongated slot 24 converges at a pivot point with an arcuate slot 28 . Arcuate slot 28 extends from the termination point 26 of second elongated slot 24 adjacent the second measuring side 16 toward and along the hypotenuse side 18 . Preferably, arcuate slot 28 curves in arcuate fashion with its convex side towards the hypotenuse side 18 and its concave side towards first measuring side 14 ; alternatively it curves in the opposite direction.
[0017] Adjacent the second elongated slot 24 is printed indicia 20 . This includes primary printed indicia 20 C positioned between the second measuring side 16 and the second elongated slot 24 which indicates length, among other information. This also includes secondary printed indicia 20 D which is positioned adjacent second elongated slot 24 on the side opposite from second measuring side 16 regarding minimum tread and maximum tread regarding a depth measurement, among other information. Meanwhile, adjacent either side of the arcuate slot 28 is printed indicia 20 E at predetermined measurement locations that determine roof pitch, among other information.
[0018] First elongated arm 30 and second elongated arm 32 are movably attached to the triangle measurement member 12 . Preferably, first elongated arm 30 and second elongated arm 32 are identical to one another. Both the first elongated arm 30 and second elongated arm 32 have an elongated arm slot 34 extending the length of the arm 30 , 32 in straight and square parallel spaced alignment with the arm's exterior edges. Preferably arm slots 34 run the length of the elongated arm 30 , 32 in a centered position. Printed indicia 20 F is positioned on either side adjacent the arm slot 34 at predetermined locations representing measurements, among other information. Each of the first and second arms 30 , 32 are movably connected to the triangle measurement member 12 via first connection member 36 and second connection member 38 that have adjustable heads 40 secured to elongated stems 42 with threaded portions that mesh with nut elements 44 positioned opposite adjustable heads 40 .
[0019] When put together the first elongated arm 30 is placed on a top surface 46 of the triangle measurement member 12 and the second elongated arm 32 is placed on a bottom surface 48 of the triangle member 12 . Preferably, nut portions 44 do not protrude past the surface of the second elongated arm 32 so that the bottom surface 48 is flat, flush and smooth and devoid of any protrusion. The stem 42 of the first connection member 36 is then disposed through the first elongated slot 22 and then through the elongated arm slot 30 of the second elongated arm 32 and then nut portion 44 is connected to the end of elongated stem 42 opposite adjustable head 40 to lock the pieces together. Similarly, stem 42 of the second connection member 38 is then disposed through the second elongated slot 24 or through the arcuate slot 28 and then through the elongated arm slot 30 of the second elongated arm 32 and then nut portion 44 is connected to the end of elongated stem 42 opposite adjustable head 40 to lock the pieces together. The nut elements 44 and/or adjustable heads 40 are twisted in a first direction to adjustably compress together the first and second arms 30 , 32 against the triangle measurement member 12 , or alternatively are twisted in an opposite second direction to loosen the arms 30 , 32 .
[0020] In operation, the first elongated arm 30 can be used as a ruler, marking gauge, or depth gauge as a result of sliding the elongated arm 30 laterally along the triangle member 12 along the first and second elongated slots 22 , 24 . When in place the first and second connection members 36 , 38 can then be tightened to prevent movement between the triangle measurement member 12 and the first and second elongated arms 30 , 32 .
[0021] Alternatively, the second connection member 38 can be placed in the pivot point/termination point 26 between the second elongated slot 24 of the second measuring side 16 and the arcuate slot 28 at which point it is tightened. Then the first connection member 36 can move within the first elongated slot 22 of the first measuring side 14 to provide multiple angles to present a stair gauge.
[0022] Alternatively, the second connection member 38 can be placed in the arcuate slot 28 adjacent the second side 16 and secured in place while the first connection member 36 is in the first elongated slot 22 to present a roof pitch gauge that can present different roof pitches.
[0023] One skilled in the art will also appreciate that the triangle measurement member 12 itself can operate as a miter square and a rafter square. Meanwhile, the second elongated arm 32 can be utilized as a 90 degree to 50 degree saw guide. Thus, a plurality of functions and tools are incorporated into this single system.
[0024] In an alternative embodiment a rectangular member 100 having first elongated side 102 and a second elongated side 104 in parallel spaced alignment and shorter parallel top and bottom sides 106 , 108 connect the first and second elongated sides 102 , 104 to form the rectangle 100 . Along the top short side 106 printed indicia 110 A with predetermined lengths is presented to act as a ruler. A first elongated slot 112 adjacent and extending longitudinally the length of an elongated side 102 , 104 is presented with a secondary slot 114 running perpendicular to the first elongated slot 112 and extending therefrom at an intersection between the first elongated slot 112 and the second elongated slot 114 that occurs preferably at a right angle.
[0025] The rectangular member 100 also has a rectangular opening 116 disposed therethrough of size and shape of an electrical outlet. An L-shaped arm 118 is presented having an elongated slot 120 extending longitudinally therein with marked indicia 110 B at predetermined locations on either side of the slot 120 . First and second connection members 122 having heads 124 , stems 126 and nut elements 128 as discussed above are disposed through the slot 120 of the L-shaped member 118 and the elongated slot 112 , 114 of the rectangular member 100 to connect the L-shaped member 118 to the rectangular member 100 . As a result of the rectangular member 100 having a T-shaped slotting 112 , 114 the L-shaped member can provide 360 degrees of positioning and measurement.
[0026] Similar to the triangle measurement member 10 embodiment, in operation the first and second connection members 122 move within the elongated slot 120 of the L-shaped member 118 , the elongated slot 112 of the first side 102 of the rectangular member 100 and the perpendicular slot 114 in order to move the L-shaped member 118 in relation to the rectangular member 100 . Specifically, when the first and second connection members 122 are both within the first elongated slot 112 the L-shaped member 118 acts as a caliper providing needed measurements between the L-shaped arm 118 and the bottom side 108 (or top side 106 ).
[0027] Alternatively, when a first connection member 122 is in the first elongated slot 112 and the second connection member 122 is in the perpendicular slot 114 , an angled measurement is provided wherein an indicia 110 C is on the top surface 130 of rectangular member 100 indicating where a 45 degree angle (or any other angle) is presented. When the first and second connecting members are both within the perpendicular slot 114 , again indicia is on the rectangular member 100 on either side of the L-shaped member 118 indicating that a 90 degree angle is presented and the system may be used as a traditional miter square.
[0028] In addition, as a result of the rectangular opening 116 the rectangular member can be placed around an outlet so that additional measurements can be presented when doing jobs such as tiling where such obstructions are presented. Thus, one does not have to remove the outlet cover in order to present proper measuring.
[0029] Thus presented are multiple systems that utilize a combination of slots and movable connection members in order to provide multiple functions of a plurality of different measurement tools. Thus, only a single tool has to be brought to a worksite eliminating the chance that a tool is forgotten and left behind. In addition, only a single system has to be purchased thus saving cost for a work person and additionally because tools do not have to be switched out, time is also saved. Thus, the present device has overcome the deficiencies in the art. | A measuring device system that provides the functions of a plurality of different measuring tools. The system has a triangular measurement member having printed indicia thereon and a first elongated slot extending along one side of the triangle and a second elongated slot extending along a second side of the triangle. An arcuate slot is connected to the second elongated slot. An elongated arm having a centrally located slot is adjustably connected to the first elongated slot and the second elongated slot or arcuate slot by connecting members. This system provides the advantage of performing a plurality of measurement functions, it replaces a plurality of tools, reduces the need for multiple tools and therefore improves efficiency. | 4 |
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to a building layout which includes a restaurant combined with artist functional areas for use by artists in the creation and display of their artistic works. More particularly, the present invention relates to a novel space utilization whereby an area is provided for use by artists in creating and displaying their various artistic efforts and whereby, in addition, the artist work/exhibit area is coordinated with a restaurant, with various service areas and dining areas for use by restaurant patrons as well as by the artists themselves.
Previous building structures which provide for diversity of use have included arrangements such as described in U.S. Pat. Nos. 3,778,911; 3,839,833; and 1,486,524. U.S. Pat. No. 3,778,911 relates to a classroom facility, including a first area for a learning devices center, and a second area for use in teaching psycho-motor activities. U.S. Pat. No. 3,839,833 relates to a combination multiple residential apartment and service area building. U.S. Pat. No. 1,486,524 is concerned with a music store configuration which includes both a concert room and a musical instrument sales area. Other related configurations are described in U.S. Pat. Nos. 2,858,579; 3,378,963; 3,803,778; 3,992,824; and 4,041,661.
By the present invention, there is provided an improved enclosed building structure for use as a combined restaurant facility and artist work/exhibit area. The present invention is particularly advantageous for use by persons who are using the artist work/exhibit area, either as artists or patrons of the arts, and who then wish to utilize dining facilities in a nearby area. The present invention provides a building structure which includes artist work/exhibit areas and an integral restaurant having food and drink preparation and service areas as well as dining areas. Included in the structure are the ancillary spaces for the artist work/exhibit areas, such as lounge, lavatory and locker areas. In addition, ancillary spaces for the restaurant are provided, including a waiting area for diners, lounges and restrooms, coat rooms, cashier's spaces and the like. The present construction results in a high degree of efficiency, with maximum utilization of the area involved and with cooperation between the artist work/exhibit areas and the restaurant areas. Provision is also made for maximum observation by restaurant diners of the artist exhibit and work areas, in order to contribute to the decor of the restaurant and also to enhance restaurant sales as well as sales of the artists' products, such as paintings, sculptures and the like. In addition, the present invention provides for efficient and easy movement of diners and artists between the artist work/exhibit area and the restaurant areas.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will be more fully understood from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is an overall schematic layout in plan view, including FIGS. 1A and 1B, showing the first or main floor of the combined restaurant and artist work/exhibit area of the present invention;
FIG. 2 is an overall schematic layout in plan view, including FIGS. 2A and 2B, showing the second floor of the combined restaurant and artist work/exhibit area of the present invention; and
FIG. 3 is a front elevation of the combined restaurant and artist work/exhibit area of FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment of the present invention as illustrated in FIGS. 1 through 3, there is shown the combined facility 10, which includes, on the first floor thereof, the dining area 11, the artist work and exhibit area 12, the service area 13 for the dining area and the general service area 14 for the facility 10. The facility 10 is constructed by the use of common building materials and components and the construction procedures are well known in the art.
The main dining area 11 is in the form of a landscaped courtyard, enclosed by walls 19. The dining area 11 includes a plurality of tables 15, the upper horizontal surfaces of which are each in the shape of an artist's palette. The palette colors 16 are painted or otherwise set onto the table 15 surfaces to indicate the seating positions around each table 15. Any suitable base (not shown) may be provided for the tables 15 which will result in stability of the tables 15 and allow comfortable seating around the tables 15. Various sizes of tables 15 with various numbers of seating positions 16 may be employed. The palette shape of the tables 15, with the indentation 17 which projects inwardly toward the center of tables 15, provides ease of access for service by a waiter or waitress from the inner portion of the indentation 17. Chairs (not shown) are positioned around the periphery of the tables 15 to correspond with the palette colors 16. The chair cushions are preferably of the same color as the adjacent palette color 16.
At the rear of the main dining area 11 is a stairway 18 of two stairs or so, leading up to an artist work/exhibit area 12 which is slightly elevated with respect to the dining area 11. A similar stairway 18 is located at the opposite end of the area 12. As shown in FIG. 1, the area 12 is provided with a series of separate booths or studios for each of various art disciplines, including, for example, individual studios for acrylics 21, watercolor 22, graphics 23 and non-clay sculpture 24 arranged along one outer wall 31 of the facility, and studios for photography 25, pastels 26, oil painting 27 and clay sculpture 28 arranged along the adjacent outer wall 32. The barrier between the main dining area 11 and the artist work/exhibit area 12 is provided by a series of arrangements 61 containing two seats and one table, which extend continuously along the boundary between areas 11 and 12 and thus provide a barrier of a height equal to the backs of the seats in the arrangements 61. At the front of the area 12 there are located a series of seats 62.
In the construction of studios 27 and 28, a glass partition 29 is provided to form the front wall, thus facilitating the viewing of work and exhibits in these studios 27 and 28 while preventing the viewers from coming into contact with the dust and odors which are often present in work areas devoted to these art disciplines. Standard wall partitions 33 may be employed to provide the remaining walls for these studios 27, 28 and a door 50 is located to the rear of studio 28. Vent fans 53 are also advantageously located in the ceilings of these studios 27, 28 to provide for air circulation and removal of odors and dust.
The photography studio 25 is constructed as an enclosed room by the use of wall partitions 33 with glass partition 29 forming the front wall. A dark room 30 is located adjacent the studio 25 and doors 51 and 52 are provided for entry to studio 25 and for passage between the studio 25 and the darkroom 30.
The completely enclosed studios 25, 27 and 28, along with vent fans 53 in studio 27, 28 are necessary to provide a clean air environment, particularly in the vicinity of the dining patrons.
Each of the studios 21 through 24 and 26 may be constructed by the use of wall partitions 33 extending at right angles to the respective outer wall 31, 32. The partitions 33 along with a portion of the respective outer wall 31, 32 serve as a support and background for the paintings and other works which are attached thereto for exhibit. The work area 34 in each of the studios is an area which is set apart from the remainder of the studio, such as by elevating or depressing the floor area 34 relative to the remainder of the floor. The patrons viewing the exhibits are then free to walk between the work area 34 and the walls 31, 33.
On the side of the facility 10 opposite to wall 31 there are positioned a plurality of serving bars 40 for use by the waiters in serving the dining patrons. The serving bars 40 are preferably arranged in a row along wall 41 opposite to wall 31 and each bar 40 is generally rectangular in shape with the longitudinal axis of the rectangle being parallel to the wall 41. The floor area 47 adjacent the serving bars 40 is slightly elevated above the main dining area 11, and is reached by one of the stairways 48 of two or so stairs.
Each bar 40 is provided with an interior rectangular shaped work space 42. A portion 43 of the bar surface is hinged on one side in a conventional manner to allow persons working in the interior space 42 to lift said portion 43 and thus pass freely into or out of the work space 42. A table 44 with food preparation surface and a sink 45 with running water are located in the interior space 42 of each serving bar 40. A plurality of stools 46 are positioned around the periphery of the bars 40. The serving bars 40 are set up to provide order pick-up for any of various foods and drinks to be served to the dining customers.
Located on the floor of the main dining area 11 adjacent to the serving bar 40 area are a plurality of serving carts 49 which may be stationary or mobile. These carts 49 will allow quick service by the waiters of items such as soups, canapes and the like and also mobile service of items such as desserts and coffees of various types. The carts 49 may be concealed behind planter boxes 60 of flowers to provide a neat appearance for the area. A similar arrangement of planter 60 and serving carts 49 is located at the rear of the main dining area 11.
In the lower right portion of FIG. 1, there are shown some of the ancillary spaces, including a passageway 63 and exit 64, an elevator 65 to the second floor, a storage room 66 for items such as art supplies and display equipment, an employees lounge and dressing room 67, and ladies' 68 and men's 69 rest rooms.
In the upper right portion of FIG. 1, there are shown a passageway 70 and exit 71, an elevator 72 to the second floor, and a series of the lockers 73 for use by the artists.
In the upper left portion of FIG. 1, there are shown an area 74 for sculpture display, an artists laundry and lavatory 75, a restroom 76 for employees, a kitchen office 77 and a service elevator 78 to the second floor. A ramp 79 up to the elevated floor area 12 is also provided. Service utensils may be stored in the area 80. A seating area 81 is provided for employees and a short flight 82 of two or so stairs provides entry into the rest room 76. Also located in this area is the "chef's corner", with preparation area 83, a dumb waiter 84 to the second floor, and a walk-in refrigerator 85. A counter 86 is provided adjacent the preparation area 83 for pick-up of food orders. An exit 87 is located adjacent the refrigerator area 85 in the serving area 13. A similar exit 88 is located at the lower left of FIG. 1, also in the serving area 13.
Also located on the first floor, as shown in the lower left portion of FIG. 1, are an elevator 89 to the second floor, men's 90 and ladies' 91 rest rooms, a supply room 92 and an office 93 for the management.
In the lower center portion of FIG. 1, there are shown the entrance 94 and exit 95 to the facility 10, with seats 96 located along one side of the exit passage 97 and with a waiting area 98, including seats and a palette-shaped table, adjacent to the entrance 94. Ancillary spaces include a music and audio control area 99, an area 100 for valuables, cloak rooms 101 and 102 and a cashier area 103. A list of exhibitors is posted on a bulletin board 104 in the vicinity of the entrance way and a piano bar 105, with seats 106 located around the periphery thereof, is located in the front portion of the main dining area 11.
In FIGS. 1 and 3 there are shown the exhibit preview window booths 107 which extend outwardly from the front of the building on both sides and in the center area thereof. These window booths are for the purpose of providing a preview exhibit from various art media, with one window booth 107 being devoted to photography, for example, while other booths 107 are employed to exhibit acrylics, watercolors, sculpture and the like.
In FIG. 2 there is shown a schematic floor plan of the second floor, which is reached from the first floor by the various elevators previously mentioned in regard to the description of the first floor. Thus the elevators 65, 72, 78 and 89, as well as dumb waiter 84, all provide service from the first floor. It should be pointed out that stairs may be employed between floors rather than elevators in one or more of these elevator locations, depending on personal preference and also the need to comply with local regulations.
It is the purpose of the second floor layout to provide an area for performance of other arts in addition to those described in connection with the first floor layout. Thus, for example, areas are provided for presentations of instrumental and vocal music, acting, poetry, dance, comedy and drama productions. These presentations may be scheduled at different times and in different areas as desired.
The second floor layout is arranged on four levels, with successive levels being slightly elevated or depressed relative to adjacent levels by a height equal to approximately two stairs. Located on the first or lowest level 109 of the second floor is a dance floor 110 of generally rectangular shape, with the long axis extending from front to back and having a plurality of palette-shaped tables 111 of the type described in connection with the first floor located around the periphery of the dance floor 110 at the front and along the sides thereof, as shown in FIG. 2. Stages 112 and 113 are located at the rear of the dance floor 110 and an orchestra level 114 is elevated above the stages 112, 113 at the fourth level of the second floor. The orchestra level 114 is reached from the rear and side, as described hereinafter. At the front end of the dance floor 110 a flight 115 of two stairs leads up to the second level 116. Similar flights 115 are located on both sides of the first level 109 at the rear thereof and these flights 115 also lead up to the second level 116.
The second level 116 extends around the first level 109 on three sides and is separated therefrom by a wall 117 of a height equal to the height of the flight 115 of stairs. The second level 116 is primarily employed as a service area for serving diners at the tables 111 on the first level 109. Stationary service carts 118 are provided for this purpose along both sides of the second level 116. At these carts 118 there are available such items as various cheeses, coffees, canapes and consommes, with individual carts being generally devoted to one of such items. Seats 119 are located along the sides of the second level for use by the waiters when they are not occupied with serving. The backs of such seats should face toward the dining tables 111 so that the seated waiters are obscured from the view of the dining patrons and those on the dance floor. Along the front area of the second level 116 there are located service booths 120 for use by the waiters and bus boys.
In the upper right portion of FIG. 2, there are shown some of the ancillary spaces on the second level 116, including a passageway 121 which extends from the vertical wall 125 defining the right side of the stage 113 and orchestra area 114 in an L-shaped configuration to an emergency exit 122 at the rear of the building. Seating 123 and service 124 areas are located on the sides of the passageway 121. To the right of the passageway 121 are located successive doors 126, 127, 128 leading, respectively, to an artists' locker room 129 with lockers 130, an elevator 72 to the first floor, and a space 131 which may be used as an artists rest and dressing area, or for storage. Between the passageway 121 and the orchestra area 114 are located a door 132 leading to a cashier's offices 133, 134 with connecting doors 135, 136 leading back to the passageway 121 adjacent the exit 122. A safe 137 may be located in the office 133. At the end of the passage 121 adjacent the stage 113 there is located a door 138 connecting to a passageway 139 which extends to a flight of four stairs 141 leading up to the orchestra area 114 which is on the fourth level 142. Adjacent to the passage 139 on the right side thereof are a musicians locker room 143 with lockers 144 and a lounge area 145 with seating 146.
In the upper left portion of FIG. 2, there are shown additional ancillary spaces on the second level 116, including a passageway 150 which extends directly to the rear of the second level serving area to the left side of the dance floor 110. The passage 150 leads to an emergency exit 154 at the rear of the building. A seating area 151 is located to the right of the passage 150 across from the stairs 115. Also on the right side of the passage 150 are a door 152 leading to the elevator 78 and a door 153 leading to a restroom 155. A group of seats 156 are located between the doors 152 and 153. A restroom 157 for musicians and artists is also located adjacent restroom 155, with stairs 158 leading to the orchestra area 114. The orchestra area 114 is provided with wings 159, 160 on the right and left side, respectively, as viewed from the audience, and the left wing 160 serves as a make-up wing, with a bench 161 and sink 162 provided for this purpose.
On the left side of the passageway 150 there is located a counter 170 for order pick-up and a door 171 leading to a food preparation area 172, with table 173, walk-in refrigerator 174, and a dumb waiter 84 to the first floor. A work counter 175 extends around the interior of the walls of the preparation space 172.
In the lower right portion of FIG. 2, there is shown the extension of the second level 116 as a passageway 180 leading to an emergency exit 181 from the right side of the building. On the right side of passageway 180 there are located doors 182, 183, 184 and 185 leading, respectively, to a ladies' room 186, men's room 187, a storage room 188 and the elevator 65.
In the lower left portion of FIG. 2, there is shown a door 189 leading from the service area of the second level 116 to an apartment 190 to be used by a visiting professor or other person as living quarters. Included in the apartment 190 are a convertible living room 191 and a kitchen 192, with awning 193. The kitchen 192 includes a stove 194 and refrigerator 195. Beyond the kitchen 192 there is located a bathroom 196. Adjacent the front door 189 of the apartment is a large walk-in closet 197 which is entered through door 198. A seating area 199 is located across from the door 189 in the service area. The living room 191 is provided with a double door arrangement 200 leading to a balcony 201 which projects out from the front wall 202 of the facility 10. The balcony 201 is also shown in FIG. 3. A false balcony 203 is constructed at the opposite end of the front of the facility 10, and attached to the front wall 202 adjacent the men's room 187 and ladies' room 186, as shown in FIGS. 2 and 3.
The second floor also includes a third level 204, including three portions 204a, 204b and 204c thereof, located at the front and left and right sides, respectively, of the second floor, as shown in FIG. 2. The front portion 204a is located between the outer front wall 202 and the second level 116 and is reached from the second level 116 via either of two sets of two stairs 205 located at either end of the third level 204a. Level 204a serves as a dining area, with a plurality of palette-shaped tables 111, along with chairs therefor, being located on the level 204a. At the center of the front wall 202 of area 204a, there is provided a balcony 205 which is built into the wall 202, and with a two stair 206 step-down to the balcony level, thus placing balcony 205 on the same level as balconies 201 and 203.
Third level area 204c on the right side of the second floor is located between the service second level 116 to the right of the dance floor 110 and the outer wall 31 on the right side of the facility 10. This area 204c is also reached from the second level 116 by two sets 208 of two stairs located at either end of the area 204c. Area 204c is also provided with a plurality of palette-shaped dining tables 111, with chairs, to allow area 204c to function as a dining area.
Third level area 204b on the left side of the second floor is located between the service second level 116 to the left of the dance floor 110 and the outer wall 41 on the left side of the facility 10. This area 204b is reached from the second level 116 by two sets 210 of two stairs located at either end of the area 204b. Area 204b is provided with a plurality of serving bars 40 similar to the bars 40 which are employed on the first floor. At the upper end of area 204b there are located a bar 207 and a service area 209. Emergency exits 211 and 212 are located at the upper and lower ends of area 204b. Also at the lower end of area 204 there are located a ladies' room 213 and a men's room 214, and a door 215 leading to the elevator 89.
The stairs which are, in general, employed in groups of two to define the various levels, may be of any standard height, such as about 8 inches. The distance between the first level of the first floor and the first level of the second floor may be of any convenient height, such as about 16 feet.
In FIG. 3 there are shown awnings 220 of various sizes which may be secured to the front wall 202 of the building structure and extend out over the window booths 107 and also over the balconies 201, 203 and 205. Various decorative signs (not shown) such as, for example, signs displaying theatrical masks, a dance team and a musical staff, may be attached to the outer front wall 202 over the balconies at the front of the building. In addition, a sign (not shown) stating the name of the club or facility 10 may be attached to the outer front wall 202. Possible locations for such decorations and signs are shown as item 221 in FIG. 2. The facility 10 is provided with a roof 222 which may be of any suitable construction, and with decorative features as desired.
The use of various levels for both the first and second floor is advantageous in allowing maximum viewing of artist exhibits and stage presentations throughout the facility 10. In addition, the use of various levels facilitates movement of people through the facility 10.
Unless otherwise stated, the various rooms and floor areas discussed herein are constructed in accordance with conventional construction practices so that, for example, a room will be understood to include floor, ceiling and walls of a conventional nature. Similarly, where a room is designated for a specific purpose, such as a men's or ladies' restroom, it will be understood that such a room will include those components, of a conventional nature, which will allow the room to fulfill such purpose. Furthermore, the building structure itself is of a conventional nature and may be of any suitable building materials which will provide a building of durable construction for the intended purpose as described herein.
It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the forms hereinbefore described being merely preferred embodiments thereof. | A coordinated building layout which includes a restaurant and artist work/exhibit area is disclosed. The cooperation between the restaurant area and the artist work/exhibit area results in maximum efficiency and space utilization. The present system enables accommodation of a wide variety of art disciplines, including the performing arts, while contributing to enjoyment of the arts by the dining patrons of the restaurant. | 4 |
TECHNICAL FIELD
[0001] The present invention relates in general to data processing systems, and in particular, to a device for controlling the time of actuation of a spring which may be incorporated, for example, in a disposable safety syringe or catheter.
BACKGROUND INFORMATION
[0002] Springs are commonly used as a power source for the actuation of an auxiliary component or device. However, springs have one characteristic which is unattractive in many applications. The amount of force which is generated by the spring when it is moved between stressed and free states is a largely linear function of the amount by which the spring has been compressed or expanded from its free state. Accordingly, when the spring is released, the spring generates its maximum amount of force at the instant of release, and the force declines linearly as the spring recovers to its free state.
[0003] In many applications, this sudden acceleration is undesirable. For example, in U.S. Pat. No. 5,053,010, entitled “Safety Syringe with Retractable Needle,” issued Oct. 1, 1991, there is shown and disclosed an improved safety syringe with retractable needle which allows retraction of the needle into a hollow plunger by forward pressure on the plunger after fluid is driven from the syringe into the patient. The syringe includes a hollow plunger which is inserted into one end of a cylindrical barrel and a hollow needle attached to the other end of the barrel. Actuation of the plunger subsequent to injection of the fluid within the barrel into the patient will cause the compressive bias within a spring mechanism to be applied against a carrier for the shifting of the needle into the interior of the hollow plunger. If liquid, such as medicine, still is contained within the interior of the hollow needle during the retraction step, the sudden acceleration of the needle in a backward-like direction into the interior of the plunger may, depending upon on the amount, viscosity, temperature, pressure and other variables, cause or contribute to considerable quick ejection out of the open end of the needle of such fluid, resulting in spillage onto the patient, operator, or floor immediate the area of positioning of the syringe. A similar situation could occur when the device to be actuated by the spring biasing mechanism is provided in the form of a catheter. The present invention addresses the problems set forth above.
SUMMARY OF THE INVENTION
[0004] The present invention provides a device for delivering energy which is stored in a spring which is to be moved between stressed and free states. The “stressed” state may be either compressed or expanded position or state. “Free” state is that condition that the biasing spring is in subject to substantially complete activation and may also be compressed or expanded in that condition. Thus, the “stressed” state is that state of the biasing spring prior to actuation, while the “free” state is that condition of the biasing spring subsequent to a completion of actuation.
[0005] The device includes a housing having an inner cylindrical wall of a given diameter. A continuous length of compressible spring, preferably provided in a continuously coiled or spiraled length, is stored in the housing and is positionable therein and along at least a portion of the wall in one of the stressed and free states, with the spring having an outer surface of a given diameter which is disposed along the continuous length of the spring. Means are provided for selectively actuating movement of the spring from one of the stressed and free states to the other of the said states and within the housing. Dampening means are provided for controlling the rate of movement, or the time of the movement, of the spring between the states and the actuation of the auxiliary component.
[0006] The dampening means may preferably comprise an elongated collar which is operatively positionable relative to the housing and includes an inner wall along the entire elongate. The collar has first and second open ends through which the spring is disposed. The collar further defines a restricted diameter passageway therethrough with the diameter of the restricted passageway being less than the diameter of the outer surface of the spring, such that the outer surface of the coils of the spring frictionally engages the inner wall of the collar to delay movement of the spring therethrough.
[0007] The device of the present invention may be incorporated into a non-reusable retractable safety syringe. Such a syringe may be provided wherein a cylindrical barrel, having first and second barrel ends and an inner diameter wall, defines a chamber which further receives fluid, such as medicine. A plastic hollow plunger extends into the barrel through the first end and is moveable from an expandable position toward an expended position. A hollow needle is secured relative to the second end of the barrel and a spring component incorporating the dampening means of the present invention is initially compressed in stressed state to provide energy for moving the hollow needle interior of the barrel and within the plastic hollow plunger subsequent to the plunger being moved to the expended position.
[0008] The invention may also be utilized in a catheter in which a hollow needle may telescopically contract relative to an outer cylindrical housing subsequent to use.
[0009] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
[0011] [0011]FIG. 1 is a horizontal cross-sectional view of the device of the present invention, illustrating a compressed spring in its stressed state being moved through a dampening means luring operation;
[0012] [0012]FIG. 2 is a cross-sectional view of the collar component of the device of FIG. 1;
[0013] [0013]FIG. 3 is a view similar to that of FIG. 1, with a spring shown in expanded state actuating against the wall of an auxiliary component, with the spring shown in its free state;
[0014] [0014]FIG. 4 is a horizontal cross-sectional view of a safety syringe incorporating the device of the present invention;
[0015] [0015]FIG. 5 is an enlarged detail view of the device of the present invention shown in the safety syringe of FIG. 4;
[0016] [0016]FIG. 6 is a horizontal sectional view of an alternative preferred embodiment of the device shown in FIG. 5;
[0017] [0017]FIG. 7 is a view similar to that of FIG. 6, showing yet another alternative preferred embodiment of the present invention;
[0018] [0018]FIG. 8 is a horizontal cross-sectional view of a catheter incorporating the device of the present invention;
[0019] [0019]FIG. 9 is a horizontal sectional view, constituting an enlargement of a portion of the device shown in FIG. 8; and
[0020] [0020]FIG. 10 is an alternative preferred embodiment of the design of the device of the present invention as shown in FIGS. 8 and 9.
DETAILED DESCRIPTION
[0021] In the following description, numerous specific details are set forth such as specific word or byte lengths, etc. to provide a thorough understanding of the present invention. However, it will be obvious to those skilled in the art that the present invention may be practiced without such specific details. In other instances, well-known circuits have been shown in block diagram form in order not to obscure the present invention in unnecessary detail. For the most part, details concerning timing considerations and the like have been omitted in as much as such details are not necessary to obtain a complete understanding of the present invention and are within the skills of persons of ordinary skill in the relevant art.
[0022] Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
[0023] Now, with first reference to FIG. 1, there is shown the device 10 in horizontal, cross-sectional view. The device 10 includes an outer elongated cylindrical housing 100 having at one end thereof a closed end surface 102 and at the opposite end an opening 103 through which may be introduced during manufacture, a length of compressible spring 106 , typically made of a metallic or plastic substance sufficient to be moved from stressed to free states without breakage, and farther, which is capable of storing compressive energy therethrough. The spring 106 has a terminating first end 107 which is housed within the housing 100 against the closed end 102 .
[0024] As shown in FIG. 1, the spring 106 is positioned within the housing 100 in stressed state SS. The housing has a diameter indicated by line 105 . In the stressed state SS and within the housing 100 , the outer surface 109 of the spring 106 may, or may not, come into contact with the inner wall 104 of the housing 100 , but it there is contact, it is casual and not sufficient to interfere with spring actuation, as the housing 100 only serves to contain the spring, not interfere with its operation. The spring 106 has a second end 108 which typically will abut against an auxiliary component AC (FIG. 3) having an inner wall AC- 1 . The spring 106 may thus cause movement of the auxiliary component AC, or the housing 100 , depending upon component organization and a particular operation at hand.
[0025] A collar 110 is provided which, as shown, may-be of circular or similar shape, the particular shape of the collar 110 not being particularly critical to the present invention. The collar 110 has an opening 115 therethrough through which the spring 106 may pass. The collar 110 has first and second open ends 114 , 115 through which the coils or loops 106 A of the spring may pass during actuation.
[0026] Now with reference to FIG. 2, the spring 106 has an outside diameter 111 and the collar 110 has a restricted passageway 116 therethrough such that the diameter of the restricted passageway 116 is somewhat smaller than the spring outside diameter II I and, preferably, the housing diameter 105 (assuming that the collar 110 and the housing 111 are in lateral alignment, as shown in FIG. 1). As the spring moves from the position shown in FIG. 1 to the position shown in FIG. 3, it will now be appreciated that the coil s 106 A of the spring 106 must pass through the opening, or restricted passageway 116 and the collar 110 . The friction resulting between the contact of the coils 106 A and the inner wall 113 of the collar 110 will “meter” or dampen movement of the spring 106 therethrough, causing a time delay of the actuating force in the spring 106 . The difference in the diameter of the spring 106 and that afforded through the restricted passageway 116 and defined by the inner wall 113 thereof controls a rate of recovery of the spring 106 by requiring the coils or loops 106 A of 10 the spring 106 to wind its way through the orifice, metering means, or collar 110 .
[0027] It has been experimentally determined that, for instance, a compression spring with an outside diameter of 0.285 inches will recover almost instantaneously through a spring controlled orifice with a diameter equal to or larger than 0.285 inches. As the spring control orifice is reduced in relative diameter, the spring recovery rate declines and the recovery period increases. With an orifice diameter of 0.266 inches (a 7% occlusion) the recovery period of the spring increases to about ½second. With an orifice diameter of 0.242 inches (a 15% occlusion), the recovery period of the spring increases to almost 2 seconds. Thus, by controlling the orifice, the time required for the winding of the spring from stressed to free state may be dramatically extended, while not adversely affecting the compressive biased energy stored or to be stored in the spring.
[0028] Now with reference to FIG. 4, there is shown a non-reusable retractable safety syringe 300 incorporating the device 10 of the present invention. A cylindrical barrel 301 is provided which receives at a second open barrel end 303 a hollow plunger 307 . The cylindrical barrel 301 also has a first barrel open end 302 through which is projected a retractable hollow needle 309 which is biased towards telescopically contracted state relative to the barrel 301 and plunger 307 by means of a compressed spring 310 . The syringe 300 includes a chamber 305 therein for receipt of fluid which is ejected out of the open end 309 A of the needle 309 during operation. An elastomeric seal 306 is disposed on one end of the hollow plunger 307 for movements against a smooth inside diameter wall 304 of the cylindrical barrel 301 to eject liquid completely out of the spring 300 .
[0029] Now with reference to FIG. 5, the dampening means is shown as provided by means of a collar or doughnut 311 which is geometrically provided in the form of a half-circle having a first inner surface 311 A for contacting engagement of a first coil surface 310 A of a spring 310 , with one end 310 B of the spring 310 shouldered against a surface 312 A of a needle carrier 312 disposed around one end of a hollow needle 313 . The first surface 311 A of the collar 311 extends inwardly of the inner wall 314 of a companion housing member 315 to resist movements of the spring coils 310 A there across.
[0030] A similar design for a metering means is shown in FIG. 6 in which the collar 110 is provided with a “V”-shaped orifice 117 having angled surfaces 117 A and 117 B disposed approximately 45° offset from a center line 150 of a housing component (not shown).
[0031] Likewise, as shown in FIG. 7, the collar 110 may actually be angled or beveled surfaces inwardly disposed on the housing for the spring element.
[0032] Now referring to FIGS. 8, 9, and 10 , there is shown the incorporation of the present invention into a catheter 400 . The catheter 400 is typical of such devices, and it comprises a hollow cylindrical body 406 and a catheter body top 407 which may be secured to the body 406 by threads 407 A, or by other convenient means. A spring 403 is provided therein having one end resting against a needle carrier 401 with a collar 410 of the design shown in FIG. 5 shown in FIG. 5 being disposed on the housing 406 . A clamp 408 is disposed interiorly of the housing member 407 , and when the clamp is released, the needle assembly may retract into the catheter body as a result of the biased compressive stress forces contained within the spring being metered through the metering means 410 to shift the housing 401 for the needle 402 inwardly of the cylindrical housing 406 . A semi-permeable membrane 405 , of known construction, is provided. The clamping device 408 may be one of any number of known- devices, such as that shown in U. S. Pat. No. 5,501,675 to Erskine.
[0033] Although the invention has been described in terms of specified embodiments which are set forth in detail, it should be understood that this is by illustration only and that the invention is not necessarily limited thereto, since other alternative embodiments and operating techniques will become apparent to those skilled in the art in view of the disclosure. Accordingly, modifications are contemplated which can be made without departing from the spirit of the described invention.
[0034] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. | Timing of movements of a spring between a stressed and a free state is delayed by dampening the spring movement through incorporation of a component having a restricted access diameter whereby frictional contact of the spring through the component will prolong the time required to move the spring between states to enhance control of the spring actuation. | 0 |
TECHNICAL FIELD
[0001] The present invention relates generally to electrode-type glow discharge devices used in the field of thin film depositation, and more particularly to a method and apparatus for applying coatings by magnetron sputtering in which surface cleaning and material deposition are provided in a continuous process.
BACKGROUND OF THE INVENTION
[0002] Magnetron sputtering is a well-known technique for depositing thin coatings onto objects. Sputtering of the coating onto an object occurs by generating plasma over the surface of an emitter material in a low-pressure gas atmosphere. An electrical field accelerates ions from the plasma to bombard and eject atoms from the surface of the emitter. Once ejected, the atoms travel through the gas environment and impact the surface of a target object to be coated, bonding to the target object and forming a coating layer. During the deposition process, a high ratio of ion-to-neutral fluxes is desirable to produce a dense, hard film with a low stress.
[0003] Prior to bombarding the target to form the coating layer, however, the surface of the target object must be clean and free from impurities. Generally, surface cleaning is performed through the process of sputter cleaning, in which the surface of a target object is bombarded with ions generated by a magnetron. A high current density bombardment of the surface of the target object is desirable in order to ensure a clean surface, and along with the use of a high ratio of ion-to-neutral fluxes during the deposition process, will produce a high quality film.
[0004] Presently, there are two methods used to accomplish the surface cleaning. In the first, a separate system for the sputter-cleaning process may be used, where the plasma is generated proximate the surface of the target object, and then the surface is bombarded with ions from the plasma that are drawn to the substrate by a filament or and RF source. After the sputter-cleaning process is completed, the target object can be transferred into the coating system for film deposition. This method is inconvenient and does not guarantee a clean surface, since oxidation will occur during the interruption between sputter-cleaning and sputter-coating. In the second method, the same system may be used for sputter-cleaning and the film deposition process. Theoretically, a plasma can be generated by turning on the magnetron and applying a voltage to the target object. Ions can then be drawn to the surface of the target object with a bias voltage. If the bias voltage is sufficiently high, the ions will cause sputtering of the surface. When the bias voltage is reduced, the film deposition process may begin. This is a typical approach used in most magnetron sputtering systems. Although this approach appears, on the surface, to be simple and without interruption during the transition, it has significant shortcomings. In order to increase the sputter-cleaning rate to remove native oxides and prevent the surface from re-oxidation, the bias voltage and/or the current density must be increased. In addition, during the cleaning, film deposition should be avoided. However, with existing magnetron systems wherein the plasma is generated by the magnetron, during the cleaning process the filament material is also sputtered and unavoidably deposited onto the target object. Moreover, an increase in the magnetron power, which results in an increased current density, will not help because it also increases the emitter material ionization, resulting in an increased rate of film deposition on the surface of the target object. Although an increase in the substrate voltage would increase the bombardment rate, the magnetron must be operated to provide ions for bombardment, which necessarily would result in film deposition. This hinders the cleaning of the surface oxides, which exist on almost all metals. Also, with this method, when the film deposition process begins, to obtain a high ion flux, the magnetron power has to be increased. At the same time, the flux of neutrals sputtered from the emitter material becomes proportionally higher. As a result, the ion-to-neutral ratio remains nearly constant and endangers the quality fo the film. Therefore, a compromise must be made in which a low current density with a high bias voltage must be used in order to minimize film deposition.
[0005] In addition to the problems associated with current attempts to combine the sputter-cleaning and deposition processes, in many sputter coating apparatuses, the sputtering voltage is applied with respect to end plates residing substantially perpendicular to the surface to be coated. Because the strength of the magnetic field varies along the distance between the end plates (e.g. along the surface of the target object), the non-uniformity of the magnetic field can result in a non-uniform coating. This is particularly true in the case where the target object is elongated, requiring an increased distance between the end plates.
[0006] Therefore, a need exists in the art to provide an integral sputter-cleaning and film deposition mechanism wherein the current density can be as high as necessary to effectively support the sputter-cleaning process without causing the ionization of the emitter material that results in film deposition. A further need exists to provide a mechanism for generating a uniform electric field with respect to the surface of the target object to be coated such that the cleaning and deposition is uniform along the surface of the object coated.
[0007] The following references are provided for further reference regarding magnetron sputter deposition:
[0008] M. Minato and Y. Itoh, “Vacuum Characteristics of TiN Film Coated on the Surface of a Vacuum Duct,” Nucl. Instr. and Meth. In Phys. Res. , Vol. B 121, 1997, pp. 187-190.
[0009] S. Penfold and J. A. Thornton, U.S. Pat. No. 4,030,996, Jun. 21, 1997.
[0010] N. Hosokawa, T. Tsukada and T. Misumi, “Self-Sputtering Phenomena in High-Rate Coaxial Cylindrical Magnetron Sputtering,” J. Vac. Sci. Technol . Vol. 14, No. 1, 1977, pp. 143-146.
[0011] R. Wei, “Low-Energy, High-Current-Density Ion Implantation of Materials at Elevated Temperatures for Tribological Applications,” Surf. Coat. Technol. , Vol. 83, 1996, pp. 218-227.
[0012] J. N. Matossian, R. Wei, J. Vajo, G. Hunt, M. Gardos, G. Chambers, L. Soucy, D. Oliver, L. Jay, C. M. Tylor, G. Alderson, R. Komanduri and A. Perry, “Plasma-Enhanced, Magnetron-Sputtered Deposition (PMD) of Materials,” Surf. Coat. Technol. , Vol. 108-109, 1998, pp. 496-506.
SUMMARY OF THE INVENTION
[0013] The present invention is directed toward a new and different plasma enhanced coaxial magnetron sputtering system that is suitable for depositing a thin film of sputtered material onto a substrate. Unlike the prior art devices, the present invention utilizes two steps for depositing a thin film, instead of one.
[0014] The plasma enhanced coaxial magnetron (PECM) assembly consists of a cooling system, ring magnets, a cylindrical sputtering target material, electron emitter filaments, a cylindrical meshed anode, and power supplies. This assembly is placed in the center of a cylindrical substrate that is to be coated. Both the PECM assembly and the tube substrate are housed in a vacuum chamber. The operation of this apparatus is detailed in two steps: sputter cleaning without target material deposition and uniform sputter coatings of cylindrical substrate.
[0015] When the vacuum system is pumped down, typically to the low 10 −6 Torr range, a working gas (Ar) is introduced to the chamber to a pressure typically of a few milli-Torr. Then, an AC voltage V f is applied to the filaments to heat them up to a thermionic temperature (˜2000° C. for tungsten). Electrons are then generated. With the application of a DC voltage V d between the anode and the filaments, the electrons will migrate to the anode. Due to the strong magnetic field generated by the ring magnets, the electrons will experience many collisions with the gas before reaching the anode, resulting in high ionization of the gas, thereby producing an intense plasma. A negative voltage V b is then applied to the substrate, resulting in a removal of oxides from the substrate and effective sputter cleaning.
[0016] It has been observed that two types of oxide may occur in plasma processing of materials. One is the “native oxide” that forms naturally on many materials when they are exposed to ambient environments. The other is a re-oxidation that forms on the substrate surface during plasma processing due to the outgassing of water moisture adsorbed on the substrate and the vacuum chamber. Without additional care being taken, the thickness of the oxide due to re-oxidation could exceed the native oxide removed in the previous step.
[0017] Depending on the vacuum system and the substrate utilized, outgassing may take 30 minutes to several hours. In ideal conditions, during this time period, no film depositation should occur. In order to remove the native oxide and prevent the surface from re-oxidation, the sputtering rate should be maintained at greater than the sticking rate of water molecules. The sputter-cleaning rate depends on both the ion current density and the ion energy at the substrate.
[0018] In the present invention, the high ion current density comes from the discharge power of the filament current and the discharge voltage V d and is enhanced by the magnetic field. The current density is much higher than that produced by the magnetron alone. After the outgassing process has diminished, and the surface oxide has been removed, and with the ion bombardment continuing, the magnetron power supply V T is turned on. Now sputtering of the target material starts, as does the deposition of the film. During the transition from the sputter cleaning to the film deposition, the substrate bias V b remains high (˜100-1000V) for set time, and then reduces to a low level (˜50V) to ensure a good interface. Since in this technique the current density and the ion energy can be controlled separately, the broad range of requirements for the cleaning and film deposition can be met readily.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The invention will now be described by way of exemplary embodiments with reference to the accompanying simplified, diagrammatic, not-to-scale drawings. In the drawings:
[0020] [0020]FIG. 1 is a cross-sectional view of an embodiment of the apparatus of the present invention;
[0021] [0021]FIG. 2 is a cross-sectional view of an embodiment of the present invention during sputter-cleaning of a workpiece; and
[0022] [0022]FIG. 3 is a cross-sectional view of an embodiment of the present invention during the sputter-coating of a workpiece.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The present invention is a plasma enhanced coaxial magnetron sputter-coating system for coating the internal surface of a cylindrical workpiece. The following description is presented to enable one of ordinary skill in the art to make and use the invention and to incorporate it in the context of particular applications. Various modifications, as well as a variety of uses in different applications will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to a wide range of embodiments. Thus, the present invention is not intended to be limited to the embodiment presented, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
[0024] Introduction
[0025] The present invention provides a method and apparatus for sputter-cleaning the surface of a target object (workpiece) and for sputter coating (film deposition) thereon subsequent to the cleaning. Additionally, in the apparatus of the present invention, a mesh anode configured to reside substantially parallel to the surface of the target object is provided in order to ensure a uniform plasma distribution parallel to the surface of the target object and to ensure uniform sputter-cleaning and film deposition thereon. The mesh anode facilitates uniform sputter coatings of the interior surfaces of generally cylindrical objects having high aspect ratios.
[0026] The present invention operates in several steps. First the volume surrounding the magnetron and the surface to be coated is evacuated with a vacuum pump, removing the gas from the chamber. Then, a working gas such as argon is introduced into the chamber, and continually flows through the chamber throughout the cleaning and deposition processes. Next, plasma is generated, and ions from the plasma are bombarded with the surface of the target object to provide sputter cleaning. As the surface is cleaned, outgassing of water molecules from the surface of the target object and from the surface of the vacuum chamber occurs. The sputter cleaning must be maintained during the offgassing to prevent surface re-oxidation. After the sputter cleaning is complete and the offgassing has finished, the sputter coating occurs and results in a uniform film deposition onto the surface of the target object.
[0027] Details of the Present Invention
[0028] A cross-sectional view of the apparatus of the present invention is shown in FIG. 1. The apparatus generally comprises a magnetron assembly 100 centered within in a workpiece 102 (typically a conductive, substantially cylindrical object), with the magnetron assembly 100 and the workpiece 102 being housed in a vacuum chamber 104 . Alternatively, the ends of the workpiece 102 may be sealed and the interior volume of the workpiece 102 may be evacuated to form a vacuum.
[0029] The magnetron assembly 100 , in turn, comprises a cooling system 106 , a plurality of ring magnets 108 surrounding and cooled by the cooling system 106 , a cylindrical sputtering material 110 , though not, strictly speaking, a part of the magnetron assembly 100 , electron emitters 112 (e.g. tungsten filaments or filaments of a like material), a cylindrical meshed anode 114 (composed of a wire screen), a electron discharge voltage supply V AE 116 for applying a potential between the anode 114 and the electron emitters 112 , a alternating voltage supply V AC 118 for heating the electron emitters 112 to a thermionic temperature in order to generate free electrons, a workpiece biasing voltage supply V WV 120 for negatively biasing the workpiece 102 with respect to the anode 114 (and also connected with the vacuum chamber 104 ), and a magnetron voltage supply V M 122 for biasing the cylindrical sputtering material 110 with respect to the electron emitters 112 . Note that some of the references for the structures described in this paragraph may be found on FIGS. 2 and 3. This is simply for the convenience of minimizing the cluttering of the figures.
[0030] In practice, the present invention operates to provide sputter cleaning and then smoothly transitions to provide sputter deposition of the sputtering material 110 onto the surface of the workpiece 102 . These two operations are detailed as follows.
[0031] Sputter Cleaning Operation
[0032] The sputter cleaning operation of the present invention is shown in the cross-sectional view presented in FIG. 2. Before sputter cleaning begins, a vacuum pump (not shown) removes gasses from the vacuum chamber 104 via an outlet, creating a vacuum (typically in the low 10 −6 Torr range). A working gas, preferably argon, is then introduced (typically increasing the pressure to a few few milli-Torr) via a working gas inlet. The working gas is continually circulated through the vacuum chamber 104 throughout both the sputter cleaning and the sputter deposition processes.
[0033] After the evacuation of gasses from the vacuum chamber 104 and the subsequent circulation of the working gas has begun, the alternating voltage supply V AC 118 is applied to the electron emitters 112 , heating the material of the electron emitters 112 to a thermionic temperature (e.g., ˜2000° C. for tungsten), and generating free electrons. An electron discharge voltage supply V AE 116 provides a potential (typically about 50 V) between the anode 114 and the electron emitters 112 , resulting in electron migration from the emitter 112 toward the anode 114 . Due to the strong magnetic field generated by the plurality of ring magnets 108 , the electrons will experience many collisions with the working gas en-route to the anode 114 , resulting in high ionization of the working gas, thereby producing a plasma 200 in the region between the cylindrical sputtering material 110 and the anode 114 .
[0034] It is important to note that the flux lines 202 surrounding each one of the plurality of ring magnets 108 are circular and, therefore, irregular with respect to the surface of the cylindrical sputtering material 110 . The anode 114 of the present invention is designed to overcome this limitation by partially trapping the plasma 200 between the cylindrical sputtering material 110 and the anode 114 , resulting in better circulation, and thus improved uniformity of the plasma distribution along the surface of the workpiece 102 . Without the wire mesh anode 114 , the plasma 200 distribution would be somewhat irregular, resulting in the deposition of a non-uniform coating during the sputter coating process and irregular cleaning during the cleaning process.
[0035] A negative workpiece biasing voltage supply V WV 120 is then applied to the workpiece 102 with respect to the anode 114 and the vacuum chamber 104 . Ions 204 are then drawn out of the plasma 200 from the anode 114 to the surface of the workpiece 102 . The bombardment of ions 204 onto the surface of the workpiece 102 results in sputter cleaning and a removal of oxides. Once the surface is sufficiently clean, the magnetron voltage supply V M 122 is powered and the cylindrical sputtering material 110 is sputtered onto the surface of the workpiece 102 , beginning the sputter deposition operation.
[0036] It is important to properly transition from sputter cleaning to sputter deposition to ensure that the surface of the workpiece 102 remains clean. Two types of surface oxides may occur in plasma processing of materials. The first is a native oxide that forms naturally on many materials when they are exposed to ambient environments. The other oxide that may form on the surface is a reoxidation during plasma processing due to the outgassing of water adsorbed on the workpiece 102 and the vacuum chamber 104 . If extra care is not taken, the thickness of the oxide due to re-oxidation could be much thicker than the native oxide and the coating would perform poorly. Both the removed native oxide and the water outgassed from the workpiece 102 and the vacuum chamber 104 should be removed prior to the sputter deposition operation begins. Depending on the rate of flow of the working gas through the vacuum chamber 104 (a function of the vacuum system) and the particular workpiece 102 , removal of these products generally takes in the neighborhood of 30 minutes to a few hours. Ideally, during this time, no sputter deposition occurs. In order to remove the native oxide and prevent the surface of the workpiece 102 from re-oxidation, the sputtering cleaning rate should be maintained at greater than the sticking rate of water molecules.
[0037] The sputter cleaning rate depends on both the ion current density and the ion energy at the surface of the workpiece 102 . In the present invention, a high ion current density is provided by a combination of the discharge voltage, the anode/emitter electron discharge voltage supply V AE 116 and the power supply V AC 118 to the electron emitters 112 , and is enhanced by the magnetic field provided by the plurality of ring magnets 108 . This resulting current density is much higher than that produced as a result of the magnetron voltage supply V M 122 alone. After the outgassing process has diminished and the surface oxide has been removed, and with ion bombardment from the sputter cleaning operation continuing, the magnetron voltage supply V M 122 is turned on.
[0038] Sputter Deposition Operation
[0039] A cross-sectional view of the apparatus of the present invention during the sputter deposition operation is provided in FIG. 3. After the removal of oxides has been completed and the magnetron voltage supply V M 122 has been turned on, the sputter deposition process begins. During the transition from the sputter cleaning process to the film deposition process, the negative bias of the workpiece 102 with respect to the anode 114 caused by the workpiece biasing voltage V WV 120 remains high (generally approximately 100 to 1000 V), for a time and is then reduced to a low level (generally approximately 50V) to ensure a good interface. Since the current density and the ion energy can be controlled through separate power sources, a broad range of requirements for sputter cleaning and sputter deposition processes can readily be met.
[0040] The apparatus of the present invention is readily applicable for the deposition of many metallic coatings (non-limiting examples of which include Ti, Al, Fe, Ni, Cr, and W), as well as various nitrides, oxides, or carbides (non-limiting examples of which include TiN, Al 2 O 3 , and WC) onto the surface of a workpiece 102 . An important aspect of the present invention lies in the fact that it provides high but independent control of ion-to-neutral flux for the sputter deposition process. A high ion-to-neutral ratio in the plasma is desired for high quality coatings. Since the ion current is mainly controlled by the power to the electron emitters 112 , which comprises the power supply V AC 118 and the electron discharge electron discharge voltage supply V AE 116 , and the flux of neutrals in the plasma is controlled by the magnetron voltage supply 122 , a high electron discharge power with a low magnetron power may be used to obtain the high ion-to-neutral ratio. In other cases, where a low ion-to-neutral ratio may be needed, both power supplies may be easily adjusted since they are nearly independent. It is also noteworthy that a much higher sputtering rate of the target material can be achieved through the use of filaments for the electron emitters 112 because of the extra electrons, allowing for an increased rate of sputter coating.
[0041] In addition to these advantages, the meshed anode 114 uniformly surrounds the magnetron, providing a uniform field for the magnetron. Therefore, a uniform plasma can be generated, providing a uniform sputtering of the surface of the workpiece 102 , and hence a uniform coating can be obtained. Additionally, since the anode 114 is also electrically connected with the vacuum chamber 104 , it provides the workpiece 102 with a uniform electric field through the application of the potential difference created by the workpiece biasing voltage supply 120 . Thus, the voltage V AE applied between the meshed anode 114 and the electron emitters 112 not only enhances the production of the plasma; it also provides the magnetron 100 with a uniform electric field with respect to the surface of the workpiece 102 , ensuring a constant plasma density along the surface of the workpiece 102 which allows for a uniform erosion of the target material and uniform sputtering deposition on the tube. An advantage of this configuration is that it allows the magnetron system 100 to be extended for longer workpieces 102 (i.e., workpieces 102 having a high aspect ratio) without sacrificing the uniformity of the sputter coating and sputter deposition operations. | A plasma-enhanced coaxial magnetron sputter-cleaning and coating assembly for sputter-cleaning and coating the interior surfaces of a cylindrical workpiece is provided. The apparatus sputter-coats the workpiece using a cylindrical sputtering material, the material having an interior and an exterior. The apparatus includes a core cooling system surrounded by a ring magnet assembly including a plurality of axially aligned ring magnets, with the core cooling system and the ring magnet assembly axially aligned with, and residing in the interior of, the cylindrical sputtering material. A cylindrical-shaped filament circumferentially surrounds the exterior of the cylindrical sputtering material. An anode comprised of a wire screen circumferentially surrounds, and is external to the filament; whereby the apparatus for plasma-enhanced coaxial magnetron sputter-cleaning and coating may be housed inside the workpiece in order to sputter-clean and coat the interior of the workpiece. | 2 |
BACKGROUND OF THE INVENTION
The present invention is in the field of floating disc brakes having a caliper guided by pins extending parallel to the axis of said disc.
As is well known, during operation of a floating disc brake, the caliper is guided by pins thereon, which slide in holes within a fixed member spanning the disc. In order to eliminate the intrusion of dust or other particles in the holes, they are closed at one end, i.e. they are blind holes. One disadvantage of such apparatus resides in its inability to easily exhaust air therefrom as a close fitting pin slides toward the blind end of the hole.
SUMMARY OF THE INVENTION
In accordance with the present invention the above disadvantage is eliminated by providing a floating disc brake having a caliper guided by pins, wherein the pins are covered by bags of resilient material, such as rubber, and the bags contain a groove through their length for passing air between the blind hole and the area outside said blind hole.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1, 2 and 3 are, respectively, a plan view, a front view, and a side elevational view, of a floating disc brake having guide pins on the caliper.
FIG. 4 is a cross sectional view, taken along line IV--IV of FIG. 1, of the arrangement of a guide pin in a blind hole.
FIG. 5 is a cross sectional view illustrating the resilient bag surrounding the guide pin.
FIG. 6 is a side view of a pin illustrating a resilient bag having helical grooves on the outside thereof.
FIG. 7 is a cross-sectional view of FIG. 6.
DETAILED DESCRIPTION
In the example shown in the drawings, particularly in FIGS. 1, 2 and 3, a fixed member (9), spanning a disc (1), essentially comprises two arms (9) and (9') forming a U-shape as viewed in FIG. 2 in the axial direction of the disc. The fixed member (9) is fixedly secured to, for instance, the knuckle of an automobile by screws (not shown) passing through screw holes (12). The two arms (9) and (9') of the fixed member are respectively extended over the periphery of the disc (1) in the axial direction of the disc. Also, as is apparent from FIG. 3, the tips of fixed member (9) are further extended downwardly in a bent manner.
In FIG. 4, there is indicated in a section on a much enlarged scale a part of the fixed member (9) which extends over the periphery of the disc. As is apparent in this figure, a blind hole (10) is provided in the fixed member (9), and pin (6) is inserted in the blind hole (10) with a bag (8) covering the pin. The relationship between pin (7), on the other side of the apparatus as viewed in FIG. 1, and a blind hole in arm (9'); is the same as that described for pin (6) and arm (9). An air passage hole (13) is provided through the bottom wall of the bag (8). Furthermore, four longitudinal grooves (11), shown in FIG. 5, are provided in the internal surface of the bag (8) to extend the entire length of the bag. The air passage and grooves permit the air compressed at the bottom of the blind hole (10) to be exhausted to the outer atmosphere when the pin is inserted therein. Conversely, the grooves (11) may be provided on the outer surface of the bag (8), and such a procedure will render the bag easier to manufacture. Alternatively, the grooves (11) may also be provided to extend helically over the entire surface of the bag thereby to provide a retracting force for the pin due to the resilience of the helical threads thus provided. Both latter features are illustrated in FIGS. 6 and 7. As shown there the bag (8a) has helical grooves (11a) which are on the outside of the bag. The pins (6) and (7) are fixed to a caliper (5) by means of screws, one of which is shown in FIG. 4.
In the above described example, a pressing device (3), comprising a piston and a cylinder, is provided inside one side part of a caliper (5). On the disc-side of the piston there is provided an inner pad (2) which is moved to the right, as shown in FIG. 3, when the brake actuates the piston. On the other side part of the caliper (5), an outer pad (4) is secured. When the pressing device (3) operates to depress the inner pad (2) toward the disc (1), the reactive force causes the entire caliper (5) to move toward the left as viewed in FIG. 3, whereby the outer pad (4) is also pressed toward the disc. The above described movement of the caliper retracts the pins (6) and (7) from the respective blind holes in the fixed member.
To meet the requirements of this operation, a high precision of fabrication is demanded with respect to the space between the two blind holes (10) and the pins (6), (7) respectively, as well as regarding their cross sectional area and parallelism. However, it is preferable that one of the pins is not covered with a bag but is placed directly in the blind hole to slide therein while a clearance is provided in the space between the other pin and the blind hole where the bag (8) is interposed. | A floating disc brake is diclosed having a caliper which is guided by pins therein which slide axially within blind holes provided in a fixed member. At least one of the pins is enclosed in a resilient bag having air passages therein for permitting the compressed air in the blind hole to escape. | 5 |
BACKGROUND OF THE INVENTION
The invention is directed to a printed circuit board for electronics, and particularly a printed circuit board formed of a flexible carrier material.
It is known to solder components onto a surface that carries the interconnects directly to the interconnects from above. This is referred to as the SMD technique (Surface Mounted Devices).
SUMMARY OF THE INVENTION
An object of the invention is to specify an easily automatable and heat-stable semiconductor contact both for linear as well as for planar semiconductor arrangements.
This is inventively achieved in an arrangement of the type initially cited wherein the interconnects are composed of a solderable metal or of a solderable alloy at least at the surface at which they can be connected to the components. The components, and particularly semiconductor chips, are then connected to the conductors by melting the solderable material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of a contacted light-emitting diode in film technique;
FIG. 2 shows a row of 10 diodes in a pattern having a grid dimension of 0.5 mm;
FIG. 3 shows an example of an offset arrangement of 20 light emitting diodes in a row;
FIG. 4 shows a cross-section through a pluggable arrangement of the invention;
FIG. 5 shows an alphanumerical display in stacked technology;
FIG. 6 shows a cross-section through an element of a two-plane contacting; and
FIG. 7 shows a plan view of two elements in a 2-plane contacting.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A thin (approximately 1 μm) copper layer 2 is applied (coated in currentless fashion or vapor-deposited) onto a flexible plastic carrier film 1 (for example polyethylene terephthalate, polymide, epoxy resin/fiberglass fabric). This copper layer 2 is subsequently galvanically reinforced to about 5 μm. This reinforcement is necessary so that the interconnect structure can be etched and, moreover, it increases the heat elimination out of the contact zone. After the etching of the desired interconnects, an approximately 5 to 20 μm thick tin layer 3 or some other solderable metal or a solderable alloy is likewise electro-deposited. The contacting of the component 4, which is a semiconductor chip and particularly a LED (light emitting diode) here, is performed with a solder-die after the crystal has been positioned at a metal-free region. One respective metal contact 6 for the semiconductor is arranged on interconnect 3. The insertion depth, the temperature of the crystal, and the pressure on the crystal can be set in a defined fashion with this solder die. The temperature must be selected such that the metal of the interconnect melts and the chip sinks into the carrier film for mechanical anchoring as shown at 100 in FIG. 1. The pn-junction of the semiconductor is referenced 5.
The geometry of the interconnects, and particularly their spacing is dependent on the dimensions of the semiconductors to be contacted, and is dependent on the desired current-loadability of the component 4.
However, it is also possible to etch and tin plate the interconnects on a Cu film laminated with a plastic film in order to contact the semiconductor chips. A further increase in the heat elimination can thus be achieved. However, the tolerances, and particularly the spacing of the interconnects and the thickness of the chips, must be extremely precisely observed.
The desired interconnect geometry for the contacting can also be etched in a solderable metal film (for example, tin film) that is laminated on a carrier film. No further work cycles are then required.
Constructing the interconnects of easily meltable layers is especially advantageous because additional techniques to prevent short-circuiting of the pn-junction of the semiconductor are not required. The melting ofthe metals (Sn or SnPb alloy) and of the plastic in the environment of the crystal also removes a Cu layer from the jeopardized zone in that these substances yield to the pressure of the crystal. A significant advantage in this type of contacting is that, in contrast to the nail-head bonding, only one work step is required in order to contact the p-side and the n-side. Moreover, this method offers the possibility of simultaneously contacting a plurality of crystals, or of contacting a semiconductor circuit comprising a plurality of terminals, in one work cycle.
It has proven especially advantageous for the alloy formation in the contact zone to use a semiconductor crystal that carries an additional gold layer 6 over the alloyed-in ohmic contacts.
The recited contacting is very suitable for a line arrangement, particularly given a slight spacing between the individual components, since a significantly tighter packing of the semiconductors is possible than in a traditional technique. As an example, a row of 10 diodes with a grid dimension pattern of 0.5 mm is shown in FIG. 2. An arrangement comprising 20 offset diodes with a grid dimension of 211 μm is recited in FIG. 3. In case a pluggable component--both a discrete element as well as an arbitrary multiple row--is to be manufactured, it is possible to bring the plastic carrier into a shape on the basis of suitable methods (for example deep drawing or hot-pressing) to punch feet and to then solder the semiconductor in, as shown in FIG. 4. For better solderability of the feet 8, a film laminated with copper on both sides can be employed at these locations (FIG. 4). The arrangement shown in this FIG. 4 has an M shape such that the semiconductor component 4 is centrally soldered to the outer interconnects and is embedded in a casting compound 7. The inside interconnects are only provided for facilitating the solderability to the printed circuit board.
This technique offers particular advantages, and specifically for a light-emitting diode arrangement in a matrix form. This method, referred to as the stacked technique, for example results in an alpha-numeric display having 5×7 light-emitting diodes in a grid dimension of 1 mm, as shown in FIG. 5. Five carrier films each having 7 light-emitting diodes are thus arranged on top of one another and are secured such that a grid dimension of 1 mm also arises between the lines.
FIG. 6 shows a further possibility for manufacturing a matrix, whereby the leads to the light-emitting diodes are arranged on two sides of a thin plastic film 9. It is thus possible to solder a planar interconnect 11 to the gold layers 6 of the semiconductor at the inside in the contact zone, and to solder a lower interconnect 12 at the other side. For reinforcing, the carrier film comprising the two interconnect levels is glued onto a thick, insulating support 10. This technique, shown in FIG. 6 as a 2-plane contacting represents an interlayer connection. Here, too, the two metal coatings 6 of the semiconductor 4 are connected in one work cycle to the two leads 11, 12 on the two sides of the thermoplastic carrier film 9.
Although various minor changes and modifications might be proposed by those skilled in the art, it will be understood that I wish to include within the claims of the patent warranted hereon all such changes and modifications as reasonably come within my contribution to the art. | An easily automated and heat-stable semiconductor contacting system for linear and planar SMD components, particularly LED arrangements. SMD components are applied to a carrier film coated with interconnects. The interconnects are entirely or partly formed of solderable material for simpler contacting through melting. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. application Ser. No. 11/284,242 filed on Nov. 21, 2005, which claims priority to U.S. Provisional Patent Application No. 60/667,523 filed Apr. 1, 2005, which is incorporated by reference as if fully set forth.
FIELD OF INVENTION
The present invention relates to a wireless communication system including a plurality of multi-band access points (APs) and a multi-band wireless transmit/receive unit (WTRU), (i.e., a mobile station). More particularly, the present invention is related to a method and apparatus for selecting a particular one of the multi-band APs to associate with based on frequency band information transmitted from the multi-band APs to the multi-band WTRU.
BACKGROUND
A typical wireless local area network (WLAN) includes an AP which provides radio access to WTRUs in a coverage area of the AP. The AP is comprised by a basic service set (BSS) which is a basic building block of an IEEE 802.11-based WLAN. Multiple BSSs may be interconnected through a distribution system (DS) to form an extended service set (ESS).
The WLAN may be configured in an infrastructure mode or an Ad-hoc mode. In the infrastructure mode, wireless communications are controlled by an AP. The AP periodically broadcasts beacon frames to enable WTRUs to identify, and communicate with, the AP. In the Ad-hoc mode, a plurality of WTRUs operate in a peer-to-peer communication mode. The WTRUs establish communication among themselves without the need of coordinating with a network element. However, an AP may be configured to act as a bridge or router to another network, such as the Internet.
The WTRUs and the AP may be configured to utilize multiple frequency bands for communication. In a conventional wireless communication system, a multi-band WTRU transmits multiple probe requests on different channels of a frequency band to discover if there are any APs available in the area. Once an AP receives the probe request, it sends a probe response packet to the WTRU. The AP will send the probe response packet on its operating channel in a particular frequency band. The probe response packet contains required parameters, such as supported rate, or the like, for the WTRU to associate with the AP. The WTRU will send an association request packet and waits for an association response packet from an AP for further data communication.
Once associated, the multi-band WTRU may scan other frequency bands in search of a better communication band by transmitting a probe request packet and waiting for a probe response packet. Upon receiving another probe response packet, the WTRU compares the frequency bands and/or the AP and selects a more preferable frequency band and/or AP.
In the conventional wireless communication system, the multi-band WTRU must scan and compare different frequency bands to determine the frequency band that provides the best quality of wireless communications. However, these scanning and comparison functions are time-consuming and require a significant amount of battery power. A method and apparatus for reducing the amount of time and battery power required to make frequency band and channel selection decisions is desired.
SUMMARY
The present invention is related to a method and apparatus for selecting one of a plurality of multi-band APs to associate with a multi-band WTRU. The multi-band APs broadcast frequency band information regarding multiple frequency bands on which the multi-band AP is configured to operate. The multi-band WTRU selects a particular multi-band AP to associate with and a frequency band to use to communicate with the selected multi-band AP based on the frequency band information. If the multi-band WTRU receives frequency band information from the selected multi-band AP which indicates that a characteristic, (e.g., throughput, path loss, load, capacity, backhaul), of the selected frequency band is unacceptable, the multi-band WTRU determines whether to disassociate with the selected multi-band AP or to continue to associate with the selected multi-band AP via a different frequency band.
BRIEF DESCRIPTION OF THE DRAWINGS
A more detailed understanding of the invention may be had from the following description, given by way of example and to be understood in conjunction with the accompanying drawings wherein:
FIG. 1 shows a wireless communication system including a plurality of multi-band APs and a multi-band WTRU which operate in accordance with the present invention;
FIG. 2 is an exemplary beacon frame which comprises frequency band information transmitted from the multi-band APs to the multi-band WTRU of the wireless communication system of FIG. 1 ;
FIG. 3 is a flow diagram of a process for the multi-band WTRU to select one of the multi-band APs to associate with in accordance with the present invention;
FIG. 4 is a flow diagram of a process for the multi-band WTRU to determine whether to change a particular frequency band used for wireless communications with a multi-band AP or to associate with a different multi-band AP in accordance with the present invention; and
FIG. 5 is a flow diagram of a process for establishing a wireless communication link between the multi-band WTRU and a preferable multi-band AP over a preferable frequency band in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereafter, the terminology “WTRU” includes but is not limited to a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, or any other type of device capable of operating in a wireless environment. Such WTRUs include, but are not limited to, phones, video phones, and Internet ready phones, personal data assistances (PDAs) and notebook computers with wireless modems that have network capabilities.
When referred to hereafter, the terminology “AP” includes but is not limited to a Node-B, a base station, a site controller or any other type of interfacing device in a wireless environment that provides other WTRUs with wireless access to a network with which the AP is associated.
The features and elements of the present invention may be implemented on a single IC, (such as an application specific integrated circuit (ASIC)), multiple ICs, discrete components or a combination of discrete components and ICs.
The present invention is applicable to any type of wireless communication systems including, but not limited to, 802.x-based wireless communication systems.
FIG. 1 shows a wireless communication system 100 including a plurality of multi-band APs 105 1 - 105 N and a multi-band WTRU 110 which operate in accordance with the present invention. Each of the multi-band APs 105 1 - 105 N and the multi-band WTRU 110 operate on at least two frequency bands. The multi-band APs 105 1 - 105 N transmit frequency band information 115 1 - 115 N which indicates the different multi-bands that the respective APs 105 1 - 105 N are configured to operate on. Each of the multi-band APs 105 1 - 105 N include a respective transceiver 120 1 - 120 N and a respective processor 125 1 - 125 N . Each respective transceiver 120 1 - 120 N is configured to operate on at least two different frequency bands. Each respective processor 125 1 - 125 N generates and formats the respective frequency band information 115 1 - 115 N and provides it to the transceiver 120 1 - 120 N for transmission. The multi-band WTRU 110 also includes a transceiver 130 and a processor 135 . The transceiver 130 is configured to operate on at least two different frequency bands. The processor 135 processes the frequency band information 115 1 - 115 N received by the transceiver 130 from the multi-band APs 105 1 - 105 N , selects a multi-band AP 105 to associate with, and a frequency band to use in communication with the selected multi-band AP 105 , based on the frequency band information 115 1 - 115 N .
The multi-band WTRU 110 and the multi-band APs 105 1 - 105 N may use any management, control or data packet to provide the frequency band information to the multi-band WTRU 110 . For example, an authentication frame, (which is a management frame), can also be used to send multi-band frequency information. Similarly, this packet can be piggybacked on any of the current or future WLAN packets.
Alternatively, a proprietary message exchange between the multi-band WTRU 110 and the multi-band APs 105 1 - 105 N may also be utilized to provide the frequency band information to the multi-band WTRU 110 .
FIG. 2 shows an exemplary beacon frame which comprises frequency band information 115 transmitted from each of the multi-band APs 105 1 - 105 N to the multi-band WTRU 110 of the wireless communication system 100 of FIG. 1 . The frequency band information 115 indicates whether a particular multi-band AP 105 supports multiple frequency bands 205 1 - 205 N , channel numbers 215 and timing information 220 or the like.
The frequency band information 115 may further include quality metric information 210 1 - 210 N for each of the frequency bands 205 1 - 205 N . The quality metric information may include, but is not limited to, path loss, load, (e.g., the number of associated WTRUs 110 ), throughput, capacity and backhaul on each frequency band.
FIG. 3 is a flow diagram of a process 300 for establishing a wireless communication link between a particular one of 115 1 - 115 N and the multi-band WTRU 110 in the wireless communication system 100 of FIG. 1 based on frequency band information 115 1 - 115 N transmitted from the multi-band APs 105 1 - 105 N to the multi-band WTRU 110 . In step 305 , a plurality of multi-band APs 105 1 - 105 N broadcast frequency band information 115 1 - 115 N regarding multiple frequency bands on which the respective multi-band APs 105 1 - 105 N are configured to operate. The frequency band information 115 1 - 115 N may be broadcast in a beacon frame, as shown in FIG. 2 . In step 310 , a multi-band WTRU 110 receives and processes the frequency band information 115 1 - 115 N . In step 315 , the multi-band WTRU 110 selects a particular one of the multi-band APs 105 1 - 105 N to associate with, and a frequency band to use to communicate with the selected multi-band AP 105 based on the frequency band information 115 1 - 115 N .
FIG. 4 is a flow diagram of a process 400 for the multi-band WTRU 110 to determine whether to change a particular frequency band used for wireless communications with a multi-band AP 105 , or to associate with a different multi-band AP 105 in accordance with the present invention. In step 405 , the multi-band WTRU 110 associates with a particular multi-band AP 105 on a particular frequency band. In step 410 , the multi-band WTRU 110 receives frequency band information 115 from the particular multi-band AP 105 including a quality metric which indicates that the particular frequency band has, for example, poor throughput. In step 415 , the multi-band WTRU 110 either disassociates with that the multi-band AP 105 and associates with another multi-band AP 105 continues to associate with the same multi-band AP 105 over a different frequency band for which the frequency band information 115 includes a quality metric which indicates a good, (i.e., high), throughput.
FIG. 5 is a flow diagram of a process 500 for establishing a wireless communication link between the multi-band WTRU and a preferable multi-band AP over a preferable frequency band in accordance with the present invention. In step 505 , a multi-band WTRU 110 broadcasts an association request packet or a probe request packet which is received by a plurality of multi-band APs 105 1 - 105 N . The multi-band WTRU 110 may include an indication of the multi-band capability and related information of the WTRU 110 in the request packet. In step 510 , each of the multi-band APs 105 1 - 105 N sends an association response packet or a probe response packet to the multi-band WTRU 110 which includes frequency band information 115 1 - 115 N in accordance with the multi-band capability of the WTRU 110 . In step 515 , the multi-band WTRU 110 selects a preferable frequency band and a preferable multi-band AP 105 to associate with based on the frequency band information 115 1 - 115 N .
In another embodiment, the wireless communication system 100 may also include a single-band AP and a single-band WTRU, in addition to the multi-band APs 105 1 - 105 N and the multi-band WTRU 104 a . If a single-band WTRU is associated with a multi-band AP 105 , the information regarding the multiple frequency bands of the multi-band AP 105 other than information regarding the frequency band on which the single-band WTRU is configured to operate will be simply ignored by the single-band WTRU since the single-band WTRU not configured to communicate on multiple frequency bands. The single-band AP broadcasts its information regarding its single frequency band, (such as timing, load, or the like) in a beacon frame. Both a single-band WTRU and a multi-band WTRU 110 may utilize this information to decide whether or not to associate with the single-band AP.
In accordance with the present invention, the multi-band WTRU 110 is not required to consume significant time and battery power for scanning various frequency bands in search of an adequate AP to associate with. Moreover, by providing the multi-band WTRU 110 with quality metrics of each frequency band, (such as throughput), the WTRU is enabled to optimize not only its own throughput, but also the throughput of the AP 105 .
Although the features and elements of the present invention are described in the preferred embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the preferred embodiments or in various combinations with or without other features and elements of the present invention. | A method and apparatus for selecting one of a plurality of multi-band access points (APs) to associate with a multi-band wireless transmit/receive unit (WTRU) are disclosed. The multi-band APs broadcast frequency band information regarding multiple frequency bands on which the multi-band AP is configured to operate. The multi-band WTRU selects a particular multi-band AP to associate with and a frequency band to use to communicate with the selected multi-band AP based on the frequency band information. If the multi-band WTRU receives frequency band information from the selected multi-band AP which indicates that a characteristic, (e.g., throughput, path loss, load, capacity, backhaul), of the selected frequency band is unacceptable, the multi-band WTRU determines whether to disassociate with the selected multi-band AP or to continue to associate with the selected multi-band AP via a different frequency band. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to an electroluminescent device comprising a first electrode, a second electrode and an ionic, organic layer which is in contact with said first electrode, which layer contains a conjugated compound and mobile ions. The invention also relates to a method of manufacturing an electroluminescent device comprising an ionic layer, which layer contains mobile ions.
An electroluminescent (EL) device is a device built up of an electroluminescent layer, which layer emits light when a voltage is applied across electrodes which are in contact with said layer. Such a device can be used, inter alia, as a light source whose light output can be varied in a simple manner by varying the applied voltage. An assembly of independently addressable EL devices, for example in the form of a matrix of light-emitting areas, can be used as a display.
Apart from EL devices based on inorganic materials, such as GaAs, also EL devices based on organic materials are known. Organic EL (oEL) devices on the basis of low-molecular weight materials and on the basis of polymers are known. Known oEL devices are single-layer devices, which means that, apart from the electrodes, the device only comprises the electroluminescent layer, or they are multilayer devices.
The performance of an organic EL device, measured, for example, in terms of the luminance at a specific voltage, depends to a substantial degree on which electrode materials are used. In general, it is assumed that in the case of electrons, the number of electrons injected depends exponentially on the difference between the work function of the electrode and the electron affinity of the organic layer. In the case of holes, the difference between the work function of the electrode and the ionization potential of the organic layer is of corresponding importance. This dependence applies mutatis mutandis also to the EL efficiency, which is defined as the ratio between the number of photons emitted and the number of charge carriers injected, as said EL efficiency is governed by the ratio between the electron current and the hole current. Consequently, it has been found in practice that in the case of, in particular, single-layer devices, the performance necessary for the above-mentioned applications generally can only be achieved if the negative electrode, also referred to as cathode, comprises a metal having a low work function. A low work function is to be understood to mean herein a work function of approximately 3.0 eV or less. A known electrode material, i.e. calcium, meets this criterion. A disadvantage of such metals is that they degrade under the influence of air. Consequently, the service life of EL devices based on such metals is very limited under atmospheric conditions. A known measure to enable metals having a higher work function to be used as the cathode material consists in incorporating additional layers into the device. In general, the manufacture of such multilayer devices is laborious and expensive. Besides, the performance of the device still depends, in principle, on which electrode material is selected: the work function still has to be attuned to the ionization potential and electron affinity of the layers used. The layers and electrodes can only be optimized in conjunction with each other, not separately. Given the multitude of factors which determine the functionality of a layer, such as the layer thickness, the electrical conductivity, the ionization potential, the electron affinity, the band gap and the photophysics, the optimization of a multilayer device is laborious. Consequently, there is a clear need for a simple, single-layer oEL device, which permits electrodes having a high work function to be used without the performance of the device being adversely affected.
Such a device was described recently by Pei et. al., in Science (1995) vol. 269, 1086. In this known device, referred to as “light-emitting electrochemical cell” (LEC) by Pei et. al., an electrolyte, for example lithiumtrifluoromethanesulphonate, is added to a layer of a known electroluminescent material, such as a poly(phenylenevinylene), which causes, according to said publication, a p-n junction to be formed in situ by means of electrochemical doping of the EL material. This measure results, inter alia, in that the device emits light already at a voltage which corresponds approximately to the band gap of the EL material and in that EL efficiencies comparable to known polymer-based EL devices (pEL) are achieved while using electrode materials having a high work function such as gold and aluminium.
However, the known LEC has disadvantages. Although the known LEC makes use of electrodes having a high work function, this has no effect on the service life. Said service life is comparable to that of corresponding devices in which a cathode having a low work function is used instead of an electrolyte. As explained hereinabove, the service life of the latter devices under ambient conditions is very limited and definitely insufficient for the intended applications. A further disadvantages is that by means of diffusion the electrolyte can move through every organic layer while preserving its charge neutrality. Consequently, a multilayer construction of the known LEC in which only one layer contains the electrolyte is not feasible. In addition, it is difficult to disperse the electrolyte on a molecular scale in the customary EL materials, which, in general, are non-ionic and predominantly apolar.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the invention, inter alia, to provide an oEL device which does not have the above-mentioned drawbacks. The invention specifically aims at an oEL device whose service life under ambient conditions is much better, even without particular protective measures, than that of comparable, known LEC devices, even when the air is saturated with water vapour. Said device should have a good EL efficiency and have a satisfactory light output already at a low voltage. In addition, the EL efficiency of the device should be substantially independent of the work function of the electrodes used, so that it is possible, inter alia, to use a material having a high work function as the cathode material or to use the same material for both the anode and the cathode. The expression “substantially independent” is to be understood to mean herein that the charge injection is no longer determined by the above-mentioned exponential dependence. A further object is to disperse the ions of the electrolyte on a molecular scale. It should be possible to choose the ionic characteristics of a layer substantially independently of the charge-transporting and electroluminescent characteristics of the layer. The expression “charge transport” is to be understood to mean only the transport of electrons and holes necessary for the electroluminescence, not the transport of ions. In the case of a multilayer structure, it should be possible, if necessary, to limit the presence of ions of a specific polarity to one or more layers. It should also be possible to manufacture the single-layer or multilayer EL device in a simple manner. In particular, it should be possible to achieve the intended properties with oEL devices which are exposed to ambient conditions during their manufacture.
These and other objects are achieved by means of an EL device of the type mentioned in the opening paragraph, which is characterized, in accordance with the invention, in that either only negatively charged ions or only positively charged ions are mobile relative to the first electrode. It has been found that the service life, under ambient conditions, of the EL device manufactured in accordance with the invention is much longer than that of comparable, known LEC devices in which both positive and negative mobile ions are used. Said service life is achieved without taking any protective measures. It has even been found that such devices can be operated for days in an atmosphere saturated with water vapour. It has also been found that a service life of several months in combination with good performances can be readily achieved. In a typical example, the EL efficiency was approximately 1.5% and the light output was approximately 500 Cd/m 2 at 5 V, while using a gold cathode and an indium tin oxide (ITO) anode.
For the cathode material use can suitably be made of materials having a high work function. In fact, the EL efficiency is substantially independent of the choice of the cathode material. Examples of suitable cathode materials are gold, platinum and other noble metals, aluminium, indium tin oxides.
For the electrode material use is advantageously made of metals which can be provided in liquid form, such as indium. They can be provided in a simple manner and an electrode thus formed proves to be non-porous. The absence of porosity has a favourable effect on the service life.
Said cathode materials can also suitably be used as anode materials. If the EL device has a “sandwich” structure, it is advantageous to use an electrode material which is transparent to the light to be emitted, such as an indium tin oxide (ITO). The presence of mobile ions compensated by immobile ions creates a “restoring force” if said mobile ions have been moved under the influence of an electric field or diffusion, which restoring force, in the case of multilayer devices as will be described hereinbelow, can be advantageously used. The inventive EL devices can be manufactured in a simple manner, while being exposed to air, by methods which are known per se.
In accordance with the invention, not only mobile ions but also immobile ions are present which serve to compensate the charge of the mobile ions. Charge neutrality is assumed, although it is not a prerequisite for all intended purposes. The mobility of ions depends, inter alia, on the temperature and the matrix in which they are present. For example, the mobility can be increased by gelation by adding a suitable solvent and/or heating. Other important factors are the size of the ion and the strength of the bond between oppositely charged ions. Preferably, a mobile ion is small and soft, and an immobile ion is large. The mobility of a mobile ion should be as high as possible. Dependent upon the applications, a suitable mobility of a mobile ion is 10 −14 cm 2 /Vs or more. The mobility of a suitable immobile ion is approximately 10 −19 cm 2 /Vs or less. Mobile as well as immobile ions should be chemically inert, particularly under the operating conditions of the device.
Suitable mobile anions are ions which are derived from, for example, Bronsted acids, such as halogenides, in particular I − , tosylates, triflates, carboxylates or Lewis-acid anions, such as BF 4 − . The mobile anions can be exchanged for others in a simple manner. Suitable mobile cations are, for example, alkaline (earth) metal ions, such as Na + or K + , or quaternary ammonium compounds, taking the above general guide lines into consideration. In the case of very small cations, such as Li + or maybe even H + , it is desirable to use an ion-conducting polymer, such as polyethylene oxide.
The ionic layer can only suitably be used in an EL device if a conjugated compound is present which transports the injected charges. If a single-layer device is used, the presence of a conjugated compound having an EL property in the ionic layer will additionally be necessary, which compound is often identical to the charge-transporting compound. By means of mixing or synthesis, the ionogenic compound can be combined with known charge-transporting and EL compounds, such as low-molecular weight fluorescent dyes, in particular coumarines, EL polymers, in particular polyphenylenevinylenes, or high-molecular or low-molecular weight derivatives of phenyl-biphenyl-1,3,4-oxadiazole or triphenylamine dimer or polyvinylcarbazole. It is required, however, that the ionogenic compound leaves the charge-transporting and/or electroluminescent properties of the layer obtained by using the conjugated compound substantially unchanged. This requirement will be met if the ionogenic compound has a much larger band gap and ionization potential and a much smaller electron affinity than the conjugated compound.
The ionic layer can be manufactured by means of methods which are known per se. Layer thicknesses vary typically from 25 to 500 nm, in particular from 50 to 150 nm.
The time-dependence of the current-voltage characteristic (CV) and of the luminance-voltage characteristic (LV) of the EL device in accordance with the invention was found to differ from that of the conventional devices in which no mobile ions are used. In operation, the CV characteristic of the latter devices is initially constant as a function of time, but deteriorates gradually, i.e. as a result of degradation, a constantly increasing voltage is necessary to maintain a constant current. However, the CV and LV characteristics of the device in accordance with the invention improve with time, i.e. the voltage required to obtain a specific current decreases continuously. In other words, at a constant voltage, the current and the luminance increase. Also the EL efficiency of the device improves, values of at least 1.0 to 1.5% being feasible. Only after a long period of time, typically several days to months the performance of the device decreases as a result of degradation. The time interval within which the improvement of the CV characteristic takes place can be shortened by a so-called activating operation. The term “activation” is to be understood to mean that a higher voltage is temporarily applied. This voltage typically is a factor of 2 to 4 higher than the voltage used during the life test. If the device is switched off for a short period of time, typically approximately ten seconds, almost immediately the same characteristic as after activating is obtained. If the device is switched off for a long period of time, for example approximately 10 minutes, the improvement stage has to be covered again. In accordance with the finding that the performance of the device is substantially independent of the electrode materials used, the performance obtained in “reverse bias” is comparable to that obtained in “forward bias”. The stability of the electrode material may differ as a function of the polarity of the applied voltage. It has been found that the activating time depends on the mobility of the ions. Shorter times suffice if the device is heated or if the ionic layer is gelated by means of a solvent. The activating time is also shorter as the layer is thinner.
It has been found that the service life of the device in accordance with the invention can be improved further by using an additional layer. Consequently, a preferred embodiment of the EL device in accordance with the invention is characterized in that said device comprises an additional layer, which layer is situated between the second electrode and the ionic layer and which contains a conjugated compound as well as such a quantity of mobile ions that the overall charge of these mobile ions is substantially compensated by immobile ions of the ionic layer. It is noted that the qualification “ionic layer” only makes sense in multilayer devices if immobile ions are used, which are substantially absent in the additional layer. Unlike known multilayer devices, the resultant freedom of construction does not have to be sacrificed to the attunement of the electron affinity and ionization potential of the relevant materials to the work function of the electrodes, as electrode-independence is guaranteed substantially by the presence of the ions. Both the additional layer and the ionic layer can be used as an EL and/or charge-transporting layer.
Suitable materials for the additional layer are the known EL and charge-transporting materials, such as a poly(phenylenevinylene). It is alternatively possible to use various additional layers, but this leads to a greater complexity. In a particular suitable configuration, the second electrode is used as the negative electrode, as in general the injection or charge transport of electrons needs to be improved. A particular, preferred embodiment of the EL device is characterized in accordance with the invention in that the ionic layer and the additional layer have substantially identical fluorescence spectra, ionization potentials and electron affinities. As the difference between the ionic layer and the additional layer consists merely in the presence and absence, respectively, of immobile ions, the conjugated parts can be selected so that the above characteristic is satisfied. This is in contrast to known multilayer devices in which a plurality of layers are used to create differences in ionization potential, electron affinity or fluorescence spectrum. The EL device in accordance with the invention combines the advantages of monolayer and multilayer devices. Such a device can be manufactured in a simple manner by successively providing the two layers or by using an inventive method which will be described in greater detail hereinbelow.
Another preferred embodiment of the EL device in accordance with the invention is characterized in that the immobile ion is formed by a charged substituent which is linked to the conjugated compound by means of a covalent, saturated bond. By combining the ionogenic and conjugated properties in one compound, the necessity of mixing various compounds can be dispensed with. A problem which often occurs during mixing is phase separation. This occurs, in particular, if ionogenic materials have to be mixed with non-ionogenic materials. As regards the intended device, however, it is advantageous to disperse the ions on a molecular scale. The ionogenic property can be introduced synthetically by using a charge group as the substituent of the conjugated compound. By linking the substituent by means of a covalent, saturated bond, the ionogenic property and the conjugated property can be introduced with a minimum of mutual interference. Therefore, suitable compounds can be obtained in a simple manner by combining suitable conjugated and ionogenic compounds.
A particular, preferred embodiment of the EL device in accordance with the invention is characterized in that the immobile ion of the ion layer is formed by a polymer. The use of polymeric materials has advantages. The high-molecular weight ensures that the ionic portions which form part of the polymer are indeed immobile. Further, polymers are, in general, readily processable, amorphous and suitable for producing flexible devices having large surface areas by using simple techniques such as spin coating. Examples of commercially available ionogenic polymers are, for example, polystyrenesulphonate or poly(meth)acrylate. Other polyelectrolytes can readily be obtained synthetically. To ensure dispersion on a molecular scale, it is of course possible again to combine the ionic property and the conjugated property in one compound. In the case of polymers, this is very advantageous. The mixing of two polymers will almost always give rise to phase separation if no special measures, such as the addition of “compatibilizers”, are taken.
A further preferred embodiment of the EL device in accordance with the invention is characterized in that the ionic layer comprises a quaternary amine as the immobile ion. The expression “quaternary amines” is to be understood to mean herein amines which can be obtained from their neutral counterpart by means of an alkylation agent. Consequently, quaternary amines also include quaternized aromatic amines such as the pyridinium compounds. These ions can be provided in the ionic layer, inter alia, by means of an inventive method, referred to as quaternization, which will be explained in greater detail hereinbelow. As a result of the fact that, in this case, the ionic property is not introduced until after the layer has been formed, problems regarding phase separation as a result of the presence of the ions can be precluded. A multilayer device can also be manufactured in this manner.
A particularly suitable embodiment of the EL device in accordance with the invention is characterized in that the ionic layer comprises a conjugated poly(p-phenylenevinylene. Poly-p-phenylenevinylenes are very suitable EL materials. They exhibit a high degree of fluorescence and a satisfactory electroconductivity. The emission spectrum can be varied and readily soluble and processable variants can be obtained by means of substitution, in particular, in positions 2 and 5 of the phenyl ring.
A very suitable, preferred embodiment of the EL device in accordance with the invention is characterized in that the ionic layer comprises a copolymer in accordance with formula (IA/IB) or (II),
wherein the degree of polymerization n+m varies from 5 to 1,000,000, R 1 , R 2 , R 3 , R 4 are chosen to be equal or unequal to —X—R—H or —R—H, R 5 is —R—K 1 A 1 or —R—A 2 K 2 and R 6 is equal to R 5 or to —X—R 5 , wherein R is a branched or unbranched C 1-C 20 alkylene or phenylene-alkylene, X is sulphur or oxygen, K 1 is an ammonium group, A 1 is selected from the group formed by I − , Tos − or other Bronsted-acid anions, A 2 is —CO 2 − or —SO 3 − and K 2 is selected from the group formed by NR 4 + , alkali. These compounds can be synthesized in a simple manner by means of known methods, are soluble and can readily be processed to form amorphous layers in which the ions are dispersed on a molecular scale. Preferably, the fraction m/(n+m) in polymers in accordance with formula (IA/IB) is below 0.15 and above 0.001. Higher values cause the service life to be shortened as a result of an interruption of the conjugation, whereas lower values require an ever longer activating time. In the case of polymers in accordance with formula (II), the fraction m/(n+m) can be varied between 0 and 1, preferably the fraction is greater than 0.001 and smaller than 0.1. The smaller the fraction, the longer the necessary activating time is. At values above 0.1, a substantial improvement is no longer achieved. It has been found that the service life of EL devices prepared by means of polymers (II) is better than that of comparable devices prepared by means of polymers in accordance with formula (IA/IB). It has also been found that, under otherwise equal conditions, the voltage necessary to attain a specific current intensity is lower in devices based on polymers in accordance with formula (II). If polymers in accordance with formula (II) are used, the device can even be operated in air saturated with water vapour for several days.
The presence of non-ionic substituents promotes the solubility. With a view thereto, it is advantageous to choose substituents of unequal length and/or branched substituents. The use of alkylene substituents longer than C 20 hardly leads to a further increase in solubility, whereas the quantity of active material is reduced. The solubility is also determined by the nature of the mobile counterion. For example, polymers in which the tosylate ion is used as the counterion can more readily by dissolved in toluene than the same polymer in which iodide is used as the counterion.
A very advantageous embodiment is characterized in accordance with the invention in that the ionic layer comprises a copolymer in accordance with formula (II), wherein the degree of polymerization n+m varies from 5 to 1,000,000, R 1 is methoxy, R 2 is 3,7-dimethyloctyloxy, R 3 is methoxy and R 6 is [—CH 2 CH 2 N(CH 3 ) 3 ] +I − .
The invention also relates to a method of manufacturing an EL device. In accordance with this method, a first electrode is provided with an ionic layer on which, subsequently, a second electrode is provided, which method is characterized in accordance with the invention in that the ionic layer comprises a compound which can be alkylated, and, before the second electrode is provided, the ionic layer is exposed to an alkylating agent, so that ions are formed in the regions exposed to said agent. An advantage of this method, referred to as quaternization, is that the ionic property is not introduced until the moment when the morphology of the layer has been fixed, thereby precluding phase separation which could occur as a result of the presence of ions. A further advantage is that a multilayer device can be manufactured from a single-layer device in a simple manner by exposing the layer comprising the compound which can be alkylated, that is the precursor layer, to an alkylating agent for a shorter period of time than would be required for complete alkylation, so that the ionic layer and the additional layer are simultaneously formed from the precursor layer. The transition from the alkylated, ionic layer to the non-ionic, additional layer is given by the diffusion profile of the alkylating agent and will be governed by the selected process conditions. Suitable compounds which can be alkylated are compounds whose alkylated product is stable. Dependent upon the strength of the alkylating agent, it is generally required that the compound to be alkylated comprises a lone pair which is associated with an oxygen atom, sulphur atom or nitrogen atom. Particularly suitable representatives of this class of materials are tertiary amines because, in general, they lead to very stable alkylated compounds. The alkylating agent should be selected so that no undesirable side reactions occur. Suitable alkylating agents for amines are, for example, alkylhalides and alkyltosylates. Particularly suitable alkylating agents are the gaseous methyliodide and alkyltosylates which can be dissolved in customary solvents.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a cross-sectional view of a single-layer device in accordance with the invention,
FIG. 2 is a cross-sectional view of a multilayer device in accordance with the invention,
FIG. 3 shows the time-dependence T of the current C (graph A), the brightness (luminance) L (graph B) and the EL efficiency e (graph C), respectively, of a device in accordance with the invention which is operated at a voltage of 22 V, and
FIG. 4 shows the current-voltage characteristic C-V (graph A) and the luminance-voltage characteristic L-V (graph B) of a device in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Synthetic recipe 1
The polymer according to formula (IA/IB)
with R 1 and R 3 equal to 3,7-dimethyloctyl, R 2 and R 4 equal to methyl and R 5 equal to [—CH 2 CH 2 N(CH 3 ) 3 ] + I − and X is O is obtained as follows.
In a 500 ml three-necked flask in nitrogen, 2 g of 2-methyl-5-(3,7-dimethyloctyl)-1,4-chloromethylbenzene (Syncom bv, University of Groningen, The Netherlands) is dissolved in 500 ml of dry tetrahydrofuran (THF). The solution is heated to 30° C. and an equimolar amount of potassium-t-butylate (tBuOK) in 100 ml dry THF is added slowly. The THF is evaporated at 30° C. and 500 ml of cyclohexanone or diglym is added. A quantity of 0.2 mol dimethylaminoethanol and 5 ml di-isopropylethylamine are added to the solution thus obtained. As empirically established by NMR, 0.2 mol dimethylaminoethanol corresponds to a ratio m/(n+m) of approximately 0.1 in the final product. The solution is heated in nitrogen at 140° C. for 20 h. The solution is cooled and the polymer is precipitated in methanol, filtered, washed with methanol and dried in a vacuum. Further purification may be effectuated by dissolving the polymer in THF, to which 0.5 wt % of di-isopropylethylamine is added, and subsequently precipitating it by slowly adding methanol.
Quaternization of the amino group is performed by dissolving the polymer in THF, 1 wt %, and treating it with 3 molar equivalents of methyliodide at room temperature for 2 hours.
The resulting mixture may be purified by precipitation by adding methanol and subsequent drying. The quaternized polymer thus obtained shows a bright green photo- and electroluminescence substantially equivalent to its counterpart without the ammonium group. The polymer is soluble up to approximately 2 wt % in solvents such as chloroform, THF, cyclohexanone.
An alternative quaternization procedure using ethyltosylate reads as follows. The amino-polymer is dissolved in THF (about 1 wt %) and treated with 3 molar equivalents ethyltosylate at room temperature for 2 hours, after which it may be purified by precipitation in methanol. This gives the quaternized polymer with a tosylate counterion, the solubility of which in apolar organic solvents is improved as compared to polymers quaternized with methyliodide. Their electrical and electroluminescent properties are comparable.
Other polymers prepared according to the above procedure are those in which R 1 to R 4 have the above-mentioned meaning and R 5 is selected from the group formed by [—(CH 2 ) 2 NHCH 3 ] + I − , —(CH 2 ) 11 C(═O)ONa, —(CH 2 ) 2 SO 3 Na, with the proviso that anionic polymers are of course not quaternized.
Other polymers according to formula (I) can be obtained by a similar procedure by selection of the proper monomer, primary alcohol or thiol and alkylating agent. The fraction of unconjugated repeating units can be controlled by the amount of primary alcohol or thiol added.
Synthetic recipe 2
The polymer according to formula (II)
with R 2 and R 3 equal to methoxy, R 1 equal to 3,7-dimethyloctyloxy and R 6 equal to [—OCH 2 CH 2 N(CH 3 ) 3 ] + I − is obtained as follows.
In a 500 ml three-neck flask in nitrogen, 1.7 g of 2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-chloromethylbenzene (Syncom bv, University of Groningen, The Netherlands) and 0.3 g of the HCl-salt of 2-methoxy-5-(dimethylaminoethoxy)-1,4-chloromethylbenzene (Syncom bv, University of Groningen, The Netherlands) are dissolved in 500 ml of dried THF. To dissolve the salt 5 ml of di-isopropylethylamine is added. The solution is heated to 30° C. and a solution of 2.5 molar equivalents of potassium-t-butylate (tBuOK) in 100 ml dried THF is added slowly in approximately 5 minutes. This solution is allowed to react for 10 min. Then a solution of 6 to 10 molar equivalents of t-BuOK in 100 ml of THF is added quickly and is allowed to react for 15 to 20 h. After 15 to 20 h the reaction mixture is quenched with 20 ml of acetic acid in 20 ml of THF. The acidic solution is stirred for another 2 h. The volume of the solution is reduced to 50% of the original volume, and 500 ml of methanol/water (5:1) is added slowly to the solution while stirring vigorously. The polymer is filtered, washed with methanol/water (5:1) and dried in a vacuum. To purify the polymer, it is dissolved in THF (0.75 wt %) and fractionated with 500 ml of methanol (3 times). The resultant polymer is soluble in toluene, THF, chloroform up to 1 wt % and the ratio m/(n+m), as determined by NMR, is 0.07.
If desired, the amino group is quaternized by stirring a <1 wt % THF solution of the polymer with 3 molar equivalents of methyliodide for 4 h at room temperature. The quaternized polymer thus obtained shows a bright orange photo- and electroluminescence which is essentially identical to the counterpart without the ammonium group.
Alternatively, ethyltosylate may be used as the alkylating agent.
Polymers which are also prepared according to the above procedure are those in which R 1 is equal to 3,7-dimethyloctyloxy, R 2 and R 3 are equal to methoxy, R 6 is equal to —O—(CH 2 ) p —N(CH 3 ) 3 + and p and q=m/(n+m) are chosen according to the table below.
p
2
2
2
2
2
2
6
6
6
6
2
q
.01
.03
.04
.07
.10
1.0
1.0
.50
.25
.10
.03
A polymer which is also prepared according to the above procedure is characterized in that R 1 is equal to methyl, R 2 is equal to 4,6-dimethylheptyl, R 3 is equal to methoxy, and R 6 is equal to [—OCH 2 CH 2 N(CH 3 ) 3 ] + I − , which polymer exhibits a bright green photoluminescence; the polymer with R 1 equal to hydrogen, R 2 equal to 3-methoxyphenyl, R 3 equal to methoxy, and R 6 equal to [—OCH 2 CH 2 N(CH 3 ) 3 ] + I − also exhibits a bright green photoluminescence. Terpolymers derived from monomers which in homopolymeric form luminesce orange and green, respectively, show a yellow-coloured photoluminescence.
Other polymers according to formula (II) can be obtained by a similar procedure by selection of the proper monomers containing a 1,4-chloromethylbenzene moiety and an alkylating agent. The ratio n/(n+m) can be varied by a variation of the molar ratio of the monomers. Also, by mixing the proper number of monomers, terpolymers and higher are available through this procedure. Characteristic data relating to molecular weight as determined by GPC against polystyrene standards are M n =10 5 and M w /M n =8. If kept in the dark, the shelf life of these compounds is substantially unlimited.
Synthetic recipe 3
The counterions of quaternized polymers according to formula (IA/IB) and (II) can be exchanged as follows. The quaternized polymer is dissolved in THF (<1 wt %) and a mixture (1:1) of acetone and water is added to such an extent that the polymer is about to undergo phase separation. Then the solution is saturated with K 2 CO 3 , stirred for 30 minutes, and precipitated in MeOH/water (1:1). This process is repeated twice. The polymer now has CO 3 2− and/or HCO 3 − as a counterion, which can be replaced by any other counterion X − by adding its acidic form HX to a solution of the polymer in THF/water and gently heating it to remove CO 2 .
Synthetic recipe 4
The synthesis of anionic polymers (II) is illustrated by the synthesis of the polymer in which R 1 is equal to 3,7-dimethyloctyloxy, R 2 and R 3 are equal to methoxy, R 6 is equal to —O—(CH 2 ) 4 C(CH 3 ) 2 COOH.
In a 500 ml three-neck flask in nitrogen, 1.9 g of 2-methoxy-5-(3,7-dimethyloctyloxy)-1,4-chloromethylbenzene (Syncom bv, University of Groningen, The Netherlands) and 0.1 g of 6-(2,5-bischloromethyl-4-methoxyphenoxy)-2,2-dimethylhexanoic acid (Syncom bv, University of Groningen, The Netherlands) are dissolved in 500 ml of dried THF. To dissolve the acid, 1 ml of di-isopropylethylamine is added. The solution is heated to 30° C. and a solution of 2.5 molar equivalents potassium-t-butylate in 100 ml dried THF is added slowly in approximately 5 min. This solution is allowed to react for 15 to 20 h. After 20 min the solution is dark red. After 15 to 20 h the reaction mixture is quenched with 20 ml acetic acid in 20 ml of THF. The acidic solution is stirred for another 2 h. The solution turns bright orange. The volume of the solution is reduced to 50% of its original volume and 500 ml of methanol/water (5:1) is slowly added to the solution while stirring vigorously. The polymer is filtered, washed with methanol/water (5:1) and dried in a vacuum. The polymer thus obtained, contains about 5% of the acid monomer. The polymer is soluble in toluene, THF and chloroform up to 1%.
A polymer which has also been prepared is characterized in that R 6 equals 2,2 dimethylbutoxycarbonic acid which is soluble in acetone, DMSO, cyclohexanone and DMF if a small amount of a tertiary amine, such as di-isopropylethylamine, is added as well.
Exemplary embodiment 1
FIG. 1 shows, schematically and not to scale, a cross-sectional view of an EL device 1 in accordance with the invention, which device can be manufactured as follows. A glass substrate 2 which is transparent to the light to be emitted is provided with a transparent layer of indium tin oxide (ITO) 3 by means of sputtering, said layer having a thickness of approximately 150 nm and a surface resistance of less than 20 Ω/square. This layer is provided, by means of spin coating from a 1 wt. % solution in THF/toluene (1:3), with an ionic layer 4 of a polymer in accordance with formula (IA/IB), wherein R 1 and R 2 are 3,7-dimethyloctyloxy, R 2 and R 4 are methoxy, R 5 is [—CH 2 CH 2 N(CH 3 ) 3 ] + I − , m/(m+n) is 0.08, which polymer is obtained in accordance with synthetic recipe 1. The thickness of the layer is approximately 300 nm. The layer obtained is an amorphous, non-diffusing layer which photoluminesces orange light. Subsequently, a 150 nm thick, gold electrode layer 5 is provided on said layer by means of vacuum deposition. The surface area of the device amounts to approximately 0.9 cm 2 .
The EL device 1 thus obtained is activated by applying a voltage of 22 V across the electrodes, the gold electrode serving as the negative electrode. After some time, orange light is emitted. FIGS. 3A, 3 B and 3 C show, respectively, the time-dependence of the current (A), the luminance and the EL efficiency at the activating voltage of 22 V. The luminance is measured by means of a photodiode and a Keithley 617 electrometer. A photocurrent of 8×10 4 pA corresponds to 100 Cd/m 2 . The EL efficiency is determined in a calibrated “integrating sphere”, in which the overall quantity of light which leaves the device, including via the sides, is measured by means of a calibrated photodiode. FIGS. 3A, 3 B and 3 C show that the performance of the device improves in the course of time, the final EL efficiency being approximately 1.1%. Comparable characteristics are attained at a lower activating voltage, yet, in this case, the time necessary to acquire the same current is longer. The activating time also increases with the layer thickness.
FIG. 4A shows the current (A) as a function of the voltage (V) and FIG. 4 B shows the luminance in arbitrary units as a function of the voltage (V), of a device, immediately after said device has been activated at a voltage of 22 V. It has been found that the device starts to emit light at a voltage as low as approximately 2 V, which corresponds to the band gap of the electroluminescent material.
Subsequently, the device is maintained at a zero voltage for several hours. If, subsequently, a voltage of 22 V is applied, the time-dependence of the current, of the quantity of light and of the EL efficiency are substantially equal to that outlined in FIGS. 3A, 3 B and 3 C.
Exemplary embodiment 2
An EL device is manufactured as described in exemplary embodiment 1, with this difference that for the negative electrode use is made of indium instead of gold. Said indium electrode is provided by applying molten indium to the pre-heated ionic layer by means of a pipette and, subsequently, allowing it to cool in air so that the indium solidifies. The surface area of the negative electrode is approximately 1 cm 2 .
Subsequently, the device is activated at a voltage of 15 V until the brightness is 200 Cd/m 2 . Next, the voltage is reduced to 6 V, as a result of which the brightness decreases to 50 Cd/m 2 . The EL efficiency of the device is approximately 1.0%. Said EL efficiency is substantially equal to that of the EL device comprising the gold electrode of exemplary embodiment 1. If the device is continuously operated at 6 V, the luminance of the emitting areas remains substantially constant. The service life amounts to several days. The device is in direct contact with the outside air during the entire period of time to which this exemplary embodiment relates.
COMPARATIVE EXAMPLE 1
An EL device 1 is manufactured as described in exemplary embodiment 2, with this difference that in the conjugated polymer used in this comparative example, —XR 5 is equal to —OCH 3 . The preparation of this polymer is described in Braun et. al., Synth. Met., 66 (1994). In this case, layer 4 in FIG. 1 is not ionic. The current intensity measured at an applied voltage of 6 V is comparable to that measured in exemplary embodiment 2. However, hardly any light emission is observed. The EL efficiency is less than 0.2%. If the experiment is repeated with a negative electrode of gold, the EL efficiency is even less than 0.01%.
COMPARATIVE EXAMPLE 2
An EL device 1 is manufactured as described in comparative example 1, with this difference that the device is manufactured in nitrogen and, instead of the indium cathode, use is made of a calcium cathode obtained by vacuum deposition. If a voltage of 5 V is applied, orange light is emitted having a brightness of 150 Cd/m 2 and an EL efficiency of 1.0%. The service life of the device thus operated in nitrogen amounts to 100 hours. If such a device is operated under ambient conditions, dependent upon the speed of acting, light emission typically takes place during only approximately ten seconds.
COMPARATIVE EXAMPLE 3
An EL device 1 is manufactured as described in comparative example 1, with this difference that the layer 4 in FIG. 1 consists of a mixture of fully (>98%) conjugated poly[2-methoxy-5-(2,7-dimethyloctyloxy)-1,4-phenylenevinylene] and approximately 1 to 10 mol. % LiBF 4 . The preparation of the polymer is described in Braun et al., Synth. Met., 66 (1994), 75. The polymer exhibits orange photoluminescence. The layer 4 is an ionic layer of which both the anion BF 4 − and the cation Li + are mobile. At high salt concentrations, the layer is scattering.
Under ambient conditions, a voltage of 10 V is applied to the electrodes of the device thus obtained, the indium electrode being used as the negative electrode. The applied voltage causes the color of the layer to change from orange to greenish black in a short period of time, and electroluminescence can be observed only for several hours.
Exemplary embodiment 3
Exemplary embodiment 2 is repeated, with this difference that the polymer used is a polymer in accordance with formula (I), wherein R 1 and R 3 are equal to 3,7-dimethyloctyl, R 2 and R 4 are equal to methyl, R 5 is equal to [—CH 2 CH 2 N(CH 3 ) 3 ] + I − and m/(n+m)=0.04. The device exhibits a comparable performance, however, the light emitted is green and emission is observed from 3 V.
Exemplary embodiment 4
Exemplary embodiment 2 is repeated, with this difference that the polymer used is a polymer in accordance with formula (II), wherein R 1 and R 3 are equal to methoxy, R 2 is equal to 3,7-dimethyloctyloxy, R 6 is equal to [—CH 2 CH 2 N(CH 3 ) 3 ] + I − , and m/(m+n) ranges from 0.01 to 0.25, which polymer is obtained in accordance with synthetic recipe 2. After activating for approximately 2 minutes at 15 V, the device thus manufactured has a luminance of 100 Cd/m 2 at 5 V. The EL efficiency then amounts to 1%. Orange-coloured light is emitted, which is observed already at 2.5 V. The service life of the device is much better than that of corresponding devices in which polymers in accordance with formula (IA/IB) are used and amounts to more than 30 days under ambient conditions.
Comparable results are obtained with the polymer in which R 3 and R 6 have the above-mentioned meaning, R 1 is H and R 2 is 3-methoxyphenyl, which polymer emits green light; and comparable results are also obtained with the polymer in which R 3 and R 6 have the above-described meaning, R 1 is methyl and R 2 is 4,7,7-trimethylheptyl, which polymer emits green light. Devices manufactured by means of terpolymers obtained from monomers whose corresponding homopolymers emit, respectively, green and orange light, emit yellow light.
Exemplary embodiment 5
Exemplary embodiment 4 is repeated, with this difference that the service life test is carried out by accommodating the device in a sealed glass container which is saturated with water vapour. The service life is shorter than that of devices exposed to air, yet it is still more than one week.
Exemplary embodiment 6
An EL device was manufactured as described in exemplary embodiment 2, with this difference that the ITO electrode is structured in such a manner that it comprises 100 independently addressable parallel lines per 5 cm. The polymer used is the same as that of exemplary embodiment 4, the fraction m/(m+n) being equal to 0.07. The layer thickness amounts to approximately 150 nm.
Using a new line each time, it was determined how long it takes to reach a specific luminance at a specific voltage and temperature. At room temperature, it takes 2 minutes, at 50° C. it takes 30 seconds and at 80° C. it takes only 10 seconds. This experiment shows that the device comprises mobile ions whose mobility is governed by temperature.
Subsequently, the device is immersed in cyclohexanone for 24 hours, so that the ionic layer swells while taking up cyclohexanone. The swollen device is subjected to a symmetrical square-wave voltage which is applied across the electrodes with an amplitude of 3 V and a frequency of 100 kHz. At this frequency, no light emission is observed, which shows that the ions are not active at this frequency because their mobility is too low. Subsequently, the frequency is reduced until light emission can be observed, which occurs at 450 Hz. This maximum frequency at which light emission can still be observed is determined in accordance with the same “frequency sweep” at different voltage amplitudes. The results are shown in the following Table.
voltage (V)
frequency (Hz)
3
450
4
1200
5
3500
7.5
8000
10
20000
For comparison, the frequency is at least 1 Hz in the case of a device which is not swollen. These results show that the mobility of the mobile ion can be increased by causing the layer to swell in a solvent, and that the mobility of the mobile ions is governed by the field.
Exemplary embodiment 7
FIG. 2 shows, schematically and not to scale, a cross-sectional view of an EL device 11 which can be manufactured as follows. A precursor layer of the non-quaternized variant of the polymer of exemplary embodiment 2 is provided on a glass substrate 12 coated with an ITO layer 13 , such as used in exemplary embodiment 2. Subsequently, the precursor layer is exposed for some time to an alkylating methyliodide vapour, as a result of which said layer is quaternized to a certain depth, thereby forming the ionic layer 15 . The non-alkylated part of the precursor layer forms the additional layer 14 . Subsequently, an indium-electrode layer 16 is applied to the ionic layer 15 in the manner described in exemplary embodiment 2. A number of devices in which the time during which the precursor layer is exposed to methyliodide vapour is varied, is manufactured in a similar manner. The devices thus obtained are activated for some time at a voltage of 15 V and, subsequently, the luminance and service life are determined at 5 V. The results of this series of measurements are listed in the following Table.
time of treatment
activating at
luminance at 5
service life at
No.
with MeI (min)
15 V (min)
V (Cd/m 2 )
5 V
1
0
10
0
—
2
2
10
0
—
3
5
5
10 ± 10
—
4
23
2
20 ± 10
>2600 h
5
31
2
20 ± 10
>2600 h
6
100
<2
50 ± 10
>2600 h
7
1080
<2
50 ± 10
ca. 48 h
8
—
—
50 ± 10
ca. 48 h
Sample 8 serves as a reference and is manufactured in accordance with exemplary embodiment 2. Clearly, a higher ratio between the ionic layer thickness and the additional layer thickness corresponds to a higher luminance and a shorter activating time. As regards the service life, it has been found that the presence of the additional layer is very advantageous. After 2600 hours, the emitting surface area has decreased by 60%, however, the brightness of the remaining emitting regions is almost as high as before.
Comparable results are obtained if the alkylation process is carried out by exposing the layer to a solution of ethyl-p-toluenesulphonate in acetone for several minutes, allowing the layer to dry, rinsing it with hexane, and drying it.
Exemplary embodiment 8
To manufacture an EL device 11 , a glass/ITO substrate 12 / 13 , as used in exemplary embodiment 2, is provided with an approximately 150 nm thick, additional layer 14 of poly[2-methoxy-5-(2,7-dimethyloctyloxy)-1,4-phenylenevinylene] by spin coating. Subsequently, an approximately 10 nm thick ionic layer 15 is provided by dip coating in a highly diluted (0.01 to 0.1%) solution of the polymer, as used in exemplary embodiment 2, in acetone/cyclohexanone (20:1). Subsequently, an indium-electrode layer 16 is applied to said layer, as described in exemplary embodiment 2. The device thus obtained is activated for several minutes at 15 V. Subsequently, a voltage of 5 V is applied. At said voltage, the luminance is approximately 100 Cd/m 2 , the EL efficiency is approximately 1% and the service life amounts to several weeks. The color of the light emitted corresponds to the photoluminescence of the additional layer. | An organic electroluminescent device whose electroluminescence efficiency is independent of the work function of the cathode material, and whose service life under ambient conditions is excellent without the necessity of taking additional protective measures. These properties are obtained as a result of the fact that an organic layer of the device comprises mobile ions which are compensated by immobile ions in such a manner than the polarity of all mobile ions is the same. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to an apparatus that protects swimming pools and spas from birds that typically land on or near the edge of a spa's spillway into a swimming pool and excrete waste on or near the edge of the spillway.
[0003] 2. Background of the Invention
[0004] Many in-ground swimming pools that are constructed also include a spa feature. Usually, the spa feature is constructed as a separate unit that is slightly higher in elevation, yet it remains adjacent to the swimming pool. When the spa feature is constructed in this manner, the spa usually includes a u-shaped spillway that is carved out of the deck of the spa for water from the spa to escape into the swimming pool. This feature is typically used to prevent water from overflowing on to the spa deck or it can be used as an aesthetic waterfall feature that allows water to spill into the swimming pool.
[0005] By having a u-shaped spillway in the spa, it can be an attraction for birds to use it as a landing area. Birds are notorious for using spa spillways to as an easy way to get access to drinking water from the spa. Normally, it is very difficult for birds to obtain water to drink from the deck of a pool or spa. T his is due to the design of most pools whereby the water level is usually several inches below the deck. However, in a spa spillway, the water level is normally no more than an inch below the spillway. In designs where the spillway is used as a water feature, the water level is typically at the same height as the spillway. Thus, birds are able to land on the spillway and have easy access to drinking water from the spa.
[0006] Unfortunately, as birds land on the spillway to drink water, they are inclined to leave their droppings behind on the spillway. Certainly, it is desirable to either eliminate or discourage birds from landing on the spillways of spas and leaving behind droppings that may not only accumulate on the spillway, but may be transferred into the water of either the spa or an adjacent swimming pool. The present invention eliminates a bird's ability to both land on the spillway of a spa and drink water from the spa. By doing so, the bird is discouraged from remaining near the spillway of the spa and leaving its droppings behind. Furthermore, if the bird does remain for an extended period of time, the present invention prevents any droppings from landing on the spillway area of the spa by acting as a landing area for the droppings.
[0007] U.S. Pat. Nos. 5,845,607 and 5,092,088, as well as U.S. Patent Application Publication 2005/0268393, all disclose various forms of bird deterring devices or covers for bodies of water such as a swimming pool spa. However, none of the prior art patents or publications discloses the apparatus and method as disclosed herein that not only protects the spillway and deck of a spa, but maintains the aesthetic appeal of the spa without unsightly hardware.
SUMMARY OF THE INVENTION
[0008] Broadly, it is an object of the present invention to provide a bird dropping prevention apparatus for use on a spa spillway;
[0009] More particularly, it is an object of the present invention to provide a bird dropping prevention apparatus for use on a spa spillway that comprises a bridge that is secured to the spillway;
[0010] It is a further object of the present invention to provide a bridge with at least three sides that is secured to a spa spillway where two of the sides are substantially perpendicular to each other;
[0011] It is a further object of the present invention to provide a bridge with at least three sides that is secured to a spa spillway where two of the sides have openings that allow water to flow under the bridge;
[0012] It is a further object of the present invention to provide a bridge with at least three sides that is secured to a spa spillway where the openings on the two sides of the bridge may be of various grooved patterns;
[0013] It is a further object of the present invention to provide a bridge with at least three sides that is secured to a spa spillway such that the bridge is adjustable to fit varying spillway surface areas;
[0014] It is a further object of the present invention to provide a bridge with at least three sides that may be constructed from transparent material.
[0015] The description of the invention which follows, together with the accompanying drawings should not be construed as limiting the invention to the example shown and described, because those skilled in the art to which this invention appertains will be able to devise other forms thereof within the ambit of the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view of the spa guard shown using two L-shaped panels and a grooved teeth pattern.
[0017] FIG. 2 is a perspective view of the spa guard as in FIG. 1 showing a transparent view through the top of the guard displaying the grooved teeth pattern on the rear portion.
[0018] FIG. 3 is a perspective view of the spa guard showing the two I-shaped panels in a fully open position.
[0019] FIG. 4 is a top view of the spa guard showing the top side in fully closed and retracted position.
[0020] FIG. 5 is a top view of the spa guard showing the top side in fully open position.
[0021] FIG. 6 is a perspective view of the spa guard shown use on a pool spa.
[0022] FIG. 7 is a side view of the spa guard showing a rectangular groove pattern is on the side panel.
[0023] FIG. 8 is a side view of the spa guard showing a curved wave groove pattern on the side panel.
[0024] FIG. 9 is a side view of the spa guard showing a saw toothed groove pattern on the side panel.
[0025] FIG. 10 is a side view of the spa guard showing a wide wave groove pattern on the side panel.
[0026] FIG. 11 is a perspective view of an alternate embodiment of the spa guard showing a hinged panel on the side of the spa guard.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] By way of one example of many to serve as background in understanding the present invention, a spa spillway guard for preventing bird droppings from landing on spa spillways is described herein.
[0028] As shown in FIG. 1 , a spa spillway guard in the form of a bridge 100 is shown. Generally, the bridge 100 is formed from two L-shaped sections 110 and 120 . The sections 110 and 120 are secured along two horizontal axes 135 by screws 130 and bolts 132 as also shown in FIG. 3 . The sections 110 and 120 can be adjusted along the axes 135 as shown in FIGS. 4 and 5 so that the width of the bridge 100 can conform to the size of a spa spillway 250 as shown in FIG. 6 . It is understood by one skilled in the art that the bridge 100 could also be adjusted along axes that are perpendicular to the axes 135 so that the length of the bridge 100 can conform to the size of the spillway 250 .
[0029] By securing the two L-shaped sections 110 and 120 , the bridge 100 forms three sides 160 , 170 and 180 . Sides 160 and 180 contain notches 140 and 150 as can be seen in FIGS. 1 and 2 . These notches 140 and 150 can be of any suitable shape such as a saw toothed pattern 140 (also shown in FIG. 9 ) or rectangular notches 141 as shown in FIG. 7 , curved notches 142 as shown in FIG. 8 , or a long wave pattern 143 as shown in FIG. 10 . It is understood by one of ordinary skill in the art that the notches can be of any suitable pattern as long as they are large enough to allow liquid to pass through sides 160 and 180 when the bridge 100 is secured to a flat surface.
[0030] In an alternate embodiment as shown in FIG. 11 , a bridge 300 is shown as a single unit with three sides 160 , 170 and 180 . The bridge 300 is shown with panels 190 secured to the sides 160 and 180 of the bridge 300 by at least one hinge 195 . The panels 190 may be opened to provide a full rectangular opening 197 on each side 160 and 180 of the bridge 300 .
[0031] The bridge 100 (or 300 ) is shown in its intended use in FIG. 6 . On many spas, such as the one shown ( 200 ), the spa 200 is constructed at a slightly higher elevation than a swimming pool 260 which is normally adjacent to the spa 200 . The spa typically contains water 220 and has a deck 210 that surrounds the perimeter of the spa 200 in all but one area. The spa 200 of the type shown in FIG. 6 normally includes a spillway 250 that is positioned directly over an area of the swimming pool 260 . The water 220 in the spa 200 is typically set at a level as high, or nearly as high, as the base of the spillway 250 . This allows excess water 220 to spill into the swimming pool 260 due to either splashing from people using the spa 200 , or from drainage of excess water 220 in the spa 200 .
[0032] In most swimming pools 260 or spas 200 , the deck 210 is constructed so that the base of the deck 210 is several inches above the water level 270 or 220 to prevent overflow in case of excess rain or splashing when the pool or spa is in use. However, this is not true of the spillway 250 of the spa 200 .
[0033] It is a well known fact that most domestic birds as the one shown 230 in FIG. 6 are attracted to landing areas near puddles or pools of water so that they can drink the water. If the water level of a swimming pool or spa is high enough relative to the deck of the pool or spa, the deck becomes an ideal area for the bird 230 to land and drink the water from the pool or spa. Because the spillway of the typical is at the same level as the water level in the spa, the spillway is ideal for a bird to land and drink water from the spa. Unfortunately, the bird 230 will leave its droppings behind on the spillway 250 as it drinks the water. Furthermore, if other birds see the bird 230 enjoying a drink of water 220 from the spa 200 , other birds will join the bird 230 on the spillway 250 .
[0034] By securing the bridge 100 or 300 to the spillway 250 of the spa 200 , the bridge 100 or 300 will serve two purposes. First, the bridge 100 or 300 precludes the bird 230 from landing directly on the spillway 250 . Thus, should the bird 230 remain long enough on the top side 170 of the bridge 100 or 300 , any droppings will fall on the top side 170 of the bridge 100 or 300 . Secondly, because the top side 170 of the bridge 100 or 300 is several inches above the spillway 250 of the spa 200 , the bird 230 is incapable of drinking the water 220 in the spa. Thus, the bird 230 is discouraged from remaining on the area near the spillway 250 and leaving its droppings behind on the deck 210 or the bridge 100 or 300 . When the bridge 100 or 300 is properly secured to the spillway 250 , the water 220 from the spa 200 may flow 240 unimpeded directly through the notches 140 on the first and second sides 160 and 180 of the bridge 100 or 300 and into the swimming pool 260 . The notches 140 also serve to prevent the bird 230 from landing on the spillway 250 under the bridge 100 or 300 . However, it is understood by one of ordinary skill in the art that even without the notches 140 , 141 , 142 , 143 or the panel 190 , most birds 230 will be discouraged from landing on the bridge 100 or 300 due to their inability to drink from the water 220 , nor, if the bird 230 is large enough, will it be able to fit under the bridge 100 or 300 and land on the spillway 250 of the spa 200 .
[0035] With regard to the bridge 100 or 300 , it is preferable that the bridge 100 or 300 be constructed from transparent material as shown in FIG. 2 such as urethane or plastic for aesthetic purposes so that the continuity of the view the deck 210 or the spillway 250 is not compromised. It is also preferable that the height of sides 160 and 180 of the bridge 100 or 300 be constructed so that the top side 170 of the bridge 100 or 300 is at the same level as the deck 220 of the spa 200 so that the surface area of the perimeter of the deck 210 is continuous.
[0036] While the apparatus for practicing the within inventive method, as well as said method herein shown and disclosed in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated, it is to be understood that it is merely illustrative of the presently preferred embodiment of the invention and that no limitations are intended to the detail of construction or design herein shown other than as defined in the appended claims.
[0037] Although the invention has been described in detail with reference to one or more particular preferred embodiments, persons possessing ordinary skill in the art to which this invention pertains will appreciate that various modifications and enhancements may be made without departing from the spirit and scope of the claims that follow. | An apparatus that protects swimming pools and spas from birds that typically land on or near the edge of a spa's spillway into a swimming pool and excrete waste on or near the edge of the spillway. | 4 |
This application is a continuation of prior application Ser. No. 10/183,084 filed Jun. 27, 2002 now U.S. Pat. No. 7,280,645, which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention is directed to a method of associating multiple prepaid cards with a single account, and more particularly, to a method of linking multiple prepaid cards to a predetermined amount of minutes such that each card can simultaneously draw minutes from the same account.
BACKGROUND OF THE INVENTION
Many people use prepaid telephone calling cards as an easy and reliable way to make long distance telephone calls from any telephone. People appreciate the convenience of the cards as well as the benefit of knowing beforehand how much a call will cost per minute. Another benefit of prepaid cards is that because the cards have a defined limit (e.g., typically in terms of minutes or dollars), people know that in the case of theft, the resulting loss to the person is readily discernible and limited to the remaining balance on the prepaid card.
One drawback to prepaid cards is that each card is treated like a separate account from the perspective of the prepaid card provider. As such, people who wish to provide multiple people with cards must purchase separate cards and track each card's usage separately. Since prepaid cards providers do not provide call detail records, it is not possible to discern any information about the prepaid card user other than the fact that the minutes have been depleted. Typically, the current solution has been to provide traditional calling cards to those people. However, there are a number of disadvantages to traditional calling cards.
One disadvantage is that the typical per minute charge for calling cards is significantly higher than the per minute charge for prepaid cards. A second disadvantage is that the calling card usually has no preset limit either in terms of dollars or minutes. As such, if someone abuses the privilege of having the card or the card is stolen, significant charges can be made to the card. Finally, using a calling card presupposes a long-term commitment that results in monthly or periodic billings. Again, the costs attributable to the calling cards are unknown and not easily controlled. There is a need for multiple prepaid cards that can be associated with a single account and can be used simultaneously.
SUMMARY OF THE INVENTION
The present invention is directed to a set of multiple prepaid calling cards that are associated with a single account. A predetermined amount of minutes is associated with the set of cards. Cards within the set can be used simultaneously and extract minutes from the minutes in predetermined increments. Each card can use the same Personal Identification Number (PIN) or each card can have its own unique PIN. In some instances, any card in the set can recharge the account, (i.e., add more minutes to the account), or in some embodiments, only a control card can add minutes to the account.
In the case of each card having a different PIN, rules can be established for each card. Limits can be placed on a particular card with respect to minutes used in a defined time period (e.g., hour, day or week). Record detail can also be provided for each card to determine number of calls made, duration of calls, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example and not limitation in the accompanying figures in which like reference numerals indicate similar elements and in which:
FIG. 1 illustrates an exemplary set of multiple prepaid cards in accordance with the present invention;
FIG. 2 illustrates a block diagram of a Point of Sale (POS) set-up for activating a set of multiple prepaid cards in accordance with the present invention;
FIG. 3 illustrates a network architecture in which a call can be initiated using one of the multiple prepaid cards in accordance with the present invention;
FIG. 4 illustrates a schematic block diagram of the prepaid card account system of FIG. 3 in more detail;
FIGS. 5A and 5B illustrate a flow chart in which a user of one of the multiple prepaid cards makes a call in accordance with the present invention; and
FIGS. 6A-6C illustrate a flow chart in which multiple prepaid card users associated with a single prepaid card account can simultaneously extract minutes from the account in accordance with the present invention.
DETAILED DESCRIPTION
The present invention is directed to a method for associating multiple prepaid cards with a single account. FIG. 1 illustrates an exemplary set of prepaid cards in accordance with the present invention. Included with the set of prepaid cards is a sales card 102 . A merchant (i.e., Point of Sale (POS)) uses the sales card 102 to validate and activate the card set upon purchase. The sales card 102 includes a control number 104 that is used by the merchant to activate the card set. A bar code 106 representation of the control number may also be included on the sales card 102 .
The set of prepaid cards 108 - 114 upon activation may be distributed by the purchaser to a group of people for their individual use. Each prepaid card 108 - 114 includes a telephone number (e.g., a 8YY number), which when dialed, allows the user to place a call upon validation of the card and the availability of minutes as will be described in detail hereinafter. Each card also includes an account number 118 and a PIN 120 . Each card may include the same account number and PIN or different account numbers and/or PINS.
FIG. 2 illustrates a block diagram of a POS setup for activating the prepaid card set. Upon purchase of a multiple prepaid card set, the control number of the sales card 102 is inputted into a POS terminal 204 . The POS terminal 204 may be associated with a cash register (not shown) used by the merchant or may be part of a kiosk used for dispersing prepaid cards. The control number may be scanned by the POS terminal via the barcode or may be typed in using a keypad (not shown).
Once the control number is entered, it is stored in a database 206 associated with the POS terminal 204 . The database 206 may be used by the merchant to keep track of sales of the prepaid cards for inventory purposes and to notify the prepaid card supplier of a sale so that the card can be activated. The control numbers are communicated to the prepaid card supplier over a communication network 210 . It is to be understood by those skilled in the art that the control numbers may be communicated at the time of purchase, periodically (e.g., every six hours) or at an established time of day (e.g., overnight).
The POS terminal 204 connects to the communication network 210 via a modem 208 that uploads the control numbers and communicates them to a prepaid card supplier server 212 . The prepaid card supplier server activates the associated prepaid card set and establishes an account for the prepaid card set. The account includes the number of cards in the set, the number of minutes associated with the account, and any limits that may be placed on the account. It is to be understood by those skilled in the art that limits applied to any or all of the cards may be established at the time of purchase or at a later time by one of the prepaid card users as will be described in detail hereinafter.
Referring to FIG. 3 , there is shown network architecture for initiating a call using one or more of the multiple prepaid cards associated with the same account in accordance with the present invention. A communication network 11 provides telecommunication services, such as standard voice services via standard phones 12 and 13 , pay phone 14 , international voice service 15 , cellular service 16 , packet telephone service 17 and Internet service 18 . Standard voice services carried over communication network 11 , such as Plain Old Telephone Service (POTS), long distance services, voice-messaging services, and “toll-free” services are accessed through a Local Exchange Carrier (LEC) in a well-known manner, or by direct connection to the communication network 11 .
Communication network 11 includes a Prepaid Card Account System (PCAS) 20 . PCAS 20 processes and stores all information pertaining to each prepaid card account including, but not limited to, the number of cards per a given account, the number of available minutes, validation information (e.g., PINs for each card), as well as any account profiles. Account profiles may include certain call restrictions which may be defined by time limits, geographical boundaries, number of calls in a predefined period of time or any other parameter defined by the establisher of the account or the prepaid card provider.
FIG. 4 illustrates the PCAS 20 in more detail. PCAS 20 includes a validation system 30 , an Interactive Voice Response (IVR) unit 36 , a recording and billing processor 31 , an account database 33 and optionally a call detail records database 34 . The IVR unit 36 announces to the user a series of options for initiating a prepaid call via the validation system 30 . Among the provided options is a request for the user's account number and PIN. Validation system 30 receives the account number and PIN entered by the prepaid card user. The validation system 30 queries the account database 33 to determine if the account number and PIN are valid using known techniques. The account database 33 is also queried upon validation to determine if any calling restrictions apply to the account. In accordance with the present invention, the validation system 30 is capable of simultaneously or contemporaneously validating multiple prepaid cards associated with the same account.
Recording and billing processor 31 includes a timer 32 for recording the length of a given call and also for distributing minutes to one or more of the multiple prepaid cards as will be described in detail hereinafter. Recording and billing processor 31 is also able to determine per minute charges for calls (e.g., international calls either originating or terminating in a foreign country). The per minute charges are then used to “calculate” minute usage. For example, for a standard domestic call, the per minute charge may be 5 cents per minute. However, a call to Great Britain may be 25 cents per minute. As such, an international minute in this context is equivalent to 5 domestic minutes (e.g., five 5 cent per minute minutes equals one 25 cent per minute).
Call detail records database 34 stores billing records relating to each multiple prepaid card account, both in terms of the account as a whole and records relating to each individual card. Such information may be provided to the prepaid account holder for purposes of auditing the call patterns for a particular card user.
FIGS. 5A and 5B illustrates the steps required for a user of one of the multiple prepaid cards associated with a single account to place one or more calls and, in particular, the scheme used to allocate minutes to a user of a multiple prepaid card account in accordance with an embodiment of the present invention. A user of one of the multiple prepaid cards (also referred to as a caller) enters the access number for the prepaid service provider (step 502 ). The access number may be a toll free number such as an 8YY number. An Interactive Voice Response (IVR) unit 36 announces to the caller a series of options in which each option is associated with a prompt. Such prompts may include a selection of language in which any additional instructions are provided and a request for the caller to provide his account number and PIN (i.e., login information).
The caller enters the account number and PIN associated with his particular card (step 504 ). The PIN may be a series of numbers or alphanumeric characters of a particular length (e.g., between 8-12 characters). It is to be understood by those skilled in the art that the PIN for each card in a particular multiple card account may be the same or different. A determining factor of which scheme is used would depend on the necessity to provide account activity on a per card basis. The validation system 30 then determines if the received login information is valid by looking up the login information in the account database 33 (step 506 ). If the login information is not valid, further service is denied (step 508 ).
If the login information is valid, the account database 33 is further queried to determine if the caller's card is subject to any call restrictions (step 510 ). As indicated above, examples of call restrictions may include restrictions on the hours of the day in which calls can be made (e.g., between 9 AM and 6 PM), days of week, restricted call destinations, restricted lengths of calls restricted call origination locations, etc. If call restrictions apply to the caller's card, any succeeding calls are monitored to ensure that the restrictions are maintained. If no card restrictions are applicable, processing of the card continues.
The IVR unit 36 then prompts the caller to enter the destination telephone number for the call that he wishes to complete (step 514 ). The caller may enter the telephone number by using the keypad associated with the caller's telephone to transmit Dual Tone Multi-Frequency (DTMF) signals, by speaking the telephone number if the PCAS includes voice recognition capabilities, or by typing the number on a computer keyboard if the call is being made over a packet network.
Once the PCAS 20 receives the telephone number, the PCAS determines if the number is valid (step 516 ). Validity of the telephone number may be determined in light of the call restrictions applicable (e.g., the caller may not be able to make any or certain international calls), whether the received number is in fact a valid telephone number or in light of other call restrictions (e.g., time of day, number of minutes used by caller, etc.). In some embodiments of the present invention, in addition to determining validity of the received telephone number, the PCAS 20 may also determine a per minute charge applicable for the particular call. While it is common in the current art for minutes attributed to a prepaid card to be consistently priced (e.g., 5 cents per minute), it is conceivable that different per minute charges could be applied based on the destination of the call. Such pricing would be expected, in particular, if the card was authorized for both domestic and international calls. Alternatively, a different per minute charge may arise if the call originates from a location outside of the U.S.
In either embodiment, once the destination telephone number is received, the PCAS 20 determines the number of minutes available to the caller and informs the caller of the available minutes (step 520 ). Again; the minutes communicated to the caller may vary depending upon the restrictions applicable to the caller. For example, the caller may be entitled to use all available minutes attributed to the account (e.g., 200 minutes). However, if the caller has a length of call restriction, the maximum number of minutes for the call may be significantly smaller (e.g., 30 minutes).
Assuming that there are minutes attributed to the account and no restrictions are applicable to the call, the destination telephone number is used to route the call and the caller is connected to the called party if the called party answers the call (step 522 ). Upon connection of the call, a predetermined amount or bucket of minutes from the account is allocated to the caller's call. For example, the minutes could be allocated in 10-minute increments. As will be described in more detail hereinafter, the allocation of minutes is required to ensure that in the case of simultaneous calls made by multiple user's of a single multiple prepaid account, each card user is able to receive minutes for their calls and the minutes are not monopolized or depleted by a single card user.
The PCAS 20 periodically checks to determine if a given bucket of minutes have been depleted by the caller (step 526 ). Once a bucket of minutes are depleted, the PCAS 20 determines if there are minutes left in the account (step 528 ). If no minutes remain in the account, the caller is notified that the account minutes need to be replenished (step 530 ). Depending on the particular embodiment of the present invention, the caller may be able to replenish the minutes by providing the appropriate information to the PCAS 20 (e.g., authorize the PCAS 20 to bill a revolving account or credit card account). Alternatively, only limited card users within the account may be able to replenish the account. In such an event, the authorized card user would be notified.
If the particular bucket of minutes is not depleted, a check is performed to determine if the call has been completed (step 532 ). If the call is not completed, steps 526 - 530 are repeated. If the call is completed, a check is made to determine if there are any minutes remaining in the account balance (step 534 ). If minutes are not available, the caller is notified that the account balance needs to be replenished (step 536 ). If there are minutes available, the caller is prompted by the IVR unit 36 to determine if the caller wishes to make another call (step 538 ). If the caller does not wish to make another call, any remaining allocated minutes are returned to the account balance and the interaction between the caller and the PCAS 20 is ended (step 540 ). If the caller wishes to make an additional call, steps 514 - 540 are repeated.
FIG. 6 illustrates how the scheme described above is used to allocate and monitor account usage when more than one card associated with the account are in use simultaneously. As described above, a first cardholder dials the access number for the prepaid card service provider (step 602 ). The first cardholder enters the account number and PIN associated with his particular card (step 604 ). Next; a check is performed by PCAS to determine if the card is valid (step 606 ). If the card is not valid, service is denied (step 608 ).
If the card is valid, the first cardholder is prompted to provide the destination telephone number for the call that he wishes to make (step 610 ). Provided that the telephone number is not subject to any restrictions associated with the first cardholder, the PCAS determines the per minute charge for the call (step 612 ). As indicated above, some calls may be priced differently depending either upon the origination of the call (e.g., overseas or international origination) and the destination of the call (e.g., international call). Regardless of whether the account is measured in terms of minutes or dollars, the cost for the particular call may have a different impact on the account balance.
Once the determination is made, the PCAS determines whether there are adequate minutes available in the overall account to complete the call (step 614 ). The determination of adequate minutes is based on the bucket of predetermined minutes that will be allocated to the first cardholder. If there are not adequate minutes to allocate a bucket, the cardholder is notified of the need to replenish minutes in the account (step 616 ).
If there are adequate minutes in the account, the PCAS allocates a bucket of predetermined minutes (e.g., 10 minutes) to the cardholder and connects the call (step 618 ). The bucket of minutes is then subtracted from the overall account balance (step 620 ). The PCAS then monitors additional call requests from other cardholders (step 622 ). If no additional call requests are received, the PCAS continues to process the call for the first cardholder (step 624 ).
If call requests are received from additional cardholders, the PCAS validates login information (i.e., account number and PIN) for each additional cardholder (step 626 ). Once validated, the destination telephone number is received from each additional cardholder (step 628 ). The per minute charge is then calculated for each call based on the origination location of the call and the destination telephone number (step 630 ). For each call request, a determination is made as to whether there are adequate minutes available in the overall account to complete the calls (step 632 ). This determination is made on a call-by-call basis. If there are not adequate minutes to complete any of the calls, those call holders are notified of the need to replenish minutes in the overall account (step 634 ).
If there are adequate minutes available for the additional call requests, a bucket of predetermined minutes is allocated for each call request (step 636 ). Each bucket of minutes allocated to an additional cardholder is then subtracted from the overall account balance (step 638 ). The PCAS then monitors each call to determine if a bucket of minutes for a particular call has depleted or is close to depletion (step 640 ). If none of the buckets of minutes has been depleted, the PCAS continues to monitor all of the ongoing calls (step 642 ).
If a particular cardholder depletes his bucket of minutes, a determination is made as to whether there are adequate minutes remaining in the overall account to allocate an additional bucket of minutes to the cardholder (step 644 ). If there are not adequate minutes remaining in the account, the cardholder is notified of the need to replenish minutes in the account (step 648 ). If there are adequate minutes, another bucket of a predetermined number of minutes are allocated to the cardholder (step 650 ). The bucket of minutes is then subtracted from the overall account balance (step 652 ).
The PCAS also monitors each ongoing call to detect call completion (step 654 ). If no calls are completed, the goes back to step 640 . If a call is completed, remaining minutes allocated to the cardholder are returned to the overall account balance (step 656 ). Next, a determination is made as to whether the particular cardholder wishes to make another call (step 658 ). If the cardholder wishes to make another call, the process is repeated beginning at step 628 . If the cardholder is not making additional calls, the PCAS continues to monitor all other ongoing calls (step 660 ).
As indicated above, in some embodiments of the present invention, each card associated with a particular account is assigned a unique PIN. As such, monitoring of each particular card's activity is possible. This is particularly useful when the cards are distributed for business purposes. In addition to the ability to provide call detail records for each individual card, one of the cards in the account can be designated as a control card. As such, the control card can be provisioned with features that are not available to the other cards associated with the account. For example, in some instances the control card may be the only card capable of replenishing minutes to the prepaid card account. In addition, the control card may be the only card capable of placing call restrictions on one or more of the other prepaid cards associated with the particular account.
In an alternative embodiment, the PCAS may include a restriction directed to overall minute usage permitted by one or more of the cards in the account. For example, it may be determined that the overall minute balance can be used by any of the cardholders and that there is no minute usage limit. As such, one cardholder could theoretically deplete all of the minutes in the master account. In another scenario, each card may be assigned a maximum minute usage. The minute allotments may be equally divided among the cardholders or vary from card to card.
Another variation would limit the amount of minutes to be used by a cardholder in a given duration. The duration could be defined per call (e.g., 30 minutes maximum), a daily maximum (e.g., 100 minutes per day) or a weekly maximum (e.g., 500 minutes per week). The specified duration and limit can be defined using the control card for the particular account based on business or other needs (e.g., family needs in the case of a family account).
While the present invention has been described in connection with the illustrated embodiments, it will be appreciated and understood that modifications may be made without departing from the true spirit and scope of the invention. It is to be understood that the particular embodiments shown and described by way of illustration are in no way intended to be considered limiting. Therefore, references to details of particular embodiments are not intended to limit the scope of the claims, which in themselves recite only those features regarded as essential to the invention. | A set of multiple prepaid calling cards that are associated with a single account is disclosed. A predetermined amount of minutes is associated with the set of cards. Cards within the set can be used simultaneously and extract minutes from the account in predetermined increments. Each card can use the same Personal Identification Number (PIN) or each card can have its own unique PIN. In some instances, any card in the set can recharge the account, (i.e., add more minutes to the account), or in some embodiments, only a control card can add minutes to the account. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] When practicing a sport, most individuals will continually shoot at an empty goal. To be successful in honing their shooting skills, players need to practice shooting on a goal in as close to game situations as possible. The more game-like the shooting practice, the better the overall practice will be for the player's development. Most players find the time to practice on their own in their back yard or nearby park. When practicing shooting on a sports goal, the need for a goalkeeper is vital to ensure the game-like setting. When a player doesn't have the benefit of another player to act as goalkeeper the practice is less than ideal. Players soon become complacent in shooting at self targeted areas and thus fail to develop their full shooting accuracy potential.
[0005] When players have no defined target area they quickly become complacent in their self defined scoring target, thus they are prone to rapid deterioration in shooting at a defined area. Most products have a common theme, strike the target not the game goal netting as in a real game. The products on the market today lack the ability to be adjusted to the player's specific needs for the desired outcome of the practice. Several patents have been issued for products that meet some of these needs. Players are in need of constant feedback of their training progress, and will benefit from the immediate feedback, both positive and negative.
[0006] In patent USD537489S to McAdams et al., issued February of 2007, the product identifies only four target areas for the player to aim at. These areas are adjustable to a limited set of variables. The targets themselves are just that, targets, in effect by striking them a puck, in this case, is blocked from continuing freely into the goal. While the hanging sets of targets can be moved to several places along the crossbar, there are a limited number of targeted areas the player can select with this device. The targets seemed to be connected with a piece of material that has as it's only purpose, as a connector between the upper and lower targets, thus blocking off areas of the goal that are not deemed a target. These fixed targets, are locked in place and can not be altered to fit all the needs of the player.
[0007] In U.S. Pat. No. 6,695,724B2 to Birss, issued February of 2004, this application's theme is to hit something other than the back of the goal netting. The target nets are different in that they are spring loaded and flex back to the designated area for training purposes after being struck by the puck. These movable small goal nets can be relocated to different areas along the hole of the sports goal to fit the needs of the player, but are very limited in their overall flexibility in meeting the varies needs of the player. The puck must still strike the target, not the goal netting, which is what the player wants to practice, in order to be deemed a successful shot for training purposes.
[0008] In U.S. Pat. No. 0,214,331A1 to Talafous, issued in September of 2008, magnets have been inserted into the target pad itself, this form of attaching device allows the pad to become dislodged from the goal each time the pad, or target, is struck. The pads become the target of the players aim, not the actual goal itself as in a game situation. When these targets are are struck it causing the player to stop and reset them thus disrupting the normal flow of a game like training session.
[0009] In this application, as illustrated in the U.S. Pat. No. 7,811,184B2 to Siefker, issued in October of 2010, the drawing shows the device as an alterable piece of fabric like material that can be folded, in effect, to change the shape of the training device. These alterations are hindered by the need for the fabric like material to be stretched to the goal posts, in order to gain their support from the attaching methods. Said material does not have the ability to keep its shape without being attached or stretched to the goal. The fabric is prone to rapid deterioration due to repeated ball strikes, and tears at the attachment points due to repeated stresses of said strikes. The material has not impact deadening properties, to lesson the bounce back probility, thus causing danger to the players.
[0010] With the U.S. Pat. No. 5,634,640 to McCarrel, issued June of 1997, we see the identification of several desirable scoring areas designated by the flags in this application. The training effect is gained by striking the targeted flag which hangs in front of the goal. The fabric pieces hanging down from the cords are limited in their ability to be adjusted to different configuration. The fabric material can be easily affected by winds and deterioration due to ball strikes. The cords are exposed to possible ball strikes that may cause confusion as to whether the target or the cord as struck with the shot.
BRIEF SUMMARY OF THE INVENTION
[0011] A reconfigurable sports training pad system is designed to improve an individual's scoring accuracy. This is accomplished through repetitive shooting at specified targeted scoring areas which are deemed to have the highest probability of scoring. The targeted scoring areas are created by effectively blocking off non-targeted areas of an existing goal, while allowing scoring to be accomplished only in the specific targeted scoring areas. Success is accomplished through muscle memory and repetitive scoring in the defined targeted areas.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0012] FIG. 1 : is a forward perspective view of the invention 10 .
[0013] FIG. 2 : is a rear perspective view of the invention 10 .
[0014] FIG. 3 : is a rear perspective view of the invention 10 omitting component 48 envelope for illustrative clarity.
[0015] FIG. 4 : is a rear perspective detail view of the invention 10 omitting component 48 envelope for illustrative clarity.
[0016] FIG. 5 : is a forward perspective view of the invention 10 component 60 half-bar support assembly only.
[0017] FIG. 6 : is a rear perspective view of the invention 10 component 60 half-bar support assembly only.
[0018] FIG. 7 : is a perspective view of the invention 10 component 44 hanger support only.
[0019] FIG. 8 : is an exploded view of the invention 10 and omitting multiple components for illustrative clarity.
[0020] FIG. 9 : is a perspective view of the invention 10 component 46 small attaching device only.
[0021] FIG. 10 : is a perspective view of the invention 10 component 32 large attaching device only.
[0022] FIG. 11 : is a front view of an alternate embodiment of the invention 10 component 58 full-bar support assembly only.
[0023] FIG. 12 : is a detail section view of the invention 10 along line 12 - 12 in FIG. 2 .
[0024] FIG. 13 : is a front view of an alternate embodiment of the invention 10 component 70 expandable-bar support assembly only.
[0025] FIG. 14 : is a rear view of an alternate embodiment of the invention 10 .
[0026] FIG. 15 is a rear view of an alternate embodiment of the invention 10 .
DETAILED DESCRIPTION OF THE INVENTION
[0027] A sports pad 56 is constructed of three major parts, the envelope 48 , the rigid backing insert 40 , and the impact absorbing insert 38 , as illustrated in FIG. 1 , 3 , 8 , and 12 . FIG. 8 shows the impact absorbing insert 38 that is a material that can withstand repeated impacts, and has the ability to retain its shape without rapid deterioration. The impact absorbing insert 38 has the ability to be configured in a variety of shapes and sizes. FIGS. 3 , 8 , and 12 the rigid backing insert 40 is constructed of a rigid material that can be assembled in various ways, not limited to welding and or fastening together with nuts, and bolts, to provide support and overall shape for said sports pad 56 . The third member of the sports pad assembly is the envelope 48 , which is a sewable, tear resistant material that has pass-thru holes 50 , 52 for the attaching devices to join the said pad system to the half-bar support assembly. The small attaching device 46 and the hanger support 44 are attached to the rigid backing insert 40 and are located to provide stable support of said sports pad 56 . These parts are protruding thru the envelope 48 when the parts pass thru holes 50 , and 52 are properly aligned. The parts pass-thru holes 50 , and 52 have reinforced stitching 54 to provide additional tear resistance. The envelope 48 is sealed by the use of the envelope flap 68 and is held closed with the use of a hook and loop fastening system 64 . FIG. 7 illustrates the hanger support 44 that attaches to the rigid backing insert 40 . FIG. 9 illustrates the small attaching device 46 that also attaches to the rigid back insert 40 , to provide addition support for the said pad system. The rigid backing insert 40 with the hanger supports 44 and small attaching devices 46 affixed, is designed to be inserted into the envelope 48 along with the impact absorbing insert 38 , making sure the parts pass-thru holes 50 . and 52 , are properly aligned. FIGS. 1 , 2 , 3 , 4 , 5 , 6 , and 8 ; illustrate the half bar support structure 60 . The primary components of the half bar support structure 60 are listed as follows. The S-bracket 14 acts as the connector between the sports goal 12 and the half-bar support structure 60 through the use of the large attaching devices 32 , FIG. 4 . The tube 42 connects the s-bracket 14 to the connector bar 36 and is reinforced by the spreader bar 34 , FIG. 3 . The connector bar 32 also acts to allow a second half bar support structure 38 to be connected to the first half bar support structure 60 .
[0028] In FIG. 7 , the said pad system 10 is attached to a sports goal 12 in different configurations, meeting the changing needs of the player. Said pad system 10 can be moved to different areas on a sports goal 12 that have the highest probability of scoring. Sports pads 56 are not limited in size or shape and can be constructed to meet specific needs of the player.
[0029] In FIGS. 11 , 13 - 15 addition embodiments are illustrated. The full bar support structure 58 , FIGS. 11 , and 13 may be constructed as a one or four piece unit. The full bar support system 58 may also be constructed as a two piece unit, FIG. 15 . The sports pad 56 may be constructed in a variety on shapes and sizes to meet the needs of the player, FIGS. 14 , and 15 .
DESCRIPTION LIST
[0000]
10 : is the overall invention.
12 : is the goal.
14 : is the s-bracket.
16 : is the connector bar hole.
18 : is the s-bracket hole
20 : is the hanger support hole.
22 : is the hanger support/rigid back insert mate hole.
24 : is the rigid back insert hole.
26 : is the large attaching device hole.
28 : is the small attaching device hole.
30 : is the small attaching device hole/rigid back insert mate hole.
32 : is the large attaching device
34 : is the spreader bar.
36 : is the connector bar.
38 : is the impact absorbing insert.
40 : is the rigid back insert.
42 : is the tube.
44 : is the hanger support.
46 : is the small attaching device.
48 : is the envelope
50 : is the hanger support pass-through envelope hole.
52 : is the small attaching device pass-through envelope hole.
54 : is the reinforcing stitching.
56 : is the sports pad.
58 : is the full-bar support assembly.
60 : is the half-bar support assembly.
62 : is the spreader tube.
64 : is the hook and loop fastener.
68 : is the envelope flap.
70 : is the expandable-bar support assembly.
Note: Fasteners are intentionally omitted from all views for illustrative clarity and are assumed, by those knowledgeable in the arts, as obvious and necessary but nondisplayed features for use in fastening invention 10 components together. | A reconfigurable sports training pad system is designed to be attached to an existing sports goal to increase the accuracy of scoring through muscle memory and positive and negative reinforcements accomplished through repetitive shooting. | 0 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/250,439 filed Oct. 9, 2009.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention relates to an engine having axial combustion chambers and axial pistons connected to side power output shafts.
[0005] 2. Description of the Related Art
[0006] Various engine designs are known. For example, U.S. Pat. No. 6,769,384 discloses a radial piston engine wherein power is transferred such that the power take-off is truly balanced in that the piston runs truly parallel to the cylinder walls. This radial engine reduces wear of the cylinders and piston rings, provides improved gas mileage due to the reduced piston drag, and produces greater torque than other engine designs. Other engine designs are shown in U.S. Pat. Nos. 3,319,416 and 1,419,693.
[0007] U.S. Patent Application Publication No. 2008/0149052 shows and describes an engine having axially opposed cylinders.
[0008] However, there is still a need for further improvements in an inline piston engine: (i) where power take-off is truly balanced such that the piston runs truly parallel to the cylinder walls, (ii) that provides improved gas mileage by reducing piston drag, and (iii) that produces greater torque.
SUMMARY OF THE INVENTION
[0009] The foregoing needs are met by an engine according to the present invention. The engine includes a cylinder defining an interior space of the cylinder; a first piston that reciprocates in the interior space of the cylinder wherein the first piston has a first end forming a first piston head; a first piston rod attached to the first piston at a second end of the first piston opposite the first end of the first piston; a second piston that reciprocates in the interior space of the cylinder, wherein the second piston has a first end forming a second piston head; a second piston rod attached to the second piston at a second end of the second piston opposite the first end of the second piston; a first connecting rod connected to the first piston rod and coupled to a first power output shaft; and a second connecting rod connected to the second piston rod and coupled to the first power output shaft. The first piston head and the second piston head define a combustion chamber in the cylinder between the first piston head and the second piston head, and the first piston head and the second piston head move away from each other on a first power stroke of the first piston and a second power stroke of the second piston.
[0010] The first piston rod can be attached to the first piston such that the first piston rod extends diametrically across the second end of the first piston, and the second piston rod can be attached to the second piston such that the second piston rod extends diametrically across the second end of the second piston. A fuel intake port can be in fluid communication with the interior space of the cylinder, and an exhaust port can be in fluid communication with the interior space of the cylinder, wherein the fuel intake port and the exhaust port are located in opposite ends of the cylinder.
[0011] In one version of the engine, a third connecting rod is connected to the first piston rod and coupled to a second power output shaft, and a fourth connecting rod is connected to the second piston rod and coupled to the second power output shaft. In another version of the engine, the engine includes a third piston having a third end forming a third piston head wherein the first piston rod is attached to the third piston at a second end of the third piston opposite the first end of the third piston; and the engine includes a fourth piston having a fourth end forming a fourth piston head wherein the second piston rod is attached to the fourth piston at a second end of the fourth piston opposite the first end of the fourth piston.
[0012] In another version of the engine, the engine includes a first cylinder head at a first end of the cylinder; and a second cylinder head at a second end of the cylinder. The third piston moves toward the first cylinder head during the first power stroke of the first piston, and the fourth piston moves toward the second cylinder head during the second power stroke of the second piston. The engine can include a housing, a first end plate sealing a first open end of the housing, and a second end plate sealing a second open end of the housing. A section of the first end plate forms the first cylinder head, and a section of the second end plate forms the second cylinder head. The housing can comprise a pair of housing sections, and the pair of housing sections can be connected by a bearing wherein the first power output shaft rotates in the bearing.
[0013] The engine can include a cylinder block that divides the combustion chamber in the cylinder into a first combustion chamber volume adjacent the first piston head and a second combustion chamber volume adjacent the second piston head. The cylinder block can include a first fuel intake port for providing a fuel to the first combustion chamber volume and a second fuel intake port for providing the fuel to the second combustion chamber volume.
[0014] The third piston head can define a second combustion chamber in the cylinder between the third piston head and the first cylinder head, and the first cylinder head can include a third fuel intake port for providing a fuel to the second combustion chamber. The fourth piston head can define a third combustion chamber in the cylinder between the fourth piston head and the second cylinder head, and the second cylinder head can include a fourth fuel intake port for providing a fuel to the third combustion chamber.
[0015] The cylinder block can include a spark device for igniting fuel in the first combustion chamber volume and the second combustion chamber volume. The first cylinder head can include a spark device for igniting fuel in the second combustion chamber. The second cylinder head can include a spark device for igniting fuel in the third combustion chamber.
[0016] The engine can include a first air compression chamber, a first compression plate slidingly arranged in the first air compression chamber and in sealing contact with an inner surface of the first air compression chamber, and a first compression rod connected to the first piston rod and the first compression plate. The first compression plate compresses air in the first air compression chamber upon movement of the first piston rod. The engine can include a first fluid pump chamber, a first pump plate slidingly arranged in the first fluid pump chamber and in sealing contact with an inner surface of the first fluid pump chamber, and a first pump rod connected to the second piston rod and the first pump plate. The first pump plate pumps fluid from the first fluid pump chamber upon movement of the second piston rod. The housing can have a first channel in fluid communication with the first air compression chamber for transporting air from the first air compression chamber, and also a second channel in fluid communication with the first fluid pump chamber for transporting fluid from the first fluid pump chamber.
[0017] The engine can include a drive gear connected to the first power output shaft. The engine can further include a drive element selected from chains and belts, wherein the drive element is coupled to the drive gear.
[0018] In the engine, the first connecting rod can be coupled to a second power output shaft, and a second connecting rod can be coupled to the second power output shaft. The first power output shaft and the second power output shaft can be coaxial. The first connecting rod can be linked to a first set of cams, the second connecting rod can be linked to each of the first set of cams, the second connecting rod can be linked to a second set of cams, and one cam of the second set of cams can be connected to the first power output shaft, and another cam of the second set of cams can be connected to the second power output shaft. The second connecting rod can include a pair of spaced apart arms such that the first connecting rod and the first set of cams can move between the pair of spaced apart arms.
[0019] It is therefore an advantage of the present invention to provide an engine that dramatically reduces cylinder friction and wear thereby improving gas mileage and lowering emissions.
[0020] It is another advantage of the present invention to provide an engine that has increased torque.
[0021] It is still another advantage of the present invention to provide an engine that allows for a low mass piston, which provides for higher speeds and greater horsepower.
[0022] It is yet another advantage of the present invention to provide an engine that can be used for standard internal combustion engines, diesel and 2 cycle designs. It can also be used as a pump if the power is reversed.
[0023] It is still another advantage of the present invention to provide an engine that requires a smaller block and can be mounted sideways.
[0024] It is yet another advantage of the present invention to provide an engine that is suitable for off road vehicles such as ATVs and military equipment.
[0025] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has the upper pistons and lower pistons connected to the same two power output shafts.
[0026] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has the two middle pistons forming a single combustion chamber.
[0027] It is yet another advantage of the present invention to provide an engine, pump, compressor or the like that has one or more of the shafts coming out of the cylinder that connect to a push rod and plates that compress air in the resulting chambers. These chambers compress air in both an up and down motion.
[0028] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has one or more of the shafts coming out of the cylinder that connect to a push rod that pumps oil in a resulting chamber.
[0029] It is yet another advantage of the present invention to provide an engine, pump, compressor or the like that has two power output shafts located between the upper pistons and lower pistons, either directly below the cylinder, or off to the side.
[0030] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has a housing that is extruded, enabled by the design of the pistons and cranks. This housing by design also has channels for water and oil flow either extruded in the housing or molded, cast or added to the inside or outside of the housing.
[0031] It is yet another advantage of the present invention to provide an engine, pump, compressor or the like that has a design that allows for either a two cycle or four cycle engine by adding valves to the piston push rods or chains or belts to the power output shafts. The chains, belts and push rods can be split between both power output shafts or connected just to one power output shaft.
[0032] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has four push rods that are connected directly to a flange designed onto the upper pistons and lower pistons or to a shaft that extends through both sides of the upper pistons and lower pistons.
[0033] It is yet another advantage of the present invention to provide an engine, pump, compressor or the like that has a top plate housing, a bottom plate housing, and a middle housing.
[0034] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has bearings for power output shafts wherein the bearings are housed between two engine housing halves that connect both engine housing halves.
[0035] It is yet another advantage of the present invention to provide an engine, pump, compressor or the like that has four push rods where two of the push rods are Y-shaped or U-shaped to allow for a symmetric distribution of power from the upper pistons and lower pistons.
[0036] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that has valves that are either rocker arm type valves, slide valves or rotary type valves (Coates valves).
[0037] It is yet another advantage of the present invention to provide an engine, pump, compressor or the like that has a fuel injector and a spark plug in the top plate housing, the bottom plate housing, and the middle cylinder block respectively, or aspiration with gas or diesel fuel.
[0038] It is still another advantage of the present invention to provide an engine, pump, compressor or the like that is connected to a second four cylinders that are at 90° or 180° out of phase and connect to the two power output shafts of the first engine half allowing for increased power and a smother running engine.
[0039] These and other features, aspects, and advantages of the present invention will become better understood upon consideration of the following detailed description, drawings, and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] FIG. 1 is a perspective view of a first embodiment of an engine according to the invention.
[0041] FIG. 2 is a front view of the engine of FIG. 1 .
[0042] FIG. 3 is a cross-sectional view taken along line 3 - 3 of FIG. 2 .
[0043] FIG. 4 is a cross-sectional view taken along line 4 - 4 of FIG. 2 .
[0044] FIG. 5 is a cross-sectional view taken along line 5 - 5 of FIG. 3 .
[0045] FIG. 6 is a right front perspective detailed view taken along line 6 - 6 of FIG. 5 showing the linkage between the connecting rods and the power output shafts on one side of the engine of FIGS. 1-6 .
[0046] FIG. 7 is a front view of a second embodiment of an engine according to the invention.
[0047] FIG. 8 is side view of the engine of FIG. 7 .
[0048] FIG. 9 is a cross-sectional view taken along line 9 - 9 of FIG. 8 .
[0049] Like reference numerals are used to depict like parts from Figure to Figure throughout the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0050] The present invention is directed to a piston engine wherein the power take-off is truly balanced and the piston runs truly parallel to the cylinder walls. Looking at FIGS. 1-6 , a first example embodiment of an engine 10 includes a first top outer housing section 12 and a second bottom outer housing section 13 which may be extruded in the hollow generally rectangular shape shown in FIGS. 1-6 . The housing section 12 and the housing section 13 are mated to form an internal cylinder 15 that extends from a top end to a bottom end of the engine 10 . The cylinder 15 defines a cylindrical interior space 16 . It should be understood that the terms “bottom”, “top”, “left” and “right” are used for ease and clarity of description, and in no way do these terms limit the orientation of the engine 10 in operation.
[0051] An open end of the top housing section 12 is closed off by a first end plate 18 that forms a first cylinder head 19 for the cylinder 15 . A combustion chamber 20 is defined below the first cylinder head 19 for the cylinder 15 . A fuel intake port 21 with a fuel injector 22 and a spark plug 23 are arranged in the first cylinder head 19 . Optionally, a carburetor can be associated with the fuel intake port 21 , or the spark plug can be omitted. Each fuel injector or carburetor is positioned for directing fuel and/or intake air in its associated intake port. The operation of internal combustion engines is well known and will not be explained further.
[0052] An open end of the bottom housing section 13 is closed off by a second end plate 25 that forms a second cylinder head 26 for the cylinder 15 . A combustion chamber 27 is defined above the second cylinder head 26 for the cylinder 15 . A fuel intake port 28 with a fuel injector 29 and a spark plug 30 are arranged in the second cylinder head 26 for the cylinder 15 . Optionally, a carburetor can be associated with the fuel intake port 28 , or the spark plug can be omitted. The top housing section 12 , the bottom housing section 13 , the first end plate 18 , and the second end plate 25 can be formed from, for example, an aluminum alloy, a steel alloy, or a composite material.
[0053] The engine 10 includes a first piston 33 slidingly arranged in the interior space 16 of the cylinder 15 . The first piston 33 is in sealing contact with an inner surface of the cylinder 15 . The first piston 33 reciprocates in the interior space 16 of the cylinder 15 . The first piston 33 includes a first piston head 34 . At the end of the first piston 33 opposite the first piston head 34 , one or more flanges of the first piston 33 are connected to a first piston rod 36 which extends diametrically across the end of the first piston 33 .
[0054] The engine 10 includes a second piston 39 slidingly arranged in the interior space 16 of the cylinder 15 . The second piston 39 is in sealing contact with an inner surface of the cylinder 15 . The second piston 39 reciprocates in the interior space 16 of the cylinder 15 . The second piston 39 includes a second piston head 40 . At the end of the second piston 39 opposite the second piston head 40 , one or more flanges of the second piston 39 are connected to a second piston rod 42 which extends diametrically across the end of the second piston 39 .
[0055] The engine 10 includes a third piston 44 slidingly arranged in the interior space 16 of the cylinder 15 . The third piston 44 is in sealing contact with an inner surface of the cylinder 15 . The third piston 44 reciprocates in the interior space 16 of the cylinder 15 . The third piston 44 includes a third piston head 45 . At the end of the third piston 44 opposite the third piston head 45 , one or more flanges of the third piston 44 are connected to the first piston rod 36 which extends diametrically across the end of the third piston 44 .
[0056] The engine 10 includes a fourth piston 47 slidingly arranged in the interior space 16 of the cylinder 15 . The fourth piston 47 is in sealing contact with an inner surface of the cylinder 15 . The fourth piston 47 reciprocates in the interior space 16 of the cylinder 15 . The fourth piston 47 includes a fourth piston head 48 . At the end of the fourth piston 47 opposite the fourth piston head 48 , one or more flanges of the fourth piston 47 are connected to the second piston rod 42 which extends diametrically across the end of the fourth piston 47 .
[0057] Each of the pistons 33 , 39 , 44 , 47 can have a pair of O-rings on its outer surface. A first of the pair of O-rings for each of the pistons 33 , 39 , 44 , 47 is an oil wiping ring located at the end of each of the pistons 33 , 39 , 44 , 47 that connects to the adjacent piston. This O-ring seals oil from the inside of the associated combustion chamber. A second of the pair of O-rings for each of the pistons 33 , 39 , 44 , 47 is located about ⅔ to ¾ of the way to the end of each of the pistons 33 , 39 , 44 , 47 near the associated combustion chamber. This O-ring seals off the combustion chamber.
[0058] The engine 10 includes a cylinder block 50 that defines a first combustion chamber volume 51 between the cylinder block 50 and the first piston head 34 , and that defines a second combustion chamber volume 52 between the cylinder block 50 and the second piston head 40 . A first fuel intake port 53 , a second fuel intake port 54 , a fuel injector 55 , and a spark plug 56 are provided in the cylinder block 50 . The first fuel intake port 53 can provide fuel from the fuel injector 55 to the first combustion chamber volume 51 . The second fuel intake port 54 can provide fuel from the fuel injector 55 to the second combustion chamber volume 52 . The spark plug 56 can ignite fuel in the first combustion chamber volume 51 and the second combustion chamber volume 52 .
[0059] The engine 10 includes a first connecting rod 58 that is attached by a pin to the first piston rod 36 , a second connecting rod 59 that is attached by a pin to the second piston rod 42 , a third connecting rod 60 that is attached by a pin to the first piston rod 36 . and a fourth connecting rod 61 that is attached by a pin to the second piston rod 42 . Referring to FIGS. 4 and 6 , the first connecting rod 58 is connected to a first set of cams 64 a , 64 b and the second connecting rod 59 is connected by spaced apart arms 63 to a second set of cams 65 a , 65 b . Cam 65 a is connected to a first power output shaft 67 , and cam 65 b is connected to a second power output shaft 68 . A third power output shaft 69 and a fourth power output shaft (not shown) are connected to the third connecting rod 60 and the fourth connecting rod 61 in the same manner as the connections between the first connecting rod 58 , the second connecting rod 59 , the first power output shaft 67 , and the second power output shaft 68 . A bearing plate 70 a connects both the top housing section 12 and the bottom housing section 13 , and also acts as bearing surface for the first output shaft 67 . Likewise, a bearing plate 70 b connects both the top housing section 12 and the bottom housing section 13 , and also acts as bearing surface for the second power output shaft 68 . Similar bearing plates are provided for the third power output shaft 69 and the fourth power output shaft.
[0060] A first drive gear 71 is connected to the first power output shaft 67 , and a second drive gear 72 is connected to the third power output shaft 69 as shown in FIG. 1 . A chain 73 can transmit motion from the first drive gear 71 (see FIG. 2 ). Similar drive gears and chains can be provided on the second power output shaft 68 and the fourth power output shaft.
[0061] The engine 10 includes a first air compression chamber 75 adjacent the first end plate 18 . A first compression plate 77 is slidingly arranged in the first air compression chamber 75 , and the first compression plate 77 is in sealing contact with an inner surface of the first air compression chamber 75 . A first compression rod 78 is connected to the first compression plate 77 . The first compression rod 78 is also connected to the first piston rod 36 by a pin 79 . The first compression plate 77 compresses air in the first air compression chamber 75 . The air is compressed in both an up and down motion. A channel 80 is in fluid communication with the first air compression chamber 75 for transporting air from the first air compression chamber 75 . The channel can be extruded in the top housing section 12 and/or the bottom housing section 13 , or molded, cast or added to the top housing section 12 and/or the bottom housing section 13 .
[0062] The engine 10 includes a second air compression chamber 81 adjacent the first end plate 18 . A second compression plate 82 is slidingly arranged in the second air compression chamber 81 , and the second compression plate 82 is in sealing contact with an inner surface of the second air compression chamber 81 . A second compression rod 83 is connected to the second compression plate 82 . The second compression rod 83 is also connected to the first piston rod 36 by a pin 84 . The second compression plate 82 compresses air in the second air compression chamber 81 . The air is compressed in both an up and down motion. A channel is in fluid communication with the second air compression chamber 81 for transporting air from the second air compression chamber 81 . The channel can be extruded in the top housing section 12 and/or the bottom housing section 13 , or molded, cast or added to the top housing section 12 and/or the bottom housing section 13 .
[0063] The engine 10 includes a first fluid pump chamber 86 adjacent the second end plate 25 . A first pump plate 87 is slidingly arranged in the first fluid pump chamber 86 , and the first pump plate 87 is in sealing contact with an inner surface of the first fluid pump chamber 86 . A first pump rod 88 is connected to the first pump plate 87 . The first pump rod 88 is also connected to the second piston rod 42 by a pin 89 . The first pump plate 87 pumps fluid from the first fluid pump chamber 86 upon movement of the second piston rod 42 . A channel is in fluid communication with the first fluid pump chamber 86 for transporting air from the first fluid pump chamber 86 . The channel can be extruded in the top housing section 12 and/or the bottom housing section 13 , or molded, cast or added to the top housing section 12 and/or the bottom housing section 13 .
[0064] The engine 10 includes a second fluid pump chamber 91 adjacent the second end plate 25 . A second pump plate 93 is slidingly arranged in the second fluid pump chamber 91 , and the second pump plate 93 is in sealing contact with an inner surface of the second fluid pump chamber 91 . A second pump rod 94 is connected to the second pump plate 93 . The second pump rod 94 is also connected to the second piston rod 42 by a pin 95 . The second pump plate 93 pumps fluid from the second fluid pump chamber 91 upon movement of the second piston rod 42 . A channel 96 is in fluid communication with the second fluid pump chamber 91 for transporting air from the second fluid pump chamber 91 . The channel can be extruded in the top housing section 12 and/or the bottom housing section 13 , or molded, cast or added to the top housing section 12 and/or the bottom housing section 13 .
[0065] In FIG. 5 , the first piston 33 and the third piston 44 (which are connected to the first piston rod 36 ) are shown near bottom of their stroke, and the second piston 39 and the fourth piston 47 (which are connected to the second piston rod 42 ) are shown near top of their stroke. At the time in the engine cycle shown in FIG. 5 , the spark plug 56 will fire, fuel and air in the first combustion chamber volume 51 and the second combustion chamber volume 52 has been compressed, and when the spark plug 56 fires, the fuel-air mixtures ignite. The resulting explosions drive the second piston 39 and the fourth piston 47 downward and the first piston 33 and the third piston 44 upward.
[0066] When the first piston 33 and the third piston 44 are near top of their motion, and the second piston 39 and the fourth piston 47 are near bottom of their motion, the spark plugs 23 , 30 will fire, fuel and air in the combustion chambers 20 , 27 has been compressed, and when the spark plugs 23 , 30 fire, the fuel-air mixtures ignite. The resulting explosion drives the first piston 33 and the third piston 44 downward and the second piston 39 and the fourth piston 47 upward.
[0067] As the first piston 33 and the third piston 44 reciprocate, the first piston rod 36 rotates the first set of cams 64 a , 64 b, the first piston rod 36 translates the first compression rod 78 such that the first compression plate 77 compresses air in the first air compression chamber 75 , and the first piston rod 36 translates the second compression rod 83 such that the second compression plate 82 compresses air in the second air compression chamber 81 . As the first piston 33 and the third piston 44 reciprocate, the first piston rod 36 rotates a set of cams (similar to the first set of cams 64 a , 64 b ) on the opposite side of the cylinder. Rotation of the first set of cams 64 a , 64 b provides rotation to the first power output shaft 67 and second power output shaft 68 , and rotation of the similar set of cams on the opposite side of the cylinder 15 provides rotation to the third power output shaft 69 and the fourth power output shaft.
[0068] As the second piston 39 and the fourth piston 47 reciprocate, the second piston rod 42 rotates the second set of cams 65 a , 65 b (and the similar set of cams on the opposite side of the cylinder 15 ), the second piston rod 42 translates the first pump rod 88 such that the first pump plate 87 pumps fluid from the first fluid pump chamber 86 , and the second piston rod 42 translates the second pump rod 94 such that the second pump plate 93 pumps fluid from the second fluid pump chamber 91 . Rotation of the second set of cams 65 a , 65 b provides rotation to the first power output shaft 67 and second power output shaft 68 . Rotation of a set of cams (similar to the second set of cams 65 a , 65 b ) provides rotation to the third power output shaft 69 and fourth power output shaft.
[0069] Looking at FIGS. 7-9 , a second example embodiment of an engine 110 is shown. The engine 110 includes a first outer housing section 112 and a second outer housing section 113 which may be extruded in the hollow generally rectangular shape shown in FIGS. 7-9 . The housing section 112 and the housing section 113 can be formed from, for example, an aluminum alloy, a steel alloy, or a composite material. The housing section 112 and the housing section 113 are mated to form an internal cylinder 115 that extends from a top end to a bottom end of the engine 110 . The cylinder 115 defines a cylindrical combustion chamber 116 . An open end of the housing sections 112 , 113 is closed off by a first end plate 118 . An opposite open end of the housing sections 112 , 113 is closed off by a second end plate 125 . It should be understood that the terms “bottom”, “top”, “left” and “right” are used for ease and clarity of description, and in no way do these terms limit the orientation of the engine 110 in operation.
[0070] The engine 110 includes a first piston 133 slidingly arranged in the combustion chamber 116 of the cylinder 115 . The first piston 133 is in sealing contact with an inner surface of the cylinder 115 . The first piston 133 reciprocates in the combustion chamber 116 of the cylinder 115 . The first piston 133 includes a first piston head 134 . At the end of the first piston 133 opposite the first piston head 134 , one or more flanges of the first piston 133 are connected to a first piston rod 136 which extends diametrically across the end of the first piston 133 .
[0071] The engine 110 includes a second piston 139 slidingly arranged in the combustion chamber 116 of the cylinder 115 . The second piston 139 is in sealing contact with an inner surface of the cylinder 115 . The second piston 139 reciprocates in the combustion chamber 116 of the cylinder 115 . The second piston 139 includes a second piston head 140 . At the end of the second piston 139 opposite the second piston head 140 , one or more flanges of the second piston 139 are connected to a second piston rod 142 which extends diametrically across the end of the second piston 139 .
[0072] Each of the pistons 133 , 139 can have one or more O-rings on its outer surface. Oil ring slots and associated O-rings 149 a , 149 b are provided in the cylinder to seal oil from the inside of the combustion chamber 116 .
[0073] Fuel intake ports 153 , 154 and a spark plug 156 are provided in the cylinder 115 . The fuel intake ports 153 , 154 can provide fuel to the combustion chamber 116 . The spark plug 156 can ignite fuel in the combustion chamber 116 . The engine 110 further includes a first exhaust pipe 146 in fluid communication with an exhaust port 147 in the cylinder 115 , and a second exhaust pipe 148 in fluid communication with another exhaust port (not shown) in the cylinder 115 . The fuel intake ports 153 , 154 and exhaust ports 147 are at opposite ends of the cylinder 115 .
[0074] The engine 110 includes a first connecting rod 158 that is attached by a pin to the first piston rod 136 , a second connecting rod 159 that is attached by a pin to the second piston rod 142 , a third connecting rod 160 that is attached by a pin to the first piston rod 136 . and a fourth connecting rod 161 that is attached by a pin to the second piston rod 142 . Referring to FIG. 9 , the first connecting rod 158 and the second connecting rod 159 are connected to a first set of cams 164 . The third connecting rod 160 and the fourth connecting rod 161 are connected to a second set of cams 165 . Cams 164 are connected to a first power output shaft 167 and a second power output shaft 168 . Cams 165 are connected to third power output shaft 169 and a fourth power output shaft (not shown).
[0075] The first connecting rod 158 , the second connecting rod 159 and the first set of cams 164 of the engine 110 can be constructed and assembled in the manner shown in FIG. 6 for engine 10 . Likewise, the third connecting rod 160 , the fourth connecting rod 161 , and the second set of cams 165 of the engine 110 can be constructed and assembled in the manner shown in FIG. 6 for engine 10 .
[0076] A first drive gear 171 is connected to the first power output shaft 167 , a second drive gear 172 is connected to the second power output shaft 168 , and a third drive gear 173 is connected to the third power output shaft 169 as shown in FIGS. 7-8 . A chain can transmit motion from any of the drive gears as in the embodiment of FIG. 2 . A similar drive gear and chain can be provided on the fourth power output shaft.
[0077] In FIG. 9 , the first piston 133 , which is connected to the first piston rod 136 , is shown near the top of its stroke, and the second piston 139 , which is connected to the second piston rod 142 , is shown near the bottom of its stroke. When the first piston 133 is near bottom of its motion, and the second piston 139 is near top of its motion, the spark plug will fire, fuel and air in the combustion chamber 116 has been compressed, and when the spark plug fires, the fuel-air mixture ignites. The resulting explosion drives the first piston 133 upward and the second piston 139 downward back to the positions shown in FIG. 9 .
[0078] As the first piston 133 reciprocates, the first piston rod 136 rotates the first set of cams 164 and the second set of cams 165 . As the second piston 139 reciprocates, the second piston rod 142 also rotates the first set of cams 164 and the second set of cams 165 . Rotation of the first set of cams 164 provides rotation to the first power output shaft 167 and second power output shaft 168 . Rotation of the second set of cams 165 provides rotation to the third power output shaft 169 and fourth power output shaft.
[0079] Thus, the invention provides an engine where power take-off is truly balanced such that the piston runs truly parallel to the cylinder walls, that provides improved gas mileage by reducing piston drag, and that produces greater torque.
[0080] Although the present invention has been described in considerable detail with reference to certain embodiments, one skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which have been presented for purposes of illustration and not of limitation. Therefore, the scope of the appended claims should not be limited to the description of the embodiments contained herein. | An engine having axial inline pistons connected to side power output shafts is disclosed. The engine includes a cylinder defining an interior space of the cylinder; a first piston that reciprocates in the interior space of the cylinder wherein the first piston has a first end forming a first piston head; a first piston rod attached to the first piston at a second end of the first piston opposite the first end of the first piston; a second piston that reciprocates in the interior space of the cylinder, wherein the second piston has a first end forming a second piston head; a second piston rod attached to the second piston at a second end of the second piston opposite the first end of the second piston; a first connecting rod connected to the first piston rod and coupled to a first power output shaft; and a second connecting rod connected to the second piston rod and coupled to the first power output shaft. The first piston head and the second piston head define a combustion chamber in the cylinder between the first piston head and the second piston head, and the first piston head and the second piston head move away from each other on a first power stroke of the first piston and a second power stroke of the second piston. | 5 |
BACKGROUND OF THE INVENTION
This invention relates the regulation of the fiber quantities introduced into a fiber tuft feeding apparatus and concerns, in particular to a pressure-responsive electronic switch that includes an axially adjustable electronic proximity switch, a diaphragm spaced from the proximity switch and positioned in an orientation perpendicular to the axis thereof and a metal plate supporting the diaphragm in a face-to-face relationship therewith. There is further provided a compression spring arranged coaxially about the proximity switch and biasing the metal plate.
In a known electronic pressure-responsive switch of the above-outlined type the compression spring yields as the external pressure which is to be sensed and to which the diaphragm is exposed, increases so that upon reaching a predetermined setting pressure, the metal plate arrives in the switching zone of the electronic proximity switch. Upon this occurrence, a thyristor contained in the proximity switch fires and thus causes a voltage to appear at the output of the pressure-responsive switch. If the external pressure to be sensed drops below a set switching pressure, the thyristor blocks, resulting in a disappearance of the voltage from the output of the pressure-responsive switch.
An electronic pressure-responsive switch of the above-outlined type may constitute a measuring member of a regulating circuit for a fiber tuft feeding apparatus serving a carding machine. Such a regulating circuit comprises a regulator and further, a tuft feeding roll of the feeding apparatus constitutes, a setting member. Such a system, including the above-outlined pressure-responsive switch, is disclosed in U.S. Pat. No. 4,161,052, issued July 17th, 1979.
With a pressure-responsive switch disclosed in the above patent, only a two-point regulation can be obtained. Thus, upon exceeding or falling below a predetermined pressure, the feeding roll is deenergized or energized. Since the conventional electronic proximity switch emits a digital electric signal, the feeding roll cannot be regulated continuously and in a stepless manner.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved fiber tuft feeding apparatus, whose fiber quantity measuring member particularly an electronic pressure-responsive switch provides, in a regulating circuit, for a continuous and stepless regulation of the setting member.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, to the setting member analog setting signals are applied as a function of signals emitted by a fiber tuft quantity sensor, particularly an electronic proximity switch responding to tuft quantity-dependent pressure fluctuations.
With the arrangement according to the invention, it is possible to continuously and steplessly regulate the setting member in a regulating circuit.
In a preferred application of the invention, the electronic pressure-responsive switch is used as the measuring member at a feeding shaft of a tuft feeding apparatus for a carding machine for regulating the tuft quantities introduced into the feeding shaft. According to another preferred application of the invention, the electronic pressure-responsive switch constitutes the measuring member arranged at a feeding and distributor conduit of a pneumatic tuft feeding apparatus for regulating the throughput of tuft quantities in the conduit. In this manner it is feasible to regulate the admission of the tufts in the feeding shaft in a stepless manner and as a function of the pressure in the feeding shaft. The tuft stream can thus be continuously and steplessly changed, resulting in a high degree of uniformity of the tuft quantities discharged by the feeding shaft throughout long operational periods.
BRIEF DESCRIPTI0N OF THE DRAWINGS
FIG. 1 is a schematic side elevational view of a carding machine and a tuft feeding apparatus, incorporating the invention.
FIG. 2 is an axial sectional view of a preferred embodiment of the electronic pressure-responsive switch according to the invention.
FIG. 3a is a schematic side elevational view of a tuft feeding installation incorporating the invention.
FIG. 3b is a top plan view of the structure shown in FIG. 3a.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIG. 1, textile fiber tufts are introduced from a fine opening arrangement (not shown) through a feeding and distributor conduit (also not shown) into an upper tuft shaft 1 (material storage shaft). Then a feeding roll 2 and an opening roll 3 forward the tufts to a lower tuft shaft (feeding shaft) 4. The feeding shaft 4 supplies the textile fiber tufts as a fiber web to a carding machine 5. The textile fiber web discharged by the carding machine is gathered into a sliver by means of a sliver trumpet 6.
To a wall of the feeding shaft 4, there is attached an electronic pressure-responsive switch 8 constituting a measuring member. The pressure-responsive switch 8 is connected to a regulator 9 which, in turn, is connected to the drive 2a of the feeding roll 2. During operation, the electronic pressure-responsive switch 8 senses the pressure prevailing in the feeding shaft 4. The electronic pressure-responsive switch converts this pressure--in a manner to be described below--into an analog signal x which is applied to the regulator 9. The latter, in response, generates a setting signal y which is applied to the drive 2a of the feeding roll 2. By varying the rpm of the feeding roll 2 as a function of the pressure fluctuations in the feeding shaft 4, there is effected a continuous alteration of the tuft quantities in the feeding shaft 4.
The electronic pressure-responsive switch 8, which in principle, is provided to convert pressure fluctuations into electrical signals, may include, for example, known piezoelectric crystal elements. This conversion may also be effected by means of known elements, such as a slide resistor, resistance strain gauge, capacitor or light barrier. As seen in FIG. 2, signals x leave the electronic proximity switch 14 which is part of the pressure-sensitive switch 8, rather than the regulator 9. Thus the signals x cannot be applied directly to the drive of the feeding roll 2; they must be fed into the regulator 9 (switchboard with switching relays or equivalent electrical or electronic elements) where they are processed into a further pulse train y which acts on the motor of the feeding roll 2. The pressure-responsive switch 8 will now be described in more detail with reference to FIG. 2.
In a wall portion of the feeding shaft 4, there is provided an opening 10 which is closed by a diaphragm 11 of the electronic pressure-responsive switch 8. The diaphragm 11 which may be an elastomer, is clamped into a switch housing 8a and is, on its face oriented away from the feeding shaft 4, supported by a metal plate 12.
The housing 8a further accommodates an analog signal-emitting electronic proximity switch 14 which may be the commercially available model IA-4010-D "efector" manufactured by IFM Electronic of Essen, Federal Republic of Germany. The electronic proximity switch 14 is, along a part of its length, surrounded by a coil spring 13, whose one end engages a bottom part of the housing 8a, while its other end engages the metal support plate 12. A clearance 15 is provided between an end 14a of the electronic proximity switch 14 and the metal plate 12. The clearance 15 is adjustable by changing the axial position of the proximity switch 14 by virtue of its threaded connection with the housing 8a. The other, opposite end of the electronic proximity switch 14 is connected with the regulator 9 (FIG. 1) by means of a conductor 16.
The electronic pressure-responsive switch 8 is adapted to measure the pressure prevailing in the feeding shaft 4 in a range from 0 to 150 mm WS. Pressure fluctuations in this range are converted by the electronic proximity switch 14 into the continuous analog signal x as a function of the pressure-dependent distance of the metal plate 12 from the end 14a of the electronic proximity switch 14. In the range between 50 and 150 mm WS, the output signal x of the electronic proximity switch 14 is linearly proportionate to the pressure in the feeding shaft 4.
FIG. 3a is an elevational view and FIG. 3b is a plan view of a tuft feeding installation. A transport blower 17 has its suction side connected to a fine opener 18. The suction pipe of the transport blower 17 is connected to a feeding and distributing conduit 19 which extends above card feeders 20 and to which are connected the reserve shafts 1. Above the first reserve shaft 1, the electronic pressure-responsive switch 8 is attached to the distributing conduit 19.
The transport blower 17 sucks the opened fiber material from the last beater position of the opening system--e.g. the fine opener 18--and conveys it in a stream of transporting air through the feeding and distributing conduit 19 to the reserve shafts 1 of the connected card feeders 20.
When the mixture of tufts and air enters the reserve shafts 1, the air escapes through the transporting air discharge filters (not shown) and the tufts are deposited in the reserve shafts 1 where the columns of material develop.
This increase in pressure continues with increasing fill level of the reserve shafts 1.
To the beginning of the distributing conduit 19, above the first reserve shaft 1, there is connected a fine pressure gauge 21 to indicate the pressure in mm column of water and the electronic pressure-responsive switch 8 to control the supply of material from the fine opener 18 to the transport blower 17.
In this way, more or less fiber material reaches the transport blower 17. The transport blower 17 continues to operate and conveys fiber material and air into the feeding and distributing conduit 19 and maintains the pressure conditions.
The electronic pressure-responsive switch 8 is connected with an electric drive motor 22 with the intermediary of a regulator 9 which may include a time relay. By means of an infinitely variable gear system (not shown), the drive motor 22 drives an opening roll (not shown), e.g. Kirschner wings, in the fine opener 18. In the described embodiments, the electronic pressure-responsive switch 8 acts on the feeding roll 2 or the fine opener 18, respectively. It may also affect, however, further setting members with which the quantity of tufts to be transported is varied.
The electronic pressure-responsive switch 8 may be used with every tuft feeding system (chute feeding system) for textile machines. It can also be used with a "pneumafeeder", that is, a box feeder for beater machines.
It is to 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. | In a fiber tuft feeding apparatus the throughgoing tuft quantities are sensed, signals representing such quantities are emitted and in response to the signals, a tuft quantity metering member, such as a feeding roll is controlled by analog setting signals. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to a system of sealing wedge-type gun breech mechanisms.
A former proposal of the claimant (P No. 24 35 520) related to a wedge-type breech mechanism using a sealing ring which is pre-loaded by a gear system, designed for weapons firing caseless ammunition. Both, the sealing ring and the gear system are comprised in a recess provided in the wedge. The sealing ring axially slides into contact with the plane surface of the barrel; this feature is provided by a clamping stud supported by the wedge and an intermediate ring engaged with the clamping stud by a worm. Both, the clamping stud and the intermediate ring are provided with vent holes.
Prior to opening the wedge, load is relieved from the sealing ring by sliding back the intermediate ring. Thus, the sealing ring returns from the plane surface of the barrel, when the wedge extends. This proposal ensures a gasproof sealing of the breech with weapons generating gas pressures up to 4,500 bars. With extremely high gas pressures involved -- up to 8,000 bars -- however, the strength of the lateral walls of the wedge comprising the sealing system is affected to such extent that service life can no longer be guaranteed. The reason is that the wedge is provided with a relatively deep longitudinal recess which is necessary to house the sealing ring and the gear system, thus reducing the bending strength of the lateral walls of the wedge which could be broken.
SUMMARY OF THE INVENTION
An object of this invention is to provide a space-saving sealing system for extremely high gas pressures. The advantage is that the gas pressure of a caseless ammunition acting on the base will intensify the mechanically generated specific surface pressure of the sealing ring against the plane surface of the barrel whereby the degree of intensification depends on the gas pressure. Another advantage is the relatively flat design of this sealing system consisting of very few parts, ensuring that the strength limit of the lateral walls of the wedge is not exceeded. Furthermore, a sealing system of such type can be integrated in a wedge without any modification of the breech contours.
There is also recited a rapidly responding, pressure-actuated supporting of the ring respectively the intermediate ring; a space-saving drive coupling between clamping stud and sealing ring; particularly flat and reliable shift segments; and the latter with different drive systems.
BRIEF DESCRIPTION OF THE DRAWINGS
Practical examples of this invention are illustrated by a drawing which shows in particular:
FIG. 1 is a cross section of a sealing system integrated in a wedge type breech mechanism of a firearm
FIG. 1a is a detail from FIG. 1;
FIG. 2 is an end view of the device according to FIG. 1;
FIG. 3 is a cross section taken along line III--III in FIG. 4 of another embodiment of sealing system;
FIG. 4 is an end view of the device according to FIG. 3;
FIG. 5 is a detail from another embodiment of sealing system;
FIG. 6 shows, partially in section, a shift segment according to FIG. 5;
FIG. 7 is a side view of shift segment according to the embodiments of FIGS. 1 and 3.
DETAILED DESCRIPTION
In the breech end 1 of a cannon having a barrel 2 of 150 mm caliber with a wear-resistant ring 3, a wedge 4 in locked position and a lever 6 on a shaft 5 are provided. The conventionally activated lever 6 which uses a notch 7, eccentric cam plate 8 and cams 9 is thrown into engagement with guide cams 11 of the wedge 4 via two rollers 10. Beginning with the release position A, the guide cams 11 have a section 12 which is concentric with the axis of rotation of lever 6.
Recess 13 in the wedge 4 houses -- on a plate 15 attached to wedge 4 with countersunk screws 14 -- a lever transmission 16 consisting of a roller-guided lever 17 and a clamping lever 18 through bolts 19, 20 in wedge 4.
With roller-guided lever 17, eccentric cam plate 8 with its roller 21 and, furthermore, two return cam plates 22, one safety return cam plate 23 and a connecting link bolt 24 are provided. The clamping lever 18 has a connecting link 25, a toothed segment 27 which is in mesh with clamping stud 26, and a cam 28. An axially displaceable sliding segment 29, actuated by cam 28 and lever 30 in wedge 4 is provided in the clamping stud 26. Furthermore, the clamping stud 26 encloses an electric ignition unit 31 with firing pins 32 and 33 mounted on the sliding segment 29.
The firing pin 32 is directly connected to the sliding segment 29 thus being electrically grounded. The firing pin 33 is insulated from the sliding segment 29, clamping stud 26, and guiding plate 34, but is rigidly connected to the sliding segment 29 by an insulating insert 39. Furthermore, the firing pin 33 is connected to a common ignition system -- which is not shown here -- via a sliding contact 35 and a cable 36. The firing pins 32 and 33 extend into the barrel 2 and are provided with gaskets 37.
The axis of rotation B of the clamping lever 18 is displaceable against the wedge 4. For this purpose a setting device 38 is provided in wedge 4, consisting of a rotatable bolt 20 with thread 41, bolt flange 42 and hexagonal recessed hole 44 and a bridge 45 screwed to wedge 4 and provided with a bearing seat 46.
The clamping stud 26 which is axially displaceable in hole 47 provided in wedge 4, has tooth gaps 48 corresponding with toothed segment 27 and -- in the clamped configuration -- abuts on the base 51 of a recess 52 in wedge 4 with its flange 50 and simultaneously abuts with its tapered section 52 on a shift segment which is designed as a ball bearing 54 with cage 49 (FIG. 7).
A tapered section 53 is engaged by means of a flange 55 which is connected to the clamping stud 26 by notches 56. Between notches 56 vent holes 57 are provided. A pressure plate 58 covers the base of recess 52. In the preloaded configuration of sealing ring 60 (see FIGS. 1 and 1a) the notches 56 and pressure plate 58 have a clearance 59.
A sealing ring 60 axially slidable in recess 52 has a flat trapezoidal cross section and an inside taper 61, which together with the outside taper 53 and pressure plate 58 encloses balls 62 of ball bearing 54. This sealing ring 60 is assembled against ring 3 in a manner which will eliminate any section of attack for the gas pressure acting in direction X.
With the chamber 63 open, the wedge recess, not shown in the drawing, is below the chamber 63 in position C. After feeding-in ammunition through recess 66 in the breech end 1 and proceeding to the chamber 63, wedge 4 is moved into the illustrated locked position by the hydraulically actuated arbor 5, lever 6 and rollers 10 running in the guide cams 11.
In position A of lever 6, wedge 4 remains at rest due to the concentric section 12 whereas lever 6 proceeds to clamped position E.
Beginning with position A, the eccentric cam 8 pushes up the roller lever 17 by actuating roller 21. Using the connecting link assembly 24 and 25, the clamping lever 18 moves the clamping stud 26 in direction X until its flange 50 contacts the base 51 of recess 52.
In the direction opposite to X, the firing pins 32 and 33 are actuated and come into contact with the ammunition primer, by actuating lever 30 and sliding segment 29.
An essential factor for the axial preloading of the sealing ring 60 at ring 3 is that before having reached position D, i.e. before flange 50 contacts base 51, the sealing ring 60 performs a short stroke until it contacts ring 3.
The preloading of the sealing ring 60 at ring 3 depends on the clearance 67 of position D from base 51. The flange 50 being in contact with base 51, the preloaded sealing ring 60 is in contact with ring 3, whereby the elastic notches 56 together with clearance 59 are used to limit the preload force. By suitable washers (not shown) lying on base 50, this preload force can be varied.
Contact of flange 50 with base 51 is obtained by once adjusting the setting device 38.
The gas pressure of caseless ammunition acting in direction X generates a certain energy through notches 56 and flange 55 which is reversed by the balls 62 and sealing ring 60, thus provoking an almost immediate increase of the specific surface pressure on the plane sealing surface of sealing ring 60. Simultaneously, the gas pressure expands sealing ring 60 against the wall of recess 52 so that gas penetration through the gap is impossible.
After having fired the round, lever 6 is pivoted in counterclockwise direction until the wedge syncline reaches position C. During the motion of lever 6 from position E to position A roller 21 is relieved from the eccentric cam 8. Thus the preload of sealing ring 60 is eliminated. Cam 9 slides up roller lever 17 via return guide cams 22. Thus clamping stud 26 performs a relief stroke in opposite direction of X from position F to G, via clamping lever 18, so that the external taper 53 is lifted from balls 62; sealing ring 60, ball bearing 49, and flange 55 are completely free from load and lie respectively in recess 52. This configuration is completed when lever 6 has reached position A.
During extending and retracting wedge 4, notch 7 faces the safety return cam plate 23 in order to define the position of clamping stud 26.
Instead of the displaceable clamping stud actuated by lever transmission 16, a rotating clamping stud 71 actuated by lever transmission 70 is used in FIGS. 3 and 4. For this purpose roller lever 17 is connected with a toothed segment 72 and a twin lever 74 rotating around a bolt 73 secured to wedge 4.
A setting device is provided between lever 74 and roller lever 17, consisting of two elastically hinged threaded pins 76 and 77, a threaded bushing 78 and a securing nut 79. Thus the preload between sealing ring 60 and ring 3 is adjustable.
A rough setting feature for the preload is given by a gearwheel with outside and inside toothing 80 which is displaceable against the toothing 82 of clamping stud 11 after having lifted the cover. Screws 83 are used to lock the cover. A supporting disk 84 is enclosed between gearwheel 80 and base 85 of recess 13.
Attached to flange 50, clamping stud 71 has a trapezoidal thread 86 in mesh with an intermediate ring 87. With sealing ring 60 being preloaded, clearance 59 is produced, as already shown in FIG. 1.
The intermediate ring 87 is secured against rotation by a pin 89 secured to the wedge end engaged in hole 88 of intermediate ring 87. As already shown in FIG. 1, intermediate ring 87 has an external taper 53 and vent holes 57.
Closing and opening the wedge 4 as well as pivoting roller lever 17 is performed in a manner described in FIG. 1. Deviating from this, the pivot motion of roller lever 17 is converted to a translative motion via threaded pins 76 and 77 and to a rotation of clamping lever 71 via lever 74.
Clamping lever 71 turns clockwise for the sealing of wedge 4, to slide intermediate ring 87 in direction X, which itself is prevented from rotating by pin 89. In consequence, balls 62 are preloaded radially and sealing ring 60 is preloaded against ring 3. The gas pressure of a caseless propellant charge acts againt intermediate ring 87 which moves in direction X due to its elasticity and its very low thread play. Sealing ring 60 is subjected to an additional press load. The specific surface pressure at ring 3 is raised. Furthermore, the specific surface pressure of flange 50 against base 51 is raised so that pressure loss is impossible as well.
The sealing ring 60 is relieved in a manner similar to FIG. 1, namely, lever 6 is pivoted counter-clockwise, provoking a counter-clockwise rotation of clamping stud 71. Thus the intermediate ring 87 is lifted from the balls, which will relieve the sealing ring 60. Instead of ball bearing 54 as shown in FIGS. 1, 3, and 7, a prismatic ring 90 with two prismatic surfaces 91 and 92 is provided according to FIGS. 5 and 6. Its surface 93 facing the pressure plate has a recess to apply a lubricant 94. By means of a slot 95 this prismatic ring moves radially, i.e. for clamping the sealing ring it will expand, and it will contract for relief.
The intermediate ring 96 shown by FIG. 5 which is block-shaped and nonelastic -- in contrary to FIG. 3 -- uses a higher thread play 97 than the intermediate ring according to FIG. 3 in its clamped configuration. This thread play allows it to return due to the gas pressure, thus increasing the specific surface pressure against the plane surface of sealing ring 60.
Vent holes 57 in flange 55 according to FIG. 1 as well as in the intermediate rings 87 and 96 according to FIGS. 3 and 5 are designed in a manner which will allow the gas pressure to act against the flange and intermediate ring during projectile travel in the barrel, thus improving the sealing feature of sealing ring 60. | A system for sealing a wedge-type breech mechanism for a weapon firing caseless ammunition using a clamping stud in the external drive and enclosed in a recess provided in a wedge which axially presses a sealing ring against the sealing surface of a chamber wherein gear actuated clamping studs press a sealing ring against its sealing surface by a radially displaceable segment. | 5 |
FIELD OF INVENTION
This invention relates to motorized swimming and diving devices, specifically to an improved propulsion device for persons engaged in swimming, snorkeling, skin diving and scuba diving.
DESCRIPTION OF PRIOR ART
Although prior art has taught a variety of motorized swim and scuba diving aids, none of the prior art has suggested attachment of these devices to the user's forearms.
SUMMARY
My invention consists of arranging the control switch, battery, motor, and propeller with shroud in a linear manner, the first three of these being in a watertight housing designed to be strapped to the user's forearm.
Accordingly several objects and advantages of my invention are compactness, lightweightness, mutually independent operations ease of maneuverability, and fingertip controlability.
The compactness and low weight of units makes them ideal for secure attachment to a swimmers or scuba divers forearms. The strapping means allows units to be securely strapped to users forearms thereby eliminating the chance of losing units or losing control of said units. Compared with larger and heavier units currently on the market, general mobility is greatly increased during entry or exit of pool, beach, lake or ocean environments. Furthermore, directional control and maneuverability is quick and easy to learn. Being towed by the propulsion devices securely strapped to users arms is not tiresome to the hands or arms of user and thereby also provides a high degree of steering ease and ability when navigating through water. Furthermore, fingers and hands are left generally free to manipulate other objects as needed such as masks, snorkels, regulators, spear guns, nets, tools or camera equipment.
Still further objects and advantages are to provide propulsion units that are compact and completely self contained in regard to motor, energy source, fingertip speed control switches and optional lighting means for night time or deep diving. Further objects and advantages of the invention will become apparent from a consideration of the drawing and ensuing descriptions.
DESCRIPTION OF DRAWINGS
FIG. 1 is a side view of the preferred embodiment with portions thereof broken away to show the interior.
FIG. 2 is an enlarged frontal view of an alternative forward surface of the invention incorporating a control switch panel which allows space for inclusion of a headlamp or like lighting means.
FIG. 3 is an enlarged side view showing an alternative water intake channel at the back end of the propulsion device.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the preferred embodiment of the invention. The invention has a watertight housing 4 and is shaped substantially cylindrical and allows space inside for a battery 6 to drive motor 7 as controlled by an on/off motor switch 2 at the front end of the unit.
The propeller shaft 9 is an extension of motor 7 and protrudes through a rotary seal 8 to prevent water from entering the housing. The shroud mount 15 extends from the back of housing 4 to the propeller shroud 3 thereby holding said propeller shroud securely in place. The propeller is attached at the end of propeller shaft 9. The space between the shroud mounts 15 and the propeller shaft 9 in front of propeller shroud 3 acts as the water intake channel 11.
The watertight housing unit 4 has connected to it a multiplicity of attachment straps 1 which are arranged perpendicularly to the horizontal length of the watertight housing 4.
The nesting protuberances 5 are designed to be an integral part of watertight housing 4 to facilitate comfort and security when the invention device is attached to a users forearm.
An alternative configuration of control options is shown at the front end of the watertight housing 4, FIG. 2. A speed control 12 is placed near the on/off motor switch 2. Furthermore a lamp switch 13 controls electric lamp 14 for purposes of night time use or deep diving in dark areas.
FIG. 3 shows an alternative propeller shroud 3 with a ramification on the original water intake channel 11 shown in FIG. 1. The water intake channel 11 shown in FIG. 3 protrudes sideways and so scoops in more water in order to increase propeller thrust efficiency. In addition FIG. 3 shows the back end of watertight housing 4 as well as a shroud mount 15 which holds propeller shroud 3 in place.
The drawing reference numerals will be discussed individually as to function and variation of embodiments and design ramifications.
1 strap attachments--are made of suitably wide nylon fabric with a plastic buckle on one end and adjoining velcro type fasteners sewn on the top surface of the other end. The velcro end is pulled through the buckle loop until snugly tightened and then pressed down firmly back over itself and thereby held firmly by the said velcro strips to prevent slippage. The velcro strips are long enough to allow for enough adjustment flexibility so as to accommodate a range of small to large forearms of users. Variations on materials of straps would include fibers, fabric, cloth, canvass, rubber, plastics, metal or a combination of the like.
Mechanical variations of strap buckling or fastening systems may also include employment of bindings, zippers, ties, hitches, chains, flexibands, yokes, brackets, clasps, laces, clamps or a combination of the like.
Any of the above mentioned straps may be designed as either separate pieces as shown in FIG. 1 or made to completely encircle the entire unit as one continuous piece.
2 on/off motor switch--is comprised of a direct current toggle switch covered by a watertight boot to prevent water entry into the housing. Variations of such switch would include a turn on/off switch or a push on/push off type switch. More sophisticated ramifications might include forms of electronically operated magnetic or touch sensor activated switches.
3 propeller shroud--is made of aluminum with a Kort nozzle type intake and exit formation. Variations on materials could include but not be limited to plastics, fiberglass, stainless steel, hardened rubber or similar resins and the like.
4 watertight housing--is made of PVC plastic. It is therefore very lightweight, watertight and strong to withstand the great pressures of deep diving environments. The housing may also be constructed of such materials or combinations thereof as other plastics such as ABS, resins or metals accomplishing the purposes of being generally rust proof, having great strength and a minimum of weight.
5 nesting protuberance--is human engineered to provide for a range of forearm sizes of users. A gentle concave wedge shaped indentation is constructed along top side of watertight housing 4. Although nesting is not absolutely necessary to functional operation of the device, any sort of protuberances would generally assist the user in terms of comfort and anti-slippage security.
6 battery--a custom nickel-cadmium pack is used at 10 volts with 7 ampere hours of discharge capacity. The nicads are rechargeable and may be used several hundred times for over a period of 2 years. Other batteries may be used within the scope of rechargeability, compactness, power output parameters and economy of use.
7 motor--a 12 volt direct current single shaft motor is used in the preferred embodiment. However, any type motor in terms of torque, rpm, weight, size and type of materials may be utilized as to satisfy the purpose of driving a propeller efficiently through water and simultaneously provide the desired levels of thrust required to propel a swimmer or diver through the water. 8 rotary seal--device uses a conventional single lip seal. A similar spring loaded seal or two such seals back to back would provide a more secure lip. A double lip seal system may also be used.
9 propeller shaft--is made of stainless steel and extends far enough to reach at least beyond the center of propeller shroud 3.
10 propeller--is approximately 3 inches in diameter keeping within the inventions spirit of compactness. The propeller utilizes 3 blades for maximum efficiency and minimum vibration. The propeller is made of brass and secured by a nut. The propeller may take on a larger diameter and may also be fashioned of rust proof metals or even a variety of plastics. Various pitches of props could be made available to meet the needs of a variety of speed and task requirements.
11 water intake channel--naturally surrounds inward areas between the shroud mounts 15 to admit water toward the propeller 10. A variation is shown in FIG. 3 whereby additional water intake channels are provided by the placement of a scoop or cowl protruding beyond the surface of the housing. Such as mentioned scoops or cowls may be in a few sections or a continuous piece surrounding the entire propeller shroud unit. A grille or strainer may be placed at the front end of the water intake channel 11 (FIG. 3) to prevent debris from clogging the shroud and or fouling the propeller.
12 speed control--incorporates a pulse width modulator controlled by a push button step up (looped to) step down amperage draw circuit. This in effect controls rpm of the dc motor and hence makes it possible to adjust the speed of units. A ramification includes having one or more preset options on a voltage bypass as conventionally used with resistor and transistors. The pwm, pulse width modulator, is currently easily available, and is also the state of the art in small dc type controlling of said motor speeds. The term "control switch" as used herein includes either on/off switch 2 only, or on/off switch 2 in conjunction with speed control 12.
13 lamp switch--is set up same way as motor on/off switch as described in item 2 above. Preferably an on/off push button switch is used and hooked up in series with lamp and battery.
14 electric lamp--any lamp drawing generally from 1/2 to several ampere hours of power may be incorporated, depending on the need of brightness and use or need of the particular swimming or diving task.
15 shroud mounts--are fashioned of aluminum to provide strength, rust proof ability and benefit of being light weight. Strong plastics would also be an ideal alternative to metal materials.
Those skilled in the art will envision many other possible variations within the spirit and scope of my invention.
The front end of housing 4 could have a removable nose cap or cone for easy service access to controls, battery and motor for maintenance and repairs. On the side or top of unit an external recharge port may be mounted so as to recharge batteries quickly and conveniently.
A pressure leak test valve could be mounted in a convenient out of way place for checking tightness of all sealing systems that any embodiments might prefer to engage.
It is further suggested that a strobe or blinking type light system be incorporated to aid in night time navigation so divers might keep track of their team members. Such a mentioned strobe or beacon light(s) could be mounted on one or a plurality of sides per unit to increase visual ability and effectiveness.
Another important ramification includes the concept of hooking up the invention device to an external power supply via an optional plug-in power cord. Thereby user is allowed added power and time for extended operations or as a reserve backup. Such accompanying external battery supply would be strapped to the divers waist or strapped to his breathing tank(s).
The scope of the invention is to be determined by the appended claims and their legal equivalents, and not solely by the illustrations, embodiments, examples and ramifications that have been presented within these specifications. | A motorized propulsion device for swimmers and scuba divers which is to be attached to the user's forearms. The battery, motor, propeller and propeller shroud are arranged in a compact, linear, hydrodynamic manner. The watertight housing may have one or more integrally shaped nesting protuberances to comfortably accommodate the user's forearm and thereby prevent slippage. The front end surface of the housing has a control panel within reach of the user's fingers. | 0 |
CROSS REFERENCE APPLICATION
This application is a division of application Ser. No. 542,621, filed June 25, 1990, now U.S. Pat. No. 5,061,799.
FIELD OF THE INVENTION
This invention relates to an improved method for the preparation of tetraazaindenes and to intermediate compounds prepared for use therein.
BACKGROUND OF THE INVENTION
It is known that tetraazaindenes and their salts represented by the general structural formula ##STR4## wherein M is a metal cation selected from Group IA and IIA metals and y is the valence of the metal cation, are useful as stabilizers in photographic emulsions. For example, it is known that in a silver halide emulsion there is a detectable amount of the silver salt reduced during development in the unexposed areas. The result can be degradation of the photographic image. It is well known that the presence of tetraazaindenes in the silver halide emulsion can decrease the degradation of the developed photographic image. Accordingly, there has been considerable effort expended in the art to prepare tetraazaindene compounds.
Prior workers have shown that the preparation of tetraazaindenes is not an easy task. Several approaches have been taken by prior workers to overcome this problem.
One prior art approach ("prior art approach 1") to prepare tetraazaindenes is by the condensation of a β-keto ester, a malonic ester or a mononitrile of a malonic ester, with a 3-amino-1,2,4-triazole. One problem with this approach is that preparation of the β-keto ester for the reaction can be inefficient in regard to yield and the β-keto ester can decompose and consequently result in a reduced overall reaction product yield. Another problem is that the time involved for the reaction to yield a commercial amount of tetraazaindene is lengthy and thus involves a significant manufacturing process cost. A third problem is that undesirable intermediate compounds that are unstable and difficult to isolate are formed, necessitating an additional purification step or steps and negatively effecting the process times, cost, and yield.
Another prior art approach ("prior art approach 2") is to condense a triazole or a polyazole having at least one primary amino group with a β-keto ester, a β-keto acetal, a cyclic β-keto ester, or a malonic or cyanacetic ester. This approach likewise has all the above-stated problems that can result in increased process times and costs and decreased yield of tetraazaindenes.
A third prior art approach ("prior art approach 3") results in a tetraazaindene having a carboxyl group by deesterification of the tetraazaindene, said tetraazaindene having been prepared by condensing an alkoxymethenemalonic acid ester with a 3-amino-1,2,4-triazole compound under alkaline conditions. The free acid form is obtained by acidification of the deesterified tetraazaindene. This process not only has the above-described problems of the prior art processes but it involves the additional process step of deesterification followed by acidification, thus further increasing the process time, process steps, and process costs.
This invention solves the prior art problems noted above. It does not generate unstable and difficult to isolate intermediate compounds. Instead, intermediates are produced that react faster and more completely, thus eliminating the costly and time-consuming step or steps of isolation and purification associated with unstable intermediate compounds.
Furthermore, the reaction conditions of this invention are milder and result in increased yield of the tetraazaindene. Also, the reactions take place faster and thus involve decreased process costs. Thus, by means of this invention, there is provided an improved, three-step synthesis of tetraazaindenes that solves the above-stated prior art problems.
RELATED ART
U.S. Pat. No. 2,444,605 (prior art approach 1) discloses photographic silver halide emulsions containing tetraazaindenes prepared by condensation of a β-keto ester, a malonic ester or a mononitrile of a malonic ester, with a 3-amino-1,2,4-triazole.
U.S. Pat. No. 2,566,659 (prior art approach 2) discloses photographic silver halide emulsions containing tetraazaindenes prepared by reacting 2-amino-5-methylmercapto-1,3,4-triazole or a 2-amino-5-mercapto-1,3,4-triazole with a β-ketonic ester, a cyclic β-keto ester, or a malonic or cyanacetic ester.
U.S. Pat. No. 2,837,521 (prior art approach 2) discloses a process for preparing polyazaindene compounds by condensing β-ketoacetals and polyazole compounds having at least one attached primary amino group.
U.S. Pat. No. 2,933,388 discloses tetraazaindenes prepared by the condensation of 3-amino-1,2,4-triazoles with acylacetic esters.
U.S. Pat. No. 3,202,512 (prior art approach 3) discloses photographic silver halide emulsions containing tetraazaindenes prepared by the condensation of alkoxymethylenemalonic acid ester with a 3-amino-1,2,4-triazole under alkaline conditions is unstable and not easily isolable. The reference discloses that the tetraazaindene compound having a carbalkoxyl group can be deesterified to a carboxyl group. The free acid can then be obtained by acidification. The patent also discloses that the carboxylated tetraazaindene may be acidified to prepare the free acid form.
U.S. Pat. No. 4,728,601 (prior art approach 1) discloses the preparation of ballasted tetraazaindenes by reacting a triazole with a β-keto ester.
BRIEF DESCRIPTION OF THE DRAWING
The drawing illustrates a sequence of reactions in the process of this invention. According to convention, methyl groups are not shown at the end of the unsatisfied valence lines. Also, in the drawings, "EtOAc" is ethyl acetate. Three reactions are illustrated and are labelled steps, 1, 2 and 3, and correspond to Examples 1, 2, and 3, respectively, in the specification. The compounds dimethyl-5-(1-ethoxyethylidene)-2,2-1,3-Dioxane-4,6-Dione and 2,2-dimethyl-5-(1-((5-(methylthio)-1H-1,2,4-triazol-3-yl)amino)ethylidene)-1,3-dioxane-4,6-dione formed in steps 1 and 2 and labelled "A" and "B" respectively in the drawing require no further purification or isolation steps. The end reaction product shown in step 3 and labelled "C" is 5-carboxy-4-hydroxy-6-methyl-2-(methylthio)-1,3,3A,7-tetraazaindene. The reaction product of step two is unstable and not easily isolable. The reaction products of steps 2 and 3 show good stability and product yield.
SUMMARY OF THE INVENTION
The invention provides a new method, more cost-efficient than prior art methods, for preparing the tetraazaindenes of Formula I. The new method comprises a multi-step process that includes new intermediate methods and compounds. The new intermediate compounds require no purification or isolation step but can be directly reacted to provide a good yield of tetraazaindene in comparison with the method of the prior art.
One of the new methods of the invention is a method, hereinafter referred to as step one, for preparing a novel first intermediate compound represented by the structural formula ##STR5## The method of step one comprises reacting a compound represented by the structural formula ##STR6## wherein R 3 and R 4 are independently selected from alkyl groups having up to about 4 carbon atoms with an orthoester represented by the structural formula R 1 --C(OR) 3 wherein R is an alkyl group having up to about 4 carbon atoms and R 1 is selected from straight chain alkyl groups and aryl groups having up to about 8 carbon atoms to form the first intermediate of Formula II. The reaction of step one takes place in the presence of (a) a catalytic amount of a tertiary amine having a pKa sufficient to catalyze the reaction and (b) a substantially anhydrous organic solvent.
Another of the new methods of the invention is a method, hereinafter referred to as step two, for preparing a novel second intermediate compound represented by the structural formula ##STR7## wherein R 2 is an alkyl or aryl group having up to about 8 carbon atoms and R 1 , R 3 , and R 4 are as described above. The method of step two comprises reacting the new first intermediate compound of Formula II with a triazole represented by the structural formula ##STR8## to form a composition containing the compound of Formula III.
A third method of the invention, hereinafter referred to as step three, comprises reacting the new second intermediate compound of Formula III with a base to form a tetraazaindene salt represented by the structural formula ##STR9## wherein M is a metal cation selected from Group IA and IIA metals and y is the valence of the metal cation. In a preferred embodiment, hereinafter referred to as step four, an acid is added to the tetraazaindene salt of Formula I to form the tetraazaindene by substituting a hydrogen or hydrogens for M, thereby forming a carboxyl group (COOH) on each such tetraazaindene group.
Another method of the invention comprises a sequential combination of step one and step two described above, that is, starting with the reactants of step one and forming the intermediate compound of Formula II which is then reacted as described in step two to form the intermediate compound of Formula III.
In another method of the invention, a sequential combination of step two and step three described above form the compound of Formula I starting with the reactants of step two.
Another method of the invention comprises a sequential combination of steps one, two, and three to form the compound of Formula I.
In any of the stated methods of the invention that form the compound of Formula I, step four described above may then be conducted to form the related tetraazaindene.
The methods of this invention are conducted at reaction conditions such as pH and temperature and the like that produce a good yield and product stability for the individual or sequential step method. The tetraazaindenes thus produced are useful as image toners or stabilizers in silver halide photographic emulsions to improve the exposed film resistance to fogging and the like. Tetraazaindenes generally are manufactured, packaged and stored in the crystalline form. The tetraazaindene may then be rendered water-soluble by conversion to the salt to facilitate its use in manufacturing photographic emulsions.
DESCRIPTION OF PREFERRED EMBODIMENTS
A preferred method of the invention, hereinafter referred to as step one, comprises the preparation of a compound represented by the structural formula ##STR10## wherein R is an alkyl group having up to about 4 carbon atoms, R 1 is selected from straight chain alkyl groups and aryl groups having up to about 8 carbon atoms, and R 3 and R 4 are independently selected from alkyl groups having up to about 4 carbon atoms, by reacting a compound represented by the structural formula ##STR11## wherein R 3 and R 4 are as above-described with an orthoester represented by the structural formula R 1 --C(OR) 3 wherein R and R 1 are as above-described, in the presence of a) a catalytic amount of a tertiary amine having a pKa sufficient to catalyze the reaction, and b) a substantially anhydrous organic solvent, to form said compound II. In a preferred embodiment, R 3 and R 4 are both methyl.
In another preferred embodiment of the invention, hereinafter referred to as step two, a compound of Formula II is reacted with a triazole represented by the structural formula ##STR12## wherein R 2 is an alkyl or aryl group having up to about 8 carbon atoms to form a composition containing a compound of Formula III. In a preferred embodiment of the compound of Formula III, R 1 and R 2 are each a straight chain alkyl group of up to about 8 carbon atoms.
In yet another preferred embodiment of the invention, hereinafter referred to as step three, a compound of Formula III is reacted with a base to form a tetraazaindene salt represented by Formula I.
Another preferred embodiment of the invention is a sequential combination of steps one and two to form a compound of Formula II. Another preferred embodiment is a sequential combination of steps two and three to form a compound of Formula I.
A particularly preferred embodiment comprises a sequential combination of steps one, two and three to form a compound of Formula I. For example, a particularly preferred tetraazaindene salt of Formula I comprises both R 1 and R 2 as methyl groups and X as hydrogen. In accordance with such preferred embodiment, in the multi-step process of the invention, cyclic dimethylmethylene malonate, commonly known and referred to by those skilled in the art as Meldrum's acid, is a preferred reactant wherein both R 3 and R 4 are methyl in Formula IV of step one. Meldrum's acid is a readily available and cost-effective compound, and is prepared by methods well-known in the art. See, for example, Meldrum, J. Chem. Soc., 93, 598 (1908); see also "Organic Reactions," John Wiley and Sons, Inc., New York, N.Y., 1946, Vol. III, p. 124. In practicing the broader scope of the invention, the preparation of compounds related to Meldrum's acid by employing related starting materials is also well within the skill of the art.
A preferred orthoester of formula R 1 --C(OR) 3 in step one comprises triethylorthoacetate wherein R 1 is methyl and R is ethyl. In a particularly preferred embodiment, Meldrum's acid is reacted with triethylorthoacetate to form the compound of Formula II wherein R 1 is methyl, R is ethyl, and R 3 and R 4 are both methyl.
Preferred tertiary amines in step one include triethylamine, polyvinylpyridine, and 1,8-diazabicyclo-(5.4.0)undec-7-ene. A particularly preferred tertiary amine in step one is pyridine. The tertiary amine employed as the catalyst in step one should be used in a catalytic amount and having a pKa sufficient to catalyze the reaction of step one. It is within the skill of one of ordinary skill in the art of organic chemistry or the art of organic compound synthesis to determine the amount of tertiary amine to use as the catalyst and to determine the pKa of the tertiary amine sufficient to catalyze the reaction. For example, the selected catalytic amount of tertiary amine can be dependent on the particular reactants of the invention that are selected and also can be dependent on the weight quantities of the reactants. Thus, as the weights of the reactants of step one are increased the catalyst amount of tertiary amine will also increase. A preferred weight proportion of tertiary amine to the reactant having the formula R 1 --C(OR) 3 as defined hereinabove can be in the range of about 0.01:1 to about 0.2:1 with respect to either reactant. Generally, a catalytic amount of tertiary amine can comprise an amount nearer the low end of the range if it has a pKa higher than a tertiary amine of the invention requiring a higher catalytic amount within the above range. For example, when the tertiary amine comprises pyridine of a pKa of about 5.2, and the reactants are triethylorthoacetate and 2,2-Dimethyl-m-dioxane-4,6-dione in the respective weight proportion of about 1.12:1, then a catalytic amount of the pyridine can comprise a relative weight proportion to the respective two reactants above of about 0.09:1.12:1 respectively.
Likewise, the pKa of the tertiary amine sufficient to catalyze the reaction is within the skill of one of ordinary skill in the art and can be determined without undue experimentation for the particular reactants of the invention selected and for a selected reaction condition as set forth herein. A preferred pKa is about 5 to about 7.
A preferred anhydrous solvent in step one is toluene and a particularly preferred anhydrous solvent is ethyl acetate. Other anhydrous solvents such as methylene chloride and acetic acid may be employed but do not provide as good reaction times and product yield because the above stated such preferred solvents have a polar character and have sufficient solvent power to produce good reaction times and product yield for the step one reaction. The use of methylene chloride also involves environmental concerns with atmospheric emissions and the related economic costs.
The reaction of step one preferably takes place at a temperature of from about 0° C. to about 50° C. A particularly preferred reaction temperature is about 50° C. A preferred reaction pressure is ambient pressure although step one can be conducted at a pressure from below ambient pressure to about 100 psig.
In step two, a preferred triazole is 3-amino-5-methylthio-1,2,4-triazole. For example, the preferred triazole can be reacted with a Formula II compound wherein R 1 is methyl and R is ethyl to form a composition containing a compound of Formula III wherein R 3 and R 4 are both methyl and R 1 and R 2 are both methyl.
It is preferable to carry out the reaction of step two in the same solvent as step one although a different but appropriate solvent can be readily selected by the skilled practitioner.
In step two, the reaction preferably takes place at a temperature of from about 0° C. to about 25° C. A particularly preferred reaction temperature is about 25° C. A preferred reaction pressure is ambient pressure although step three can be conducted at a pressure from below ambient pressure to about 100 psig.
A preferred base in step three is a Group IA or IIA metal hydroxide or carbonate. Particularly preferred bases include sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, potassium carbonate, and mixtures thereof. A preferred reaction pH is about 9. In a particularly preferred embodiment of step three, a compound of Formula III wherein R 3 and R 4 are both methyl and R 1 and R 2 are both methyl is reacted with sodium carbonate to form a compound of Formula I wherein R 1 and R 2 are both methyl, M is sodium, and y has a value of one.
Step three is conducted in an aqueous solution whereas step one and step two are conducted under substantially anhydrous conditions in order to maximize the product yield for the particular step. In a preferred embodiment, ethyl acetate is dried with magnesium sulfate and then employed as the solvent in step one and step two. This expedient is exemplified in Example 1.
In step three, the reaction preferably takes place at a temperature of from about 0° C. to about 50° C. A particularly preferred reaction temperature is about 50° C. A preferred reaction pressure is ambient pressure although step three can be conducted at a pressure from below ambient pressure to about 100 psig.
The reaction time for each of the steps of the process of the invention is not a truly independent variable and is dependent at least to some extent on the inherent reactivity of the reactants of the step and also in the reaction temperature for the step. In general, the higher the temperature and the more active the reactants employed, the shorter the reaction time. Thus, the time of reaction is not critical so long as it is sufficient for reaction to take place. In general, the multi-step process is complete in about 8 to about 16 hours. The time of reaction for each step can be readily determined by a skilled practitioner using known techniques.
The amount of solvent employed is not critical. In general, one employs enough solvent to dissolve the product(s) and reactant(s) to an appreciable extent. There is no real upper limit on the amount of solvent employed. This is generally influenced by the size of the reaction vessel, process economics, and similar secondary considerations.
As stated hereinabove, it is not necessary that the same solvent be present throughout the process. For example, after step one, one may change solvents prior to resuming step two. Thus, for example, one may wish to change the solvent (a) because it is too volatile at an increased reaction temperature used at a latter stage of the process, or (b) when the solvent becomes incapable of dissolving the product being produced.
Step one and step two in the process of this invention are conducted in the substantial absence of water, that is, under substantially anhydrous conditions. The product yield of step one and step two is thereby optimized and step one and step two are therefore each more commercially viable. For example, if the moisture content of the orthoester of formula R 1 --C(OR) 3 of step one as defined above is above the preferred limits as set forth herein (infra) then the reactant of Formula IV as defined above can decompose, thus lowering the product yield of step one. Stated another way, a skilled practitioner (familiar with the aromatic reactions such as substitution, addition and/or ring closures) will appreciate that step one and step two of the process of this invention are conducted under substantially dry conditions in order to improve the yield of desired product. For example, an operator may wish to employ ethyl acetate as the solvent in the multi-step process of this invention, and prior to using it the operator may proceed to dry the solvent with magnesium sulfate. Preferably, the water content is less than about 0.5 weight percent. It is particularly preferred that the water content is less than about 0.1 weight percent. It is, however, preferable to conduct step three in an aqueous solution. This multi-step expedient is exemplified in the examples.
In any of the above-described methods of the invention that result in forming a compound of Formula I, a preferred embodiment is to conduct an additional step, hereinafter referred to as step four, in which compound I is reacted with an acid to form a tetraazaindene by substituting a hydrogen or hydrogens for M, thereby forming a carboxyl group (COOH) on each such tetraazaindene group.. A preferred acid is hydrochloric acid and a preferred reaction pH is about 1.
All preferred conditions, reagents, etc, for the above-described sequential step methods are the same as those recited previously in the detailed description, hereinabove, of those steps as individual inventive methods.
The following Examples are presented to further illustrate some preferred embodiments of the invention.
(Where quantities, below, are expressed as "parts" this means parts by weight.)
EXAMPLE 1
Preparation of dimethyl-5-(1-ethoxyethylidene)-2,2-1,3-dioxane-4,6-dione
A suitable vessel was placed on a nitrogen purge and 938 parts of ethyl acetate was introduced and stirred. A quantity of 22.68 parts of magnesium sulfate was then added to the vessel and the contents were stirred for 15 minutes at 25° C.
The ethyl acetate was then removed and dried by twice circulating the vessel contents through a filter press, after which the dried ethyl acetate was introduced back to the vessel. A sample of the ethyl acetate showed a water content of less than 0.1 weight percent. A quantity of 250 parts of 2,2-Dimethyl-m- dioxane-4,6dione was then added to the vessel. By vacuum suction 281 parts of triethylorthoacetate was then introduced to the vessel. 22.6 parts of pyridine was then added to the vessel and a nitrogen purge placed on the vessel. The contents of the vessel were then heated to 50° C. and stirred for 2 hours. Fourier Transform Infrared Spectroscopy (FTIR) demonstrated the reaction mixture contained dimethyl-5-(1-ethoxy-ethylidene)-2,2-1,3-dioxane-4,6-dione.
EXAMPLE 2
Preparation of 2,2-dimethyl-5-(1-((5-(methylthio)-1H1,2,4-triazol-3-yl)amino)ethylidene)-1,3-dioxane-4,6dione
The method of Example 1 was carried out and a suitable vessel was charged with the dimethyl-5-(1-ethoxyethylidene)-2,2-1,3-dioxane-4,6-dione product of Example 1 and 156 parts of 3-amino-5-(methylthio)-1,2,4-triazole. The reaction mixture was stirred at 25° C. for 1 hour, cooled to 5° C., and stirred at 5° C. for 1 hour.
To a second vessel dry, and on a nitrogen purge, was introduced 446 parts of isopropyl alcohol which was then stirred at 0° C.
The reaction mixture of the first vessel was then centrifuged and the precipitate was washed with the isopropyl alcohol. The reaction product was dried at 30° C. High pressure liquid chromatography, nuclear magnetic resonance method, and mass spectrometry analysis demonstrated the reaction product was 2,2-dimethyl-5-(1-((5-methylthio)-1H-1,2,4-triazol-3-yl)amino)-ethylidene)-1,3-dioxane-4,6-dione. The yield was about 250 parts or 70% maximum theoretical yield.
EXAMPLE 3
Preparation of 5-carboxy-4-hydroxy-6-methyl-2-(methylthio)-1,3,3A,7-tetraazaindene
The method of Example 2 was carried out to produce 250 parts of 2,2-dimethyl-5-(1-((5-methyl- thio)-1H-1,2,4-triazol-3-yl)amino)ethylidene)-1,3-dioxane-4,6-dione. A suitable vessel was placed on a nitrogen purge and 1000 parts of distilled water was added to the vessel. 105 parts of sodium carbonate was added to the vessel and the contents stirred at 40° C.
The 250 parts of 2,2-dimethyl-5-(1-((5-methylthio)-1H-1,2,4-triazol-3-yl)amino)ethylidene)-1,3-dioxane-4,6-dione was introduced to the vessel and the reaction mixture was stirred at 50° C. for 30 minutes. The reaction mixture was filtered and then stirred while cooling to 5° C.
Hydrochloric acid was then added to the reaction mixture, lowering the pH to 1 and resulting in a thick slurry. The slurry was stirred at 5° C. for 30 minutes, and the reaction product was then collected by centrifuge. The reaction product was washed with filtered, cold water and then dried at 60° C. High pressure liquid chromatography, nuclear magnetic resonance method, and mass spectrometry analysis showed the reaction product was 5-carboxy-4-hydroxy-6-methyl-2-(methylthio)-1,3,3A,7-tetraazaindene. The yield was 185 parts or 92% maximum theoretical yield. In terms of the sequential process of conducting step one, then step two, and then step three with the reactants specified in Example 3, the overall process yield was 64.3% of the maximum theoretical yield.
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. | A multi-step process for the preparation of tetraazaindenes provides new, intermediate compounds and methods for their formation. A first method or step (1) of the process comprises reacting Meldrum's acid (cyclic dimethylmethylene malonate) or a related compound with an orthoester to form a first intermediate. Another method or step (2) of the invention comprises reacting the first intermediate with a triazole to form a second intermediate. A third method or step (3) comprises reacting the second intermediate with a base to form a tetraazaindene salt from which the tetraazaindene can then be formed. Other methods of the invention comprise sequential combinations of the three new methods above described. For example, Meldrum's acid is reacted with triethylorthoacetate in the presence of pyridine and ethyl acetate to form a first intermediate represented by the structural formula ##STR1## The first intermediate is then reacted with 3-amino-5-methylthio-1,2,4-triazole to form a second intermediate represented by the structural formula ##STR2## Upon reaction with sodium carbonate, a tetraazaindene having the formula ##STR3## is produced. Other related compounds are formed when reactants related to those set forth above are employed. Tetraazaindenes are useful as photographic chemicals, for example, as image toners or stabilizers in photographic emulsions. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mounting system for an adjustable article supporting member in a refrigerator, and more particularly to such a system that includes first and second adjustable support members, mounted on opposite sides of a refrigerator compartment, each support member having a track for slidably receiving a side of a refrigerator shelf or a side of a storage bin therein; wherein, the track of the first support member permits lateral movement of the refrigerator shelf or storage bin and the track of the second support member substantially prevents lateral movement of the refrigerator shelf or storage bin so as to securely support the refrigerator shelf or storage bin and allow the shelf or bin to be pulled out smoothly by accommodating dimensional variations in the refrigerator compartment.
2. Description of the Prior Art
Mounting systems for adjustable refrigerator shelves are known to include elongated support members mounted, for example, on the rear wall of the refrigerator compartment liner, wherein, each support member includes a number of vertically aligned slots. Hooks extending from the rear of a refrigerator shelf are inserted into horizontally aligned slots of two support members to removably secure the refrigerator shelf in the refrigerator compartment. A similar refrigerator shelf mounting system is shown in U.S. Pat. No. 4,365,152 vertically elongated tracks having an S-shaped cross-section abut the rear wall of a refrigerator compartment while being secured to a sidewall thereof. The tracks include a number of slots for receiving a hook extending from a bracket secured to a refrigerator shelf to mount the refrigerator shelf in the refrigerator compartment. Although this type of mounting system allows a refrigerator shelf to be mounted at various heights within the refrigerator compartment, the refrigerator shelf cannot be pulled out. Because the refrigerator shelf cannot be pulled out, articles located at the rear of the refrigerator shelf may be difficult to reach.
U.S. Pat. No. 682,035 shows a refrigerator shelf support system that includes a pair of rear upright supports having a series of slots therein, the rear upright supports being mounted on a rear wall of a refrigerator compartment. A pair of front upright supports are mounted on a front wall of the refrigerator compartment, the front upright supports also having a series of slots therein. Horizontally extending shelf supports are provided with a flange at the front and rear thereof for insertion into respective slots in the front and rear upright supports. Each of the shelf supports includes a track into which a side of a refrigerator shelf is inserted so as to mount the refrigerator shelf in the refrigerator compartment. As shown therein, the refrigerator shelf fits snugly in each track of the shelf supports so as to prevent lateral movement of the shelf.
Liners of refrigerator compartments are now typically formed of plastic so that dimensional variations in the refrigerator compartment, such as the width of the compartment, must be accounted for when mounting refrigerator shelves therein. The dimensional variations of the refrigerator compartment liner typically do not become apparent until operation of the refrigerator making it difficult to provide a refrigerator shelf mounting system that provides positive support and allows a refrigerator shelf to be smoothly pulled out.
SUMMARY OF THE INVENTION
In accordance with the present invention, the disadvantages of refrigerator shelf mounting systems as discussed above, have been overcome. The mounting system of the present invention includes first and second support members each of which is removably secured to a respective pair of studs mounted on opposite sidewalls of the liner of a refrigerator compartment so that the height of the support members may be adjusted. Each of the first and second support members includes at least one track wherein the tracks receive opposite sides of a refrigerator shelf or storage bin for slidable movement therein. The track of the first support member permits lateral movement of the refrigerator shelf or storage bin; whereas, the track of the second support member substantially prevents lateral movement of the refrigerator shelf or storage bin to positively support the refrigerator shelf or storage bin in the refrigerator compartment and to allow the refrigerator shelf or storage bin to be pulled out smoothly by accommodating dimensional variations in the liner of the refrigerator compartment.
More particularly, the mounting systems of the present invention includes a first pair of horizontally aligned studs mounted on a first sidewall of the refrigerator compartment liner with one stud being positioned toward the rear of the refrigerator compartment and the other stud being positioned towards the front of the refrigerator compartment. A second pair of horizontally aligned studs are mounted on a second sidewall of the refrigerator compartment liner at the same height as the first pair of studs wherein the second pair of studs similarly includes a rearwardly positioned stud and a forwardly positioned stud. A first support member has an elongated sidewall with a rearwardly positioned slot and a forwardly positioned slot formed in the backside of the sidewall to respectively engage a rearwardly and forwardly positioned stud of the first pair of studs. The first support member also includes an upper flange extending generally horizontally from a front side of the support member's sidewall along the length thereof and a lower flange that extends generally horizontally from the front side of the sidewall along the length thereof and spaced a distance below the upper flange to form a track therebetween. A second support member is similarly provided with a rearwardly positioned slot and a forwardly positioned slot formed in the backside of the sidewall of the support member wherein the forwardly and rearwardly positioned slots respectively engage the forwardly and rearwardly positioned studs of the second pair of studs. The second support member further includes an upper flange and a spaced lower flange to form a track therebetween wherein one or more projections extends upwardly from an outer edge of the lower flange.
The tracks of the first and second support members receive opposite sides of a refrigerator shelf or storage bin to slidably mount the refrigerator shelf or storage bin in the refrigerator compartment. More particularly, the tracks receive opposite sides of a picture frame extending about the periphery of the refrigerator shelf or opposite sides of a rim framing the upper surface of a storage bin. The projection(s) extending upwardly from the lower flange of the second support member abuts the inner surface of the refrigerator shelf frame or storage bin rim received in the track of the second support member to substantially prevent lateral movement of the refrigerator shelf frame or storage bin rim received therein. The first support member, however, permits lateral movement of the opposite side of the refrigerator shelf frame or storage bin rim so as to accommodate dimensional variations in the liner of the refrigerator compartment.
The rearwardly positioned slot of each support member is U-shaped, opening towards the rear end of the support member and extending forwardly therefrom. The forwardly positioned slot of each shelf support member is also U-shaped. However, the forwardly positioned slot opens from a lower edge of the support member and extends upwardly therefrom. To mount the shelf support member on a sidewall of the refrigerator compartment liner, the support member is moved rearwardly along the wall of the liner at an angle such that the front end of the support member is above the rear end thereof until the rearward slot of the shelf support member engages a rearwardly positioned stud mounted on a sidewall of the refrigerator compartment liner. Thereafter, the shelf support member is pivoted about the rearwardly positioned stud, moving the front end of the support member downward until the forwardly positioned slot engages the forwardly positioned stud mounted in the refrigerator compartment liner. This method of mounting a shelf support member in the refrigerator compartment substantially prevents accidental disengagement of the shelf support member during normal use of the shelf.
Each of the studs is a dovetail stud; whereas each of the slots in the support members is a dovetail slot. Each slot engages a stud, on three sides thereof to make a strong joint. Further, each stud has a rounded upper and lower edge so as to permit a shelf support member to be pivoted about a stud.
A first double track support member and a second double track support member are further provided to support a refrigerator shelf as discussed above and to further support a storage bin or the like beneath the refrigerator shelf. More particularly, the sidewall of each double track support member includes four flanges extending generally horizontally from a first side of the sidewall. The two uppermost flanges of the first and second double track support members are formed in the same manner as the upper flange and lower flanges of the respective first and second single track support members described above to provide upper tracks for supporting a refrigerator shelf. The two lowest flanges extending from the sidewall of each double track support members form a lower track in which a side of an upper rim of a storage bin is slidably received. The lowest flange of the second support member is formed with one or more projections extending upwardly from an outer edge thereof, so as to prevent lateral movement of the side of the storage bin rim received therein. The lower track of the second double track support member, however, permits lateral movement of the opposite side of the storage bin rim received therein to accommodate dimensional variations in the refrigerator compartment liner. Each double track support member includes a rearwardly and forwardly positioned slots in the backside of its sidewall wherein the slots are the same as those formed in the single track support members so as to enable a double track support member to be mounted in the same manner as the single track support member.
A wine rack is further provided which may be mounted on the forwardly and rearwardly positioned studs of a sidewall of the refrigerator compartment liner. The wine rack includes an elongated side flange that extends downwardly into a side of an elongated bottle support member having a generally U-shaped cross-section, the side flange and bottle support member being integrally formed. Generally U-shaped dovetailed slots are formed on the backside of the side flange of the wine rack at a rearward position and a forward position. The rearwardly position slot opens towards the rear of the side flange whereas the forwardly positioned slot opens downwardly in the same manner as the slots formed in the backside of the single track shelf support members discussed above. The slots allow the wine rack to be mounted by moving the wine rack rearwardly along a wall of the refrigerator compartment liner and at an angle with the front end of the wine rack above the rear end thereof until the rearwardly positioned slot engages a rearwardly positioned stud mounted on the liner sidewall. Thereafter, the wine rack is pivoted downward about the rearwardly positioned slot until the forwardly positioned slot engages a forwardly positioned stud to secure the wine rack to a sidewall of the refrigerator compartment liner.
These and other objects, advantages and novel features of the present invention, as well as details of an illustrated embodiment thereof, will be more fully understood from the following description and the drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a refrigerator incorporating the mounting system for article supporting members of the present invention;
FIG. 2 is an inside elevation illustrating a left support member secured to a rearwardly positioned stud and at an angle with respect to the forwardly positioned stud;
FIG. 3 is an inside elevation showing a left support member mounted on a rearwardly and forwardly positioned stud;
FIG. 4 is a front view of a dovetail stud shown in FIGS. 1-3;
FIG. 5 is a side view of the stud shown in FIG. 4;
FIG. 6 is a partial perspective view of the backside of a left support member illustrating a forwardly positioned slot;
FIG. 7 is a perspective view of a right single track support member;
FIG. 8 is a perspective view of a left single track support member;
FIG. 9 is a perspective view of a refrigerator shelf as shown in FIG. 1;
FIG. 10 is a bottom view of the refrigerator shelf shown in FIG. 9;
FIG. 11 is a cross-sectional view taken along lines 11--11 of FIG. 9;
FIG. 12 is a rear end view of a left double track support member;
FIG. 13 is a perspective view of a left double track support member;
FIG. 14 is a perspective view of a right double track support member;
FIG. 15 is a perspective view of a storage bin as shown in FIG. 1;
FIG. 16 is a partial perspective view of the right side of the storage bin shown in FIG. 15 as viewed from the rear and beneath the storage bin;
FIG. 17 is a partial perspective view of the left side of the storage bin shown in FIG. 15 as viewed from the rear and beneath the storage bin; and
FIG. 18 is a perspective view of a wine rack as shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The mounting system of the present invention for adjustable refrigerator shelves 12-16, a wine rack 18 and storage bin 20 is shown in FIG. 1 for a refrigerator 10. The refrigerator 10 includes a refrigerator compartment 22 having a plastic liner 24 therein forming a left sidewall 26, a rear wall 28, and a right sidewall 30 of the compartment 22. Pairs of horizontally aligned studs, only one stud 32-40 of each pair being shown in FIG. 1, are mounted in the left and right sidewalls 26 and 30 of the liner 24 to secure respective left and right single track support members 42 and 44 and left and right double track support members 46 and 48 to the liner sidewalls 26 and 30. The single track support members 42 and 44 slidably mount a refrigerator shelf 12, 14-16 therein; whereas, the double track support members 46 and 48 slidably mount a shelf 13 in an upper track 50, 51 thereof and slidably mount a storage bin 20 in a lower track 52, 53 thereof. The single track support members 42 and 44 and the double track support members 46 and 48 may be mounted on studs at various heights to adjust the height of the shelves 12-16 and storage bin 20. The pairs of studs including the 32, 33, 34 and 39 mounted in the left sidewall 26 of the liner 24 may further be used to secure the wine rack 18 to the liner sidewall 26 as discussed in detail below.
Each of the single and double track support members 42, 44, 46 and 48 includes an elongated sidewall such as the sidewall 54 shown in FIGS. 2, 3, 6 and 8 for the left single track support member 42. On the backside 56 of the sidewall 54 are a pair of slots including a forwardly positioned slot 58 and a rearwardly positioned slot 60. The rearwardly positioned slot 60 is a dovetailed slot having a U-shaped configuration that opens towards the rear end 62 of the left single track support member 42. The slot 60 extends from the rear end 62 forward, towards the front end 63 of the left single track support member 42. The slot 58 is a dovetailed slot with a U-shaped configuration that opens towards the lower edge 64 of the left single track support member 42. The slot 58 extends from the lower edge 64 of the support member 42 upwardly.
Each of the studs 32-40 is a dovetailed stud as shown in detail in FIGS. 4 and 5. Each stud 32-40 includes a dovetailed head 66 having a front face 68 and rear face 70. Extending from the rear face 70 is a centrally located shaft 72 to which metal wires 74 and 76 are attached on opposite sides of the shaft 72 near an end 78 thereof. When a stud, such as the stud 32 is secured to the liner 24 of the refrigerator compartment 22, the metal wires 74 and 76 angle away from the shaft 72 near the head 68 of the stud 32 so as to retain the stud 32 secured to the liner 24. When installed in the liner 24, the studs 32-40 project approximately one-eighth of an inch from the sidewall 26, 30 of the refrigerator compartment liner 24. Further, the head 68 of the each of the studs has a rounded upper edge 80 and a rounded lower edge 82 so as to permit a shelf support member 42, 44, 46, 48 and the wine rack 18 to be pivoted about a stud as described in detail below.
To mount a shelf support member 42, 44, 46 and 48 on a sidewall 26, 30 of the refrigerator compartment liner 24, as shown in FIGS. 2 and 3 for the left single track support member 42, the support member 42 is moved rearward along the sidewall 26 of the liner 24 at an angle such that the front end 84 of the support member 42 is above the rear end 86 of the support member 42. The support member 42 is moved rearwardly as such until the rearward slot 60 engages the rearward stud 88 mounted on the sidewall 26 of the refrigerator compartment liner 24 near the rear of the compartment 22. Thereafter, the shelf support member 42 is pivoted about the rear stud 88, moving the front end 84 of the support member 42 downward until the front slot 58 engages a front stud 90 mounted at a forward position in the sidewall 26 of the refrigerator compartment liner 24. This method of mounting a shelf support member in the refrigerator compartment substantially prevents accidental disengagement of the shelf support member during normal use of the shelf. When the support member 42 is mounted as such on the studs 88 and 90, the slots 60 and 58 respectively engage the studs 88 and 90 on three sides of the stud so as to provide a strong joint.
As shown in FIG. 7, the right single track support member 44 has an elongated sidewall 92. The back-side of the sidewall 92 of the right single track support member 44 is substantially a mirror image of the back-side 56 of the sidewall 54 of the left single track support member 42 with forwardly and rearwardly positioned slots so as to enable the right support member to be mounted on the right sidewall 30 of the liner 24 in the same manner as described above for the left support member 42. An upper flange 94 extends generally horizontally along the length of the support member 44 from a front side 96 of the right support member's sidewall 92. A lower flange 98 extends generally horizontally along the length of the support member 44 from the front side 96 of the sidewall 92 but spaced a distance below the upper flange 94 so as to form a track 97 between the upper and lower flanges 94 and 98. At a forward end 100 of the right single track support member 44, a projection 102 is formed on the lower flange 98, the projection 102 extending upwardly from the lower flange 98 so as to provide a stop for a refrigerator shelf 12, 14-16 as described below.
The left single track support member 42 is similar to the right single track support member 44 in that a generally horizontally extending upper flange 104 and a generally horizontally extending lower flange 106, that is spaced a distance below the upper flange 104, extend from a front side 108 of the sidewall 54 of the left single track support member 42 to form a track 109 between the upper and lower flanges 104 and 106. The lower flange 106 also includes an upwardly extending projection 110 disposed at a forward end 112 of the left single track support member 42 so as to provide a stop for a refrigerator shelf supported therein. The left single track support member 42 differs from the right single track member 44 in that a series of projections 114-116 extend upwardly from an outer edge 118 of the lower flange 106. Further, a small rib 120 is formed on the front face 108 of the left single track support member's sidewall 54 between the upper flange 104 and the lower flange 106 wherein the rib 120 extends the length of the track 109. The upwardly extending projections 114-116 and the rib 120 substantially prevent lateral movement of a refrigerator shelf 12, 14-16 by providing a snug fit therein for the left side 186 of a picture frame 124 of the shelf 12, 14-16 as will be apparent from the description below.
As shown in FIGS. 9-11 for the refrigerator shelf 12, each of the refrigerator shelves 12-16 includes a plate 122 of tempered glass for supporting articles thereon and a rectangular plastic picture frame 124 that extends about the entire periphery of the glass plate 122. The picture frame 124 includes an upper frame 126 and a lower frame 128 that are ultrasonically welded together so that the frames 126 and 128 sandwich a peripheral edge 130 of the glass plate 122 therebetween. Details of the shelves 12-16 are provided below and in the copending U.S. patent application Serial No. 07/267,815 filed on Nov. 7, 1988.
The lower frame 128 includes a generally horizontally extending frame member 132 that extends beneath the periphery 130 of the glass plate 122 and a portion 134 of which, abuts the glass plate 122. A flange 136 extends upwardly from an outer surface of the frame member 132 a distance approximately equal to the thickness of the glass plate 122. A smaller flange 138 projects upwardly from the flange 136 for ultrasonically welding the lower frame 128 and the upper frame 126 together. As shown in FIG. 10, the lower frame 128 is formed with indentations 140, 142, 144 and 146 on the underside thereof. The indentations 140 and 144 cooperate with the stop 110 formed on the left single track support member 42; whereas, the indentations 142 and 146 cooperate with the stop 102 formed on the single track right support member 44 so that the refrigerator shelf 12 may not be inadvertently pulled out.
The upper frame 126 of the picture frame 124 includes a generally horizontally extending frame member 150 that extends above the periphery of the glass plate 122. A flange 152 extends downwardly from an inner surface of the frame member 150 so as to abut the upper surface 154 of the glass plate 122 about its entire periphery when the upper and lower frames 126 and 128 are secured together. The frame member 150 further includes a flange 156 that extends downwardly from an outer surface of the frame member 150. The flange 156 extends downwardly a sufficient distance such that the bottom surface 158 thereof is slightly above the bottom surface 160 of the frame member 132 of the lower frame 128 when the upper and lower frames 126 and 128 are secured together so that the lower frame 128 carries the load. A flange 162 extends downwardly from a mid portion of the frame member 150 at a distance from the flange 156 so as to accommodate the upwardly extending flange 136 of the lower frame 128. The flanges 156 and 162 aid in aligning the upper and lower frames 126 and 128 during the assembly of the refrigerator shelf.
The upper frame 126 further includes an integrally formed flange 164 that extends at a slight downward angle from the front of the picture frame 124. As shown in FIG. 10, the flange 164 has four sets of ribs 166, 168, 170 and 172 with a centrally disposed gripping area 174 so that the refrigerator shelf 12 may be easily pulled out. If desired, a decorative trim such as an aluminum strip 176 may be adhesively bonded to the front face of the flange 164. An integrally formed flange 178 further extends upwardly at a slight rearward angle from the rear of the upper frame 126. A reflector 180 such as an aluminum strip is secured to a front face of the flange 178 for decorative effect.
To ensure that a liquid spilled onto the glass plate 122 does not seep between the glass plate 122 and the upper frame 126, a silicon seal 182 is provided between the frame member 150 and the glass plate 122, abutting the flange 152. The silicon seal 182 may be in the form of a solid gasket extending about the entire periphery of the glass plate 122. Alternatively, the silicon seal 182 may be applied between the glass plate 122 and the upper frame 126 in liquid form.
When a left single track support member 42 and a right single track support member 44 are mounted at the same height on the liner sidewalls 26 and 30 of the refrigerator 10 as discussed above, a refrigerator shelf 12, 14-16 may be mounted in the refrigerator compartment 22 by sliding the refrigerator shelf 12, 14-16 into the tracks 97 and 109 formed in the right single track support member 44 and the left single track support member 42. More particularly, the refrigerator shelf 12, 14-16 is slid onto the support members 42 and 44 such that the left side 186 of the frame 124 of the refrigerator shelf 12 is positioned in the track 109 between the sidewall 54 and the upwardly extending projections 114-116 with the projections 114-116 abutting the edge surface 132a of the frame member 132 (FIG. 11) and the rib 120 abutting the flange 156. As shown in FIG. 10, a slot 187 is formed at the rear 188 of the lower frame 128 in the frame member 132, parallel to the left edge 190 of the lower frame 128 and at a distance from the edge 190 equal to the width of the frame member 132. Similarly, a slot 191 is formed in the flange 156 of the upper frame 126 at the rear thereof and spaced a distance from the left edge 193 of the upper frame 126 equal to the width of the flange 132 plus the width of the flange 156 so as to align the slot 191 with the slot 187 when the upper and lower frames are secured together. As the refrigerator shelf 12 is slid between the tracks of the left single track support member 42 and the right single track support member 44, the projections 114-116 slide through the slot 187 to permit the refrigerator shelf 12 to be mounted in the refrigerator compartment 22. The refrigerator shelf is held in place in the refrigerator compartment 22 by the stops 110 and 102 which respectively engage the indentations 144 and 146 formed on the lower frame 128 of the picture frame 124 of the refrigerator shelf 12. When mounted as such in the refrigerator compartment 22, the refrigerator shelf 12, 14-16 fits snugly in the left support member 42 while being able to move laterally in the track 97 of the right support member 44 so as to accommodate dimensional variations in the refrigerator compartment liner 24 and enable the shelf 12, 14-16 to be pulled out smoothly.
To pull the refrigerator shelf 12, 14-16 out, the refrigerator shelf 12, 14-16 is lifted slightly upwardly to disengage the stops 110 and 102 from the respective indentations 144 and 146. The shelf 12, 14-16 then is slid forward until the stops 110 and 102 engage the indentations 140 and 142. If it is desired to completely remove the shelf 12, the shelf is again lifted slightly upwardly and pulled forward so that the stops 110 and 102 disengage the indentations 140 and 142.
The double track support members 46 and 48 as shown in detail in FIGS. 12-14 support in upper tracks 50 and 51 a refrigerator shelf 13 having the same configuration as described above for the refrigerator shelf 12. Each of the double track support members 46 and 48 includes a lower track 52 and 53 to support a storage bin 20 therein. More particularly, the left double track support member 46 includes a sidewall 212 with an upper flange 204 extending the length thereof and a second flange 206 spaced from the upper flange 204 by a sufficient distance to accommodate the picture frame 124 of a refrigerator shelf 13 in the track 50. A stop 210 is formed on a front end of the second flange 206 so as to cooperate with the indentations 140 and 144 of the refrigerator shelf 13 as discussed above for the refrigerator shelf 12. The flange 206 further includes upwardly extending projections 214-216 extending from the outer edge of the flange 206. A small rib 220 extends outwardly from the sidewall 212 between the upper flange 204 and the second flange 206 so as to cooperate with the upwardly extending projections 214-216 to provide a snug fit for the left side 186 of the picture frame 124 of a refrigerator shelf 13 as discussed above for the left single track support member 42. A third flange 254 extends outwardly from the sidewall 212 of the double track support member 46, spaced below the second flange 206 so as to accommodate a front, curved gripping flange 205 that extends above the rim 256 of the storage bin 20. A lower flange 258 also extends outwardly from the sidewall 212 of the left double track support member 46 to form with the third flange 254 the lower track 52. The lower flange 258 has a downwardly curved lip 257 at its forward end so as to aid in mounting a storage bin 20 in the lower track 52. The lower flange 258 is also formed with upstanding projections 260-262 that extend upwardly from an outer edge of the flange 258. A horizontally extending lower track sidewall 259 parallels the sidewall 212 of the support member 46 but extends outwardly therefrom with a rib 259a extending the length of the lower track sidewall 259. The rib 259a and projections 260-262 provide a snug fit for the left side of the rim 256 of the storage bin 20 to substantially prevent lateral movement thereof. The lower flange 258 further includes an indentation 264 formed at a forward end 266 thereof. The indentation 264 cooperates with a stop 268 that extends downwardly from a downwardly extending flange 269 on the left side of the rim 265 formed on of the refrigerator bin 20. The stop 268 in cooperation with the indentation 264 prevents the refrigerator bin 20 from being inadvertently being pulled out of the lower track 52.
The right double track support member 48 includes an upper flange 194 that extends outwardly from a sidewall 200 of the right double track support member 48. A second flange 198 also extends outwardly from the sidewall 200, the second flange 198 being spaced from the top flange 194 so as to accommodate the right side 187 of the picture frame 124 of the refrigerator shelf 13 in the upper track 51. A third flange 272 extends outwardly from the sidewall 200 of the right double track support member 48 wherein the third flange 272 is spaced from the second flange 198 by a distance so as to accommodate the gripping flange 205 of the storage bin 20. A lower flange 274 is also formed, extending outwardly from the sidewall 200 of the right double track support member 48 and spaced a distance from the third flange 272 so as to accommodate the rim 256 of the storage bin 20. The lower flange 274 includes an indentation 276 that cooperates with a stop 278 formed on the right side of the storage bin 20 wherein the stop 278 extends downwardly from a downwardly extending flange 281 of the rim 256. The stop 278 and indentation 276 cooperate so as to prevent the storage bin from inadvertently being pulled out of the lower track 53 formed between the third flange 272 and the lower flange 274.
Each of the left double track support members 46 and the right double track support members 48 includes in a backside of the respective sidewalls 200 and 212 of the supporting members 48 and 46 a rearward slot 60 and a forward slot 58 such as shown in FIGS. 2 and 3 for the left single track support member 42. The slots enable the double track support members 46 and 48 to be mounted on a pair of horizontally aligned studs 88 and 90 on the sidewall 26, 30 of the liner 24 in the same manner as discussed above for the left single track support member 42.
Once the double track support members 46 and 48 are mounted on the respective left sidewall 26 and the right sidewall 30 of the liner 24 of the refrigerator compartment 22, a refrigerator shelf 13 and a storage bin 20 may be mounted therein. The refrigerator shelf 13 is slid between the upper flange 204 and the second flange 206 in the track 50 of the left double track support member 46 and the upper flange 194 and the second flange 198 in the track 51 of the right double track support member 48 in the same manner as discussed above with respect to the refrigerator shelf 12, 14-16 and the single track support members 42 and 44. A storage bin 20 is slid in the lower tracks 52 and 53 of the left and right double track support members 46 and 48 until the stops 278 and 268 seat in the respective indentations 276 and 264 of the respective right and left double track support members 48 and 46. When mounted in the lower tracks 52 and 53 of the support members 46 and 48, the left side of the storage bin rim 256 fits snugly in the support member 46 between the rib 257 and the projections 260-262 whereas the right side of the storage bin is free to move laterally within the track 53 of the support member 48 so as to accommodate dimensional variations in the refrigerator compartment liner 24.
As shown in FIGS. 1 and 18, a wine rack 18 may be mounted in the refrigerator compartment 22 on a pair of studs including a forward stud such as the stud 90 and a rearward stud such as the stud 88. The wine rack 18 includes an elongated bottle support member 290 having a U-shaped cross-section wherein the left side of the bottle support member 290 extends upwardly into an elongated side flange 292. The backside 294 of the side flange 292 of the wine rack 18 includes a rearward slot 296 formed at the rear end of the side flange 292 and further includes a forwardly positioned slot 298 formed at the front end of the flange 292. The rearward slot 296 opens towards the rear 300 of the flange 294 whereas the forwardly positioned slot 298 opens towards the bottom 302 of the flange 294 so that the wine rack 18 may be mounted on a pair of studs 88 and 90 as described for the left single track support member with reference to FIGS. 2 and 3.
Many modifications and variations of the present invention are possible in light of the above teachings. Thus, it is to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as described hereinabove. | A mounting system for an article supporting member in a refrigerator includes first and second support members each of which is removably secured to a respective pair of studs mounted on opposite sidewalls of the liner of a refrigerator compartment so that the height of the support members masy be adjusted. Each of the first and second support members includes a track for receiving opposite sides of a refrigerator shelf or storage bin for slidable movement therein. The track of the first support member permits lateral movement of the refrigerator shelf; whereas the track of the second support member substantially prevents lateral movement of the refrigerator shelf to accommodate dimensional variations in the liner of the refrigerator compartment. Each of the studs is a dovetail stud having a rounded upper and lower edge so as to permit a support member to be pivoted about one stud when mounting the support member to the refrigerator compartment liner. Each support member may have a single track or double tracks wherein the double tracks receive both a refrigerator shelf and a storage bin. Further, a wine rack may be mounted on a pair of studs in the same manner as a support member. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority from U.S. Provisional Application No. 60/066,643, filed Nov. 18, 1997, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to communication systems, and particularly to systems and methods for generating and transmitting data signals to the surface of the earth while drilling a borehole, wherein the transmitted signal is maximized and the probability of the system being jammed by drilling fluid particulates is minimized.
2. Description of the Related Art
It is desirable to measure or “log”, as a function of depth, various properties of earth formations penetrated by a borehole while the borehole is being drilled, rather than after completion of the drilling operation. It is also desirable to measure various drilling and borehole parameters while the borehole is being drilled. These technologies are known as logging-while-drilling and measurement-while-drilling, respectively, and will hereafter be referred to collectively as “MWD”. Measurements are generally taken with a variety of sensors mounted within a drill collar above, but preferably close, to a drill bit which terminates a drill string. Sensor responses, which are indicative of the formation properties of interest or borehole conditions or drilling parameters, are then transmitted to the surface of the earth for recording and analysis.
Various systems have been used in the prior art to transmit sensor response data from downhole drill string instrumentation to the surface while drilling a borehole. These systems include the use of electrical conductors extending through the drill string, and acoustic signals that are transmitted through the drill string. The former technique requires expensive and often unreliable electrical connections that must be made at every pipe joint connection in the drill string. The latter technique is rendered ineffective under most conditions by “noise” generated by the actual drilling operation.
The most common technique used for transmitting MWD data utilizes drilling fluid as a transmission medium for acoustic waves modulated downhole to represent sensor response data. The modulated acoustic waves are subsequently sensed and decoded at the surface of the earth. The drilling fluid or “mud” is typically pumped downward through the drill string, exits at the drill bit, and returns to the surface through the drill string-borehole annulus. The drilling fluid cools and lubricates the drill bit, provides a medium for removing drill bit cuttings to the surface, and provides a hydrostatic pressure head to balance fluid pressures within formations penetrated by the drill bit.
Drilling fluid data transmission systems are typically classified as one of two species depending upon the type of pressure pulse generator used, although “hybrid” systems have been disclosed. The first species uses a valving system to generate a series of either positive or negative, and essentially discrete, pressure pulses which are digital representations of transmitted data. The second species, an example of which is disclosed in U.S. Pat. No. 3,309,656, comprises a rotary valve or “mud siren” pressure pulse generator which repeatedly interrupts the flow of the drilling fluid, and thus causes varying pressure waves to be generated in the drilling fluid at a carrier frequency that is proportional to the rate of interruption. Downhole sensor response data is transmitted to the surface of the earth by modulating the acoustic carrier frequency.
U.S. Pat. No. 5,182,730 discloses a first species of data transmission system which uses the bits of a digital signal from a downhole sensor to control the opening and closing of a restrictive valve in the path of the mud flow. Such a transmission may reduce interference from drilling fluid circulation pump or pumps, and interference from other drilling related noises. The data transmission rate of such a system is, however, relatively slow as is well known in the art.
U.S. Pat. No. 4,847,815, which is incorporated herein by reference, discloses an additional example of the second species of data transmission system comprising a downhole rotary valve or mud siren. The data transmission rate of this system is relatively high, but it is susceptible to extraneous noise such as noise from the drilling fluid circulation pump. Additionally, for low flows, deep wells, small diameter drill strings, and/or high viscosity muds, this system requires small gap settings for maximizing signal pressure at the modulator. Under these conditions the system is susceptible to plugging or “jamming” by solid particulate material in the drilling mud, such as lost circulation material “LCM”, which will be subsequently defined.
U.S. Pat. No. 5,375,098, also incorporated herein by reference, discloses an improved rotary valve system which includes apparatus and methods for suppressing noise. Although data transmission rates are relatively high and relatively free of noise distortion, this rotary valve system is still susceptible to jamming by solid particulates at small gap settings.
The effects of the above parameters are shown by the signal strength relationship from Lamb, H., Hydrodynamics, Dover, New York, N.Y. (1945), pages 652-653, which is:
S=S o exp[−4π F ( D/d ) 2 (μ/K)]
where
S=signal strength at a surface transducer;
S o =signal strength at the downhole modulator;
F=carrier frequency of the MWD signal expressed in Hertz;
D=measured depth between the surface transducer and the downhole modulator;
d=inside diameter of the drill pipe (same units as measured depth);
μ=plastic viscosity of the drilling fluid; and
K=bulk modulus of the volume of mud above the modulator,
and by the modulator signal pressure relationship
S o ∝(ρ mud ×Q 2 )/A 2
where
S o =signal strength at the downhole modulator;
ρ mud =density of the drilling fluid;
Q=volume flow rate of the drilling fluid; and
A=the flow area with the modulator in the “closed” position, a function of the gap setting.
U.S. Pat. No. 5,583,827 discloses a rotary valve telemetry system which generates a carrier signal of constant frequency, and sensor data are transmitted to the surface by modulating the amplitude rather than the frequency of the carrier signal. Amplitude modulation is accomplished by varying the spacing or “gap” between a rotor and stator component of the valve. Gap variation is accomplished by a system which induces relative axial movement between rotor and stator depending upon the digitized output of a downhole sensor. The '827 patent also discloses the use of a plurality of such valve systems operated in tandem. The system is, however, mechanically and operationally complex, and is also subject to the same jamming limitations as previously discussed when operating at the small gap positions necessary for generating maximum signal amplitude.
All drill string components, including MWD tools, should be designed to allow the continuous flow of solids and additives suspended in the drilling fluid. As discussed previously, an important example of an additive is lost circulation material or “LCM”. One type of common LCM is “medium nut plug” which is a material used to control lost circulation of drilling fluids into certain types of formations penetrated by the drill bit during the drilling operation. This material can be of vital importance in drilling a well when it is used to plug fractures in formations, to isolate incompetent formations to which drilling fluid can be lost, or when drilling parameters result in too much overbalance pressure in the wellbore annulus with respect to the formation pressure. If loss of the drilling fluid occurs, the hydrostatic balance of the well may be disrupted and containment of the subsurface formation pressure may be lost. This has extreme negative safety implications for a rig and crew since loss of well control can lead to a “kick” and possibly a “blow-out” of the well. In view of these drilling mechanics and safety aspects, LCM such as medium nut plug is required in some drilling operations. Drilling equipment, including MWD equipment, must be able to pass LCM. As a result, the passage of medium nut plug is also a commonly accepted standard by which particulate performance of MWD tools is measured.
If jamming and plugging of the drill string occurs during flow of LCM in controlling lost circulation, the drill string must be removed from the well. This is a costly and complex operation, especially if the well and the downhole pressures are not stable. It is vital, therefore, to maintain the ability to transport LCM downhole via the drill string to arrest lost circulation problems in the well. LCM must, therefore, pass through all elements of the drill string, including the pressure pulse generator of a MWD tool.
Prior art rotary valve type pressure pulse modulators have used a lateral gap between the stator and rotor of the modulator to provide a flow area for drilling fluid, even when the modulator is in the “closed” position. As a result, the modulator is never completely closed as the drilling fluid must maintain a continuous flow for satisfactory drilling operations to be conducted. Thus, drilling fluid and particulate additives or debris must pass through the lateral gap of the modulator when it is in the closed position. In the prior art designs, the lateral gap has been limited to certain minimum values. At lateral gap settings below the minimum value, performance of the data telemetry system is degraded with respect to LCM tolerance such that jamming or plugging of the drill string may occur. Conversely, it is required that the lateral gap and associated closed flow area be as small as practical in order to maximize telemetry signal strength, which is proportional to the difference in differential pressure across the modulator when the modulator in the fully “open” and fully “closed” positions. Signal strength must be maximized at the MWD tool in order to maintain signal strength at the surface when low drilling fluid flow rates, increased well depths, smaller drill string cross sections, and/or high mud viscosity are mandated by the geological objective and particular drilling environment encountered. If the gap is reduced to less than the size of any particulate additives, there is increased difficulty in transporting these additives or debris through the modulator. At a certain point, depending upon the setting of the lateral gap between the rotor and the stator, the particle size and concentration, particle accumulation, packing and plugging of the drill string can occur. Additionally, at lower modulator frequencies, the amount of accumulation will be greater since the modulator is in the “closed” position for a longer period of time. Differential pressure will force the particles into the gap where they may wedge and jam the modulator. When this happens, the modulator rotor may malfunction, jam in the closed position, and the drill string may be packed off and plugged upstream from the modulator.
SUMMARY OF THE INVENTION
In view of the foregoing discussion of prior art, an object of this invention is to provide a pressure pulse generator, otherwise known as a modulator, with a high signal strength while allowing the free passage of drilling fluid particulates, such as LCM or debris, and thereby resisting jamming or plugging.
Another object of the invention is to provide a pressure pulse modulator which exhibits jamming or plugging resistance under a wide range of drilling fluid flow conditions, tubular geometries, well depths, and drilling fluid theological properties.
Yet another object of the invention is to provide a pressure pulse modulator which provides high signal strength with jam free operation under a wide range of drilling fluid flow conditions, tubular geometries, well depths, and drilling fluid theological properties.
Another objective of the invention is to provide a pressure pulse modulator which meets the above stated signal strength and operational characteristics, and still produces a suitable data transmission rate.
Still another objective of the invention is to provide a pressure pulse modulator which meets the above stated signal strength, data transmission rate and operational characteristics with an efficient use of available downhole power to operate the modulator.
Additional objects, advantages and applications of the invention will become apparent to those skilled in the art in the following detailed description of the invention and appended figures.
In accordance with the objects of the invention, a MWD modulator is provided and generally comprises a stator, a rotor which rotates with respect to the stator, and a “closed” flow opening area which is configured to reduce jamming, and which is reduced in area to maintain a desired signal strength. It has been found that the closed flow area “A” determines, for given drilling and borehole conditions, the signal strength, but the aspect ratio of the closed flow area A determines the opening's tendency to jam with particulates transported within the drilling fluid. The aspect ratio of the closed flow area A is defined as the ratio of the maximum dimension of the opening divided by the minimum dimension of the opening. As an example, assume that one closed flow passage of area A has a high aspect ratio due to a relatively large maximum dimension (such as a long rotor blade) and a relatively small minimum dimension (such as a narrow rotor-stator gap). Assume that a second closed flow passage of the same area A has a lower aspect ratio, which would be a passage in the form of a circle, a square, or some other shape. The signal pressure amplitude would be the same for both, since the areas A are equal. The closed flow opening with the smaller aspect ratio will exhibit less of a tendency to trap particulates, assuming that the minimum principal dimension is greater than the particle size. For the opening with the long and narrow area, the narrow or minimum principal dimension (i.e. the gap setting) is sometimes required to be less than the size of particular additives, such as medium nut plug LCM, in order to obtain usable telemetry signal strength under certain conditions of flow rate, well depth, telemetry frequency, drilling fluid weight, drilling fluid viscosity and drill string size. This can result in jamming of the modulator and subsequent plugging of the drill string.
The rotor and stator of the present modulator are configured so that the area A of the fluid flow path with the modulator in the “closed” position is sufficiently small to obtain the desired signal strength, but also configured with a low aspect ratio and sufficient minimum principal dimension to prevent particulate accumulation, jamming, and plugging. Several shapes including circular, triangular, rectangular, and annular sector openings are disclosed. Because of the improved closed flow path geometry, the gap between the modulator rotor and stator can be reduced to sufficiently tight clearances to further increase signal strength and also to exclude particulates such that jamming between rotor blades and stator lobes does not occur. The particles are instead swept or scraped by interaction of the rotor blades with the stator lobes during rotation into the “open” position of the modulator orifices and are carried away by the drilling fluid. When the rotor blade lateral faces bring particles against stator lateral faces, shearing of particles by the rotor can occur. This shearing is assisted by a magnetic positioner torque which is part of the system described in U.S. Pat. No. 5,237,540, which is incorporated herein by reference. The power required to operate the modulator in this configuration under high concentrations of particulate additives is significantly reduced as compared to prior art modulators. The rotor/stator arrangement of the present invention is somewhat analogous to a set of sharp, tight fitting scissors, while prior art modulators with large rotor/stator gaps are likewise analogous to dull, loose fitting scissors. The former cuts and shears with minimum effort, while the latter cuts poorly and jams.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features, advantages and objects of the present invention are attained can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 illustrates the present invention embodied in a typical drilling apparatus;
FIG. 2 a is an axial sectional view of a pressure modulation device comprising a stator and rotor;
FIG. 2 b is a view of a prior art stator and rotor assembly in a fully open position;
FIG. 2 c is a view of the prior art stator and rotor assembly in a fully closed position;
FIG. 3 is a lateral sectional view of the prior art rotor blade and stator body and flow orifice;
FIG. 4 a is a view of a first alternate embodiment of a stator and rotor assembly of the present invention in a fully open position;
FIG. 4 b is a view of the first alternate embodiment of the stator and rotor assembly of the present invention in a fully closed position;
FIG. 4 c is a lateral sectional view of the rotor blade and stator body and flow orifice of the present invention in the first alternate embodiment;
FIG. 4 d is a sectional view of a labyrinth seal between the stator and a rotor blade.
FIG. 5 a is a view of a second alternate embodiment of a stator and rotor assembly of the present invention in a fully open position, wherein each rotor blade comprises a flow opening;
FIG. 5 b is a view of the second alternate embodiment of the stator and rotor assembly of the present invention in a fully closed position;
FIG. 5 c is a lateral sectional view of a rotor blade and stator body and flow orifice of the present invention in the second alternate embodiment;
FIG. 6 a is a view of a third alternate embodiment of a stator and rotor assembly of the present invention in a fully open position, wherein each stator flow orifice comprises flow indentations;
FIG. 6 b is a view of the third alternate embodiment of the stator and rotor assembly of the present invention in a fully closed position;
FIG. 6 c is a lateral sectional view of a rotor blade and stator body and flow orifice of the present invention in the third alternate embodiment;
FIG. 7 shows the relationships between rotor position, differential pressure across the modulator device, and fluid flow area for the embodiments of the invention illustrated in the first, second and third alternate embodiments of the invention;
FIG. 8 a illustrates a preferred embodiment of the stator and rotor assembly of the present invention in a fully open position;
FIG. 8 b illustrates the preferred embodiment of the invention with the stator and rotor assembly in a fully closed position;
FIG. 8 c is a lateral sectional view of the rotor and stator assembly of the preferred embodiment of the invention in the fully closed position;
FIG. 9 a is a view of the stator and rotor assembly of the preferred embodiment of the invention at the beginning of a time period in which the assembly is in the fully closed position;
FIG. 9 b is a view of the stator and rotor assembly of the preferred embodiment of the invention at the end of the time period in which the assembly is in the fully closed position;
FIG. 9 c is a view of the stator and rotor assembly of the preferred embodiment of the invention in transition between the fully open position and the fully closed position; and
FIG. 10 shows the relationships between rotor position, differential pressure across the modulator device, and fluid flow area for the preferred embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates the present invention incorporated into a typical drilling operation. A drill string 18 is suspended at an upper end by a kelly 39 and conventional draw works (not shown), and terminated at a lower end by a drill bit 12 . The drill string 18 and drill bit 12 are rotated by suitable motor means (not shown) thereby drilling a borehole 30 into earth formation 32 . Drilling fluid or drilling “mud” 10 is drawn from a storage container or “mud pit” 24 through a line 11 by the action of one or more mud pumps 14 . The drilling fluid 10 is pumped into the upper end of the hollow drill string 18 through a connecting mud line 16 . Drilling fluid flows under pressure from the pump 14 downward through the drill string 18 , exits the drill string 18 through openings in the drill bit 12 , and returns to the surface of the earth by way of the annulus 22 formed by the wall of the borehole 30 and the outer diameter of the drill string 18 . Once at the surface, the drilling fluid 10 returns to the mud pit 24 through a return flow line 17 . Drill bit cuttings are typically removed from the returned drilling fluid by means of a “shale shaker” (not shown) in the return flow line 17 . The flow path of the drilling fluid 10 is illustrated by arrows 20 .
Still referring to FIG. 1, a MWD subsection 34 consisting of measurement sensors and associated control instrumentation is mounted preferably in a drill collar near the drill bit 12 . The sensors respond to properties of the earth formation 32 penetrated by the drill bit 12 , such as formation density, porosity and resistivity. In addition, the sensors can respond to drilling and borehole parameters such as borehole temperature and pressure, bit direction and the like. It should be understood that the subsection 34 provides a conduit through which the drilling fluid 10 can readily flow. A pulse signal device or modulator 36 is positioned preferably in close proximity to the MWD sensor subsection 34 . The pulse signal device 36 converts the response of sensors in the subsection 34 into corresponding pressure pulses within the drilling fluid column inside the drill string 18 . These pressure pulses are sensed by a pressure transducer 38 at the surface 19 of the earth. The response of the pressure transducer 38 is transformed by a processor 40 into the desired response of the one or more downhole sensors within the MWD sensor subsection 34 . The direction of propagation of pressure pulses is illustrated conceptually by arrows 23 . Downhole sensor responses are, therefore, telemetered to the surface of the earth for decoding, recording and interpretation by means of pressure pulses induced within the drilling fluid column inside the drill string 18 .
As described previously, pulse signal devices are typically classified as one of two species depending upon the type of pressure pulse generator used. The first species uses a valving system to generate a series of either positive or negative, and essentially discrete, pressure pulses which are digital representations of the transmitted data. The second species comprises a rotary valve or “mud siren” pressure pulse generator, which repeatedly restricts the flow of the drilling fluid, and causes varying pressure waves to be generated in the drilling fluid at a frequency that is proportional to the rate of interruption. Downhole sensor response data is transmitted to the surface of the earth by modulating the acoustic carrier frequency. The pulse signal device 36 of the present invention is of the second species.
FIG. 2 a is an axial sectional view of the major components of a rotary valve or mud siren type pulse signal device. The pulse signal device 36 comprises a bladed rotor 44 which turns on a shaft 42 and bearing assembly 46 . Drilling fluid, again indicated by the flow arrows 20 , enters a stator comprising a stator body 52 and preferably a plurality of stator orifices 54 . The drilling fluid flow through the stator-rotor assembly of the pulse signal device 36 is restricted by the rotation of the rotor as is better seen in FIGS. 2 b and 2 c.
FIG. 2 b is a view of the rotor 44 and stator orifices 54 and stator body 52 as seen in a plane perpendicular to the shaft 42 . FIG. 2 b depicts a prior art stator-rotor assembly, where the relative positions of the rotor blades and stator orifices are such that the restriction of drilling fluid flow through the assembly is at a minimum. This is referred to as the “open” position. FIG. 2 c shows the same perspective view of the prior art stator-rotor assembly as FIG. 2 b, but with the relative positions of the rotor blades and the stator orifices such that the restriction of the drilling fluid flow through the assembly is at a maximum. This is referred to as the “closed” position.
Drilling fluid flow through the stator-rotor assembly is not terminated when the assembly is in the closed position. This is because of a finite separation or “gap” 50 between the rotor and stator, as best seen in FIG. 2 a. As a result, the pulse signal device 36 is never completely closed since the drilling fluid 10 must maintain a continuous flow for satisfactory drilling operations to be conducted. Thus, drilling fluid 10 and any particulate additives or debris suspended within the drilling fluid must pass through the gap 50 when the pulse signal device 36 is in the closed position. In the prior art, the gap 50 has been limited to certain minimum values. At gap settings below these minimum values, the pulse signal device 36 tends to jam or plug with particles 56 in the drilling fluid as illustrated in FIG. 3 More specifically, when the rotor blade 44 aligns with the stator orifice 54 as shown in FIG. 3, the particles 56 tend to jam in the gap 50 . Arrow 45 illustrates the direction of rotor blade movement with respect to the stator. Jamming at the stator-rotor assembly of the pulse signal device 36 can cause plugging of the entire drill string 18 . From a jamming and plugging perspective, it is therefore desirable to make the gap 50 as large as possible. From a telemetry signal strength aspect, it is desirable to set the gap 50 as small as possible so that the associated flow area is minimized when the pulse signal device 36 is in the closed position. Minimum “closed” flow area maximizes the telemetry signal strength, which is proportional to the pressure differential between the modulator in the fully “open” and fully “closed” positions. Signal strength must be maximized at the MWD subsection 34 in order to maintain signal strength at the pressure transducer 38 at the surface when low drilling fluid flow rates, increased well depths, small drill string cross sections, and/or high mud viscosity are mandated by the geological objective and the particular drilling environment encountered. Stated mathematically,
S o ∝(ρ mud ×Q 2 )/A 2
where
S o =signal strength at the downhole modulator;
ρmud=density of the drilling fluid;
Q=volume flow rate of the drilling fluid; and
A=the flow area with the modulator in the “closed” position, a function of the gap setting.
The signal strength at the surface, S, using the previously referenced work of Lamb, is expressed as
S=S o exp[−4π F ( D/d ) 2 (μ/K)]
where
S=signal strength at a surface transducer;
S o =signal strength at the downhole modulator;
F=carrier frequency of the MWD signal expressed in Hertz;
D=measured depth between the surface transducer and the downhole modulator;
d=inside diameter of the drill pipe (same units as measured depth);
μ=plastic viscosity of the drilling fluid; and
K=bulk modulus of the volume of mud above the modulator. If the gap 50 is reduced to less than the size of the particulate additive particles 56 , there is increased difficulty in transporting these additives or debris through the modulator. At a certain point, depending upon the setting of the gap 50 between the rotor blades 44 and the stator body 52 , the particle size, and the particle concentration, packing and plugging of the drill string 18 can occur. Additionally, at lower modulator frequencies, the amount of accumulation will be greater since the modulator is in the “closed” position for a longer period of time. Differential pressure will force the particles 56 into the gap 50 where they may wedge and jam the modulator, especially in the case of LCM which, by design, is intended to seal and create a pressure barrier. When this happens, the modulator rotor 44 may malfunction and jam in the closed position, and the drill string 18 may be packed off and plugged upstream from the pulse signal device 36 .
It has been found that the closed flow area A determines, for given conditions, the signal strength, but the aspect ratio and the minimum principal dimension of the closed flow area A determines the opening's tendency to jam with particulates transported within the drilling fluid. The aspect ratio of the closed flow area A is defined as the ratio of the maximum dimension of the opening divided by the minimum dimension of the opening. As an example, assume that one closed flow passage of area A has a high aspect ratio due to a relatively large maximum dimension such as the blades of the rotor 44 with a relatively long radial extent 51 ′ (see FIG. 2 b ), and a relatively small minimum dimension such as a narrow gap 50 . This is typical of the prior art devices illustrated in FIGS. 2 b, 2 c and 3 . These prior art devices tend to jam as illustrated in FIG. 3 .
The present invention employs a labyrinth “seal” between the rotor and the stator which defines a much smaller lateral gap between these two components. In addition, the present invention also employs a closed flow passage with typically the same closed flow area A as prior art devices, but with a closed flow area that has a smaller aspect ratio and a minimum principal dimension greater than the anticipated maximum particle size. The invention retains signal strength, yet resists jamming with particulate matter.
A preferred and three alternate embodiments of the invention are disclosed, with the alternate embodiments being presented first. It should be emphasized that the alternate embodiments of the invention, as well as the preferred embodiment, employ apparatus and methods to obtain closed flow openings with low aspect ratios and minimum principal dimensions to prevent signal device jamming, and with closed flow areas sufficiently small to obtain the desired signal telemetry strength.
Alternate Embodiments
FIG. 4 a is a view of a rotor 64 and stator assembly of a first alternate embodiment of the invention, as seen perpendicular to the shaft 42 , in the open position. FIG. 4 b depicts the same perspective view of the rotor-stator assembly of the first alternate embodiment in the closed position. Rotor blades 64 and the stator orifices 74 are configured such that the closed flow areas, identified by the numeral 60 , form approximately equilateral triangles with small aspect ratios. As shown in FIG. 4 d, the rotor blades 64 overlap the stator body 52 to form a labyrinth seal identified by the numeral 51 and defining an axial gap 50 ′. The low aspect ratio of the cumulative closed flow area with a minimum principal dimension greater than the anticipated maximum particle size prevents jamming. This is seen in the axial view of FIG. 4 c, wherein the axial gap 50 ′ defined by the labyrinth seal 51 is substantially reduced, while the rotor blade and stator orifice design allows drilling fluid and suspended particles 56 to flow through the closed flow area as illustrated by the arrows 20 . Even with this enhanced jamming performance, the cumulative magnitude A of the closed flow path remains relatively small, thereby maintaining the desired signal strength. Once again, the arrow 45 illustrates the direction of rotor blade movement with respect to the stator in the first alternate embodiment of the invention.
FIG. 5 a is a view of a rotor 75 and stator assembly of a second alternate embodiment of the invention, as seen perpendicular to the shaft 42 , in the open position. The stator orifices 54 and body 52 are, for purposes of discussion, the same as those illustrated in FIGS. 2 b, 2 c, and 3 . The rotor blades 75 contain preferably circular flow passages 70 which have an aspect ratio of 1.0 and principal dimension (diameter) greater than the maximum anticipated particle size. FIG. 5 b illustrates the second alternate stator-rotor assembly in the closed position. The rotor blades 75 and the stator orifices 54 are aligned such that drilling fluid and suspended particles 56 can pass through the circular flow passages 70 with reduced probability of jamming since the aspect ratio of each opening is low with sufficient minimum principal dimension (diameter) to allow passage of particulate matter. Again, for purposes of discussion, assume that the sum of the areas of the flow passages 70 is equal to A. Also, the labyrinth seal 51 as described above is again present. The second alternate embodiment is shown in the axial view of FIG. 5 c, wherein the gap 50 ′ again is substantially reduced to only allow movement between the rotor and stator, while the rotor blade and stator orifice design allows drilling fluid 10 containing suspended particles 56 to flow through the closed flow path as illustrated by the arrows 20 . Even with the enhanced jamming performance due to the closed flow area with a small aspect ratio and sufficient minimum principal dimension to allow passage of particulate matter, the magnitude of the flow area remains relatively small, thereby maintaining the desired signal strength. Again, the arrow 45 illustrates the direction of rotor blade movement with respect to the stator.
FIGS. 6 a - 6 c illustrate yet a third alternate embodiment of the invention. FIG. 6 a is a view of a rotor and stator assembly, as seen perpendicular to the shaft 42 , in the open position. The rotor 44 is, for purposes of discussion, identical to the rotor design shown in FIGS. 2 b and 2 c. The stator body 82 , however, contains recesses 80 on each side of the stator orifices 84 as shown in FIG. 6 b, which also illustrates the stator-rotor assembly in the closed position. Again, the previously described labyrinth seal 51 is present. The rotor blades 44 and the stator orifices 84 are aligned in the closed position so that drilling fluid and suspended particles 56 can pass through the recesses 80 as shown in FIG. 6 c. The flow area in this closed position is configured approximately as a square thereby minimizing the aspect ratio. The gap 50 ′ is again set to a minimum value which permits free movement between the rotor and stator. Again, the arrow 45 illustrates the direction of rotor blade movement with respect to the stator. Particle jamming is again prevented with this third alternate embodiment of the invention since the aspect ratio of the closed flow path through the recesses 80 is small with sufficient minimum principal dimension to allow passage of particulate matter. It is again assumed for purposes of discussion that the sum of the areas of the flow passages through the recesses 80 is equal to A. This third alternate embodiment of the invention also allows drilling fluid 10 containing suspended particles 56 to flow through the closed flow area A as illustrated by the arrows 20 with reduced likelihood of jamming. The magnitude A of the area once again remains relatively small thereby maintaining the desired signal strength.
Preferred Embodiment
FIGS. 8 a - 8 c illustrate the preferred embodiment of the invention. Similar operational principles as previously detailed also apply to this preferred embodiment. FIG. 8 a is a view of a rotor 144 and stator assembly, as seen perpendicular to the shaft 42 . The radius of each blade of the rotor 144 is defined as r 1 and is measured from the center line axis of the shaft 42 to the outer perimeter of the rotor. The position of the rotor 144 with respect to stator orifices 154 within the body 152 is such that the orifices are completely open. The radius of each stator orifice 154 is defined as r 2 and is measured from the center line axis of the shaft 42 to the outer perimeter of the orifice. FIG. 8 b illustrates the rotor-stator assembly in the fully closed position, leaving closed flow orifices 170 through which drilling fluid and suspended particles can flow. Labyrinth seals 51 are again employed between the rotor 144 and the stator body 152 . The closed flow orifice, or minimum principal dimension, is therefore defined by the difference in radii r 1 and r 2 . FIG. 8 c is a lateral sectional view A-A′ of FIG. 8 b, and more clearly shows the movement of suspended particles 156 through the closed flow orifices 170 . In this preferred embodiment, the area of the closed flow orifices 170 remains constant for a certain period of time to extend the duration of the pressure pulse to impart more energy to the pressure signal. This additional energy further helps in the transmission of the pressure signal to the surface. Additionally, the pulse shape more closely approximates a sinusoid, the advantages of which have been detailed in U.S. Pat. No. 4,847,815. In the '815 patent, the modulator signal starts to deviate from the sinusoid as the lateral gap between rotor and stator is reduced for higher signal amplitudes.
Features of the preferred embodiment of the invention are further illustrated in FIGS. 9 a, 9 b, and 9 c. FIG. 9 a shows the position of the rotor 144 at the start of the closed position, and FIG. 9 b shows the position of the rotor 144 at a later time at the end of the closed position. It is apparent that the areas of the closed flow orifices 170 remain constant during the period of time extending from the start of the closed position (FIG. 9 a ) to the end of the closed position (FIG. 9 b ). FIG. 9 c is a view of the rotor and stator assembly of the preferred embodiment of the invention in transition between the fully open position (FIG. 8 a ) and the fully closed position (FIGS. 9 a and 9 b ). In the preferred embodiment, the pulse shape and duration is controlled by the amount of angular rotation of the rotor 144 where the area of the closed flow orifices 170 remains constant or, alternately stated, “dwells” in the closed position. This results in a pulse shape, as will be discussed in a subsequent section, which is substantially different from the pulse shapes produced by other embodiments of the invention. Otherwise, the aspect ratio of the closed flow area along with the minimum principal dimension allows passage of normal mud particles 156 and additives such as medium nutplug LCM as described in other embodiments of the invention. Other features described in other embodiments are also applicable to the preferred embodiment.
Performance
As previously discussed, the present pulsed signal device repeatedly restricts the drilling fluid flow causing a varying pressure wave to be generated in the drilling fluid with a frequency proportional to the rate of restriction. Downhole sensor data are then transmitted through the drilling fluid within the drill string by modulating this acoustic character.
FIG. 7 shows the relationship 90 between modulator rotor position and differential pressure across the modulator and the relationship 92 between rotor position and flow area for all embodiments of the invention except the preferred embodiment. The rotor-stator assembly comprises three rotor blades spaced on 120 degree centers and three stator orifices also spaced on 120 degree centers. The number of degrees of the rotor from the fully “open” position is plotted on the abscissa. The curve 90 represents differential pressure across the modulator on the left hand ordinate scale 94 . The curve 92 represents fluid flow area through the modulator on the right hand ordinate scale 96 . Since there are three rotor blades, the pressure modulator assembly will be fully “closed” at a value of 60 degrees from the fully “open” position. This is reflected in the peak 104 in the differential pressure curve 90 and the minimum 98 in the flow area curve 92 at 60 degrees from the open position. Conversely, at 0 degrees and 120 degrees from the open position, the differential pressure curve 90 exhibits minima 102 and the flow area curve 92 exhibits maxima 100 . The curve 90 representing differential pressure varies inversely with flow area squared as would be expected from the modulator signal pressure relationship previously discussed.
FIG. 10 shows the relationship 190 between modulator rotor position and differential pressure across the modulator for the preferred embodiment of the invention as shown in FIGS. 8 a - 8 c and FIGS. 9 a - 9 c. FIG. 10 also shows the relationship 192 between rotor position and flow area for the preferred embodiment. The rotor-stator assembly again comprises three rotor blades spaced on 120 degree centers and three stator orifices also spaced on 120 degree centers. The number of degrees of the rotor from the fully “open” position is again plotted on the abscissa. The curve 190 represents differential pressure across the modulator on the left hand ordinate 194 . The curve 192 represents fluid flow area through the modulator on the right hand ordinate 196 . The extended time period of the pressure pulse at a maximum differential pressure 204 is clearly shown and results, as previously discussed, from the rotor 144 which “dwells” with a closed flow area 198 for a corresponding time period. The differential pressure drops to a value identified by the numeral 202 when the rotor moves so that the flow area is maximized at a value identified by the numeral 200 .
In all embodiments of the invention set forth in this disclosure, a rotor comprising three blades and stators comprising three flow orifices have been illustrated. It should be understood, however, that the teachings of this disclosure are also applicable to stator-rotor assemblies comprising fewer or additional rotor blades and complementary stator flow orifices. As an example, the rotor can have “n” blades, where n is an integer. Each blade would then preferably centered around the rotor at spacings of 360/n degrees.
All illustrated embodiments illustrate either stator or rotor designs which yield the desired low closed flow aspect ratio and low closed flow area. It should be understood, however, that both stator and rotor can be constructed to obtain these design goals. As an example, the stator body can be fabricated with indentations in the flow orifices as shown in FIGS. 6 b and 6 c, and the rotor blades can be formed with notches which align with these indentations when the assembly is in a fully closed position.
It will be appreciated by those skilled in the art that there are yet other modifications that could be made to the disclosed invention without deviating from its spirit and scope as so claimed. | A system is disclosed for generating and transmitting data signals to the surface of the earth while drilling a borehole, the system operating by generating pressure pulses in the drilling fluid filling the drill string. The system is designed to maximize signal strength while minimizing the probability of jamming by drilling fluid particulates. The system uses a rotary valve modulator consisting of a stator with flow orifices through which drilling fluid flows, and a rotor which rotates with respect to the stator thereby opening and restricting flow through the orifices and thereby generating pressure pulses. The flow orifices with the stator in a “closed” position are configured to reduce jamming, and to simultaneously minimize flow area in order to maximize signal strength. This is accomplished by imparting a shear to the fluid flow through the modulator, and minimizing the aspect ratio and maximizing the minimum principal dimension of the closed flow area. A preferred embodiment and three alternate embodiments of the modulator are disclosed. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 10/310,692, filed Dec. 5, 2002, now U.S. Pat. No. 6,837,010, issued Jan. 4, 2005.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to connection apparatus for use with seismic braces. In particular, the present invention relates to connection apparatus which prevent seismic and gravitational loads on steel structural frames from being applied nonaxially to seismic braces. By way of example, the connection apparatus may allow the brace to pivot relative to a structural frame.
2. Background of Related Art
In many areas of the world, particularly seismically active areas, large buildings and other structures may be subjected to seismic loads. In order to prevent structures from being damaged by seismic loads, particularly the vibrations that follow the application of seismic loads to structures, or to at least reduce the amount of damage that seismic loading may cause to such structures, various shock-absorption devices have been developed.
One such shock absorption device, which is useful with steel structural frames, is commonly referred to as a “seismic brace.” As shown in FIG. 1 , a pair of seismic braces 10 is often arranged within each “bay” 32 of a steel structural frame 30 , each bay 32 typically being formed by an adjacent pair of substantially horizontally oriented steel beams 34 (e.g., beams 34 u , 34 L shown in FIG. 1 ) and an adjacent pair of substantially vertically oriented steel columns 36 . Bottom corners 38 of each bay 32 are formed at junctions between a lower substantially horizontally oriented steel beam 34 L and the substantially vertically oriented steel columns 36 at each side of bay 32 . Lower ends 12 L of seismic braces 10 are typically secured at opposite bottom corners 38 of bay 32 . Upper ends 12 u of seismic braces 10 are typically secured to an upper substantially horizontally oriented steel beam 34 u at adjacent, substantially central locations thereof. As such, the two seismic braces 10 within a bay 32 of steel structural frame 30 are arranged in an inverted “V” configuration. Other, similar arrangements of seismic braces are also known, including “V” configurations, alternative “V” and inverted “V” configurations, a single, diagonally oriented seismic brace 10 in each bay 32 and another, oppositely oriented seismic brace 10 in the next laterally adjacent bay 32 (i.e., such that seismic braces 10 in two adjacent bays 32 form a “V” or inverted “V”), and the like. By arranging seismic braces 10 in this manner, when a seismic, or earthquake, load is applied to the structure of which steel structural frame 30 is a part, typically by shearing bay 32 in the directions of arrows 40 and 42 , one seismic brace 10 a of a pair will be subjected to a compressive load, depicted by arrows 44 , while a tensile load, illustrated by arrows 46 , will be applied to the other seismic brace 10 b.
Conventionally, seismic braces have been rigidly secured to the beams 34 and/or columns 36 of steel structural frames 30 . FIGS. 2 through 2B illustrate an exemplary conventional connection, which includes the use of planar gusset plates 15 that are welded into place relative to a beam 34 and/or a column 36 and which have perpendicular extensions 16 welded to each side thereof. As shown in FIG. 2A , a cross-section taken perpendicular to the planes of both gusset plate 15 and extensions 16 thereof has a generally cruciform shape and, thus, four interior corners 17 . Thus, each gusset plate 15 is configured complementarily to the exposed end 12 of a yielding core 11 ( FIG. 1 ) of a seismic brace 10 ( FIG. 1 ), which also typically has a cross-section, taken transverse to the length thereof, that is generally cruciform in shape and, thus, includes four interior corners 13 that extend along the length thereof, as shown in FIG. 2B . The cross-section of an exposed end 12 of a yielding core 11 of a seismic brace 10 and the corresponding features of the cross-section taken through gusset plate 15 and extensions 16 thereof may have substantially the same dimensions. A rigid connection between these two elements is typically effected by way of intermediate securing elements 19 , which are typically referred to as “splice plates,” positionable across portions of both an exposed end 12 and a gusset plate 15 /extension 16 , within corresponding interior corners 13 and 17 . Each intermediate securing element 19 includes apertures 20 , 21 formed therethrough, which respectively align with corresponding apertures 14 formed through exposed ends 12 of yielding core 11 and apertures 18 formed through gusset plate 15 and extensions 16 therefrom. Apertures 14 , 18 , 20 , and 21 are typically configured to receive bolts 22 , which, along with complementarily threaded nuts 23 , secure intermediate securing elements 19 in place with respect to both gusset plates 15 and exposed ends 12 of yielding core 11 , thereby securing seismic braces 10 into place relative to steel structural frame 30 .
A seismic brace 10 ( FIG. 1 ) is secured to a steel structural frame 30 by aligning exposed ends 12 of a yielding core 11 ( FIG. 1 ) of each seismic brace 10 with a corresponding gusset plate 15 that has already been secured to one or more of a beam 34 and/or a column 36 of steel structural frame 30 , as well as with extensions 16 that have been secured to that gusset plate 15 . Intermediate securing elements 19 are then positioned within interior corners 13 and 17 , then bolted (e.g., with bolts 22 and complementarily threaded nuts 23 ) to gusset plate 15 , extensions 16 therefrom, and exposed end 12 . As shown, the connection of exposed ends 12 to gusset plate 15 is typically established by way of four intermediate securing elements 19 which have L-shaped cross-sections, taken transverse to the lengths thereof.
Referring again to FIG. 1 , in addition to applying loads axially to seismic braces as a result of the shear generated by seismic and gravitational loads, rigid connections of this type typically transfer additional shears and moments, which are generated as a seismic brace 10 drifts laterally. Application of shear and moment to a yielding core 11 of a seismic brace 10 along vectors which are not located in a plane of bay 32 undesirably causes a bending moment and shear stress to be applied to yielding core 11 , which, along with compressive loads applied thereto, results in a so-called “combined stress” that is greater on one side of yielding core 11 than on the other and that may cause seismic brace 10 to buckle in an unintended direction. When such buckling occurs, seismic brace 10 is no longer useful for either shock absorption or structural support.
Thus, a connection apparatus which substantially isolates a seismic brace from nonaxially oriented loads, as well as that reinforces or isolates the seismic brace from shears and moments that occur as a seismic brace drifts from a plane of a bay of a steel structural frame in which the seismic brace is located, would be an improvement over the existing art of which the inventors are aware.
SUMMARY OF THE INVENTION
A connection apparatus according to the present invention includes a first member, or frame-side member, which is configured to be secured to a structural frame, a second member, or brace-side member, which is configured to be secured to a core member of a seismic brace, and a coupling member. The frame-side member and brace-side member both include coupling elements which are configured to receive or to be received by complementary portions of the connection member.
In an exemplary embodiment, the frame-side member of the inventive connection apparatus may comprise a substantially planar gusset plate. The gusset plate of the frame-side member is configured to be welded into a corner formed at a junction between two structural steel frame members. The gusset plate includes an aperture, which is substantially circular in shape, formed therethrough. The brace-side member may include two knife plates which are spaced apart from one another a sufficient distance that the gusset plate may be interleaved therewith. Both elements of the brace-side member also include apertures, which are in alignment with one another and alignable with the aperture of the frame-side member. The apertures of the elements of the brace-side member may have substantially the same size and configuration (e.g., substantially circular) as the aperture of the frame-side member. Upon assembly of the frame-side and brace-side members with the apertures in substantial alignment, the coupling member, which may have a substantially cylindrical central section, may be introduced into the apertures and secured in place relative to the frame-side and brace-side members, thereby coupling the frame-side and brace-side members of the connection apparatus to one another.
The coupling member of the connection apparatus may be held in place by way of enlarged heads at the ends thereof, bent regions at the ends thereof, securing elements that extend through apertures near the ends thereof, transversely to the length of the coupling member (e.g., like cotter pins), or by other position-retaining means.
The knife plates of the brace-side member are secured in place relative to a load-bearing member, or “core,” of a seismic brace. For example, the knife plates may be welded directly to the core or to an intermediate member which is, in turn, welded to the core. These arrangements facilitate the positioning of an end of a yielding core closer to the structural steel frame than do conventional, rigid connections, which typically consume a significant portion of the fixed distance between brace connection locations. Thus, connection apparatus according to the present invention may facilitate the use of seismic braces which include yielding cores that are longer than the yielding cores of conventional seismic braces that may be used at the same location of a structural steel frame. As is well known in the art, an increase in the length of a yielding core means that the strain rate on the yielding core will be less, resulting in a fatigue life which is longer than the fatigue life of a similar brace secured at a similar location using conventional, rigid connection apparatus.
Additionally, a connection apparatus according to the present invention may include a collar with one or more members that extend over a junction between the brace-side member and the end of a seismic brace on which the connection apparatus is used. By way of example only, a first end of each member of a collar may be secured to one or both of a portion of the brace-side member (e.g., the knife plates or intermediate member) or to the core of a seismic brace with which the connection apparatus is used, while a second end of each collar member may be positioned adjacent to an external shell, or shell, sleeve, or tube exterior, or other exterior surface of the seismic brace. The collar may be permitted to slide longitudinally relative to the external sleeve as the yielding core is compressed and elongated. It is currently preferred that at least a portion of the collar member extend over and substantially parallel to an end portion of the external shell or other exterior surface of the seismic brace.
Such a connection apparatus may be used with a variety of types of compression and tension-type seismic braces, including those with single, somewhat planar yielding cores, as well as those with multiple cores. The collar of the connection apparatus may also be used with other types of connection apparatus, including known, rigid connection apparatus for seismic braces. The collar is particularly useful with seismic braces that include axial-load-bearing cores that are surrounded by buckling-limiting material encased by external sleeves.
In another embodiment, the frame-side member of a connection apparatus according to the present invention may include a pair of gusset plates, while the brace-side member of such a connection apparatus comprises an exposed end of a core of a seismic brace or an extension therefrom which is rigidly secured thereto. The gusset plates of the frame-side member are configured to be secured to a steel structural frame in spaced-apart relation to one another and oriented substantially parallel to each other, with an aperture formed through each gusset plate being in substantial alignment with an aperture of the other gusset plate. The brace-side member is configured to be positioned between the gusset plates such that an aperture thereof substantially aligns with the substantially aligned apertures of the gusset plates. Upon arranging and assembling the frame-side and brace-side members in this manner, a coupling member, such as an elongate member with a substantially cylindrical center section (e.g., a pin, bolt, etc.), may be introduced into the substantially aligned apertures.
Of course, other arrangements and configurations of apparatus for connecting seismic braces to steel structural frames are also within the scope of the present invention. For example, another embodiment of connection apparatus that incorporates teachings of the present invention may comprise a ball-and-socket type connection apparatus. The first member, or frame-side member, of such a connection apparatus, which is securable to a steel structural frame, may comprise a socket. The socket may, for example, be in the form of an aperture with a concave edge. The coupling member of such a connection apparatus may comprise a ball, which may be spherical in shape, an oblong spheroid, disc-shaped, or otherwise configured to fit within the socket of the frame-side member and rotate somewhat relative to the frame-side member. The coupling member may also include one or more pins protruding from opposite sides thereof. The second member, or brace-side member, of a ball-and-socket type connection apparatus includes a pair of substantially planar members which are spaced apart a sufficient distance that the ball of the coupling member may be positioned therebetween. An aperture formed through each substantially planar member is configured to receive a portion of a pin protruding from the ball and, thus, facilitates hinged movement of the brace-side member and of a seismic brace to which the brace-side member is secured relative to one or both of the ball and the frame-side member of the connection apparatus.
In use, the frame-side member of a connection apparatus of the present invention is secured to a steel structural frame, such as in a corner formed between conjoined horizontal beams and vertical steel columns. Continuing with the above examples, this may be effected by welding or otherwise securing one or more gusset plates into such a corner. The brace-side member of the connection apparatus, which, preferably, has already been secured to or formed at the end of a core of a seismic brace, is then positioned appropriately relative to the frame-side member, such that apertures of the frame-side and brace-side members are substantially mutually aligned. A coupling member is then introduced into the aligned apertures so as to be positioned within each of the substantially aligned apertures of the frame-side and brace-side members. The coupling member is then secured in this position to prevent inadvertent removal thereof from the apertures. The opposite end of the seismic brace may then be similarly secured to another (higher or lower) horizontally extending steel beam. Alternatively, another type of connection, including a rigid, conventional connection, may be used to secure the other end of the seismic brace to the other horizontally extending beam. As a single pin is secured in position rather than several bolts, as required by conventional, rigid connection apparatus, erection of a seismic brace that includes a connection apparatus according to the present invention is simpler and faster than erection with conventional, rigid connection apparatus.
When a building that includes a frame with one or more seismic braces connected thereto by way of a connection apparatus of the present invention is subjected to a load, such as that generated by shock waves (e.g., seismic shock waves, high winds, etc.), the connection apparatus and the adjacent end of the seismic brace are substantially isolated from external moments that result from movement of the seismic brace out of the plane of the bay of a steel structural frame in which the seismic brace is located. The collar resists in-plane and out-of-plane moments on the exposed portions of the core of the seismic brace, as well as of the remainder of the connection apparatus, thereby permitting only substantially axial loads to be applied to the core, providing support to the core and the remainder of the connection apparatus, and preventing weak axis buckling of the core. In addition, the connection apparatus reduces the moments and shears that result from the application of gravity and earthquake loads to a steel structural frame by providing a larger moment of inertia at the ends of the core of a seismic brace. As a result, the connection element substantially limits the forces that are applied to the seismic brace to those which may be properly absorbed thereby.
As a further result of providing a nonrigid connection, the likelihood of a connection apparatus according to the present invention being damaged when subjected to gravity and earthquake loads is much lower than the likelihood of a conventional rigid connection being damaged. Thus, following failure due to absorption of excessive earthquake loads, a seismic brace which is at least partially secured to a steel structural frame by way of one or more of the inventive connection apparatus may still have some load-bearing capabilities and, thus, provide some structural support to a steel structural frame, whereas seismic braces that are secured in place by weakened conventional rigid connections would be less likely to provide such support.
Other features and advantages of the present invention will become apparent to those of ordinary skill in the art through a consideration of the ensuing description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
In the drawings, which illustrate various features of exemplary embodiments of the present invention:
FIG. 1 is a schematic representation of a bay of a steel structural frame with a pair of seismic braces, which are positioned within the bay in a conventional fashion, coupled to the steel structural frame;
FIG. 2 depicts an example of a conventional rigid connection between a steel structural frame and an exposed end of a yielding core of a seismic brace;
FIG. 2A is a cross-section taken along line 2 A— 2 A of FIG. 2 ;
FIG. 2B is a cross-section taken along line 2 B— 2 B of FIG. 2 ;
FIG. 3 is side view of an example of a seismic brace with which a nonrigid connection apparatus that incorporates teachings of the present invention may be used, as well as an exemplary embodiment of nonrigid connection apparatus;
FIG. 4 is a cross-section taken through line 4 — 4 of FIG. 3 ;
FIG. 5 is a side view of the embodiment of nonrigid connection apparatus shown in FIG. 3 ;
FIG. 6 is a perspective view of a brace-side member of the nonrigid connection apparatus of FIGS. 3 and 5 ;
FIG. 7 is a perspective view of a frame-side member of the nonrigid connection apparatus of FIGS. 3 and 5 ;
FIG. 8 is a perspective assembly view of another embodiment of nonrigid connection apparatus according to the present invention;
FIG. 9 is a perspective view of the nonrigid connection apparatus shown in FIG. 8 ;
FIG. 10 is a top view of the nonrigid connection apparatus of FIGS. 8 and 9 ;
FIG. 11 is a cross-sectional representation of a brace-side member of yet another embodiment of nonrigid connection apparatus according to the present invention;
FIG. 12 is a perspective assembly view of a ball-and-socket embodiment of nonrigid connection apparatus incorporating teachings of the present invention, which includes a coupling element comprising a ball;
FIG. 13 is a cross-section taken along line 13 — 13 of FIG. 12 ;
FIG. 13A a cross-sectional representation of a variation of the coupling element of the nonrigid connection apparatus shown in FIGS. 12 and 13 ;
FIG. 13B is a cross-sectional representation of another variation of the coupling element of the nonrigid connection apparatus shown in FIGS. 12 and 13 , which comprises a disc rather than a ball;
FIG. 14 is a side view of the nonrigid connection apparatus of FIGS. 12 and 13 ;
FIG. 15 is a top view of the nonrigid connection apparatus of FIGS. 12 through 14 ;
FIG. 16 is a side view of an example of use of the brace-side member of the nonrigid connection apparatus depicted in FIGS. 3–7 with a plurality of seismic braces; and
FIGS. 17–19 are cross-sectional representations of various examples of multiple-brace arrangements that may be used as shown in FIG. 16 .
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 3 and 4 , a seismic brace 100 that incorporates teachings of the present invention is depicted. In the illustrated example, seismic brace 100 is a single-core, compression and tension member which includes an elongate, substantially hollow exterior shell 102 , a buckling-limiting member, which is also referred to herein as “containment 106 ,” within exterior shell 102 , and an elongate yielding core 110 positioned substantially centrally within and extending completely along the length of containment 106 . The depicted yielding core 110 has a rectangular, somewhat planar cross-section, taken transverse to the length thereof, and includes ends 113 and 114 which extend beyond corresponding ends 103 , 104 of exterior shell 102 . Yielding core 110 is positioned within an aperture 108 that extends substantially through containment 106 and includes at least one surface 111 which is spaced apart from an interior surface 107 of containment 106 by way of a readily compressible medium 109 , such as a polymer, air, or the like. Although FIG. 3 depicts a particular embodiment of seismic brace 100 , which comprises a single-core member that may be subjected to compressive and tensile loads, other types of seismic braces, including all-steel seismic braces which lack a buckling-limiting member, may also be used in accordance with teachings of the present invention.
With continued reference to FIG. 3 , a brace-side member 130 of an exemplary embodiment of nonrigid connection apparatus 120 according to the present invention is located at at least one end 113 , 114 of yielding core 110 . Brace-side member 130 is also referred to herein as a second member, or simply as a member, of nonrigid connection apparatus 120 and as a nonrigid connection element.
As shown in FIG. 5 , brace-side member 130 includes an intermediate member, in this case an end plate 132 , which is secured to end 113 , 114 of yielding core 110 , such as by welds 134 . Brace-side member 130 also includes two knife plates 136 and 138 secured to and extending from end plate 132 in mutually parallel relation. Welds 140 or other known fixing means may secure knife plates 136 and 138 to end plate 132 . As shown, knife plates 136 and 138 may extend in substantially the same direction as seismic brace 100 ( FIGS. 3 and 4 ) and may be oriented substantially perpendicular to end plate 132 .
Turning to FIG. 6 , each knife plate 136 , 138 of brace-side member 130 of nonrigid connection apparatus 120 ( FIGS. 3 through 5 ) includes an aperture 137 , 139 , respectively formed therethrough. Apertures 137 and 139 , which are both configured to receive a central portion 162 ( FIG. 5 ) of a coupling member 160 ( FIG. 5 ) of nonrigid connection apparatus 120 , are in substantial alignment with one another.
With briefly returned reference to FIG. 3 , knife plates 136 and 138 of brace-side member 130 are spaced a sufficient distance apart from one another that a corresponding feature (e.g., gusset plate 152 of FIG. 7 ) of a frame-side member 150 of nonrigid connection apparatus 120 may be positioned therebetween.
As depicted in FIG. 7 , an exemplary embodiment of a frame-side member 150 of nonrigid connection apparatus 120 ( FIGS. 3 through 5 ) is shown. Frame-side member 150 is also referred to herein as a first member, or simply as a member, of connection apparatus 120 or as a nonrigid connection element. The illustrated frame-side member 150 comprises a single, substantially planar gusset plate 152 , which is configured to be fixed in place relative to a member of a steel structural frame 30 , such as one or more of a conjoined beam 34 and/or column 36 thereof. While gusset plate 152 is shown in the illustrated example as being secured in a corner formed at a junction between a horizontally oriented beam 34 and a vertically oriented column 36 , gusset plate 152 maybe secured to any suitable surface (i.e., within a bay 32 of steel structural frame 30 ) of a single beam 34 or column 36 . Also, while FIG. 7 depicts gusset plate 152 as being held in place by welds 153 , other fixing means for securing gusset plate 152 into position (e.g., rivets, bolts, etc., for securing gusset plate 152 to a lip (not shown) protruding from beam 34 and column 36 ) are also within the scope of the present invention.
The dimensions of gusset plate 152 and the type of fixing means used to secure the same to a steel structural frame 30 , including the height, length, and thickness thereof, are configured to withstand predetermined amounts of load, moment, and other stresses. Accordingly, the dimensions of gusset plate 152 depend at least partially upon the material (e.g., the type of steel) from which gusset plate 152 is fabricated, as well as the size of seismic brace 100 ( FIG. 3 ) to be used therewith, the location of a steel structural frame 30 at which seismic brace 100 is to be used, and other factors, as known in the art.
Gusset plate 152 of frame-side member 150 of connection apparatus 120 includes an aperture 154 therethrough. Aperture 154 may have substantially the same internal crosswise dimensions (e.g., radius) as apertures 137 and 139 ( FIG. 6 ) of substantially planar knife plates 136 and 138 , respectively, of brace-side member 130 of nonrigid connection apparatus 120 . Upon positioning substantially planar knife plates 136 and 138 on opposite sides of a gusset plate 152 which has been fixed into position relative to a steel structural frame 30 into an appropriate assembled relationship, apertures 137 and 139 of substantially planar knife plates 136 and 138 , respectively, are in substantial alignment with aperture 154 of gusset plate 152 .
Referring again to FIG. 5 , apertures 137 , 139 , and 154 are sized and configured to receive a central portion 162 of a coupling member 160 of nonrigid connection apparatus 120 . When positioned within apertures 137 , 139 , and 154 of assembled brace-side and frame-side members 130 and 150 , respectively, coupling member 160 nonrigidly couples brace-side member 130 and frame-side member 150 in the assembled relationship thereof. In this case, the nonrigid coupling is a hinged connection, at which movement may occur in substantially a single plane and at a substantially single pivot point.
Coupling member 160 is held in place within apertures 137 , 139 , and 154 by position-retaining elements 164 , such as enlarged heads or nuts at the ends thereof, bent regions at the ends thereof, securing elements that extend through apertures near the ends thereof, transversely to the length of the coupling member 160 (e.g., like cotter pins), or the like. Of course, combinations of different types of position-retaining elements 164 may be used to secure a coupling member 160 into place relative to frame-side member 150 and brace-side member 130 of nonrigid connection apparatus 120 .
With continued reference to FIG. 5 , a support collar 170 is also depicted. Support collar 170 includes a distal end 175 , which is configured to be positioned at or near brace-side member 130 of nonrigid connection apparatus 120 , and a proximal end 176 , which is configured to extend at least partially over an end 103 , 104 of exterior shell 102 . Proximal end 176 of support collar 170 may be permitted to slide relative to a length of exterior shell 102 . As proximal end 176 of support collar 170 is to be positioned over an end 103 , 104 of exterior shell 102 , at least the portion of a hollow center 173 thereof which is to receive an end 103 , 104 of exterior shell 102 has internal dimensions which are roughly the same as or slightly greater than the corresponding external dimensions of that end 103 , 104 . When properly positioned over an end 113 , 114 of a yielding core 110 of a seismic brace 100 ( FIGS. 3 and 4 ), support collar 170 substantially isolates yielding core 110 from external shear and moment, instead absorbing some of the external shear and moment and transmitting external shear and moment to exterior shell 102 . Thus, such positioning of seismic brace 100 isolates ends 113 , 114 against loads that are placed transversely on seismic brace 100 with respect to the axis or length thereof.
The exemplary support collar 170 which is shown in FIG. 5 includes first and second halves 171 and 172 , respectively. When assembled, first half 171 and second half 172 form an elongate structure with a substantially rectangular cross-section taken transverse to the length of the assembled support collar 170 and a hollow center 173 . First half 171 and second half 172 may be secured to one another by any suitable fixing means, including, without limitation, welds, rivets, nuts and bolts, and the like. As an alternative to the depicted embodiment of support collar 170 , support collar 170 may comprise a single piece. Other variations of support collars that incorporate teachings of the present invention and, thus, that are within the scope of the present invention include support collars with more than two pieces. Also, support collars that include a plurality of elements which are not secured directly to one another but, rather, which are secured to a seismic brace 100 ( FIGS. 3 and 4 ) and a brace-side member 130 of a nonrigid connection apparatus 120 are within the scope of the present invention.
FIGS. 8 through 10 depict another exemplary embodiment of nonrigid connection apparatus 120 ′ according to the present invention.
As shown in FIGS. 8 through 10 , a brace-side member 130 ′ of nonrigid connection apparatus 120 ′ includes a single, knife plate 136 ′ with an aperture 137 ′ formed therein. Knife plate 136 ′ may be secured, by appropriate fixing means, to an intermediate member, such as an end plate 132 ′, that has been secured to an end 113 , 114 of a yielding core 110 of a seismic brace 100 . Alternatively, knife plate 136 ′ may be secured directly to end 113 , 114 .
Frame-side member 150 ′ of nonrigid connection apparatus 120 ′ includes two substantially planar gusset plates 152 ′. Each gusset plate 152 ′ includes an aperture 154 ′ formed therethrough. Gusset plates 152 ′ of frame-side member 150 ′ are spaced apart from one another and oriented in substantially parallel relation to one another with apertures 154 ′ thereof in substantial axial alignment. The spacing between gusset plates 152 ′ is sufficient to permit the insertion of knife plate 136 ′ therebetween.
When knife plate 136 ′ is positioned between gusset plates 152 ′ in an appropriate assembled relationship thereof, aperture 137 ′ of knife plate 136 ′ and apertures 154 ′ of gusset plates 152 ′ are in substantial axial alignment with one another. Accordingly, a coupling member 160 of nonrigid connection apparatus 120 ′ may be introduced into apertures 137 ′ and 154 ′ and secured in place relative to both brace-side member 130 ′ and frame-side member 150 ′ of nonrigid connection apparatus 120 ′, as described previously herein with reference to FIG. 5 .
FIGS. 8 and 9 depict another exemplary support collar 170 ′ that may be used with nonrigid connection apparatus 120 ′ or any other embodiment of nonrigid connection apparatus that incorporates teachings of the present invention. Support collar 170 ′ includes four elongate members 172 ′, with cross-sections taken transverse to the length thereof having an “L” shape. A first end 173 ′ of each elongate member 172 ′ is secured (e.g., by welds or other suitable fixing means) to a corner 133 ′ of end plate 132 ′, while an opposite, second end 174 ′ of each elongate member 172 ′ is secured to an end 103 of exterior shell 102 . As there are four elongate members 172 ′ in the depicted example, one elongate member 172 ′ extends between each corner 133 ′ of end plate 132 ′ and a corresponding end 103 of exterior shell 102 .
In another, similar embodiment of nonrigid connection apparatus 120 ″, shown in FIG. 11 , brace-side member 130 ″ comprises an end 113 ″, 114 ″ of yielding core 110 ″ of seismic brace 100 ″. An aperture 137 ″ formed through end 113 ″, 114 ″ is configured to receive a central portion 162 ( FIG. 5 ) of a coupling member 160 of nonrigid connection apparatus 120 ″.
A frame-side member 150 ′ of nonrigid connection apparatus 120 ″ is the same as that shown and described previously herein with reference to FIGS. 8 through 10 and, thus, includes a pair of gusset plates 152 ′. Gusset plates 152 ′ of frame-side member 150 ′ are arranged substantially parallel to one another with apertures 154 ′ thereof in substantial axial alignment and are spaced apart a sufficient distance that end 113 ″, 114 ″ of yielding core 110 ″ may be positioned therebetween. Upon positioning end 113 ″, 114 ″ between gusset plates 152 ′ and substantially axially aligning aperture 137 ″ with apertures 154 ′, coupling member 160 may be placed within the substantially aligned apertures 154 ′ and 137 ″ so as to nonrigidly connect end 113 ″, 114 ″ to frame-side member 150 ′, as described previously herein with reference to FIGS. 5 and 8 through 10 . Coupling member 160 may then be secured in place, as described previously herein with reference to FIGS. 5 and 8 through 10 .
A support collar 170 ″ which is configured to be used with brace-side member 130 ″ includes an end plate 177 ″ with a slot 178 ″ formed therethrough to receive end 113 ″, 114 ″ of yielding core 110 ″. End plate 177 ″ is positioned at an intermediate location along end 113 ″, 114 ″ of yielding core 110 ″.
In addition to being useful with nonrigid connection apparatus of the types described herein, support collars (e.g., support collar 170 , 170 ′, 170 ″) that incorporate teachings of the present invention may also be used with other types of connection apparatus, including other nonrigid connection apparatus, as well as the nonrigid connection apparatus (e.g., gusset plate bolted to brace ends with cross-sections taken along the lengths thereof that are cruciform in shape).
Another exemplary embodiment of nonrigid connection apparatus 220 that incorporates teachings of the present invention is depicted in FIGS. 12 through 15 .
As shown in FIG. 12 , nonrigid connection apparatus 220 includes a brace-side member 230 , which is configured to be secured to a seismic brace 100 ( FIGS. 3 and 4 ), and a frame-side member 250 , which is configured to be secured to a steel structural frame. Nonrigid connection apparatus 220 also includes a coupling member 260 , which nonrigidly secures brace-side member 230 to frame-side member 250 and, thus, a seismic brace 100 to a steel structural frame 30 . As depicted, nonrigid connection apparatus 220 comprises a ball-and-socket type joint, with frame-side member 250 comprising the socket, coupling member 260 comprising the ball, and brace-side member 230 being pivotally secured to the ball of coupling member 260 .
As shown in FIGS. 12 and 13 , frame-side member 250 may comprise a pair of substantially planar gusset plates 252 with large apertures 254 formed therein. Each aperture 254 includes a concave edge 256 , the curvature of which is configured to complement at least a portion of an exterior surface of coupling member 260 so as to retain coupling member 260 within aperture 254 . Of course, the thickness of gusset plate 252 , the sizes of apertures 254 , and the curvatures of concave edges 256 may be configured to retain coupling member 260 under seismic and gravitational loads and, thus, when tensile and compressive loads are being applied to seismic brace 100 ( FIGS. 3 and 4 ).
Gusset plate 252 may be secured to one or more of a beam 34 and a column 36 of a steel structural frame 30 as known in the art, such as by welds, nuts and bolts, rivets, or the like.
FIGS. 12 and 13 illustrate coupling member 260 , which includes a ball 262 . As shown, ball 262 is spheroid in shape, comprising a sphere, although oblong spheroids are also within the scope of the present invention, as are spheres and spheroid structures that have substantially opposite planar surfaces. Ball 262 is configured to be introduced into aperture 254 of frame-side member 250 in such a way that an engaging region 263 of ball 262 is engaged by concave edges 256 of apertures 254 , between gusset plates 252 and, thus, retained at least partially within apertures 254 .
The exemplary coupling member 260 depicted in FIGS. 12 and 13 also includes an aperture 264 extending axially through ball 262 , as well as an elongate pin 266 positioned within aperture 264 so as to extend completely through ball 262 and to protrude from opposite sides thereof. Alternatively, as shown with respect to coupling member 260 ′ of nonrigid connection apparatus 220 ′ in FIG. 13A , two pins 266 ′ may be secured to opposite sides of a ball 262 ′ (e.g., by threadingly engaging apertures 268 ′ in opposite sides of ball 262 ′, as shown, by welds, etc.).
Of course, variations of coupling members are also within the scope of the present invention, including, without limitation, coupling member 260 ″ depicted in FIG. 13B , which includes a disc-shaped element 262 ″ with a coupling portion comprising a rounded ridge 263 ″ extending around at least a portion of the outer circumference thereof. Rounded ridge 263 ″ is configured to be engaged by a concave edge 256 ″ of an aperture 254 ″ of frame-side member 250 ″ of nonrigid connection apparatus 220 ″ in such a way that disc-shaped element 262 ″ may at least partially rotate about its axis A within aperture 254 ″, as well as move laterally, into and out of a plane P in which gusset plate 252 ″ is located, as shown by arrows 269 .
Like coupling members 260 and 260 ′, coupling member 260 ″ may include one or more pins 266 ″ protruding from opposite sides of disc-shaped element 262 ″. As shown, each pin 266 ″ may be positioned so as to extend substantially along axis A of disc-shaped element 262 ″.
With returned reference to FIG. 12 , as well as reference to FIGS. 14 and 15 , brace-side member 230 of nonrigid connection apparatus 220 may be configured substantially as brace-side member 130 described above with reference to FIGS. 3 through 6 . Thus, brace-side member 230 may include an end plate 232 , which is secured to end 113 , 114 of yielding core 110 ( FIGS. 3 and 4 ), to which two knife plates 236 and 238 are secured. Knife plates 236 and 238 extend from end plate 232 in mutually parallel relation. As shown, knife plates 236 and 238 may extend in substantially the same direction as seismic brace 100 ( FIGS. 3 and 4 ) and may be oriented substantially perpendicular to end plate 232 . Knife plates 236 and 238 are spaced a sufficient distance apart from one another that frame-side member 250 and ball 262 , 262 ′ or disc-shaped element 262 ″ of a respective coupling member 260 , 260 ′, 260 ″ may be positioned therebetween.
Each knife plate 236 , 238 of brace-side member 230 of nonrigid connection apparatus 220 includes an aperture 237 , 239 formed therethrough. Apertures 237 and 239 are both configured to receive a portion of a pin 266 , 266 ′, 266 ″ ( FIGS. 13 , 13 A, and 13 B, respectively) of a complementary coupling member 260 , 260 ′, 260 ″ in such a way that brace-side member 230 and, thus, a seismic brace 100 to which brace-side member 230 is secured, may pivot about an axis A defined by pins 266 , 266 ′, 266 ″.
As is apparent from the foregoing description, nonrigid connection apparatus 220 , 220 ′, 220 ″ allow a seismic brace 100 to pivot relative to frame-side member 250 in more than one plane. Accordingly, nonrigid connection apparatus 220 , 220 ′ and 220 ″ substantially isolate seismic brace 100 from shear, moment, and loads that are nonaxial to seismic brace 100 .
Turning now to FIGS. 16–19 , use of a brace-side member 130 of a nonrigid connection apparatus according to the present invention with a plurality of seismic braces 100 is depicted. In FIG. 16 , end plate 132 of brace-side member 130 is depicted as having yielding cores 110 of at least two seismic braces 100 secured thereto. Support collar 170 surrounds the adjacent end 103 , 104 of exterior shell 102 of each seismic brace 100 . FIG. 17 depicts a multi-brace embodiment that includes two seismic braces 100 with yielding cores 110 that are in a mutually parallel arrangement. FIG. 18 shows another multi-brace embodiment that includes three seismic braces 100 and 100 ′ that are arranged in a linear fashion. FIG. 19 illustrates yet another multi-brace embodiment that includes four seismic braces 100 in a two-by-two arrangement.
Multi-brace embodiments of the present invention are not limited to the depicted nonrigid connection apparatus 120 , but may also be used with other embodiments of nonrigid connection apparatus that incorporate teachings of the present invention. Moreover, while each of the seismic braces 100 , 100 ′ shown in FIGS. 16–19 includes an exterior shell 102 within which a yielding core 110 and a surrounding containment 106 are disposed, other types of seismic braces may also be secured to brace-side member 130 without departing from the scope of the present invention. In addition, it is within the scope of the present invention to secure two or more different types of seismic braces to the same brace-side member (e.g., brace-side member 130 ) of a nonrigid connection apparatus (e.g., nonrigid connection apparatus 120 ( FIG. 5 )) incorporating teachings of the present invention.
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 of the presently preferred embodiments. Similarly, other embodiments of the invention may be devised which do not depart from the spirit or scope of the present invention. Moreover, features from different embodiments of the invention 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. | A connection apparatus includes a frame-side member securable to a steel structural frame, a brace-side member securable to a seismic brace, and a coupling element that secures frame-side and brace-side members to each other. By way of example, the connection element may provide a hinge-type connection, which substantially isolates a seismic brace from nonaxial loads. As another example, the connection element may be a ball-and-socket type connection, which substantially isolates a seismic brace from nonaxial loads and absorbs any shear and moment applied thereto when the seismic brace drifts out of an intended plane of the steel structural frame. The connection element may also include a collar to stabilize the brace-side member and prevent shears and moments from causing the same to buckle in an unintended direction. Methods of installing and using the connection apparatus are also disclosed. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of priority to U.S. Provisional Patent Application No. 62/173,106 titled “Method and Apparatus for Preventing Voltage Flicker in a Power System” and filed June 9, 2015, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates generally to a method and apparatus for mitigating and preventing voltage flicker in an electrical power system.
BACKGROUND
[0003] Electric power is supplied to homes and industries through the electrical power system. The electrical power system is an interconnected network that includes power generating plants that produce electrical power, high-voltage transmission lines that carry power from distant sources to demand centers, and distribution lines that supply individual users with electricity. The transmission and distribution lines of the power system, or portions thereof, are often referred to as the grid, or power grid.
[0004] For electrical devices receiving electricity from the power system to function properly, the voltage of the electricity supplied by the power system must be of high quality. Voltage fluctuations, which are rapid and noticeable changes in the root mean square (rms) voltage level of the electricity supplied by the power system, can degrade the power quality and affect the performance of electrical devices. For instance, the effect of such voltage fluctuations can be perceived in visible changes of the brightness of a lamp, causing the light level of the lamp to fluctuate, or flicker. Thus, the term “flicker” or “voltage flicker” is often used to refer to such voltage fluctuations. Voltage flicker can be caused by a fluctuating electric load when various equipment or facilities change the load current on, for instance, the distribution level of the grid of the power system.
[0005] Regulators establish guidelines, or limits, for the maximum acceptable levels of voltage flicker that can be tolerated by customer electronic devices receiving electricity through the power system. One such guideline is shown in FIG. 1 , which is a voltage flicker tolerance curve from the IEEE Standard 141-1993/IEEE Standard 519-1992, known as the “GE Flicker Curve.” The GE Flicker Curve shows the point at which, for a given size and frequency of a voltage fluctuation (referred to as a dip), a typical person begins to perceive visible flicker in the brightness of a lamp, and the point at which a typical person would become irritated by such visible flicker.
[0006] When new facilities are installed on the electrical power system, or other changes that may affect the voltage levels are made to the electrical power system, such changes are evaluated for their impact on voltage flicker. The voltage flicker caused by such new facility installations or other changes typically must be within the acceptable levels set by regulators, for instance under the levels determined by the GE Flicker Curve. If the voltage flicker exceeds the flicker limits, costly equipment is often required to be added to the facility to bring the voltage flicker within acceptable levels.
SUMMARY
[0007] A method for mitigating voltage flicker in an electrical power system is provided. The electrical power system includes at least one power generating, energy storing, or power dissipating (load) facility connected to a power grid and a controller connected to the facility. The controller is configured to receive input signals from the facility, and to send control signals to the facility. The method includes measuring a value V d , which is a percent voltage dip caused in the power grid for a maximum change in power of the facility, M s ; receiving and storing in the controller the value V d , the value M s , a time interval T, and a voltage flicker tolerance curve; receiving in the controller a power value at time t and a power value at time t+T or at time t−T to determine a power change of the facility; calculating, for the power change of the facility, a flicker impact of the power change using the values of V d , T, and Ms and the voltage flicker tolerance curve stored in the controller; determining if the flicker impact of the power change causes the facility to exceed a flicker limit; and sending a control signal from the controller to the facility when the flicker impact of the power change is above the limit to adjust the facility.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a voltage flicker tolerance curve from IEEE Standard 141-1993/IEEE Standard 519-1992.
[0009] FIG. 2 shows an electrical power system with facilities coupled to a grid.
[0010] FIG. 3 shows a set-up portion of a method for preventing voltage flicker.
[0011] FIG. 4 shows a real-time portion of a method for preventing voltage flicker in an energy storage system.
[0012] FIG. 5 shows an electrical power system with an energy storage system connected between a power generation system and the grid.
DETAILED DESCRIPTION
[0013] The following detailed description should be read with reference to the drawings, in which identical reference numbers refer to like elements throughout the different figures. The drawings, which are not necessarily to scale, depict selective embodiments and are not intended to limit the scope of the invention. The detailed description illustrates by way of example, not by way of limitation, the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several example embodiments, adaptations, variations, alternative and uses of the invention.
[0014] This specification discloses a method and apparatus for mitigating or preventing voltage flicker in an electrical power system. FIG. 2 shows an example of an electrical power system 200 . Electrical power system 200 includes, for example, an electrical power generation system 220 , an energy storage system 230 , a consumer 215 , and a power dissipating (consuming) load 240 each connected to a grid 210 . The power generation system 220 , the energy storage system 230 and the load 240 are collectively referred to as facilities, each a facility. An electrical power system 200 may include numerous different types and numbers of facilities.
[0015] The power generation system 220 supplies the electrical power system with electricity and may be, for example, a fossil fuel burning plant, such as a coal burning plant, or a renewable energy installation, such as a wind farm or a solar energy installation.
[0016] The energy storage system 230 is supplied with and stores power from the power generation system 220 , and provides the stored power to the consumer 215 and the load 240 . The energy storage system 230 may be, for example, a battery energy storage system (BESS). Within the electrical power system 200 , at any time, the power generated by the power generation system 220 may exceed the power needed by the consumer 215 and the load 240 , particularly in the cases where wind farms and solar installations generate the power. Having energy storage system 230 connected to the grid 210 can reduce these inefficiencies by providing a mechanism to store surplus power generation so that consistent power can be provided.
[0017] The consumer 215 and load 240 both receive electrical power from the electrical power system 200 . The consumer may represent a variety of homes and businesses. The load 240 may, for example, represent a particular industrial use of electrical power that is large enough to have a noticeable effect on the electrical power system 200 .
[0018] The grid 210 may include high-voltage transmission lines and/or lower voltage distribution lines that conduct electricity provided by the power generation system 220 to the consumer 215 , the load 240 , and the energy storage system 230 . The high-voltage transmission lines and/or lower voltage distribution lines of the grid 210 also conduct electricity from the energy storage system 230 to the consumer 215 and the load 240 .
[0019] The grid 210 includes a regulation system 260 for ensuring that power is flowing smoothly through the grid 210 . The regulation system 260 also ensures that power generated by the power generation system 220 and stored in the energy storage system 230 is provided as needed to the consumer 215 and load 240 .
[0020] FIG. 2 also shows voltage management controllers 250 that prevent the facility to which they are connected from causing voltage flicker. Voltage management controllers 250 are connected, for example, between the grid 210 and each of the power generation system 220 , the energy storage system 230 , and the load 240 , and prevent the components of the electrical power system 200 to which it is connected from causing voltage flicker. The method disclosed herein for mitigating or preventing voltage flicker may be performed by a voltage management controller 250 . More details of the voltage management controller 250 will be described below.
[0021] FIG. 3 shows an initial set-up portion 300 of the method for preventing voltage flicker. In the initial set-up portion 300 of the method for preventing flicker, values of parameters are determined for the particular facility connected to grid 210 . The values of the parameters are then input and stored in the controller 250 for the facility and used in the real-time portion of the method for preventing flicker. The parameters determined are the maximum power swing for the facility, M s the time interval, T, the percent voltage dip, V d , that would occur in the grid 210 for a full cycle of a maximum power swing M s and the swing magnitude, S s , that would produce no impact on the grid 210 .
[0022] At step S 310 of the method, for the particular facility connected to grid 210 , the values of the maximum power swing, M s in MW, and the time interval, T, in seconds, are determined.
[0023] In general, the maximum power swing M s is the largest power change the facility is capable of. For example, if the facility is a battery used for an energy storage system 230 , the maximum power swing M s is the power change from full charge to full discharge. If, for example, the facility is a solar installation used for a power generation system 230 , the maximum power swing M s is the AC capacity of the solar installation. If, for example, the facility is a load 240 , the maximum power swing M s is the peak draw of the load.
[0024] In general, the time interval T is the minimum amount of time a ramp event (power change) will take to occur. For example, if the facility is a battery used for an energy storage system 230 , the time interval T can be the period of the interval between the regulatory signals that provide the battery with new power set points. The power set point is the amount of power the grid regulation system 260 determines the energy storage system 230 needs to provide to the electrical power system 200 at a given time. The regulation system 260 sends new power set points at a regular frequency, which corresponds to the time interval T for method 300 . If, for example, the facility is a solar installation used for a power generation system 230 that inputs power to the power system 200 , the time interval T may be the discrete time step which represents the minimal amount of time over which a large power deviation input to the power system 200 would occur, or T may be a test/sampling time step set by regulation system 260 . If, for example, the facility is a load 240 that draws power from the power system 200 , the time interval T may be the discrete time step which represents the minimal amount of time over which a large power deviation pulled off the power system 200 would occur, or T may be a test/sampling time step set by regulation system.
[0025] At step S 320 , for the particular facility connected to grid 210 , the percent voltage dip V d that would occur in the grid 210 for a full cycle of a maximum power swing M s is measured for that facility. Methods for measuring such percent voltage dip V d are known to persons having ordinary skill in the art, and such measurements may be made as part of a transmission study and/or interconnection study performed by regulators when the facility is connected to the power system 200 .
[0026] Referring again to FIG. 3 , at S 330 the values of M s , T, and V d are used along with the GE Flicker Curve ( FIG. 1 ) to determine the maximum swing magnitude S n that would produce no impact on the grid 210 . That is, for the given M s , T, and V d of the particular facility, the largest power change the facility can make without producing a voltage flicker in grid 210 is determined. Equation 1 provides S n :
[0000]
S
n
=
PVD
(
3600
T
)
V
d
*
M
s
Equation
1
[0000] where PVD(x) is the percent voltage dip as a function of the dips per hour (i.e., 3600/T where T has unit seconds) at the borderline of visibility for flicker, which is determined for example from the GE Flicker Curve. While the GE Flicker Curve is used herein as an example standard for setting the limits of acceptable voltage flicker, any other method for setting a limit of PVD(x) may be used. The method ensures that the impact of any facility on the grid 210 will not exceed the limits set by the standard used.
[0027] Once the values of M s , T, V d and S n are known, they can be used in the real-time portion of the method for preventing flicker. The method for preventing flicker uses Equation 2, below, to determine the flicker impact F i caused by a power change ΔP of the facility:
[0000]
F
i
=
1
D
P
H
(
abs
(
Δ
P
)
M
S
*
V
d
)
Equation
2
[0000]
(
abs
(
Δ
P
)
M
S
*
V
d
)
[0000] In this equation is the percent voltage dip resulting from the power change ΔP, and DPH(x) is the maximum number of dips per hour of that magnitude that are allowed if the facility is to stay within the borderline of visibility for flicker. DPH(x) is determined for example from the GE Flicker Curve ( FIG. 1 ). For example, if the power change is the maximum power swing M s , the maximum number of dips per hour that are allowed is DPH(V d ), which may be read from the GE Flicker Curve at percent voltage dip=V d . As noted above, while the GE Flicker Curve is used herein as an example standard for setting the limits of acceptable voltage flicker, any other flicker tolerance curve for setting a limit of DPH(x) may be used.
[0028] How the power change ΔP is determined in Equation 2 depends on the particular type of facility, and the adjustment made to the power system based on the results of the flicker impact also depends on the particular facility. Thus, application of Equation 2 to an energy storage system 230 such as a BESS, a power generation system 220 , such as a solar installation, and a load 240 , such as an industrial application, will be described in turn below.
[0029] FIG. 4 shows the real time portion of the method for preventing flicker 400 as used for an energy storage system facility 230 . When an energy storage system 230 , such as a BESS, is connected to grid 210 , the regulation system 260 sends power level requests to the energy storage system 230 at time intervals T. That is, as the regulation system 260 for the electrical power system 200 determines that more or less power is needed by consumer 215 and/or load 240 , the amount of power output from the energy storage facility 230 is changed. Each new power level request provides a new set point for the output of the energy storage system 230 . When the new power level request set point SP t is received, the real time portion of the method 400 in FIG. 4 is performed.
[0030] At step S 440 of the method of FIG. 4 , the flicker impact of changing the power output level to the next requested set point is determined. The values of M s , T, V d , S n , SP t−1 (current set point) and SP, (next set point) are input into Equation 3 below. Equation 3 is just Equation 2, described above, with ΔP determined by the set point values: ΔP=SP t −SP t−1 .
[0031] Thus, in Equation 3, the percentage voltage dip is determined by the absolute value of the change in the set points abs(SP t −SP t−1 ). The input values are then used at step S 440 in Equation 3 to calculate the flicker impact of moving to the next set point:
[0000]
F
i
=
1
D
P
H
(
abs
(
SP
t
-
SP
t
-
1
)
M
S
*
V
d
)
Equation
3
[0032] In Equation 3 DPH(x) is the maximum number of dips per hour that are allowed if the facility is to stay within the borderline of visibility for flicker, as determined from the GE Flicker Curve for example, for the percent voltage dip resulting from the power change ΔP arising from changing the power to the new set point.
[0033] Once the flicker impact of changing the power output level of the energy storage system to the next requested set point is determined, at step S 450 it is determined whether or not moving to the next set point exceeds the flicker limit. As shown in Equation 2 and Equation 3 and described above, the flicker impact of any given voltage dip is equal to the inverse of the maximum number of voltage dips of that magnitude that are allowed per hour if the facility is to stay within the borderline of visibility for flicker. Hence Equation 2 and Equation 3 can be rewritten as shown below in Equation 4:
[0000] F i ( d h )= d h −1 Equation 4
[0000] where d h is the dips per hour allowed for any given voltage swing in question. The maximum cumulative rolling hour flicker impact is shown in Equation 5:
[0000] F i ( d h )* d h =d h −1 * d h =1 Equation 5
[0000] The method uses the dimensionless flicker limit of 1 as shown in Equation 5 and determines if the accumulated flicker impact from the facility's previous rolling hour of operation plus the impact from the next set point exceeds this limit. Referring again to FIG. 4 , in step S 450 , the method checks if moving to the next set point will exceed the flicker limit using Equation 6:
[0000]
F
i
t
+
∑
t
=
t
-
1
hr
t
=
t
-
1
F
i
t
<
1
Equation
6
[0034] The left side of Equation 6 adds the flicker impact of the power change ΔP of the facility to the flicker impacts of all other power changes of the facility that occurred in the hour previous to time t. As shown in step S 460 , if Equation 6 is true, then the flicker limit will not be exceeded, and the change to the new set point can proceed. If, on the other hand, Equation 6 is not true (S 470 ), then the power output is moved in the direction of the proposed set point by the magnitude of the swing that would produce no impact on the grid 210 , as shown in Equation 7:
[0000]
SP
=
SP
t
-
1
+
SP
t
-
SP
t
-
1
abs
(
SP
t
-
SP
t
-
1
)
*
S
n
Equation
7
[0000] where SP is the adjusted set point for the new power output level that will produce no impact on the grid 210 and will be used instead of the requested set point SP t for which the power level output change would exceed the flicker limit.
[0035] Although Equation 6 sums flicker impacts over a one hour period, Equation 6 may instead be recast to add the flicker impact of the power change ΔP of the facility to the flicker impacts of all other power changes of the facility that occurred over any other suitable predetermined time period. In such cases the flicker impact used in the recast equation is defined as the inverse of the maximum number of voltage dips of a given magnitude that are allowed per such predetermined time period. Any suitable predetermined time period may be used to define flicker impacts and in Equation 6 to test whether or not the flicker impact of a power change ΔP causes the facility to exceed a flicker limit.
[0036] In the example shown in FIG. 4 , the facility is an energy storage system 230 . However, the method may be applied to other facilities as well.
[0037] If the facility is a power generation system 220 , such as a solar installation, the method can be applied as follows. The power output by a power generation system 220 , such as a solar installation, may be subject to fluctuations. For example, the power generated by a solar installation depends upon the amount of sunlight received by the solar panels. If there are sudden changes in the sunlight, for example, if there are clouds blowing across the solar installation that block or partially block the sunlight, the solar installation will, during that time period, produce less power. If the power produced by the power generation system 220 is output directly to the grid 210 , such sudden changes can cause voltage flicker. Equation 8 below determines the flicker impact due to power changes for interval T. While the energy storage system 230 described above receives set points and determines the flicker impact for a new set point before proceeding to provide power at the next set point, the method applied to the power generation system 220 uses, as shown in Equation 8, the actual power provided.
[0000]
F
i
=
1
D
P
H
(
abs
(
Pout
t
-
Pout
t
-
T
)
M
S
*
V
d
)
Equation
8
[0000] In Equation 8, ΔP=Pout t −Pout t−T , where Pout t is the power output at time t and Pout t−T is the previous power output.
[0038] Once the flicker impact F i is determined, it is used with Equation 6 above to determine if the power output level has exceeded or is close to the flicker limit. If so, then adjustments can be made to the power generation system.
[0039] One method for adjusting based on the flicker impact F i determination is shown in FIG. 5 . FIG. 5 illustrates an electrical power system 500 . In FIG. 5 , the power generation system 520 is, for example, a solar or wind energy generation system and the energy storage system 530 is, for example, a BESS. The energy storage system is connected between the grid 510 and the power generation system 520 in order to regulate the impact of the power generation system 520 on the grid 510 . Thus, the energy storage system 530 receives the solar or wind energy and may be tightly looped with the power generation system 520 to determine if the power produced in the power generation system 520 can be put into the grid 510 in real time. If, using Equation 6 and Equation 8, as described above, in controller 550 , it is determined that the flicker limit is not exceeded, then the power produced by power generation system 550 would simply pass through to the grid 510 . Otherwise, if the flicker limit is exceeded, the energy storage system 530 would intervene and store excess power produced in the power generation system 520 or interject excess power into the grid 510 . Power interjected into the grid 510 from the energy storage system 530 is under the control of the controller 555 which uses Equation 3, Equation 6, and the method described above. Thus, the energy storage system 530 absorbs or injects energy such that the sum of the power from the power generation system 520 and the energy storage system 530 does not exceed the flicker limit. The regulation system 560 may be notified. In conventional methods for managing power, power generation from, for example, a solar or wind energy generation system, is not input into the grid in real time, but the method describe above may allow for real-time input of the power.
[0040] In another example, the method can be used with a load 240 . In this case, as shown in Equation 9, the flicker impact is determined for power changes in the amount of power removed from the grid 210 , and ΔP=Pin t −Pin t−T where Pin t is the power load 240 draws from the grid 210 at time t, and Pin t−T is the amount of power drawn from grid 210 at the prior interval time t−T.
[0000]
F
i
=
1
D
P
H
(
abs
(
Pin
t
-
Pin
t
-
T
)
M
S
*
V
d
)
Equation
9
[0041] The flicker impact determined for load 240 at time t is then used with Equation 6 above to determine if the power drawn from the grid 210 has exceeded the flicker limit. If so, then adjustments can be made such as by using an energy storage system between the load 240 and grid 210 similar to what is described above with respect to the power generation system, except that the energy storage system provides energy directly to the load 240 if the flicker limit is exceeded.
[0042] A controller may be used to implement the method for preventing flicker. Referring to FIG. 2 , the controllers 250 which implement the method are connected to both the regulation system 260 for the grid 210 and to the controls of the facility ( 220 , 230 , 240 ) to which the controller 250 is attached. The M s , T, V d and S n information is input into, and may be stored in, the controller 250 . The controller also stores the data in the GE Flicker Curve, or other flicker tolerance curve used to set the limits on voltage flicker. The controller 250 is configured to receive power information for the facility. For instance, for the energy storage system 230 , the controller receives the power set point information from the regulatory system 260 . Using the inputted M s , T, V d , and S n values, and the received power information along with the GE Flicker Curve, controller 250 performs the method for preventing voltage flicker. The controller 250 then signals the facility ( 220 , 230 , 240 ) to adjust as determined by the method. For instance, if the facility is an energy storage system and the new set point will not exceed the flicker limit, then the controller 250 provides the new set point to the energy storage system 230 .
[0043] The controller 250 may be implemented as a separate unit at the facility connected to the regulation system 260 and the controls for the facility, as shown in FIG. 2 , or controller 250 may be connected only to the facility ( 220 , 230 , 240 ). Alternatively, controller 250 may be implemented through a SCADA system (supervisory control and data acquisition system), for example, and provide signals to a remote facility from a more centralized control system (not shown in FIG. 2 ).
[0044] This disclosure is illustrative and not limiting. Further modifications will be apparent to one skilled in the art in light of this disclosure and are intended to fall within the scope of the appended claims. | A method mitigates or prevents voltage flicker in an electrical power system that includes at least one power generating, energy storing, or power dissipating facility connected to a power grid and a controller connected to the facility. The method includes receiving in the controller a power value at a present time t and a power value at time t+T or at time t−T to determine a power change of the facility, calculating a voltage flicker impact on the power grid of the power change, determining if the flicker impact of the power change is above a limit, and sending a control signal from the controller to the facility when the flicker impact of the power change is above the limit to adjust the facility. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119 to Korean Patent Application No. 10-2010-0086571, filed on Sep. 3, 2010 and Korean Patent Application No. 10-2011-0088127, filed on Aug. 31, 2011, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
The present invention relates to a resin composition for a sheet, and more particularly to an eco-friendly poly(alkylene carbonate) resin composition containing a poly(alkylene carbonate) resin capable of efficiently utilizing carbon dioxide, which is a major contributor to global warming, as a main material, and containing three or more kinds selected from the group consisting of an strength controller, a flexibilizer, a dimensional stabilizer, an impact modifier, a filler, a obliterating power improver, a foaming agent, a foaming cell control agent, a flame retardant, an flameproofing agent, an antifogging agent, and a lubricant.
BACKGROUND
A polyvinyl chloride material used in housing of human or office spaces has been requested or restricted such that a polyvinyl chloride resin is not used for toys for children, food packing, bags for Ringer in hospitals, or the like, by the Ministry of Environment and the authorities concerned, due to environmental pollution and harmfulness to the human body, inside or outside the country. Furthermore, the use thereof has been steadily restricted abroad, particularly in Europe, such as, regulating import and export customs clearance of products containing the polyvinyl chloride resin. The main reason is that products made of polyvinyl chloride materials are difficult to recycle, and thus are incinerated as waste, thereby generating a large amount of harmful gases such as hydrogen chloride (HCl), and dioxin, which are fatal to the human body.
Specifically, since the polyvinyl chloride material is alone not made into products fundamentally, processing additives, such as plasticizers, stabilizers, flame retardants, dyes, and the like, are used in order to solver the above problems, and these materials incur the harmful gases and dioxin. Among the processing additives, a phthalatebased plasticizer used in order to impart workability and flexibility to the polyvinyl chloride is an environmental hormone, and thus has a fatal effect on the human and natural ecosystem. Therefore, four plasticizer maker companies made an agreement in respect to restricting the use of polyvinyl chloride in the country. Stabilizers and dyes have been determined to be very fatal to the human body and natural ecosystem since they contain heavy metals that are fatal to the human body, and thus, the use thereof is restricted.
Alternatives using eco-friendly common plastics have been developed in order to solve problems of these polyvinyl chloride products. However, the alternatives have problems related to physical properties; for example, they can be easily broken in the winder time due to deficiency in flexibility. Furthermore, processing additives need to be additively used since they are poor in printability, cut-ability, and adhesive property thereof, and thus, incur an increase in costs. Moreover, economic feasibility is lowered due to production by extrusion processing and high price of materials themselves.
SUMMARY
An embodiment of the present invention is directed to providing an object of overcoming deterioration in post processability, such as printability, cut-ability, adhesive property, or the like, and deterioration in physical properties of products made of modified polyethylenes, which are eco-friendly common plastics, such as polypropylene, polyethylene terephthalate, polyurethane, thermoplastic olefin based resin, acrylic resin, and the like, as alternatives of polyvinyl chlorides, by using a poly(alkylene carbonate) resin as a main material and adding a minimal processing additives not harmful to the human body and natural ecosystem.
An embodiment of the present invention is directed to providing an object of allowing products made of a poly(alkylene carbonate) resin composition according to the present invention to have excellent a flameproofing property and improved smoke density, thereby preventing a large amount of fatal and harmful gases, which are unfavorable as an interior material, from being generated at the time of a fire.
An embodiment of the present invention is directed to providing an object of overcoming a weakness that a pellet type polymer material is difficult in calender processing and thereby to remarkably lower production costs as compared with extrusion processing, performing a process at lower temperature than a polyvinyl chloride resin and thereby improve the workability, and lowering specific gravity and thereby reduce the manufacturing costs of production companies.
In one general aspect, a resin composition for a sheet includes: 0.1 to 100 parts by weight of an strength controller, 0.1 to 50 parts by weight of a flexibilizer, 0.1 to 30 parts by weight of a obliterating power improver, 0.1 to 200 parts by weight of a filler, and 0.1 to 5 parts by weight of a lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
The resin composition for a sheet may further include 0.1 to 5 parts by weight of a compatibilizer based on 100 parts by weight of the poly(alkylene carbonate) resin.
The resin composition for a sheet may further include 0.1 to 30 parts by weight of an impact modifier based on 100 parts by weight of the poly(alkylene carbonate) resin.
The resin composition for a sheet may further include 0.5 to 20 parts by weight of a foaming agent or 0.1 to 200 parts by weight of a flame retardant based on 100 parts by weight of the poly(alkylene carbonate) resin.
The resin composition for a sheet according to the present invention necessarily includes the additives having the above content ranges together with the poly(alkylene carbonate) resin, thereby improving post processability, such as mechanical property, processability, printability, cut-ability, adhesive property, or the like, or anti-flame property, and allows calender processing, resulting in remarkably lowering production cost as compared with extrusion processing, thereby improving economic feasibility.
The strength controller is a polymer resin having a high glass transition temperature, which is added in order to improve mechanical property (tensile strength, tear strength, or the like) of plastics having a low glass transition temperature (Tg), and functions to additively improve heat-resistant property and dimensional stability of products besides the mechanical property. The strength controller may include a polyolefin based resin such as polyethylene and polypropylene, an ethylene vinyl acetate resin, a polymethylmethacrylate resin, polylactic acid, or a biodegradable resin of modified polyester resins, and be any one or more selected from linear low density polyethylene, random polypropylene, polymethylmethacrylate, polylactic acid, and ethylene vinyl acetate. The flexibilizer may be any one or more selected from acrylate based compounds and glutaric acid compounds.
The strength controller is in a pellet type or a liquid type, and a modified polyester or thermoplastic copolyester elastomer having a number average molecular weight of 200 to 500 may be used as the strength controller.
The strength controller is contained in 0.1 to 100 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin. If the concentration of the strength controller deviates from the above range, a synergy effect in improvement of physical property due to combination with other components is decreased, and thus, improvement in the heat resistant property or dimensional stability of the products can not be expected, and physical properties such as tensile strength, tear strength and the like, are deteriorated.
In addition, in a case where the polyolefin based resin is used as the strength controller, the compatibilizer may be used. The compatibilizer can function to obtain a blend having a uniform compositional ratio and perform an important role in improvement of physical properties, by improving fusion or melting with polyolefin.
As the compatibilizer, a polyethylene based type including polyethylene and maleic anhydride, a polypropylene based type including polypropylene and maleic anhydride, an ethylene vinyl acetate type including ethylene vinyl acetate, polystyrene, and maleic anhydride, or a linear low density polyethylene type including linear low density polyethylene and maleic anhydride. Here, the linear low density polyethylene based compounds may have a melt index (190° C., ASTM D1238) of 0.3 to 0.9 g/10 min and a density of 0.5˜2.0 g/cm 3 .
The compatibilizer may be included in 0.1 to 5 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin, thereby improving physical properties such as tensile strength, tear strength, elongation, and the like, processability, dimensional stability, and cold resistant property through combination with other components.
The filler may be an inorganic filler including calcium carbonate, talc, white clay, titanium dioxide, magnesium carbonate, barium carbonate, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, zinc oxide, white carbon, or amorphous silica, or an organic filler including a melamine resin or an urea resin.
The filler is contained in 0.1 to 200 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin. If the concentration of the filler deviates from the above range, a synergy effect due to combination with other components may be decreased, and there may be deterioration in rigidity of products and shrinkage and deformation of the products.
The lubricant is added to plastics during processing and finely coated on surfaces of the plastics, and thereby to reduce friction between polymer processing apparatuses and between polymer-polymer. As a result, the lubricant increases productivity of products, and prevents adhesion between plastics to facilitate the use of sheet or film typed products. The lubricant may be used for improving the heat resistant property of the final product, and preventing respective sheets from being adhered to each other at the time of winding the final product. The lubricant may be stearic acid or dioctyl terephthalate.
The lubricant is contained in 0.1 to 5 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin. If the concentration of the lubricant deviates from the above range, a melt viscosity is too low such that processability deteriorates, and thus, improvement in physical properties can not be expected through combination with other components.
Examples of the impact modifier may include any one or more selected from methylmethacrylate-butadiene-styrene (MBS) copolymer which is poor in heat resistant property, chemical resistant property, and weather resistant property but excellent in impact strength, acrylic based Impact modifier (AIM) which is lower than a butadiene type impact modifier in impact strength but excellent in heat resistant property and chemical resistant property, or chlorinated polyethylene (CPE) which is favorable in view of costs than physical properties. Here, as for the impact modifier for use in opacity, an apparent specific gravity is 0.25 g/cc or more, and grains not passing through #10 mesh are contained in 3 wt % and grains passing through #200 mesh are contained in 35 wt %. A volatile matter is contained in 1 wt % or less. The izod impact strength (ISO 180) is 50 kg·cm/cm or more (23° C. ¼″) and 10 kg·cm/cm or more (−30° C. ¼″). As for the impact modifier for use in transparency, an apparent specific gravity is 0.32 g/cc, and grains not passing through #24 mesh are contained in 2 wt % and grains passing through #200 mesh are contained in 20 wt %. A volatile matter is contained in 1 wt % or less. The izod impact strength (ISO 180) is 80 kg·cm/cm or more (23° C.).
The impact modifier is contained in 0.1 to 5 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin. If the concentration of the impact modifier deviates from the above range, a hardened product may be easily broken, which causes deterioration of durability thereof.
The foaming agent is an additive used in forming cells to prepare a foaming body, by inputting gas in polymer within a state where polymer materials and various kinds of sub-raw materials are added, in physical, chemical and mechanical methods, through regulation of conditions, such as temperature, pressure, time and the like, and thereby to forming cells, or artificially forming gas. Among chemical foaming agents, sodium bicarbonate, ammonium carbonate, ammonium bicarbonate, ammonium nitrite, an azide compound, sodium borohydride, soft metal, or the like, causes an endothermic reaction at the time of thermal decomposition. Inorganic foaming agents showing irregular decomposition and generating gas somewhat slowly may be used. Since the gas generated by decomposition of the foaming agent is almost carbon dioxide, the foaming agent may be used in manufacturing an open-cell structured foaming body due to large permeability thereof to the resin. The foaming agent may be used with an organic foaming agent including azodicarbonamide (ADCA), N,N′-dinitrosopentamethylenetetramine (DNPA), 4,4′-oxybis(benzenesulfonylhydrazide) (OBSH), p-toluenesulfonylhydrazide (TSH). Any one or more selected from the group consisting of inorganic foaming agents and organic foaming agents.
The foaming agent is contained in 0.5 to 20 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin, and can improve light weight, elasticity, insulation property, soundproofing property, and absorbency, and provide an excellent appearance, through combination with other components within the above range.
The flame-retardant agent may be any one or more selected from the group consisting of phosphorus based compounds, silicon based compounds, halogen based compounds, and metal hydride compounds, and can give, to the products, impact relieving property, cushion feeling, excellent touch feeling, cost reduction, dimensional stability, adiabaticity, soundproofing property, buoyancy, absorbency, decorating property, or the like.
The flame retardant agent is contained in 0.1 to 200 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin, thereby improving flame retardant property and flameproofing property, and expressing a synergy effect through combination with other components.
In the present invention, the flexibilizer is referred to a single molecular type liquid material or a polymer type solid material, which can be processed below a decomposition temperature of a polymer material or lower for use in improving processability of the polymer, and can be added to improve flexibility of the polymer material. The flexibilizer can minimize the generation of a frictional heat, improve physical properties such as elasticity, adhesive property, flexibility, and or the like, improve thermal stability of products, and easily melt a pallet type polymer material.
In the present invention, as the flexibilizer, DAIFATTY-101 or MTGA of the structural formula below may be used. Even though the optimum content of the flexibilizer, based on the poly(alkylene carbonate) resin, is a level of ⅙ as compared with a common phthalate based plasticizer used for the polyvinyl chloride resin, it exhibits mechanical properties and hardness equal to or superior to the common phthalate based plasticizer, and has excellent migrant resistant property (migration of plasticizer).
MTGA(Bis(2-(2-(2-methoxyethoxy)ethoxy)ethyl glutarate)
The flexibilizer also includes a solid type polyacrylic acid or polyacrylates obtained by a polymerization reaction or esterification reaction of acrylic acid or acrylates. Here, as the flexibilizer, an acrylic resin obtained by treating 60 to 85% of polymethylmethacrylate, 15 to 5% of polyethylacrylate, and 25 to 5% of polybutylacrylate with a polar solvent may be used in order to maximize mechanical properties and heat resistant property, and PA828 (LG Chemical) may be one example of the flexibilizer.
The flexibilizer is contained in 0.1 to 50 parts by weight based on 100 parts by weight of the poly(alkylene carbonate) resin, thereby remarkably improving fusion and processability through combination with other components, increasing elasticity, adhesive property, and flexibility, and enhancing thermal stability.
In the present invention, a obliterating power improver is for improving a whiteness, tinting strength, an aesthetic effect, and coverage, and is applicable to sheets for wall paper or decoration. An example of the coverage improve may be titanium dioxide, but not limited thereto.
In the present invention, an elasticity provider can improve durability, and particularly is applied to foaming products of synthetic leather, thereby maximizing an effect of improving elasticity and enhancing dimensional stability. Examples of the elasticity provider may include NBR or modified polyurethane.
Meanwhile, moisture is condensed due to the breathing of contents packaged (package of mainly vegetables, fruits, and food) by a material mainly used in plastic wrap for package or difference of temperature between an inside surface and an outer surface of the packaging. As a result, the contents are scarcely seen when a customer purchases the products, and thus, freshness of the contents is difficult to confirm, which causes a purchase degree to be dropped. In addition, when the condensed moisture is contacted with the packaged contents, the contents may be easily spoiled. In the present invention, an antifogging agent can prevent these problems. A surfactant may be used as the antifogging agent.
In another general aspect, a resin composition for a sheet includes: 0.1 to 100 parts by weight of an strength controller, 0.1 to 50 parts by weight of a flexibilizer, 0.1 to 5 parts by weight of a compatibilizer, 0.1 to 30 parts by weight of a obliterating power improver, 0.1 to 200 parts by weight of a filler, and 0.1 to 5 parts by weight of a lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
In another general aspect, an eco-friendly poly(alkylene carbonate) resin composition for a decorative sheet includes at least one selected from the group consisting of 2 to 50 parts by weight of an strength controller, 2 to 50 parts by weight of a dimensional stabilizer, 0.1 to 30 parts by weight of a flexibilizer, 0.1 to 30 parts by weight of an impact modifier, 5 to 30 parts by weight of a coverage improver, and 0.1 to 5 parts by weight of a filler, based on 100 parts by weight of a poly(alkylene carbonate) resin.
A poly(alkylene carbonate) resin (GreenPol) in the eco-friendly poly(alkylene carbonate) resin composition is excellent in tensile strength and tear strength, due to structural distinctiveness of itself and good miscibility with processing additives, and is remarkably excellent in particularly elongation (stretching property) and printability, as compared with common plastics. These physical properties are importantly required for use in a high-priced membrane in the decorative sheets. In particular, the poly(alkylene carbonate) resin (GreenPol) is excellent in a flameproofing characteristic, such as smoke density, by 1/600 of that of the common plastics.
Here, the eco-friendly poly(alkylene carbonate) resin composition for a decorative sheet may be used as a transparent or opaque soft decorative sheet, or a transparent or opaque hard decorative sheet, by combination with the strength controller, the dimensional stabilizer, the flexibilizer, the impact modifier, the obliterating power improver, or the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for the transparent soft decorative sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 0.1 to 30 parts by weight of the flexibilizer, and 0.1 to 5 parts by weight of the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for the opaque soft decorative sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 0.1 to 30 parts by weight of the flexibilizer, 5 to 30 parts by weight of the obliterating power improver, and 0.1 to 5 parts by weight of the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for the transparent hard decorative sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 0.1 to 30 parts by weight of the impact modifier, and 0.1 to 5 parts by weight of the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for the opaque hard decorative sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 0.1 to 30 parts by weight of the flexibilizer, 5 to 30 parts by weight of the obliterating power improver, and 0.1 to 5 parts by weight of the lubricant.
The poly(alkylene carbonate) resin is excellent in tensile strength and tear strength, due to structural distinctiveness of itself and good miscibility with processing additives, and is remarkably excellent in particularly elongation (stretching ratio) and printability, as compared with common plastics. These physical properties are importantly required for use in a high-priced membrane in the decorative sheets. Also, the poly(alkylene carbonate) resin is excellent in a flameproofing characteristic (particularly smoke density), by 1/600 of that of the common plastics.
The poly(alkylene carbonate is prepared by copolymerization of carbon dioxide and at least one epoxide compound selected from the group consisting of (C2-C20)alkyleneoxide substituted or unsubstituted with halogen, (C1-C20)alkyloxy, (C6-C20)aryloxy, or (C6-C20)ar(C1-C20)alkyl(aralkyl)oxy; (C4-C20)cycloalkyleneoxide substituted or unsubstituted with halogen, (C1-C20)alkyloxy, (C6-C20)aryloxy or (C6-C20)ar(C1-C20)alkyl(aralkyl)oxy; and (C8-C20)styreneoxide substituted or unsubstituted with halogen, (C1-C20)alkyloxy, (C6-C20)aryloxy, (C6-C20)ar(C1-C20)alkyl(aralkyl)oxy, or (C1-C20)alkyl.
Here, the epoxide compounds may be at least one selected from the group consisting of ethylene oxide, propylene oxide, butene oxide, pentene oxide, hexene oxide, octen oxide, decene oxide, dodecene oxide, tetradecene oxide, hexadecene oxide, octadecene oxide, butadiene monoxide, 1,2-epoxide-7-octene, epifluorohydrine, epichlorohydrine, epibromohydrine, glycidyl methyl ether, glycidyl ethyl ether, glycidyl normal propyl ether, glycidyl sec-butyl ether, glycidyl normal or isopentyl ether, glycidyl normal hexyl ether, glycidyl normal heptyl ether, glycidyl normal octyl or 2-ethyl-hexyl ether, glycidyl normal or isononyl ether, glycidyl normal decyl ether, glycidyl normal dodecyl ether, glycidyl normal tetradecyl ether, glycidyl normal hexadecyl ether, glycidyl normal octadecyl ether, glycidyl normal icocyl ether, isopropyl glycidyl ether, butyl glycidyl ether, t-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, cyclopentene oxide, cyclohexene oxide, cyclooctene oxide, cyclododecene oxide, alpha-pinene oxide, 2,3-epoxide norbonene, limonene oxide, dieldrin, 2,3-epoxide propyl benzene, styrene oxide, phenyl propylene oxide, stilbene oxide, chlorostilbene oxide, dichlorostilbene oxide, 1,2-epoxy-3-phenoxypropane, benzyl oxymethyl oxirane, glycidyl-methylphenyl ether, chlorophenyl-2,3-epoxide propyl ether, epoxypropyl methoxyphenyl ether, biphenyl glycidyl ether, glycidyl naphthyl ether, glycidyl acetic acid ester, glycidyl propionate, glycidyl butanoate, glycidyl normal pentanoate, glycidyl normal hexanoate, glycidyl heptanoate, glycidyl normal octanoate, glycidyl 2-ethyl hexanoate, glycidyl normal nonanoate, glycidyl normal decanoate, glycidyl normal dodecanoate, glycidyl normal tetradecanoate, glycidyl normal hexadecanoate, glycidyl normal octadecanoate, and glycidyl icosanoate.
Also, the poly alkylene carbonate may be represented by Chemical Formula 1 below.
[In Chemical Formula 1, m represents an integer of 2 to 10, n represents an integer of 1 to 3, R represents hydrogen, (C1-C4)alkyl or —CH 2 —O—R′ (R′ is (C1-C8)alkyl), x represents an integer of 5 to 100, y represents an integer of 0 to 100.]
The alkylene in the polyalkylene carbonate of the present invention may include ethylene oxide, propylene, 1-butylene, cyclohexene oxide, alkylglycidyl ether, n-butyl, n-octyl, and the like, and is not limited thereto.
The polyalkylene carbonate is prepared by alternating copolymerization of carbon dioxide and at least one epoxide compound selected from the group consisting of (C2-C20)alkyleneoxide substituted or unsubstituted with halogen, (C1-C20)alkyloxy, (C6-C20)aryloxy, or (C6-C20)ar(C1-C20)alkyl(aralkyl)oxy; (C4-C20)cycloalkyleneoxide substituted or unsubstituted with halogen, (C1-C20)alkyloxy, (C6-C20)aryloxy or (C6-C20)ar(C1-C20)alkyl(aralkyl)oxy; and (C8-C20)styreneoxide substituted or unsubstituted with halogen, (C1-C20)alkyloxy, (C6-C20)aryloxy, (C6-C20)ar(C1-C20)alkyl(aralkyl)oxy, or (C1-C20)alkyl, by using a complex compound of Chemical Formula 2 below as a catalyst, in the presence of a polymer compound having a hydroxyl or carboxyl acid group at an terminal or a side chain thereof.
[In Chemical Formula 2,
M represents trivalent cobalt or trivalent chromium;
A represents an oxygen or sulfur atom;
Q represents a diradical linking two nitrogen atoms;
R 1 to R 10 independently represent hydrogen; halogen; (C1-C20)alkyl; (C1-C20)alkyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C2-C20)alkenyl; (C2-C20)alkenyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C1-C20)alkyl(C6-C20)aryl; (C1-C20)alkyl(C6-C20)aryl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C6-C20)aryl(C1-C20)alkyl; (C6-C20)aryl(C1-C20)alkyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C1-C20)alkoxy; (C6-C30)aryloxy; formyl; (C1-C20)alkylcarbonyl; (C6-C20)arylcarbonyl; or a metalloid radical of group 14 metal substituted with hydrocarbyl;
two of R 1 to R 10 may be linked to each other to form a ring;
at least one of hydrogens contained in R 1 to R 10 and Q is a proton group selected from the group consisting of Chemical Formulas a, b, and c;
X − represents independently a halide ion; HCO 3 − ; BF 4 − ; ClO 4 − ; NO 3 − ; PF 6 − ; (C6-C20)aryloxy anion; (C6-C20)aryloxy anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C1-C20)alkylcarboxyl anion; (C1-C20)alkyl carboxyl anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C6-C20)arylcarboxyl anion; (C6-C20)arylcarboxyl anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C1-C20)alkoxy anion; (C1-C20)alkoxy anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C1-C20)alkylcarbonate anion; (C1-C20)alkylcarbonate anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C6-C20)arylcarbonate anion; (C6-C20)arylcarbonate anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C1-C20)alkylsulfonate anion; (C1-C20)alkylsulfonate anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C1-C20)alkylamido anion; (C1-C20)alkylamido anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C6-C20)arylamido anion; (C6-C20)arylamido anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; (C1-C20)alkylcarbamate anion; (C1-C20)alkylcarbamate anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom; or (C6-C20)arylcarbamate anion; (C6-C20)arylcarbamate anion containing one or more of halogen atom, nitrogen atom, oxygen atom, silicon atom, sulfur atom, and phosphor atom;
Z is nitrogen or phosphor atom;
R 21 , R 22 , R 23 , R 31 , R 32 , R 33 , R 34 and R 35 independently represent (C1-C20)alkyl; (C1-C20)alkyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C2-C20)alkenyl; (C2-C20)alkenyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C1-C20)alkyl(C6-C20)aryl; (C1-C20)alkyl(C6-C20)aryl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C6-C20)aryl(C1-C20)alkyl; (C6-C20)aryl(C1-C20)alkyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; or a metalloid radical of group 14 metal substituted with hydrocarbyl; and two of R 21 , R 22 and R 23 , or two of R 31 , R 32 , R 33 , R 34 and R 35 may be linked to each other to form a ring;
R 41 , R 42 and R 43 independently represent hydrogen; (C1-C20)alkyl; (C1-C20)alkyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C2-C20)alkenyl; (C2-C20)alkenyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C1-C20)alkyl(C6-C20)aryl; (C1-C20)alkyl(C6-C20)aryl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; (C6-C20)aryl(C1-C20)alkyl; (C6-C20)aryl(C1-C20)alkyl containing one or more of halogen, nitrogen, oxygen, silicon, sulfur and phosphor; or a metalloid radical of group 14 metal substituted with hydrocarbyl; and two of R41, R42 and R43 may be linked to each other to form a ring;
X′ represents oxygen atom, sulfur atom, or N—R (here, R represents (C1-C20)alkyl);
n represents an integer obtained by adding one to the total number of proton groups contained in R 1 to R 10 and Q;
X − may coordinate M; and
nitrogen atom of imine may be decoordinated from M.]
In another general aspect, an eco-friendly poly(alkylene carbonate) resin composition for an interior sheet includes at least one selected from the group consisting of 2 to 50 parts by weight of an strength controller, 2 to 50 parts by weight of a dimensional stabilizer, 2 to 70 parts by weight of a flexibilizer, 0.1 to 30 parts by weight of an impact modifier, 5 to 30 parts by weight of a obliterating power improver, 0.1 to 200 parts by weight of a filler, 0.5 to 20 parts by weight of a foaming agent, 0.1 to 200 parts by weight of a flame retardant agent or a flameproofing agent, and 0.1 to 5 parts by weight of a lubricant by weight of a filler, based on 100 parts by weight of a poly(alkylene carbonate) resin.
Here, the eco-friendly poly(alkylene carbonate) resin for an interior sheet may be used as a transparent or opaque soft interior sheet, a transparent or opaque hard interior sheet, a flameproofing interior sheet, or a foaming interior sheet, by combination with the strength controller, the dimensional stabilizer, the flexibilizer, the impact modifier, the obliterating power improver, the filler, the foaming agent, the flame retardant agent, the flameproofing agent, or the lubricant.
A poly(alkylene carbonate) resin (Green Pol) in the eco-friendly poly(alkylene carbonate) resin composition is excellent in tensile strength and tear strength, due to structural distinctiveness of itself and good miscibility with processing additives, and is remarkably excellent in particularly transparency and a flameproofing characteristic (particularly, smoke density), as compared with competitive products. In addition, the poly(alkylene carbonate) resin (GreenPol) has a unique advantage in that the hardness thereof can be easily regulated, as compared with other common plastics, even when a small amount of the flexibilizer (softener) self-developed by SK Energy Company is used, and thus, can realize from ultra soft products to ultra hard products.
The eco-friendly poly(alkylene carbonate) resin composition for a transparent soft interior sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 2 to 70 parts by weight of the flexibilizer, and 0.1 to 5 parts by weight of the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for an opaque soft interior sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 2 to 70 parts by weight of the flexibilizer, 5 to 30 parts by weight of the obliterating power improver, 0.1 to 200 parts by weight of the lubricant, and 0.1 to 5 parts by weight of the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for a transparent hard interior sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 0.1 to 30 parts by weight of the impact modifier, and 0.1 to 5 parts by weight of the lubricant.
The eco-friendly poly(alkylene carbonate) resin composition for the flameproofing interior sheet may further include 0.1 to 200 parts by weight of the flame retardant agent or the flameproofing agent, in addition to the eco-friendly poly(alkylene carbonate) resin composition for the transparent or opaque soft interior sheet or the transparent or opaque hard interior sheet.
The eco-friendly poly(alkylene carbonate) resin composition for the foaming interior sheet includes 2 to 50 parts by weight of the strength controller, 2 to 50 parts by weight of the dimensional stabilizer, 2 to 70 parts by weight of the flexibilizer, 5 to 30 parts by weight of the obliterating power improver, 0 to 200 parts by weight of the filler, 0.5 to 20 parts by weight of the foaming agent, and 0.1 to 5 parts by weight of the lubricant.
In another general aspect, an eco-friendly poly(alkylene carbonate) resin composition for a tarpaulin includes at least one selected from the group consisting of 2 to 50 parts by weight of an strength controller, 2 to 100 parts by weight of a flexibilizer, 0.1 to 30 parts by weight of an impact modifier, 0.1 to 200 parts by weight of a filler, 0.1 to 5 parts by weight of a lubricant, and 0.1 to 20 parts by weight of a dye, based on 100 parts by weight of a poly(alkylene carbonate) resin.
Here, the eco-friendly poly(alkylene carbonate) resin composition for a tarpaulin may be used as a transparent or opaque soft tarpaulin or a transparent or opaque hard tarpaulin, by combination with 2 to 50 parts by weight of the strength controller, 2 to 100 parts by weight of the flexibilizer, 0.1 to 30 parts by weight of the impact modifier, 0.1 to 200 parts by weight of the filler, 0.1 to 5 parts by weight of the lubricant, or the dye.
A poly(alkylene carbonate) resin (Green Pol) in the eco-friendly poly(alkylene carbonate) resin composition is excellent in tensile strength and abrasive strength, due to structural distinctiveness of itself and good miscibility with processing additives. In addition, the poly(alkylene carbonate) resin GreenPol) has advantages in that the hardness thereof can be easily regulated even with a small amount of the flexibilizer developed by SK Energy Company and scheduled to be filed as a patent application, and adhesive strength with fabrics is very excellent.
The eco-friendly poly(alkylene carbonate) resin composition for the transparent soft tarpaulin includes 2 to 50 parts by weight of the strength controller, 2 to 100 parts by weight of the flexibilizer, 0.1 to 5 parts by weight of the lubricant, and 0.1 to 20 parts by weight of the dye, based on 100 parts by weight of a poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the opaque soft tarpaulin includes 2 to 50 parts by weight of the strength controller, 2 to 100 parts by weight of the flexibilizer, 0.1 to 200 parts by weight of the filler, 0.1 to 5 parts by weight of the lubricant, and 0.1 to 20 parts by weight of the dye, based on 100 parts by weight of a poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the transparent hard tarpaulin includes 2 to 50 parts by weight of the strength controller, 0.1 to 30 parts by weight of the impact modifier, 0.1 to 5 parts by weight of the lubricant, and 0.1 to 20 parts by weight of the dye, based on 100 parts by weight of a poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the opaque hard tarpaulin includes 2 to 50 parts by weight of the strength controller, 0.1 to 30 parts by weight of the impact modifier, 0.1 to 200 parts by weight of the filler, 0.1 to 5 parts by weight of the lubricant, and 0.1 to 20 parts by weight of the dye, based on 100 parts by weight of a poly(alkylene carbonate) resin.
In another general aspect, an eco-friendly poly(alkylene carbonate) resin composition for a packaging wrap includes at least one selected from the group consisting of 0.1 to 30 parts by weight of an strength controller, 2 to 80 parts by weight of a flexibilizer, 0.1 to 5 parts by weight of a flameproofing agent, and 0.1 to 30 parts by weight of a lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
A poly(alkylene carbonate) resin (Green Pol) in the eco-friendly poly(alkylene carbonate) resin composition is distinctly differentiated from the common plastics in view of adhesive property, elongation (stretching property), transparency, and oxygen and moisture barrier property, due to structural distinctiveness thereof.
In another general aspect, an eco-friendly poly(alkylene carbonate) resin composition for wall paper includes at least one selected from the group consisting of 2 to 100 parts by weight of a flexibilizer, 30 to 300 parts by weight of a filler, 30 to 300 parts by weight of a flame retardant agent or a flameproofing agent, 5 to 30 parts by weight of a obliterating power improver, 0.5 to 10 parts by weight of a foaming agent, and 0.1 to 10 parts by weight of a lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
Here, the eco-friendly poly(alkylene carbonate) resin composition for wall paper may be used as a foaming wall paper or a flameproofing (flame retardant) wall paper, by combination with the flexibilizer, the filler, the flame retardant agent or the flameproofing agent, the obliterating power improver, the foaming agent, or the lubricant.
A poly(alkylene carbonate) resin (Green Pol) in the eco-friendly poly(alkylene carbonate) resin composition is excellent in printability, tensile strength, elongation (stretching property), due to structural distinctiveness of itself and good miscibility with processing additives, and is excellent in foaming property, cost reduction, embossing property, acquisition of environment mark certification (due to excellent smoke density), and flameproofing property, due to good miscibility with the filler (calcium carbonate).
The eco-friendly poly(alkylene carbonate) resin composition for the foaming wall paper includes 2 to 100 parts by weight of the flexibilizer, 30 to 300 parts by weight of the filler, 5 to 30 parts by weight of the obliterating power improver, 0.5 to 10 parts by weight of the foaming agent, and 0.1 to 10 parts by weight of the lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the flameproofing (flame retardant) wall paper includes 2 to 100 parts by weight of the flexibilizer, 30 to 300 parts by weight of the filler, 30 to 300 parts by weight of the flame retardant agent or the flameproofing agent, 5 to 30 parts by weight of the obliterating power improver, 0.5 to 10 parts by weight of the foaming agent, and 0.1 to 10 parts by weight of the lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
In another general aspect, an eco-friendly poly(alkylene carbonate) resin composition for an artificial leather includes at least one selected from the group consisting of 2 to 100 parts by weight of a flexibilizer, 0.5 to 50 parts by weight of an elasticity provider, 30 to 300 parts by weight of a filler, 0.5 to 30 parts by weight of a foaming agent, 30 to 300 parts by weight of a flame retardant agent or a flameproofing agent, 5 to 30 parts by weight of a obliterating power improver, 0.1 to 20 parts by weight of a dye, and 0.1 to 10 parts by weight of a lubricant, based on 100 parts by weight of a poly(alkylene carbonate) resin.
Here, the eco-friendly poly(alkylene carbonate) resin composition for an artificial leather may be used as a foaming or nonfoaming artificial leather or a flameproofing foaming or nonfoaming artificial leather, by combination with the flexibilizer, the elasticity provider, the filler, the foaming agent, the flame retardant agent or the flameproofing agent, the obliterating power improver, the dye, or the lubricant.
A poly(alkylene carbonate) resin (Green Pol) in the eco-friendly poly(alkylene carbonate) resin composition is excellent in printability, tensile strength, elongation (stretching property), due to structural distinctiveness of itself and excellent miscibility with processing additives. In addition, the poly(alkylene carbonate) resin (GreenPol) has advantages in that the hardness thereof can be easily regulated even with a small amount of the flexibilizer developed by SK Energy Company and scheduled to be filed as a patent application, and environment mark certification can be acquired due to excellent smoke density.
The eco-friendly poly(alkylene carbonate) resin composition for the foaming artificial leather includes 2 to 100 parts by weight of the flexibilizer, 0.5 to 50 parts by weight of the elasticity provider, 30 to 300 parts by weight of the filler, 0.5 to 30 parts by weight of the foaming agent, 30 to 300 parts by weight of the flame retardant agent or the flameproofing agent, 5 to 30 parts by weight of the obliterating power improver, 0.1 to 20 parts by weight of the dye, and 0.1 to 10 parts by weight of the lubricant, based on 100 parts by weight of the poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the nonfoaming artificial leather includes 2 to 100 parts by weight of the flexibilizer, 0.5 to 50 parts by weight of the elasticity provider, 30 to 300 parts by weight of the filler, 0.5 to 30 parts by weight of the foaming agent, 30 to 300 parts by weight of the flame retardant agent or the flameproofing agent, 5 to 30 parts by weight of the obliterating power improver, 0.1 to 20 parts by weight of the dye, and 0.1 to 10 parts by weight of the lubricant, based on 100 parts by weight of the poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the flameproofing foaming artificial leather includes 2 to 100 parts by weight of the flexibilizer, 0.5 to 50 parts by weight of the elasticity provider, 30 to 300 parts by weight of the filler, 0.5 to 30 parts by weight of the foaming agent, 30 to 300 parts by weight of the flame retardant agent or the flameproofing agent, 5 to 30 parts by weight of the obliterating power improver, 0.1 to 20 parts by weight of the dye, and 0.1 to 10 parts by weight of the lubricant, based on 100 parts by weight of the poly(alkylene carbonate) resin.
The eco-friendly poly(alkylene carbonate) resin composition for the flameproofing nonfoaming artificial leather includes 2 to 100 parts by weight of the flexibilizer, 0.5 to 50 parts by weight of the elasticity provider, 30 to 300 parts by weight of the filler, 0.5 to 30 parts by weight of the foaming agent, 30 to 300 parts by weight of the flame retardant agent or the flameproofing agent, 5 to 30 parts by weight of the obliterating power improver, 0.1 to 20 parts by weight of the dye, and 0.1 to 10 parts by weight of the lubricant, based on 100 parts by weight of the poly(alkylene carbonate) resin.
The above-mentioned eco-friendly poly(alkylene carbonate) resin composition may be prepared by an extrusion method as well as a calender method. The calender method exhibits excellence in view of productivity by four to five times as compared with the extrusion method of the related art, and can be performed at a lower temperature. The eco-friendly poly(alkylene carbonate) resin composition has lower specific gravity than polyvinyl chloride resin based materials, thereby reducing the manufacturing costs.
In addition, the eco-friendly poly(alkylene carbonate) resin composition has excellent elongation, as compared with polypropylene (PP) and polyethylene terephthalate glycol (PET-G), which are alternatives for the polyvinyl chloride resin. The above elongation is improved by three to four times as compared with that of the polyvinyl chloride resin. The eco-friendly poly(alkylene carbonate) resin composition for the decorative sheet according to the present invention exhibits very favorable physical properties in a process where it is stretched and attached on wooden materials or iron plates, and the process can be performed at a low temperature, such as room temperature to 50° C. This enables the eco-friendly poly(alkylene carbonate) resin composition for the packaging wrap to have appropriate elongation (stretching property).
In addition, when the eco-friendly poly(alkylene carbonate) resin composition for the packaging wrap or the wall paper is applied for use in foaming, it exhibits very excellent tensile strength and elongation, and it is excellent in improvement of durability and easiness of post processing.
DETAILED DESCRIPTION OF EMBODIMENTS
Hereinafter, the present invention will be described in detail by examples.
The following examples are for merely exemplifying the present invention, and therefore, the scope of the present invention is not limited to the following examples.
(Evaluation on Physical Property)
1. Tensile strength/Elongation was measured according to ASTM D638.
2. Tear strength was measured according to ASTM D1004.
3. Smoke density was measured according to ASTM E662.
4. Dimensional stability: Each sheet specimen (200×20 mm) was kept within a dry oven at 80° C. for one week, and then it was measured whether length variations thereof are within ±4%.
5. Cold resistant property: Five sheet specimens (150×20 mm) were kept within a chamber at −30° C. for 4 hours, and then evaluation was performed on the sheet specimens by Folding test (After each specimen installed at the catching unit was folded and then unfolded, a degree at which the specimen is split or broken was evaluated.)
(Evaluation: Fail when Two or More Specimens are Broken)
6. Whiteness index: Whiteness index was measured by a color meter.
7. Calender processability and workability: blendability/compoundability, processing temperature, Roll workability, and a degree at which molten materials are stained on a roll, were measured.
(Evaluation: 1. very inferior, 2. inferior, 3. good, 4. excellent, 5. most excellent)
8. Post processing workability: Workability about printing, embossing, laminating, or surface treatment, was measured.
(Evaluation: 1. very inferior, 2. inferior, 3. good, 4. excellent, 5. most excellent)
9. Transparency was measured by using a haze meter.
Example 1
100 parts by weight of a poly(propylene carbonate) resin (Green Pol, SK Energy Company), 5 parts by weight of an strength controller and dimensional stabilizer (PA828, LG Chemistry), 5 parts by weight of a flexibilizer (DAIFATTY-101, Japan), 15 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), and 2 parts by weight of a lubricant (stearic acid, and dioctylterephthalate by Eastman Company in USA) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 140° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, thereby producing a decorative sheet finished product.
Physical properties of the produced opaque soft eco-friendly poly(propylene carbonate) decorative sheet product were measured, and then tabulated in to Table 1.
Example 2
A product was produced by performing the same method as Example 1 except that the flexibilizer was not used, and physical property results thereof were tabulated in Table. 1
TABLE 1
Polyvinyl
chloride
Physical Property
Example 1
Example 2
(for membrane)
Tensile
4.5~5.0
6.0~6.4
1.9~2.0
strength (kgf/mm 2 )
Elongation (%)
570~650
400~450
200~300
Tear
2.0~2.3
3.6~4.0
0.8~1.1
Strength (kgf/mm)
Printability
Most excellent
Most excellent
Excellent
Flameproofing
1~10
1~10
1000~1100
Property
(Smoke Density)
Example 3
100 parts by weight of a poly(propylene carbonate) resin (Green Pol, SK Energy Company), 5 parts by weight of an strength controller and 1 parts by weight of a lubricant (dioctylterephthalate by Eastman Company in USA) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 140° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, and then adhered to a glass fiber, followed by print, primer, and surface treatment processes, thereby producing a decorative sheet finished product.
Physical properties of the produced transparent hard eco-friendly poly(propylene carbonate) interior sheet product were measured, and then tabulated in Table 2.
Example 4
A product was produced by performing the same method as Example 3 except that an impact modifier was not used and 20 parts by weight of a flexibilizer was used, and physical property results thereof were tabulated in Table. 2
TABLE 2
polyvinyl
chloride
(Plasticizer
Content, 60
Physical
parts by
Property
Example 3
Example 4
weight)
Hardness (Shore
90~96
40~45
50~60
A)
Transparency (Opacity)
<3
<3
<5
Flameproofing
1~10
1~10
1000~1300
Property
(Smoke Density)
Environment
Possible
Possible
Impossible
Mark
Certification
Example 5
100 parts by weight of a poly(propylene carbonate) resin (Green Pol, SK Energy Company), 150 parts by weight of a filler (Omya-10, Omya Korea Company), 15 parts by weight of a obliteraring power improver (KA100, Cosmo Chemistry), 20 parts by weight of a flexibilizer (DAIFATTY-101, Japan), 3 weight of a foaming agent (AC1000, KumYang Company), and 2 parts by weight of a lubricant (stearic acid, and dioctylterephthalate) were put in a Henschel mixer, and then dry blended for 30 to 40 minutes. The dry blended mixture was put into a compounding extruder at 110° C. to be sheeted. This was prepared into a foaming sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, and then was adhered to a raw paper, followed by foaming, printing, and embossing processes, thereby producing a finished product.
Physical properties of the produced eco-friendly poly(propylene carbonate) wall paper product were measured, and then tabulated in Table 3.
Example 6
100 parts by weight of a poly(propylene carbonate) resin (Green Pol, SK Energy Company), 120 parts by weight of a filler (Omya-5T, Omya Korea Company), 5 parts by weight of an elasticity provider (Soarblen, Uni trading corporation), 20 parts by weight of a flexibilizer (DAIFATTY-101, Japan), 3 weight of a foaming agent (AC3000, KumYang Company), and 2 parts by weight of a lubricant (stearic acid, and dioctylterephthalate) were put in a Henschel mixer, and then dry blended for 30 to 40 minutes. The dry blended mixture was put into a compounding extruder at 110° C. to be sheeted. This was prepared into a foaming sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, and then was adhered to a raw fabric, followed by foaming, printing, embossing, and surface treatment processes, thereby producing a finished product.
Physical properties of the produced eco-friendly poly(propylene carbonate) artificial leather product were measured, and then tabulated in Table 3.
TABLE 3
polyvinyl
polyvinyl
chloride
chloride
Physical
(Wall
(Artificial
Property
Example 5
Paper)
Example 6
Leather)
Foaming
Opened cell
Opened cell
Closed
Closed cell
Physical
(Irregular
(Irregular
cell (≧Fine
(≧Fine
Property
sphere), <2
sphere), <2
sphere),
sphere), 2.5
(Cell
times
times
2.5 to 3
to 3 times
state/
times
Magnification)
Elongation(%)
<100
<10
100~130
<30
Flameproofing
1~10
1000~1100
1~10
1000~1200
Property
(Smoke
Density)
Environment
Possible
Impossible
Possible
Impossible
Mark
Certification
Example 7
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weight of an strength controller (LLDPE, SK Company), 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 0.1 parts by weight of a compatibilizer (EM200, Honam Petrochemical Company), 20 parts by weight of a filler (Omya-2T, Omya Korea), and 1 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 150° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 8 to 18 and Comparative Examples 1 and 2
Examples 8 to 12 were performed by the same method as Example 1 except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight for the examples, respectively. Examples 13 to 18 were performed by the same method as Example 7 except that SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for the examples, respectively. Comparative examples 1 and 2 were performed by the same method as Example 7 except that the strength controller and the flexibilizer were not used, respectively.
TABLE 4
Example
Comparative
Comparative
7
8
9
10
11
12
13
14
15
16
17
18
example 1
example 2
Tensile
110
140
155
180
220
250
195
182
165
150
132
100
30
210
strength (kgf/mm 2 )
Tear
45
60
70
95
110
130
94
87
80
68
60
52
12
105
Strength (kgf/cm 2 )
Elongation (%)
700
680
530
480
350
300
420
490
540
620
750
>800
>800
330
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
X
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
X
◯
Property (−30° C.)
Calender
3
4
4
4
5
5
4
4
4
4
4
3
2
4
Processability
& Workability
Post Processing
3
4
4
4
4
4
4
4
4
4
4
4
2
4
Workability
Smoke Density
30
33
35
40
50
60
<30
<30
<30
<30
<30
<30
<20
33
Examples 19 to 30
Examples 19 to 24 were performed by the same methods as Examples 13 to 18, respectively, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer. Examples 25 to 30 were performed by the same methods as Examples 13 to 18, respectively, except that acrylate (PA828, LG Chemical) was used as the flexibilizer.
TABLE 5
Example
19
20
21
22
23
24
25
26
27
28
29
30
Tensile
190
176
155
144
120
95
184
170
148
135
114
93
strength (kgf/cm 2 )
Tear
82
75
70
57
53
45
79
72
65
52
45
39
Strength (kgf/cm 2 )
Elongation (%)
450
500
530
650
>800
>800
440
490
540
640
>800
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
Property (−30° C.)
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&
Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Examples 31 to 46
Examples 31 to 46 were performed by the same method as Example 7, except that TU100D by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 31 to 34, respectively; BP402 by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 35 to 38, respectively; EV600 by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 39 to 42, respectively; and EM200 by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 43 to 46, respectively. Comparative example 3 was performed by the same method as Example 7 except that the compatibilizer was not used.
TABLE 6
Example
Comparative
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
example 3
Tensile
152
170
200
225
145
167
190
210
154
173
205
227
155
173
210
230
135
strength
(kgf/cm 2 )
Tear
68
80
95
110
64
77
92
106
68
83
95
110
70
83
98
115
52
Strength
(kgf/cm 2 )
Elongation (%)
540
640
650
750
550
640
670
750
540
630
700
>800
530
630
670
750
460
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Resistant
Property (−30° C.)
Calender
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Density
Examples 47 to 58
Examples 47 to 58 were performed by the same method as Example 7, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 47 to 50, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 51 to 54, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 55 to 58, respectively. Comparative example 4 was performed by the same method as Example 7 except that the compatibilizer was not used.
TABLE 7
Example
Comparative
47
48
49
50
51
52
53
54
55
56
57
58
example 4
Tensile
160
152
105
55
155
148
90
50
154
144
92
60
190
strength
(kgf/cm 2 )
Tear Strength
72
70
55
30
70
67
50
26
68
66
50
28
88
(kgf/cm 2 )
Elongation (%)
500
580
640
700
530
600
650
730
530
600
650
700
330
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
◯
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
◯
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
4
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke Density
<35
<30
<30
<30
<35
<30
<30
<30
<35
<30
<30
<30
<35
Examples 59 to 70
Examples 59 to 62 were performed by the same methods as Examples 47 to 50, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 63 to 66 were performed by the same methods as Examples 47 to 50, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 67 to 70 were performed by the same methods as Examples 47 to 50, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 8
Example
59
60
61
62
63
64
65
66
67
68
69
70
Tensile
152
140
88
54
144
120
84
41
140
118
76
40
strength
(kgf/cm 2 )
Tear Strength
69
60
46
26
61
50
39
26
60
48
37
26
(kgf/cm 2 )
Elongation (%)
550
630
680
740
430
510
580
650
450
530
610
670
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke Density
<35
<30
<30
<30
<35
<30
<30
<30
<35
<30
<30
<30
Examples 71 to 80 and Comparative Examples 5 and 6
Examples 71 to 80 were performed by the same method as Example 7, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 71 to 75, respectively; and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 76 to 80, respectively. Comparative examples 5 and 6 were performed by the same method as Example 7 except that the obliterating power improver and the lubricant were not used for the comparative examples, respectively.
TABLE 9
Comparative
Exam-
Exam-
Exam-
Exam-
Exam-
example 5
ple 71
ple 72
ple 73
ple 74
ple 75
Whiteness
40
60
>80
>80
>80
>80
TABLE 10
Example
Comparative
example 6
Example 76
Example 77
Example 78
Example 79
Example 80
Calender
2
4
4
4
4
2
Processability&Workability
Post
2
4
4
4
4
2
Processing
Workability
Example 81
Example 81 was performed by the same method as Example 7 except that Random Polypropylene by SK Innovation Company was used as the strength controller.
Examples 82 to 92
Examples 82 to 92 were performed by the same method as Example 81, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight for Examples 82 to 86, respectively; and SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 87 to 92, respectively.
TABLE 11
Example
81
82
83
84
85
86
87
88
89
90
91
92
Tensile
115
155
180
205
234
265
230
205
196
172
152
122
strength (kgf/cm 2 )
Tear
47
70
85
97
119
132
112
98
86
77
68
57
Strength (kgf/cm 2 )
Elongation (%)
680
620
530
420
330
270
400
490
550
680
>800
>800
Dimensional
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
3
4
4
4
5
5
4
4
4
4
4
3
Processability&Workability
Post Processing
3
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
30
33
35
40
50
60
<30
<30
<30
<30
<30
<30
Examples 93 to 104
Examples 93 to 98 were performed by the same methods as Examples 87 to 92, respectively, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer. Examples 99 to 104 were performed by the same methods as Examples 87 to 92, respectively, except that acrylate (PA828, LG Chemical) was used as the flexibilizer.
TABLE 12
Example
93
94
95
96
97
98
99
100
101
102
103
104
Tensile
200
186
180
164
142
110
210
196
185
171
150
118
strength (kgf/cm 2 )
Tear
97
90
85
78
68
55
107
97
87
80
70
56
Strength (kgf/cm 2 )
Elongation (%)
400
470
530
660
>800
>800
410
490
570
700
>800
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Examples 105 to 120
Examples 105 to 120 were performed by the same method as Example 81, except that TU100D by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 105 to 108, respectively; BP402 by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 109 to 112, respectively; EV600 by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 113 to 116, respectively; and EM200 by Honam Petrochemical Company was used as the compatibilizer and controlled in 0.1, 0.5, 1, and 5 parts by weight for Examples 117 to 120, respectively.
TABLE 13
Example
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
Tensile
173
190
206
218
180
197
210
228
174
192
208
215
177
195
209
224
strength
(kgf/cm 2 )
Tear
80
91
100
112
85
98
107
115
80
93
99
112
88
95
107
112
Strength
(kgf/cm 2 )
Elongation
460
530
620
690
480
540
620
700
500
590
670
750
490
550
640
730
(%)
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Resistant
Property
(−30° C.)
Calender
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Density
Examples 121 to 132
Examples 121 to 132 were performed by the same method as Example 81, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 121 to 124, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 125 to 128, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 129 to 132, respectively.
TABLE 14
Example
121
122
123
124
125
126
127
128
129
130
131
132
Tensile
188
170
143
107
180
164
139
92
174
160
135
88
strength
(kgf/cm 2 )
Tear Strength
87
80
68
52
85
77
64
48
77
69
60
46
(kgf/cm 2 )
Elongation (%)
520
580
640
690
530
620
650
680
520
580
610
660
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke Density
<35
<30
<30
<30
35
<30
<30
<30
<35
<30
<30
<30
Examples 133 to 144
Examples 133 to 136 were performed by the same methods as Examples 121 to 124, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 137 to 140 were performed by the same methods as Examples 121 to 124, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 141 to 144 were performed by the same methods as Examples 121 to 124, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 15
Example
133
134
135
136
137
138
139
140
141
142
143
144
Tensile
170
155
128
80
170
154
130
75
166
149
130
72
strength
(kgf/cm 2 )
Tear Strength
73
63
58
38
73
60
52
38
70
59
50
35
(kgf/cm 2 )
Elongation (%)
540
600
650
700
500
550
600
660
520
590
620
680
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke Density
<35
<30
<30
<30
<35
<30
<30
<30
<35
<30
<30
<30
Examples 145 to 154
Examples 145 to 154 were performed by the same method as Example 81, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 145 to 149, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 150 to 154.
TABLE 16
Example
145
146
147
148
149
Whiteness
60
>80
>80
>80
>80
TABLE 17
Example
150
151
152
153
154
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
Example 155
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weight of an strength controller (polylactic acid, SK Innovation Company), 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 20 parts by weight of a filler (Omya-2T, Omya Korea Company), and 2 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 160° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 156 to 166
Examples 156 to 166 were performed by the same method as Example 155, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight for Examples 156 to 160, respectively; and SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 161 to 166, respectively.
TABLE 18
Example
155
156
157
158
159
160
161
162
163
164
165
166
Tensile
110
140
155
180
220
255
200
192
172
158
130
110
strength (kgf/cm 2 )
Tear
45
60
70
91
106
124
98
86
75
68
56
47
Strength (kgf/cm 2 )
Elongation (%)
700
580
430
380
250
180
280
330
400
520
660
750
Dimensional
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
3
4
4
4
4
2
4
4
4
4
4
3
Processability&Workability
Post Processing
3
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
Examples 167 to 178
Examples 167 to 178 were performed by the same method as Example 155, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 for Examples 167 to 172, respectively; and acrylate (PA828, LG Company) was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 for Examples 173 to 178, respectively.
TABLE 19
Example
167
168
169
170
171
172
173
174
175
176
177
178
Tensile
194
177
155
134
118
102
202
188
170
158
134
112
strength (kgf/cm 2 )
Tear
83
77
70
61
52
47
100
83
73
66
58
45
Strength (kgf/cm 2 )
Elongation (%)
270
350
430
550
680
>800
260
310
390
480
640
770
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
Examples 179 to 190
Examples 179 to 190 were performed by the same method as Example 81, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 179 to 182, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 183 to 186, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 187 to 190, respectively.
TABLE 20
Example
179
180
181
182
183
184
185
186
187
188
189
190
Tensile
160
146
129
70
155
142
118
60
152
138
113
58
strength
(kgf/cm 2 )
Tear Strength
76
66
58
35
70
62
55
32
69
60
51
30
(kgf/cm 2 )
Elongation (%)
480
550
620
710
530
590
660
750
490
560
650
730
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke Density
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
Examples 191 to 202
Examples 191 to 194 were performed by the same methods as Examples 179 to 182, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 195 to 198 were performed by the same methods as Examples 179 to 182, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 199 to 202 were performed by the same methods as Examples 179 to 182, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 21
Example
191
192
193
194
195
196
197
198
199
200
201
202
Tensile
148
130
107
50
140
127
104
50
135
120
98
48
strength
(kgf/cm 2 )
Tear Strength
66
58
47
23
59
51
45
22
55
46
40
22
(kgf/cm 2 )
Elongation (%)
500
550
660
740
410
530
620
700
430
530
650
750
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke Density
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
<30
Examples 203 to 212
Examples 203 to 212 were performed by the same method as Example 155, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 203 to 207, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 208 to 212.
TABLE 22
Example
203
204
205
206
207
Whiteness
60
>80
>80
>80
>80
TABLE 23
Example
208
209
210
211
212
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
Example 213
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weight of pellet type modified polyester by BASF Company as an strength controller, 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 20 parts by weight of a filler (Omya-2T, Omya Korea), and 2 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 120° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 214 to 224
Examples 214 to 218 were performed by the same method as Example 1, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight, respectively, and Examples 219 to 224 were performed by the same method as Example 213, except that SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 219 to 224, respectively.
TABLE 24
Example
213
214
215
216
217
218
219
220
221
222
223
224
Tensile
137
148
160
182
207
230
218
195
177
163
151
120
strength (kgf/cm 2 )
Tear
65
71
77
89
103
117
107
95
83
71
63
54
Strength (kgf/cm 2 )
Elongation (%)
700
610
500
440
380
290
430
480
560
670
>800
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
4
4
4
4
4
4
4
4
4
4
4
3
Processability&Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
Examples 225 to 236
Examples 225 to 230 were performed by the same method as Example 213, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight, respectively, and Examples 231 to 236 were performed by the same method as Example 213 except that acrylate (PA828, LG Company) was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight, respectively.
TABLE 25
Example
225
226
227
228
229
230
231
232
233
234
235
236
Tensile
207
182
160
151
140
118
202
188
170
158
134
112
strength (kgf/cm 2 )
Tear
105
89
77
69
58
51
100
83
73
66
58
45
Strength (kgf/cm 2 )
Elongation (%)
420
450
500
620
750
>800
260
310
390
480
640
770
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<20
<20
<20
<20
<20
<20
<30
<30
<30
<30
<30
<30
Examples 237 to 248
Examples 237 to 248 were performed by the same method as Example 213, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 237 to 240, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 241 to 244, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 245 to 248, respectively.
TABLE 26
Example
237
238
239
240
241
242
243
244
245
246
247
248
Tensile
168
145
120
70
160
140
117
67
165
140
116
62
strength
(kgf/cm 2 )
Tear
79
69
56
34
77
67
55
34
77
65
55
32
Strength
(kgf/cm 2 )
Elongation (%)
510
590
630
710
520
610
680
770
520
600
660
750
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
Density
Examples 249 to 260
Examples 249 to 252 were performed by the same methods as Examples 237 to 240, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 253 to 256 were performed by the same methods as Examples 237 to 240, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 257 to 260 were performed by the same methods as Examples 237 to 240, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 27
Example
249
250
251
252
253
254
255
256
257
258
259
260
Tensile
162
136
109
55
157
128
102
51
152
121
93
44
strength
(kgf/cm 2 )
Tear
71
60
49
21
70
57
49
21
66
52
41
17
Strength
(kgf/cm 2 )
Elongation (%)
540
620
700
>800
470
550
610
690
480
540
620
700
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property (−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
<20
Density
Examples 261 to 270
Examples 261 to 270 were performed by the same method as Example 213, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 261 to 265, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 266 to 270.
TABLE 28
Example
261
262
263
264
265
Whiteness
60
>80
>80
>80
>80
TABLE 29
Example
266
267
268
269
270
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
Example 271
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weight of a liquid polymer type modified polyester by Aekyung Chemical Company as an strength controller, 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 20 parts by weight of a filler (Omya-2T, Omya Korea), and 2 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 130° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 272 to 282
Examples 272 to 276 were performed by the same method as Example 273, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight, respectively, and Examples 277 to 282 were performed by the same method as Example 273 except that SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight, respectively.
TABLE 30
Example
271
272
273
274
275
276
277
278
279
280
281
282
Tensile
144
152
165
188
215
235
215
191
170
158
146
123
strength (kgf/cm 2 )
Tear
68
72
78
91
106
120
108
94
79
70
63
51
Strength (kgf/cm 2 )
Elongation (%)
680
590
510
420
300
290
380
440
530
640
750
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property (−30° C.)
Calender
4
4
4
4
4
4
4
4
4
4
4
3
Processability&Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
Examples 283 to 294
Examples 283 to 294 were performed by the same method as Example 273, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and parts by weigh for Examples 283 to 288, respectively; and acrylate (PA828, LG Company) was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 289 to 294, respectively.
TABLE 31
Example
283
284
285
286
287
288
289
290
291
292
293
294
Tensile
210
187
165
154
142
120
213
188
168
156
141
120
strength(kgf/cm 2 )
Tear
107
92
78
70
62
51
107
93
77
69
61
49
Strength(kgf/cm 2 )
Elongation(%)
370
420
510
630
740
>800
380
430
520
640
730
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&
Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
Examples 295 to 306
Examples 295 to 306 were performed by the same method as Example 273, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 295 to 298, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 299 to 302, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples to 303 to 306, respectively.
TABLE 32
Example
295
296
297
298
299
300
301
302
303
304
305
306
Tensile
167
145
128
80
165
142
120
75
163
139
120
71
strength
(kgf/cm 2 )
Tear
78
67
58
33
78
68
57
34
75
62
53
30
Strength
(kgf/cm 2 )
Elongation(%)
500
550
630
710
510
570
660
750
490
530
610
690
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
Density
Examples 307 to 318
Examples 307 to 310 were performed by the same methods as Examples 295 to 298, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 311 to 314 were performed by the same methods as Examples 295 to 298, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 315 to 318 were performed by the same methods as Examples 295 to 298, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 33
Example
307
308
309
310
311
312
313
314
315
316
317
318
Tensile
158
133
118
65
156
130
108
65
151
122
100
61
strength
(kgf/cm 2 )
Tear
71
58
48
26
71
62
49
24
69
60
44
22
Strength
(kgf/cm 2 )
Elongation(%)
500
550
630
720
430
490
570
650
450
510
580
650
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
<25
Density
Examples 319 to 328
Examples 319 to 328 were performed by the same method as Example 273, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 319 to 323, respectively, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 324 to 318, respectively.
TABLE 34
Example
319
320
321
322
323
Whiteness
60
>80
>80
>80
>80
TABLE 35
Example
324
325
326
327
328
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
Example 329
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weigh of polymethylmethacrylate by LG Company as the strength controller, 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 20 parts by weight of a filler (Omya-2T, Omya Korea), and 1 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 160° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 330 to 340
Examples 330 to 340 were performed by the same method as Example 329, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight for Examples 330 to 334, respectively; and SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 335 to 340, respectively.
TABLE 36
Example
329
330
331
332
333
334
335
336
337
338
339
340
Tensile
180
225
250
280
325
360
295
283
264
235
207
150
strength(kgf/cm 2 )
Tear
88
117
120
137
158
175
147
131
123
107
98
71
Strength(kgf/cm 2 )
Elongation(%)
600
480
390
220
100
80
255
290
370
430
500
580
Dimensional
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
X
X
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
3
4
4
4
5
5
4
4
4
4
4
3
Processability&
Workability
Post Processing
3
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
30
<35
<35
<35
<40
<40
<35
<35
<35
<35
<35
<35
Examples 341 to 352
Examples 341 to 352 were performed by the same method as Example 329, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 for Examples 341 to 346, respectively; and acrylate (PA828, LG Company) was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 for Examples 347 to 352, respectively.
TABLE 37
Example
341
342
343
344
345
346
347
348
349
350
351
352
Tensile
293
270
250
228
195
145
280
263
239
205
188
125
strength(kgf/cm 2 )
Tear
145
128
120
104
96
70
134
117
103
96
86
58
Strength(kgf/cm 2 )
Elongation(%)
260
310
390
450
520
590
280
370
460
550
620
700
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
X
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&
Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Examples 353 to 364
Examples 353 to 364 were performed by the same method as Example 329, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 353 to 356, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 357 to 360, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 361 to 364, respectively.
TABLE 38
Example
353
354
355
356
357
358
359
360
361
362
363
364
Tensile
255
231
210
196
250
227
202
182
244
210
189
165
strength
(kgf/cm 2 )
Tear
120
98
92
88
120
113
99
92
112
96
87
74
Strength
(kgf/cm 2 )
Elongation(%)
350
440
500
570
390
470
550
620
340
410
470
530
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Density
Examples 354 to 365
Examples 365 to 368 were performed by the same methods as Examples 353 to 356, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 369 to 372 were performed by the same methods as Examples 353 to 356, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 373 to 376 were performed by the same methods as Examples 353 to 356, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 39
Example
365
366
367
368
369
370
371
372
373
374
375
376
Tensile
237
201
169
140
235
201
165
137
227
190
157
125
strength
(kgf/cm 2 )
Tear
105
93
82
69
103
92
75
65
100
88
72
60
Strength
(kgf/cm 2 )
Elongation(%)
340
380
440
520
330
390
450
510
330
370
430
490
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Density
Examples 377 to 386
Examples 377 to 386 were performed by the same method as Example 329, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 377 to 381, respectively, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 382 to 386, respectively.
TABLE 40
Example
377
378
379
380
381
Whiteness
60
>80
>80
>80
>80
TABLE 41
Example
382
383
384
385
386
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
Example 387
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weigh of ethylene vinylacetate by Samsung Total Company as the strength controller, 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 20 parts by weight of a filler (Omya-2T, Omya Korea), and 2 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 120° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 388 to 399
Examples 388 to 399 were performed by the same method as Example 387, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight for Examples 388 to 393, respectively; and SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 394 to 399, respectively.
TABLE 42
Example
388
389
390
391
392
393
394
395
396
397
398
399
Tensile
105
125
140
156
170
188
188
164
149
133
121
72
strength(kgf/cm 2 )
Tear
48
57
65
70
72
86
85
75
67
60
51
24
Strength(kgf/cm 2 )
Elongation(%)
700
620
550
490
430
400
370
440
520
600
680
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
3
4
4
4
5
5
4
4
4
4
4
3
Processability&
Workability
Post Processing
3
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<30
<35
<40
<50
<60
<75
<40
<40
<40
<40
<40
<40
Examples 400 to 411
Examples 400 to 411 were performed by the same method as Example 387, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 400 to 405, respectively; and acrylate (PA828, LG Company) was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 406 to 411, respectively.
TABLE 43
Example
400
401
402
403
404
405
406
407
408
409
410
411
Tensile
180
156
140
128
105
60
182
159
144
130
116
67
strength(kgf/cm 2 )
Tear
83
71
65
58
47
22
83
72
67
59
49
23
Strength(kgf/cm 2 )
Elongation(%)
380
460
550
670
>800
>800
370
450
520
620
710
>800
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
X
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&
Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
Examples 412 to 423
Examples 412 to 423 were performed by the same method as Example 387, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 412 to 415, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 416 to 419, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 420 to 423, respectively.
TABLE 44
Example
412
413
414
415
416
417
418
419
420
421
422
423
Tensile
147
135
112
72
140
127
102
68
144
130
107
70
strength
(kgf/cm 2 )
Tear
66
63
57
24
65
60
53
23
64
61
55
23
Strength
(kgf/cm 2 )
Elongation(%)
520
600
680
>800
550
620
750
>800
500
580
650
750
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
Density
Examples 424 to 435
Examples 424 to 427 were performed by the same methods as Examples 412 to 415, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 428 to 431 were performed by the same methods as Examples 412 to 415, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 433 to 435 were performed by the same methods as Examples 412 to 415, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 45
Example
424
425
426
427
428
429
430
431
432
433
434
435
Tensile
138
123
95
59
139
127
105
65
133
120
93
50
strength
(kgf/cm 2 )
Tear
60
57
46
20
62
59
51
21
56
50
43
18
Strength
(kgf/cm 2 )
Elongation(%)
510
590
660
770
480
550
620
700
470
530
600
680
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
<40
Density
Examples 436 to 445
Examples 436 to 445 were performed by the same method as Example 388, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 436 to 440, respectively, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 441 to 445, respectively.
TABLE 46
Example
436
437
438
439
440
Whiteness
60
>80
>80
>80
>80
TABLE 47
Example
441
442
443
444
445
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
Example 446
100 parts by weight of a poly(propylene carbonate) resin (SK Innovation Company), 5 parts by weigh of thermoplastic copolyester elastomer by LG Chemical Company as the strength controller, 5 parts by weight of a flexibilizer (DAIFATTY-101, DAIHACHI Company in Japan), 7.5 parts by weight of a obliterating power improver (KA100, Cosmo Chemistry), 20 parts by weight of a filler (Omya-2T, Omya Korea), and 2 part by weight of a lubricant (stearic acid, OCI) were put in a Henschel mixer, and then dry blended for 20 minutes. The dry blended mixture was put into a compounding extruder at 150° C. to be pelletized. This was prepared into a sheet semi-finished product through a compounding process (mixing rolls and warming rolls) and a calender process, followed by print, primer, and surface treatment processes, and a laminating process, thereby producing a decorative sheet finished product.
Examples 447 to 457
Examples 447 to 457 were performed by the same method as Example 446, except that the strength controller was controlled in 10, 20, 50, 75, and 100 parts by weight for Examples 447 to 451, respectively; and SKflex by SK Innovation Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 452 to 457, respectively.
TABLE 48
Example
446
447
448
449
450
451
452
453
454
455
456
457
Tensile
120
150
175
205
234
265
218
197
181
166
145
110
strength(kgf/cm 2 )
Tear
55
69
82
97
119
132
115
97
85
74
67
57
Strength(kgf/cm 2 )
Elongation(%)
680
610
500
410
340
270
370
430
490
550
620
720
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
3
4
4
4
5
5
4
4
4
4
4
3
Processability&
Workability
Post Processing
3
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke Density
<30
<30
<35
<40
<40
<40
<30
<30
<30
<30
<30
<30
Examples 458 to 469
Examples 458 to 469 were performed by the same method as Example 446, except that DAIFATTY-101 by DAIHACHI Company was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 for Examples 458 to 463, respectively; and acrylate (PA828, LG Chemical Company) parts by weight was used as the flexibilizer and controlled in 1, 2.5, 5, 10, 20, and 50 parts by weight for Examples 464 to 469, respectively.
TABLE 49
Example
458
459
460
461
462
463
464
465
466
467
468
469
Tensile
215
192
175
160
137
105
216
195
177
162
140
107
strength(kgf/cm 2 )
Tear
114
97
82
73
62
53
113
95
83
75
65
55
Strength(kgf/cm 2 )
Elongation(%)
380
440
500
580
670
>800
370
440
510
570
640
750
Dimensional
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Stability
(±4%, 80° C.)
Cold Resistant
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
Property(−30° C.)
Calender
4
4
4
4
4
3
4
4
4
4
4
3
Processability&
Workability
Post Processing
4
4
4
4
4
4
4
4
4
4
4
4
Workability
Smoke
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
<35
Density
Examples 470 to 481
Examples 470 to 481 were performed by the same method as Example 446, except that Omya-2 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 470 to 473, respectively; Omya-2T by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 474 to 477, respectively; and Omya-5 by Omya Korea Company was used as the filler and controlled in 20, 50, 100, and 200 parts by weight for Examples 478 to 481, respectively.
TABLE 50
Example
470
471
472
473
474
475
476
477
478
479
480
481
Tensile
177
162
141
94
175
158
130
86
171
155
129
80
strength
(kgf/cm 2 )
Tear
83
73
63
43
82
73
59
42
75
68
57
35
Strength
(kgf/cm 2 )
Elongation(%)
470
550
610
700
500
570
640
700
460
520
590
660
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<35
<35
<30
<30
<35
<35
<30
<30
<35
<35
<30
<30
Density
Examples 482 to 493
Examples 482 to 485 were performed by the same methods as Examples 470 to 473, respectively, except that Omya-5T by Omya Korea Company was used as the filler; Examples 486 to 489 were performed by the same methods as Examples 470 to 473, respectively, except that Omya-10 by Omya Korea Company was used as the filler; and Examples 490 to 493 were performed by the same methods as Examples 470 to 473, respectively, except that Omya-10T by Omya Korea Company was used as the filler.
TABLE 51
Example
482
483
484
485
486
487
488
489
490
491
492
493
Tensile
165
144
115
69
160
143
113
69
148
121
100
52
strength
(kgf/cm 2 )
Tear
70
62
53
30
70
61
52
28
65
53
46
22
Strength
(kgf/cm 2 )
Elongation(%)
420
490
570
640
400
470
550
630
380
460
510
600
Dimensional
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Stability
(±4%, 80° C.)
Cold
◯
◯
◯
X
◯
◯
◯
X
◯
◯
◯
X
Resistant
Property(−30° C.)
Calender
4
5
5
5
4
5
5
5
4
5
5
5
Processability
&Workability
Post
4
4
4
4
4
4
4
4
4
4
4
4
Processing
Workability
Smoke
<35
<35
<30
<30
<35
<35
<30
<30
<35
<35
<30
<30
Density
Examples 494 to 503
Examples 494 to 503 were performed by the same method as Example 446, except that the obliterating power improver was controlled in 5, 7.5, 10, 20, and 30 parts by weight for Examples 494 to 498, and the lubricant was controlled in 0.1, 0.5, 1, 2, and 5 parts by weight for Examples 499 to 503.
TABLE 52
Example
494
495
496
497
498
Whiteness
60
>80
>80
>80
>80
TABLE 53
Example
499
500
501
502
503
Calender
4
4
4
4
2
Processability
&Workability
Post
4
4
4
4
2
Processing
Workability
As described above, products made of the eco-friendly poly(propylene carbonate) resin composition according to the present invention never generate harmful gases and dioxine at the time of combustion, which are big weaknesses of polyvinyl chloride materials. In addition, the present invention has a smoke density corresponding to about 1/600 of that of the polyvinyl chloride resin, and thus exhibits excellent flameproofing property, thereby never generating any harmful gases during processing or the use of products. Furthermore, the present invention can efficiently utilize carbon dioxide, which is a major contributor to global warming, and can remarkably improve physical properties, such as flexibility, strength, stretching property, and the like, above the level of the existing polyvinyl chloride resin, even without using phthalate based plasticizers and stabilizers, which are processing additives harmful to the human body.
Furthermore, the present invention is not easily broken in the winter time nor requires any post processing treatment, such as printing, surface treatment, and the like, thereby improving economic feasibility, by applying a calender processing method allowing mass production, rather than an extrusion processing method, which is regarded as the biggest disadvantage of alternatives for the existing polyvinyl chloride. | Provided is a resin composition for a sheet to an eco-friendly poly(alkylene carbonate) resin composition containing a poly(alkylene carbonate) resin developed by efficiently utilizing carbon dioxide, which is a major contributor to global warming, as a main material, and including an strength controller, a flexibilizer and a filler. The present invention can solve problems related to environment harmfulness of the existing polyvinyl chloride resin products and have excellent flameproofing property and stretching property. In addition, the present invention can employ a calender processing method, which allows mass production and overcome a small production type extrusion processing method, which is regarded as the biggest disadvantage of thermoplastics emerging as alternatives for the existing polyvinyl chloride products. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 USC 119(e) to U.S. App. No. 61/466,425, by Sami Mustafa et al., filed on Mar. 22, 2011, entitled CREATING THERMAL UNIFORMITY IN HEATED PIPING AND WELDMENT SYSTEMS, the entire contents being hereby incorporated by reference in its entirety
BACKGROUND
1. Technical Field
Embodiments of the invention relate generally to a heating circuit, and more specifically, incorporating a thermally conductive substrate between the heating circuit and a target heating surface.
2. Prior Art
Piping and weldment systems that must operate at higher than ambient temperatures are typically heated using some sort of electrical resistance heater circuit. These circuits are held in close proximity to the target surfaces, and are typically insulated using some material wrapped around the outside, such as silicone rubber or fiberglass. In industrial applications, this insulation material serves several purposes including physical protection of the heater circuit from the environment, improving electrical and thermal efficiency by reducing thermal losses to the environment, increasing heater circuit life by reducing the chance of over-temperature and failure of the electrical resistance material, and improving personnel safety by reducing the touch temperature on the outside surface of the heated system.
Certain materials with low thermal K factors used as insulation will improve the above effects, but heat losses and thermal loading of the piping system and the components included in the system will effect the thermal uniformity from one point in the system to another, and unless the insulation is “perfect,” it alone is insufficient to provide the thermal uniformity across the system that is required in the semiconductor industry. The difference from high to low temperature across a system becomes worse as the operating temperature set point increases. Additionally, lack of thermal uniformity is compounded by the imperfection of the heater resistance element due to it's inherent hot and cold spots.
Electrical resistance heaters utilize a heat sink to be closely engaged with the heater surface for proper operation and longest service life. If the heater is allowed to operate in “open air,” it can overheat and fail much more quickly than if it is in intimate thermal contact with a heat sink. This accelerated failure mechanism becomes more prevalent as the operating temperature set point increases, especially as the thermal limits of the materials employed in the assembly are approached.
In high tech industries such as the semiconductor manufacturing sector, much finer uniformity is often required, with typical expectations on the order of plus or minus five degrees C. at a set point of up to 200 degrees C. Though it may be theoretically possible to achieve this level of uniformity using traditional heater construction methods, several iterations of the design may be required and the results lack manufacturing repeatability. Additionally, traditional heater construction often lead to very complex heater system design and finely controlled thermal balancing that can be affected by and thrown off by unpredictable changing environmental conditions.
Additionally, high tech industries are demanding that heated systems operate at higher and higher temperatures, often pushing the envelope for materials capability.
Thermal system designers require better methods for protecting the heaters, especially at higher operating temperature ranges, and for creating the desired high level of thermal uniformity.
SUMMARY
The above-mentioned needs are met by a method, article of manufacture, and a method of manufacturing for incorporating a thermally conductive substrate between an electrical resistance heater and a target heating surface for uniform heating.
In one embodiment, a piping system comprises a resistive heating circuit, a target heating surface, and a thermally conductive substrate adjoining (or abutting) both the heating circuit and the heating surface. The thermally conductive substrate can be composed of aluminum or some other material for heat spreading.
In another embodiment, a material for heat spreading has a thermal conductivity sufficient to evenly heat a section of the target surface within tolerance requirements of a sensitive application. The even heating can eliminate hot spots and cold spots of a temperature gradient along an axis of the piping system.
In yet another embodiment, an insulator surrounds a surface of the heating circuit.
In still another embodiment, the heating circuit increases a temperature of gas or fluid being transported through the piping system.
The features and advantages described in this summary and in the following detailed description are not all-inclusive, and particularly, many additional features and advantages will be apparent to one of ordinary skill in the relevant art in view of the drawings, specification, and claims hereof. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter, resort to the claims being necessary to determine such inventive subject matter.
BRIEF DESCRIPTION OF THE FIGURES
In the following drawings like reference numbers are used to refer to like elements. Although the following figures depict various examples of the invention, the invention is not limited to the examples depicted in the figures.
FIG. 1 is a schematic diagram showing a cross-section view of a pipe, perpendicular to an axis, having a thermally conductive substrate, according to an embodiment of the present invention.
FIG. 2 is a schematic diagram showing a cross section view of a pipe, along an axis, having a thermally conductive substrate, according to an embodiment of the present invention.
FIG. 3 is a chart illustrating a heating gradient of a conventional pipe of the prior art compared to a heating gradient of a piping system having a thermally conductive substrate, according to an embodiment of the present invention.
FIG. 4 is a flow chart illustrating a method for creating thermal uniformity in a heated media delivery system, according to an embodiment of the present invention.
DETAILED DESCRIPTION
A method, an article of manufacture, and a method of manufacturing, is disclosed, for incorporating a thermally conductive substrate between an electrical resistance heater and a target heating surface. By employing this method, electrical resistance heaters can operate more safely at higher temperatures, with more uniformity, and system thermal uniformity is greatly enhanced. The following detailed description is intended to provide example implementations to one of ordinary skill in the art, and is not intended to limit the invention to the explicit disclosure, as one of ordinary skill in the art will understand that variations can be substituted that are within the scope of the invention as described.
FIG. 1 is a schematic diagram showing a cross-section view of a pipe 100 (or weldment system), perpendicular to an axis, having a thermally conductive substrate according to an embodiment of the present invention. The pipe can be used to transport a heated media 110 (or a substrate) such as gas, fluid, or mobile solids. A heat sink substrate 120 (or thermally conductive substrate) transports heat from a resistance-style heater 130 (or resistance heating circuit) to a heated media (or target heating surface such as a media carrier composed of PFA-type plastic or stainless steel). In one embodiment, the resistance-style heater 130 is a thermocoupler.
The pipe 100 is heated to mitigate condensation within the lines, for more uniform delivery of the substance. The pipe is adapted for use in sensitive applications, such as a clean room in which delivery of gaseous doping agents in CVD, MOCVD or LPCVD processes, wafer cleaning processes, are used in the manufacture of LEDs, LCDs and other components. This application is particularly sensitive due to the microscopic size of electrical circuits generated in a clean room which have a low tolerance for variations in media temparture. Other exemplary implementations include medical applications, such as heated PFA lines and tubing for dialysis machines, and a thermal angel for a blood transfusion. One of ordinary skill in the art will recognize that many other applications are possible.
In some embodiments, the pipe 100 is a section of a piping system. A piping specialist can modify an off-the shelf the pipe. Also, a manufacturer can assemble and produce the pipe 100 as a finished product. These modified pipes can then be delivered on-site and installed for a particular application.
FIG. 2 is a schematic diagram showing a perspective view of a pipe 200 with a heater assembly, along an axis, having a thermally conductive heat sink substrate 210 according to an embodiment of the present invention. Both horizontal and vertical cross-sections are shown in the perspective view. In one embodiment, a heat sink substrate 210 does not have a uniform thickness. Therefore, the heater substrate can be built to conform to non-uniform surfaces and ensure that they are heated evenly.
In some embodiments, an outer surface of the pipe 200 is substantially even despite the non-uniformity of the inner surface. The inner surface can be uneven as a result of a joint between two members, or an elbow. Also, circumference can change in order to create an increased or reduced pressure on the media.
A thermocouple 240 is embedded in the heat sink substrate 210 . A hole can be bored during retrofitting of an off the shelf pipe, or pre-bored during manufacture. By moving the thermocouple 240 away from the resistance-style heater 220 , a better temperature reading is taken. Additionally, an epoxy can be used to backfill a boring cavity, for an even better temperature reading.
In one embodiment, the resistance-style heater 220 is permanently bonded directly to a substrate. As a result, the resistance-style heater 220 remains engaged with a heat sink in a manner that eliminates hot-spots along the heater circuit. Additionally, an expected service life of the heater circuit can be extended. A heater control (not shown) can receive a feedback signal from the thermocouple 240 and adjust the resistance-style heater 220 as needed to maintain a target temperature.
In one embodiment, insulation 230 is then used around the outside of the heater for physical protection of the resistance-style heater 220 and for plant safety and to prevent heat loss. But the insulation 230 becomes less important to creating thermal uniformity than is the case in a system without a substrate.
In another embodiment, a substrate is custom-shaped to conform to a target surface. For example, an inside diameter of the substrate to exactly conform to the outside diameter of the target piping system (see FIG. 1 ) This system is designed in a clam-shell arrangement that is clamped around the outside of the target piping or weldment system, allowing easy removal for system repair or maintenance.
FIG. 3 is a chart illustrating a comparison of heating gradients. Line 301 represents a conventional piping system while line 302 represents a piping system having a thermally conductive substrate. As can be seen, the dramatic hot and cold spots of line 301 are substantially eliminated or reduced in line 302 . Thus, the improved piping system of line 302 is far more uniform and predictable. In one embodiment, when employed in a high-tech fluid or gas delivery system, the piping system will meet the required design criteria for both temperature control and thermal uniformity. One important design criteria can be related to temperature variation along an axis of the piping system.
Improvements in thermal uniformity are dramatic and instantly recognizable. In FIG. 3 , the thermal profile across a typical heated weldment piping system employing traditional electrical resistance heat with silicone-rubber insulation is shown in line 301 . Large peaks and valleys were measured, which correspond to hot spots along the heater circuit and to cold spots in the flow path. These hot spots represent likely failure points as the electrical resistance heater can be driven beyond the material's safe operating temperature, and the cold spots represent locations where the conditions of the process fluids flowing through the piping system could fall below the desired operating band.
Another advantage to this design approach is that since the thermal profile is flattened across the entire heated system, thermal performance is more predictable and accurate thermal models can be created. This allows the system designer to create custom thermal profiles, such as a system with one end or portion colder than another.
In one embodiment, the piping system is used for applications with relatively tight tolerance levels, such as semiconductor processing. Precise and linear thermal gradients can be created using this approach, allowing a predictable rise from one target temperature to another within a system. When using conventional heating methods this sort of flexibility is only possible by employing multiple control zones, sophisticated temperature controllers, and accepting the wide uniformity swings inherent to conventional heating methods.
FIG. 4 is a flow chart illustrating a method 400 for creating thermal uniformity in a heated media delivery system, according to an embodiment of the present invention.
At step 410 , a heat sink substrate is attached to a media carrier that delivers a media such a gas, liquid, or a mobile solid.
At step 420 , a heater circuit is attached to a surface portion of the heat sink substrate in a manner that substantially uniformly heats the media carrier. In turn, the substance itself is substantially uniformly heated as well.
At step 430 , a temperature sensor is mounted. The temperature sensor can be mounted to allow a more uniform reading of the temperature. In particular, some temperature sensors are typically mounted with the heating element. The heating element has different contours of hot and cold spots depending how far away the temperature is from a wire carrying the heat.
In one implementation of the current invention, a hole is bored within heat sink substrate. By placing probes of the temperature sensor within the bored holes, away from hot and cold spots, a more accurate temperature reading is taken. The temperature reading is less affected by whether the heater circuit is currently heating or cooling, and by coil patterns of the heater circuit. In still another embodiment, the bored hole is then backfilled with an epoxy or other suitable substance to remove any air pocket that may introduce inaccuracies to the temperature reading.
Example Specifications:
In one embodiment, electrical resistance heater insulated with silicone rubber, Kapton polyimide, polyester film or any other appropriate electrical insulator. Operating temperature range is from ambient to approx. 300 degrees C.
Substrate material can be Aluminum or Aluminum alloys, Copper or copper alloys, carbon fiber, thermally conductive plastic or other thermally conductive rigid or semi-rigid material suitable to the required temperature range of the system.
Insulation can be made from silicone rubber, fiberglass, polyimide or other materials as required by physical and thermal design criteria.
Electrical power requirements can be anything required by the application. Typical voltage range is 12 VDC to 240 VAC, and typical power ranges from fractional wattage to hundreds of watts.
Measurement and control is accomplished using integrated temperature sensors, thermostats, thermal fuses and other devices as required by the application.
As will be understood by those familiar with the art, the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Likewise, the particular naming and division of the portions, modules, agents, managers, components, functions, procedures, actions, layers, features, attributes, methodologies and other aspects are not mandatory or significant, and the mechanisms that implement the invention or its features may have different names, divisions and/or formats.
Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention. | A piping system comprises a resistive heating circuit, a target heating surface, and a thermally conductive substrate adjoin (or abutting) both the heating circuit and the heating surface. The thermally conductive substrate can be composed of aluminum or some other material for heat spreading. A material for heat spreading has a thermal conductivity sufficient to evenly heat a section of the target surface within tolerance requirements of a sensitive application. The even heating can eliminate hot spots and cold spots of a temperature gradient along an axis of the piping system. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method of producing 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (referred to as “BPTMC” hereinafter). More particularly, the invention relates to a method of producing high purity BPTMC by an acid condensation reaction of phenol with 3,3,5-trimethylcyclohexanone (referred to as “TMC” hereinafter), wherein a resultant solution comprising BPTMC and phenol obtained as a reaction product is isolated and purified by a simple procedure.
[0003] 2. Description of the Related Art
[0004] In recent years, BPTMC has been used, for example, as raw materials for synthetic resins for the production of optical products such as optical disks, as well as for example as a raw material for polycarbonate resins for optical use. For these uses there is a strong need for producing colorless high purity BPTMC which is free of not only reaction byproducts but also of byproducts that are generated in the treatment for the purification of the reaction product, such as high boiling point byproducts and colored byproducts, residual phenol and trace impurities such as sodium, in a simple, highly selective, high yield procedure.
[0005] According to one known example of the method of producing BPTMC using TMC and phenol as raw materials, phenol is generally reacted with TMC in the presence of an acid catalyst, the resultant reaction mixture is neutralized after completion of the reaction, and an aqueous phase is removed, after which a phenol adduct with BPTMC is crystallized and isolated by cooling, the resulting adduct (adduct crystal) is dephenolized to obtain BPTMC. Conventionally, a steam distillation method and an evaporation method are generally used for removing phenol from this phenol adduct (dephenolization) as described in Japanese Patent Application Laid-open No. H02-088634, Published Japanese Translation of PCT Application No. H08-505644, and the like. However, a disadvantage of using these methods is that the resulting BPTMC is thermally deteriorated to cause coloration.
[0006] Also a method of producing colorless high purity BPTMC without impurities is disclosed in International Patent Publication No. WO 02/22533, in which the abovementioned phenol adduct is dissolved in a crystallizing solvent comprising an aromatic carbohydrate solvent and water, after which the crystals of BPTMC are crystallized (recrystallization), and then the resulting crystals are filtered.
SUMMARY OF THE INVENTION
[0007] As a result of studies on means to further simplify the process in the above-mentioned production method, the present inventors have found a method in which high purity BPTMC can be obtained without recrystallization and thus completed the invention.
[0008] According to the present invention, there is provided a method of producing 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (BPTMC) in which a phenol adduct with BPTMC is crystallized from a solution comprising BPTMC and phenol, the resultant phenol adduct is isolated and then phenol is removed from said phenol adduct to obtain BPTMC, the method being characterized in that said phenol adduct is washed with a washing solution comprising phenol and water and then the phenol adduct thus washed is decomposed by heating in an aqueous solvent upon the isolation of said phenol adduct.
[0009] Further, according to the present invention, there is provided a method of producing BPTMC characterized in that the temperature of the solution comprising BPTMC and phenol is gradually lowered upon the crystallization of the phenol adduct with BPTMC (BPTMC-phenol adduct) from the solution in the abovementioned production method.
[0010] According to the method of producing BPTMC of the present invention, high purity BPTMC which is colorless and excellent in hue and has a low phenol content and further an extremely low content of metal impurities such as sodium and sulfur can be obtained in high yield without carrying out such a complicated operation as redissolution and recrystallization of the phenol adduct, upon the purification of the BPTMC-phenol adduct containing impurities such as byproducts and metals.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] The present invention is a method of producing 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (BPTMC) in which a phenol adduct with BPTMC is crystallized from a solution comprising BPTMC and phenol, the resultant phenol adduct is isolated and then phenol is removed from said phenol adduct to obtain BPTMC, the method being characterized in that said phenol adduct is washed with a washing solution comprising phenol and water and then the phenol adduct thus washed is decomposed by heating in an aqueous solvent upon the isolation of said phenol adduct.
[0012] In the present invention, the solution comprising BPTMC and phenol can be any solution containing BPTMC and phenol and is not particularly limited, but preferably an oil phase containing BPTMC and phenol, which is obtained by reacting phenol and 3,3,5-trimethylcyclohexane in the presence of an acid catalyst, neutralizing the resulting reaction mixture after completion of the reaction and then removing a water phase; this water phase is cooled to crystallize the BPTMC-phenol adduct and the crystallized BPTMC-phenol adduct (phenol adduct crystal) is isolated, for example, by filtration to obtain the BPTMC-phenol adduct. In this case, the resulting phenol adduct crystal generally contains isomers, high boiling point byproducts such as polymers, colored byproducts and trace impurities such as sodium, besides BPTMC and phenol. Therefore, colorless high purity BPTMC could not generally be obtained without such operations as dissolution, recrystallization and filtration of this BPTMC-phenol adduct using a solvent.
[0013] However, the present inventors have found that high purity BPTMC can be obtained by washing this BPTMC-phenol adduct using a washing solution comprising phenol and water and then decomposing the washed phenol adduct by heating in an aqueous solvent. Presumably impurities in the abovementioned BPTMC-phenol adduct are mostly adhered onto the surface of the crystals and can be removed by washing with an aqueous phenol solution, so that the high purity BPTMC can be obtained simply by a thermal decomposing operation in an aqueous solution without such operations as redissolution and the like.
[0014] In the present invention, the phenol concentration of the aqueous phenol solution comprising phenol and water used for washing the BPTMC-phenol adduct is not particularly limited, but generally in the range of 5-90% by weight, preferably in the range of 8-80% by weight, more preferably in the range of 10-70% by weight. The amount of the aqueous phenol solution for washing is not particularly limited, but may generally be about 0.5 fold or more by weight of the BPTMC-phenol adduct. Further, the temperature of the aqueous phenol solution for washing ranges generally from room temperature to 80° C., preferably 30-70° C. The pressure for washing is not particularly limited, but is generally normal pressure.
[0015] The method of washing is not particularly limited, but the washing can be carried out, for example, by placing the BPTMC-phenol adduct and the aqueous phenol solution in a flask, stirring at about 60° C. for about 30 minutes and then filtrating for washing, or by placing the BPTMC-phenol adduct in a centrifugal dryer and spraying an aqueous phenol solution while spinning.
[0016] Next, the washed BPTMC-phenol adduct is decomposed by heating in an aqueous solvent. More specifically, the thermal decomposition in an aqueous solvent is carried out, for example, by placing the BPTMC-phenol adduct and water in a reaction vessel and heating under normal pressure or reduced pressure, thereby decomposing the adduct while distilling out generated phenol and water.
[0017] Further, according to the present invention, upon the crystallization of the BPTMC-phenol adduct from the solution comprising BPTMC and phenol in the above-mentioned production method, the high purity phenol adduct can be obtained as large crystals by gradually cooling said solution, which enables the production of colorless higher purity BPTMC by washing such BPTMC-phenol adduct using the abovementioned washing solution comprising phenol and water and then thermally decomposing the resulting washed BPTMC-phenol adduct in an aqueous solvent.
[0018] More specifically, for example, phenol and TMC are reacted in the presence of an acid catalyst, the reaction mixture obtained is neutralized after completion of the reaction, and then the water phase is removed, after which the resulting oil phase containing BPTMC and phenol is gradually cooled with a certain temperature gradient, preferably with 5-8° C./hour. In this way, crystals of BPTMC-phenol adduct having a large diameter with fewer impurities can be obtained.
[0019] The present invention will be explained by the following reference examples and examples; however, these examples are not construed to limit the scope of the invention.
REFERENCE EXAMPLE 1
[0020] Into a 1-L four necked flask equipped with a thermometer, a dropping funnel, a reflux condenser, and a stirrer were placed 188 g (2.0 moles) of phenol, 9.9 g of water, and 0.5 g of a 75% aqueous phosphoric acid solution, the temperature was adjusted to 20° C., and the air in the reaction system was replaced with nitrogen gas while stirring, after which hydrogen chloride gas was introduced. The gas component inside the reaction vessel was analyzed and the volumetric concentration of hydrogen chloride gas was adjusted to 80%.
[0021] While maintaining the temperature at 20° C., 21 g of a 15% aqueous solution of methyl mercaptan sodium salt was added dropwise, and then a mixture of 188 g (2.0 moles) of phenol and 70.0 g (0.5 mole) of 3,3,5-trimethylcyclohexanone was added dropwise over a period of 3 hours. After completion of the addition dropwise, the reaction was continued for another 3 hours while maintaining the temperature at 20° C. After completion of the reaction, the resulting reaction mixture was identified using liquid chromatography and NMR analysis, which showed that the product was the BPTMC of interest and the yield (molar quantity of BPTMC produced/molar quantity of material TMC) was 89.3% (as measured by liquid chromatography).
[0022] After completion of the reaction, the resulting reaction mixture was neutralized at pH 6.5 by adding an 18% aqueous sodium hydroxide solution while maintaining the temperature at 40-50° C. Next, the temperature of the reaction mixture thus neutralized was raised to 95° C. to dissolve the generated BPTMC adduct crystals, after which the resulting water phase was removed by separation, and the temperature of the oil phase obtained was gradually lowered to 40° C. with a temperature gradient of about 6° C./hour to crystallize the BPTMC-phenol adduct, and thus 177.9 g of crystals of the BPTMC-phenol adduct were obtained by centrifugal filtration. The result of liquid chromatography analysis showed that the adduct crystals thus obtained were consisted of 133.4 g of BPTMC, 44.2 g of phenol and 0.3 g of remaining and had an APHA color value of 90 (10% methanol solution, as measured by the JIS method). Further, the trace impurities were 170 ppm sodium (as measured by atomic adsorption spectrometry) and 300 ppm sulfur (as measured by inductively coupled plasma atomic emission spectrometry).
[0023] Further, the analytical values in the following examples and comparative examples are all measured in the same manner as described in Comparative Example 1 above.
EXAMPLE 1
[0024] Into a centrifugal dryer (Sanyo Rikagaku Kikai Seisakusho) equipped with a 10-cm diameter basket and a 200-mesh filter cloth was placed 30 g of the crystals of BPTMC-phenol adduct obtained in Reference Example 1, and then 60 g of a 10% phenol aqueous solution (a mixture of 10% by weight phenol and 90% by weight water) at 30° C. was sprinkled onto the phenol adduct crystals over a period of about 1-2 minutes at a rotating speed of 4000 rpm at normal temperature and under normal pressure.
[0025] Then the rotating speed was raised to 4000 rpm or more to separate the solid portion from the liquid.
[0026] Next, 28 g of the washed adduct and 84 g of water were placed into a four necked flask equipped with a thermometer, a stirrer, and a distillation device to distil out phenol and water by heating under normal pressure. The resultant water-phenol mixture was cooled and then filtered by centrifugation, and the resultant filtrate was dried under reduced pressure to obtain 21.4 g of the purified BPTMC product of interest.
[0027] The yield was 95% based on the phenol adduct crystals, and the product had an APHA color value of 40, a phenol content of 210 ppm (measured by liquid chromatography analysis; the phenol content was measured in the same manner in the following Examples and Comparative Examples), a BPTMC purity of 99.9% (measured by high performance liquid chromatography analysis; the purity was measured in the same manner in the following Examples and Comparative Examples), a metal impurity (sodium) level of less than 5 ppm and a sulfur content of less than 1 ppm.
EXAMPLE 2
[0028] A purified BPTMC product (20 g) was obtained in the same manner as described in Example 1, except that a 70% phenol aqueous solution was used in place of the 10% phenol aqueous solution used in Example 1. The yield was 88% based on the phenol adduct crystals, and the product had an APHA color value of 20, a phenol content of 300 ppm, a BPTMC purity of 99.9%, a metal impurity (sodium) level of less than 5 ppm and a sulfur content of less than 1 ppm.
EXAMPLE 3
[0029] A purified BPTMC product (19 g) was obtained in the same manner as described in Example 2, except that the 70% phenol aqueous solution used in Example 2 was heated to 60° C. for use in washing.
[0030] The yield was 84% based on the phenol adduct crystals, and the product had an APHA color value of 10, a phenol content of 150 ppm, a BPTMC purity of 99.9%, a metal impurity (sodium) level of less than 5 ppm and a sulfur content of less than 1 ppm.
COMPARATIVE EXAMPLE 1
[0031] The reaction was carried out as described in Reference Example 1 and the reaction mixture obtained after completion of the reaction was neutralized at pH 6.5 by adding an 18% aqueous sodium hydroxide solution while maintaining the temperature at 40-50° C. Next, the temperature of the reaction mixture thus neutralized was raised to 95° C. to dissolve the generated BPTMC adduct crystals, after which the resulting water phase was removed by separation, and the temperature of the oil phase obtained was rapidly lowered to 40° C. with a temperature gradient of about 20° C./hour to crystallize the BPTMC-phenol adduct, and the crystals of the BPTMC-phenol adduct were obtained by centrifugal filtration.
[0032] The resulting phenol adduct crystals had an APHA color value of 120.
[0033] Next, 30 g of the adduct crystals thus obtained and 90 g of water were placed into a four necked flask equipped with a thermometer, a stirrer, and a distillation device to distil out phenol and water by heating under normal pressure. Then this water mixture was cooled and then filtered by centrifugation, and the resultant filtrate was dried under reduced pressure to obtain 20.2 g of the purified BPTMC product of interest.
[0034] The product had an APHA color value of 130, a phenol content of 340 ppm, and a BPTMC purity of 99.7% and thus could not be a high purity product.
COMPARATIVE EXAMPLE 2
[0035] The adduct crystals (30 g) used in Example 1 were washed with 180 g of water heated to 90° C. The resultant crystals were dried under reduced pressure to obtain a purified BPTMC product.
[0036] The product had an APHA color value of 80, a phenol content of 1900 ppm, and a BPTMC purity of 99.5% and thus could not be a high purity product.
[0037] It will be understood by those of skill in the art that numerous and various modifications can be made without departing from the spirit of the present invention. Therefore, it should be clearly understood that the forms of the present invention are illustrative only and are not intended to limit the scope of the present invention. | A method of producing 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane comprising: crystallizing a phenol adduct of 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane from a solution comprising 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and phenol; washing the phenol adduct with a washing solution comprising phenol and water; decomposing by heating the washed phenol adduct in an aqueous solvent to remove phenol from the phenol adduct, thereby obtaining pure 1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane. | 2 |
CROSS-REFERENCE
[0001] This application claims the benefit of U.S. Provisional application No. 60/383,564, filed May 28, 2003, which is incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] Surface modification plays an important role in micro-array biomolecule detection technology for controlling backgrounds and spot morphology. Several modifications were developed using different type of commercially available silanes such as silyl amines, aldehydes, thiols etc. for immobilization of biomolecules such as oligonucleotides. After coating the surface with reactive silanes, the next challenge is immobilization of required biomolecules on the modified surface. The surface loadings always vary with different silanes and even same silane may not give reproducible results. Reproducibility of optimum surface loading has always been a great challenge in this field since surface loading dictates the performance of the assay. Even with simple linear molecules for immobilization, the optimum loading on the surface is difficult to achieve.
[0003] Attaching DNA to a modified glass surface is a central step for many applications in DNA diagnostics industry including gene expression analysis. In general, DNA can be attached to a glass surface either through non-covalent, ionic interactions, or through multi-step processes or simple coupling reactions. Several methods have been reported in the literature using glass surface modified with different types of silylating agents 1-6 . All these reported methods involve silylating step which uses expensive reagents and analytical tools. Also, these methods are also multi-step processes that are labor intensive and expensive 8-9 . Earlier reported methods have involved a laborious synthesis and time consuming procedure 7 . Indeed, many of the current immobilization methods suffer from one or more of a number of disadvantages. Some of these are, complex and expensive reaction schemes with low oligonucleotide loading yields, reactive unstable intermediates prone to side reactions and unfavorable hybridization kinetics of the immobilized oligonucleotide. The efficient immobilization of oligonucleotides or other molecules on glass surface in arrays requires a) simple reliable reactions giving reproducible loading for different batches, b) stable reaction intermediates, c) arrays with high loading and fast hybridization rates, d) high temperature stability, e) low cost, f) specific attachment at either the 5′- or 3′-end or at an internal nucleotide and g) low background.
[0004] The present invention represents a significant step in the direction of meeting or approaching several of these objectives.
SUMMARY OF THE INVENTION
[0005] The present invention fulfills the need in the art for methods for the attachment of molecules such as oligonucleotides onto unmodified surfaces such as a glass surface without the need for laborious synthetic steps, with increase surface loading densities, and with greater reproducibility and which avoids the need for pre-surface modifications. Molecules such as DNA can be silylated at either the 3′ or 5′ ends as discussed below and the 3′ or 5′-silylated DNA may then be covalently attached directly to a surface such as a pre-cleaned glass surface (Scheme) for use in hybridization assays. Furthermore, thorough the use of certain silylating reagents, it is now possible to further enhance surface loading densities by using modified silylating agents having multiple molecules attached thereto. The present invention thus provides novel methods for attaching molecules onto a substrate, devices prepared by such methods, and compositions. This method provides great advantages over the present technology in terms of simplicity, cost, speed, safety, and reproducibility.
[0006] Thus, in one embodiment of the invention, a method is provided for immobilizing a molecule onto a surface, said method comprising the steps of:
[0007] (a) contacting the molecule with an agent so as to form a reactive intermediate, said agent having a formula i:
(R 1 )(R 2 )(R 3 )Si—X—NCY i
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; and Y represents oxygen or sulfur, with the proviso that at least one of R 1 , R 2 or R 3 represents C 1 -C 6 alkoxy; and
[0008] (b) contacting the reactive intermediate with said surface so as to immobilize the molecule onto said surface.
[0009] In one aspect of this embodiment, a method is provided for immobilizing a molecule onto a glass surface.
[0010] In another embodiment of the invention, a method is provided for immobilizing a molecule onto a surface, said method comprising the steps of:
[0011] (a) contacting Si(NCY) 4 wherein Y represents oxygen or sulfur with an agent so as to form a first reactive intermediate, said agent having a formula ii:
(R 1 )(R 2 )(R 3 )Si—X-Z ii
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; and Z represents a hydroxy or amino group, with the proviso that at least one of R 1 , R 2 or R 3 represents C 1 -C 6 alkoxy;
[0012] (b) contacting the first reactive intermediate with a molecule so as to form a second reactive intermediate;
[0013] (c) contacting the second reactive intermediate with said surface so as to immobilized the molecule onto said surface. The method allows for the production of branched captured molecules structures such as branched oligonucleotides on a surface which is useful for enhancing detection of target analytes such as nucleic acids.
[0014] In one aspect of this embodiment of the invention, a method is provided for immobilizing a molecule onto a glass surface.
[0015] In another embodiment of the invention, a compound is provided having the formula iii:
(R 1 )(R 2 )(R 3 )Si—X—NHCYL-M iii
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; L represents a linking group; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represent C 1 -C 6 alkoxy.
[0016] In another embodiment of the invention, a compound is provided having a formula iv:
(R 1 )(R 2 )(R 3 )Si—X-Z-CYNH—Si (NCY) 3 iv
wherein R 1 , R 2 and R 3 independently represents C1-C6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH, with the proviso that at least one of R 1 , R 2 , or R 3 represents C 1 -C 6 alkoxy.
[0017] In another embodiment of the invention, a compound is provided having a formula v:
(R 1 )(R 2 )(R 3 )Si—X-Z-CYNH—Si (NHCYL-M) 3 v
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; L represents a linking group; and Z represents oxygen or NH; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represent C 1 -C 6 alkoxy.
[0018] In another embodiment of the invention, a compound is provided having a formula vi:
((R 1 )(R 2 )(R 3 )Si—X-Z-CYNH) 2 —Si (NCY) 2 vi
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH, with the proviso that at least one of R 1 , R 2 , or R 3 represents C 1 -C 6 alkoxy.
[0019] In another embodiment of the invention, a compound is provided having a formula vii:
((R 1 )(R 2 )(R 3 )Si—X-Z-CYNH) 2 Si (NHCYL-M) 2 vii
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; L represents a linking group; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represents C 1 -C 6 alkoxy.
[0020] In another embodiment of the invention, kits are provided for preparing modified substrates. The kits may include reagents for silyating molecules and optional substrates.
[0021] These and other embodiments of the invention will become apparent in light of the detailed description below.
DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a scheme that illustrates one embodiment of the invention. The scheme shows the modification of a molecule such as an oligonucleotide modified at either a 3′-amino or 5′-amino to produce a silylated DNA intermediate. This silylated intermediate is then spotted onto a surface of a substrate, e.g., glass substrate and washed.
[0023] FIG. 2 illustrates spot morphology after spotting a substrate with a DMF solution containing a silylated DNA in water or DMF. Branching and spreading of the spot was observed with the aqueous solution.
[0024] FIG. 3 illustrates spot morphology using a DMF solution containing a silyated DNA spotted on a overhydrated substrate. Branching of the spot was observed with the over hydrated substrate.
[0025] FIG. 4 illustrates spot morphology with an aqueous solution containing no silylated DNA (blank control) and with silylated DNA (silyl).
[0026] FIG. 5 is (a) a scheme that illustrates another embodiment of the invention. The scheme shows the coupling of a tetraisocyanatosilane with a 1-amino-4-triethoxysilylbenzene to form a first reactive intermediate 4. The reactive intermediate is then coupled to a oligonucleotide having a free 3′ or 5′-amino group to silylated DNA intermediate as a second reactive intermediate containing three molecules bound thereto. This silylated intermediate is then spotted onto a surface of a substrate, e.g., glass substrate. In part (b), a scheme is provided that illustrates another embodiment of the invention. The scheme shows the coupling of a tetraisocyanatosilane with a 1-amino-4-triethoxysilylbenzene to form a first reactive intermediate 4. The reactive intermediate is then coupled to a oligonucleotide having a free 3′ or 5′-amino group to silylated DNA intermediate as a second reactive intermediate containing two molecules bound thereto.
[0027] FIG. 6 illustrates the results of detection of M13 capture sequences using a DNA array chip prepared as described in Example 1 (method no. 1). In plate no. 1, a non-complementary nanoparticle-labeled oligonucleotide probe was used. In plates nos. 2 and 3, a specific complementary nanoparticle-labeled oligonucleotide probe was used. As expected, the plates using the specific complementary probes showed detection events. See Example 3.
[0028] FIG. 7 illustrates the results of detection of Factor V target sequence using a sandwich hybridization assay. A DNA array chip was prepared as described in Example 1 (method no. 1) using Factor V capture probe. The DNA chip performed as expected. See Example 4.
[0029] FIG. 8 illustrates the results of detection of MTHFR target sequence using a DNA array chip prepared as described in Example 1 (method no. 1). The DNA chip performed as expected. Plate No. 1 shows that the detection probe does not hybridized above its melting temperature. Plate No. 2 showed detection of a 100 mer MTHFR synthetic target. Plate No. 3 showed detection of a MTHFR PCR product. See Example 5. See Example 5.
[0030] FIG. 9 illustrates the results of detection of Factor V target sequence using a DNA array chip prepared as described in Example 1 (method no. 1). The DNA chip performed as expected. No non-specific background noise was observed. See Example 6.
[0031] FIG. 10 illustrates the results of detection of Factor V target sequence using a DNA array chip prepared as described in Example 1 (method no. 1). The DNA chip performed as expected. The probes reacted specifically to the target sequence and no cross-hybridization between the probes and targets was observed. See Example 7.
DESCRIPTION OF THE INVENTION
[0032] All patents, patent applications, and references cited herein are incorporated by reference in their entirety.
[0033] As defined herein, the term “molecule” refers to any desired specific binding member that may be immobilized onto the surface of the substrate. The “specific binding member,” as defined herein, means either member of a cognate binding pair. A “cognate binding pair, ” as defined herein, is any ligand-receptor combination that will specifically bind to one another, generally through non-covalent interactions such as ionic attractions, hydrogen bonding, Vanderwaals forces, hydrophobic interactions and the like. Exemplary cognate pairs and interactions are well known in the art and include, by way of example and not limitation: immunological interactions between an antibody or Fab fragment and its antigen, hapten or epitope; biochemical interactions between a protein (e.g. hormone or enzyme) and its receptor (for example, avidin or streptavidin and biotin), or between a carbohydrate and a lectin; chemical interactions, such as between a metal and a chelating agent; and nucleic acid base pairing between complementary nucleic acid strands; a peptide nucleic acid analog which forms a cognate binding pair with nucleic acids or other PNAs. Thus, a molecule may be a specific binding member selected from the group consisting of antigen and antibody-specific binding pairs, biotin and avidin binding pairs, carbohydrate and lectin bind pairs, complementary nucleotide sequences, complementary peptide sequences, effector and receptor molecules, enzyme cofactor and enzymes, and enzyme inhibitors and enzymes. Other specific binding members include, without limitation, DNA, RNA, polypeptide, antibody, antigen, carbohydrate, protein, peptide, amino acid, carbohydrate, hormone, steroid, vitamin, drug, virus, polysaccharides, lipids, lipopolysaccharides, glycoproteins, lipoproteins, nucleoproteins, oligonucleotides, antibodies, immunoglobulins, albumin, hemoglobin, coagulation factors, peptide and protein hormones, non-peptide hormones, interleukins, interferons, cytokines, peptides comprising a tumor-specific epitope, cells, cell-surface molecules, microorganisms, fragments, portions, components or products of microorganisms, small organic molecules, nucleic acids and oligonucleotides, metabolites of or antibodies to any of the above substances. Nucleic acids and oligonucleotides comprise genes, viral RNA and DNA, bacterial DNA, fungal DNA, mammalian DNA, cDNA, mRNA, RNA and DNA fragments, oligonucleotides, synthetic oligonucleotides, modified oligonucleotides, single-stranded and double-stranded nucleic acids, natural and synthetic nucleic acids. Preparation of antibody and oligonucleotide specific binding members is well known in the art. The molecules (M) have at least one or more nucleophilic groups, e.g., amino, carboxylate, or hydroxyl, that are capable of linking or reacting with the silylating agents to form a reactive silylated molecule which is useful for modifying the surfaces of substrates. These nucleophilic groups are either already on the molecules or are introduced by known chemical procedures.
[0034] As defined herein, the term “substrate” refers any solid support suitable for immobilizing oligonucleotides and other molecules are known in the art. These include nylon, nitrocelluose, activated agarose, diazotized cellulose, latex particles, plastic, polystyrene, glass and polymer coated surfaces. These solid supports are used in many formats such as membranes, microtiter plates, beads, probes, dipsticks, optical fibers, etc. Of particular interest as background to the present invention is the use of glass and nylon surfaces in the preparation of DNA microarrays which have been described in recent years (Ramsay, Nat. Biotechnol., 16: 40-4 (1998)). The journal Nature Genetics has published a special supplement describing the utility and limitations of microarrays (Nat. Genet., 21(1): 1-60 (1999). Typically the use of any solid support requires the presence of a nucleophilic group to react with the silylated molecules of the invention that contain a “reactive group” capable of reacting with the nucleophilic group. Suitable nucleophilic groups or moieties include hydroxyl, sulfhydryl, and amino groups or any moiety that is capable of coupling with the silyated molecules of the invention. Chemical procedures to introduce the nucleophilic or the reactive groups onto solid support are known in the art, they include procedures to activate nylon (U.S. Pat. No. 5,514,785), glass (Rodgers et al., Anal. Biochem., 23-30 (1999)), agarose (Highsmith et al., J., Biotechniques 12: 418-23 (1992) and polystyrene (Gosh et al., Nuc. Acid Res., 15: 5353-5372 (1987)). The preferred substrate is glass.
[0035] The term “analyte,” or “target analyte” as used herein, is the substance to be quantitated or detected in the test sample using devices prepared by the method of the present invention. The analyte can be any substance for which there exists a naturally occurring specific binding member (e.g., an antibody, polypeptide, DNA, RNA, cell, virus, etc.) or for which a specific binding member can be prepared, and the analyte can bind to one or more specific binding members in an assay.
[0036] In one embodiment of the invention, a method is provided for immobilizing a molecule onto a substrate surface, said method comprising the steps of contacting the molecule with an agent so as to form a reactive intermediate, said agent having a formula i:
(R 1 )(R 2 )(R 3 )Si—X—NCY i
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; and Y represents oxygen or sulfur, with the proviso that at least one of R 1 , R 2 or R 3 represents C 1 -C 6 alkoxy; and contacting the reactive intermediate with said surface so as to immobilized the molecule onto said surface.
[0037] In practice, the molecule is contacted with the agent in solution. Generally, the molecule is dissolved in a solution and agent is added drop-wise to the molecule solution. Suitable, but non-limiting, examples of solvents used in preparing the solution include DMF, DMSO, ethanol and solvent mixtures such as DMSO/ethanol. The preferred solvent is ethanol. Water is preferably excluded from the reaction solvent because water may interfere with the efficient modification of the molecule. However, if water is necessary to increase solubility of the molecule in the solution, the amount of water generally ranges from about 0.1% to about 1%, usually no greater than 1%.
[0038] The amount of molecule to agent generally ranges from about 1 to about 1.5 typically from about 1 to about 1.1, preferably from about 1 to about 1 molar equivalents. The reaction may be performed in any suitable temperature. Generally, the temperature ranges between about 0° C. and about 40° C., preferably from about 20° C. to about 25° C. The reaction is stirred for a period of time until sufficient amount of molecule and agent reacts to form a reactive intermediate. The reactive intermediate has a structure defined by formula iii.
[0039] Thereafter, the reaction solution containing the reactive intermediate is then concentrated and dissolved in desired solvent to provide a spotting solution which is then applied to the surface of a substrate. The reactive intermediate is applied as a spotting solution. Any suitable solvent may be used to prepare the spotting solution. Suitable, but non-limiting, examples of solvents used in preparing the spotting solution include DMF, DMSO, and ethanol as well as any suitable solvent mixtures such as DMF/pyridine. Any suitable concentration of the spotting solution may be prepared, generally the concentration of the spotting solution is about 1 mM. Any suitable spotting technique may be used to produce spots. Representative techniques include, without limitation, manual spotting, ink-jet technology such as the ones described in U.S. Pat. Nos. 5,233,369 and 5,486,855;, array pins or capillary tubes such as the ones described in U.S. Pat. Nos. 5,567,294 and 5,527,673; microspotting robots (e.g., available from Cartesian); chipmaker micro-spotting device (e.g., as available from TeleChem Interational). Suitable spotting equipment and protocols are commercially available such as the ArrayIt® chipmaker 3 spotting device. The spotting technique can be used to produce single spots or a plurality of spots in any suitable discrete pattern or array.
[0040] In the preferred embodiment, the agent is triethoxysilylisocyanate. The preferred molecule is a nucleic acid.
[0041] In another embodiment of the invention, a method is provided for immobilizing a molecule onto a substrate surface, said method comprising the steps of contacting Si(NCY) 4 with an agent so as to form a first reactive intermediate, said agent having a formula ii:
(R 1 )(R 2 )(R 3 )Si—X-Z ii
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; wherein Y represents oxygen or sulfur; and Z represents a hydroxy or amino group, with the proviso that at least one of R 1 , R 2 or R 3 represents C 1 -C 6 alkoxy; contacting the first reactive intermediate with a molecule so as to form a second reactive intermediate; and contacting the second reactive intermediate with said surface so as to immobilized the molecule onto said surface.
[0042] In this embodiment of the invention, the method provide for a modification of substrate surfaces with branched molecules so as to increase molecule loading on the substrate surface. These branched molecules behave like dendrimers to enhance sensitivity in assay performance. In practice, either Si(NCO) 4 or Si(NCS) 4 are reacted with a compound of formula ii to form a first reactive intermediate having the formula iv:
(R 1 )(R 2 )(R 3 )Si—X-Z-CYNH—Si (NCY) 3 iv
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH, with the proviso that at least one of R 1 , R 2 , or R 3 represents C 1 -C 6 alkoxy.
[0043] Generally, Si(NCO) 4 or Si(NCS) 4 is dissolved in a suitable dry solvent as described above. In practice, ethanol is the preferred solvent. The resulting ethanol solution is contained in a reaction flask and a solution of formula ii compound is added to the reaction flask. The formula ii solution may include any of the dried solvents described above. In practice, ethanol is the preferred solvent. The reaction temperature generally ranges from about 0° C. to about 40° C., preferably about 22° C. The reaction mixture is allowed to stir from about 1 min to about 60 min, usually about 5 min to about 10 min, until it reaches completion. The molar amount of Si(NCO) 4 or Si(NCS) 4 to formula ii compound generally ranges from about 3:1 to 1:1, preferably about 1:1.
[0044] Thereafter, the molecule is contacted with the first reactive intermediate to form a second reactive intermediate having the formula v:
(R 1 )(R 2 )(R 3 )Si—X-Z-CYNH—Si (NHCYL-M) 3 v
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; L represents a linking group; Y represents oxygen or sulfur; and Z represents oxygen or NH; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represent C 1 -C 6 alkoxy. The linking group L may be a nucleophile that is naturally present or chemically added to the molecule such as an amino, sulfhydryl group, hydroxy group, carboxylate group, or any suitable moiety. L may represent —NH, —S—, —O—, or —OOC—.
[0045] The molecule is contacted with the first reactive intermediate in solution. Generally, the molecule is dissolved in a solvent and added dropwise to the reaction flask containing the first reactive intermediate. The molecule is generally mixed in any suitable solvent as described above. The molar amount of molecule to first reactive intermediate generally ranges from about 1 to about 10 typically from about 1 to about 3, preferably from about 1 to about 4. The reaction may be performed in any suitable temperature. Generally, the temperature ranges between about 0° C. and about 40° C., preferably from about 20° C. to about 25° C. The reaction is stirred for a period of time until sufficient amount of molecule and first reactive intermediate reacts to form a second reactive intermediate. Generally, an excess amount of molecule is used to react with the first reactive intermediate. In practice, typically at least 3 equivalents of molecule to 1 equivalent of first reactive intermediate is used.
[0046] Thereafter, the second reactive intermediate is then applied to the surface of a substrate using techniques described above.
[0047] In another aspect of this invention, if the ratio of Si(NCO) 4 or Si(NCS) 4 to formula ii compound is about 1:2 equiv./equiv., a first reactive intermediate is formed having the formula vi:
((R 1 )(R 2 )(R 3 )Si—X-Z-CYNH) 2 —Si (NCY) 2 vi
[0048] wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH, with the proviso that at least one of R 1 , R 2 , or R 3 represents C 1 -C 6 alkoxy. Preferably, R 1 , R 2 and R 3 represent methoxy, X represents phenyl, Y represents oxygen, and Z represents NH.
[0049] Thereafter, the molecule is contacted with the first reactive intermediate of formula vi as described above to produce a second reactive intermediate having the formula vii:
((R 1 )(R 2 )(R 3 )Si—X-Z-CYNH) 2 Si (NHCYL-M) 2 vii
[0050] wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; L represents a linking group; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represent C 1 -C 6 alkoxy. The linking group L may be a nucleophile that is naturally present or chemically added to the molecule such as an amino, sulfhydryl group, hydroxy group, carboxylate group, or any suitable moiety. L may represent —NH, —S—, —O—, or —OOC—. Generally, an excess amount of molecule is used to react with the first reactive intermediate. In practice, typically at least 3 equivalents of molecule to 1 equivalent of first reactive intermediate is used.
[0051] Thereafter, the second reactive intermediate is then applied to the surface of a substrate using the techniques described above.
[0052] In another embodiment of the invention, a compound is provided having the formula iii:
(R 1 )(R 2 )(R 3 )Si—X-NHCYL-M iii
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; L represents a linking group; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represent C 1 -C 6 alkoxy. The linking group L may be a nucleophile that is naturally present or chemically added to the molecule such as an amino, sulfhydryl group, hydroxy group, carboxylate group, or any suitable moiety. L may represent —NH, —S—, —O—, or —OOC—. In the preferred embodiment, R 1 , R 2 , and R 3 represent alkoxy, L represents —NH—, X represents propyl, and Y represents O. The compound is useful for modifying substrate surfaces with a desired molecule.
[0053] In another embodiment of the invention, a compound is provided having a formula iv:
(R 1 )(R 2 )(R 3 )Si—X-Z-CYNH—Si (NCY) 3 iv
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH, with the proviso that at least one of R 1 , R 2 , or R 3 represents C 1 -C 6 alkoxy. In the preferred embodiment, R 1 , R 2 , and R 3 represent ethoxy or methoxy, X represents benzyl, Y represents oxygen, and Z represents NH. The compound is useful for modifying molecules so that they can be attached to substrate surfaces.
[0054] In another embodiment of the invention, a compound is provided having a formula v:
(R 1 )(R 2 )(R 3 )Si—X-Z-CYNH—Si (NHCYL-M) 3 v
wherein R 1 , R 2 and R 3 independently represents C 1 -C 6 alkoxy, C 1 -C 6 alkyl, phenyl, or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy; L represents a linking group; X represents linear or branched C 1 -C 20 alkyl or aryl substituted with one or more groups selected from the group consisting of C 1 -C 6 alkyl and C 1 -C 6 alkoxy, optionally substituted with one or more heteroatoms comprising oxygen, nitrogen, or sulfur; Y represents oxygen or sulfur; and Z represents oxygen or NH; and M represents a molecule, with the proviso that at least one of R 1 , R 2 , or R 3 represent C 1 -C 6 alkoxy. The linking group L may be a nucleophile that is naturally present or chemically added to the molecule such as an amino, sulfhydryl group, hydroxy group, carboxylate group, or any suitable moiety. L may represent —NH, —S—, —O—, or —OOC—. In the preferred embodiment, R 1 , R 2 , and R 3 represent methoxy or ethoxy, X represents 3- or 4-phenyl, Y represents oxygen, and Z represents NH. The compound is useful for modifying molecules so that they can be attached to substrate surfaces.
[0055] In another embodiment of the invention, a device is provided for the detection of target analytes in a sample. The device comprises a surface having an immobilized molecule as a specific binding member to the target analyte, wherein said surface is prepared by any of the above methods. The preferred surface is a glass surface. The surface may have one or more different specific binding members attached thereto in an array to allow for the detection of different portions of a target analyte or multiple different types of target analytes.
[0056] In another embodiment of the invention, a kit is provided. The kit may comprise one or more containers containing any of the silylating agents mentioned above with an optional substrate, and a set of instructions.
EXAMPLES
[0057] The invention is demonstrated further by the following illustrative examples. The examples are offered by way of illustration and are not intended to limit the invention in any manner. In these examples all percentages are by weight if for solids and by volume if for liquids, and all temperatures are in degrees Celsius unless otherwise noted.
Example 1
Preparation of DNA Array Chips
[0058] This Example provides a general procedure for the covalent attachment of a molecule, e.g., 3′ or 5′-silylated DNA, directly to surfaces such as pre-cleaned glass surface via single silylated molecule or dendritic silylated molecule procedure.
[0000] (a) Method No. 1
[0059] As shown in FIG. 1 , a method is shown for attaching a 3′-amino or 5′-amino DNA molecule to a pre-cleaned glass surface. 3′-Amine linked DNA is synthesized by following standard protocol for DNA synthesis on DNA synthesizer. The 3′ amine modified DNA synthesized on the solid support was attached through succinyl linker to the solid support. After synthesis, DNA attached to the solid support was released by using aqueous ammonia, resulting in the generation of a DNA strand containing a free amine at the 3′-end. The crude material was purified on HPLC, using triethyl ammonium acetate (TEAA) buffer and acetonitrile. The dimethoxytrityl (DMT) group was removed on the column itself using triflouroacetic acid.
[0060] After purification, 1 equivalents of 3′-amine linked DNA was subsequently treated with 1.2 equivalents of triethoxysilyl isocyanate (GELEST, Morrisville, Pa., USA) for 1-3 h in 10% DMSO in ethanol at room temperature. Traces of water that remained in the DNA following evaporation did not effect the reaction. After 3 h, the reaction mixture was evaporated to dryness and spotted directly on pre-cleaned glass surface using an arrayer (Affymetrix, GMS 417 arrayer with 500 micron pins for spotting). Typically, 1 mM silylated DNA was used to array a glass surface and the arrayed substrate is then kept in the chamber for 4 h-5 h. Thereafter, the slides were incubated in nanopure water for 10 minutes to remove the unbound DNA, washed with ethanol, and dried in the dessicator. After drying, these plates were tested with target DNA samples.
[0061] In a preliminary study using linear silyl oligonucleotides prepared by the above procedure to spot a glass surface, it was observed that spotting in DMSO or DMF medisurprisingly controlled spot branching or diffusion. See FIG. 2 . The spot morphology was clean and discrete. If the substrate was overhydrated in the dessicator chamber prepared by filing a portion of a chamber with water and storing the glass slides on a rack above the water level overnight, the slides become overhydrated. Undesirable branching of the spot was observed on overhydrated slides, even when DMSO or DMF solvent is used. See FIG. 3 . When water was used as the sole solvent for spotting, the resultant spots were branched out and spread to other spots. See FIG. 4 . Without being bound to any theory of operation, an aqueous spotting solution and/or the presence of water in a overhydrated substrate results in the polymerization of silyl oligonucleotides and thus interfered with the modification of the surface with the desired molecule. Thus, dried polar aprotic solvents such as DMF, DMSO and dried polar solvents like ethanol, isopropanol and mixture of solvents like DMF/Pyridine were found to be suitable solvents for arraying the silyl modified oligonucleotides. The presence of water (>1%) in the spotting solution or over hydration of slidesresults in spot branching after arraying. Spot branching is undesirable because it may lead to false positive results in binding studies.
[0000] (b) Method No. 2
[0062] As shown in FIG. 5 , a method is shown for attaching multiple 5′ or 3′ amino DNA molecules to a glass surface. To 1 equivalent of silyl amine in dry acetonitrile, 1.2 equivalents of tetraisocyante is added dropwise and the reaction mixture is stirred at room temperature for 10 minutes to form compound 3. 5′ or 3′-amine linked oligonucleotide is synthesized and deprotected using aqueous ammonia conditions by conventional procedures. After HPLC purification, 5′ or 3′-amine free oligonucleotide is treated with compound 3 in a 1:10 DMSO/ethanol (v/v) mixture. After 10 minutes, the modified oligonucleotides are evaporated under vacuum and spotted on unmodified glass surface in DMSO or DMF media.
Example 2
Detection of Factor V Target Sequence Using a DNA Array Chip
[0063] This Example illustrates that DNA plates prepared as described in Example 1 are useful for sandwich hybridization assays for detection of nucleic acid targets.
[0000] (a) Gold Colloid Preparation:
[0064] Gold colloids (13 nm diameter) were prepared by reduction of HAuCl 4 with citrate as described in Frens, Nature Phys. Sci., 241, 20 (1973) and Grabar, Anal. Chem., 67, 735 (1995). Briefly, all glassware was cleaned in aqua regia (3 parts HCl, 1 part HNO 3 ), rinsed with Nanopure H 2 O, then oven dried prior to use. HAuCl 4 and sodium citrate were purchased from Aldrich Chemical Company. Aqueous HAuCl 4 (1 mM, 500 mL) was brought to reflux while stirring. Then, 38.8 mM sodium citrate (50 mL) was added quickly. The solution color changed from pale yellow to burgundy, and refluxing was continued for 15 min. After cooling to room temperature, the red solution was filtered through a Micron Separations Inc. 1 micron filter. Au colloids were characterized by UV-Vis spectroscopy using a Hewlett Packard 8452A diode array spectrophotometer and by Transmission Electron Microscopy (TEM) using a Hitachi 8100 transmission electron microscope. Gold particles with diameters of 13 nm will produce a visible color change when aggregated with target and probe oligonucleotide sequences in the 10-35 nucleotide range.
[0000] (b) Synthesis Of Oligonucleotides:
[0065] Oligonucleotides were synthesized on a 1 micromole scale using a Milligene Expedite DNA synthesizer in single column mode using phosphoramidite chemistry. Eckstein, F. (ed.) Oligonucleotides and Analogues: A Practical Approach (IRL Press, Oxford, 1991). All solutions were purchased from Milligene (DNA synthesis grade). Average coupling efficiency varied from 98 to 99.8%, and the final dimethoxytrityl (DMT) protecting group was cleaved from the oligonucleotides to do final epiendrosterone coupling on the synthesizer itself. Capture strands were synthesized with DMT on procedure and purified on HPLC system.
[0000] (c) Purification of Oligonucleotides
[0066] Reverse phase HPLC was performed with using Agilent 1100 series system equipped with Tosch Biosep Amberchrom MD-G CG-300S column(10×118 mm, 35 μm particle size) using 0.03 M Et 3 NH + OAc − buffer (TEAA), pH 7, with a 1%/min. gradient of 95% CH 3 CN/5% TEAA. The flow rate was 1 mL/min. with UV detection at 260 nm. The final DMT attached was deprotected on HPLC column itself using 1-3% trifluoro acetic acid and TEAA buffer. After collection and evaporation of the buffer contained the DMT cleaved oligonucleotides, was then evaporated to near dryness. The amount of oligonucleotide was determined by absorbance at 260 nm, and final purity assessed by reverse phase HPLC.
[0067] The same protocol was used for epiendrosterone linked-oligonucleotides for probe preparation and no DMT removal needed 10 .
[0000] (d) Attachment Of Oligonucleotides To Gold Nanoparticles
[0068] Probes used in the Example: (3′-act tta aca ata g-a 20 -Epi-5′and 3′-t taa cac tcg c -a20-Epi-5′) (SEQ ID NO:1) was attached in the following fashion. These probes were designed for M13 target sequence detection.
[0069] A 1 mL solution of the gold colloids (15 nM) in water was mixed with excess (3.68 :M) 5′epi-endrosterone linked-oligonucleotide (33 and 31 bases in length) in water, and the mixture was allowed to stand for 12-24 hours at room temperature. Then, 100 μL of a 0.1 M sodium hydrogen phosphate buffer, pH 7.0, and 100 μL of 1.0 M NaCl were premixed and added. After 10 minutes, 10 μL of 1% aqueous NaN 3 were added, and the mixture was allowed to stand for an additional 20 hours then increased the salt concentration to 0.3. After standing 4 h at 0.3 M NaCl again increased to 1M Nacl and kept further 16 h. This “aging” step was designed to increase the surface coverage by the epi disulfide linked-oligonucleotides and to displace oligonucleotide bases from the gold surface. Somewhat cleaner, better defined red spots in subsequent assays were obtained if the solution was frozen in a dry-ice bath after the 40-hour incubation and then thawed at room temperature. Either way, the solution was next centrifuged at 14,000 rpm in an Eppendorf Centrifuge 5414 for about 15 minutes to give a very pale pink supernatant containing most of the oligonucleotide (as indicated by the absorbance at 260 nm) along with 7-10% of the colloidal gold (as indicated by the absorbance at 520 nm), and a compact, dark, gelatinous residue at the bottom of the tube. The supernatant was removed, and the residue was resuspended in about 200 μL of buffer (10 mM phosphate, 0.1 M NaCl) and recentrifuged. After removal of the supernatant solution, the residue was taken up in 1.0 mL of buffer (10 mM phosphate, 0.1 M NaCl) and 10 μL of a 1% aqueous solution of NaN 3 . Dissolution was assisted by drawing the solution into, and expelling it from, a pipette several times. The resulting red master solution was stable (i.e., remained red and did not aggregate) on standing for months at room temperature, on spotting on silica thin-layer chromatography (TLC) plates, and on addition to 2 M NaCl, 10 mM MgCl 2 , or solutions containing high concentrations of salmon sperm DNA.
[0070] For examples 2-5 we prepared different set of Factor V probes using an aqueous solution of 17 nM (150 μL) Au colloids, as described above, was mixed with 3.75 μM (46 μL) 5′-epiendrosterone-a 20 -tattcctcgcc (SEQ ID NO:2), and allowed to stand for 24 hours at room temperature in 1 ml Eppendorf capped vials. A second solution of colloids was reacted with 3.75 μM (46 μL) 5′-epiendrosterone-a 20 -attccttgcct-3′.(SEQ ID NO:3). Note that these oligonucleotides are non-complementary. The residue was dissolved using the same procedure described above and the resulting solution was stored in a glass bottle until further use.
[0000] (e) Hybridization Conditions
[0071] Stock buffer solution: For the hybridization buffer, the following stock solution was used: 3.0 NaCl, 0.3 M Na-Citrate, 10 mM MgCl 2 , 4.0 mM NaH 2 PO 4 and 0.005% SDS.
[0072] Hybridization assay was performed using diluted buffer (0.78M NaCl, 70 mM sodium citate, 2.64 mM MgCl 2 , 1.1 mM sodium phosphate, 0.01%) from the stock buffer solution by adding 0.5% of Tween. In a typical experiment procedure, target and probe were mixed with the hybridization buffer and heated the mixture at 95° C. for 5 minutes. After cooling to room temperature aliquots were transferred on to the glass substrate and placed in humidity chamber for hybridization (Different assays were done at different temperature conditions since each probe has a different melting temperature). After hybridization, plates were washed with two different wash buffers and spin dried. Plates dried were treated with silver amplification solutions (silverA+silverB) (silver amplification kit available from SIGMA, St.Louis, Mo. 63178, catalog no: S 5020 and S 5145) and the data was collected from the amplified plates using an imaging system for data collection described in (Nanosphere, Inc. assignee) U.S. patent application Ser. No. 10/210,959 and PCT/US02/24604, both filed Aug. 2, 2002, which are incorporated by reference in their entirety.
[0000] (f) Target Sequence Used
[0073] This Factor V target sequence was used in examples 2-6 for detection. M13 probes were used in example 1 for direct probe targeting to capture strand test the plates and no target detection was performed here. But from example 2-5 Factor V target detection was done in presence of Factor V probes and M13 probes. Here M13 probes served as controls. In plate no: 5 different combination of assay were performed on one plate including Factor V wild type and mismatch detection. Each well in plate no:6 was clearly defined with target and probes used.
[0074] Factor V wild type sequence:
(SEQ ID NO:4) 5′ gacatcgcctctgggctaataggactacttctaatctgtaagagcag atccctggacaggcaaggaatacaggtattttgtccttgaagtaaccttt cag 3′
[0075] Probe sequence:
Probe FV (13D): 5′-Epi-a 20 -tattcctcgcc 3′ (SEQ ID NO: 5) Probe FV (26D): 5′-Epi-a 20 -attccttgcct3′ (SEQ ID NO: 6)
[0076] Capture Strand Sequence For factor V target detection:
(SEQ ID NO:7) 5′-tcc tga tga aga tta gac att ctc gtc-NH-CO-NH- Si-(OEt) 3 -3′
[0077] Stock buffer solution: For the hybridization buffer, the following stock solution was used: 3.0 NaCl, 0.3 M Na-Citrate, 10 mM MgCl 2 , 4.0 mM NaH 2 PO 4 and 0.005% SDS.
Example 3
Detection of M13 Target Sequence Using DNA Array Chip
[0078] In this Example, probe was targeted directly to the capture strand and a detection assay was performed. Plates Nos. 1-3 were prepared as described in Example 1 (method no. 1). In Plates 2 & 3, probes ( FIG. 6 ) were clearly hybridized to the capture strand within 45 minutes. The gold colloid nanoparticles hybridized to the capture were clearly visible before silver amplification. In plate no 1 ( FIG. 6 ), a different probe was used and the assay was developed to show the specificity. After silver stain development, signals were not shown on the glass surface even after silver amplification. This experiment established the specificity of the DNA chip prepared in accordance with the invention.
[0079] M13 Capture sequence:
(SEQ ID NO: 8) 5′-tga aat tgt tat c-NH-CO-NH--Si-(OEt) 3 -3′
[0080] Probe used on plates Nos. 2-3 plates:
3′-act tta aca ata g-a 20 -Epi-5′ (SEQ ID NO: 9)
[0081] On plate no.1, a detection probe 3′-t taa cac tcg c-a 20 -Epi-5′ (SEQ ID NO:10) was used which was non-complementary to the capture strand for sequence specificity testing (no signals). This clearly showed the specificity of the both capture strand sequence and the probe. In both cases, 6 nM probe was used in diluted buffer conditions. In a typical experimental procedure, 30 μl of the diluted buffer (1.3M NaCl, 130 mM sodium citrate, 4.38 mM MgCl 2 , 1.82 mM sodium phosphate, 0.003% SDS) and 20 μl of probe (10 nM) was flooded on the arrayed glass chip and allowed to hybridize for 1.5 h at room temperature. The final concentration of probe was 4 nM and buffer concentration was 0.78M NaCl, 70 mM sodium citrate, 2.64 mM MgCl 2 , 1.1 mM sodium phosphate, 0.002% SDS. Thereafter, the chip was washed with 0.75 M sodium chloride, 75 mM citrate and 0.05% Tween buffer and then washed again with 0.5M sodium nitrate buffer. Then plates were treated with silver amplification solutions silver A+SilverB (1 mL+1 mL=total 2 mL) for 4 minutes and washed with nanopure water. Finally, the plates were exposed to the imaging system for data collection as discussed above.
Example 4
Detection of Factor V Target Sequence Using a DNA Array Chip
[0082] In this Example, two different silanized capture strands were spotted directly on the plate and detected. The plate was prepared as described in Example 1 (method no. 1). The middle row always carried the positive control capture with other capture on top and bottom rows. Here, wild type, mutant and heterozygous samples were used for the detection. All samples were showed signals in the proper place using the above mentioned assay conditions. See FIG. 7 .
[0083] a) Positive controls capture sequence:
(SEQ ID NO:10) 5′-tga aat tgt tat c-NH-CO-NH-Si-(OEt) 3 -3′
[0084] Probe used was for positive control:
3′-act tta aca ata g-a 20 -Epi-5′ (SEQ ID NO:11)
[0085] b) Probes used for target detection are:
Probe FV 13D (probe for wild type target): 5′-Epi-a 20 -tattcctcgcc 3′ (SEQ ID NO:12) Probe FV 26D (probe for mutant target): 5′-Epi-a 20 -attccttgcct3′ (SEQ ID NO:13)
[0086] Capture Strand Sequence For factor V target detection:
5′-tcc tga tga aga tta gac att ctc gtc-NH-CO-NH-- Si-(OEt) 3 -3′
[0087] Factor V wild type target sequence:
(SEQ ID NO: 13) 5′ gacatcgcctctgggctaataggactacttctaatctgtaagagcag atccctggacaggcaaggaatacaggtattttgtccttgaagtaaccttt cag 3′
[0088] Mutant Factor V target sequence:
(SEQ ID NO:14) gtaggactacttctaatctgtaagagcagatccctggacaggtaaggaat acaggtattttgtccttgaagtaaccttcag-3′
[0089] Heterozygous: 50% of wild type and 50% of mutant target.
Well 1: Heterozygous—Probe 26D was used Well 2: Heterozygous—Probe 13D was used Well 3: Control—with probe 26D, only positive control should show up Well 4: Control—with probel 3D, only positive control should show up Well 5: Mutant—target with mutant probe 26D+positive control probe Well 6: Mutant target—with wild type probe 13D+positive control Well 7: Heterozygous—with probe 26D Well 8: Heterozygous—with probe 13D Well 9: Wild type target—with mutant probe 26D Well 10: Wild type target—with wild type probe13D
Example 5
Detection of MTHFR Target Sequence on a DNA Array Plate
[0100] In this Example, an MTHFR 100 mer synthetic target and 208 base pair PCR product (10 nM˜50 nM) was used in the detection assay. The plates were prepared as described in Example 1 (method no. 1). Alternative wells were used as controls using M13 target and MTHFR 18 mer probe and did not show even traces of silver, following silver signal amplification. As shown in plate no. 1 ( FIG. 8 ), an experiment was performed at 70° C. to show that probe does not hybridize above melting temperature (MTHFR target and 18 mer probe). The results show probe specificity and that at high temperature, the probes are not binding nonspecifically to the silyl oligo-attached substrate.
[0101] 100 mer synthetic target:
(SEQ ID NO: 14) 5′-aag cac ttg aag gag aag gtg tct gcg gga gcc gat ttc atc atc acg cag ctt ttc ttt gag gct gac aca ttc ttc cgc ttt gtg aag gca tgc acc ga-3′
[0102] 18 mer probe sequence used on all three plates:
(SEQ ID NO: 15) 3′-ctg tgt aag aag gcg ttt-A 20 -Epi-5′
[0103] PCR product: 208 base pair
(SEQ ID NO: 16) 5′ ccttgaacaggtggaggccagcctctcctgactgtcatccctattgg caggttaccccaaaggccaccccgaagcagggagctttgaggctgacctg aagcacttgaaggagaaggtgtctgcgggagccgatttcatcatcacgca gcttttctttgaggctgacacattcttccgctttgtgaaggcatgcaccg acatgggcatcacttgccccatcgtccccgggatctttcccatccaggtg aggggcccaggagagcccataagctccctccaccccactctcaccgc
Experimental conditions:
[0104] In a typical experimental procedure (on plate no:2), to 30 μl of the diluted buffer (1.3M NaCl, 130 mM sodium citrate, 4.38 mM MgCl 2 , 1.82 mM sodium phosphate, 0.003% SDS), 10 μl of 18 mer probe (10 nM) and 2 μl of 100 mer synthetic target (10 μM) 8 μl of water were mixed and flooded on the arrayed glass chip and allowed to hybridize for 1.5 h at room temperature. The final concentration of probe was 2 nM and target concentration was 400 pM and buffer concentration was 0.78M NaCl, 70 mM sodium citate, 2.64 mM MgCl 2 , 1.1 mM sodium phosphate, 0.01%). After that washed with 0.75 M sodium chloride, 75 mM citrate and 0.05% Tween buffer and then washed again with 0.5M sodium nitrate buffer. After that plates were treated with silver A+SilverB (1 mL+1 mL=total 2 mL) (silver amplification kit available from SIGMA, St.Louis, Mo. 63178, catalog no: S 5020 and S 5145) for 4 minutes and washed with nanopure water. Finally plates were exposed to imaging system for data collection as discussed above. In Example 3 on plate no:2, wells no: 2 1, 4, 5, 8 are controls and controls made up with M13 synthetic target and MTHFR 18 mer probe (5′-tat gct tcc ggc tcg tat gtt gtg tgg aat tgt gag cgg ata aca att tca-3′). (SEQ ID NO: 17)
[0105] As mentioned earlier, the experiment on plate no.1 ( FIG. 8 ) was performed at 70° C. to show that above melting temperature probe 18 mer probe did not bind to the capture probe.
[0106] Plate no.3 ( FIG. 8 ) was generated following the same experimental procedure and using the same probes. 10 μl (2 nm˜10 nM) of MTHFR PCR product was used as target. Plate no.3 wells 2, 3, 6 and 7 are the controls with Factor V 99 mer mutant target and MTHFR 18 mer probe.
[0107] Factor V 99 mer Mutant Factor V target had the following sequence:
(SEQ ID NO: 18) 5′ gtaggactacttctaatctgtaagagcagatccctggacaggtaagg aatacaggtattttgtccttgaagtaacctttcag-3′)
Example 6
Detection of Factor V Target Sequence on DNA Array Plate
[0108] In this Example and in the following Example 7, the same capture strands were arrayed on the plate. The purpose of this experiment was to find out the difference in intensity of the spots after silver development when same oligomer was spotted on the slide at different places. Positive control was spotted in the middle of two Factor V 4G oligomer captures on the slide. The results are shown in FIG. 9 .
[0109] Capture strand sequence for Factor V target detection was:
5′ tcc tga tga aga tta gac att ctc gtc-NH—CO—NH—Si-(OEt) 3 -3′ (SEQ ID NO:19)
[0110] Positive capture control capture spotted was (M13):
(SEQ ID NO:20) 5′ tga aat tgt tat c-NH-CO-NH--Si-(OEt) 3 -3′
[0111] The target sequence used was wild type Factor V 99base pair single strand DNA having the following sequence:
(SEQ ID NO:21) gtaggactacttctaatctgtaagagcagatccctggacaggcaaggaat acaggtattttgtccttgaagtaacctttcag-3′)
[0112] Mutant Factor V target had the following sequence:
(SEQ ID NO:22) gtaggactacttctaatctgtaagagcagatccctggacaggtaaggaat acaggtattttgtccttgaagtaacctttcag-3′)
[0113] and probes used had the following sequence:
probe FV 13D: 5′-Epi-a 20 -tattcctcgcc 3′, (SEQ ID NO:23) probe FV 26D: 5′-Epi-a 20 -attccttgcct3′. (SEQ ID NO:24)
[0114]
Capture Strand Sequence for factor V
target detection:
5′-tcc tga tga aga tta gac att ctc
(SEQ ID NO:25)
gtc-NH-CO-NH--Si-(OEt) 3 -3′
Positive control sequence:
5′-tga aat tgt tat c-NH 2 -3′
(SEQ ID NO:26)
and
probe used for positive control
was:
3′-act tta aca ata g-a 20 -Epi-5′
(SEQ ID NO:27)
[0115] In a typical experimental procedure, to 25 μl of the diluted buffer (1.3M NaCl, 130 mM sodium citrate, 4.38 mM MgCl 2 , 1.82 mM sodium phosphate, 0.003% SDS),10 μl of probe (10 nM) and 10 μl of PCR target (15-50 nM) and 5 μl of positive control probe (10 nM) were mixed and flooded on the arrayed glass chip and allowed to hybridize for 1.5 h at room temperature. The final concentration of probe was 2 nM, and buffer concentration was 0.78M NaCl, 70 mM sodium citate, 2.64 mM MgCl 2 , 1.1 mM sodium phosphate, 0.01%). that the plates was then washed with 0.75 Sodium chloride, 75 mM citrate and 0.05% tween buffer and then washed again with 0.5M Sodium Nitrate buffer. The plates were treated with silver A+SilverB (1 mL+1 mL=total 2 mL) for 4 minutes and washed with nanopure water. Finally, the plates were exposed to the imaging system described above for data collection. Both positive control probe and target reacted probe were mixed and the assay was run to show the selectivity of the probe. The wells were identified as follows:
[0116] Wells 1, 6, 8 and 9 have only positive control probe with target and buffer.
[0117] Wells 2, 5 had both positive control probe and target probe with targets and buffer.
[0118] Wells 4, 7 and 10 have only target probe with target and buffer and here positive control probe and target were absent.
[0119] Well 3 did not have any target and positive control probe but it had target probe and buffer.
[0120] These results ( FIG. 9 ) show that probes were specific to target detection and no non-specific background noise was observed when target was absent.
Example 7
Detection of Factor V Target Sequence
[0121] In this Example, all capture strands pattern is the same as described in Example no.6. Moreover, the same experimental conditions and concentrations described in Example 6 were used to perform the assay at 52° C. Wild type and mutant targets were given in the example 6. The results are shown in FIG. 10 . The wells are identified as follows:
[0122] Well 1: Positive control probe directly probing to the capture strand in the same buffer conditions mentioned in example 4.
[0123] Well 2: Factor V Probe 5′-Epi-a 20 -attccttgcct-3′ (26D) (SEQ ID NO: 27) and Factor V 99base pair mutant target, positive control probe and buffer.
[0124] Well 3: Factor V Probe 5′-Epi-a 20 -attccttgcct-3′ (26D) (SEQ ID NO: 28) and Factor V 99base pair mutant target and hybridization buffer.
[0125] Well 4: Probe 13D and Factor V mutant PCR target, positive control and hybridization buffer.
[0126] Well 5: Probe 13D and Factor V mutant PCR target, and hybridization buffer.
[0127] Well 6: Control (MTHFR target and Probe 13D and hybridization buffer).
[0128] Well 7: Wild type Factor V target, probe (26D), positive control probe and hybridization buffer,
[0129] Well 8: Wild type Factor V target and probe (26D), and hybridization buffer.
[0130] Well 9: Wild type Factor V target, probe 13(D), positive control probe and hybridization buffer.
[0131] Well 10: Wild type Factor V target, probe 13(D), and hybridization buffer.
(SEQ ID NO:29) Probe FV 13D: 5′-Epi-a 20 -tattcctcgcc-3′ (SEQ ID NO:30) Probe FV 26D: 5′-Epi-a 20 -attccttgcct-3′
[0132] These results ( FIG. 10 ) show that probes were reacted specifically to the target and there is no cross hybridization between probes and targets were observed when probes were mixed with different targets.
REFERENCES
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1 . NucleicAcids research, vol 22, 5456-5465 (1994).
2 . NucleicAcids research, vol 24, 3040-3047 (1996).
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4 . Nucleic Acids research, vol 27, 1970-1977 (1999).
5 . Angew .Chem. Int. Ed, 38, No.9, 1297(1999)
6 . Analytical biochemistry 280, 143-150 (2000).
7. (a) Nucleic Acids research, vol. 28, No.13 E71 (2000);
(b) Huber et al. WO 01/46214, published Jun. 28, 2001 (c) Huber et al. WO 01/46213, published Jun. 28, 2001 (d) Huber et al. WO 01/46464, published Jun. 28, 2001
8 . Nucleic Acids research, vol 29, 955-959 (2001).
9 . Nucleic Acids research, vol 29, No.13 e69 (2001).
10 . Bioconjugate Chemistry, 2000, 11, 289-291 | A method for the efficient immobilization of silylated molecules such as silylated oligonucleotides or proteins onto unmodified surfaces such as a glass surface is provided. Also provided are compounds, devices, and kits for modifying surfaces such as glass surfaces. | 8 |
FIELD OF THE INVENTION
[0001] The invention relates to the field of image segmentation and more specifically to image segmentation based on deformable models.
BACKGROUND OF THE INVENTION
[0002] An implementation of image segmentation based on deformable models is described by H. Delingette in an article entitled “General object reconstruction based on simplex Meshes” in the “International Journal on Computer Vision, vol. 32, no. 2, pp. 111-146, 1999, hereinafter referred to as Ref. 1. This paper presents a method of adapting a simplex mesh to a three-dimensional (3D) object. Simplex meshes have a simple topology wherein each vertex of the simplex mesh is connected to three neighboring vertices of the simplex mesh. The adaptation of a simplex mesh is driven by external forces. Each simplex mesh vertex is attracted by an external force towards the respective image feature in the 3D image data. Image features are computed on the basis of local gradients of the image intensity field. Elastic behavior of simplex meshes, which constrains the deformation driven by external forces, is modeled by internal forces, e.g. by internal forces that minimize the local mesh curvature. The simplex mesh is iteratively adapted until the external and internal forces at each vertex cancel each other out. A refinement process for increasing the mesh resolution at highly curved parts is also described in Ref. 1. A fine-resolution mesh comprises more vertices and thus can utilize more information comprised in the image data. However, keeping the model surface smooth is computationally more demanding when a fine mesh is used.
SUMMARY OF THE INVENTION
[0003] It would be advantageous to segment an image data utilizing fine-resolution information comprised in said image data while effectively controlling smoothness of the computed model surface represented by a mesh without a substantial increase of computational cost. Computational cost comprises the processor bandwidth and the computation time. However, if one uses very fine surface sampling, i.e. fine-resolution meshes, keeping the model surface smooth may significantly increase computational cost because the model surface needs to be smoothed over large neighboring areas.
[0004] To better address this concern, in an aspect of the invention, a system for segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, comprises:
an initialization unit for initializing the coarse mesh in an image dataset space; a construction unit for constructing the fine mesh in the image dataset space based on the initialized coarse mesh;
[0007] a computation unit for computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities; and
an adaptation unit for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset.
[0009] Constructing the fine mesh in the image dataset space is based on the initialized coarse mesh and may be carried out, for example, by means of a subdivision scheme with control points comprised in the coarse mesh. The fine mesh is used by the computation unit to find features in the image dataset and to compute the external force field on the coarse mesh based on the found features. Therefore, even when the image features are sparse, the use of the fine mesh can still achieve that said features are not missed. The coarse mesh is then adapted to the image dataset by the adaptation unit using the external and the internal force fields computed by the computation unit. Since only the coarse mesh is adapted to the image dataset, keeping the modeled object surface smooth does not require a smoothing of the surface over large neighboring areas. Therefore, the computational cost of adapting the coarse mesh to an object in the image dataset is significantly lower than that of adapting the fine mesh to an object in the image dataset. The reduction in the computational cost of the adaptation far exceeds the extra computational cost added by the construction of the fine mesh by means of, for example, a subdivision scheme for subdividing the coarse mesh. Advantageously, the proposed technique can be easily integrated into existing frameworks of model-based image segmentation.
[0010] In an embodiment of the system, the fine mesh is constructed on the basis of a subdivision scheme of the coarse mesh. There are many useful subdivision schemes, e.g. the Doo-Sabin's scheme, the Catmull-Clark's scheme, and the Loop's scheme, which may be advantageously employed by the system. Most of the subdivision schemes are fast and therefore further reduce the computational cost of the segmentation task.
[0011] In an embodiment of the system, the system further comprises a determination unit for determining a resolution of the fine mesh. The determination unit is capable of determining an optimum resolution of the fine mesh. This resolution may be a function of the image data resolution and/or of the expected feature size. In a further embodiment of the system, an additional consideration is to take into account the computational cost: the finer the resolution, the higher the computational cost. Alternatively, the resolution may be determined on the basis of user input data such as a user-defined subdivision level.
[0012] In a further aspect of the invention, an image acquisition apparatus comprises a system for segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, the system comprising:
[0013] an initialization unit for initializing the coarse mesh in an image dataset space;
[0014] a construction unit for constructing the fine mesh in the image dataset space based on the initialized coarse mesh;
[0015] a computation unit for computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities; and
[0016] an adaptation unit for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset.
[0017] In a further aspect of the invention, a workstation comprises a system for segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, the system comprising:
[0018] an initialization unit for initializing the coarse mesh in an image dataset space;
[0019] a construction unit for constructing the fine mesh in the image dataset space based on the initialized coarse mesh;
[0020] a computation unit for computing an internal force field on the coarse mesh and an external force field on the coarse mesh wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities; and
[0021] an adaptation unit for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset.
[0022] In a further aspect of the invention, a method of segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, comprises:
[0023] an initialization step for initializing the coarse mesh in an image dataset space;
[0024] a construction step for constructing the fine mesh in the image dataset space based on the initialized coarse mesh;
[0025] a computation step for computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities; and
[0026] an adaptation step for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset.
[0027] In a further aspect of the invention, a computer program product to be loaded by a computer arrangement comprises instructions for segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, the computer arrangement comprising a processing unit and a memory, which computer program product, after being loaded, provides said processing unit with the capability to carry out the following tasks of:
initializing the coarse mesh in an image dataset space; constructing the fine mesh in the image dataset space based on the initialized coarse mesh;
[0030] computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities; and
[0031] adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset.
[0032] Modifications and variations thereof, of the image acquisition apparatus, of the workstation, of the method, and/or of the computer program product, which correspond to modifications of the system and variations thereof as described above can be implemented by those skilled in the art on the basis of the present description.
[0033] Those skilled in the art will appreciate that the method may be applied to three-dimensional (3D) and to two-dimensional (2D) image datasets generated by various acquisition modalities such as, but not limited to, conventional X-Ray, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Ultrasound (US), Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Nuclear Medicine (NM).
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] These and other aspects of the invention will become apparent from and will be elucidated with respect to the implementations and embodiments described hereinafter and with reference to the accompanying drawings, wherein:
[0035] FIG. 1 schematically shows a block diagram of an exemplary embodiment of the system;
[0036] FIG. 2 shows a flowchart of an exemplary implementation of the method;
[0037] FIG. 3 shows an exemplary simplex mesh;
[0038] FIG. 4 illustrates the triangular mesh dual to the simplex mesh;
[0039] FIG. 5 illustrates the first level subdivision of the dual mesh;
[0040] FIG. 6 illustrates the second level subdivision of the dual mesh;
[0041] FIG. 7 shows exemplary results of cardiac segmentation in a noisy 3D US image;
[0042] FIG. 8 schematically shows an exemplary embodiment of the image acquisition apparatus; and
[0043] FIG. 9 schematically shows an exemplary embodiment of the workstation.
[0044] The same reference numerals are used to denote similar parts throughout the Figures.
DETAILED DESCRIPTION OF EMBODIMENTS
[0045] FIG. 1 schematically shows a block diagram of an exemplary embodiment of the system 100 for segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, the system 100 comprising:
[0046] an initialization unit 110 for initializing the coarse mesh in an image dataset space;
[0047] a construction unit 120 for constructing the fine mesh in the image dataset space based on the initialized coarse mesh;
[0048] a computation unit 130 for computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities; and
[0049] an adaptation unit 140 for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset.
[0050] The exemplary embodiment of the system 100 further comprises the following optional units:
[0051] a determination unit 150 for determining a resolution of the fine mesh;
[0052] a control unit 160 for controlling the workflow in the system 100 ;
[0053] a user interface 165 for communicating with a user of the system 100 ; and
[0054] a memory unit 170 for storing data.
[0055] In the exemplary embodiment of the system 100 , there are three input connectors 181 , 182 and 183 for the incoming data. The first input connector 181 is arranged to receive data coming in from data storage such as, but not limited to, a hard disk, a magnetic tape, a flash memory, or an optical disk. The second input connector 182 is arranged to receive data coming in from a user input device such as, but not limited to, a mouse or a touch screen. The third input connector 183 is arranged to receive data coming in from a user input device such as a keyboard. The input connectors 181 , 182 and 183 are connected to an input control unit 180 .
[0056] In the exemplary embodiment of the system 100 , there are two output connectors 191 and 192 for the outgoing data. The first output connector 191 is arranged to output the data to data storage such as a hard disk, a magnetic tape, a flash memory, or an optical disk. The second output connector 192 is arranged to output the data to a display device. The output connectors 191 and 192 receive the respective data via an output control unit 190 .
[0057] Those skilled in the art will understand that there are many ways to connect input devices to the input connectors 181 , 182 and 183 and output devices to the output connectors 191 and 192 of the system 100 . These ways comprise, but are not limited to, a wired and a wireless connection, a digital network such as, but not limited to, a Local Area Network (LAN) and a Wide Area Network (WAN), the Internet, a digital telephone network, and an analog telephone network.
[0058] In the exemplary embodiment of the system 100 , the system 100 comprises a memory unit 170 . The system 100 is arranged to receive input data from external devices via any of the input connectors 181 , 182 , and 183 and to store the received input data in the memory unit 170 . Loading the input data into the memory unit 170 allows a quick access to relevant data portions by the units of the system 100 . The input data may comprise, for example, the image dataset. The memory unit 170 may be implemented by devices such as, but not limited to, a Random Access Memory (RAM) chip, a Read Only Memory (ROM) chip, and/or a hard disk drive and a hard disk. The memory unit 170 may be further arranged to store the output data. The output data may comprise, for example, the adapted coarse mesh. The memory unit 170 is also arranged to receive data from and to deliver data to the units of the system 100 , comprising the initialization unit 110 ; the construction unit 120 , the computation unit 130 , the adaptation unit 140 , the determination unit 150 , the control unit 160 , and the user interface 165 via a memory bus 175 . The memory unit 170 is further arranged to make the output data available to external devices via any of the output connectors 191 and 192 . Storing the data from the units of the system 100 in the memory unit 170 may advantageously improve the performance of the units of the system 100 as well as the rate of transfer of the output data from the units of the system 100 to external devices.
[0059] Alternatively, the system 100 may not comprise the memory unit 170 and the memory bus 175 . The input data used by the system 100 may be supplied by at least one external device, such as an external memory or a processor, connected to the units of the system 100 . Similarly, the output data produced by the system 100 may be supplied to at least one external device, such as an external memory or a processor, connected to the units of the system 100 . The units of the system 100 may be arranged to receive the data from each other via internal connections or via a data bus.
[0060] In the exemplary embodiment of the system 100 shown in FIG. 1 , the system 100 comprises a control unit 160 for controlling the workflow in the system 100 . The control unit may be arranged to check a termination condition. If the termination condition is satisfied, the system 100 may be arranged to perform final tasks and terminate the segmentation of the image dataset. Alternatively, a control function may be implemented in other units of the system 100 .
[0061] In the exemplary embodiment of the system 100 shown in FIG. 1 , the system 100 comprises a user interface 165 for communicating with the user of the system 100 . The user interface 165 may be arranged to prompt the user for and to accept a user selection of the image dataset and of the fine mesh resolution, for example. The user interface 165 may be further arranged to provide means for displaying a view rendered from the image dataset and/or for displaying the initialized and the adapted coarse mesh. Optionally, the user interface may receive a user selection of one of a plurality of modes of operation of the system 100 . In an exemplary mode, the system 100 may be arranged to use a particular coarse mesh, e.g. a simplex or a triangular coarse mesh. The modes may be implemented by the system 100 . Those skilled in the art will understand that more functions may be advantageously implemented in the user interface 165 of the system 100 .
[0062] Optionally, in a further embodiment of the system 100 , the system 100 may comprise an input device such as a mouse or a keyboard and/or a an output device such as a display Those skilled in the art will understand that a large number of input and output devices exist that can be advantageously comprised in the system 100 .
[0063] In the embodiment of the system 100 depicted in FIG. 1 , the system 100 obtains the image dataset and the coarse mesh and stores them in the memory unit 170 . The coarse mesh is initialized in the image dataset space by the initialization unit 110 . The image dataset space is determined based on the range of spatial coordinates of voxels comprised in the image dataset. The initialized coarse mesh comprises coordinates of the vertices of the coarse mesh in said image dataset space. The construction unit 120 is arranged to use the initialized coarse mesh or an adapted coarse mesh, adapted by the adaptation unit 140 , to construct a fine mesh. For example, the coarse mesh is subdivided in accordance with an appropriate subdivision scheme. The vertices of the coarse mesh are used as control points of the subdivision. Optionally, the system 100 further comprises the determination unit 150 for determining the resolution of the fine mesh, e.g. the level of the finest subdivision. The computation unit 130 uses the constructed fine mesh to compute an external force field on the coarse mesh. The external force field is determined on the basis of the scalar field of intensities comprised in the image dataset and on the basis of the constructed fine mesh. The computation unit 130 is further arranged to compute an internal force field on the coarse mesh. The internal force field depends on the geometry of the coarse mesh. The adaptation unit 140 uses the external and internal force fields to compute the deformation of the coarse mesh in terms of the new coordinates of the vertices of the coarse mesh, thus adapting the coarse mesh to the image dataset to model the object in the image dataset. The control unit 160 is arranged to control the workflow in the system 100 . The control unit 160 receives control data from the units of the system and provides the units of the system with control data. The provided control data determine the operation of the units of the system 100 . The control unit 160 may be arranged, for example, to examine whether the adapted coarse mesh satisfies an adaptation termination criterion. If the adapted coarse mesh satisfies an adaptation termination criterion, the control unit may be arranged to terminate the segmentation of the image dataset. If not, the control unit may be arranged to begin the next iteration of the adaptation cycle by requesting the construction unit 120 to construct the fine mesh on the basis of the adapted coarse mesh.
[0064] FIG. 2 shows a flowchart of an exemplary implementation of the method 200 of segmenting an image dataset based on a deformable model for modeling an object in the image dataset utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset. In an initialization step 210 , the coarse mesh is initialized in the image dataset space based on the scalar field of intensities. After the initialization step 210 , the method 100 continues to a construction step 220 for constructing the fine mesh in the image dataset space based on the initialized coarse mesh. After the construction step 220 , the method 100 continues to a computation step 230 for computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities. After the computation step 230 , the method 200 continues to an adaptation step 240 for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field. After the adaptation step 240 , the method 200 continues to an evaluation step 250 for evaluating the adaptation results. If the adaptation result is satisfactory, i.e. if the adaptation result satisfies an evaluation condition, the method 200 terminates the segmentation. Optionally, the method 200 further constructs the fine mesh based on the adapted coarse mesh in the evaluation step 260 before terminating. If the adaptation result is not satisfactory, the method 200 continues to the construction step 220 for constructing the fine mesh in the image dataset space based on the adapted coarse mesh.
[0065] The initialization unit 110 is arranged to initialize the coarse mesh in an image dataset space. The topology of the coarse mesh may be predefined, e.g. a deformable model comprising a definition of the mesh topology may be comprised in the input to the system 100 . Alternatively, the topology of the coarse mesh may be semi-automatically, i.e. with a user input, or automatically, i.e. with no user input, determined by the initialization system based on of the image dataset. Typically, the initialization comprises a manual placement of the coarse mesh and fitting of the mesh to the model object with a global transformation. First the user manually aligns the coarse model with a few, for example anatomical, landmarks identified in the image dataset and displayed in a display connected to the system 100 . Second, the positioned coarse mesh is fitted to the object in the image dataset with the use of the global transformation of the image dataset space. Typical transformations used to map the coarse mesh onto the object in the image dataset comprise rigid transformations, similarity transformations, and affine transformations. A method of fitting a simplex mesh to a 3D image dataset is described by O. Gerard et al. in Section II-B of a publication entitled “Efficient model-based quantification of left ventricular function in 3D echocardiography” in IEEE Transactions on Medical Imaging, vol. 21, no. 2, 1059-1068, 2002, hereinafter referred to as Ref. 2. Those skilled in the art will be aware that various manual, semi-automatic, and automatic initialization methods are described in the literature and that these methods may depend on the topology of the coarse mesh used. The particular choice of initialization method does not limit the scope of the claims.
[0066] The construction unit 120 is arranged to construct the fine mesh in the image dataset space on the basis of the initialized or the adapted coarse mesh. One possible way of creating the fine mesh is to use a subdivision scheme that uses vertices of the coarse mesh as control points of the subdivision scheme. Several subdivision schemes are described in the literature. For example, the Doo-Sabin's scheme described by D. Doo and M. Sabin in an article entitled “Analysis of the behavior of recursive division surfaces near extraordinary points” in Computer Aided Design, 10(6), 356-360, 1978 and/or the Catmull-Clark's scheme described by E. Catmull and J. Clark in an article entitled “Recursively generated B-spline surfaces on arbitrary topological meshes” in Computer Aided Design, 10(6), 350-355, 1978 may be used. Selecting a subdivision scheme for implementation in the construction unit 120 is a system design decision. The selection of the subdivision scheme may depend on the topology of the coarse mesh representing the surface of the modeled object in the image dataset. Optionally, a plurality of subdivision schemes may be implemented in the construction unit 120 . The subdivision scheme used may be interactively selected by a user, for example.
[0067] In an embodiment of the system 100 , the coarse mesh is a triangular mesh. Faces of triangular meshes are triangles. Each face of a triangular mesh may be subdivided using the Loop's scheme. The Loop's scheme is described by Charles Loop in his Master Thesis entitled “Smooth subdivision surfaces based on triangles.” University of Utah, Department of Mathematics, 1987. Alternatively, the coarse mesh is a quad mesh comprising quadrilateral faces and each face of the coarse mesh is subdivided using the Doo-Sabin's scheme or the Catmull-Clark's scheme.
[0068] In an embodiment of the system 100 , a fine mesh may be an arbitrary mesh. The construction unit 120 may further comprise means for mapping the fine mesh into the image dataset space on the basis of the initialized or adapted coarse mesh, for example by optimizing an internal force field defined on the fine mesh.
[0069] The computation unit 130 is arranged to compute an internal force field on the coarse mesh on the basis of the mesh geometry. A number of methods of computing an internal force field on a simplex mesh representing an object in an image dataset are described in Section 3.2 of Ref. 1. For example, the tangential internal force controls the vertex position relative to its neighbors connected by mesh edges to said vertex, and may be defined as a force proportional to the displacement of the vertex from the plane defined by its neighbors. Such an internal force minimizes curvature of the modeled surface.
[0070] The computation unit 130 is further arranged to compute an external force field on the coarse mesh using the constructed fine mesh and the scalar field of intensities. First, an external force field on the fine mesh is computed. For example, for each vertex of the fine mesh the target location of this vertex is computed. The target location of a vertex may be defined as the location of maximum variation in intensity, i.e. maximum gradient of the scalar field of intensities, on a search line. The search line may be the line crossing said vertex of the coarse mesh and substantially perpendicular to the surface defined by the neighboring vertices connected by mesh edges to said vertex. The intensity values on the search line may be derived from the scalar field of intensities comprised in the image dataset, for example using interpolation methods. The force defined by the target location may be a harmonic force proportional to the displacement of the vertex from its target location. This method is described in Section II-B of Ref. 2. More methods of computing external force fields on simplex meshes for modeling objects in image datasets are described in Section 3.2 of Ref. 1. Second, having computed the external force field on the fine mesh, the computation unit 130 is further arranged to compute the external force field on the coarse mesh. Each vertex of the coarse mesh is associated with vertices of the fine mesh. The association may be defined, for example, on the basis of the Euclidean distance of the vertex of the coarse mesh to the vertex of the fine mesh. All vertices of the fine mesh located within a sphere having a radius are defined as associated with the vertex of the coarse mesh at the center of the sphere. Said radius may be obtained from a user input device on the basis of a user input or may be determined by the computing unit 130 on the basis of the coarse mesh resolution. In a further implementation, the association may be defined on the basis of the topological distance. For example, a vertex of the fine mesh closest to the vertex of the coarse mesh is identified, and each vertex of the fine mesh for which the topological distance from this vertex to the identified vertex is less than a certain number is defined as associated with the vertex of the coarse mesh.
[0071] The external force acting on a vertex of the coarse mesh may be computed on the basis of the external forces defined on the vertices of the fine mesh associated with said vertex in one of the following ways:
[0072] the external force defined on a vertex of the coarse mesh is an average of the forces defined on the vertices of the fine mesh associated with said vertex;
[0073] the external force defined on a vertex of the coarse mesh is a weighted average of the forces defined on the vertices of the fine mesh associated with said vertex, where the weighting factors are based on a feature confidence;
[0074] the external force defined on a vertex of the coarse mesh is a force on majority vertices of the fine mesh associated with said vertex, based on a voting scheme.
[0075] The adaptation unit 140 uses the computed internal and external force fields to adapt the coarse mesh to the object in the image dataset. In one embodiment, the adaptation unit 140 is arranged to implement the method that uses the Lagrangian evolution equation described in Section 3.1 of Ref. 1 and in Section II-B of Ref. 2.
[0076] In an embodiment of the system 100 , the coarse mesh is a simplex mesh. Each vertex of the simplex mesh is connected to three neighboring vertices of the simplex mesh. A subdivision of the simplex mesh may be carried out in a few steps. First the dual mesh of the given simplex mesh is constructed. Each vertex of the dual mesh is a barycenter, i.e. a center of mass, of a polygonal face of the simplex mesh. Typically, the mass of each vertex of the simplex mesh is set to one. The dual mesh is a triangular mesh wherein the edges connect barycenters of adjacent polygonal faces of the underlying simplex mesh. Each triangular face of the dual mesh corresponds to one vertex of the simplex mesh. Second, the Loop's scheme is used to subdivide the dual mesh. Each triangular face of the dual mesh is iteratively subdivided into a plurality of triangles. In the first iteration, each triangular face is subdivided into four triangles. In the second iteration, each triangle obtained in the first iteration is further subdivided into four triangles. The subdivision may by further iterated to obtain a desired resolution of the fine mesh. The level of the subdivision, i.e. the number of iterations of the Loop's algorithm, determines the resolution of the fine mesh. FIGS. 3 to 6 illustrate the described subdivision of a simplex mesh. FIG. 3 shows an exemplary simplex mesh. FIG. 4 illustrates the triangular mesh dual to the simplex mesh shown in FIG. 3 . FIG. 5 illustrates the first level subdivision of the dual mesh shown in FIG. 4 . FIG. 6 illustrates the second level subdivision of the dual mesh shown in FIG. 4 .
[0077] The computation unit 130 is arranged to compute the external force field on the fine mesh. The vertices of the fine mesh associated with a vertex of the simplex mesh are used to compute the external force on said vertex of the simplex mesh. The external force on the vertex of the coarse mesh is the average of the forces computed on the vertices of the fine mesh associated with said vertex of the coarse mesh. Each vertex of the simplex coarse mesh is associated with one face of the triangular dual mesh defined by the barycenters of the three adjacent polygons that share said vertex of the simplex mesh. The vertices of the triangular fine mesh comprised in the subdivision of said triangular face are associated with said vertex of the simplex coarse mesh. The adaptation unit 140 uses the internal and external forces to compute the positions of the vertices of the coarse mesh using the Lagrangian evolution equation, thus adapting the coarse mesh to an object in the image dataset.
[0078] FIG. 7 shows exemplary results of a cardiac segmentation in a noisy 3D US image. The coarse mesh is shown in bold lines, while the fine mesh is shown in fine lines.
[0079] Those skilled in the art will understand that, in the absence of the damping force field, solving the Lagrangian evolution equation can be replaced by optimizing a sum of the internal and external energy terms. In an embodiment, solving the Lagrangian evolution equation is replaced with finding the minimum of said sum of the internal and external energy terms. An energy-based framework is described, for example, by J. Weese et al. in an article entitled “Shape constrained deformable models for 3D medical image segmentation” in Proc. IPMI, pp. 380-387, Springer 2001, hereinafter referred to as Ref. 3. Section 2 of Ref. 3 contains a description of the construction and of the optimization of said sum of the internal and external energy terms. Those skilled in the art will be able to modify the system 100 to be used in an energy-based framework. Thus, those skilled in the art will recognize that the choice of framework does not limit the scope of the claims.
[0080] In an embodiment of the system 100 , the system further comprises a determination unit 150 for determining a resolution of the fine mesh. The determination unit renders it possible to determine an optimum resolution of the fine mesh. This resolution may be a function of the image data resolution and/or of the expected feature size. In a further embodiment of the system, an additional consideration is to take into account the computational cost: the finer the resolution, the higher the computational cost. Alternatively, the resolution may be determined on the basis of input data such as a user-defined subdivision level.
[0081] In an embodiment of the system 100 , the control unit 160 is arranged to control the workflow of the system 100 . The control unit obtains control data from the units of the system 100 . For example, after completion of the adaptation step 240 , the control unit may be arranged to compare the adapted positions of vertices of the coarse mesh computed by the adaptation unit 140 with the positions of vertices of the coarse mesh computed by the adaptation unit 140 in the preceding iteration of the method or by the initialization unit 110 . If the obtained positions and the preceding positions are substantially equal, e.g. if the mutual difference is less than 5%, the control unit may be arranged to terminate the segmentation. The control unit may be further arranged to request the user interface 165 to prompt the user for an input and/or to request the user interface 165 to display the adapted coarse mesh, the constructed fine mesh, and/or a view rendered from the image dataset. Those skilled in the art are aware that there are many useful functions that may be advantageously implemented in the control unit 160
[0082] Although the described embodiments refer to a 3D image dataset, those skilled in the art will understand that the invention may also be applied to 2D image datasets. Those skilled in the art will be able to modify the units of the system and the steps of the method to implement the invention in the simpler case of 2D images. Those skilled in the art will also appreciate that various segmentation methods for segmenting an object in an image dataset by adapting a deformable model to said object may be advantageously exploited by the system 100 and that the segmentation method used does not limit the scope of the claims.
[0083] Those skilled in the art will understand that other embodiments of the system 100 are also possible. It is possible, among other options, to redefine the units of the system and to redistribute their functions. For example, in an embodiment of the system 100 , the functions of the control unit 160 may be assigned to other units of the system 100 . In a further embodiment of the system 100 , there may be a plurality of construction units replacing the construction unit 130 of the previous embodiments of the system 100 , where each construction unit may be arranged to apply a different subdivision scheme. The use of a subdivision scheme may be based on a user selection.
[0084] The units of the system 100 may be implemented by means of a processor. Normally, their functions are performed under the control of a software program product. During execution, the software program product is normally loaded into a memory, such as a RAM, and executed from there. The program may be loaded from a background memory, such as a ROM, hard disk, or magnetic and/or optical storage, or may be loaded via a network such as the Internet. Optionally, an application specific integrated circuit may provide the described functionality.
[0085] The order of the steps in the method 200 for segmenting an object in an image dataset is not mandatory, those skilled in the art may change the sequence of some of the steps or perform some steps concurrently, using threading models, multi-processor systems, or multiple processes without departing from the concept as intended by the present invention. Optionally, two or more steps of the method 100 of the current invention may be combined into one step. Optionally, a step of the method 100 of the current invention may be split up into a plurality of steps. Some steps of the method 100 are optional and may be omitted.
[0086] FIG. 8 schematically shows an exemplary embodiment of the image acquisition apparatus 800 that uses the system 100 , said image acquisition apparatus 800 comprising an image acquisition unit 810 connected to the system 100 via an internal connection, an input connector 801 , and an output connector 802 . This arrangement advantageously increases the capabilities of the image acquisition apparatus 800 , providing said image acquisition apparatus 800 with advantageous capabilities of the system 100 for segmenting an object in an image dataset. Examples of image acquisition apparatuses comprise, but are not limited to, a CT system, an X-ray system, an MRI system, a US system, a PET system, a SPECT system, and an NM system.
[0087] FIG. 9 schematically shows an exemplary embodiment of the workstation 900 . The workstation comprises a system bus 901 . A processor 910 , a memory 920 , a disk input/output (I/O) adapter 930 , and a user interface (UI) 940 are operatively connected to the system bus 901 . A disk storage device 931 is operatively coupled to the disk I/O adapter 930 . A keyboard 941 , a mouse 942 , and a display 943 are operatively coupled to the UI 940 . The system 100 of the invention, implemented as a computer program, is stored in the disk storage device 931 . The workstation 900 is arranged to load the program and input data into the memory 920 , and execute the program on the processor 910 . The user can input information to the workstation 900 using the keyboard 941 and/or the mouse 942 . The workstation is arranged to output information to the display device 943 and/or to the disk 931 . Those skilled in the art will understand that there are numerous other embodiments of the workstation 900 known in the art and that the present embodiment serves the purpose of illustrating the invention and should not be interpreted as limiting the invention to this particular embodiment.
[0088] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word “comprising” does not exclude the presence of elements or steps not listed in a claim or in the description. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements and by means of a programmed computer. In the system claims enumerating several units, several of these units can be embodied by one and the same item of hardware or software. The use of the words first, second, third, etc. does not indicate any particular sequence. These words are to be interpreted as names. | The invention relates to system ( 100 ) for segmenting an image dataset based on a deformable model for modeling an object in the image dataset, utilizing a coarse mesh for adapting to the image dataset and a fine mesh for extracting detailed information from the image dataset, the system comprising an initialization unit ( 110 ) for initializing the coarse mesh in an image dataset space, a construction unit ( 120 ) for constructing the fine mesh in the image dataset space based on the initialized coarse mesh, a computation unit ( 130 ) for computing an internal force field on the coarse mesh and an external force field on the coarse mesh, wherein the external force is computed based on the constructed fine mesh and the scalar field of intensities, and an adaptation unit ( 140 ) for adapting the coarse mesh to the object in the image dataset, using the computed internal force field and the computed external force field, thereby segmenting the image dataset. Since only the coarse mesh is adapted to the image dataset, keeping the modeled object surface smooth does not require a smoothing of the surface over large neighboring areas, and therefore the adaptation of the coarse mesh is much faster than the adaptation of the fine mesh. Advantageously, the proposed technique can be easily integrated into existing frameworks of model-based image segmentation. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a case to store objects, such as magnetic discs, compact discs or the like, and more particularly to such a case which is able to contain the discs in a stored condition, and conveniently display the discs in a manner for easy accessibility, when the case is in its open position.
2. Background Art
In modern computing systems, generally a plurality of magnetic discs are utilized for storage and retrieval of information which is encoded on the discs. When the discs are not in use, these must be stored in a manner to protect the discs from damage, contamination, or other debris which could impair their proper operation. In addition to storing the discs safely, it is also desirable that the discs be readily available for selection, and also for easy insertion into and removal from the storage container.
A number of disc cases or containers have appeared in recent years, and in some of these, there is a box or base container having a lid which closes the top of the container. When the lid is raised to its open position, there is a tray or other locating member which slants upwardly and forwardly from the lid which is generally at a further rearward position. Thus, the discs can be moved angularly about their bottom edge portions forwardly and rearwardly between the upwardly and rearwardly slanting lid and the forward tray. This facilitates the insertion and removal of discs, as well as the inspection of the discs for selection.
A search of the patent literature has disclosed a number of disc storage devices, and these are discussed briefly below.
U.S. Pat. No. 4,496,050--Kirchner, et al, illustrates a storage container where there is a lid pivotally mounted to a box at a pivot location spaced moderately forwardly at the rear edge of the box. There is a tray having a rear edge that is hinge mounted to the extreme rear edge of the lid. This tray has a pair of pins spaced forwardly of the hinge connection, and these pins ride in slots or cam tracks formed in the sidewall of the box. These slots have a first arcuate section and an end section which is directed forwardly. These slots cooperate with the pins in a manner to program the motion of the tray. Thus, when the lid is lifted, toward the end of the lifting motion of the lid, the tray is moved outwardly from the lid to an upwardly and forwardly extending position where the discs are displayed generally in the manner noted above.
U.S. Pat. No. 4,479,577--Eichner, et al, discloses a disc storage container where there is a first outer rectangular mounting member in which is pivotally mounted a containing member. The containing member can be stowed within the outer rectangular member, or it can be swung outwardly to an access position where the discs are accessible.
U.S. Pat. No. 4,478,335--Long, et al, shows a storage container where the lid can be swung upwardly in a manner to display the discs somewhat in the same manner as the Kirchner et al patent. The lid is pivotally mounted in the box about a pivot location spaced moderately forwardly of the rear edge of the box. There is a disc holding tray which is pivotally connected to the lid, and when the lid is raised, the tray engages the box in a manner to cause the tray to tilt forwardly to its display position.
U.S. Pat. No. 4,449,628--Egly, shows a disc storage container where the discs are essentially stored in an area adjacent the lid, with the discs being held in place by a plate member attached directly to the lid.
U.S. Pat. No. 4,387,802--Shearing et al, shows a storage container where there is a plurality of containing members which can be lifted vertically from a base container. There is no lid member pivotally connected to the base container.
U.S. Pat. No. 4,369,879--Egly, shows generally the same sort of structure as in the above-mentioned Egly patent.
U.S. Pat. No. 4,356,918--Kahle, discloses a storage container where the lid is hinge mounted to the box, and the lid is provided with a member to contain the discs. The lid can be moved to an upright position, as shown in FIG. 1 of that patent, where it is upstanding from the box, and the containing area of the box faces upwardly. The lid can also be moved further rearwardly to the position of FIG. 3 of that patent, where the box is inverted and the lid rests on the bottom surface of the box which in that position is turned upwardly.
U.S. Pat. No. 4,325,595--Solomon, shows a card file where there is a pivotally mounted lid having the pivot locations at a lower portion of the box. The lid can be swung outwardly to a down position where it holds a positioning member 20 at the proper slant for appropriate display of the files.
U.S. Pat. No. 4,225,038--Egly, shows a disc storage case where the lid can be raised, and the tray moved upwardly where it is held in position by engaging the forward upwardly positioned edge of the lid.
U.S. Pat. No. 4,091,918--Soulakis, et al, shows a containing structure having a lid which swings upwardly in a manner to lift the tray to a sloping position.
While the prior art does show a variety of containing devices which can perform the physical function of containing the discs, and in some instances displaying the discs, there is a continuing need for improvement, with regard to such factors as simplicity of design, reliability and effectiveness of operation, and also convenience and economy of manufacture and assembly. Accordingly, it is an object of the present invention to provide a storage container having a desirable balance of such features.
SUMMARY OF THE INVENTION
The case of the present invention is adapted to contain objects, such as discs, with the case having a closed position where the objects are stored within the case, and an open position where the objects are located in an easily accessible position. The case comprises a base containing member having a front end portion, a rear end portion and two side portions. The lid has a rear end portion and a front end portion. The lid is mounted to said base member for angular movement between a down closed position and an open position about a swing axis adjacent the rear end portion of the base member.
There is a carrying and display assembly that comprises a tray and a linkage means. The tray is adapted to carry the objects and is mounted within the base member in a manner to be movable between a down closed position when said lid is closed, and an up display position when said lid is in its open position.
The linkage means is operatively connected to the tray in a manner to permit limited relative angular movement between the linkage means and the tray. Also, the linkage means is operatively connected to the lid in a manner that the angular motion of the lid causes a corresponding angular motion of the linkage means. The linkage means is further characterized in that the angular motion of the linkage means resulting from movement of the lid to its open position causes the linkage means to lift a forward portion of the tray to position the tray at its display position.
The carry and display assembly as an operative connection to the base member which is responsive to the angular motion of the linkage member causing movement of the tray to its display position in a manner that a forward component of motion is imparted to a rear portion of the tray to position the tray in its display position.
Desirably, the lid is hinge mounted at a rear edge portion of said containing member, and more desirably the lid is formed integrally with said containing member. Thus, there is a hinge connection between the lid and said containing member comprising flexible material.
In the preferred form, the linkage member has a first rear pivot connection to the rear portion of the tray, and a second operative connection to the tray at a location forwardly of the first pivot connection. This second operative connection permits limited relative angular movement between the lid and the tray about the first pivot connection.
In the preferred form, the linkage member has a forward end having a slide connection with the lid, whereby when the lid is moved angularly, relative motion is permitted between the lid and the forward end of the linkage member. In the preferred form, this second operative connection comprises pin and slot means, with a generally arcuate slot being formed in one of the linkage means and the tray.
Preferably, the operative connection of the carry and display assembly comprises cam track and cam follower means operatively connected between the tray and the containing member in a manner that relative rotational movement of the tray relative to the containing member causes the forward movement component of the tray. Desirably, the cam track of the cam track and cam follower means has an upward and forward alignment, so as to cause relative forward and upward movement of a portion of the tray at a location of the cam track and the cam follower means.
In the preferred form, the tray comprises a bottom wall, two side walls, and a rear wall. The side walls of the tray are positioned adjacent side walls of the container. The cam track is mounted to the side walls of one of the tray and the containing member, and the cam follower is mounted to another of the tray and the containing member. The cam track and the cam follower are arranged so that relative rotational movement between the tray and the containing member causes an upward and forward component of movement of the tray.
Also in the preferred form, the rear wall of the tray has, relative to the bottom wall of the tray, an upward and rearward slant when the bottom wall of the tray is in a horizontal position. The tray is arranged so that in its display position, the rear wall of the tray rests against a bottom wall of the containing member so that the bottom wall of the tray has an upward and forward slope when the tray is in its display position.
In the specific configuration of the present invention, the linkage means comprises two arms mounted on opposite sides of the case.
Other features of the present invention will become apparent from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an isometric view of the case of the present invention in its closed position;
FIG. 2 is an isometric view taken from the same location as FIG. 1, but showing the case in its open position;
FIG. 3 is a sectional view taken along line 3--3 of FIG. 1, and showing the case in its closed position;
FIG. 4 is a view taken along the same line as FIG. 3, and showing the case where the lid has been moved upwardly to an intermediate position;
FIG. 5 is a view similar to FIGS. 3 and 4, but showing the lid being moved further upwardly and rearwardly relative to the position of FIG. 4, and with the tray being moved partially toward its display position;
FIG. 6 is a view similar to FIGS. 3-5, but showing the lid in its fully opened position, and the tray in its display position;
FIG. 7 is a view similar to FIGS. 3-6, but showing the lid being moved downwardly to a position where it begins to move the tray back to its storage position;
FIG. 8 is a top plan view of a tray of the present invention, shown separately from the rest of the components;
FIG. 9 is a side elevational view of the tray of FIG. 8;
FIG. 10 is a front elevational view of the tray of FIGS. 8 and 9;
FIG. 11 is a top plan view of a linkage member of the present invention, shown separately from the other components; and
FIG. 12 is a side elevational view of the linkage member of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The disc containing case 10 of the present invention comprises a box-like base container 12, a lid 14 hinge mounted to the base container 12, and a carrying and display assembly 16 which is arranged to position the contained discs in a convenient position for access when the lid 14 is in its fully opened position. This assembly 16 comprises a tray 18, and a linkage member 20 which is operatively connected between the tray 18 and the lid 14 so as to properly position the tray 18.
The base container 12 has the overall configuration of a rectangular prism and comprises a front wall 22, a rear wall 24, two side walls 26 and a bottom wall 28. The length and width dimensions of the base container 12 are approximately equal, while the height dimension is approximately 20% to 30% of the length or width dimension. Thus, when the discs (indicated in broken lines in FIG. 2 at 30) are in a generally upright displayed position, these extend well above the sidewalls 26.
The lid 14 has a main cover portion 32 extending over the top of the base container 12, and a downwardly extending peripheral lip 34 extending along the side and front edges of the cover 32. This lip 34 fits within the front wall 22 and the side walls 24. In addition, the forward side portions of the lip 34 are provided with two slideways or tracks 36 which cooperate with the linkage member 20 in a manner to be described hereinafter.
The extreme rear edge of the lid 14 is hinge mounted at 38 to the upper edge of the rear wall 24 of the base container 12. This is a "living" hinge, in that it is formed of a flexible material interconnecting the lid 14 and the rear wall 24. This hinge 38 can be formed quite conveniently by forming the base container 12 and the lid 14 as one integral plastic piece, with the thickness of the material at the hinge location 38 being made substantially thinner than the walls of the container 12 and also thinner than the structural components of the lid 14. One of the advantages of the present invention is that the components interact in such a manner so as to effectively accomplish the storage and access function of the case, while permitting the lid 14 to be mounted in this manner to the base container 12.
The tray 18 has an open trough-like configuration, and comprises a bottom wall 40, two side walls 42, and a rear wall 44. These walls 40-44 are generally planar, with the side walls 42 being perpendicular to the bottom wall 40. The rear wall 44 is slanted moderately from a perpendicular position relative to the bottom wall 40 in a manner that when the bottom wall 40 is positioned horizontally, the rear wall 44 extends upwardly and rearwardly at an angle of approximately 20°-25° from the vertical. Also, the forward edges 46 of the side walls 42 are shaped so as to be parallel to the plane of the rear wall 46. In the particular configuration shown herein, for manufacturing reasons the bottom wall 40 can be provided with a plurality of rectangular cutouts 48. (For convenience, these cutouts are shown only in FIG. 8.)
The tray 18 is provided with three pair of pin members 50-54, with each pair having the pins positioned oppositely from one another, with each being located on an outwardly facing surface of a related side wall. The pins 50 of the first pair are positioned each at an upper rear corner portion of its related sidewall 42. The pins 52 of a second pair are positioned at the same elevation as the pins 50, but are located forwardly therefrom, again with each pin 52 extending laterally outwardly from its related side wall 42. The pins 54 of the third pair are positioned directly beneath the pins 52, adjacent the lower edges of the side walls 42. The function of these pins 50-54 is to locate the tray 18 in movement between its stowed and its display position, and the manner in which this is accomplished will be described later herein.
The linkage member 20 is a unitary member and comprises two linkage arms 56, interconnected by a backplate 58. This plate 58 can be made with cutouts, such as the rectangular cutouts shown at 60. (For convenience, these cutouts 60 are shown only in FIG. 11.) The upper rear end portion of each linkage arm 56 is provided with a laterally oriented hole 62 to receive a related pin 50 from the tray 18. This pin/hole connection 50-62 forms a hinge or pivot axis about which the tray 18 rotates relative to the linkage member 20.
Each linkage arm 56 is formed with an arcuate slot 64 having its center of curvature at the location of its related hole or opening 62. The slot 64 of each arm 56 receives a related pin 52, in a manner that each pin 52 can travel the length of its related slot 64. The pin hole connection 50-62 and the pin slot connection 52-64 provide an operative connection between the linkage member 20 and the tray 18 so as to permit limited angular movement therebetween with the center of rotation being at the location of the holes 62, and the limit of relative angular rotation being determined by the length and location of the arcuate slots 64. In the preferred embodiment, the limit of this relative rotation is between about 40°-45°.
The extreme forward end of each linkage arm 56 is provided with a laterally and outwardly extending pin 66, each of which tracks or rides in a related one of the slideways 36 formed along the forward edge portions of the lid 14. The rear edge of the plate 58 is formed with a short downturned lip 68.
The inner surface of each side wall 26 of the base container 12 is formed with a cam slot 70 which receives a related one of the aforementioned pins 54. These cam slots 70 are each formed as a slideway enclosed by a periperal lip 72. These lips 72 are positioned so that the linkage arms 56 can pass freely by the lips 72. Further, the pins 54 extend outwardly a short distance further than the pins 52 so that these pins 54 can properly engage the cam slots 70.
In the particular configuration shown herein, each cam slot 70 is formed in a curve which has a greater vertical component at a lower rear location and then curves upwardly and then forwardly to end in a more horizontal direction with only a moderate upward slant. These cam slots 70 are programmed to accomplish the proper movement of the tray 18 in a manner to be discribed hereinafter.
To describe the operation of the present invention, reference will now be made to FIGS. 3-6 which show the components of the case 12 in various positions from the fully closed position of FIG. 3 to the fully opened position of FIG. 6.
In the fully closed position of FIG. 3, the bottom wall 40 of the tray 18 rests on the bottom wall 28 of the base container 12. The linkage member 20 is positioned just below the lid 14, and rests on the top edges of the side arms 42 of the tray 18. The two pins 52 are positioned at uppermost locations in their respective arcuate slots 64. The two pins 54 are positioned in the lowermost rear locations of their related cam slots 70. In the position of FIG. 3, the case 10 completely encloses the contained discs 30.
To open the case 10, the front edge of the lid 14 is grasped and swung upwardly in an arcuate path about the hinge axis 38. Because of the connection of the forward pins 66 in the slideways 36, there is a corresponding upward angular movement of the linkage member 20, with the center of rotation during this portion of movement being about the pin/hole connection 50-62. When the lid 14 reaches the position of FIG. 4 (which it occurs at approximately 40° rotation of the lid 14), the two pins 52 are positioned at the lowermost edge of the related locating slots 64.
Further rotation of the lid 14 causes a further corresponding rotation of the linkage member 20. Since the pins 52 are in the position of FIG. 4 at the uppermost location of the related slot 64, the further upward and rearward angular movement of the linkage member 26 causes a corresponding upward angular movement of the tray 18. This causes the tray 18 to begin to pivot about its lower rear edge 74 (which is formed by the juncture of the bottom wall 40 and the rear wall 44) so that the two pins 54 are caused to move upwardly. Since the pins 54 are positioned in the cam tracks 70, the pins 54 travel in an initial upward and forward path dictated by the tracks 70. This adds a component of forward motion to the lower rear edge portion 74 of the tray 18.
As the lid 14 is rotated further, it eventually reaches the full open position of FIG. 6, where it extends upwardly with a moderate forward slant. It will be noted that during movement of the lid 14 from the position of FIG. 4, through the position of FIG. 5 to the position of FIG. 6, the linkage member 20 and the tray 18 have no relative movement between one another, but rather move essentially as a single unitary member. During this phase of movement, the positioning of the tray 18 is controlled by the pins 54 moving in the cam slots 70, the engagement of the rear lower edge 74 with the bottom container wall 28, and the movement of the linkage arm pins 66 within the slideways or slots 36 formed in the lid 14.
When the lid 14 is moved to the fully opened position of FIG. 6, the tray 18 is positioned so that its rear wall 44 is horizontal and lies against the bottom wall 28 of the base container 12. The two pins 54 are positioned at the forwardmost location of the two slots 70. Because of the slope of the rear wall 44, the bottom wall 40 in the position of FIG. 6 extends essentially upwardly with a moderate forward slant. Further, the plate 58 of the linkage member 20 extends upwardly with a moderate rearward slant.
It can readily be seen by an examination of FIG. 2 that in the fully opened position the discs 30 are conveniently positioned for easy access. The lower edges of the discs 30 are positioned between the lower portions of the wa11 40 of the tray 18 and the plate 58 of the linkage member 20. Since the wall 40 and the plate 58 extend upwardly and divergently from one another, the upper portions of the discs 30 have relative freedom in being moved from a forward position to a more rearward position, as illustrated in FIG. 2. Thus, the discs 30 can easily be examined, and they can easily be inserted into, or removed from, the case 10 at selected locations.
To close the lid 14, the lid 14 is moved forwardly and then downwardly about the hinge axis 38. The movements of the components of the case 10 are generally in reverse to those described previously relative to the opening of the lid 14 to the fully opened position of FIG. 6. In FIG. 7, the lid 14 is shown moved downwardly in a manner that the two pins 52 have moved to the extreme lower edge portions of the two slots 64. Further downward movement of the lid 14 causes the tray 18 to rotate downwardly, with the pins 54 traveling rearwardly in the cam slots 70 in a manner to add a rearward component of motion to the movement of the tray 18. When the lid 14 finally reaches its fully closed position of FIG. 3, all of the components are returned to the positions indicated in FIG. 3.
An examination of the main components of the present invention will make it readily apparent that these lend themselves to effective and relatively economical manufacturing processes. For example, the lid 14 and base container 12 can be formed from plastic as a unitary member. Further, the tray 18 and the linkage member 20 each lend themselves to manufacture as integral components made from plastic.
With regard to the formation of the base container 12, another advantage of the present invention is that it is quite convenient to manufacture the box 12 by providing a second living hinge 74 at the juncture of the rear wall 24 and the bottom wall 28. Further, the rear wall 24 is formed with one or more catch elements 76 which engage an upstanding member 78 mounted to the bottom wall 28. Engagement of the catch element 76 with the member 78 hold the rear wall 24 in place.
It is to be understood that various modifications could be made to the present invention without departing from the spirit and scope of the present invention. | A case adapted to contain magnetic discs or the like, said case having a box-like containing member with a lid being hinge mounted to, and formed integrally with, the containing member. There is a tray to hold the discs in a displayed position where the tray slants upwardly and forwardly with the lid being fully opened. There is a linkage member comprising two linkage arms interconnecting the tray with the lid so as to cause upward motion of the tray. The tray further has a cam track and cam follower connection with the side walls of the case to program the motion of the tray to its proper display position. | 6 |
This application claims the priority of provisional application, Ser. No. 60/261,851 filed Jan. 15, 2001. The invention relates to archery bows and more particularly to compound archery bows utilizing separable limb and riser components.
BACKGROUND OF THE INVENTION
One of the problems with achieving accuracy has been the recoil vibration occurring as the arrow is released from the bow, which has resulted also in undue noise which startles the game. Another factor affecting accuracy is the alignment of the bow string which in the past has not provided the balance desired. To the best of my knowledge, the arrow released by prior art compound bows has not been vertically centered with the result that the torque and flex stresses on the bow upper and lower limbs has not been balanced, and accuracy has been sacrificed as a result. Moreover, the bow string has not been centered in the sense of vertical upper and lower pulley alignment and in the sense of vertical bisection of the handle.
Typical archery bows of the type presently utilized are disclosed in U.S. Pat. No. 5,975,067 issued Nov. 21, 1999, U.S. Pat. No. 6,035,841 issued Mar. 14, 2000, U.S. Pat. No. 6,082,346 issued Jul. 4, 2000, and U.S. Pat. No. 5,749,351 issued May 12, 1998 wherein the compound bow utilizes eccentric pulleys on the outer ends of the limbs to facilitate the draw and the arrow release. The present invention is directed to bows of this general character.
SUMMARY OF THE INVENTION
The present invention, in one aspect thereof, is concerned with the manner of mounting the resilient limbs to the handle riser as well as to the vertically centered alignment of the pulleys mounting the bow string along with the handle, and the positioning of the bow rest to achieve a vertically centered arrow relationship. This permits the archer to utilize a better balanced bow which is more accurate. Because of the balanced relationship achieved, the archer is presented with less torqueing stresses in the bow and less vibration is transferred via the bow limbs upon limb recoil and arrow release. Moreover, the positioning of the arrow in vertically centered position provides equal torque and flex forces on the limbs to generate more stored energy as the bow string is drawn. Another aspect of the invention is the provision of eccentric pulley assemblies which aid in achieving these desired characteristics.
A further object of the invention is to provide a limb mounting system which results in material vibration reduction and accordingly much less noise generation in the release of the arrow. This is accomplished by securing the limb inner ends to the handle riser ends by means of a novel vibration damping assembly. A limb bolt extends into a threaded vibration damping member carried by the riser at each end and a limb cup, constructed of anti-vibration material, is snugly utilized between the seat and the sides and inner end, as well as the bottom, of each limb. The installed cushioning limb cup restricts the limb from shifting laterally, and forwardly or inwardly, while permitting the limbs to flex or unflex when the archer adjusts the attachment bolt to his desired draw requirements and thereby controls the energy which will be stored in the deflected resilient limbs when the bow string is drawn.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a side elevational view of a relaxed compound single-cam archery bow utilizing the present inventive concepts;
FIG. 2 is a rear elevational view of a dual cam bow with the tensioning cable system omitted, illustrating various components of the bow shown in FIG. 1;
FIG. 3 is an enlarged fragmentary rear elevational view illustrating the relationship of the handle and bow string in more detail;
FIG. 4 is an enlarged perspective view of the handle illustrating the handle recess which mounts on the riser in a manner to provide the top to bottom centering of the bow string;
FIG. 5 is a somewhat enlarged side elevational view of the limb and riser assembly only;
FIG. 6 is an exploded view thereof on a slightly enlarged scale showing the various component parts thereof;
FIG. 7 is a similar exploded view on a more enlarged scale showing the parts at the inner end of the lower limb;
FIG. 7A is a perspective plan view showing the limb end received in the limb cup and limb seat;
FIG. 8 is a perspective elevational view of the limb pocket component on an enlarged scale;
FIG. 9 is an enlarged perspective view of the limb cup which fits in the limb pocket;
FIG. 9A is an exploded perspective plan view illustrating an alternative limb cup structure;
FIG. 10 is an enlarged perspective view of one of the identical limbs;
FIG. 10A is a perspective plan view of an alternative limb;
FIG. 11 is an enlarged perspective, exploded view of the limb bolt bushing assembly; and
FIG. 11A is a similar view disclosing an alternative embodiment;
FIG. 12 is a rear elevational view of a bow employing eccentric cam assemblies at each of its upper and lower ends;
FIG. 13 is an enlarged view of the upper end of the bow shown in FIG. 12;
FIG. 14 is an enlarged view of the lower end of the bow shown in FIG. 12;
FIG. 15 is a considerably enlarged view of eccentric pulley assembly which may be used at both ends of the bow;
FIG. 16 is an enlarged perspective view of the eccentric pulley assembly only; and
FIG. 17 is an edge elevational view of a base cam/power cam eccentric pulley assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the accompanying drawings, and in the first instance to FIG. 1 thereof, the bow assembly comprises generally upper and lower resilient limbs generally designated 10 and 11 joined in the manner to be disclosed to a rigid riser, generally designated 12 , which can be fashioned of aluminum or other suitable material. Revolvable mechanical advantage creating pulley members 13 and 14 are mounted laterally centrally at the outer ends of the limbs 10 and 11 . The members 13 and 14 may comprise regular idler pulleys or eccentric pulleys and in FIG. 1 a regular pulley is shown at 13 and an eccentric pulley at 14 . They operate in the usual manner to mount the bow string 15 shown in FIG. 1, which in the embodiment shown is part of the conventional tension cable system generally designated TC which extends between the opposite ends of the bow in the usual manner. The cables TC-1 and TC-2 of the conventional cable system, pass through spaced apart openings in a cable guard rod r which holds the cables laterally apart and displaced sufficiently from arrow 16 to avoid feather damage. Here the cable TC-1, which provides the bow string portion 15 , passes around pulley 13 and pulley 14 and secures at both ends to eccentric pulley 14 . Cable TC-2 is shown as connected to limb 10 at one end and to the pulley 14 at the other. In FIG. 2, a conventional eccentric pulley is used in the upper end of the bow at 13 a and on the lower end of the bow at 14 . It will be noted that the arrow 16 is vertically centered with respect to the axes of axles 18 and 19 on which the pulleys 13 or 13 a and 14 are mounted for rotation. This tends to prevent the bow from tilting vertically on the draw.
As FIG. 3 further indicates, the pulleys 13 or 13 a and 14 are so aligned vertically, and the handle 12 a is so mounted on the riser 12 , that the string 15 vertically bisects the bow handle 12 a in a front to rear direction. While the bow string 15 is offset with respect to the mid-portion of the riser, it is substantially centered with respect to the handle 12 a, as FIG. 3 particularly indicates. This is possible because the vertical mounting recess 12 b (FIG. 7 ), in the handle 12 a is centrally offset in the handle to define narrow riser embracing leg 12 g and wider embracing leg 17 h. Handle leg 12 h fits within the recess 12 c provided in the one side face of the riser 12 . Cap screw openings x in the handle and riser, for accommodating a fastener such as a screw, align. Plainly this centering of the bow string 15 with respect to the handle 12 a, and consequent centering of the string and arrow 16 with respect to the handle 12 a, can be accomplished alternatively by offsetting the mounting portion of the riser sufficiently that the bow string 15 bisects a handle 12 a mounted non-eccentrically on the riser 12 . The riser 12 , as usual, has a number of weight reduction openings and an arrow rest surface 12 d which is equidistant from the axes of each pulley 13 or 13 a and 14 and aligns substantially with the vertical center of the bow string 15 .
Another important aspect of the present invention is the anti-vibration mounting of the limbs 10 and 11 to the riser as disclosed particularly in FIGS. 6-11. It will be observed that each of the composite material limbs 10 and 11 , which are identical, include outer end bifurcation slots 20 within which the inner portions of the pulleys may be rotatably received, and bores 21 for receiving and securing the pulley axle pins 18 and 19 . While a mediate slot 22 is provided in each of the limbs in FIG. 10 to increase flexing capability it will be noted that the slot 22 does not extend the full length of the limbs 10 or 11 and, rather, torsion restricting portions 23 are provided at each end of the slot 22 , as shown. The inner ends of the limbs 10 and 11 are similarly bifurcated as at 24 (FIG. 7) for a purpose to be presently described. An alternative limb 10 or 11 , using like numerals to designate the respective parts, is shown in FIG. 10 A.
Bolted to the ends of the riser 12 , as with bolts 25 , are metallic (preferably aluminum) limb seats or pockets generally designated 26 (FIG. 8) having spaced openings 27 in their recessed bottom walls 26 a to accommodate the bolts 25 securing the seats 26 to the riser 12 ends. As indicated, the bottom surfaces of seat walls 26 a have recesses 26 b (FIG. 7) to receive the protrusion or key portions 12 f provided on the risers 12 to fit snugly therein. It will be noted that the limb seats or pockets 26 are of an elongate nature and have side walls (see FIG. 6) 28 joined by a generally curvilinear inner end wall 29 . The opposite end of each limb seat 26 is open as shown. An elongate opening 30 is also provided in the bottom wall 26 a of the limb seat to pass a limb attaching metallic (preferably steel) fastener assembly or bolt 31 (FIG. 7) in a manner to be presently described.
Provided to seat snugly within the limb seat 26 is a preferably molded, vibration damping limb receptor cup generally designated 32 (FIG. 9) which has similar side walls 33 joined by a similar generally curvilinear end wall 34 . Each limb cup 32 includes a bottom wall 32 a with an elongate opening 35 therein aligning with seat opening 30 to also pass the attachment bolt 31 . At its opposite end, the limb cup 32 is open to pass the inner end of the limb and mounts a pair of limb locator bosses 36 , as shown, which are received within the spaced apart blind openings 37 (FIG. 10) provided in the bottom surfaces of limbs 10 and 11 . The same bosses are provided, but not shown, in FIG. 10 A. The walls 33 and 34 of each limb cup are snugly received within and braced by the walls 28 and 29 of the limb seat component 26 with a perimetral clearance of only about 0.005 of an inch. Provided on the limb cups 32 near their outer ends are curvilinear rockers 38 which are received in the curvilinear receiving recesses 39 provided in the seats 26 . In addition to permitting some adjustment pivoting when the bolt 31 is adjusted to tension the limbs 10 and 11 to adjust the weight of the bow, they also serve as locator mechanism. It is to be understood that the limb cups 32 are formed of a polyurethane or other suitable resilient synthetic plastic material having a durometer which typically may be 60. The particular durometers mentioned in this application are not to be considered as in any way limiting and other durometers will prove useful so long as they provide the anti-vibration characteristics. A durometer range for the cups 32 is believed to be 30-90. The limbs 10 and 11 are preferably constructed in the usual manner of a composite material such as fiberglass or graphite with embedded fibers which may typically be glass or carbon to provide the requisite strength. The cups 32 need not be completely formed of the same material. In FIG. 9A an improved alternative is disclosed wherein the bosses 36 and rocker 38 are unitarily molded of a harder material such as “delrin plastic”. The term Delrin is a trademark owned by E. I. du Pont de Nemours and Co. Inc. for its acetal homopolymer plastics which are mechanically strong while also having resilience. In this version, the upper wall of the rocker is flat as at 38 a to lie in the same plane as the outer limb receiving surface of the bottom wall when the bosses 36 are inserted up through the opening 38 b and the rocker 38 is secured in opening 38 b adhesively, or in any other suitable manner. Another alternative is to cut away part of the cup bottom wall 32 a as at 32 c to receive an insert plate 32 d of material having a lower durometer than wall 32 a. This lower durometer is in the range 10-30 and preferably about 20.
As shown in FIG. 7, the bolt 31 is part of a fastener assembly which includes an aluminum washer 40 and the polyurethane anti-vibration washer 42 , typically having a durometer rating in the 50-60 area. The bolt 31 extends through the slotted opening 24 in the inner end of limb 10 or 11 , through slotted opening 35 in the limb cup 32 and 30 in the limb seat 26 and through a slot 12 s in riser 12 into a polyurethane or similar bushing generally designated 43 having a bolt receiving bore 44 provided therein. Bushings 43 seat snugly within bores 12 e provided in each end of the riser 12 inboard of each seat 26 . Provided embedded within the bushing 43 is a preferably stainless steel cylinder 45 (FIG. 11) having a threaded bolt receiving bore 46 aligning with bore 44 . End caps 47 and 48 of greater external diameter than the bushing opening 12 e (FIG. 7) are received on the reduced ends 43 a of the bushing 43 . The end caps 47 and 48 are preferably adhesively secured to the bushing ends 43 a and bear against the marginal surface of the riser surrounding the opening 12 e in which the bushing 43 is received. The durometer of the molded sleeve member 43 with reduced ends 48 may typically be in the area of 70-90. The end cap 47 - 48 durometer is preferably in the range 30-50. The purpose of the polyurethane sleeve bushing 43 is to dampen recoil vibration transmitted by the attachment bolt 31 and to resist forces tending to twist the handle 12 a. The bushing 43 and cylinder 45 also resist outward pull of the bolt 31 . The provision of the cups 32 , which cushion or absorb the recoil of the limbs 10 and 11 , prevents much of the recoil vibration from reaching the limb seats 26 and, in addition to preventing torsional forces from reaching the riser and handle, also damps vibration resulting from the flexing of the bow limbs 10 and 11 .
In FIG. 11A an improved alternative embodiment is disclosed in which bushing 43 is eliminated and cylinder 45 is formed of “Delrin” plastic as a damping body. The ends of cylinder 45 are closed as at 50 except for openings 51 . The openings 51 receive projections 52 extending from cap 47 and cap 48 which may have a durometer rating in the 15-25 range. The noise reducing caps 47 and 48 are preferably adhesively secured to cylinder 45 .
Referring now more particularly to FIGS. 12-16 a three cable draw and tensioning system is disclosed wherein novel eccentric cam pulleys are utilized at both ends of the bow. It is to be understood that one of the eccentric pulleys could be replaced by an idler pulley in another modification of the system depicted in these figures. The base cam/power cam device disclosed in U.S. Pat. No. 5,975,067, which I incorporate herein by reference, could be employed as the eccentric pulleys, with the distinction that the base cam and the power cam, which in the patent are continuous, are separated by a shouldered portion which disposes the track in the power cam at a spaced axial distance from the track in the base cam so that the tracks are no longer side by side. The importance of this distinction and the function it achieves will be discussed subsequently. Alternatively, cams of the general nature of those disclosed in U.S. Pat. No. 5,975,067 which include the shouldered portions but not all of the features claimed may be employed.
Turning now more particularly to FIGS. 12-14, where like numerals to designate previous components have been employed, the three cable system used, as illustrated in the drawings, consists of the draw string or draw cable 15 , the power cable 54 which has a yoke connection 55 to the ends of the lower axle pin 19 as shown particularly in FIG. 14, and let out/take up cable 56 which has a yoke connection 57 to both ends of the axle pin 18 at the upper end of the bow.
The base cam/power cam assembly generally designated 58 is used at the lower end of the bow and a like base cam/power cam assembly is used at the upper end of the bow. In both instances, the base cam/power cam assembly includes the partially elliptical base cam 59 having a pulley track 59 a for reception of the draw cable 15 and a power cam 60 having a pulley track 60 a for reception of one of the cables 54 or 56 . The upper eccentric mounts the cable 54 , the terminal lower end of the cable 54 a attaching to a post 61 projecting laterally from the base cam 59 , as shown particularly in FIG. 15 . The upper base cam/power cam assembly mounts the terminal end of the cable 15 on its post 62 projecting laterally from base cam 59 . The lower end base cam/power cam assembly 59 mounts the cable 56 on its attachment projection 61 and the cable 56 has a yoke connection to both ends of the upper axle pin 18 .
In FIGS. 15-17, the power cam 60 is shown as including an end 60 y abutting a post 60 b on base cam 59 and an end 60 c which embraces a tubular post 60 d on base cam 59 which is journaled on the pulley pin 18 . As previously, the base cam 59 and power cam 60 rotate in unison on the pin 18 . The upper terminal end 15 a of draw cable 15 has a yoke connection 15 a to a post 62 fixed on the opposite face of the base cam 59 and the lower terminal end has a similar connection to the base cam 59 of the lower eccentric assembly 58 . Both the base cam 59 and the power cam 60 are fixed to one another to move eccentrically about the pivot post 18 at the upper end of the bow, or 19 at the lower end of the bow. Where previously the base cam 59 and the power cam 60 have been side by side or adjacent to one another, they now are separated by a shoulder or axial projection 63 fixed on the base cam pulley 59 . This projection 63 which extends clockwisely from y to z substantially around power cam 60 in FIG. 16 reduces twisting forces and assures that the base cam/power cam assemblies will lie in vertical alignment. The projection 63 is not necessarily clockwisely continuous and may be sectionalized. Generally speaking, the axial projection of the shoulders 63 will be in the neighborhood of 0.5 to 1.25 inches around a substantive portion of the extent of the power cam 60 . In the lower part of the range, one of the shoulders 63 on the upper and lower eccentric pulleys will normally be at least sufficiently different in projection extent to best maintain cable separation. In the right hand bow depicted the projection 63 at the lower end of the bow will be the longer projection. In a left hander's bow, this will be reversed. When a sufficiently long shoulder projection in the neighborhood of 0.75 to 1.25 inches is provided, the cable guard rod r shown in FIG. 1 can be eliminated because the projections 63 on the eccentric pulley assemblies 58 hold the cables 56 and 54 sufficiently apart so that they do not touch one another or imperil the arrow feathers when the arrow is released. In the embodiment where an idler pulley is used in place of the upper eccentric, a hub part, of selected axial projection inwardly, may be used to locate the idler pulley track in vertical alignment with the lower eccentric base cam track.
The Operation
When the draw weight of the bow is adjusted via bolts 31 , the limbs 10 and 11 are free to flex or unflex with respect to bolts 31 slightly because of the slots 24 , 30 , 35 , and 12 s. The inner ends of limbs 10 and 11 are restricted resiliently by walls 34 from all but very limited, flexural movement inwardly. In operation, as the bow string 15 is pulled rearwardly to its position of maximum weight at mid-draw against the resistance of cable system TC, the limbs 10 and 11 will flex or curve in the usual manner and the cups or liners 33 will cushion the return from deflection when the arrow is released and the limbs 10 and 11 recoil. With the cups 32 constructed of a semi-rigid resilient anti-vibration material, the transfer of stresses to the limb seats or pockets and riser is dampened because the upstanding walls of the cups 32 are snugly received by the upstanding walls of the metallic limb seats and limb recoil vibration and noise is isolated. Any tendency of the limb cups 32 to rotate and impose torsional forces is also reduced and dampened because the walls 33 are snugly in engagement with the walls 28 , and walls 29 are snugly in engagement with the walls 34 . The limbs 10 and 11 are not of a thickness to project above the cup walls 33 and 34 . The provision of the washers 42 and the bushings 43 or the synthetic plastic vibration damping cylinder 45 with anti-vibration end caps 47 - 48 further damps the vibration which occurs at the moment of arrow release. The fact that the bow string 15 is in vertically centered relationship results in less torsional force being imposed on the limbs 10 and 11 and the centering of the arrow top to bottom provides greater accuracy in the shot.
Method of Construction
In constructing the bow, a normal first step is to secure the bow seats 26 to the opposite ends of the riser 12 by means of bolts 25 , with the riser surfaces 12 f fitting within the bottom recesses 26 b in cups 26 and the openings 12 s and 30 in alignment. Next the limb cups 32 are snugly fitted within the limb seats 26 , and the limbs 10 and 11 are inserted with the slots 24 in alignment with the limb cup openings 35 which are aligned with the pocket openings 30 . The anti-vibration members 43 are next inserted in the openings 12 e with the openings 44 and 46 aligned with openings 12 s, and caps 47 and 48 are then adhesively secured in position on opposite sides of the riser 12 . With the metallic washer 40 and the anti-vibration washer 42 in place on the bolts 31 , each bolt 31 is extended through the slotted openings 24 , 35 , 30 and 12 s into the bushing opening 34 and threaded into threaded opening 46 . Then, the handle 12 a, cable guard rod r, pulleys and axles, and the string and tension cable system TC may be installed in the usual manner.
The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims. | An eccentric pulley assembly is provided for a compound bow, including an eccentric base cam having a peripheral track for letting out a draw string as the bow is drawn. A power cam secured to the base cam has a cable track for taking up a power cable as the bow is drawn and a shoulder is provided for spacing the track of the base cam from the track of the power cam. | 8 |
The present invention is directed to transport of glassware on a linear conveyor from a glassware manufacturing machine to an annealing lehr or other post-manufacturing stage, and more particularly to monitoring speed of the linear conveyor.
BACKGROUND AND OBJECTS OF THE INVENTION
The science of glass container manufacture is currently served by the so-called individual section machine. Such a machine has a plurality of separate or individual manufacturing sections, each of which has a multiplicity of operating mechanisms for converting one or more charges or gobs of molten glass into hollow glass containers and transferring the containers through successive stations of the machine section. Each machine section includes one or more blank molds in which a glass gob is initially formed in a pressing or blowing operation, an invert arm for transferring the blanks to blow molds in which the containers are blown to final form, tongs for removing the formed containers onto a deadplate, and a sweepout mechanism for transferring molded containers from the deadplate onto a conveyor. U.S. Pat. No. 4,362,544 includes a background discussion of both blow-and-blow and press-and-blow glassware forming processes, and discloses an electropneumatic individual section machine adapted for use in either process.
As shown in U.S. Pat. No. 4,193,784, the individual machine sections operate in synchronism but out of phase with each other to form the glass containers and place the containers in sequence onto a linear machine conveyor. Containers on the linear machine conveyor are transferred to a linear cross conveyor, from which the containers are loaded into an annealing lehr. The sweepout stations of the individual machine sections are timed to transfer the finished containers to the machine conveyor such that the containers are in spaced groups, within which the containers are at uniform spacing from each other. Each group is transferred simultaneously to the annealing lehr. It is important to maintain a constant speed at the linear conveyors so that the containers will be at uniform spacing within each group, and the groups will be at uniform spacing with respect to each other, when they arrive at the lehr loader mechanism. U.S. Pat. No. 6,076,654 discloses a glass container handling system in which the linear machine conveyor and the linear cross conveyor are driven by associated electric motors coupled to a motor controller. A speed sensor is associated with each conveyor for providing an electrical signal to the controller indicative of conveyor speed. The control electronics controls operation of the motors to maintain the desired constant speed at each conveyor.
It is an object of the present invention to provide a glass machine system having sensors for sensing linear speed of the machine and/or cross conveyor, in which the sensor is constructed and arranged to accommodate wear at the conveyor while providing an accurate and reliable measure of conveyor speed.
SUMMARY OF THE INVENTION
A glass machine system in accordance with presently preferred embodiments of the invention includes a glassware manufacturing machine for manufacturing articles of glassware and transferring the articles to a linear conveyor, at-least one linear conveyor for receiving and transporting such articles from the machine, and a speed sensor for monitoring linear speed of the conveyor. The speed sensor includes a magnetic energy source, a magnetic energy sensor, and bracketry mounting the source and sensor adjacent to the conveyor. The conveyor affects magnetic energy coupling between the source and sensor as the conveyor passes adjacent to the sensor. Electronic circuitry is responsive to signals from the sensor for determining linear speed of the conveyor. The conveyor preferably takes the form of a chain conveyor having teeth along an undersurface for engaging a motor-driven pulley to drive the conveyor. The teeth are magnetically permeable, and passage of the teeth affects magnetic coupling between the energy source and energy sensor of the speed sensor. The control electronics preferably is coupled to the pulley drive motor for maintaining constant linear speed at the conveyor.
The conveyor speed sensor in the preferred embodiments of the invention includes a floating subassembly having at least one a roller for engaging an upper surface of the conveyor. The magnetic energy source and sensor are carried by the floating subassembly and disposed beneath the conveyor. In this way, constant spacing is maintained between the conveyor undersurface and the magnetic source/sensor arrangement against changes in vertical position of the conveyor due to wear of a plate over which the conveyor slides. The floating subassembly is slidable on rods carried in fixed position adjacent to the conveyor, and coil springs bias the roller(s) on the subassembly into engagement with the upper surface of the conveyor. The magnetic energy sensor in the preferred embodiments of the invention comprises a Hall sensor, although other conventional types of magnetic energy sensors may readily be employed. The magnetic energy source in the preferred embodiments of the invention comprises a permanent magnet or an electromagnet coupled to the electronic circuitry. A magnetic energy concentrator preferably is associated with the source and the sensor for concentrating passage of magnetic energy through the sensor to enhance responsiveness of the sensor to passage of conveyor drive teeth.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with additional objects, features and advantages thereof, will be best understood from the following description, the appended claims and the accompanying drawings in which:
FIG. 1 is a schematic diagram of a glass manufacturing system in accordance with a presently preferred implementation of the invention;
FIG. 2 is a side elevational view of a conveyor speed sensor in the system of FIG. 1;
FIG. 3 is a partially sectioned end elevational view of the conveyor speed sensor illustrated in FIG. 2;
FIG. 4 is a top plan view of the sensor illustrated in FIGS. 2 and 3;
FIG. 5 is a partially sectioned elevational view of a portion of the speed sensor illustrated in FIGS. 2-4;
FIG. 6 is an electrical schematic diagram of the speed sensors and conveyor motor control electronics in the system of FIG. 1;
FIG. 7 is a partially sectioned elevational view similar to that of FIG. 5 but illustrating a modified speed sensor in accordance with the present invention;
FIG. 8 is an enlarged view of a portion of FIG. 7;
FIG. 9 is a bottom plan view of the portion of the sensor illustrated in FIG. 8; and
FIG. 10 is an electrical schematic diagram of a glass machine system embodying the speed sensor illustrated in FIGS. 7 - 8 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The disclosures of above-noted U.S. Pat. Nos. 4,193,784 and 6,076,654 are incorporated herein by reference for purposes of background.
FIG. 1 illustrates a glassware manufacturing system 20 as comprising an individual section machine 22 having a plurality of sections 22 a- 22 h . Sections 22 a- 22 h are generally identical to each other, and are operated in synchronism but out of phase with each other to convert gobs of molten glass into articles 24 of glassware, such as glass containers. Each machine section includes a sweepout station 26 at which the completed articles of glassware are transferred to a linear machine conveyor 28 . The glassware is transported by conveyor 28 to a transfer device 30 , at which the containers are transferred to a linear cross conveyor 32 . Cross conveyor 32 transports the containers to a position adjacent to a lehr loader 34 , which transfers the containers in groups onto the conveyor 36 of an annealing lehr 38 . The sequence of operation of sweepout stations 24 is coordinated with conveyor speed, etc. so that the glassware articles 24 are transported in groups by conveyors 28 , 32 . The containers are preferably at uniform spacing within each group, and the groups are at a desired spacing with respect to each other. This spacing is such that the containers of each group may be loaded simultaneously by lehr loader 34 onto lehr conveyor 36 , and the lehr loader bar has sufficient time to retract before the next group of containers is in position at the loader. Machine conveyor 28 is driven by an electric motor 40 and a drive pulley 42 . Likewise, cross conveyor 32 is driven by an electric motor 44 and a drive pulley 46 . A conveyor speed sensor 48 is positioned adjacent to conveyor 28 for sensing linear speed of the conveyor, and a conveyor speed sensor 50 is positioned adjacent to conveyor 32 for sensing speed of operation of that conveyor. Speed sensors 48 , 50 provide respective inputs to an electronic controller 52 , which is connected to motors 40 , 44 for controlling speed of operation of the motors so as to obtain a desired substantially constant linear velocity at the respective conveyors.
FIGS. 2-5 illustrate the construction of speed sensor 48 associated with machine conveyor 28 . It will be understood, however, that speed sensor 50 associated with cross conveyor 32 is preferably identical to speed sensor 48 . Referring to FIGS. 2-4, machine conveyor 28 preferably comprises a chain-type conveyor having a plurality of pivotally interconnected links 54 . Links 54 are of magnetically permeable construction, such as steel. It will be understood, however, the invention may be employed in conjunction with other types of conveyors with magnetically permeable teeth, such as drive belts having strengthening metal inserts. Each link 54 has a pair of teeth that laterally align in assembly with the teeth of laterally adjacent links. These teeth engage the teeth of drive pulley 42 coupled to motor 40 (FIG. 1) to drive the conveyor. The conveyor is an endless conveyor, being trained around an idler pulley 56 (FIG. 1) at the opposing end of the conveyor. The upper reach of the conveyor slides along a wear plate 58 for supporting the weight of the conveyor and the articles of glassware carried by the conveyor. Friction between the undersurface of chain links 54 and the upper surface of plate 58 can cause wear of the plate, altering the vertical position of the conveyor. Wear of the chain link teeth and/or the pulley teeth also changes the effective radius of drive pulley 42 , which in turn changes the linear speed of the conveyor given a constant input from motor 40 . Speed sensor 48 in accordance with the present invention accommodates change in vertical position of conveyor 28 due to wear at plate 58 and/or the undersurface of conveyor 28 , and provides a measure of conveyor linear speed to control electronics 58 so that the electronics can control operation of motor 40 to maintain a constant linear velocity at the conveyor.
Speed sensor 48 includes a first fixed subassembly 57 and a second subassembly 59 that floats on subassembly 57 . Fixed subassembly 57 has a base 60 for mounting on a fixed support 62 adjacent to an edge of conveyor 28 . A pair of slides 64 , 66 are secured to base 60 by screws 68 (FIG. 2) and extend upwardly adjacent to the edge of conveyor 28 . Slides 64 , 66 are parallel to each other, and are longitudinally spaced with respect to each other in the direction of movement of conveyor 28 , as best seen in FIG. 3. A first bracket subassembly 70 includes a plate 72 having a pair of spaced linear bearings 74 , 76 that slidably embrace slides 64 , 66 respectively. An arm 78 is cantilevered to extend outwardly from plate 72 over the edge of conveyor 28 . A roller 80 is freely rotatably mounted on the end of arm 78 remote from plate 72 and extends downwardly from the lower edge of arm 78 , as best seen in FIG. 2. A pair of coil springs 82 , 84 are captured in compression between bearings 74 , 76 and caps 86 , 88 secured to the upper ends of slides 64 , 66 respectively. Thus, springs 82 , 84 urge bracket subassembly 70 downwardly with respect to slides 64 , 66 and base 60 to bring the periphery of roller 80 into rolling engagement with the upper surface of conveyor 28 .
A second bracket subassembly 90 includes an L-shaped arm 94 affixed to and suspended from plate 72 of first bracket subassembly 70 . An electromagnetic assembly 92 is mounted on the end of arm 94 so as to be positioned beneath the upper reach of conveyor 28 . Electromagnetic assembly 92 includes a permanent magnet 96 disposed between an axially aligned pair of ferromagnetic flux concentrator plugs 98 , 100 . At least one Hall effect sensor 102 , and preferably a pair of Hall effect sensors 102 , 103 are disposed adjacent to the tapering upper end of plug 98 beneath conveyor 28 . As best seen in FIG. 4, Hall sensors are at fixed spacing with respect to each other in the direction of motion of linear conveyor 28 . Magnet 96 , concentrator plugs 98 , 100 and Hall effect sensors 102 , 103 are mounted within a protective housing of insulator blocks 104 , 106 , 108 . Electrical wires 110 extend from sensors 102 , 103 through a conduit 112 on arm 94 , and thence to an electrical connector 114 for connection to motor controller 118 (FIG. 6 ). Thus, the entire bracket assembly 59 that includes subassemblies 70 , 90 “floats” with respect to base 60 at conveyor 28 for following vertical movement of the conveyor, due to wear at plate 58 or otherwise, while maintaining constant spacing between electromagnetic assembly 92 (and Hall sensors 102 , 103 ) beneath the teeth of conveyor links 54 .
As illustrated in FIG. 6, Hall sensors 102 , 103 of speed sensor 48 associated with machine conveyor 28 are connected within controller 52 through a signal conditioning circuit 116 to a motor controller 118 . Likewise, sensors 102 , 103 of speed sensor 50 associated with cross conveyor 32 are connected through a signal conditioning circuit 120 to motor controller 118 . Passage of the chain conveyor teeth above sensors 102 , 103 causes an increase in the intensity of magnetic energy conveyed through the sensors, so that the Hall sensors provide periodic outputs to the associated signal conditioning electronics and motor controller 118 at frequencies determined by the velocity of passage of the chain link teeth above the sensors. Within signal conditioning circuits 116 , 120 , the sinusoidal signals from the sensors are fed through analog peak detectors to produce square wave signals that indicate when the edge of a tooth passes the respective sensors. Since the distance between the sensors is fixed and known, the velocity of the conveyor can be readily determined. Motor controller 118 is responsive to such signals for determining linear velocity at each conveyor, and controlling the speed of operation of the associated motor 40 or 44 to maintain a desired substantially constant velocity at each conveyor. Motors 40 , 44 may be of any suitable type, as described in above-referenced U.S. Pat. No. 6,076,654. An air passage 122 (FIG. 2) extends through arm 78 of speed sensor 48 (and speed sensor 50 ). Air passage 122 terminates in a fitting 123 (FIG. 4) disposed between bearings 74 , 76 . A valve 124 is responsive to controller 118 for periodically directing air through the links of conveyor 28 (and 32 ) to blow off any magnetic particles that may have accumulated on the upper surface of insulator block due to magnetic attraction to magnet 96 .
FIGS. 7-10 illustrate a modified speed sensor and motor control electronics in accordance with the present invention. Reference numerals identical to those in FIGS. 1-6 indicate identical components, and related components are indicated by identical reference numerals followed by the suffix “a.” FIGS. 7-8 illustrate a modified second bracket subassembly 90 a as including a lower electromagnetic assembly 130 carried by arm 94 , and an upper electromagnetic assembly 132 carried by a cantilevered L-shaped arm 134 . Upper assembly 132 includes an electrical coil 136 and a ferromagnetic pole piece 138 that together form an electromagnetic for directing magnetic energy through conveyor 28 to assembly 130 . Coil 136 has a pair of leads 140 that extend through a conduit 142 to an electrical connector 114 a . Assembly 130 (FIGS. 7-9) includes a second coil 146 and a pole piece 148 that form a second electromagnet. Pole piece 148 tapers toward its lower end and is disposed adjacent to a pair of Hall sensors 102 , 103 carried by a circuitboard 150 . Coil 146 is connected by leads 152 to circuitboard 150 . Conductors 154 extend from circuitboard 150 through conduit 112 to connector 114 a for connection to controller 52 a (FIG. 10 ). Subassembly 90 a is mounted on a spring-biased upper bracket assembly of the type illustrated in FIGS. 2-4 for following vertical movement of the conveyor due to plate and conveyor wear, etc. while maintaining constant spacing between the upper and lower surfaces of the conveyor and the respective electromagnetic assemblies. This embodiment may include longitudinally spaced rollers 80 disposed on opposite sides of arm 134 .
Electromagnet coils 136 , 146 of speed sensors 48 a , 50 a are connected to associated amplifiers 160 , 162 of a controller 52 a (FIG. 10) for suitably energizing the electromagnets. Hall sensors 102 , 103 of the respective speed sensors are connected through associated signal conditioning electronics 116 , 120 to motor controller 118 a , which controls operation at motors 40 , 44 to maintain desired constant linear speed at the conveyors, as previously described. Thus, the embodiment of FIGS. 7-10 replaces the permanent magnet 96 in the embodiment of FIGS. 2-6 with an associated electromagnet, and positions electromagnets both above and below the conveyor for enhanced sensitivity.
There has thus been disclosed a glass machine system, and particularly a glassware linear conveyor speed sensor, that fully satisfies all of the objects and aims previously set forth. The invention has been disclosed in conjunction with presently preferred embodiments thereof, and a number of modifications and variations have been discussed. Other modifications and variations will readily suggest themselves to persons of ordinary skill in the art in view of the foregoing description. The invention is intended to embrace all such modifications and variations as fall within the spirit and broad scope of the appended claims. | A glass machine system in accordance with presently preferred embodiments of the invention includes a glassware manufacturing machine for manufacturing articles of glassware and transferring the articles to a linear conveyor, at least one linear chain conveyor for receiving and transporting such articles from the machine, and a speed sensor for monitoring linear speed of the conveyor. The speed sensor includes a magnetic energy source, a magnetic energy sensor and bracketry mounting the source and sensor adjacent to the conveyor. The chain conveyor teeth affect magnetic energy coupling between the source and sensor as the conveyor passes adjacent to the sensor. Electronic circuitry is responsive to signals from the sensor for determining linear speed of the conveyor and maintaining a constant linear speed at the conveyor. | 2 |
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made under DOE Contract DE-FC22-95PC93052 and is subject to government rights arising therefrom.
BACKGROUND OF THE INVENTION
The present invention is a diesel fuel composition for an increased cetane number vis-a-vis conventional diesel fuel compositions and generally comprises one or more compounds selected from the dialkoxy alkane (DAAK) chemical family.
A diesel fuel is a broad class of petroleum products which includes distillate or residual materials (or blends of these two) from the refining of crude oil and which is used in compression ignition or diesel engines. The two primary criteria used to define diesel fuel are distillation range (generally between 150° and 380° C. or 302° and 716° F.) and specific gravity range (between 0.760 and 0.935 at 59° F. or 15° C.). The properties of diesel fuel greatly overlap those of kerosene, jet fuels, and burner fuel oils and thus all these products are generally referred to as intermediate distillates.
The cetane number of a diesel fuel is roughly analogous to the octane number of gasoline. A high cetane number indicates the ability of a diesel engine fuel to ignite quickly after being injected into the combustion cylinder.
Prior to reviewing the prior art with regard to diesel fuel compositions comprising DAAKs, it is worth noting some background information on the DAAK chemical family, including alternative nomenclature. DAAKs can be represented as R--O--X--O--R where R=C n H 2n+1 , O=oxygen and X=C m H 2m . Probably the best known compound in this family is dimethoxy methane (DMMT) where n and m in the above formula are equal to 1 and which is more commonly referred to as methylal. Other compounds in this family which are the subject matter of the present invention include dimethoxy ethane (DMET) where n is again equal to 1 but m is equal to 2, and dimethoxy propane (DMPP) where n is again equal to 1 but m is equal to 3. Other common nomenclature for DAAKs is alkylene glycol dialkyl ethers. Similarly, other common nomenclature for DMMT, DMET and DMPP is, respectively, methylene glycol dimethyl ether, ethylene glycol dimethyl ether and (as it relates to 1,2 DMPP) propylene glycol dimethyl ether.
DMMT is taught as a cetane improving additive for diesel fuel. Specifically, a study by Southwest Research Institute for the US Department of Energy (as reported in OSTI as DE94006949, June 1994) teaches that DMMT (referred to as methylal in this study) may have possible use as a diesel fuel additive/replacement because it reduces smoke emissions and because it has a favorable cetane number. A repeat test by Southwest Research Institute on the Applicant's behalf, however, indicates that DMMT has a cetane number of only 29 (as compared to a cetane number of approximately 40 for conventional diesel fuel) and is not a cetane improver when added to diesel fuel.
DMET is taught as a diesel fuel additive in small (less than 5 weight %) concentrations for the purpose of soot and smoke suppression. See for example U.S. Pat. No. 3,594,136, U.S. Pat. No. 3,594,140, U.S. Pat. No. 3,615,292 and GB Patent Specification 1,246,853. DMET was also studied as a possible soot reducing diesel fuel replacement by Beatrice et al. in a 1996 article in IMech E (C517/023/96) where it was noted that DMET has a cetane number of 98. One study by Southwest Research Institute as reported in the SAE Technical Paper Series (950250) also teaches DMET (which was referred to as ethylene glycol dimethyl ether and "monoglyme" in this study) as a diesel fuel additive at moderate concentrations, specifically at concentrations of 5.62 mass % (5.5 volume %) and 11.24 mass % (11.1 volume %). The purpose of adding DMET to diesel duel in this study was not for cetane improvement, however, but for the purpose of increasing the oxygen level of the diesel fuel so that the effect of oxygen level on emission levels could be determined. Although this study also adjusted the cetane number of the diesel fuel so that the effect of cetane number on emission levels could be similarly determined, the cetane improver additive was 2-ethylhexyl nitrate and not DMET. Any cetane improvement attributable to DMET in this study was inadvertent. This study did note that oxygenating the diesel fuel generally increased cetane number in proportion to the amount of DMET added. Applicant's testing, however, indicates that although DMET has a very high cetane number of 105, it is not a significant cetane improver when added to diesel fuel except at concentrations above approximately 25 volume %.
DMPP, and other DAAKs besides DMMT and DMET, are not taught as diesel fuels or additives thereto.
BRIEF SUMMARY OF THE INVENTION
The present invention is a diesel fuel composition for an increased cetane number vis-a-vis conventional diesel fuel compositions and generally comprises one or more compounds selected from the dialkoxy alkane (DAAK) chemical family. In a preferred embodiment of the present invention, the diesel fuel composition consists of moderate amounts of dimethoxy propane (DMPP) and dimethoxy ethane (DMET) blended into a conventional diesel fuel.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a diesel fuel composition for increased cetane number comprising one or more compounds selected from the group consisting of:
(a) dimethoxy propane (DMPP) as represented by CH 3 --O--C 3 H 6 --O--CH 3 ;
(b) dimethoxy ethane (DMET) as represented by CH 3 --O--C 2 H 4 --O--CH 3 wherein the concentration of the DMET in said diesel fuel composition is either:
(i) any concentration less than 100 volume % if the DMET is used in combination with DMPP in said diesel fuel composition; or
(ii) any concentration greater than or equal to 15 volume % but less than 100 volume % if the DMET is not used in combination with DMPP in said diesel fuel composition; and
(c) in addition to DMPP and DMET, other dialkoxy alkanes as represented by R--O--X--O--R where R=C n H 2n+1 , and X=C m H 2m , and where n is at least 1 and m is at least 2.
In a typical embodiment of the present invention, the diesel fuel composition further comprises a conventional diesel fuel consisting of a hydrocarbon distillate having a boiling point between 150° C. and 380° C. (302° F. and 716° F.).
DMPP is the most promising individual compound of the present invention in terms of cetane improvement when blended with a conventional diesel fuel. Table 1 below illustrates that 1,2-DMPP has a cetane number of 109 and, when blended with a conventional diesel fuel having a cetane number of 37 (Data 1a) or 52 (Data 1b), the cetane number of the resulting blend is significantly improved above 35 volume % and slightly improved below 35 volume %. (Applicants used a constant volume combustion apparatus to measure all cetane numbers reported herein).
TABLE 1______________________________________Volume % 1,2-DMPP Cetane Number______________________________________(Data 1a)0 3745 5050 5875 90100 109(Data 1b)0 5215 5625 6035 6445 7175 83______________________________________
DMET is a cetane improver when blended with a conventional diesel fuel but only at moderately high to high concentrations. Table 2 below illustrates that 1,2-DMET has a cetane number of 105 and, when blended with a conventional diesel fuel having a cetane number of 37 (Data 2a) or 46 (Data 2b), the cetane number of the resulting blend is significantly improved above 25 volume % and slightly improved below 25 volume %.
TABLE 2______________________________________Volume % 1,2-DMET Cetane Number______________________________________(Data 2a)0 3745 6950 7175 76100 105(Data 2b)0 4615 4725 5035 5945 79______________________________________
Surprisingly and unexpectedly, the combination of DMPP and DMET is a synergistic cetane improver when blended with a conventional diesel fuel. Table 3 below illustrates that when 12.5 volume % 1,2-DMPP and 12.5 volume % 1,2-DMET are blended with 75 volume % of a conventional diesel fuel, the cetane number of the resulting blend is significantly improved to 51. This is unexpected since this percentage increase is much greater than the sum of the parts increases that could be expected based on the data in Tables 1 and 2.
TABLE 3______________________________________Volume % 1,2-DMPP Volume % 1,2-DMET Cetane Number______________________________________0 0 39.412.5 12.5 51______________________________________
DMPP and DMET can be prepared from propylene oxide and ethylene oxide respectively. DMET can also be advantageously prepared by the oxidative coupling of dimethyl ether (DME). The other reaction products when starting with DME include the liquid reaction products methanol and DMMT which, along with the liquid reaction product DMET, can easily be separated from the gaseous reaction products of methane, C 2 and C 3 hydrocarbons, CO, CO 2 and non-reacted DME. The relative concentrations of the three liquid reaction products can be varied depending upon the catalyst type, gas hourly space velocity, reaction temperature, reaction pressure and molar ratio of DME/oxygen feed. In general, these variables should be selected to minimize the amount of methanol and DMMT produced since methanol and DMMT have low cetane numbers of 5 and 29 respectively and since, once produced, are difficult to separate from DMET.
The skilled practitioner will appreciate that to be useful the diesel fuel composition of the present invention must result in one phase. Fortunately, blends of DMPP, DMET and conventional diesel fuel can be varied over a wide range and remain miscible (ie remain in one phase). Blends of DMPP and conventional diesel fuel are miscible at concentrations all the way up to 90 volume % DMPP. Likewise, blends of DMET and conventional diesel fuel are miscible at concentrations all the way up to 90 volume % DMET. It should be noted, however, that when methanol is a component of the diesel fuel composition, two phases generally result when the methanol component is greater than 10 volume % and thus methanol should be kept below this limit. The diesel fuel used in generating this miscibility data was #1 diesel fuel having low sulfur, no dye and not a winter formulation.
In addition to improved cetane number, another benefit of the present invention's diesel fuel compositions vis-a-vis conventional diesel fuel compositions is improved cold starting properties which is a function of the fact that the DAAK compounds of the present invention have an increased volatility vis-a-vis conventional diesel fuel.
Finally, it should be noted that given the overlap in properties between diesel fuel and other intermediate distillate fuels such as kerosene, jet fuels, and burner fuel oils, the DAAK compounds of the present invention may also have utility as replacements or additives for such other intermediate distillate fuels. | A diesel fuel composition is set forth for an increased cetane number vis-a-vis conventional diesel fuel compositions. The composition generally comprises one or more compounds selected from the dialkoxy alkane (DAAK) chemical family. In a preferred embodiment of the present invention, the diesel fuel composition consists of moderate amounts of dimethoxy propane (DMPP) and dimethoxy ethane (DMET) blended into a conventional diesel fuel. | 2 |
BACKGROUND OF THE INVENTION
[0001] Revenue for Internet companies is often driven by advertising, which is typically paid out based on a network interaction (e.g., a click) on an advertisement. However, sometimes a network interaction is not legitimate—for example, a botnet may be developed to cause network interactions on an advertisement. Illegitimate network interactions lead to inappropriate payments by advertisers and inappropriate payments to publishers. Advertisers and publishers need to be informed of legitimate and illegitimate network interactions in order to determine appropriate payments. However, the information provided may release information that helps illegitimate network interaction creators to mask their activity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0002] Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings.
[0003] FIG. 1 is a block diagram illustrating an embodiment of a system for rating a network interaction.
[0004] FIG. 2 is a flow diagram illustrating an embodiment of a process for rating a network interaction.
[0005] FIG. 3 is a flow diagram illustrating an embodiment of a process for receiving a data regarding a network interaction.
[0006] FIG. 4 is a flow diagram illustrating an embodiment of a process for determining a rating based on data.
[0007] FIG. 5 is a flow diagram illustrating an embodiment of a process for determining a reason code.
[0008] FIG. 6 is a block diagram illustrating an embodiment of providing a rating and reason code.
[0009] FIG. 7 is a block diagram illustrating an embodiment of providing a reason code.
[0010] FIG. 8 is a block diagram illustrating an embodiment of providing a reason code.
DETAILED DESCRIPTION
[0011] The invention can be implemented in numerous ways, including as a process, an apparatus, a system, a composition of matter, a computer readable medium such as a computer readable storage medium or a computer network wherein program instructions are sent over optical or communication links. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. A component such as a processor or a memory described as being configured to perform a task includes both a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. In general, the order of the steps of disclosed processes may be altered within the scope of the invention.
[0012] A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured.
[0013] Providing a rating and/or a reason code for a network interaction is disclosed. A rating is provided to an advertiser and/or a publisher so that an understanding can be determined of a payment between the advertiser and the publisher. However, the advertiser and/or publisher may desire more knowledge regarding one or more network interactions and why the rating was determined as it was. On the other hand, if too much information is provided as to why the rating was determined as it was, then it may be possible to fool the rating system. A reason code is provided to provide a reason for the rating of a network interaction. The reason code provides some information to the advertiser and/or publisher without indicating the exact nature of which information affects a rating or how that information affects a rating. This provides evidence that the rating is legitimate to the advertiser and/or publisher while still protecting the specifics of the rating system against would-be fraud of the rating system.
[0014] FIG. 1 is a block diagram illustrating an embodiment of a system for rating a network interaction. In the example shown, computer 100 is used by a user for accessing a web page on server 106 . In various embodiments, server 106 is associated with an advertising network or an advertiser. Computer 100 is able to communicate with network 102 . In various embodiments, network 102 comprises one or more of the following: the Internet, a local area network, a wide area network, a wired network, a wireless network, or any other appropriate network. Server 106 can be accessed from network 102 via firewall 104 and local area network (LAN) 105 . Edge appliance 108 is able to monitor traffic to and from server 106 and is connected to LAN 105 . In various embodiments, monitoring comprises detecting in hardware the network traffic or the network interactions to be monitored, detecting in real-time network traffic, capturing data in real-time, analyzing data in real-time, triggering real-time queries or forensics of Internet protocol (IP) addresses/network topology/routing tables/preferred paths, detecting layer 3 through layer 7 data from the monitored traffic, monitoring Ethernet traffic, or any other appropriate monitoring of network traffic. Edge appliance 108 is able to store information on storage device 110 . In some embodiments, edge appliance 108 monitors traffic to and from server 106 by being between server 106 and LAN 105 by receiving and forwarding all traffic between network 102 and server 106 . In this situation, all traffic is received and forwarded without substantially affecting network traffic, without substantially affecting a transaction involving the network traffic, and/or with little delay (e.g., less than 2 milliseconds of delay) for the process of receiving and forwarding to make it appear as if the device is essentially not present.
[0015] In some embodiments, edge appliances can also be used to monitor traffic at other points in the network other than in front of or just beside a server - for example, on a trunk line, an internet service provider network, an advertising network, or any other appropriate traffic site.
[0016] In some embodiments, server 106 reports information regarding the network interaction. For example, a software monitor records information regarding a network interaction including a time, an IP originating address, a domain, a country, an operating system, user agent, referrer, stem portion of referrer (“referrer-stem”, query portion of referrer (“referrer-query”), referrer query length, search key word, search key word frequency, etc. The software monitor forwards the information regarding the network interaction to model server 112 or analytics server 116 as appropriate to enable the use of the information to rate the network interaction. In some embodiments, where server 106 reports information regarding the network interaction, edge appliance 108 is not present.
[0017] Edge appliance 108 is able to communicate with model server 112 . Edge appliance 108 periodically transmits reports and receives models from model server 112 . Model server 112 can store information on storage device 114 . Model server 112 forwards reports from edge appliance 108 to analytics server 116 and forwards models from analytics server 116 to edge appliance 108 . In some embodiments, there are a plurality of model servers and a plurality of edge appliances, where an analytics server is able to support the communications with a plurality of model servers, and a model server is able to support the communications with a plurality of edge appliances. In some embodiments, scalability is achieved using a plurality of model servers.
[0018] Models are used by edge appliance 108 to calculate a preliminary score in real-time or quasi-real-time for detected network interactions. A preliminary score can be based on information associated with detected network interaction(s) as well as on stored parameters or models received from a model server or an analytics server such as model server 112 and analytics server 116 , respectively.
[0019] Analytics server 116 stores report information to storage device 120 which acts as a data warehouse for the report information. Reports web server 122 can build reports based on the data stored in storage device 120 . Network operations server 118 monitors the health and status of the system for analyzing network interactions including model server 112 , analytics server 116 , reports web server 122 , and edge appliance 108 . Network operations server 118 is able to communicate with each of the system hardware units including model server 112 , analytics server 116 , reports web server 122 , and edge appliance 108 (in some cases directly or via the Internet with edge appliance 108 and in some cases via the Internet, through firewall 104 , and via LAN 105 ).
[0020] In various embodiments, edge appliance 108 monitors network traffic on a local network that is separated from other networks (e.g., the Internet) by a firewall, receives network traffic from a local network and transmits the network traffic to a web server, receives network traffic from a local network that also transmits the network traffic to a web server, or receives network traffic from any other point or between any other two points appropriate for monitoring network traffic.
[0021] In various embodiments, model server 112 , analytics server 116 , network operations server 118 , and reports web server 122 are implemented in separate servers or computer hardware units, in a single server or computer hardware unit, or any combination of separate and combined servers or computer hardware units.
[0022] In various embodiments, different combinations of model server 112 , analytics server 116 , and reports web server 122 are used to determine a rating and/or a reason code for a network interaction.
[0023] FIG. 2 is a flow diagram illustrating an embodiment of a process for rating a network interaction. In the example shown, in 200 a data is received regarding a network interaction. In 202 , a rating is determined based on the data. In 204 , a reason code is determined, where the reason code indicates a reason for the rating. In 206 , the rating and the reason code are provided for the network interaction.
[0024] FIG. 3 is a flow diagram illustrating an embodiment of a process for receiving a data regarding a network interaction. In some embodiments, the process of FIG. 3 is used to implement 200 of FIG. 2 . In the example shown, in 300 referrer information is received. In 302 , search key word information is received. In 304 , search key word frequency information is received. In 306 , user agent information is received. In 308 , referrer-query length information is received. In 310 , user agent operating system information is received. In 312 , originating IP address information is received. In 314 , time and/or date information is received. In 316 , conversion information is received. In 318 , originating country information is received.
[0025] FIG. 4 is a flow diagram illustrating an embodiment of a process for determining a rating based on data. In some embodiments, the process of FIG. 4 is used to implement 202 of FIG. 2 . In the example shown, in 400 a first data is selected. In 402 , it is determined if the selected data affects the rating. If the selected data affects the rating, then in 404 , the rating is updated. In some embodiments, prior data is considered when updating a rating. For example, previous network interactions and the data regarding timing, sources, routes, countries, domains, IP addresses, conversions, etc. can influence the rating update. In 406 , a record of the data and the affect the data had on the rating is stored, and control passes to 408 . If the selected data does not affect the rating, control passes to 408 . In 408 , it is determined if there is more data. If there is more data, then in 410 a next data is selected, and control passes to 402 . If there is no more data, then the process ends. In various embodiments, the rating is summarized as a positive rating (e.g., ‘+’ or graded positive rating ‘++’), a neutral rating, a negative rating (e.g., ‘−’ or a graded negative rating ‘−−−’), a fraudulent rating, a conversion rating (e.g., likely to convert), a letter rating (e.g., A, B, AA, B+, etc.), a number ranking (e.g., 1, 2, etc.), or any other appropriate rating.
[0026] In some embodiments, data received regarding a network interaction indicates that the network interaction is one of many recent visits from the same IP address, the rating process rates the network interaction such that the rating would decrease, whereas data received regarding a network interaction that indicates that the network interaction is one of many recent visits from the same IP address during which conversions and/or purchases have been made, the rating for the network interaction would increase. In this example, the rating system has ratings that increase for a better/desirable network interaction and decrease for worse/undesirable network interactions.
[0027] In various embodiments, a rating calculation is based on empirical and/or statistical models of network interactions and outcomes (i.e., conversions and/or purchases). In various embodiments, a rating calculation is based on a series of business rules which in turn rely on statistical models, do not rely of statistical models, rely on empirical models, or any other appropriate basis for ratings.
[0028] FIG. 5 is a flow diagram illustrating an embodiment of a process for determining a reason code. In some embodiments, the process of FIG. 5 is used to implement 204 of FIG. 2 . In the example shown, in 500 a first record is selected of data and the affect the data had on the rating. In 502 , it is determined if the selected record is associated with a reason code. If the record is associated with a reason code, then in 504 the reason code and affect on the rating is stored in a list. In some embodiments, multiple records (and hence multiple data) are associated with a given reason code. In 506 , the list of reason codes is ordered by affect on the rating, and control passes to 508 . If the record is not associated with a reason code, then control passes to 508 . In 508 , it is determined if there are more records of data and the affect the data had on the rating. If there is/are more record(s), then in 510 a next record is selected, and control passes to 502 . If there are no more records, then the process ends.
[0029] In some embodiments, the list is sorted after processing all records. In some embodiments, the list is not sorted.
[0030] In some embodiments, a reason code list changes over time to reflect new information appropriate for positive or negative affects on ratings.
[0031] In various embodiments, a reason code comprises one of the following items: self-identified robot, crawler, spider; repeat adclick; double click on ad; blank referrer; referred from major search engine; not referred from major search engine; rare search term; user_agent not Mozilla; referrer-query not provided; referrer-query too long; unusual operating system; no visits from this IP in last 24 hours; never seen this IP before; visits have too few page requests from this IP recently; visits too brief from this IP recently; recent visits from this IP; using rare HTTP protocol; never seen this domain before; too many adclicks from this domain recently; previous requests too recent from this IP; blank user agent; lack of recent conversions from this IP; too few recent conversions from this IP; rare browser; lack of recent visits from this country; lack of recent conversions from this country; too few recent conversions from this country; Canadian adclick; Foreign adclick; too many recent adclicks for this IP; IP Forensics; or any other appropriate reason code.
[0032] In some embodiments, a reason code is provided using a numeric or alphanumeric code. For example, a self-identified robot, a self-identified crawler, or a self-identified spider is provided by providing a single numeric code (e.g., ‘2’).
[0033] FIG. 6 is a block diagram illustrating an embodiment of providing a rating and reason code. In some embodiments, FIG. 6 is provided on execution of 206 of FIG. 2 . In the example shown, a tally of ad clicks 600 includes a reporting of total number of ad clicks 602 , invalid ad clicks 604 , valid ad clicks 606 , and ad click statistic 608 . Total number of ad clicks 602 reports the total number of network interactions with respect to an advertisement during the period of time 618 . A rating of invalid for clicks is provided by invalid ad clicks 604 . Invalid ad clicks 604 reports network interactions with respect to an advertisement during period of time 618 . For example, reason code 610 (i.e., self-identified robot, crawler, spider), reason code 612 (i.e., repeat ad clicks), and reason code 614 (i.e., double clicks on ad). Other reason codes are aggregated into a single reason code in this report 616 titled ‘Other Invalid Ad Clicks’. A rating of valid for clicks is provided by valid ad clicks 606 . Click statistic 608 which provides a calculated statistic based on the findings regarding network interactions.
[0034] FIG. 7 is a block diagram illustrating an embodiment of providing a reason code. In some embodiments, FIG. 7 is provided on execution of 206 of FIG. 2 . In the example shown, illustrative examples of the fifty top reason codes for invalid clicks 700 includes ordered list of reason codes 702 , count 704 , and illustrative example 706 . Ordered list of reason codes 702 includes a list of up to four reason codes for an invalid rating of a network interaction. The reason codes are ordered in such a way that the left most reason code had the most affect on the rating, and proceeding to the right the reason codes had less and less affect on the rating. In some cases there are not four codes that contributed to the rating, and in these cases there are blank spaces in the ordered list of reason codes 702 . Count 702 indicates the number of network interactions associated with the reason code list to its left as relevant reason code combinations used for rating the network interaction. Illustrative example 706 provides information for one example of a network interaction with the reason code combination. Illustrative example 706 provides an originating IP address of the network interaction, a date/time, a country of origin, and an IP domain name.
[0035] FIG. 8 is a block diagram illustrating an embodiment of providing a reason code. In some embodiments, FIG. 8 is provided on execution of 206 of FIG. 2 . In the example shown, top two reason codes for an invalid network interaction 812 shows a pie chart illustrating the percentage occurrence of a reason code or group of reason codes being in the top two reason codes. The pie chart includes reason codes or reason code groups user behavior 800 , click velocity 802 , domain or geography 804 , machine 806 , network forensics 808 , and route to site 810 . User behavior 800 includes reason codes such as recent visits from this IP; visits too brief from this IP recently; visits have too few page requests from this IP recently; too few recent conversions from this IP; and lack of recent conversions from this IP. Click velocity 802 includes reason codes such as too many recent adclicks for this IP and previous requests too recent from this IP. Domain or geography 804 includes reason codes such as too few recent conversions from this country; lack of recent conversions from this country; lack of recent visits from this country; too many adclicks from this domain recently; never seen this domain before; Foreign adclick; and Canadian adclick. Machine 806 includes reason codes such as referrer-query too long; blank user agent; referrer-query not provided; blank referrer; rare browser; using rare HTTP protocol; unusual operating system; and user_agent not Mozilla. Network forensics 808 includes reason codes such as IP Forensics. Route site 810 includes reason codes such as rare search term; not referred from major search engine; and referred from major search engine.
[0036] In some embodiments, reason code groups change over time as new reason codes are added and removed.
[0037] Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative and not restrictive. | Providing a reason code for a network interaction is disclosed. One or more data regarding a new incoming network interaction originated from a third party device over a network is received. A rating of the network interaction is determined based at least in part on the one or more data regarding the network interaction. A reason code is determined. The reason code indicates a reason for the rating. The reason code for the network interaction is provided. | 6 |
REFERENCE TO PRIORITY DOCUMENT
This application claims priority of co-pending U.S. Provisional Patent Application Ser. No. 60/798,111 filed May 4, 2006. Priority of the aforementioned filing date is hereby claimed and the disclosure of the Provisional patent application is hereby incorporated by reference in its entirety.
BACKGROUND
Disclosed herein is a curtain rod having an integrated bracket assembly.
A popular form of curtain rod comprises a generally straight rod member. The rod member typically has a plurality of rings that are slidably mounted to support curtains, draperies or the like. In this manner, the rod can support the curtains in a suspended state over a window or other structure.
In order to hang the curtain rod from a wall, one more brackets is typically attached to the rod. The brackets are typically fixed to the wall or woodwork surrounding the window. The plurality of brackets extend outward from the wall and provide, for example, a surface on which the curtain rod rests. The brackets can have various structures. For example, the brackets can be hook shaped such that they receive and support the curtain rod on the wall. The brackets can also be annular or ring-shaped such that the brackets surround the curtain rod. In any event, the brackets are typically visible from the front and contribute to an interrupted appearance of the curtain rod's profile.
SUMMARY
In view of the foregoing, there remains a need for a curtain rod assembly having an integrated supportive bracket providing a seamless profile when viewed from the front.
In one aspect, there is disclosed a curtain rod assembly, comprising: an elongated curtain rod having a first end and a second end, the rod extending along a longitudinal axis; a bracket having a base adapted to be secured to a wall and a shaft that extends outwardly from the base for coupling to the curtain rod, wherein the shaft protrudes into the curtain rod along a direction transverse to the longitudinal axis, the bracket adapted to support the curtain rod from a wall; and a fastener that protrudes into the curtain rod along a direction substantially parallel with the longitudinal axis, wherein a distal end of the fastener engages the shaft of the bracket to retain the shaft within the curtain rod.
In another aspect, there is disclosed a curtain rod assembly, comprising: an elongated curtain rod having a first end and a second end, the rod extending along a longitudinal axis; a bracket adapted be secured to a wall and to support the curtain rod from the wall, the bracket having an elongated portion that couples to the curtain rod, wherein the elongated portion protrudes into the curtain rod along a direction transverse to the longitudinal axis; and a fastener that protrudes into the curtain rod along a direction substantially parallel with the longitudinal axis, wherein a distal end of the fastener engages the shaft of the bracket to retain the shaft within the curtain rod.
Other features and advantages should be apparent from the following description of various embodiments, which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of one embodiment of a curtain rod assembly;
FIG. 2 shows an exploded view of the curtain rod assembly of FIG. 1 ;
FIG. 3A shows a perspective view of the curtain rod of FIG. 1 ;
FIGS. 3B and 3C show cross-sectional views of the curtain rod of FIG. 3A taken along lines B-B and C-C, respectively;
FIG. 4A shows a cross-sectional view of the curtain rod assembly of FIG. 1 taken along lines A-A;
FIG. 4B shows a cross-sectional view of the curtain rod assembly of FIG. 1 taken along lines B-B;
FIG. 4C shows a top plan view of the curtain rod assembly of FIG. 1 taken along circle C;
FIG. 5 shows a top plan view of another embodiment of a curtain rod assembly.
DETAILED DESCRIPTION
FIG. 1 shows a perspective view of one embodiment of a curtain rod assembly 100 . Only one end of the curtain rod assembly is shown in the figure, but it should be appreciated that the opposite end of the curtain rod assembly can be a mirror image of what is shown in FIG. 1 .
FIG. 2 shows an exploded view of the curtain rod assembly 100 of FIG. 1 , which includes a rod 105 , an end-piece 110 and a bracket 115 . The rod 105 is an elongated member, such as a substantially hollow tube. The rod can be entirely hollow or only partially hollow. The hollow interior of the rod 105 is capped at each end by a connector element 101 . The end-piece 110 attaches to the rod 105 at each end by way of the connector element 101 . The rod 105 also has an aperture 103 near each of its ends that is in communication with its hollow interior. The bracket 115 inserts through the aperture 103 of the rod 105 and is fixed in place by the end-piece 110 and a fastener 112 . This integration of the bracket 115 within the rod 105 by the end-piece 110 and fastener 112 imparts a seamless profile to the curtain rod assembly 100 as described in more detail below.
The end-piece 110 , such as a decorative finial, connects to each end of the rod 105 by way of the fastener 112 . The end-piece need not be a decorative finial. The fastener 112 can be, for example, a double-ended screw and provides a connection between the end-piece 110 and the rod 105 . This connection can be by way of the connector element 101 , as described in more detail below. The fastener 112 can be of conventional gauge and thread count known in the art. The fastener 112 can be part of the end-piece 110 as shown in the curtain rod assembly embodiment of FIG. 2 or the fastener 112 can be independent of the end-piece 110 .
As described above, the supportive bracket 115 is integrated within the rod 105 by interaction with the end-piece 110 and fastener 112 . This can impart a visually seamless profile to the curtain rod assembly 100 such that the bracket 115 appears to be an integral piece with the rod. The bracket 115 as shown in FIG. 2 includes a wall coupler, such as a flat base 119 , and an elongate shaft 117 . The base 119 includes one or more holes 125 through which the base 119 of the bracket 115 can be fixedly attached to the wall or woodwork around the window such as by screws, nails and the like. Alternately, the base 118 cab be attached using glue. The elongate shaft 117 extends outwardly away from the base 119 and inserts into the aperture 103 of the rod 105 at its opposite end, to be described in more detail below. The shaft 117 and the aperture 103 are of corresponding diameter and size such that when the shaft 117 is inserted through the aperture 103 there is very little play or movement between the two. This provides for a stable connection between the rod 105 and the bracket 115 .
As best shown in FIGS. 3A-3C , the connector element 101 is located inside the hollow interior of the rod 105 at or near each end of the rod 105 . The connector element 101 can be fixedly attached to the hollow interior of the rod 105 , such as by a weld or similar fixation method. The connector element 101 can also be integrally formed with the rod 105 . The connector element 101 has a longitudinal, threaded passage 107 , which accommodates the fastener 112 , and a transverse passage 108 , which aligns with the aperture 103 of the rod 105 . As described above, the fastener 112 attaches the end-piece 110 to the rod 105 by way of the connector element 101 .
FIGS. 4A , 4 B and 4 C illustrate one embodiment of the curtain rod assembly 100 . The end of the shaft 117 opposite the base 119 of the bracket 115 has a narrowed diameter such that it has the appearance of a pin 121 having a flange 123 . This end of the shaft 117 is inserted through the aperture 103 of the rod 105 such that the flange 123 may make contact with the wall of the connector element 101 opposite its entry point at the aperture 103 . The pin 121 spans the longitudinal passage 107 of the connector element 101 . Further, at least a portion of the shaft 117 is also inside the connector element 101 and thus, within the wall of the rod 105 . This gives a smooth, integrated appearance to the intersection of the bracket 115 and the rod 105 . The shaft 117 of the bracket 115 is held inside the rod 105 through contact with the fastener 112 as described in more detail below.
The bracket 115 can be retained within the rod 105 in various manners. In the embodiment best shown in FIG. 4C , the shaft 117 is inserted through the aperture 103 and the transverse passage 108 of the connector element 101 until the flange 123 contacts the opposing wall of the connector element 101 and the pin 121 spans the longitudinal passage 107 of the connector element 101 . The length of the pin 121 between the flange 123 and the end of the shaft 117 is sized proportionately to receive the diameter of the end of the fastener 112 . The fastener 112 is threaded through the longitudinal passage 107 of the connector element 101 and contacts the pin 121 spanning the passage 107 . The end of the fastener 112 is contacted on one side by the flange 123 and on the other side by the shaft 117 . The sandwiching of the end of the fastener 112 between the flange 123 and the shaft 117 holds the bracket 115 inside the rod 105 and helps to prevent slippage of the bracket 115 out of the rod 105 .
FIG. 5 shows another embodiment of the curtain rod assembly 500 including a bracket 115 having a shaft 517 of substantially uniform diameter. As described with respect to the first embodiment, this embodiment includes a connector element 501 that has a longitudinal passage 507 , which accommodates the fastener 512 , and a transverse passage 508 , which aligns to accommodate the shaft 517 . The shaft 517 is inserted through the transverse passage 508 of the connector element 501 until the end of the shaft 517 contacts the opposing wall of the connector element 501 . In contrast to the first embodiment, the shaft 517 of this embodiment is substantially uniform in diameter along its entire length and does not include a flange. The end of the shaft 517 is held inside the rod 505 by virtue of the threaded fastener 512 contacting the end of the shaft 517 .
Generally, each component of the curtain rod assembly can be manufactured from metal stock, but they can also be of other materials such as plastic or wood. The surface of the components can be provided with a protective paint surface. The components generally are constructed of matching materials and finished in matching surfaces to provide them with a uniform appearance. However, the materials and finishing of the components need not be identical.
It should be understood by those skilled in the art that the particular embodiments of the curtain rod assembly presented herein are by way of illustration only, and are meant to be in no way restrictive; therefore, numerous changes and modifications may be made, and the full use of equivalents resorted to, without departing from the spirit or scope of the invention as outlined in the appended claims. | A curtain rod assembly includes one or more support members, such as brackets, that are configured to support a curtain rod from a wall. The support member include a coupler portion that provides a seamless and flush interface between the support member and the rod. | 8 |
TECHNICAL FIELD
[0001] This application relates to security in a virtual computing environment, and more particularly, to enabling guest operating systems to operate a security platform application while accessing a virtual computing environment.
BACKGROUND
[0002] Security tools are often hacked by malicious software operating on an infected computing device. An attacker may try to uninstall the security tool, bypass its protection mechanisms, or render it useless by removing portions of its required resources. In order to reduce the likelihood of such attacks, security tools may be utilized which include a protecting kernel resident module that guarantees the device integrity as well as the integrity of the system resources being utilized. However, an attacker who gained sufficient privileges (i.e., root or administrative depending on the operating system) can attack kernel modules as well.
[0003] Various security APIs implement a security channel to enable a ‘security virtual machine’, however, this approach does not provide protection against certain attacks, such as with respect to a guest virtual machine (VM). Also, hypervisor components are generally not included to assure protection of the guest VMs.
[0004] Certain previous approaches to implementing security measures include a number of guest OSs operating on one or more hypervisors. Such approaches focus on detecting errors in the running guest OSs, deciding whether the fault is local to a single OS or to others and selecting corrective actions accordingly. Such actions may include a restart of a single OS or a migration to a different hypervisor if the errors are reported from two or more guests, thus pointing to a fundamental problem (i.e. not local to a single OS).
[0005] Other approaches include a distributed and coordinated security system providing intrusion detection and prevention for virtual machines (VMs) operating in a virtual server. This may include passing a packet stream through an associated networking driver of a virtualization platform and filtering the packet stream in a security platform of the guest virtual machine. However, this approach fails to identify an attack on the guest OS or vulnerabilities exploited through legitimate traffic. The approaches to detecting removal of security agents operating on guest operating systems are limited in scope and could be potentially overcome by attackers seeking access to virtual resources.
SUMMARY
[0006] Hypervisors and guest operating systems/virtual machines communicate in virtual environments to enable applications and other services. Security measures are always a concern in implementing a secure environment. One example may include identifying a session initiation request from a guest operation system at a hypervisor component of a server. Also, the example may include receiving periodic messages from the guest operating system, and establishing and maintaining a session and connection between the hypervisor and the guest operating system responsive to receiving the periodic messages from the guest operating system.
[0007] Another example embodiment of the present application may include an apparatus that provides a processor configured to perform at least one of identify a session initiation request from a guest kernel module at a hypervisor component of a server, and initialize a session between the guest kernel module and the hypervisor component. Also, a receiver configured to receive periodic messages from the guest kernel module, and where the processor is further configured to maintain the session between the hypervisor component and the guest kernel module responsive to the periodic messages received from the guest kernel module.
[0008] Another example embodiment may include a non-transitory computer readable storage medium configured to store instructions that when executed cause a processor to perform at least one of identifying a session initiation request from a guest kernel module at a hypervisor component of a server, initializing a session between the guest kernel module and the hypervisor component, receiving periodic messages from the guest kernel module, and maintaining the session between the hypervisor component and the guest kernel module responsive to receiving the periodic messages from the guest kernel module.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 illustrates a configuration diagram of a virtual environment according to an example embodiment of the present application.
[0010] FIG. 2A illustrates a system communication diagram of a data communication between a guest operating system and a hypervisor according to an example embodiment of the present application.
[0011] FIG. 2B illustrates a system communication diagram of a data communication between an administrator and a hypervisor management component and guest kernel module according to an example embodiment of the present application.
[0012] FIG. 3 illustrates a logic flow diagram of a security procedure within the virtual environment according to an example embodiment of the present application.
[0013] FIG. 4 illustrates a system configuration configured to perform one or more of the example embodiments of the present application.
[0014] FIG. 5 illustrates an example network entity device configured to store instructions, software, and corresponding hardware for executing the same, according to example embodiments of the present application.
[0015] FIG. 6 illustrates another example configuration diagram of a virtual environment for multiple heartbeat requirements being assigned according to another example embodiment of the present application.
[0016] FIG. 7 illustrates a system communication diagram of a data communication between a plurality of guest operating systems and a hypervisor according to another example embodiment of the present application.
[0017] FIG. 8 illustrates a microvisor management configuration which operates with heartbeat messaging criteria according to example embodiments.
[0018] FIG. 9 illustrates a system signaling configuration of the microvisor configuration according to example embodiments.
DETAILED DESCRIPTION
[0019] It will be readily understood that the components of the present application, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of a method, apparatus, and system, as represented in the attached figures, is not intended to limit the scope of the application as claimed, but is merely representative of selected embodiments of the application.
[0020] The features, structures, or characteristics of the application described throughout this specification may be combined in any suitable manner in one or more embodiments. For example, the usage of the phrases “example embodiments”, “some embodiments”, or other similar language, throughout this specification refers to the fact that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. Thus, appearances of the phrases “example embodiments”, “in some embodiments”, “in other embodiments”, or other similar language, throughout this specification do not necessarily all refer to the same group of embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0021] In addition, while the term “message” has been used in the description of embodiments of the present application, the application may be applied to many types of network data, such as, packet, frame, datagram, etc. For purposes of this application, the term “message” also includes packet, frame, datagram, and any equivalents thereof. Furthermore, while certain types of messages and signaling are depicted in exemplary embodiments of the application, the application is not limited to a certain type of message, and the application is not limited to a certain type of signaling. In addition, the communication between the hypervisor(s), guest operating systems, guest kernel module(s) (GKM) and/or the hypervisor management components(s) (HMC) may include direct and/or indirect information sharing via a shared memory or other information sharing mechanism.
[0022] Example embodiments provide hypervisor and virtual machine guest operating system (OS) configurations with tamper detection for guest protection. An attack on a machine may be discovered through a sudden disconnect of a cryptographic heartbeat communication protocol. In operation, the heartbeat messages may suddenly stop being sent from the guest OS and received via the hypervisor due to removal of the guest kernel module (GKM). In such a scenario, when the GKM is completely removed it cannot report any kind of error voluntarily. Therefore, the heartbeat message detection and lack thereof serves to maintain integrity between a hypervisor and guest OS configuration.
[0023] Components of the hypervisor and the kernel modules in the guest OS will indicate whether there are additional components added by the hypervisor. Additionally, listing those components and communication channels between the hypervisor and the guest OS will indicate whether such communication between those entities is active. The hypervisor component is distinct from the guest OS infrastructure and may detect tampering of the guest OS security components and enforce any applicable anti-tampering protection policy.
[0024] FIG. 1 illustrates a virtual network diagram with various virtual components according to example embodiments. Referring to FIG. 1 , a virtual configuration 100 includes a hypervisor 120 as a fundamental virtual environment component which further includes a hypervisor management component (HMC) 122 . Another layer includes the guest operating system (OS) kernel 114 A and 114 B where a guest virtual machine can be identified and authenticated by the hypervisor 120 . The guest OSs 114 A and/or 114 B may receive a request to install guest kernel modules 118 A and 118 B, respectively, which include heartbeat protocol criteria including but not limited to the heartbeat message requirements (i.e., packet size) and/or specified frequency criteria (i.e., heartbeat message specifications and number per time interval). A guest OS user space 110 A, 110 B, 110 C, 110 D, etc., may then install an agent 112 A, 112 B, 112 C and/or 112 D as directed by the hypervisor so the heartbeat criteria can be established to begin updating the hypervisor 120 based on the frequency requirements, which may include one message per a specified time interval. The installation of the agent may be performed by the hypervisor by initiating the guest OS with the agent upon boot-up. Each instance of the guest OS may have its own agent.
[0025] The heartbeat protocol criteria may include a cryptographic heartbeat which is also provided when the guest OS 114 A, for example, begins to boot-up and is detected by the hypervisor 120 . A guest kernel module (GKM) 118 A, for example, is then installed and is provided with a randomly generated secret key for communication with the HMC 122 . The GKM 118 A stores the key securely in its private memory and obfuscates its location. The HMC 122 and the GKM 118 A communicate using a hypervisor provided communication mechanism such as event channels. Messages over the channel(s) are encrypted with an authenticated encryption protocol using the shared key provided at boot-up. The encryption protocol provides at least one of confidentiality, integrity, authenticity and a replay protection. The GKM 118 A uses the encrypted channel to send security events to the HMC 122 . The GKM 118 A periodically sends a heartbeat message over the encrypted channel according to a predetermined schedule. In one embodiment, the schedule can be set at any time. If the HMC 122 notices that the GKM 118 A stops sending heartbeats it can react by either attempting to revive the activity via the OS and/or alert a designated administrator and/or one or more computers (which include a processor and memory) in a network accessible by the administrator of a possible attack by the guest OS 114 A.
[0026] The information shared between virtual components of the virtual system may reside in shared memory spaces and other shared information locations which could be used to communicate between guest operating systems, hypervisors and other virtual system components. For example, XEN communication standards could be used to exchange data, which could be a 1-bit flag or pointer, to identify information stored in the shared memory spaces including but not limited to security threats alerts and heartbeat messages. The event channel may be the basis for utilizing 1-bit information sharing between virtual elements of the virtual environment.
[0027] Hypervisors can be used to ease the deployment and management of servers and workstations. As a hypervisor operates at a lower layer than a guest OS's kernel, an adversary executing in the context of a guest OS cannot affect the hypervisor. As a result, a security or protection tool that is assisted by hypervisor resident code is shielded from such attacks. A hypervisor resident component may be used for installing the protection tool within compatible guest OSs as well as processing output and guaranteeing normal operations. The security tool may be split into two components, executing at different layers with one component operating in the hypervisor which is safe but independent of the guest OS (i.e., processes, memory, file systems). The other component operates in the guest OS, which is more vulnerable but has visibility into the OS. The hypervisor 120 injects the guest OS component into the guest OS to mitigate attacks within the guest OS, which tries to remove security tools that can interfere with the attack's progress. For example, when the guest OS 114 A boots, the GKM 118 A is added. The HMC 122 and the GKM 118 A use a communication mechanism, such as event channels, through which regular, signed, heartbeat messages are sent and received. The communication protocol guarantees authenticity and resiliency. If the HMC 122 notices that the GKM 118 A stops sending heartbeats, it can respond by either reviving the guest in an OS specific manner and/or alerting the administrator as this inaction can be an indication of a malicious attack.
[0028] FIG. 2A illustrates a system configuration diagram 200 of a security communication session between a guest OS 210 and a hypervisor 212 according to example embodiments. Referring to FIG. 2A , the guest OS 210 may initiate communication via a virtual session setup operation 222 . The hypervisor 212 may receive a request to communicate 224 from the guest OS 210 and may respond by identifying 226 the guest OS via predefined credentials stored in memory identifying the guest OS 210 . An agent extension component 228 may then be forwarded to the guest OS 210 for installation 232 . The guest OS 210 may then be required to submit periodic heartbeat messages 236 during an active session with the hypervisor 212 . The hypervisor 212 will receive the heartbeat messages and apply predetermined frequency criteria 238 to ensure the messages are received in the correct time frame.
[0029] During a virtual environment setup/configuration, the guest OS 110 A/ 210 communicates with the hypervisor 120 / 212 , and the guest OS 110 A boots a guest kernel module (GKM), which is installed by the HMC 122 . Following the installation, the GKM 118 A receives a randomly generated secret shared key for communication with the HMC 122 . The GKM 118 A stores the key in its private memory and obfuscates the location to reduce the likelihood of unwarranted access. The HMC 122 and GKM 118 A communicate using a hypervisor 120 provided communication mechanism, such as a XEN event channel. All messages over the channel are encrypted with an authenticated encryption protocol using the shared key provided at boot-up of the guest OS 110 . The encryption protocol provides confidentiality, integrity, authenticity and replay protection. The GKM 118 A uses the encrypted channel to transmit (security) events to the HMC 122 . Also, the GKM 118 A periodically transmits a heartbeat message over the encrypted channel.
[0030] FIG. 2B illustrates a system communication diagram of a data communication between an administrator and a hypervisor management component and guest kernel module according to an example embodiment of the present application. Referring to FIG. 2B , in this communication configuration the administrator 260 receives alerts when the communication between the HMC 270 and the GKM 280 falters or more specifically fails to maintain a periodic heartbeat communication. In operation, the HMC 270 will initialize the communication with the GKM 280 with a key 252 . The key can be used to encrypt various communication messages shared between the GKM 280 and the HMC 270 . Thereafter, the heartbeat messages 254 may begin and continue per the agreed heartbeat protocol standard of sending and receiving of regular heartbeat messages. A security alert may be created and transmitted by the HMC 270 at any time to indicate whether there are any security threats present based on various security management criteria, such as unexpected actions, prolonged periods of time when no heartbeat messages are received, etc. In one example, a security alert 256 may be forwarded and/or created by the HMC 270 , which forwards the security alert 258 to the administrator 260 for any reason related to a potential security threat. The GKM 280 may begin transmitting heartbeat messages 262 , 264 , in succession at a predetermined frequency interval (i.e., every 30 seconds, 1 minute, 5 minutes, etc.). The absence of heartbeat messages after a predetermined period of time 266 may be detected by the HMC 270 . When the HMC 270 identifies that the GKM 280 stopped sending heartbeats the HMC 270 may response by either attempting to revive the GKM 280 via an OS specific command and/or alerting the administrator device 260 of a possible attack on the guest. In this example, the HMC 270 may attempt to reinstall the GKM 268 . The security alert 272 indicating the absence of heartbeats may then be sent to the administrator 260 to relay the absence of the heartbeats and the potential security threat.
[0031] A heartbeat(s) may be identified as a set of messages between two or more network elements that are repeatedly sent in order to guarantee that the connection is open and confirmed and that the sending party is still functioning. Any “cryptographic” message is signed using a pre-shared key by the sending party, and this may reduce 3 rd parties from forging the messages. The signed content includes a timestamp to prevent replay attacks. The shared key between the guest OS 210 and the hypervisor 212 may be based on any known form of encryption. The security events may be any type of event the GKM 280 considers as bearing some security related significance. For example, launching new processes, opening new connections, editing certain files, etc., may all be considered elevated security risks which require an audit of active security. The guest OS 210 will send heartbeat messages throughout the time of boot-up until shutdown. This ensures that the GKM code is running.
[0032] The operations of the instant application may be performed by checking an encrypted element in a host virtual environment by a native operating system (hypervisor) by installing a protected guest operating system component extension during booting of a virtual environment by the native operating system (OS) hypervisor. The protected extension issues a signed heartbeat message periodically via a secure protocol. The hypervisor may monitor the signed heartbeat message by a native OS according to a frequency criteria (e.g., after a certain number of seconds, minutes, hours, etc.), and responsive to detecting an absence of the signed heartbeat message within the frequency criteria, a first action may be performed by the native OS to facilitate avoidance of nefarious activity such as tampering in the virtual environment. Results and actions may include providing a notification, terminating the virtual environment, and rebooting the guest operating system with a replaced protected extension. Also, an application monitoring process in the virtual environment may be provided for validating integrity of the protected extension and integrity of the virtual environment, and responsive to detecting a corruption of the protected extension, a second action may be performed to reduce effects of the corruption. The virtual environment could be a virtual machine (VM), a logical partition (LPAR), and/or a work load partition (WPAR).
[0033] FIG. 3 illustrates a logic diagram 300 of at least one operation included in a guest OS setup and compliance function in a virtual environment. Referring to FIG. 3 , an initial virtual environment setup operation 312 invokes a hypervisor notification operation 314 to request a session via a communication channel. The hypervisor may then forward the agent 316 a plug-in agent which is installed/setup 318 so heartbeat messages may begin updating the hypervisor of the guest OS status. The heartbeat is received 322 and the hypervisor is notified. Also, the hypervisor is notified in the event of the heartbeat message not being received. In this case, the frequency criteria 324 will be identified to ensure the heartbeat was supposed to be received. As a result, in one embodiment, the session is terminated 326 to protect the virtual environment form a non-compliant guest OS.
[0034] FIG. 4 illustrates a hypervisor system 400 configured to perform one or more of the steps described or depicted herein. Referring to FIG. 4 , the hypervisor system 400 may be a single computer (such as a server), other device (that includes a processor and memory) or multiple computers or devices which support the operation of the security measures of the virtual environment. The system 400 includes a session initiation module 410 which receives a guest OS invite or request to enter a virtual session. A session processing module 420 may receive the request and prepare a response that includes an agent module being sent to the guest OS for installation. The session processing module may also process heartbeat messages received to validate the responses accordingly. A status update module 430 may ensure the heartbeat criteria is maintained accordingly and may store and update records of the guest OS and the session in a databank 440 .
[0035] One example method of operation performed by the hypervisor system 400 may include identifying a session initiation request at the session initiation module 410 from a guest kernel module at a hypervisor component of a server and initializing a session between the guest kernel module and the hypervisor component via the session processing module 420 . The method may also provide receiving periodic messages from the guest kernel module, and maintaining the session between the hypervisor component and the guest kernel module responsive to receiving the periodic messages from the guest operating system via the status update module 430 . The update module 430 may also perform transmitting an agent application to the guest operating system responsive to receiving the session initiation request. All information pertaining to the session may be stored in the databank 440 .
[0036] In one example, the hypervisor component of the server is the hypervisor management component (HMC). The system 400 may further provide determining a prolonged period of no periodic messages received, and notifying an administrator device of a potential security alert. As a result, the guest kernel module may be reinstalled responsive to determining the prolonged period of no periodic messages received. The periodic messages received from the guest kernel module are heartbeat messages which are periodically transmitted from the guest kernel module to the hypervisor component according to a predetermined time interval. The interval may be based on frequency criteria applied to the heartbeat message as specified by the HKM.
[0037] The steps described or depicted in connection with the embodiments disclosed herein may be embodied directly in hardware, firmware, in a computer program executed by a processor, or in one or more of the above. A computer program may be embodied on a non-transitory computer readable medium, such as a storage medium. For example, a computer program may reside in random access memory (“RAM”), flash memory, read-only memory (“ROM”), erasable programmable read-only memory (“EPROM”), electrically erasable programmable read-only memory (“EEPROM”), registers, hard disk, a removable disk, a compact disk read-only memory (“CD-ROM”), or any other form of storage medium known in the art.
[0038] Such a storage medium may be coupled to the processor such that the processor may read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an application specific integrated circuit (“ASIC”). In the alternative, the processor and the storage medium may reside as discrete components. For example, FIG. 5 illustrates an example network element 500 , which may represent any of the above-described network components, etc.
[0039] As illustrated in FIG. 5 , a memory 510 and a processor 520 may be discrete components of the network entity 500 that are used to execute an application or set of operations or steps as described or depicted herein. The application may be coded in software in a computer language understood by the processor 520 , and stored in a computer readable medium, such as, the memory 510 . The computer readable medium may be a non-transitory computer readable medium that includes tangible hardware components in addition to software stored in memory. Furthermore, a software module 530 may be another discrete entity that is part of the network entity 500 , and which contains software instructions that may be executed by the processor 520 . In addition to the above noted components of the network entity 500 , the network entity 500 may also have a transmitter and receiver pair configured to receive and transmit communication signals (not shown).
[0040] Although an exemplary embodiment of the system, method, and computer readable medium of the present application has been illustrated in the accompanied drawings and described in the foregoing detailed description, it will be understood that the application is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications, and substitutions without departing from the spirit or scope of the application as set forth and defined by the following claims. For example, the capabilities of the system of the various figures can be performed by one or more of the modules or components described herein or in a distributed architecture and may include a transmitter, a receiver or both. For example, all or part of the functionality performed by the individual components or modules, may be performed by one or more of these modules. Further, the functionality described herein may be performed at various times and in relation to various events, internal or external to the modules or components. Also, the information sent between various modules can be sent between the modules via at least one of: a data network, the Internet, a voice network, an Internet Protocol network, a wireless device, a wired device and/or via plurality of protocols. Also, the messages sent or received by any of the modules may be sent or received directly and/or via one or more of the other modules.
[0041] FIG. 6 illustrates another example configuration diagram of a virtual environment for multiple heartbeat requirements being assigned according to another example embodiment of the present application. Referring to FIG. 6 , the configuration 600 includes agents 612 A, 612 B, 612 C and 612 D which may be managed by the hypervisor 640 via the hypervisor management component (HMC) 642 to setup the guest kernel modules (GKMs) 620 A, 620 B, 620 C, 620 D, 620 E and 620 F to provide different heartbeat criteria messaging to the hypervisor 640 according to customized heartbeat criteria (HBC). Also, each guest OS 610 A, 610 B, 610 C and 610 D may have its own assigned respective agent. Additionally, the first GKM 620 A may have a heartbeat requirement of every 20 seconds 630 A, the next GKM 620 B may be instructed to provide heartbeats every 25 seconds 630 B, while the GKM 620 C is required to provide heartbeats every 23 seconds 630 C, and the GKM 620 D is required to provide heartbeats every 27 seconds 630 D and the GKM 620 E is required to provide heartbeats every 29 seconds 630 E and lastly the GKM 620 F is required to provide heartbeats every 22 seconds. The criteria is unique for each GKM and may be randomly assigned by the HMC 642 . The HBC is stored in a profile for each GKM so large groups of assignments can be organized and maintained for a growing capacity of GKMs in a virtual environment.
[0042] FIG. 7 illustrates a system communication diagram of a data communication between a plurality of guest operating systems and a hypervisor according to another example embodiment of the present application. Referring to FIG. 7 , the example 700 includes the administrator 760 receiving any security alerts 758 / 777 from the HMC 770 of the hypervisor. The GKMs 780 represent a pool of GKMs being managed simultaneously. In operation, the HMC 770 may initialize a first GKM 620 A with a particular key and set a first HBC requirement 752 . Similarly, the second 620 B and third 620 C GKMs may be required to begin following a HBC requirement 756 and 758 customized for their security and the security of the virtual environment. A security alert 754 may be sent at any time to alert the administrator of the new GKM requirements and any potential threats identified. The heartbeat messages 762 and 768 may follow and the HBC may be checked in a profile for each GKM stored in the HMC 770 for compliance with the customized intervals to receive the heartbeat messages. When there is no heartbeat received for a prolonged period of time 766 , for example, in this case, the third GKM 620 C has failed to maintain its heartbeat period requirement, then the HMC 770 may attempt to create an alert and notify the administrator 760 via a security alert 772 and/or reinstall the GKM 774 .
[0043] FIG. 8 illustrates a microvisor configuration for providing security to a virtual environment. Referring to FIG. 8 , the microvisor 810 operates outside of the guest OS 115 A and 115 B. The microvisor 810 is setup to provide virtual instances to users in a virtual environment on a task-by-task basis 812 A, 812 B, 812 C and 812 D. In the virtual configuration, the tasks may be any application, such as a MICROSOFT OFFICE application, a .pdf document application, a web browser, an email application, etc. The task(s) is initiated and requires customized resources 814 A and/or 814 B from an operating system or kernel 115 A/ 115 B. Resources may include a network port/session to communicate with other entities, memory, CPU allocation, or any other resource associated with a virtual environment operating in the cloud.
[0044] Each task managed by the microvisor may be configured as a single micro virtual machine or micro-VM. The various micro-VMs may correspond to a single task and may provide a secure environment where a user may interact with the task in an isolated micro-VM workspace that communicates with a remote virtual operating system. A task includes all processing both within the application and within a kernel of the operating system that is required to offer resources necessary for the task to operate. For example, initiating a web browser or MICROSOFT OFFICE application tab or a PDF document can be considered an individual task.
[0045] This task separation and isolation format of the microvisor or micro-VMs provides protection from any attempted change or unauthorized access of information made by an outside party. For example, a micro-VM has limited access to protected information and the network in general which is likely not accessible at all beyond the use pattern of the application operating in the micro-VM. Also, a micro-VM may identify and log all information accessed and attempted to be accessed by the user to provide a details of a potential attacker including network traffic, file access attempts and changes that were attempted to be made by malware on the operating system or file system.
[0046] FIG. 9 illustrates a system diagram that includes an operational scenario of the microvisor 980 being managed by the operating system/kernel for security purposes. Referring to FIG. 9 , the administrator 760 may be a point of contact for any security alerts 972 . However, the operating system 970 may manage the microvisor tasks by providing resources needed to perform the discrete tasks in exchange for a heartbeat protocol compliance measure. The task may be started and a micro-VM may initiate for the duration of the task use. For example, the microvisor 980 may initialize a first task 952 , such as an application for word processing or a web browser. As a result, the operating system 970 may identify certain resources necessary for the first task to operate in the microvisor environment and allocate those resources 954 and require a first heartbeat criteria (i.e., frequency of heartbeats, etc.) 956 to be maintained by the task or else the resources will be vacated and the task will fail to operate.
[0047] In a further example of FIG. 9 , a second task 958 may be spawned by the microvisor responsive to user criteria which requires additional resource allocation 962 for the second task and which will, in turn, require compliance with another heartbeat message criteria 964 as required by the operating system 970 . In the event that there is no heartbeat received for a certain period of time (i.e., time allocated by the heartbeat criteria for task 1 , task 2 , etc.), then the process 966 will require an alert be created and sent to the administrator 760 . Also, a task restart 974 may be performed to attempt to bring the task back to a compliance measure of the guest operating system. The lack of a heartbeat message after a predetermined period of time may equate to an application crash within the micro-VM instance. The remedies may include killing the micro-VM instance, restarting the application and reinstalling the micro-VM instance to initiate continued compliance with the micro-VM.
[0048] One skilled in the art will appreciate that a “system” could be embodied as a personal computer, a server, a console, a personal digital assistant (PDA), a cell phone, a tablet computing device, a smartphone or any other suitable computing device, or combination of devices. Presenting the above-described functions as being performed by a “system” is not intended to limit the scope of the present application in any way, but is intended to provide one example of many embodiments of the present application. Indeed, methods, systems and apparatuses disclosed herein may be implemented in localized and distributed forms consistent with computing technology.
[0049] It should be noted that some of the system features described in this specification have been presented as modules, in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom very large scale integration (VLSI) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices, graphics processing units, or the like.
[0050] A module may also be at least partially implemented in software for execution by various types of processors. An identified unit of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions that may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module. Further, modules may be stored on a computer-readable medium, which may be, for instance, a hard disk drive, flash device, random access memory (RAM), tape, or any other such medium used to store data.
[0051] Indeed, a module of executable code could be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network.
[0052] It will be readily understood that the components of the application, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the detailed description of the embodiments is not intended to limit the scope of the application as claimed, but is merely representative of selected embodiments of the application.
[0053] One having ordinary skill in the art will readily understand that the application as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations that are different than those which are disclosed. Therefore, although the application has been described based upon these preferred embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the application. In order to determine the metes and bounds of the application, therefore, reference should be made to the appended claims.
[0054] While preferred embodiments of the present application have been described, it is to be understood that the embodiments described are illustrative only and the scope of the application is to be defined solely by the appended claims when considered with a full range of equivalents and modifications (e.g., protocols, hardware devices, software platforms etc.) thereto. | Hypervisors and guest operating systems/virtual machines communicate in virtual environments to enable applications and other services. Security measures are a concern in implementing a secure environment. One feature may include at least one of identifying a session initiation request from a guest operation system at a hypervisor component of a server and receiving periodic messages from the guest operating system, and establishing and maintaining a session and connection between the hypervisor and the guest operating system responsive to receiving the periodic messages from the guest operating system. | 6 |
FIELD OF THE INVENTION
[0001] The invention relates generally to plasma etching of materials in the fabrication of integrated circuits. In particular, the invention relates to ashing of photoresist.
BACKGROUND ART
[0002] Plasma etching is widely used in the fabrication of silicon integrated circuits. One of its uses, often called dielectric etching, is used to form holes through dielectric layers to provide vertical electrical connections between different levels of the integrated circuit. A prototypical via structure is schematically illustrated in the cross-sectional view of FIG. 1 . A lower dielectric layer 10 formed on the surface of a wafer has a conductive feature 12 formed in its surface. An upper dielectric layer 14 is deposited over the lower dielectric layer 10 and its conductive feature 12 . A planar photoresist layer 16 is spun onto the so far unpatterned upper dielectric layer 14 and a stepper photographically exposes it according to a pattern of radiation to form a mask aperture 18 through the photoresist layer 16 to thereby form a photomask with the mask aperture 16 overlying the conductive feature 12 to be electrically contacted through a via. There may be additional layers formed between the upper dielectric layer 14 and the photoresist layer 16 such as an etching hard mask or an anti-reflection coating. The photomasked wafer is placed into a plasma etch reactor, which etches through the upper dielectric layer 14 down to the conductive feature to form a via hole 20 . Typically, the same etch reactor also etches through the anti-reflection coating and hard mask, if any, with the etching chemistry being changed between the layers. The dielectric etching is typically based on a fluorocarbon chemistry, for example, using hexafluorobutadiene (C 4 F 6 ).
[0003] After the dielectric etching, the via hole 20 is filled with a metal such as aluminum or copper to provide a vertical electrical connection to the conductive feature 12 . For a dual-damascene structure typically used with copper metallization, the via hole 20 is replaced by a shorter via hole at the bottom of the upper dielectric layer 14 connected to a horizontally extending trench at the top, both of which are simultaneously filled with copper. For a contact-layer metallization, the lower dielectric layer 10 is replaced by an active silicon layer and the conductive feature 12 is also composed of silicon although there may be complex silicides and gate oxides at the interface with the via hole 20 , which in this case is properly called a contact hole.
[0004] At the completion of dielectric etching, some of the photoresist may remain on top of the dielectric layer 14 or etching residues, often of a carbonaceous composition, may remain in the via hole 18 . The residues may form a polymeric coating 22 on the sides of the via hole 20 , which assists in producing a vertical etching profile, or form isolated etch residues 24 including some at the bottom of the via hole 20 . Similar polymeric coatings may cover the remainder of the photoresist to produce a hardened outer surface. The metal filling process requires that the via hole 20 be coated with a conformal liner including barrier layers and, in the case of copper metallization performed by electrochemical plating (ECP), a copper layer acting a seed layer and electroplating electrode. Currently, the barrier layer is typically a bilayer of TaN/Ta and it and the copper seed layer may be deposited by advanced forms of sputtering. It is important that the photoresist and other residues be removed from the structure prior to deposition of the layers lining the via hole since they degrade adhesion to the via sidewalls and increase contact resistance at the via bottom and in both cases affect device yield and reliability.
[0005] Plasma ashing has long been practiced to remove photoresist and other residues after etching. An oxygen plasma is very effective at etching away carbon-based layers. Although ashing was previously performed in a barrel asher designed for batch processing a large number of wafers, more current technology uses single-wafer plasma ashers, either as separate etch reactors or in a separate processing step performed in the same plasma etch reactor used for dielectric etching.
[0006] Conventional ashing is effective when the dielectric layer are formed of silicon dioxide (silica) having an approximate chemical composition of SiO 2 having a dielectric constant of around 3.9. Ashing has however presented difficulties when applied to more advanced low-k dielectrics needed for advanced integrated circuits. Early low-k dielectrics were formed by doping silica with fluorine to reduce the dielectric constant to about 3.5. Even lower dielectric constants in the low-3 range can be obtained by a hydrogenated silicon oxycarbide material, such as Black Diamond dielectric available from Applied Materials of Santa Clara, Calif. Still lower dielectric constants of less than 3 have been obtained by depositing such materials to be porous. Oxygen ashing of these materials causes many problems. The oxygen plasma not only attacks the carbonaceous photoresist remnants and other residue, it also tend to deplete the carbon content of the silicon oxycarbide and increases its dielectric constant. Porous dielectric materials are relatively fragile and even more prone to damage from the oxygen plasma due to partial penetration of oxygen into the pores and the collapse of the pores.
[0007] Accordingly, advanced ashing has shifted from the oxidizing chemistry of an oxygen plasma to a reducing chemistry of a plasma formed of some combination of hydrogen and possibly nitrogen, for example, H 2 , H 2 /N 2 , or NH 3 . Ashing based on hydrogen radicals H* exhibits higher performance and less dielectric damage than oxygen ashing. However, hydrogen ashing is a very slow process due to a low reducing reaction rate and the low hydrogen radical density generated in an environment of only reducing gases. While oxygen ashing may require 20 seconds of processing, hydrogen ashing may require ten times as long, clearly an economic disadvantage. Accordingly, often a small amount of oxygen may be added to the reducing gas to increase the ashing rate and ashing efficiency. However, porous low-k materials are sensitive even to small amounts of oxygen, which can remove significant carbon from the silicon oxycarbide material and collapse the pore structure and increase the dielectric constant.
SUMMARY OF THE INVENTION
[0008] An oxygen-free plasma ashing process is performed in which the main ashing is includes a plasma formed from hydrogen gas, optional nitrogen gas, water vapor, and an otherwise inactive or diluent gas such as argon or helium. Ammonia may replace the hydrogen and nitrogen. The plasma is formed from more water vapor than hydrogen gas, and more inactive gas than water vapor.
[0009] The ashing is particularly useful for low-k dielectric materials containing carbon as well as silicon oxide, for example, hydrogenated silicon oxycarbide.
[0010] Optionally, a hydrocarbon gas, such as methane, may be added to the plasma of the main ashing step. The addition of hydrocarbon is particularly useful for porous low-k dielectric materials, for example, having a dielectric constant less than three.
[0011] An initial oxygen-free plasma ashing or surface treating step includes a plasma formed from a hydrogen-containing reducing gas, such as hydrogen or ammonia, and optional nitrogen gas but no water vapor. The surface treating step may be shorter than the main ashing step.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross-sectional view of a via hole after dielectric etching including residual photoresist, sidewall polymeric coating, and other etch residue to be removed by ashing.
[0013] FIG. 2 is a schematic cross-sectional view of a plasma asher usable with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] The addition of water vapor and a large amount of argon or helium to the hydrogen-based ashing plasma greatly increases the concentration of hydrogen radicals and increases the ashing rate with reduced damage to low-k dielectrics.
[0015] The invention may be practiced in a plasma ashing reactor 30 , schematically illustrated in the cross-sectional view of FIG. 2 . A vacuum processing chamber 32 is pumped by a vacuum pumping system 36 to the low Torr range. A pedestal 38 within the chamber 32 supports a wafer 40 to be ashed in opposition to a gas showerhead 42 supplying a process gas through a large number of apertures 44 .
[0016] The process gas is supplied to a manifold 46 in back of the showerhead 42 through a remote plasma source 48 which excites the process gas into a plasma. The remote plasma source 48 may be located a distance away from the vacuum chamber 48 but is still considered ancillary to it since the gas containing the plasma generated in the remote plasma source 48 flows into the vacuum chamber 48 in its active plasma state. Preferably, mostly radicals and relatively few plasma ions are delivered into the processing chamber 32 . Some of the details of the remote plasma source and the manifold are disclosed by Fu in U.S. patent application Ser. No. 11/351,676, filed Feb. 10, 2006. The remote plasma source 48 may utilize a microwave excitation source operating in the low gigahertz range, for example, 2.54 GHz, or an RF excitation source operating in the sub-gigahertz range, for example, 270 to 650 kHz. The remote plasma source 48 advantageously includes a charged particle filter so that the plasma delivered to the chamber contains only neutral radicals and no charged ions. If hydrogen gas (H 2 ) is used as the primary ashing gas, it is supplied to the remote plasma source 48 from a hydrogen gas source 50 through a mass flow controller 52 . Nitrogen gas (N 2 ) may be supplied from a nitrogen gas source 54 through another mass flow controller 56 . Nitrogen tends to act as a passivator for hydrogen radical etching.
[0017] Water vapor (H 2 O) is supplied to the remote plasma source 48 from a vacuum-sealed water ampoule 60 containing a pool 62 of liquid water. A mass flow controller 64 meters water vapor from the ampoule 60 . The vapor pressure of water at room temperature is about 20 Torr, which is well above the usual vacuum levels at which the remote plasma source 48 operates. Accordingly, once the ampoule 60 has been back pumped, a water vapor having a pressure of about 20 Torr exists in a head space 66 above the liquid water pool 62 in the ampoule 60 . The ampoule 60 may be mounted directly on the chamber 32 to minimize the length of tubing, on the walls of which water is likely to condense.
[0018] A controller 70 acting in accordance with a recipe inserted into the controller 70 in a recordable medium 72 such as a CDROM controls the pumping system 36 , the remote plasma source 48 , and the various mass flow controllers including the mass flow controllers 52 , 56 , 64 already described as well as others.
[0019] According to the invention, an otherwise inactive gas such as argon (Ar) is supplied from an argon gas source 80 metered by a mass flow controller 82 . Helium (He) may be substituted for the argon. The argon promotes dissociation of H 2 O to H* and OH* in what is believed to be a Penning process in which the energy of an excited argon radical is transferred to the water components. Thereby, a much higher density of hydrogen radicals H* is produced from the water vapor than is possible with H 2 alone. As a result, although argon and helium are usually considered to be inactive diluent gases, it is believed that they remain inactive in the actual ashing but promote the generation of a high density of active ashing radicals. Nonetheless, H 2 advantageously included in the recipe suppresses the generation of oxygen radicals O*. Further, N 2 is advantageously added to not only enhance the dissociation of H 2 O but also to provide some passivation during the ashing process.
[0020] One embodiment of the process of ashing hydrogenated silicon oxycarbide tabulated in TABLE 1 is a two-step process tabulated in TABLE 1 with process gas flows presented in units of standard cubic centimeters (sccm).
[0000] TABLE 1 Step 1 Step 2 H 2 (sccm) 600 600 N 2 (sccm) 100 H 2 O (sccm) 1000 Ar (sccm) 3000 Pressure (Torr) 1 1 RPS Power (W) 5000 5000 Time (s) 20 60
The first step is a moderately soft etch or surface treatment and does not harden the surface of the photoresist or the polymeric sidewall coating. The first step is based primarily on a hydrogen reducing chemistry and hence is slow. However, it is intended only to etch away the surface. The H 2 /N 2 may be replaced other reducing gases such as H 2 alone or ammonia (NH 3 ). The second step is intended to quickly remove the bulk part of the photoresist and residue. The second step is the main ashing step and is longer than the initial surface treating step.
[0021] It is understood the summarized recipe is only representative of the process of the invention. The pressure range is easily extended to 0.5 to 5 Torr; the RPS source power range, to 2 kW to 8 kW for a 300 mm chamber; the hydrogen flow to 200 to 2000 sccm, the argon flow to 3000 to 10,000 sccm; and the water vapor flow to 500 to 3000 sccm. As mentioned before, helium may be substituted for argon. In general terms, in the first step, predominantly hydrogen is supplied but a lesser amount of nitrogen may be supplied. In the second step, more argon than water and less hydrogen than water vapor are supplied. Oxygen gas or its radical form of ozone is not supplied in either step.
[0022] The main ashing process of the second step may be practiced without the preliminary surface treatment of the first step or with some other type of preliminary treatment.
[0023] The recipe of TABLE 1 is effective for non-porous low-k dielectrics of hydrogenated silicon oxycarbide. However, for the now favored porous low-k dielectrics of the same general composition, additional passivation is desired. Accordingly, a hydrocarbon, such as methane (CH 4 ), may be supplied from a hydrocarbon gas source 84 through another mass flow controller 86 , but other carbon- and hydrocarbons consisting of hydrogen and carbon may be substituted, such as ethane (C 2 H 6 ), ethylene (C 2 H 4 ), and acetylene (C 2 H 2 ) as well as higher alkanes, alkenes, alkynes, and the like. A recipe preferred for porous low-k dielectrics is tabulated in TABLE 2.
[0000] TABLE 2 Step 1 Step 2 H 2 (sccm) 600 600 N 2 (sccm) 100 H 2 O (sccm) 1000 Ar (sccm) 3000 CH 4 (sccm) 20 Pressure (Torr) 1 1 RPS Power (W) 5000 5000 Time (s) 20 60
The recipe of TABLE 2 closely follows that of TABLE 1 except for the addition in the second step of an amount of methane substantially less than the other components. The small amount of hydrocarbon is believed to passivate and protect the exposed porous low-k dielectric by sealing the pores of the dielectric material and prevent the etching plasma, particularly the oxygen component, from penetrating deep within the pores and degrading the dielectric material.
[0024] The invention is not limited a plasma asher using a remote plasma source but can be practiced in a plasma diode etch reactor in which the plasma is generated within the vacuum chamber adjacent the wafer or other substrate but the ionic content of the plasma needs to be minimized. Further, the invention is not limited to the described low-k dielectric of hydrogenated silicon oxycarbide but can be applied to other types of dielectric materials and indeed may be applied to ashing after a metal or silicon etching process.
[0025] The invention thus provides fast but protective ashing process particularly useful in ashing low-k dielectric materials. | An oxygen-free hydrogen plasma ashing process particularly useful for low-k dielectric materials based on hydrogenated silicon oxycarbide materials. The main ashing step includes exposing a previously etched dielectric layer to a plasma of hydrogen and optional nitrogen, a larger amount of water vapor, and a yet larger amount of argon or helium. Especially for porous low-k dielectrics, the main ashing plasma additionally contains a hydrocarbon gas such as methane. The main ashing may be preceded by a short surface treatment by a plasma of a hydrogen-containing reducing gas such as hydrogen and optional nitrogen. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of and priority to U.S. Provisional Patent Application No. 61/075,548, filed Jun. 25, 2008, the entire disclosure of which is incorporated by reference herein.
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates to a surgical access apparatus for positioning within an incision in tissue. More particularly, the present disclosure relates to a surgical access apparatus that is adapted to removably receive one or more surgical objects, and configured for insertion into, and anchoring within, the incision.
[0004] 2. Background of the Related Art
[0005] Today, many surgical procedures are performed through small incisions in the skin, as compared to the larger incisions typically required in traditional procedures, in an effort to reduce both trauma to the patient and recovery time. Generally, such procedures are referred to as “endoscopic”, unless performed on the patient's abdomen, in which case the procedure is referred to as “laparoscopic”. Throughout the present disclosure, the term “minimally invasive” should be understood to encompass both endoscopic and laparoscopic procedures.
[0006] In general, during a minimally invasive procedure, a surgical access apparatus or portal member is used to facilitate access to the surgical site with surgical instrumentation, e.g., endoscopes, obturators, staplers, and the like. A typical surgical access apparatus defines a passageway or lumen through which the surgical instrumentation is inserted and the procedure is carried out.
[0007] While many varieties of surgical access apparatus are known in the art, a continuing need exists for a surgical access apparatus that may be releasably and reliably secured within the patient's tissue throughout the duration of the minimally invasive procedure.
SUMMARY
[0008] The present disclosure relates to a surgical apparatus for positioning within an incision in tissue. In one aspect of the present disclosure, the surgical access apparatus includes an elongated seal member defining a longitudinal axis and a deployment member.
[0009] The elongated seal member is adapted to transition between first and second conditions. In the first condition, the elongated seal member defines a first transverse dimension sufficient to facilitate securement of the elongated seal member within the incision and a tissue engaging portion configured to engage the tissue in substantially sealed relation. In the second condition, the elongated seal member defines a second transverse dimension, which is less than the first transverse dimension, to facilitate insertion of the elongated seal member within the incision.
[0010] The elongated seal member is at least partially composed of an at least semi-resilient material such that the elongated seal member is biased towards the first condition thereof. The elongated seal member includes a longitudinal passageway for the reception and passage of a surgical object in substantially sealed relation.
[0011] The elongated seal member includes a proximal end, which may include a stiffening member, and a distal end, which may include a lip. The stiffening member is adapted to facilitate anchoring of the elongated seal member within the incision, and in one embodiment thereof, may be generally annular in shape. The lip extends outwardly relative to the longitudinal axis, when the elongated seal member is in the first condition, and is dimensioned to engage the tissue to resist removal of the elongated seal member therefrom.
[0012] In one embodiment, the elongated seal member defines an internal cavity that is configured to retain a fluid therein, and in another embodiment, the elongated seal member defines a variable cross-sectional dimension along the longitudinal axis.
[0013] The deployment member of the surgical access apparatus is at least partially positionable within the longitudinal passageway of the elongated seal member. The deployment member is secured to the elongated seal member along an internal surface thereof such that distal longitudinal movement of the deployment member along the longitudinal axis causes the elongated seal member to transition from the first condition to the second condition. When subjected to a predetermined force, the deployment member may be detached from the elongated seal member to permit the deployment member to be removed from the longitudinal passageway with the elongated seal member in the first condition, thereby leaving the elongated seal member within the incision to receive the surgical object. The deployment member may be releasably secured to the elongated seal member with an adhesive.
[0014] In one embodiment, the deployment member includes a sleeve having an opening to receive at least one digit of a user to thereby facilitate grasping and removal of the deployment member from the elongated seal member.
[0015] In another aspect of the present disclosure, the surgical access apparatus includes a housing configured to removably receive at least one surgical object, an elongated member extending distally from the housing, and at least one filament secured to the elongated member and extending proximally relative thereto.
[0016] The housing includes locking structure configured to engage the at least one filament and thereby maintain the second condition of the elongated member. The locking structure includes at least one channel formed in the housing that is configured to at least partially receive the at least one filament. In one embodiment, the locking structure may include a locking member that is repositionable between unlocked and locked positions. In this embodiment, the locking member defines a channel therethrough that is configured to at least partially receive the at least one filament. In the unlocked position, the channel of the locking member and the channel formed in the housing are substantially aligned, and in the locked position, the channel of the locking member and the channel formed in the housing are substantially misaligned. The locking member may be biased towards the locked position by a biasing member.
[0017] The elongated member includes a tubular braid defining an axial lumen that is configured to allow the at least one surgical object to pass therethrough. The braid is formed of a mesh of fibers which may be either substantially elastic, or substantially inelastic.
[0018] The elongated member is adapted to transition from a first condition, in which the elongated member is configured for at least partial insertion within the incision, and a second condition, in which the elongated member defines a tissue engaging portion configured to facilitate anchoring of the elongated member within the patient's tissue.
[0019] The filament, or filaments, are dimensioned for grasping by a user such that drawing the at least one filament proximally transitions the elongated member from the first condition to the second condition. The filament, or filaments, may be disposed within the lumen of the elongated member, or externally thereof. The filament, or filaments, may alternatively be secured to an intermediate or distal portion of the elongated member.
[0020] In one embodiment, the surgical access apparatus further includes a membrane disposed about at least a proximal portion of the elongated member to facilitate anchoring of the elongated member within the tissue. The membrane may also facilitate passage of the at least one surgical object through the elongated member.
[0021] In another aspect of the present disclosure, a method of percutaneously accessing an underlying surgical work site is disclosed. The first step of the method includes providing a surgical access apparatus having an elongated seal member and a deployment member.
[0022] The elongated seal member defines a longitudinal axis, a proximal end, and a distal end. The elongated seal member has a longitudinal passageway for reception and passage of a surgical object and is adapted to transition between a first condition and a second condition. In the first condition, the elongated seal member defines a first transverse dimension, and in the second condition, the elongated seal member defines a second transverse dimension. The elongated seal member comprises an at least a semi-resilient material to be normally biased towards the first condition thereof.
[0023] The deployment member is at least partially positionable within the longitudinal passageway of the elongated seal member and is secured to the elongated seal member along an internal surface adjacent the distal end thereof. Upon distal longitudinal movement of the deployment member along the longitudinal axis, the elongated seal member is caused to transition from the first condition to the second condition.
[0024] The deployment member is advanced distally within the longitudinal passageway of the elongated seal member to thereby transition the elongated seal member into the second condition, and secure the elongated seal member within the incision. Subsequently, the surgical access apparatus is inserted into the incision, the deployment member is removed from the elongated seal member, and the surgical object is inserted into the longitudinal passageway and used to perform at least one surgical function. Thereafter, the surgical object is removed from the longitudinal passageway, the elongated seal member is removed from the incision, and the incision is closed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein:
[0026] FIG. 1 is a perspective view of a surgical access apparatus including a seal member and a sleeve member in accordance with one aspect of the present disclosure.
[0027] FIG. 2A is a side cross-sectional view of the seal member of FIG. 1 shown in a first condition with the sleeve member removed therefrom.
[0028] FIG. 2B is a side cross-sectional view of the seal member of FIG. 1 shown in a first condition with the sleeve member inserted therein and secured thereto.
[0029] FIG. 3 is a side cross-sectional view of the seal member of FIG. 1 inserted into an incision in tissue and shown in a first condition with a surgical object extending therethrough.
[0030] FIG. 4 is a side cross-sectional view of the seal member of FIG. 1 shown in a second condition with the sleeve member inserted therein and secured thereto.
[0031] FIG. 5 is a side cross-sectional view of one embodiment of the seal member of FIG. 1 incorporating a fluid disposed within an internal cavity.
[0032] FIG. 6 is a side cross-sectional view of a surgical access apparatus including a housing, an elongate member, shown in a first condition, and filaments in accordance with another aspect of the present disclosure.
[0033] FIG. 7 is a side cross-sectional view of the surgical access apparatus of FIG. 6 with the elongate member shown in a second condition and inserted into an incision in a patient's tissue.
[0034] FIG. 8 is a side cross-sectional view of one embodiment of the surgical access apparatus of FIG. 6 with the filaments disposed externally of the elongate member.
[0035] FIG. 9A is a side cross-sectional view of one embodiment of locking structure for use with the surgical access apparatus of FIG. 6 shown in a locked condition.
[0036] FIG. 9B is a side cross-sectional view of the locking structure of FIG. 9A shown in an open condition.
[0037] FIGS. 10A-10B are side cross-sectional views of another embodiment of the surgical access apparatus of FIG. 6 including a membrane disposed about the elongate member, the elongate member being respectively shown in its first and second conditions.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0038] In the drawings and in the description which follows, in which like references numerals identify similar or identical elements, the term “proximal” will refer to the end of the apparatus which is closest to the user during use, while the term “distal” will refer to the end which is furthest from the user. Additionally, the term “incision” should be understood as referring to any opening in a patient's tissue, whether formed by the user or pre-existing.
[0039] With reference to FIGS. 1A-3 , a surgical access apparatus 10 is disclosed that is removably positionable within a percutaneous incision 12 formed in a patient's tissue “T” during the course of a surgical procedure, e.g., a minimally invasive procedure, to facilitate access to a patient's underlying cavities, tissues, organs, and the like with one or more surgical objects “I” ( FIG. 3 ). In one aspect of the present disclosure, surgical access apparatus 10 includes a deployment member 100 that is releasably secured to an elongated seal member 200 .
[0040] Deployment member 100 is secured to an internal surface 210 of elongated seal member 200 such that at least a portion of deployment member 100 extends proximally of elongated seal member 200 . Deployment member 100 may be secured to internal surface 210 through any means suitable for the intended purpose of allowing deployment member 100 to be detached from elongated seal member 200 at the election of the user, including but not being limited to the use of a biocompatible adhesive. In one embodiment, as seen in FIGS. 1A-3 , deployment member 100 is configured as a sleeve defining an opening 102 that extends at least partially therethrough. Opening 102 is configured to facilitate grasping of deployment member 100 by a user, e.g., by placing one or more digits therein.
[0041] Elongated seal member 200 includes a proximal portion 202 , an intermediate portion 204 , a distal portion 206 , and a passageway 208 defined by internal surface 210 and extending longitudinally through elongated seal member 200 along a longitudinal axis “A”.
[0042] Proximal portion 202 includes a proximal surface 212 extending outwardly with respect to the longitudinal axis “A” along a transverse axis “B”, and defines a first dimension D 1 . In one embodiment, as seen in FIGS. 1-3 , proximal surface 212 may include at least one stiffening member 214 . Stiffening member 214 may extend distally from proximal portion 202 and at least partially into intermediate portion 204 , as depicted. Alternatively, stiffening member 214 may be substantially annular in configuration and disposed solely within proximal portion 202 . Stiffening member 214 may be formed of any biocompatible material suitable for the intended purpose of rigidifying elongated seal member 200 to facilitate the anchoring thereof within tissue, as discussed below.
[0043] Intermediate portion 204 extends distally from proximal portion 202 . Intermediate portion 204 and defines a second dimension D 2 along transverse axis “B” and a length “L”. The second dimension D 2 of intermediate portion 204 may be either substantially constant along its length “L”, or variable.
[0044] Distal portion 206 includes a lip 216 extending in transverse relation to the longitudinal axis “A”, along axis “B”, and defines a third dimension D 3 . Lip 216 is configured to engage tissue “T” ( FIG. 3 ) when elongated seal member 200 is disposed within percutaneous incision 12 , and thereby resist the removal of elongated seal member 200 .
[0045] The respective first and third dimensions D 1 , D 3 of proximal and distal portions 202 , 206 are each greater than the second dimension D 2 of intermediate portion 204 such that elongated seal member 200 defines an “hour-glass” shape or configuration to assist in anchoring elongated seal member 200 within tissue “T” ( FIG. 3 ). However, an embodiment in which the second dimension D 2 of intermediate portion 204 is substantially equivalent to the respective dimensions D 1 , D 3 of proximal and distal portions 202 , 206 is also within the scope of the present disclosure. Additionally, the third dimension D 3 of distal portion 206 may be appreciably smaller than the first dimension D 1 of proximal portion 202 , as shown in FIGS. 1-3 , or alternatively, the respective first and third dimensions D 1 , D 3 of proximal and distal portions 202 , 206 may be substantially equal.
[0046] The outermost surfaces of proximal and distal portions 202 , 206 are substantially planar in configuration. However, an embodiment is also contemplated herein in which either or both of proximal and distal surfaces 202 , 206 , respectively, define surfaces that are substantially arcuate to facilitate the insertion of elongated seal member 200 within incision 12 .
[0047] Passageway 208 is configured to removably receive surgical object “I” ( FIG. 3 ), as discussed in further detail below. Passageway 208 defines an inner dimension “D P ” that is smaller than the outer dimension “D I ” of surgical object “I” such that the introduction of surgical object “I” to elongated seal member 200 causes passageway 208 to expand or enlarge outwardly with respect to the longitudinal axis “A” along transverse axis “B”. Although the outer dimension “D I ” of surgical object “I” will generally lay within the range of about 3 mm to about 15 mm, the employ of surgical objects have substantially larger or smaller outer dimensions is also within the scope of the present disclosure.
[0048] Referring now to FIG. 4 as well, elongated seal member 200 is adapted to transition from a first (or normal) condition ( FIGS. 1-3 ) to a second (or extended) condition ( FIG. 4 ). In the first condition, seal member 200 defines an overall length “L 1 ”, and the dimension D 2 of intermediate portion 204 is greater than that of the incision 12 to thereby facilitate the anchoring of elongated seal member 200 , as discussed in further detail below. To further assist in the anchoring of elongated seal member 200 , intermediate portion 204 exhibits a substantially irregular profile in the first condition in which a plurality of tissue engaging surfaces 218 are defined. The contact between tissue engaging surfaces 218 and tissue “T” may also form a substantially fluid-tight seal therebetween. When in the first condition, lip 216 extends outwardly along transverse axis “B” to further facilitate the anchoring of elongated seal member 200 within tissue “T” and resist the removal of seal member 200 therefrom. In the second condition, elongated seal member 200 defines an overall length “L 2 ” that is greater than the length “L 1 ” of the elongated seal member 200 when in the first condition, and intermediate portion 204 exhibits a profile that is substantially more uniform, in that tissue engaging surfaces 218 are substantially less prominent. Additionally, when in the second condition, lip 216 extends generally in the distal direction so as not to inhibit the insertion of elongated seal member 200 within incision 12 .
[0049] To facilitate the transition of elongated seal member 200 from the first condition to the second condition, the user grasps deployment member 100 and applies a force “F” thereto that is directed distally, thereby advancing deployment member 100 in that direction. As deployment member 100 is advanced, the engagement between deployment member 100 and internal surface 210 causes intermediate portion 204 to elongate, and lip 216 to deflect, in the distal direction. It should be noted that the elongation of elongated seal member 200 during the transition thereof from the first condition to the second condition may cause portions of elongated seal member 200 , e.g., intermediate and distal portions 202 , 206 , respectively, to deform inwardly along transverse axis “B”, thereby reducing the dimensions of elongated seal member 200 , e.g., the respective dimensions D 2 , D 3 of intermediate and distal portions 202 , 206 , and further facilitating the insertion of elongated seal member 200 within incision 12 .
[0050] Elongated seal member 200 may be formed of any suitable biocompatible material that is at least semi-elastic and deformable in nature, e.g., silicon or memory foam. Forming elongated seal member 200 of an elastic material allows elongated seal member 200 to resiliently transition between the first and second conditions thereof, and acts to return elongated seal member 200 to its first condition upon the removal of force “F” from deployment member 100 . Forming elongated seal member 200 of a material that is also deformable in nature allows intermediate portion 204 to conform to both the smaller dimensions of incision 12 upon the insertion of elongated seal member 200 therein, and permits passageway 208 to accommodate the larger dimensions of surgical object “I”.
[0051] Referring to FIG. 5 , in one embodiment, the resiliency and deformability of elongated seal member 200 is achieved through the incorporation of one or more fluids 220 . Fluid 220 is retained within an internally defined cavity 222 . In this embodiment, fluid 220 may be any suitable biocompatible fluid, including but not being limited to air, water, or saline.
[0052] With respect now to FIGS. 1-4 , the use and function of elongated seal member 200 during the course of a typical minimally invasive procedure will be discussed. Initially, the peritoneal cavity (not shown) may be insufflated with a suitable biocompatible gas such as, e.g., CO 2 gas, such that the cavity wall is raised and lifted away from the internal organs and tissue housed therein, providing greater access thereto. The insufflation may be performed with an insufflation needle or similar device, as is conventional in the art. It should be noted that the present disclosure also contemplates the employ of surgical access apparatus 10 during the course of a procedure in which insufflation is not required or utilized.
[0053] Either prior or subsequent to insufflation, incision 12 is created in the patient's tissue “T”. The dimensions of incision 12 may be varied dependent upon the nature of the procedure. However, when surgical apparatus 10 is employed during the course of procedure performed in an insufflated workspace, for reasons explained just below, it is particularly desirable to incise the tissue “T” so as to create an incision 12 defining dimensions smaller than those defined by intermediate portion 204 when elongated seal member 200 is in its first condition.
[0054] Prior to its insertion, elongated seal member 200 is in its first condition. In the first condition, the dimensions of elongated seal member 200 , e.g., the respective dimensions D 2 , D 3 of the intermediate and distal portions 202 , 206 , may prohibit the insertion of elongated seal member 200 into incision 12 . To allow for the insertion of elongated seal member 200 , the user applies a force “F” to deployment member 100 , advancing deployment member 100 distally and transitioning elongated seal member 200 into its second condition. In the second condition, elongated seal member 200 is subject to a proximally directed biasing force “F B ” that is created by virtue of the resilient nature of the material comprising elongated seal member 200 . Biasing force “F B ” resists the influence of force “F” and is exerted upon deployment member 100 through the association between deployment member 100 and elongated seal member 200 . Upon transitioning into the second condition, elongated seal member 200 is inserted into incision 12 and force “F” is removed from deployment member 100 . Upon the removal of force “F”, biasing force “F B ” returns elongated seal member 200 to its first condition, thereby urging deployment member 100 proximally. After being restored to its first condition, tissue engaging surfaces 218 engage tissue “T” to thereby assist in securing elongated seal member 200 within the patient's tissue “T”. The user may then disengage deployment member 100 from internal surface 210 of passageway 208 by applying a predetermined force thereto, e.g., by pulling or drawing deployment member 100 proximally. Subsequently, the user may introduce one or more surgical objects “I” into passageway 208 such that the minimally invasive procedure may be carried out through apparatus 10 .
[0055] As indicated above, the deformable nature of the material comprising elongated seal member 200 allows intermediate portion 204 to conform to the smaller dimensions of incision 12 in addition to allowing passageway 208 to expand and accommodate the larger dimensions of surgical object “I”. Accordingly, elongated seal member 200 may create substantially fluid-tight seals with both tissue “T” and surgical object “I”, thereby substantially preventing the escape of insufflation gas, if any, and facilitating the secure anchoring of elongated seal member 200 within tissue “T” throughout the course of the procedure.
[0056] After completing the procedure and withdrawing surgical object “I”, elongated seal member 200 may be removed from incision 12 . It should be noted that the material comprising elongated seal member 200 allows for the deformation thereof during its withdrawal from incision 12 to thereby avoid any unnecessary trauma to the patient's tissue “T”. Thereafter, incision 12 may be closed.
[0057] Referring now to FIGS. 6-7 , in an alternate aspect of the present disclosure, surgical access apparatus 10 includes a housing 300 , an elongated member 400 extending distally from housing 300 , and one or more filaments 500 that are secured to the elongated member 400 .
[0058] Housing 300 defines a longitudinal axis “A” and may be fabricated from any suitable biocompatible material including moldable polymeric materials, stainless steel, titanium or the like. Housing 300 is configured for manual engagement by a user and includes an opening (not shown) extending therethrough that is configured for the reception and passage of a surgical object “I”. Housing 300 includes an outer wall 302 which defines a flange 304 having a distal surface 306 and may, optionally, include an internal seal or valve (not shown), such as a duck-bill or zero-closure valve, adapted to close in the absence of surgical object “I”. Examples of such an internal seal or valve may be seen in commonly assigned U.S. Pat. Nos. 5,820,600 to Carlson, et al. and 6,702,787 to Racenet et al., which issued Oct. 13, 1998 and Mar. 9, 2004, respectively, the entire contents of which are incorporated by reference herein. Housing 300 further includes locking structure 308 , which is discussed in further detail below.
[0059] Elongated member 400 defines an axial lumen 402 that extends therethrough, along longitudinal axis “A”. Lumen 402 is configured for the reception and passage of a surgical object “I”. Elongated member 400 is configured as a braid 404 formed of a mesh of biocompatible fibers 406 . In one embodiment of elongated member 400 , fibers 406 may be formed of a substantially elastic material such that elongated member 400 may expand along an axis “B” that is transverse, e.g., orthogonal, in relation to longitudinal axis “A”. However, in an alternate embodiment, fibers 406 may be formed of a substantially inelastic material, e.g., polyamide fiber, stainless steel, or the like, such that elongated member 400 experiences a measure of shortening along longitudinal axis “A” upon the introduction of surgical object “I”, further details of which may be obtained through reference to U.S. Pat. No. 5,431,676 to Dubrul et al., the entire contents of which are incorporated by reference herein. The braid 404 may be comprised of fibers 406 having any suitable configuration, including but not being limited to round, flat, ribbon-like, or square.
[0060] Filaments 500 have proximal ends 502 that extend proximally beyond housing 300 and distal ends 504 that are secured to elongated member 400 at attachment points 506 . Attachment points 506 may be located at any suitable position along elongated member 400 proximal of a distal-most end 408 thereof, e.g., at a proximal section 410 , an intermediate section 412 , or a distal section 414 . As seen in FIGS. 6-7 , in one embodiment, filaments 500 are disposed within lumen 402 of elongated member 400 , whereas in an alternate embodiment, filaments 500 are disposed externally of elongated member 400 , as seen in FIG. 8 . In yet another embodiment, filaments 500 may be interlaced within the mesh comprising the elongated member 400 . Filaments 500 may be secured to elongated member 400 at attachment points 506 through any suitable means, such as adhesives. Alternatively, filaments 500 may be integrally formed with elongated member 400 such that filaments 500 constitute proximal extensions of fibers 406 . Filaments 500 are used to facilitate the transition of elongated member 400 from a first (or initial) condition ( FIG. 6 ) to a second (or activated) condition ( FIG. 7 ).
[0061] In the first condition, elongated member 400 defines an initial length “L 1 ” and an initial outer dimension “D 1 ”. Length “L 1 ” may vary depending on the intended usage for apparatus 10 , but in general, “L 1 ” will lie substantially within the range of about 10 cm to about 25 cm, although elongate members 400 that are substantially longer or shorter are also contemplated herein. The initial outer dimension “D 1 ” of elongate member is smaller than the dimensions of incision 12 such that elongated member 400 may be inserted and advanced distally through incision 12 will little or no resistance.
[0062] Upon the application of a force “F” to filaments 500 in the direction of arrow “B”, e.g., by pulling or drawing filaments 500 proximally, elongated member 400 is shortened along the longitudinal axis “A”, thereby transitioning into the second condition. In the second condition, elongated member 400 defines a length “L 2 ” that is appreciably less than its initial length “L 1 ”. Additionally, in the second condition, elongated member 400 defines a tissue engaging portion 416 having an outer dimension “D 2 ” that is appreciably greater than the outer dimension “D 1 ” of the elongated member 400 in the first condition. Tissue engaging portion 416 contacts the patient's tissue “T” about incision 12 and, in conjunction with flange 304 of housing 300 , facilitates the anchoring of apparatus 10 . Additionally, tissue engaging portion 416 acts to at least partially form a seal with tissue “T”.
[0063] As previously indicated, housing 300 of apparatus 10 includes locking structure 308 . Locking structure 308 acts to maintain elongated member 400 in the second condition thereof. As seen in FIGS. 5-6 , in one embodiment, locking structure 308 includes one or more channels 310 formed in housing 300 and one or more engagement members 312 . Channels 310 extend at least partially through housing 300 and have an egress 314 formed either in a proximal-most surface 316 or outer wall 302 of housing 300 . In this embodiment, filaments 500 extend through channels 310 such that the proximal ends 502 thereof may be grasped by the user to thereby transition elongated member 400 into the shortened condition thereof. To maintain elongated member 400 in the second condition, the proximal ends 502 of filaments 500 are secured about engagement members 312 , e.g., by tying. Engagement members 312 may be any structure suitable for the intended purpose of releasably receiving filaments 500 , such as a hook.
[0064] As seen in FIGS. 9A-9B , in an alternate embodiment, locking structure 308 includes channels 310 and a locking mechanism 318 . Locking mechanism 318 includes a locking member 320 having an aperture 322 formed therein, a handle portion 324 , and a biasing member 326 . Aperture 322 is configured to receive filaments 500 and handle portion 324 is configured for manual engagement by the user to facilitate the transition of locking mechanism 318 between a locked condition ( FIG. 9A ) and an open condition ( FIG. 9B ). In the locked condition, aperture 322 is in misalignment with channel 310 such that a portion 508 of filament 500 is disposed between the housing 300 and the locking member 320 , effectively prohibiting any movement of filaments 500 and thereby maintaining the second condition of elongated member 400 . When locking mechanism 318 is in the open condition, however, at least a portion of aperture 322 is aligned with channel 310 such that filament 500 may freely extend therethrough. Biasing member 326 urges locking mechanism 318 towards the locked condition and may be comprised of any structure or mechanism suitable for this intended purpose, e.g., a spring.
[0065] In alternative embodiments, locking mechanism 318 may comprise a single locking member 320 and a single biasing member, or a plurality of locking members engagable with one or more biasing members 326 .
[0066] Referring again to FIGS. 6-7 , the use and function of seal member apparatus 10 will be discussed during the course of a typical minimally invasive procedure subsequent to the formation of incision 12 in the patient's tissue “T”.
[0067] Prior to the insertion of apparatus 10 , elongated member 400 is in its first condition such that distal-most end 408 of elongated member 400 may be inserted into incision 12 . The user then advances apparatus 10 distally until flange 304 abuts tissue “T”. Thereafter, the user draws filaments 500 proximally, thereby transitioning elongated member 400 into its second condition and forming tissue engaging portion 416 . The user may then secure filaments 500 to locking structure 308 to thereby maintain the second condition of elongated member 400 and anchor apparatus 10 within incision 12 . Surgical object “I” may then be inserted into and advanced distally through lumen 402 of elongated member 400 to carry out the surgical procedure through apparatus 10 . It should be noted that the insertion of surgical object “I” may dilate elongated member 400 outwardly, thereby forcing tubular braid 404 outwardly along transverse axis “B” and into tighter engagement with tissue “T”, thereby further securing apparatus 10 and enhancing the quality of the seal formed by the engagement of tissue “T” with flange 304 and tissue engaging portion 416 .
[0068] After completing the procedure and withdrawing surgical object “I”, filaments 500 may be disengaged from locking structure 308 , e.g., untied, such that elongate member may return to its initial condition. Apparatus 10 may then be withdrawn from incision 12 and incision 12 may be closed.
[0069] Referring now to FIGS. 10A-10B , in another embodiment, apparatus 10 further includes a membrane 510 that is disposed about elongated member 400 . Membrane 510 may be composed of any suitable biocompatible material that is at least semi-resilient in nature and substantially impervious to fluids, e.g., blood or insufflation gas. The incorporation of membrane 510 may facilitate the insertion and passage of one or more surgical objects “I” into and through lumen 402 of elongated member 400 , and may constitute the means by which filaments 500 are secured to elongated member 400 . Membrane 510 may be disposed about elongated member 400 along its entire length, or in the alternative, membrane 510 may be selectively disposed about individual sections of elongated member 400 , e.g. proximal section 410 , intermediate section 412 , and/or distal section 414 .
[0070] When disposed about proximal section 410 of elongated member 400 , membrane 510 engages the patient's tissue “T” upon the transition of elongated member 400 from the first condition ( FIG. 10A ) into the second condition ( FIG. 10B ) thereof. The engagement of membrane 510 with tissue “T”, in conjunction with flange 304 of housing 300 , creates a substantially fluid-tight seal about incision 12 , thereby substantially preventing the escape of any fluids, e.g. blood or insufflation gas, if any, about apparatus 10 .
[0071] As previously discussed with respect to the embodiment of FIGS. 6-7 , the introduction of surgical object “I” to elongated member 400 forces tubular braid 404 outwardly along transverse axis “B”. In the embodiment of FIGS. 10A-10B , membrane 510 would also be forced outwardly and into tighter engagement with tissue “T”. Accordingly, membrane 510 may act to further anchor apparatus 10 within tissue “T” and tighten the seal created therewith by tissue engaging portion 416 and flange 304 .
[0072] Although the illustrative embodiments of the present disclosure have been described herein with reference to the accompanying drawings, the above description, disclosure, and figures should not be construed as limiting, but merely as exemplifications of particular embodiments. It is to be understood, therefore, that the disclosure is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the disclosure. | The present disclosure relates to a surgical apparatus for positioning within an incision in tissue. In one aspect of the present disclosure, the surgical access apparatus includes an elongated seal member configured to removably receive at least one surgical object, and a deployment member. In another of the present disclosure, the surgical access apparatus includes a housing configured to removably receive at least one surgical object, an elongated member, and at least one filament. A method of percutaneously accessing an underlying surgical work site using the surgical apparatus is also disclosed. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to water tight sealing between the concrete walls of septic tanks and like subterranean concrete vessels, and pipes which pass through the walls for carrying effluent therethrough. More specifically it relates to the design of a seal which is embedded in the concrete wall during casting of the concrete wall, that seals against any one of a variety of septic pipes that are used in the trade, including straight walled, corrugated, and schedule 40 pipe.
2. Description of the Prior Art
It is difficult to obtain a thorough, and long lasting seal between the concrete wall of a septic tank and a pipe that is inserted through the wall by way of the seal.
This is especially so when the pipe is of the heavy duty corrugated variety. The seal must permit a series of major and minor diameter ridges of the pipe pass through the seal without damage to the seal wiper when the pipe is installed in the septic tank, and seal thoroughly against the pipe at any place along the length of the pipe that the installer desires. The seal should not apply significant axial bias on the pipe which may cause it to shift after installation, because the person installing the system moves out of reach of the pipe after it is passed through the seal, and the seal should remain water tight even though the pipe may shift during refill of the septic system trench in which the septic pipe runs.
Many designs of cast in concrete seals for septic pipes have been developed in an attempt to solve the above problems.
U.S. Pat. No. 3,787,061 patented Jan. 22, 1974 by R. E. Yoakum describes a hollow walled ring of flexible elastomeric material, the hollow wall being trapezoidal in cross section. The radially outward facing wall of the ring has a pair of circumferential radially outward facing tangs. The ring is cast into the concrete wall peripheral to the opening through the wall to a depth in the wall to which the concrete encloses the tangs, the radially outward facing wall, and the front and back side walls of the ring.
The inner facing wall of the ring has a pair of extending, tapering, annular ribs which straddle the center of the inner facing wall and project obliquely from the inner facing wall, inwardly and toward the front and back opening of the seal.
The outer facing wall of the ring has a hole for inserting a one-coil spring from one end of the spring, into the hollow ring in order to snake it around within the hollow ring. After installation of the spring, the two ends of the spring extend from the hole and are accessible by the user by way of an axial passageway in the concrete adjacent to the outer facing wall.
The spring constricts upon the inner wall of the hollow ring, from within the hollow ring, biasing the inner wall toward a pipe that is inserted through the seal. This presses the oblique tapered annular ribs against the pipe.
As the oblique ribs diverge, it could be difficult to insert the pipe from either end of the seal. In order to ease entry of the pipe into the seal, the operator accesses the ends of the spring via the axial passageway in the concrete, and squeezes the ends of the spring to release the constricting force of the spring on the inner wall.
U.S. Pat. No. 3,813,107, patented May 28, 1974, by J. Ditcher, describes a hollow walled ring of flexible elastomeric material, the ring having the general configuration of a capital A in cross section, but with slightly splayed legs.
The ring is cast into the concrete wall peripheral to the opening through the wall to a depth in which the wall encloses the legs and is level with the top of the cross bar of the A shape. The apex of the A that remains above the concrete yields to the pipe, forming a hollow, slightly splayed over, oval seal against the pipe as the pipe is pushed through the seal.
U.S. Pat. No. 4,103,901, patented Aug. 1, 1978, by J. Ditcher, describes an assembly which is described here as seen in cross section, in order, from the periphery toward the center of an annulus of flexible elastomeric material. It is a radially oriented T with a bulbous bottom end, followed by a first oblique leg extending beyond one side of center line, followed by a reverse angled second oblique leg which crosses back to the other side of center line, ending in a bulbous termination. The bulbous termination is an O-ring which grips the pipe that is inserted through the seal. The T with bulbous bottom end is fully embedded in the concrete. Because the O-ring has little latitude for expansion and may resist insertion of the pipe, a temporary lubricated nose cone of frustoconical shape is sometimes placed on the pipe before it is inserted through the O-ring. If the pipe is smaller than the O-ring, a stainless steel tension band may be placed over the second oblique leg to clamp it around the pipe.
U.S. Pat. No. 4,350,351, patented Sep. 21, 1982, by A. E. Martin, describes an assembly which is described here in cross section, taken in order, from the periphery toward the center of an annulus of flexible elastomeric material. It is a first bead, a second bead of the same diameter as the first bead, a short radial leg about the same length as the bead diameter. The first and second beads, and about one half of the short leg are embedded in the concrete. An oblique leg about three and one half times the length of the short radial leg is attached to the short leg. The oblique leg is directed about 60 degrees from the radial away from the pipe receiving opening of the seal. The end of the oblique leg has an integral bead with a reverse curl toward the back of the leg. The reverse curl holds a hollow core ring that is preferably glued to the reverse curl.
When the pipe is pushed into the seal it contacts the front of the oblique leg, the oblique leg is forced outward whereby the leg becomes parallel to and in intimate contact over its full length with the outer wall of the pipe, and the hollow core ring becomes sandwiched between the reverse curl and the inner wall of the opening through the concrete. The sandwiched ring increases pressure of the leg against the pipe to make a firmer seal on the pipe.
U.S. Pat. No. 4,333,662, patented Jun. 8, 1982 by W. D. Jones, describes an annulus of flexible elastomeric material which is described here as seen in cross section, taken in the direction from a hollow ring in sealing contact with the pipe, toward the outer radial periphery of the seal assembly. It is the hollow ring a short radial connector leg attached to a pyramidal base with surfaces that diverge at a dihedral angle of about 140 degrees relative to one another. The diverging elastomeric surfaces protect the pipe from being damaged by the concrete surface of the opening. The lower portion of the base is cast into the concrete which forms the opening through the wall. Additional legs extend, one from each side of the base, and cover the remaining concrete on the inward facing surface of the opening through the wall. Each leg then folds back inward in a V, where the outer leg of the V is also cast in the concrete.
U.S. Pat. No. 4,342,462, patented Aug. 3, 1982 by J. Carlesimo, describes an annulus of flexible elastomeric material which is an outer cylindrical housing that fits within the opening of the concrete housing and has a radially outward extending element embedded in the concrete. A first cylindrical wall having a diameter that is smaller than the diameter of the cylindrical housing and having a first end and a second end is attached by the first end to one end of the housing and extends axially beyond the housing. A second cylindrical wall having a diameter that is smaller than the diameter of the first cylindrical wall is attached to the second end and extends axially away from the cylindrical housing. A strap around the second wall clamps the second wall around pipe that extends through the housing.
U.S. Pat. No. 5,286,040, patented Feb. 15, 1994 by N. W. Gavin, describes an annulus of flexible elastomeric material comprising an outer cylindrical wall that fits within the opening in the concrete housing and has a radially outward extending element embedded in the concrete during the casting of the concrete housing. The outer tubular wall further has an inward depending, frustoconical wall. The smaller diameter end of the frustoconical wall seals against the pipe. A diaphragm attached to the annular edge of the smaller diameter end and sealing over the smaller diameter end has different diameter tear out rings so that various size openings can be made at the smaller diameter end to seal around various diameter pipes. In casting the seal in the concrete wall of the housing, the seal is mounted by the frustoconical wall of the seal, on a frustoconical plug which is mounted on a movable portion of the wall of the mold. Axially extending pins on the diaphragm engage the smaller diameter face of the frustoconical plug and align the seal about the axis of the cylindrical wall in a preferred rotational position. U.S. Pat. No. 4,951,914, patented Aug. 28, 1990 by Meyers et al., describes an annulus of flexible elastomeric material comprising an outer cylindrical wall that fits within an opening in a wall of a concrete housing and has a radially outward extending element embedded in the concrete during the casting of the concrete wall of the housing. The outer cylindrical wall has an inward depending, frustoconical wiper attached by the larger diameter end to one end of the cylindrical wall. The smaller diameter end of the frustoconical wiper extends into the cylinder and seals against the pipe.
In casting the seal in the wall, a frustoconical plastic mandrel bolted on a swing out portion of the mold wall seats in the frustoconical wiper of the seal. The mandrel has, at the radially outward edge of the smaller diameter end, a gripper portion which releasably frictionally retains the free end of the frustoconical wiper wall from one side during casting of the seal assembly in the concrete wall of the housing. An annular knock out plug or plate, rests against the smaller diameter end of the mandrel within the confines of the outer cylindrical wall ill order to prevent entry of liquid concrete into the space between the outer cylindrical wall and the frustoconical wiper.
Although prior art inventions may serve the purposes for which they were intended, there are still problems which must be solved if a full feature embedded in concrete septic tank seal for pipes is desired.
For example, an oblique sealing element may not line up with the ribs on some pipes. Space between a pair of oblique ribs varies with constrictive pressure on the pipe because of the oblique angles. Ribbed pipe may interfere with the full seating of each rib of a plurality of sealing ribs against the pipe. A seal element that splays over to one side or the other as the pipe is pushed through the seal may not follow into the minor diameter of the ribs of a ribbed pipe. A closely supported O-ring seal may not follow completely, or yield sufficiently, to the contour of a corrugated pipe as it is thrust through the seal. An auxiliary clamp or spring which must be adjusted may add unacceptable inconvenience or cost to installation of the pipe in the subterranean concrete vessel on the job site.
SUMMARY OF THE INVENTION
It is one object of the invention to provide an embedded in concrete pipe seal for septic systems that provides a watertight seal against the outer surface of a pipe of uniform diameter.
It is another object of the invention that the embedded in concrete pipe seal provides a watertight seal against the outer surface of a corrugated pipe.
It is another object that the seal prevents leakage of water from within the subterranean concrete vessel to the surrounding earth.
It is another object that the seal prevents leakage of water water from surrounding earth into the subterranean concrete vessel.
It is another object that the seal protects the pipe against damage from the concrete of the opening through which the pipe passes.
It is another object that the seal can support the weight of the buried pipe without damage to the seal body or leakage.
It is yet another object of the invention that sealing between the vessel and the pipe remains effective if the angle between the pipe and vessel changes after installation due to characteristic settling of the septic system concrete vessel and piping.
It is still another object that sealing assembly of the pipe in the concrete vessel wall opening can be done easily, without special tools, aids or need for special skill or dexterity.
Other objects and advantages will become apparent to one reading the ensuing description of the invention.
An elastomeric seal for Sealing a pipe through a concrete wall includes a cylindrical housing having a central axis and anchor means adapted for being east in the concrete wall so that there is a water tight seal between the concrete wall and the cylindrical housing.
A first cylindrical wall being of generally uniform diameter, and concentric with the central axis, is attached at one end to the inner side of the cylindrical housing, and has the other end extending axially into the cylindrical housing.
A second generally radial annular wall has a radially outward side attached to the first end of the first wall, is generally normal to the first wall, and comprises means for sealing against a pipe inserted through the cylindrical housing.
The housing and the first cylindrical wall comprise a cylindrical slot between them generally concentric with the first wall.
The second wall comprises, radially inward of the first wall, reversible fastening means for reversibly fastening the elastomeric seal to a mold of a concrete wall for a vessel, the reversible fastening means comprising an axial pin having a snap protrusion adapted for engaging an opening on the mold.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention be more fully comprehended, it will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a fragmentary perspective view of an underground septic tank system having the present invention.
FIG. 2 is a cross section view taken at 2--2 of FIG. 1, of a portion of the concrete septic tank of the septic tank system, incorporating the present invention cast in concrete pipe seal.
FIG. 3 is a cross section view of the seal of FIG. 2 receiving corrugated septic system pipe.
FIG. 4 is a cross section view of the seal of FIG. 2 holding corrugated septic system pipe.
FIG. 5 is a cross section view of another cast in concrete seal of the present invention.
FIG. 6 is a cross section view of another cast in concrete seal of the present invention, holding schedule 40 pipe.
FIG. 7 is a cross section view taken at 7--7 of FIG. 1, of a portion of the concrete distribution box of the septic tank system, incorporating the present invention cast in concrete pipe seal.
FIG. 8 is a cross section view of a seal of the present invention, held in the mold for casting the vessel wall with the opening through the wall and the seal in the opening, integral with the wall.
FIG. 9 is a front view of the seal of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before explaining the invention in detail, it is to be understood that the invention is not limited in its application to the detail of construction and arrangement of parts illustrated in the drawings since the invention is capable of other embodiments and of being practiced or carried out in various ways. It is also to be understood that the phraseology or terminology employed is for the purpose of description only and not of limitation.
In FIG. 1, septic tank system 20 is installed and buried below ground 24 in installation pit 26. The system includes two concrete vessels, septic tank 28, and distribution box 30.
Plastic pipe 34 carries waste from house 38 to vessel 28 where it is digested. Liquid for distribution to the septic fields (not shown) by the distribution box rises to the top of vessel 28, and is delivered to vessel 30 by way of pipe 42. The liquid is then distributed to the septic fields by vessel 30 by way of pipes 46, 48, 50, 52, and 54. Pipe 42 is connected to vessel 28 by way of cast in concrete seal 60 in concrete wall 62 of vessel 28.
Pipe 42 is supported by the earth upon which it rests at the bottom of installation pit 26, and by seal 60. Seal 60 is subjected to great stress from misalignment of the pipe, settling of the earth which also supports the vessels, and backfill, the dumping of earth back into the pit in order to bury the septic tank system.
Referring now to FIG. 2 and a preferred construction of a cast in concrete seal according to the invention, molded flexible elastomeric seal 60 is and bored by annular flange 64 into the concrete 68 surrounding opening 70 through wall 62. Seal 60 is cast into the wall, and is part of the mold which defines opening 70, as will be explained later.
A water tight seal between seal 60 and concrete 68 is established by intimate contact of the concrete with wall 88 and with annular flange 64.
Cylindrical slot 80 is located preferably within cylindrical wall 88 so that inward facing side 90 of wall 88 is straight and of uniform diameter. Cylindrical walls 96, 98, and 100 are concentric with each other and axis 110 of wall 88.
Radial walls 102 and 104 each are generally normal (90 degrees) to axis 110.
Seal 60 receives pipe 42 from outside the vessel by insertion in direction 116.
Referring to FIGS. 3 and 4, corrugated pipe 120 is inserted in seal 60 in direction 116. An inserted pipe applies radially outward biasing force 126 via annular interface 124 between the seal and the pipe, to the seal walls which cooperate to resist the outward biasing force and provide radially inward sealing force 128 via interface 124 against the pipe. Walls 96, 102, 100, and 104 respond in different, interrelated ways.
Wall 96 having a long fulcrum arm and a relatively small radial thickness, contributes a moderate sealing pressure. Having a relatively long length compared to the radial thickness of cylindrical slot 80, wall 96 arcs outward readily, yet remains generally parallel to cylindrical wall 88. The ratio of length to thickness of slot 80 is greater than unity, preferably greater than 5 to 1.
Wall 102, having a radial thickness equal to radial height 132, has high resistance to diametric expansion. It expands normal to axis 110, contributing a first level of high sealing force, until slot 80 is closed, whereupon wall 102 provides a higher level of sealing force. Wall 102 can also crush, and rotate slightly about annular connecting joint 136.
Wall 102 can operate as an annular interface 124, as shown in FIG. 6. This is done by inserting a screw driver in weakened annular separation ring 138 and prying away elements of the seal radially inward of ring 138. The seal may include concentric or asymmetrical annular separation rings. Details of the rings and how they work are described in U.S. Pat. No. 5,286,040 by Gavin. U.S. Pat. No. 5,286,040 is hereby incorporated by reference.
Wall 100 arcs outward, having a lower radial thickness than wall 102 or 104, provides a moderate sealing force, and provides room for diametric expansion of wall 104.
Wall 104 is shown in FIGS. 3 and 4, operating as an annular interface 124. It is shown operating as an annular interface 124 on a major diameter 142, and on a minor diameter 144.
Having a radial thickness equal to radial height 152, wall 104 has high resistance to diametric expansion. It expands normal to axis 110, contributing a high sealing force. Wall 104 can also crush, and rotate slightly about annular connecting joint 156.
Cast in concrete seal 160 in FIG. 5 has annular interfaces 164 and 168 provided by radial walls 172 and 174 respectively, which apply a higher total sealing force on pipe 176.
Referring to FIGS. 1, 7, and 9, cast in concrete seal 180 holds pipe 54 in asymmetrical opening 184 through the seal, of radial wall 186. The asymmetrical opening was provided by removing section 192 of the seal within weakened annular separation ring 196. Locating the pipe closer to cylindrical wall 200 which is directly supported by the concrete wall 204 provides better support for the pipe and better drainage from the distribution box.
In FIG. 8, seal 180 is in a mold for casting the seal with the wall. Steel plate 220 defines the inner facing side of wall 204. Steel plate 224 defines the outward facing side of wall 204, and pivots outward on bearing 228. A similar arrangement for the plates is seen in U.S. Pat. No. 5,286,040.
Support core 230 is designed to hold the present invention seal for positioning it between the steel plates. As axial lengths of the cylindrical walls and radial heights of the radial walls may vary between various models of the seal of the present invention, support core 230 must be able to hold the seal in a consistent manner from seal to seal. For this purpose, a reversible fastening means is provided on an radial wall that is normal to the axis of the seal, spaced inward from the axial walls of the seal.
Reversible fastener snap protrusion 234 holds the seal on core 230 by engaging holes 238 on radial wall 240 of the core. Preferably the reversible fastening means is combined with an orienting means such as pin 244 to position asymmetrical sections of the seal as desired with respect to the bottom of the concrete wall.
Although the present invention has been described with respect to details of certain embodiments thereof, it is not intended that such details be limitations upon the scope of the invention. It will be obvious to those skilled in the art that various modifications and substitutions may be made without departing from the spirit and scope of the invention as set forth in the following claims. | A cylindrical housing anchored in the opening of a concrete wall has a first cylindrical wall of generally uniform diameter attached to the inner side of the cylindrical housing and extending axially into the housing, a second generally radial annular wall has a radially outward side attached to the first wall and seals against a pipe through the cylindrical housing. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to a type of digital voice switch which is generally used in voice communication channels to detect speech in the presence of noise. In particular, the present invention relates to a digital voice switch which employs a speech detector having a variable speech threshold level, a noise detector having a variable noise threshold level, a disabling detector having a fixed maximum threshold level and a threshold adjustment circuitry which provides rapid adjustment of the speech and noise threshold levels.
Voice switches are known in the art as devices which distinguish between vocal sounds and noise carried by a communications channel. Devices of this nature have a number of known uses. For example, in a communication system which includes n voice input channels and m voice output channels, where m<n, voice switches are used to determine when there are vocal sounds on any of the n input channels. Only those channels carrying vocal sounds at any instant are connected to an output channel. Clearly, the acceptable performance of the communication system depends upon the ability of the voice switches to recognize speech in the presence of noise and to establish and maintain a communications link between the input and output channels. A failure to detect speech signals may result in excessively long clipping of speech utterances and cause user dissatisfaction. Another important function of voice switches is to prevent noise signals from activating the communication channel during the silence intervals in speech so that optimum system loading may be achieved.
Previously known voice switches use various techniques to distinguish between noise and speech signals. The earliest and simplest prior art voice switches employ a detector having a fixed threshold level to compare digitally encoded samples of a signal on a channel with the fixed threshold level. If the samples of the signal are above the threshold level, it is assumed the signal represents voice. If the samples of the signal are equal to or below the threshold level, it is assumed that the signal represents noise. Typically, the voice detector detects speech by detecting a given number of consecutive samples in excess of the threshold value. Detection of four samples in sucession has been considered suitable.
Many vocal sounds result in a signal having an amplitude which tapers off toward the end of the sound. Should the amplitude fall below the threshold level, the described voice switch would be turned off before the completion of the sound and result in a clipped speech pattern. To prevent clipping of the trailing portion of transmitted sounds, the voice switch would be constructed to operate with a hangover time. For example, when speech is detected, the voice switch is turned on to pass the detected samples of the channel signal. Once turned on, the voice switch will remain on for a hangover period to insure passage of all samples of the sound. Typically, the prior art voice switches have a hangover time of 150 milliseconds.
Clipping of the front end of the speech segment may also occur because in certain vocal sounds the amplitude of the leading portion of the signal is low. To avoid front end clipping, all samples of the signal are delayed a fixed period of time, say 4 milliseconds, after the samples are received at the input of the voice switch to permit ample time for the detection of speech. After the delayed period, the samples are applied to the output of the voice switch which actually controls the passage of speech samples and the blockage of noise and other non-speech samples. Consequently, the voice switch would detect speech prior to the time the leading portion of the speech signal arrives at the output. Thus, clipping of the front end of the speech signal is minimized.
The described prior art threshold voice switches have many disadvantages. For example, because the amplitude of speech signals varies from speaker to speaker, the prior art voice switches cannot accurately distinguish the speech of low level talkers from channel noise. Moreover, the prior art switches may clip speech if the amplitude of the low level speech signals falls below the fixed threshold. The value of the threshold usually is set at a level which is a compromise between a high level, yielding minimum noise triggering, and a low level, yielding maximum speech detection. Another disadvantage exists because noise on a typical communication channel also varies over a considerable range and a high noise level could trigger the voice switch during the silence intervals in speech. The transmission of noise will use available channel capacity and increase system loading.
To overcome the shortcomings of the fixed threshold systems, voice switches having a variable threshold level have been introduced which adjust the threshold level to the correct level that yields maximum noise immunity and maximum sensitivity to speech. One such system is disclosed in U.S. Pat. No. 3,832,491 filed Aug. 27, 1974, issued to Joseph A. Sciulli et al. and assigned to the assignee of the present application. The invention discloses a voice switch having a digital adaptive threshold generating device. The threshold level is varied in accordance with the loudness of the talker by comparing the number of times the threshold is exceeded over a given period with a reference number. Maximum and minimum threshold levels are also provided to prevent the threshold level from rising too high when there is continuous talking by a loud talker and from falling too low when there is continuous silence.
Another type of prior art voice switches having a variable threshold is taught in the U.S. Patent application Ser. No. 606,828, filed Aug. 21, 1975, filed by Raymond H. Lanier and assigned to the assignee of the present invention. In the application of Lanier the threshold is shifted in response to changes in the noise level itself. This invention is based upon the recognition that over a given interval of time "T" speech will appear as random talk spurts separated by periods of silence, while noise (generally Gaussian distributed) will be continuous. This difference between speech and noise makes it possible to detect the noise level with respect to the voice switch threshold. To detect noise, a time interval T is divided in equal subintervals τ. The number of samples that exceed the threshold in each subinterval is then counted. If the values of samples tend to be non-uniform over the interval T, then it is assumed that active speech is present. If, on the other hand, the values of samples tend to be uniform over the time interval T, then it is assumed that noise is present. In the latter case, when the number of samples accumulated during τ is large, the threshold level would be raised, whereas when the number of samples accumulated is small, the threshold level would be lowered. To maintain the threshold level just above the noise level, a threshold zone is provided wherein the zone is varied to cause the peak of the noise level to be above a minimum level of the zone but below a maximum level of the zone.
In the prior art variable threshold voice switches described above, the adjustment time initially required to increase or decrease the threshold level, and subsequently to vary the threshold level in response to a change in noise level, is relatively slow. The delay in system response resulting from these adjustments results in unsatisfactory switch performance. Another problem with the described systems is that the voice threshold level, when adjusted to uniform noise samples, is positioned too close to the noise level. Consequently, high noise pulses which are present in normal telephone line noise, quite often exceed the voice threshold level and cause false triggering of the voice switch.
SUMMARY OF THE INVENTION
The present invention relates to a variable threshold digital voice switch which detects speech signals in the presence of noise in communications channels. The present invention is designed to overcome the disadvantages of previously known voice switches by providing:
a greater immunity to false detection of noise;
a faster threshold adjustment in response to varying noise levels;
a simplification in design; and
a minimization of speech clipping.
The voice switch of the present invention employs three threshold detectors and a threshold adjustment circuitry. In particular, the voice switch provides a speech threshold detector having a high speech threshold level T H to detect the presence of speech, a noise threshold detector having a low noise threshold level T L to detect the presence of noise, a threshold adjustment circuitry operating in conjunction with the noise threshold detector to detect the noise level and to position T H and T L according to the noise level, and a disabling threshold detector having the maximum threshold level T M to disable the threshold adjustment circuitry when speech is present. The threshold levels of T H and T L are variable while the threshold level of T M is fixed. The threshold adjustment circuitry operates at a high speed and is capable of performing rapid adjustment of T H and T L in response to varying noise levels.
The voice switch of the present invention is designed to operate in a digital communications system which transmits voice signals in digital form. The voice signals are first sampled and encoded into digital form before they are applied to the input of the voice switch. The input samples are applied to a delay device which delays the application of the samples to the output of the voice switch for a fixed period of time. This delay provides a buffer against clipping of the front end of the speech burst and allows ample time for detection of speech.
The speech threshold detector having T H as the speech threshold level is provided to detect the presence of speech and operates as follows. The input samples, which are applied to the delay device, are also applied to the input of the speech detector and the magnitude of the samples is compared with the speech threshold level T H . When three consecutive samples are detected to be greater in magnitude than T H , speech is determined to be present. The three consecutive sample period, instead of the conventional four consecutive period, is utilized as the basic decision interval for detecting speech signals because experimentation has revealed that on any given speech waveform the speech threshold level for three consecutive sample detection would be positioned further above the noise level than the level for four consecutive sample detection without sacrificing any speech detection capability. This means that the present invention having a higher threshold level T H than the conventional systems would yield greater noise immunity. Upon detecting speech, the speech detector applies an output signal to the output of the voice switch and causes it to be turned on. When the voice switch is turned on, it will permit the passage of the speech samples which are delayed by the delay device. Once the voice switch is in the "on" state, it will remain on for a hangover period, which is set at a fixed period of time, approximately 170 milliseconds, to minimize clipping of the trailing portion of the speech burst. The hangover period is set only after the detection of the last three consecutive speech samples in a speech burst. Of course, for a long speech burst, the voice switch will remain on without interruption for so long as consecutive speech samples are detected in the speech detector.
The noise threshold detector having T L as the noise threshold level is provided to detect the presence of noise. The input samples, which are applied to the delay device and the input of the speech threshold detector, are also applied to the input of the noise detector. The magnitude of the samples is compared with the noise threshold level T L . Each time the magnitude of a sample exceeds T L , the noise detector produces an output signal representing the presence of noise. The threshold adjustment circuitry operates in conjunction with the noise detector to detect the noise level and to simultaneously adjust the speech and noise threshold levels according to the noise level. To accomplish the threshold adjustment, the output signals from the noise detector are accumulated over a given interval of time i. During the period of time i, the number of signals (Ni) is accumulated. If the accumulation Ni is greater than a first predetermined percentage x of the total number of samples, which indicates that T L is below the noise level, both T H and T L are increased by a fixed increment. T H is separated by a fixed distance Δ above T L . If the accumulation Ni is less than a second predetermined percentage y of the samples, which indicates that T L is above the noise level, T H and T L are decreased by the same increment. In this manner the threshold levels T H and T L are adjusted until Ni is within a desired range which is between x% and y% of the total number of samples during the sampling period of i. For example, a range between 3.3% and 5% is found to be suitable. At this range, T L is positioned near the noise level and T H is positioned just slightly above the noise level. At this position, the speech threshold level T H is far enough above the noise level to screen out most of the noise signals, yet low enough to detect low-level speech signals.
Since the noise level changes from time to time, the positions of T H and T L are constantly adjusted according to the changes in the noise level. Because the input samples are continuously applied to the input of the noise detector, the level of noise is periodically measured by accumulating over time i, the number of signals (Ni) which exceed the noise threshold level T L . The positions of T H and T L are then adjusted accordingly until Ni is within the desired range. At this range, T L and T H are again properly adjusted with respect to the new noise level.
The adjustment time required by the voice switch of the present invention for the initial adjustment when an idle channel becomes active or for the threshold levels to react to a change in noise is only dependent upon the time needed to detect the noise level and the time required to adjust T L and T H until T L is positioned near the noise level. Compared with the prior art variable threshold noise detectors, the adjustment circuitry of the present invention operates at a much faster rate and thus provides a better switching performance than the previously known detectors.
It is known that in a typical communications channel the noise appears punctuated by spurts of speech. During active speech, the speech samples that are applied to the input of the noise detector will greatly increase Ni and will cause the thresholds to be misadjusted to high levels. To overcome the incorrect adjustments during the presence of speech, the disabling threshold detector having T M as the disabling threshold level is employed to disable the threshold adjustments of the T H and T L while speech is present. T M is fixed at a level which is high enough so that it will not be exceeded by typical noise level and yet is low enough so that it will be easily exceeded at least once during a speech burst. When T M is exceeded and the hangover is placed in an ON state due to detection by the speech threshold that three consecutive samples have exceeded T H , all threshold level adjustments are disabled and will remain disabled for the entire duration of the hangover period.
BRIEF DESCRIPTION OF THE DRAWINGS
The specific nature of the invention, as well as other objects, aspects, uses, and advantages thereof, will clearly appear from the following description and from the accompanying drawing, in which:
FIG. 1 is a graphical representation showing the positions of the speech threshold level T H , the noise threshold level T L and the disabling threshold level T M with respect to the noise and speech levels.
FIG. 2 is a block diagram of the preferred embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The effectiveness of a voice switch is dependent upon the placement of a speech threshold level with respect to the speech and noise levels. Ideally, the speech threshold level should be positioned just above the noise level to maximize sensitivity to speech signals and remain immune to false triggering caused by high level noise signals. Since noise on a typical communication channel varies over a considerable range of levels, it also is critical to adjust the speech threshold level according to changes in noise level.
The voice switch of the present invention utilizes a speech detector having a variable speech threshold level T H to detect the presence of speech, a noise detector having a variable noise threshold level T L to detect the presence of noise, a threshold adjustment circuitry operating in conjunction with the noise detector to measure the noise level and to adjust the threshold levels T H and T L and a disabling detector having a fixed disabling threshold level T M to disable the adjustment circuitry when speech is present. An illustration of the positions of the speech threshold level T H , the noise threshold level T L and the disabling threshold level T M with respect to the speech and noise levels is shown in FIG. 1. To position the level T H just above the noise level, it is necessary to periodically measure the noise level and correspondingly adjust T H . As illustrated in FIG. 1, the speech threshold level T H is maintained at a fixed distance Δ above the noise threshold level T L , where T H = T.sub. L + Δ. (A preferred value for Δ for a particular code is given below; for example, for the code contemplated in the example described herein, a delta value corresponding to seven binary steps may be utilized.) To measure the noise level, the noise detector and the threshold adjustment circuitry are employed, wherein the number of samples Ni, which exceed the variable noise threshold level T L , is accumulated over a given interval of time i. A time interval of 150 milliseconds is determined to be sufficient. If Ni is greater than say 5% of the total number of samples in the time interval, both T L and T H are increased by a step increment so that the number of samples above T L will be reduced. If Ni is less than say 3.3% of the samples, the levels of T L and T H are similarly reduced thus causing an increase in the number of noise samples above T L . The threshold levels are adjusted until Ni falls within the range between 3.3% and 5% of the total number of samples or is approximately equal to 4% of the samples. When Ni is approximately equal to 4% of the total number of the samples, the speech threshold T H is thus properly adjusted to the optimum position which is slightly above the noise level and yet low enough to detect low level speech signals.
The disabling threshold T M is also employed in the present invention to disable the threshold adjustment circuitry while speech is present. As shown in FIG. 1, T M is set to a fixed level, say -23dBmO, which is considerably above a typical line noise level and yet low enough to be exceeded at least once during a speech burst.
The preferred embodiment of the digital voice switch which accomplishes the foregoing results is illustrated in FIG. 2. As is conventional in a digital communications channel which transmits voice information in digital format, the analog voice information is applied to a conventional encoder wherein the analog signals are sampled, typically, at an 8-KHz rate, and subsequently encoded into an 8-bit digital sample. As well known in the art, the 8-bit samples comprising 7 amplitude bits and 1 sign bit are applied to the input of the digital voice switch. The 8-bit samples, indicated as SIGN, B 1 , B 2 , . . . , B 7 , are applied in parallel by the input lines shown generally at 1. The switching portion of the digital voice switch comprises 8 parallel front end delay units, shown generally at 3, which consist of serial shift registers clocked at the sampling frequency of 8kHz.
The shift-registers of the front end delay 3 have a sufficient number of stages to provide a 4 millisecond delay to allow ample time for speech detection which will be explained below and thus provide a buffer against clipping of the leading portion of speech signals. The outputs of the delay units 3 are fed directly to output AND gates shown generally at 5. The output AND gates are turned on to pass voice samples when speech signals are present in the communication channel. The output gates are turned off to block the passage of non-voice or noise samples when non-voice signals are present in the channel.
The magnitude bits, B 1 , B 2 , . . . , B 7 , of the input samples of lines 1 also are applied to a speech threshold detector 7. A digital representation, TH1 - TH7, of the threshold level, also is applied to the detector 7 by lines 6. Lines 6 are connected to and fed back from a portion of the threshold adjustment circuit which will be explained below. Since the threshold level will always be positive, it is not necessary to provide a sign bit for the digital threshold value. The speech threshold detector may consist of a conventional comparator constructed in a well known manner as an operational amplifier. The comparator digitally compares the magnitude of the sample represented by the signals in lines 1 with the magnitude of the speech threshold level represented by the signals in lines 6 (TH1 - TH7). The comparator in the speech detector generates a binary 1 output if the magnitude of the sample exceeds the threshold level and a binary 0 output if the magnitude of the sample is equal to or less than the threshold level. The binary outputs from the threshold detector 7 are clocked by an 8 kHz clock into a 3-bit shift serial register 9. When the shift register 9 is completely filled with three binary 1 bits indicating that three consecutive samples exceed the threshold level, the outputs of the shift register will be all binary 1 and will energize AND gate 11. Thereupon, the AND gate 11 applies a binary 1 output to the triggering input of a one-shot multivibrator 13. If the shift register 9 is not filled with all binary 1 bits, the AND gate 11 will not be energized indicating that speech is not present or is no longer present in the communication channel.
The one-shot 13 is a conventional retriggerable device having a fixed time pulse width which provides a hangover time. The hangover time may be set at a time period typically between 150 and 180 milliseconds. Thus, the output of the one-shot 13 will rise to its active level upon triggering and will drop to its non-active level say 170 milliseconds after the last received trigger. The active output of the one-shot device 13 energizes the output AND gates 5 to pass the delayed speech samples to the output terminal.
If the AND gate 11 is not energized because the speech detector fails to detect three consecutive samples exceeding the threshold level, the one-shot 13 will not be triggered to its active level and the output AND gates 5 will not be turned on. Consequently, the AND gates 5 will block the passage of the delayed non-voice samples.
If a long and high amplitude speech burst is present in the communication channel, all of the samples of the speech signal probably will exceed the speech threshold level and only consecutive binary 1 outputs will be generated by the speech detector 7. Thus, the shift register 9 will be continuously filled with binary 1 bits and the one-shot 13 will be in the active state for as long as speech is detected to be present in the channel. The output AND gates 5 will be turned on to pass the entire speech burst without any interruption and will remain on for the period of the hangover time after the detection of last three consecutive speech samples.
Except for the introduction of the 3-bit shift register 9 in place of the conventional 4-bit shift register, the voice switch described thus far is conventional. The major improvement provided by the subject invention is in the apparatus for adjusting the speech threshold level according to the changes in the noise level and in the device for disabling the threshold adjustment circuitry when speech is present.
To adjust the level of the speech threshold detector 7 according to the noise level in the input channels, the subject invention employs a noise threshold detector 15 and a threshold adjustment circuitry 16. As shown in FIG. 2, the magnitude bits, B 1 , B 2 , . . . , B 7 , of the input samples in lines 1 are simultaneously fed to the noise threshold detector 15 as well as to the speech threshold detector 7. The noise threshold detector 15 may consist of a conventional comparator constructed in a well known manner as an operational amplifier. The comparator compares the magnitude of the input samples in lines 1 with a noise threshold level indicated as TL1 - TL7 in lines 14, which are connected to and fed back from a portion of the threshold adjustment circuitry 16 which will be explained below. The comparator provides a binary 1 at its output if the input sample exceeds the threshold level and a binary 0 if the input sample is equal to or less than the threshold level. The threshold adjustment circuitry 16 is comprised of an accumulator 17, comparators 19 and 21, a counter 25 and an adder 27. The outputs from the noise threshold detector 15 are applied to the input terminal of the accumulator 17, which may be a conventional counter or shift register. The accumulator 17 counts the number of binary 1 outputs received from the noise detector 15 during a given period of time, say 150 milliseconds. The accumulator is reset to zero every 150 milliseconds by a 6.67 Hz clock signal. The output of the accumulator 17 is applied to the inputs of two comparators 19 and 21. Comparators 19 and 21 are conventional devices which compare the state of the accumulator 17 with preset numbers. In the specific example described, comparator 19 compares the accumulated number with a fixed number, 60, which represents 5% of the total number of samples in the 150-millisecond interval. If the accumulated number is greater than 60, the comparator output provides a binary 1 to one of two inputs of an AND gate 23. The other input to the AND gate 23 is connected to a latch 33 which performs the disabling function and will be explained below. When both inputs of the AND gate 23 receive binary 1 inputs, gate 23 is enabled and passes a binary 1 output to the count-up input of the up-down counter 25. Similarly, comparator 21 compares the accumulated number with a fixed number 40, which represents 3.3% of the total samples in the 150-millisecond interval. If the accumulated number is less than 40, comparator 21 provides a binary 1 output to one of two inputs of an AND gate 24. The other input to the AND gate 24 is connected to the latch 33 which will be explained below. When both inputs of the gate 24 receive binary 1 inputs, gate 24 is enabled and passes a binary 1 output to the count down input of the up-down counter 25. If neither of the two conditions is met or when the accumulation is ≧ than 40 and ≦ than 60, then gates 23 and 24 will not be enabled. When the latter condition occurs, it represents that the noise threshold level as indicated by signals in lines 14 is properly positioned with respect to the noise level and no adjustment is needed.
It will be appreciated from the foregoing that the count in the accumulator 17 is the number Ni of the samples which exceed the noise threshold level, as indicated by signals in lines 14, in the time interval i. Although the time interval i may be any desirable period of time, a time interval i of 150 milliseconds is used as an example in explaining the preferred embodiment of the present invention. Comparators 19 and 21 determine whether the accumulation Ni is in one of the three following ranges:
1st range: Ni > 60
2nd range: Ni < 40
3rd range: 40 ≦ N≦ 60
The first two ranges indicate that the noise threshold level is positioned either too low or too high, respectively, whereas the third range indicates that the threshold level is properly positioned with respect to the noise level.
After determining the relative position of the noise threshold level, appropriate adjustment to the noise threshold level in the noise detector 15 and speech threshold level in the speech detector 7 is carried out. If the count up or count down input of the up-down counter 25 is active during the 6.67 Hz clock pulse, which indicates that the accumulation Ni is greater than 60 or less than 40, then the value of the noise threshold level, TL1 - TL7, applied at the input of the counter 25 is increased or decreased, respectively, by one quantization step in the binary form. The output of the up-down counter 25, which now contains the adjusted value, TL'1 - TL'7, of the noise threshold level, is applied to the input of the counter 25, to the input of the noise threshold detector 15 and to the input of an adder 27 by lines 14. As mentioned in the foregoing, the speech threshold level of the detector 7 is maintained at a fixed distance Δ above the noise threshold level and is adjusted simultaneously with the noise threshold level, the adder 27 is employed to carry out the aforementioned adjustment function. When the adjusted value of noise level, TL'1 - TL'7, is applied to the adder 27, a Δ value represented by seven binary steps is added thereto from lines 28 to generate a new speech threshold value TH'1 - TH'7. As shown in FIG. 2, the new TH'1 - TH'7 value is applied by the output of the adder 27 by lines 6 to the speech threshold detector 7 to adjust the speech threshold level to its optimum position, which is slightly above the noise level.
If the up-down counter 25 is inactive indicating that Ni is in the third range and that the noise threshold level is properly positioned with respect to the noise level, no adjustments to the noise threshold level and speech threshold level is carried out.
To disable the speech and noise threshold adjustment circuitry while speech is present, a third disabling threshold detector 29 is employed. As illustrated in FIG. 2, the magnitude bits of the input samples on lines 1 are simultaneously fed to the disabling threshold detector 29, as well as to the speech threshold detector 7 and noise threshold detector 15. Another input to the disabling threshold detector 29 is connected to lines 30. Lines 30 are connected to a source of disabling signals which represents a fixed disabling threshold level. The disabling threshold level may be set at any desirable amplitude level which is high enough so that it is exceeded at least once during a speech burst. In the present invention, a level represented by the number 60 in binary form, which is equivalent to a threshold value of -23.0 dBmO, is found to be suitable. The disabling threshold detector 29 may consist of a conventional comparator, which is constructed in a well known manner as an operational amplifier. The comparator compares the magnitude of the input samples in lines 1 with the fixed threshold value in lines 30. When the magnitude bits of the input sample are determined to be greater than the threshold value, a binary 1 is applied to one input of a NAND gate 31. The NAND gate 31 is comprised of two inputs and one output. The other input to the NAND gate 31 is applied by line 32 from the one shot multivibrator 13 in the speech detection circuitry. If the input from the hangover one shot 13 is also active, then the NAND gate 31 applies an output of a binary 0 to the negative triggering preset input of a latch 33. If either the sample fails to exceed the disabling threshold level or the one-shot 13 is in the inactive state, or if both conditions exist, the NAND gate 31 applies an output of a binary 1 to the preset input of the latch 33. The latch 33 may consist of a conventional latch flip-flop or a latch switch comprising two negative triggering inputs. As shown in FIG. 2, the latch 33 contains preset and clear inputs. The latch is preset when a binary 0 from the output of the NAND gate 31 is applied at the preset input of the latch 33. The latch then outputs a binary 0 to the input of AND gates 23 and 24 of the threshold adjustment circuit 16 by means of an adjustment enable line 35. The application of binary 0 to the AND gates 23 and 24, representing that the disabling detector 29 is exceeded by a speech sample and that speech is detected in the speech detector 7, results in prohibiting any adjustment to the speech and noise threshold levels. If the NAND gate 31 subsequently applies a binary 1 output to the preset input of the latch 33 and the output from the hangover one-shot 13, which is applied to the clear input of the latch, is active, representing a condition when speech is detected to be present but the speech samples fail to exceed the disabling threshold level, the latch will remain in the preset state and will continue to produce a binary 0 input until the hangover period is over or until the one-shot 13 becomes inactive. Consequently, the speech and noise threshold adjustments are disabled by the latch 33 for the entire duration of the speech burst even though portions of the speech burst may fall below the fixed threshold level of the disabling threshold detector 29.
If the one-shot 13 becomes inactive, either before or after the latch is preset by a binary 0 input from the output of the NAND gate 31, the output from the one-shot will cause the latch to provide a binary 1 output to the AND gates 23 and 24. Thus, the speech and noise threshold adjustments are enabled by the latch 33 when speech is not detected to be present in the communication channel.
From the foregoing, it will be apparent that the embodiments shown are only exemplary and that various modifications can be made in construction and arrangement within the scope of the invention as defined in the appended claims. | A digital voice switch for detecting speech signals in the presence of noise on a communication channel. The voice switch employs a threshold adjustment circuitry and three threshold detectors which include a speech detector, a noise detector and a disabling detector. The speech detector having a variable speech threshold level detects the presence of speech signals in the communication channel. The noise detector having a variable noise threshold level detects the presence of noise. The threshold adjustment circuitry, which is capable of providing rapid threshold adjustment, operates in conjunction with the noise detector to detect the noise level and to adjust the speech and noise threshold levels according to the level of the noise present in the communication channel. The disabling detector having a fixed maximum threshold level operates to disable the function of the threshold adjustment circuit while speech is present. | 6 |
[0001] This application is a divisional of U.S. patent application Ser. No. 12/061,030, filed on Apr. 2, 2008, (now pending) which claims benefit of U.S. Provisional Patent Application Ser. No. 60/921,601, filed on Apr. 3, 2007. The teachings of U.S. patent application Ser. No. 12/061,030 and U.S. Provisional Patent Application Ser. No. 60/921,601 are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] Drilling fluids (muds) are normally used in drilling oil and gas wells. These fluids are used to maintain pressure, cool drill bits, and lift cuttings from the holes as the well is being drilled. Drilling fluids vary greatly in composition depending upon specific requirements of the well being drilled as well as geological considerations. However, drilling fluids typically fall into the class of aqueous formulations or oil-based formulations.
[0003] Early oil-based drilling fluid formulations that are no longer used were typically comprised of the following ingredients: oil (generally No. 2 diesel fuel), emulsifying agents (alkaline soaps and fatty acids), wetting agents (dodecylbenzene sulfonate), water, barite or barium sulfate, (weighting agent), asbestos (employed as viscosification agent) and/or, amine-treated clays (also as viscosification agent). These oil-based drilling fluid formulations were generally formulated based primarily on amount of barite added. For example, such a typical drilling fluid could range in specific gravity from about 7 pounds per gallon up to 17 pounds per gallon or even greater. This variation in specific gravity is primarily controlled by the amount of barite added.
[0004] Oil-based drilling fluid formulations perform adequately in a number of applications, primarily those where the use of oil-based drilling fluids is dictated by the lack of stability of the formation in which drilling is taking place. For example, in various types of shale formation, the use of conventional water-based fluids can result in a deterioration and collapse of the shale formation. The use of the oil-based formulations circumvents this problem. However, traditional oil-based drilling fluid formulations also have some significant disadvantages. One disadvantage is that the incorporation of asbestos or asbestos fines can result in significant health problems, both during the fluid formulation and potentially during the subsequent use of such formulations. Therefore, in recent years there has been a strong push to reduce the level of asbestos used in such formulations or to eliminate the use of asbestos completely. The use of substitutes for asbestos as viscosity enhancing agents in such application has not been universally successful by virtue of the fact that the replacement must maintain adequate viscosities under the drilling conditions which can involve high temperature and high shear conditions.
[0005] As noted in U.S. Pat. No. 4,425,463, there has been a substantial need for a drilling fluid which would exhibit good performance at high temperatures in water sensitive formations. Past experience has shown that oil-based drilling fluids can provide good performance in water sensitive formations, and the state of the art systems can perform well at temperatures of up to about 350° F. (177° C.). In cases where the viscosity of conventional oil-based drilling fluids break down during drilling operations additional viscosifier is added to the drilling fluid being circulated into the well. In other words, the problem of viscosity loss during drilling is traditionally circumvented by the addition of more viscosifier to the drilling fluid being circulated into the well. While this solution is adequate at moderate temperatures the degradation of the viscosifier can be so rapid at high temperatures, such as those encountered in drilling geothermal wells and natural gas wells, that cost of utilizing the amount of additional viscosifier required can become cost prohibitive. There is accordingly a need for oil-based drilling fluids that can maintain their viscosity and gel strength at temperatures of 400° F. (204° C.) or even higher.
[0006] U.S. Pat. No. 4,525,522 describes an approach to viscosification of oil-based drilling fluids which permits the substitution of latices of sulfonated ionomers for asbestos fines and amine clays. These resulting polymer-modified drilling fluids are reported to display improved low temperature rheological properties which include improved gel strength at up to temperatures of 400° F. (204° C.) and higher, based on tests conducted for 16 hours at such temperatures.
[0007] U.S. Pat. No. 4,525,522 more specifically discloses latices of sulfonated thermoplastic polymers which function as viscosification agents when added to oil-based drilling fluids which are the fluids used to maintain pressure, cool drill bits and lift cuttings from the holes in the drilling operation for oil and gas wells. The sulfonated thermoplastic polymer of these latices contain about 5 to about 100 meq. of sulfonate groups per 100 grams of the sulfonated thermoplastic polymer, wherein the sulfonated groups are neutralized with a metallic cation or an amine or ammonium counterion. U.S. Pat. No. 4,525,522 further reports that a polar cosolvent can optionally be added to the mixture of oil drilling fluid and sulfonated polymer, wherein the polar cosolvent increases the solubility of the sulfonated polymer in the oil drilling fluid by decreasing the strong ionic interactions between the sulfonate groups of the sulfonated polymer.
[0008] U.S. Pat. No. 4,447,338 discloses that sulfonated EPDM is very effective as a viscosifier for oil-based drilling fluids. U.S. Pat. No. 4,447,338 more specifically discloses an oil base drilling fluid which comprises: (a) an organic liquid selected from the group consisting of a diesel fuel, kerosene, fuel oil and crude oil; (b) about 1 to about 10 parts by weight of water per 100 parts by weight of the organic liquid; (c) about 20 to about 50 lb/bbl of at least one emulsifier; (d) weighting material of sufficient quantity necessary to achieve the desired density; and (e) about 0.25 to abut 2 lb/bbl of a water insoluble neutralized sulfonated elastomer, said neutralized sulfonated polymer elastomer having about 5 to about 30 meg. of sulfonate groups per 100 grams of the neutralized sulfonated polymer elastomer, said neutralized sulfonated elastomer being derived from an elastomeric polymer selected from the group consisting of EPDM terpolymers and butyl rubber, said EPDM terpolymers having a number average molecular weight of about 10,000 to about 200,000 and said butyl rubber having a Staudinger molecular weight of about 20,000 to about 500,000.
[0009] U.S. Pat. No. 4,425,463 discloses the use of mixtures of sulfonated thermoplastic polymers and amine-treated clays as viscosification agents for utilization in oil-based drilling fluids. U.S. Pat. No. 4,425,463 muse specifically discloses a oil-based drilling fluid which comprises: (a) an organic liquid immiscible with water; (b) about 1 to about 10 parts by weight of water per 100 parts by weight of the organic liquid; (c) about 20 to about 50 lb/bbl. of emulsifier; (d) weighting material necessary to achieve the desired density; (e) about 0.25 to about 4.0 lb/bbl. of water insoluble neutralized sulfonated thermoplastic polymer having about 5 to about 100 meq. of sulfonate groups per 100 grams of the neutralized sulfonated thermoplastic polymer; and (f) about 1 to about 10 lb/bbl. of an amine-treated clay.
[0010] U.S. Pat. No. 5,021,170 discloses an invert emulsion drilling fluid comprising a liquid oleaginous medium, water, an emulsifier and a gellant comprised of sulfonated ethylene/propylene/5-phenyl-2-norbornene terpolymer and an organophilic clay. U.S. Pat. No. 5,021,170 more specifically reveals a oil-based drilling fluid comprising: (a) a liquid oleaginous phase; (b) a polar liquid phase, said oleaginous phase being present in an amount of from about 30 to about 98% by volume of the liquid phase, said polar liquid phase being present in an amount of from about 2 to about 70% by volume of the liquid phase; (c) an emulsifier; and (d) a gellant comprising a sulfonated ethylene/propylene/5-phenyl-2-norbornene terpolymer having a number average molecular weight of about 5,000 to about 300,000; and an organophilic clay comprising the reaction product of an organic onium compound and a smectite clay, the weight ratio of said organophilic clay to said terpolymer being from about 6:1 to about 20:1, said gellant being present in an amount sufficient to viscosify said oleaginous medium to the desired degree.
[0011] As has been noted, it is frequently important for the viscosification agents employed in drilling fluids to provide the desired level of viscosity at high service temperatures for extended periods of time. It is also critical for drilling fluids to provide the desired service characteristics, such as maintaining pressure, cooling drill bits and to lift cuttings from the hole being drilled, without causing formation damage. For instance, formation damage can be caused by organoclays used in conventional drilling fluids plugging the pores of rock formations. Good filtration behavior is another characteristic that it is desirable for drilling fluids to exhibit. A low level of the drilling fluid being lost in the rock formation is indicative of good filtration behavior. Finally, it is desirable for the viscosification agent to provide the desired increase in viscosity at a relative low concentration in the drilling fluid. There has been a long felt need in the well drilling industry for an improved drilling fluid that exhibits all of these desirable characteristics.
SUMMARY OF THE INVENTION
[0012] This invention is based upon the finding that certain chlorosulfonated α-olefin copolymers can be beneficially utilized in drilling fluids that are utilized in drilling subterreanean wells. For instance, it has been unexpectedly found that certain chlorosulfonated α-olefin copolymers can be beneficially used as total or partial replacements for organoclays in oil based drilling fluids. The utilization of chlorosulfonated α-olefin copolymers in oil-based drilling fluids offers (1) long service life at high operating temperatures, (2) minimal formation damage, (3) improved filtration behavior, and (4) highly effective performance at low viscosifier levels. Additionally, the chlorosulfonated α-olefin copolymers utilized in the practice of this invention are soluble in conventional drilling fluid formulations which reduces the level of mixing required in preparation of the drilling fluid formulation. This makes the preparation of the drilling fluid easier, faster, and less energy intensive. The chlorosulfonated α-olefin copolymers used in the practice of this invention are copolymers of ethylene and an α-olefin that contains from 4 to about 8 carbon atoms. These chlorosulfonated α-olefin copolymers typically contain from about 0.2 weight percent to about 5 weight percent sulfur and can optionally be reacted with water to yield a sulfonic acid or reacted and neutralized with a base, such as sodium hydroxide, to yield a sodium sulfonated copolymer. The chlorosulfonated α-olefin copolymers used in making the drilling fluids of this invention are also free flowing powders which makes them easier to handle than the sulfonated EPDM (ethylene-propylene-diene monomer rubbers) crumbs employed in the drilling fluids of the prior art.
[0013] The present invention more specifically discloses an oil-based drilling fluid which is comprised of: (a) an organic liquid; (b) water; (c) an emulsifier; (d) a wetting agent; (e) a fluid loss reducing agent; (f) a weighting material; and (g) a chlorosulfonated α-olefin copolymer which is comprised of repeat units that are derived from ethylene and an α-olefin that contains from 3 to about 20 carbon atoms.
[0014] The subject invention further reveals a process for drilling a well into a subterranean formation which comprises boring a hole into the earth by rotary drilling, wherein an oil-based drilling fluid is circulated down a drilling pipe and returned to the surface of the earth through a pipe hole annulus, wherein the oil-based drilling fluid is comprised of (a) an organic liquid; (b) water; (c) an emulsifier; (d) a fluid loss reducing agent; (e) a weighting material; and (f) a chlorosulfonated α-olefin copolymer which is comprised of repeat units that are derived from ethylene and an α-olefin that contains from 3 to about 20 carbon atoms.
[0015] The present invention also discloses a natural resource system comprising: (a) a subterranean formation; (b) a wellbore penetrating at least a portion of the subterranean formation; (c) a casing positioned within at least a portion of the wellbore; and (d) drilling fluid present in at least a portion of the area between the surface of the wellbore and the outside surface of the casing, wherein the drilling fluid is comprised of (a) an organic liquid; (b) water; (c) an emulsifier; (d) a fluid loss reducing agent; (e) a weighting material; and (f) a chlorosulfonated α-olefin copolymers which is comprised of repeat units that are derived from ethylene and an α-olefin that contains from 3 to about 20 carbon atoms.
[0016] The subject invention further reveals a process for making an oil-based drilling fluid formulation which comprises mixing (a) an organic liquid; (b) water; (c) an emulsifier; (d) a wetting agent; (e) a fluid loss reducing agent; (f) a weighting material; and (g) a chlorosulfonated α-olefin copolymer which is comprised of repeat units that are derived from ethylene and an α-olefin that contains from 3 to about 20 carbon atoms, to produce the oil-based drilling fluid formulation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is graph of viscosity as a function of shear rate for the drilling fluid formulations made in Examples 1-6.
[0018] FIG. 2 is graph of viscosity as a function of shear rate for the drilling fluid formulations made in Examples 7-11.
[0019] FIG. 3 is graph of viscosity as a function of shear rate for the drilling fluid formulations made in Examples 12-16.
DETAILED DESCRIPTION OF THE INVENTION
[0020] The present invention relates to improved oil-based subterranean fluids that utilize chlorosulfonated α-olefin copolymers as their viscosification agent. These oil based fluids can be employed in drilling oil wells, gas wells, geothermal wells, and other types of wells into subterranean formations. In these oil-based fluids the organoclay, asbestos, sulfonated thermoplastic, and/or sulfonated EPDM that would typically be used in the formulation as the viscosification agent is replaced partially or totally with the chlorosulfonated α-olefin copolymer. Conventional oil-based drilling fluids formulations into which the chlorosulfonated α-olefin copolymer can be substituted as the viscosification agent are described in U.S. Pat. No. 4,425,463, U.S. Pat. No. 4,525,522, and U.S. Pat. No. 5,021,170. The teachings of U.S. Pat. No. 4,425,463, U.S. Pat. No. 4,525,522, and U.S. Pat. No. 5,021,170 are incorporated herein by reference for the purpose of describing oil-based drilling fluids into which the chlorosulfonated α-olefin copolymers of this invention can be incorporated as the viscosification agent.
[0021] The oil-based drilling fluids of the instant invention are typically comprised of an organic liquid such as an oil, fresh water or salt water, an emulsifier, a weighting material and the chlorosulfonated α-olefin copolymer. The drilling fluid formulation can also include a wide variety of other additives and also typically include a wetting agent. In general, the oil-based drilling fluid will have a specific gravity of about 7 pounds per gallon (0.839 kg/liter) to about 20 pounds per gallon (2.397 kg/liter), more preferably about 10 (1.198 kg/liter) pounds per gallon to about 16 pounds per gallon (1.917 kg/liter), and most preferably about 12 pounds per gallon (1.438 kg/liter) to about 18 pounds per gallon (1.917 kg/liter). A typical oil-based drilling fluid is comprised of an oil, about 0 to about 40 parts by weight of water per 100 parts by weight of the oil. The drilling fluid will preferably contain about 5 to about 30 parts by weight of water per 100 parts by weight of the oil. The drilling fluid will most preferably contain about 5 to about 20 parts by weight of water per 100 parts by weight of the oil. The drilling fluid will also typically contain 0 ppb (pounds per barrel) to about 20 ppb of an emulsifier and/or supplementary emulsifier and about 0 ppb to about 20 ppb of a wetting agent.
[0022] A weighting material (barium sulfate or barite) will also typically be included at the level necessary to give the desired fluid density. The weighting material will normally be included in the drilling fluid formulation at a level of less than about 800 ppb, more preferably about 5 ppb to about 750 ppb, and most preferably about 10 ppb to about 700 ppb. Some representative examples of weighting materials that can be used include barium sulfate, barite, hematite, and calcium carbonate. In many cases it is preferred to use barium sulfate or barite as the weighting material.
[0023] The chlorosulfonated α-olefin copolymer will typically be included in the drilling fluid formulation at a level which is within the range of about 0.1 ppb to about 10 ppb. The chlorosulfonated α-olefin copolymer will more typically be included in the drilling fluid formulation at a level which is within the range of about 0.5 ppb to about 6 ppb. The chlorosulfonated α-olefin copolymer will preferably be included in the drilling fluid formulation at a level which is within the range of about 1 ppb to about 4 ppb. The chlorosulfonated α-olefin copolymers will most preferably be included in the drilling fluid formulation at a level which is within the range of about 1 ppb to about 3 ppb.
[0024] The oil employed in the oil-based drilling fluids of this invention can be an aromatic oil or an aliphatic oil. Thus, the oil can have a relatively high aromatic content, such as No. 1 diesel fuel, No. 2 diesel fuel, kerosene, jet fuel, and the like. However, the α-olefin copolymers of this invention offer the advantage of being capable of being used in making drilling fluid formulations with aliphatic oils having a low aromatic content. Some representative examples of base oils that can be used include paraffin, iso olefin, α-olefin, Low Toxicity Mineral Oil (LTMO), ester, Diesel.
[0025] Some representative examples of suitable emulsifiers which can be employed in making the drilling fluids of this invention include soaps of fatty acids, such as magnesium or calcium soaps of fatty acids, fatty acid derivatives including amino-amines, polyamides, polyamines, esters (such as sorbitan monoleate polyethoxylate, sorbitan dioleate polyethoxylate), imidaxolines, and alcohols.
[0026] Typical but non-limiting examples of suitable wetting agents that can be utilized include lecithin, fatty acids, crude tall oil, oxidized crude tall oil, organic phosphate esters, modified imidazolines, modified amidoamines, alkyl aromatic sulfates, alkyl aromatic sulfonates (alkylaryl sulfonates), and organic esters of polyhydric alcohols.
[0027] Typical but non-limiting examples of weighting materials which can be employed in the drilling fluids of this invention include barite, barium sulfate which may optionally be surface-treated with other cations, such as calcium, iron oxide, gelana, siderite, and calcium carbonate.
[0028] The chlorosulfonated α-olefin copolymers used in the practice of this invention can be of three genres:
[0029] (1) A chlorosulfonated ethylene copolymer comprising 0.5 to 10 weight percent chlorine, 0.25 to 5 weight percent sulfur and a plurality of —SO 3 M groups, wherein M is a cation, said chlorosulfonated copolymer produced from a linear olefin copolymer comprising copolymerized units of 45 to 80 weight percent ethylene and 55 to 20 weight percent of an alpha-olefin having 3 to 20 carbon atoms, said linear olefin copolymer having a melt flow ratio, I 10 /I 2 , of at least 4 and a ratio of Mw/Mn less than 3.5.
[0030] (2) A chlorosulfonated ethylene copolymer comprising 0.5 to 10 weight percent chlorine, 0.25 to 5 weight percent sulfur and a plurality of —SO 3 H groups, said chlorosulfonated copolymer produced from a linear olefin copolymer comprising copolymerized units of 45 to 80 weight percent ethylene and 55 to 20 weight percent of an alpha-olefin having 3 to 20 carbon atoms, said linear olefin copolymer having a melt flow ratio, I 10 /I 2 , of at least 4 and a ratio of Mw/Mn less than 3.5.
[0031] (3) A chlorosulfonated ethylene copolymer containing between 0.5 and 10 (preferably between 0.75 and 6, most preferably between 1 and 3) weight percent chlorine and between 0.25 and 5 (preferably between 0.35 and 3, most preferable between 0.5 and 2) weight percent sulfur and a plurality of SO 2 Cl + groups.
[0032] These chlorosulfonated copolymers are made in a solution process by reacting a polyolefin base polymer with a chlorosulfonation agent.
[0033] The polyolefin base polymers employed in the process of this invention include various ethylene/alpha-olefin copolymers. This includes traditional Ziegler-Natta linear low density polyethylene (LLDPE) and metallocene derived ethylene alpha-olefin copolymers. The alpha-olefin may be any unbranched alpha-olefin containing between 3 and 20 carbon atoms. Octene-1, butene-1 and propylene are preferred alpha-olefins. The copolymers may be semi-crystalline or amorphous. Semi-crystalline copolymers are preferred because they are easier to handle. Optionally, more than one polyolefin base polymer may be added to the reactor so as to result in a chlorosulfonated blend of polyolefin polymers.
[0034] These chlorosulfonated copolymers are made in a solution process (meaning that the polyolefin base polymer is dissolved in a solvent) by reaction with a chlorosulfonation agent selected from the group consisting of i) Cl 2 and SO 2 and ii) sulfuryl chloride (SO 2 Cl 2 ).
[0035] An azo initiator (e.g. Vazo® 52 available from DuPont) is introduced and the reactor purged with an inert gas (e.g. nitrogen) to remove oxygen. After adjusting the temperature of the solution to between 50° C. and 75° C. (preferably 55° C. to 60° C.), chlorine gas, sulfur dioxide and additional initiator is introduced to the reactor. When a desired level of chlorosulfonation has occurred, the reaction mass is degassed with nitrogen, followed by application of a vacuum. Optionally, an epoxide, e.g. Epon® 828 (available from Hexion Specialty Chemicals), is added to stabilize the product. Also optionally, an antioxidant, e.g. Irganox® 1010 (available from Ciba Specialty Chemicals) is added to protect the polymer during isolation and storage. The SO 2 Cl 2 chlorosulfonation process differs from the Cl 2 /SO 2 process in that sulfuryl chloride and an amine activator rather than chlorine gas and sulfur dioxide along with an azo initiator, is employed to chlorosulfonate the polyolefin base polymer.
[0036] Alternately, the chlorosulfonated copolymer solution can be utilized to prepare a partially neutralized aqueous emulsion of chlorosulfonated polymer salts [—SO 3 M] that can be isolated directly from solution as a dry polymer.
[0037] In the practice of this invention the drilling fluid will be prepared by mixing the various ingredients thereof either at the drilling site or at a remote location for delivery to the drilling site. In either case, as the well is being drilled the drilling fluid will be continuously circulated down the drill pipe to the vicinity of the drilling bit and returned to the surface in the annulus. Bit cuttings generated by the rotating drill bit are carried to the surface in the drilling fluid where the fluid is processed through a shale shaker and solids separation apparatus.
[0038] The specific techniques used when employing the drilling fluid of this invention will be determined by its intended use and is analogous to methodologies employed when using prior art drilling fluids for corresponding completion or work-over operations. For example, when the drilling fluid is employed as a gravel packing fluid, it is typically injected into the formation in accordance with the procedure described in U.S. Pat. No. 4,552,215. The teachings of U.S. Pat. No. 4,552,215 are incorporated herein by reference for the purpose of teaching this drilling technique.
[0039] When employed as a fracturing fluid, the drilling fluid of this invention is usually injected into the formation using procedures analogous to those disclosed in U.S. Pat. No. 4,488,975, U.S. Pat. No. 4,553,601, Howard et al., Hydraulic Fracturing, Society of Petroleum Engineers of the American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc., New York, N.Y. (1970), and Allen et al., Production Operations, Well completions, Workover, and Stimulation, 3rd Edition, volume 2, Oil & Gas Consultants International, Inc., Tulsa, Okla. (1989) (Allen), chapter 8, these publications being incorporated herein by reference in their entirety.
[0040] When employed in a perforating operation, the drilling fluids of the present invention are normally used according to the methodologies disclosed in chapter 7 of Allen, referenced above. Techniques for using packer fluids and well killing fluids, such as those discussed in chapter 8 of Allen, are also applicable to the drilling fluids of the present invention.
[0041] This invention is illustrated by the following examples that are merely for the purpose of illustration and are not to be regarded as limiting the scope of the invention or the manner in which it can be practiced. Unless specifically indicated otherwise, parts and percentages are given by weight.
Examples 1-6
[0042] In this series of experiments oil-based drilling fluid formulations were made utilizing chlorosulfonated α-olefin copolymers having varying levels of sulfonation as the viscosification agent. These oil-based drilling fluids were compared to an identical oil-based drilling fluid formulation that was made utilizing an organoclay as the viscosification agent. All of the drilling fluids made in this series of experiments had a density of 15 ppg and an oil to water ratio (OWR) of 80:20.
[0043] The constituents employed in making these drilling fluids are identified in Table 1. The conventional oil-based drilling made with the organoclay is identified as Fluid A. The drilling fluids made with the chlorosulfonated α-olefin copolymers are identified as being Fluid B. It should be noted that the drilling fluid made with the organoclay contained 4 ppb of the organoclay. However, the drilling fluids made with the chlorosulfonated α-olefin copolymers contained only 1 ppb of the sulfonated copolymer. The chlorosulfonated α-olefin copolymers utilized in Fluid B compositions (Examples 2-6) all had the same molecular weight but contained differing levels of sulfonation (1%, 1.13%, 1.24%, 1.5%, and 1.63% sulfonation).
[0000]
TABLE 1
Component
Fluid A
Fluid B
Oil
153.5 ppb
Primary emulsifier
6 ppb
Secondary emulsifier
4 ppb
Organoclay
4 ppb
—
Viscosifier
—
1 ppb
Fluid Loss Reducer
4 ppb
Lime
6 ppb
Brine (26%)
47 ppb
Weighting agent
394.3 ppb
[0044] All of the drilling fluids evaluated in this series of experiments were aged by hot-rolling for 16 hours at a temperature of 250° F. (121° C.) before being characterized. In drilling, once the critical value or yield point (YP) of the drilling fluid is achieved, the rate of flow or rate of shear typically increases with an increase in pressure, causing flow or shearing stress. The high shear viscosity, known as plastic viscosity (PV), is similarly measured in centipoise units. In drilling fluids, yield points (YP) above a minimum value are desirable to adequately suspend solids, such as weighting agents and cuttings. A drilling fluid system preferably has a yield point of from about 10 to about 50, preferably 15 to 30 pounds per 100 square feet.
[0045] The rheological stability of a drilling fluid is monitored by measuring its yield point and gel strengths, in accordance with standard drilling fluid tests, before and after circulation down the wellbore. These standard tests, which include the tests for yield point (YP) and plastic viscosity (PV), are well known in the industry and are described in “Recommended Practice Standard Procedure for Field Testing Water-Based Drilling Fluids,” Recommended Practice 13B-1 (1st ed. Jun. 1, 1990), American Petroleum Institute (hereinafter referred to as “RP 13B-1”).
[0046] The plastic viscosity, yield point, and filtration volume (V) measured by static filtration at 300° F. (149° C.) of the drilling fluids made in this series of experiments is reported in Table 2. The viscosity characteristics of the drilling fluids made in this series of experiments is shown in FIG. 1 . As can be seen increasing levels of sulfonation increased the viscosity of the fluid as well as the shear thinning amplitude. This experiment also shows that the chlorosulfonated α-olefin copolymers could be used to attain similar viscosity characteristics to those attained using organoclays. However, the level of the sulfonated copolymer needed to achieve this objective was only about 25% of the amount of organoclay needed to attain similar viscosity characteristics.
[0047] As can be seen from Table 2, the yield point of the drilling fluids of this invention made with the chlorosulfonated α-olefin copolymers were higher than those of the conventional drilling fluid made with the organoclay. This increase in yield point was observed at every level of sulfonation evaluated. The plastic viscosities of the drilling fluids of this invention at copolymer sulfonation levels between about 1.2% and 1.5% were also higher than that observed in the case of the control made using the organoclay. Accordingly, this series of experiments shows that chlorosulfonated α-olefin copolymers can be utilized in making drilling fluids having superior characteristics. Additionally, such drilling fluids can be made utilized a relatively low level of the sulfonated copolymer.
[0000]
TABLE 2
PV, YP, and filtration volume values
Viscosifier
Organoclay
1%
1.13%
1.24%
1.5%
1.63%
PV
42
32
41
46
48
31
YP
14
25
38
44
59
80
V (ml)
5.8
4.8
7.4
7.2
9.6
9
Examples 7-11
[0048] In this series of experiments oil-based drilling fluid formulations were made utilizing varying levels of chlorosulfonated α-olefin copolymers. These oil-based drilling fluids were compared to an identical oil-based drilling fluid formulation that was made utilizing an organoclay as the viscosification agent. All of the drilling fluids made in this series of experiments had a density of 18 ppg and an oil to water ratio (OWR) of 85:15.
[0049] The constituents employed in making these drilling fluids are identified in Table 3. The conventional oil-based drilling made with the organoclay is identified as Fluid C. The drilling fluids made with the chlorosulfonated α-olefin copolymers are identified as being Fluid D. It should be noted that the drilling fluid made with the organoclay contained 2.45 ppb of the organoclay. However, the drilling fluids made with the chlorosulfonated α-olefin copolymers contained 0.5 ppb, 1 ppb, 1.5 ppb, and 2 ppb of the sulfonated copolymer. The chlorosulfonated α-olefin copolymers utilized in Fluid D compositions (Examples 8-11) were identical (had the same molecular weight and the same level of sulfonation).
[0000]
TABLE 3
Component
Fluid C
Fluid D
Oil
160 ppb
Primary emulsifier
10.5 ppb
Secondary emulsifier
7 ppb
Organoclay
2.45 ppb
—
Viscosifier
—
0.5 or 1 or 1.5
of 2 ppb
Fluid Loss Reducer
4.2 ppb
Lime
0.7 ppb
Brine (26%)
31 ppb
Weighting agent
557.3 ppb
[0050] All of the drilling fluids evaluated in this series of experiments were aged by hot-rolling for 16 hours at a temperature of 400° F. (204° C.) before being characterized. The plastic viscosity, yield point, and filtration volume (V) measured by static filtration at 350° F. (177° C.) of the drilling fluids made in this series of experiments is reported in Table 4. The viscosity characteristics the drilling fluids made in this series of experiments is shown in FIG. 2 . As can be seen increasing levels of the sulfonated copolymer increased the viscosity of the fluid without changing the shear thinning amplitude. This experiment also shows that the chlorosulfonated α-olefin copolymers could be used to attain similar viscosity characteristics to those attained using organoclays. However, the level of the sulfonated copolymer needed to achieve this objective was substantially lower than the amount of organoclay needed to attain similar viscosity characteristics. This experiment also shows that a desired viscosity for the drilling fluid can be realized by adjusting the level of the sulfonated copolymer employed as the viscosifier.
[0051] As can be seen from Table 4, the yield point and plastic viscosity of the drilling fluids of this invention were higher than those of the conventional drilling fluid made with the organoclay at sulfonated copolymer loadings of 1.5 ppb. Accordingly, this series of experiments shows that chlorosulfonated α-olefin copolymers can be utilized in making drilling fluids having excellent characteristics. Additionally, such drilling fluids can be made utilized a relatively low level of the sulfonated copolymer.
[0000]
TABLE 4
PV, YP, and filtration volume values
Viscosifier
Organoclay
0.5 ppb
1 ppb
1.5 ppb
2 ppb
PV
48
32
42
70
n.d
YP
12
8
14
30
n.d.
V (ml)
12
9.2
8
4
n.d.
[0052] It should be noted that at the 2 ppb loading level PV, YP, and V values were not determined because the fluid viscosity was too thick and therefore some of the Fann readings were out of range.
Examples 12-16
[0053] In this series of experiments oil-based drilling fluid formulations were made utilizing a combination of a chlorosulfonated α-olefin copolymer and an organoclay as the viscosification agent (see Fluid F, Fluid G, and Fluid H). For comparative purposes a drilling fluid was also made utilizing only an organoclay as the viscosification agent (Fluid E). Also, for further comparative purposes an additional fluid was made that employed only a chlorosulfonated α-olefin copolymer as the viscosification agent (Fluid I). All of the drilling fluids made in this series of experiments had a density of 18 ppg and an oil to water ratio (OWR) of 85:15.
[0054] The composition of the fluids made in this series of experiments is depicted in Table 5.
[0000]
TABLE 5
Fluid
Component
Fluid E
Fluid F
Fluid G
Fluid H
I
Oil
160 ppb
Primary emulsifier
10.5 ppb
Secondary emulsifier
7 ppb
Organoclay
2 ppb
1.5 ppb
1 pbb
0.5 ppb
—
Viscosifier
—
0.5 ppb
1 ppb
1.5 ppb
2 ppb
Fluid Loss Reducer
4.2 ppb
Lime
0.7 ppb
Brine (26%)
31 ppb
Weighting agent
557.3 ppb
[0055] The viscosity characteristics of the fluids made is shown in FIG. 3 . The plastic viscosity, yield point, and filtration volume determined for each of these drilling fluid formulations is reported in Table 6.
[0000]
TABLE 6
PV, YP, and filtration volume values
Organoclay (ppb)
Viscosifier
0/2
0.5/1.5
1/1
1.5/0.5
2/0
PV
44
49
62
96
n.d
YP
23
52
58
65
n.d.
V (ml)
12
8.4
6.2
4
n.d.
[0056] It should be noted that at the 2 ppb loading level of the sulfonated copolymer the PV, YP, and V values were not determined because the fluid viscosity was too thick and therefore some of the Fann readings were out of range.
[0057] This experiment shows that it is possible to utilize a combination of a conventional organoclay and a chlorosulfonated α-olefin copolymer as the viscosification agent.
[0058] While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. | This invention is based upon the finding that certain chlorosulfonated α-olefin copolymers can be beneficially utilized in drilling fluids that are utilized in drilling subterreanean wells. For instance, it has been unexpectedly found that certain chlorosulfonated α-olefin copolymers can be beneficially used as total or partial replacements for organoclays in oil based drilling fluids. The subject invention more specifically reveals a process for drilling a well into a subterranean formation which comprises boring a hole into the earth by rotary drilling, wherein a drilling fluid is circulated down a drilling pipe and returned to the surface of the earth through a pipe hole annulus, wherein the oil-based drilling fluid is comprised of (a) an organic liquid; (b) water; (c) an emulsifier; (d) a weighing material; (e) a fluid loss reducing agent; and (f) a chlorosulfonated α-olefin copolymer which is comprised of repeat units that are derived from ethylene and an α-olefin that contains from 4 to about 20 carbon atoms. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates generally to textile wet treatment machines and more particularly to a carrier for supporting packages of textile material during processing in a wet treatment machine such as, for example, textile yarn package dyeing machines and to a novel package retaining cap for use with such carrier.
Textile package dyeing machines normally have a cylindrical pressurizable vessel into which packages of textile material to be wet processed, e.g., yarn packages wound on cylindrical spools, are arranged in vertical stacks on supporting vertical tubes arranged in spaced relation over the interior of the dye vessel. Such dyeing machines basically are of two types, commonly referred to as vertical dyeing machines, i.e., wherein the cylindrical vessel is oriented vertically with an openable lid at the upper end of the vessel for vertical insertion and removal of yarn packages to be dyed, and horizontal dyeing machines, wherein the cylindrical vessel is oriented horizontally with an openable lid at one end for horizontal insertion and removal of yarn packages to be dyed.
In both horizontal and vertical dyeing machines, it is conventional practice to support the yarn packages on a removable carrier which, in the case of vertical machines, can be lifted and lowered and, in the case of horizontal machines, can be horizontally transported on tracks or conveyors, for inserting and removing the yarn packages into and from the dye vessel. Conventional carriers of this type basically comprise a base with a plurality of upstanding tubes mounted in a spaced arrangement to the base. Yarn packages are slidably mounted over the upper ends of the tubes in a stacked arrangement and are secured by a cap threaded onto a compatibly threaded upper end portion of each tube. The upstanding tubes are hollow and perforated and communicate with concentric openings formed through the base to permit dye liquor to flow axially through the tubes and radially through the yarn packages.
While such carriers function satisfactorily and advantageously when supporting a full capacity of yarn packages, difficulties are encountered in dyeing smaller lots of yarn packages which do not require each tube to be fully stacked with yarn packages. In such cases, it is highly undesirable to fill the dye vessel with dye liquor to the same volume utilized when dyeing a full capacity of yarn packages. Accordingly, the volume of the dye bath is reduced commensurate with the number of yarn packages actually being dyed, but, since the lesser volume of the dye bath will result in the level of the bath being below the upper end of the perforated package-supporting tubes, appropriate measures must be taken to cover the exposed perforations. Conventionally, this is accomplished in one of two manners, either by placing a tubular cover over the exposed length of each perforated tube to block the perforations in the tube or by situating one or more volumetric displacement elements within the carrier or otherwise within the dye vessel to raise the level of the lesser volume of dye liquor to the level occupied during full capacity dyeing. Disadvantageously, however, volumetric displacers increase the risks of potential contamination of the dye liquor, while the tubular covers may not fully seal the exposed perforations in the package-supporting tubes, thereby risking the possibility that may be drawn into the pump of the dyeing machine used for circulating the dye liquor.
An alternative form of textile package carrier is disclosed in pending U.S. patent application Ser. No. 08/134,912, filed Apr. 12, 1993, and now U.S. Pat. No. 5,442,939 entitled CARRIER FOR SUPPORTING TEXTILE MATERIAL IN A WET TREATMENT MACHINE. The carrier of such invention utilizes a plurality of posts extending upwardly from a carrier base with each post having a longitudinal package supporting portion adjacent the base of sufficient length to support a minimum number of textile packages and a longitudinal spindle portion extending outwardly from and in alignment with the package supporting portion. Any selected one of several available package supporting adapters of varying lengths may be placed about the spindle portion of each post, or alternatively adapters may be omitted from each spindle portion, to give the carrier the ability to selectively support differing numbers of packages about the posts as determined by the absence of, or the presence and length of, package adapters on the posts. A conventional form of package retaining cap is threadedly mounted on the spindle portion of each post and advanced along the length thereof sufficiently to rest in retaining engagement with the uppermost package mounted on the post. In this manner, the carrier is enabled to be used for wet processing operations with less than a full capacity of textile packages, but without the necessity of utilizing blocking covers or volumetric displacer elements as in the prior art.
SUMMARY OF THE INVENTION
It is a fundamental object of the present invention to further improve on the package carrier of above-described U.S. patent application Ser. No. 08/134,912 to enable even greater ability for diverse numbers of textile yarn and like material packages to be selectively supported during wet processing operations without the disadvantages of the conventional techniques described above. A specific object of the invention is to provide a novel, simplified and improved package retaining cap to replace the conventional form of threadedly mounted cap used in the prior art.
Briefly summarized, the carrier of the present invention basically includes a base and one or more post assemblies extending outwardly from the base for mounting selectively differing numbers of the textile material packages in series about each post to be centrally supported thereabout. A package retaining cap is provided for mounting on each post. According to the present invention, the cap is provided with latching means selectively movable between a disengaged condition wherein the cap is permitted to be slidably mounted to and demounted from the post for selective slidable positioning movement along the post to differing package retaining positions therealong into and out of engagement with the outermost one of the annular textile material packages supported on the post and an engaged condition wherein the cap is securely retained against unintended sliding movement along the post during a wet treatment operation.
Thus, by the selective disposition of the caps on the respective posts, the package supporting capacity of the carrier can be readily varied, in turn enabling a corresponding reduction to be achieved in the required volume of processing liquid in the wet treatment machine without risk of contamination or risk of drawing into the pump of the machine.
In accordance with the preferred embodiment of the present invention, the latching means of the cap comprises a latch plate disposed to be selectively movable between a first position in the disengaged condition of the latching means wherein the latch plate does not impede relatively free sliding movement of the cap along the post and a second position in the engaged condition of the latching means wherein the latch plate is braced against the post to prevent sliding movement of the cap along the post. Preferably, the cap comprises a base having an opening for receiving the post and the latch plate has an opening for receiving the post, the latch plate in its first position being disposed in spaced parallel relation to the base with their respective openings aligned with one another for relatively free sliding movement of the cap along the post and in its second position being disposed in a sufficiently angular relation to the base to be braced against the post at the opening in the latch plate to prevent sliding movement of the cap along the post. The respective openings in the base and the latch plate of the cap conform closely to the configuration of the post.
Preferably, the base of the carrier includes a liquid flow opening for each post and each post includes an annular mounting portion affixed to the base about the liquid flow opening for liquid communication therethrough with the annular interior of the textile packages supported on the posts. For example, in one embodiment, threaded bores in the base define the liquid flow openings and the mounting portions of the posts are in the form of threaded tubes compatibly engageable in the threaded bores.
Each post is configured to permit liquid flow axially through the annular interior of the textile packages. For example, each post may comprise a plurality of radially outwardly extending package supporting struts.
Carriers in accordance with the present invention may be appropriately configured in differing embodiments for use in either horizontal-type wet treatment machines or vertical-type wet treatment machines.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross-sectional view of a carrier for supporting textile yarn packages for insertion into a textile wet treatment machine of the horizontal dyeing machine type, in accordance with one preferred embodiment of the present invention;
FIG. 2 is a side elevational view of one post assembly of the carrier of FIG. 1;
FIG. 3 is a horizontal cross-sectional view of the post assembly of FIG. 2, taken along line 3--3 thereof;
FIG. 4 is a perspective view of one package retaining cap of the carrier of FIG. 1;
FIG. 5 is an enlarged vertical cross-sectional view taken through one post and its associated cap in the carrier of FIG. 1; and
FIGS. 6 and 7, respectively, are vertical cross-sectional views taken through one post assembly of the carrier of FIG. 1, illustrating the arrangement of the post assembly and its associated cap when the carrier is selectively filled to differing levels with yarn packages.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now the accompanying drawings and initially to FIG. 1, a carrier 10 is shown according to a preferred embodiment of the present invention adapted for supporting textile material in the form of yarn packages 12 for transport to and from a horizontal type textile wet treatment machine in the form of a horizontal package dyeing machine (not shown). As illustrated, the carrier 10 is loaded with the yarn packages 12 to less than full capacity in accordance with the present invention, as more fully described hereinafter.
As is conventional, the carrier 10 is independently movable on a conventional carrier transport assembly (not shown), preferably an arrangement of one or more conveyor belts and/or tracks, for transporting the carrier 10 to and from the dyeing machine, which may be located in an arrangement of multiple dyeing machines commonly served by the same carrier transport assembly.
The carrier 10 basically includes a base structure 14 which serves both to support the yarn packages 12 and as a liquid flow assembly for delivery and withdrawal of treating liquid, e.g., a dye liquor, bleaching solution, water wash, or other appropriate treating fluid, to and through the carrier 10. The base structure 14 is preferably rectangular in overall horizontal cross-section. An upstanding wall 16 having four substantially flat planar sides is affixed to the base structure 14 to extend upwardly from its periphery and thereby forms with the base structure 14 an enclosure 18 for retaining the treating liquid during wet treatment of the yarn packages 12 therein. The top of the carrier's enclosure 18 is open for ease of loading thereinto and unloading therefrom the yarn packages 12.
The liquid flow arrangement formed by the base structure 14 includes two liquid distribution chambers 20,22 formed within the base structure 14 and communicating with the enclosure 18 defined by the base structure 14 and the wall 16, one of the liquid distribution chambers 20,22 serving to deliver treating liquid into the enclosure 18 and the other serving to withdraw treating liquid from the enclosure. Each of the chambers 20,22 extends through substantially the full horizontal extent of the base structure 14 with the chamber 20 disposed above the chamber 22. The upper chamber 20 communicates with the enclosure 18 through openings 24 formed in the top of the base structure 14, while the lower chamber 22 communicates with the enclosure 18 through elongated passages 26 which extend from the lower chamber 22 upwardly through the upper chamber 20.
Each chamber 20,22 has end openings (not shown) at each opposite end of the base structure 14 for communicating with corresponding openings of the chambers of an adjacent carrier 10 disposed in the vessel of the wet treatment machine or, alternatively, with ports of a duct assembly formed in the machine for supplying liquid to and withdrawing liquid from the interior of the machine in a conventional manner.
The carrier 10 is equipped with a plurality of upstanding post assemblies 28, only three of which are shown in FIG. 1, which are mounted to and extend upwardly from the base structure 14 for the purpose of supporting and retaining on each post assembly 28 a stacked column of multiple yarn packages 12. The post assemblies 28 are arranged in longitudinally extending rows spaced sufficiently from one another both longitudinally and transversely within the carrier enclosure 18 to permit non-interfering vertical stacking of the packages 12 thereon.
Each post assembly 28 is mounted to the base structure 14 in a manner permitting liquid communication between the liquid flow assembly of the base structure 14 and the annular interior of the yarn packages 12. For this purpose, each post assembly 28 is constructed as shown in FIGS. 2 and 3 with a lower tubular mounting portion 30 having external threads 32 and each liquid opening 24 in the top of the base structure 14 is correspondingly threaded internally for threaded mounting of each post assembly 28 co-axially within a respective liquid opening 24 in the base structure 14 for communication through the tubular mounting portion 30 with the liquid distribution chamber 20. Each post assembly 28 has an elongate package supporting portion 34 extending substantially the full length of the post assembly 28, formed by three lengthwise struts 36 projecting radially outwardly from one another at equal angular spacings and affixed at one end co-axially to the upper annular edge of the mounting portion 30 of the respective post assembly 28, as best seen in FIG. 3.
The radially transverse dimension of the struts 36 of the package supporting portion 34 are selected to correspond to the inside diameter of a textile yarn package 12 so that a package placed about the package supporting portion 34 of any post assembly 28 will be securely supported by the struts 36 against undesirable lateral movement relative to the post assembly 28. Similarly, the lengthwise dimension of the package supporting portion 34 is selected to correspond to the stacked dimension of a certain number of the packages 12 which has been predetermined to be the maximum number of packages to be supported on each post assembly 28 during any dyeing operation. By way of example, the lengthwise dimension of the struts 36 in the illustrated embodiment is sufficient for laterally supporting a column of six stacked yarn packages 12 on each post assembly 28, although those persons skilled in the art will readily recognize that the package supporting portion 34 may be of any other selected longitudinal dimension as may be desirable.
Each post assembly 28 is provided with a packaging retaining cap 40 best seen and understood with reference to FIGS. 4 and 5. Each package retaining cap 40 includes a circular base plate 42 and a correspondingly circular top plate 44 affixed coaxially together in spaced parallel relation by a pair of connecting bars 46 affixed to and extending transversely between the respective peripheries of the base and top plates 42,44 at diametrically opposed locations thereon. Respective Y-shaped openings 48,50 are formed in alignment with one another at the centers of the base and top plates 42,44, the Y-shaped openings 48,50 being configured and dimensioned in close conformity to the struts 36 of the post assemblies 28 for sliding receipt thereof through the openings 48,50.
The cap 40 also has a fulcrum bar 52 affixed to the periphery of the base plate 42 substantially circumferentially midway between the connecting bars 46 and extending therefrom perpendicularly toward the top plate 44, but terminating at a free upper end edge 52' at a short spacing from the periphery of the top plate 44. A correspondingly circular latching plate 54 is disposed between the base and top plates 42,44, with its periphery disposed between the fulcrum bar 52 and the top plate 44 and with diametrically opposed recesses 56 in the latching plate 54 receiving the respective connecting bars 46. In this manner, the latching plate 54 is disposed for pivoting movement about the edge 52' of the fulcrum bar 52 and under the guidance of the connecting bars 46 between a release position wherein the latching plate 54 is substantially parallel to the base and top plates 42,44 in face abutment with the underside of the top plate 44, shown in broken lines in FIG. 5, and a latching position wherein the latching plate 54 extends angularly downwardly from the edge 52' of the fulcrum bar 52 into edge abutment with the base plate 42 at the diametrically opposite side of the latching plate 44, as shown in full lines in FIG. 5. A Y-shaped opening 58 is also formed in the latching plate 54 at its center to be in substantially precise alignment with the corresponding openings 48,50 in the base and top plates 42,44 when the latching plate 54 is in its release position.
As will thus be understood, each cap 40 may be readily placed slidably on and advanced slidably along the package supporting portion 34 of an associated post assembly 28 while the latching plate 54 is held in its release position. However, when the latching plate 54 is released from such position, it pivots gravitationally into the latching position, thereby angularly moving its Y-shaped opening 58 out of alignment with the corresponding openings 48,50 in the base and top plates 42,44, whereby the latching plate 54 braces against the struts 36 of the post assembly 28 to essentially lock the cap 40 at the braced location against further sliding movement along the post assembly without manual lifting of the latching plate 54 into its release position.
Hence, it will be understood that this unique construction of the cap 40 in the present invention enables each cap to be slidably mounted and demounted to and from an associated post assembly and to be moved selectively along the full length thereof to any desired latching position, which uniquely enables the carrier 10 of the present invention to operate effectively with any number of yarn packages 12 installed on its post assemblies up to the full maximum capacity of the carrier. Thus, once a stack of yarn packages 12 are placed on each post assembly 28, the package retaining cap 40 for each post assembly is slidably placed onto the package supporting portion 34 thereof and advanced therealong into retaining engagement with the uppermost package supported on the post assembly. By way of example, FIG. 1 depicts the carrier 10 with five yarn packages 12 installed on each post assembly 28, while FIGS. 6 and 7 contrastingly depict one post assembly 28 with lesser numbers of yarn packages 12, the cap 40 in each case being latched in place on the post assemblies in secure engagement with the uppermost package.
Of course, as those persons skilled in the art will readily recognize and understand, the package retaining cap 40 of the present invention may be of various alternative constructions utilizing a pivoted latching plate and substantially any configuration of aligned openings may be formed in the latching plates in correspondence to the cross-sectional configuration of the post assemblies on a carrier. For example, it is contemplated that a carrier may be equipped with post assemblies having an X-shaped cross-sectional configuration, in which case the base, top and latching plates of a cap in accordance with the present invention would be correspondingly configured with X-shaped openings. Alternatively, it is equally possible that the post assemblies of a carrier and the openings in the respective plates of a compatible cap may be formed of many various other configurations, without departing from the present invention. In each case, satisfactory operation would be accomplished so long as the latching plate pivots sufficiently to achieve bracing engagement with the post assembly. In addition, it will be recognized that the post assembly 28 could be of any desired length to handle any desired maximum number of yarn packages. These and other modifications and adaptations of the present invention are intended to be within the scope and substance of this invention.
With yarn packages 12 mounted on the post assemblies 28 in the manner described, the carrier 10 may be placed in a conventional horizontal-type textile package dyeing machine and wet processing treatment of the yarn packages 12 will proceed in essentially conventional fashion. Specifically, the treating liquid is permitted to flow freely between the upper liquid distribution chamber 20 and the axial interior area of the stacked columns of yarn packages by passing through the tubular mounting portions 30 of the post assemblies 28 and traveling along the post assemblies 28 between the struts 36 of the package supporting portion 34. Depending upon the direction of treating liquid circulation determined by the delivery and withdrawal of the treating liquid through the liquid distribution chambers 20,22, the treating liquid passes between the enclosure 18 and the annular interiors of the stacked package columns in either a radially inward or a radially outward direction. In either case, the progressive ongoing radial flow of the treating liquid through the packages 12 over the course of operation of the machine achieves the desired treatment of the yarn wound on the packages 12. The level of the treating liquid bath within the enclosure 18 can be reduced to the elevation of the cap directly above the stacked yarn packages to submerge the cap and thereby substantially prevent within the enclosure 18 above the package columns from entering the annular interior area of the stacked package columns. To facilitate such reduction of the liquid level within the carrier 10, the side wall 16 defining the enclosure 18 may be equipped with one or more removable or movable panels (not shown) by which the upper edge of the wall 16 may be effectively lowered at least one side of the carrier 10 or, alternatively, the side wall 16 could be replaceable in its entirety with another side wall of lesser height.
As will thus be understood, carriers in accordance with the present invention advantageously enable the liquid level of the treating bath within a textile package dyeing machine of either horizontal or vertical type, or any other appropriate textile wet treatment machine, to be effectively lowered to the elevation of the actual number of packages supported on the carrier whenever the carrier is loaded to less than its full capacity, without the prior necessity of utilizing any form of blocking element or volumetric displacement element and without the risk of drawing air into the pump of the treatment machine or the risk of potential contamination of the treatment bath. The cap of the present invention is especially advantageous in this regard because of its simple construction which is easy and relatively inexpensive to manufacture while also providing effective and reliable operation. In turn, the costs associated with using an excess of treating liquid and the accompanying environmental problems of reclaiming and/or disposing of used treatment liquid are effectively minimized.
It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. | Textile yarn package supporting carriers are disclosed for use in textile dyeing machines to enable the machine to be effectively operated at less than full capacity. Each carrier has a base with multiple upstanding package supporting posts each having a longitudinal package supporting portion extending upwardly from the base and dimensioned to securely support a predetermined maximum number of packages on each post. A cap mounts to the spindle portion of each post for movement therealong into engagement with the outermost package on the post. The cap has a latching arrangement with a latch plate disposed to be selectively movable between a disengaged or release position wherein the latch plate does not impede relatively free sliding movement of the cap along the post and a second engaged position wherein the latch plate is braced against the post to prevent sliding movement of the cap along the post. | 3 |
BACKGROUND OF THE INVENTION
The invention relates generally to shielding structures, and, more particularly, to such shielding structures which are capable of protecting spacecraft components from critically damaging impact with a variety of space particles having a wide range of velocities and angles of approach such as meteorites and orbital debris. The invention addresses the fact that each impact causes some degree of damage to the shield itself and this damage can range from small holes in the outer protective layers to large (several inches in diameter) holes in the underlying protective layers. The invention incorporates elements that provide some degree of protection for subsequent impacts following the widespread damage to the shield system commensurate with defeat of the "design-size" particle.
Many different types of shields have been designed for protecting many types of vehicles as well as personnel from impact with ballistic projectiles and other types of impacting particles. Many of these shields include layers of fabric bonded together. An example of such a shield is disclosed in U.S. Pat. No. 4,923,741 to Kosmo. The Kosmo shield is specifically designed for spacesuits and spacecraft and has layers of fabric composed of low density and high density material which provide micrometeorite protection, radiation protection, etc. Some of these fabric layers include aramid fibers. However, a primary disadvantage of the Kosmo shield is that although it provides for a variety of different types of protection including radiation and thermal extremes, it is incapable of providing protection against both high and low velocity particle collisions.
Other prior art shields have been designed specifically for protecting personnel, equipment and vehicles from injury and damage caused by projectiles, bomb fragments and other products of explosives. An example of such a prior art shield for suppressing or reducing penetration by such particles is disclosed in U.S. Pat. No. 3,924,038 to McArdle. The McArdle design utilizes a ceramic outer layer and nylon felt layers backed by a metallic layer. The felt layers are stitched together into a cloth-like configuration. However, a primary disadvantage of such a shield is that it provides protection only against relatively low velocity particles such as bullets. The selection of the different types of materials used in the McArdle design is specifically to allow effective shielding against a variety of shapes and sizes of particles rather than against particles having a wide range of velocities.
Another type of prior art shield design includes various shielding layers which are separated from the particular structure to be shielded. An example of such a shield is disclosed in U.S. Pat. No. 3,569,714 to Anderson. The Anderson shield provides protection from a variety of hazards including impacts with projectiles, temperature extremes and radiation. The Anderson shield includes a plurality of chambers positioned so that one is within the other and includes an open space between the outer and inner containers. However, as with the other prior art patented designs discussed hereinabove, the Anderson shield does not provide protection against a variety of high and low velocity impacting particles. Moreover, due to the particular mounting configuration and the particular shapes of the containers, the Anderson shield additionally has the disadvantage of not being able to provide protection equally from particles impacting the protected structure from all directions.
Other prior art patents for providing shielding for space and atmospheric vehicles include shells which are provided with inner walls therebetween. The inner walls define an area containing a material for providing protection against collision with projectiles. Such a shield is disclosed in U.S. Pat. No. 3,439,885 to Sackleh. The Sackleh shield incorporates bronze wool in the area and supports which are rods or ribs positioned between the outer and inner shells. The bronze wool is utilized to provide protection from low velocity projectiles. However, the outer shell is simply utilized to provide a smooth outer surface for the bronze wool which is the primary protection provided against projectile impacts. Consequently, as with the other prior art patents discussed hereinabove, the Sackleh shield does not provide protection against both high and low velocity particles.
What is therefore needed is a shield for spacecraft that provides generally complete protection against impacts from micrometeoroids and orbital debris particles having a wide range of impact velocities and angles of approach.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide a shield for protecting spacecraft from impact with particles having a relatively wide range of velocities and angles of approach.
It is also an object of the present invention to provide a shield for spacecraft which provides protection from impact with a variety of types of particles.
It is also an object of the present invention to provide a shield for spacecraft which provides protection from impact with orbital debris.
It is another object of the present invention to provide a shield for spacecraft which provides protection from impact with micrometeoroids.
Spacecraft requiring shields against impacting particles are typically provided with single layer, thin aluminum bumpers called Whipple shields for providing protection for shell structures of the spacecraft against meteoroid particles. Since the meteoroids will collide with spacecraft and the bumpers at very high velocities, the Whipple shield fragments, melts or often vaporizes the particle and thereby disperses the energy over a much larger area of the underlying structure thereby reducing the impact loading per unit area. Thus, although the spacecraft might be impacted by the debris from this collision, if the impact parameters are within the design envelope the spacecraft can remain sufficiently intact to survive. However, for new large space structures and long duration low earth orbits, the shielding must protect the spacecraft from large particle impacts over a much broader range of velocities due to the increasing prevalence of orbital debris. In addition, some of the spacecraft have vulnerable components, i.e., large pressurized tanks or pressurized habitation modules having relatively thin walls. Since these types of spacecraft will have to endure impacts with both micrometeoroid high velocity particles as well as orbital debris having relatively low velocities, the Whipple shields, which provide protection predominantly from high velocity impacts, will not be able to provide adequate protection for these types of spacecraft.
Essentially, the shield of the present invention includes three structures which, in combination, provide protection to the spacecraft from both high and low velocity particles. These structures include an outer structure or bumper which provides protection from high velocity particles such as micrometeoroids. The micrometeoroids may be traveling at speeds of up to 100 kilometers per second. The bumper is not capable of stopping impacting particles such as micrometeoroids but, depending on impact conditions and materials, either vaporizes, melts or fragments the particle as well as the bumper material. However, in the absence of other shielding structures, these residual fragments, molten materials and gases may impinge upon the underlying spacecraft structure causing some degree of damage thereto. For this reason, the shield also includes an intermediate structure, a cloud stopper which is positioned generally inward of the bumper i.e., between the spacecraft and the bumper. The cloud stopper defeats the products of multiple high velocity particles/bumper interactions. The cloud stopper is designed to resist perforation by small fragments, fracture or excessive deflection from impulsive load and backface spallation caused by intense stress waves that may propagate through the thickness of the cloud stopper. Thus, the cloud stopper prevents the products of collision between high velocity micrometeoroids and the bumper from penetrating through the shield and causing damage to the spacecraft.
The bumper and cloud stopper together provide protection against relatively high velocity impacts that are normal to the shield surface. However, the bumper and cloud stopper are relatively ineffective against relatively low velocity particles that impact normal to the shield or that are produced as a result of medium velocity impacts at oblique angles to the shield surface. Consequently, a fragment stopper is provided and positioned between the cloud stopper and the spacecraft to stop any fragments that penetrate the cloud stopper and bumper. Thus, the fragment stopper is designed to prevent penetration by low velocity particles on the order of approximately one to two kilometers per second that could easily perforate the cloud stopper and bumper. In addition, the fragment stopper also generally prevents penetration by residual low velocity fragments resulting from medium velocity oblique impacts on the bumper or incidental spall fragments ejected from the backface of the cloud stopper.
Since it is crucial both that the projectile have enough space to vaporize after impact with the outer bumper sheet and that there be enough space to spread the load of impact over a sufficient area to minimize damage to both the shield and the underlying spacecraft, a selected spacing is provided between the shield structures described hereinabove. Thus, there is a particularly well-defined optimum spacing between the individual bumper sheets as well as between the bumper sheet and the cloud stopper and the fragment stopper structures. However, practical considerations may limit the number of layers and/or the spacings between them. Such embodiments can, nevertheless, effectively combat the impact effects. The spacing is preferably provided by means of a spacer structure positioned between the bumper, the cloud stopper and the fragment stopper. Thus, the spacers provide a means for support for the shield system as well as a means for transferring the impact loads to preferred spacecraft reaction locations or hardpoints.
The bumper is preferably composed of a fibrous ceramic woven material such as a Nextel 312, an alumina-boria-silica woven fabric, manufactured by the ceramic materials department of the 3M Corporation, Building 225-4N-07, 3M Center, St. Paul, Minn. 55144-1000. The bumper may also be composed of a 99.95% silica dioxide fibrous ceramic woven material such as Astroquartz II. Alternatively, the bumper sheets may be composed of tin, each preferably in a solid sheet thereof. The projectile at high velocities melts the tin so that there are no tin fragments except for the molten tin which sprays out in a conical volume having an approximately forty five degree angle. Consequently, this prevents transferrence of a significant highly concentrated load to the underlying structure. Similarly, the Nextel or Astroquartz II uses fibrous material without inclusion of a resin, so that it is composed simply of tiny fibers in a weave. Thus, when the projectile impacts the Nextel or Astroquartz II at very high velocities, the projectile melts and therefore does not produce any fragments other than the tiny fibers of the fabric. As a result, there are no fragments which are sufficiently large to produce any significant damage to the underlying structures. The bumper preferably comprises a plurality of sheets thereof spaced apart from each other a selected distance. The spacing distance is preferably established based on the application and spacecraft design requirements i.e., impacting particle size, mass, velocity and angle of incidence.
Since the spacecraft may be composed of relatively delicate or sensitive materials or have components thereof which may be sensitive to shock, the shield is preferably not connected directly to a thin walled structure of the spacecraft. Instead, the shield is preferably connected to hardpoints such as stiffening frames or beams of the spacecraft or to bosses on pressure vessel structures, or other structures which are relatively insensitive to impact loads.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a first embodiment of the shield of the present invention showing the shield mounted on a spacecraft at hardpoint end structure portions thereof and showing a portion of the shield cut away to illustrate relative positioning of components thereof.
FIG. 2 is a cross-sectional view of the first embodiment of the present invention taken along lines 2--2 of FIG. 1 and showing the component structures thereof.
FIG. 3 is a sectional view of the bumper, cloud stopper and fragment stopper elements of the first embodiment of the present invention and showing the layers thereof.
FIG. 4 is a perspective view of a second embodiment of the shield of the present invention showing the shield mounted on a spacecraft at hardpoint end structure portions thereof and showing a portion of the shield cut away to illustrate relative positioning of components thereof.
FIG. 5 is a cross-sectional view of the second embodiment of the shield of the present invention taken along lines 5--5 of FIG. 4 showing the component structures thereof.
FIG. 6 is a sectional view of the bumper, cloud stopper and fragment stopper elements of the second embodiment of the present invention showing the layers thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, the shield of the present invention is generally designated by the numeral 10. The shield 10 includes a bumper structure or element 12. The bumper element 12 is preferably generally an outer structure 12 so that it can provide protection from an initial or first impact with particles such as micrometeoroids and orbital debris, as may be encountered by a spacecraft in orbit. The shield 10 preferably also includes an intermediate structure or cloud stopper element 14. The cloud stopper element 14 is preferably positioned generally inward of or within the bumper element 12 so that it is located generally between the bumper element 12 and the spacecraft 18. The shield 10 additionally includes a fragment stopper element 16 or inner structure 16. The fragment stopper 16 is preferably positioned so that it is generally within the cloud stopper element 14 and generally between the cloud stopper element 14 and spacecraft 18. The bumper element 12, the cloud stopper 14 and fragment stopper 16 preferably generally enclose the spacecraft 18, as shown. In addition, the elements 12, 14 and 16 are each generally in the shape of a capsule generally closed at the ends thereof, as shown in FIG. 1.
The bumper element 12 preferably comprises a plurality of layers 20 of woven material composed of fine fabric. The bumper element layers 20 are preferably composed of a ceramic fabric material such as that sold under the trademark Nextel from the 3M Company or such as that sold under the trademark Astroquartz II. Such a woven material (or mesh or screen) is advantageous because it produces less secondary ejecta. There are preferably four ceramic fabric layers 20, although there may be more or less than this number, if desired. The fibrous ceramic layers 20 are preferably separated from each other in order to increase their effectiveness in stopping high velocity particles. The spacing of the layers 20 enables the impacting projectile to be melted or vaporized before striking the cloud stopper. At the same time, the secondary debris from the fabric bumper layers 20 consists of only fine fibers that impinge on underlying layers, and these fine fibers do not result in any significant damage to the underlying layers. For providing protection against a one-eighth inch diameter spherical aluminum particle, the spacing is preferably approximately one inch between outer surfaces of adjacent layers 20, as shown in FIG. 3. The layers 20 are preferably thin relative to the spacing between the adjacent layers 20, but the thickness of the layers 20 can vary according to the application and the size, velocity, etc. of the impacting particles from which protection is desired.
The Nextel or Astroquartz II layers 20 are preferably separated by bumper layer spacers 21 which provide the desired spacing between the layers 20. The bumper layer spacers 21 are preferably composed of aluminum, although other suitable materials may also be utilized, if desired.
The cloud stopper 14 is preferably composed of a layer of aluminum 22 positioned adjacent a layer of RTV silicone adhesive 24 which is positioned adjacent an inner layer of graphite epoxy 26. The aluminum layer 22 is the outermost layer and is preferably approximately 0.012 inches thick while the RTV layer is the intermediate layer and is preferably approximately 0.007 inches thick and the graphite epoxy layer is the innermost layer and is preferably approximately 0.033 inches thick. Thus, the layers 22, 24 and 26 are preferably bonded together so as to provide an integral cloud stopper sheet 14. The aluminum layer 22 composition is sufficiently penetration resistant to absorb the small fragments resulting from high velocity collisions with the bumper 12, while the graphite epoxy layer 26 is sufficiently strong to resist fracture and sufficiently stiff to preclude large deformations under the impulse load delivered by the impacting particle.
The fragment stopper 16 is preferably a single layer composed of a material (and of a thickness) that is sufficiently puncture-resistant to withstand collision with relatively low velocity particles on the order of one or two kilometers per second. Thus, the fragment stopper is preferably composed of a fibrous material which is capable of absorbing and containing the particles upon collision therewith. The fibrous material of the fragment stopper 16 is preferably a polyethylene yarn composition woven without resin such as that sold under the trademark Spectra 1000 from Allied Fibers, which is a division of Allied Corporation U.S.A or under the trade designation Dyneema SK60 from Dyneema V. of Holland. Alternatively, the fragment stopper 16 may also be composed of an aramid fiber material such as Kevlar trademark registered to E.I. dupont de Nemours, Inc.
The elements 12, 14 and 16 are preferably spaced from each other, as shown in FIG. 2. The spacing between the bumper 12 and the cloud stopper 14 is preferably provided by a spacer 28 which is preferably a set of spacers 28. The set of spacers 28 is preferably integral with the bumper layer spacers 21. The set of spacers 28 preferably relatively positions the bumper element 12 and cloud stopper element 14 so that the separation distance measured from the outer surface 30 of the bumper 12 to the outer surface 32 of the cloud stopper element 14 is preferably approximately four inches. Each of the set of spacers 28 is preferably positioned so that it is generally forty-five degrees from the other spacers and so that the spacers 28 are diametrically opposed to each other, as shown in FIG. 2. However, other suitable locations for the set of spacers 28 may be suitable, as well. The set of spacers 28 provides spacing between the bumper 12 and cloud stopper 14 sufficient to prevent critical damage to the cloud stopper 14 from ensuing after the bumper element 12 has been impacted by a high velocity particle.
Spacer 28 which is preferably a set of spacers 28 is also provided in order to attach the fragment stopper element 16 a selected distance from the inner surface of the cloud stopper 14. The set of spacers 28 preferably positions the cloud stopper 14 and fragment stopper element 16 so that outer surface 32 of the cloud stopper 14 is spaced approximately one inch from an outer surface 36 of the fragment stopper 16. However, other spacings between the cloud stopper 14 and fragment stopper 16 may also be used. The fragment stopper element 16 is preferably thin relative to the spacing between the cloud stopper 14 and the fragment stopper 16, but the thickness of the fragment stopper 16 can vary according to the application and the size, velocity, etc. of the impacting particles from which protection is desired. As shown in FIG. 2, the bumper element 12, the cloud stopper element 14 and fragment stopper element 16 are preferably generally octagonal in cross-section and concentric.
Since the spacecraft 18 may be composed of a very thin material incapable of sustaining impact loads or may be otherwise very sensitive to impact forces, the bumper element 12, cloud element 14 and fragment element 16 are preferably not mounted directly onto the main structures of the spacecraft 18 but rather mounted onto spacecraft structures more capable of sustaining impact forces. Consequently, the elements 12, 14 and 16 are preferably mounted onto hardpoint end portions 38 of the spacecraft 18 via mounts 40. These hardpoint portions 38 may include piping or other suitable spacecraft structures that may be less sensitive to impact loads than the spacecraft's main structure.
The set of spacers 28 (and the bumper layer spacers 21) are preferably simply eight beams extending longitudinally the entire length of the shield 10 and may be in the shape of I-beams. However, there may be more or less than this number of spacers 28 in the set of spacers 28, and the set of spacers 28 may also have other suitable shapes, if desired. In addition, the set of spacers 28 are preferably composed of aluminum for simplifying fabrication processes, etc. of the shield 10. However, carbon graphite composites or other suitable lightweight compositions may also be utilized, if desired. The set of spacers 28 are preferably generally thin and narrow because they function simply to provide spacing between the elements 12, 14 and 16.
FIGS. 4, 5 and 6 show a second embodiment 110 of the invention. Embodiment 110 is generally similar to embodiment 10, except that bumper element 112 (outer structure 112) is preferably composed of two sheets 120 of tin. Tin is utilized in the bumper element 112 because the tin composition melts the impacting projectile as well as the tin so that no tin fragments are produced except for molten tin drops which spray out at approximately a forty five degree angle from the point of impact. Thus, due to the utilization of tin, the impact forces are spread out over a relatively large area. As a result, the impact does not present a significant concentrated impulsive force load to the underlying structures 114 and 116. The tin of the bumper element 112 is preferably a high purity tin (of approximately 99.99% purity) which provides it with an extremely low melting point so that it has the ability to produce only molten or vaporized material from the impact.
In addition to the utilization of tin in the bumper 112, embodiment 110 is different from embodiment 10 in the composition of the cloud stopper 114. Cloud stopper 114 is preferably composed of an outer layer 122 of titanium, an intermediate layer of RTV adhesive 124 and an inner layer of graphite epoxy layer 126 bonded together into an integral unitary sheet. Except as described, cloud stopper element 114 and layers 122, 124 and 126 are identical to cloud stopper element 14 and layers 22, 24 and 26.
As with embodiment 10, embodiment 110 is not mounted on main structures of the spacecraft 118. Instead, the shield 110 is preferably mounted onto hardpoint end structures 138 of the spacecraft 118 via suitable mounts 140 in order to prevent or at least minimize transfer of impact forces to main structures of the spacecraft 118.
Embodiment 110 also includes a set of spacers 128. The set of spacers 128 preferably separate the outer surface 130 of the bumper 112 from the outer surface 132 of the cloud stopper element 114 a distance of preferably approximately four inches. The bumper layer spacers 121 preferably separate the two sheets 120 of tin from each other by a distance of approximately two inches. However, more than this number of sheets 120 of tin may be utilized and equally spaced, if desired. Bumper layer spacers 121 are preferably integral with the set of spacers 128. In addition, the set of spacers 128 preferably separate the outer surface 132 of the cloud stopper element 114 from the outer surface 136 of the fragment stopper element 116 a distance of preferably approximately one inch, as with embodiment 10. Alternatively, the spacing distance between the fragment stopper element 116 and cloud stopper element 114 may be reduced (or adjacent and in contact with each other) or increased in order to provide a desired degree of protection. If the spacing distance between elements 114 and 116 (as well as between elements 14 and 16) is reduced, the thickness of the fragment stopper element 114 (as well as element 14) must be increased in order to maintain the same degree of effectiveness in stopping impacting fragments. Except as described, the elements of embodiment 110 are identical to the elements of embodiment 10.
Although the embodiments 10 and 110 have been described as including elements 12 and 112, 14 and 114 and 16 and 116 which are generally octagonal in cross-sectional shape, other suitable shapes may also be utilized, if desired. For example, the elements 12, 14 and 16 may be oval, rectangular or triangular in cross-sectional shape.
Accordingly, there has been provided, in accordance with the invention, a spacecraft shield which is generally more effective in providing protection against a variety of impacting particles having a relatively wide range of velocities and which is also generally lightweight relative to the degree of protection provided. The spacecraft shield thus fully satisfies the objectives set forth above. It is to be understood that all the terms used herein are descriptive rather than limiting. Although the invention has been described in conjunction with the specific embodiments set forth above, many alternative embodiments, modifications and variations will be apparent to those skilled in the art in light of the disclosure set forth herein. Accordingly, it is intended to include all such alternatives, embodiments, modifications and variations that fall within the spirit and scope of the invention as set forth in the claims hereinbelow. | A shield for protecting spacecraft from impact with particles having a wide range of velocities includes three elements. Sets of spacers are used to secure the elements in positions in which they are separated from each other selected distances. The bumper element is the outermost element and is composed of ceramic fabric material or tin and is utilized to vaporize or melt a high velocity particle upon impact therewith. The intermediate element is a cloud stopper element and is composed of a metallic layer over a graphite epoxy layer and is used to absorb small fragments resulting from high velocity impacts with the bumper element. The innermost element is a fragment stopper element and is utilized to absorb low velocity particles. The shield elements generally enclose the spacecraft and are mounted onto hardpoint end portions of the spacecraft so that impact forces are not transmitted directly to impact sensitive portions of the spacecraft. The spacing of the elements generally prevents transmission of highly concentrated impact forces to successively inwardly positioned elements of the shield thereby preventing impact damage to the spacecraft. | 1 |
The present application is a U.S. National Phase Application pursuant to 35 U.S.C. §371 of International Application No. PCT/AU2011/000731 filed on Jun. 17, 2011, which claims priority to Australian Patent Application 2010902669, filed Jun. 18, 2010, the disclosures of which are incorporated herein by reference in their entirety.
TECHNICAL FIELD The present invention relates generally to underwater mining, and in particular relates to a tool for carrying out seafloor mining in cooperation with other seafloor tools.
BACKGROUND OF THE INVENTION
Seabed excavation is often performed by dredging, for example to retrieve valuable alluvial placer deposits or to keep waterways navigable. Suction dredging involves positioning a gathering end of a pipe or tube close to the seabed material to be excavated, and using a surface pump to generate a negative differential pressure to suck water and nearby mobile seafloor sediment up the pipe. Cutter suction dredging further provides a cutter head at or near the suction inlet to release compacted soils, gravels or even hard rock, to be sucked up the tube, Large cutter suction dredges can apply tens of thousands of kilowatts of cutting power. Other seabed dredging techniques include auger suction, jet lift, air lift and bucket dredging.
Most dredging equipment typically operates only to depths of tens of metres, with even very large dredges having maximum dredging depths of little more than one hundred metres. Dredging is thus usually limited to relatively shallow water.
Subsea boreholes such as oil wells can operate in deeper water of up to several thousand metres depth. However, subsea borehole mining technology does not enable seafloor mining.
Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior an base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
SUMMARY OF THE INVENTION
According to a first broad aspect the present invention provides a seafloor auxiliary mining tool for use in a seafloor mining system, the seafloor auxiliary mining tool comprising:
a seafloor locomotion system enabling traversal of the seafloor; umbilical connections for receiving power and control signals from a surface source; a boom mounted auxiliary cutting tool for cutting extremities of a seafloor deposit; and means for sizing cuttings produced by the auxiliary cutting tool to ensure such cuttings are no greater than a desired size.
According to a second aspect the present invention provides a method for seafloor auxiliary mining in a seafloor mining system, the method comprising:
a seafloor auxiliary mining tool traversing the seafloor using a seafloor locomotion system; the tool receiving power and control signals from a surface source via umbilical connections; a boom mounted auxiliary cutting tool cutting extremities of a seafloor deposit; and a sizing means of the tool sizing cuttings produced by the auxiliary cutting tool to ensure such cuttings are no greater than a desired size.
The means for sizing cuttings may comprise at least one pair of cutting heads which form the auxiliary cutting tool, the cutting heads being configured to preferentially draw cuttings between the pair of cutting heads, and the pair of cutting heads being spaced apart by a distance corresponding to the desired cutting size. In such embodiments, cuttings larger than the desired cutting size which are drawn between the pair of cutting heads will be further cut and/or crushed to be less than the desired cutting size. The spacing between the or each pair of cutting heads can be fixed at a predetermined spacing, for example depending on the ore being mined and the size of particles needing to be extracted. Alternatively, the spacing between the or each pair of cutting heads may in some embodiments be adjustable during mining operations. Alternatively, the means for sizing cuttings may comprise a sizing grill proximal to the auxiliary cutting tool, for example positioned above the cutting head between the head and the boom, and/or aft of the cutting head. Alternatively, the means for sizing cuttings may comprise other suitable sizing devices whether fixed or adjustable. The pair of cutting heads are preferably counter-rotating so as to draw cuttings between the cutting heads to effect sizing of the cuttings.
By providing the auxiliary mining tool with an auxiliary cutting tool, and leaving bulk mining for a separate seafloor tool, the present invention provides for a relatively agile seafloor cutting tool which has enhanced mobility enabling operation in seafloor regions of complex topography and which can flexibly perform an array of cutting tasks. The auxiliary cutting tool can thus be used in preparation for bulk mining to cut down peripheries of complex seafloor formations in order to present relatively flat and horizontal benches suitable for a separate bulk mining tool. The present invention thus provides an auxiliary tool operable to function in cooperation with other seafloor mining tools to effect retrieval of the seafloor material, even when presented with a complex seafloor topography, while able to function alone when presented with complex seafloor topography. At some sites the agility of the auxiliary mining tool may be such that other tools may not be required to effect retrieval of the seafloor material.
The seafloor auxiliary mining tool is capable of traversing uneven ground and slopes, such capability being affected by the seafloor locomotion system. The seafloor locomotion system may comprise any suitable locomotion elements, for example wheels, continuous tracks, legs, or the like. The locomotion system preferably enables the auxiliary mining tool to traverse seafloor terrain sloped up to about 10 degrees, more preferably up to about 20 degrees and even more preferably up to about 25 degrees.
The auxiliary mining tool in preferred embodiments is operable to work a seafloor site to prepare a bench for bulk mining. The auxiliary mining tool in preferred embodiments is further operable to work remnant edges left by a bulk miner. The boom for mounting the auxiliary cutting tool preferably comprises an hydraulically operated articulated arm. In one form, the boom may be mounted on an upper carriage assembly capable of slewing relative to the auxiliary mining tool centre line.
In some embodiments of the invention, the seafloor auxiliary mining tool may comprise a detachable winch cable attachment point, allowing the tool to be winched between the seafloor and the surface, and to detach from the winch cable and self-propel once on the seabed.
Further, the present invention provides a seafloor auxiliary mining tool adaptable in some embodiments to deployment at significant water depths. For example some embodiments may be operable at depths greater than about 400 m, more preferably greater than 1000 m and more preferably greater than 1500 m depth. Nevertheless it is to be appreciated that the auxiliary mining tool of the present invention may also present a useful seafloor mining option in water as shallow as about 100 m or other relatively shallow submerged applications. Accordingly it is to be appreciated that references to the seafloor or seabed are not intended to exclude application of the present invention to mining or excavation of lake floors, estuary floors, fjord floors, sound floors, bay floors, harbour floors or the like, whether in salt, brackish, or fresh water, and such applications are included within the scope of the present specification.
In embodiments of he invention deployed to seafloor sites of complex topography, the seafloor auxiliary mining tool is preferably employed to initiate site excavation. For example the seafloor auxiliary mining tool may prepare a landing area for other seafloor tools, and may excavate extremities of the site in order to prepare a first bench ready for bulk mining.
A preferred embodiment of the invention further includes a suction delivery line having an inlet adjacent to the auxiliary cutting tool and an outlet spaced from the auxiliary mining tool. In preferred embodiments of the invention, the auxiliary mining tool comprises a slurry pump system and a slurry inlet proximal to the cutting head(s), configured to capture cuttings in the form of a slurry. The slurry may be pumped a short distance from the seafloor auxiliary mining tool, for example simply to one side of the path taken or to be taken by the tool. Alternatively, the slurry may be pumped to a seafloor stockpile location some distance away from the seafloor auxiliary mining tool via a suitable transfer pipe. The slurry inlet, or suction inlet, may be positioned just all of the cutting head. In embodiments comprising two or more cutting heads, the or each suction inlet may be positioned between cutting heads.
In preferred embodiments, a collection shroud partially surrounds the cutting head(s) to optimise containment and collection of cuttings by the slurry pump system. The seafloor auxiliary mining tool preferably comprises a blade to help keep cuttings ahead of the vehicle, and also preferably configured to shroud the cutting tool by maintaining cuttings near the cutting head and assist reworking of oversized cuttings. The blade is preferably arcuately shaped so as to effect substantially equal shrouding at differing slew positions of the cutting tool. The blade preferably assists a suction inlet of the tool in clearing cuttings produced by the cutting heads. The blade is also preferably configured to clear the path ahead of the auxiliary mining tool by acting as a push blade as the machine traverses forwards.
The seafloor auxiliary mining tool may be an untethered remotely operated vehicle (ROV) or may be a tethered vehicle operated by umbilicals connecting to the surface.
The seafloor auxiliary mining tool preferably clears its own cuttings to the spaced outlet at a dump site to enable the seafloor auxiliary mining tool to progress through a formation as it works. For example the auxiliary mining tool may pump its cuttings in slurry form to a position lateral to the tool's path of travel.
The seafloor auxiliary mining tool's weight is preferably selected in order to apply the forces required for the auxiliary mining tasks. In order to further stabilise the auxiliary mining tool, movable anchoring spuds may be provided.
The bench may comprise an ore bench of valuable ore to be retrieved, or may comprise a bench of hard rock, or other seafloor material to be removed for other purposes. The ore may comprise seafloor massive sulphides.
In an alternative embodiment of the system, the auxiliary miner is configured with slurry transfer pipes which are arranged to deliver cuttings from the tool in a slurry form to a stockpile site distal from the cutting location of the tool.
BRIEF DESCRIPTION OF THE DRAWINGS
An example of the invention will now be described with reference to the accompanying drawings, in which:
FIG. 1 is a simplified overview of a subsea system incorporating an auxiliary mining tool in accordance with a preferred embodiment of the present invention;
FIG. 2 is a side view of an auxiliary mining tool in accordance with one embodiment of the present invention;
FIG. 3 illustrates the cutting and suction process of the auxiliary mining tool of FIG. 2 ;
FIG. 4 depicts the overall auxiliary mining tool system;
FIG. 5 is a perspective view of the boom-mounted cutting head of the auxiliary mining tool; and
FIG. 6 is a cross sectional view of the boom-mounted cutting head of the auxiliary mining tool in operation.
FIG. 7 a depicts the auxiliary mining tool performing site preparation;
FIG. 7 b depicts the auxiliary mining tool trimming remnant edges of an ore bench;
FIG. 8 depicts a further embodiment of the auxiliary mining tool with a moveable anchoring/stabilising spud system;
FIGS. 9 a - 9 d illustrate an auxiliary cutter in accordance with another embodiment of the invention; and FIGS. 10 a and 10 b illustrate an auxiliary cutter in accordance with a further embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a simplified overview of a subsea system 100 , which incorporates an auxiliary mining tool (AUX) 116 in accordance with an embodiment of the present invention. A derrick 102 and dewatering plant 104 are mounted upon an oceangoing production support vessel (PSV) 106 . The PSV 106 has ore transfer facilities to load retrieved ore onto barge 108 . The present embodiment provides a tool 116 operable to about 2500 m depth, however alternative embodiments may be designed for operation to about 3000 m depth or greater. During production operations, seafloor mining took (SMTs) will be used to excavate ore from the seabed 110 . The SMTs comprise a seafloor bulk miner 112 , a seafloor gathering machine (GM) 114 and a seafloor auxiliary mining machine 116 and a stockpiling system 124 . The bulk miner (BM) 112 and gatherer 114 may be of any suitable form. In this embodiment ore mined by the auxiliary mining machine 116 and hulk mining machine 112 is gathered and pumped by each respective machine in the form of a slurry to a stockpile system 124 , for example through stockpile transfer pipe 126 (shown interrupted in FIG. 1 for clarity).
The stockpiled ore is gathered and pumped, in the form of slurry, through a riser transfer pipe (RTP) 120 to a subsea lift pump 118 , which then lifts the slurry via a rigid riser 122 (shown interrupted in FIG. 1 , and may he up to about 2500 m long in this embodiment). The slurry travels to the surface support vessel 106 where it is dewatered by plant 104 . The waste water is returned under pressure back to the seafloor to provide charge pressure for the subsea lift pump 118 . The dewatered ore is offloaded onto transport barge 108 to be transported to a stockpile facility before being transported to a processing site.
The seafloor auxiliary mining tool 116 of this embodiment is provided for cutting and if/as required pumping material away from a work face location. The seafloor auxiliary mining tool 116 is a remote operated vehicle, capable of operating to a water depth of about 2500 m, and is operated from on board the PSV 106 . Operation of the seafloor auxiliary mining tool 116 is controlled subject to ore grade, over-all production rate and operational and maintenance constraints. Excavated particle size is controlled by the auxiliary mining tool 116 cutter type, cutter rotation speed, speed of advancement of the cutter heads, depth of cut, cutter pick spacing and angle and cutter head spacing.
Bulk mining and gathering can then be carried out by any suitable means.
While the auxiliary mining tool 116 may be utilised in any suitable mining process, in the embodiment shown in FIG. 1 the ore recovery sequence is as follows. First, any unconsolidated sediment is removed using the gathering machine (GM), and deposited in a pre defined area that may or may not form part of the mine. Then, obstructions are cut down using the AUX 116 of this embodiment, to prepare a level landing area for the BM 112 and GM 114 , This site preparation by the auxiliary mining machine 116 is illustrated in FIG. 7 a.
Next, ore left by the auxiliary mining tool 116 is gathered with the GM 114 . Benches are cut using the BM 112 then cut and sized ore is gathered using GM 114 , this being repeated until remnant edges are about 4 metres high. Then, the remnant edges are trimmed using the AUX 116 of this embodiment, as shown in FIG. 7 b.
Thus, the AUX 116 initiates seafloor mining operations and prepares an adequate landing area for other seafloor tools, and if required for other seafloor devices such as a stockpiling device. The AUX 116 is also used to remove edge sections of ore benches which cannot be accessed or efficiently mined by a bulk miner.
FIG. 2 is a side view of auxiliary mining tool 116 in accordance with this embodiment of the present invention. FIG. 2 illustrates the size of the AUX 116 of this embodiment, giving insight into its functionality. The AUX 116 pumps ore utilising a slurry dredge pump system 202 , to a seafloor stock pile area., which is then gathered at a later date by suitable seafloor gathering machine (GM) 114 . Continuous tracks 204 provide for seafloor locomotion of the tool 116 , even over complex seafloor topography. Winch cable attachment point 206 permits detachable attachment of the tool 116 to a winch cable to permit winching of the tool 116 between the surface and the seafloor. Cutting head 210 is mounted on boom 208 , permitting use of cutting head 210 in a versatile range of positions, heights, and angles.
FIG. 3 illustrates the cutting and suction process of the auxiliary mining tool 116 . As can be seen, the AUX 116 is a vehicle with tracks 204 and a cutter suction boom assembly 208 , which is articulated and capable of boom stewing of about +/−40 degrees laterally of the machine centre tine and is capable of rising above and below the machine. As seen in FIG. 5 , cutting head 210 comprises two pairs of counter rotating cutter heads 212 which are electrically or hydraulically driven via umbilical power supply to cut ore and deliver cuttings to an inlet in the form of a centrally located suction head 214 located in between the counter-rotating cutter heads 212 . Suction head 214 can be in various shapes and sizes to suit the size and type of material being cut and extracted. Shown in FIG. 2 , a bucket/blade 216 is also provided to assist with material clearing and add to the effectiveness of the cutters 212 . Bucket/blade 216 also acts as a shroud for the cutters to aid in the suction removal of the cuttings. A shroud 218 in FIG. 2 is also provided to assist in the effectiveness of the suction head 214 in FIG. 5 and size the cuttings and control the size of the cuttings.
Tool 116 may further comprise a water jet system (not shown) for high pressure water injection to the cutter head 210 , and a slurry / ore suction / delivery line, using a suction dredge pump system, to pump cut material and transport it to a subsea stock pile zone via a stockpile hose 126 of FIG. 1 and connector system, and stockpile system 124 . In another embodiment, an upper carriage assembly 220 in FIG. 2 provides the capability of slewing the auxiliary mining vehicle's cutting heads. In another embodiment a further assembly (hydraulic cylinder 222 ) on the cutter heads allows the spacing of the cutter heads to be adjusted during operation to improve cutting efficiency and cuttings extraction efficiency and size the cuttings and control the size of the cuttings.
In this embodiment the tool 116 has a dry land weight of approx 200 to 250 tonnes, a cutting power to tool weight ratio suitable for this type of machine, and a number of primary functions, The tool 116 removes obstructions and high points and prepares a clear landing area for other tools to commence cutting operations, as shown in FIG. 7 a . Tool 116 cuts and cleans areas of the bench that are inaccessible to a less agile bulk miner, as shown in FIG. 7 b . The tool 116 can pump cut material to a seafloor stockpile area, and assist with levelling and grinding up seafloor chimneys. The boom action of the tool 116 enables cutting of bench heights of up to about 4 m, even on a slope, and enables the tool 116 to clear bench edges and/or footwall interfaces which are not readily accessible by less agile seafloor tools.
The auxiliary mining tool 116 is further operable to perform tidying cuts to clean up the mine site at the completion of mining, and can also cut an access ramp for other seafloor tools to high points of a mine, and/or cut a ramp up to a peak area thus generating its own access way to the peak itself.
The tool 116 is manoeuvred on the seafloor by means of crawler tracks 204 . It is capable of handling rocky ground and rough terrain, and has an ability to both operate and manoeuvre on slopes. The tool 116 can also be lifted and landed to relocate around the site using its main winch wire 402 , from the support vessel.
The AUX 116 is designed to cut and gather ore, pumping it to either a stockpile or to a side cast zone just behind or beside the vehicle. The AUX 116 is designed with a counter rotating cutter head 210 complete with central suction head 214 to cut ore efficiently and if/as required deliver it to a stockpile at a spaced location.
The cutter/suction head 210 is mounted on an articulated boom 208 capable of slewing, lifting and lowering, and changing the angular position of the cutter suction head 210 in the vertical plane. The forward and aft spacing of the cutter heads can be changed by mechanism 222 to adjust and increase cutting and suction efficiency during operations and size the cuttings and control the size of the cuttings.
The overall Auxiliary Mining Machine system is outlined in FIG. 4 . The Production Support Vessel (PSV) hosts the control room from which the AUX 116 is operated, along with the winches for both the umbilical and the lift wire, and an A frame for deployment and recovery of the AUX 116 . The AUX is connected to the vessel by means of an umbilical cable 404 , and a main hoist wire 402 .
The umbilical cable 404 provides electrical power to drive the motors and pumps required to drive the main components of the AUX 116 , such as track drive motors, hydraulic system drive motor(s), dredge system pump drive motor(s) and the cutter drive system.
The umbilical 404 also provides control lines suitably in the form of multiplexed fibre optic communication links between the AUX 116 and the operational controls on the PSV 106 .
The AUX 116 is lowered from the PSV 106 to the seafloor, via the main hoist wire 402 . When the AUX 116 is landed out on the seafloor, the hoist wire 402 can be disconnected and recovered either back to the PSV 106 , or to a safe height whereby it will not get tangled with the umbilical 404 during mining operations.
The AUX 116 incorporates systems within the chassis to find, engage, secure and disconnect the stockpile hose connector (also incorporating a coupling, emergency disconnect system and swivel). If required, a stockpile hose may be stored within the AUX chassis on a stowage arrangement such as a wind-out reel. Once the AUX 116 is on the seafloor, a stockpile hose is connected (if required for stockpile mining operations) and the AUX 116 is then ready for cutting and stockpiling operations.
When the AUX 116 is ready to be recovered to the PSV 106 , the hoist wire 402 is reconnected and the stockpile hose disconnected. The cutter boom 208 is slewed to the zero degree, fully extended and lifted position. Tool 116 can then be lifted from the seafloor, and recovered to the PSV 106 .
As previously outlined, the AUX incorporates two different methods for ore placement, those being the vehicle rear or side-cast method, and the stockpile transfer method. As shown in FIG. 3 , control of suitable valves allows slurry from suction head 214 to be selectively directed to either a stockpile hose connector system 302 , or a rear/side cast lay down outlet 304 . The rear or sidecast method is utilised in areas that are easily, and efficiently accessed by the gathering machine 114 (for subsequent clean up and recovery of the material). The stockpile method is utilised for restricted access areas so as to transfer the ore to a pre-defined stockpile location from which the GM 114 will recover the ore. Appropriate mine planning can define which ore placement method will be adopted for which location.
A dual counter-rotating drum cutter 210 is used for the main cutting head which is outlined in general in FIGS. 5 and 6 . The cutter 210 is mounted on a two function hydraulic boom 208 which is capable of lifting and lowering in the horizontal axis, and slewing around the vertical axis. The boom 208 provides a versatile mounting for the cutter assembly 210 and allows a large volume of rock to be cut without moving the vehicle itself. This versatility allows the arm 208 and cutter 210 to ‘target’, for example, steps or other discontinuities, such as isolated towers, as may be encountered in the mine. The rock cutter head 210 is of about 600 kW power, on an articulated arm 208 , which provides a versatile mounting for the cutter and allows large volumes of rock to be cut without moving the auxiliary miner itself.
The boom 208 operates in successive downward/sideward cuts to complete a full sump depth, full width cut of the mine face to an approximate sumping depth around 1 metre. The boom and cutter angle positions can then be adjusted to carry out a further 1 metre sumping depth cut before the vehicle is required to reposition forward.
The excavated material can be drawn away from the work area, through the suction nozzle 214 detailed in FIGS. 5 and 6 , by a high flow dredge pump system. The slurry flow circuit is shown in more detail in FIG. 3 . A dilution system is used to reduce the chances of blockage and control the slurry density in the suction and delivery lines. A densitometer and flow meter is used to constantly monitor the concentration and velocity gradients through the slurry circuit.
The AUX 114 of the further embodiment is a tracked vehicle. Whilst mining, a moveable anchoring system taking the form of stabilising spuds engage and penetrate the seafloor surface layer in order to provide more positive control of the miner, as shown in FIGS. 7 a and 7 b . As further shown in FIG. 8 , each movable spud 802 of a vehicle anchoring/stabilising system is independently powered, allowing limited ability to level the vehicle on uneven ground. The spuds are designed to penetrate through any loose surface material to locate into good quality ground. For soft ground, larger area shoes can be fitted to the spuds. The spuds can also each be in the form of a blade. The blade then allows the functionality of a spud and also allows an ability to move material during forward or aft locomotion of the machine.
A jet water system 306 is installed to provide clearance of the suction grizzly 214 in the event of blockage, and agitation of the material face to be cut if required. The jet system 306 can clean the cutter head 210 or tracks 204 in the event of clogging. The jet system may also assist with slurry line blockage prevention/clearance.
The AUX 116 can move from one area of the seafloor to another in one of two ways. The AUX 116 is capable of tracking on seafloor topographies of less than about 10 degrees, at rates >about 600 m/hour. Alternatively, the vehicle 116 can be hoisted off the seafloor using the main hoist wire 402 , and manoeuvred to the next site.
When manoeuvring in the locality, the powerful track assemblies 204 provide for efficient repositioning of the vehicle 116 for maximum operational production capability. The AUX 116 thus provides more efficient cutting and stock-piling of excavated material.
FIGS. 9 a - 9 d illustrate an auxiliary cutter 900 in accordance with another embodiment of the invention, comprising a cutting tool support boom 902 , front swing-out stabilising legs 904 with vertical jacking, tracks 906 for site traversing, a rear sonar array 908 , electronic control pod indicated at 910 , a rear stabilising anchor/blade 912 , main cutting tools 914 , a crown cutter stockpile gathering system 916 mounted to the underside of boom 902 , two thrusters 918 , a lifting point and capture bowl 922 for 20 degree slope recovery, a stockpile hose interface 924 and a slurry transfer pump and motor 926 .
FIG. 10 illustrates a further embodiment of the invention in which an auxiliary miner 1000 has a blade 1010 to push cuttings ahead of the chassis and minimise or avoid cuttings passing beneath the tool 1000 . Blade 1010 is semicircularly curved so that the aft cutting heads remain at a substantially constant distance from the blade when moved azimuthally, as shown in FIG. 10 b . This arrangement effects improved efficiency of gathering by the suction inlet adjacent the cutting head, as visible in FIG. 10 b , and also clears stray cuttings from the path of the tool.
It is to be appreciated that particular terms used herein may he synonymous with other terms which equally describe the present invention and the scope of the present application is thus not to he limited to any one such synonym. For example, seafloor mining tools may also be referred to as subsea machines, a production support vessel may be referred to as a surface vessel and/or surface facilities, ore may be equally or alternatively referred to as rock, consolidated sediment, unconsolidated sediment, soil, seafloor material, and mining may comprise cutting, dredging or otherwise removing material. Moreover, particular values provided give an illustration of scale in the described embodiments but are not to be considered restrictive as to the scale or range of values which might be used in other embodiments to suit the environment of application.
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. | A seafloor auxiliary mining tool for use in a seafloor mining system. The seafloor auxiliary mining tool has a seafloor locomotion system enabling traversal of the seafloor. Umbilical connections receive power and control signals from a surface source. A boom mounted auxiliary cutting tool is configured to cut extremities of a seafloor deposit. Cuttings produced by the auxiliary cutting tool are sized by sizing means, to ensure such cuttings are no greater than a desired size. | 4 |
RELATED APPLICATION
This application concerns an alternative charging technique for valved cells as the term valved cell is defined in U.S. Pat. No. 4,817,388, entitled ENGINE WITH PRESSURIZED VALVED CELL.
FIELD OF THE INVENTION
This invention relates to an internal combustion engine having an auxiliary combustion chamber for augmented power and thermal efficiency and more broadly to an independently pressurized chamber for use with various types of heat engines.
BRIEF SUMMARY OF THE INVENTION
There is, therefore, provided in practice of this invention according to a presently preferred embodiment a method of operating an engine comprising the steps of compressing a gas to a pressure approximately the same as a pressure cyclically achieved in the engine, temporarily isolating a mass of the compressed gas, and opening communication between the isolated gas and the engine while the isolated gas is at approximately the same pressure as in the engine for intermittently releasing substantially all of the temporarily isolated mass of gas into the engine for expansion.
This method of operating can be performed in an internal combustion engine having a conventional positive-displacement expander with at least one valve for admitting a combustible mixture into the expander and exhausting combustion products therefrom. An auxiliary cell is connected to the expander by an exhaust or transfer valve, and to a source of externally-compressed gas, hereinafter referred to as source gas, by an intake valve.
During a cycle, an input valve to the cell is opened for introducing source gas to the cell, following which the intake valve is closed. Since the transfer valve is also closed at the same time, the cell is effectively charged with compressed gas, hereinafter referred to as cell gas. The input valve to the cell is closed before the beginning of the engine's expansion cycle.
During the compression cycle of the engine and the initial portion of the combustion process, the pressure of the combustible mixture in the expander, hereinafter referred to as expander gas, is increasing. At some point the pressure in the expander gas will momentarily equal the pressure of the cell gas. The transfer valve between the cell and the expander is opened at this point, communicating the cell gas with the expander gas. Ideally, all heat input and mixing of cell gas and expander gas now occurs at constant volume, following which continued expansion by the engine expander will reduce the pressure of the mixed gas, and the gas will begin to flow from the cell. By the end of the exhaust cycle of the engine, the transfer valve is closed and the cycle repeats.
This process, which is disclosed and claimed in U.S. Pat. No. 4,817,388, can be seen as useful for efficiently adding gases to an engine following compression and prior to and/or during expansion, and could thus be thought of as a kind of gaseous fluid injector, which in turn is useful for such things as augmenting the total amount of expandable fluid in the engine, returning otherwise-waste heat to the engine within the augmenting fluid, and adding gaseous and vaporized fuels to an engine. In addition, a novel two stroke engine can be constructed with essentially all of the power provided by the cell gas.
Regarding the specific nature of the invention disclosed herein, it is proposed that, as a means of efficiently charging the valved cell, the timing of the operation of the cell's intake and transfer valves be controlled, in the following manner:
Following the opening of the transfer valve, as expansion in the engine occurs, pressure will eventually begin to drop in the expander gas and a pressure difference between the cell and the expander is created, causing the cell gas to flow into the expander and the pressure in the cell to drop. As expansion continues, the pressure of the cell gas will eventually drop until it reaches the pressure of the source gas. Immediately, the cell intake valve is made to open, thus communicating the source gas with the cell gas. As expansion continues, flow from the cell creates a pressure differential between the cell gas and the source gas, causing the source gas to flow into the cell at the same time that the cell gas flows out. If the source gas were flowing from a large reservoir and the restrictions from manifolding into and out of the cell were minimal, a constant-pressure expansion process would be approximated, with source gas flowing into the cell replacing cell gas flowing into the expander. Eventually, the cell gas would completely replace the source gas, at which point the cell exhaust and intake valves are made to close.
The result of this unique process is the thermodynamically efficient charging of the cell with a fresh quantity of source gas.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the present invention will be appreciated as the same becomes better understood by reference to the following detailed description, when considered in connection with the accompanying drawings, wherein:
FIG. 1 is a semi-schematic cross-section of an internal combustion engine constructed according to principles of this invention at the end of its compression stroke;
FIG. 2 illustrates the engine of FIG. 1 as the source gas begins displacing the cell gas;
FIG. 3 is a semi-schematic cross-section of a novel internal combustion engine apparatus constructed according to principles of this invention at the end of its compression stroke;
FIG. 4 illustrates the engine of FIG. 3 as combustion proceeds;
FIG. 5 illustrates the engine of FIG. 3 as the source gas begins displacing the cell gas; and
FIG. 6 illustrates the engine of FIG. 3 just as the cell charging process has completed.
DETAILED DESCRIPTION
FIG. 1 illustrates largely schematically an internal combustion engine suitable for practice of this invention. Only one cylinder 10 and power piston 11 for such an engine is illustrated. It will be understood that this is merely representative of one of a plurality of such structures that make up such an engine. Other portions of the engine are conventional. Thus, the crankshaft, camshaft, etc., of the engine are not specifically illustrated, but instead, the mechanical interconnection to coordinate operation of the engine, transmit power, etc., are merely indicated by dashed lines.
Each cylinder in the engine has an intake valve 12 and an exhaust valve 13 illustrated in their closed positions. A spark plug for the cylinder is not indicated in the drawing and it will be understood that the internal combustion engine may operate on either an Otto or Diesel cycle. This description is in the context of a four-stroke Otto cycle.
Each cylinder of the engine has a cylindrical valved cell 14. For purposes of the schematic illustration, the valved cell is illustrated integral with the cylinder. All that is required is as short a fluid communication as possible between cell and cylinder. A transfer valve 15, shown in its open position in FIG. 1, interconnects the cell and cylinder. An input valve 16 interconnects the cell with a compressor 17. The compressor may, for example, be a conventional supercharger or turbocharger or other suitable gas compressing structure. The compressor is by preference multi-staged and intercooled. A single such compressor may be used for all of the valved cells of a multiple cylinder engine. A heat source may be placed between the compressor 17 and the valved cell 14. Rotary valves 15 and 16 are illustrated in this embodiment. Other types of valve structure may also be employed.
Two different stages of operation of the internal combustion engine are represented schematically in FIGS. 1 and 2.
FIG. 1 illustrates the engine with the power piston at or near top dead center. At about this time, the transfer valve is opened. Preferably, the transfer valve is opened when pressure in the cell and cylinder are approximately the same. This eases the opening force on the transfer valve. More importantly, it allows the expander gas and the cell gas to communicate without a pressure drop occurring between them, which is thermodynamically undesirable. The compressed gas in the cell in this embodiment is a combustible mixture of air and fuel. Fuel is introduced into the compressed air after the air leaves the compressor. A conventional fuel injection port (not shown) may be used.
Note that there is no limitation placed on the valved cell design regarding the pressures that are permissible within the valved cell. It is only necessary that the pressures on both sides of the transfer valve be approximately equal. Therefore, since almost any required pressure may be created on the engine side of the transfer valve, either by simple compression or combustion or some combination thereof, it is possible to envision that fuel may be injected into the valved cell and combustion may be made to take place prior to the moment of pressure equalization. Since the dimensions of the valved cell may easily be made fixed, the combustion at such a time may be made to occur under a condition of perfectly constant volume.
With the transfer valve open, combustion is initiated in the cylinder by a spark in the Otto cycle or by compression in the Diesel cycle. Combustion occurs in both the cylinder and the combustible mixture in the cell. Thus, the effective mass of combustible mixture is larger than it would be in the absence of the valved cell.
FIG. 2 illustrates the engine part way into the expansion stroke. At this point the pressures in the cylinder and the cell equal the pressure of the source gas for the cell. The cell intake valve has therfore been practically instantaneously opened, with little or no pressure drop occurring during the communication of the source gas with the cell gas, which is thermodynamically preferred. As constant-pressure expansion continues from this point, the cell gas is displaced from the cell by the source gas. When the cell gas has been completely displaced, the cell exhaust valve is closed practically instantaneously, followed by the closure of the intake valve.
The remaining portion of the expansion cycle, as well as the exhaust, intake and compression cycles, are all standard.
With such an embodiment, the cylinder and piston of the engine form an expander which does useful work as the hot, compressed gases expand. By using the valved cell containing a combustible mixture, the expander is presented with an additional charge of fuel and air for expansion which may be nearly isothermally compressed which is more efficient than the process occurring in the cylinder of the internal combustion engine. This amounts to a novel and more efficient type of "supercharging" process. Note that this type of supercharging may be used in conjunction with turbocharging. Also, note that this type of supercharging/turbocharging will not require a reduction of the engine's compression ratio, as is presently the case.
When the engine is operating at partial loads, the valved cell may not be used, the cell transfer valve may be held closed and the engine may operate in a conventional manner. Since the valved cell would essentially be on standby waiting for a demand for additional power from the engine, the throttle setting for the engine at a given cruising speed may be relatively high for high thermal efficiency resulting from the maximum compression ratio thus permitted at partial power output. Power variations may be obtained in this mode of operation by conventional means. However, when a full throttle acceleration is desired, for example, operation of the valved cell may be initiated. This, in effect, augments the power available from the engine by increasing its effective displacement. The added displacement is fed with more nearly isothermally compressed gas rather than gas compressed within a hot engine cylinder. As a result, this mode of supercharging enhances power while retaining better thermal efficiency.
In addition, with such an embodiment it is possible that otherwise-waste heat will be absorbed from the interior of the cell sufficient to obviate the need for additional external cooling of the cell. Also, if the density of the cell gas is greater than the density, following compression, of the expander gas, the net density of the expandable fluids in the engine will have been increased, resulting in an increased ability of the expandable fluids to transform heat into a pressure increase. Finally, different fuel:air mixture ratios may be used in the cell and cylinder as appropriate for efficient combustion and expansion, avoidance of burning of the transfer valve, and the like.
FIGS. 3 thru 6 illustrate largely schematically four different stages of operation of a novel approach to constructing a valved cell which is charged by valve timing. Only one cylinder 110 and power piston 111 for such an engine is illustrated. It will be understood that, as in FIGS. 1 and 2, this is merely representative of one of a plurality of such structures that make up such an engine.
Each cylinder in the engine has an intake valve 112 and an exhaust valve 113 illustrated in their closed positions. A spark plug for the cylinder is not indicated in the drawing and it will be understood that the internal combustion engine may operate on either an Otto or Diesel cycle that is, increasing the molecular activity of the contained compressed gas by adding heat internally as the result of the combustion of fuel, said fuel being added in this instance by a fuel injector 121. This description is in the context of a four-stroke Otto cycle.
Each cylinder of the engine has a cylindrical valved cell 114. For purposes of the schematic illustration, the valved cell is illustrated integral with the cylinder. All that is required is as short a fluid communication as possible between cell and cylinder.
The valved cell includes a piston 118. In this embodiment, the piston is moved and held in place hydraulically by the addition of hydraulic fluid to a hydraulic cylinder 119 through an inlet/exhaust port 128. The hydraulic fluid allows the displacer piston to be adjusted and then fixed in position, thereby allowing the internal volume of the cell to be increased or reduced as desired.
A transfer valve 115, shown in its closed position in FIG. 1, interconnects the cell and cylinder. An cell input valve 116 interconnects the cell with a compressor 117.
Between the cell input valve 116 and the cell compressed gas inlet 135 is a throttle valve 120, which is located in immediate proximity to the cell input valve. A high-pressure fuel injector 121 allows fuel to be injected directly into the cell.
Cell intake valve 116 is lubricated by a variable-flow, high-pressure oiler 124, and transfer valve 115 is lubricated by a variable-flow, high-pressure oiler 125.
Finally, part or all of the compressed gas from the compressor 117 is used to cool the area of the transfer valve by entering port 126 and exhausting port 127 before entering port 135. Following compression by the external compressor 117, the heat source 136 may be used to add heat to the compressed gas.
Four different stages of operation of the internal combustion engine are represented schematically in FIGS. 3 thru 6.
FIG. 3 illustrates the engine with the power piston at or near Top Dead Center. At about Top Dead Center, the transfer valve 115 is made to open. Preferably, the transfer valve is opened when pressure in the cell and cylinder are approximately the same. This allows the expander gas and the cell gas to communicate without a pressure drop occurring between them, which is thermodynamically undesirable.
The transfer valve is basically a lightweight poppet valve with upper and lower valve faces allowing it to "seal" in two directions. In this instance the transfer valve will be shown to open and close largely as a result of pressure differences which cyclically occur across the valve seat and across the valve stem. Note that the compressed gas which communicates with the top of the transfer valve stem through gas inlet 126 flows out gas outlet 127 and into gas inlet 135, which is the inlet through which the cell is charged. Thus, the gas which "charges" the cell through gas inlet 135 is at approximately the same pressure as the gas which communicates with the top of the transfer valve.
Regarding the action of the transfer valve, the transfer valve, when first charged, is held closed against the lower valve seat by the pressure difference across the valve seat, since the expander side of the transfer valve is experiencing the relatively low-pressure processes of exhaust, intake and compression. However, at the end of the compression stroke and in some instances following the initiation of combustion on the expander side of the transfer valve, the pressures on either side of the valve head become approximately equal. Any further pressure increase should thus amount to a pressure difference building across the valve stem, and the valve should begin to open. Any subsequent rise in pressure in the cylinder will then also raise the pressure in the cell, and as the pressure in the cylinder and cell increase a pressure difference is created across the transfer valve stem, effectively forcing the transfer valve to quickly and completely open.
In FIG. 4, we see that the transfer valve has opened completely. Note that the transfer valve has sealed against its upper valve seat, serving to isolate the transfer valve stem from any continuing pressure increase within the cell and cylinder, as would occur with internal combustion of fuel.
In FIG. 5, the power piston 111 has expanded to the point where the gas pressure in the cylinder and the cell equal the pressure of the source gas flowing from the compressor 117. This is the preferred moment to open the intake valve, since it would allow the cell gas and the source gas to communicate without a pressure drop occurring between them, which is thermodynamically preferable.
Regarding the action of the cell intake valve 116, it is basically a lightweight, flow-actuated, one-way poppet valve, the stem of which is hollow and ported to allow gas flow through the stem. In operation the state of pressure equalization on both sides of intake valve 116 moves valve 116 off its seat. As a result, intake valve 116 opens readily with no appreciable pressure drop in the process, coming to rest against the stop 131.
In FIG. 6, the power piston has expanded a sufficient amount to have nearly filled the cell with source gas. This source gas has been required to flow through a throttle valve 120, resulting in a slight decrease in pressure below that of the source gas. Therefore, the gas which communicates with the top of the transfer valve through ports 126 and 127 is seen to be at a higher pressure than the gas within the cell. As a result a pressure difference is created across the transfer valve 115 valve stem, causing it to close. Flow into the cell ceases and begins to reverse as a result of surge, thus automatically closing the flow-sensitive intake valve 116. Finally, at some optimum point fuel is injected into the cell with fuel injector 121, which upon combustion will increase the molecular activity of the contained, compressed gas by heat input, and the cell is thus recharged.
It should further be noted that heat input may be accomplished by means other than combustion, such as, for example, conductive heating by an atomic pile, or radiative heating by solar energy.
Although limited embodiments of valved cell engines have been described and illustrated herein, many modifications and variations will be apparent to one skilled in the art. The specific mechanical arrangements of such engines are subject to a broad variety of implementations based on the schematic illustrations provided herein. Variations of the operations may be provided as well. For example, timing of the various valve movements might be controlled, as by computer, taking into account power output, rpm, source gas pressure and the like. Or the valves may operate solely as a result of the inherent creation of pressure differentials and without benefit of mechanical or electromechanical activation, trading off some thermodynamic losses from late valve opening and closing in order to achieve a simple cell construction.
Many other modifications and variations will be apparent to one skilled in the art and it is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | An internal combustion engine of the gasoline-burning variety has an essentially constant maximum displacement or volume. This requires compromises in design to achieve acceptable power output at full throttle and reasonable thermal efficiency at cruising power. It would be desirable to have an engine with differing displacements for those operating conditions. However, the mechanical constraints of a conventional engine do not easily permit of that possibility. It is also desirable to separate the process of generating expandable fluid for an engine and the expansion of such fluid. This permits each of the two processes to be more closely optimized. Compression of fluid can be more nearly isothermal, and expansion which approaches truly isentropic expansion may be provided. It would also be desirable to capture waste heat from the combustion products within the expandable fluid for enhancing thermal efficiency of an engine. It has been found possible to charge a cell or chamber with an expandable fluid in such a way that said fluid may be efficiently presented without appreciable pressure fluxuation to an accompanying cyclical expander. It has also been found possible to use such a cell or chamber as a means of creating a true constant-volume heat input process. | 5 |
TECHNICAL FIELD
This invention relates generally to face seal assemblies comprised of a rotating seal rotor and a stationary face seal for sealing along the rotating shaft of a gas turbine engine, and in particular, to an improved ceramic seal rotor or composite seal rotor having a metal portion and a ceramic portion.
BACKGROUND OF THE INVENTION
Face seal assemblies are employed in gas turbine engines to prevent leakage of fluid along the engine's rotating shaft where the shaft extends through a wall or partition. These assemblies are comprised of a rotating component called a seal rotor and a non-rotating component called a face seal. The face seal is usually lightly spring loaded against the seal rotor.
Historically, various materials have been used for both the seal rotor and the face seal. For example, metals, carbon, ceramics, and other materials are mentioned in Zobens, U.S. Pat. No. 4,174,844, Floyd et al., U.S. Pat. No. 4,036,505, Fenerty et al., U.S. Pat. No. 3,926,443, and Stahl, U.S. Pat. No. 3,770,181. A common configuration is to have a metallic seal rotor and a carbon face seal. A problem with these seals is that oil coking results from the friction between the seal rotor and the face seal. Also, the carbon face seal tends to wear which requires that the engine be removed from service regularly to either inspect or replace the seal.
It is well known by those skilled in the art, that a carbon face seal will wear at a lower rate when rubbing against a ceramic surface as opposed to a metallic surface. Accordingly, one proposal for increasing the life of a conventional face seal assembly is to replace the metallic seal rotor with a ceramic seal rotor, (see for example Fenerty et al., teaching a seal assembly for a water pump in which one of the seal rings is ceramic, column 1, lines 50-55). However, such technology is not applicable to gas turbine engines because the rotating components in these engines are assembled in a lockup. This means that the rotating components, (the compressor disks and turbine disks including the seal rotors) are first stacked one atop the other and then forced, and held together by a large compressive force. This compressive force produces concentrated tensile stresses on the sealing surfaces of the seal rotors abutting a rotating component. Because of its brittle nature conventional ceramic seal rotors tend to crack under this compressive force.
Accordingly, a need still exists for a face seal assembly, for a gas turbine engine, having a seal rotor that can withstand the compressive force of a lockup assembly and also provides a ceramic surface for sealingly engaging a carbon face seal.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a face seal assembly for a gas turbine engine, comprising a carbon face seal and a seal rotor that has a ceramic surface for sealingly engaging the carbon face seal, and a base portion that can withstand the compressive forces of a lockup assembly.
In a first embodiment, the present invention achieves the above-stated object by providing a face seal assembly that has a ceramic rotor seal and a spring member for reducing the compressive force transmitted to the base of the seal rotor. In a second embodiment, the seal assembly includes a composite seal rotor. The composite seal rotor has an inner metal ring, for transmitting compressive forces, and an outer ceramic ring for sealingly engaging the carbon face seal.
These and other objects, features and advantages of the present invention, are specifically set forth in, or will become apparent from, the following detailed description of a preferred embodiment of the invention when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a portion of a gas turbine engine having a conventional face seal assembly.
FIG. 2 is a cross-sectional view of a face seal assembly having the ceramic seal rotor contemplated by the present invention.
FIG. 3 is a cross-sectional view of a face seal assembly having the composite seal rotor contemplated by the present invention.
FIG. 4 is a cross-sectional view of an alternate embodiment of the composite seal rotor of FIG. 3.
FIG. 5 is a cross-sectional view of another alternate embodiment of the composite seal rotor of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 shows a compressor section of a gas turbine engine generally denoted by the reference numeral 10. The section 10 has a rotating compressor disk 12 coupled to a rotating shaft 14. Circumscribing the shaft 14 is a stationary housing 16. The housing 16 is mounted atop a bearing 18 having an inner race 19 which is mounted on the shaft 14. A metallic seal rotor 20 is mounted for rotation on the shaft 14 and has a base portion that abuts at one axial end with the inner race 19 and at the other axial end with the compressor disk 12. A portion of the housing 16 circumscribes a portion of the compressor disk 12 defining a leakage path, (referenced by arrow 21) therebetween. Mounted within the housing 16 is a nonrotating carbon face seal 22 that is positioned to abut an upper portion of the seal rotor 20 sealing the leakage path 21. A spring 26 forces the face seal 22 into sealing engagement with the upper portion of the rotor seal 20. Because of the lockup assembly of the engine containing the compressor section 10, a compressive force, represented by arrow F, of about 30,000 lbs, is transmitted from the compressor disk 12, through the base portion of the seal rotor 20, to the inner race 19.
In one embodiment of the present invention, shown in FIG. 2, a single piece, seal rotor 30 is made of a ring of ceramic material such as silicon carbide. The base portion of the seal rotor 30 is mounted and held between the inner race 19 and the compressor disk 12 so as to maintain a gap 36 between the seal rotor 30 and the shaft 14 and to place an axial face portion 38 into sealing engagement with the carbon face seal 22. The gap 36 permits the shaft 14 to thermally expand without coming into contact with the rotor seal 30. A spring 34 is mounted on the shaft 14 and is preferably disposed between the compressor disk 12 and the base of the seal rotor 30 so as to reduce the compressive force F transmitted to the seal 30. Alternately, the spring 34 can be disposed anywhere upstream of the seal 30 so long as it is in the load path of the compressive force F. Importantly, the backside 32 of the seal rotor 30 is configured for maximum surface area and hence maximum heat transfer. Also, it is preferable that the backside 32 receives cooling oil splashed from the interior of the bearing 18.
FIG. 3, depicts a composite rotor seal 40 which includes a metal ring 42 and a ceramic ring 46 made, for example, from silicon carbide. The metal ring 42 is press fit between the compressor shaft 12 and the inner race 19, and has a lip 44 circumscribing its outer surface at an axial end adjacent the inner race 19. The ceramic ring 46 sealingly abuts the carbon seal 22 and also has a lip 48 circumscribing its inner surface at an axial end opposite the lip 44. A metal cylindrical member 50 is disposed between the metal ring 42 and the ceramic ring 46 so that a portion of its inner surface is welded or brazed to the lip 44 and a portion of its outer surface is welded or brazed to the lip 48, thereby sealing the leakage path 21. Alternatively, the member 50 is interference fit between the rings 42 and 46.
In an alternative embodiment, see FIG. 4, a composite rotor seal 40a includes a metal ring 42a and a ceramic ring 46a. The metal ring 42a is mounted for rotation on the shaft 14 and axially clamped between the compressor shaft 12 and the inner race 19. The ring 42a has a lip 44a circumscribing its outer surface at an axial end adjacent the compressor shaft 12. The ceramic ring 46a has a first axial face portion 47a which sealingly engages the carbon seal 22 and a second axial face portion 49a for abutting an axial surface of the inner race 19 and thereby correctly positioning the ring 46a. The ring 46a also has a lip 48a circumscribing its inner surface at an axial end opposite the lip 44a. The lips 44a and 48a are configured so that when the ceramic ring 46a is mounted about the metal ring 42a an annular chamber 52a is defined therebetween. An annular, piloting spring 54a is disposed within the chamber 52a to keep the relative position of the rings 42a and 46a fixed and to maintain a gap 36a that allows for the thermal expansion of the metal ring 42a. Alternatively, as shown in FIG. 5, an elastomeric, piloting ring 54b can be used in place of piloting spring 54a.
Importantly, in each of these embodiments the ceramic ring 46,46a is not exposed to the compressive force generated by the lockup assembly, and the metal ring 42,42a does not contact the carbon seal 22.
Thus, a face seal assembly for a gas turbine engine, comprising a carbon face seal and a seal rotor is provided. The seal rotor has a ceramic surface for sealingly engaging the carbon face seal, and a base portion that can withstand the compressive forces of a lockup assembly.
Various modifications and alterations to the above described rotor seal will be apparent to those skilled in the art. Accordingly, the foregoing detailed description of the preferred embodiment of the invention should be considered exemplary in nature and not a limiting to the scope and spirit of the invention as set forth in the following claims. | A composite seal rotor is provided for sealing between the rotating components of a gas turbine engine held together by the compressive force of a lockup assembly and a housing circumscribing the rotating components and having carbon face seals mounted thereto. The seal rotor is comprised of a metal base portion disposed between two of said rotating components for transmitting said compressive force therethrough, and a ceramic surface for sealingly engaging said carbon face seal. | 5 |
TECHNICAL FIELD
[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and a device for transmitting data in a wireless communication system supporting a space division multiple access type down link communication.
BACKGROUND
[0002] The next generation mobile communication and wireless communication systems require improved data transmission rates and system capacities in the multiple cell environments. In response to such demands, studies on a Multi-Input Multi-Output (MIMO) system transmitting data using a plurality of antennas have been conducted, and a closed loop type MIMO system, using channel state information to improve the data transmission rates in the multiple cell environments, enhances a transmission performance using the channel state information.
[0003] Generally, in the MIMO system, a mobile station can recognize information on a receiving channel using received data, whereas a base station cannot recognize the channel state information. Accordingly, the base station has to know the channel state information to improve a performance of the system using the channel state information.
[0004] The system using the closed loop MIMO transmits data using information on a transmitting channel of the mobile station serviced by the base station. At this time, the base station cannot recognize the information on the transmitting channel of the mobile station serviced thereby and therefore, the information on the channel, including a Channel Quality Indicator (CQI) and a Pre-coding Matrix Index (PMI), is fed back to the base station from the mobile station.
[0005] The mobile station estimates the channel through which data is received, using signals received from the base station. The mobile station calculates the CQI using the estimated channel in order to apply a Modulation Coding Scheme (MCS) suitable for the channel situation when the base station transmits data. Furthermore, channel coefficients most suitable for the channel situation, namely, a pre-coding vector of a code book is selected from the known code book by using the estimated channel and the code book. The channel state information which the mobile station obtains using the estimated channel is transmitted through a feedback channel between the base station and the mobile station. The base station transmits data to the mobile station using the channel information transmitted from the mobile station, the selected MCS, and the pre-coding vector of the code book.
[0006] A number of studies on the closed loop MIMO system have been currently conducted, and the closed loop MIMO is employed for the multiple cell environments as well as the single cell environment. However, more studies on the method for reducing effects by interference from other cells in the multiple cell environments are required.
[0007] In particular, a mobile station at an edge of a cell receives weak signals from a base station to which it belongs and thus, a base station of an adjacent cell receives interference due to a mobile station belonging to the adjacent cell. Accordingly, a performance of the mobile station located at the edge of the cell is degraded by such interference between the cells.
[0008] Furthermore, sub-cells configuring multiple cells in the multiple cell environments are allocated the same cell identifier (e.g., a Physical Cell ID (PCID)) irrespective of the number of transmitting antennas. If the cells are densely arranged on account of an increase in the amount of used data in such a situation, the interference between the cells is increased so that network geometry is decreased, and the performance is deteriorated due to overhead according to handover between the cells.
SUMMARY
[0009] Accordingly, an aspect of the present disclosure is to provide a method and a device for transmitting data in a wireless communication system.
[0010] Furthermore, another aspect of the present disclosure is to provide a method and a device for efficiently transmitting data from a base station of a wireless communication system including virtual transmission ports to a mobile station.
[0011] In accordance with one aspect of the present disclosure, a method of transmitting data in a wireless communication system supporting multiple cells configured with a plurality of sub-cells is provided. The method includes: connecting at least one virtual transmission port respectively to the plurality of sub-cells; determining a transmission mode for a mobile station based on channel states between at least two sub-cells of the plurality of sub-cells and the mobile station; and transmitting, to the mobile station, data according to the sub-cells through the at least one virtual transmission port connected with the corresponding sub-cell based on the determined transmission mode.
[0012] In accordance with another aspect of the present disclosure, a base station for transmitting data in a wireless communication system supporting multiple cells configured with a plurality of sub-cells is provided. The base station includes: a transmitting unit that is provided with a plurality of antennas and transmits data according to the sub-cells through a wireless network; and a controller that connects at least one virtual transmission port respectively to the plurality of sub-cells, determines a transmission mode for a mobile station based on channel states between at least two sub-cells of the plurality of sub-cells and the mobile station, and transmits, to the mobile station, data according to the sub-cells through the at least one virtual transmission port connected with the corresponding sub-cell based on the determined transmission mode.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other aspects, features, and advantages of the present disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0014] FIG. 1 is a block diagram illustrating a device for transmitting data in a wireless communication system according to an embodiment of the present disclosure;
[0015] FIG. 2 illustrates an example in which two sub-cells transmit data to one mobile station;
[0016] FIG. 3 illustrates an example of a case where reception signal intensities and virtual transmission ports of sub-cells are configured in a situation in which a mobile station and the sub-cells are arranged; and
[0017] FIG. 4 is a flowchart illustrating a method of transmitting data in a wireless communication system according to an embodiment of the present disclosure.
DETAILED DESCRIPTION
[0018] A detailed description of known functions and configurations incorporated herein will be omitted as it may make the subject matter of the present disclosure rather unclear. Hereinafter, embodiments of the present disclosure will be specifically described with reference to the accompanying drawings.
[0019] A main subject matter of the present disclosure is to efficiently transmit data to a mobile station from a base station of a wireless communication system including virtual transmission ports.
[0020] Hereinafter, a method and a device for transmitting data to the mobile station from the base station of the wireless communication system according to an embodiment of the present disclosure will be described.
[0021] FIG. 1 is a block diagram illustrating a device for transmitting data in a wireless communication system according to an embodiment of the present disclosure.
[0022] The data transmitting device according to the embodiment of the present disclosure includes a scheduler 110 , a digital unit 130 , and an antenna unit 150 . The digital unit 130 includes a pre-coding unit 131 and a virtual transmission port generating block 133 .
[0023] Here, the embodiment of the present disclosure operates in the wireless communication system in which the virtual transmission ports and sub-cells are connected with each other. Accordingly, an operation of connecting the virtual transmission ports and the sub-cells in the wireless communication system will be described below. At this time, the operation of connecting the virtual transmission ports and the sub-cells is performed by the digital unit 130 as follows.
[0024] Further, it will be obvious to those skilled in the art to which the present disclosure pertains that the data transmitting device may be implemented with a transmitting unit and a controller. In this case, the controller may control the operation of connecting the virtual transmission ports and the sub-cells according to the embodiment of the present disclosure.
[0025] In a case where a plurality of sub-cells use the same cell ID, all the sub-cells have to know the same control channel and Down Link (DL) reference signal information for channel estimation so as to share scheduling information. Reference signals may be configured to be different or identical for the respective sub-cells.
[0026] The virtual transmission ports mix signals such that the sub-cells may share the control channel and the reference signal. For example, assuming a Common Reference Signal (CRS) system in which reference signals are differently transmitted for respective antennas in a 4Tx system based on the Long Term Evolution (LTE) rel.9, signals obtained by mixing CRS 0, 1, 2, and 3 are transmitted to the virtual transmission ports.
[0027] To this end, the virtual transmission port generating unit 130 uses a method of multiplying modem port (i.e., CRS port) outputs of the existing system by a specific matrix to generate the signals transmitted to the virtual transmission ports. At this time, the used matrix should satisfy a condition that all output signals exiting from the respective CRS ports are mixed at the same output level.
[0028] Signals of CRS ports 0 to n which have been pre-coded by the pre-coding unit 131 are distributed between virtual transmission ports 0 to m included in the virtual transmission port generating unit 133 at the same output level. Signals transmitted from virtual transmission ports 0 to m are transmitted to the antenna unit 150 .
[0029] The reference signal is a signal for channel estimation and thus, a sum of reference signals which a mobile station receives from several sub-cells should be the same as a value of the existing system which does not use the virtual transmission ports.
[0030] Hereinafter, a virtual transmission port is referred to as Vport. The matrix by which the CRS port signals are multiplied for generation of the signals to be transmitted to Vports has to satisfy the following condition. First, the CRS port signals have to be mixed at the same weight. In addition, the CRS port signals have to be mixed such that control channel signals are equally transmitted. For example, when control channels are divided and transmitted for respective antennas through Space-Frequency Block Coded (SFBC) in the 4Tx system, 2Tx cells have to be able to receive the same control channels.
[0031] When being multiplied by the matrix (hereinafter, referred to as a common matrix) for generation of the signals to be transmitted to Vports, the CRS port signals are mixed, with data traffic to be transmitted to respective Vports also multiplied by the matrix. Accordingly, in order that the desired data traffic is to be transmitted to respective final Vports, the data traffic is first multiplied by a separate matrix. Such a separate matrix (hereinafter, referred to as a pre-coding matrix) is selected such that the data traffic input to the CRS ports may be distinguished by the mobile station when the separate matrix is multiplied by the common matrix. Namely, the pre-coding matrix is configured such that data may be distinguished, and the mobile station is informed of the pre-coding value used in such a way.
[0032] The virtual transmission port generating unit 130 connects the generated virtual transmission ports to the respective sub-cells. At this time, virtual transmission ports of the 4Tx system are output as four Vports. Each sub-cell 5 of 2Tx is connected to two Vports. The Vport connecting method may be divided into two methods as follows.
[0033] First, a method of connecting four Vports to two sub-cells of 2TX in a one-to-one correspondence may be used. When there are two sub-cells of sub-cell #1 and sub-cell #2, the sub-cell #1 and the sub-cell #2 may be connected to Vport pairs {0, 1} and {2, 3}, or Vport pairs {0, 2} and {1, 3}, respectively. A constraint on the connection of the sub-cell to Vport is subject to whether there is a pre-coding matrix allowing the mobile station to differentiate data traffic transmitted to respective Vports. Namely, in a case where there is no pre-coding matrix which the mobile station may be informed of when a connection is to be made to Vport pairs {0, 3} and {1, 2}, the connection cannot be made. Such a connection method has an advantage in that the two sub-cells use mutually different pre-coding matrices so that space division multiple access can be made for the two sub-cells.
[0034] Second, a method of mutually connecting one of four Vports to sub-cells may be used. For example, when Vport #1 is used in common, the sub-cells may be connected to one of Vport pairs {0, 1}, {0, 2} and {0, 3}. Likewise to the first method, the connection of the sub-cells to Vport may be constrained according to the pre-coding matrix. Such a connection method has an advantage in that the sub-cells share one Vport so that cooperative transmission between the sub-cells is made easier. The cooperative transmission between the sub-cells can be made up to two times depending on the number of 4Tx cells capable of sharing one cell ID.
[0035] In the case of the method of mutually connecting one Vport to the sub-cells, Vport matching between the sub-cells may be used as reuse 3 . Assuming that there are 6 sub-cells using the same cell ID, in the first method, 3 sub-cells have the same Vport pair as reuse 2 . For example, 3 sub-cells are connected to Vport {0, 1} and the remaining 3 sub-cells are connected to Vport pair {2, 3}. In the case of using one Vport in common, 2 sub-cells may be connected to Vport pair {0, 1}, 2 sub-cells may be connected to Vport pair {0, 2}, and 2 sub-cells may be connected to Vport pair {0, 3}.
[0036] If the sub-cells using the same cell ID are connected to the same Vport, the same pre-coding matrix is used and thus, the mobile station may not distinguish data. Accordingly, the scheduler 110 has to configure a space division transmission mode through spatial division between the sub-cells using the same Vport, and the transmission mode configuring method for reuse of Vport between the sub-cells is as follows.
[0037] The sub-cells connected to Vport may not be able to receive correct signals due to a collision of data traffic between the sub-cells according to the Vport connection configuration. For example, if two sub-cells are connected to Vport {0, 1} of mutually different modems using the same cell ID, respectively, the same pre-coding matrix is used and thus, channel estimation fails, even though different data traffic is transmitted.
[0038] FIG. 2 illustrates an example in which two sub-cells transmit data to one mobile station.
[0039] Assuming that {right arrow over (h 0 )} and {right arrow over (h 1 )} denote channels transmitted from two sub-cells to a mobile station, respectively, and {right arrow over (m)} denotes a pre-coding matrix, only the signal from the desired sub-cell may be distinguished by Equation 1 below when mutually different Vport pairs are used.
[0000]
y
→
=
h
→
0
m
→
0
x
0
+
h
→
1
m
→
1
x
1
+
n
→
x
^
0
=
(
(
h
→
0
+
h
→
1
)
m
→
0
)
H
(
h
→
0
m
→
0
x
0
+
h
→
1
m
→
1
x
1
+
n
→
)
=
RxP
0
x
0
+
(
(
h
→
0
+
h
→
1
)
m
→
0
)
H
n
→
.
Equation
1
[0040] However, when the same Vport pair is used, an undistinguishable signal element remains as represented by Equation 2 below to cause data pollution.
[0000]
y
→
=
h
→
0
m
→
0
x
0
+
h
→
1
m
→
0
x
1
+
n
→
x
^
0
=
(
(
h
→
0
+
h
→
1
)
m
→
0
)
H
(
h
→
0
m
→
0
x
0
+
h
→
1
m
→
0
x
1
+
n
→
)
=
RxP
0
x
0
+
RxP
1
x
1
+
(
(
h
→
0
+
h
→
1
)
m
→
0
)
H
n
→
Equation
2
[0041] Accordingly, in this case, a difference between signal intensities from the two sub-cells for the mobile station has to be maintained such that the undistinguishable signal is received with a signal intensity which is not decoded (i.e., unavailable).
[0042] A sub-cell transmission mode is classified into a Multi-Input Multi-Output/Single-Input Multiple Output (MIMO/SIMO) transmission mode, a cooperative transmission mode, and a general transmission mode according to a Vport configuration such as a case of differently using Vports between sub-cells and a case of sharing one Vport.
[0043] The mode classification is configured according to an intensity of signals received from the sub-cells by the mobile station and therefore, the mode is classified for each mobile station. Thus, the mode classifying method is configured by the intensity of the signals between the mobile station and the sub-cells and the Vport configuration of the sub-cells.
[0044] A) In the case of differently using Vports between the sub-cells, namely, in the case of dividing 4Tx into Vport {0, 1} and Vport {2, 3}, the sub-cell transmission mode is classified into the cooperative transmission mode and the general transmission mode. The cooperative transmission mode is configured in a case in which a difference between signal intensities from sub-cells having the same Vport pair is not larger than a predetermined threshold value so that data pollution occurs due to the undesired signal in Equation 2. As an example, a case will be described in which reception signal intensities and Vports of sub-cells are configured in a situation where a mobile station and the sub-cells are arranged as illustrated in FIG. 3 . That is, when a difference between an intensity P A of a signal which the mobile station receives from a serving sub-cell A and an intensity P B of a signal which the mobile station receives from a neighboring sub-cell B having the same Vport pair satisfies Equation 3 below, the corresponding mobile station is configured in the cooperative transmission mode.
[0000] P A − P B ≦ P th Equation 3
[0045] Here, P th denotes a threshold value of a signal intensity difference causing the data pollution. When one or more neighboring sub-cells having the same Vport pair as that of the serving sub-cell among sub-cells using the same cell ID satisfy Equation 3, the mobile station serves as a cooperative transmission mode mobile station. Furthermore, all the sub-cells satisfying Equation 3 other than the serving sub-cell serve as cooperative transmission sub-cells of the corresponding mobile station. The cooperative transmission mode mobile station has to be scheduled such that all the cooperative transmission sub-cells transmit the same signal to the corresponding mobile station in the same frequency region during the scheduling. In this case, both SIMO and MIMO transmission can be made for 2Tx stream. That is, either one data stream or two data streams can be transmitted.
[0046] For a mobile station that does not satisfy the cooperative transmission mode condition, both SIMO and MIMO transmission can be made between the sub-cells having the same Vport pair according to a channel state without any constraint. In a case where the cooperative transmission mode mobile station and the non-cooperative transmission mode mobile station simultaneously require the same frequency resource, the non-cooperative transmission mode mobile station is allocated to the sub-cells or the cooperative transmission mode mobile station is allocated to the cooperative transmission sub-cells according to a predetermined scheduling matrix.
[0047] B) In the case of sharing Vport, namely, in the case of dividing 4Tx into Vport pairs {0, 1}, {0, 2}, and {0, 3}, the sub-cell transmission mode is classified into the MIMO/SIMO transmission mode, the cooperative transmission mode, and the general transmission mode. In this case, all the sub-cells share Vport 0 and therefore, if one or more of the sub-cells using the same cell ID satisfy Equation 3 irrespective of the Vport pair, data pollution may occur for data traffic transmitted to Vport 0. However, even through the data pollution occurs for Vport 0, space division multiple transmission can be made between the sub-cells through the SIMO transmission in a case in which the other Vport is different.
[0048] When a difference between an intensity PA of a signal which the mobile station receives from a serving sub-cell A and an intensity PB of a signal which the mobile station receives from a neighboring sub-cell B having the same Vport pair satisfies Equation 4 below, the mobile station is configured in the MIMO transmission mode. At this time, all neighboring sub-cells having the same cell ID and the same Vport pair have to satisfy Equation 4.
[0000] P A −Max( P B )> P _mimo_ th Equation 4
[0049] P_mimo_th is a value larger than a threshold value of a signal intensity difference by which the data pollution occurs. The mobile station in the MIMO transmission mode can perform both SIMO and MIMO transmission for 2Tx stream if necessary.
[0050] The mobile station which does not satisfy Equation 4 is configured in the SIMO transmission mode, and transmission for the corresponding mobile station is performed using unshared Vport.
[0051] In the configuration of sharing Vport, the cooperative transmission mode may be performed in the following two cases.
[0052] First, the mobile station having the same Vport pair satisfying Equation 3 is configured in the cooperative transmission mode. In this case, the corresponding mobile station has to unconditionally perform transmission in the cooperative transmission mode, and has to be scheduled such that all the cooperative transmission sub-cells transmit the same signal to the corresponding mobile station in the same frequency region during the scheduling.
[0053] In the case of not satisfying Equation 3, cooperative transmission can be made using a shared Vport. In this case, the mobile station may receive cooperative transmission from the sub-cells sharing the same cell ID if necessary.
[0054] The scheduler 110 schedules data for the mobile station based on the configured transmission mode of the mobile station. The scheduler 110 may use a distributed system for exchanging information for each of the sub-cells and a centralized system for performing scheduling by one common scheduler, and perform coordinated scheduling using information between the sub-cells.
[0055] The scheduling performed by the scheduler 110 according to the transmission mode of the mobile station and the virtual transmission port configuration has the following limitations.
[0056] A) In a case in which the mobile station in the cooperative transmission mode is first selected, the scheduling is performed such that all the cooperative transmission sub-cells transmit the same signal for resources required for the corresponding mobile station.
[0057] B) In a case in which the mobile station configured in the SIMO transmission mode is first selected, transmission is limited to be made through 1 stream even in the state where all of 2 streams are available according to the channel state and a request of the mobile station. At this time, the Vport used for transmission serves as an unshared Vport.
[0058] C) In a case in which the mobile station configured in the MIMO transmission mode is first selected, transmission can be made through 2 streams or 1 stream according to the channel state and a request of the mobile station.
[0059] D) In a case in which the mobile station that is not in the cooperative transmission mode is first selected, frequency resources may be allocated in such a manner to allow data traffics of different mobile stations according to sub-cells to be transmitted through the same frequency between sub-cells having the same cell ID. However, this is allowed only in sub-cells which are not cooperative transmission sub-cells for a first selected cooperative transmission mode mobile station.
[0060] FIG. 4 is a flowchart illustrating a method of transmitting data in a wireless communication system according to an embodiment of the present disclosure. Since the operations of the present disclosure performed in the respective devices have been described above in detail, detailed description thereof will be omitted in the following description.
[0061] Referring to FIG. 4 , a virtual transmission port generating unit 130 connects virtual transmission ports with respective sub-cells in step 401 . At this time, the virtual transmission port generating unit 130 connects different virtual transmission ports to the respective sub-cells, or mutually connects one of a plurality of virtual transmission ports to the respective sub-cells. Namely, the respective sub-cells may be connected to mutually different virtual transmission ports or the same virtual transmission port. The wireless communication system transmits data as in steps 403 to 407 .
[0062] In step 403 , a scheduler 110 configures a transmission mode of a mobile station contained in the sub-cells in view of an intensity of signals between the mobile station and the sub-cells and the connection configuration of the virtual transmission ports and the sub-cells. Here, the transmission mode of the mobile station includes at least one of a MIMO/SIMO transmission mode, a cooperative transmission mode, and a general mode.
[0063] In step 405 , the scheduler 110 schedules data for the mobile station based on the configured transmission mode of the mobile station.
[0064] In step 407 , a digital unit 130 performs pre-coding for the scheduled data and transmits the pre-coded data to an antenna unit 150 through the virtual transmission ports, and the antenna unit 150 transmits the pre-coded data to a receiver (not illustrated).
[0065] Although the embodiment has been described in the detailed description of the present disclosure, the present disclosure may be modified in various forms without departing from the scope of the present disclosure. Thus, the scope of the present disclosure shall not be determined merely based on the described exemplary embodiments and rather determined based on the accompanying claims and the equivalents thereto. | The present invention relates to a method and apparatus for transmitting data in a wireless communication system for supporting multi-cells formed of a plurality of sub-cells. The method includes the steps of: connecting at least one virtual transmission port to each of the plurality of sub-cells; determining the transmission mode for a terminal on the basis of channel states between at least two of the plurality of sub-cells and the terminal; and transmitting data for each sub-cell to the terminal through at least one virtual transmission port connected to a corresponding sub-cell on the basis of the determined transmission mode. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a scroll type compressor having a pair of scroll type compression units mounted in a single casing and also to a refrigeration cycle incorporating such a scroll type compressor.
2. Description of the Related Art
A refrigeration cycle has been proposed which includes a plurality of compressors encased in independent casings, with the compressors being selectively operated such that one, two or more of these compressors operate simultaneously to enable control of refrigeration power in accordance with a change in the refrigeration demand. It has also been proposed to use combinations of at least one compressor having a large compression power and at least one compressor having a small compression power, so as to enable a delicate control of the refrigeration power over a wider range. A promblem arises in the use of a plurality of compressors in various combinations with regard to sufficient lubrication of the compressors. This problem is serious particularly when the independent compressors have their own lubricating oil reservoirs in their casings. Namely, in such a case, lubricating oil tends to be shifted from one compressor to another compressor during running of the refrigeration cycle, so as to cause a shortage of oil in one compressor while the other is charged with excessive oil. Various specific measures have to be taken to maintain optimum oil levels in all the compressors for a long time.
In order to overcome this problem, it has been proposed to incorporate a plurality of compression units in a single casing having a lubricating oil reservoir which is common to all these compression units.
This type of compressor having a plurality of compression units having a common oil reservoir formed in a single casing, however, suffers from a disadvantage that alteration of the capacity of the compressor essentially requires alteration of constructions and specifications of the compressor units encased in the single casing. Since different types of compression units are employed, as well as differing combinations of these compression units, enormous cost is incurred not only in the production and service but also in administration of the component parts.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a scroll type compressor of the type having a plurality of compression units encased in a single or common casing, facilitates production, service and administration of component parts, while facilitating change of total capacity of the compressor, thus adapting the compressor to a variety of demands.
Another object of the present invention is to provide a refrigeration cycle incorporating such a scroll type compressor.
To this end, according to the present invention, there is provided a scroll type compressor having a pair of scroll type compression units which are encased in the same casing so as to provide a common lubricating oil reservoir in the casing, wherein the compression units have compression elements, drive shafts, driving motors and other components which are of the same constructions and specifications, and wherein each of the compression units are adapted to be selectively driven selectively by commercial electrical power or through a frequency-variable inverter so as to operate at different speeds.
In the scroll type compressor of the invention, a pair of compression units are encased in the same casing and are lubricated by a lubricating oil supplied from a common lubricating oil reservoir provided in the casing. Thus, equal lubricating conditions are preserved for both compression mechanisms without requiring any specific means. In addition, both compression units can be made up from the same components such as the compression elements, drive shafts, driving motors and so forth, because these components of both compression mechanisms are of the same constructions and specifications. This remarkably reduces loads in the production and administration, greatly contributing to a reduction in labor and cost, while reducing any mounting error which may occur when compression units of different specifications are used. For the same reason, errors are avoided in connecting the compressor to a refrigeration cycle or to electrical power supply. Furthermore, since each of the compression units can operate at various speeds either directly by commercial electrical power or through a frequency-variable inverter, the total capacity of the compressor can be widely varied by suitably selecting the combination of the operating speeds of both compression units.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of an embodiment of the scroll type compressor in accordance with the present invention;
FIG. 2 is an enlarged sectional view of one of compression units incorporated in the compressor shown in FIG. 1;
FIG. 3 is a schematic enlarged sectional view of the compression unit shown in FIG. 2, showing particularly an arrangement around a suction port;
FIG. 4 is a diagram showing the construction of an embodiment of the refrigeration cycle of the present invention, using the compressor in accordance with the invention;
FIG. 5 is a diagram of a modification of injection piping portion of the refrigeration cycle shown in FIG. 4;
FIG. 6 is a diagram showing the construction of another embodiment of the refrigeration cycle of the present invention, using the compressor in accordance with the invention; and
FIGS. 7 to 10 are power supply connection diagrams showing different patterns of use of the compressor of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, the compressor 1 has a hermetic casing 2 encasing a pair of compression units 3 which are disposed horizontally and coaxially such that their driving motors are disposed in opposition to each other.
Each compression unit 3 has a scroll type compression element 4, drive shaft 5, a frame 6 supporting the drive shaft 5 and a driving electric motor 7.
One of the compression units 3 will be specifically described because both units have identical construction and specifications.
The scroll type compression element 4 includes a revolving scroll 8 and a stationary scroll 9. The revolving scroll 8 has a base plate 10 and a spiral wrap 11 protruding perpendicularly from the base plate 10. The base plate 10 is provided at its rear side with an revolving bearing 12. An Oldham's ring 13 for preventing the revolving scroll from rotating about its own axis is provided on the back side of the base plate 10 of the revolving scroll 9. A pressure equalizing port 16 is formed to penetrate the base plate 10 so as to provide a communication between a compression chamber 14 which is formed between the revolving scroll and the stationary scroll and a back-pressure chamber 15 which is formed on the back side of the revolving scroll 8. The back-pressure chamber 15 is defined by the base plate 10 of the revolving scroll and the frame 6.
The stationary scroll 9 has a base plate 17 and a spiral wrap 18 perpendicularly projecting from the base plate 17. The base plate 17 is provided at its center with a discharge port 19 and at its peripheral portion with a suction port 20. The base plate 17 is also provided with an injection port 21 through which liquid refrigerant is injected into the compression chamber 14.
The drive shaft 5 is supported by a frame 6 and is provided at its one end with an eccentric shaft 22. The drive shaft 5 also has a central bore which forms an oil supply bore 23 opening in the end surface of the eccentric shaft 22. The oil supply bore 23 opens in the peripheral surface of the shaft 5 through an oil suction hole 24. A balance weight 25 is attached to the drive shaft 5.
The frame 6 carries a motor-side bearing 26 and a scroll-side bearing 27 for supporting the drive shafts. The motor-side bearing 26 has a spiral groove formed in the inner surface thereof. The spiral groove functions as a viscosity pump for suctioning oil into the motor-side bearing 26. When the scroll-side bearing 27 is a roller bearing as in the illustrated case, a bearing serving as a seal is provided between the scroll-side bearing 27 and the motor-side bearing 26. The frame 6 is provided with an oil suction conduit 28 through which the oil in an oil reservoir 29 formed in the bottom of the hermetic casing 2 is suctioned to the oil suction hole 24 in the drive shaft 5.
The driving electric motor 7 is composed of a stator 30 and a rotor 31.
The revolving scroll 8 and the stationary scroll 9 are assembled together such that their wraps mesh each other. The stationary scroll 9 is fixed to the frame 6 by bolts 32. The stationary scroll and the frame, as a unit, are fastened to a seat 34 formed on the inner wall of the hermetic casing 2, by bolts 33 which penetrate the stationary scroll 9 and the frame 6.
The eccentric shaft 22 of the drive shaft 5 is received in the revolving bearing 12. The end of the drive shaft 5 opposite to the eccentric shaft 22 is connected to the rotor 31 of the electric motor 7. The stator 30 of the electric motor 7 is fastened to the frame 6 by means of bolts 35.
A groove, formed in upper region of the zone around the stationary scroll 9 and the frame 6, provides a gas passage 36 through which refrigerant gas, discharged from the discharge port 19, is introduced to the space around the electric motor, while a groove, formed in a lower region of the above-mentioned zone, provides an oil level balancing groove 37 which serves to equalize the oil levels in the sections of the oil reservoir 29 which are adjacent to the stationary scroll 9 and to the electric motor 7. Grooves corresponding to the gas passage 36 and the balancing groove 37 are formed in the seat 34.
A spring 38 and a valve 39 are mounted in the suction port 20 in the stationary scroll 9. A suction pipe 40, penetrating the wall of the hermetic casing 2, is fitted into the suction port 20 through a seal ring 41. The end of the suction pipe 40 provides a valve seat on which the valve 39 is seated and pressed by the force of the spring 38, thus forming a check valve.
From a practical point of view, it is difficult to fit the suction pipe 40 in the suction port 20 of the stationary scroll 9 in a completely coaxial manner. In many cases, therefore, the suction pipe 40 is slightly inclined with respect to the axis of the suction port 20. In this embodiment, therefore, a specific design consideration is given to enable the valve 39 to incline within the suction port 20 by an angle greater than the angle of inclination of the suction pipe 40. More specifically, referring to FIG. 3, the gap g 1 between the suction port 20 and the valve 39, axial length l 1 of the valve 39, the gap g 2 between the suction port 20 and the suction pipe 40 and the length l 2 of the suction pipe 40 inside the suction port 20 are determined to meet the following condition:
g.sub.1 /l.sub.1 >g.sub.2 /l.sub.2
According to this arrangement, any slight inclination of the valve seat presented by the end surface of the suction pipe 40, caused by a slight inclination of the suction pipe 40 with respect to the axis of the suction port 20, can be well followed by inclination of the valve 39, so that the valve 30 can be seated on the valve seat in close contact therewith, thus providing a reliable checking function.
An injection pipe 43, penetrating the wall of the hermetic casing 2, is inserted into the injection port 21 through a seal ring 42 placed therebetween.
A discharge hole 44 and a power supply connection terminal base 45 for electrical connection to the respective electric motors are provided on the central barrel portion of the hermetic casing 2.
A rotation of the electric motor 7 causes a revolving motion of the revolving scroll 8 with respect to the stationary revolving scroll 9, due to the eccentric rotation of the eccentric shaft 22 of the drive shaft 5. The Oldham's ring 13 prevents the revolving scroll 8 from rotating about its own axis. This causes a compression chamber, formed between both scrolls, to be progressively moved towards the center while reducing its volume, so that refrigerant gas, suctioned through the suction pipe 40 via the suction port 20, is compressed and discharged from the discharge port 19. The discharged compressed refrigerant gas is introduced to the region around the electric motor through the gas passage 36 so as to cool the electric motor and is then delivered to the outside of the compressor through the discharge hole 44. During the operation of the compressor, the pressure of the refrigerant gas in the compression chamber 14 in its compression phase is introduced through the pressure equalizing port 16 into the back pressure chamber 15 so as to press the revolving scroll 8 onto the stationary scroll 9 with a moderate force.
When the operation of the compression unit is suspended, the valve 39 is pressed onto the valve seat on the end surface of the suction pipe 40 by the force of the spring 38, so as to prevent a reverse gas flow from the high-pressure side to the low-pressure side.
When the temperature of the discharged compressed gas becomes excessively high during the operation of the compression unit, refrigerant in liquid phase is injected from the injection pipe 43 into the compression chamber 14. Injection of the liquid refrigerant into the compression chamber is not conducted when the compression unit is stopped, since the pressure in the compression chamber is instantaneously elevated to the level of the discharge pressure when the operation of the compression unit is stopped.
The oil in the oil reservoir 29 formed in the bottom of the hermetic casing 2 is suction through the oil suctioned pipe 28, oil suctioned hole 24 and then through the oil supply bore 23 by the pressure differential between the interior of the hermetic casing 2 and the back pressure chamber 15, so as to be supplied to the scroll-side bearing 27 and the revolving bearing 12. The oil is then discharged into the back-pressure chamber 15. Meanwhile, part of the oil suctioned through the oil suction pipe 28 is supplied to the motor-side bearing 26 by a viscosity pump provided in the motor-side bearing 26.
The oil discharged into the back pressure chamber 15 is introduced through the pressure equalizing port 16 into the compression chamber 14 and is discharged together with the compressed gas through the discharge port 19. The oil is then separated from the compressed gas within the hermetic casing 2 and is returned to the oil reservoir 29.
In the described embodiment of the compressor, each of the compression units are adapted to be driven directly by commercial electric power or through an inverter. It is therefore possible to operate the compressor in one of the following three patterns, namely, a first pattern in which both compression units 3 are driven through inverters, a second pattern in which one of the compression units 3 is driven through the inverter while the other is driven directly by the commercial electric power, and a third pattern in which both compression units 3 are directly driven by the commercial electric power. The compression unit driven through the inverter can linearly change its speed in accordance with the frequency given by the inverter. Thus, the capacity of the compression unit is linearly changeable. In the second and third patterns and described above, one of the compression units driven by the commercial electric power may be controlled in an on-off manner. In the first pattern, one of the compression units may be on-off controlled. Thus, the capacity of the compressor of the described embodiment is variable over a wide range, without requiring compression units of different specifications.
Since two compression units are of the same constructions and specifications, there is no risk of mounting of these units in wrong manner. Furthermore, since only one type of compression unit is required, production efficiency is improved and troublesome work for administration of parts can be dispensed with.
The refrigeration cycle shown in FIG. 4 has, in addition to the compressor 1, components such as a condenser 46, a thermal receiver 47, an expansion valve 48, an evaporator 49 and an accumulator 50 which are connected through a discharge pipe 51, liquid pipe 52 and a suction pipe 53. The injection pipe 43 of the compressor 1 is connected to the thermal receiver 47 through an injection line 54.
A discharge pressure sensor 57 and a discharge gas temperature sensor 58 are attached to the discharge pipe 51. Likewise, a suction pressure sensor 59 and a suction gas temperature sensor 60 are attached to the suction pipe 53. An air temperature sensor 61 for sensing temperature of air blown into a room is disposed in the vicinity of the evaporator 49. A stop valve 55 is provided in the injection line 54 branched into two pipes, with each pipe including a check valve 56. The stop valve 55 is controlled so as to open and close in accordance with a signal from the discharge gas temperature sensor 58. Although an on-off type valve such as a solenoid-actuated valve may be used as the stop valve 55, a better effect is obtained by using a valve which changes its opening degree in accordance with the temperature of the discharged gas sensed by the discharge gas temperature sensor 58.
In the described embodiment of the compressor of the present invention, the interior of the hermetic casing 2 is maintained at the same pressure level as the discharge pressure, and the check valve 39 for preventing reverse flow of the compressed refrigerant gas during stopping of the compressor is provided in the suction side of the scroll compression element of each compression unit. In the described embodiment, therefore, only one stop valve 55, disposed in the common portion of the injection line 54, is used in order to prevent injection of liquid refrigerant into the compression units. However, when the compression mechanism is of the type in which the check valve for preventing reverse flow of the compressed gas is provided in the discharge side of the scroll type compression element of each compression unit, e.g., in the discharge port 19, it is preferred to provide a stop valve 55 in each branched injection line leading to each compression unit of the compressor as shown in FIG. 5, in order to prevent liquid refrigerant from coming into the compression unit which is not operating.
The refrigeration cycle shown in FIG. 4 is suitable for use in a refrigeration system or an air-conditioner exclusively used for cooling air.
The refrigeration cycle shown in FIG. 6 differs from that shown in FIG. 4 in that the condenser 46 and the evaporator 47 are respectively substituted by an outdoor heat exchanger 62 and an indoor heat exchanger 63 each of which can operate both as a condenser and an evaporator, and a four-way valve 64 and associated piping are added to enable switching of path of flow of the refrigerant, thus forming a heat pump cycle which can operate either in a cooling mode or a heating mode.
A description will now be given of an embodiment of the invention in which the compressor of the invention is effectively used in the refrigeration cycle of the type shown in FIG. 4 or of the type shown in FIG. 6. The refrigeration cycle is not described because it is identical to that shown in FIG. 4 or 6.
FIG. 7 shows the operation pattern in which both of two compression units of the compressor 1 are driven by commercial electric power. In this mode, the electric motors of both compression units are supplied with commercial electric power through relays 66, 67. One of the electric motors in-off controlled by a controller 68 in accordance with a signal from the temperature sensor 61 or 65. In this case, it is preferred that the on-off signal from the controller 68 is switched between the relays 69 and 70 so that both compression units are alternatingly put to the on-off control, whereby excessive burdening of one of the compression units is avoided.
FIG. 9 shows the operation pattern in which both compression units are driven through inverters. In this case, the driving electric motors are supplied with electric power through inverters 71 and 72 which are controlled and turned on and off by a controller 75. On-off operation of either one of the compression units may also be adopted in this mode, depending on the capacity demand of the refrigeration cycle. In such a case, as in the pattern described before, the relays 66 and 67 are arranged switchably so as to enable that both compression units are alternatingly put to on-off operation, thus equalizing the total working hours of both compression units. It is also possible to provide circuits which directly connect the electric motors to the commercial power source and which are provided with relays 73, 74, so that both compression units can be operated by the commercial electric power in the event of a failure in the inverters.
FIG. 10 shows the operation patterns in which one of the compression units is driven by the commercial electric power while the other is driven through the inverter. As illustrated, the inverter 71 is put into effect. The controller 75 controls the frequency of the inverter output power in accordance with the refrigeration load. If the total capacity of the compressor 1 is too large for the demanded refrigeration load even after lowering of the inverter output frequency to the minimum level, the electric motor directly connected to the commercial electric power supply is turned off. In this operation pattern, the compression unit operated through the inverter operates longer than the compression mechanism driven by the commercial electric power. It is therefore preferred that these compression units are replaced with each other at a suitable period.
In the event of a failure in the inverter, both compression units are driven by the commercial electric power through the inverter-bypassing circuits.
In the event that a problem develops in one of the compression units, the other compression unit is driven through the inverter or by the commercial electric power.
The above-described change-over of modes are attained without difficulty by selective operation of the relays 66, 67, 73, 76, 77 and 78 as shown in FIG. 10.
Obviously, according to the present invention, it is possible to drive one of the compression units through an inverter or directly by commercial electric power while the other is experiencing problems or possibly provide operation patterns in which both compression units are driven by the commercial power directly or through inverters.
Thus, according to the invention, each of two compression units can be driven directly by the commercial electric power or indirectly through inverter, so that the compressor can operate in any one of the aforesaid three operation patterns. This enables a delicate control of the capacity over a wide range, adapting to a variety of refrigeration demands.
As stated before, in the compressor of the invention having two compression units encased in a common casing so as to make a common use of an oil reservoir, one of the compression units may be stopped while the other is operating. In such a case, there is a risk that the refrigerant gas leaks from the compression unit which is stopped, causing various inconveniences on the operation of the refrigeration cycle. A risk also exists that oil undesirably fills the compression chamber of the compression unit which is not operating. In order to eliminate such risks, it is very important that the check valve 39 in the suction port 20 of each compression unit is closed without fail. Thus, the arrangement explained before in connection with FIG. 3, which ensures that the check valve 39 is seated on the valve seat in close contact therewith.
In the embodiment shown in FIG. 1, the hermetic casing 2 is formed by welding a pair of cup-shaped casing parts to the central barrel portion as at 2' and 2', and the discharge port 44 and the power supply connection terminal base 45 are provided on the central barrel portion. Thus, the advantage brought about by the use of the same design and specifications, explained before in connection with the compression units, is attained also with the case of production of the hermetic casing 2, thus contributing to a further improvement in the production efficiency and reduction in the cost.
As will be understood from the foregoing description, the present invention offers the following advantages.
Firstly, it is to be noted that production, service and parts administration are simplified and facilitated to reduce costs and, at the same time, erroneous mounting is avoided, by virtue of the fact that two compression units encased in the same compressor casing have the same construction and specifications.
Secondly, the compressor of the invention can cope with various refrigeration demands over a wide range since three operation patterns are available by virtue of the fact that each of the compression units can operate either directly by commercial electrical power or through an inverter.
Thirdly, since both compression units make a common use of an oil reservoir formed in the common casing, there is no need of specific consideration which has been hitherto necessary to maintain optimum lubricating oil levels in independent compressors. | A scroll type compressor having a pair of scroll type compression units which are encased in the same casing so as to make a common use of a lubricating oil reservoir provided in the casing, wherein the compression units have compression elements, drive shafts, driving motors and other components which are of the same constructions and specifications, and wherein each of the compression units are adapted to be driven selectively by commercial electrical power or through a frequency-variable inverter so as to operate at different speeds. Since both compression units can be made up from the same components such as the compression elements, loads in the production, service and administration, are greatly reduced contributing to a reduction in the labor and cost, while eliminating any mounting error. Various operation patterns are obtainable by selecting the combination of the direct commercial power and the power supplied through the inverters, so as to provide delicate control of refrigeration capacity over a wide range in accordance with the level of the load demand. Common use of the lubricating oil reservoir by both compression units eliminates necessity for specific measure for preserving oil levels equally for both compression units. | 5 |
RELATED APPLICATION
[0001] This is a divisional application of the co-pending application bearing Ser. No. 10/893024 filed on Jul. 15, 2004 which is a divisional of application bearing Ser. No. 10/224218 filed on Aug. 19, 2002 which has issued as U.S. Pat. No. 6,776,690.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates in general to sliders for use in magnetic storage devices, and more particularly to slider fabrication methods and slider designs that facilitate fabrication and even more particularly to lapping requirements of slider designs and methods for lapping surfaces on a slider.
[0004] 2.Description of Prior Art
[0005] A typical prior art head and disk system 10 is illustrated in FIG. 1 . In operation the magnetic transducer 20 is supported by the suspension 13 as it flies above the disk 16 . The magnetic transducer, usually called a “head” or “slider” is composed of elements that perform the task of writing magnetic transitions (the write head 23 ) and reading the magnetic transitions (the read head 12 ). The electrical signals to and from the read and write heads 12 , 23 (collectively “magnetic transducer elements”) travel along conductive paths (leads) 14 which are attached to or embedded in the suspension 13 . Typically there are two electrical contact pads (not shown) each for the read and write heads 12 , 23 . Wires or leads 14 are connected to these pads and routed in the suspension 13 to the arm electronics (not shown). The disk 16 is attached to a spindle 18 that is driven by a spindle motor 24 to rotate the disk 16 . The disk 16 comprises a substrate 26 on which a plurality of thin films 21 are deposited. The thin films 21 include ferromagnetic material in which the write head 23 records the magnetic transitions in which information is encoded. The read head 12 reads magnetic transitions as the disk rotates under the air-bearing surface (ABS) of the magnetic transducer 20 .
[0006] FIG. 2 is a midline section of one type of prior art magnetic transducer 20 shown prior to lapping. The substrate 43 of the slider is typically a hard durable material. The components of the read head 12 shown are the first shield (S 1 ), surround the sensor 105 which is surrounded by insulation layers 107 , 109 and the second shield (P 1 /S 2 ). This type of magnetic transducer is called a “merged head” because the P 1 /S 2 layer serves as a shield for the read head 12 and a pole piece for the write head 23 . The yoke also includes a second pole piece (P 2 ) which connects with P 1 /S 2 at the back. The P 2 curves down over coil 37 to confront the P 1 across the write gap layer to form the write gap at the air-bearing surface (ABS). The zero throat height (ZTH) is defined as the point where the P 2 first touches the gap layer. The sensor 105 includes a magnetoresistive material such as permalloy, but may be a mulitlayered structure containing various layers of ferromagnetic and antiferromagnetic material. The shields and pole pieces are ferromagnetic materials, e.g., NiFe or CoFe. Prior to lapping the materials and structures at the ABS extend beyond the ABS. As illustrated in FIG. 2 the material to the right of the ABS plane is removed by lapping to achieve precise control of the length of the sensor 105 (which is called the “stripe height”) and the distance from the ZTH to the ABS (which is called the “throat height”). The uncertainty of the saw plane causes variations in the stripe height which are on the order of microns and which would lead to unacceptable variations in magnetic performance is not corrected. Lapping is the process used in the prior art to achieve much tighter stripe height control in the nanometer range.
[0007] In the typical process of fabricating thin film magnetic transducers, a large number of transducers are formed simultaneously on a wafer. After the basic structures are formed the wafer may be sawed into quadrants, rows or individual transducers. Further processing may occur at any or all of these stages. Although sawing has been the typical method for separating the wafers into individual sliders, recently reactive ion etching (RIE) or deep reactive ion etching (DRIE) with a flourine containing plasma has been used. The surfaces of the sliders perpendicular to the surface of the wafer that are exposed when the wafers are cut form the air bearing surface (ABS) of the slider.
[0008] After lapping, features typically called “rails” are formed on the ABS of magnetic transducer 20 . The rails have traditionally been used to determine the aerodynamics of the slider and serve as the contact area should the transducer come in contact with the media either while rotating or when stationary.
[0009] U.S. Pat. No. 5,321,882 to Zarouri, et al., discloses a process for forming slider air-bearing surfaces one at a time. The sliders are supported by a mechanical backing while being processed sequentially from a column cut from the wafer. In U.S. Pat. No. 6,093,083 to Lackey, a row of sliders is processed while being rigidly bound to a carrier.
[0010] Sliders may be lapped in rows, but it may be advantageous to have the individual sliders cut out prior to lapping. Even though the sliders have been separated, it is possible to lap several at one time by attaching them to carrier. The time required to lap sliders is a significant element in the cost of manufacturing; therefore, there is a need to improve production efficiency by reducing lapping time, and achieve an ABS surface with a greater control of flatness parameters.
SUMMARY OF THE INVENTION
[0011] A process will be described for fabricating sliders with one or more sacrificial structures (extensions) that reduce the amount of time required for lapping to create the air-bearing surface (ABS). In accordance with the present invention the amount of slider material to be removed by lapping is reduced, and additional lapping or polishing steps are eliminated.
[0012] Prior to separating individual sliders from a wafer, a mask of material that is not removable by deep reactive ion etching (DRIE) is patterned on the surface of the sliders. The mask outlines a sacrificial extension around portions of the magnetic transducer elements that are nearest the predetermined plane which will become the ABS. The sacrificial extension makes the surface of the slider which will be lapped non-planar. The sacrificial extension extends below the predetermined ABS plane. When the sliders are individually separated by DRIE, the shape of the mask including the sacrificial extension is projected down into and along the slider body. The sacrificial extension covers the thin film elements of the read and write heads. The surface of the slider contains a smaller amount of material (with a high aspect ratio) to be removed by lapping relative to prior art designs which require removal of material on the entire planar surface of the slider. The sacrificial extension reduces the amount material to be removed by lapping while maintaining the ability to precisely control the magnetoresistive stripe and throat heights. In one embodiment, additional guide rails are disposed along the outer edges of the slider ABS to facilitate maintaining slider symmetry during the lapping process and prevent the slider from canting to one side. The sacrificial extension and the guide rails are partially or completely removed during the lapping process. The shape of the sacrificial extensions may be optimized for the various embodiments.
[0013] In another embodiment, the sacrificial extension is formed with a cross-sectional shape having a narrow neck which encourages breakage during the ABS lapping process, thus, further accelerating the process. In another embodiment, a channel is disposed on the side of the slider opposite the ABS to provide space for the sacrificial extension of the adjacent slider and allow the sliders to be spaced closer together on the wafer surface for more efficient use of the wafer during head fabrication.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of the nature and advantages of the invention, as well as the preferred modes of use, reference should be made to the following detailed description read in conjunction with the accompanying drawings. In the following drawings, like reference numerals designate like or similar parts throughout the drawings.
[0015] FIG. 1 is a simplified drawing illustrating a magnetic disk drive system of a type in which a slider in accordance with the present invention can be used.
[0016] FIG. 2 is a midline sectional view of a type of prior art magnetic transducer, prior to lapping, illustrating the effect and purpose of lapping the slider.
[0017] FIG. 3 is a partial view of a wafer with a plurality of masks for sliders according to a first embodiment of the invention.
[0018] FIG. 4 shows an isometric view of a slider having a sacrificial extension according to the first embodiment of the invention as shown in FIG. 3 after the DRIE process has cut the slider from the wafer.
[0019] FIG. 5 is an enlarged view of the sacrificial extension shown in the slider of FIG. 4 .
[0020] FIG. 6 is an isometric view illustrating the trailing edge of a slider prior to lapping according to a second embodiment of the invention
[0021] FIG. 7 is an enlarged view of the sacrificial extension shown in FIG. 6 .
[0022] FIG. 8 is a midline sectional view of a slider and mask according to the invention taken perpendicular to the trailing end of the slider (at the left) and the surface to be lapped (at the bottom).
[0023] FIG. 9 is a partial view of a wafer with a plurality of masks for sliders according to a third embodiment according to the invention having a channel on the top surface to allow more efficient use of the wafer.
[0024] FIG. 10 is an isometric view of a slider shown in FIG. 9 having a channel on the top surface to allow more efficient use of the wafer.
[0025] FIG. 11 illustrates the trailing edge of a slider prior to lapping according to an embodiment of the invention having the sacrificial extension and magnetic transducer elements offset from the midline of the slider.
[0026] FIG. 12 illustrates the trailing edge of a slider prior to lapping according to an embodiment of the invention having the magnetic transducer elements and sacrificial extension formed with a narrow neck offset from the midline of the slider.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] FIG. 3 is a partial view of a wafer 52 with a plurality of masks 53 for sliders according to a first embodiment of the invention. The substrate 43 is a material which is amenable to DRIE, for example, silicon. The masks 53 outline the shape of the sliders and the sacrificial extension 32 and optionally the guide rails. The mask 53 is made of a material that is resistant to DRIE, for example, photoresist or alumina. When the wafer 52 is subjected to DRIE with the ions being directed substantially perpendicular to the surface of the wafer, the individual sliders with the sacrificial extension are cut out in the shape of the mask. Although non-RIE-able material in the head structure (not shown) may also be used to define the shape of the sacrificial extension, this has the disadvantage of potentially allowing some of the head material to be sputtered off and redeposited in the kerf and thereby interfering with the clean separation of the sliders. The details of the cross-sectional shape of the sacrificial extension 32 and optional guide rails 34 are determined by the shape of the mask 53 . The shape and dimension of these features will vary according to various embodiments of the invention. The shape of the sacrificial extension need not include a planar surface and, therefore, can include curved and irregular shapes. The mask 53 in combination with DRIE allows the removal or more material between the sliders than is feasible using prior art sawing techniques. By lessening the amount of material to be removed by lapping, the technique of the invention allows the lapping process to proceed more quickly than under the prior art.
[0028] FIG. 4 shows an isometric view of a slider having a sacrificial extension 32 according to the first embodiment of the invention as shown in FIG. 3 after the DRIE process has cut the slider from the wafer. The view of slider 20 in FIG. 4 is of the trailing edge of the slider surface, i.e., the surface that is the last to pass over the moving magnetic media when in use. The guide rails 34 and the sacrificial extension 32 extend the entire length of the slider, from the trailing edge to the leading edge. The head elements 31 are illustrated as a shaded area that extends into the sacrificial extension 32 . The sacrificial extension 32 may also include the anchor base (not shown) which is used in the prior art to support the fragile pole tips during wafer fabrication. The anchor base may, in fact be part of the mask since it is typically made from a material such as NiFe which is not readily etchable in a DRIE process. The internal structure of the head elements 31 are according to the prior art and the details of these structures are independent of the invention. Thus, the invention can be used with any head structure which includes lapping as part of the fabrication process. The head elements 31 include an upper layer of material that is not subject to reactive ion etching (non-RIE-able), for example, CoFe or a NiFe alloy, and, therefore, can be used as part of the mask as well. The body of the slider 43 is a material that is removable by DRIE. Silicon is preferred as a material for the body of the slider, but other RIE-able materials can be used. The embodiment shown includes optional symmetric guide rails 34 that are disposed on the outer edges of the slider bottom surface which will be lapped. The guide rails 34 aid in the lapping process by keeping the lapped surface from canting to one side. The sliders must be held during lapping with the sacrificial extension 32 confronting the lapping plate and may be moved in relation to the lapping plate or the lapping plate may be moved. The guide rails 34 would ideally both be the same height and width, but need not be the same height or width as the sacrificial extension 32 . At some point during the lapping process the surfaces of guide rails 34 and sacrificial extension 32 will become coplanar as protruding material is worn away. The guide rails 34 are distinct from the aerodynamic rails which are used to control the flying characteristics of the slider. The guide rails 34 may be completely removed during lapping as will be noted in more detail hereinafter.
[0029] FIG. 5 is a magnified view of the sacrificial extension 32 from FIG. 4 . This figure illustrates the optional planes at which the lapping process may be terminated. The AA-plane is the bottom of the sacrificial extension 32 prior to lapping. In other embodiments the bottom of the sacrificial extension 32 may be shorter than the guide rails 34 . The BB-plane is one plane at which the lapping may be terminated leaving a portion of the sacrificial extension 32 and the guide rails (not shown) extending below the surrounding slider surface which is shown as plane CC. The lapping may also be continued until the DD-plane is reached at which point the sacrificial extension and the guide rails will have been completely removed, as well as, some material from the slider surface. The plane at which lapping is terminated is typically referred to as the ABS although additional material for overcoats, aerodynamic structures, etc. may be added after lapping which will result in the true, final ABS being slightly lower than the actual lapping plane.
[0030] FIG. 6 shows an isometric view of a slider having a sacrificial extension 32 T according to the second embodiment of the invention. In this embodiment the sacrificial extension 32 T is structurally weak in the transverse direction. because it is formed with a narrow neck (like an inverted “T”) which facilitates breaking to allow a significant amount of material to be removed as lapping begins and therefore tends to further reduce the lapping time. The planes shown in FIG. 7 for optional points to stop lapping and thus define the ABS are the same as illustrated in FIG. 6 and FIG. 4 .
[0031] FIG. 8 is a midline cross-sectional view of a slider and mask according to the invention taken perpendicular to the trailing end 800 of the slider 20 and the surface to be lapped, plane 802 . In this view, the details of the rails are not shown. FIG. 8 shows that the sacrificial extension 32 extends the entire length of slider 20 . The mask 53 covers the entire surface of the slider which is overcoat 61 which has been deposited over the head elements according to the prior art. Plane 802 is indicated for reference as the bottom of the sacrificial extension 32 or an as-lapped ABS surface. The guide rails (not shown) also extend the full length of the slider parallel to the sacrificial extension 32 .
[0032] FIG. 9 is a partial view of a wafer 52 with a plurality of masks 53 C for sliders according to a third embodiment of the invention having a channel 55 in the top surface (the surface parallel to the ABS). FIG. 10 is an isometric view of a slider 20 according to the third embodiment of the invention. A channel 55 is sized to allow the sacrificial extension 32 T or 32 (not shown) to extend into what would otherwise be an adjacent slider. This allows the sliders to be position more densely and, therefore, more efficiently on the wafer. For this efficiency to be achieved the guide rails 34 must not extend as far as the sacrificial extension 32 T or 32 . However, multiple channels 55 may exist in adjacent sliders to accommodate other sacrificial extensions such as guide rails 34 .
[0033] The sacrificial extensions are not necessarily placed along the central plane of the slider. The option exists for placing the magnetic transducer elements off-axis with the sacrificial extension below the sensor. FIG. 11 illustrates the trailing edge of a slider prior to lapping according to an embodiment of the invention having the sacrificial extension and magnetic transducer elements offset from the midline of the slider. Other sacrificial extensions such as guide rails 34 may be formed at other locations on the ABS side of the slider to improve lapping uniformity and/or flatness. As shown in FIG. 11 , for example, the sacrificial extension 32 and guide rails 34 are symmetric about the central plane of the slider. Ideally, this will prevent the skew of the slider. In alternative embodiment illustrated in FIG. 12 the offset sacrificial extension 32 T may be formed with a narrow neck which facilitates breaking as described above. As an example, an inverted “T” structure can be placed off the central axis of the slider with or without other sacrificial extensions to improve the rate of the lapping of the slider.
[0034] One issue for any lapping process is determining when enough material has been removed to achieve the correct stripe height of the sensor and also the throat height of the inductive write head. Electronic lapping guides (ELG's) have been used in the prior art for this purpose. An ELG can be used with the sacrificial extension structure by including it in the guide rails, the sacrificial extension itself or any other portion of the slider which will remain after lapping. In an alternative embodiment of the invention, the sensor structure could be used to determine the stripe height of the sensor and the throat height. Using the sensor has the advantage of allowing a simpler head structure, but adds the complexity of having to electrically connect the sensor structure during lapping without causing any electrical or mechanical damage to the sensor. Using the sensor as a lapping end-point detector is not exclusive to sliders with sacrificial extensions described herein, but can be used an alternative head design and lapping method to achieve a reproducible ABS plane for the slider.
[0035] Except where express materials, thickness values, etc., have been given above, the layers, structures and materials in a slider embodying the invention are according to the prior art and are fabricated according to the prior art.
[0036] The compositions given herein have been described without regard to small amounts of impurities that are inevitably present in practical embodiments as is well known to those skilled in the art.
[0037] Although the embodiments of the invention have been described in a particular embodiment, the invention as described herein is not limited to this application and various changes and modifications will be apparent to those skilled in the art which will be within the scope of the invention. | A process for fabricating sliders with one or more sacrificial structures (extensions) that facilitate lapping to create the air-bearing surface (ABS) is described. Prior to separating individual sliders from a wafer, a mask of material that is not removable by deep reactive ion etching (DRIE) is patterned on the surface of the sliders. The mask outlines a sacrificial extension around portions of the magnetic transducer elements that are nearest the predetermined plane which will become the ABS. The sacrificial extension makes the surface of the slider which will be lapped non-planar. The sacrificial extension extends below the predetermined ABS plane. When the sliders are individually separated by DRIE, the shape of the mask including the sacrificial extension is projected down into and along the slider body. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus for sensing alignment marks on two objects when the two objects are to be aligned with each other and producing two signals representing the sensing, extracting a necessary signal component from each of the signals, and composing the extracted signals to obtain a desirable signal.
2. Description of the Prior Art
As an example, during the patterning in the manufacturing process of semiconductors, a wafer and a mask must be aligned with high accuracy and recently, this is usually accomplished automatically. In the automatic aligning, photoelectric detecting means are generally used to detect the position of an object. For example, in an apparatus of the prior art, the object is scanned by using a laser light as a light source and the light beams scattered from alignment mark patterns W and M on the wafer and mask shown in FIGS. 1A and 1B of the accompanying drawings are photoelectrically detected by a photodiode. By utilizing the fact that the output signal thereof includes the information on the distance between the patterns W and M, the relative position of the wafer and mask is detected. Such aligning is accomplished by directing the mark patterns W and M detected in the described manner into a positional relation as shown in FIG. 1C. The mark patterns W and M and a pattern constituting an actual element are in a predetermined relation and therefore, if the mark patterns W and M are directed into a predetermined positional relation, the actual element patterns on the wafer and mask are properly aligned. If the positional relation between the mark patterns W and M is detected, the difference between that positional relation and the predetermined relation may be examined and a driving mechanism may be operated so that this difference becomes null. The aligning of the wafer and mask requires all degrees of two-dimensional freedom to be controlled and is usually accomplished by observing a plurality of locations on the wafer and mask.
The alignment marks depicted in FIGS. 1A and 1B are known from U.S. Pat. No. 4,167,677 of the present assignee.
On the other hand, when the coherent lights coming back from at set of marks on the wafer and mask are detected by a single photoelectric detector, the two lights interfere with each other to provide an unstable signal and this has led to the disadvantage that automatic aligning becomes impossible or the accuracy of aligning deteriorates.
In a specific example shown in FIG. 5 of U.S. Pat. No. 4,251,129 of the present assignee, the light signals from the wafer and mask are detected by different photoelectric detectors, whereby a stable signal is obtained. However, even if great improvements have been made by this apparatus, undesirable signals concerning the mark of another object to be detected can remain in the signals of the detectors.
SUMMARY OF THE INVENTION
It is an object of the present invention to create a signal for aligning two objects with high accuracy.
It is another object of the present invention to obtain an alignment signal in which undesirable signals have been removed from the output signal streams of different sensors when two objects have been sensed by the different sensors.
It is still another object of the present invention to provide an automatic aligning apparatus which separately detects light signals coming back from a mask and a wafer, which are the objects to be aligned, extracts and composes necessary signal components, and effects aligning highly accurately. More specifically, such apparatus produces a plurality of detection signals with a plurality of photoelectric detectors disposed with respect to a mark pattern which is on the object, extracts necessary signal components from each of the detection signals and composes these extracted signals.
It is yet still another object of the present invention to effect coarse alignment of a mask and a wafer, and thereafter effecting fine alignment thereof.
The invention will become fully apparent from the following detailed description thereof taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A, 1B and 1C illustrate the mark patterns of a wafer and a mask.
FIG. 2 is a block circuit diagram showing the basic construction of an embodiment of the aligning signal processing apparatus according to the present invention.
FIG. 3 is a time chart for explaining the operation of the circuit.
FIG. 4 is a time chart showing the signal waveforms in a case where the relative position of the wafer and mask greatly deviates from the predetermined position due to unsatisfactory installation of wafer.
FIG. 5 is a detailed block circuit diagram of the elements shown in FIG. 1.
FIG. 6 is a cross-sectional view of a mark detecting optical system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 2, reference numeral 1 designates a first photoelectric detector for detecting a light signal coming back from a wafer, and reference numeral 2 denotes a second photoelectric detector for detecting a light signal from a mask. These photoelectric detectors 1 and 2 are disposed, for example, in the mark detecting device of FIG. 6. In FIG. 6, MA designates a mask provided with a semiconductor circuit pattern, WA denotes a wafer provided with a photoresist layer, and PL designates a projection lens, which makes the mask MA and the wafer WA conjugate. M designates the alignment mark of the mask and W denotes the alignment mark of the wafer. OL designates an objective lens, RL denotes relay lenses, and CL designates a condenser lens. HM designates a half-mirror, MD denotes a mirror drum rotated at a high speed, BS designates a polarizing beam splitter, Q denotes a quarter wave plate, and LS designates a laser light source which produces a linearly polarized laser beam. The laser beam emitted from the laser light source LS scans the marks M and W by means of the mirror drum MD, while the light from the mark W mainly enters the photoelectric detector 1 and the light from the mark M mainly enters the photoelectric detector 2.
The photoelectric detectors 1 and 2 of FIG. 2 are respectively connected to first and second signal amplitude discriminating circuits 3 and 4 which convert an analog signal into a digital signal. The outputs of these first and second signal amplitude discriminating circuits 3 and 4 are delivered to first and second signal extracting circuits 5 and 6 which extract only necessary signal components, and also are put out to a control circuit 7. A command signal is supplied from the control circuit 7 to the first and second signal amplitude discriminating circuits 3 and 4 and to the signal extracting circuits 5 and 6 and, in accordance with this command signal, signals obtained in the signal extracting circuits 5 and 6 are put out to a signal composing circuit 8.
When, for example, the mark patterns W and M of the wafer and mask are in a positional relation as shown in part (a) of FIG. 3, the mark pattern W of the wafer is detected by the first photoelectric detector 1 under the scanning of the laser light L. The detection signal S W detected by the first photoelectric detector 1, as shown in part (b) of FIG. 3, includes, in addition to the pattern signals 10 by the original mark pattern W, unstable signals 11 of the mark pattern M of the mask produced by interference phenomenon. On the other hand, the detection signal S M shown in part (e) of FIG. 3 detected by the second photoelectric detector 2 includes, in addition to pattern signals 12 based on the mark pattern M of the mask, the signals 13 having low level by the mark pattern W of the wafer. Scanning of the laser light L is effected several times, but these detection signals S W and S M are obtained at the time of each scanning.
If, as shown in part (a) of FIG. 3, the positional relation between the mask and the wafer is such that the mark pattern W of the wafer lies between each two parallel ones of the four mark patterns M on the mask, the second and fifth signals in the detection signal S W shown in part (b) of FIG. 3 and the signal S M shown in part (e) of FIG. 3 are the signals obtained from the mark pattern W and the remaining, namely, the first, third, fourth and sixth signals, are the signals detected from the mark patterns M.
The following technique is used to extract only the signals 10 representing the mark pattern W on the wafer from the detection signal S W and only the signals 12 representing the mark patterns M on the mask from the detection signal S M . First, the detection signal S W or S M is converted into a digital signal. Then there is created an extraction command signal 14 shown in part (c) of FIG. 3, which is put out at the timing from the end of the first pulse to the end of the second pulse, and from the end of the fourth pulse to the end of the fifth pulse of said converted signal or the signal composed of the two signals S W and S M , along with a signal 15 shown in part (f) of FIG. 3 which is an inverted signal of the signal 14. Subsequently, by the use of these extraction command signals (c) and (f), the signal 16 for only the mark pattern W on the wafer and the signal 17 for only the mark patterns M on the mask can be extracted. This extraction is accomplished by generating the extraction command signals 14 and 15 in the control circuit 7 from the signals supplied thereto through the first and second signal discriminating circuits 3 and 4, and by delivering the extraction command signals 14 and 15 to the first and second signal extracting circuits 5 and 6. The thus obtained extraction signals 16 and 17 shown in parts (d) and (g) of FIG. 3 are composed by the signal composing circuit 8, whereby there is obtained a stable signal 18 shown in part (h) of FIG. 3 which corresponds to the relative position of the mark patterns W and M on the mask and wafer. This signal 18 can be processed in the same manner as in the prior art to recognize, with high accuracy, the relative position of the mark patterns W and M. Particularly in this case, the unnecessary signals 11 and 13 have been removed and therefore, the resultant composite signal 18 is free of any indistinctness due to the influence of these unnecessary signals.
When the mark patterns W and M are not in the positional relation as shown in part (a) of FIG. 3, that is, for example, when they are disposed in the positional relation as shown in part (a) of FIG. 4, coarse aligning may be effected, in the manner as will now be described, until the positional relation as shown in part (a) of FIG. 3 is attained. That is, the detection signal S W shown in part (b) of FIG. 4 obtained by the first photoelectric detector 1 and coming back from the wafer and the detection signal S M shown in part (c) of FIG. 4 detected by the second photoelectric detector 2 and coming back from the mask are converted into digital signals by the first and second signal amplitude discriminating circuits 3 and 4. Thereafter a signal 20 shown in part (d) of FIG. 4 which comprises the digital signals superposed one upon the other is obtained and aligning is effected by the use of the same means as that of the prior art.
In this case, the detection signals S W and S M are detected just at the same time and moreover, they include stable signals of the mark patterns W and M of the wafer and mask. Therefore, even if unstable signal components exist in the signals S W and S M , signal 20 will not have pulses other than six pulses. However, the pulse width may sometimes fluctuate under the influence of unstable signals and therefore, the signal 20 cannot be utilized for the signal processing for highly accurate alignment.
FIG. 5 shows the details of the signal amplitude discriminating circuit 3, the signal extracting circuit 5 and the control circuit 7 to clarify the functions of the circuit elements shown in FIG. 2. A comparator circuit 31 is included in the signal amplitude discriminating circuit 3 which is adapted to amplitude-discriminate the signal by a potential put out from a D/A converter 71 in the control circuit 7. Logical multiply gates 51 and 52 for extracting only the necessary signal from the digital signal input are provided in the signal extracting circuit 5. The logical multiply gate 51 is directly subjected to the control from a micro computer 72 in the control circuit 7 and the logical multiply gate 52 detects a signal under the control of a decoder 73 in accordance with the order of the pulses. A logical sum gate 53 for selecting the outputs of logical multiply gates 51 and 52 is further provided in the signal extracting circuit 5. The D/A converter 71 converts the digital potential command of the micro computer 72 into an analog potential, a counter circuit 74 counts the pulse number of the signal, and the decoder 73 decodes the count content of the counter circuit 74 and puts out a signal extraction command to the logical multiply gate 52 at required timing. In the case of processing in which extraction command signal 14 shown in FIG. 3(c) is produced, the values "1" and "4" counted by the counter circuit 74 are utilized so that signal 14 is produced between the end of the first pulse and the end of the second pulse, and between the end of the fourth pulse and the end of the fifth pulse as described above. Accordingly, the decoder 73 decodes the count values "1" and "4" and decodes them. The micro computer 72 supplies commands, as required to respective processing components, to the D/A converter 71, the logical multiply gate 51 taking charge of the signal extracting function, and the decoder 73.
It is also possible to control the first and second signal extracting circuits 5 and 6 from the control circuit 7 to effect selection such that only the detection signal S W obtained by the first photoelectric detector 1 is taken out as the output of the signal composing circuit 8 or only the detection signal S M put out from the second photoelectric detector 2 is taken out as the output of the signal composing circuit 8 or, like the signal 20 shown in FIG. 4(d), the outputs of the detection signals S W and S M are superposed one upon the other. Accordingly, when the number of the output signals of the signal composing circuit 8 is over or under a predetermined number, an abnormal condition such as admixture of erroneous signals due to dust or the like or unsatisfactory installation of the mask and wafer can be recognized. Further, where the installed position of the wafer greatly deviates from the standard position, the wafer can be moved, by the coarse automatic aligning described in connection with FIG. 4, to a position whereat the signal processing for higly accurate automatic aligning can be performed. In the described embodiment, the photoelectrically detected detection signals S W and S M are immediately converted into digital signals, whereby the processing such as signal extraction or composition is effected. However, the photoelectrically detected analog signals may be directly subjected to the signal processing such as extraction or composition.
The foregoing specific embodiment has been described with reference to a pair of mark patterns of the mask and wafer. However, in order to actually realize two-dimensional alignment of two objects, it is necessary to detect mark patterns at least two positions.
Also, in FIG. 2 there are disposed two photoelectric detectors, but the number of the photoelectric detectors may be increased in some cases. | An apparatus for processing a signal for aligning a first object having at least one standard mark thereon with a second object having at least one reference mark thereon, includes a first sensor for sensing the standard mark, second sensor for sensing the reference mark through the first object, an illumination source for illuminating the standard mark and the reference mark, a first extracting circuit for extracting a signal concerning the standard mark from the signal stream of the first sensor, a second extracting circuit for extracting a signal concerning the reference mark from the signal stream of the second sensor, and a signal composing circuit for composing the signal concerning the standard mark and the signal concerning the reference mark. | 6 |
This application claims the priority benefit of Taiwan Patent Application Serial Number 093141561 filed Dec. 31, 2004, the full disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid crystal display, and more particularly, to a bistable liquid crystal display.
2. Description of the Related Art
Bistable liquid crystal displays have received considerable attention recently because they can operate at lower power levels at their two stable states without the application of any electric field.
Among the bistable devices, the bistable twisted nematic liquid crystal cell can be switched between the (ψ−π) and (ψ+π) twisted states by controlling the flow effect. However, the durations for the liquid crystal maintaining these two states are not very long. Indeed, the intermediate ψ state is more stable. Although a long-term bistability has been achieved by using multidimensional alignment structure to prevent the liquid crystal of the ψ state from nucleation, the application is still limited. To make the states of the liquid crystal truly stable, the π-BTN liquid crystal cells including BiNem, COP-BTN and SCBN-LC, which also use flow effect to switch between ψ state and (ψ+π) state, are demonstrated one after another. However, the BiNem and COP-BTN liquid crystal cells need asymmetric anchoring energy substrates in order to achieve anchoring energy breaking and the SCBN-LC and COP-BTN liquid crystal cells need three-terminal electrode structure to produce the horizontal and vertical fields to switch states. The manufacture processes of these special substrates are not only difficult to be controlled but also difficult to match the standards for LC display. There are also other designs of the bistable display such as the ZBD (Zenithal Bistable Display) and the micro-patterned surface alignment device that have very long-term bistability. However the substrates of the ZBD which have the microstructure relief grating with short pitch and deep profile, and the micro-patterned surface alignment device which use the atomic force microscope (AFM) nano-rubbing technique to have orientational patterns are even more delicate and not easy to be manufactured.
In view of the above reasons, there exists a need for a bistable liquid crystal display which overcomes the above-mentioned problems in the prior art. This invention addresses this need in the prior art as well as other needs, which will become apparent to those skilled in the art from this disclosure.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a bistable liquid crystal display that can be driven to switch between two stable states thereof by applying driving signals of different frequencies.
In one embodiment, the bistable liquid crystal display includes two opposing upper and lower substrates, two transparent electrode layers, two alignment layers, two polarizers, a signal source and a liquid crystal layer. The two transparent electrode layers are disposed respectively on the upper and lower substrates and between the upper and lower substrates. The two alignment layers are disposed respectively on the two transparent electrode layers. The upper polarizer is disposed above the upper substrate and lower polarizer is disposed under the lower substrate. The liquid crystal layer is disposed between the two alignment layers and has a plurality of dual frequency liquid crystal molecules. The liquid crystal layer has a stable tilted homeotropic state and a stable twisted state. When a first driving signal of first frequency generated by the signal source is applied to the liquid crystal layer for a first predetermined period of time and then the application of the first driving signal to the liquid crystal layer stops, the liquid crystal layer will switch to the tilted homeotropic state. A second driving signal of second frequency generated by the signal source is applied subsequently to the liquid crystal layer for a second predetermined period of time and then the application of the second driving signal to the liquid crystal layer stops, the liquid crystal layer will switch to the twisted state.
In another embodiment, the bistable liquid crystal display includes all the elements of the bistable liquid crystal display described in the above embodiment except that a dichromatic dye is dispersed within the liquid crystal molecules to substitute the two polarizers.
It is another object of the present invention to provide a method for driving a bistable liquid crystal display so that the display can be driven to switch between two stable states thereof by applying driving signals of different frequencies.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing a bistable liquid crystal display according to an embodiment of the present invention.
FIG. 2 is a schematic diagram showing a bistable liquid crystal display according to another embodiment of the present invention.
FIGS. 3 a and 3 b show that switches between two driving signals cause the liquid crystal layer of the liquid crystal display according to the present invention to switch between the tilted homeotropic state and the twisted state.
FIG. 4 shows the transient transmittance of the bistable liquid crystal layer according to the present invention from T state to TH state and the corresponding voltages applied to the liquid crystal layer.
FIG. 5 shows the transient transmittance of the bistable liquid crystal layer according to the present invention from TH state to T state and the corresponding voltages applied to the liquid crystal layer.
FIG. 6 shows the microscopic pictures of TH state, BH state, T state and BT state with a He—Ne laser as a light source to illuminate the liquid crystal layer.
FIGS. 7-9 show the static simulation results of the bistable liquid crystal display according to the present invention
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is now made to FIG. 1 where there is shown a bistable liquid crystal display 100 according to an embodiment of the present invention. The liquid crystal display 100 includes two opposing upper and lower substrates 11 , 12 . Two electrode layers 21 , 22 made from transparent indium tin oxide (ITO) are disposed respectively on the upper and lower substrates 11 , 12 and between the substrates 11 , 12 . Two alignment layers 31 , 32 formed by e.g. coating the RN-1338 material of Nissan Chemicals Co. are disposed on the electrode layers 21 , 22 respectively and between the electrode layers 21 , 22 . The alignment layers 31 , 32 have a pre-tilt angle of smaller than 87 degrees, preferably from 45 to 87 degrees and are made from e.g. a rubbing material or an optical material. An upper polarizer 41 is disposed above the upper substrate 11 and a lower polarizer 42 is disposed under the lower substrate 12 . The angle between the absorption axes of the polarizers 41 , 42 ranges from about 80 to 100 degrees. The angle between the absorption axis of the upper polarizer 41 and the alignment direction of the alignment layer 31 ranges from 0 to 180 degrees. A liquid crystal layer 50 is disposed between the alignment layers 31 , 32 and has a plurality of dual frequency liquid crystal molecules 51 , for example, MLC-2048 materials of Merck Co. The MLC-2048 material has a dielectric anisotropy (Δ∈) of 3.22 at frequency of 1 KHz and a dielectric anisotropy of −3.4 at frequency of 100 KHz.
In addition, the ratio of the thickness (d) of the liquid crystal layer 50 to the pitch (p) of the liquid crystal molecule 51 ranges from 0.01 to 1.55, preferably from 0.8 to 1.05. The splay elastic constant K 11 , twist elastic constant K 22 and bend elastic constant K 33 of the molecules 51 have relations as follows: K 33 /K 11 >0.865, K 22 /K 11 <0.98.
Reference is now made to FIG. 2 where there is shown a bistable liquid crystal display 200 according to another embodiment of the present invention. The liquid crystal display 200 includes two opposing upper and lower substrates 11 , 12 . Two electrode layers 21 , 22 made from transparent indium tin oxide (ITO) are disposed on the upper and lower substrates 11 , 12 respectively and between the substrates 11 , 12 . Two alignment layers 31 , 32 formed by e.g. coating the RN-1338 material of Nissan Chemicals Co. are disposed on the electrode layers 21 , 22 respectively and between the electrode layers 21 , 22 . The alignment layers 31 , 32 have a pre-tilt angle of smaller than 87 degrees, preferably from 45 to 87 degrees and are made from e.g. a rubbing material or an optical material.
The differences between the display 200 of FIG. 2 and the display 100 of FIG. 1 are that polarizers are not necessary for the display 200 and dichromatic dyes 60 are dispersed within a plurality of dual frequency liquid crystal molecules 51 between the alignment layers 31 , 32 . The liquid crystal molecules 51 and the dichromatic dyes 60 collectively form a liquid crystal layer 50 ′. The dual frequency liquid crystal molecules 51 , for example, MLC-2048 materials of Merck Co. still have a dielectric anisotropy (Δ∈) of 3.22 at frequency of 1 KHz and a dielectric anisotropy of −3.4 at frequency of 100 KHz.
In addition, the ratio of the thickness (d) of the liquid crystal layer 50 to the pitch (p) of the liquid crystal molecule 51 ranges from 0.01 to 1.55, preferably from 0.8 to 1.05. The splay elastic constant K 11 , twist elastic constant K 22 and bend elastic constant K 33 of the molecules 51 have relations as follows: K 33 /K 11 >0.865, K 22 /K 11 <0.98.
Referring to FIGS. 3 a and 3 b , they show that the switches between two driving signals cause the liquid crystal molecules of the liquid crystal display according to the present invention to switch between the tilted homeotropic state and the twisted state. A signal source 70 is used as a signal generator for the bistable liquid crystal displays 100 , 200 of the present invention and capable of generating driving signals of different frequencies and/or different voltages to drive the molecules 51 in the liquid crystal layers 50 , 50 ′. As the liquid crystal layers 50 , 50 ′ are in the stable twisted state (T state), an application of a lower frequency f 1 driving signal for a predetermined period of time will render the liquid crystal layers 50 , 50 ′ switch to the biased homeotropic state (BH state) and the dielectric anisotropy (Δ∈) of the liquid crystal molecules 51 changes to a value of greater than zero. After finishing the application of the frequency f 1 driving signal, the liquid crystal layers 50 , 50 ′ will switch to the stable titled homeotropic state (TH state). An application of another frequency f 1 driving signal to the liquid crystal layers 50 , 50 ′ of the TH state will render them come back to the BH state. A subsequent application of a higher frequency f 2 driving signal to the liquid crystal layers 50 , 50 ′ will render them switch to the biased twisted state (BT state) and the dielectric anisotropy (Δ∈) of the liquid crystal molecules 51 change to a value of smaller than zero. After finishing the application of the frequency f 2 driving signal, the liquid crystal layers 50 , 50 ′ will come back to the stable T state.
To implement the bistable liquid crystal display 100 , an indium tin oxide (ITO) glass is used as the substrates 11 , 12 and the RN-1338 of Nissan Chemicals Co. is spin coated thereon to form the tiled-homeotropic alignment layers 31 , 32 . The rubbing directions of the alignment layers are anti-parallel. The dual frequency liquid crystal material 51 used in the liquid crystal layer 50 is MLC-2048 of Merck Co. with Δ∈=3.22 at frequency of 1 KHz and Δ∈=−3.4 at frequency of 100 KHz. The substrates 11 , 12 are combined together by using 9.9-micron spacers mixed with adhesive and the MLC-2048 material with a pitch of 10 microns is filled between the substrates 11 , 12 . As the liquid crystal cell is first assembled, the TH state and T state of the liquid crystal molecules 51 will coexist. After applying a 1 KHz driving signal, the liquid crystal layer 50 will present a dark state under crossed polarizer condition.
The optical properties of the liquid crystal layer 50 are measured under a crossed polarizer condition. The light source is He—Ne laser with a wavelength of 632.8 nm. If the liquid crystal layer 50 is in the TH state or BH state, the light goes through the liquid crystal layer 50 with little phase retardation so that the appearance of the liquid crystal layer 50 is dark and the transmittance is low. On the other hand, if the liquid crystal layer 50 is in the T state or BT state, the transmittance is higher.
FIG. 4 shows the transient transmittance of the bistable liquid crystal layer 50 from the T state to TH state. The driving signal applied to the liquid crystal layer 50 is 5 volts with a frequency of 1 KHz. Therefore, the liquid crystal molecules 50 are positive anisotropic when the signal is applied. The transmittance of the liquid crystal layer 50 oscillates due to the phase retardation change when the twisted liquid crystal molecules 51 are pulled to the vertical direction and most of the liquid crystal molecules 51 are vertically aligned (BH state), the liquid crystal layer 50 is dark. When the applied voltage is off, the liquid crystal molecules 51 relax to the TH state, which the transmittance is also very low.
To switch from the TH state to the T state, a driving signal of 5 volts, 1 KHz is applied to the liquid crystal layer 50 first. The liquid crystal molecules 51 are in the BH state and the transmittance of the liquid crystal layer 50 is almost unchanged. Then, the frequency of driving signal is changed to 100 KHz suddenly, the liquid crystal molecules 51 of the middle director tilt down in the opposite director due to the back flow effect. Finally, the liquid crystal molecules 51 are in the T state. The transmittance oscillates also due to the phase retardation change and at last the liquid crystal layer 50 is in the BT state. When the applied signal is off, the liquid crystal layer 50 relaxes to the T state, which is a bright state. FIG. 5 shows the results of the process.
FIG. 6 shows the microscopic pictures of TH state, BH state, T state and BT state under the crossed polarizer condition with rubbing direction parallel to the polarizer. The TH state is not as dark as BH state because the directors of the TH state are tilted with a helical structure and a very small conic angle if misalignment of the substrates exists when most directors of the BH state are vertically aligned. When a He—Ne laser is used as a light source, the BT state is reddish while the T state is greenish, and therefore the BT state has a higher transmittance but is darker as taking picture under the microscope.
Reference is now made to FIG. 7 where there is shown the static simulation result of the bistable liquid crystal display according to the present invention, wherein the abscissa is tilted angle of middle director of liquid crystal layer in degree and the ordinate is energy of liquid crystal molecules in μJ/m 2 . The splay elastic constant K 11 , twist elastic constant K 22 and bend elastic constant K 33 of the liquid crystal molecule is 17.34, 9.597 and 30.26 respectively. The thickness of the liquid crystal layer is 9.9 μm. The pitch of the liquid crystal molecule is 10 μm and the pre-tilt angle of the alignment layers is 75 degrees. As shown in FIG. 7 , there are two local minima in the curve of simulation. Such a result reflects the fact that the liquid crystal layer has two stable states in the bistable liquid crystal display, wherein one is the TH state and the other is the T state. The local maximum in the curve of simulation indicates the energy barrier required to overcome when the liquid crystal layer is driven to switch from its one stable state to another.
FIGS. 8 and 9 show the static simulation results of the bistable liquid crystal display according to the present invention under the condition of different pre-tilt angles. All the parameters except pre-tilt angles used to obtain the simulation results in FIGS. 8 and 9 are identical to the parameters in FIG. 7 . Thus, any further illustrations regarding the parameters are omitted herein. As shown in FIGS. 8 and 9 , each curve of simulation has two local minima and one local maximum. In other words, the liquid crystal layers in the bistable liquid crystal displays according to the present invention have two stable states under the condition of pre-tilt angles ranging from 0 to 87 degrees.
Reference is now made to Table 1 where there is shown the range of the ratio (d/p) of the liquid crystal layer thickness (d) to the pitch (p) of liquid crystal molecules under the condition of different pre-tilt angles when the liquid crystal layer has two stable states. As shown in Table 1, the ratios (d/p) range from 0.01 to 1.55 under the condition of liquid crystal layer thickness of 9.9 μm and pre-tilt angles ranged from 0 to 87 degrees when the liquid crystal layer has two stable states.
TABLE 1
pre-tilt
thickness
angle
(μm)
range of d/p
0°
9.9
0.01~1.45
5°
9.9
0.01~1.35
15°
9.9
0.01~1.4
25°
9.9
0.05~1.45
35°
9.9
0.01~1.45
45°
9.9
0.1~1.5
55°
9.9
0.3~1.5
65°
9.9
0.55~1.55
75°
9.9
0.75~1.55
85°
9.9
1.0~1.55
87°
9.9
1.0~1.1
Tables 2, 3 and 4 show the range of the ratio (d/p) of the liquid crystal layer thickness (d) to the pitch (p) of liquid crystal molecules under the condition of different K 11 , K 22 and K 33 when the liquid crystal layer has two stable states. As shown in the tables, the ratios (d/p) range from 0.01 to 1.55 under the condition of K 33 /K 11 >0.865 and K 22 /K 11 <0.98 when the liquid crystal layer has two stable states.
TABLE 2
K11 = 17.34, K22 = 9.597, K33 = 25.0
pre-tilt
thickness
angle
(μm)
range of d/p
5°
9.9
0.01~1.5
15°
9.9
0.01~1.5
25°
9.9
0.01~1.35
35°
9.9
0.1~1.35
45°
9.9
0.3~1.2
55°
9.9
0.45~1.15
65°
9.9
0.65~1.15
75°
9.9
0.8~1.15
85°
9.9
1.0~1.15
TABLE 3
K11 = 17.34, K22 = 9.597, K33 = 16.0
pre-tilt
thickness
angle
(μm)
range of d/p
5°
9.9
0.01~1.25
15°
9.9
0.2~1.25
25°
9.9
0.35~1.2
35°
9.9
0.4~0.95
45°
9.9
0.5~0.85
55°
9.9
0.6~0.8
65°
9.9
0.7~0.8
70°
9.9
0.7~0.75
TABLE 4
K11 = 17.34, K22 = 14.5, K33 = 30.26
pre-tilt
thickness
angle
(μm)
range of d/p
5°
9.9
0.01~1.3
15°
9.9
0.05~1.3
25°
9.9
0.15~1.15
35°
9.9
0.25~1.05
45°
9.9
0.4~0.95
55°
9.9
0.5~0.95
65°
9.9
0.6~0.95
75°
9.9
0.75~0.95
85°
9.9
0.85~0.95
Although the preferred embodiments of the invention have been disclosed 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. | A bistable chiral tilted-homeotropic nematic liquid crystal (BCTHN) display can be switched between the tilted-homeotropic state (TH state) and the twisted state (T state) by using dual frequency liquid crystal material. These two states can be maintained without the application of any electric field. The bistable liquid crystal display does not need high voltage to induce the flow of liquid crystal or break the anchoring energy. | 6 |
BACKGROUND
[0001] The invention relates to a rotary evaporator having a distilling flask, receiving a distillate and supported rotationally around an axis, which comprises a vapor tube encompassing the axis, a cooler comprising a cooling spiral receiving a coolant and connected to a cooling circuit to form a flow path, and a distillate flask to receive the distillate, with the vapor tube connecting the distilling flask to the cooler and the distillate flask, the distilling flask being heated by a heater, the distilling flask being rotational around the axis by a drive during the heating process, and the vapor guided through the vapor tube and condensed at the cooling spiral can be collected in the distillate flask.
[0002] The invention further relates to a method for evaporating a material to be distilled matter, with the material to be distilled being evaporated at least partially by being inserted into a distilling flask that receives the material to be distilled that is supported rotationally around an axis, with the distilling flask with the material to be distilled being heated by a heater, with the distilling flask being rotated around the axis during the heating process by a drive, with the vapor formed due to heating being guided via a vapor tube encompassing the axis into a cooler, with said cooler comprising a cooling spiral, which is connected to a coolant circuit in order to form a flow path for a coolant, and with a coolant flowing through it, and the vapor condensing at the cooling spiral being collected in a distillate flask.
[0003] Such rotary evaporators and methods for evaporating a material to be distilled are known, for example from the professional article M. T. Kramer: A Rotary Evaporator System And Its Potentials , G-I-T-Fachz. Lab., 18 th Volume, September 1974, page 862ff, and have been largely proven in practice. A feature of the rotary evaporator particularly to be emphasized comprises that by the rotation of the distilling flask during the heating process, the material to be distilled is heated more evenly compared to conventional methods, particularly by a wide-range precipitation of the interior wall of the distilling flask with the material to be distilled. Thus, such rotary evaporators serve very well in lab technology.
[0004] From WO 96/05901 a method is known for regulating and controlling a distillation or condensing apparatus comprising a boiler, a heat source, and a cooler, with the cooling water circulating through the cooler accepting its temperature in the circuit and when it reaches an upper temperature limit, it is replaced by adding cold water until a lower temperature limit is reached. Here, a defined cut-off can be set if, in spite of inserting cold water, any reduction of the temperature of the cooling water fails to occur.
SUMMARY
[0005] The invention is based on the object of providing a rotary evaporator and a method for evaporating a material to be distilled suitable for the use in an automated operation.
[0006] In order to attain this object, in a rotary evaporator of the type mentioned at the outset it is provided that a first temperature sensor is arranged at a first position in the flow path of the coolant and a second temperature sensor is arranged at a second position in the flow path, with the first position being spaced apart from the second position by a section of the flow path of the coolant, and that means are provided to determine the flow rate of the coolant through the section. This way, information can be gathered about the present cooling performance of the cooler, which can be used for various processing steps of an automated operation.
[0007] The section comprises at least a portion of the section in the flow path of the coolant, in which the coolant accepts the condensation heat emitted during the condensation of the vapor. The section of the flow path can therefore form a real partial section of the cooling spiral. In this case, the temperature sensors are arranged in the cooling spiral inside the cooler.
[0008] It is particularly beneficial if the section is selected as large as possible, and particularly comprises the cooling spiral. This way it is achieved that the influence of the measurement inaccuracies during the temperature measurement are kept small compared to the temperature differences measured between the temperature sensors.
[0009] For a determination of the temperature of the coolant entering the cooler as precise as possible it may be provided that the first temperature sensor is arranged at the inlet of the cooling spiral into the cooler. The temperature sensor is therefore arranged in the area of the inlet of the coolant line of the cooling circuit into the cooler, forming the flow path, with the position of the temperature sensor being selected such that any falsification of the temperature measurement due to environmental influences is avoided, for example by heating or cooling of a part of the coolant line between the cooling spiral and the temperature sensor due to environmental influences.
[0010] Additionally, it may be provided that the second temperature sensor is arranged at the outlet of the cooling spiral out of the cooler. Here, too, the arrangement of the temperature sensor is selected in the flow path such that any change in temperature of the coolant after having left the cooling spiral and prior to reaching the temperature sensor is practically excluded. This may also be achieved by suitable heat insulation of the pipes of the cooling spiral in these sections.
[0011] For any statement concerning the cooling performance it is necessary to know the amount of coolant transported through the cooler per time unit. The determination of the flow rate of the coolant can occur, for example, by predetermining a flow rate, for example by predetermining a pressure in the cooling circuit and limiting the flow rate in the flow path, or by measuring the actual flow rate. An embodiment in which the actual flow rate can be measured may provide that the means for determining the flow rate of the coolant through the section of the flow path of the coolant comprises a flow meter.
[0012] Here, it is particularly beneficial when the flow meter in the flow path of the coolant is arranged outside the temperature measurement section of the flow path of the coolant. This way, any falsification of the measured temperature difference is avoided in reference to the actual temperature change caused by the cooling in the cooling spiral and/or the section due to the flow meter, particularly its heat radiation and head emissions, or by a heating of the coolant in the flow meter. It is further advantageous that the flow meter remains more easily accessible in an arrangement outside the section, for example for maintenance or control measures.
[0013] Particularly beneficial conditions develop during the evaporation of the product to be distilled if the cooler is connected to a vacuum generator.
[0014] An embodiment of the invention may provide that means for the determination and/or detection of the temporal progression of the temperature difference between the first and the second temperature sensor and the temporal progression of the flow rate is embodied. Here, it is advantageous that information concerning the changes of the operating state or the features of the material to be distilled can be yielded and used for an automated operation.
[0015] For example, it may be provided that means are embodied for the calculation of the distillate collected in the distillate flask within a certain period of time from the temporal progression of the determined temperature difference and from the temporal progression of the flow rate of the coolant through the section of the flow path of the coolant. This way, the rotary evaporator can be operated for example in an automated fashion until a predetermined amount of distillate has been obtained.
[0016] For an embodiment of the rotary evaporator to process various materials to be distilled it may be provided that means are provided to input and/or save and/or select product-specific information of the material to be distilled and/or the distillate and/or the coolant. Preferably such material-specific data is at least provided by statements concerning the specific thermal capacity of the coolant and/or the distillate, the condensation enthalpy of the distillate, and/or the effectiveness of the transfer of condensation heat into heating of the coolant. From this data the amount of heat can be determined that is fed to the coolant in the cooling circuit per time unit which is equivalent to the heat released during the condensation of the vapor into distillate. Here, the amount of heat results from the amount of coolant, its temperature change, and its specific heat capacity, based on known laws of physics.
[0017] It has shown that in the area of the operating temperature of the coolant its heat capacity can be changed only slightly. In this case, the temperature of the coolant is not included in the calculation but it can be assumed to be constant. Thus, an advantageous embodiment provides that only the difference between the temperatures at the first and the second temperature sensor is determined.
[0018] In order to perform automated processing at the rotary evaporator, a control unit can be provided, by which a control signal can be deduced for the rotary evaporator from the temporal progression of the temperature difference between the first and the second temperature sensors and the temporal progression of the determined flow rate. This way, the information about the operating status and/or process progression yielded during the operation of the rotary evaporator can be used for an automatic control by evaluating and utilizing the control signals generated by the control.
[0019] According to one embodiment of the invention it may be provided that means are embodied for monitoring the temporal progression of the determined temperature difference for temporal changes, particularly computing means, and that using said means information can be gathered from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate concerning the beginning and/or the end of the evaporation of a component of the distillation matter, with the control signal being able to output this information and/or the change of the heating performance of the heater and/or the pressure in the system. Here, it is advantageous that changes in the operation of the rotary evaporator can be detected. For example, the temperature difference may drop to zero at the end points of the cooling spiral or the section when the component of the material to be distilled located in the distilling flask has evaporated entirely or when the material to be distilled remaining in the distilling flask forms an azeotropic, with its evaporation temperature being altered in reference to the evaporation temperature of the components. This way, the shut-off may be triggered for the heater or the rotary evaporator and/or a change of the pressure may be caused in the system via the control signal.
[0020] In order to attain this object in a method of the type mentioned at the outset, it is provided that the difference of the temperatures of the coolant between two points in the flow path of the coolant, which are spaced apart from each other by a section of the flow path of the coolant is determined continuously or at regular intervals and that the flow rate of the coolant through the cooling spiral is continuously determined or at regular intervals. The intervals of the repeated determination and/or detection may be predetermined, for example, by the clock frequency of a processing unit.
[0021] According to one embodiment of the invention it may be provided that a control signal can be deduced for the rotary evaporator from the temporal progression of the determined temperature difference and the temporal progression of the flow rate determined. Here it is advantageous that information concerning the progression of the evaporation process and/or changes in the evaporation process can be determined and utilized.
[0022] A determination of the amount of heat accepted by the coolant as precise as possible is achieved if the cooling circuit from its input into the cooler to its outlet out of the cooler is selected as the section for the cooling spiral.
[0023] In order to support the evaporation it may be provided that during the heating process the cooler is impinged with a vacuum, particularly via a vacuum generator. A vacuum pump may be used as a vacuum generator, for example.
[0024] For an automated execution of the method it may be provided that the control signal influences at least one operating parameter of the rotary evaporator, particularly the heating performance and/or heater temperature of the heater, the pressure in the system of the rotary evaporator and/or the flow rate of the coolant. Here, it is advantageous that the method can be performed automatically with beneficial, particularly optimized operating parameters, and the operating parameters may be subsequently adjusted in an automated fashion during the progression of the method.
[0025] According to one embodiment of the invention it may be provided that the amount distilled and collected in the distillate flask is determined from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate and that the control signal causes the output of the determined value for the distilled amount.
[0026] An advantageous embodiment of the invention may provide that information is gathered from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate concerning the beginning and/or the end of the evaporation of a component of the material to be distilled, with the control signal causing the output of this information and/or the change of the heating performance of the heater and/or the pressure in the system. The invention uses the knowledge that no condensation occurs in the cooler prior to the beginning and after the end of the evaporation and thus the temperature difference at the cooling spiral is equal to zero or almost zero. Here, it is also advantageous that the rotary evaporator during operation can be protected from destruction or damage, for example during the heating of the material to be distilled due to the complete consumption of the available component of the material to be distilled provided for evaporation. Accordingly, the beginning of boiling or evaporation of unknown samples can be also determined, in particular.
[0027] Additionally, changes of the material mixture used as material to be distilled during the distillation i.e. during evaporation can be determined because these changes lead to changes in the boiling temperature and/or in the condensation energy, by which the determined temperature difference changes. This change can be evaluated and used for generating a control signal to exchange the distillate flask and/or to cancel the distillation.
[0028] In order to reach short operating times until the predetermined amount of distillate is yielded it may be provided that information is gathered from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate concerning the utilization of the cooler, with the control signal causing the output of said information and/or the control signal regulating the operating parameters of the rotary evaporator, particularly the heating performance of the heater, the pressure in the system of the rotary evaporator, and/or the flow rate of the coolant such that the utilization of the cooler is optimized, particularly that it amounts to a predetermined value and/or that the vapor is kept from reaching the vacuum generator. With the control of the temperature difference between the first and the second position in the flow path of the coolant via the pressure in the cooler and/or the temperature in the heater the distillation speed can be adjusted to the maximally possible cooling performance of the cooler, particularly in case of a predetermined flow rate of coolant. This way, a temporal optimization of the distillation is possible depending on the available cooling performance.
[0029] In one embodiment according to the invention it may be provided that during the determination of the distilled amount collected in the distillate flask the specific heat capacity of the coolant and/or the distillate, the condensation enthalpy of the distillate, and/or the effectiveness of the conversion of the condensation heat into the heating of the coolant can be considered. The method can therefore be adjusted and used for a multitude of various distillation matters and/or for a multitude of various distillation processes. Thus, a control of the distillation amount can be implemented. Due to the fact that the specific heat capacity of the coolant in the operating areas of the cooler are only slightly temperature dependent it may be considered to be constant. Temperature variations in the coolant at the inlet into the cooler have only minor effects.
[0030] A particularly simple embodiment of the method, which already shows satisfactory results for many applications, may provide that the control signal is determined from the difference of the determined temperature difference and a target temperature difference.
BRIEF DESCRIPTION OF THE DRAWING
[0031] The invention is now described in greater detail using an exemplary embodiment; however, it is not limited thereto. Additional exemplary embodiments are discernible for one trained in the art by combining the features of the exemplary embodiment with each other or with features of the claims.
[0032] FIG. 1 shows a sketch illustrating the principle of a rotary evaporator according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] A rotary evaporator, marked 1 in its entirety, has a distilling flask 4 supported rotationally around an axis 2 . The distilling flask receives a material to be distilled 3 .
[0034] A vapor tube 5 is connected to the distilling flask 4 and thus connected to its interior. This vapor tube 5 is aligned such that it encompasses the axis 2 and thus is safe from hindering the rotary motion of the distilling flask 4 .
[0035] The rotary evaporator 1 further comprises a cooler 6 . The vapor tube 5 opens at the lower end 24 of the cooler 6 in the interior chamber of the cooler 6 . A cooling spiral 8 is arranged in said interior chamber. The cooling spiral 8 is connected to the cooling circuit, not shown in greater detail, in order to form a flow path 7 . The flow path 7 is filled with a coolant, which during operation flows along the flow path 7 in order to perform cooling.
[0036] In order to collect the distillate 10 , the rotary evaporator 1 has a distillate flask 9 . The vapor tube 5 opens in a T-shaped fashion in a connection tube 22 between the interior chamber of the cooler 6 and the interior of the distillate flask 9 , by which the vapor tube 5 connects the distillation flask 4 to the cooler 6 and the distillate flask 9 .
[0037] The distillation flask 4 can be heated by a heater 11 . The heater 11 is embodied in a known fashion and heats the distillation flask 4 via a water bath.
[0038] During the heating process the distillation flask 4 is rotated by a drive 12 around the axis 2 .
[0039] The vapor 13 created by heating the material to be distilled 3 can therefore be guided through the vapor tube 5 and condensed at the cooling spiral 8 . The distillate flask 9 is arranged in a known fashion such that it can collect the condensed vapor 13 in the distillate flask 9 .
[0040] In order to determine the heating of the coolant in the cooling spiral a first temperature sensor 15 is arranged at a first position 14 in the flow path 7 of the coolant and a second temperature sensor 17 is arranged at a second position 16 in the flow path 7 of the coolant. The first location 14 is here spaced apart from the second position 16 by a section 18 of the flow path 7 of the coolant.
[0041] Means 19 are provided to determine the flow rate of the coolant through the section 18 .
[0042] In the described exemplary embodiment the first temperature sensor 15 is arranged at the cooling spiral 8 in the cooler 6 . The second temperature sensor 17 is arranged at the outlet 16 of the cooling spiral 8 from the cooler 6 . The positions of the temperature sensors are selected such that the determined temperatures correctly reflect the heating of the coolant by the condensation of the vapor 13 to the extent possible without being falsified by any influence of the environment upon the temperature of the coolant.
[0043] A flow meter 19 is arranged in the flow path 7 in order to determine the flow rate of the coolant through the section 18 of the cooling medium flow path 7 . In the exemplary embodiment, the flow meter 19 has an impeller driven by the flowing coolant and this way reflecting the flow rate.
[0044] The flow meter 19 is arranged in the flow path 7 of the coolant outside the section 18 of the flow path 7 of the coolant.
[0045] The cooler 6 is connected at its head 23 via a connection tube 21 to a vacuum generator 20 . The vacuum generator 20 impinges the interior chamber of the cooler 6 with a vacuum.
[0046] Means not shown in greater detail to determine and/or detect the temporal progression of the temperature difference between the first 15 and the second 17 temperature sensor and the temporal progression of the flow rate are embodied at the rotary evaporator 1 . These means also comprise storage means or a memory, in which the determined and/or detected temporal progressions can be saved.
[0047] Further, means not shown in greater detail are also embodied to calculate the distillate 10 collected in the distillate flask 9 within a period from the temporal progression of the determined temperature difference and from the temporal progression of the flow rate of the coolant through the section 18 of the flow path 7 of the coolant.
[0048] For this purpose, the rotary evaporator 1 comprises additional means, not shown, to input and/or store and/or select material-specific data of the material to be distilled 3 and/or the distillate 10 and/or the coolant. In particular, the specific heat capacity of the coolant and the distillate 10 , the condensation enthalpy of the distillate 10 can be predetermined and the effectiveness of the conversion of the condensation heat into the heating of the coolant can be stored.
[0049] For an automatic regulation of the evaporation process the rotary evaporator 1 comprises a control unit, by which a control signal can be deduced for the rotary evaporator 1 from the temporal progression of the temperature difference between the first 15 and the second 17 temperature signal. For this purpose, the temporal progression of the flow rate determined can be considered.
[0050] A controller is embodied at the rotary evaporator 1 to monitor the temporal progression of the determined temperature difference for temporal changes. Using this means, information can be gathered from the temporal progression of the determined temperature difference and, if applicable, the temporal progression of the determined flow rate concerning the beginning and/or the end of the evaporation of a component of the distillation matter 3 . A control signal then causes the output of said information and a change of the heating performance of the heater 11 and/or the pressure in the system.
[0051] Using the rotary evaporator 1 a method can be performed to evaporate a material to be distilled, which is explained in greater detail in the following.
[0052] The material to be distilled 3 by at least partial evaporation is inserted into the distillation flask 4 . The distillation flask 4 is supported rotationally around the axis 2 and embodied to collect the distillation matter 3 . Subsequently the distillation flask 4 with the material to be distilled 3 is heated via the heater 11 . For this purpose, the distillation flask 4 is partially immersed in the water bath of the heater 11 . The heater 11 heats the water of the water bath and regulates its temperature to a predetermined value, at which a component of the material to be distilled 3 evaporates.
[0053] During the heating process the distillation flask 4 is rotated around the electrically driven drive 12 around the axis 2 , in order to achieve an even and rapid heating. The vapor 13 forming by way of heating is guided via the vapor tube 5 encompassing the axis 2 into the cooler 6 . Instead of the vapor 13 , the term steam is also common.
[0054] The cooler 6 comprises in its interior chamber a cooling spiral 8 . The cooling spiral 8 is connected to a coolant circuit. This way, a cooling path 7 is formed for the coolant, in which coolant flows through the cooling spiral 8 .
[0055] The vapor 13 condensed at the cooling spiral 8 is collected in the distillate flask 9 .
[0056] During the process the difference of the temperatures of the coolant is continuously or in repeated intervals determined between two locations 14 , 16 in the flow path 7 of the coolant, distanced from each other by the section 18 of the flow path 7 of the coolant, and the flow rate of the coolant is determined from said section 18 on a continuous basis or in repeated intervals. The cooling spiral 8 , from its inlet 14 into the cooler 6 to its outlet 16 out of the cooler 6 , is selected as the section 18 of the coolant circuit.
[0057] During the heating process, the cooler 6 and the entire distillation system is impinged with a vacuum from the vacuum generator 20 .
[0058] A control signal is deduced for the rotary evaporator 1 from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate. Said control signal comprises several information units and is transferred as a multi-component signal serially via at least one communications channel or parallel via several communications channels.
[0059] This control signal influences an operating parameter of the rotary evaporator 1 , for example the heating power of the heater 11 , the pressure in the cooler 6 , and/or the flow rate of the coolant.
[0060] The distilled amount, collected in the distillate flask 9 , is determined from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate. The control signal results in an output of the determined value for the distilled amount.
[0061] Further, information is gathered concerning the beginning and/or the end of the evaporation of a component of the material to be distilled 3 from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate. The control signal causes the output of said information on a display. The control signal also causes the change of the heating power of the heater 11 . This way, the heating power, particularly the operating temperature of the water bath or the heater 11 and/or the pressure in the system are adjusted to the evaporating temperature of the component to be evaporated.
[0062] Information is gathered from the temporal progression of the determined temperature difference and the temporal progression of the determined flow rate about the utilization of the cooler 6 . The control signal causes the output of said information. The control signal controls the operating parameters of the rotary evaporator 1 , particularly the heating power of the heater 11 , the pressure in the system of the rotary evaporator 1 , and/or the flow rate of the coolant such that the utilization of the cooler 6 is optimized. Here, the temperature difference at the cooling spiral 8 is monitored and the operating parameters are modified such that vapors are condensed only over a length of approximately 80%, i.e. from 70% to 90% or from 75% to 85% or precisely 80% of the length of the cooling spiral 8 , measured prior to entering the cooler 6 . The temperature difference equivalent to this utilization of the cooler 6 is determined for the rotary evaporator 1 prior to operation by way of experiments and stored in the control. These tests occur by varying the operating parameters under the visual control of the condensation processes at the cooling spiral 8 , particularly the size of the section of the cooling spiral 8 , at which vapor 13 condenses. By the adjustment to the predetermined value it is achieved that the vapor 13 is prevented from entering the vacuum generator 20 . It is known that above a certain temperature difference at the cooling spiral 8 , depending on operating parameters of the rotary evaporator 1 , particularly the cooler 6 , a quantitative condensation of the distillate 10 is no longer possible. When the cooler 6 is overstrained in its performance in this way, vapor 13 exits the cooler 6 and is lost from the process.
[0063] When determining the amount of matter distilled and collected in the distillate flask 9 the specific heat capacity of the coolant and the distillate 10 , the condensation enthalpy of the distillate 10 , and the effectiveness of the conversion of the condensation heat into heating the coolant are considered. From the temperature difference determined at the cooling spiral 8 and using the knowledge of the flow rate through the cooling spiral 8 the heat amount accepted by the coolant per time unit is determined. This is equivalent to the heat amount emitted during condensation of the vapor 13 . This way, the amount of condensed distillate 10 can be calculated from the condensation enthalpy of the distillate 10 and the calculated heat amount. For many materials, instead of the exact specific values, preset standard values may also be used.
[0064] The control and monitoring of the utilization of the cooler 8 calculates the difference Z=X−Y of the determined temperature difference X at the cooling spiral 8 and a target-temperature difference Y and uses Z as the variable.
[0065] At the starting point of the distillation the actual value X of the temperature difference at the cooling spiral 8 is almost zero because no vapor 13 condenses at the cooling spiral 8 . Now, a target value Y is selected for the temperature difference. The heating power in the heater 11 and/or the pressure in the system is adjusted to the predetermined target-temperature difference Y. This way, the desired amount of distillate is produced.
[0066] In the rotary evaporator 1 with a cooler 6 , temperature sensors 15 , 17 are arranged in the inlet 14 and the outlet 16 of the coolant into and/or out of the cooler 6 , and the flow rate of the coolant through the cooler 6 is determined. The beginning and/or the end of the condensation in the cooler 6 is deduced from the increase and/or reduction of the difference of the temperatures X at the temperature sensors 15 , 17 . The amount of the condensed distillate 10 is determined from the difference of the temperatures X and a control of the distillation amount is performed. The utilization of the cooler 6 is controlled by controlling the heating power of the heater 11 and/or the pressure in the system depending on the difference of the temperatures X. | A rotary evaporator ( 1 ) having a cooler ( 6 ), wherein temperature sensors ( 15, 17 ) are disposed in the inlet ( 14 ) and outlet ( 16 ) of the coolant into or out of the cooler ( 6 ), and a volume flow rate of the coolant through the cooler ( 6 ) is determined. The initiation or termination of condensation in the cooler ( 6 ) is derived from an increase or decrease in the difference of the temperatures (X) at the temperature sensors ( 15, 17 ). The volume of the condensed distillate ( 10 ) is determined from the difference in temperatures (X), and a distillation volume control is performed. By regulating the heating power of the heater ( 11 ) and/or the pressure in the system, the loading of the cooler ( 6 ) is controlled as a function of the difference in temperatures (X). | 1 |
BACKGROUND OF THE INVENTION
This invention relates to the field of borehole measurement while drilling (MWD). More particularly, this invention relates to the communication of control information from the drilling rig floor to the MWD instrumentation system when it is situated downhole near the bottom of the drill string.
An MWD system may consist of a number of sensors connected to a computer based data acquisition system. The computer collects the information from the sensors and digitizes and formats this information for downhole storage and for binary data transmission to the surface. Relevant parameters of the data collection and formatting process are stored according to preprogrammed instructions residing in the computer's memory.
Current state of the art of MWD data transmission is via mud pulse telemetry. Data communication rates achievable with this technology is on the order of one bit per second. As the number of sensors developed for downhole application increases, the time required to transmit all the data increases. Further, information update requirements of certain parameters may vary depending on conditions arising during the course of drilling. Unfortunately, there is not now an efficient and reliable method of relaying control information from the drill rig at the surface downhole to the MWD system so as to effect a change in operation of the system (e.g. an operational mode change). Presently, the MWD system must be raised to the surface where operational changes are input to the computer. Thus, it would be advantageous to be able to alter the operating modes of the MWD system without removing it from the borehole. Affecting a change without removal would save a substantial amount of time in the drilling process and therefore afford considerable cost savings.
SUMMARY OF THE INVENTION
The above-discusses and other problems and deficiencies of the prior art are overcome or alleviated by the method and apparatus of the present invention for establishing a remote communications link from the rig floor (e.g. well platform) to the downhole MWD system. In accordance with the present invention, the state of a physical condition downhole is changed in a predetermined timed sequence. This state change is controlled on the surface at the drilling platform and simultaneously detected or measured downhole by the MWD system. The desired operating mode of the MWD system is then determined based on the detected time sequence of the state changes.
Preferred embodiments of the present invention utilize two different state changes which are detectable downhole and which can be controlled at the surface. In a first embodiment, the state changes comprise a preselected timed sequence of powering the MWD system up or down. This power cycling is accomplished by operating the mud pump in an ON/OFF sequence which will cause the MWD turbine to similarly be powered up or down.
In a second embodiment of the present invention, the state changes are accomplished by modulating the mud flow in a timed sequence which will result in modulations to the MWD turbine. Preselected modulations in the turbine will result in a pattern of power modulations in the MWD systems which will trigger a different operating mode.
The above-discussed and other features and advantages of the present invention will be appreciated and understood by those of ordinary skill in the art from the following detailed description ad drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, wherein like elements are numbered alike in the several FIGURES:
FIG. 1 is a generalized schematic view of a borehole and drilling derrick showing the environment for the present invention;
FIG. 2 is a front elevation view, partly in cross section, of a borehole measurement-while-drilling (MWD) system;
FIG. 3 is a state diagram for transitions in an operating mode for of the present invention;
FIG. 4 is a state diagram for transitions between operating modes for of the present invention;
FIG. 5 is a circuit diagram of a time lapse detection circuit used in the present invention;
FIG. 6 is a flowchart for of the present invention; and
FIG. 7 is a block diagram of an MWD system in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIGS. 1 and 2, the general environment is shown in which the present invention is employed. It will, however, be understood that these generalized shownings are only for purposes of showing a representative environment in which the present invention may be used, and there is no intention to limit applicability of the present invention to the specific configuration of FIGS. 1 and 2.
The drilling apparatus shown in FIG. 1 has a derrick 10 which supports a drill string or drill stem 12 which terminates in a drill bit 14. As is well known in the art, the entire drill string may rotate, or the drill string may be maintained stationary and only the drill bit is rotated. The drill string 12 is made up of a series of interconnected segments, with new segments being added as the depth of the well increases. In systems where the drill bit turbine driven, it is often desirable to slowly rotate the drill string. That can be accomplished by reactive torque from the drilling, or by actual rotation of the drill string from the surface. To that latter end, the drill string is suspended from a movable block 16 of a winch 18, and the entire drill string may be driven in rotation by a square kelly 20 which slidably passes through but is rotatably driven by the rotary table 22 at the foot of the derrick. A motor assembly 24 is connected to both operate winch 18 and rotatably drive rotary table 22.
The lower part of the drill string may contain one or more segments 26 of larger diameter than other segments of the drill string known as drill collars. As is well known in the art, these drill collars may contain sensors and electronic circuitry for sensors, and power sources, such as mud driven turbines which drive drill bits and/or generators and, to supply the electrical energy for the sensing elements.
Drill cuttings produced by the operation of drill bit 14 are carried away by a large mud stream rising up through the free annular space 28 between the drill string and the wall 30 of the well. That mud is delivered via a pipe 32 to a filtering and decanting system, schematically shown as tank 34. The filtered mud is then sucked by a pump 36, provided with a pulsation absorber 38, and is delivered via line 40 under pressure to a revolving injector head 42 and then to the interior of drill string 12 to be delivered to drill bit 14 and the mud turbine if a mud turbine is included in the system.
The mud column in drill string 12 also serves as the transmission medium for carrying signals of downhole parameters to the surface. This signal transmission is accomplished by the well known technique of mud pulse generation whereby pressure pulses are generated in the mud column in drill string 12 representative of sensed parameters down the well. The drilling parameters are sensed in a sensor unit 44 (see FIG. 2) in a drill collar 26 near or adjacent to the drill bit. Pressure pulses are established in the mud stream within drill string 12, and these pressure pulses are received by a pressure transducer 46 and then transmitted to a signal receiving unit 48 which may record, display and/or perform computations on the signals to provide information of various conditions down the well.
Referring briefly to FIG. 2, a schematic system is shown of a drill string segment 26 in which the mud pulses are generated. The mud flows through a variable flow orifice 50 and is delivered to drive a first turbine 52. The first turbine powers a generator 54 which delivers electrical power to the sensors in sensor unit 44 (via electrical lines 55). The output from sensor unit 44, which may be in the form of electrical, hydraulic or similar signals, operates a plunger 56 having a valve driver 57 which may be hydraulically or electrically operated. Variations in the size of orifice 50 create pressure pulses in the mud stream which are transmitted to and sensed at the surface to provide indications of various conditions sensed by sensor unit 44. This mud pulse transmitter is more fully shown and described in U.S. Pat. Nos. 3,982,431, 4,013,945 and 4,021,774 assigned to the assignee hereof. Mud flow is indicated by the arrows.
Since sensors in sensor unit 44 are magnetically sensitive, the particular drill string segment 26 which houses the sensor elements must be a non-magnetic section of the drill string, preferably of stainless steel or monel. Sensor unit 44 is further encased within a non-magnetic pressure vessel 60 to protect and isolate the sensor unit from the pressure in the well.
While sensor unit 44 may contain other sensors for directional or other measurement, it will contain a triaxial magnetometer with three windings, those windings being shown separately, merely for purposes of illustration and description, as windings 56A, 56B, and 56C, being respectively the "x", "y" and "z" magnetometer windings.
Turning now to FIGS. 3-7, a first embodiment of the present invention will now be discussed. As mentioned, the present invention utilizes a predetermined timed sequence of state changes of a physical condition downhole to communicate or transmit information from the well platform downhole. The changes in the physical condition are controlled at the surface preferably to effect a change in operation of the MWD system (usually a MWD system software change). A important feature of the first embodiment is that of measuring the time between successive power up cycles of the MWD system. When the criteria of not exceeding maximum power down time is met for some minimum number of repetitions, the MWD system software changes the operating mode of the MWD system and resets the cycle counter. In accordance with the present invention, such power up cycling can be accomplished by successively starting and stopping mud flow from the pump 36 through the interior of the drill string 12 and hence through MWD turbine 52.
Preferably, the method of the first embodiment incorporates protection from inadvertant operating system mode changes by requiring successive events. Failure to meet the maximum "time on" or "time off" criteria the requisite number of times immediately resets the cycle counter without changing the system's operating mode.
An example of a sequence to change the operating mode can be depicted in a state diagram as shown in FIG. 3. Each state is an increment in the cycle counter. Each circle represents a possible path between operating states. The arrows indicate the direction in which the transitions from one state to another can occur. The letters associated with each line indicate the condition which forces the transition. The diagram further shows the sequential conditions that must be met to select any mode. The number of cycles required to change modes in this diagram could be increased or decreased to trade off the likelihood of inadvertent mode change with the time required to force such a change. Thus, in FIG. 3, a sequence of four (4) ON/OFF cycles corresponding to the timing of B is needed to move through the states identified at "0", "1", "2" and "3" and thereby change the MWD system from operating mode N-1 to operating mode N+1. If at any time during that ON/OFF sequence, either of the timing transitions of A or C occur, then the cycle counter is reset to the "0" state.
The cycle count is updated and stored in non volatile read/write memory such as EEPROM (see item 83 in FIG. 7). The transitions between system modes is shown in FIG. 4. The transitions occur in circular fashion. Any number of modes is possible. The trade off is that the greater the number of modes, the longer the potential time required to switch between two non adjacent modes. It will be appreciated that for each mode transition, e.g. mode 1 to mode 2, the timed sequence transition criteria of FIG. 3 must be complied with or no mode change will take place.
The first embodiment of this invention consists of three elements added to a conventional MWD system to form a complete MWD system having reprogramming capability (as shown in FIG. 7). These elements are:
1. A means of establishing the time lapse between MWD system power down and subsequent power up (FIG. 5).
2. Software to implement the state machines shown in FIGS. 3 and 4.
3. Some form of non volatile memory to retain the state machine states while the system is unpowered (due to the absense of mud flow).
One means of detecting time lapse is shown in FIG. 5. The circuit shown receives three inputs from the MWD system and provides one output back to the MWD system. The inputs consist of +5 volt power, the "charge" control signal, and the RESET signal The +5 volt power buss is activated by mud flow driving the MWD system turbine. This power buss is used to power various MWD system elements including its computer. Since this Power buss is already present in the system, it is used in this circuit as a power source for circuit elements U1 and U2, a source to charge energy storage capacitor C2, a source to generate the reference voltage Vr via the resistor divider network formed by resistors R2 and R3, and a source to charge timing capacitor C1 when switches S1 and S2 are closed.
The RESET signal is used to initialize the MWD system during power up and Prevent erratic behavior during power down. This signal is asserted (logic zero) and maintained whenever +5 volt is out of tolerance (below the minimum level required to guarantee proper function of the computer system). This signal is used advantageously by the circuit of FIG. 5 to disconnect the subcircuit composed of the parallel combination of R1 and C1 from the rest of the circuit when mud flow is interrupted. When 5 volts is within tolerance, reset will go to a logic one, closing S2. The voltage of capacitor C1 (Vc1) can now be compared against reference voltage Vr by comparator U2.
The output of the comparator is detected by the computer as a logic one or a logic zero. A logic one implies that Vc is greater than Vr, which in turn implies that Toff is less than Toff (max) as shown in the state diagram of FIG. 3.
Having detected whether Toff is less than Toff (max) is true or false, the computer can assert the "charge" signal. This closes S1 and allows C1 to be recharged for the next part of the reprogramming sequence. Note S2 was already closed by RESET.
Capacitor C1 will charge to about 4.5 volts and stay there as long as +5 volt power is applied. Diode D1 accounts for the approximately 0.5 volt drop from 5 volts. Capacitor C2 is charged to 4.5 volts through Diode D1 immediately as +5 volts is asserted.
C2 is sized so that during power down its voltage will decay more slowly than that on C1. With U1 thus powered, the C1 R1 network is kept isolated during power down.
Vr is established by R2 and R3 to be 0.5 volts. From this, the values of R1 and C1, and the initial voltage of C1, the value of Toff (max) can be established as:
Toff (max)=R1 C1 1n (4.5 V)/(0.5 V)=44 seconds
It is understood that Toff (max) could be adjusted by varying any of the influencing parameters.
A flowchart of the software necessary to implement the state machines of FIGS. 3 and 4 is shown in FIG. 6.
The "start power on timer" block implies the existence of a real time clock in the MWD computer system. Its implementation is well understood by anyone familiar with the state of the art. The clock is needed to establish if the "C" transition of FIG. 3 must be carried out.
Executing of the "Toff is less than Toff (max)" decision block requires reading the input port to which the output of U2 of FIG. 5 is connected. A logic one forces the "yes" branch and vice versa.
The "increment cycle counter" block requires reading a non volatile memory location containing the current count, adding one, and writing the new count back into the same location. Implementing non volatile read/write memory using EEPROM memory technology or battery backed RAM is well understood and is shown in FIG. 7 at items 83 and 98, respectively, which will now be discussed.
The method of the present invention is intended to be implemented in conjunction with the normal commercial operation of a known MWD system and apparatus of Teleco Oilfield Services Inc. (the assignee hereof) which has been in commercial operation for several years. The known system is offered by Teleco as its CDS (Computerized Directional System) for MWD measurement; and the system includes, inter alia, a triaxial magnetometer, a triaxial accelerometer, control, sensing and processing electronics, and mud pulse telemetry apparatus, all of which are located downhole in a rotatable drill collar segment of the drill string. The known apparatus is capable of sensing the components Gx, Gy, and Gz of the total gravity field Go; the components Hx, Hy, and Hz of the total magnetic field Ho; and determining the tool face angle and dip angle (the angle between the horizontal and the direction of the magnetic field).
Referring to FIG. 7, a block diagram of the known CDS system of Teleco is shown. This CDS system is located downhoIe in the drill string in a drill collar near the drill bit. This CDS system includes a 3-axis accelerometer 70 and a 3-axis magnetometer 72. The x axis of each of the accelerometer and the magnetometer is on the axis of the drill string. To briefly and generally describe the operation of this system, accelerometer 70 senses the Gx, Gy, and Gz components of the downhole gravity field Go and delivers analog signals commensurate therewith to a multiplexer 74. Similarly, magnetometer 72 senses the Hx, Hy, and Hz components of the downhole magnetic field. A temperature sensor 76 senses the downhole temperature compensating signal to multiplexer 74. The system also has a programmed microprocessor unit 78, system clocks 80 and a peripheral interface adapter 82. All control, calculation programs and sensor calibration data are stored in EEPROM Memory 83.
Under the control of microprocessor 78, the analog signals to multiplexer 74 are multiplexed to the analog-to-digital converter 84. The output digital data words from A/D converter 84 are then routed via peripheral interface adapter 82 to microprocessor 78 where they are stored in a random access memory(RAM) 86 for the calculation operations. An arithmetic processing unit (APU) 88 provides off line high performance arithmetic and a variety of trigonometry operations to enhance the power and speed of data processing. The digital data for each of Gx, Gy, Gz, Hx, Hy, Hz are averaged in arithmetic processor unit 84 and the data are used to calculate azimuth and inclination angles in microprocessor 78. These angle data are then delivered via delay circuitry 90 to operate a current driver 92 which, in turn, operates a mud pulse transmitter such as was described above.
In accordance with the present invention and as discussed above, the time lapse detection circuit of FIG. 5 is shown at 96, and a battery for RAM 86 is shown at 98.
In a second embodiment of the present invention, the operating mode of the MWD system is changed by a timed sequence of changes in the amount of power generated by the MWD turbine. In other words, rather than the power being turned on and off as in the first embodiment, the second embodiment of this invention calls for modulating the amount of power sent to the MWD system in a timed sequence to move from one operating mode to another. This modulation is accomplished by modulating the mud flow from the mud pump at the drill rig surface through the MWD turbine. This second embodiment may be carried out using a method and apparatus similar to that described with regard to the first embodiment.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. | A method and apparatus for establishing a remote communications link from the rig floor to the downhole MWD system is presented. In accordance with the present invention, the state of a physical condition downhole is changed in a predetermined timed sequence. This state change is controlled on the surface at the drilling platform and detected downhole by the MWD system. The desired operating mode of the MWD system is then determined based on the detected time sequence of the state changes. Preferred embodiments of the present invention utilize two different state changes which are detectable downhole and which can be controlled at the surface. In a first embodiment, the state changes comprise a preselected timed sequence of powering the MWD system up or down. This power cycling is accomplished by operating the mud pump in an ON/OFF sequence which will cause the MWD turbine to similarly be powered up or down. In a second embodiment of the present invention, the state changes are accomplished by modulating the mud flow in a timed sequence which will result in modulations to the MWD turbine. Preselected modulations in the turbine will result in a pattern of power modulations in the MWD systems which will trigger a different operating mode. | 4 |
BACKGROUND OF THE INVENTION
The invention relates to a cost efficient and flexible injection molding apparatus, especially an apparatus for the manufacture of discs, such as optical discs, compact discs, video discs or the like.
The mass production of discs, such as optical recording discs or audio CD's, is performed on single cavity injection molding machines linked with secondary processing equipment for metalizing, decorating, lacquering and inspecting the molded articles. Typically, production cells are arranged in a "clean room" environment with each unit acting independently of the next. The handling of tooling for program changes and the finished product is not coordinated or performed automatically from one machine to the next. A typical factory layout may use two molding machines feeding parts to downstream processing equipment via a conventional conveyor.
Alternatively, one may employ two separate vertical clamping injection molding units with single cavity molds to produce the discs. Each unit may employ a dedicated robot to unload the produced parts and place them on a conveyor which carries the parts to the processing equipment for further processing, e.g., sputtering (metalizing), bonding and inspection. Each station may have means to store a limited number of discs to act as a buffer between operators.
It is desirable to provide means for automatically changing the stamper and also for automatically handling the stamper once removed from the mold.
U.S. Pat. No. 4,917,833 to Cools shows a conventional single cavity CD mold with a means to speed up stamper changing by using a quick release lock ring that can be used by the operator to handle the stamper. U.S. Pat. No. 4,971,548 to Asai shows a two cavity disc mold having a quick removable pack for stamper changing; however, similar to the '833 patent the operator is required to handle the unit during the process. U.S. Pat. No. 5,401,158 to Kubota et al. shows another stamper changing unit that automatically loads and unloads stampers from the mold, but requires subsequent manual transport from the changing unit.
European Patent 0605025 to Becker et al. shows a two cavity disc mold in a single horizontal clamping machine having individual injection units, one for each mold, and a robot to unload both produced parts simultaneously. U.S. Pat. No. 4,981,634 to Maus et al. shows a method for unloading the molded parts that does not require opening the mold, and U.S. Pat. No. 5,192,474 to Eichlseder et al. shows removing the molded parts by using part of the mold as the carrier.
In all cases where automatic removal of molded parts is shown, one robot per machine/mold is employed in which the robot remains idle most of the time. This represents an inefficient utilization of the robot which does not optimize its cost.
U.S. Pat. No. 3,196,485 to Battenfeld et al. and U.S. Pat. No. 4,427,353 to Omiya et al. both show vertical clamping, single cavity disc molding machines. The '485 patent teaches a compression process with resin being delivered from a horizontal unit directly into the open mold, whereas the '353 patent shows another compression unit with the resin delivered from a reciprocating injection unit mounted vertically and coaxial with the vertically acting clamp.
There is a rapidly rising demand for optical disc production for audio CD, CD-Rom and DVD applications. To meet this demand there is a need for a cost efficient, flexible manufacturing cell configuration that can be integrated into a complete factory operation so that automation of the apparatus and process can be maximized and resources optimized.
Accordingly, it is a principal object of the present invention to provide an improved injection molding apparatus and process that is cost efficient and flexible.
It is a further object of the present invention to provide an apparatus and process as aforesaid that is operative to prepare molded discs and automatically exchanges stamper units with a minimum of disruption.
Further objects and advantages of the present invention will appear hereinbelow.
SUMMARY OF THE INVENTION
In accordance with the present invention, the foregoing objects and advantages are readily obtained.
The injection molding apparatus of the present invention comprises: at least a first and second injection molding machine adjacent one another, with each machine including fixed and movable mold elements operative to form molded products, and robot means adjacent said injection molding machines operative to remove and replace at least a portion of one of said mold elements from a first of said injection molding machines while the second of said injection molding machines continues to form molded products. Preferably the molded products are discs and the mold elements include a stamper unit, with the robot means being operative to remove and replace a stamper unit from the first injection molding machine while the second injection molding machine continues to form discs. The apparatus is operative to sequentially remove and replace a stamper unit from the first and second injection molding machine while the other machine continues to form discs.
In accordance with the present invention, one robot is used to unload the molded parts from both injection molding machines. In addition, the automatic stamper change robot conveys the stampers to and from a storage area where the stampers are prepared, and an automatic control system controls which stamper is loaded into which machine at what time to produce a specified number of molded articles, thereby providing an automated production factory system.
The process of the present invention provides at least a first and second injection molding machine adjacent one another, with each machine including fixed and movable mold elements operative to form molded products, with the molded products preferably being discs and the mold elements preferably including a stamper unit. The process of the present invention removes and replaces at least a portion of one of the mold elements, as a stamper unit, from a first of the injection molding machines by a robot means while the second of the injection molding machines continues to form molded products.
Further features of the apparatus and process of the present invention will appear hereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more readily understandable from a consideration of the following exemplificative drawings, wherein:
FIG. 1 is a side view of an injection molding apparatus of the present invention;
FIG. 2 is a front view of the apparatus of FIG. 1;
FIG. 3 is a plan view of the apparatus of FIG. 1 showing two side-by-side injection molding machines;
FIG. 4 is a plan view of a disc manufacturing cell using the injection molding apparatus of the present invention;
FIG. 5 is a side view of the disc manufacturing cell of FIG. 4;
FIG. 6 is a plan view of a disc manufacturing layout using the injection molding apparatus of the present invention; and
FIGS. 7-10 are detailed plan views of a stamper change unit showing, respectively, removal, mold cleaning, selection of new stamper, and loading new stamper.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIGS. 1, 2 and 3, a two station, vertically clamping disc injection molding machine is shown comprising two side-by-side vertical clamp units, namely, a first injection molding machine 10 and an adjacent second injection molding machine 12. The discs can be any desired disc, as optical discs, compact discs, video discs or the like. Each injection molding machine includes a fixed platen 14, a movable platen 16, a plurality of tiebars 18 as for example three tiebars in this embodiment, and motive means 20 to move the movable platen 16 on the tiebars 18 to the closed position shown in FIG. 2 for machine 10 and to the open position shown in FIG. 2 for machine 12.
Molds 22 including mold halves 24 and 26 are positioned between platens 14 and 16, with mold half 24 fixed to stationary platen 14 and mold half 26 fixed to movable platen 16. Therefore, movement of platen 16 via motive means 20 from the open to closed position moves mold half 26 to the closed position and closes mold 22.
A first mode of movement is during the injection molding of discs in mold 22. This mode of movement requires that mold half 26 be moved into the closed position as shown in FIG. 1 and in FIG. 2 for machine 10. In addition, the injection molding mode requires that movable platen 16 open mold 22 sufficiently to allow disc removal robot 28 to enter space 30 between open mold halves 24 and 26 and remove the molded disc 32 as shown in FIG. 3. This is called the first open position and consists of opening the mold only far enough for the part removal robot 28 to enter and remove the molded part, for example, about two inches, as shown in FIG. 3. Note that a single disc removal robot 28 is positioned adjacent machines 10 and 12 and serves to unload both of the side-by-side injection molding machines.
The second mode of movement requires movable platen 16 to open a distance wider than the first open position, with the second open position shown in FIG. 2 for machine 12, in order to permit the removal of a stamper unit or complete movable mold half by a second robot, as will be discussed hereinbelow. Thus, the second open position shown in FIG. 2 for machine 12 is the open position for changing the stamper because the stamper change robot needs more room, for example, about 12 inches. The opening mechanism 20 may consist of two elements. The first is a motor driven screw system for moving the movable platen to its furthest open position. This position is only used for stamper change and may not happen frequently, as for example once per hour; whereas opening the mold from the closed position to the first open position for part removal occurs for example once every 3.5 seconds. The mechanism for doing the motion to the first open position is a clamping piston (not shown) mounted underneath the movable platen and on top of the screw drive means. Thus, the two inch opening stroke is done with a hydraulic piston which also serves as the clamp piston and the 12 inch stroke is done with screw actuated drive means. Motive means 20 may be used for both the first and second modes of movement, or if desired a separate motive means may be used for these two modes of movement in order to allow optimization of energy consumption and cost of machine construction.
The two injection molding machines 10 and 12 are mounted on a common machine base 34, which also supports the machine services, such as hydraulic pump, motor, and tank and associated valving and controls shown schematically by unit 36.
Each machine 10 and 12 has an associated resin injection unit 38 and 40 mounted on top of their respective fixed platens. These may be conventional reciprocating screw units that are well known in the art and in this embodiment are adopted for vertical operation. Each resin injection unit may be mounted to permit vertical carriage travel in order to provide for separation of units 38 and 40 from machines 10 and 12 and to allow the units to be swung sideways as shown in phantom at 42 for unit 40 for purging or maintenance. The hydraulic power supply and control for both injection units 38 and 40 may be provided by the single set of machine services in unit 36, thereby optimizing energy efficiency while minimizing construction cost.
In operation, each machine 10 and 12 can operate independently or in synchronism with its side-by-side twin as required. Thus, while one machine is stopped for a stamper change or repair, the other machine can continue production without interruption. When both machines are in production, their cycles can be synchronized such that the single disc removal robot 28 can unload each machine sequentially, thereby optimizing the utilization of robot 28. Robot 28 discharges molded discs 32 from machines 10 and 12 onto a single conveyor 44 to transport the discs to the next stage of manufacturing.
A conventional metalizing (sputtering), bonding, decorating, lacquering and inspection unit 46 is used to complete the manufacturing process for the discs. One of units 46 can typically handle the output rate of two single cavity molding machines; however, in this case one unit is shown linked to a plurality, i.e., four, molding machines. With the advent of DVD production (video discs) the injection molding units may produce two halves of a single disc, which the downstream unit 46 will bond or weld into a single disc assembly. Thus, four injection molding units to maintain a high production rate.
FIG. 5 is a side view of a manufacturing cell of the present invention showing the downstream processing unit 46 and conveyor 44.
FIGS. 7-10 show a mold or mold stamper change robot 48 adjacent machines 10 and 12 and aligned with machine 10. Robot 48 is aligned with machine 10 in the second operating mode wherein the movable platen 16 and mold half 26 is opened to its furthest position spaced from fixed platen 14 and mold half 24. The robot 48 removes the used stamper 50 (or complete mold half), cleans the mold, and installs a new stamper 52 (or complete mold half) is installed, while machine 12 continues its operation uninterrupted. FIG. 7 shows robot 48 arm 54 first end 55 thereof removing used stamper 50 from machine 10. FIG. 8 shows arm 54 rotated 180° in the direction of arrow A from the position in FIG. 7, used stamper 50 is deposited, robot arm 54 has translated to move robot arm second end 56 into the mold area, and mold half 26 being cleaned by robot arm 54 second end 56 opposed to first end 55. FIG. 9 shows robot arm 54 moved axially to pick up new stamper 52 on robot 54 first end 55. FIG. 10 shows robot 54 returned to the position of FIGS. 7 and 8 and rotated 180° in the direction of arrow A to place new stamper 52 in mold 10.
After the replacement operation is completed, robot 48 disengages from machine 10 and the molding cycle of machine 10 is automatically resumed using the new stamper unit 52. Thus, in accordance with the present invention, changing the program material of the discs as well as cleaning the mold can be accomplished fully automatically and rapidly, with typical stamper change time being less than a few minutes.
A typical factory layout is shown in FIG. 6 wherein a plurality of first and second injection molding machines are provided with a single robot means utilized to remove and replace stamper units (or molds) from all of them. Thus, machines 10 and 12 are shown as well as further machines 57 and 58 and 60 and 62, all adjacent each other. Still more of the machines can be provided, all serviced by a single robot means 48, but for simplicity only three sets have been shown. All machines are essentially the same with all operative to prepare injection molded discs.
Thus, each manufacturing cell comprises two injection molding machines, i.e., cell 64 includes machines 10 and 12, cell 66 includes machines 57 and 58 and cell 68 includes machines 60 and 62. Each cell has two molds, conveyors and downstream processing unit in a line such that track 70 may be mounted to the base of each of the molding machines. Robot 48 travels along track 70 and is able to service any of the molds in the row. The robot travel envelope may be shielded from personnel by a barrier 71 and access for servicing machines may be provided from the non-robot side of the track. Each molding unit is capable of being fully serviced without interruption and without interrupting the ability of robot 48 to continue servicing the other units that are in production.
Factory control system 72 located in or adjacent clean room 74 on track 70 controls which program stampers 52 are loaded and unloaded into which molding units via robot means 48. The clean room is simply a closed environment maintained free of dust and other pollutants and maintained as clean as feasible. FIG. 6 shows a robot means 48 adjacent cell 66 and a robot means 48 in clean room 74, whereas in practice only a single robot means would shuttle between the clean room and the various cells. Thus, robot means 48 returns used stampers 50 to clean room 74 and picks up new stampers 52 from carousel 76. Operators in the clean room prepare the new stampers and refurbish used ones as required by the production plan. Thus, unattended operation can be achieved when sufficient prepared stampers are loaded onto carousel 76 and the production control system 72 has been programmed to cause a predetermined number of discs to be manufactured with a predetermined variety of program material. Control system 72 also controls each of the injection molding machines and downstream processing units 46 in order to completely coordinate and synchronize the manufacturing program.
Obviously, other specific configurations of plant layout can be configured depending on the size of building or space available and the planned production capacity. However, in all cases, using the features of the present invention provides opportunities for optimizing factory floor space, energy personnel, production, machinery costs, etc. in order to obtain a specified production rate of finished discs.
It is to be understood that the invention is not limited to the illustrations described and shown herein, which are deemed to be merely illustrative of the best modes of carrying out the invention, and which are susceptible of modification of form, size, arrangement of parts and details of operation. The invention rather is intended to encompass all such modifications which are within its spirit and scope as defined by the claims. | The invention covers an injection molding apparatus and injection molding process. The apparatus has at least a first and second injection molding machine adjacent one another, with each machine including upper and lower mold elements operative to form molded products; and robot adjacent said injection molding machines operative to remove and replace at least a portion of one of said mold elements from a first of said injection molding machines while the second of said injection molding machines continues to form molded products. | 8 |
This application is based on Patent Application No. 2001-024553 filed Jan. 31, 2001 in Japan, the content of which is incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a printing apparatus and method for a printer, a copy machine, a facsimile terminal equipment, or the like, and specifically, to correction of the deviation of a printed position resulting from an error in transportation of a printing sheet.
2. Description of the Related Art
Conventional printing apparatuses such as printers, copy machines, and facsimile terminal equipment are equipped with a mechanism which transports a printing sheet as a printing medium. The mechanism includes a transportation roller, a pinch roller pressing the printing sheet against the transportation roller and holding the printing sheet between the pinch roller and the transportation roller, a device for causing the pinch roller to apply pressing force on the printing sheet, and other devices. Such transportation mechanism executes transporting operation for the printing sheet fed by a sheet feeding section, in a printing area by a printing head, and two pairs of such transportation mechanisms are generally provided before and behind the printing area, respectively. Thus, the printing sheet is precisely transported in the printing area, and during the transportation, predetermined tension is applied to the printing sheet to keep it flat over a wide area.
FIG. 11 is a sectional view mainly showing the transporting mechanism for the printing sheet in a conventional example of a printing apparatus based on an ink jet method.
In the figure, a printing head 7 mounted in a carriage portion 5 executes a scanning operation in a direction perpendicular to the drawing sheet, and during the scanning operation, ejects ink for performing a printing operation. In relation to the printing area covered by the printing head, a printing sheet P is transported, under the carriage portion 5 , from right to left in the figure with substantially keeping its horizontal position. More specifically, as the above-stated two pairs of transportation mechanisms, a pair of a transportation roller (hereinafter referred to as “LF roller”) 36 and a pinch roller 37 is provided in an upstream side of the printing area, in which the printing sheet is transported, and a pair of a sheet discharging roller 41 and a spur 42 is provided in a downstream side of the printing area. Among these rollers, the pinch roller 37 is rotatably supported on a rotation shaft provided in a pinch roller holder 30 . The pinch roller holder 30 is urged by a pinch roller spring 31 so that the pinch roller 37 can be pressed against the transportation roller 36 . A pressing mechanism (not shown) similarly applies pressing force which is applied between the sheet discharging roller 41 and the spur 42 . The two pairs of rollers respectively hold the printing sheet P therebetween, and a driving mechanism (not shown) rotationally drives the transportation roller 36 and the sheet discharging roller 41 , thereby causing the printing sheet P to be transported a predetermined distance for each one scanning operation of the printing head.
However, it is known that the above-described transportation mechanism may cause a deviation of transporting position of the printing sheet: when the printing sheet P is transported and a back end thereof slips out from the transportation roller 36 and the pinch roller 37 holding the printing sheet therebetween, the printing sheet P may be transported more than a expected predetermined distance, thereby a relative position of the printing head to the printing sheet P deviating from the regular one. As a result, a position (position of an printed image) of an ink dot formed on the printing sheet P with ink ejected from the printing head deviates from a standard position, thereby degrading the printed image.
FIGS. 12A and 12B show a positional relationship between the transportation roller 36 and the pinch roller 37 . As shown in FIG. 12B , the transportation roller 36 has a length corresponding to a width of the printing sheet P. On the other hand, a plurality of pinch rollers 37 , each of which is shorter than the transportation roller 36 , are disposed correspondingly to the transportation roller. With this configuration, when the back end of the printing sheet P slips out from the transportation roller 36 and the pinch rollers 37 , the pinch rollers 37 move toward the transportation roller a distance corresponding to a thickness of the printing sheet P, which has been held by the pinch rollers 37 and the transportation roller 37 between there. Urging force of the pinch roller 37 associated with this movement causes the printing sheet P to be transported an extra distance, that is, longer than the expected predetermined distance. At the same time, the transportation roller rotates an amount corresponding to the above extra transported distance.
Thus, when the back end of the print sheet slips out from between the transportation roller 36 and the pinch roller 37 , the pinch roller 37 moves to the position at which it abuts against the outer peripheral surface of the transportation roller to have its position stabilized. Frictional resistance that may occur between the pinch roller 37 and the print sheet and the transportation roller 36 may vary slightly due to an environment or the like. Such a variation in frictional force may cause the transportation roller to be stopped while the roller is unstable. In this case, during a printing operation, the movement of the carriage or the like may cause the transportation roller to rotate to a stabilized position to transfer the print sheet. That is, the image, which should be printed along the main scanning direction, may be printed obliquely in a direction crossing the main scanning direction, thus degrading image quality.
Further, to deal with the above error in transportation, it is contemplated that for example, a brake may be provided to stop rotation of the transportation roller to restrain the print sheet P from being transported an extra distance when the sheet slips out. However, in this case, load torque required to drive the transportation roller increases, so that disadvantageously, a higher-grade drive motor must be used, and transportation speed cannot be increased.
SUMMARY OF THE INVENTION
The present invention is provided to solve these problems, and it is an object thereof to provide a printing apparatus and method that can use a simple configuration to reduce the deviate of an image printed position caused by inappropriate transportation of a print sheet during a printing operation which transportation may occur when the back end of the sheet slips out from a transporting means.
Thus, the present invention has the following configuration:
A printing apparatus including transporting means for transporting a print medium relative to printing means for printing an image on a print sheet is characterized by further comprising vibrating means for vibrating the transporting means before the printing means start a printing operation.
Further, a printing method which includes transporting means for transporting a print medium relative to printing means for printing an image on a print sheet and which uses the transporting means to transport the print medium after the printing means has performed a printing operation is characterized by comprising the step of vibrating the transporting means before the printing means start the printing operation.
With the above configuration, before the printing means performs a printing operation on the print medium, the transporting means is vibrated. Thus, if the transportation roller is at a position where it sits unstably, image corrections can be executed after the roller is stopped at a position where it sits stably. This prevents disturbed image printing, that is, oblique printing caused by slight movement of the transportation roller during a printing operation, thereby obtaining a high-quality image.
Further, the present invention requires no brake mechanism that prevents inappropriate movement of the print medium, thereby precluding load torque required for the transporting means from increasing unnecessarily.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart showing a printing operation according to a first embodiment of the present invention;
FIG. 2 is a view useful in describing the printing operation according to the first embodiment of the present invention;
FIG. 3 is a plan view of a printing apparatus according to the first embodiment of the present invention;
FIG. 4 is a side view of the printing apparatus;
FIG. 5 is a transverse sectional view of the printing apparatus;
FIG. 6 is a view showing a mechanism that mainly detects the quantity of rotations of a transportation roller of the printing apparatus;
FIG. 7 is a view showing print control according to the first embodiment of the present invention on the basis of printed areas of a print sheet;
FIGS. 8A to 8 C are views useful in describing the print control for each printed area;
FIG. 9 is a side view useful in describing vibrating means according to a second embodiment of the present invention;
FIG. 10 is a side view useful in describing vibrating means according to a third embodiment of the present invention;
FIG. 11 is a transverse sectional view showing a printing apparatus according to a conventional example; and
FIGS. 12A and 12B are views showing the relationship between a transportation roller and a pinch roller in the conventional printing apparatus.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Embodiments of the present invention will be described below in detail with reference to the drawings.
<Embodiment 1>
A printing apparatus according to this embodiment has an automatic sheet feeding unit installed therein, and in this state, has mechanism sections including the sheet feeding unit, a sheet transporting section, a sheet discharging section, a carriage section, and a cleaning section. Further, in addition to these mechanism sections, the printing apparatus is equipped with a control section in the form of a substrate which control an operation of each mechanism section, described later, and which executes processing for printing data, transportation of a printing sheet or the like. The control section has a CPU, a ROM, a RAM and others as in a case with well-known printing apparatuses. Further, printing heads used in this printing apparatus are based on an ink jet method. Specifically, the printing heads employ what is called the BJ method which uses thermal energy generated by an electric-thermal transforming element to generate a bubble in ink to allow the ink to be ejected using pressure of the bubble.
The mechanism sections are shown in FIGS. 3 to 5 . FIG. 3 is a front view of this printing apparatus, FIG. 4 is a side view thereof, and FIG. 5 is a traverse sectional view thereof. The above mentioned mechanism sections will be described below mainly with reference to the transverse sectional view of this printing apparatus shown in FIG. 5 .
(A) Sheet Feeding Section (Sheet Feeding Unit)
In FIG. 5 , the sheet feeding section 2 is constructed by installing the automatic sheet feeding unit in the printing apparatus main body. The automatic sheet feeding unit has a base 20 , which is provided with a pressure plate 21 on which printing sheets P are loaded and a sheet feeding roller 28 that feeds the printing sheet P. The sheet feeding roller 28 has a D-shaped cross section formed by partially cutting a circle. The pressure plate 21 is equipped with a movable side guide 23 that can restrict the loaded position of the printing sheets P. The pressure plate 21 is rotatable around a rotating shaft formed on the base 20 so that the urging force of a pressure plate spring 212 can urge the printing sheets P loaded thereon toward the sheet feeding roller 28 . Further, the pressure plate 21 and the movable side guide 23 have separating pads 213 (see FIG. 4 ) and 234 installed in sites thereof opposite to the sheet feeding roller 28 to prevent a plurality of printing sheets P from being fed with overlapping each other, the separating pads being each composed of a material such as artificial leather which has a large friction coefficient.
Further, the base 20 is equipped with a separating pad holder 24 which is rotatable around the rotating shaft installed on the base 20 and which is equipped with a separating pad 241 to separate the printing sheets P from one another. The printing sheets P are urged toward the sheet feeding roller 28 by a separating pad spring 242 . Further, against the separating pad holder 24 , a rotating roller holder 25 , which has a rotating roller 251 mounted thereon, is urged in the direction opposite to the above urging direction by a rotating roller spring 252 .
The automatic sheet feeding unit is equipped with a release cam gear 299 (see FIG. 4 ) to release the contact of the pressure plate 21 (or the printing sheets P loaded thereon) with the sheet feeding roller 28 . Rotation of the gear is set so that when the pressure plate 21 lowers to a predetermined position, a cut portion 285 of the sheet feeding roller 28 is located opposite the separating pad 241 . Thus, a predetermined space can be formed between the separating pad 241 and the sheet feeding roller 28 . At the same time, the rotating roller 251 contacts with the separating pad 241 to prevent a plurality of printing sheets from being fed with overlapping each other.
As described above, in a standby state, the release cam gear 299 pushes the pressure plate 21 down to a predetermined position to clear the contact between the pressure plate 21 and the sheet feeding roller 28 and between the separating pad 241 and the sheet feeding roller 28 . Then, in this state, when driving force applied to drive a transportation roller 36 of the sheet transporting section 3 , described later, is transmitted to the sheet feeding roller 28 and the release cam 299 via a gear or the like, the release cam 299 leaves the pressure plate 21 , which is thus elevated to cause the sheet feeding roller 28 to contact with the printing sheet P. As the sheet feeding roller 28 rotates, the printing sheet P are picked up and are then separated from one another by the separating pad 241 and fed to the sheet transporting section 3 . Then, once the printing sheets P has been fed into the sheet transporting section 3 , the contact of the sheet feeding roller 28 with both the pressure plate 21 and the separating pad 241 is cleared by the release cam gear 299 . Furthermore, once the fed printing sheet P has been completely printed and discharged, a return lever 26 acts on the printing sheets P placed on the separating pad 241 to allow the printing sheets P to be returned to their loaded position on the pressure plate 21 .
The return lever 26 and the sheet feeding roller 28 are driven by driving force for the transportation roller 36 transmitted via predetermined gears. The transmission of the driving force is switched by a solenoid 271 , solenoid spring 272 , solenoid pin 273 , and planetary gear arm 274 of a drive switching section 27 (see FIG. 2 ). More specifically, when the solenoid pin 273 acts on the planetary gear arm 274 to restrict its movement, the driving force for the transportation roller 36 is not transmitted. On the other hand, when the solenoid pin 273 is separated from the planetary gear arm 274 , the planetary gear arm 274 becomes free to transmit the driving force to the return lever 26 and the sheet feeding roller 28 as the transportation roller 36 rotates forward or backward.
(B) Sheet Transporting Section
A chassis 8 (see FIG. 4 ) formed by bending a sheet metal and constituting a structural member of the printing apparatus main body has elements mounted thereon, which constitutes the sheet transporting section 3 . More specifically, the sheet transporting section 3 is constructed by including a pair of the transportation roller 36 and a pinch roller 37 , provided at an upstream side of the printing area covered by the printing head, in the transporting direction, and a pair of a sheet discharging roller 41 and a spur 42 , provided at a downstream side of the printing area in the same direction. The transportation roller 36 is formed by coating the surface of a metal shaft with ceramic particles, and has shafts installed at the respective ends thereof and each supported by one of the two bearings 38 (One of them is shown in FIG. 3 . The other is not shown) installed at the respective ends of a chassis 8 .
A plurality of pinch rollers 37 , which follow each other, are provided so that they can contact with the transportation roller 36 . The pinch rollers 37 are held by a pinch roller holder 30 , and when the holder is urged by a pinch roller spring 31 , the pinch rollers 37 comes into pressure contact with the transportation roller 36 to generate force required to transport the printing sheet P. At this time, a rotating shaft of the pinch roller holder 30 is mounted on a bearing of an upper guide 33 installed on the chassis 8 , and the pinch roller holder 30 rotates around this shaft. The pinch roller holder 30 is integrally formed and has fixed or higher rigidity in a direction in which the printing sheets P are transported. By further setting relatively low rigidity in a direction perpendicular to the above transportation direction, the urging force of the pinch roller spring 31 appropriately acts on the pinch rollers 37 . Further, all the pinch rollers 37 are constructed substantially parallel with the rotating shaft of the transportation roller 36 (see FIG. 1 ) as described above. The pinch roller holder 30 and the upper guide 33 also act as a guide for the printing sheets P. Furthermore, an inlet of the sheet transporting section 3 , to which the printing sheet P is transported from the above described sheet feeding portion 2 , has a platen 34 disposed thereat to guide the printing sheet P. Further, the upper guide 33 is equipped with a PE sensor lever 35 that activates a PE sensor 32 for detecting front and back ends of the printing sheet P. Additionally, the platen 34 is mounted and positioned on the chassis 8 . The pinch rollers 37 according to this embodiment are formed of resin such as POM which allows an object to slide well thereon, and each have an outer diameter set between about φ3 and 7 mm.
Further, the platen 34 has a sheet presser (not shown) installed on a sheet reference side thereof and which covers the corresponding end of the printing sheet P. Thus, even if the end of the printing sheet P is deformed or curved, it is prevented from floating to interfere with a carriage 50 or printing heads 7 .
A carriage portion 5 , described later, is constructed above the sheet transporting section 3 . The carriage portion has the printing heads 7 mounted thereon and which perform a scanning operation to eject ink to the printing sheet P for printing, the printing sheet P being transported by the pair of the transportation roller 36 and the pinch roller 37 and the pair of the sheet discharging roller 41 and the spur 42 . In this printing operation, the printing sheet P that has been fed to the sheet transporting section 3 is guided to the pair of the transportation roller 36 and the pinch roller 37 by the platen 34 , the pinch roller holder 30 , and the upper guide 33 . At this time, the PE sensor lever is operated by the front end of the transported printing sheet P, to detect the front end of the printing sheet P. Then, based on the result of the detection, a printing position on the printing sheet P can be determined. Further, an LF motor 88 drives and rotates the pair of the rollers 36 and 37 to transport the printing sheet P on the platen 34 , and the transportation roller 36 has an encoder wheel 361 (see FIG. 3 ) mounted thereon to detect the rotary position thereof. The encoder wheel 361 is composed of a disk-shaped transparent sheet having radial markings formed thereon at predetermined pitches. The rotary position or quantity of rotation of the transportation roller 36 can be determined when an optical encoder sensor 362 (see FIG. 3 ) fixed to the chassis 8 detects these marks.
The carriage portion 5 , as described before, has the printing heads 7 and ink tanks from which black and color inks are supplied to the printing heads 7 , which are individually arranged for the respective ink colors and individually detachable from the carriage. Also as described above, the printing head 7 has a heater to heat the ink so that film boiling is caused in the ink to generate a bubble, and change in pressure caused by grow or contract of the bubble causes the ink to be ejected from the nozzles of the printing heads 7 . Thus, printing of an image on the printing sheet P can be performed. The printing heads 7 for the respective color inks have the nozzles, constituting printing elements, arranged parallel with the direction in which the printing sheet is transported. Thus, inoperative nozzles can be set and this setting can be used to execute corrections according to an error in transportation of the printing sheet, as described later with reference to FIGS. 8B and 8C .
(C) Carriage Portion
The carriage portion 5 has a carriage 50 , to which the printing heads 7 are mounted. The carriage 50 is supported by a guide shaft 81 (see FIG. 3 ) extending in the direction perpendicular to the direction in which the printing sheet P is transported and a similarly extending guide rail 82 (see FIG. 1 ) that holds a rear end of the carriage 50 to maintain a gap between the printing heads 7 and the printing sheet P.
Further, the carriage 50 is driven by a carriage motor 80 (see FIG. 3 ), which is mounted on the chassis 8 , via a timing belt 83 (see FIG. 3 ). The timing belt 83 is extended and supported by idle pulleys 84 (see FIG. 3 ). Furthermore, the carriage 50 is equipped with a flexible substrate 56 (see FIG. 3 ) to transmit printing signals or the like from an electric substrate 9 constituting the above described control section, to the printing heads 7 .
With the above configuration, for printing on the printing sheet P, the pair of the rollers 36 and 37 transports the printing sheet P to a row position to be printed (a position on the printing sheet P in the transportation direction), and the carriage motor 80 moves the carriage 50 to a column position to be printed (a position on the printing sheet P in the direction perpendicular to the transportation direction) to scan the printing heads 7 on the printing sheet. Then, during this scanning operation, on the basis of printing signals or the like from the control section, the printing heads 7 are driven to eject the ink to the printing sheet P, thereby printing the image or the like.
(D) Sheet Discharging Section
The pair of the sheet discharging roller and spur in the sheet transporting section constitute a sheet discharging section. More specifically, a spur base 341 (see FIG. 3 ) has the spurs 42 rotatably provided therein correspondingly to the sheet discharging rollers 41 and against which the spurs are contacted. The sheet discharging rollers 41 can be driven by that a transmission roller 40 transmits driving force for the transportation roller 36 to the sheet discharging roller.
The sheet discharging rollers 41 is formed as a plurality of roller portions each of which is made of a high-friction material such as rubber, and is disposed on a shaft consisting of metal or resin (see FIG. 3 ). Further, each of the spurs 42 has a thickness of about 0.1 mm, has protrusions formed on its outer circumference, and is composed of a metal plate such as SUS (stainless steel) and a resin portion consisting of POM and forming a rotating bearing.
The transmission roller 40 , which transmits driving force to the sheet discharging roller 41 , is disk shaped, is composed of POM or the like, and has a low-hardness and high-friction material such as styrene-based elastomer attached on the outer circumference thereof. The transmission roller 40 is contacted against both the transportation roller 36 and the sheet discharging roller 41 at a predetermined pressure, thereby transmitting driving force therebetween.
With the above configuration, the printing sheet P on which printing has been carried out through a scanning operation of the printing heads of the carriage portion 5 is transported with being held by nipping of the sheet discharging roller 41 and spur 42 , and is then discharged to a sheet discharging tray or the like. During this transportation, once the back end of the printing sheet P has slipped out from the transportation roller 36 and the pinch roller 37 , the printing sheet P is transported or discharged with being held only by the sheet discharging roller 41 and spur 42 of the sheet discharging section. Then, a printing operation is performed or the printing sheet is discharged. Further, a spur cleaner contacts with each of the spurs 42 to enable ink and the like deposited on the spur 42 to be removed.
(E) Cleaning Section
A cleaning section 6 (see FIGS. 3 and 4 ) has a pump (not shown) used for ejection recovery operation for the printing heads 7 and a cap (not shown) that restrains the ink in each nozzle of the printing head from drying.
FIG. 6 is a view useful in describing a detection mechanism that detects a rotary position or quantity of rotation of the transportation roller 36 .
As described above, the transportation roller 36 has an encoder wheel 361 mounted thereon. Specifically, the encoder wheel 361 can be centered by press fitting it to the rotating shaft of the transportation roller 36 , and is bonded to an LF pulley 364 to increase its strength. The encoder wheel 361 is, as shown in FIG. 4 , a disk-shaped, and transparent sheet, and has radial markings formed thereon at predetermined pitches. With respect to the encoder wheel, an optical encoder sensor 362 is provided in a fixed state for detecting the markings on the encoder wheel 361 to determine the rotary position or quantity of rotation of the transportation roller 36 . That is, each time any of the marks on the encoder wheel 361 reaches the position of the encoder sensor 362 as the transportation roller 36 rotates, a corresponding detection signal is generated and transmitted to the control section. The control section counts the number of detection signals starting with a predetermined reference rotary position to determine the rotary position or quantity of rotation of the transportation roller 36 . The detected quantity of rotation can be used for an image position correcting process, described later in FIGS. 8A to 8 C.
The transportation roller 36 is driven by transmitting the driving force of the LF motor 88 via an LF belt 363 , as shown in FIG. 6 . More specifically, the above transmission can be carried out by installing an LF belt 363 , at a predetermined pressure, on an LF motor pulley 881 attached to the LF motor 88 and on an LF pulley 364 attached to the transportation roller 36 . Further, FIG. 6 shows configuration that transmits the driving force for the transportation roller 36 to the sheet discharging roller via the transmission roller 40 , described previously.
Next, a printing operation performed by the above configuration will be described with reference to FIGS. 1 , 2 , 7 , and 8 . Before a rear end of the print sheet P reaches to a printing area by a transportation roller (step 900 ), a printing is performed by step 907 .
As shown in FIGS. 1 and 2 , the print sheet P is transported (step 900 ), and if its back end reaches a back end printed area (K), that is, a predetermined range close to the nips of the transportation roller 36 and the pinch roller 37 (step 901 ), then the carriage is reciprocated (step 902 ) to vibrate the transportation roller 36 . As a result, the encoder wheel 361 and the encoder sensor 362 determine whether or not the pinch roller 37 is deviate from its appropriate position relative to the transportation roller 36 (step 903 ). Since the carriage is moved to vibrate the transportation roller 36 , no image is formed or no ink is ejected from the print heads. In this case, if the transportation roller is not deviate from its appropriate position, a carriage scanning operation is performed to eject ink from the print heads to form an image (step 905 ), the print sheet P is transported again (step S 906 ), and the process returns to step 901 .
Further, when the print sheet P slips out from the downstream nip portions of the transportation roller 36 and pinch roller 37 , the transportation roller may be rotated due to the pressing force of the pinch roller 37 and thus deviate from its appropriate rotating position, as described previously. In this case, image corrections are executed (step 904 ) as described later. If the transportation roller 36 is rotated in this manner, it becomes stable.
The transportation roller 36 may rest at any appropriate rotary position where the pressing force of the pinch roller 37 and rotational sliding resistance from the transportation roller 36 are balanced. In this case, if in this balanced state, a printing operation is performed by moving the carriage as in the prior art (S 907 ), then vibration associated with this operation may clear the well-balanced stopped state of the transporting roller 36 to rotate the roller 36 during the printing operation. If the transportation roller is rotated during the printing operation, the image to be formed along the main scanning direction (carriage moving direction) may be obliquely printed to degrade image quality.
Then, in this embodiment, after the print sheet has been transported (step 900 ), the carriage 5 is reciprocated to vibrate the transportation roller 36 . Thus, if the transportation roller is in an unbalanced state, it is rotated to a stabilized position where it is no longer rotated. This rotation of the transportation roller 36 may deviate the printed position. Thus, to prevent the image from being degraded due to this deviate, the image corrections described later are executed before the image is formed. This enables an undisturbed high-quality image to be formed. Vibration caused by the carriage 5 is transmitted from the guide shaft 81 to the transportation roller 36 via the chassis 8 .
The printing operation performed by the printing apparatus of the embodiment described above, notably the image position correction, will be described with reference to FIGS. 7 and 8 .
FIG. 7 is a view for explaining a process of controlling the printing operation differently for each area of the printing sheet and the like. FIGS. 8A to 8 C show an operative range of the nozzles of the printing heads for each of the different printing control processes.
In this embodiment, a multipass printing process is executed in which a printing area printed through a scanning operation performed by the printing heads is printed through a plurality times of scanning operation and different nozzles are used for the respective scanning operations. In this embodiment, the multipass printing process is controlled differently between an area completely printed through four scanning operations (4-passes area) and an area completely printed through six scanning operations (6-passes area), as shown in FIG. 5 . More specifically, in the 4-passes area, four nozzle blocks obtained by dividing all the nozzles of the printing heads into four are used, and the normal printing operation shown in FIG. 8A is performed in the corresponding areas. In the 6-passes area, six nozzle blocks obtained by dividing six-eighths of all the nozzles into six are used, and basically the after-pass-switch printing operation shown in FIG. 8B is performed.
In the transportation for printing on a back end portion of the printing sheet P, the back end of the printing sheet slips out from the pair of the transportation roller and pinch roller, located upstream, and is transported only by the pair of the sheet discharging roller and the spur, located downstream. In this case, since transportation accuracy may decrease, an amount of printing sheet transported during a single transporting operation is reduced to lessen possible transportation errors. At the same time, the number of times of scanning operation for the same printing area in the multi-pass printing process is increased to make unevenness of print density, which may be caused by the above transportation errors, unnoticeable. Because of this, in this embodiment, the 6-passes area is provided correspondingly to the back end portion of the printing sheet transported, so that the amount of printing sheet transported during a single transporting operation is smaller than in the 4-pass area and six passes (six times of scanning operation) are executed.
The number of passes is controlled to be switched when the “pass switching position” of the printing sheet P, shown in FIG. 7 , reaches the position at the pair of the transportation roller 36 and the pinch roller 37 in the transportation of the printing sheet. This position can be detected by, for example, detecting the front end of the printing sheet and then detecting that a predetermined number of transporting operations (or a predetermined amount of rotation of the transportation roller) corresponding to this position have been performed from detecting of the front end.
In the transportation of the printing sheet, when the printing sheet passes the above pass switching position and then reaches the position at which the printing sheet slips out from the transportation roller and the pinch roller (the back end of the printing sheet leaves the pair of the rollers 36 and 37 ), basically the after-pass-switch printing operation is performed shown in FIG. 8 B. However, as described below, when it has been detected that the printing sheet has been transported a distance longer than a predetermined one, then immediately after the detection, the after-nozzle-shift printing operation shown in FIG. 8C is performed.
During the normal printing operation shown in FIG. 8A , each of the printing heads 7 for black (Bk), cyan (C), magenta (M), and yellow (Y) uses all the nozzles to perform the 4-passes printing operation. Accordingly, the amount of printing sheet P transported during a single transporting operation is one-fourth of the entire nozzle arranged length, so that a printing area corresponding to the above one-fourth distance is completely printed through four times of scanning operation performed by the printing heads. As the printing sheet P is transported, the 4-passes printing operation is continuously performed until the above described “pass switching position” of the printing sheet P is reached, thereby completing printing this 4-pass area. In the final stage in which the 4-passes area is completely printed, some of the nozzles of each printing head are opposite to the 6-passes area. Thus, to avoid using these nozzles, the operative portion of the nozzles are shifted correspondingly to the amount of printing sheet transported during a single transporting operation, thus first completing printing only the 4-pass area. The switching between the numbers of passes is controlled in this manner in order to simplify software used, and of course the switching process is not limited to the above example.
Once the 4-passes area has been completely printed, the after-pass-switch printing operation shown in FIG. 8B is performed, that is, the operation is switched to the 6-pass printing. During this printing operation, the operative portion of the nozzles is limited by setting some of the operative nozzles of each printing head 7 as an inoperative portion. In this embodiment, two-eighths of the nozzles are set as an inoperative portion, with the remaining six-eighths of the nozzles used for printing. Since this operative range is used to perform the 6-pass printing operation, the amount of printing sheet P transported during a single transporting operation corresponds to one-eighth of the entire nozzle range length.
In the 6-pass printing operation, when the back end of the printing sheet P slips out from the transportation roller 36 and the pinch roller 37 , the transportation roller 36 may be rotated more than a predetermined distance due to the pressure exerted by the pinch roller 37 , as described before. This extra rotation is detected by the encoder wheel 361 and the encoder sensor 362 , the extra amount of rotation of the transportation roller 36 is detected. Then, a correction amount is determined based on the detected extra amount, as shown in FIG. 8C , to shift the operative portion of the nozzles of each printing head 7 at a distance corresponding to the extra amount of rotation using the inoperative portion of the nozzles.
More specifically, the control section, which executes data processing and control of operations in the printing apparatus, for example refers to a table by the detected extra amount, obtains a number of nozzles corresponding to the extra rotation amount, and supplies printing data to a head driver so as to shift the operative nozzles as a whole correspondingly to the obtained the number of nozzles. Strictly, though the detected extra amount does not always coincide with a sift amount, the above table is configured so that the most approximate shift amount is set to the detected extra amount. With the above processing, the operative portion of the nozzles of each printing head is shifted relative to the printing sheet P, which has been transported the extra distance, thereby preventing the position of the image printed on the printing sheet from deviating from parts of the image printed during previous scanning operations. Thus, according to this embodiment, even with the relative positional deviation of the printing head position from the printing sheet position, which may occur because the printing sheet is transported the extra distance when it slips out from the upstream roller pair, an appropriate printing operation can be performed without any printing degradation such as the positional deviation of the printed image.
Further, if the positional deviate of the transportation roller 36 is detected in step 903 in FIG. 1 , then it may be corrected by rotationally driving the transportation roller to the appropriate position again in addition to carrying out the above described nozzle shift.
Thus, a good image can be formed with few printing errors.
<Second Embodiment>
Now, a second embodiment of the present invention will be described.
In the first embodiment, the carriage 50 is reciprocated to vibrate the transporting means, but in the second embodiment, the transporting means is vibrated by moving the pressure plate 21 of the sheet feeding section in the vertical direction.
That is, in the first embodiment, the release cam gear 299 and the sheet feeding roller 28 operate in an interlocking manner, so that when the pressure plate 21 operates, the sheet feeding roller 28 rotates to feed a sheet. In contrast, in the second embodiment of the present invention, the linkage between the pressure plate 21 and the sheet feeding roller 28 is interrupted, so that the pressure plate 21 is moved forward and backward relative to the sheet feeding roller 28 independently of driving of the sheet feeding roller 28 , using a solenoid 920 or the like, as shown in FIG. 9 .
In this case, the solenoid 920 is held by the main body portion of an automatic sheet feeding device. Further, driving means (not shown) drives and stops a plunger 920 a so as to move it forward and backward relative to the pressure plate 21 , thereby pressing and releasing, that is, vibrating the pressure plate 21 .
With the above configuration, as shown in FIG. 2 , if the back end of the print sheet P lies in the back end printed area (K), the sheet is transported (step 906 ), and the plunger 902 a is then moved away from the pressure plate 21 . Thus, the pressure plate 21 abuts against the sheet feeding roller 28 due to the pressing force of a pressure plate spring 212 , and an impact occurring upon the abutment causes vibration. In this case, the sheet feeding roller 28 is not rotated, so that the sheet feeding operation is not performed even if any print sheets P remain on the pressure plate 21 .
If this vibration may shift the transportation roller 36 to its stabilized position, image corrections or the like are executed.
The other parts of the configuration and operation of this embodiment are similar to those of the first embodiment.
<Third Embodiment>
Now, a third embodiment of the present invention will be described. In the above embodiments, the transporting means is vibrated by reciprocating the carriage 50 or moving the pressure plate 21 in the vertical direction, but in the third embodiment of the present invention, the pinch roller holder 30 is vibrated as shown in FIG. 10 .
That is, FIG. 10 shows the third embodiment, wherein the pinch roller holder 30 , having the pinch roller 37 rotatably supported at one end thereof, has its central portion rotatably supported on the chassis 8 . Further, the chassis 8 also holds a solenoid 921 having a plunger 921 a located opposite the other end of the pinch roller holder 30 . The pinch roller holder 30 is urged by the spring 31 so that the other end thereof abuts against the plunger 921 a. The solenoid 921 is held by the chassis 8 so that the plunger 921 a is located opposite the other end of the pinch roller holder 30 .
With the above configuration, if the back end of the print sheet P lies in the back end printed area (K), the pinch roller holder 30 is vibrated by moving the plunger 921 a forward and backward after the print sheet has been transported. Then, vibration is transmitted from the pinch roller holder 30 to the pinch roller 37 and the transportation roller 36 , which thus rotates to its stabilized position if it has been in an unstable state. Thus, image corrections can be executed if the position of the transportation roller 36 is deviate.
The other parts of the configuration and operation of this embodiment are similar to those in the first embodiment.
In the above embodiments, the members and driving sources already installed in the printing apparatus are utilized to constitute all or part of the vibrating means, thereby simplifying the configuration and reducing costs.
However, the present invention is not limited to the above embodiments, but a self-vibrating device that is perfectly independent of the printing apparatus may be additionally provided without using any of the existing members of the printing apparatus.
Further, in the above embodiments, the transporting means for transporting a print medium has been illustrated as the transportation roller and pinch roller which transport the print medium by sandwiching it therebetween. The present invention is not limited to the transporting means that transports the print medium by sandwiching it therebetween, but is effectively applicable to other transporting means having other configurations. For example, the present invention is applicable to, for example, a printing apparatus in which continuous paper having punches formed at the opposite ends thereof is transported by a sprocket (movable member) that engages with the punches.
The above embodiments have been described in conjunction with the print heads based on the ink jet method, notably what is called the BJ method, but the present invention is applicable without depending on these printing methods for the print heads, as is apparent from the description of the embodiments. As a printing method for the print heads, for example, a piezo method may be used instead of the BJ method. Alternatively, print heads may be used which are based on a thermal transfer method or the like instead of the ink jet method and which thus have print elements arranged therein.
As described above, according to the present invention, the transporting means is vibrated before the printing means performs a printing operation on a print medium. Thus, if the transporting member of the transporting means is in an unstable state, image correcting and printing operations can be performed after the transporting means has been moved to its stabilized position. This configuration also prevents the disturbance of the image, that is, oblique printing caused by inappropriate transportation of the print sheet during a printing operation.
Further, the present invention requires no brake or the like, which increases load torque required for the transporting means, thereby eliminating the need to use a higher-grade driving source and allowing the apparatus to be inexpensively constructed.
The present invention has been described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and it is the intention, therefore, in the appended claims to cover all such changes and modifications as fall within the true spirit of the invention. | It is an object of the present invention to use a simple configuration to reduce the deviate of an image printed position caused by the behavior of a print sheet when the back end of the sheet slips out from an upstream roller pair. Thus, the present invention provides a printing apparatus including transporting section for transporting a print medium relative to printing heads for printing an image on a print sheet, the apparatus comprising vibrating section for vibrating the transporting section. This vibrating section vibrates the transporting section before the printing heads start a printing operation. Thus, even if the transporting section is stopped at an unstable position when a transporting operation is stopped, the applied vibration brings the transporting section into a stable state sufficiently before a printing operation is started. | 1 |
TECHNICAL FIELD
[0001] This patent application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/136,902 that was filed on Mar. 23, 2015, for an invention titled CLASSROOM RETROFIT BARRIER.
TECHNICAL FIELD
[0002] The present invention relates generally to ballistic barriers. More specifically, the present invention relates to a system and method for retrofitting an entryway to a classroom or the like.
BACKGROUND
[0003] In today's society there has arisen a need to provide protection for students against active shooters (gunmen) attacking defenseless victims on school campuses. There are many approaches being considered for such protection including but not limited to; more campus police, arming teachers, ballistic backpacks, etc.
[0004] One approach is disclosed in U.S. Pat. No. 9,145,729 entitled Classroom Ballistic Barriers, issued Sep. 29, 2015 to DAW Technologies, LLC, where the barrier system comprised a ballistic panel nested slidably in upper and lower channels to slide across a doorway and lock into position. The sliding ballistic panel operates independent of the classroom door and manually must be slid across the doorway opening. Similarly, in U.S. Pat. No. 9,234,724, also entitled Classroom Ballistic Barriers and issued Jan. 12, 2016 to DAW Technologies, LLC, a barrier system comprised of one or more ballistic panels slide across door or window openings to provide ballistic shielding against attacks through such openings. Again, the sliding ballistic panels operate independent of the classroom door or window and manually must be slid across the opening. Such systems and other efforts to shield students from active shooters have their drawbacks. Many such systems are made of expensive materials and can be time-consuming and expensive to install. Also, they may compromise the ability to make an emergency exit from the classroom.
[0005] What is needed is a ballistic shielding solution that is effective, requires minimal effort to deploy, and is cost-effective for schools or office buildings to purchase and install. The embodiments of the present disclosure may cost-effectively turn almost any classroom into a “safe room”. Creating “safe rooms” on campuses drastically reduces or eliminates the “opportunity” and permits trained professionals adequate time to respond to the threat. The retrofit barrier of the present disclosure has a non-alarming appearance to students; it is simple to operate; it is be bullet resistant; and it prevents breaching for some predetermined length of time, thus allowing time for local police/SWAT to respond.
SUMMARY OF THE INVENTION
[0006] The classroom ballistic barriers of the present disclosure provide barrier-of-entry shielding that may be retrofit to the existing classroom door by the school's own maintenance staff and will not inhibit emergency exits through the door. The system and method of the present disclosure combines a minimally-thick ballistic skin with a solid-core wood as is typically used as a classroom door to create a shield equivalent to a N.I.J. Level IIIA ballistic panel. Hence, it is possible to retrofit a relatively thin ballistic skin onto an existing door to provide protection against multiple 0.44 magnum and 9 mm handgun blasts, as well as multiple 12-gauge shot gun blasts. The ballistic skin comprises ballistic fiberglass reinforced plastic (FRP) material. N.I.J. Level IIIA protection must stop five rounds from a 0.44 magnum or five rounds from a 9 mm handgun within a 12″×12″ square shot 16 feet 4 inches away, with no penetrations. Normally, to achieve N.I.J. Level IIIA protection with this type of material, it would require a minimum of a ½″ thickness. Because this material weighs approximately 6 pounds per square foot, providing that thickness would add too much weight to the door, would make it difficult for a single maintenance person to install, and would add unnecessary cost. However, by applying the ballistic skin of a ¼″ thickness to an existing door, the weight of the ballistic shielding is cut in half making it capable of installation by a single maintenance person, and the cost of the shielding is significantly reduced. Moreover, by using lightweight (thinner) ballistic material, the added weight will not fatigue the existing door, nor will the shielding protection provided be exorbitantly expensive for schools.
[0007] In an exemplary embodiment, mechanical fasteners are used to ensure that the door will perform consistently against ballistic threats versus adhesive or double-sided adhesive tape. The adhesives suitable for securing the ballistic skin to a typical classroom door can vary greatly depending upon the substrate or substrate preparation. Hence, to use adhesives to secure the ballistic skin to the door can add unnecessary complexity to a retrofit installation. By using mechanical fasteners, a residing maintenance worker for each school and/or office building is likely skilled sufficiently to install the ballistic skin to the door. Furthermore because it is imperative that the ballistic performance not be compromised because of inattention to detail, retrofit installations using mechanical fasteners is preferred. In short, the mechanical fasteners make for a fool-proof installation.
[0008] The ballistic skin is custom fit to each door with an array of holes predrilled into the skin enabling the installer to use the skin as a drill template during installation. The array of holes are spaced from the outer boundary edges of the ballistic skin and the number and position of the holes assure that the ballistic performance is not compromised and the ballistic skin remains secured to the door during a gunfire attack. To permit the existing door to properly close without the need for any modification of door or jambs, the ballistic skin is held spaced from the edges of the door so that the edges of the ballistic skin abuts the periphery of the jamb. Top and bottom ballistic skin clamps are provided to ensure a tight connection between the door and the ballistic skin without the need of any adhesives. Ballistic fiberglass reinforced plastic (FRP) is difficult to bond to since it has a relatively “greasy” surface, so using mechanical fasteners and the top and bottom skin clamps solve any bonding issues. The mechanical fasteners are tamper resistant through-bolts that are secured from classroom, non-threat side of the door. In some embodiments, the use of sex-bolts ensures that the fastener cannot be compromised from the hall, threat side of the door.
[0009] It should be understood, however, that the systems and methods of the present disclosure may also be used in new construction and in total door replacement situations. In these types of installations, it may be preferable to use an adhesive attachment of the ballistic skin to the door. Those skilled in the art will understand what types of adhesives would be suitable. Also, in the instance of total door replacement, the residing maintenance worker is likely capable of installing the replacement door, and in new construction, a qualified construction worker will handle the construction and hanging of the ballistic door.
[0010] If the door has a window, the window is replaced with a ballistic glazing and frame so that the ballistic panel overlaps at the joint between the door and the ballistic glazing. The ballistic glazing is fixed in place by the ballistic frame, comprising both an interior frame portion and an exterior frame portion, to ensure that the ballistic protection extends over the entire door area.
[0011] To shield the latch area of the door, a latch guard (hallway, threat side) and a latch support (classroom, non-threat side) are incorporated to protect the door against forced entry. With minimal alteration, the ballistic skin, a modified latch guard, and modified latch support may be fit onto a door that has panic hardware or fit panic hardware onto a door that has been retrofit with this ballistic skin. Those skilled in the art, armed with this disclosure would be able to make the minimal alterations to accommodate panic hardware.
[0012] The classroom ballistic barrier can be a sliding panel or hinged panel depending upon the configuration of the door opening or window opening to be blocked. The barrier must not inhibit, impede, or change the egress through the door. It must be simple to operate, it must be bullet resistant, and lastly it must be impenetrable for some predetermined length of time.
[0013] Because the barrier is located inside the door opening (for someone looking down a long hallway) it will not be immediately obvious which rooms are the “safe rooms.”
[0014] The ballistic barrier of the present disclosure is always in position whenever the door is closed and locked (in a normal locking fashion). The ballistic barrier in no way inhibits, impedes, or changes the safe egress through the door.
[0015] To accommodate various types of classroom or office building doors, the ballistic skins can be made to suit each type of these typical doors. Also, the classroom/office side of the ballistic skin may be made in various finishes to blend into the surroundings. In some embodiments, the ballistic skin may be covered with cork or a white board material. Hence, the classroom barrier can be disguised as a simple bulletin board for everyday use so as not to unduly alarm young students or inform would be assailants of its existence.
[0016] It has been considered that many different materials could be utilized in place of the ballistic fiberglass depending upon the likely threat, the desired complexity of the install, and response time of local law enforcement. Such materials are known to those of skill in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The manner in which the above-recited and other features and advantages of the disclosed exemplary embodiments are obtained will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only exemplary embodiments and are, therefore, not to be considered limiting of the scope of this disclosure, the exemplary embodiments of this disclosure will be described with additional specificity and detail through use of the accompanying drawings in which:
[0018] FIG. 1 is an elevation view from inside a room showing an exemplary ballistic barrier panel as applied to the inside of a classroom door.
[0019] FIG. 2 is an elevation view of the opposite side of the classroom door depicted in FIG. 1 showing the side outside of the classroom as in a hallway or the like.
[0020] FIG. 3 is a side elevation view of the classroom door depicted in FIG. 1 showing the door latch and protections at the door latch.
[0021] FIG. 4 is an elevation view of the classroom door depicted in FIG. 1 showing various section view references.
[0022] FIG. 5 is a perspective view of a portion of a door showing the outside door knob and latch guard used to inhibit tampering and/or opening the door when locked.
[0023] FIG. 6 is a perspective view of a portion of a door showing the inside door knob and latch support used to shield the door knob ballistically and to inhibit tampering and/or opening the door when locked.
[0024] FIG. 7 is horizontal section view of the classroom door of FIG. 4 viewed along line D-D above the door knob.
[0025] FIG. 8 is a horizontal section view of the classroom door of FIG. 4 viewed along line A-A showing the section of the interface of the door to an inset ballistic window.
[0026] FIG. 9 is a vertical section view of the classroom door of FIG. 4 viewed along line B-B showing the top ballistic skin clamp securing the ballistic skin.
[0027] FIG. 10 is a vertical section view of the classroom door of FIG. 4 viewed along line C-C showing the bottom ballistic skin clamp securing the ballistic skin.
[0028] FIG. 11 is a perspective view of an open doorway showing another exemplary embodiment of a shielded classroom door with panic hardware.
[0029] FIG. 12 is a perspective view of an open doorway showing yet another exemplary embodiment of a shielded classroom door with alternative panic hardware.
[0000]
REFERENCE NUMBERS
ballistic door 10
existing door 11
door latch 12
threat side 13
door knob 14
non-threat side 15
inset window 16
ballistic assembly 17
ballistic skin 18
top ballistic skin clamp 20
bottom ballistic skin clamp 22
ballistic glazing or window 24
ballistic frame 26
interior frame portion 28
exterior frame portion 30
mechanical fasteners 32
peripheral edges 34
outer boundary edges 36
joint 38
latch guard 40
latch support 42
panic hardware 44
array of holes 46
plurality of holes 48
through-holes 50
set of holes 51
window void 52
aligning holes 54
latch void 56
DETAILED DESCRIPTION
[0030] Exemplary embodiments of the present disclosure will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. It will be readily understood that the components of the exemplary embodiments of the present disclosure, as generally described and illustrated in the Figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of exemplary embodiments of the apparatus, system, and methods of the present disclosure, as represented in FIGS. 1 through 12 , is not intended to limit the scope of the invention, as claimed, but is merely representative of exemplary embodiments.
[0031] The phrases “connected to,” “coupled to” and “in communication with” refer to any form of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, fluid, and thermal interaction. Two components may be coupled to each other even though they are not in direct contact with each other. The term “abutting” refers to items that are in direct physical contact with each other, although the items may not necessarily be attached together.
[0032] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
[0033] The classroom ballistic barriers of the present disclosure are ingress barriers comprising at least one ballistic panel specifically designed to block entry through a locked classroom door or any other door where warding off an armed assailant is desirable.
[0034] Turning to FIGS. 1-4 , elevation views of an exemplary ballistic shield for a classroom door or any other door where such shielding would be desired are shown. FIG. 1 shows a ballistic door, generally designated 10 , as viewed from inside a room. The ballistic door 10 comprises and existing door 11 having a door latch 12 with a door knob 14 and an inset window 16 . The existing door 11 also having a threat side 13 and a non-threat side 15 . The exemplary embodiment of the ballistic door 10 also has a ballistic assembly 17 that may comprise a ballistic skin 18 , a top ballistic skin clamp 20 , a bottom ballistic skin clamp 22 , a ballistic window 24 , and a ballistic frame 26 , comprising both an interior frame portion 28 and an exterior frame portion 30 (not shown in FIG. 1 , see FIG. 2 ) that are secured to the existing door 11 . The ballistic skin 18 , the top ballistic skin clamp 20 and the bottom ballistic skin clamp are secured to the non-threat side 15 of the existing door 11 , while in cases where the existing door 11 has an inset window 16 , the ballistic frame 26 captures the ballistic window 24 (replacing the existing window) from both the threat side 13 and the non-threat side 15 .
[0035] As depicted in the Figures, the classroom ballistic barriers of the present disclosure provide barrier-of-entry shielding that may be retrofit to the existing classroom door 11 by the school's own maintenance staff and will not inhibit emergency exits through the door 11 . The system and method of the present disclosure combines a minimally-thick ballistic skin 18 with a solid-core wood as is typically used as a classroom door 11 to create a shield equivalent to a N.I.J. Level IIIA ballistic panel. Hence, it is possible to retrofit a relatively thin ballistic skin 18 onto an existing door 11 to provide protection against multiple 0.44 magnum and 9 mm handgun blasts, as well as multiple 12-gauge shot gun blasts. The ballistic skin 18 may comprise ballistic fiberglass reinforced plastic (FRP) material. For N.I.J. Level IIIA protection, the door 11 and ballistic skin 18 combination, constituting the ballistic door 10 , must stop five rounds from a 0.44 magnum or five rounds from a 9 mm handgun within a 12″×12″ square shot 16 feet 4 inches away, with no penetrations. Normally, to achieve N.I.J. Level IIIA protection with this type of material, it would require a minimum of a ½″ thickness of FRP. Because FRP material weighs approximately 6 pounds per square foot, providing that thickness would add too much weight to the door 11 , would make it difficult for a single maintenance person to install, and would add unnecessary cost. However, by applying the ballistic skin 18 of a ¼″ thickness to an existing door 11 , the weight of the ballistic shielding is cut in half making it capable of installation by a single maintenance person, and the cost of the shielding is significantly reduced. Moreover, by using lightweight (thinner) ballistic material, the added weight will not fatigue the existing door 10 , nor will the shielding protection provided be exorbitantly expensive for schools, offices, or the like. The use of lightweight (thinner) ballistic material, while not surrendering ballistic integrity for the door, is possible by always placing the ballistic material on the non-threat side of the door. This enables the solid core wood door to assist with and perform some of the work if stopping bullets.
[0036] In the exemplary embodiment shown in FIGS. 1-4 , mechanical fasteners 32 are used to ensure that the ballistic door 10 will perform consistently against ballistic threats versus adhesive or double-sided adhesive tape. The adhesives suitable to secure the ballistic skin 18 to a typical classroom door 11 can vary greatly depending upon the substrate or substrate preparation. Hence, to use adhesives to secure the ballistic skin 18 to the existing door 11 can add unnecessary complexity to a retrofit installation. By using mechanical fasteners 32 , a residing maintenance worker for each school and/or office building is likely skilled sufficiently to install the ballistic skin 18 to the existing door 11 . Furthermore, because it is imperative that the ballistic performance not be compromised because of inattention to detail, retrofit installations using mechanical fasteners 32 is preferred. In short, the mechanical fasteners 32 make for a nearly fool-proof installation.
[0037] The ballistic skin 18 is custom fit to each door 11 with an array of holes predrilled into the ballistic skin 18 enabling the installer to use the ballistic skin 18 as a drill template during installation. The array of holes are spaced from the outer boundary edges of the ballistic skin and the number and position of the holes assure that the ballistic performance is not compromised and the ballistic skin remains secured to the door during a gunfire attack. To permit the existing door 11 to properly close without the need for any modification of the existing door 11 or jambs (not shown, but see FIGS. 11 and 12 for context), the ballistic skin 18 is held spaced from the peripheral edges 34 of the existing door 11 so that the outer boundary edges 36 of the ballistic skin 18 abuts the periphery of the jamb. Top and bottom ballistic skin clamps 20 , 22 are provided to ensure a tight connection between the existing door 11 and the ballistic skin 18 without the need of any adhesives. As best seen in FIGS. 1, 4, 9, 11, and 12 , the top ballistic skin clamp 20 is shown securing the ballistic skin 18 to the existing door 11 to preserve the peripheral spacing of the ballistic skin 18 from the peripheral edges 34 of the existing door 11 so that the outer boundary edges 36 of the ballistic skin 18 abuts the periphery of the jamb when the ballistic door 10 is closed. Similarly, as best seen in FIGS. 1, 4, and 10-12 , the bottom ballistic skin clamp 22 is shown securing the ballistic skin 18 to the existing door 11 to preserve the peripheral spacing of the ballistic skin 18 from the peripheral edges 34 of the existing door 11 so that the outer boundary edges 36 of the ballistic skin 18 abuts the periphery of the jamb when the ballistic door 10 is closed.
[0038] Ballistic fiberglass reinforced plastic (FRP) is difficult to bond to since it has a relatively “greasy” surface, so using mechanical fasteners 32 and the top and bottom skin clamps 20 , 22 solve any bonding issues. The mechanical fasteners 32 may be tamper resistant through-bolts that are secured from classroom non-threat side 15 of the existing door 11 . In some embodiments, the use of sex-bolts ensures that the mechanical fastener 32 cannot be compromised from the hall or threat side 13 of the existing door 11 .
[0039] It should be understood, however, that the systems and methods of the present disclosure may also be used in new construction and in total door replacement situations. In these types of installations, it may be preferable to use an adhesive attachment of the ballistic skin 18 to the existing door 11 . Those skilled in the art will understand what types of adhesives would be suitable. Also, in the instance of total door replacement, the residing maintenance worker is likely capable of installing the replacement door 10 , and in new construction, a qualified construction worker will handle the construction and hanging of the ballistic door 10 .
[0040] If the existing door 11 has an inset window 16 as shown in the exemplary embodiment of FIGS. 1-4 , the inset window 16 is replaced with a ballistic glazing or ballistic window 24 and a ballistic frame 26 so that the ballistic skin 18 overlaps at the joint 38 between the existing door 11 and the ballistic glazing or window 24 . See FIG. 8 . The ballistic window 24 is fixed in place by the ballistic frame 26 , comprising both an interior frame portion 28 and an exterior frame portion 30 , to ensure that the ballistic protection extends over the entire ballistic door 10 area. Like the ballistic skin 18 , the ballistic frame 26 may be assembled and secured using mechanical fasteners 32 , such as sex-bolts bolts to ensure that the mechanical fasteners 32 cannot be compromised from the hall side of the existing door 11 .
[0041] To shield the door latch 12 area of the existing door 11 , a latch guard 40 (hallway, threat side 13 ) and a latch support 42 (classroom, non-threat side 15 ) are incorporated to protect the ballistic door 10 against forced entry. An exemplary latch guard 40 is best shown in FIGS. 2 and 5-7 , and an exemplary latch support 42 is best shown in FIGS. 1 and 4-7 .
[0042] With minimal alteration, the ballistic skin 18 , a modified latch guard 40 , and modified latch support 42 may be fit onto an existing door 11 that has panic hardware 44 or panic hardware 44 may be fit onto an existing door 11 that has been retrofit with this ballistic skin 18 to transform the existing door 11 into an alternative exemplary embodiment of a ballistic door 10 with panic hardware 44 . Those skilled in the art, armed with this disclosure would be able to make the minimal alterations to accommodate panic hardware 44 . Two exemplary alternative embodiments of ballistic doors 10 with alternative panic hardware 44 are shown in FIGS. 11 and 12 .
[0043] An exemplary method for preparing the ballistic assembly 17 for retrofit installation on an existing door 11 to be hung within a door jamb (see e.g., FIGS. 11 and 12 ) may include selecting a ballistic skin 18 having a thickness less than one-half inch and outer boundary edges 36 , the thickness of the ballistic skin 18 being sufficient, when secured to the non-threat side 15 of the existing door 11 , to create a ballistic door 10 having at least a N.I.J. Level IIIA of protection against gunfire. The ballistic skin 18 has a size such that the ballistic skin 18 is capable of being secured to the non-threat side 15 of the existing door 11 such that the outer boundary edges 36 are spaced from the peripheral edges 34 of the existing door 11 (see FIGS. 1 and 4 ) and the outer boundary edges 36 abuts the periphery of the door jamb when the ballistic door 11 is closed.
[0044] Once positioned as described above, an installer (whether a school's own maintenance staff worker or a qualified construction worker) may drill through-holes 50 through the existing door 11 by using the array of holes 46 in the ballistic skin 18 spaced from the outer boundary edges 36 as a template. See FIGS. 1 and 4 . The array of holes 46 and corresponding through-holes 50 are positioned to assure that the ballistic skin 18 remains secured to the existing door 11 during a gunfire attack. For additional assurance that the ballistic skin 18 remains secured to the existing door 11 , a top ballistic skin clamp 20 and a bottom ballistic skin clamp 22 each having a length less than or equal to the horizontal (or width) dimension of the ballistic skin 18 may be selected and a plurality of holes 48 may be drilled through the top ballistic skin clamp 20 and the bottom ballistic skin clamp 22 to align with top and bottom portions of the array of holes 46 through the ballistic skin 18 along the top and bottom horizontal dimensions of the ballistic skin 18 , respectively, to align with the respective portions of the array of holes 46 .
[0045] In some exemplary embodiments, the existing door may have an inset window 16 . In such cases, an exemplary method for preparing the ballistic assembly 17 for retrofit installation on an existing door 11 may include cutting away a portion of the ballistic skin 18 that would align with the size and location of the inset window 16 to create a window void 52 . A ballistic frame 26 having an interior frame portion 28 and an exterior frame portion 30 may be selected or made to have a size and shape to encase the window void 52 in the ballistic skin 18 and the inset window 16 in the existing door 11 . See FIGS. 1, 2, 4, and 8 . A set of holes 51 may be drilled through the ballistic skin 18 spaced from and surrounding the window void 52 , and aligning holes 54 may be drilled in the internal frame portion 28 and corresponding external frame portion 30 to align with the set of holes 51 in the ballistic skin 18 that surround the window void 52 . A ballistic window 24 having a size and shape to replace the inset window 16 may be cut or selected such that it may be encased within the window void 52 in the ballistic skin 18 by the ballistic frame 26 .
[0046] Whether the existing door 11 has an inset window 16 or not, it will have some type of door latch 12 having door knobs 14 or panic hardware 14 , for example. See FIGS. 1, 2, 4-7, 11 , and 12 . Preparing a ballistic assembly 17 for retrofit installation on an existing door 11 with a door latch may require cutting away a portion of the ballistic skin 18 that would align with the size and location of the door latch 12 to create a latch void 56 , which may or may not include accommodating a dead bolt (not shown). A latch guard 40 may be secured to the threat side 13 of the existing door 11 to prevent jimmying the ballistic door 10 open manually or by gunfire. Also, a latch support 42 having a size greater than the latch void 56 may be secured to the non-threat side 15 of the existing door 11 to cover the latch void 56 in an overlapping fashion so that gunfire directly into the door latch 12 will not compromise the ballistic protection of the ballistic door 10 .
[0047] An exemplary method of retrofit installation of a ballistic assembly 17 to an existing door 11 includes positioning a ballistic skin 18 having outer boundary edges 36 against the non-threat side 15 of the existing door 11 . The ballistic skin may have a size such that the ballistic skin 18 is capable of being secured to the non-threat side 15 of the existing door 11 in a manner that the outer boundary edges 36 are spaced from the peripheral edges 34 of the existing door 11 , and the outer boundary edges 36 abuts the periphery of the door jamb (not shown, but see FIGS. 11 and 12 for examples of a door jamb) when the ballistic door 10 is closed. The ballistic skin 18 may have been prepped before installation, as described above, to have an array of holes 46 through the ballistic skin 18 that are spaced from the outer boundary edges 36 and positioned to assure that the ballistic skin 18 is capable of remaining secured to the existing door 11 during a gunfire attack. Also, as described above, the ballistic skin 18 may serve as a drilling template for drilling through-holes 50 through the existing door 11 that correspond to the array of holes 46 in the ballistic skin 18 . Once the through-holes 50 have been drilled, mechanical fasteners 32 may be secured through each hole of the array of holes 46 in the ballistic skin 18 and the corresponding through-holes 50 to secure the ballistic skin 18 to the non-threat side 15 of the existing door 11 . Also, in some exemplary embodiments, one mechanical fastener is secured through each hole of the plurality of holes 48 in the top ballistic skin clamp 20 and the bottom ballistic skin clamp 22 aligned with holes of the array of holes 46 and corresponding through-holes 50 to clamp the top ballistic skin clamp 20 and the bottom ballistic skin clamp 22 against the ballistic skin 18 .
[0048] Where the existing door 11 has an inset window 16 and the ballistic skin 18 has a window void 52 with a set of holes through the ballistic skin 18 , the installer may replace the inset window 16 with a ballistic window 24 having a size and shape to replace the inset window 16 . The ballistic window 24 is held in place by encasing the ballistic window 24 within a ballistic frame 26 comprised of an internal frame portion 28 with aligning holes 54 to align with the set of holes 51 in the ballistic skin 18 that surround the window void 52 and an external frame portion 30 with aligning holes 54 to align with the set of holes 51 in the ballistic skin 18 that surround the window void 52 . The ballistic window 24 is secured within the ballistic frame 26 by applying mechanical fasteners 32 through each aligned hole 54 and each aligned hole of the set of holes 51 to secure the ballistic frame 26 about the ballistic window 24 and to clamp the ballistic frame 26 against the ballistic skin 18 .
[0049] Additionally, the door latch 12 may be shielded against attack by securing latch guard 40 to the threat side 13 of the existing door 11 and securing a latch support 42 having a size greater than a latch void 56 in the ballistic skin 18 to the non-threat side 15 of the existing door 11 to cover the latch void 56 in an overlapping fashion.
[0050] While specific exemplary embodiments, methods, and applications of the present invention have been illustrated and described, it is to be understood that the invention is not limited to the precise configurations and components disclosed herein. Various modifications, changes, and variations which will be apparent to those skilled in the art may be made in the arrangement, operation, and details of the methods and systems disclosed herein without departing from the spirit and scope of the invention. | A ballistic door providing barrier-of-entry shielding blocks a doorway in certain emergency situations to shield against active shooters, while not inhibiting, impeding, or changing the safe egress through the ballistic door. A ballistic assembly may be secured to the non-threat side of an existing door, by retrofit installation or by new construction installation. The ballistic assembly has a ballistic skin, a top ballistic skin clamp, and a bottom ballistic skin clamp. The top and bottom ballistic skin clamps secure the ballistic skin against the non-threat side of the door. The ballistic door has at least a N.I.J. Level IIIA of protection against gunfire. | 4 |
[0001] This is a non-provisional application claiming priority to U.S. Provisional Application Ser. No. 60/601,410 filed Aug. 13, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of The Invention
[0003] Applicant's invention relates to a system and method for covering existing moldings around doorways and along walls and baseboard moldings in existing homes, and, more particularly, to a system and method for installing said system for attaching doorway overlay molding and baseboard encapsulate to existing doorway and baseboard molding. This system substantially improves the appearance of baseboard molding and molding around the doorways and walls by covering the existing molding with a more decorative molding. This system and method is user friendly such that an amateur or “do-it-yourself” person working alone can install these new molding designs with less costs and less frustration, and still create an expensive look. The examples presented are primarily for doors and are shown for purposes of illustration and not limitation. It is understood that this system and method could apply to other openings and architectural features such as baseboards, railings, stairs, windows, skylights, attic openings, etc.
[0004] 2. Background Information
[0005] In many homes, builders and general contractors generally use inexpensive type of trim around the doors and other openings, and along the floor. This molding is used to conceal imperfections that occur during the construction of the home around doorways and bases of walls, specifically where the wall meets the doorway or the floor. Because these walls and doorways have various corners, such as corners of doorways or corners where two walls meet, in order to install molding completely around a doorframe or where two walls meet and form an internal or external corner, it is necessary to cut the molding at various angles using a miter box so that the corners of the molding fit smoothly together around the corners. Furthermore, when the molding is installed, the molding is usually set back from the opening edge to form a reveal. This reveal is used to overcome the problems with trying to match flush edges. Wood moves and changes shape through the course of time. Because of this characteristic, it is impossible to get edges to stay flush when aligning molding to a doorway or wall. Stepping molding back to form reveals causes shadow lines and creates different planes that make it harder for the eye to pick up discrepancies. Creating this reveal when replacing molding so that the reveal is consistent and aesthetically pleasing is a complicated task. This molding is complicated and is usually installed by professionals.
[0006] Once the average consumer purchases a home, he/she may be inclined to change the standard trim used by the builder in favor of molding that is much more attractive and aesthetically pleasing. However, this creates a dilemma: Having spent a substantial amount of money in order to obtain the home, is the desire to upgrade the old molding around the doors and along the floor strong enough to justify spending even more money to have professionals come in and completely remove all the trim along the floor and around the doors and then install new trim? Additional expenses inevitably incur during this removal and installation process because of the difficulty of removing items that were intended by the builder to be permanent fixtures. Inherent in the removal process of the mold trim are damages in the forms of nicks, scrapes, dents, scratches, and even holes to the wall surface adjacent to the trim being removed. Furthermore, replacing molding does not merely consist of removing the old molding and attaching new molding. In addition to removing the old molding, one must clean the surfaces where the old molding left paint and caulk, measure and cut the new molding, sand and paint the new molding, align the new molding to insure that the corners align and the molding is square, and only then may the molding be attached to the wall or doorway surface. Even then the molding should be set back from the doorway or wall to form the reveal. This is an arduous process requiring a great deal of time and many tools, such as a hammer, a pry bar, nails, a hand saw, a miter box, a tape measure, and sanding and painting supplies, just to name a few. Furthermore, if great care is not taken, the consumer may well have to hire other professionals, such as painters or sheet-rockers, incurring an additional unanticipated expense in order to obtain the final upgraded “look” the consumer initially had in mind. The result is a costly renovation project.
[0007] The same concerns occur with the owner of an older home. In the course of time, the molding will become nicked, scraped, dented or scratched. This molding system allows the old molding to be covered with an upgraded more decorative molding with a minimum effort.
[0008] Obviously, most consumers are not in a position financially to undergo such a costly renovation shortly after purchasing their home or renovating an older home. Indeed, many consumers wait years before they may even consider such an expensive project. There are still others who, because of the cost and expense involved, remain complacent with their old molding.
[0009] There exists in the art the general concept of molding that would cover preexisting molding. Several patents relate to this field. These include: U.S. Pat. No. 871,028 to Brian; U.S. Pat. No. 2,887,739 to Bensman; U.S. Pat. No. 3,899,859 to Smith; U.S. Pat. No. 5,199,237 to Juntunen; U.S. Pat. No. 5,809,718 to Wicks; U.S. Pat. No. 6,021,619 to Mansson; U.S. Pat. No. 6,189,276 to Pinto, et al.; and U.S. Pat. No. 6,516,576 to Balmer. Of these patents, only Pinto, et al., come close to the present invention. However, as home owner's interest in “do-it-yourself” projects increase coupled with increasing costs of skilled labor, there still does not exist a system for the average consumer, working alone, to easily install and maintain aesthetically pleasing and attractive molding in their homes with a minimum of tools.
[0010] One problem “do-it-yourselfers” face include the need for precise measurement of corner pieces on the top corners of the doorframes and the left and right bottom portions of the doorframe as well as places where two walls meet in a corner to minimize any gaps or overlaps. Another is the skill involved in cutting these components using a specialized tool such as a miterbox. Yet another problem is the realistic notion that a “do-it-yourselfer” would most likely not have any assistance from other people during the project.
[0011] Although the Pinto patent teaches the general concept of having a new baseboard molding that is more decorative to cover inexpensive baseboard molding, this patent does not disclose or solve the problems encountered by the “do-it-yourself” homeowner previously discussed such that it minimizes or entirely eliminates the use of skilled craftsmen, complicated tools and machinery (such as a miterbox), and minimal assistance required. Additionally, none of the other patents mentioned overcome the disadvantages and problems associated with “do-it-self” door and base molding renovation projects. Nor do any present an integrated system to solve the problem created when one type of molding transitions into another, such as occurs at the bottom of a door when baseboard molding meets doorway molding, or where two walls meet to form an external or internal corner.
[0012] The present invention substantially improves and solves the problems discussed above because it can be completed by a single “do-it-yourself” homeowner without the use of professional craftsmen or complicated tools and machinery. The final result is a dramatically improved appearance of existing door, baseboard, and baseshoe molding over the currently installed molding. The use of this system and method thus now enable the average consumer and “do-it-yourself” homeowner to fully renovate all the door and baseboard moldings at less cost, less hassle, less frustration, and less time than would have previously been possible, and with a high degree of confidence in the results.
SUMMARY OF THE INVENTION
[0013] It is an object of the present invention to provide a molding that is applied over existing molding without the removal of the existing molding.
[0014] It is further an object of the present invention to provide a molding system that eliminates the need of a miter box to make angled cuts.
[0015] It is another object of the present invention to at least partially cover existing moldings.
[0016] It is another object of the present invention to cover existing molding of varying widths and thicknesses.
[0017] It is still further an object of the present invention to have a molding design that can be easily installed by the “do-it-yourselfer” market with very little effort, so there will be no need for the use of a miterbox to cut angles when installing this system.
[0018] It is another object of the present invention to use existing doorway molding as a base point for establishing a reveal.
[0019] It is yet another object of the present invention for such molding to be much more decorative in nature.
[0020] The miterless molding design system has three primary components: (a) overlay molding that follow along the doorways; (b) baseboard encapsulate that follow along the floors; and (c) corner blocks that seamlessly connect molding where the walls meet at an interior or exterior angle, or a corner is encountered around the doorway. The corner blocks eliminate any need for a miterbox to cut angles when installing the system. All the individual user has to do is cut the proper lengths of molding required. Recesses are cut into the backside of the corner blocks which allow the corner blocks to receive the old molding. With the corner blocks in place around the doorway, the overlay molding and baseboard encapsulate can attach to existing molding and be butted against the corner blocks, thus eliminating any need for angle cutting.
[0021] For dealing with moldings going around corners where two walls meet at an internal or external approximate right angle, a right angle block is used. A recess is cut into the right angle block in order to receive the existing baseboard at the internal corner. For dealing with moldings and walls forming corners where two walls meet at an external right angle, a right angle corner block with an additional recess is used to receive the exposed corner of the wall above the existing molding where the two walls meet.
[0022] By using the corner blocks and right angle blocks, right angles can be cut in every piece of molding for installation. If there are any openings at the corner blocks or right angle blocks, those openings between the molding and corner blocks would be calked. The design illustrated on the figures below are merely for illustrative purposes and not for limitation purposes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a front elevation view of an embodiment of the present invention.
[0024] FIG. 2 is a cross-sectional view of FIG. 1 along section lines 2 - 2 .
[0025] FIG. 3 is a cross-sectional view of FIG. 1 along section lines 3 - 3 .
[0026] FIG. 4 is a front elevation view of another embodiment of the present invention.
[0027] FIG. 5 is a perspective view of an upper corner block of the preferred embodiment of the present invention.
[0028] FIG. 6R is a perspective view of a right lower corner block of the preferred embodiment of the present invention.
[0029] FIG. 6L is a perspective view of a left lower corner block of the preferred embodiment of the present invention.
[0030] FIG. 7A is a perspective view of a right angle block for internal right angles of the preferred embodiment of the present invention.
[0031] FIG. 7B is a perspective view of a right angle corner block for external right angles of the preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0032] An embodiment of the present invention is illustrated in FIG. 1 . FIG. 1 is a front elevation view of a doorway 10 in a wall surface 12 that has a doorway overlay 14 therearound and a baseboard encapsulate 16 extending therefrom. The baseboard encapsulate 16 is abutted against the wall surface 12 and meets with a floor 20 .
[0033] A cross-sectional view of FIG. 1 along section lines 2 - 2 is depicted in FIG. 2 . The doorway overlay 14 attaches and thus covers the existing doorway molding 18 . A side edge 26 of the doorway overlay 14 aligns distantly from the doorway 10 . The recessed abutting inside portion 24 of the doorway overlay 14 is disposed over a length 130 of the existing doorway molding 18 and attaches along vertical and upper horizontal peripheral edges of the doorway 10 by a pair of vertical members (not shown). A corner formed by a wide end 126 and the length 130 of the existing doorway molding 18 is bedded into and recessed inside a corner 30 of the doorway overlay 14 . A small dead space 132 is created and enclosed by the wide end 126 of the existing doorway molding 18 , an angled inside portion 22 of the doorway overlay 14 , and the wall surface 12 . A small end 128 is aligned proximately to the doorway 10 . The new doorway overlay 14 includes an outer decorative surface 28 shown merely for illustrative purposes and not for limitation purposes.
[0034] Although the wide end 126 is described as embedded into the corner 30 of the doorway overlay 14 , it is understood that a typical spacer (not shown) could be inserted between the corner 30 and the wide end 126 to accommodate doorway moldings of different widths. In this configuration, the small end 128 of the doorway overlay 14 continues to be set back from the existing doorway molding 18 , exposing a small portion of the existing doorway 18 , forming a reveal.
[0035] A cross sectional view of FIG. 1 along section lines 3 - 3 , as seen in FIG. 3 , illustrates the existing baseboard 32 covered by the baseboard encapsulate 16 . An upper angled wall abutting portion 34 of the baseboard encapsulate 16 is fitted over a top surface 156 of the existing baseboard 32 . A recessed inside corner 36 gives room for thicker than normal existing baseboards. A recessed angled lower portion 38 of the baseboard encapsulate 16 allows the baseboard encapsulate 16 to accommodate existing baseboard 32 . A bottom surface 40 of the baseboard encapsulate 16 is flat and is disposed adjacent the floor 20 . A dead space 42 is created and defined by the recessed angled lower portion 38 of the baseboard encapsulate 16 , the floor 20 , the existing baseboard 32 , and the recessed inside corner 36 of the baseboard encapsulate 16 .
[0036] The baseboard encapsulate 16 and the doorway overlay 14 cover the existing baseboard 32 and the existing doorway molding 18 , respectively, and adhere the to wall surface 12 through a securing means such as a nail (not shown). In particular, it is preferable to use headless nails to minimize the nail's appearance on the baseboard encapsulate 16 . Headless nails may also be tapped into the molding for further concealment. Additionally, wood putty or other similar substance may be used to cover the nail entirely.
[0037] An alternative embodiment of the present invention is illustrated in FIG. 4 . In this figure, the baseboard encapsulate 16 is separated from the doorway overlay 14 by a lower left corner block 48 and a lower right corner block 50 . At the lower left hand side of the doorway 10 , the baseboard encapsulate 16 abuts a side edge 134 of the lower left corner block 48 . A bottom surface 136 is disposed adjacent the floor 20 . A top surface 76 joins the doorway overlay 14 . The doorway overlay 14 then continues upward in a longitudinal direction until it abuts a bottom surface 142 of the upper left corner block 46 . A side edge 144 of the upper left corner block 46 abuts the doorway overlay 14 which then extends in a latitudinal direction until it abuts the right upper corner block 150 at a side edge 146 . The doorway overlay 14 is then joined at a bottom surface 148 of the right upper corner block 150 and extends downward in a longitudinal direction to align with a lower right corner block 50 along a top surface 64 . A side edge 70 of the lower right corner block 50 then joins the baseboard encapsulate 16 . A bottom surface 138 of the lower right corner block 50 is disposed adjacent the floor 20 .
[0038] The upper corner blocks 46 and 150 are used in the upper left and right corners of the doorframe. Their use eliminates the need to make angle cuts other than perpendicular cuts in order for the doorway overlay 14 to join together at the corners. A more detailed description of the upper left corner block 46 and the upper right corner block 150 follows.
[0039] FIG. 5 shows A backside 52 of the upper corner block 46 . Although the numbering for the corner blocks for FIG. 4 differentiated an upper left corner block 46 from the upper right corner block 150 , the corner blocks are identically designed so as to be able to be used with either the left or right upper corner; the only difference being its orientation. The use of different numbers for the upper left and right corner blocks in FIG. 4 was merely for convenience. Therefore both the upper left and upper right corner blocks are from here forward described as the upper corner block 46 . The backside 52 of the upper corner 46 rests against the wall surface 12 . A recess 54 is cut into the back side 52 of the upper corner block 46 . The cut is made at an angle 140 . This angle 140 then can be fixed snuggly over the inward angle (not shown) of the existing doorway molding 18 . A recessed edge 60 and a recessed edge 62 wrap snuggly around the corners of the existing doorway molding 18 . The bottom surface 142 and a side edge 58 then become the receiving surfaces for the doorway overlay 14 . The doorway overlay 14 then extends downward in a longitudinal direction until it aligns with either the lower left corner block 48 or the lower right corner block 50 . The lower left corner block 48 and the lower right corner block 50 are similarly designed, but accommodate the doorway overlay 14 and the baseboard encapsulate 16 as detailed below.
[0040] Referring now to FIG. 6L , a wall abutting surface 82 of the lower left corner block 48 rests against the wall surface 12 . A second recess 86 cut therein allows the existing baseboard 32 to be received therein. The baseboard encapsulate 16 then fits over the existing baseboard 32 and abuts the lower left corner block 48 along the side edge 134 . A side edge 84 faces the doorway 10 . A first recess 78 cut therein receives the existing doorway molding 18 . The existing doorway molding 18 is further secured by an inside corner 80 . The first recess 78 is cut at an angle 152 in order to accommodate the angles typically associated with existing doorway molding. The doorway overlay 14 connects with the lower left corner block 48 along the top surface 76 , while the bottom surface 136 is disposed adjacent the floor 20 .
[0041] Referring to the lower right corner block 50 , as depicted in FIG. 6R , a wall abutting surface 68 rests against the wall surface 12 . A second recess 72 cut therein receives the existing baseboard 32 therein. A first recess 66 cut therein receives the existing doorway molding 18 therein. The first recess 66 is cut at an angle 154 in order to accommodate the angles typically associated with existing doorway molding. The existing doorway molding 18 resting inside the first recess 66 is further secured by an inside corner 88 . The baseboard encapsulate 16 covering the existing baseboard 32 couples to the lower right corner block 50 along a side edge 70 . A side edge 74 faces toward the doorway 10 . The doorway overlay 14 aligns with the lower right corner block 50 at the top surface 64 , while the bottom surface 138 is disposed adjacent the floor 20 .
[0042] The concept of blocks placed over corners may also be used where two wall surfaces meet, creating an internal or external corner. FIG. 7A illustrates a right angle block 90 . The right angle block 90 is used when two wall surfaces meet perpendicularly at substantially internal right angles to each other. The right angle block 90 is positioned such that a recess, formed by a surface 100 and a surface 102 cut therein receives the existing baseboard 32 . The baseboard encapsulate 16 is placed over the existing baseboard 32 and abuts the right angle block 90 at a side edge 96 and a side edge 98 . A bottom surface 104 of the right angle block 90 is adapted to be positioned adjacent the floor 20 . An outside decorative surface 94 is also included on the right angle block 90 , while a top surface 92 remains unobstructed.
[0043] A similar design is used when two walls meet at substantially perpendicularly external right angles to each other, forming an external corner. FIG. 7B illustrates a right angle block 106 with a recess, formed by a surface 120 and a surface 122 cut therein, to receive the existing doorway molding 18 . Additionally, a second recess defines a first surface 112 and a second surface 114 , and is adapted to receive a portion of the wall corner disposed above the existing baseboard 32 . The baseboard encapsulate 16 abuts the right angle block 106 along a side edge 116 and a side edge 118 . A bottom surface 124 is adapted to be positioned adjacent the floor 20 , while a top surface 108 remains free from obstruction. The right angle block 106 also includes an outside decorative surface 110 (similar to the outside decorative surface 94 for the inside lower corner block 90 ). Thus, after installation, the right angle block 90 covers the existing baseboard 32 and abuts the baseboard encapsulate 16 at internal corners. Similarly, after installation, the right angle block 106 covers the existing baseboard 32 and abuts the baseboard encapsulate 16 at external corners. | A molding system and method for installation that covers existing molding. The molding system covers existing trim for doorways and floors with a more decorative molding. The invention includes a molding overlay. An upper corner block covers the intersections of the existing doorway molding, and a lower corner block covers a section of the existing doorway molding with the existing baseboard, eliminating the need to cut mitered angles in the overlay molding. Recesses in the backside of the corner blocks allow the corner blocks to receive the old molding. The molding overlay abuts the corner blocks, thereby avoiding the requirements for making any cuts other than perpendicular cuts. | 4 |
FIELD OF THE INVENTION
The present invention relates to an optical pulse reflectometer.
RELATED TECHNOLOGY
The ongoing establishment and expansion of optical fiber networks calls for the use of suitable optical measuring instruments during installation, for maintenance purposes and for the monitoring thereof. A particularly important measuring instrument in this connection is the optical pulse reflectometer, known also as the optical time-domain reflectometer (OTDR). Such a measuring instrument is used to measure and evaluate reflections in optical fiber transmission systems. Reflections occur in optical components, such as in a light-conducting fiber, principally because of points of sudden irregularity in the refractive index, for example at the end of the fiber, and as a result of Rayleigh scattering, caused by inhomogeneities of the fiber. Further examples of reflecting optical components are connectors, junctions and splices. In a known optical pulse reflectometer, the pulses emitted by a laser diode are supplied via a static or passive power splitter to the fiber to be measured. The static power splitter, known also as a beam splitter, may be in the form of a semi-opaque reflector, an optical fiber 2×2 coupler (known also as a directional coupler) or a 2:1 coupler, i.e., an inversely operated Y-junction. The function of the passive beam splitter is to change the propagation direction of the light pulse, i.e., to direct the light pulses spatially. The latter is necessary to ensure that the optical signal components, reflected by the fiber due to Rayleigh and/or Fresnel scattering, are directed onto a photodetector. However, the passive beam splitter has the disadvantage that approximately only half of the reflected signal component is returned to the photodetector. The other half of the reflected signal component is directed in an undesired manner towards the laser diode, with the consequence that an optical isolator must be additionally connected upstream from the laser diode to protect against the undesired reflections.
Furthermore, the reflected light component is additionally attenuated by inevitable imperfections in the fiber connections. If, instead of an inversely operated Y-branch, passive 2×2 couplers or semi-opaque reflectors are used, it is even so that only about one fourth of the light intensity emitted by the laser diode is utilized. In other words, the signal emitted by the laser diode is attenuated by a factor of 4 before it reaches the photodetector.
German Patent Application No. A-4 437 821 describes a shielding device for an optical time-domain reflectometer, also known as an OTDR, which uses a high-speed switch and a pumped light source for producing optical pulses. The essential function of the high-speed switch is to selectively block a frequency range of the light reflected by the fiber to be measured, the light also being described as Fresnel-reflected light. To achieve this, the optical high-speed switch is operated synchronously with the optical pulse produced by the light source.
U.S. Pat. No. 5,388,172, describes an optical switching device for an OTDR, where a pulsed laser and an optical receiver are connected to a fiber to be measured. The optical switching device performs the function of keeping the Fresnel reflections from the fiber away from the optical receiver.
European Patent Application No. A 0 502 422 describes an optical time-domain reflectometer, in which a Raman laser device and an optical detector are connected via an optical switch to the fiber to be measured. To be able to measure the loss properties of the optical fiber at any wavelength at all, within a broad spectrum, a Raman scattered-light pulse is used. For this, the Raman laser device uses a solid-state laser, which is pumped by a laser diode to produce a light pulse.
The International Patent Application having International Publication No. WO-A 91 12509 describes an OTDR which uses a pulsed laser to produce light pulses. The pulsed laser and an optical receiver are connected via a passive optical coupler to a fiber to be measured.
In the essay, “A Low Crosstalk and Polarization Independent Optical Waveguide Switch for OTDR”, NEC Research and Development, no. 99, October 1990, Tokyo, Japan, pp. 75-83, XP000178479, H. Kawashima et al. describe an optical waveguide switch for an OTDR that works with a wavelength of 1.3 μm, with a Ti:LiNbO 3 waveguide. As a light source, a laser diode is used, in turn, which produces light pulses.
SUMMARY OF THE INVENTION
An object of the present invention, therefore, is to further develop the optical pulse reflectometer described at the outset so as to enable the circuit expenditure and, thus, the costs to be reduced by eliminating the need for synchronization between the light source and the control device used for switching the optical switch.
The object of the invention, therefore, is to further develop the initially described optical pulse reflectometer in such a manner that its sensitivity can be improved without increasing the optical transmitting power of the light source and such that it is not necessary to employ an additional optical isolator to protect the light source from reflections.
The optical pulse reflectometer according to the present invention includes at least one—generally known—optical switch for selectively connecting of a light source, particularly a laser diode, to an associated test object and for the selectively connecting to the test object to an associated photodetector. The optical switch is switched, for example, by a control device which switches the optical switch at predetermined points in time. In this manner, the optical transmitting power of the light source is injected virtually without loss of power into the test object, in particularly an optical fiber, and that the light reflected in the test object is subsequently supplied virtually unattenuated to the photodetector. Thus, without having to actually increase the optical transmitting power of the light source, it is possible, inter alia, to test fibers over greater lengths than in known methods heretofore using static power splitters. In addition, for a measured distance of a given length, it is possible to employ shorter light pulses, thereby enhancing the spatial resolution of the measurement. Since, compared, for example, to passive 2×2 couplers or semi-opaque reflectors, an optical switch allows approximately four times the power utilization, the pulse duration for detecting Rayleigh scattering can be reduced to one fourth. (Note that the intensity of the Rayleigh scattering is a function of the energy (light intensity×pulse duration) of the pulse.) For OTDR measurements, this means that significant points on the fiber can be located with greater accuracy. Consequently, for example, faults on a fiber cable can be pinpointed with suitable accuracy. Due to the higher signal level, Fresnel reflections also produce correspondingly stronger echo signals in the photodetector, which are, therefore, also able to be detected with greater sensitivity. In contrast to a conventional optical pulse reflectometer, the optical switch virtually eliminates the need for an optical isolator for protecting the light source from reflections. This is due to the fact that virtually all of the reflected signal component is directed to the photodetector.
The optical switch used may, for example, be a 2×2 directional coupler or an acoustooptic modulator, both of which are in effect known. An example of a switchable optical 2×2 directional coupler is the thermooptically controlled coupler, described by Norbert Keil in the essay “Optische Schalter aus Kunststoff—Schlüsselkomponenten in den Telekom-Netzen der Zukunft” [ Optical switches made of plastic—Key components in the telecom networks of the future ], ntz, issue December 1995, pages 36-41. As a light source, the optical pulse reflectometer uses a light source operated in constant light mode, the switchable optical switch also being used to produce light pulses. In this case, the pulse frequency and pulse duration of the light pulses is stipulated by a control device which by drives the optical switch accordingly. Operating a light source in a constant light mode has many advantages over an operation with a pulsed light source. The need is eliminated for synchronization between the light source and the control device used for switching over the optical switch. In addition, the voltage spikes produced by an electrical pulse generator can no longer have an adverse effect on the light source. Moreover, more modest time requirements can be placed on the light source with respect to a fast modulation for producing short enough pulses.
To ensure that all the reflections produced by the test object are directed to the photodetector and can, thus, be evaluated by the optical pulse reflectometer, the optical test pulse must have completely propagated through the optical switch before the switch can be switched. This is achieved by a launching fiber of predetermined length which is connected between the optical switch and the test object. The length of the launching fiber must be 1≧cT, where c is the speed of the light in the launching fiber and T is the longest pulse duration of a pulse which can be emitted from the optical pulse reflectometer. Consequently, the launching fiber acts as a delay line for the reflected light pulses.
To prevent light reflections produced by the unused connection of the optical switch from being reflected the light source or radiation produced by the same from being radiated to the ambient environment, the unused connection of the optical switch is terminated with an absorber and an optical shield. In the case of a 2×2 coupler, the absorber may be formed from a plurality of very narrow turns (having a diameter of a few mm) of the fiber section that is not terminated. Suitable plastic sleeves may be used as shielding.
Connected in known manner between the photodetector and a display device is a data preparation device, which includes a known Boxcar averager, as well as a logarithm converter.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the present invention is explained in greater detail in conjunction with the appended drawings, in which:
FIG. 1 shows a greatly simplified block diagram of an optical pulse reflectometer according to the present invention;
FIG. 2 shows a switchable optical 2×2 directional coupler in the straight-ahead state for use in the optical pulse reflectometer according to FIG. 1; and
FIG. 3 shows the switchable optical 2×2 directional coupler presented in FIG. 2 in the crossed-over state.
DETAILED DESCRIPTION
FIG. 1 shows an optical pulse reflectometer, known also as an optical time-domain reflectometer (OTDR). The pulse reflectometer, identified in general with the reference numeral 10 , includes a generally known pulse generator 20 , the pulse generator 20 being tunable with respect to pulse duration and wavelength and driving, for example, a laser diode 30 . Connected downstream from laser diode 30 is a switchable optical switch 40 , which is switched over in response to switching signals produced by a control device (not shown). In the example described herein, switch 40 is a 2×2 directional coupler, as shown in FIGS. 2 and 3, which can be switched by means of an electric voltage. The 2×2 directional coupler 40 , which is available, for example, in integrated optical design, includes two light conducting strands 41 and 43 disposed at a predetermined distance from each other. In a middle region 49 , the two strands 41 and 43 come so close to each other that the 2×2 directional coupler can be selectively switched. Depending on the physical controlled variable, the 2×2 directional coupler is either in the straight-ahead state (see FIG. 2) or in the crossed-over state (see FIG. 3 ). On the side pointing to laser diode 30 , strand 41 has a port 42 , used as an input, and, on the opposite side, a port 44 , used both as an output and also as an input. On the side pointing to laser diode 30 , strand 43 has a port 46 , acting as an output, and on the opposite side, an unused port 48 . To prevent light pulses from being reflected to laser diode 30 or being radiated to the ambient environment, port 48 may be terminated with a shield and an absorber (not shown). The absorber may be formed from a plurality of very narrow turns of the fiber section of strand 43 , on which port 48 is located. The optical test pulses produced by laser diode 30 are injected into input port 42 of strand 41 . Port 44 of strand 41 is connected to a launching fiber 50 . Connected to launching fiber 50 is a test object, particularly an optical fiber 60 , referred to in the following as a test fiber. A photodetector 70 is connected to output port 46 of strand 43 of the 2×2 directional coupler 40 . Photodetector 70 is, for example, a photodiode (e.g., an avalanche photo diode—APD). Photodiode 70 converts the optical echo pulse received through output port 46 into an electric signal. Photodiode 70 is connected on the output side to a data evaluation device 80 containing a generally known Boxcar averager and a logarithm converter. The purpose of the data evaluation device 80 is to process a plurality of received echo pulses into an amplified and easily displayable signal. The output of data evaluation device 80 is connected to the first input of an oscilloscope 90 on which the echo pulses produced in test fiber 60 are displayed. Connected to the second input of oscilloscope 90 is pulse generator 20 which synchronizes oscilloscope 90 to laser diode 30 .
The following briefly explains the operating principle of optical pulse reflectometer 10 according to the present invention.
As shown in FIG. 1, the light pulses emitted by laser diode 30 are directed via input port 42 of the 2×2 directional coupler to output port 44 . The 2×2 directional coupler 40 must, for the duration of each test pulse, be switched in such a manner that the entire light signal leaves the 2×2 directional coupler 40 at output port 44 and is injected more or less without loss into test fiber 60 . For this purpose, the 2×2 directional coupler 40 is switched to the “straight-ahead” state, as shown in FIG. 2 . Immediately after the light pulse has completely propagated through strand 41 , the 2×2 directional coupler 40 is switched to the crossed-over state, as shown in FIG. 3 . In this state, the reflection signal caused by test fiber 60 and delayed in launching fiber 50 is transferred via port 44 (now acting as an input) of strand 41 to the other strand 43 . The reflection signal leaves the 2×2 directional coupler 40 at port 46 and is directed to photodetector 70 . To ensure that all the test pulses reflected by test fiber 60 are passed to photodiode 70 and can be evaluated by optical pulse reflectometer 10 , the test pulse must have completely passed through the 2×2 directional coupler 40 before the 2×2 directional coupler 40 can be switched from the straight-ahead state to the crossed-over state. For this purpose, launching fiber 50 is inserted between the optically switchable 2×2 coupler 40 and the test fiber 60 . Launching fiber 50 delays the echo pulse until the 2×2 directional coupler 40 has been switched. The length of launching fiber 50 should therefore be 1≧cT, where c is the speed of the light in launching fiber 50 and T is the longest pulse duration of a pulse which can be emitted by laser diode 30 . Usually, the duration of a light pulse emitted by laser diode 30 will be 10 ns to 10 μs. The mark-to-space ratio is, for example, approximately 1:1000. In this manner, each echo pulse reaches photodetector 70 as an undistorted pulse and can be used to measure the attenuation and reflection profile of test fiber 60 , and can be displayed on oscilloscope 90 . Furthermore, the use of launching fiber 50 makes it possible to reliably prevent any light components reflected in the test fiber 60 from being returned to laser diode 30 .
Instead of pulsed laser diode 30 , it is also possible to employ a laser diode which is operated in constant light mode, light pulses being produced in this case in the optical switch. In the case of the described 2×2 coupler 40 , the constant light of laser diode 30 is, for this purpose, for the duration of a test pulse, directed in the straight-ahead state to test fiber 60 . After the desired pulse duration, stored, for example, in the control device, comes to an end, the 2×2 coupler 40 is switched to the crossed-over state. The constant light, still emitted by laser diode 30 , is directed to port 48 and is more or less completely attenuated in the connected absorber. At the same time, the light reflected by test fiber 60 because of Rayleigh scattering and Fresnel reflections is directed to photodetector 70 and is then, as already described, processed and displayed.
The improved power utilization of optical pulse reflectometer 10 according to the present invention is accomplished in that, on both the outward and return travel of a pulse, by suitably selecting the instant of switching of optical switch 40 , there are no longer any structural, i.e., process-induced, power losses, as is the case with static power splitters. Consequently, the entire optical power received at a port of the 2×2 coupler 40 is switched through more or less unattenuated to only one port at a time on the opposite side. This is true both when the test pulse is emitted and also when the reflected components are returned.
The controlled or adjusted variable in currently common and technically well-controlled versions of switchable 2×2 directional couplers is very often an electric voltage. The therewith associated electric field permits the use of the Pockels effect (linear electro-optical effect). Switchable optical 2×2 directional couplers can be implemented in integrated optical design in a variety of versions (waveguide structure-material composition). Furthermore, there is the possibility of monolithic integration with laser diode 30 of optical pulse reflectometer 10 . An alternative embodiment of a switchable optical switch for the free-beam guiding of the light may include a plate, which is coated on both sides and whose reflectivity can, for example, be electrically adjusted between virtually full transparency during the emission of the test pulse and virtually complete reflection during the reception of the reflections from test fiber 60 . | An optical pulse reflectometer includes switch for selectively connecting a light source to an associated test object and for selectively connecting the test object to an associated photodetector ( 70 ). The power utilization and thus the sensitivity is improved over conventional optical pulse reflectometers. | 6 |
[0001] This application is a continuation of International Application No. PCT/JP02/09306, filed Sep. 11, 2002, entitled “Adaptive Filtering Based upon Boundary Strength,” invented by Shijun Sun, Shawmin Lei and Hiroyuki Katata, now published under International Publication No. WO 03/026313; which is a continuation of U.S. patent application Ser. No. 09/953,329, filed Sep. 14, 2001, entitled “Adaptive Filtering Based upon Boundary Strength,” invented by Shijun Sun and Shawmin Lei.
BACKGROUND OF THE INVENTION
[0002] Block based motion compensated video coding is used in many video compression standards, such as for example, H.261, H.263, H.263+, MPEG-1, MPEG-2, and H26L. Block based motion compensation encodes video pixels in a block by block manner using image compression techniques. The image compression techniques normally use lossy compression techniques that result in visual artifact in the decoded images, referred to generally as image artifacts. One type of image artifacts are blocking artifacts that occur along the block boundaries in a reconstructed image. The primary source of the blocking artifacts result from coarse quantization of transform coefficients used to encode the blocks.
[0003] Reconstructed images are the images produced after the blocks are inverse transformed and decoded. Image filtering techniques may be used to reduce the artifacts in reconstructed images. The rule of thumb for these image filtering techniques is that image edges should be preserved while the rest of the image should be smoothed. A low pass filter may be used as the image filter and its characteristics should be selected based on the characteristics of a particular pixel or set of pixels surrounding the image edges.
[0004] Non-correlated image pixels that extend across image block boundaries are specifically filtered to reduce blocking artifacts. While filtering techniques reduce blocking artifacts, however, these filtering techniques may unfortunately introduce blurring artifacts into the image. For example, if there are few or no blocking artifacts present between adjacent blocks, then the low pass filtering needlessly incorporates blurring into the image while at the same time wasting processing resources.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] [0005]FIG. 1 is a diagram showing how deblock filtering is selectively skipped according to similarities between adjacent image blocks.
[0006] [0006]FIG. 2 is a diagram showing two adjacent image blocks having similar motion vectors.
[0007] [0007]FIG. 3 is a diagram showing how transform coefficients are identified for one of the image blocks.
[0008] [0008]FIG. 4 is a diagram showing how residual transform coefficients are compared between two adjacent image blocks.
[0009] [0009]FIG. 5 is a block diagram showing how the video image is encoded and decoded.
[0010] [0010]FIG. 6 is a block diagram showing how deblock filtering is selectively skipped in a codec.
[0011] [0011]FIG. 7 is a representation of an existing block based image filtering technique.
[0012] [0012]FIG. 8 is a block diagram showing a technique for determining the boundaries to filter and the strength of the respective filter to use.
[0013] [0013]FIG. 9 is a drawing for explaining other embodiments of the present invention
[0014] [0014]FIG. 10 is a drawing for explaining further embodiments of the present invention.
[0015] [0015]FIG. 11 is a drawing for explaining further embodiments of the present invention.
[0016] [0016]FIG. 12 is a drawing for explaining further embodiments of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Conventional filtering processes consider a single reconstructed image frame at a time. Block based video encoding techniques may use motion vectors to estimate the movement of blocks of pixels. The motion-vector information is available at both the encoder and decoder but is not used with conventional filtering processes. For example, if two adjacent blocks share the same motion vector with respect to the same reference image frame, (for a multiple reference frames system) there is likely no significant difference between the image residuals of each block and accordingly should not be filtered. In essence, adjacent portions of the image have the same motion with respect to the same reference frame and accordingly no significant difference between the image residuals would be expected. In many cases, the block boundary of these two adjacent blocks may have been filtered in the reference frame and should therefore not be filtered again for the current frame. If a deblock filter is used without considering this motion-vector information, the conventional filtering process might filter the same boundary again and again from frame to frame. This unnecessary filtering not only causes unnecessary blurring but also results in additional filter computations.
[0018] [0018]FIG. 1 illustrates an image 12 that selectively filters blocking artifacts according to similarities between image blocks. It is to be understood that the image may likewise use non-square blocks or any other sets of pixels. The borders between some of the blocks 14 include blocking artifacts 18 . In general blocking artifacts are any image discontinuities between blocks 14 that may result from the encoding and/or decoding process. A low pass filter or other filter may be used to reduce the blocking artifacts that exist at the borders of adjacent image blocks.
[0019] For example, blocking artifacts 24 exist between blocks 20 and 22 . A low pass filter may be used at the border 26 between blocks 20 and 22 to remove or otherwise reduce the blocking artifacts 24 . The low pass filter, for example, selects a group of pixels 28 from both sides of the border 26 . An average pixel value, or any other statistical measure, is derived from the group of pixels 28 . Then each individual pixel is compared to the average pixel value. Any pixels in group 28 outside of a predetermined range of the average pixel value is then replaced with the average pixel value.
[0020] As previously described, if there are few or no blocking artifacts 24 between the adjacent pixels, then the groups of pixels 28 may be needlessly filtered causing blurring in the image. A skip mode filtering scheme may use the motion estimation and/or compensation information for adjacent image blocks as a basis upon which to selectively filter. If the motion estimation and compensation information is sufficiently similar the filtering may be skipped. This avoids unnecessary image blurring and significantly reduces the required number of filtering operations, or any other appropriate value.
[0021] As an example, it may be determined during the encoding process that adjacent image blocks 30 and 32 have similar coding parameters. Accordingly, the deblock filtering may be skipped for the groups of pixels 34 that extend across the border 31 between adjacent blocks 30 and 32 . Skip mode filtering can be used for any horizontal, vertical, or otherwise any boundary between adjacent blocks in the image 12 .
[0022] [0022]FIG. 2 illustrates a reference frame 42 , reference frame 48 , and a current frame 40 that is currently being encoded or decoded. The coding parameters for blocks 44 and 46 are compared to determine whether the deblock filtering should be skipped between the two adjacent blocks 44 and 46 . One of the encoding parameters that may be compared is the motion vectors (MV) for the blocks 44 and 46 .
[0023] A motion vector MV 1 points from block 44 in the current image frame 40 to an associated block 44 ′ in the reference image 42 . A motion vector MV 2 points from block 46 in the current image frame 40 to an associated block 46 ′ in the reference frame 42 . A skip mode filtering checks to see if the motion vectors MV 1 and MV 2 point to adjacent blocks in the same reference frame 42 . If the motion vectors point to adjacent blocks in the same reference frame (MV 1 =MV 2 ), then the deblock filtering may be skipped. This motion vector information may be used along with other coding information to decide whether to skip deblock filtering between the two image blocks 44 and 46 .
[0024] More than one reference frame may be used during the encoding and decoding process. For example, there may be another reference frame 48 . The adjacent blocks 44 and 46 may have motion vectors pointing to different reference frames. In one example, the decision to skip deblock filtering depends on whether the motion vectors for the two adjacent blocks point to the same reference frame. For example, image block 44 may have a motion vector 49 pointing to reference frame 48 and image block 46 may have the motion vector MV 2 pointing to reference frame 42 . The deblock filtering is not skipped in this example because the motion vectors 49 and MV 2 point to different reference frames.
[0025] [0025]FIG. 3 illustrates another example of a coding parameter that may be used to decide whether or not to selectively skip deblock filtering. The image block 44 from image frame 40 is compared with reference block 44 ′ from the reference frame 42 pointed to by the motion vector MVl as previously illustrated in FIG. 2. A residual block 44 ″ is output from the comparison between image block 44 and reference block 44 ′. A transform 50 is performed on the residual block 44 ″ creating a transformed block 44 ″ of transform coefficients. In one example, the transform 50 is a Discrete Cosine Transform. The transformed block 44 ″ includes a D.C. components 52 and A.C. components 53 .
[0026] The D.C. component 52 refers to a lowest frequency transform coefficient in image block 44 . For example, the coefficient that represents the average energy in the image block 44 . The A.C. components 53 refer to the transform coefficients that represent the higher frequency components in the image block 44 . For example, the transform coefficients that represent the large energy differences between pixels in the image block 44 .
[0027] [0027]FIG. 4 illustrates the transformed residual blocks 44 ″ and 46 ″. The D.C. components 52 from the two transformed blocks 44 ″ and 46 ″ are compared in processor 54 . If the D.C. components are the same or within some range of each other, the processor 54 notifies a deblock filter operation 56 to skip deblock filtering between the border of the two adjacent blocks 44 and 46 . If the D.C. components 52 are not similar, then no skip notification is initiated and the border between blocks 44 and 46 is deblock filtered.
[0028] In one example, the skip mode filtering may be incorporated into the Telecommunications Sector of the International Telecommunication Union (ITU-T) proposed H.26L encoding scheme. The H.26L scheme uses 4×4 integer Discrete Cosine Transform (DCT) blocks. If desired, only the D.C. component of the two adjacent blocks may be checked. However some limited low frequency A.C. coefficients may likewise be checked, especially when the image blocks are larger sizes, such as 9×9 or 16×16 blocks. For example, the upper D.C. component 52 and the three lower frequency A.C. transform coefficients 53 for block 44 ″ maybe compared with the upper D.C. component 52 and three lower frequency A.C. transform coefficients 53 for block 46 ″. Different combinations of D.C. and/or any of the A.C. transform coefficients can be used to identify the relative similarity between the two adjacent blocks 44 and 46 .
[0029] The processor 54 can also receive other coding parameters 55 that are generated during the coding process. These coding parameters include the motion vectors and reference frame information for the adjacent blocks 44 and 46 as previously described. The processor 54 may use some or all of these coding parameters to determine whether or not to skip deblock filtering between adjacent image blocks 44 and 46 . Other encoding and transform functions performed on the image may be carried out in the same processor 54 or in a different processing circuit. In the case where all or most of the coding is done in the same processor, the skip mode is simply enabled by setting a skip parameter in the filtering routine.
[0030] [0030]FIG. 5 shows how skip mode filtering may be used in a block-based motion-compensated Coder-Decoder (Codec) 60 . The codec 60 is used for inter-frame coding. An input video block from the current frame is fed from box 62 into a comparator 64 . The output of a frame buffering box 80 generates a reference block 81 according to the estimated motion vector (and possible reference frame number). The difference between the input video block and the reference block 81 is transformed in box 66 and then quantized in box 68 . The quantized transform block is encoded by a Variable Length Coder (VLC) in box 70 and then transmitted, stored, etc.
[0031] The encoding section of the codec 60 reconstructs the transformed and quantized image by first Inverse Quantizing (IQ) the transformed image in box 72 . The inverse quantized image is then inverse transformed in box 74 to generate a reconstructed residual image. This reconstructed residual block is then added in box 76 to the reference block 81 to generate a reconstructed image block. Generally the reconstructed image is loop filtered in box 78 to reduce blocking artifacts caused by the quantization and transform process. The filtered image is then buffered in box 80 to form reference frames. The frame buffering in box 80 uses the reconstructed reference frames for motion estimation and compensation. The reference block 81 is compared to the input video block in comparator 64 . An encoded image is output at node 71 from the encoding section and is then either stored or transmitted.
[0032] In a decoder portion of the codec 60 , a variable length decoder (VLD) decodes the encoded image in box 82 . The decoded image is inverse quantized in box 84 and inverse transformed in box 86 . The reconstructed residual image from box 86 is added in the summing box 88 to the reference block 91 before being loop filtered in box 90 to reduce blocking artifacts and buffered in box 92 as reference frames. The reference block 91 is generated from box 92 according to the received motion vector information. The loop filtered output from box 90 can optionally be post filtered in box 94 to fuirther reduce image artifacts before being displayed as, a video image in box 96 . The skip mode filtering scheme can be performed in any combination of the filtering functions in boxes 78 , 90 and 94 .
[0033] The motion estimation and compensation information available during video coding are used to determine when to skip deblock filtering in boxes 78 , 90 and/or 94 . Since these coding parameters are already generated during the encoding and decoding process, there are no additional coding parameters that have to be generated or transmitted specially for skip mode filtering.
[0034] [0034]FIG. 6 shows is further detail how skip mode filtering may be used in the filters 78 , 90 , and/or 94 in the encoder and decoder in FIG. 5. The interblock boundary between any two adjacent blocks “i” and “k” is first identified in box 100 . The two blocks may be horizontally or vertically adjacent in the image frame. Decision box 102 compares the motion vector mv(j) for block j with the motion vector mv(k) for block k. It is first determined whether the two adjacent blocks j and k have the same motion vector pointing to the same reference frame. In other words, the motion vectors for the adjacent blocks point to adjacent blocks (mv(j)=mv(k)) in the same reference frame (ref(j)=ref(k)).
[0035] It is then determined whether the residual coefficients for the two adjacent blocks are similar. If there is no significant difference between the image residuals of the adjacent blocks, for example, the two blocks j and k have the same of similar D.C. component (dc(j) dc(k)), then the deblock filtering process in box 104 is skipped. Skip mode filtering then moves to the next interblock boundary in box 106 and conducts the next comparison in decision box 102 . Skip mode filtering can be performed for both horizontally adjacent blocks and vertically adjacent blocks.
[0036] In one embodiment, only the reference frame and motion vector information for the adjacent image blocks are used to determine block skipping. In another embodiment, only the D.C. and/or A.C. residual coefficients are used to determine block skipping. In another embodiment, the motion vector, reference frame and residual coefficients are all used to determine block skipping.
[0037] The skip mode filtering scheme can be applied to spatially subsampled chrominance channels. For example in a case with 4:2:0 color format sequences, skip mode filtering for block boundaries may only rely on the equality of motion vectors and D.C. components for the luminance component of the image. If the motion vectors and the D.C. components are the same, deblock filtering is skipped for both the luminance and chrominance components of the adjacent image blocks. In another embodiment, the motion vectors and the D.C. components are considered separately for each luminance and chrominance component of the adjacent blocks. In this case, a luminance or chrominance component for adjacent blocks may be deblock filtered while the other luminance or chrominance components for the same adjacent blocks are not deblock filtered.
[0038] Referring to FIG. 7, a technique recently proposed by others in H.26L defines a “block strength” parameter for the loop filter to control the loop filtering process. Each block of an image has a strength value that is associated with the block and controls the filtering performed on all of its four block boundaries. The block strength value is derived based on the motion vectors and the transform coefficients available in the bitstream. However, after consideration of the use of the block strength value for all four edges of the block, the present inventors came to the realization this results in removing some blocking artifacts at some edges while blurring along other edges.
[0039] In contrast to the block by block manner of filtering, the present inventors came to the realization that filtering determinations should be made in an edge by edge manner together with other information. The other information, may include for example, information related to intra-block encoding of blocks, information related to motion estimation of blocks with residual information, information related to motion estimation of blocks without residual information, and information related to motion estimation of blocks without residuals having sufficient differences, information related to reference frames, and information related to motion vectors of adjacent blocks. One, two, three, or four of these information characteristics may be used to improved filtering abilities in an edge by edge manner. Based upon different sets of characteristics, the filtering may be modified, as desired.
[0040] For each block boundary a control parameter is preferably defined, namely, a boundary strength Bs. Referring to FIG. 8 a pair of blocks sharing a common boundary are referred to as j and k. A first block 200 checks to see if either one of the two blocks is intra-coded. If either is intra-coded then the boundary strength is set to three at block 202 . Block 200 determines if both of the blocks are not motion predicted. If no motion prediction is used then the block derives from the frame itself and accordingly there should be filtering performed on the boundary. This is normally appropriate because intra-coded block boundaries normally include blocking artifacts.
[0041] If both of the blocks j and k are, at least in part, predicted from a previous or future frame, then the blocks j and k are checked at block 204 to determine if any coefficients are coded. The coefficients, may be for example, discrete cosine transform coefficients. If either of the blocks j and k include non-zero coefficients, then at least one of the blocks represent a prediction from a previous or future frame together with modifications to the block using the coefficients, generally referred to as residuals. If either of the blocks j and k include non-zero coefficients (and motion predicted) then the boundary strength is set to two at block 206 . This represents an occurrence where the images are predicted but the prediction is corrected using a residual. Accordingly, the images are likely to include blocking artifacts.
[0042] If both of the blocks j and k are motion predicted and do not include non-zero coefficients, generally referred to as residuals, then a determination at block 208 is made to check if the pixels on either side of the boundary are sufficiently different from one another. This may likewise be used to determine if the residuals are sufficiently small. If a sufficient difference exists then a blocking artifact is likely to exist. Initially a determination is made to determine if the two blocks use different reference frames, namely, R(j)≠R(k). If the blocks j and k are from two different reference frames then the boundary strength is assigned a value of one at block 210 . Alternatively, if the absolute difference of the motion vectors of the two image blocks is checked to determine if they are greater than or equal to 1 pixel in either vertical or horizontal directions, namely, |V(j,x)−V(k,x)|≧1 pixel or |V(j,y)−V(k,y)|≧1 pixel. Other threshold values may likewise be used, as desired, including less than or greater than depending on the test used. If the absolute difference of the motion vectors is greater than or equal to one then the boundary strength is assigned a value of one.
[0043] If the two blocks j and k are motion predicted, without residuals, are based upon the same frame, and have insignificant differences, then the boundary strength value is assigned a value of zero. If the boundary strength value is assigned a value of zero the boundary is not filtered or otherwise adaptively filtered accordingly to the value of the boundary strength. It is to be understood that the system may lightly filter if the boundary strength is zero, if desired.
[0044] The value of the boundary strength, namely, one, two, and three, is used to control the pixel value adaptation range in the loop filter. If desired, each different boundary strength may be the basis of a different filtering. For example, in some embodiments, three kinds of filters may be used wherein a first filter is used when Bs=1, a second filter is used when Bs=2 and a third filter is used when Bs=3. It is to be understood that non-filtering may be performed by minimal filtering in comparison to other filtering which results in a more significant difference. In the example shown in FIG. 8 the larger the value for Bs the greater the filtering. The filtering may be performed by any suitable technique, such as methods described in Joint Committee Draft (CD) of the Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG (JVT-C167) or other known methods for filtering image artifacts.
[0045] Skip mode filtering can be used with any system that encodes or decodes multiple image frames. For example, DVD players, video recorders, or any system that transmits image data over a communications channel, such as over television channels or over the Internet. It is to be understood that the system may use the quantization parameter as a coding parameter, either alone or in combination with other coding parameters. In addition, it is to be understood that the system may be free from using the quantization parameter alone or free from using the quantization parameter at all for purposes of filtering.
[0046] The skip mode filtering described above can be implemented with dedicated processor systems, micro controllers, programmable logic devices, or microprocessors that perform some or all of the operations. Some of the operations described above may be implemented in software and other operations may be implemented in hardware.
[0047] For the sake of convenience, the operations are described as various interconnected functional blocks or distinct software modules. This is not necessary, however, and there may be cases where these finctional blocks or modules are equivalently aggregated into a single logic device, program or operation with unclear boundaries. In any event, the functional blocks and software modules or described features can be implemented by themselves, or in combination with other operations in either hardware or software.
[0048] In some embodiments of the present invention as illustrated in FIG. 9, image data 902 may be input to an image data encoding apparatus 904 which includes the adaptive filtering portion as described above for some embodiments of the present invention. Output from the image data encoding apparatus 904 is an encoded image data and may then be stored on any computer-readable storage media 906 . The storage media may include, but is not limited to, disc media, memory card media, or digital tape media. Storage media 906 may act as a short-term storage device. The encoded image data may be read from storage media 906 and decoded by an image data decoding apparatus 908 which includes the adaptive filtering portion as described above for some embodiments of the present invention. The decoded image data may be provided for output decoded image data 910 to a display or other device.
[0049] In some embodiments of the present invention, as illustrated in FIG. 10, image data 1002 may be encoded and the encoded image data may then be stored on storage media 1006 . The basic procedure of image data encoding apparatus 1004 , storage media 1006 , and image data decoding apparatus 1008 is the same as in FIG. 9. In FIG. 10, Bs data encoding portion 1012 receives the value of the boundary strength Bs for each block boundary and encoded by any data encoding method which includes DPCM, multi-value run-length coding, transform coding with loss-less feature and so on. The boundary strength Bs may be generated as described in FIG. 8. The encoded boundary strength may then be stored on storage media 1006 . In one example, the encoded boundary strength may be stored separately from the encoded image data. In other example, the encoded boundary strength and the encoded image data may be multiplexed before storing on the storage media 1006 .
[0050] The encoded boundary strength may be read from the storage media 1006 and decoded by Bs data decoding portion 1014 to input the decoded boundary strength to image data decoding apparatus 1008 . When the decoded boundary strength is utilized in image data decoding apparatus 1008 to perform the adaptive filtering of the present invention, it may not be necessary to repeat the process described in FIG. 8 to generate boundary strength and this may save the processing power for the adaptive filtering.
[0051] In some embodiments of the present invention, as illustrated in FIG. 11, image data 1102 may be input to an image data encoding apparatus 1104 which includes the adaptive filtering portion as described above for some embodiments of the present invention. Output from the image data encoding apparatus 1104 is an encoded image data and may then be sent over a network, such as a LAN, WAN or the Internet 1106 . The encoded image data may be received and decoded by an image data decoding apparatus 1108 which also communicates with network 1106 . The image data decoding apparatus 1108 includes the adaptive filtering portion as described above for some embodiments of the present invention. The decoded image data may be provided for output decoded image data 1110 to a display or other device.
[0052] In some embodiments of the present invention, as illustrated in FIG. 12, image data 1202 may be encoded and the encoded image data may then be sent over a network, such as a LAN, WAN or the Internet 1206 . The basic procedure of image data encoding apparatus 1204 and image data decoding apparatus 1208 is the same as FIG. 11. In FIG. 12, Bs data encoding portion 1212 receives the value of the boundary strength Bs for each block and encoded by any date encoding method which includes DPCM, multi-value run-length coding, transform coding with loss-less features and so on. The boundary strength Bs may be generated as described in FIG. 8. The encoded boundary strength may then be sent over the network 1206 . In one example, the encoded boundary strength may be sent separately from the encoded image data. In other examples, the encoded boundary strength and the encoded image data may be multiplexed before sending over the network 1206 .
[0053] The encoded boundary strength may be received from the network 1206 and decoded by Bs data decoding portion 1214 to input the decoded boundary strength to image data decoding apparatus 1208 . When decoding boundary strength is utilized in image data decoding apparatus 1208 to perform the adaptive filtering of the present invention, it may not be necessary to repeat the process described in FIG. 8 to generate boundary strength and this may same the processing power for the adaptive filtering.
[0054] Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention may be modified in arrangement and detail without departing from such principles. Claim is made to all modifications and variation coming within the spirit and scope of the following claims. | Adjacent regions are identified in an image. Coding parameters for the adjacent regions are identified. Selective filtering is performed at the region between the identified adjacent regions. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a vertically movable foam sponge cutting apparatus, and more particularly to a foam sponge cutting apparatus in which the blade strip can be kept in a vertical state when moved left and right. In addition, the interval of the working section of the blade strip can be adjusted. The foam sponge or the like can be cut into products with various irregular or curved shapes. The cutting operation is facilitated and stabilized.
In a conventional foam sponge cutting apparatus, the interval of the working section of the blade strip is constant. Consequently, when cutting a hard foam sponge, the blade strip tends to deflect and cause unplane cutting face. This is because the interval of the working section of the blade strip is too large and thus the rigidity of the blade strip is insufficient. Therefore, the blade strip may be resiliently deformed to lead to unplane cutting face. Moreover, the cutting speed is slowed down. In addition, in cutting, when it is desired to change the position of the vertical blade strip, it is necessary to drive a control mechanism to shift the large and heavy structure body. This wastes a great amount of power. Also, the blade strip replacing device includes a rotary handle for adjusting a guide wheel. It is laborious to operate such rotary handle.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to provide a vertically movable foam sponge cutting apparatus in which the blade strip can be moved left and right in a vertical state and the working bench is able to move the work piece so that the foam sponge can be cut into products with various irregular or curved shapes. Therefore, the cutting operation can be speeded to save cost.
It is a further object of the present invention to provide the above foam sponge cutting apparatus in which by means of an ascending/descending device, the interval of the working section of the vertical blade strip can be changed. Therefore, the cutting operation will not be deflected and the cutting operation is stabilized and the planarity of cutting face is enhanced.
It is still a further object of the present invention to provide the above foam sponge cutting apparatus in which by means of the pulley unit, transmission mechanisms and guide rails, the movement of the blade strip can be accomplished by reversely synchronously sliding only a few elements. Therefore, it is no more necessary to ascend or descend the entire blade strip frame body and thus the power consumption is lowered.
It is still a further object of the present invention to provide the above foam sponge cutting apparatus on which a horizontal cutting device can be mounted at the same time.
According to the above objects, the blade turning unit movement control mechanism makes the upper and lower seat bodies of the blade turning unit are respectively synchronously moved along the linear slide bars and the guide rails of the linear slide bar seats. The two pulleys disposed on the upper and lower linear slide bars are also synchronously moved along therewith to keep the working section of the blade strip moving left and right in a vertical state. In addition, an ascending/descending device is used to change the interval of the working section of the blade strip. The blade strip deflection rectifying mechanism is able to automatically detect and rectify the deflection of the blade strip. The working bench is reciprocally linearly moved back and forth and the positions of the foam sponge and blade strip on the plane are adjusted by means of numeral control so as to cut the foam sponge into products with various irregular or curved shapes. A driving member serves to push the guide wheel to loosen the blade strip for easy replacement thereof. Therefore, the vertical cutting operation is facilitated and stabilized and the power consumption is reduced and thus the cost is lowered.
The present invention can be best understood through the following description and accompanying drawings wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a first embodiment of the foam sponge cutting apparatus of the present invention;
FIG. 2 is a front assembled view of the vertical blade strip structure of the present invention in which the cover of the blade strip frame is opened;
FIG. 3 is a side view of the working bench of the present invention;
FIG. 4 is an enlarged view of the blade strip deflection rectifying mechanism of the present invention;
FIG. 5 is a perspective view of the blade strip deflection rectifying mechanism of the present invention;
FIG. 6 is a front assembled view of a second embodiment of the vertical blade strip structure of the present invention in which the cover of the blade strip frame is opened;
FIG. 7 a shows the seat body of the second embodiment of the vertical cutting device of the present invention in a normal (not descended) state;
FIG. 7 b shows the seat body of the second embodiment of the vertical cutting device of the present invention in a descended state;
FIG. 8 is a front assembled view of the horizontal blade strip structure of the present invention, in which the cover of the blade strip frame is opened;
FIG. 9 is a front assembled view of the horizontal blade strip structure of the present invention, in which the cover of the blade strip frame is opened and the horizontal cutting device includes an extensible driving device;
FIG. 10 shows the application of the present invention in one state; and
FIG. 11 shows the application of the present invention in another state.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Please refer to FIGS. 1 to 3 . The present invention includes an apparatus body 10 and a blade strip frame 20 . A working bench 11 is mounted on the apparatus body 10 . A motor 13 is disposed under the working bench 11 and fitted with a toothed belt and wheel assembly 14 . Two ends of each of the front and rear sections of the working bench 11 are disposed with roller shafts 12 . The blade strip frame 20 is disposed with a vertical cutting device 16 (first embodiment). Each of the upper and lower beams of the vertical cutting device 16 is disposed with a linear slide bar 221 . A thread rod 31 is underlaid on lower side of the slide bar 221 . A guide rail 21 is disposed on upper side of slide bar 221 of the lower beam. The upper beam is disposed with a slide bar seat 22 the middle of which is a linear slide bar 221 . A thread rod 31 is underlaid on lower side of the slide bar 221 .
A blade turning unit 32 includes an upper and a lower blade seats. The upper blade seat is hung on the slide bar seat 22 and the lower blade seat is hung on the guide rail 21 . The upper and lower blade seats are respectively connected with the slide bars 221 .
Referring to FIGS. 2 and 4, a blade strip deflection rectifying mechanism 50 is disposed on the blade turning unit 32 . The blade holder 51 at front end is integrally connected with a first positive gear 52 for clamping a blade strip 90 . Two ends of the first positive gear 52 are respectively engaged with two positive gears 53 , 58 . A spiral rod 54 is engaged with upper side of the second positive gear 53 and a slide block 55 is disposed on the spiral rod 54 . A detector unit 56 is positioned beside the slide block 55 , including an upper detector A and a lower detector B. A third positive gear 58 is disposed at the output shaft of a servomotor 57 . As shown in FIGS. 4 and 5, when the blade face of the blade strip 90 is turned by a certain angle, the blade holder 51 is also turned by a certain angle to make the first positive gear 52 rotate and indirectly drive the adjacent second positive gear . 53 and the spiral rod 54 to rotate. Accordingly, the slide block 55 is vertically moved. When the turning angle of the blade strip 90 is responsive of the vertical moving height of the slide block and exceeds the allowed limit of the upper detector A or lower detector B, the detector unit 56 will detect this and immediately activate the servo motor 57 to operate forward or backward in time for driving the third positive gear 58 to rotate and drive the first positive gear 52 to rotate. Accordingly, the blade holder 51 can carry the blade strip 90 and rectify the deflection to a correct angle. Therefore, the detector unit is a safety device for automatically sensing and automatically rectifying the deflection.
Referring to FIG. 2, a guide wheel unit 40 includes a driving wheel 41 , two pulleys 43 , 47 and three guide wheels 44 , 45 , 46 . The driving wheel 41 is mounted on the lower beam of the blade strip frame 20 and connected with an output shaft of a motor. The lower blade seat pulley 43 is disposed under the lower blade seat of the blade turning unit 32 and positioned on the slide bar 221 and meshes with the thread rod 31 thereunder. The first and second guide wheels 44 , 45 are mounted at two ends of the upper beam. The upper edges of the two wheels are adjacent to the tangential position. The third guide wheel 46 has a smaller diameter and is disposed beside the second guide wheel 45 . The upper blade seat pulley 47 is disposed on the upper side of the slide bar 221 of the upper beam and meshes with the thread rod 31 thereunder. An oil cylinder 48 is horizontally disposed on outer side of the second guide wheel 45 and coupled therewith.
A blade strip 90 is wound over the driving wheel 41 and pulled upward to the first guide wheel 44 . Then the blade strip 90 is tangentially pulled to the second guide wheel 45 and further pulled to the third guide wheel 46 and then to the upper blade seat pulley 47 . The blade strip 90 vertically passes through the upper and lower blade seats and then is downward pulled to the lower blade seat pulley 43 . Finally, the blade strip is pulled back to the driving wheel 41 to form a circularly close winding space. The blade strip 90 includes a vertical working section X and other sections forming the circularly winding space.
The blade turning unit 32 is controlled by a movement control mechanism 93 . The output shaft end of a motor 23 via a toothed belt 25 and a toothed pulley 26 is coupled with a transmission shaft 24 . The upper and lower ends of the transmission shaft 24 are respectively vertically connected with the slide bars 221 and mesh with the thread rods 31 thereunder.
The ascending/descending device 15 includes a driving mechanism 92 on which the linear slide bar seat 22 is fitted. The driving mechanism 92 is driven by another motor 29 . The output shaft end of the other motor 29 via the toothed belt 25 and toothed pulley 26 is respectively coupled with a guide thread rod 30 . The guide thread rod 30 is screwed with a nut 222 of the slide bar seat 22 . The upper and lower ends of the guide thread rod are fitted with connecting rod bearing 28 . The top end is disposed with a toothed pulley 26 to respectively connect with two idle wheels 27 via the toothed belt 25 and further connect with the toothed pulley 26 at the top end of the guide thread rod 30 on the other side.
The present invention is characterized in that when the motor 23 outputs rotational power, the toothed belt 25 and the toothed pulley 26 are fitted with each other to drive the transmission shaft 24 to rotate. By means of the thread rods 31 under the respective linear slide bars 221 , the upper and lower seat bodies 33 of the blade turning unit 32 are respectively synchronously moved along the slide bar 221 and the guide rail 21 of the slide bar seats 22 . The upper blade seat pulley 47 and the lower blade seat pulley 43 are also guided by the thread rods 31 and synchronously reversely moved along therewith to keep the working section X of the blade strip 90 moving left and right in a vertical state. The motor 29 synchronously drives the guide thread rods 30 on two sides, whereby the slide bar seat 22 ascends/descends via the nuts 222 at two ends so as to change the interval of the working section X of the blade strip 90 .
When the motor drives the driving wheel 41 to rotate, the blade strip 90 is continuously revolved by means of the transmission of a guide wheel unit 40 so as to provide a cutting effect on the working bench 11 .
A pneumatic cylinder 48 pushes and displaces the second guide wheel 45 to change the circularly close winding space of the blade strip so as to loosen the blade strip 90 for replacement thereof.
FIGS. 6, 7 a and 7 b show another embodiment of the vertical cutting device 17 of the present invention. The vertical cutting device 17 includes a blade turning unit movement control mechanism 94 including two guide rails 121 and a thread rod 122 disposed on each of the upper and lower beams. The output shaft end of a motor 123 via a toothed belt 125 and a toothed pulley 126 is coupled with a transmission shaft 124 . The transmission shaft 124 is fitted with multiple connecting rod bearings 128 . The upper and lower ends of the transmission shaft 124 are respectively vertically connected with the thread rods 122 . The blade turning unit 32 includes an upper and a lower blade seats. The seat bodies 133 , 134 of the upper and lower blade seats are respectively hung on the upper and lower guide rails 121 and connected with the thread rods 122 . The blade strip 90 is wound on the guide wheel unit 40 to form a close winding line with a fixed length. The blade strip 90 includes a vertical working section X and other sections forming the circularly winding line, whereby the vertical cutting device 17 can be moved left and right with the blade strip kept vertical. The ascending/descending device 15 is such that a separable seat body 133 is hung on the guide rails 121 and the thread rod 122 disposed on the upper beam of the blade strip frame 20 . The seat body 133 includes an upper seat section 331 at upper end and a lower seat section 332 at lower end. The upper seat section 331 is fixed with a front end of a pneumatic cylinder 160 . The vertical lower seat section 332 is locked with an extensible stem 161 of rear end of the pneumatic cylinder 160 . Two connecting rods 162 are screwed and fixed on two sides of the lower seat section 332 and vertically fitted with the upper seat section 331 . An electric wire 170 is connected between the upper and lower seat sections, whereby the seat body 133 can ascend or descend to change the interval of the working section X of the blade strip.
In addition to the above vertical cutting device 16 , the other side of the blade strip frame 20 can be disposed with a horizontal cutting device 18 . The components of the horizontal cutting device are similar to those of the vertical cutting device 16 , while the guide wheel unit is installed in altered direction. Therefore, one single cutting apparatus can provide both vertical and horizontal cutting functions.
Referring to FIG. 8, the components of the guide wheel unit 40 ′ of the horizontal cutting device 18 are identical to those of the aforesaid guide wheel unit 40 . As shown in FIG. 2, the entire structure of the horizontal cutting device is alternatively arranged in a horizontal state, in which the blade strip 90 ′ is horizontally positioned on the apparatus body 10 . The blade turning unit 32 ′, the blade strip deflection rectifying mechanism 50 ′ and the blade turning unit movement control mechanism 93 ′ of the horizontal cutting device are also identical to those of the vertical cutting device.
Referring to FIG. 9, the components of the horizontal cutting device 18 can be identical to those of the aforesaid vertical cutting device 16 , including an extensible driving device 91 , while being arranged in altered direction to form a horizontal cutting device 19 in which the interval of the working section Y of the blade strip is changeable.
Referring to FIG. 10, in use for vertically cutting operation, the foam sponge 80 is placed on the working bench 11 and then the vertical cutting device 16 (or 17 ) is activated. The working bench is reciprocally linearly moved back and forth so as to cut the foam sponge along various irregular or curved cutting line 81 in vertical direction. The travel of the blade strip 90 depends on the change of the position of the wheels of the guide wheel unit 40 , whereby the driving power consumption is reduced so that the present invention can be easily and conveniently operated and is able to achieve a stable cutting effect. Therefore, the power consumption is reduced and the cost is lowered.
Referring to FIG. 11, in use for horizontally cutting operation, the foam sponge 80 is placed on the working bench 11 and then the horizontal cutting device 18 (or 19 ) is activated to similarly cut the foam sponge along various irregular or curved cutting line in horizontal direction. Therefore, both vertical and horizontal cutting can be performed on one single working bench. This reduces the room occupied by the equipment and indirectly lowers the cost.
However, since the vertical and horizontal cutting devices co-use the working bench, when using the vertical cutting device 16 (or 17 ), the horizontal cutting device 18 (or 19 ) should be shifted to the rear end of the travel to ensure safety.
According to the above arrangement, the present invention has the following advantages:
1. The ascending/descending device of the present invention serves to change the interval of the working section of the blade strip. When the interval is shortened, the cutting operation will not be deflected so that the cutting operation is stabilized and the planarity of cutting face is enhanced.
2. By means of the pulley unit, linear slide bars and guide rails, the shifting and changing of the interval of the blade strip can be accomplished only by sliding of a few elements so that the power consumption is reduced and the working cost is lowered.
3. The pneumatic cylinder serves to push the guide wheel to loosen the blade strip for easy replacement thereof.
4. The guide thread rod is fitted with connecting rod bearing so that the guide thread rod will not swing due to excessive length and the stability is enhanced.
5. One single apparatus includes both vertical and horizontal cutting devices so that the apparatus can be very conveniently used.
The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiments can be made without departing from the spirit of the present invention. | A vertically movable foam sponge cutting apparatus includes a vertical cutting device disposed on a blade strip frame. The vertical cutting device can be moved left and right in a vertical state. In addition, the vertical cutting device includes an ascending/descending device which is controllably movable up and down to change the rigidity of the blade strip in a cutting operation area. A foam sponge is cut along vertical cutting lines on a working bench. Therefore, a greater cutting function is achieved and the power consumption is lowered. | 8 |
FIELD OF THE INVENTION
This invention is a process for making a beta(2,6-disubstituted phenyl) amino acid. More specifically, this invention is a process for producing 2,6-disubstituted tyrosine.
SUMMARY OF RELATED ART
The preparation of a racemic mixture of 2,6-dimethyltyrosine is disclosed by H. I. Abrash and C. Niemann, Biochemistry, 2, 947 (1963). The method involves the protection of 3,5-dimethylphenol to form 3,5-dimethylphenyl ethyl carbonate which is then chloromethylated to form 3,5-dimethyl-4-chloromethylphenyl ethyl carbonate. The chloro is displaced with diethyl-2-acetamidomalonate at the 2-position to form the amido diester, which is subsequently acidolysed to form the racemic mixture of 2,6dimethyltyrosine.
The preparation of 2,6-dimethyl DL-phenylalanines is disclosed by R. R. Herr, T. Enkoji & J. P. Dailey, J. Amer. Chem. Soc., 79, 4229(1957). The method involves the conversion of 2,6-dimethyl aniline into its diazonium salt, followed by treatment with potassium cyanide and cuprous cyanide to produce 2,6-dimethylbenzonitrile. The benzonitrile is reduced with lithium aluminum hydride to provide 2,6-dimethylbenzylamine, which is reacted with excess methyl iodide producing 2,6dimethylbenzyltrimethylammonium iodide. The trimethylammonium group is displaced with diethyl-2acetamidomalonate to form the amido diester, which is subsequently acidolysed to form the racemic mixture of 2,6-dimethylphenylalanine.
These methods have the disadvantage that if one enantiomer is desired, the product mixture will have to be resolved. Applicant's process has overcome this disadvantage with a process that produces predominantly the natural (levorotatory) enantiomorph.
SUMMARY OF THE INVENTION
The present invention involves a process for the production of a beta(2,6-disubstituted) phenyl amino acid of the structure: ##STR1## wherein R is methylene or ethylene,
n is 0 or 1, R 2 and R 6 are independently alkyl, aryl, chloro, fluoro, alkoxy, carboalkoxy or nitro,
R 3 , R 4 and R 5 are independently hydrogen, alkyl, aryl, chloro, fluoro, alkoxy, carboalkoxy or nitro,
R 7 is an acid-protecting group and
R 8 is an amine-protecting group, comprising
(1) coupling a substituted phenyl compound of the structure ##STR2## wherein X is bromo, iodo, or diazonium and n is 0 or with an acylamino acrylate of the structure ##STR3## to form a substituted Z-3-(disubstituted phenyl) amino-protected acrylate of the structure, ##STR4##
(2) asymmetrically hydrogenating the acrylate obtained to form the desired 2,6-disubstituted phenyl amino acid, and optionally,
(3) deprotecting the protected 2,6-disubstituted phenyl amino acid.
M. Cutolo, et. al., Tet. Let., 24, 4603, (1983) disclose a coupling reaction involving the palladium catalyzed arylation of α-acetamidoacrylic acid. No examples of a 2,6-disubstitutedphenyl halide was disclosed.
Knowles et al, U.S. Pat. 4,261,919, Riley, U.S. Pat. 4,331,818 and Beck et al, U.S. Pat. 4,634,775 disclose the asymmetric hydrogenation of β-substituted-α-acylamidoacrylic acid. The preparation of 3-(3,4-dihydroxyphenyl)-L-alanine (L-DOPA) is disclosed in each of the above references. The above references, however, fail to disclose the hydrogenation of the 2,6-disubstituted phenylacylamino acrylate of the present invention.
None of the above references disclose the process of the present invention to produce a beta-(2,6-disubstituted phenyl) amino acid.
DETAILED DESCRIPTION OF THE INVENTION
The present invention involves a process to produce a beta-(2,6-disubstituted phenyl) amino acid by coupling a substituted phenyl compound with an acylamino acrylate to form a substituted acylamino acrylate, which is then hydrogenated to form a protected beta-(2,6-disubstituted phenyl) amino acid. Optionally, the protecting groups can be removed to form the 2,6-disubstituted phenyl amino acid.
The coupling reaction of the present invention involves the reaction of a disubstituted phenyl halide with an acylamino acrylate in the presence of a catalyst and is known in the art as the Heck reaction.
The Heck reaction is disclosed in U.S. Pat. 3,413,352, 3,574,777, 3,527,794, 3,700,727, 3,705,919, 3,763,213, 3,783,140, 3,922,299 and 3,988,358 which are hereby incorporated by reference. A catalyst suitable for the Heck reaction is a Group VIII metal, a preferred group being palladium, nickel and rhodium. A most preferred metal catalyst is palladium. Examples of suitable palladium catalysts include palladium diacetate, tetrakis(triphenylphosphine) palladium(O) and palladium dibenzylideneacetone. The preferred palladium catalyst is palladium diacetate. The catalyst concentration is not critical and can vary widely depending on reaction conditions. The concentration of the catalyst is in the range of 0.01 to 5.0 mole % based on the unsaturated organic halide. The preferred range is 1.0 to 2.0 mole % based on the unsaturated organic halide.
Optionally, a trivalent phosphorus or arsenic ligand can be used with the Group VIII metal catalyst. A trivalent phosphorus or arsenic ligand suitable for the present invention is the trialkyl, triaryl, trialkoxy, halo or triphenoxy derivative of phosphorus or arsenic or mixtures thereof. Examples of these ligands are triphenylphosphine, tri-n-butylphosphine, diphenylmethylphosphine, diphenylmethoxyphosphine, tri-methylphosphite, triethylphosphine, tri-ortho-tolylphosphine, phenyldi-n-butoxyphosphine, phosphorus trichloride, phenyldichlorophosphine, arsenic tribromide, triphenylarsine and triphenyl arsenite. The ratio of the ligand to the metal catalyst is not critical. The ratio can vary in the range of about 0.5:1 to about 10:1 mole ratio of ligand to metal catalyst.
The Heck reaction takes place in solution, in a slurry or neat. A preferred Heck reaction can be carried out using the unsaturated organic halide, a palladium catalyst, a phosphorus or arsenic ligand and a polar organic solvent that is inert to the reactants. Suitable polar organic solvents include N-methylpyrrolidone, acetonitrile, propionitrile, N-methyl formamide and dimethyl formamide (DMF). A preferred solvent is DMF.
The reaction temperature is any temperature sufficient to sustain the reaction and is in the range of about 50° C. to 175° C. A preferred reaction temperature range is from about 60° C. to about 110° C.
The Heck reaction can optionally take place in the presence of a base to absorb the acid generated in the reaction. Suitable bases are weak organic or inorganic bases that are inert to the reactants. Examples of such organic bases include trialkyl amines such as triethyl amine and tributyl amine and other inorganic bases such as sodium acetate, sodium bicarbonate and potassium bicarbonate. A preferred base is triethyl amine.
More specifically, the coupling step of the present invention is disclosed by M. Cutolo, et. al., Tet. Let., 24, 4603, (1983), which is hereby incorporated by reference. The α-acetamidocinnamic acids of the above reference are prepared by palladium catalyzed arylation of α-acetamidoacrylic acid using palladium acetate in the presence of triphenylphosphine or dichlorobis-(triphenylphosphine) palladium catalysts.
The substituted phenyl compound suitable for the coupling reaction is a substituted phenyl that minimally has a 2,6 substituent on the phenyl ring of the structure ##STR5## X is bromo, iodo or diazonium. Chloro and fluoro moieties typically do not couple in this reaction. A preferred X substituent is iodo, which gives unexpectedly high yields, in the range of 60 to 80 mole %. R 1 is a methylene or ethylene, such as methyl, or vinyl. R 2 and R 3 are independently alkyl, aryl, chloro, fluoro, alkoxy, carboalkoxy or nitro, or any substituent that will not couple with an acetamido acrylate in this reaction. Examples of suitable substituents for R 2 and R 6 are methyl, ethyl, n-propyl, iso-propyl, phenyl, benzyl, trifluoromethyl, chloro, methoxy, phenoxy, or chlorophenoxy. R 3 , R 4 and R 5 are independently hydrogen, alkyl, aryl, chloro, alkoxy or nitro. Suitable examples are given above. Examples of suitable substituted phenyl compounds include 2,6-dimethylphenyl bromide, 2,6-dimethylphenyl iodide, 4-hydroxy-2,6-dimethylphenyl iodide, 2,6-diethylphenyl bromide, 2,4,6-triphenyl phenyl iodide, 2,6dichlorophenyl iodide, 2,4,6-trimethylphenyl iodide, 4-methoxy-2-methyl-6-trifluoromethylphenyl 4-nitro-2,6-dipropylphenyl and 2,6-dimethoxyphenyl iodide.
The acylamino acrylate suitable for the present invention is of the structure ##STR6## where R 7 is an acid protecting group and R 8 is an amine protecting group. Suitable amine protecting groups include acetyl, benzoyl, formyl, carbobenzoxy (CBZ), 9-fluorenylmethyloxycarbonyl (Fmoc), 2-(4-biphenyl)propyl(2)oxycarbonyl (Bpoc), 2-phenylpropyl(2)oxycarbonyl (Poc) and t-butyloxycarbonyl (Boc). Suitable acid protecting groups include t-butyl, methyl, benzyl, beta-(trimethylsilyl)ethyl and trisubstituted silyl.
The asymmetric hydrogenation of β-substituted-α-acylamidoacrylic acid is disclosed by Knowles et al, U.S. Pat. 4,261,919, Riley, U.S. Pat. 4,331,818 and Beck et al, U.S. Pat. 4,634,775, which are hereby incorporated by reference. Any optically active coordinated metal hydrogenation catalyst known in the art to be suitable for asymmetric hydrogenation is appropriate for the process of the present invention. A suitable optically active hydrogenation catalyst used in this invention can be a coordination complex of a metal selected from the group consisting of rhodium, iridium, ruthenium, osmium, palladium and platinum, with a phosphine or arsine moiety of the formula AR 9 R 10 R 11 wherein A is phosphorus or arsenic and R 9 , R 10 and R 11 are each independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, phenyl and substituted phenyl. At least one of the moieties AR 9 R 10 R 11 must be optically active.
The hydrogenation catalyst is a complex of the formula ##STR7## where M is a transition metal selected from a group consisting of Rh, Ir, Ru and Os, Y is a chelating diene or two monodentate olefins, R 1 and R 2 are aryl or substituted aryl groups, R 3 and R 4 are alkyl, H or aryl substitutents, X is phosphorous or arsenic, A is an anion selected from the group consisting of PF 6 - , ClO 4 - , BF 4 - , CF 3 SO 3 - , Cl - , and Br - , and m is 1 or 2.
A preferred metal is rhodium. Examples of suitable rhodium catalyst complexes include [rhodium(1,5-cyclooctadiene)(R,R-1,2-ethanediylbis-(o-methoxyphenylphosphine] tetrafluoroborate ([Rh(COD)(R,R-DIPAMP)]BF 4 ), [rhodium (2,5-norbornadiene) (R-1,2-bis(diphenylphosphino)cyclohexylethane]hexafluorophosphate ([Rh(NBD)(R-Cycphos)]PF 6 ), [rhodium(2,5-norbornadiene)(2R,3R-bis(diphenylphosphine)butane]perchlorate ([Rh(NBD)(R,R-Chiraphos)]ClO 4 ), [rhodium(1,5-cyclooctadiene)(2R, 3R-O-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane] tetrafluoroborate ([Rh(COD)(R, R-Diop)BF 4 ), [rhodium (2,5-norbornadiene)(R-1, 2-bis(diphenylphosphine)propane) perchlorate ([Rh(R-Prophos]ClO 4 ), [rhodium(2,5-norbornadiene) (R-1,2-bis(diphenylphosphine)phenylethane)] perchlorate ([Rh(NBD)(R-Phenphos)]ClO 4 ) For the preparation of [Rh(R,R-Dipamp) COD]BF 4 , see Vineyard, B. D., Knolwes, W. S., Sabacky, M. J. Bachman, G. L. and Weinkauff, D. J., J. Amer. Chem. Soc., 1977, 99, 5046. For the preparation of [Rh(Diop)COD]BF 4 , see Kagan, H. B. and Dang, T. P., J. Amer. Chem. Soc., 1972, 94, 6429. For the preparation of [Rh(R-Cycphos) NBD]PF 6 , see Riley, D. P. and Shumate, R. E., J. Org. Chem., 1980, 45, 5187. The catalyst concentration is not critical and can vary widely depending on reaction conditions. The catalyst concentration is in the range of 0.0001 to 5 mole %, a preferred concentration being in the range of about 1 to 2 mole %.
The reaction temperature and pressure are not critical and can be a temperature and pressure sufficient to sustain the reaction. The temperature can be in the range of about 0° C. and 100° C. A preferred range is 25° C.-70° C . The hydrogen pressure can be in the range of about 5 to 1000 psi, (34 to 6890 kPa). A preferred range is from 5 to 100 psi (34 to 689 kPa).
The asymmetric hydrogenation yields a beta-(disubstituted phenyl) amino acid of predominantly one enantiomer. The predominant enantiomorph is present in the amino acid product in 80 mole % or greater excess. Typically, the process of the present invention will yield the desired enantiomorph in 90 mole % or greater excess with excesses of 99 mole % or more observed.
The protected phenyl amino acid can be deprotected by any suitable means. Typically deprotecting is effected by strong acid treatment. Suitable acids include hydrochloric acid and hydrobromic acid.
The following examples are for illustrative purposes only and are not intended to limit the scope of the invention in any manner.
In the examples given, if the opposite enantiomorph than is shown is desired (e.g., the S rather than the R, or vice versa), it is known in the art to select the asymmetric hydrogenation catalyst complex of the opposite optical activity to produce the desired enantiomorph.
EXAMPLE 1
N-butyloxycarbonyl-2,6-dimethyl-(S)-tyrosine was prepared by the following steps:
(a) 3,5-dimethyl-4-iodophenol was prepared as follows: To a solution of 59.1 g (484 mmol) of 3,5-dimethylphenol in 1 l of methanol was added 395 ml of 36% hydrochloric acid, with occasional cooling to maintain the temperature at 20°-30° C. To the resulting solution was then added a solution of 54.3 g (327 mmol) potassium iodide and 33.5 g (157 mmol) potassium iodate in 500 ml water over a 5 minute period. The solution became red and cloudy and a tan precipitate formed. After stirring at room temperature for 20 hours, the reaction mixture was cooled in ice and the precipitate collected and washed with ice cold 2/1 (v:v) water/methanol. The resulting tan solid was recrystallized several times from hot methanol and water to yield 36.4 g (15% yield) of white needles, mp 131°-132° C., which were identified as 3,5-dimethyl-4-iodophenol. 1 H NMR analysis indicated the following: (δ, CDCls) 8.03 (br s, lH), 6.52 (s, 2H) and 2.35 (s, 6H). Mass spectrum analysis indicated the following: (m/e) 248 (m+, 100%), 121, 91 and 77.
(b) O-Methyl-3,5-dimethyl-4-iodophenol was prepared by etherifying 3,5-dimethyl-4-iodophenol as follows: In a 1 l three-necked flask equipped with an overhead stirrer were placed 63.7 g (257 mmol) of 3,5-dimethyl-4-iodophenol, 70.9 g (513 mmol) potassium carbonate, 400 ml acetone and 47.5 ml (108 g, 760 mmol) methyl iodide. The reaction mixture was refluxed for 15 hours, cooled, the precipitate filtered and washed with acetone. The combined acetone washes were concentrated under reduced pressure, dissolved in methylene chloride, washed successively with 5% sodium hydroxide, saturated sodium bisulfite and water. After drying over magnesium sulfate and filtering, the solvent was removed under reduced pressure to afford a tan oil. Recrystallization from hot methanol with cooling to room temperature and then -78° C. afforded 58.2 g (86% yield) of white needles, mp 33°-34° C., which were identified as O-methyl-3,5-dimethy-4-iodophenol. 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.56 (s, 2H), 3.67 (s, 3H) and 2.37 (s, 6H). Mass spectrum analysis indicated: (m/e) 262 (m+, 100%), 247, 219, 135 and 91.
(c) Methyl-(Z)-α-acetamido-β-(2,6-dimethyl-4methoxyphenyl) acrylate was prepared by coupling O-methyl-3,5-dimethyl-4-iodophenol and methyl 2-acetamidoacrylate as follows: In a 500 ml three-necked flask equipped with an overhead stirrer (water cooled bearing), condenser and septum were placed 37.73 grams (144 mmol) O-methyl-3,5-dimethyl-4-iodophenol, 20.69 g (146 mmol) methyl 2-acetamidoacrylate, 2.17 g (7.13 mmol) tri-orthotolylphosphine and 0.61 g (2.71 mmol) palladium(II) acetate. After flushing well with argon for 15 minutes and mixing well, 43 ml (31.22 g, 309 mmol) of triethylamine, previously degassed by purging with nitrogen for 15 minutes, was added. The reaction was warmed to 100° C. over a thirty minute period in an oil bath and then held at that temperature with stirring for 14 h. After cooling to room temperature, 500 ml of methylene chloride was added and the resulting slurry was passed through 100 g of silica gel, followed by washing with 1 l of ethyl acetate. The resulting solution was then evaporated to dryness, dissolved in methylene chloride and successively washed with 10% hydrochloric acid, saturated sodium bicarbonate and saturated sodium chloride. After drying over magnesium sulfate and filtering, the solvent was removed under reduced pressure to afford 39 g of a tan solid. Recrystallization from hot ethyl acetate and hexane yielded 24.14 g (60% yield) of white needles, mp 143°-143.5° C., which were identified as Methyl-(Z)-α-acetamido-β-(2,6-dimethyl-4-methoxyphenyl) acrylate. 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.12 (br s, 1H), 6.65 (s, 2H), 6.59 (br s, lH), 3.90 (s, 3H), 3.81 (s, 3H), 2.22 (s, 6H) and 1.99 (br s, 3H). Mass spectrum analysis indicated: (m/e) 277 (m+, 100%), 246, 235, 218, 176, 174 and 160.
(d) N-Acetyl-2,6 dimethyl-O-methyl-(S)-tyrosine methyl ester was prepared by hydrogenating methyl-(Z)-a-acetamido-β-(2,6-dimethyl-4-methoxyphenyl) acrylate as follows: In a 500 ml Fisher-Porter bottle was placed 24.18 g (87 mmol) of methyl (Z)-α-acetamido-β-(2,6-dimethyl-4-methoxyphenyl) acrylate and 1.50 g (2.0 mmol) [Rh(COD)R,R-DIPAMP)]BF 4 . The system was taken into the dry box, sealed and removed. Through a septum was added 250 ml of methanol which had previously been purged for 1 hour with nitrogen. The system was flushed five times with 30 psig of hydrogen, charged to 30 psig hydrogen and immersed in an oil bath at 50° C. The reaction was maintained at 50° C. under 30 psig hydrogen for 16 hours. After venting and cooling, the methanol solution was concentrated at 60° C. to approximately 100 ml whereupon crystallization began to occur. After cooling to room temperature and then to 0° C., the crystals were collected and washed with cold methanol, then air dried to yield 21.42 g (88% yield) of white crystals, mp 152°-153° C., which were identified as N-Acetyl-2,6-dimethyl-O-methyl-(S)-tyrosine methyl ester. 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.59 (s, 2H), 6.14 (br d, J=8 Hz, 1H, NH), 4.78 (q, J=7.5 Hz, 1H), 3.78 (s, 3H), 3.64 (s, 3H), 3.06 (d, J=7.5 Hz, 2H), 2.33 (s, 6H) and 1.98 (s, 3H). Mass spectrum analysis indicated: (m/e) 280 (M+H), 248, 238, 220 and 149. Analysis by chiral gas chromatography using a Chirasil-Val III fused silica column showed a 99.6/0.4 mixture of S and R isomers, respectively. The mother liquors were concentrated, passed through silica gel with ethyl acetate and concentrated to yield 2.70 g of a mixture, which was shown to contain starting olefin, S-isomer and R-isomer in a 24/65/11 ratio, respectively.
(e) 2,6-Dimethyl-(S)-tyrosine hydrobromide was prepared by deprotecting N-acetyl-2,6-dimethyl-O-methyl-(S)-tyrosine methyl ester as follows: In a 100 ml round-bottom flask were placed 18.56 g (66 mmol) of N-acetyl-2,6dimethyl-O-methyl-(S)-tyrosine methyl ester, 0.63 g (3.3 mmol) sodium metabisulfite, 43 ml 48% hydrobromide acid and 21 ml acetic acid. After flushing with nitrogen, the flask was immersed in an oil bath at 120° C. and maintained there for 15 hours. After cooling, the volatiles were removed under reduced pressure at 100° C. to afford a tan solid of the desired product, contaminated with sodium metabisulfite. A sample was derivatized with Marfey's reagent and shown by HPLC analysis to be a 99.7/0.3 mixture of S and R isomers, respectively. 1 H NMR analysis indicated: (δ, CD 3 OD) 6.55 (s, 2H), 4.07 (br t, J=7.5 Hz, 1H), 3.32 (dd, J=7.5 and 14.1 Hz, 1H), 3.15 (dd, J= 7.5 and 14.1 Hz, 1H) and 2.31 (s, 6H). Mass spectrum analysis indicated: 209 (M+), 135 (100%) and 91.
(f) The amine of 2,6-dimethyl-(S)-tyrosine hydrobromide was protected to form N-t-butyloxy-carbonyl-2,6-dimethyl-(S)-tyrosine as follows: The crude 2,6-dimethyl-(S)-tyrosine hydrobromide salt from step (e) above (approx. 66 mmol) was dissolved in 110 ml of water and 110 ml of dioxane were added. The pH was adjusted to 9 with the addition of 10% aqueous sodium hydroxide. After cooling to 20° C., 20 ml (19 g, 87 mmol) of di-t-butylpyrocarbonate was added. The reaction was maintained at a pH of between 8.5 and 8.8 by the addition of 10% sodium hydroxide and kept between 20° C. and 30° C. by occasional cooling in ice. After 1.5 hours, the pH was no longer changing and analysis by thin layer chromatography indicated the absence of free amino acid. The dioxane was removed under reduced pressure, cold 0.2N hydrochloric acid added and the resulting solids extracted into ethyl acetate. The ethyl acetate layer was separated, washed with water and saturated sodium chloride solution, dried with magnesium sulfate, filtered and removed under reduced pressure to afford a white foam, 21.21 g. This was dissolved in hot ethyl acetate and hexane added to crystallize the product. This was collected, washed with hexane and air dried to afford 16.85 g (83% yield) of a white powder, mp 165°-170° C. with decomposition, which was identified as N-t-butyloxycarbonyl-2,6-dimethyl-(S)-tyrosine. 1 H NMR analysis indicated: (δ, d 6 -acetone) 6.50 (s, 2H), 5.29 (br d, J=7 Hz, 1H, NH), 4.42-4.28 (m, 1H), 3.08 (dd, J=6.2 and 14.3 Hz, 1H), 2.92 (dd, J=8.5 and 14.3 Hz, 1H), 2.29 (s, 6H) and 1.37 (s, 9H). Mass spectrum analysis indicated: (m/e) 310 (M+H), 254 (100%), 210 and 164, and [α] D 25 =-13.4 (c=7.6 mg/mL, ETOH). A small sample was deprotected with 45% trifluoroacetic acid/5% anisole/50% methylene chloride, stripped, derivatized with Marfey's reagent (1-fluoro-2,4-dinitro-5-L-alanine amide) and analyzed by HPLC, which showed a 99.7/0.3 mixture of S and R isomers, respectively.
EXAMPLE 2
N-Butyloxycarbonyl-2,6-dimethyl-(5)-tyrosine was prepared by the following steps:
(a) 0-Benzyl-3,5-dimethyl-4-iodophenol was prepared as follows: In a 500 ml round-bottom flask were placed 30.0 g (121 mmol) of 3,5-dimethyl-4-iodophenol, 190 ml acetone, 16.9 g (122 mmol) potassium carbonate and 20.7 g (121 mmol) benzyl bromide. The mixture was refluxed for 15 hours, cooled, filtered and the precipitate washed with acetone. The combined filtrate was evaporated under reduced pressure to yield an orange oil which slowly crystallized. This was dissolved in methylene chloride and water and the methylene chloride layer sequentially washed with 5% sodium hydroxide, saturated sodium bisulfite and water. After drying over magnesium sulfate and filtering, the methylene chloride was removed under reduced pressure. The resulting solid was recrystallized from hot methanol, cooled to room temperature and then in ice, collected and washed with cold methanol to yield 27.9 g (68% yield) of white plates, mp 56-57, which were identified as O-Benzy13,5-dimethyl-4-iodophenol. 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.68 (m, 5H), 6.62 (s, 2H), 4.88 (s, 2H) and 2.39 (s, 6H). Mass spectrum analysis indicated: (m/e) 338 (M+) and 91.
(b) Methyl (Z)-α-acetamide-β-(2,6-dimethyl-4-benzyloxyphenyl)acrylate was prepared by coupling 0-benzyl-3,5-dimethyl-4-iodophenol with methyl 2-acetamide-acrylate as follows: In a 100 ml round-bottom flask was placed 9.99 g (29.5 mmol) O-benzyl-3,5dimethyl-4-iodophenol, 4.46 g (31.4 mmol) methyl 2-acetamidoacrylate, 0.49 g (1.6 mmol) tri-ortho-tolyphosphine and 141 mg (0.63 mmol) palladium(II) acetate. The flask was evacuated and argon added. This was repeated five times. To the reaction was then added 8.5 ml (6.2 g, 61 mmol) of triethylamine (previously degassed by purging with nitrogen for 15 minutes). The mixture was then warmed to 100° C. over 15 minutes and maintained there for 15 hours. After cooling to room temperature, ethyl acetate was added and the slurry filtered through silica gel, which was then eluted with ethyl acetate. The combined ethyl acetate washes were extracted with 10% hydrochloric acid and saturated sodium chloride, dried over magnesium sulfate, filtered and concentrated under reduced pressure to afford a tan solid. This was recrystallized from hot ethyl acetate and hexane to yield 7.28 g (70% yield) of whit needles, mp 138-139, which were identified as methyl (Z)-α-acetamido-β-(2,6-dimethyl-4-benzloxyphenyl) acrylate. 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.18 (m, 5H), 6.99 (s, 1H), 6.63 (br s, 1H), 6.58 (s, 2H), 4.90 (s, 2H), 3.74 (s, 3H), 2.12 (s, 6H) and 1.86 (s, 3H). Mass spectrum analysis indicated: (m/e) 353 (M+), 262, 220 and 91 (100%).
(c) N-Acetyl-2,6-dimethyl-(S)-tyrosine methyl ester was prepared by hydrogenating methyl-(Z)-α-acetamide β-(2,6-dimethyl-4benzyloxyphenyl) acrylate as follows: In a 500 ml Fisher Porter bottle were placed 6.55 g (18.5 mmol) of methyl (Z)α-acetamido-β-(2,6-dimethyl-4-benzyloxyphenyl) acrylate and 141 mg (0.19 mmol) of [Rh(COD)R,R-DIPAMP)]BF 4 .
The bottle was taken into the dry box and sealed. After removal from the dry box, 90 ml of methanol (previously purged with nitrogen for one hour) was added. The system was flushed five times with 40 psig nitrogen, then three times with 30 psig hydrogen and then pressurized to 30 psig hydrogen. The reactor was then warmed to 50° C. and maintained under 30 psig hydrogen for twenty-four hours. After cooling to room temperature and venting, the reaction solution was filtered and the filtrate was concentrated under reduced pressure. The resulting material was chromatographed on a Waters Prep 500 Chromatagram using 50% ethyl acetate/hexane (v:v) to afford 6.5 g of a white solid; 1 H NMR spectrum indicated approximately 20% debenzylation. This material was then dissolved in 90 ml of degassed methanol, 2.0 g of 5% palladium on carbon added under nitrogen and then hydrogenated under 30 psig (207 kPa) hydrogen at room temperature for twenty hours. After venting and flushing with nitrogen, the reaction was filtered and the filtrate concentrated under reduced pressure to afford 4.24 g of a white solid. This was crystallized from hot chloroform and hexane to yield 3.40 g (69%) of white crystals, mp 156-157° C., identified as N-acetyl-2,6-dimethyl-(S)-tyrosine methyl ester. 1 H NMR analysis indicated: (δ, CDCl 3 ) 8.55 (br s, 1H), 7.80 br d, J=7 Hz, 1H, NH), 6.38 (s, 2H), 4.52 (q, J=7 Hz, 1H), 3.53 (s, 3H), 3.10-2.80 (m, 2H), 223 (s, 6H) and 1.92 (s, 3H). Mass spectrum analysis indicated: (m/e) 265 (M+), 206 and 135 (100%).
(d) 2,6-Dimethyl-(S)-Tyrosine hydrochloride was prepared by deprotecting N-acetyl-2,6-dimethy-(S)-tyrosine methyl ester as follows: In a 100 ml round-bottom flask was placed 3.40 g (13 mmol) of N-acetyl-2,6-dimethyl-(S)-tyrosine methyl ester and 20 mL of 6N hydrochloric acid. The reaction mixture was refluxed under argon for 41/2 hours, cooled and then concentrated under reduced pressure to afford 3.48 g of a white solid; 1 H NMR analysis indicated: (δ, CD 3 OD) 6.35 (s, 2H), 3.90 (t, J=7 Hz, 1H), 3.3-3.0 (m, 2H) and 2.21 (s, 6H). Mass spectrum analysis indicated: (m/e) 209 (M+), 135 (100%) and 91.
(e) The amine of 2,6-dimethyl-(S)-tyrosine hydrochloride was deprotected to form N-t-Butyloxy-carbonyl-2,6-dimethyl-(S)-tyrosine as follows: The crude 2,6-dimethyl-(S)-tyrosine hydrochloride from the step above (approx. 13 mmol) was dissolved in 20 ml of water and then 20 ml of dioxane was added. The pH of the solution was adjusted to 8.5 by the addition of 5% aqueous sodium hydroxide solution. The temperature of the reaction was maintained between 20° and 30° C. by occasional cooling in ice, and 3.1 ml (2.95 g, 13.5 mmol) of di-t-butylpyrocarbonate was added all at once. The pH was maintained between 8.5 and 8.8 by the addition of 5% sodium hydroxide solution. After approximately two hours, the pH of the solution had stopped changing and analysis by thin layer chromatography indicated the absence of free amino acid. The dioxane was removed under reduced pressure, cold 0.2N hydrochloric acid added and the resulting solids extracted into ethyl acetate. The ethyl acetate layer was separated, washed with water and saturated sodium chloride solution, dried with magnesium sulfate, filtered and removed under reduced pressure to afford 4.08 g of a white solid. This was dissolved in hot ethyl acetate and hexane added to crystallize the product, which was collected, washed with hexane and air dried to yield 3.34 g (83% yield) of a white solid, mp 173°-176° with decomposition. This was identified as N-t-butyloxycarbonyl-2,6-dimethyl-(S)-tyrosine. 1 H NMR and mass spectrum were identical to the previously prepared material. An HPLC analysis of this material after deprotecting and derivatization with Marfey's reagent showed a 98:2 mixture of S and R enantiomers, respectively.
EXAMPLE 3
The asymmetric hydrogenation of methyl (Z)-α-acetamido-β-(2,6-dimethyl-4-methoxyphenyl)acrylate was effected with the following various chiral rhodium catalysts. Methyl (Z)-α-acetamido-β-(2,6-dimethyl-4-methoxyphenyl)acrylate was hydrogenated to N-acetyl-2,6-dimethyl-O-methyl-(S)-tyrosine methyl ester following the procedure shown above, but using several chiral rhodium catalyst. The S:R enantiomer ratios using the different catalysts were as follows; [Rh(COD)(R,R-DIPAMP)]BF 4 (96:4), [Rh(COD)(R,R-Diop)]BF 4 (83:17) and [Rh(NBD)(R-Cycphos)]PF 6 (93:7).
EXAMPLE 4
N-t-Butyloxycarbonyl-6-methyl-2-(a,a,a-trifluoromethyl)-(S)-tyrosine was prepared in the following steps:
(a) 4-Methoxy-2-(α,α,α-trifluoromethyl)nitrobenzene was prepared as follows: In a 2 1 three-necked flask equipped with an overhead stirrer and condenser, was placed 75.4 g (0.334 moles) of 5-chloro-2-nitrobenzotrifluoride. After placing the reaction flask under a nitrogen atmosphere, 1 l (0.50 mole) of a 0.5M solution of sodium methoxide in methanol was added all at once. This was then refluxed for sixteen hours, cooled and the volatiles removed under reduced pressure. Cold water was added, followed by methylene chloride. The layers were separated and the organic layer successively washed with water and saturated sodium chloride solution. After drying over magnesium sulfate and filtering, the solvent was removed under reduced pressure to afford 68.7 g of a yellow solid. This was recrystallized from methanol and water to yield 54.9 g (75% yield) of light yellow crystals, which were identified as 4-methoxy-2-(α,α,α-trifluoromethyl)nitrobenzene; 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.91 (d, J=9 Hz, 1H), 7.18 (dd, J=2 and 9 Hz, 1H), 7.02 (d, J=2 Hz, 1H) and 3.92 (s, 3H).
(b) 4-Methoxy-2-(α,α,α-trifluoromethyl)aniline
prepared by aminating 4-methoxy-2-(α,α,α-trifluoromethyl)nitrobenzene as follows: In a 300 ml stainless steel autoclave was placed a solution of 25.0 g (0.11 mole) of 4-methoxy-2-(α,α, α-trifluoromethyl)nitrobenzene in 150 ml of 95% ethanol. After flushing with nitrogen, 1.1 g of 5% palladium on carbon was added and the autoclave sealed. After flushing with nitrogen, the reactor was charged with 60 psi (413 kPa) of hydrogen and stirred. Gas uptake began immediately and the temperature was maintained between 25° C. and 30° C. by occasional cooling with an ice bath. After approximately ninety minutes, the gas uptake had ceased. The autoclave was vented, flushed with nitrogen and opened. The catalyst was filtered off and the filtrate was concentrated under reduced pressure to afford 22 g (100% yield) of a light yellow oil which was shown to be 4-methoxy-2-(α,α,α-trifluoromethyl)aniline. 1 H NMR analysis indicated: (δ, CDClz) 7.82 (dd, J= 2 and 9 Hz, 1H), 7.00 (d, J=2 Hz, 1H), 6.48 (d, J=9 Hz, 1H), 3.87 (br s, 2H) and 3.60 (s, 3H). Mass spectrum analysis indicated: (m/e) 191 (M+), 176, 156, 128 and 52. It was used directly in the next step without purification.
(c) 4-Methoxy-6-(methylthiomethyl)-2-(α,α,α-trifluoromethyl)aniline was prepared by substituting 4-methoxy-2-(α,α,α-trifluoromethyl)aniline as follows: In a 250 ml three-necked flask equipped with an overhead stirrer was placed 20.12 g (0.105 mol) of 4-methoxy-2-(α,α,α-trifluoromethyl)aniline in 100 ml of methylene chloride. To the solution was then added 15.63 g (0.117 mol) of N-chlorosuccinimide was added with vigorous stirring. After cooling to 0° C. under a nitrogen atmosphere, a solution of 9.2 ml (8.02 g, 0.129 mol) dimethylsulfide in 40 ml of methylene chloride was then added over a one hour period while maintaining the temperature below 5° C. The reaction mixture became very thick. The ice bath was removed and after stirring at room temperature for one hour, 200 ml of ice cold 5% aqueous sodium hydroxide solution was added. The methylene chloride layer was separated, dried over anhydrous potassium carbonate, filtered and the solvent removed under reduced pressure. To the residue was then added 60 ml of 1,2-dichloroethane and 1.00 g (10 mmol) of succinimide. After refluxing for twelve hours under a nitrogen atmosphere, the reaction mixture was cooled, washed twice with 100 ml of 5% sodium hydroxide solution, dried with magnesium sulfate, filtered and concentrated under reduced pressure to afford 24.9 g of a black oil. This was distilled under reduced pressure to afford 16.5 g (63% yield) of the desired product as a clear, colorless liquid (Bp 106°-110° at 0.35 mm Hg) of 95% purity as assayed by gas chromatography; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.94 (d, J=1.8 Hz, 1H), 6.78 (d, J=1.8 Hz, 1H), 4.32 (br s, 2H, NHz), 3.54 (s, 3H), 3.51 (s, 2H) and 1.82 (s, 3H). Mass spectrum analysis indicated: (m/e) 251 (M+), 204 (100%) and 181.
(d) 4-Methoxy-6-methyl-2-(α,α,α-trifluoro-methyl)aniline was prepared by deprotecting 4-methoxy-6-(methylthiomethyl)-2-(α,α,α-trifluoromethyl)aniline as follows: In a 300 ml Hastelloy C autoclave were placed 16.4 g (0.065 mol) of 4-methoxy-6-(methylthiomethyl)2-α,α,α-trifluoromethyl)aniline, 8.0 g of a Co:Mo(S) catalyst (Co:Mo=1:1) (see S. J. Tremont and P. L. Mills, J. of Catalyl., 1986, 97, 252) and 100 ml of toluene. The system was flushed three times with 500 psi (3445 kPa) of nitrogen and then three times with 500 psi (3445 kPa) of hydrogen. The autoclave was charged with 1000 psi (6890 kPa) of hydrogen, heated to 200° C. and then the hydrogen pressure increased to 2000 psi (13780 kPa). After four days at 200° C. and 2000 psi hydrogen, the autoclave was cooled, vented, flushed with nitrogen and emptied. The catalyst was removed by filtering and the toluene removed under reduced pressure at 50° C. to yield 12.5 g of an oil, which was distilled to afford 9.4 g (70% yield) of a clear colorless oil (Bp 50-54 at 0.15 mm Hg) which was identified as 4-methoxy-6-methyl-2-(α,α,α-trifluoromethyl)aniline 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.71 (m, 2H), 3.72 (br s, 2H, NH), 3.56 (s, 3H) and 2.06 (s, 3H). Mass spectrum analysis indicated: (m/e) 205 (M ), 190, 170 and 142.
(e) 4-Methoxy-6-methyl-2-(α,α,α-trifluoromethyl)iodo-benzene was prepared by coupling 4-methoxy-6-methyl-2-(α,α,α-trifluoromethyl)aniline as follows: In a 250 ml three-necked flask equipped with an overhead stirrer was placed 25 ml of concentrated hydrochloric acid. After cooling to -20° C., 9.3 g (45 mmol) of 4-methoxy-6-methyl-2-(α,α,α-trifluoromethyl)aniline was added over a five minute period. A thick white precipitate of the hydrochloride salt was formed. To the resulting slurry was slowly added over fifteen minutes a solution of 3.81 g (55 mmol) of sodium nitrite in 15 ml of water. The cooling bath was replaced with an ice bath and after stirring for ten minutes, a solution of 40 g (240 mmol) of potassium iodide in 100 ml of water was added over fifteen minutes. The ice bath was removed and the reaction stirred at room temperature for fifteen hours. Methylene chloride was added, the layers separated and then the organic layer washed with 10% sodium hydroxide, saturated sodium bisulfite and water, dried with magnesium sulfate, filtered and concentrated under reduced pressure to afford 13.4 g of a brown oil which solidified. This was dissolved in 150 ml of methanol, filtered, water added to the cloud point and slowly allowed to crystallize. In this manner, 10.0 g (70% yield) of slightly tan crystals were obtained, mp 38°-39° C., and identified as 4-methoxy-6-methyl2-(α,α,α-trifluoromethyl)iodobenzene; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.93 (d, J=1.8 Hz, 1H), 6.85 (d, J=1.8 Hz, 1H), 3.71 (s, 3H) and 2.46 (s, 3H). Mass spectrum analysis indicated: (m/e) 316 (M+).
(f) Methyl (Z)-α-acetamido-β-[4-methoxy-6-methyl-2(α,α,α-trifluoromethyl)phenyl]acrylate was prepared by coupling 4-methoxy-6-methyl-2-(α,α,α-trifluoromethyl) 2-acetamido-acrylate as follows: In a 100 ml round-bottom flask equipped with a stir bar were placed 9.72 g (30.7 mmol) of 4-methoxy-6-methyl-2-(α,α,α-trifluoromethyl)iodobenzene, 4.80 g (33.8 mmol) of methyl 2-acetamidoacrylate, 468 mg (1.54 mmol) tri-ortho-tolyphosphine and 138 mg (0.62 mmol) of palladium (II) acetate. After swirling to mix well, the flask was evacuated and then argon added. This was repeated five times. Under an argon flow, 9 ml (6.5 g, 65 mmol) of triethylamine (previously purged with nitrogen for ten minutes) was added, the reaction warmed to 100° C. over thirty minutes and then maintained there for twenty hours. After cooling to room temperature, methylene chloride was added and the slurry passed thru silica gel, which was then washed with ethyl acetate. The combined filtrates were concentrated under reduced pressure, redissolved in methylene chloride and washed with 10% hydrochloric acid, dried over magnesium sulfate, filtered and concentrated under reduced pressure to afford 9.44 g of residue, which was shown by gas chromatography to be a 40:60 mixture of starting iodide and the desired product, respectively. This was chromatographed using a Waters Prep 500A Chromatogram using silica gel and eluting with 25% ethyl acetate/hexane (v:v) to yield 2.90 g of product. This was recrystallized from hot ethyl acetate and hexane to give 2.09 g (21% yield) of white needles which were identified as methyl (Z)-α-acetamido-β-[4-methoxy-6-methyl-2-(α,α,.alpha.-trifluoromethyl) phenylacrylate, mp 154°-155° C.; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.95 (br s, 1H), 6.78 (d, J=1.8 Hz, 1H), 6.64 (d, J=1.8 Hz, 1H), 6.37 (br s, 1H), 3.63 (s, 3H), 3.60 (s, 3H), 2.02 (s, 3H) and 1.72 (s, 3H). Mass spectrum analysis indicated:(m/e) 331 (M ), 289, 230 (100%) and 43.
(g) N-Acetyl-6-methyl-2-(α,α,α-trifluoromethyl)-O-methyl-(S)-tyrosine methyl ester was prepared by hydrogenating (Z)-α-acetimido-β-[4-methoxy-6-methyl-2-(α,α,.alpha.-trifluoromethyl)-phenyl]acrylate as follows: In a 250 ml Fisher-Porter bottle were placed 2.00 g (6.0 mmol) of methyl (Z)α-acetamido-β-[4-methoxy-6-methyl-2-(α,α,α-trifluoromethyl)phenyl]acrylate and 238 mg (0.31 mmol) of [Rh(COD)(R,R-DIPAMP)]BF 4 . The bottle was taken into the dry box and sealed. After removal from the dry box, 20 ml of methanol (previously purged with nitrogen for one hour) was added. The system was flushed five times with 40 psig (276 kPa) of nitrogen, then three times with 30 psig (207 kPa) of hydrogen and then pressurized with 30 psig (207 kPa) of hydrogen. The reactor was then warmed to 50° C. and maintained under 30 psig of hydrogen for twenty-four hours. After cooling to room temperature and venting, the solution was concentrated under reduced pressure to afford a residue. This was chromatographed on a 4 mm silica gel plate using a chromatatron to afford 1.93 g (96% yield) of a white solid which was identified as N-acetyl-6-methyl-2-(α,α,α-trifluoromethyl)-O-methyl-(S)-tyrosine methyl ester, mp 158°-158.5° C.; 1 H NMR analysis indicated: (δ, CDCL 3 /d 6 -DMSO) 6.81 (d, J=8 Hz, 1H, NH), 6.69 (d, J=1.8 Hz, 1H), 6.62 (d, J=1.8 Hz, 1H), 4.54 (q, J=7 Hz, 1H), 3.50 (s, 3H), 3.31 (s, 3H), 2.86 (AB of ABX, 2H), 2.18 (s, 3H) and 1.64 (s, 3H). Mass spectrum analysis indicated: (m/e) 333 (M ), 274 and 203 (100%). Analysis of this material by chiral gas chromatography showed a 97.6/2.4 mixture of S and R isomers, respectively.
(h) 6-Methyl-2-(α,α,α-trifluoromethyl)-(S)-tyrosine hydrobromide was prepared by deprotecting
N-acetyl-6-methyl-2-(α,α,α-trifluoromethyl)-O-methyl-(S)-tyrosine methyl ester as follows: In a 25 ml round-bottom flask were placed 1.83 g (5.5 mmol) of N-acetyl-6-methyl-2-(α,α,α-trifluoromethyl)-O-methyl-(S)-tyrosine methyl ester, 51 mg (0.27 mmol) of sodium metabisulfite, 4 ml of 48% hydrobromic acid and 2 ml of acetic acid. After flushing with nitrogen, the mixture was placed i an oil bath at 120° C. for twenty hours, cooled and concentrated under reduced pressure to afford a brown solid which was shown to be 6-methyl-2-(α,α,α-trifluoromethyl)-(S)-tyrosine hydrobromide, contaminated with sodium metabisulfite. 1 H NMR analysis indicated: (δ, CD 3 OD) 6.85 (m, 2H), 4.06 (t, J=7 Hz, 1H), 3.28 (d, J=7 Hz, 2H) and 2.36 (s, 3H). Mass spectrum analysis indicated: (m/e) 264 (M+1), 189, 81 and 74. A sample was derivatized with Marfey's reagent and analyzed by high pressure liquid chromatography and shown to be a 96.4/3.6 ratio of S and R isomers, respectively.
(i) The amine of 6-methyl-2-(α,α,α-trifluoromethyl)-(S)-tyrosine hydrobromide was protected to form N-t-butyloxycarbonyl-6-methyl-2-(α,α,α-trifluoromethyl)-(S)-tyrosine as follows: The crude 6-methyl-2-(α,α,α-trifluoromethyl)-(S)tyrosine hydrobromide salt from above (approx. 5.5 mmol) was dissolved in 8 ml of water and 8 ml of dioxane was added. After bringing the pH to 8.8 by the addition of 5% sodium hydroxide solution, the mixture was cooled to 15° C., 1.4 ml (1.45 g) of di-t-butylpyrocarbonate was added and the ice bath removed. The pH was maintained between 8.5 and 8.8 by the addition of 5% sodium hydroxide solution. After two hours, the pH had stabilized and analysis by thin layer chromatography indicated the absence of the free amino acids. The dioxane was removed under reduced pressure, ice cold 0.2N hydrochloric acid added and the precipitate extracted into ethyl acetate. After washing with water and saturated sodium chloride solution, drying with magnesium sulfate and filtering, the solvent was removed under reduced pressure to afford 1.73 g of a white foam. This was recrystallized from methylene chloride/hexane to yield 1.05 g (53% yield) of white needles, which were identified as N-t-butyloxycarbonyl-6-methyl-2-(α,α,α-trifluoromethyl)-(S)-tyrosine, mp 150°-152° C.; 1 H NMR analysis indicated: (δ, d 6 acetone) 7.00 (s, 1H), 6.93 (s, 1H), 5.95 (d, J=7.3 Hz, 1H, NH), 4.60-4.50 (m, 1H), 3.33 (dd, J=7 and 14 Hz, 1H), 3.23 (dd, 10 and 14 Hz, 1H), 2.43 (s, 3H) and 1.35 (s, 9H). Mass spectrum analysis indicated: (m/e) 386 (M+Na), 364 (M+H), 308, 264 and 189. Elemental analysis was performed and calculated as follows: calcd. C 16 H 20 F 3 NO 5 , C(52.89), H(5.55) and N(3.76), found C(52.78), H(5.54) and N(3.76). A small sample was deprotected, derivatized with Marfey's reagent and analyzed by HPLC and shown to be a 96/4 mixture of S and R isomers, respectively.
EXAMPLE 5
N-Butyloxycarbonyl-2,6-diethyl-(S)-tyrosine was prepared as follows: The procedures used were the same as those used to prepare N-butyloxycarbonyl-2,6-dimethyl-(S)-tyrosine in Example 1. The physical characterization of the various intermediates is listed below.
(a) 3,5-Diethyl-4-iodophenol; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.52 (s, 2H), 5.47 (br s, 1H, OH), 2.71 (q. J=7 Hz, 4H) and 1.17 (t, J=7 Hz, 6H). Mass spectrum analysis indicated: (m/e) 276 (M ) and 261.
(b) O-Methyl-3,5-diethyl-4-iodophenol; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.32 (s, 2H), 3.45 (s, 3H), 2.52 (q, J=7 Hz, 4H) and 0.98 (t, J=7 Hz, 6H), Mass spectrum analysis indicated: (m/e) 290 (M+), 275 and 105.
(c) Methyl (Z)-α-acetamido-β-(2,6-diethyl-4methoxyphenyl)acrylate; 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.02 (s, 1H), 6.62 (s, 2H), 6.57 (br s, 1H, NH), 3.78 (s, 3H), 3.74 (s, 3H), 2.50 (q, J=7 Hz, 4H), 1.91 (s, 3H) and 1.16 (t, J=7 Hz, 6H). Mass spectrum analysis indicated: (m/e) 305 (M+), 246 and 187.
(d) N-Acetyl-0-methyl-2,6-diethyl-(S)-tyrosine methyl ester; This was obtained as a 97/3 mixture of S and R isomers, respectively, from the asymmetric hydrogenation step using the [Rh(COD)(R,R-DIPAMP)]BF 4 catalyst; H NMR analysis indicated: (δ, CDCl 3 ) 6.36 (s, 2H), 6.12 (br d, J=7 Hz, 1H, NH), 4.60 (q, J=7 Hz, 1H), 3.65 (s, 3H), 3.49 (s, 3H), 2.96 (AB of an ABX, 2H), 2.59 (q, J=7 Hz, 4H), 1.89 (s, 3H) and 1.26 (t, J=7 Hz, 6H). Mass spectrum analysis indicated: (m/e) 307 (M+), 248, 177 and 43.
(e) 2,6-Diethyl-(S)-tyrosine hydrobromide salt; 1 H NMR analysis indicated: (δ, CD 3 OD) 6.48 (s, 2H), 3.91 (t, J=7 Hz, 1H), 3.22 (AB of an ABX, 2H), 2.57 (q, J=7 Hz, 4H) and 1.22 (t, J=7 Hz, 6H). Mass spectrum analysis indicated: (m/e) 238 (M+1), 163, 82 and 80.
(f) N-t-Butyloxycarbonyl-2,6-diethyl-(S)tyrosine; mp 145-145.5, 1 H NMR analysis indicated: (δ, d 6 -acetone) 6.57 (s, 2H), 6.09 (d, J=7 Hz, 1H, NH), 4.38-4.27 (m, 1H), 3.08 (dd, J=6.4 and 14.5 Hz, 1H), 3.02 (dd, J=9.2 and 14.5 Hz, 1H), 2.69 (q, J=7.0 Hz, 4H), 1.38 (s, 9H) and 1.18 (t, J=7.0 Hz, 6H). Mass spectrum analysis indicated: (m/e) 360 (M+Na), 338 (M+H), 282, 238 and 163. Elemental Analysis was performed and calculated as follows: C 18 H 27 NO 5 : C(64.06), H(8.06) and N(4.15), found: C(64.17), H(8.10) and N(4.11). The final material was shown to be a 97/3 mixture of S and R isomers, respectively.
EXAMPLE 6
N-Butyloxycarbonyl-2-ethyl-6-methyl-(S)tyrosine was prepared by the procedure used to prepare N-butyloxycarbonyl-2,6-dimethyl-(S)-tyrosine in Example 1. The physical characterization of the various intermediates is listed below.
(a) 3-Ethyl-4-iodo-5-methylphenol; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.46 (s, 2H), 5.04 (s, 1H, OH), 2.66 (q, J=7 Hz, 2H), 2.34 (s, 3H) and 1.13 (t, J=7 Hz, 3H). Mass spectrum analysis indicated: (m/e) 262 (M+), 247 and 91.
(b) O-Methyl-3-ethyl-4-iodo-5-methylphenol; 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.45 (s, 2H), 3.60 (s, 3H), 2.67 (q, J=7 Hz, 2H), 2.35 (s, 3H) and 1.17 (t, J=7 Hz, 3H). Mass spectrum analysis indicated: (m/e) 276 (M+), 261, 134, 119 and 91.
(c) Methyl (Z)-α-acetamido-β-(2-ethyl-4-methoxy-6-methylphenyl)acrylate; 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.00 (s, 1H), 6.82 (s, 1H), 6.50 (s, 2H), 3.72 (s, 3H), 3.66 (s, 3H), 2.48 (q, J=7 Hz, 2H), 2.17 (s, 3H), 1.88 (s, 3H) and 1.14 (t, J=7 Hz, 3H). Mass spectrum analysis indicated: (m/e) 291 (M.), 232, 190 and 173.
(d) N-Acetyl-0-methyl-2-ethyl-6-methyl-(S)tyrosine methyl ester; This was obtained as a 97/3 mixture of S and R isomers, respectively, from the asymmetric hydrogenation step using the [Rh(COD)(R,R-DIPAMP)]BF 4 catalyst. 1 H NMR analysis indicated: (δ, CDCl 3 ) 6.55 (br d, J=7 Hz, 1H, NH), 6.45 (s, 2H), 4.67 (q, J=7 Hz, 1H), 3.71 (s, 3H), 3.53 (s, 3H), 3.03 (AB of an ABX, 2H), 2.62 (q, J=7 Hz, 2H), 2.27 (s, 3H), 1.92 (s, 3H) and 1.17 (t, J=7 Hz, 3H).
(e) 2-Ethyl-6-methyl-(S)-tyrosine hydrobromide salt; 1 H NMR analysis indicated: (δ, CD 3 CN) 4.08 (m, 1H), 3.30 (d, J=7 Hz, 2H), 2.58 (q, J=7 Hz, 2H), 2.22 (s, 3H) and 1.12 (t, J=7 Hz, 3H).
(f) N-t-Butyloxycarbonyl-2-ethyl-6-methyl-(S)-tyrosine; mp 153-154° C., 1 H NMR analysis indicated: (6, De-acetone) 6.54 (s, 1H), 6.51 (s, 1H), 6.08 (br d, J=7 Hz, 1H, NH), 4.39-4.30 (m, 1H), 3.17 (dd, J=6.8 and 14.7 Hz, 1H), 3.01 (dd, J=8.9 and 14.7 Hz, 1H), 2.68 (q, J=7 Hz, 2H), 2.31 (s, 3H), 1.37 (s, 9H) and 1.18 (t, J=7 Hz, 3H). Mass spectrum analysis indicated: (m/e) 346 (M+Na), 324 (M+H), 268, 224 and 149; Elemental Analysis was performed and calculated as follows: C 17 H 25 NO 5 : C(63.15), H(7.73) and N(4.33), Found: C(62.25), H(7.63) and N(4.18). This material was shown to be a 99:1 ratio of S and R isomers, respectively.
EXAMPLE 7
N-Butyloxycarbonyl-2,6-dimethyl-(S)-phenylalanine This compound was prepared from 2,6-dimethyliodobenzene by the procedure used to prepare N-butyloxycarbonyl-2,6-dimethyl-(S)-tyrosine, in Example 1, except that the hydrolysis step was done using 12N hydrochloric acid. The physical characterization of the various intermediates is listed below.
(a) Methyl (Z)-α-acetamido-β-(2,6-dimethyl-phenyl) acrylate; mp 134°-135° C.; 1 H NMR analysis indicated: (δ, CDCl 3 ) 7.21-7.05 (m, 4H), 6.63 (br s, 1H), 3.89 (s, 3H) and 2.24 (s, 6H). Mass spectrum analysis indicated: (m/e) 247 (M+), 205, 188, 146 (100%) and 43.
(b) N-Acetyl-2,6-dimethyl-(S)-phenylalanine methyl ester; This was obtained as a 97.5:2.5 mixture of S and R isomers, respectively, using the Rh(COD)(R,R-DIPAMP)]BF 4 catalyst. H NMR analysis indicated: (δ, CDCl 3 ) 7.07-6.96 (m, 3H), 6.03 (br d, J=7.5 Hz, 1H), 4.87-4.76 (m, 1H), 3.62 (s, 3H), 3.17-3.03 (m, 2H) and 2.34 (s, 6H). Mass spectrum analysis indicated: (m/e) 249 (M+), 119 (100%), 88 and 43.
(c) 2,6-Dimethyl-(S)-phenylalanine hydrochloride salt; 1 H NMR analysis indicated: (δ, CD 3 OD) 7.04 (s, 3H), 4.06 (t, J=8.0 Hz, 1H), 3.37 (dd, J=8.0 and 13.9 Hz, 1H), 3.16 (dd, J=8.0 and 13.9 Hz, 1H) and 2.35 (s, 6H). Mass spectrum analysis indicated (m/e), 194 (M+, 100%), 193, 178, 148, 131 and 119.
(d) N-t-Butyloxycarbonyl-2,6-dimethyl-(S)phenylalanine; mp 136-137° C.; 1 H NMR analysis indicated: (δ, d 6 -acetone) 6.98 (s, 3H), 6.20 (br d, J=8.7 Hz, 1H), 4.46 (dt, J=6.2 and 8.7 Hz, 1H), 3.26 (dd, J=6.2 and 13.9 Hz, 1H), 3.12 (dd, J=8.7 and 13.9 Hz, 1H), 2.38 (s, 6H) and 1.35 (s, 9H). Mass spectrum analysis indicated: (m/e) 294 (M+H), 238 (100%) and 194; Elemental Analysis was performed and calculated as follows: C 16 H 23 NO 3 : C (65.51), H (7.89) and N (4.77), Found: C (65.71), H (7.97) and N (4.54); and [α]D 25 =-15.6 (c =5.6 mg/ml, EtOH. This material was shown to be a 99:1 ratio of S and R isomers, respectively. | A process for making 2,6-disubstituted tyrosine by the noble metal coupling of a disubstituted aromatic halide or diazonium salt with an amino-protected 2-aminoacrylic acid to form a (Z)-β-(disubstituted phenyl)-α-acylaminoacrylate, and asymmetrically hydrogenating the acrylate to produce the 2,6-disubstituted tyrosine. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. patent application Ser. No. 13/864,017 filed Apr. 16, 2013, now U.S. Pat. No. 9,164,810 issued Oct. 1, 2015, the contents of which are hereby incorporated by reference in its entirety.
TECHNICAL FIELD
The present disclosure relates generally to information handling systems, and more particularly to systems and methods for context-aware adaptive computing.
BACKGROUND
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
As the mobility of information handling systems increases, the need to address considerations associated with mobility also increases.
SUMMARY
In one embodiment, the present disclosure includes a method comprising receiving a request at a first information handling system (IHS) to perform an application computation. The method also includes determining the user's context, the user operating the first IHS, and ascertaining a battery state of the first IHS. The method further includes allocating the application computation between the first IHS and a second IHS based at least on the user's context and the battery state of the first IHS.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the disclosed embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:
FIG. 1 illustrates an example of a variety of information handling systems with a variety of connections, in accordance with the present disclosure;
FIG. 2 illustrates an example set of operations in accordance with the present disclosure; and
FIG. 3 illustrates an alternative example set of operations in accordance with the present disclosure.
DETAILED DESCRIPTION
The present disclosure may relate to systems and methods for context-aware adaptive computing. For example, a user at a local information handling system may be request some application computation be performed. However, in some situations it may be beneficial to shift that computation burden to a remote information handling system rather than performing it at the local information handling system, for example, when the battery of the local information handling system is low. The local information handling system may perform an analysis to determine where, from a variety of options, the optimal location is to perform the application computation. For example and in no way limiting, the analysis may consider the battery state of the local information handling system and the context in which the user is using the information handling system and/or the application.
For the purposes of this disclosure, an information handling system (IHS) may include any instrumentality or aggregate of instrumentalities operable to compute, calculate, determine, classify, process, transmit, receive, retrieve, originate, switch, store, display, communicate, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer (e.g., desktop or laptop), tablet computer, mobile device (e.g., personal digital assistant (PDA) or smart phone), server (e.g., blade server or rack server), a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components or the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, touchscreen and/or a video display. The information handling system may also include one or more buses operable to transmit communication between the various hardware components.
For the purposes of this disclosure, computer-readable media may include any instrumentality or aggregation of instrumentalities that may retain data and/or instructions for a period of time. Computer-readable media may include, without limitation, storage media such as a direct access storage device (e.g., a hard disk drive or floppy disk), a sequential access storage device (e.g., a tape disk drive), compact disk, CD-ROM, DVD, random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and/or flash memory; as well as communications media such as wires, optical fibers, microwaves, radio waves, and other electromagnetic and/or optical carriers; and/or any combination of the foregoing.
FIG. 1 illustrates an example of a variety of information handling systems (IHSs) with a variety of connections. As shown in FIG. 1 , IHS 110 may be a mobile IHS, for example, a tablet, smart phone, laptop, or some other IHS. When an application computation is requested, IHS 110 may perform an analysis to determine where to allocate the application computation to be performed, for example, whether the application computation should be offloaded to IHS 120 or 130 or should be performed locally at IHS 110 .
IHS 110 may include a processor 112 communicatively coupled to a memory 114 , a connection device 116 , and a battery 118 . IHS 120 may include a processor 122 communicatively coupled to a memory 124 and a connection device 126 . IHS 130 may include a processor 132 communicatively coupled to a memory 134 and a connection device 136 . IHSs 110 , 120 , and 130 may be in communication with each other via network 140 .
A processor, for example, processors 112 , 122 , and 132 may include any system, device, or apparatus configured to interpret and/or execute program instructions and/or process data, and may include, without limitation a microprocessor, microcontroller, digital signal processor (DSP), application specific integrated circuit (ASIC), or any other digital or analog circuitry configured to interpret and/or execute program instructions and/or process data. In some embodiments, a processor may interpret and/or execute program instructions and/or process data stored in a memory and/or another component of an information handling system. Although FIG. 1 depicts information handling systems 110 , 120 , and 130 as including one processor, information handling systems 110 , 120 , and 130 may include any suitable number of processors.
Memories 114 , 124 , and 134 may be communicatively coupled to processors 112 , 122 , and 132 respectively, and may include any system, device, or apparatus configured to retain program instructions and/or data for a period of time (e.g., computer-readable media). Memory may include random access memory (RAM), electrically erasable programmable read-only memory (EEPROM), a PCMCIA card, flash memory, magnetic storage, opto-magnetic storage, or any suitable selection and/or array of volatile or non-volatile memory that retains data after power to an information handling system is turned off. Although FIG. 1 depicts IHSs 110 , 120 , and 130 as including one memory 114 , 124 , and 134 respectively, IHSs 110 , 120 , and 130 may include any suitable number and variety of memories.
Connection devices 116 , 126 , and 136 may include any system, device, or apparatus configured to facilitate communication to or from an IHS. A connection device may include a modem, a network interface card (NIC), a wireless receiver and/or transmitter, an antenna, or other related devices to facilitate communication, or any combinations thereof. Although FIG. 1 depicts IHSs 110 , 120 , and 130 as including one connection device 116 , 126 , and 136 respectively, IHSs 110 , 120 , and 130 may include any suitable number and variety of connection devices. For example, IHS 110 may include a connection device configured to allow communication with a cellular network and a connection device configured to allow communication with a Wi-Fi or other wireless network. In some embodiments, this may be accomplished by a single connection device with multiple functionalities.
Battery 118 may include any system, device, or apparatus configured to store electrochemical, electromechanical, or other forms of energy and may provide electrical energy to one or more components of IHS 110 . In some embodiments, battery 118 may be a rechargeable battery, meaning that its electrochemical energy may be restored by the application of electrical energy (e.g., a lead and sulfuric acid battery, nickel cadmium (NiCad) battery, nickel metal hydride (NiMH) battery, lithium ion (Li-ion) battery, lithium ion polymer (Li-ion polymer) battery, smart battery, or any combination thereof, or any other suitable battery). While IHS 110 is shown as only having a single battery, it will be appreciated that any number and combination of batteries may be used. Additionally, while IHSs 120 and 130 are not shown having a battery, they may include one or more batteries. Further, while IHS 110 is shown having battery 118 , IHS 110 may additionally include an additional or alternative power source, for example, solar cells, an electric plug (for example to allow IHS 110 to be plugged into an electrical outlet), or any other source of power to allow IHS 110 to operate, or any combination thereof.
Battery 118 may have an associated battery state. This may indicate whether the battery is operational or defective, a degree of charge of the battery, a time until complete discharge of the battery, whether the battery is currently charging or not, whether the degree of charge is below a predetermined or critical threshold, or any combination thereof. For example, a current battery state of battery 118 may indicate that battery 118 is currently being used to power IHS 110 , that it is 57% charged, and that it will be completely discharged in six hours. An alternative battery state may indicate that IHS 110 is plugged into an electrical outlet so battery 118 is currently charging, that it is 58% charged, and that it will take four hours to fully charge battery 118 . As another example, the battery state may only indicate that battery 118 is below an ideal level.
Network 140 may include any network and/or fabric configured to allow communication between IHSs 110 , 120 , and 130 . Network 140 may be implemented as, or may be a part of, a storage area network (SAN), personal area network (PAN), local area network (LAN), a metropolitan area network (MAN), a wide area network (WAN), a wireless local area network (WLAN), a virtual private network (VPN), a cellular network, an intranet, the Internet, or any other appropriate architecture or system that facilitates the communication of signals, data and/or messages (generally referred to as data), or any combinations thereof. Network 140 may transmit data using any storage and/or communication protocol, including without limitation, Fibre Channel, Frame Relay, Asynchronous Transfer Mode (ATM), Internet protocol (IP), other packet-based protocol, small computer system interface (SCSI), Internet SCSI (iSCSI), advanced technology attachment (ATA), serial ATA (SATA), advanced technology attachment packet interface (ATAPI), serial storage architecture (SSA), integrated drive electronics (IDE), and/or any combination thereof. Network 140 and its various components may be implemented using hardware, software, or any combination thereof.
In some embodiments, network 140 may include a home network region 142 , an office network region 146 , and a cellular network region 144 . For example, IHS 110 and IHS 120 may be connected to a Wi-Fi router 143 providing access to home network region 142 of network 140 . As an alternative example, IHS 110 may be connected to cellular network region 144 of network 140 via one of service provider 145 a or 145 b . Service providers 145 a and 145 b may provide different speeds of access to the same or a similar cellular network, or may provide access to different cellular networks, or may provide access to cellular network region 144 at a variety of locations, or any combinations thereof. IHS 130 may be connected to network 140 via access point 147 in office network region 146 . In some embodiments, office network 146 may be a secured network. While only a small number of routers, access points, and service providers may be shown, it will be appreciated that any number and/or variety of infrastructure may be utilized in the implementation of network 140 . Additionally, it will be appreciated that any number and/or variety of regions may be included in network 140 .
One non-limiting example of how the IHSs may be connected may be that IHS 110 may be in communication with IHS 120 via a home-based Wi-Fi network. IHS 110 may be in communication with IHS 130 via a cellular network using 4G Long Term Evolution (LTE). IHS 120 may be in communication with IHS 130 via a VPN.
In some embodiments, network 140 may include physical connections or close proximity wireless connections. For example, IHS 110 may be connected to IHS 120 via a universal serial bus (USB) cable or a BLUETOOTH® connection.
IHS 110 may employ remote computing, but need not do so. For example, some portion of the computing requested at IHS 110 may be offloaded to a remote IHS like IHS 120 and/or 130 . Each of IHSs 110 , 120 , and 130 may have an associated computing capability indicating the capacity and/or capability of that information handling system to perform computing tasks. This may be based on a variety of factors, for example, the number and speed of processors, the number of applications and/or operating systems running, the amount and type of memory available on the IHS, software compatibilities, software plug-ins, video capabilities, display capabilities, power level, or any combination thereof.
Computing tasks or application computing may include any calculating, executing, processing, generating, modifying, coding, decoding, compressing, decompressing, displaying, translating, or combinations thereof utilized in conjunction with the use of an application, operating system, or other information handling system program.
In some embodiments, IHS 110 may create and maintain a database of each IHS's computing capability in memory 114 . The database may be updated on a periodic basis or on the occurrence of a pre-determined event (for example, when a decision must be made as to what IHS should perform application computing, or when IHS 110 is powered on).
In some embodiments, an application may be completely executed on a remote IHS (for example IHS 120 or 130 ) and resulting data or a display transmitted to a mobile IHS (for example IHS 110 ) and commands from the mobile IHS transmitted to the remote IHS for execution. In other embodiments, an application may be completely executed on the mobile IHS, with limited or no interaction with the remote IHS. In still other embodiments, the application computing may be divided between multiple IHSs. For example, when using a video-heavy application, the application may be processed at a remote IHS and an uncompressed video stream may be sent to the mobile IHS. Alternatively, the application may be processed and the video stream compressed and sent to the mobile IHS, and the video stream may be decompressed at the mobile IHS. Additionally, there may be varying levels of compression that may occur with a trade-off between size in video stream to be transmitted and loss in quality and/or processing required to decompress the video stream. Wherever the application computing is performed, there may be a computing cost associated with performing the application computing. This may include the power used by the IHS to perform the application computing, as well as the resource cost to perform the computing (for example, the processor cycle and/or memory blocks used to perform the application computing).
In addition to the actual application computing, data may have to be located and utilized in conjunction with the application computing. For example, if the application computing is to be performed at a mobile IHS but the data to be used in the computing is stored at a remote IHS, the data must be transmitted to the mobile IHS before it can perform the application computing. In like manner, if the application computing is to be performed at the remote IHS but the data to be used in the computing is stored at the mobile IHS, the data must be transmitted to the remote IHS before the application computing may be performed. This may be referred to as a communication cost, and may include the power required to power a communication device to communicate data, as well as the communication resources to communicate the data (for example, the Wi-Fi bandwidth or cellular data that is transmitted or received). As described above, communication costs may also include the transmission and/or reception of data produced by the application computing. Using the example from above, a video stream may be created at the remote IHS which must be transmitted to the mobile IHS.
When a user operates IHS 110 , that user may have a user context in which IHS 110 is being operated. This may include a variety of factors, including, but not limited to, the user's user style (for example, a power user, a knowledge worker, a professional nomad, a task worker, an institutional collaborator, a temporary user, or others), the user's habits and patterns of use, the connection IHS 110 has with network 140 , the connection IHS has with each of IHSs 120 and 130 , the application being used, the physical location of IHS 110 , or combinations thereof.
A user style may be based on a generic or default set of typical requirements or usage for a particular category of user. For example, a power user may require a large amount of resources because of the heavy resource-utilizing application computing performed and the number and complexity of applications employed. As an alternative example, a task worker may require a lower amount of resources because the number and complexity of applications is low. As a further example, a professional nomad may require a medium level of resources, but may require a high level of connectivity and bandwidth because of the frequent travel the user may experience. The user style may be designated by the user themselves or may be designated by some other party, for example, a system administrator. Any number and variation of user styles may be used. In some embodiments, a user style may also correspond to a default application profile that may be transmitted to IHS 110 to be stored in memory 114 or some other storage device and updated and refined as a local application profile. IHS 110 may also store the user style.
A user's habits and patterns of use may be stored or recorded as a local application profile. This may allow predictions to be made as to the style and frequency of a user's use of an IHS. For example, a particular user may check their email on their smart phone after waking up, not use their smart phone for an hour while they get ready, and then may use their smart phone continuously for an hour while they ride a train to work. The user may then stream videos during their lunch hour, and not use their smart phone again until the ride home. Saturday afternoons, the user may go for a run in a particular park and stream music from their smart phone while running Over time, patterns of use will emerge regarding the type of use (for example, business or personal), the type of application being used (for example, a web browser, a word processing program, or a software coding program), the location of use (for example, their home, their office, the train, the park), and combinations thereof. This information may be stored locally on a user's IHS as a local application profile.
The connection between IHS 110 and network 140 may be a component of the user's context. For example, and in no way limiting, at a single location, a smart phone may be connected via a home Wi-Fi network, via a 4G LTE cellular connection, or via a 3G cellular connection. The connection may have an associated speed or bandwidth and latency for both upload and download. The connection may also have an associated bit rate, error rate, or any other of a variety of factors that may contribute to the quality of service of a connection. The location of IHS 110 may also be determined in some embodiments based on the type of connection. For example, if IHS 110 is connected to a home Wi-Fi network, the location of IHS 110 is the same as the home Wi-Fi network. As an alternative example, if IHS 110 is connected to a cellular 4G LTE network, the nearest cellular tower may provide an approximate location of IHS 110 . In some embodiments, a global positioning system (GPS), triangulation, or some other means or method may be used to determine the location of IHS 110 .
The connection between IHS 110 and each of IHSs 120 and 130 may be a component of the user's context. As non-limiting examples of connections between the IHSs, IHS 110 may be connected to IHS 130 through a VPN, or a secure connection, or IHS 110 may be connected to IHS 120 through an unsecured Wi-Fi network. Alternatively, IHS 110 may be connected to IHS 120 via a BLUETOOTH® connection or a USB cable.
The application being used may be part of the user's context. For example, a user may seek to utilize a web browser, a word processing program, a database program, a spreadsheet program, a computer-assisted design (CAD) program, or any other of a variety of applications. Each application may have an associated set of application requirements. This may indicate any of a minimum or suggested operating system, processor, graphic processor, memory, disk space, software or software components, or any combination thereof. In some embodiments, not all applications to be utilized may run natively on IHS 110 .
FIG. 2 illustrates an example set of operations to be performed. At operation 210 an information handling system may receive a request at a local IHS to perform an application computation. This may include launching an application that was not previously running on the local IHS, performing a particular task in a running application, or any other application computation. At operation 220 , the user's context is determined. As described above, the user's context may be based on a variety of factors, any combination of which may be included at operation 220 .
At operation 230 , the available computation capabilities may be determined. The local IHS may recall its own computation capabilities and receive the computation capabilities of the alternative IHS. This may be performed each time an application computation is requested, or this may be periodically updated. The local IHS may maintain a database reflecting this information.
At operation 240 , the battery state of the local IHS may be ascertained. As described above, this may include a variety of factors. At operation 250 , the connection between the IHS and a network may be modified. For example, if a user is currently not connected to a network or is connected through a slow connection, the connection may be created or modified to utilize an alternative connection. This may be done to optimize the application computation. An example description of modifying the connection may be described in application Ser. No. 13/604,906, incorporated herein by reference in its entirety.
At operation 250 , the application computation is allocated between the IHS and an alternative IHS. The allocation at operation 250 may be based on a variety of factors and considerations, including but not limited to, the user context (for example, any of user style, the user's habits and patterns, the connection of the IHS with a network, the connection of the IHS with the alternative IHS, the application being used, and the location of the IHS), the battery state, a security policy, and the location of data to be used in the application computation. Some factors favor locally performing the application computation. For example and in no way limiting, a high energy state (for example, when the IHS is connected to an electrical socket or has a high battery charge), the application being available on the IHS, a low connectivity speed, a high cost of connectivity, and data required for the application computation being available at the IHS may all favor allocating the application computation to the IHS. As an alternative example, a low cost of connectivity, a low power communication means, a high resource computation, the application not being available on the IHS, and data required for the application computation only being available at the alternative IHS may all favor allocating the application computation to the alternative IHS. This may allow an IHS to adaptively determine where an application computation will be allocated.
In some embodiments, the allocation may be based on optimizing battery life for the local IHS. For example, if a communication cost in battery power will exceed the computation cost in battery power, the application computation may be allocated to the local IHS. Alternatively, if the communication cost is less than the computation cost in battery power, the application computation may be allocated to the remote IHS. In some embodiments, the battery life may be optimized subject to certain qualifications. For example, certain multi-media processing may be allocated to the local IHS for a particular application, but the remainder of application computations may be allocated to the remote IHS.
In some embodiments, a security policy may be location-based relative to the IHS and/or the data. Such a policy may prevent the transmission of data to or from an IHS based on certain aspects of the user context, for example, the location of the user. As a non-limiting example, there may be a security policy in place that secure data will not be sent to Iran for an application computation. If the user operating the local IHS is physically located in Iran and data needed for the application computation is located in the United States near the alternative IHS, the security policy may dictate that the application computation be performed at the alternative IHS rather than at the local IHS. This may be the case even if other factors may favor allocating the local IHS to perform the application computation such that all else being equal, if the same application computation were requested while the user was in the United States, it would be performed locally.
At operation 260 , alternative application computations may be performed at a different IHS than where the application computation has been allocated. For example, if the application computation has been allocated to the alternative IHS, some related or associated alternative application computations may be performed at the local IHS. In some embodiments, the local IHS may perform multi-media processing, ADOBE FLASH® processing, OPEN GL® execution, DIRECTX® execution, web browsing processing (for example, hyper text markup language (HTML) processing), JAVA® processing, voice over internet protocol (IP) (VOIP) processing, video over IP processing, other associated tasks, or any combinations thereof. This may facilitate an increased user experience for some situations. For example, a user's web browsing experience may be enhanced by allowing local processing of ADOBE FLASH® elements, or a user's video conference may provide higher quality video and audio experience when executed locally.
While operations 210 - 270 are shown in a linear fashion, it will be appreciated that these steps may be done in a different order, done simultaneously, or some steps completely omitted. For example, 230 , 250 , or 270 may all be omitted. Alternatively, operations 220 , 230 , 240 , and 250 may be done in any order. As another example, operation 230 may be performed before operation 210 .
FIG. 3 illustrates an alternative example set of operations in accordance with the present disclosure. At operation 310 , a default application profile may be received at a local IHS as a local application profile. For example, the local IHS may receive a default application profile from an alternative IHS, the default application profile based on a user style of the user operating the IHS.
At operation 320 , a request may be received for an application computation. At operation 330 , the local application profile may be updated to reflect the request for an application computation at operation 320 . The local application profile, when updated, may reflect what the application computation requested, what application (if any) was involved, the date and time of the request, the computing capability change, the location of the IHS when the request occurred, or any other information beneficial in predicting the use patterns of the user. This information may be stored in a memory of the local IHS, or some other storage device. In addition to being performed after operation 320 , operation 330 may be performed at other times to update the local application profile. For example, operation 330 may be periodically performed to update what applications are running at certain times throughout a day or week. In some embodiments, rather than proceeding to operation 340 , the process may repeatedly cycle through operations 320 and 330 , and will only occasionally proceed on to operations 340 and/or 350 .
At operation 340 , the local application profile may be transmitted from the local IHS. For example, the local application profile may be transmitted to the alternative IHS such that the alternative IHS may modify and refine the default application profile. In some embodiments, this information may be transmitted anonymously. This may only be done periodically, for example, once per month or once every three months. In some embodiments, this may be an optional feature that a user may opt into. For example, upon initialization, a user may be asked if they are willing to periodically transmit their local application profile to refine the default application profile.
At operation 350 , patterns of use of the user may be predicted based on the local application profile. For example, algebraic equations including a variable for a future event (for example, a request for an application computation) may be arranged based on the previous use reflected in the local application profile. The future event variable may then be solved for.
While operations 310 - 350 are shown in a linear fashion, it will be appreciated that these steps may be done in a different order, done simultaneously, or some steps completely omitted. For example, any of operations 310 and 340 may be omitted. Alternatively, operations 320 , 330 , 340 , and 350 may be done in any order. As another example, operation 350 may be performed before or simultaneously with operation 340 . As another example, operation 350 may be performed after operation 330 , and then the process may proceed to return to operation 320 .
In no way limiting, and merely by way of illustration, two examples are provided of how an application computation may be allocated. In one example, a user may want to run AutoCAD® from home from a work laptop. The user's AutoCAD® files may be stored at a cloud-based system at work. When the user launches AutoCAD®, the cloud-based AutoCAD® instance may be launched as it is next to their data and the communication costs of remotely running the application computation may be less than the computation cost coupled with the communication cost of retrieving the data. When the user is back in the office, when they launch AutoCAD® it may launch directly from their laptop as the laptop may now be plugged in and have a high bandwidth connection to access their AutoCAD® data. In a second example, before a user leaves for a flight, they may launch an email application from a tablet. The tablet may determine from the user's calendar that the user will be in flight shortly and so may need a mobile email application that allows an offline mode for email. Rather than launching a cloud-based instance of Outlook®, the tablet may instead launch the mobile email application. When the user connects at night from their hotel, the tablet may launch the cloud-based instance of Outlook®.
While a variety of examples have been provided and described, it will be appreciated that none of the examples is intended to be limiting. Rather, the examples are provided merely for illustrative purposes to provide assistance in understanding the present disclosure.
Although the present disclosure has been described in detail, it should be understood that various changes, substitutions, and alterations can be made hereto without departing from the spirit and the scope of the disclosure as defined by the appended claims. | The present disclosure relates to systems and methods for context-aware adaptive computing. In one embodiment, the present disclosure includes a method comprising receiving a request at a first information handling system (IHS) to perform an application computation. The method also includes determining a user's context, the user operating the first IHS, and ascertaining a battery state of the first IHS. The method further includes allocating the application computation between the first IHS and a second IHS based at least on the user's context and the battery state of the first IHS. The present disclosure also includes associated systems and apparatuses. | 8 |
BACKGROUND
1. Field of the Invention
The present invention relates to apparatus for supplying measured doses of lubricants to a lubricating line. In particular, the present invention relates to devices for dosing lubricants to a lubricating line wherein the devices of the type having at least one manual throttling element limiting the volume flow of the lubricant into the lubricating line.
2. Description of the Prior Art
Such dosing devices with manual throttling element are used for specific central lubrication tasks in the parallel distribution of lubricant flows depending upon the requirements of the machine manufacturers or operators. The manual adjustability of the manual throttling element is necessary in practice to reduce the volume flow for a specific period of time in the case of cold, highly viscous lubricants and to prevent an overflow of lubricating points in the case of a reflux which is still deficient due to the viscosity. A machine-load-dependent lubricant dosing is adjusted in each case in a relatively simple fashion. Relatively large volume flows up to about 6 1/min. are dosed to the lubricating points in body presses, large transmissions and paper machines.
In the dosing device known from the print sheet No. 01 80.03.86 of Eugen Woerner GmbH & Co., D-6980 Wertheim the flow metering device is an inspection pipe with a floating piston as sensor element, whose position determined by the volume flow is electrically monitored. The boundary values of the volume flow are entered on a scale. An LED display serves for the function control by indicating whether the floating piston has reached or exceeded a previously determined position in the inspection pipe.
The, dosing device according to the publication "Durchfluβmesser", 48715 PB1 of the DE LIMON FLUHME GmbH & Co. company, D-4000 Dusseldorf 1 works according to the same principle, an electric switching contact being actuated as a function of the position of the floating body.
These dosing devices work in a strongly viscosity-dependent fashion, i.e. they must be calibrated at a specific lubricant temperature. Static flow metering devices are concerned since the floating body remains immovable under the adjusted volume flow during operation. Several disadvantages result from this. Due to impurities contained in the lubricant and substances deposited e.g. due to the additives under thermal and mechanical load, the inspection pipe becomes clogged. A direct visual control of the position of the floating body is rendered difficult or even impossible after a longer service life. The floating body often remaining immovable for weeks gets caught due to such deposits and delivers then an "erroneous" "okay" message despite a changing volume flow. These impurities change the flow cross-sections near the floating body so that it changes its position and generates a "erroneous" fault signal, although the volume flow is correct or still within an admissible tolerance range or generates an "erroneous" "okay" signal although the volume flow is no longer correct. A serious disadvantage of these static flow metering devices is moreover the incorrect display of the volume flow and the difficult exact calibration. This is also due to the fact that the floating body only indicates whether the nominal volume flow has been reached or not reached or exceeded. In lubricating systems in which such relatively inexpensive throttling dosing devices which are easy to handle are used, this has been put up with so far as being inevitable and it was attempted by means of frequent controls and knocking against the inspection pipe to ensure a proper function and to avoid damages in the lubricating points. Therefore it has become a custom to let supervisors control all dosing devices practically daily although the adjusted volume flow is not changed for weeks or months.
Dynamic flow metering devices are known per se. According to DE-OS 29 43 184 a flow metering cell for a flowing liquid contains a gearwheel or an impeller, whose rotational speed is inductively scanned to detect the actual flow. The wheel may consist of plastic material and be equipped with permanent magnets. This principle is not suited for relatively viscous lubricants. An oval wheel meter serving as flow counter with an electric pulse transmitter on a wheel serves for determining the oil consumption of an oil burner according to DE-OS 35 11 537.
SUMMARY OF THE INVENTION
The invention is based on the object of creating a device of the type mentioned at the beginning which distinguishes itself by an increased operational reliability and a greater accuracy of dosing maintaining the advantage of constant manual adjustability and direct control at the adjustment point.
In accordance with the present invention as embodied and broadly described herein, a device as a constructional unit for the dosing of lubricants to at least one lubricating point connected to a throttling line comprises at least one manual throttling element limiting the volume flow to the lubricating point and a flow metering device connected downstream of the manual throttling element. The flow metering device contains at least one sensor element movable through the volume flow. The flow metering device is a dynamic flow metering device connected downstream of the manual throttling element and whose sensor element also moves during constant volume flow. The device further includes a display device showing the actual volume flow from the movement of the sensor element.
The dynamic flow metering device of the present invention which will be described in more detail hereinafter works with a self-cleaning effect, because movements of the sensor element take place even in the case of a volume flow remaining unchanged in the flow metering device, which prevent the depositing of impurities and the partial clogging of the flow metering device. The respective actual volume flow is exactly indicated from the movement of the sensor element. If a foreign matter gets into the dynamic flow metering device, it can possibly block or decelerate it, which is, however, immediately indicated. There is neither a "erroneous" "okay" display nor a "erroneous" fault display. This increases operational reliability, because it is definite at all times that the actual volume flow is correctly displayed in the case of all conditions, i.e. also in the case of failures, which excludes an erroneous alarm as well as uncertainties due to "erroneous" "okay" messages. Since the display means in the constructional unit permanently keeps on hold an indication derived from the dynamics of the sensor element so-to-speak on site, the volume flow can be directly controlled more exactly at the adjustment element of the manual throttling element and is above all displayed more correctly than in a static flow metering device, which depends on a static position depending on many influences. The robust and inexpensive device which is actually simple due to the manual throttlling element becomes a precise device for such high requirements due to the dynamic flow metering device, the fulfilling of which has only been possible so far with substantially more expensive apparatus structures, such as an expensive and sensitive flow limiter. Nevertheless, the device maintains the advantage of simple construction and adjustability at all times, because, strictly speaking, intervention is only carried out on the monitoring side and the accuracy and reliability of the monitoring of the effected adjustment is increased. The dynamic flow metering device has furthermore the important advantage of working largely viscosity-independent as opposed to static flow metering devices which work in an extremely viscosity-dependent fashion and can only be correctly adjusted to a certain extent in the case of the actual operating temperature of the lubricant and which do not longer display correctly in the case of changes in the temperature.
It is certainly known in lubricant technology to use relatively expensive flow limiters working proportionally in exacting lubricating problems. Each flow limiter is alone responsible for adjusting and observing the volume flow. A dynamic flow metering device can be connected downstream of these flow limiters, which is connected to a central measuring station. In the measuring station a function control is associated to each dynamic flow metering device and possibly even a display or comparator means. A direct visual control on site and on the dynamic flow metering device is only possible by means of visual control of the movement of the sensor element. However, the visual control only confirms the flowing of a volume flow without giving information on its actual dimensions. For this reason dynamic flow metering devices have so far only been used in lubricating technology in connection with flow limiters such as in DE-OS 28 24 353, in which a volume controlling valve separated from the dynamic flow metering device designed as gearwheel motor is provided as flow limiter and the actual amount is displayed via a transmission from a separately disposed display means.
Preferably, the dynamic flow metering device is a gear wheel motor with two permanently engaged spur wheels whose engagement area is in a measuring chamber and that the flow path for the volume flow extends in tangential direction of the spur wheels through the engagement area. The spur wheels being in engagement are already driven in the case of small volume flows so that the exact indication of the actual volume flow can be read. Each adjustment of the manual throttling element can be immediately read on the display means so that an exact adaption to the nominal volume flow becomes possible. If a foreign matter gets into the engagement area of the spur wheels, their movement is hindered or blocked, which ensues in an fault signal. In the case of a volume flow being unchanged for a long period of time the spur wheels produce a desirable self-cleaning effect, which eliminates the susceptibility to failures due to deposited impurities. If deposits narrow the passage, this is also displayed immediately. If the spur wheels are blocked then the fit ensured by the backlash of the teeth and the mobility of the gearwheels in the measuring chamber is sufficient for an emergency running, although there is already a failure display. The difference in pressure produced by the spur wheels is negligible and does not have any noticeable influence on the uniform supply of the luburicating point. The manual throttling element alone is responsible for adjusting and observing the volume flow. Since the gearwheels convey exactly predetermined individual volumes during their movement, which are exactly counted, the display is extremely accurate. Changes in the viscosity caused by the temperature do not have any noticeable influence on the accuracy of the display, because the same volumes are always conveyed. The display is always correct independently of the temperature of the lubricant.
It is also preferred that at least one permanent magnet is contained in at least one of the spur wheels, that a scanning means is provided with at least one scanning element aligned to the circumferential path of the permanent magnet, and that the scanning means is connected to the display means via an evaluator circuit. The gearwheel motor has here the function of a drive for the permanent magnets, whose movement is ascertained by the scanning means and can be converted to a display value representing the actual volume flow via the evaluator circuit. The conversion of the movement of the spur wheels can be effected both digitally or analoguely. The useful signals from the rotating movement of two oppositely polarized permanent magnets are exact and can be well processed to exactly indicate the volume flow. Not only each change of the volume flow is displayed, but also a volume flow being constant over long service lives.
It is still further preferred that the scanning means, the evaluator circuit, and the display means are disposed on the housing of the gear wheel motor and that a separate power supply for the scanning means, the evaluator circuit, and the display means is provided, and also that the display means is operatively connected in signal-transmitting relationship to an external measuring station. The display means can contain an LCD or LED display. The additional connection to the measuring station permits a remote control of the dosing device, although it displays failures in clearly visible fashion at all times for a direct control and represents the volume flow, which is required for the correct adjustment by means of the manual throttling element. The LCD or LED displays work reliably and insusceptibly to failures over long service lives with low energy requirements.
It is also preferred that the display means includes an alarm signal transmitter. This is furthermore important because the alarm signal transmitter displays failures which can then be eliminated immediately. A daily visual or knock control of the dosing device is superfluous, because the control persons can rely on the precision of the dynamic flow metering devices, since they are insusceptible to failures due to impurities or foreign matter inasmuch as they exactly display failures and to not emit any erroneous fault signals or erroneous "okay" signals.
And it is yet still further preferred that a plurality of dynamic flow metering devices are disposed in group-like fashion on a joint base plate containing a lubricant supply line and branch connections to lubricating lines so that the displays of the display means are at the same side, preferably the side of the manual throttling elements. At least one adjustable manual throttling element is disposed in the base plate between the lubricant supply line and each branch connection. The manual throttling element can be built into the housing of the gear wheel motor, and the scanning means, the evaluator circuit, and the display means can be disposed on the housing as an exchangeable module. The multiple device feature is significant in that a minimum of space need be utilized to monitor a lubricant flowing to several different lines. These features are furthermore important because the modular construction is advantageous in view of repairs or maintenance work and corresponds to modern construction concepts. The monitoring system of each dosing device is independently designed in customary fashion so that it emits an alarm signal during a failure, the display means possibly working with a failure coding, so that the respectively occurred failure is displayed and can be rapidly eliminated. If a failure occurred for instance in one of the components of the dosing device, e.g. a mechanical defect in the gearwheelmotor or a shortcircuit in one of the electrical or electronic components, then the faulty component can be rapidly replaced as a modular component. Here, as well, the dynamic flow metering device can bring to bear its characteristic given due to the dynamics to be able to differentiate between different failure causes.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the subject matter of the invention is explained by means of the drawing.
FIG. 1 shows a section through a dosing device and FIG. 2 shows a front view of a dosing device group with outlined sectional plane.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
For the parallel distribution of large volume flows of lubricant a group B of dosing devices Z for at least one lubricating point in each case is provided according to FIGS. 1 and 2, each dosing device Z representing a constructional unit of its own in the group B. A manual throttling element D serves for adjusting the volume flow, to which a dynamic, optoelectronic flow metering device M is connected downstream in the direction of flow. At least one sensor element S is provided in the flow metering device M, which can be moved through the volume flow of lubricant. A scanning means T is associated to the sensor element S, which is connected to a display means A via an evaluator circuit 15.
In a base plate 1 common to all provided dosing devices Z, which contains a central supply line 2, several branch lines 3 fork of from the same. The inflow to each branch line 3 is adjusted by the manual throttling element D. It has a locking screw 4 for the throttling element 6, which is screwed into a threaded bore 5, which cooperates in customary fashion with a receiver 7. An axial screwing of the throttling element 6 effects a change of the throttle cross-section and thus of the volume flow in the lubricating line.
A housing 8 of the dynamic flow metering device M which is allocated to the manual throttling element D is screwed onto the base plate 1. A gearwheel motor 9 with two permanently engaging spur wheels 21, 21a is provided in a measuring chamber 12 in the housing 8. A connection 10 leads from the branch line 3 to the measuring chamber 12. A connection 11 serves for connecting the lubricating line. The connection 11 could also end in the base plate 1, to which the lubricating line is then connected. At the inspection side of the flow metering device M the measuring chamber 12 is closed by an inspection glass 13 which is sealingly fixed to the housing 8 by means of a retaining ring 23. A scanning element 14 is held in a housing bore 28 which extends in parallel to the rotational axis of the two spur wheels 21, 21a, which is part of the scanning means T. The scanning element 14 is in a signal-transmitting connection with the evaluator circuit 15, which is built into the housing 8, which is supplied with current via a line 16a and a plug 16. The evaluator circuit 15 is furthermore in signal-transmitting connection with the display means A, which has a display 18 (LED or LCD display) at the inspection side of the inspection glass 13 of the housing 8. The evaluator circuit 15 or the display means A is connected with a measuring station W locally separated from the dosing means Z via a line 16b.
The spur wheels 21, 21a are rotatably mounted in the bottom 20 with plug-type axles 19. The spur wheel 21 serves as a driving element for diametrally opposite axis-parallel permanent magnets 22 with opposite polarities. The scanning element 14 is aligned to their orbits. Several scanning elements may also be provided for a higher resolution.
The spur wheels 21, 21a support a radial toothing 24 and have a joint engagement area 25 approximately in the centre of the measuring chamber 12, through which the volume flow flows from the connection 10 to the connection 11 approximately tangentially to both spur wheels 21, 21a. The measuring chamber 12 has an approximately kidney-shaped contour with two opposite swells 26, into wich part of the circumference of each spur wheel 21, 21a is fitted with small backlash. The inspection glass 13 and the bottom 20 of the measuring chamber 12 are in alignment with the front sides of the two spur wheels 21, 21a so that the lubricant is forced to flow to the engagement area 25. Since the pressure reduction by means of the swells 26 is effected in a different fashion than via the meshing teeth in the engagement area 25, the gearwheel motor 9 is driven in such fashion in FIG. 2 that the lower spur wheel 21 is rotated clockwise and the upper spur wheel 21a is rotated counter-clockwise. The scanning element 14 is suitably a Hall sensor which is activated as a function of the rotational speed of the spur wheels 21, 21a and emits useful signals. The signals are processed in the evaluator circuit 15. The display on the actual volume flow appears constantly in the display field 18 of the display means A. The signals of the evaluator circuit 15 or also of the Hall sensor 14 can be transmitted to the measuring station W via line 16b. The actual condition is continuously represented and compared with a nominal value for all partial volume flows in the measuring station.
A signal transmitter 27 is mounted on the display means A, which is either activated from the measuring station W or via the evaluator circuit even in the case of a failure, e.g. in the case of an inadmissible exceeding of or dropping below the nominal volume flow. The display means A could also work with an failure coding, by means of which the respective cause of the failure is displayed in coded form. For this purpose the evaluator circuit 15 could be equipped with a comparator, which can be adjusted at the dosing device Z by inputting parameters when required.
The display means A could be built into the housing 8. It is furthermore conceivable to build the manual throttling element D also into the housing and to design the individual components, i.e. both the manual throttling element, the scanning means T, the evaluator circuit 15 and the display means A as modules which can be exchanged, if required. As a further possibility the base plate 1 could be divided into sectors, one sector each being integrated into the housing 8. Then, too, the group-like joining of several dosing devices on a minimum of space is possible. Nevertheless, the possibility is preserved to check each dosing device optically already by a glance to the inspection glass 14 as regards function and by a glance to the display 18 as regards the volume flow. Upon the adjustment of the manual throttling element D, it can be immediately detected at all times on the display 18 how the volume flow is changed. This is suitable if e.g. during the starting phase of a machine an overflooding of the lubricating points must be avoided in the case of a viscosity-inherent and still deficient reflux of the lubricant or if an adaptation to the machine load is effected in the case of a machine-load-dependent dosing changing the volume necessary for normal operation. The manual throttling element D could also be composed for a coarse and a fine throttle.
The spur wheels 21, 21a consist suitably of a non-magnetic material, e.g. a plastic material, which is dimensionally stable and resistant against the lubricant and has good endurance run properties. Due to the running movement of the two spur wheels 21, 21a the inspection glass 13 is automatically freed from impurities settling from the lubricant. Thermally highly loaded lubricants such as oils tend to deposit additives or impurities resulting from the reaction between additives and other substances in the case of long service lives. These deposits can narrow the flow ducts in the extreme case. The gearwheel motor 9 is insusceptible to such influences and works independently of viscosity in a desirable fashion. Several gearwheel motors may also be accommodated in one and the same housing. Since the display 18 anyhow displays the proper function of the gearwheel motor besides the exact indication of the actual volume flow, the inspection glass could be omitted and the housing could be designed in closed fashion, which possibly ensues in production-technique advantages. | In a device for the dosing of lubricants which comprises at least one manual throttling element limiting the volume flow and a flow metering device connected downstream of it, which contains at least one sensor element movable through the volume flow, a dynamic flow metering means (M) is connected downstream in the manual throttling element (D) whose sensor element (S) moves also after the reaching of the nominal volume flow and a display means (A) is provided on the dynamic flow metering device (M), which represents the actual volume flow from the movement of the sensor element (S). | 5 |
BACKGROUND OF THE INVENTION
In drilling boreholes for the production of hydrocarbons, it is necessary to install a casing which extends from the surface of the earth to an elevation located downhole in a borehole. The annulus between the borehole wall and the exterior of the casing must be completely filled with cement, thereby preventing communication between various strata through which the borehole extends.
There are cementing tools known to those skilled in the art which can be manipulated to provide bypass from a medial portion of the casing string directly into the borehole annulus. These tools are expensive, complex in design, and often must be drilled after the cementing operation has been completed.
It is therefore desirable to have made available a cementing tool which is simple in design, positive in operation, and which is fabricated in such a way that there is no need to drill a passageway through the interior of the tool after the cementing operation has been completed.
SUMMARY OF THE INVENTION
This invention relates to downhole tools and specifically to a cementing tool which is series connected into a string of casing for enabling cement to be pumped down the string and thereafter laterally through the tool where the cement flows directly into the borehole annulus. The tool is thereafter moved to the closed position by manipulating the upper casing string, and left downhole as a permanent part of the string.
The tool includes a sub by which one end thereof can be connected into the casing string, a sealed, fluid-conducting latch means, a mandrel, and a barrel.
The latch means includes a receptacle which latchably engages a hollow sleeve so that a hollow flow conduit results. The mandrel and sub include opposed marginal ends by which the tool can be connected in series relationship within the string of casing. The barrel includes opposed ends which are connected to the sub and to the mandrel such that the mandrel, barrel, and sub are concentrically arranged respective to one another.
A threaded interior surface is formed within the barrel which cooperates with a similar threaded surface formed on an exterior marginal length of the mandrel, thereby enabling the mandrel to be threadedly disengaged from the barrel.
The sleeve and the receptacle are mounted in spaced relationship adjacent opposed ends of the barrel.
When the barrel is rotated respective to the mandrel, the threads therebetween are disengaged, thereby enabling the mandrel to be telescoped into the barrel to thereby form an annular area between the barrel and the mandrel. The annular area forms the lateral flow passageway from the interior of the tool into the borehole annulus. The mandrel is subsequently telescoped further into the barrel to cause the sleeve and receptacle to mate, thereby locking the components of the tool together.
A primary object of the present invention is to provide a cementing staging tool which is manipulated by the upper casing string to open and thereafter close a lateral flow passageway in the tool.
Another object of the invention is to provide a cementing staging tool which need not be drilled after the cementing job has been completed.
A further object of this invention is to disclose and provide a cementing tool which is left downhole as part of a casing string after the casing has been cemented to the borehole.
A still further object of this invention is the provision of a tool which is run into a borehole as part of a casing string, and is manipulated by the upper casing string to laterally flow cement into the borehole annulus, and which avoids the necessity of being drilled after the cementing operation has been completed.
The above objects are attained in accordance with the present invention by the provision of both method and apparatus for cementing casing into a borehole in a manner which avoids the necessity of subsequently drilling through the tool.
These and various other objects and advantages of the invention will become readily apparent to those skilled in the art upon reading the following detailed description and claims and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 diagrammatically illustrates the tool of the present invention disposed downhole in a borehole;
FIG. 2 is an enlarged, exploded view of part of the apparatus disclosed in FIG. 1;
FIG. 3 is an enlarged, fragmented, part cross-sectional view of the tool disclosed in FIG. 2;
FIGS. 4 and 5 are similar to the view illustrated in FIG. 3 and show the tool of the present invention in various dif ferent operative configurations;
FIG. 6 is a fragmented, part cross-sectional view of another embodiment of a tool made in accordance with the present invention;
FIG. 7 is an enlarged, fragmented, part cross-sectional view of part of the apparatus disclosed in FIG. 6;
FIG. 8 is a cross-sectional view taken along line 8--8 of FIG. 6;
FIG. 9 discloses the tool of FIG. 6 in a different operative configuration;
FIG. 10 is a cross-sectional view taken along line 10--10 of FIG. 6;
FIG. 11 is a fragmented, part cross-sectional view of another embodiment of a tool made in accordance with the present invention;
FIG. 12 discloses a method of cementing a borehole in accordance with the present invention;
FIG. 13 is an enlarged, elevational view of part of the apparatus disclosed in FIG. 12; and,
FIG. 14 is a cross-sectional view taken along line 14--14 of FIG. 13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 diagrammatically discloses the surface 10 of the ground through which a borehole 12 has been formed, and within which there is disposed a tool string comprised of an upper casing string 14 and a lower casing string 16. Numeral 18 broadly indicates a cementing tool made in accordance with the present invention, which connects together the upper and lower casing string.
The tool of the present invention is comprised of an upper member 20 which is operatively connected to a lower member 22. Numeral 24 indicates the lower extremity of the tool, while numeral 26 indicates the upper extremity thereof. Numeral 28 indicates an interface formed between the upper and lower members. Numerals 30 and 32, respectively, indicate the lower and upper extremity, respectively, of the casing. The borehole annulus 34 is formed between the exterior of the casing and the wall of the open borehole.
As seen illustrated in FIG. 2, in conjunction with FIGS. 1 and 3-5, the upper member of the tool includes a barrel 36 which threadedly engages a sub 38 by means of the illustrated threads 37 and 39. A sleeve 40 is provided with an external threaded surface 42 which threadedly engages the lower internal threaded surface of the sub. Split snap ring 44 is received within a circumferentially extending groove 45 formed about the external marginal surface of the sleeve. A seal means is formed at the lower marginal end of the sleeve and is comprised of a plurality of O-rings 46 fitted within a series of spaced O-ring grooves.
The lower member 22 is in the form of a hollow, cylindrical mandrel having an external thread 48 formed at the upper marginal end thereof which threadedly engages complementary threads formed on the lower marginal interior surface of a hollow receptacle 50. The receptacle has a circumferentially extending inside peripheral wall surface 47. A threaded external surface 52 is formed at the lower marginal end of the hollow receptacle which threadedly engages a complementary threaded surface 52' formed on the lower, internal, marginal end of the barrel.
FIG. 3 illustrates the above embodiment of the tool of the present invention assembled in the running-in configuration, as broadly disclosed in FIG. 1. The sleeve 40 is seen to be spaced from the receptacle 50 with the threads 52 and 52' being engaged with one another. Hence, the tool of FIG. 3 provides a sealed flow path from the upper into the lower casing string.
FIG. 4 illustrates the tool of FIGS. 1-3 in the alternate configuration, wherein the tool has been manipulated so that cement can be pumped down the upper string and laterally out into the borehole annulus.
As seen in FIG. 4, threads 52, 52' have been parted by rotating the upper member or barrel 20 respective to lower member or mandrel 22 by imparting rotational motion into the upper casing string. After threads 52, 52' have parted, the upper string is lowered, thereby moving the barrel in a downward direction so that flow can occur from the interior of the tool, through the newly opened annulus 54, where the flow exits the tool at 28 and flows out into the borehole annulus. Hence, the tool of FIG. 4 is in the cementing or operative configuration.
FIG. 5 illustrates the tool after it has been latched into the completed configuration. As seen in FIG. 5, the sleeve 40 has been lowered so that the snap ring 44 has been forced into the groove 45', thereby latching the receptacle and the sleeve together. At the same time, seal means 46 sealingly engage the slightly outwardly tapered wall 47 of the receptacle so that flow from the interior of the tool into the annulus 54 is precluded.
In operation, the tool 18 is assembled in the run-in configuration of FIG. 3. The tool is then series connected within the upper and lower casing strings and positioned downhole in the borehole at a predetermined elevation. A limited quantity of cement is pumped through the entire tool string where a plug of cement is formed about the casing in proximity of lower end 30. After an interval of time during which the plug "sets", the upper string 14 is rotated clockwise, thereby screwing threads 52 and 52' apart, whereupon the upper string and barrel can be lowered a few inches into the cementing or operative configuration of FIG. 4.
Cement is again pumped down the upper casing string and into the interior of the tool. From the interior of the tool, the cement is forced along the newly opened annulus 54 and emerges at 28 and fills the borehole annulus 34. Often the pumping of cement will continue until the cementatious material surfaces at 10.
Before the borehole annulus is completely filled with cement, water is generally pumped into the upper casing string so that the interior of the casing is flushed clean of cement, and a savings in money is effected.
Before the cement hardens, the upper casing string is again lowered to effect relative motion between the barrel and the mandrel so that the lower marginal end of sleeve 40 is received within receptacle 50. This action causes the tool to assume the configuration illustrated in FIG. 5 wherein the snap ring 44 is received within groove 45', with the multiple seal means 46 sealingly engaging the inside peripheral surface 47 of the receptacle. This action permanently closes the annular passageway 54 so that lateral flow can no longer occur therefrom.
The first embodiment of the invention disclosed in FIGS. 2-5 provides a positive means by which a casing can be cemented within a borehole by merely manipulating the upper casing string. Since the cementing tool of the present invention is hollow and provided with a minimum inside diameter equivalent to the nominal inside diameter of the casing string, there is no need to drill out the interior of the tool.
The presence of the barrel provides a guide means at 28 with respect to the mandrel 22 for proper alignment of the latch means. Moreover, there is never any danger of the casing being parted, because the two adjacent ends of the casings are always tied together in a positive manner by the tool of the present invention. The snap ring and the groove provide a latch means which is dependable and of adequate strength to prevent the upper and lower casing string from parting.
Where deemed desirable, the upper sub 38 and sleeve 40 can be fabricated as a unitary member. Likewise, the receptacle 50 and mandrel 22 can be fabricated as a unitary member if desired. The annulus 54 can be enlarged by changing the relative diameters of the remaining components of the tool to effect a cross-sectional area or annulus as may be desired.
In the embodiment of the invention disclosed in FIGS. 6-10, the snap ring 44 is caged in compressed configuration by a cage assembly generally indicated by the numeral 60. As seen in the detail of FIG. 7, the cage includes a downwardly directed skirt 62 which enlarges into a shoulder at 64 so that the assembly can more or less encapsulate and force the split ring 44 back up into its groove 45. Shear pin 65 prevents inadvertent movement of the cage assembly.
As the barrel moves downward relative to the mandrel, the upper terminal end of the receptacle engages the skirt of the cage at 62, thereby shearing pin 65 and forcing the cage to slide up the sleeve. This action releases snap ring 44 as it slidably enters the interior of the hollow receptacle.
A plurality of radially spaced-apart, frangible plugs 66, 68, and 70 threadedly engage the sidewall of the barrel. The plugs are hollow and when the closed interior end thereof is broken, the interior of the barrel is placed in direct communication with the borehole annulus, thereby providing a lateral passageway from the interior of the tool into the borehole annulus.
Numeral 75 broadly illustrates a positive latch means which is utilized in this embodiment of the invention to augment the latch action of the ring 44 and groove 45'. The positive latch 75 is affixed at 76 to the mandrel by welding. The latch includes a continuous, circumferentially extending skirt portion 78 having a threaded surface 80 formed thereon. The threaded surface is provided with a plurality of radially spaced-apart, parallel slots 82, which extend from the lower edge 84, up through the threads, where the slots terminate within the skirt 78. The slots 82 impart the individual, elongated, tab-like members with resiliency so that the individual members can be sprung inwardly toward the mandrel. The threaded surface 80 is made complementary with respect to the threaded surface 52'; and therefore, when the tool is manipulated into the completed configuration of FIG. 9, the tab-like members are sprung inwardly so that the assembly 75 is forced to be telescopingly received by the threaded lower marginal end of the barrel. Accordingly, when the upper casing string is set down, latch 44 engages groove 45', and at the same time, latch member 75 is slidably received in a forceful manner into the lower marginal end of the barrel, thereby causing the tool to assume the configuration illustrated in FIG. 9.
In operation, the tool is placed in the running-in configuration of FIG. 6 and run downhole into the borehole in the before described manner. The tool is rotated and manipulated into the configuration described in conjunction with FIG. 4 of the drawings. This action causes the upper terminal end of the receptacle to engage and break the closed ends of the plugs 66, 68, 70 which fall to the bottom of the borehole. Shearing of the plugs provides a plurality of radially spaced ports which form a lateral flow passageway in the barrel in addition to the formation of the annulus at 54 through which fluid can flow from the interior of the tool laterally out into the borehole annulus.
After the borehole annulus is filled with cement, the upper string is lowered so that the tool assumes the configuration illustrated in FIG. 9. As the seal means of the sleeve 40 is received within the receptacle, the upper terminal end of the receptacle engages the skirt 62 of the cage assembly, thereby shearing pins 65 and forcing the cage to move in an upward direction in the illustrated manner of FIG. 9. This expedient enhances the locking action by assuring that the split ring 44 is positively received within the groove 45' of the receptacle.
As the tool approaches the configuration illustrated in FIG. 9, the positive latch means 75 is forced to ride in high friction relationship across the threads 52 of the barrel until the threads mutually engage one another in the illustrated manner of FIG. 9. It will be noted that the threads 80 are sloped in a downward direction, thereby providing minimum friction as the member 75 is forced to slide up into the barrel. At the same time, the threads are downwardly sloped so that a maximum of friction is developed when the upper and lower members are placed in tension respective to one another.
In the embodiment of the invention disclosed in FIG. 11, the positive latch means is attached to the mandrel in overlying, concentric relationship respective to the barrel. The upper marginal end of the barrel threadedly engages the mandrel at 152 so that the mandrel may be rotated respective to the barrel in order to disengage the threads at 152 from one another.
The lower end of the sleeve engages and breaks the closed end of the plugs 66, 68, and 70 as the tool is lowered into the cementing configuration. Annulus 187 can be made of any desired cross-sectional area, depending upon the relative diameters of the components of the tool and the minimum and maximum inside diameters available for selection. Where deemed desirable, the plugs 66-70 can be made shorter and located within annulus 187 so as to preclude breakage thereof should it be necessary to run various tools downhole through the tool string of the invention. In this instance, shoulder 151 will engage and break the closed ends of the plugs.
In FIG. 11, the seal means 46 is received in seated relationship against the tapered, internal peripheral wall surface of the receptacle similar to the before described embodiments.
In the embodiment of the invention illustrated in FIGS. 12-14, spaced plugs 15 and 115 are pumped down the casing string by means of the illustrated pump. The suction side of the pump is flow connected to tanks T1 and T2, which generally will contain a source of cement and a source of water. The interior of the casing at 114 contains a column of water which is separated from a column of cement 214 by means of plug 15. The cement 214 is separated from a column of oil at 314 by means of a plug 115.
As seen in FIGS. 13 and 14, the plug 15 or 115 is of a diameter which conforms the inside diameter of the casing. The plug 15 is made of a substance such as soap which is solubilized by the water 114 after a few hours. The plug 115 is made of a substance such as wax which is solubilized by the hydrocarbons at 314 after a few hours.
Accordingly, in carrying out this aspect of the invention, after the tool string has been run downhole into the borehole, the plug 115 is placed within the upper end of the casing and forced down to the bottom of the tool 118, thereby maintaining the column of cement separated from the fluid column of the hydrocarbons. The plug 115 eventually is solubilized by the hydrocarbons so that it offers no subsequent problems.
Toward the end of the cementing operation, when it is desired to force the remaining cement out of the interior of the casing, the plug 15 is interposed between the column of cement and a column of water 114. The water is utilized to force the plug 15 down into the tool. This action maintains the water column and the mass of cement separated from one another and further, reduces the amount of cement left behind on the interior wall surface of the casing.
The cementing tool of the present invention can be series connected into a string of casing 14 and 16 and used for cementing the casing string within a borehole 12 by flowing cement down the string 14, into the tool 18, and into the borehole annulus 34.
The tool includes a sub 38, a mandrel 22, a barrel 36, a sleeve 40, a receptacle 50, all concentrically arranged respective to one another along a common central axis as in the before described manner. The barrel has opposed ends with one marginal end being affixed to the sub 38 and the remaining marginal end being affixed to the mandrel 22.
The threads 52, 52' provide means by which one marginal end of the barrel can be disengaged from the mandrel to enable the mandrel to be moved axially towards the sub. The sleeve is affixed to either the sub or the mandrel, while the receptacle is affixed to either the barrel or the sub. The barrel has a threaded surface which is disengaged to permit the mandrel and barrel to move axially towards one another, whereupon the sleeve is received within the receptacle in the illustrated manner of FIGS. 5 and 9, for example.
Latch means 44 and 45 are provided by which the sleeve is locked in sealed relationship respective to the receptacle when the mandrel is moved longitudinally respective to the sub.
A secondary latching means 75 is provided for engagement with one of the before mentioned threads so that as the sleeve is locked in sealed relationship respective to the receptacle, the secondary positive latching means likewise is permanently attached to the recited threaded surface.
The sleeve and receptacle are hollow and form an axial flow path through the tool, while the annulus located between the barrel and mandrel form a lateral flow path from the tool. | A cementing staging tool for use downhole in a borehole which is interposed in a casing string and manipulated by longitudinal and rotational movement of the upper casing string. The tool enables cement to be pumped down through the string of casing to form a lower plug. The upper casing string is then rotated and thereafter lowered to thereby open a lateral flow passageway through which cement can be pumped. The cement flows through the tool and fills the borehole annulus, thereby cementing the casing string to the borehole wall. The tool is closed by lowering the upper marginal length of the casing string.
The tool maintains the ends of the casing string in captured relationship respective to one another at all times, and is left downhole as a permanent part of the casing string after the cementing operation has been completed. | 4 |
FIELD OF THE INVENTION
[0001] The invention belongs to the field of the gene engineering technology, and refers to a preparation method and the application of a tumor-targeted TNF-related apoptosis-inducing ligand's variant.
BACKGROUND OF THE INVENTION
[0002] TNF-related apoptosis-inducing ligand (TRAIL) is one of the superfamily of the tumor necrosis factors. Similarly with others of the superfamily, soluble TNF-related apoptosis-inducing ligand is trimer, and is bound with the trimer of the acceptor molecules on the surface of the target cells to play biological action. The apoptosis-inducing action of the TNF-related apoptosis-inducing ligand is realized by transmitting death information with Death Receptors 4 (DR4) and Death Receptors 5 (DR5) in the tumor cells to each other. Although, the application of numbers of the superfamily of the tumor necrosis factors is limited because of their general toxic effect, the TNF-related apoptosis-inducing ligand is a relatively safe antitumorigenic substance which has tumor selective. In vitro, TNF-related apoptosis-inducing ligand can induce lots of tumor cells and cancer cells to apoptosis, and has preferable anti-rumor activity in the xenograft of the mouse tumor, comprising of the cancer of colon, breast carcinoma, multiple myeloma, neuroglioma, carcinoma of prostate. More importantly, TRAIL shows little or no toxicity, when administered generally to mouse and non-human primates. For the above mentioned reasons, the use of the recombinant tumor necrosis factors in treating tumor is studied in clinic.
[0003] Recently, some reports indicated that, besides of inducing rumor cells to apoptosis, also, the TNF-related apoptosis-inducing ligand relates to the natural immune and acquired immune, and the autoimmune disorders. For example, the recent research reported that it play a vital role in adjusting the negative selection and apoptosis of the thymocyte cells during the development of thymus, and inducing the autoimmune disorders, such as type I diabetes mellitus. Additionally, the receptor of the TNF-related apoptosis-reducing ligand can be expressed universally in the whole body, and the TNF-related apoptosis-reducing ligand also participates in the death of the hepatic cells and hepatitis. So it will bring unpredictable immune results if large dose of exogenous TNF-related apoptosis-inducing ligand's protein is administered repeat and generally in clinic. Because of these reports, scientists feel anxious about the potential toxic effect result from repeat and lasting administration of the TNF-related apoptosis-inducing ligand in clinic. In the potential application of the TNF-related apoptosis-inducing ligand (TRAIL) in clinic, it is a difficult problem faced to avoid the toxic effect to other tissue of the TNF-related apoptosis-inducing ligand.
SUMMARY OF THE INVENTION
[0004] To overcome the drawback of the wild TNF-related apoptosis-inducing ligand in the oncotherapy, the purpose of the invention is: providing a tumor-targeted TNF-related apoptosis-inducing ligand's variant, and delivering it into tumor tissues to improve the curative effect of the TNF-related apoptosis-inducing ligand and reduce its toxic effect, so that it is possible to use in the treatment of tumorous diseases.
[0005] It is verified by researches, the aminopeptidase N (APN)/CD13 protein is expressed in the endothelial cells of the new vessels of tumors (Pasqualini R, Koivunen E, Kain R etc., Cancer Res, 2000, 60:722-727). There is very little expression of the CD13 in the resting and normal endothelial cells of the vessels. Recently, the relation of the aminopeptidase N/CD13 with the tumor metastasis and prognosis has been discovered (Haraguchi N, Ishii H, Mimori K etc., J Clin Invest., 2010, 120:3326-3339; Fontijn D, Duyndam M C, van Berkel M Petc., Br J Cancer, 2006, 94:1627-1636; Fujii H, Nakajima M, Saiki I etc., Clin Exp Metastasis, 1995, 13:337-344).
[0006] To achieve the aims of the targeted delivery of the TNF-related apoptosis-inducing ligand into tumor tissues, the improvement of the curative effect, the reduction of the toxic effect, the present invention is realized by the following technical scheme: A tumor-targeted TNF-related apoptosis-inducing ligand's variant, which is a protein with the amino-acid residue sequence of SEQUENCE 1 in the sequence list; it is a fusion protein of a TNF-related apoptosis-inducing ligand's variant consisting of the ligand of CD13, the connecting peptide, TNF-related apoptosis-inducing ligand by the method of the gene engineering, i.e., by artificially synthesis or recombination of the coding gene of the TNF-related apoptosis-inducing ligand's variant, soluble recombination expression and simple separation and purification, using normal method of the gene engineering. Wherein, the ligand of CD13 can be a polypeptide with NGR sequence, perfectly is a polypeptide with ring structure and NGR sequence, such as short peptide of CNGRC.
[0007] A short peptide of amino acid with flexible construction and non-branched chain can be added into the tumor-targeted TNF-related apoptosis-inducing ligand's variant consisting of the mentioned ligand of CD13 and the TNF-related apoptosis-inducing ligand, wherein, the short peptide has 1˜25 amono-acid residues and mainly consisting of the amino without branched chain such as glycocoll, alanine, serine, etc.
[0008] When the mentioned ligand of CD13 is situated at the N-end, an amino acid, mainly alanine or glycocoll, without branched chain is added before the ligand of CD13, to avoid the degradation at the N-end during expression and to affect the function of the ligand of CD13.
[0009] The synthesized tumor-targeted TNF-related apoptosis-inducing ligand's variant which is consisted of the ligand of CD13 and TNF-related apoptosis-inducing ligand has a good application in preparation of the drugs for tumor therapy. The drugs for tumor therapy prepared by the tumor-targeted TNF-related apoptosis-inducing ligand's variant can be used in oncotherapy together with existing chemotherapy, radiotherapy, treatment by Chinese herbs, biotherapy, etc.
[0010] Furthermore, a method of soluble expression in Escherichia Coli and simple method of separation and purification for a large of high-purity polymer of the tumor-targeted TNF-related apoptosis-inducing ligand's variant. The expression of the tumor-targeted TNF-related apoptosis-inducing ligand in the Escherichia Coll is mainly inclusion body product without biological activity at present, however, the structure and the molecular of the tumor-targeted TNF-related apoptosis-inducing ligand's variant of the present invention is more complicated than the mild TNF-related apoptosis-inducing ligand, so that there will be more inclusion body generated, and the purification is more difficult. In the present invention, an expression method of the tumor-targeted TNF-related apoptosis-inducing ligand's variant with culture and induced expression at low temperature is used, so that the generation of the inclusion body in the expression production is avoid efficiently. Simultaneously, according to the biological function of the TNF-related apoptosis-inducing ligand, the present invention obtains high-purity protein production by the binding of the ion exchange chromatography and metal affinity chromatography that makes the tumor-targeted TNF-related apoptosis-inducing ligand's variant purifying efficiently. And the purity production has high percentage of polymer, so that has favorite biological activity. Wherein, the low temperature is 35˜100.
[0011] The CD13 express in the endothelial cell of the tumor new vessels only, so there is very little expression in the resting normal endothelial cell of vessels. The recent research indicated that, CD13 protein is effect by basic fibroblast growth factor (bFGF) and high-selectively express in the surface of tumor cells such as 1 F6 malignant mela noma, and is closely related to the malignant invasion and metastasis of tumor. We analyzed the expression level of CD13 in different cells by flow cytometer, and the results indicate that: there is high expression of CD13 in endothelial cell of human micrangium, and also high expression of CD13 in Hela tumor cell that is one of human cervical caner cells, moderate expression of CD13 in colon cancer cells HCT-15, minute quatity or no expression of CD13 molecule in colon cancer cells COLO-205. The mentioned tumor-targeted TNF-related apoptosis-inducing ligand's variant consisting of the ligand of CD13 and TNF-related apoptosis-inducing ligand can significantly improve the distribution of the TNF-related apoptosis-inducing ligand in tumor tissues, achieve the targeted delivery of the TNF-related apoptosis-inducing ligand in tumor tissues, significantly improve the anti-tumor effect of the TNF-related apoptosis-inducing ligand, significantly reduce the dose of the TNF-related apoptosis-inducing ligand simultaneously.
[0012] Simultaneously, the present invention discloses a cDNA of the tumor-targeted TNF-related apoptosis-inducing ligand's variant. It can be prepared by add coding ligand of CD13 and DNA sequence of connecting peptide to the dDNA of the TNF-related apoptosis-inducing ligand. The mentioned cDNA of the tumor-targeted TNF-related apoptosis-inducing ligand's variant can be used for gene therapy.
[0013] The tumor-targeted TNF-related apoptosis-inducing ligand's variant can be modified by the method of acidulate by polyethylene glycol and fatty acid, recombination by adding anti-body Fc fragment or x-protein, etc. to prolong the half-life of the TNF-related apoptosis-inducing ligand and obtain more favorite pharmacokinetic effect.
[0014] Compared with existing TNF-related apoptosis-inducing ligand, the present invention has the following beneficial effects:
(1) more favorite tumor-targeting characteristics: The relative selectivity of the existing TNF-related apoptosis-inducing ligand to tumor tissues mainly rely on the display of the death Receptors 4 and death Receptors 5 express in tumor tissues. However, the tumor-targeted TNF-related apoptosis-inducing ligand's variant of the present invention achieve the targeted delivery of the tumor-targeted TNF-related apoptosis-inducing ligand's variant into the tumor tissues, not only relying on the death Receptors 4 and death Receptors 5 express in tumor tissues, but also relying on the tumor characteristics of high expression of CD13. (2) more favorite anti-tumor effect: Because of the targeted delivery among tumor tissues of the TNF-related apoptosis-inducing ligand, the tumor-targeted TNF-related apoptosis-inducing ligand's variant of the present invention, whether compared with the same dose of TNF-related apoptosis-inducing ligand, or compared with the variant RGD-L-TRAIL of integrins αVβ3,αVβ5 that is targeted to the surface of tumor cells (Chinese invention patent, application No.200710133862.1), shows more favorite anti-tumor effect where used separately or together with the existing methods of chemotharepy, radiotherapy, treatment by Chinese herbs, bioremediation. (3) less dosage of administration: Because of the more favorite anti-tumor effect of the tumor-targeted TNF-related apoptosis-inducing ligand's variant, compared with the same dose of NF-related apoptosis-inducing ligand, when used, the dosage of administration of the protein of the tumor-targeted TNF-related apoptosis-inducing ligand's variant is significantly reduced in the case of ensuring the anti-tumor effect. The reduction of the dose of administration of the protein of the tumor-targeted TNF-related apoptosis-inducing ligand's variant can be overcome the potential toxic effect of the TNF-related apoptosis-inducing ligand when used in oncotherapy, and also can reduce the therapy cost of tumor patients, to obtain the favorite effect, low toxic effect, low cost to oncotherapy,. (4) easy to expression and preparation: Different from the fusion protein of the tumor-targeted TNF-related apoptosis-inducing ligand targeted by tumor cell specific antibogy and the fragment thereof, the present invention combines the TNF-related apoptosis-inducing ligand and the short peptide of CD13, and the increase of molecular is limited. It is more beneficial to the gene cloning, expression and preparation of the tumor-targeted TNF-related apoptosis-inducing ligand's variant, and the yield is higher. (5) soluble expression and simple preparation and purification: The expression of the tumor-targeted TNF-related apoptosis-inducing ligand in the Escherichia Coli is mainly inclusion body without biological activity at present, however, the structure and the molecular of the tumor-targeted TNF-related apoptosis-inducing ligand's variant of the present invention is more complex than the mild TNF-related apoptosis-inducing ligand, so that there will be more inclusion body generated, and the purification is more difficult. In the present invention, an expression method of the tumor-targeted TNF-related apoptosis-inducing ligand's variant with culture and induced expression at low temperature is used, so that the generation of the inclusion body in the expression production is avoid efficiently. Simultaneously, according to the biological function of the TNF-related apoptosis-inducing ligand, the present invention obtains high-purity protein production by the binding of the ion exchange chromatography and metal affinity chromatography that makes the tumor-targeted TNF-related apoptosis-inducing ligand's variant purifying efficiently. The present invention can obtain the purity production with high percentage of polymer by soluble expression and simple separation and purification, to resume that the product has favorite biological activity. The present invention can prepare the tumor-targeted TNF-related apoptosis-inducing ligand's variant with high percentage of polymer, which is the obvious difference from the similar studies. The present invention provides a expression method and purification process of tumor-targeted TNF-related apoptosis-inducing ligand's variant which can obtain the effective expression and high content of polymer efficiently. (6) A amino acid without branched chain is added at the N-end of the ligand of CD13, so that the degradation of amino acid at N-end can be avoided efficiently, which will be effect the function of the ligand of CD13.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 , the analysis of the purified and recombinant human TNF-related apoptosis-reducing ligand and variant thereof.
[0022] 1 A, the analytic result of SDS-PAGE: 1) tumor-targeted TNF-related apoptosis-reducing ligand's variant targeting to CD13 (NGR-L-TRAIL); 2) human TNF-related apoptosis-reducing ligand; 3) human TNF-related apoptosis-reducing ligand's variant targeting to the integrins of αVβ3 and αVβ5 (RGD-L-TRAIL).
[0023] 1 B, the analytic result of non-reduced and native PAGE: 1) tumor-targeted TNF-related apoptosis- reducing ligand's variant targeting to CD13 (NGR-L-TRAIL); 2) human TNF-related apoptosis-reducing ligand (TRAIL); 3) human TNF-related apoptosis-reducing ligand's variant targeting to the integrins of αVβ3 and αVβ5 (RGD-L-TRAIL).
[0024] FIG. 2 , the analysis of the binding of green fluorescently labeled human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant thereof (NGR-L-TRAIL) with human microvascular endothelial cells, by flow cytometer.
[0025] NGR-L-TRAIL and TRAIL thereof, RGD-L-TRAIL, bovine serum albumin (BSA) as reference protein are labeled by the fluorescein. The human microvascular endothelial cells (HDMVEC) are labeled by 1 μg of labeled protein for 1 hour.
[0026] FIG. 3 , the analysis of the expression of the CD13 and integrins of αVβ3 and αVβ5 on the surface of COLO-205 cells.
[0027] 3 A: the analysis of the expression of CD13;
[0028] 3 B: the analysis of the integrin αVβ3;
[0029] 3 C: the analysis of the integrin αVβ5.
[0030] FIG. 4 , the analysis of the dose-effect relationship of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) thereof to reduce the apoptosis if the tumor cells.
[0031] 4 A: Hela cells;
[0032] 4 B: CLO-205 cells;
[0033] 4 C: HCT-15 cells.
[0034] FIG. 5 , the analysis of the effect of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) thereof to activity of the enzymes of Caspase-8 and Caspase-3 of the positive Hela cells of CD13.
[0035] 5 A: Caspase-8;
[0036] 5 B: Caspase-3.
[0037] The cells is treated separately by tumor-targeted variant NGR-L-TRAI and RGD-L-TRAIL which concentration gradient is 10˜270 ng/ml for 8 hours. After inducing, the cells are lyses on ice, and fluorogenic substrate is add to react for 1 hour, and then the analysis is carried out by microplate reader (excitation wavelength is 400 nm, emission wavelength is 505 nm).
[0038] FIG. 6 , the efficiency against to tumor of the human. TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) monotherapy in COLO-205 tumor model and the efficiency of that combined treatment with CPT-11 in COLO-205 tumor model. 6 A: the monotherapy of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) and RGD-L-TRIAL; 6 B: the combined treatment of the human TNF-related apoptosis-reducing ligand and the variant thereof with CPT-11. The results of statistical analysis are showed by average numbers, wherein, the variance is standard error, the asterisk * indicates p<0.05; and two asterisks ** indicates p<0.01.
[0039] FIG. 7 , the efficiency against to tumor of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) monotherapy in COLO-205 tumor model and the efficiency of that combined treatment with CPT-11 in HT-15 colon tumor model.
[0040] 7 A: the monotherapy of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL);
[0041] 7 B: the combined treatment of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) thereof with CPT-11. The results of statistical analysis are showed by average numbers, wherein, the variance is standard error, the asterisk * indicates p<0.05; and two asterisks ** indicates p<0.01.
[0042] FIG. 8 , the efficiency against to tumor of the human TNF-related apoptosis-reducing ligand (TRAIL) and the tumor-targeted variant (NGR-L-TRAIL) thereof used alone and together with CPT-11 in the HT-29 colon tumor model that is insensitivity to TRAIL.
[0043] FIG. 9 , the comparison of the targeted enrichment effect of the human TNF-related apoptosis-reducing ligand (TRAIL) and the variant (NGR-L-TRAIL) thereof, and RGD-L-TRAIL in the tumor tissue of COLO-205 animal model of tumor.
[0044] 100 μl/5 mCi of the human TNF-related apoptosis-reducing ligand and the tumor-targeted variant protein thereof are administrated separately by tail intravenous injection to nude mouse with COLO-205 tumor. Tumor tissue is stripped and weighed when 5, 30, 60, 120 and 240 minutes after the injection separately. The radiation quantity of isotopes in the tumor tissue is detected by liquid scintillation counter, wherein, the unit of the radiation quantity of the tumor tissue is the percentage of the detected radiation quantity in the injection radiation quantity, based on one gram of tissue (% ID/g). All results are average values of three experiments separately.
[0045] FIG. 10 , the detected distribution of the human TNF-related apoptosis-reducing ligand (TRAIL) and the variant (NGR-L-TRAIL) thereof labeled by 125 I isotope in the animal tissue.
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
[0046] The Preparation of the Tumor-Targeted TNF-Related Apoptosis-Inducing Ligand's Variant
[0047] Based on the crystal structure of the TNF-related apoptosis-inducing ligand, the short peptide of the ligand of CD13 is added to the N-end of the TNF-related apoptosis-inducing ligand, by computer aided structure modeling and molecule design, and by SGI computer workstation where the molecule design softwares (the module of InsightII, Discover etc.) of MSI company are utilized. And the amino acid length of the connecting peptide is determined by molecule modeling and molecule design.
[0048] Based on the molecule design mentioned above, firstly, we choose the design scheme where the connecting peptide has 5 glycocolls, because the computer modeling indicates that: the connecting peptide is short in this scheme, so that it will significantly affect the protein structure of the TNF-related apoptosis-inducing ligand and the binding of the CD13 and the ligand thereof. The connecting peptides in other schemes almost make a distance between the ligand of CD13 and the molecule surface of the TNF-related apoptosis-inducing ligand, so that the disturbance and the effect are light.
[0049] We also try the tumor-targeted TNF-related apoptosis-inducing ligand's variant where the alanine or glycocoll, the short peptide of alanine-glycocoll-glycocoll-serine-serine-glycocoll-glycocoll-glycocoll as connecting peptide is expressed, and the tumor-targeted TNF-related apoptosis-inducing ligand's variant with 25 amino-acid residues that contain the mentioned three repeat glycocoll-(alanine-glycocoll-glycocoll-serine-serine-glycocoll-glycocoll-glycocoll)3, and similar results are obtained. That verifies the correction of the computer molecule design. Comparatively, the expression level of the TNF-related apoptosis-inducing ligand's variant is highest (100 mg/L) when 5 cysteines are added, and others are lower, but are between approximate 50-100 mg/L.
[0050] During the computer aided molecule design of the tumor-targeted TNF-related apoptosis-inducing ligand's variant, based on the crystal structure of the TNF-related apoptosis-inducing ligand, we plan the molecule modeling and molecule design on the amino acid sequence and the length of the connecting peptide between the TNF-related apoptosis-inducing ligand and the ligand of CD13, by the structure modeling and molecule design of the tumor-targeted TNF-related apoptosis-inducing ligand's variant, to determine the amino acid length of the connecting peptide. The results indicate that: during computer molecule design, among the short peptide length of 1-25 amino acids, if the short peptide is consisted of the flexible amino-acid residue without branched chain, such as glycocoll, alanine, serine etc, neither the structure of the TNF-related apoptosis-inducing ligand, nor the function of the ligand of CD13 will be affected in any way. Under the short peptide length of 25 flexible amino-acid residues without branched chain, the excitation to the structure of the TNF-related apoptosis-inducing ligand is slighter when the short peptide length is smaller. Comparatively, if the length is too small, there will be some effect to the structure of the TNF-related apoptosis-inducing, and the binding of the CD13 and the ligand thereof will be affected too.
[0051] The gene of the wild human TNF-related apoptosis-inducing ligand is prepared by the reverse transcription of RNA that obtained from human placenta. The nucleotide sequences of the PCR primers of the gene of the TNF-related apoptosis-inducing ligand's variant bound CNGRC short peptide are:
[0000]
Primer1:
5′-GGAATTCCATATGTGCAATGGTCGTTGCGGTGGTGGTGGTGT
GAGAGAAAGAGGTCCTCAG-3′;
Primer2:
5′-ATGGATCCTTAGCCA ACTAAAAAGGCCC-3′.
[0052] By PCR reaction, the gene of the tumor-targeted TNF-related apoptosis-inducing ligand's variant (NGR-L-TRAIL) with coding CNGRC short peptide and connecting peptide consisted of 5 glycocolls is obtained. The gene of the tumor-targeted TNF-related apoptosis-inducing ligand's variant (NGR-L-TRAIL) is cloned into the pET-23a expression vector of Novagen Company, and the obtained recombinant expression plasmid is expressed in Escheichia coli BL21(DE3). To obtain the soluble expression of the tumor-targeted TNF-related apoptosis- inducing ligand's variant NGR-L-TRAIL, the expression conditions are of the following: the overnight growth recombinant expression bacteria are diluted by 100 times in LB culture medium, and are cultured for 2.5 hours at 37 □, and then cultured for 1-2 hours at 24 □; IPTG is added at 24 □ to its concentration of 0.5 mM, and then the induced expression is carried out at 24 □ overnight. After the centrifugal separation, the bacteria are suspending in lysate (50 mM sodium phosphate, 0.5 M sodium chloride, 1 mM dithiothreitol, pH 7.6) and disrupted by ultrasonic wave.
[0053] The protein of the recombinant tumor-targeted TNF-related apoptosis-inducing ligand's variant NGR-L-TRAIL is purified by supernatant passing SP-sepharose cation resin and 300 mM NaCl elution peak is collected. The eluted protein is further purified by affinity chromatography with Ni—NTA agarose gel as medium, wherein the protein is eluted by 250 mM imidazole and desalinated by Sephdex G-25. The water used in the experiment is super-purity water with endotoxin removed. The quantity of the protein is determined by BCA protein assay kit provided by Nanjing JianCheng Bioengineering Institute. The protein purity and molecular weight of the TNF-related apoptosis-inducing ligand and the tumor-targeted variant thereof are determined by Silver Staining of SDS-PAGE, and the molecular weight is identified by mass spectral analysis (Applied Biosystems 4700 Proteomics Analyzer).
[0054] The configuration, expression and purify of the variant RGD-L-TRAIL of integrins αVβ3,αVβ5 are executed in according with the Chinese invention patent application 200710133862.1.
[0055] In the last reports, the wild TNF-related apoptosis-inducing ligand expressed in the escherichia coli often is the form of inclusion body product without biological activity, but the tumor-targeted TNF-related apoptosis-inducing ligand's variant of the present invention, to which 4 cysteines are added (i.e. two disulfide bond), can generate inclusion body more easily when expressing in the escherichia coli, comparing with the wild TNF-related apoptosis-inducing ligand, so the purification is more difficult. By the modification of the expression condition and separation and purification, the present invention achieves the soluble expression of the tumor-targeted TNF-related apoptosis-inducing ligand's variant. And because of the purification by the cation exchange resin chromatography and Nickel metal affinity chromatography, high purity protein of the tumor-targeted TNF-related apoptosis- inducing ligand's variant with biological activity is obtained, and the yield is 100 mg/L. Both the analysis ( FIG. 1A ) of Silver Staining of 15% Polyacrylamide Gel Electrophoresis under the condition of denaturation and reduction and the sequencing analysis by Mass sepctrography identify the correction of the expression product. The ratio of the polymer in the TNF-related apoptosis-inducing ligand and the variant thereof is high ( FIG. 1B ), that is rare in the expression and purity of the TNF-related apoptosis-inducing ligand and the similar works.
[0056] All the proteins of the superfamily of the TNF have the characteristics of forming monomer, dimer and trimer, and the biological activity of which rely on the dimer and trimer, as well as the TNF-related apoptosis-inducing ligand. To determined whether the binding of the CNGRC will affect the ability of forming polymer of the tumor-targeted TNF-related apoptosis-inducing ligand's variant, non-reduction natural polyacrylamide gel electrophoresis is carried out and the analyst result indicate that: the protein of the TNF-related apoptosis-inducing ligand and the tumor-targeted variant thereof have the ability of forming polymer. The results show that all of the TNF-related apoptosis-inducing ligand and the tumor-targeted variant thereof and RGD-TRAIL appear three strips corresponding the molecular weight of approximate 20000, 40000, and 60000 daltons. And the three strips represent the monomer, dimer and trimer separately ( FIG. 1B ). That indicates that: the protein of the TNF-related apoptosis-inducing ligand and the tumor-targeted variant that are expressed and purified by the present invention has correct spatial structure and better biological activity than the reported TRAIL expressed in the Escherichia coli in the past.
Embodiment 2
[0057] The Experiment of the Binding of the TNF-Related Apoptosis-Inducing Ligand and Endothelial Cells
[0058] TNF-related apoptosis-inducing ligand and tumor-targeted variant thereof NGR-L-TRAIL, and RGD-L-TRAIL are labeled by fluorescein (Sigma Company) separately, and the nomadic fluorescein is removed from the labeled proteins by the molecular sieve Sephadex-G25. After the digestion by parenzyme, the endothelial cells of human foreskin microvascular are washed by cold phosphate buffer containing 2% of fetal bovine serum, and then are suspended again. 1 μg of labeled protein is added, and incubation on ice is carried out at 4 □ for 1 hour. The stained cells are washed for 3 times and analyze the binding ability by Flow Cytometer (Becton Dickinson Company) with Bovine Serum Albumin labeled by fluorescein as control.
[0059] We also evaluate the ability of the TNF-related apoptosis-inducing ligand and tumor-targeted variant thereof labeled by fluorescein, and TRAIL variant NGD-L-TRAIL (Chinese invention patent number: ZL200710133862.1) targeted to the integrins of αVβ3, αVβ5 to bind with the endothelial cells of human foreskin microvascular directly. The detect results of the Flow Cytometer indicate that: the tumor-targeted TNF-related apoptosis-inducing ligand's variant NGR-L-TRAIL has a more stronger ability to bind with the endothelial cells of human foreskin microvascular than the TRAIL variant RGD-L-TRAIL targeted to the integrins of αVβ3, αVβ5. That indicates that: the short peptide of the ligand of CD13 can improve the ability of the tumor-targeted TNF-related apoptosis-inducing ligand's variant to bind with the endothelial cells; and even the ability of the tumor-targeted TNF-related apoptosis-inducing ligand's variant to specifically bind with the endothelial cells is more stronger than the ability of the TRAIL variant RGD-L-TRAIL targeted to the integrins of αVβ3, αVβ5 to specifically bind with the endothelial cells ( FIG. 2 ). There being CD13 and integrins of αVβ3, αVβ5 during the expression in endothelial cells of human microvascular are found by different researchers, but firstly, in the present invention, the abundance of the CD13 and integrins of αVβ3, αVβ5 in the endothelial cells of human microvascular are compared and the present invention find that the expression abundance of CD13 is larger than the abundance of integrins of αVβ3 and αβ5 significantly, and further find that CD13 is a kind of more favorite directed target molecule to the endothelial cells of human microvascular than integrins of αVβ3 and αVβ5. Integrins of αVη3 and αVβ5 are the most recognized marker of new vessels internationally, and the aglucons containing RGD sequence are widely used as the probe for diagnosing the early growth of tumor and the early metastasis of the tumor. In present invention first proves that CD13 is a kind of more favorite directed target molecule than integrins of αVβ3 and αVβ5, and CD13 as tumor target will bring more favorite effect than integrins of αVβ3 and αVβ5. That is a result out of the expectation of the scientists of this field, and a result out of our expectation, so that one of important innovations of the present invention.
Embodiment 3
[0060] The Analysis of the Expression of CD13 and Integrins of αVη3 and αVβ5
[0061] The expression abundance of CD13 and the integrins on the surface of cells are detected by Flow Cytomter according to the indirect labelling method. Wherein, the digested cells washed by cold phosphate buffer containing 2% of Fetal Bovine Serum, and after being suspended again, the cells are sandwiched by anti-human CD13 monoclonal antibody (eBioscience Company) or anti-human αVβ3 integrin antibody MAB23C6 (eBioscience Company) or anti-human αVβ5 integrin antibody MAB 1961 (Chemicon International Company) for 1 hour on ice, with purified isotype mouse immunoglobulin G (eBioscience Company) as negative control. After being washed twice, the cells sandwiched by primary antibody are labeled by adding secondary antibody of sheep anti mouse immunoglobulin G1 (γ) (Caltag Laboratories) coupling green fluorescein for 30 minutes in the dark. The cells are washed 3 times and fixed in phosphate buffer containing 4% of formalin. The expression abundances of CD13 or the integrins of αVβ3 and αVβ5 are detected by Flow Cytometer, and all the staining experiments are repeated 3 times.
[0062] CNGRC, which is the ligand of CD13 that can form two disulfide bonds, and contain the ring structure and NGR sequence, has favorite affinity and selectivity to CD13. Because the target is designed towards to CD13 in the present invention, the expression results of CD13 on the surface of endothelial cells and tumor cells are analyzed by us, and the analysis results indicate that: there is high expression level of CD13 on the surface of human foreskin microvassular endothelial cells, and even the expression level of the CD13 on the surface of human foreskin microvassular endothelial cells is higher than the expression level of integrins of αVβ3 and αVβ5. Furthermore, it is important to note that: there are expressions of CD13 in different tumor cells in varying states, wherein, there are high expression level of CD13 in HDMVEC and Hela, intermediate abundance of expression of CD13 in colon cancer cell HCT-15, very little or no expression of CD13 in colon cancer cell COLO-205.
[0063] CD13 and integrins of αVβ3 and αVβ5 are expressed on the surface of tumor vasculars and tumor cells, however, which is a better tumor targeting target when comparing CD13 and integrins of αVβ3 and αVβ5? Nobody did detailed research and comparison about that. In the present invention, the expression levels of CD13 and integrins of αVβ3 and αVβ5 on the surface of tumor vasculars and tumor cells are be compared, and anti-tumor activity of the NGR-L-TRAIL which is the TRAIL variant targeted to CD13 and the NGR-L-TRAIL which is the TRAIL variant targeted to integrins of αVβ3 and αVβ5 is analyzed at the level of cellular level and animal model level and a surprising result that is contrary to the expectation is found. By comparison of the expression of CD13 and integrins of αVβ3 and αVη5 on the surface of COLO-205, we find that: there very little expression of CD13 on the surface of COLO-205, but there are low expression level of integrin αVβ3 and high expression level integrin αVβ5 ( FIG. 3 ). Correspond to that, the activity of inducing COLO-205 to apoptosis of TRAIL variant NGR-L-TRAIL targeting to CD13 is increased by a little ( FIG. 5B ), and the activity of inducing COLO-205 to apoptosis of TRAIL variant NGR-L-TRAIL targeting to integrins αVβ3 and αVβ5 is increased by 10 times (towards to COLO-205 cell, the 50% effective concentration of TRAIL is 3.5 ng/ml, the 50% effective concentration of RGD-L-TRAIL is 0.37 ng/ml). Hence, considering whether expression level in the target on the surfaces of COLO-205 cells, or the increase level of 50% effective concentration of NRG-L-TRAIL and RGD-L-TRAIL towards to COLO-205 cells, RGD-L-TRAIL is much superior to NGR-L-TRAIL. But in the COLO-205 tumor model experiment in vive, the anti-tumor effect of NGR-L-TRAIL is significantly superior to RGD-L-TRAIL when used with the same dosage, and even the anti-tumor effect of 1/5 times dosage (20 μg) of NGR-L-TRAIL is equivalent to the anti-tumor effect of 5 times dosage (100 μg) of RGD-LTRAIL. The results clearly tell us that: the anti-tumor activity of the anti-tumor drugs can not be arrived by conclusion and deduction based on the activity got form the experiment in vitro and our normal logic and understanding, but should be checked gradually through scientific experiment without ostentation, and each experiment of this procedure should not be ignored. In the present invention, many experiments in vitro show that the anti-tumor activity of RGD-L-TRAIL is significantly superior to NRG-LTRAIL, but the opposite result is got from anti-tumor experiments of tumor animal model in vivo.
Embodiment 4
[0064] Detecting the Cell Apoptosis by Double Staining Method of Annexin (Annexin V) and Propidium Iodide
[0065] The cells treated by the TNF-related apoptosis-inducing ligand and the tumor-targeted variant thereof NGR-L-TRAIL, and RGD-L-TRAIL are digested by trypsase and suctioned off culture plate, and after being washed twice by phosphate buffer, the cells are centrifugalize by 300 g of centrifugal pull for 5 minutes. The supernatant is removed and the cells are suspended again by 100 μl binding buffer. Annexin V-FITC (BD Pharmgen Company) is added to which final concentration is 2 μg/ml, and the cells are incubated at the room temperature. 10 minutes later, 400 μl binding buffer is supplemented. The cells are transferred into Flow Analyzer Tube, and 1 μg propidium iodide (Sigma Company) is added into each of the tube. The cells are analyzed by Flow Cytometer within 30 minutes. The experiment is repeated three times for each cell line.
[0066] The activity to induce the tumor cell apoptosis of the tumor-targeted TNF-related apoptosis-inducing ligand's variant NGR-TRAIL is appraised using COLO-205, HCT-15 and HT-29 cells separately ( FIG. 4 ). After induced by series concentration gradient TRAIL variant or TRAIL, the tumor cells are detected by Flow Cytometer according to the double staining method of Annexin V-FITC and Pl. The result shows that: the sensibility of different tumor cells to TRIAL is diversity, wherein, COLI-205 cells are most sensitive, HCT-15 cells are the secondary, Hela cells are not sensitive relatively. However, in Hela cells, the activity to induce tumor cells apoptosis of the NGR-L-TRAIL is increased significantly. The 50% effective concentration (EC50) of NGR-L-TRIAL to Hela cell is approximate 18.5 ng/ml, the 50% effective concentration (EC50) of TRAIL to Hela cell is approximate 145 ng/ml. The sensibility of Hela cell to TRAIL is increased 8 times because of the addition of the short peptide. To COLO-205 and HCT-15, the activity to induce tumor cells apoptosis of NGR-L-TRAIL is higher than the one of TRAIL a little. There is a positive correction between the difference of the apoptosis-inducing to these tumor cells between NGR-L-TRAIL and TRAIL and the expression and the abundance of the CD13 molecule on the surface of tumor cell. In the Hela tumor cells in which the expression level of CD13 is high, the activity to induce the tumor cells apoptosis of NGR-L-TRAIL is increased significantly. The NGR domain from NGR-L-TRAIL can direct the protein of TRAIL variant to the surface of target cell to enrichment on the cell surface. The result from that is the increasing of the local concentration of tumor-targeted TNF-related apoptosis-inducing ligand's variant, thus the TNF-related apoptosis-inducing ligand that is a part of the variant molecule can be closed to TRAIL receptor easily, frequently and efficiently so that the signal to active the pathways of apoptosis is enhanced and the activity of NGR-L-TRAIL is increased. And also, the enhance of increase of the activity to induce the apoptosis relies on the abundance of the expression of CD13 on the surface of the tumor cells, wherein, the higher abundance, the higher activity, and vice versa. For example, in the Hela tumor cells expressing CD13 highly, because of the overexpression of CD13, the activity of NGR-L-TRAIL is increased by 8 times ( FIG. 4 ). Contrary, the activity of NGR-L-TRAIL is increased little in COLO-205 colon cancer cells expressed CD13 lowly. The results above clearly indicate that: the increase of the activity of tumor-targeted TNF-related apoptosis-inducing ligand's variant results from the targeting of CNGRC.
Embodiment 5
[0067] Detecting the Enzyme Activities of Caspas-8 and Caspas-3
[0068] The enzyme activities of Caspas-8 and Caspas-3 are detected by Fluorometric Assay Kit (Oncogene Company) according to the experiment method provide by the company. The fluorescence value is detected by Microplate Reader, wherein, the fluorescent parameters are: 400 nm of excitation wavelength and 505 nm of emission wavelength.
[0069] Different from tumor cells, even the normal endothelial cells of human foreskin, 293T kidney cells and primary-cultured hepatocytes are treated by the tumor-targeted TNF-related apoptosis-inducing ligand's variant which concentration is 300 ng/ml for 24 hours, there is no significant cytotoxicity being found. The result shows that the tumor-targeted TNF-related apoptosis-inducing ligand's variant can distinguish the normal cells from tumor cells, and induce tumor cells to apoptosis, however is safe to normal cells.
[0070] We detected the activity of Caspase-8 and Caspase-3 in Hela cells that are treated by TNF-related apoptosis-inducing ligand and the tumor-targeted variant thereof, by fluorometry. Compared with the same dosage of TRAIL, NGR-L-TRAIL shows higher activity of Caspase-8 and Caspase-3 ( FIG. 5A , 5 B). It indicates that, because NGR main of NGR-L-TRAIL can direct TRAIL variant protein onto the surface of the targeting cells to enrichment on the surface of the cells, the local concentration of tumor-targeted TNF-related apoptosis-inducing ligand's variant increases. Thus, the TNF-related apoptosis-inducing ligand that is a part of variant molecule can more easily, frequently and efficiently close to TRAIL acceptor, to increase the signal to active the pathways of apoptosis. In the mutated Jurkat cells from FADD −/− and Caspase- −/− , the inducing apoptosis cannot be detected when TNF-related apoptosis-inducing ligand and the variant thereof used. It indicates that, TNF-related apoptosis-inducing ligand, as well as the variant thereof, plays a role in inducing apoptosis by means of acceptor-FADD-Caspase-8.
Embodiment 6
[0071] The Experiment of Anti-Tumor Effect in Tumor Animal Model
[0072] The female nude mice bought from ShangHai Experiment Animal Center are 5-6 weeks old. The mouse tail intravenous injection of 100 μg of purified Asialo GM-1 antibody (Wako Chemicals Company, Japan) that is specific antibody blocking natural killer cells is carried out first. 24 hours later, 100 thousands of COLO-205, HT-15 and HT-29 colon cancer cells is subcutaneously vaccinated at the top right side of the back of a mouse. When the volume of tumor arrives 70 cubic millimeters, the mice are grouped randomly and treated. The recombinant TNF-related apoptosis-inducing ligand and its targeted variant NGR-TRAIL, and the protein of RGD-L-TRAIL variant are intraperitoneally injected once a day continued for 10 to 14 days. Hydrosoluble camptothecin CPT-11(11-hydroxyl-camptothecin, trade name: Campto, from Pharmacia/Upjohn Company) is administrated by intravenous administration once a week, for twice in all. The recombinant protein and camptothecin are diluted by phosphate buffer. The volume of tumor is detected by vernier caliper and calculated according the formula: length is multiplied by the square of width and then is divided by 2.
[0073] Two colon cancer models of COLO-205 and HT-15 are utilized to detect and compare the anti-tumor activity of TNF-related apoptosis-inducing ligand and its tumor-targeted variant NGR-L-TRAIL in athymic nude mice. Because of the sensitivity of COLO-205 and HCT-15 colon cancer cells to TRAIL (wherein COLO-205 is more sensitive), we assessed the treatment effect of NGR-L-TRAIL and TRAIL separately in two models. As shown in FIGS. 4 and 6 , NGR-L-TRAIL inhibited the tumor growth significantly and the growth inhibitory activity to tumor of it is higher than that of the wild TRAIL and RGD-L-TRAIL.
[0074] In the COLO-205 model, the growth inhibitory activity to tumor of 100 μg/day dosage of NGR-L-TRAIL is far better than 100 μg/day dosage of wild TRAIL (p<0.01); and the growth inhibitory activity to tumor of 100 μg/day dosage of NGR-L-TRAIL is far better than 100 μg/day dosage of RGD-L-TRAIL (p<0.01) (p<0.05), and even the dosage of NGR-L-TRAIL is cut down to the 1/5 times (20 μg/day) of the wild's, the growth inhibitory activity to tumor is better than the one of the wild TRAIL (100 μg/day) (p<0.05); and the growth inhibitory activity to tumor of 20 μg/day dosage of NGR-L-TRAIL is nearly to the growth inhibitory activity to tumor of 100 μg/day dosage of RGD-L-TRAIL ( FIG. 6 ).
[0075] In the HCT-15 model, the growth inhibitory activity to tumor of NGR-L-TRAIL is better than wild TRAIL (p<0.01), and better than RGD-L-TRAIL too(p<0.05), at the same dosage (400 μg/day); and, when its dosage is cut down to the 1/5 times (80 μg/day) of the dosage of wild TRAIL, its growth inhibitory activity to tumor is equal to the one of the wild TRAIL (400 μg/day) (there is no significant difference between them) ( FIG. 7 ). The growth inhibitory activity to tumor of NGR-L-TRAIL of the dosage of 80 μg/day is nearly to the growth inhibitory activity to tumor of RGD-L-TRAIL of the dosage of 400 μg/day. During the treatment, the growth inhibitory activity to tumor of NGR-L-TRAIL relies on the dosage.
[0076] The results above show that: the combination of CNGRC with TRAIL significantly increases the anti-tumor activity of TRAIL, in vivo; furthermore, anti-tumor effect of NGR-L-TRAIL significantly exceeds the one of RGD-L-TRAIL.
[0077] The anti-tumor effect of tumor-targeted TRAIL used together with chemotherapeutic drug CPT-11 is researched in the present invention. Through COLO-205, HC-15 and HT-29 models of athymic nude mice, the anti-tumor effect of NGR-L-TRAIL used together with chemotherapeutic drug CPT-11 is researched, wherein, COLO-205, HC-15 are sensitive to TRAIL, and COLO-205 is most sensitive, and HT-29 is insensitive to TRAIL. The protein of NGR-L-TRAIL or TAIL is intraperitoneally injected once a day for two weeks, and CPT-11 is tail intravenously injected once every two days up to 7 injections.
[0078] In the group of combining administration, for COLO-205 model that is sensitive to TRAIL, a less dosage of CPT-11 (6.25 mg/kg per time) is administrated with different dosage of NGR-L-TRAIL (30 or 80 μg/day per mouse) or TRAIL (270 μg/day per mouse or 90 μg/day per mouse); for HT-29 colon cancer model that is insensitive to TRAIL, a larger dosage of CPT (25 mg/kg per time) is administrated with NGR-L-TRAIL or TRAIL (400 μg/day per mouse).
[0079] In COLO-205 model, the growth inhibitory activity to tumor of the group in which NGR-L-TRAIL which dosage is 30 μg/day is administrated combining with CPT-11 which dosage is 6.25 mg/kg per time is stronger than that of the group in which NGR-L-TRAIL is administrated lonely with the dosage of 30 μg/day (p<0.05); is equal to that of the group in which TRAIL which dosage is 270 μg/day is administrated combining with CPT-11 which dosage is 6.25 mg/kg per time; and is stronger than that of the group in which TRAIL which dosage is 90 μg/day is administrated combining with CPT-11 which dosage is 6.25 mg/kg per time (p<0.05) ( FIG. 6 ).
[0080] In HCT-15 model, the growth inhibitory activity to tumor of the group in which NGR-L-TRAIL which dosage is 80 μg/day is administrated combining with CPT-11 which dosage is 6.25 mg/kg per time is stronger than that of the group in which CPT-11 which dosage is 6.25 mg/kg per time or NGR-L-TRAIL which dosage is 80 μg/day is administrated lonely; and is stronger than that of the group in which TRAIL which dosage is 400 μg/day per mouse is administrated combining with CPT-11 which dosage is 6.25 mg/kg per time ( FIG. 7 ). It is worthy mentioning that, in the group in which NGR-L-TRAIL which dosage is 400 μg/day per mouse is administrated combining with CPT-11, at the 28 th day, there are 8 tumor disappeared mice from the 10 administrated mice; in the group in which TRAIL which dosage is 400 μg/day per mouse is administrated combining with CPT-11, at the 28 th day, there are 7 tumor disappeared mice from the 10 administrated mice ( FIG. 7B ).
[0081] In HT-29 colon cancer model insensitive to TRAIL, when NGR-L-TRAIL is used lonely, even the intraperitoneal injection dosage is up to 400 μg/day per mouse, only weak anti-tumor effect can be found. However, when NGR-L-TRAIL combines with CPT-11 to treatment, the growth of tumor is inhibited significantly, and the effect is better than that of combination of TRAIL with CPT-11. When NGR-L-TRAIL which dosage is 400 μg/day combining with CPT-11 which dosage is 25 mg/kg/day, the growth inhibitory activity to tumor is best, and far better than the group in which NGR-L-TRAIL which 400 μg/day is administrated (p<0.01), and better than that of the group in which CPT-11 which dosage is 25 mg/kg/day (p<0.05), and also, is better than that of the group in which TRAIL which dosage is 400 μg/day is administrated combining CPT-11 which dosage is 25mg/kg/day (p<0.05).
[0082] Generally speaking, in the above mentioned cancer models, when combing with CPT-11, the anti-tumor activity of NGR-L-TRAIL is stronger than the effect when using NGR-L-TRAIL or CPT-11 lonely, and the effect of NGR-L-TRAIL combing with CPT-11 is better than the effect of TRAIL combining with CPT-11. When the dosage of NGR-L-TRAIL is 1/9˜1/3 and 1/5 dosage of TRAIL separately, which inhabitation effect to COLO-205 and HCT-15 tumor that is sensitive is equal to the effect of TRAIL. When NGR-L-TRAIL combines with CPT-11, which growth inhibitory activity to HT-29 tumor that is insensitive to TRAIL is better than that of same dosage of TRAIL combining CPT-11. The results show that: when combining with CPT-11, the anti-tumor activity of the tumor-targeted variant protein NGR-L-TRAIL is significantly improved compared with which using lonely, and the growth inhibitory activity to tumor is better than the combination of wild TRAIL with chemotherapeutic drugs. Furthermore, the combination expands the scope of its application. The tumor- targeted variant protein can efficiently inhibit the growth of tumors that is insensitive to TRAIL (such as HT-29 colon cancer).
[0083] The animal model experiments in vivo prove the better effect of the tumor-targeted TNF-related apoptosis-inducing ligand's variant NGR-L-TRAIL than wild TNF-related apoptosis-inducing ligand, and the variant RGF-L-TRAIL of TRAIL targeted intergrin αVβ3 and intergrin αVβ5. It indicates that, when combining with tumor-targeted peptide targeted CD13, the TNF-related apoptosis-inducing ligand can increase the anti-tumor biological activity at the level of animal tumor model. Similarly, the TNF-related apoptosis-inducing ligand's variant not only increase the effect when used lonely, but also has more significant effect when combining with chemotherapeutic drugs because the significant synergistic effect. The combination of the TNF-related apoptosis- inducing ligand's variant with CPT-11 not only can decrease the their dosage, minimize the potential systemic toxicity, but also can expand the scope of application to the tumor that is insensitive to TNF-related apoptosis-inducing ligand originally ( FIG. 8 ). The animal experiments in vivo prove that the treatment effect of the tumor-targeted TNF-related apoptosis-inducing ligand's variant is favorite than the TNF-related apoptosis-inducing ligand, even than the variant RGF-L-TRAIL of TRAIL targeted intergrin αVβ3 and intergrin αVβ5.
Embodiment 7
[0084] The Test of Drug Distribution of Recombinant Protein in Tumor Tissue
[0085] The recombinant TNF-related apoptosis-inducing ligand's variant NGR-L-TRAIL, and variant RGD-L-TRAIL is separately labeled by the kit labeled by the radioisotope 125 I. The results of the labeling experiment are that: the specific activity of 125 I-TNF-related apoptosis-inducing ligand is 7.86 μCi per one μg of protein, and the specific activity of 125 I-TNF-related apoptosis-inducing ligand's variant is 7.49 μCi per one μg of protein. After implanting the COLO-205 colon tumor, the nude mice are randomized for mild group and two variant groups when the tumor volume is up to 400 to 500 cubic millimeters. 5 time points, that are 5, 30, 60, 120 and 240 minutes separately, are set. At each time point 3 animals are selected, and 5 μCi of labeled protein is injected for each tumor-bearing nude mouse. At each time point, the tumor tissue is enulcleated by surgical operation from the mouse and weighed. The radiological dose is detected by Liquid Scintillation Counter. The abundance of labeled protein in tumor tissue is calculated by the percent of the detected radiological dose per gram of the tissue to injection radiological dose (% ID/g).
[0086] To further prove that the increase of the anti-tumor activity of the TNF-related apoptosis-inducing ligand's variant in animal model results from its enrichment into tumor tissue, and to compare the targeting capacity of NGR-L-TRAIL and RGD-L-TRAIL in tumor animal model, the distributions of the TNF-related apoptosis-inducing ligand's variant NGR-L-TRAIL and RGD-L-TRAIL labeled by isotope 125 I, and mild TRAIL in tumor tissue are detected. The TNF-related apoptosis-inducing ligand and the variant thereof labeled by the same radiological dose 125 I are injected in to COLO-205 tumor-bearing nude mice separately. 5, 30, 60, 120 minutes after the injection, tumor tissues of the mice are enulcleated by surgical operation and weighed. The radiological doses of the isotope are detected by Liquid Scintillation Counter separately. The results show that: when the TNF-related apoptosis-inducing ligand TRAIL combines with the short peptide ligand CNGRC of CD13, and the short peptide ligand ACDCRGDCFC of intergrin αVβ3 and intergrin αVβ5, the enrichment capacity of TRAIL protein target into COLO-205 tumor tissues is increased significantly and NGR-L-TRAIL can be exist and specifically enriched in tumor tissues. Just after the injection, the abundance of 125 I-RGD-L-TRAIL is approximately 2 times as much as that of 125 I-TRAIL in tumor tissue, and the abundance of 125 I-NGR-L-TRAIL is approximately 2.5 times as much as that of 125 I-TRAIL in tumor tissue, and the abundance of 125 I-NGR-L-TRAIL in COLO-205 tumor tissue is significantly higher than that of 125 I-TRAIL ( FIG. 9 ).
[0087] Because of the increase of the affinity of NGR-L-TRAIL and RGD-L-TRAIL to tumor tissues and the expanded distribution in tumor tissues, their rate to be removed in circulatory blood is slowed down greatly, so that their distributing time is prolonged. 240 minutes after the injection, it is difficult to find the distribution of TRAIL in tumor tissue, but there still is quite a few of RGD-L-TRAIL distributing in the tumor region ( FIG. 9 ), and the content of NGR-L-TRAIL in tumor tissues is twice as much as the content of RGD-L-TRAIL. The above results show that, when combining with TRAIL, the peptide CNGRC retains the biological function of the peptide CNGRC to be bound to vascular endothelial cells, and of inhibition its hyperplasia and of the inducing apoptosis. Thus, both the facts of the increase of the distribution in tumor tissues and of the anti-tumor activity detected in animal models of TNF-related apoptosis-inducing ligand's variant prove that the TNF-related apoptosis-inducing ligand's variant NGR-L-TRAIL provided by the present invention can give the TNF-related apoptosis-inducing ligand better and stronger tumor targeting captivity than TGD-L-TRAIL, and can decrease the dose of administration, and finally can improve the anti-tumor effect. It is the first to improve that the ligand of CD13, which targeting captivity is favorite than RGD ligands of intergrins that is used for early diagnosis of tumor, is a favorite probe for the diagnosis of tumor in the present invention.
Embodiment 8
[0088] Binding of the Recombinant Protein and Tumor Tissue In Vivo
[0089] TNF-related apoptosis-inducing ligand and the tumor-targeted variant NGR-L-TRAIL, RGD-L-TRAIL, Bovine Serum Albumin are labeled by green fluorescein. The nomadic fluorescein is removed by gel molecular sieve Sephadex-G25 from the labeled protein. 500 μg of protein labeled by green fluorescein is injected into the tumor-bearing nude mouse when the volume of tumor tissue is up to 400 to 500 cubic millimeters by tail vein injection. 30 minutes after the injection, tumor tissue of the mouse is enulcleated by surgical operation to prepare the single-cell suspension of the tumor cells. After washed by physiological saline for several times, 60 thousands of cells are selected to be detected by Flow Cytometer to analyze the binding of the recombinant protein to the surface of the tumor cells.
[0090] The statistical analysis of the data is carried out by the software of Statistical Package for the Social Science. All of the experiments are repeated for at least 3 times. The results of apoptosis-inducing and adhesion experiments are stood for by average standard deviation, and the volume of tumor is stood for by standard error. When p is less than 0.05, the significance difference is deemed to; and when p is less 0.01, the extremely significance difference is deemed to, marked by one or two asterisks separately.
[0091] The distribution of NGR-L-TRAIL in other tissues is similar to TRAIL, and there is no specificity enrichment in other visceral organs ( FIG. 10A , FIG. 10B ). The metabolite of NGR-L-TRAIL in vivo is eliminated from the body by kidney chiefly ( FIG. 10B ).
[0092] Thus, the increase of the distribution in the tumor region in the body of animals and the increase of the anti-tumor activity that is detected in animal models fully demonstrate that NGR-L-TRAIL designed by our molecular design is superior to RGD-L-TRAIL, and can give favorite targeting captivity to TRAIL protein and finally can increase the anti-tumor effect. | The invention belongs to the field of genetic engineering and biotechnology, and specifically discloses a design, preparation and pharmic application of a tumor-targeted TNF-related apoptosis-inducing ligand's variant. The tumor-targeted TNF-related apoptosis-inducing ligand's variant is generated by a fused protein which is consisted of the ligand of CD13, the connecting peptide and TNF-related apoptosis-inducing ligand's variant, and which is by the construction of coding gene of the variant according to the technology of genetic engineering and clone, soluble recombinant expression and ordinary separation and purification. The variant, produced by the method of preparation of the tumor-targeted TNF-related apoptosis-inducing ligand's variant, has favorable tumor-targeting characteristics and the significant enhancement of the anti-tumor effect. It is possible to reducing the required dosage of protein to the treatment effect, increasing the bioavailability, reducing the cost of treatment and overcome the potential toxic effects of the TNF-realated apoptosis-inducing ligand. Moreover, the preparation method of the tumor targeted TNF-related apoptosis-inducing ligand's variant of the present invention provides a method for producing the variant of soluble expression and high concern of polymer forms and a process of separation and purification thereof. | 2 |
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for producing a delayed version of a sequence of bits, and, more particularly, to a method and apparatus for producing a delayed version of a maximum length sequence output from a linear feedback shift register.
Linear feedback shift registers (LFSR's) are employed in a variety of applications, including generating the pseudo-random spreading codes used in code division multiple access (CDMA) transmission systems. In CDMA systems a need arises to produce a specified maximum length sequence with an arbitrary delay. For example, the receiver's linear feedback shift register must be set up to generate the same pseudo-random spreading code sequence as that of the transmitter. This is a necessary, but not sufficient, condition to enable reception of the transmitted signals. The receiver does this by using the precise transmitter time offset. Thus, an important function which the receiver must perform is to produce the specified maximum length sequence from the linear feedback shift register with an arbitrary delay.
A maximum length sequence of order m is a sequence of 2 m -1 binary digits (bits) such that the smallest continually repeating pattern within the sequence is the sequence itself. A first maximum length sequence which is delayed by an arbitrary delay value q, such that 0≦q<2 m -1, is a second maximum length sequence which is identical to the first maximum length sequence, except that the bits of the second maximum length sequence are offset by q bit positions from the corresponding bits of the first maximum length sequence.
A linear feedback shift register of m stages generates certain elements of a finite Galois field of order 2 m . (A concise summary of linear feedback shift registers is given by Beker and Piper in Cipher Systems, Wiley-Interscience, 1982.) Galois fields of order 2 m may be represented by binary polynomials expressed in terms of a polynomial argument, hereinafter denoted as "x", with modulo addition and modulo multiplication defined using a primitive polynomial as the modulus. A primitive polynomial is a polynomial which does not factor and divides x T +1, where T=2 m -1. The addition operation on a Galois field of order 2 m , denoted by `+`, is equivalent to the binary exclusive-OR operation. Multiplication by x in a Galois field of order 2 m is a modulo left-shift of the binary digits representing the polynomial multiplicand. All the 2 m -1 non-zero elements of a Galois field of order 2 m may be produced by successive powers of a particular element, usually chosen to be x. With the inclusion of the zero element, there are thus a total of 2 m elements in such a field.
FIG. 1 illustrates the prior art Galois form of a linear feedback shift register. The m stages of the LFSR are flip-flops containing the states of the m terms of the polynomial representing the current state. The zero-order term of the state a 0 is a flip-flop 14, the α m-2 term is a flip-flop 12, and the α m-1 term is a flip-flop 10. The ellipsis . . . indicates intermediate stages not shown, and it is understood that the descriptions illustrated here for the stages shown also apply to the stages not shown. The corresponding polynomial that is represented by that state is α 0 x m-1 +. . . +α m-1 x 0 . The LFSR sequence output 19 is a 0 from flip-flop 14, which is also fed to a series of weighted taps 18, 20, and 22. The weights are either 0 or 1, and represent the coefficients of a generator polynomial. For example, tap 18 is set according to the coefficient g 1 , tap 20 is set according to the coefficient g 2 , and tap 22 is set according to the coefficient g m-1 . If the generator polynomial is a primitive polynomial over the Galois field, then the output of the LFSR will be a maximum length sequence. Each bit position of the sequence output corresponds to a clock pulse, and all flip-flops receive input clock pulses simultaneously on a common line 17. Each flip-flop stores the value input therein at each successive clock pulse and presents the value stored therein as an output to the next flip-flop. Between pairs of flip-flops are modulo 2 adders 16 which combine the weighted sequence output of the LFSR with the output from the previous flip-flop of the pair. Each successive bit position of a sequence output from a linear feedback shift register corresponds to a successive state of the linear feedback shift register, which in turn corresponds to a successive clock pulse by which the state of the linear feedback shift register is advanced. The present application uses the term "clock time" to denote the integer which represents the number of a particular clock pulse. Clock time is used to reference the state of a linear feedback shift register as well as a bit position within a particular sequence.
The state of a linear feedback shift register at a clock time k is specified by the states of the flip-flops α 0 , α 1 , . . . , α m-2 , α m-1 , at clock time k. These states may be preset at state inputs 11, 13, and 15. The state may be written as a column vector:
a=[α.sub.0 α.sub.1 . . . α.sub.m-2 α.sub.m-1 ].sup.T(1)
It is noted that mathematically, a polynomial may be represented as a vector, and for computational purposes in this field of art, the two forms are often interchanged. The elements of a vector are generally referred to as "components," whereas the equivalent elements in the polynomial are the "coefficients" of the powers of the variable used in the polynomial. Therefore, the present application uses the terms "component" and "coefficient" to refer equivalently to the same computational entity, whether in respect to a vector or to a polynomial.
The sequence of bits in the sequence output from a linear feedback shift register is determined by the settings of the weighted taps and the initial state. The trivial initial state of a=0 will generate the trivial sequence of all zeros (a zero output with a period of one). Different non-trivial initial states will generate the same sequence of bits, although the outputs for different non-trivial initial states will be delayed by different amounts. The trivial sequence is of no interest, and therefore the present application hereinafter uses the term "initial state" to denote one of the 2 m -1 non-trivial initial states. The sequence of bits output from a linear feedback shift register has the maximum period of 2 m -1 if the weighted taps correspond to the coefficients of a primitive polynomial. Primitive polynomials always have g 0 =g m =1, and therefore the weighted taps corresponding to the respective coefficients are simply direct connections. A sequence of maximum period is referred to as a maximum length sequence, or an m-sequence. For a linear feedback shift register whose weighted taps are set up to generate an m-sequence, the 2 m -1 different initial states will generate the m-sequence with every one of the 2 m -1 possible delays.
If the state of a linear feedback shift register at a clock time l is denoted by a.sup.(l), then the following recursion holds:
a.sup.(l+1) =Ma.sup.(l) (2)
where M is the transition matrix ##EQU1##
One way to produce a delayed version of a sequence is to use a linear feedback shift register with a mask that multiplies the cell values of the linear feedback shift register according to a plurality of inputs corresponding to the stages of the linear feedback shift register. That is, a linear feedback shift register of m stages will utilize a mask with m inputs. FIG. 2 illustrates the prior art use of such a linear feedback shift register with a mask, which is implemented by a plurality of AND gates 26. Each of the AND gates 26 has an input from each output of the m flip-flops which make up the LFSR. The other inputs of AND gates 26 are the mask coefficients b m-1 , b m-2 , . . . b 1 , and b 0 . The outputs of AND gates 26 are fed into a binary adder 28, whose output is c. The output c is the same as the sequence output of the LFSR except that it is delayed by a certain amount. For example, a simple but importance case is b.sup.(0) =[10 . . . 0 0] T (b 0 =1 and b 1 =b 2 = . . . =b m-2 =b -1 =0). For this case, the output c will be the same as α 0 ; that is, there will be no delay. The problem of producing an arbitrary delay, therefore, becomes that of selecting the mask components b 0 , b 1 , b 2 , . . . , b m-2 , and b m-1 which will produce the desired arbitrary delay.
For conceptual simplicity in developing the mathematical formalism, the present application uses negative values of delay. A negative delay is an advance, so the problem is transformed into finding the mask b.sup.(q) which yields the sequence advanced by q clock pulses. Since the sequence is periodic, searching for a time offset can be done either by a delay or by an advance. If the sequence length is 2 m -1 (such as for a maximum length sequence), an advance of q and a delay of 2 m -1-q produce the same result. The present application uses the term "offset" to denote an integer number of bit positions by which one sequence is delayed with respect to another otherwise identical sequence, but without regard to which of the two sequences has been delayed. Thus, an advance of q bit positions and a delay of q bit positions are both offsets of q bit positions.
Starting from the state a 0 , the linear feedback shift register state advanced by q clock pulses from a 0 is a.sup.(q), which can be found by iterating Equation (2), and using the matrix of Equation (3):
a.sup.(q) =M.sup.q a.sup.(0) (4)
Because the output is from a 0 , the advanced output will be given by
α.sub.0.sup.(q) [10 . . . 00]M.sup.q a.sup.(0) (5)
Hence, the mask b.sup.(q) for the sequence advanced by q is obtained by: ##EQU2##
The method of Equation (6), that of matrix exponentiation, is the current prior art method of obtaining the mask b.sup.(q) for an arbitrary clock time advance of q clock pulses. That is, to obtain the mask for an arbitrary advance of q clock pulses, it is sufficient to raise the transpose matrix M T to the power q, because the desired mask b.sup.(q) is simply the first column of (M T ) q . Toward this end, certain improvements have been made in implementing matrix exponentiation. For example, U.S. Pat. No. 5,532,695 discloses a circuit arrangement for fast matrix multiplication. Nevertheless, matrix multiplication still involves considerable computation. When this is compounded by the need to raise a matrix to a power, the computation burden is correspondingly increased, even for efficient algorithms, and is a barrier to increased performance.
There is thus a widely recognized need for, and it would be highly advantageous to have, a method which efficiently produces a version of a maximum length sequence output of a linear feedback shift register with an arbitrary delay. This goal is met by the present invention.
SUMMARY OF THE INVENTION
According to the present invention there is provided a method and apparatus for efficiently obtaining a delayed version of a maximum length sequence from a linear feedback shift register. The efficiency is obtained by avoiding the need for matrix exponentiation, and by performing a polynomial exponentiation instead. A polynomial exponentiation is equivalent to a vector exponentiation, and it can readily be seen that the computational complexity is less than that of matrix exponentiation. For an m-stage LFSR, the matrix has m 2 elements and therefore requires a computational effort proportional to m 2 , whereas the polynomial has only m elements and therefore requires computational effort proportional to m. Such a computation is especially well-suited to the polynomials of Galois fields of order 2 m , particularly because the circuitry to implement algebraic operations on the elements of Galois fields of order 2 m is very simple. Furthermore, methods of fast exponentiation, including the method of exponentiation by repeated squaring and multiplication, are well-known in the art.
Therefore, according to the present invention there is provided a method for producing an offset of q bit positions in a sequence of bits output from a linear feedback shift register having m stages and a plurality of weighted taps, the weights of the weighted taps being determined by a generator polynomial having a polynomial argument of x, the method including the steps of: (a) providing a linear feedback shift register with a mask, the mask having inputs; (b) calculating the coefficients of x raised to a power modulo the generator polynomial; and (c) inputting the coefficients into the inputs.
In order to derive the steps of the method, it is necessary to transform the problem to the sequence output from a conjugate linear feedback shift register in the Fibonacci form. From that perspective, the polynomial exponentiation and multiplication operations are more readily apparent. Polynomial exponentiation is performed by repeated squaring and advancing of the linear feedback shift register, as is well-known in the art. Efficient squaring of a polynomial in the Galois field of order 2 m may be done by a modified Galois form linear feedback shift register hereinafter referred to in the present application as a "division circuit." Combinations of squaring by the division circuit and advancing of a linear feedback shift register perform the polynomial exponentiation required to generate the mask that produces the desired delay of the maximum length sequence.
Therefore, according to the present invention there is also provided an improved linear feedback shift register for producing an offset in a sequence of bits, the linear feedback shift register having a plurality of stages, a plurality of modulo 2 dders, and a plurality of weighted taps, the improvement including: (a) a mask having inputs; and (b) a mechanism for calculating the inputs to the mask, wherein the mechanism is operative to calculating a power of a polynomial.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 shows the Galois form linear feedback shift register.
FIG. 2 shows the use of a mask to produce a delayed output from a Galois form linear feedback shift register.
FIG. 3 shows the Fibonacci form linear feedback shift register, or conjugate linear feedback shift register.
FIG. 4 shows a division circuit for squaring a polynomial.
FIG. 5 shows a block diagram how the division circuit of FIG. 4 could be operated in order to obtain the mask
FIG. 6 shows a block diagram for implementing the squaring operation.
FIG. 7 shows a block diagram illustrating another implementation of the squaring operation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is of a method and apparatus which can be used to generate an arbitrarily delayed version of a sequence of bits output from a linear feedback shift register.
The principles and operation of the method and apparatus according to the present invention may be better understood with reference to the drawings and the accompanying description.
FIG. 3 illustrates the prior art Fibonacci form of a linear feedback shift register. This form is said to be "conjugate" to the Galois form illustrated in FIG. 1, and is also referred to a conjugate linear feedback shift register (CLFSR). As in the Galois form, the m stages of the CLFSR are flip-flops containing the states of the m terms representing the current state. The zero-order term α 0 is a flip-flop 44, the α m-2 term is a flip-flop 42, and the α m-1 term, which provides the sequence output 49 of the CLFSR, is a flip-flop 40. The ellipsis . . . indicates intermediate stages not shown, and it is understood that the descriptions illustrated here for the stages shown also apply to the stages not shown. The outputs of the flip-flops are fed into weighted taps 52, 50, and 48, respectively as well as to the subsequent flip-flops. The weights of these weighted taps are either 0 or 1, and represent the coefficients of a primitive polynomial over the Galois field. For example, tap 48 is set according to the coefficient g 1 , tap 50 is set according to the coefficient g 2 , and tap 52 is set according to the coefficient g m-1 . All flip-flops receive input clock pulses simultaneously on a common line 47, and each flip-flop stores the value input therein at each successive clock pulse and presents its stored value as its output, which is the input to the next flip-flop. The states of the flip-flops may be set using state inputs 41, 43, and 45.
As is well-known in the art, Galois form and the Fibonacci form produce identical sequences if their tap weights are the same. For a given initial state, however, the sequences these two forms produce are not necessarily synchronized, but may have a respective delay. The Galois form is more commonly used than the Fibonacci form, but the Fibonacci form is of theoretical importance, and is utilized as an intermediate step in the derivation of the present invention.
The CLFSR satisfies the following recursion relationship:
a.sup.(l+1) =M.sup.T a.sup.(l) (7)
where M is the matrix of Equation (3). Note that it is the transpose of M which is applicable to the Fibonacci form CLFSR: ##EQU3##
Thus, recalling Equation (6), the desired mask b.sup.(q) is obtained by first initializing the CLFSR with a.sup.(0) =[10 . . . 00] T and then advancing the CLFSR by q clock pulses. The mask b.sup.(q) is then the state of the CLFSR at that time. That is,
b.sub.j.sup.(q)=α.sub.m-1.sup.(q+m-1-j) j=0,1, . . . , m-(9)
To efficiently advance the CLFSR use is made of the fact that the sequence output from the Galois form LFSR is identical to the sequence output from the Fibonacci CLFSR, with a possible delay. To avoid the delay, it is possible to set the initial state of the Galois form LFSR to a.sup.(0) =[00 . . . 01] T and thereby obtain the result that the sequence produced by the LFSR (initialized with [00 . . . 01] T ) at a 0 is identical to the sequence produced by the CLFSR (initialized with [10 . . . 00] T ) at a m-1 . Hence
b.sub.j.sup.(q)=α.sub.0.sup.(q+m-1-j) j=0,1, . . . ,m-1.(10)
Thus, the problem of determining the mask b.sup.(q) from Equation (10) is reduced to the problem of efficiently calculating the value of x raised to the power of q modulo the generator polynomial, x q mod g(x), where g(x) is the generator polynomial used for the LFSR:
g(x)=1+g.sub.1 x+g.sub.2 x.sup.2 +. . . g.sub.m-1 x.sup.m-1(11)
Once x q mod g(x) has been obtained, the LFSR is advanced by m-1 additional steps to obtain b.sup.(q) according to Equation (10).
It is noted at this point that the CLFSR is useful only in the foregoing theoretical derivation of determining an efficient way of calculating the mask b.sup.(q). The CLFSR is not needed for any computations, and hereinafter will not be utilized.
As is well-known in the art, exponentiation can be performed by repeated squaring and multiplication. To calculate x q , first obtain the binary representation of q:
q=q.sub.0 2.sup.1-l +q.sub.1 2.sup.m12 +. . . +q.sub.1.1 where 1≦m and q.sub.0 =1 (12)
Then, ##EQU4##
A "next state operation" N implements the multiplication of a polynomial by x modulo the generator polynomial as in Equation (13):
N(f)=x·f modg(x) (14)
where f is the polynomial represented by the current state of the LFSR. This simply advances the LFSR by one clock pulse.
A "squared value operation" S calculates the square of a polynomial modulo the generator polynomial as in Equation (13):
S(f)=f.sup.2 mod g(x) (15)
where f is the polynomial represented by the current state of the LFSR. To perform an efficient squared value operation on f=f 0 x m-1 +f 1 x m-2 +. . . +f m-1 x 0 , it is noted that:
f.sup.2 =f.sub.0 x.sup.2m-2 +f.sub.1 x.sup.2m-4 +. . . +f.sub.m-1 x.sup.0(16)
The right-hand side of Equation (16) can be easily seen, since the cross-terms which result from the squaring of f occur in pairs, and the properties of addition in Galois fields of order 2 m are such that these pairs of cross-terms will cancel, leaving only the terms in x 2m-2 , x 2m-4 , and so forth. Furthermore, the properties of multiplication in Galois fields of order 2 m are such that (f i ) 2 =f i for all the coefficients of f It is noted that the right-hand side of Equation (16) has only even powers of x. Therefore, to calculate S(f), it is sufficient to input an expanded sequence input f m-1 , 0, f m-2 , 0, . . . f 1 , 0, f 0 into a division circuit, which is a linear feedback shift register that has been modified according to the present invention.
FIG. 4 illustrates a division circuit according to the present invention for the purpose of calculating the square of an arbitrary polynomial, that is, a polynomial with arbitrary coefficients. It is similar in structure to the Galois form of the linear feedback shift register as shown in FIG. 1, but it is employed differently and innovates a sequence input 78 instead of a sequence output as in the LFSR and CLFSR. The m stages of the division circuit are flip-flops containing the states of the m terms of the polynomial representing the temporary division result. The zero-order term α 0 is a flip-flop 64, the α m-2 term is a flip-flop 62, and the α m-1 term is a flip-flop 60. The ellipsis . . . indicates intermediate stages not shown, and it is understood that the descriptions illustrated here for the stages shown also apply to the stages not shown. Sequence input 78 is put into a modulo 2 adder 76 which adds the input to the output from flip-flop 64, which is also fed to a series of weighted taps 68, 70, and 72. The weights are either 0 or 1, and represent the coefficients of the same primitive polynomial over the Galois field that is used to generate the maximum length sequence with the linear feedback shift register as shown in FIG. 1. For example, tap 68 is set according to the coefficient g 1 , tap 70 is set according to the coefficient g 2 , and tap 72 is set according to the coefficient g m-1 . All flip-flops receive input clock pulses simultaneously on a common line 67, and each flip-flop stores the value input therein at each successive clock pulse and presents its stored value as its output. Between pairs of flip-flops are modulo 2 adders 66 which combine the weighted output of flip-flop 64 with the output from the previous flip-flop of the pair. Each uccessive state of the division circuit corresponds to a successive clock pulse by which the state of the division circuit is advanced. The states of the flip-flops may be set by putting the proper signals on state inputs 81, 83, and 85. Further features of the division circuit include state outputs 61, 63, and 65 for reading the state of the polynomial, and a clear state line 69 common to all the flip-flops and which is provided for resetting the state of the linear feedback shift register by resetting or clearing each flip-flop to zero (0).
FIG. 5 shows how the division circuit illustrated in FIG. 4 should be operated in order to obtain the mask components. First, the LFSR taps {g i } which correspond to elements 68, 70, intermediate stages, and 72 in FIG. 4 and the desired delay q are inputted (box 90). The initial state is set so that the a m-1 term is 1 while the other terms are 0 (box 92). This initial state avoids a delay between sequence outputs from a CLFSR and a LFSR as explained above. Note that the terms of a state are represented in FIG. 4 by flip flops 60, 62, intermediate stages, and 64. The delay q is expanded into its binary representation q=q 0 2 1-1 +q 1 2 m12 +. . . +q 1-1 where 1≦m and q 0 =1 (box 94). In order to obtain a result equivalent to equation 13, the operations represented by boxes 96, 98 and 100 are performed 1--1 times. First the current LFSR state is squared (box 96). If the next q coefficient (q 1 ) is 1 (box 98), x qi =x, a next state operation must be performed (box 100) prior to subsequent squaring. The next state operation is accomplished by inputting a zero at the sequence input 78 of FIG. 4. Otherwise, x qi =x 0 1, and an additional squaring (box 96) can be performed without any intermediate operations. The assignment is performed m-1 times. After each assignment, the division circuit of FIG. 4 is advanced by inputting a 0 at the sequence input (78 in FIG. 4, box 104 in FIG. 5). Once all the mask terms are obtained (box 106 in FIG. 5), the mask terms are inputted to produce the desired delay.
The squaring function (box 96 of FIG. 5) may be implemented as per FIG. 6. The current LFSR state is read from state outputs 61, 63, and 65 (in FIG. 4) as per box 108. The division circuit of FIG. 4 is cleared by asserting a signal on clear state line 69 (box 110). The expanded sequence a m-1 , 0, a m-2 , 0, . . . , a 1 , 0, a 0 is inputted into sequence input 78 with a 0 being inputted first (box 112). The expanded sequence input of a polynomial is a sequence which has twice as many bits as the polynomial and which alternates the coefficients of the polynomial with 0. With each bit of the sequence, a clock pulse is put into line 67. When the entire expanded sequence input has been input, the squared values are read from state outputs 61, 63, and 65 (box 114).
In another embodiment, shown in FIG. 7. the LFSR state is initialized to a 0 , 0, a 1 , 0, . . . a m/2-2 0, am /2-1 , 0 (box 118) and the sequence a m-1 , 0, a m-2 , 0, . . . , a m/2 is inputted into sequence input 78 with a m/2 inputted first into box 120.
In an embodiment of the present invention, the division circuit is first cleared by asserting a signal on clear state line 69, and then putting the expanded sequence input f m-1 , 0, f m-2 , 0, . . . , f 1 , 0, f 0 into sequence input 78. The expanded sequence input of a polynomial is a sequence which has twice as many bits as the polynomial and which alternates the coefficients of the polynomial with 0. With each bit of the sequence, a clock pulse is put onto line 67. When the entire expanded sequence input has been input, the value S(f) is read from state outputs 61, 63, those of the intermediate stages not shown, and 65. In another embodiment, the state of the division circuit can be initialized to the values of 0, f m/2-1 , 0, f m/2-2 , 0, . . . , f 1 , 0, f 0 and then input the sequence f m-1 , 0, f m-2 , 0, . . . , fm m/2 . (For notational simplicity, it is assumed that m is even here.)
Once x q mod g(x) has been obtained, it is necessary to apply m-1 additional next state operations N(f) to obtain the mask b.sup.(q) according to Equation (10). When the mask b.sup.(q) has been obtained, the mask components are input into the delayed output linear feedback shift register, as illustrated in FIG. 2. The resulting sequence has the desired delay.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that variations, modifications and other applications of the invention may be made. | Method and apparatus for efficiently producing a delayed version of a maximum length sequence output from a linear feedback shift register. Polynomial (vector) exponentiation is performed instead of matrix exponentiation to calculate the mask coefficients which yield the delayed sequence from the linear feedback shift register. Polynomial (vector) operations are much simpler and faster than the corresponding matrix operations and require substantially less circuitry and computational effort. Modulo exponentiation of polynomials is done by repeated squaring and shifting, and a division circuit built on a linear feedback shift register is provided to perform an efficient modulo squaring of polynomials. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 13/074,098 filed Mar. 29, 2011, the entire disclosure of which is hereby explicitly incorporated by reference herein.
BACKGROUND
1. Field of Invention
The present invention relates to a warehouse or structure that mass freezes and stores bulk foods and other products, and in particular to racking and chilling structures in the warehouse.
2. Description of Related Art
Two-stage freezer warehouses are known in which large pallets of items including meats, fruit, vegetables, prepared foods, and the like are frozen in blast rooms of a warehouse and then are moved to a storage part of the warehouse to be maintained at a frozen temperature until their removal. Such two-stage freezer warehouses require separate blast and storage rooms that encompass a relatively large amount of space.
U.S. patent application Ser. No. 12/877,392 entitled “Rack Aisle Freezing System for Palletized Product”, filed on Sep. 8, 2010, relates to an improved system for freezing food products. Shown in FIG. 1 is a large warehouse 2 that is used to freeze and maintain perishable foods or like products. Large pallets of items, including meats, fruits, vegetables, prepared foods, and the like, are sent to warehouse 2 to be frozen employing a system whereby the palletized foods are frozen on storage racks.
FIG. 2 shows a top view of the interior of warehouse 2 , in which rows of palleted product are shown such that pallets 4 abut chambers 6 . As shown in FIG. 3 , rows of racking 14 are positioned between aisles 10 and chambers 6 . Each chamber 6 is enclosed by a pair of end walls 15 and top panel 17 . Cold air produced in warehouse 2 is drawn through spacers 20 ( FIGS. 5 and 6 ) separating rows of cases 22 of product on pallets 4 , creating a palletized product stack which is disposed and sealed against the exterior of racking 14 ( FIG. 3 ) via forklifts 18 .
Chillers 8 ( FIG. 2 ) provided in the interior of warehouse 2 produce the cold air and maintain the temperature of ambient air within the warehouse space at a level below freezing. A plurality of racking structures 14 ( FIGS. 3 and 4 ) each define a plurality of adjacent air flow chambers 6 ( FIGS. 2 and 4 ) having air intake openings on opposite sides thereof and a plurality of air outlets having air moving devices, such as exhaust fans 12 , on top panels 17 , which causes freezing air to be drawn into chambers 6 through intake openings and to then exhaust into the warehouse space. The plurality of airflow chambers 6 are each defined by a pair of end walls 15 and top wall 17 having one or more air outlets and exhaust fans associated therewith ( FIG. 3 ). Pallets 4 on pallet guides are pressed against the intake openings such that a seal is formed between the pallets and the intake openings via side periphery seals, a bottom periphery seal, and atop periphery seal that is selectively adjustable via a vertically manually adjustable bracket to which the top periphery seal attaches. The seals together define each intake opening. Freezing air is drawn through air pathways 16 ( FIGS. 2, 4, and 5 ) within the palletized product in a direction towards chamber 6 to thereby quickly freeze the product. As shown in FIG. 5 , spacers 20 may be placed between rows of cases 22 of product to provide air pathways 24 through which air flow can enter chamber 6 .
While the top periphery seal may be adjusted via the corresponding bracket, a manual adjustment is required before product stacks of varying heights my be disposed against the intake openings such that a seal is formed between the stacks and openings. What is desired is an improvement over the foregoing.
SUMMARY
The present disclosure provides an automatically adjustable swing seal that for the rack-aisle freezing and chilling system described above extends, for example, from the top horizontal frame member of a racking structure and defines an intake opening along with side seals and a bottom seal. The swing seal is positioned at a height such that a product stack having a top edge positioned at any point along the face of the swing seal creates a seal between the intake opening and the stack via the swing seal, the side seals, and the bottom seal. Thus, stacks of varying heights may automatically be accommodated. Further, the bottom edge of the swing seal may be beveled, such that if a product a stack is not evenly stacked, a portion of the uneven stacking will not catch against the swing seal when the stack is pulled away from the opening.
In one form thereof, the present disclosure provides an installation for chilling or freezing and cold storage of product stacks of palletized product, including a cold storage warehouse space, at least one chiller in the warehouse space that produces chilled or freezing air and maintains the temperature of ambient air in the warehouse space at chilled or below freezing, at least one air flow chamber including opposite walls, a plurality of air intake openings in at least one wall of the walls, and at least one air outlet having an associated air moving device for causing chilled or freezing air to be drawn into the chamber through the air intake openings and exhausted into the warehouse space through the air outlet, and swing seals disposed over respective air intake openings, each swing seal hingedly connected to the one wall via a hinge defining a horizontal axis about which the swing seal rotates. When stacks of product to be chilled or frozen are disposed in sealing engagement with the air intake openings against the swing seals, a top edge of each engaged product stack is disposed against a front panel of the swine seal to rotate the swing seal inward about said horizontal axis of the hinge such that the swing seal and peripheral walls defining the air intake opening create a seal between the engaged product stack and the air intake opening, and chilled or freezing air is drawn through the product stack to thereby quickly freeze the product.
In another form thereof, the present disclosure provides an installation for chilling or freezing and cold storage of palletized product, including a cold storage warehouse space, at least one chiller in the warehouse space that produces chilled or freezing air and maintains the temperature of ambient air in the warehouse space at chilled or below freezing, at least one air flow chamber including opposite walls, a plurality of air intake openings in at least one wall of the walls, and at least one air outlet having an associated air moving device for causing chilled or freezing air to be drawn into the chamber through the intake openings and exhausted into the warehouse space through the air outlet, and swing seals disposed over respective air intake openings, the swing seals extending forwardly of their respective air intake openings and being yieldably movable rearwardly toward the interior of the chamber. When product stacks to be frozen or chilled are disposed in sealing engagement with the air intake openings against the swing seals, the swing seals are pushed inwardly such that the swing seal and peripheral walls defining the air intake opening create a seal between the engaged product stack and the air intake opening, and chilled or freezing air is drawn through the product stack to thereby quickly freeze the product.
In yet another form thereof, the present disclosure provides an installation for chilling or freezing and cold storage of stacks of palletized product, the installation including a cold warehouse space cooled by a chiller and a chamber having a plurality of air intake openings in a wall thereof, a method for chilling or freezing the stacks of palletized product, including providing a swing seal over each of a plurality of intake openings, the seals extending forwardly of the respective openings and being yieldably movable rearwardly toward an interior of the chamber; moving a stack of palletized product against the periphery of one of the openings thereby contacting the respective swine seal and pushing the swing seal rearwardly such that the product stack is scaled against the periphery of the opening and the swing seal; and drawing chilled or freezing air through the product stack into the chamber and out of the chamber to thereby chill or freeze the product stack.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following descriptions of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a warehouse incorporating a freezing system in accordance with the present disclosure;
FIG. 2 is a diagrammatic top view of a freezer warehouse incorporating the system of the present disclosure;
FIG. 3 is a perspective view of the interior of the freezer warehouse;
FIG. 4 is a perspective end view of two rows of racking;
FIG. 5 is a diagrammatic perspective view showing the flow of chilling air through the palletized product;
FIG. 6 shows loading of the palletized product into the racks;
FIG. 7 shows the palletized product loaded into the racks and disposed against a swing seal of the racking;
FIG. 8 is an enlarged fragmentary view showing the palletized product disposed against the swing seal of FIG. 7 ;
FIG. 9 is a perspective view of the racking structure with the palletized product disposed against the swing seal of FIG. 7 as seen from the interior air chamber;
FIG. 10 shows loading of palletized product of an alternative height into the racks;
FIG. 11 shows the palletized product of FIG. 10 loaded into the racks and disposed against a swing seal of the racking;
FIG. 12 is a fragmentary view showing the palletized product disposed against the swing seal of FIG. 11 ;
FIG. 13 is a perspective view of the racking structure with the palletized product of FIG. 10 disposed against the swing seal of FIG. 11 as seen from the interior air chamber;
FIG. 14 shows palletized product of an another alternative height loaded into the racks and disposed against a swing seal of the racking, the swing seat disposed beneath a filler panel that seals a portion of an opening of the racking;
FIG. 15 is a perspective view of the racking structure with the palletized product of FIG. 14 disposed against the swing seal of FIG. 14 as seen from the interior air chamber;
FIG. 16 is a perspective view of a portion of the racking structure accommodating twenty-four pallets on each side thereof; and
FIG. 17 is an enlarged perspective view showing the support for the swing seal.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate exemplary embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the disclosure in any manner.
DETAILED DESCRIPTION
An improved sealing system for an installation and method for chilling or freezing and cold storage of palletized product is disclosed herein. A chiller 8 provided in the interior of a cold storage warehouse 2 is used to maintain the temperature of ambient air within the space of the warehouse at a low level such as below freezing. A plurality of racking structures 14 each define a plurality of air flow chambers 6 each having walls with air intake openings on opposite sides thereof and an air outlet and fan 12 to enable freezing air to be drawn into the chamber through intake openings and exhausting into the warehouse space.
As further described below, palletized product stacks 52 on pallet guides 56 are pressed against the intake openings 54 such that a seal is formed between the palletized product stacks and the intake openings via side periphery seals, a bottom periphery seal, and an automatically adjustable top periphery swing seal, the seals together defining each intake opening 54 . Chilling or freezing air is drawn through air pathways within the palletized product in a direction towards the chamber to thereby quickly freeze the product, which may then advantageously be stored on the same rack on which it is frozen. Referring to FIG. 6 , racking structure 14 includes wall 30 , which is one of a pair of walls 30 defining the exterior of racking structure 14 . End walls 15 are disposed between the pair of walls 30 on opposite ends of racking structure 14 . End walls 15 , walls 30 , and top panels 17 having exhaust fans 12 define interior chambers 6 . Referring to FIG. 9 , chambers 6 may include posts 32 of racking structure 14 to provide stabilizing support to the structure.
Walls 30 are formed by interconnected vertical and horizontal steel frame members which may define a plurality of openings. Referring to FIG. 6 , each wall 30 of racking structure 14 includes bottom horizontal frame member 34 forming a lower seal, vertical frame members 36 that form a pair of side periphery seals 36 , and top horizontal frame member 38 . Frame members 34 , 36 , and 38 are preferably made of steel having flat faces but elastomeric material could be fastened to the front faces if desired. When product stack 52 is not disposed against wall 30 , as shown in FIG. 6 , swing seals 40 (described below), frame members/seals 34 and bottom horizontal frame member 34 define a series of intake openings 54 spaced along wall 30 of racking structure 14 .
Support guides 56 assist to position product stacks 52 within separate bays along racking structure 14 and against individual bay intake openings 54 of wall 30 . The product stacks described herein may be loaded along the empty bays of first row R 1 and/or second row R 2 . Additional rows above the first and second rows for racking structure 14 are within the scope of this disclosure and may additionally include bays into which product stacks may be positioned and disposed against respective intake openings. Product stacks are positioned against empty bays having bay intake openings other either side of racking structure 14 , such that each intake opening of racking structure 14 is covered by a product stack. Filler panels (not shown) are utilized to cover any intake openings against which a product stack is not disposed to create and maintain a sufficient negative pressure environment within internal chamber 6 .
A product stack 52 may be disposed against an intake opening 54 of a wall 30 and pressed against a front panel 47 of a swing seal 40 , as described below, at a level corresponding to the height of the product stack, such that product stacks of varying heights may be utilized with the swing seal described herein without requiring a manual adjustment of the swing seal for such varying product stacks. As further described below, the product stack 52 presses against and rotates the swing seal 40 inwardly towards chamber 6 until the product stack abuts the frame members 34 , 36 of the wall and a seal is created between the product stack and the intake opening.
Swing seal 40 is disposed below top horizontal frame member 38 of wall 30 . The swing seal may be made of a steel sheet, although other materials such as elastomeric materials may be used in desired. Swing seal 40 includes top panel 42 , a pair of side panels 44 and bottom panel 45 , which forms beveled bottom edge 46 . Top panel 42 , side panels 44 , and bottom panel 45 of swing seal 40 are disposed around the periphery of front panel 47 . Interior face 50 ( FIG. 9 ) of front panel 47 faces towards the direction of chamber 6 and exterior face 48 ( FIG. 6 ) of front panel 47 faces toward the product stack to be loaded. Further, side panels 44 define a thickness. When swing seal 40 is in an at rest position such that a product stack is not disposed against swing seal 40 , face 48 of front panel 47 protrudes forwardly from wall 30 at a distance corresponding to or less than the thickness of side panels 44 .
Referring to FIG. 7 , when product stack 52 is disposed against intake opening 54 of wall 30 , swing seal 40 yieldably moves by pivoting rearwardly towards an interior of chamber 6 via rotating about a horizontal axis from a rest position to a seal position. Alternative designs of the swing seal may yieldably move rearwardly towards the interior of chamber 6 along a horizontal plane and, for example, against a spring biased three. In the seal position, as further described below, swing seal 40 , the pair of side periphery seals 36 , and bottom horizontal frame member 34 defining the lower seal create the seal between product stack 52 and intake opening 54 .
As mentioned above, the product stacks may vary in height, as shown by the different product stacks of FIGS. 6 and 10 . For example, to cooperate with the swing seal of the present disclosure, the product stack may have a height ranging from a first height measured from floor 60 to just above bottom panel 45 of swing seal 40 to a second height measured from floor 60 to near the top portion of exterior face 48 of swing seal 40 that is at brackets 62 supporting swing seal 40 , as discussed further below.
The side panels 44 of swing seal 40 are attached to vertical frame members 36 of wall 30 via a pair of L-shaped brackets 62 such that swing seal 40 is rotatable about a horizontal axis, as described further below. Each bracket 62 includes legs 64 and 68 . Leg 64 is attached to an upper portion of frame member 36 via a fastener, such as a bolt, that extends through aperture 66 of leg 64 . Leg 68 is attached to an upper portion of side panel 44 of swing seal 40 . Side panels 44 each include a rod aperture for receipt of rod 72 . A hinge such as rod 72 extends through the pair of L-shaped brackets 52 and side panels 44 of swing seal 40 such that swing seal 40 can rotate about a horizontal pivot axis defined by rod 72 . Particularly, rod 72 extends through the rod apertures of swing seal 40 and apertures 70 of legs 68 of brackets 62 on either side of swing seal 40 and is retained in place by means of a pair of locking collars 73 fastened to rod 72 by set screws (not shown) as shown in FIG. 17 . As rod 72 defines the horizontal axis, swing seal 40 may rotate about the horizontal axis inwards towards chamber 6 .
Referring to FIG. 7 , as product stack 52 is placed or disposed against opening 54 as described above, a top corner of product stack 52 is pressed against face 48 of swing seal 40 ( FIG. 8 ) to move swing seal 40 from the rest position to the seal position. Referring to FIG. 8 , swing seal 40 is rotated about a horizontal axis of rod 72 ( FIG. 9 ) until product stack 52 abuts side periphery seals 36 and lower seal 34 of wall 30 , at which point swing seal 40 is in the seal position. In the seal position, the area of exterior face 48 of swing seal 40 seals against the top edge 84 of product stack 52 . Exterior face 48 along with side panels 44 of swing seal 40 and seals 36 and 34 restrict the passage of air to chamber 6 outside of air being directed through spacers between cases on the product stack 52 , as described below.
Referring back to FIG. 7 , chilled air is drawn into chamber 6 via product stack 52 . Product stack 52 includes cases 22 positioned on pallet 4 . Cases 22 are separated by spacers 20 such that, when product stack 52 is placed or disposed against wall 30 , air is drawn through spacers 20 ( FIG. 5 ), and/or through openings in the product boxes 22 , through intake opening 54 ( FIG. 6 ) into chamber 6 and exhausted through chamber 6 via exhaust openings such as fans 12 within top panel 17 . The air drawn through spacers 20 is chilled sub-freezing air circulated by chillers 8 ( FIG. 2 ). The chilled air is capable of freezing product of product stack 52 when drawn through spacers 20 and maintaining the product at the frozen temperature.
FIGS. 10-13 show the method described above of positioning a product stack against intake opening 54 with product stack 76 having an alternative height that is higher than product stack 52 shown in FIGS. 6-9 . Referring to FIG. 11 , as product stack 76 is placed or disposed against wall 30 as described above, a top edge 84 of product stack 76 presses against face 48 of swing seal 40 . Swing seal 40 is then rotated about a horizontal axis defined by rod 72 inwards towards chamber 6 to a sealed position, as described above ( FIG. 13 ).
Referring to FIGS. 14-15 , a product stack may be positioned at a level below bottom panel 45 of swing seal 40 . In such situations, as shown in FIG. 14 , filler panel 80 is attached below top horizontal frame member 38 of wall 30 such that it is disposed between top horizontal frame member 38 of wall 30 and top panel 42 of swing seal 40 to restrict any undesired passage of air into chamber 6 . Brackets 62 are attached to side periphery seals 36 below filler panel 80 , and swing seal 40 is attached to wall 30 via brackets 62 , in the manner described above. Product stack 82 of FIGS. 14 and 15 is then at a height such that a top edge 84 of product stack 82 may interact with swing seal 40 to rotate swing seal 40 inwards towards chamber 6 ( FIG. 15 ), as described above, creating a seal between product stack 82 and the intake opening.
Further, in the described embodiments, bottom panel 45 of swing seal 40 forms an obtuse angle with front panel 47 to form beveled bottom edge 46 . The beveled edge 46 reduces the chance that the lower edge of the swing seal 40 catches onto a product stack when the stack is being pulled back from the intake opening, or being positioned against the intake opening. Beveled bottom edge 46 prevents a product stack from getting caught or hung up onto the bottom panel of the swing seal when the product stack is being pulled back from intake opening 54 .
Further, if product stack 76 has a height such that top edge 84 is at a height level with beveled bottom edge 46 of swing seal 40 , top edge 84 can seal against beveled bottom edge 46 . This allows for a greater sealable range based on product stack height than if the bottom edge were perpendicular to front panel 47 .
While this invention has been described as having exemplary designs, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | An automatically adjustable swing seal for a rack-aisle freezing and chilling system extends, for example, from the top horizontal frame member of a racking structure and defines an intake opening along with side seals and a bottom seal. The swing seal is positioned at a height such that a product stack having a top edge positioned at any point along the face of the swing seat creates a seal between the intake opening and the stack via the swing seal, the side seals, and the bottom seal. Thus, stacks of varying heights may automatically be accommodated. Further, the bottom edge of the swing seal may be beveled, such that if a product stack is not evenly stacked a portion of the uneven stacking will not catch against the swing seal when the stack is pulled away from the opening. | 5 |
FIELD
[0001] This disclosure relates generally to information handling systems, and more specifically, to adaptable power-budget for mobile devices.
BACKGROUND
[0002] As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
[0003] Some information handling systems are implemented as mobile data devices. Mobile date devices include smartphones, tablets and hybrids. One major problem with such devices has been effective management of battery usage, because mobile devices are generally designed to be used untethered from a wired power supply and operated for extended periods on a battery. Some tablet and hybrid devices have battery cycles that last for nearly 10 hours; however, use of internet or graphic rich applications drain the battery more quickly, which may cause the device to turn off. Problematically, critical operations may be hindered when the battery loses power and the device shuts off.
[0004] Because of battery life issues, users of mobile devices often try to limit power usage by limiting use of 3G or 4G communications, disabling use of background synchronization processes and reduce the screen brightness. Unfortunately, these types of measures limit the full use and functionality of the mobile device.
SUMMARY
[0005] Embodiments of methods and systems for adaptable power-budget for mobile devices are presented. In an embodiment, a method may include determining a classification of processes to be executed by a processing device. Such a method may also include detecting a process to be executed by the processing device. Additionally, the method may include selectively providing power to the processing device from one or more of a primary battery and a secondary battery in response to the classification of the detected process.
[0006] In an embodiment, the classification of processes is organized according to a hierarchy. The processes may be classified according to a ring hierarchy, each ring being assigned a priority level, the priority level determining which of the primary battery or the secondary battery is selected to provide power to the processing device.
[0007] In some embodiments, the method may include providing an initial template for the classification of processes that are initially installed for execution by the processing device. The initial template may be updatable in response to an identified process usage pattern. In another embodiment, the initial template is updatable in response to a user input.
[0008] In an embodiment, selectively providing power to the processing device includes determining a charge level of the primary battery. Selectively providing power to the processing device may also include determining a charge level of the secondary battery.
[0009] In an embodiment, the method may include limiting execution of the detected process in response to the classification of the detected process and in response to a measurement of a charge level of at least one of the primary battery and the secondary battery.
[0010] An information handling system is also presented. In an embodiment, the system may include a processing device configured to execute one or more processes. The system may also include a battery unit configured to determine a classification of processes to be executed by the processing device, detect a process to be executed by the processing device, and selectively provide power to the processing device from one or more of a primary battery and a secondary battery in response to the classification of the detected process.
[0011] An apparatus is also described. In some embodiments, the apparatus may include a processing device configured to execute one or more processes, and determine a classification of processes to be executed by the processing device, detect a process to be executed by the processing device, and selectively provide power to the processing device from one or more of a primary battery and a secondary battery in response to the classification of the detected process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention(s) is/are illustrated by way of example and is/are not limited by the accompanying figures, in which like references indicate similar elements. Elements in the figures are illustrated for simplicity and clarity, and have not necessarily been drawn to scale.
[0013] FIG. 1 is a schematic block diagram illustrating one embodiment of an information handling system for adaptable power-budget.
[0014] FIG. 2 is a schematic block diagram illustrating one embodiment of a battery unit for adaptable power-budgeting in a mobile device.
[0015] FIG. 3 is a schematic block diagram illustrating one embodiment of a circuit for adaptable power-budgeting in a mobile device.
[0016] FIG. 4 is a schematic diagram illustrating one embodiment of a state diagram for adaptable power-budgeting in a mobile device.
[0017] FIG. 5 is a schematic diagram illustrating one embodiment of a process priority diagram for adaptable power-budgeting in a mobile device.
[0018] FIG. 6 is a flowchart diagram illustrating one embodiment of a method for adaptable power-budgeting in a mobile device.
DETAILED DESCRIPTION
[0019] The proposed solution is based on an adaptive learning system for profiling the battery usage per process, and adding a compartmentalized battery for servicing the highest priority process as decided by the algorithm on top. The compartmentalized battery is a unique concept where two batteries will be housed as a single unit but the reserve battery will be used only when the algorithm decides that a process needs to use it.
[0020] FIG. 1 is a schematic circuit diagram illustrating one embodiment of an information handling system 102 for adaptable power-budgeting in a mobile device. In various embodiments, a mobile device may include a smartphone, a mobile data device, a mobile music player, a tablet computer device, a laptop computer device, a Global Positioning Satellite (GPS) device, or the like. One of ordinary skill will recognize a wide variety of mobile devices with which the present embodiments may be suitably employed.
[0021] For purposes of this disclosure, an information handling system 102 may include any instrumentality or aggregate of instrumentalities operable to compute, calculate, determine, classify, process, transmit, receive, retrieve, originate, switch, store, display, communicate, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system 102 may be a personal computer (e.g., desktop or laptop), tablet computer, mobile device (e.g., personal digital assistant (PDA) or smart phone), server (e.g., blade server or rack server), a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system 102 may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system 102 may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, touchscreen and/or a video display. The information handling system 102 may also include one or more buses operable to transmit communications between the various hardware components.
[0022] In an embodiment, the information handling system 102 may include a battery unit 104 , a processor 110 , a memory device 112 , and a display device 114 . In such an embodiment, the battery unit 104 may include a primary battery 106 and a secondary battery 108 . Examples of batteries that may be used according to the present embodiments include lithium-ion battery cells, and the like. In an embodiment, the primary battery 106 may be larger and/or hold more charge than the secondary battery 108 . The battery unit 104 may be used to power other components of the information handling system 102 , including for example, the processor 110 , the memory device 112 , and the display device 114 . One of ordinary skill will recognize additional components which may be powered by the battery unit 104 , including a network interface device, etc.
[0023] FIG. 2 illustrates a further embodiment of a battery unit 104 . In the embodiment of FIG. 2 , the battery unit 104 may include the primary battery 106 and the secondary battery 108 as described above. In addition, however, the battery unit 104 may include one or more battery power management controllers, such as battery charging circuit 202 , battery controller(s) 204 , and battery switch 206 .
[0024] In an embodiment, the battery charging circuit 202 may receive charge from an external power source, such as a wall plug or transformer, and apply the charge to either the primary battery 106 , the secondary battery 108 , or both. In a further embodiment, the battery charging circuit 202 may transfer charge from the primary battery 106 to the secondary battery 108 , or vice versa, in response to a determination that a charge imbalance exists. In some embodiments, the battery charging circuit 202 may monitor a charge level on the primary battery 106 , the secondary battery 108 , or both.
[0025] In an embodiment, the battery controller 204 may receive a signal from one or more external battery management modules, an external power source, the battery charging circuit 202 , or the like, and selectively engage the battery switch 206 in response to the received signal(s). For example, the battery controller 204 may receive a signal indicating that power is available from an external power supply, and a second signal indicating that the power level of the primary battery 106 is below a threshold value. In response, the battery controller 204 may cause the battery switch 206 to supply power from the external power source through the battery charging circuit 202 to the primary battery 106 . In other embodiments, as described below, the battery controllers 204 may cause the battery switch 206 to selectively supply power to the information handling system 102 from either the primary battery 106 , or the secondary battery 108 , depending upon the type of process to be handled by the processor 110 .
[0026] FIG. 3 is a schematic block diagram illustrating one embodiment of a circuit 300 for adaptable power-budgeting in a mobile device. In an embodiment, blocks 302 - 310 may be implemented in the battery controller 204 that is internal to the battery unit 104 . In other embodiments, aspects of blocks 302 - 310 may be implemented in the processor 110 , or in other dedicated hardware, such as an Application Specific Integrated Circuit (ASIC), chipset, or the like. One of ordinary skill may recognize various ways of implementing blocks 302 - 310 .
[0027] In an embodiment, the template manager 308 will maintain a process hierarchy or priority ranking. Additionally, the template manager 308 may maintain process rings or levels that may be created according to the hierarchical levels, as described below with relation to FIG. 4 .
[0028] In an embodiment, the template manager 308 may be pre-loaded with an initial usage template. For example, the initial usage template may define whether the process that are operated by the stock or natively installed applications or processes are to be assigned to the primary battery 106 or to the secondary battery 108 . In an embodiment, the template manager 308 may update the template in response to usage data collected during use of the system, or in response to installation of new applications or execution of new processes. In still a further embodiment, the template manager 308 may update the template in response to user input received via the user interface 314 .
[0029] The process map manager 304 may map processes 312 executed by the processor 110 with battery preferences in the template. In certain embodiments, the process map manager 304 may collect process execution data, which may be sent to the process tree refresh manager 306 for updating the battery preferences maintained by the template manager 308 . For example, process execution data may include the frequency of execution of the process, measurements of the duration of process execution, process priority designations from the user, etc. In further embodiments, the process tree refresh manager 306 may additionally receive user preferences via the user interface 314 for updating the battery preferences managed by the template manager 308 . In an embodiment, the application manager 310 may receive or generate new information in response to newly installed applications, deleted applications, application priority changes, application run-time settings, running applications, dormant applications, etc. The application manager 310 may pass on these settings to the template manager 308 for updating the process battery preferences.
[0030] In certain embodiments, the battery manager 302 may include the battery charging circuit 202 , the battery controllers 204 , the battery switch 206 , and all associated functions as described in FIG. 2 . In the embodiment of FIG. 3 , the battery manager 302 may be external to the battery unit 104 , and the battery unit 104 may include a primary battery 106 and a secondary battery 108 . In certain embodiments, the battery manager 302 may provide feedback to the process manager 304 , including battery charge levels, etc. The process manager 304 may then determine whether a given process should be executed by the processor 110 using power from the primary battery 106 or using power from the secondary battery 108 . The process manager 304 may further send a switching signal to the battery manager 302 indicating which battery should provide the power.
[0031] FIG. 4 is a schematic diagram illustrating one embodiment of a state diagram 400 for adaptable power-budgeting in a mobile device. In an initial state 402 , the device may operate according to a predetermined template of application or process priorities and battery usage profiles. In certain embodiments, the template may define a process or application hierarchy. In some embodiments, the hierarchy may be expressed as rings, where processes or applications assigned to a first ring are given a first priority and processes or applications assigned to a second ring are given a second priority. One of ordinary skill may recognize alternative hierarchy definitions or organizations which may be suitable according to the present embodiments.
[0032] Process usage data may be collected, by the process map manager 304 for example, and a process usage pattern may be established. After a predetermined refresh period, the rings may be created or updated based upon the process usage pattern 404 and the device may enter a first state 406 wherein the hierarchy is established or updated. In an embodiment, the process usage pattern 408 may be further monitored and updated as shown at 408 . At a second state 410 , the hierarchy may be updated with the further usage pattern 408 . At a third state 414 , the hierarchy may be updated with usage pattern intervention data 412 received from a user, e.g., via the user interface 314 . This process may run in a continuous loop as shown at 416 .
[0033] FIG. 5 is a schematic diagram illustrating one embodiment of a process priority diagram for adaptable power-budgeting in a mobile device. The diagram of FIG. 5 illustrates one example of a ring hierarchy 500 , where system processes and/or applications are arranged in a set of priority rings 502 - 510 . For example, all kernel and system processes may be designated as first level priority and assigned to the first ring 502 . In such an embodiment, the kernel and system processes, may receive the highest priority and access to resources from both the primary battery 106 and the secondary battery 108 . Basic communication functionality like telephony or text messaging (SMS) may be assigned to a second priority ring 504 and assigned resources from the primary battery 106 and/or the secondary battery 108 , depending upon system battery resources, usage patterns, and/or user designations. Medium priority services, such as email, MMS, WiFi communications, or mobile data services may be assigned to a medium level priority, such as the third ring 506 . Such processes may be granted access to resources from the primary battery 106 and the secondary battery 108 , but only in limited circumstances as defined by the usage patterns and the battery priority profile. Lower-priority, but often used processes may be assigned to the fourth ring 508 , which may not be able to use the secondary battery 108 . Finally, in an embodiment, the lowest priority applications and processes may be assigned to the lowest level, or the fifth ring 510 in this example. In such an embodiment, the applications in the fifth ring 510 may not be provisioned with resources from the secondary battery 108 , and may only be allowed to operate when the primary battery 106 is charged above a threshold value.
[0034] FIG. 6 is a flowchart diagram illustrating one embodiment of a method for adaptable power-budgeting in a mobile device.
[0035] The terms “tangible” and “non-transitory,” as used herein, are intended to describe a computer-readable storage medium (or “memory”) excluding propagating electromagnetic signals; but are not intended to otherwise limit the type of physical computer-readable storage device that is encompassed by the phrase computer-readable medium or memory. For instance, the terms, “non-transitory computer readable medium” or “tangible memory” are intended to encompass types of storage devices that do not necessarily store information permanently, including, for example, RAM. Program instructions and data stored on a tangible computer-accessible storage medium in non-transitory form may afterwards be transmitted by transmission media or signals such as electrical, electromagnetic, or digital signals, which may be conveyed via a communication medium such as a network and/or a wireless link.
[0036] It should be understood that various operations described herein may be implemented in software executed by logic or processing circuitry, hardware, or a combination thereof. The order in which each operation of a given method is performed may be changed, and various operations may be added, reordered, combined, omitted, modified, etc. It is intended that the invention(s) described herein embrace all such modifications and changes and, accordingly, the above description should be regarded in an illustrative rather than a restrictive sense.
[0037] Although the invention(s) is/are described herein with reference to specific embodiments, various modifications and changes can be made without departing from the scope of the present invention(s), as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present invention(s). Any benefits, advantages, or solutions to problems that are described herein with regard to specific embodiments are not intended to be construed as a critical, required, or essential feature or element of any or all the claims.
[0038] Unless stated otherwise, terms such as “first” and “second” are used to arbitrarily distinguish between the elements such terms describe. Thus, these terms are not necessarily intended to indicate temporal or other prioritization of such elements. The terms “coupled” or “operably coupled” are defined as connected, although not necessarily directly, and not necessarily mechanically. The terms “a” and “an” are defined as one or more unless stated otherwise. The terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”) and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more elements possesses those one or more elements but is not limited to possessing only those one or more elements. Similarly, a method or process that “comprises,” “has,” “includes” or “contains” one or more operations possesses those one or more operations but is not limited to possessing only those one or more operations. | Embodiments of methods and systems for adaptable power-budget for mobile devices are presented. In an embodiment, a method may include determining a classification of processes to be executed by a processing device. Such a method may also include detecting a process to be executed by the processing device. Additionally, the method may include selectively providing power to the processing device from one or more of a primary battery and a secondary battery in response to the classification of the detected process. | 8 |
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to a temperature regulating warmth retention material. In particular, the present invention relates to a method for producing a fluffy temperature regulating warmth retention material and the fluffy temperature regulating warmth retention material produced therefrom.
BACKGROUND ART
[0002] Common warmth retention materials available from the market include primarily natural flocculus (including cotton, wool, feather, and the like) and synthetic flocculus (primarily synthetic fiber flocculus ). The principle of warmth retention of such flocculus is to retain still air as more as possible thereby preventing or isolating the flow of heat. Accordingly, a warmth retention material is required to have, or to be form as, a fluffy structure.
[0003] A warmth retention material comprises a phase change material incorporated therein to achieve temperature regulation of the object that is kept warm, wherein the phase change material may be distributed on the top and bottom surfaces of the warmth retention material, or entered the same with a decreasing gradient. On one hand, a high content of the phase change material results in a good temperature regulating effect, but it may make the warmth material harder in hand feeling. Meanwhile, the thickness of the material would also decrease, which would affect the filling power of the same. On the other hand, in order to impart wash resistance, the phase change material is typically applied to, or retained within the warmth retention material by dipping, or drawing and stretching in combination with surface spray coating and secured by hydroentangling, needle punching, or the like. These processes for incorporating a phase change material and securing the warmth retention material, i.e. dipping, drawing, hydroentangling and needle punching, would make the warmth retention material become dense and thinner, and the filling power of the same would decrease and the hand feeling would be harder as compared with the warmth retention material that is not incorporated with the phase change material. Therefore, when this warmth retention material is used in garments, bedding articles, it needs to be improved. Chinese patent application publication CN 102561027 A discloses a flocculus with smart temperature regulating function and a method for preparing the same. According to the description, a flocculus with smart temperature regulating function is formed by combination of a phase change material and a flocculus substrate by padding, soaking for water absorption, spray coating and sprinkling, spray coating, among others, wherein the method comprises mixing the stock fibers, carding the mixed fibers, lapping to form a fiber web, drawing and stretching the fiber web, and spray coating onto both surfaces of the fiber web with a mixture solution of the phase change material and an adhesive.
[0004] Chinese patent application publication CN 102587150 A discloses a method of producing an energy storage nonwoven fabric fiberfill. According to the description, the method comprises (by following the basic manufacturing process of a melt-blown non-woven fabric): using a high polymer raw material for producing the non-woven fabric as the principal raw material and mixing a phase change microcapsule with a UV curable resin in a certain ratio; spray coating the mixture onto the surfaces of the thin non-woven layer; curing; placing the resulting non-woven fabric on web forming curtain; repeating blowing decomposition to thicken the non-woven fabric; and securing by hydroentangling, needle punching, heat punching, and the like to form the energy storage nonwoven fabric fiberfill.
[0005] Apparently, with respect to such warmth retention materials, there are still some problems in incorporating sufficient phase change material into a warmth retention material and keeping it securely therein, and thus providing a desired temperature regulating performance and wash resistance, as well as retaining a sufficient filling power and good hand feeling, and such problems need to be addressed.
SUMMARY OF THE INVENTION
[0006] The objective of the present invention is to provide a method for producing a fluffy temperature regulating warmth retention material and the fluffy temperature regulating warmth retention material produced therefrom.
[0007] As an aspect of the present invention, a method for producing a fluffy temperature regulating warmth retention material is provided. The method comprises: selecting a low melting point fiber and an additional fiber; carding to form a single web; spray coating a phase change material along at least a portion of the length of the single web; lapping layer by layer the single web; and performing a heat setting securing to form the warmth retention material.
[0008] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the low melting point fiber is 6% to 20% (weight percentage, the same below) of the total fiber.
[0009] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the low melting point fiber is selected from a terylene low melting point fiber, a polypropylene low melting point fiber or a polyethylene low melting point fiber.
[0010] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the low melting point fiber is selected from one of a skin-core type low melting point fiber, or a parallel type low melting point fiber.
[0011] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the additional fiber is selected from one or more of a natural fiber, a synthetic fiber, or a regenerated fiber.
[0012] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, a phase change material having a net content of 10% to 55% of the total weight of the temperature regulating warmth retention material is spray coated on a surface of the single web.
[0013] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the phase change material is spray coated at an interval of the same distance or at an interval of different distances along the length direction of the surface of the single web.
[0014] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the phase change material is spray coated along the length of the surface of the single web in a consecutive manner.
[0015] Preferably, the method for producing a fluffy temperature regulating warmth retention material of the present invention comprises a step of preheating the single web after the phase change material is spray coated along at least part of the length of the surface of the single web.
[0016] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the preheating is performed at a temperature of 60° C. to 80° C. (Celsius degree, the same below), for 5 to 15 s (Second, the same below).
[0017] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the single web is lapped layer by layer by cross lapping.
[0018] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, two single web which are not spray coated with the phase change material are lapped layer by layer with at least one single web which is spray coated with the phase change material, and the single web which is spray coated with the phase change material is placed in the middle.
[0019] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the heat setting securing comprises performing a step of spray coating a glue on the outer surfaces of the flocculus formed by lapping layer by layer of the single web, and drying the same.
[0020] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, a glue selected from one of an acrylic copolymer emulsion, a polyvinyl acetate emulsion, and a vinyl acetate-acrylic copolymer emulsion is used in the step of spray coating a glue, and the solid content of the glue spray coated is 2 to 15 grams per square meter (hereafter “gsm”).
[0021] Preferably, in the method for producing a fluffy temperature regulating warmth retention material of the present invention, the drying step is performed at a temperature of 130° C. to 150° C. for 5 to 15 minutes (hereafter “min”).
[0022] As another aspect of the present invention, a fluffy temperature regulating warmth retention material produced according to the method of the present invention is provided. The fluffy temperature regulating warmth retention material comprises multiple single web layers which are lapped layer by layer, wherein the surfaces of at least part of the multiple single web layers are spray coated with a phase change material, and the at least part of the multiple single web layers comprises a low melting point fiber and an additional fiber.
[0023] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the low melting point fiber is 6% to 20% of the total weight of the fiber.
[0024] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the low melting point fiber is selected from a terylene low melting point fiber, a polypropylene low melting point fiber or a polyethylene low melting point fiber.
[0025] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the low melting point fiber comprises a skin-core type low melting point fiber.
[0026] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the low melting point fiber is of a gauge in a range of 1.5 to 7 Denier (a fiber fineness unit, hereafter “D”).
[0027] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the additional fiber is selected from one or more of a natural fiber, a synthetic fiber, or a regenerated fiber.
[0028] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the phase change material is a phase change microcapsule, and the core material of the phase change microcapsule is selected from one or more of a paraffin, an n-alkane compound, a halogenated n-alkane compound or an aliphatic ester, or a mixture of several of them.
[0029] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the phase change material has a weight of 10% to 55% of the total weight of the temperature regulating warmth retention material.
[0030] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the phase change material has a weight of 25% to 50% of the total weight of the temperature regulating warmth retention material.
[0031] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the phase change material is spray coated on a surface of each of the single web layer.
[0032] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the phase change material is spray coated on a surface of every two single web layers.
[0033] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the phase change material is spray coated on a surface of the single web in the middle portion.
[0034] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, a glue is spray coated onto the outer surfaces of the fluffy temperature regulating warmth retention material at a net content level of 2 gsm to 15 gsm.
[0035] Preferably, in the fluffy temperature regulating warmth retention material produced according to the method of the present invention, the outer surfaces of the fluffy temperature regulating warmth retention material is spray coated with a glue selected from one of an acrylic copolymer emulsion, a polyvinyl acetate emulsion, and a vinyl acetate-acrylic copolymer emulsion.
[0036] According to the present invention, a method for producing a fluffy temperature regulating warmth retention material and the fluffy temperature regulating warmth retention material produced in accordance with the method can be provided, wherein the phase change material may be selectively distributed on certain several layers or each layer of the single web, which can upload an appropriate ratio, or more, of the phase change material. The present invention exhibits an apparent temperature regulating function.
[0037] According to the present invention, a low melting point fiber material may be used, and the outer surfaces of the flocculus formed upon completion of the lapping layer by layer of the single web may be spray coated with a glue and then dried to secure by adhesion the phase change material more firmly within the warmth retention material with the assisting cohesive action of the low melting point fibers and the spray coated glue, thereby eliminating the necessity of employing the conventional dipping, drawing, hydroentangling, and needle punching processes.
[0038] Therefore, according to the present invention, a fluffy temperature regulating warmth retention material comprising an appropriate ratio of a phase change material may be obtained and the warmth retention material exhibits a satisfactory temperature regulating effect, and meanwhile, it can retain, to the full extent, or is close to, the original filling power and soft hand feeling where no phase change material is incorporated. In addition, the phase change material can be retained very well within the fluffy temperature regulating warmth retention material and thus the material has a wash resistance property. Furthermore, various fibers may be selected to form the fluffy temperature regulating warmth retention material such that the present invention can be widely used, such as for example, in various garments, shoes and hats, and bedding products.
BRIEF DESCRIPTION OF THE DRAWING
[0039] FIG. 1 is a schematic diagram of the fluffy temperature regulating warmth retention material produced in accordance to the first Example of the method of the present invention;
[0040] FIG. 2 is schematic diagram of the fluffy temperature regulating warmth retention material produced in accordance to the second Example of the method of the present invention;
[0041] FIG. 3 is a schematic diagram of the third Example in accordance with the method of the present invention;
[0042] FIG. 4 is a schematic diagram of the fluffy temperature regulating warmth retention material produced in accordance to the third Example of the method of the present invention.
[0043] The present invention will be described in more detail by particular examples in combination with the accompanying drawings. The accompanying drawings are merely schematic and not drawn to scale, and the examples are merely exemplary and should not be interpreted as limiting the scope of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0044] According to an aspect of present invention, a method for producing a fluffy temperature regulating warmth retention material is provided. The method comprises: selecting a low melting point fiber and an additional fiber, such as for example, one or more of various natural fibers, or synthetic fibers, or regenerated fibers; treating conventionally the fibers selected by mixing, opening and cotton feeding; then carding and forming a single web; spray coating a phase change material along at least a part of the length of the single web; then lapping layer by layer the single web to form a flocculus ; and heat setting to reinforce the flocculus to form the warmth retention material.
[0045] According to the method of the present invention, the low melting point fiber refers to a fiber having a melting point that is lower than 150° C. The melting points of currently available low melting point fibers are in a range of 110° C. to 130° C. The low melting point fiber may be selected from one or more of a terylene low melting point fiber, a polypropylene low melting point fiber or a polyethylene low melting point fiber, and may be 6% to 20% of the total weight of the fiber. The gauge of the low melting point fiber may be 1.5 D to 7 D, and the length of the same is preferably from 38 mm to 64 mm. The remaining additional fiber, which is 80% to 94%, may use a natural fiber such as a cotton fiber, a wool fiber, and the like; or a synthetic fiber such as a terylene fiber, a polypropylene fiber, an acrylic fiber, and the like; or a regenerated fiber such as a viscose fiber, and the like. Any one of the listed fiber may be used alone, or a mixture of two or more fibers from the same type or different types may be used.
[0046] According to the present invention, after the fibers are subjected to carding and formed into a single web, a phase change material is spray coated onto the surface of the single web, which can be achieved by a method of spray coating a phase change microcapsule emulsion. A conventional phase change microcapsule emulsion product comprises a phase change microcapsule as the phase change material and its content is from 15% to 50%, and the remaining comprises water, an emulsifier, a crosslinking agent, a dispersing agent, etc., wherein the size of the microcapsule is in a range of 0.1 to 50 microns. Commercially available phase change microcapsule emulsion products comprise, for example, Standard-22% phase change microcapsule emulsion produced by Shenzhen Yingbao Development Co., Ltd, among others. In this invention, a certain amount of phase change microcapsule emulsion is spray coated such that, in the obtained temperature regulating warmth retention material, the net content of the phase change microcapsules is from 10% to 55% of the total weight of the temperature regulating warmth retention material, or preferably, from 25% to 50%, which is better.
[0047] The phase change material may be spray coated for a certain length along the web surface, and this may be repeated with an interval having the same length or different lengths. Alternatively, the phase change material may be spray coated in a continuous manner along the length of the single web surface. Preferably, the certain length along the surface of the single web that is spray coated with the phase change material is determined in accordance with the predetermined width of the temperature regulating warmth material, such as for example, being equal to the width, or two or several times of the width.
[0048] Preferably, a pre-drying for 5 to 15 seconds is performed upon completion of the spray coating. The temperature for the pre-drying is from 60° C. to 80° C. to facilitate retention of the phase change material during the process.
[0049] Next, the single web is lapped layer by layer and this can be carried out by a conventional cross lapping technique, i.e. the single web are driven by a lapping machine moving back and forth to fold and lap layer by layer the single web in the width direction of the lapping machine onto a web delivery curtain moving at a certain speed, thereby forming a flocculus with a certain thickness. Generally, the lapping is performed in accordance with the breadth of the lapping machine. In other words, the breadth of the lapping machine will determine the width of the flocculus thus formed. For the single web layers lapped in this manner, at least part of the single web layers is spray coated with the phase change material. For example, where the spray coating of the phase change material is performed along the length direction of the single web with a length determined by the breadth of the lapping machine, and repeated at an interval of the same length, and then the folding and lapping of the layers of the cross lapping is performed in accordance with the breadth of the lapping machine, the flocculus obtained from the cross lapping would be one formed by lapping of multiple single web layers wherein one of every two single web layers is spray coated with the phase change material. Where the spray coating is performed in a continuous manner, the flocculus obtained from the cross lapping would be one formed by lapping of multiple single web layers wherein each single web layer is spray coated with the phase change material. In this case, based on the direction of the cross lapping, such as for example, with respect to a back and forth folded lapping, the surfaces of the single web layers which are spray coated with the phase change material will be opposite to each other, i.e. they are lapped in a face-to-face manner; where the lapping is performed in the same direction, then the surfaces of each single web layer which are spray coated with the phase change material are facing the same direction, i.e. the surface of the single web which is spray coated with the phase change material is lapped directly with the surface of another single web which is not spray coated with the phase change material.
[0050] Apparently, a flocculus having a layer or several selected layers spray coated with the phase change material may be formed by adjusting the length and the period of time of spray coating the phase change material along the surface of the single web, and the manner of cross lapping. For example, a flocculus with only several middle single web layers being spray coated with the phase change material may be formed.
[0051] Alternatively, a flocculus with only several selected layers spray coated with the phase change material may also be formed by cross lapping a single web which is spray coated with a continuous phase change material and two or at least two single webs which are not spray coated with the phase change material. For example, a flocculus with only several middle single web layers being spray coated with the phase change material may be obtained by placing the single web spray coated with the phase change material on its surface in the middle.
[0052] A glue spray coating and drying step may be performed for heat setting reinforcement of the flocculus obtained by cross lapping. The glue spray coating is performed on the outer surfaces of the flocculus to obtain a solid content of 2 gsm to 15 gsm, and the glue may be one of the following: an acrylic copolymer emulsion, a polyvinyl acetate emulsion, or a vinyl acetate-acrylic copolymer emulsion. Then, the drying is performed at a temperature of 130° C. to 150° C. for 5 to 15 minutes to achieve a fluffy temperature regulating warmth retention material.
[0053] For carrying out the method of the present invention, with respect to the existing non-woven carding and cross lapping process, a spray coating device and a pre-drying device may be incorporated between the carding machine and the cross lapping machine to achieve spray coating of the phase change material and pre-drying. Additionally, a glue spray coating device and a drying device may be provided after the cross lapping machine to achieve glue spray coating and drying of the flocculus . Such arrangements can be achieved by using the prior art. In this way, a more complete process, which comprises the existing process and the method of the present invention, for producing a fluffy temperature regulating warmth retention material from fibers, can be listed as below:
[0054] Selecting a low melting point fiber and an additional fiber—mixing the fibers—coarse opening—fine opening—carding—spray coating a phase change material—pre-drying—cross lapping—spray coating a glue on both the surfaces—drying reinforcement—cutting and winding.
[0055] According to an aspect of the present invention, a fluffy temperature regulating warmth retention material produced in accordance with the present invention may be provided. The fluffy temperature regulating warmth retention material comprises multiple single web layers lapped layer by layer, wherein the surfaces of at least part of the multiple single web layers are spray coated with a phase change material, such as several certain layers (for example, several middle layers), or every alternate layer, or each layer, or any selected layer or layers of the single web, depending on the needs.
[0056] The fluffy temperature regulating warmth retention material produced in accordance with the method of the present invention comprises a low melting point fiber which can thus be adhered to different fibers, such that the single web has a certain strength. Suitable ratios of the fibers are: low melting point fiber: 6-20%; additional fiber: 80-94%. The gauge of the low melting point fiber may be 1.5 D-7 D with a length of 38 to 64 mm. The low melting point fiber material may be selected from one of a terylene low melting point fiber, a polypropylene low melting point fiber or a polyethylene low melting point fiber. The low melting point fiber structure may be selected from a synthetic fiber skin-core structure, or a parallel structure, or the like, such as Huvis 2080, ES fiber and the like that are commercially available.
[0057] The additional fiber included in the fluffy temperature regulating warmth retention material produced in accordance with the method of the present invention may comprise a natural fiber, such as cotton, wool, and the like; or a synthetic fiber, such as a terylene fiber, a polypropylene fiber, an acrylic fiber, and the like; or a regenerated fibers such as a viscose fiber, and the like. Any one of the listed fiber may be used alone, or a mixture of two or more fibers from the same type or different types may be used. The gauge of the employed natural fiber, synthetic fiber or regenerated fiber may be 0.7 D to 10 D and with a length of 10 mm to 80 mm. Preferably, the fluffy temperature regulating warmth retention material comprises a hollow three dimensional crimped fiber having a gauge of 0.7 D to 10 D and with a length of 10 mm to 80 mm. For example, commercially available ones are, Yizheng 3D hollow three dimensional crimped silica-containing fiber, Yuanfang 2D solid silica-free fiber, and the like. The hollow fibers included in the flocculus are helpful in keeping the flocculus fluffy.
[0058] Where the fluffy temperature regulating warmth retention material produced in accordance with the method of the present invention is used in a garment or a bedding article application, the appropriate phase change temperature is generally between 15° C. to 35° C., and the suitable phase change material may be a phase change microcapsule having a net content of 10% to 55% of the total weight of the temperature regulating warmth retention material, or preferably, 25% to 50%, which is better. In this invention, the wall material of the phase change microcapsule included in temperature regulating warmth retention material may be selected from one of a polyethylene polymer, an alkyl polyacrylic polymer or a polyurethane polymer, and the like, and the core material of the same may be a paraffin, an n-alkane compound, a halogenated n-alkane compound, or an aliphatic ester, or a mixture of several of them.
[0059] The fluffy temperature regulating warmth retention material produced in accordance with the method of the present invention may be subjected to a glue spray coating treatment and in this way, the outer surfaces of the material may be spray coated with a glue. Preferably, the solid content of the glue, i.e. the dry weight of the glue per square meter flocculus is in a range of 2 gsm to 15 gsm, and more preferably, 4 gsm to 10 gsm. Suitable glues comprise one of acrylics or epoxy resins or EVAs, such as for example, 201 mid-soft (produced by Quansong, Yixing), EXP3267 (Rohm and Haas), among others, which are commercially available.
Example 1
[0060] 2 kg of 2 D*51 mm terylene low melting point fibers (Huvis 2080, produced by Huvis Corporation) were used. The additional fibers were 5 kg of 2 D*51 mm solid fibers (SN-82505, produced by Yuanfang Corporation) and 3 kg of 3 D*64 mm hollow crimping fibers (YZK4133D hollow fiber, produced by Yizheng Corporation). After being processed by mixing—coarse opening—fine opening—feeding—carding, a single web 10 was obtained. Then, a phase change material, i.e. a phase change microcapsule emulsion having a core material of an n-alkane (n-octadecane) produced by Shenzhen Yingbao Corporation was spray coated consecutively and the amount of spray was controlled such that the net content of the phase change microcapsules 20 is 55% of the total weight of the single web 10 , and then pre-dried at 80° C. for 5 seconds, and then the single web 10 was cross lapped layer by layer to form a flocculus . When subjected to a heat setting reinforcement, the outer surfaces of the flocculus as formed were spray coated with a glue and dried, wherein EXP3267 acrylic copolymer emulsion glue (Rohm and Haas) was used and the amount of spray was controlled such that the solid content of the spray coated glue was 4 gsm. Then the resulting flocculus was dried at 135° C. for 12 minutes to form a structure having the phase change microcapsules disposed on each single web layer 10 of the temperature regulating warmth retention material, as illustrated in FIG. 1 .
Example 2
[0061] 1.5 kg of 2 D*51 mm low melting point fibers (130° C.) (ES polyethylene/polypropylene fiber, produced by Guangzhou ES Fiber Co., Ltd) were used. The additional fibers were 2 kg of natural fiber—cotton, 3 kg of 2 D*51 mm synthetic fibers—solid silica-containing fibers (SN-8250S2D fiber, produced by Yuanfang Corporation) and 3.5 kg of 7 D*64 mm hollow crimping fibers (YZK61A7D hollow fiber, produced by Yizheng Corporation). After being processed by mixing—coarse opening—fine opening—feeding—carding, a single web 10 was obtained. The output speed, lapping speed and the time required for lapping one single web 10 layer were controlled, and an emulsion containing phase change microcapsules 20 was spray coated intermittently at a time interval such that, after cross lapping, one layer of the phase change microcapsules 20 was provided on every two single web 10 layers. MG26 phase change microcapsule emulsion with paraffin cores (produced by Beijing Guangyu Phase Transformation Technology Co., Ltd) was used, and the amount of spray was controlled such that the net content of the phase change microcapsules 20 is 32% of the total weight of two single web 10 layers or the flocculus , and then pre-dried at 70° C. for 10 seconds, and then the single web 10 were cross lapped layer by layer to form a flocculus . When subjected to a heat setting reinforcement, the outer surfaces of the flocculus as formed were spray coated with a glue and dried, wherein the glue is a polyvinyl acetate emulsion (VAE 707 product, produced by Beijing Zhonghui United Company) and the amount of spray was controlled such that the solid content of the spray coated glue was 10 gsm. Then the resulting flocculus was dried at 140° C. for 10 minutes to form a temperature regulating warmth retention material with one phase change microcapsule layer 20 provided on every two single web layers 10 , as illustrated in FIG. 2 .
Example 3
[0062] 0.6 kg of 4 D*51 mm terylene low melting point fibers (4080, produced by Huvis Corporation) were used. The additional fibers were 5.9 kg of 2 D*51 mm solid viscose regenerated fibers (32S viscose fiber, manufactured by Lenzing Corporation) and 3.5 kg of 7 D*64 mm hollow crimping synthetic fibers (YZK61A7D hollow fiber, produced by Yizheng Corporation). After being processed by mixing—coarse opening—fine opening—feeding—carding, a single web 10 was obtained. Then, as illustrated in FIG. 3 , three carding machines were put into operation simultaneously to obtain three identical single webs 10 . Only the single web 10 obtained from the middle carding machine of FIG. 3 was spray coated consecutively with an emulsion containing a phase change microcapsules 20 . A phase change microcapsule emulsion with aliphatic ester cores (produced by Hangtian Haiying (Zhenjiang) Special Materials Co., Ltd) was used, and the amount of spray was controlled such that the net content of the phase change microcapsules 20 is 15% of the total weight of the flocculus , and then pre-dried at 60° C. for 15 seconds, and then the three single webs 10 were cross lapped using three cross lapping machines, and combined and formed as a flocculus and the single web 10 spray coated with the phase change microcapsules 20 was disposed in the central portion of the flocculus . After the cross lapping was completed, a heat setting reinforcement was performed. The outer surfaces of the flocculus as formed were spray coated with a glue and dried, wherein the glue was vinyl acetate-acrylic emulsion (YH-1 glue product, produced by Yixing Jindeli Chemicals Company) and the amount of spray was that the solid content of the glue was 6 gsm. Then the resulting flocculus was dried at 145° C. for 8 minutes to obtain a temperature regulating warmth retention material having the structure as illustrated in FIG. 4 .
[0063] For the purpose of evaluating the materials produced in accordance with the present invention, a common warmth material, i.e. a control sample for comparison with the samples of Examples 1 to 3, was produced in accordance with the process and fibers of Example 2, but the spray coating of a phase change material and the pre-drying were not included. The test results of the properties of the samples are as below:
[0000]
TABLE 1
Properties as measured
Weight-
Weight-
After 5
Weight
PCM
Glue/
Thickness/
Prior to
Washes with
Retention
Sample
%
gsm
cm
Wash/g
Water/g
Rate/%
Example 1
55
4
1.46
55.29
54.02
97.7
Example 2
32
10
1.48
48.41
48
99.2
Example 3
15
6
1.5
37.76
37.23
98.6
Control
0
6
1.41
32.55
32.5
99.8
[0064] It can be seen from the above Table 1 that, compared with the control sample, the samples of the Examples of the present invention do not have substantial change in thickness, and the process does not result in decrease in filling power, which maintains, to the full extent, or is close to, the original filling power and soft hand feeling where no phase change material is incorporated. The weight retention rate after five washes with water may be up to 97% to 99%, indicating no substantial loss of the phase change material.
[0065] Accordingly, the method of the present invention provides a fluffy temperature regulating warmth retention material that can use more phase change material and have it dispersed in the volume of the warmth material to achieve a good temperature regulating performance and avoid the employment of dipping, drawing, hydroentangling, needle punching, which would affect the filling power, thereby retaining the filling power of the temperature regulating warmth retention material and meanwhile, the material has a good hand feeling and a good wash resistance.
[0066] Although the present invention has been described as above in combination with the Examples, it is merely for clarity of the description but not for limiting. The scope of the present invention would rather be defined by the claims. | A method for producing a fluffy temperature regulating warmth retention material and the fluffy temperature regulating warmth retention material produced therefrom are disclosed. The method comprises: selecting a low melting point fiber and an additional fiber; carding to form a single web; spray coating a phase change material along at least part of the length of a surface of the single web; lapping layer by layer of the single web; and performing a heat setting reinforcement to form the warmth retention material. According to the present invention, a fluffy temperature regulating warmth retention material comprising an appropriate ratio of a phase change material may be obtained and the material exhibits a satisfactory temperature regulating effect, and meanwhile, it can maintain, to the full extent, or is close to, the original filling power and soft hand feeling where no phase change material is incorporated. In addition, the phase change material can be retained very well within the fluffy temperature regulating warmth retention material and thus has a wash resistance property. | 3 |
The following U.S. patent is hereby incorporated by reference: U.S. Pat. No. 5,493,423, “Resettable Pixel Amplifier for an Image Sensor Array”, assigned to the Assignee hereof.
FIELD OF THE INVENTION
The present invention relates to an image sensor array, such as found, for example, in digital scanners, copiers, and facsimile machines. More particularly, the present invention relates to a selectable amplifier which can be associated with at least one individual photosensor in such a sensor array.
BACKGROUND OF THE INVENTION
Image sensor arrays typically comprise a linear array of photosensors which scan an image-bearing document and convert the microscopic image areas viewed by each photosensor to image signal charges. Following an integration time, the image signal charges are amplified and transferred to a common output line or bus through successively actuated multiplexing transistors.
In the scanning process, bias and reset charges are applied to each photosensor (such as a photodiode) in a predetermined time sequence during each scan cycle. In a particular embodiment of such an image sensor array, a two-stage transfer circuit is provided for transferring the image signal charges from the photodiodes. A bias charge is applied to each photodiode through a bias charge injection transistor coupled to a node between the photodiode and the input to the transfer circuit. From the transfer circuit, the image-based charges are caused to pass through an amplifier circuit, one amplifier circuit being typically provided for each photodiode, or at least to each RGB-color triplet of color-sensitive photodiodes.
During a readout of the image signals along an array of photodiodes, it is desirable that the individual amplifiers associated with each photodiode be activated only long enough to amplify the image signal being read out from a particular single photodiode; when the particular photodiode is not reading out its image based charge at the moment, it is desirable that the associated amplifier be powered down temporarily. This power-down is desirable from the perspective of lowering the total power requirements of a silicon chip which may have several hundred photodiodes and associated amplifiers thereon, as well as for other reasons.
The present invention is thus directed to a design of an individually-selectable amplifier which can be associated with a single photodiode or other photosensor in an image sensor array.
DESCRIPTION OF THE PRIOR ART
Bazes, “Two Novel Fully Complementary Self-Biased CMOS Differential Amplifiers,” IEEE Journal of Solid - State Circuits , Vol. 26, No. 2, Feb. 1991, pp. 165-168, discloses designs of differential amplifiers having fully complementary configurations and which are self-biased through negative feedback. U.S. Pat. Nos. 4,857,476 and 4,958,133 by the same author show related amplifier designs.
U.S. Pat. No. 5,493,423, incorporated by reference above, discloses an amplifier circuit which can be associated with an individual photosensor in an image sensor array. With each cycle of passing an image signal through an amplifier, a low standby current is applied to certain transistors within the amplifier until the next signal is to be output. Critical nodes within the amplifier are caused to settle to known charge-values before each image signal is passed therethrough.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided an amplifier suitable for processing image signals. An input stage includes a first differential pair including two p-devices and a second differential pair, complementary to the first differential pair, including two n-devices. A first load device supplies current to the first differential pair and a second load device supplies current to the second differential pair, the first load device and the second load device being biased at a common bias node. Self-biasing circuitry generates a bias at the bias node. Means are provided for deselecting the amplifier in response to an external signal, the deselecting means including means for grounding the bias node and means for eliminating current in the self-biasing circuitry in response to the external signal.
According to another aspect of the present invention, there is provided a photosensitive apparatus, comprising a set of photosensors, each photosensor outputting a voltage signal relating to an intensity of light thereon; a set of amplifiers, each amplifier in the set of amplifiers being associated with a photosensor in the set of photosensors, for amplifying a voltage signal from the photosensor; and means for sending a deselection signal to any amplifier. Each amplifier includes an input stage, the input stage having a first differential pair including two p-devices and a second differential pair, complementary to the first differential pair, including two n-devices. A first load device supplies current to the first differential pair and a second load device supplies current to the second differential pair, the first load device and the second load device being biased at a common bias node. Self-biasing circuitry generates a bias at the bias node. Means are provided for deselecting the amplifier in response to the deselection signal, the deselecting means including means for grounding the bias node and means for eliminating current in the self-biasing circuitry in response to the deselection signal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of am image scanning array having an array of photosensor cells, each cell having a photodiode with two-stage transfer circuit and amplifier for transferring image signal charges from the photodiodes to a common output bus;
FIG. 2 is a schematic diagram of a basic, non-selectable amplifier circuit, as could be used in the sensor array of FIG. 1; and
FIG. 3 is a schematic diagram of an amplifier circuit according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown the image sensor array with two stage transfer, designated generally by the numeral 10 , of the type to which the present invention is directed. Image sensor array 10 includes a chip 12 of silicon with a plurality of photosites in the form of photodiodes 14 thereon. Photodiodes 14 are in closely spaced juxtaposition with one another on chip 12 in a linear array or row 16 . Several smaller arrays such as array 10 can be abutted together end to end with one another to form a longer array, i.e., a full width or contact array, with spacing between the photodiodes inside the chip thereby maintaining photodiode pitch across the entire full width of the composite array.
While photodiodes 14 are shown and described herein, other photosite types such as amorphous silicon or transparent electrode MOS type photosites may be envisioned. Further, while a one dimensional sensor array having a single row 16 of photodiodes 14 is shown and described herein, a two dimensional sensor array with plural rows of photodiodes may be contemplated.
Each photodiode 14 has a two stage transfer circuit 20 associated therewith which together with the photodiode and an amplifier 33 form a photosite cell 15 at the array front end. In each cell 15 , the image signal charge from the photodiode 14 is amplified to bring the image signal charge to a desired potential level prior to transferring the charge to a common video output line or bus 22 . Suitable shift register and logic circuitry 24 provides timing control signals ΦPIX (with an optional complement, ΦPIX) for connecting each pixel cell 15 to bus 22 in the proper timed sequence; a shift register such as 24 typically includes a set of stages therein, each stage in this embodiment being associated with one photosite cell 15 , and thus associated with one amplifier, as can be seen as the set of ΦPIX and ΦPIX lines emerging from shift register 24 .
Image sensor array 10 may for example be used to raster scan a document original, and in that application, the document original and sensor array 10 are moved or stepped relative to one another in a direction (i.e., the slow scan direction) that is normally perpendicular to the linear axis of array 10 . At the same time, the array scans the document original line by line in the direction (i.e., the fast scan direction) parallel to the linear axis of the tray. The image line being scanned is illuminated and focused onto the photodiodes 14 . During an integration period, a charge is developed to each photodiode proportional to the reflectance of the image area viewed by each photodiode. The image signal charges are thereafter transferred by two stage transfer circuits 20 via amplifier 33 to output bus 22 in a predetermined step by step timed sequence.
FIG. 2 is a schematic view of a design of amplifier which could be used as amplifier 33 in the context of the image sensor array of FIG. 1 . The amplifier shown in FIG. 2 is conceptually similar to the “very-wide-common-mode-range differential amplifier,” or VCDA, described in the article by Bazes referenced above. Both the FIG. 2 amplifier and the Bazes design represent a CMOS differential amplifier with wide input dynamic range, which is fully complementary and entirely self-biased. Both designs ultimately derive from a combination of two “folded-cascode” differential amplifiers, each the complement of the other, as described in Bazes. The design shown in FIG. 2 is particularly useful for providing a desirably linear unity-gain amplification from zero to VDD (full power supply range).
In overview, the basic amplifier of FIG. 2 functions as follows. The is amplifier, generally indicated as 33 , accepts an image-based voltage signal V input and outputs a voltage signal V output . There is provided, at V input , a differential pair of p-devices M 1 A and M 1 B. The differential pair of p-devices M 1 A and M 1 B are combined as shown with a differential pair of n-devices, M 2 A and M 2 B. The p-devices M 1 A and M 1 B share a common current source, VDD 2 , while the emitters of the n-differential pair M 2 A and M 2 B share a common ground actuable through transistor M 4 . The n-differential pair M 2 A and M 2 B is useful for providing an output V output in the range of 2-5 volts, while the p-differential pair M 1 A, M 1 B is useful for outputting voltages in the range of 0-3 volts. With reference to the claims here inbelow, the set of complementary CMOS transistor pairs M 1 A, M 1 B, M 2 A, and M 2 B forms a folded cascode amplifier in itself and represent the “input stage” for the overall amplifier 33 . The illustrated arrangement has a larger drain-source voltage drop on the input pairs, and thus has greater dynamic range, than ordinary single transistor pair differential amplifiers.
Voltage sources VDD 1 and VDD 3 form balanced rails providing summing current to the two kinds of differential pairs, while the transistors M 10 and M 11 proximate to voltage source VDD 4 form a push-pull output driver stage. (The various voltage sources in the schematic, VDD 1 -VDD 4 are in fact all the same voltage source, but are differently-numbered for reference purposes.) The line connecting V output to the gate of device M 1 A & M 2 A forms the feedback loop which causes the amplifier 33 to be a unity-gain amplifier.
As the input voltage V input rises from a low to high voltage, the p-type input devices M 1 A, M 1 B switch from full conduction to no conduction and the n-type devices M 2 A, M 2 B switch from no conduction to full conduction currents. In other words, the n-channel devices are inactive in the region near ground and the p-channel devices are inactive in the region near VDD. Between these extremes, both pairs are active. In the region where both pairs are on, the transconductance of the input stage is twice as big as in the regions where only one pair (of n-devices or p-devices) is on. The transconductance is proportional to the square root of the saturation drain current of the device. This makes optimal frequency compensation very difficult, because the gain-bandwidth product of an amplifier is proportional to the transconductance of its input stage.
The bias current to the pairs of devices M 1 A, M 1 B and M 2 A and M 2 B in the input stage is supplied by load devices M 3 and M 4 . The currents through load devices M 3 and M 4 must be identical; any differences in currents through M 3 and M 4 devices would result in extreme shifts in amplifier-bias voltages. Therefore, external biasing of load device M 3 for the p-channel pair and load device M 4 for the n-channel pair is not desirable. The self-biasing scheme is created by connecting both M 3 and M 4 to a single internal bias node, indicated as V bias in FIG. 2 . The self-biasing of the amplifier creates a negative-feedback loop that stabilizes the bias voltages for M 3 and M 4 .
The current paths are formed by M 3 , M 1 A, and M 8 A or M 3 , M 1 B, and M 8 B for the p-devices, and are formed by M 5 A, M 2 A, and M 4 or M 5 B, M 2 B and M 4 for the n-devices. Precise balancing of currents through the two paths is dependent on the ratios of the devices M 6 A to M 7 A (and M 6 B to M 7 B) as well as M 5 A to M 8 A (M 5 B to M 8 B). The cascode stage formed by devices M 5 A, M 6 A, M 7 A, and M 8 A on the biasing side, and the cascode stage formed by devices M 5 B, M 6 B, M 7 B, and M 8 B on the output side are identical and complementary to each other. Each cascode stage forms a summing circuit for the currents through transistors M 1 A and M 2 A (or M 1 B and M 2 B) of the input stage. With particular reference to the claims herein below, the cascode stage, formed by M 5 A-M 8 A represents the “self-biasing circuitry” for the self-biasing amplifier, and generate the bias on V bias . Voltage developed at the node V bias is the self-biasing voltage needed to provide the balancing of currents through the input stage.
The cascode stage formed by M 5 B through M 8 B drives the output buffering stage. The output stage is formed by two common-source output transistors M 10 and M 11 . In order to provide a stable operation, capacitors CM 1 and CM 2 are used for frequency compensation. The output is fed back to the inputs of devices M 1 A and M 2 A of the differential amplifier. The input signal is connected to the gates of M 1 B and M 2 B as shown in FIG. 2 . The differential amplifier output is in phase with the input signal.
The load devices M 3 and M 4 are biased by node V bias , and therefore quiescent current in the input stage is always present. The quiescent power consumption by the circuit must be switched off in an application where one or more of these in an array of amplifiers are selected at a time and the others are in deselected mode or powered down. In order to eliminate the current within the amplifier 33 when the amplifier 33 is in a deselected mode, the biasing node V bias needs to be grounded. Returning to FIG. 1, it is most desirable, from the standpoint of overall power consumption of the image sensor array 10 that individual amplifiers 33 be powered up for operation only in the narrow window of time during each readout in which the particular photodiode 14 associated with a single amplifier is transferring a signal therethrough. If a typical sensor array 10 on a single chip 12 includes approximately 250 photodiodes 14 , it will be evident that the overall duty cycle of any individual amplifier 33 will be quite short in proportion to the total time of operation of the image sensor array 10 . It is thus desirable to provide an amplifier design which preserves all of the desirable characteristics of, for example, the amplifier of FIG. 2, but which also is especially suitable for rapid power-up and power-down in the context of an image sensor array.
FIG. 3 is a schematic showing a preferred design of an amplifier incorporating the present invention. Comparing FIG. 2 to FIG. 3, it will be noted that the FIG. 3 schematic includes all of the elements of the FIG. 2 schematic, but in addition includes certain inputs which relate to whether the amplifier 33 is being selected at a particular moment. (The areas of difference between FIG. 2 and FIG. 3 are indicated by the dotted-line boxes in FIG. 3.) It will be noted that the FIG. 3 amplifier includes, in addition to the original inputs and outputs V input and V output , inputs for selecting the amplifier 33 as a whole: as shown in FIG. 3, there are inputs ΦPIX and ΦPIX which are complements of each other. The inputs ΦPIX and ΦPIX are readily derived from the standard suitable shift register and logic circuitry 24 such as shown in FIG. 1 .
It will be noted, in comparing FIG. 2 to FIG. 3, that when an input ΦPIX is high, the schematic of FIG. 3 is identical to the circuit of FIG. 2 : when ΦPIX is high, the amplifier 33 is “selected” and operates as an amplifier. Significantly, when ΦPIX is low, and by definition when ΦPIX is high, the amplifier 33 is powered down.
Looking at the different areas in which a high value of ΦPIX (a “deselect” signal) affects the circuit of FIG. 3, it will first be noted that a high ΦPIX will disconnect the output from any downstream circuitry, as shown at area 50 . A high value of ΦPIX will also create a channel in transistor M 14 , which has the effect of shutting off all the n-devices M 8 A, M 4 , M 8 B (area 52 ). The activation of ΦPIX at area 54 effectively removes any path between the n- and p-devices within the amplifier 33 . Another portion of the schematic of FIG. 3 which differs from FIG. 2, area 56 , has an additional VDD input, VDD 5 , which causes the amplifier 33 to match the impedance of a new signal when the amplifier 33 is next selected.
The purpose of the additional inputs for deselecting and reselecting the amplifier 33 is to eliminate the current from the amplifier 33 when the amplifier 33 is in a deselected mode. To accomplish this effectively, two things must happen: (1) the biasing node V bias needs to be grounded, and (2) the current in the self-biasing portion of the amplifier must have any residual current therein eliminated.
At deselection of amplifier 33 , the biasing node V bias is grounded as follows. The pair of devices in area 54 , devices M 9 A and M 9 B, form a switch with two out of phase control clocks. Similarly, devices M 9 C and M 9 D at area 56 form a switch biased as shown to allow the current to flow through in each direction. The gates of devices M 9 D and M 9 C are connected to VDD 3 and ground, respectively, so that they are conducting at all times. When the amplifier 33 is deselected, devices M 9 A and M 9 B in area 54 are turned off, and device M 14 in area 52 is turned on by the clocks ΦPIX and ΦPIX. This operation pulls down the V bias node to ground and shuts off all n-type devices of the input stage and the output buffer stage, and therefore no current is being drawn by the circuit. The only current drawn is the leakage current through the various n-devices and the CM 1 , CM 2 capacitors.
Further, as mentioned above, to deselect an amplifier 33 properly, the self-biasing circuitry must have all current eliminated therefrom. In the FIG. 3 embodiment, the self-biasing circuitry, which ultimately generates the bias on V bias , is represented by the cascode stages formed by transistors M 5 A-M 8 A and M 5 B-M 8 B. Current is eliminated in these stages by activation of transistor M 14 in area 52 by a high signal ΦPIX on the base thereon. This action, as shown, shuts off all n-devices M 7 A, M 8 A, M 7 B, M 8 B in the cascode stages, and causes any current in transistors M 5 A-M 8 A and M 5 B-M 8 B to be grounded out. In this context the actions of transistors M 9 A-M 9 D are added for range and symmetry reasons: when the amplifier 33 is active or selected, device M 14 in area 52 is turned off and devices M 9 A and M 9 B are turned on by their control clocks, allowing the bias to rise to the necessary DC bias level for devices M 3 and M 4 ; input signal V input can then be observed at the output of the amplifier.
In the FIG. 3 embodiment, the same complementary clock signals are shown controlling both switches M 9 A, M 9 B and M 12 , M 13 . However each switch could be controlled by a separate pair of clock signals. Device M 9 B can be removed from the circuit if the linearity of the amplifier transfer characteristic is acceptable. The clocks used for driving M 9 A and M 14 must be of opposite polarity or be generated by any two non-overlapping clocks.
While the invention has been described in detail with reference to specific and preferred embodiments, it will be appreciated that various modifications and variations will be apparent. All such modifications and embodiments as may occur to one skilled in the art are intended to be within the scope of the appended claims. | A CMOS-based voltage signal amplifier is particularly useful for amplifying signals from a single photodiode, or a small set of photodiodes, within a large photosensitive imaging device. When the imaging device reads out image signals from a large number of photodiodes, each amplifier is selected for operation only within a very brief time window when the particular photodiode associated therewith is reading out. The amplifier of the present design is suitable for rapid power-up and power-down when it is selected and deselected. | 7 |
REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of my copending application Ser. No. 815,921, filed July 15, 1977, now U.S. Pat. No. 4,199,046, which was a continuation-in-part of my application Ser. No. 763,653 filed Jan. 28, 1977 and now abandoned.
FIELD OF THE INVENTION
This invention relates to brake actuating means for pedal-propelled vehicles such as bicycles. Although the invention is also applicable to pedal-propelled vehicles having more than two wheels, e.g. tricycles, it will for convenience hereinafter be explained and described in relation to bicycles, which are by far the most common form of such vehicles, without thereby implying any limitation of the scope of the invention to bicycles.
REVIEW OF THE PRIOR ART
Bicycle brakes are generally of two types, those that are hand operated and those that are foot operated. The most usual foot operated type is generally known as a "coaster" or back-pedalling brake. The braking mechanism of the conventional type of coaster brake is contained in the hub of the rear wheel of the bicycle and the operating force is transmitted by the same chain that is used for propelling the bicycle. The means of operating such a coaster brake is by back-pedalling, the reverse torque from the pedals being carried to the rear wheel via a tension force in the lower strand of the chain. The braking mechanism for a hand operated brake may be either a caliper arrangement which presses on the opposite flat sides of the rim of the wheel, a drum and shoe brake housed in the hub of the wheel, or a disc brake. Other and less satisfactory braking mechanisms have been used in the past for hand operated brakes, such as the simple "spoon" device that presses on the outside of the tire and the "stirrup" device that presses on the inside surface of the rim.
Both hand brakes and coaster brakes have disadvantages. The main disadvantage of the hand brake is the manual force required to apply it. This reduces the sensitivity of the hand for steering the bicycle, especially when one hand is removed from the handle bars.
The main disadvantage of the conventional coaster brake is that it becomes inoperative if the main drive chain accidentally breaks or slips off either the pedal or rear wheel sprocket, whilst it cannot be applied to bicycles equipped with derailleur or similar change-speed gears in which the lower strand of the driving chain cannot be used to transmit any tension force.
It has several times been proposed, in order to overcome the problem, to associate a one way clutch mechanism with the pedal crankshaft, by means of which the back-pedalling effort may be applied to a lever and thence to a brake mechanism which may be of any of the types customarily operated by a hand brake lever.
One group of such proposals makes use of a ratchet and pawl mechanism to provide the one way clutch, but such mechanisms require modification of the pedal crankshaft since either the ratchet or the pawl must be securely fixed to the shaft or incorpoated in it, and will necessarily involve a significant degree of lost motion before full engagement or disengagement is achieved. Moreover, according to the relative angular positions of the ratchet and pawl or pawls, the brake will only be applicable at certain predetermined angular positions of the crankshaft. Certain mechanisms of this type can also lock themselves on, which is at best inconvenient and at worst extremely dangerous.
These problems can be overcome by using a one way clutch of the spring type, as shown in U.S. Pat. No. 1,488,714 issued Apr. 1, 1924, Italian Pat. No. 300,578 issued Sept. 13, 1932, Italian Pat. No. 456,997 issued Apr. 29, 1950 and U.S. Pat. No. 2,940,563 issued June 14, 1960. However, it is significant that although there is currently a well identified market for a coaster type brake for the popular five and ten speed bicycles equipped with derailleur type gears, none of the above inventions appears to have met with acceptance.
The majority of bicycles that are equipped with derailleur or similar change speed gears are manufactured with pedal crankshaft housings about one and a half inches in external diameter and two and a half inches long although housings of smaller diameter are quite common. A brake actuator which will be acceptable to bicycle manufacturers must be very simple and robust, have minimum drag when the brake is "off," involve no major alteration to the crankshaft housing and have a similar, if not identical, pedal crankshaft. In addition, it must be able to withstand "panic" stopping conditions without failure, such as might occur with a two hundred pound individual stamping on one of the pedals in the back-pedalling mode. Whilst an advantage of the coaster type of brake is the very large braking effort which can be developed by the user, it also raises the problem that the stresses developed in the actuator mechanism and applied to the brake mechanism, if not otherwise prevented, can also be very large if the user's entire weight is applied to one of the pedals in an attempt to obtain extra braking effort.
In the patents referred to above, proposals have been made to place the clutch mechanism either between the crank housing and one of the pedal cranks (as in Italian Pat. No. 456,997), or within the pedal crank arm (as in U.S. Pat. No. 1,488,714). In either case, the space available is very limited, and a non-standard crankshaft and/or crank arm is required. Moreover, the mechanism is subject to the accumulation of dirt and may be exposed to mechanical damage. Location within the crank housing itself (as in Italian Pat. No. 300,578) would thus be preferable were it not for the fact that in many cases the space between the crankshaft and the housing is extremely limited, thus making it difficult or impossible to house or assemble the structure shown in the Italian patent without cutting or slotting the housing to such an extent as to severely weaken it. The crankshaft housing is an integral part of the bicycle frame, and in order to obtain acceptance of a brake mechanism, it is desirable that no redesign of this component should be required, as would be the case for example in the structures of U.S. Pat. No. 2,940,563. Moreover, it should be possible to fabricate, assemble and maintan the brake mechanism without the use of esoteric or laborious techniques.
SUMMARY OF THE INVENTION
Objectives of the present invention are to provide a coaster type brake in which the brake actuating force is derived by a clutch connection from the pedal crankshaft, which can be constructed to withstand panic braking forces, which can be housed within most conventional types of pedal crankshaft housings, even those providing quite restricted clearance around the crankshaft, which is simple and inexpensive to manufacture and assemble, and which causes minimal drag during normal operation of the bicycle.
The invention improves upon a device for operating a brake of a pedal operated vehicle which device comprises a brake operating lever projecting through an opening in a pedal crankshaft housing of the vehicle, the lever being connected to a friction coupling which concentrically surrounds a pedal crankshaft within the housing, the coupling comprising two spring coils lightly embracing the crankshaft, the sense of winding of each spring coil, proceeding from a free end to a constrained end connected to the lever, being the same as that direction of rotation of the crankshaft producing forward movement of the vehicle, and the two spring coils being wound from a common length of wire which is looped at said constrained ends, the loop engaging the lever.
According to a first feature of the invention, the lever comprises an arm and a yoke encircling part of the circumference of the crankshaft, and is so dimensioned that in its plane of operation it has no dimension greater than the internal diameter of the pedal crankshaft housing but when the yoke engages the crankshaft, the arm of the lever projects through the opening in the housing beyond its outer surface.
According to a further feature of the invention, the spring coils are of a diameter such as just not to embrace the crankshaft, and at one end a further spring coil lightly embracing the crankshaft, the turns of which coil are of wire having a smaller cross section than that forming the turns of the first coils, overlaps and is attached to the diametrically outward side of the free end of each first coil so as to draw the latter in contact with the crank shaft housing when the second coil is placed under tension.
By these means, it is possible with the great majority of conventional crankshaft housings to assemble, without significant weakening of the housing, a clutch connection strong enough to withstand even panic breaking conditions, said clutch offering minimum drag on the pedal crankshaft during normal forward pedalling of the bicycle.
According to a further feature of the invention, the resultant thrust on the lever during brake operation, applied by the spring coils and a brake operator actuated by the lever is sustained through a thrust bearing: this enables a more compact assembly to be utilized, and facilitates assembly.
Further features of the invention will become apparent from the following description of preferred embodiments of the invention with reference to the accompanying drawings.
SHORT DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a vertical section through the crankshaft housing of a bicycle, longitudinally of the housing and transversely of the bicycle, showing a first embodiment of brake operator according to the invention;
FIG. 2 is a section on the line 2--2 in FIG. 1;
FIG. 3 is a section corresponding to FIG. 2, but with certain parts omitted for clarity and illustrating a modification of the embodiment of FIGS. 1 and 2;
FIG. 4 is a section corresponding to that of FIG. 3, illustrating a further modification;
FIGS. 5 and 6 each show fragmentary views of connections between the brake operator and a brake cable and a brake rod respectively;
FIG. 7 is a front (relative to the direction of travel of the bicycle) elevation of the spring coil assembly seen in FIGS. 1 and 2;
FIG. 8 is an end elevation of the spring coil assembly;
FIGS. 9-12 are diagrammatic elevations of bicycles illustrating the application of the invention to different types of rear wheel brake mechanism;
FIG. 13 is a section corresponding to that of FIG. 3, illustrating a modified embodiment of the invention suitable for application when the clearance between the crankshaft and the crankshaft housing is particularly limited;
FIG. 14 is a fragmentary plan view showing parts of the brake actuator of FIG. 13 assembled on the bicycle crankshaft;
FIG. 15 is a section corresponding to that of FIG. 1, illustrating a further embodiment of the invention;
FIG. 16 is a section through the embodiment of FIG. 15 on the line 16--16;
FIG. 17 is a view from the direction of the arrow 17 in FIG. 15 of the yoke used in that embodiment;
FIG. 18 is a view corresponding to that of FIG. 16, showing a modification of the yoke;
FIGS. 19 and 20 are end and plan views of a modified version of the yoke of FIG. 3;
FIGS. 21 and 22, and 23 and 24 are end and plan details of two arrangements for joining the larger and smaller spring coils used in the various embodiments of the invention;
FIG. 25 is a partial section through the crank housing of a bicycle illustrating a further embodiment of the invention; and
FIG. 26 is a fragmentary view from the direction of the arrow 26 in FIG. 25.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to the embodiment of FIGS. 1 and 2, the brake operator is accommodated between the pedal crankshaft 1 and the crankshaft housing 5 of a bicycle, the crankshaft being journalled within the housing by means of conventional ball race assemblies 14. All of these components may be of entirely conventional construction except that crankshafts of a waisted profile having a central portion of reduced diameter are not suitable: the central portion of the shaft between the races should have a cylindrical outer surface 2 of uniform diameter. The only non-standard feature of the crankshaft housing is the presence of a slot 8, described further below, in the bottom of the housing.
The major components of the brake operator are a lever comprising a yoke 24a and a lever arm 4a, and a spring coil assembly comprising spring coils 3 joined to one another by a connecting loop 15 which engages a complementary groove 16 formed in one arm of the yoke 24a. The lever arm 4a projects through the slot 8, and an apertured sheet metal shield 6 placed over the arm serves the dual purpose of preventing dirt from entering the housing through the slot 8 and helping to retain the loop 15 in the groove 16.
The construction of the spring coil assembly is best understood by references to FIGS. 7 and 8. The inner portions of the two coils 3 and the loop 15 are formed of a continuous length of square section steel wire. A square section is selected to provide maximum tensile strength in minimum bulk, but rectangular configurations other than square are possible if space requirements dictate a deeper but narrower coil. The outer portions 3a of the two coils are formed of wire of smaller cross section than the inner portions. In the embodiment shown, the cross sectional dimensions of the wire forming the outer portions are half those of the wire forming the inner portions. This enables a substantially larger number of turns to be accommodated in an assembly of the same width than would be possible if wire of the same section as that used for the inner turns was used throughout. The inside diameter of the turns in the outer portions is such that they lightly embrace the surface 2 of the crankshaft: the inside diameter of the turns on the inner portions is slightly larger so that they are normally just clear of the surface 2. The combination of the coil assembly is discussed further below in relation to the operation of the invention.
The lever comprising the yoke 24a and the arm 4a is dimensioned so that, as shown in chain-dotted lines in FIG. 2, it has no dimension exceeding the internal diameter of the crankshaft housing 5 and can thus be inserted into the housing until the arm 4a drops into the slot 8 without any necessity for the slot to be enlarged to accommodate oblique entry of the arm. Before the lever is so inserted, the shield 6 is placed over the arm 4a, the latter extending through loop 15 of the spring assembly. The three parts are then inserted into housing 5 and manipulated so that arm 4a drops through slot 8 and the loop 15 engages the groove 16, whereafter the crankshaft 1 is passed through the spring coils and the ball race assemblies 14 are assembled. Washers 7 may be provided to prevent any contact between the coils and the balls, or ball cages, if used, of the ball race assemblies.
In order to enable a longer lever arm to be utilized, the lever configuration may be as shown in FIG. 3, the yoke 24b being offset relative to the arm 4b. This arrangement permits a longer lever arm to be used without increasing the maximum dimension of the lever beyond the internal diameter of the crankshaft housing 5, as shown in chain-dotted lines in FIG. 3.
In FIG. 4, the yoke 24c is shown to include an integral strap so as to surround the crankshaft. In this case, the length of the lever arm 4c that can be accommodated within the crankshaft housing internal diameter is very limited, so a separate lever arm extension 4d of any required length is provided which can be attached to the projecting portion of the arm 4c after the latter is assembled into the crankshaft housing. As shown, the extension 4d is connected to the arm 4c by a dovetail joint and a locking pin 11, but other forms of connection could of course be utilized.
FIG. 5 illustrates a typical form of connection. between a lever arm such as 4a and a brake operating cable C terminating in a nipple N. The lever is formed with a clevis, one arm of which is provided with a slot S so that the cable may be introduced into the fork of the clevis when the nipple is introduced into its bore.
FIG. 6 illustrates a typical form of connection between a lever arm such as 4b and a brake operating rod R using a shackle K. This form of connection requires a greater projection of the lever arm from the crankshaft housing to provide the necessary clearance for the shackle.
FIGS. 9-12 illustrate different ways in which the brake actuator can be applied to a bicycle. In FIG. 9, the lever arm 4a of a lever as shown in FIG. 2 is attached to a cable 17 which passes through a flexible sheath 18 to a conventional caliper brake 19. Because of the direction of approach of the brake cable, the type of brake normally used on ladies' bicycles with hand operated rear brakes is appropriate, although it should be noted that it is an advantage of the present invention that the same brake assemblies can be used for bicycles both with and without cross-bars.
In FIG. 10, a caliper brake 20 is operated by a direct tension linkage which may be either a cable, or a rod 21 attached to the lever arm 4b of a lever as shown in FIG. 3 (or the extension 4d of a lever as shown in FIG. 4). In FIG. 11, a drum brake 22 of known type is applied to the rear wheel hub of the bicycle, and braking force is transmitted to a braking arm of the drum brake from the lever arm 4b (or 4d) by rods 23 and 30 and a step-out lever 25.
In FIG. 12, a brake disc 26 is applied to the rear wheel hub of the bicycle, and a brake caliper 27 is actuated by a cable 28 connected to the lever arm 4a and passing through a flexible sheath 29.
Considering now the operation of the embodiments so far described, normal forward pedalling of the bicycle will result in the crankshaft 1 rotating in an anticlockwise direction as seen in FIG. 2. The light engagement between the spring coil portion 3a and the surface 2 of the crankshaft will generate a reaction in the coils, which are restrained against rotation by the lever, tending to unwind the coils and thus reduce their engagement with the crankshaft and the resultant drag on the crankshaft. Since the portions 3a are in any event of fairly light gage wire, this drag will be slight in the first place. Upon back-pedalling, the drag of the coils will be transmitted to the brake rod or cable, and the resulting reaction will tend to wind up the coils, thus tightening their embrace of the crankshaft 2 and producing a positive feedback effect. As the force applied to the brake rod or cable increases, the inner portions of the coils 3 will also embrace the crankshaft, yet further enhancing the braking effort available. The tension in the wire forming the coils when these are in frictional engagement with the crankshaft will fall exponentially according to the distance from the loop 15 and thus the maximum tensions developed in the turns of the outer portions of the coils will always be small compared with the maximum tension developed in the inner coils. This enables the outer coils to be of greatly reduced cross section with the dual benefits of reducing the width of the coil for a given number of turns and reducing the drag on the crankshaft during normal forward pedalling. At the same time, the section of the wire used for the inner portions of the coils can be made large enough to withstand the tensions generated under panic braking conditions. With components of typical dimensions, and assuming worst-case conditions, the sum of the tensile loads sustained by both spring coils at their ends adjacent the loop 15 could be of the order of 5000 lbs. Such a load can be sustained if the wire is of quite ordinary spring steel, 0.110 inches square and heat treated to provide sufficient ultimate tensile strength. Only a small fraction of this load will be transmitted to the coil portions 3a, the actual proportion depending on the coefficient of static friction between the coil assembly and the crankshaft. Even if the coefficient of static friction is as low as 0.075, which is most improbable, and there are three turns in each inner portion of the coils, less than a quarter of the maximum tension will be applied to the coil portions 3a, and if the coefficient of static friction is a more probable 0.150, less than one sixteenth of the maximum tension will be applied to the coil portions 3a.
In order to sustain the tensions applied, the wire forming the portions 3a may be butt welded to the wire forming the remainder of the coils prior to coil winding and heat treatment, but other forms of connection may be preferred, provided that they will sustain the necessary loads and be sufficiently reliable. Some advantageous methods of joining the wires are discussed below with reference to FIGS. 21-24. Although the portions 3a have been shown as having a square section, a round section could be employed provided the space available permits the cross sectional area to be maintained. Moreover, although spring steel has been mentioned as a material for the spring coils, only a very small degree of resilience in the latter is in fact required. The tensile strength of the metal employed is more important than its yield strength since a small degree of plastic yielding can be sustained without failure of the clutch.
The yoke 24a, b or c should of course be sufficiently strong to sustain the loads applied to it by the coil assembly, but conventional bicycle brake equipment may not be strong enough to withstand the forces which could be applied through the lever arm under panic braking conditions. However, such forces can be limited by locating the forward end 8a of the slot 8 at a point such that it will act as a stop for the lever arm before the strain imposed on the brake linkage and brake reaches an excessive level. Should the stop 8a ever become operative under normal conditions, this indicates an immediate need for brake adjustment. The stop also prevents excessive forces being applied to the outer end of the lever arm, a particularly valuable feature when a lever arm extension 4d is being employed.
With certain types of brake, the high forces which can readily be developed by the brake operator of the invention are an advantage, as when a disc brake as shown in FIG. 12 is to be operated. Such disc brakes often require higher operating forces than can readily be developed by conventional hand brake operating levers.
The embodiments of the invention so far described are suitable for use with bicycles having crankshaft housings about one and a half inches external diameter and two and a half inches long, with a crankshaft about 13/16 inch in maximum diameter. Although these dimensions are typical, both larger and smaller housings are used, and with housings of smaller internal diameter, it may be found that the presence of the groove 16 in the yoke of the embodiments previously described will reduce the dimension Z (see FIG. 3) to such an extent that the yoke is seriously weakened. In the embodiment of FIGS. 13 and 14, the loop 15a of the spring coil assembly is taken around the root of the lever arm 4e, The reaction to tension in the spring coil assembly during braking will now tend to cause the yoke to rock away from the crankshaft, rather than being pulled against it as in the previous embodiments, and this problem is overcome by forming side flanges 31 on the yoke 24e which support portions of the first turn of each coil 3, resulting in tension in the coils generating forces holding the yoke against the crankshaft surface 2. The shield 6b is formed with side flanges 32 which act to prevent the coils 3 from slipping sideways off the flanges 31.
With this arrangement, it is possible to fit a brake actuator of adequate strength to withstand panic braking forces within a crankshaft housing having an outside diameter of only 13/8 inches, a wall thickness of about 3/32 inch and a crankshaft diameter of 13/16 inch.
The embodiment of FIGS. 15-17 represents a further approach to accommodating the brake mechanism within a housing of limited diameter, as well as facilitating assembly. The arrangements previously described necessitate installation of the yoke and spring in the crankshaft housing prior to installation of the crankshaft itself. This assembly procedure cannot be adopted where the crankshaft is forged in one piece with the pedal cranks, and also requires care to obtain and maintain the desired interrelationship of the various parts until they are locked in place by insertion of the crankshaft. The embodiment of FIGS. 15-17 permits the spring to be pre-assembled on the crankshaft before insertion of the latter and minimizes the free space required within the crankshaft housing to permit assembly, whilst maximizing the length of the operating lever arm obtainable relative to the overall yoke dimensions. In describing these embodiments, the same reference numerals will be used as in FIGS. 1 and 2 except where parts are significantly modified, and only those features will be described which are necessary to the understanding of these differences.
As compared with FIGS. 1 and 2, the main difference resides in the yoke 24f and its engagement with the bight portion 15 of the spring which passes around the entire yoke so that the bight portion engages the rear end 33 of the yoke. This means that when the brake is applied tension in the spring pulls the front end 34 of the yoke against the shield 6 which acts as a thrust bearing to transfer the load imposed on the yoke by the spring and the brake operator through the lever 4f to the crankshaft housing. The shield 6 should be of material such as bronze appropriate to perform this function as well as preventing dirt from entering the crankshaft housing. In order to maintain the bight portion 15 of the spring in contact with the yoke during forward pedalling of the bicycle, a tab 35 on the shield is bent up around the bight portion. This function may alternatively be performed by an extension 36 of the yoke as shown in FIG. 18.
In assembling the embodiments of FIGS. 16-18, the shield 6 is placed over the arm of the lever 4f and the assembly placed in the crankshaft housing so that the lever projects through the opening 8 in the crankshaft housing 5. The spring coil assembly is then positioned over the surface 2 of the crankshaft 1, which is inserted into the housing sufficiently eccentrically (see the broken lines in FIG. 16) for one half of the spring assembly to pass the yoke 24f. The crankshaft is then lowered so that the bight 15 of the spring assembly passes between the tab 35 and the end 33 of the yoke, or between the end 33 of the yoke and the extension 36, whereafter the bearing assemblies 14 can be installed. With this arrangement, the minimum clearance between the crankshaft surface 2 and the interior of the housing need be little more than double the thickness of the wire forming the spring portions 3, whilst the yoke 24f may be made short, thus minimizing the overall dimensions of the lever 4f. The arrangement may also be used where the crankshaft 1 and pedal cranks are forged in one piece.
FIGS. 19 and 20 show a stronger alternative to the yoke 24b shown in FIG. 3. The yoke 24b in FIG. 3 is weakened by the presence of groove 16. In the embodiment of FIGS. 19 and 20, the weakness introduced into the yoke 24g is compensated for by providing lateral flanges 37 which underlie the bight 15 of the spring.
FIGS. 21 to 24 illustrate two alternative methods of securing the spring portions 3a to the spring portions 3. In the arrangement of FIGS. 21 and 22, the wire forming the spring portion 3a is formed with a hammer end which is received in a complementary slot in the upper surface of the end of the wire forming spring portion 3 and held in place simply by its own spring action. This is an arrangement that is suitable when a single piece crank is used as the portions 3 and 3a of the clutch coil may be separately assembled onto shaft 1 and then the hammer heads of portion 3a sprung into the complementary slots of portion 3. The hammer end may be replaced with a straight end and complementary slot 39 as shown in FIGS. 23 and 24 with the fastening being done by brazing. The engagement of these fastening arrangements with the outer side of the wire 3 assists in drawing the latter into contact with the crankshaft during engagement of the brake, whilst the lapped nature of the joints makes them very strong.
The bight 15 of the spring assembly may be received in a groove on the radially inner surface of the yoke without the reaction from the spring and the brake actuator being sustained by the crankshaft housing 5. Such an arrangement is shown in FIGS. 25 and 26 and has the advantage of permitting simplified fabrication of the yoke 24h. A part ciruclar groove is formed near the front end 34 of the yoke in its radially inner surface by simple application of a trepanning cutter so as to leave a round pillar 40 which is engaged by the loop 15. The configuration causes the resultant of the reaction from the braking forces 41, 42 to be sustained by the crankshaft whilst greatly simplifying machining of the yoke. The groove is located so that the spring acts on the yoke at a point on the opposite side of the lever 4h from the direction of the braking force 42. | A coaster brake for a bicycle has a brake operating lever consisting of a yoke and integral arm coupled to the pedal crankshaft of the bicycle by a self-acting unidirectional friction clutch, formed by a coil spring embracing the crankshaft. In order to facilitate its insertion into the crankshaft housing, the lever has no dimension greater than the internal diameter of the housing. The spring has two portions, one on either side of the yoke, the wire forming the part of each portion nearer the yoke being of greater cross section than the part further from the yoke. The lever moves a brake actuating rod or cable actuating a wheel brake which may be of several different types. | 8 |
BACKGROUND AND SUMMARY
[0001] The invention relates to a frame-steered vehicle and to a method for controlling a frame-steered vehicle.
[0002] A fundamental problem in all vehicles with drive to multiple ground contact surfaces is how the driving force is distributed. It is desirable to control the speed of the wheels so that the wheel slip in the longitudinal direction is the same at all ground contact surfaces, since excessive wheel slip at individual ground contact surfaces is thereby prevented. The wheel slip is the scaled difference between the speed of the wheel at the ground contact surface and speed of the ground at the same point. Low tractive force at contact surfaces with low friction is automatically compensated for by increased tractive force at contact surfaces with high friction.
[0003] Given similar ground conditions, the coefficients of friction utilized will be approximately the same regardless of the prevailing vertical load at each ground contact surface. This means that the tractive force is automatically distributed in proportion to the vertical load, which gives optimum efficiency in transmitting force to the ground.
[0004] One easy way of producing the desired equality in longitudinal slip is to mechanically connect the driving of all wheels in the powertrain. Problems arise, however, when cornering. In this context the ground will move at different speeds at the various ground contact surfaces. When discussing the speed of the ground, it is herein intended the speed of the ground relative to the vehicle. The ground under the outer wheels moves at a higher speed than the corresponding inner wheels, since the outer wheels have a greater distance to cover in the same time as the inner wheels.
[0005] For the same reason the ground under the front wheels generally moves at a higher speed than under the rear wheels. In certain articulated vehicles, such as loaders, the drive to the front and rear axle is mechanically linked. The aim is to eliminate the problem of different speeds under the two axles by placing the steering joint midway between the front and rear axle, which when driving with a constant radius of curvature gives the same ground speed under both axles.
[0006] The rotational speeds are the same due to the mechanically linked drive. With superelevation of the stationary vehicle, however, which is a common working situation for loaders, the two axles will be drawn closer to one another, which mean that the ground under each axle moves in opposite directions. This results in slipping at the ground contact surfaces and loads in the powertrain that will reduce its service life. There is obviously also the outstanding inner/outer wheel problem.
[0007] In the majority of vehicles, such as four-wheel drive cars, trucks with 4×4 and 6×6 drive and articulated transport vehicles, the vehicle concepts are such that it is impossible to alleviate the front/rear axle problem through suitable locating of the steering joint.
[0008] In straight-line driving no losses are sustained, since the difference in rotational speed is zero. The problem of also distributing the tractive force when cornering is conventionally solved by dividing the torque in a specific ratio by means of a differential. The rotational speed is then controlled by the speed of the ground at the various contact surfaces and by the wheel slip. The fact that wheel slip is not controllable, however, is a disadvantage.
[0009] If the product of the vertical load and the ground friction does not correspond to the torque ratio in the differential, the wheel slip may increase uncontrollably, the wheel slip and the total tractive force transmitted is limited by the slipping ground contact surface.
[0010] The difficulty of the uncontrolled wheel slip is usually alleviated by various measures for braking the wheel slip, for example by using so-called differential locks. A dog clutch which mechanically locks the differential is the oldest and still perhaps the most common solution. The disadvantage is that the speed differential when cornering manifests itself as wheel slip at the actual ground contact surfaces. This produces great torque loads, which shortens powertrain service lives, increases losses and results in heavy tire wear.
[0011] Another solution aimed at limiting the slip in the case of differentials is to use the service brake to decrease torque at the slipping ground contact surface and thereby control the slip. The difference in rotational speed in braking corresponds to the vehicle speed, which can result in certain losses.
[0012] The brake torque may instead be applied inside the rotating differential, wherein the difference in rotational speed will correspond to the difference in the curve radius.
[0013] Mobile work machines are vehicles designed for and used in rough off-road surroundings where trucks or passenger cars are inoperative and would be damaged when exposed to these rough conditions. In order to facilitate off-road performance and ability to successfully handle slippery conditions a work machine can be equipped with two or more driven axles. However, when the axles are interlocked to improve traction, the drivability will suffer. In order to improve driveability, especially when turning, different speed of the wheel axles must be allowed.
[0014] An electronic traction control system for articulated work machines comprising two axles is described in U.S. Pat. No. 6,631,320 B1. In order to prevent tire slip in slippery conditions the automatic controlling algorithms calculate a desired speed of a wheel and use the brake in order to make the wheel to rotate with the desired speed.
[0015] WO 2007/035145 A1 discloses a method of controlling the speed of the wheels during cornering with an articulated hauler. The speed of the front wheels is allowed to be different from the wheels of the rear axles when the vehicle is cornering.
[0016] It is desirable to provide a frame-steered vehicle which allows for an improved control of a speed of the vehicle's ground engagement element axles. It is also desirable to provide an improved method for controlling a frame-steered vehicle.
[0017] According to an aspect of the present invention, a frame-steered vehicle is provided comprising a powertrain configured to provide drive torque to a transverse axle in a front vehicle section and at least one transverse axle in a rear vehicle section, wherein at least one longitudinal drive shaft is connected to the at least one transverse axle in the rear vehicle section. At least one controllable longitudinal clutch being variably adjustable between an engaged operational state and a disengaged operational state is arranged in the at least one longitudinal drive shaft.
[0018] The variation of the torque and/or rotational speed can be performed stepwise, infinitely, linearly or nonlinearly. It is also possible to perform the variation by combining two or more of those manners of variation, e.g. by using a different kind of variation manners in different torque ranges.
[0019] According to a favourable embodiment of the invention, the at least one controllable clutch is embodied to variably transmit torque and/or rotational speed in a predefined range of torque.
[0020] According to a favourable embodiment of the invention, the at least one controllable clutch is embodied to variably transmit infinitely torque and/or rotational speed in a predefined range of torque and/or rotational speed.
[0021] According to a favourable embodiment of the invention, a torque is variably controllable by the at least one controllable clutch.
[0022] According to a favourable embodiment of the invention, a rotational speed of the ground engagements elements is variably controllable by the at least one controllable clutch.
[0023] Favourably, the invention allows for an improved split of speed between the front and rear ground engagement elements. The operation of the vehicle is facilitated and can be more independent of the driver's skill. Today, in many cases drivers will drive the vehicle with the differential in the gear box locked all the time, which is very cost inefficient. Splitting the speed of the ground engagement elements can advantageously be provided automatically. The vehicle can provide superior performance, handling, driveability and off-road characteristics, particularly in slippery conditions. As a consequence of the functionality there is less mechanical stress in the entire powertrain which will vastly improve the service life of all related components in the vehicle. The need for maintenance can be reduced. The powertrain according to the invention is characterized by a low complexity and low cost compared to solutions known in the art. The at least one clutch can be operated actively, i.e. force is provided to close the at least one clutch, or passively, i.e. force is provided for releasing the clutch. A passive clutch is advantageous when using the drive axle for transmitting the torque from a parking brake to the ground engaging elements.
[0024] The propulsion power source of the vehicle can be a combustion engine, an electric machine or any device which can be used to provide propulsion power for a vehicle powertrain or any combination thereof.
[0025] Favourably, the at least one controllable clutch is embodied to variably transmit torque and/or rotational speed in a predefined range of torque and/or rotational speed. For instance, the torque and/or rotational speed can be varied stepwise. Alternatively, the torque and/or rotational speed can be varied continuously. The at least one clutch can be allowed to decrease the amount of transmitted torque and/or rotational speed compared to the torque and/or rotational speed delivered in certain predestined conditions.
[0026] Preferably, the at least one controllable clutch is embodied to variably transmit infinitely torque and/or rotational speed in a predefined range of torque and/or rotational speed. The distribution of torque and/or rotational speed can be performed with a particular sensible adjustment of the torque and/or rotational speed to the at least one ground engagement element axle.
[0027] According to a favourable embodiment, the at least one controllable clutch can be a mechanical clutch. The controllable clutch can comprise clutch plates, can be embodied as a friction clutch or can be any other type of clutch with variable torque transmission.
[0028] At least one controllable clutch can be arranged in a drive shaft connecting a front ground engagement element axle in the rear vehicle section to the front section. It is possible to distribute a balanced torque to the respective axles and thereby achieve an improved performance in off-road and slippery conditions and still preserve full driveability of the vehicle.
[0029] The balanced torque distribution and performance can also be improved if at least one clutch can be arranged in the drive shaft connecting a front ground engagement element axle in the rear vehicle section to a rear ground engagement element axle in the rear vehicle section. According to a favourable embodiment, at least one clutch is arranged in the drive shaft connecting the front ground engagement element axle in the rear vehicle section to the front section as well as in the drive shaft connecting the front ground engagement element axle in the rear vehicle section to the rear ground engagement element axle in the rear vehicle section.
[0030] Preferably, a monitor device can be connected to the at least one clutch for monitoring torque and/or rotational speed transmitted by the at least clutch.
[0031] Favourably, a control device can be provided to automatically control the at least one clutch. The control device can be a separate unit or can be integrated with the monitor device for monitoring torque and/or rotational speed transmitted by the at least clutch.
[0032] Alternatively, a manual device can be provided to manually control the at least one clutch. The driver can choose the amount of torque and/or rotational speed transmitted by the at least one clutch.
[0033] According to another aspect of the present invention, a method is provided for controlling a frame-steered vehicle, which comprises a powertrain configured to provide drive torque to a transverse axle in a front vehicle section and at least one transverse axle in a rear vehicle section, wherein at least one longitudinal drive shaft is connected to the at least one transverse axle in the rear vehicle section. The method comprises the step of variably adjusting at least one controllable longitudinal clutch between an engaged operational state and a disengaged operational state in order to variably transmit torque and/or rotational speed to said axles.
[0034] Favourably, the longitudinal slip of the ground engagement elements can be reduced or avoided and stress in the drive train can be reduced. The lifetime of components in the drive train as well as of the ground engagement elements is improved due to reduced stress-induced wear.
[0035] Preferably, the at least one controllable clutch can be controlled depending on the steering angle.
[0036] Preferably, the at least one controllable clutch can be controlled depending on at least one of axle speed, vehicle speed, tire slip, power source load, transported load of the vehicle, inclination angle.
[0037] The at least one clutch can be controlled automatically or, alternatively, can be controlled manually.
[0038] The invention can be applied to wheel-borne vehicles, track-borne vehicles and vehicles running on rails. Primarily wheel-borne vehicles are intended. The invention is specifically directed to mobile frame-steered work machines, such as articulated haulers, wheel loaders etc. The invention is particularly applicable in vehicles with a multitude of driven axles and will below be described for a frame-steered articulated hauler for the purpose of exemplification. The invention is primarily intended for vehicles used off-road in rough conditions. A fundamental problem for all vehicles with drive at a number of ground contact points is how the driving power is distributed. Advantageously the rotational speeds of the ground engagement elements can be controlled so that the slip in the longitudinal direction is the same at all ground contact points. Favourably, excessive slip at individual ground contact points can thus be prevented.
[0039] Further, when a peak torque, particularly an overload, is detected somewhere in the powertrain, the at least one controllable clutch can be used to avoid harmful load levels on powertrain components. Favourably, when a torque peak is detected, one could use this signal to limit the output torque of the power source of the vehicle.
[0040] The at least one controllable clutch can be controlled in a manner so that propulsion is transmitted to the front axle only, which is applicable in certain driving conditions where front axle drive is sufficient for the task to be performed. This can be advantageous for a reduced fuel consumption in such cases.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The present invention may best be understood from the following detailed description of the embodiments, but not restricted to the embodiments, wherein is shown:
[0042] FIG. 1 a side view of a preferred vehicle according to the invention, embodied as an articulated hauler;
[0043] FIG. 2 a top view of the articulated hauler of FIG. 1 ;
[0044] FIG. 3 a characteristic curve displaying a permissible area for control of rotational speed versus a steering angle; and
[0045] FIG. 4 a , 4 b a preferred powertrain of the articulated hauler of FIGS. 1 and 2 exhibiting two clutches in drive shafts ( FIG. 4 a ) and a schematic sketch of the powertrain ( FIG. 4 b ).
DETAILED DESCRIPTION
[0046] In the drawings, equal or similar elements are referred to by equal reference numerals. The drawings are merely schematic representations, not intended to portray specific parameters of the invention. Moreover, the drawings are intended to depict only typical embodiments of the invention and therefore should not be considered as limiting the scope of the invention.
[0047] FIG. 1 shows a vehicle 10 preferably embodied as a frame-steered articulated hauler, also called dumper, in a side view according to the invention. By way of example, the ground engagement elements are embodied as wheels.
[0048] The vehicle 10 embodied as a frame-steered articulated hauler comprises a front vehicle section 12 comprising a front frame 14 , a front wheel axle 16 as front ground engagement axle 16 in the front vehicle section 12 and a cab 18 for a driver. The vehicle 10 also comprises a rear vehicle section 20 comprising a rear frame 22 , a front wheel axle 24 , a rear wheel axle 26 as front and rear ground engagement element axles in the rear vehicle section 20 and a tillable platform body 28 .
[0049] The front and rear wheel axles 24 , 26 of the rear vehicle section 20 are connected to the rear frame 22 via a bogie arrangement (not shown), and will below be referred to as front wheel axle 24 (ground engagement element axle 24 ) and rear wheel axle 26 (ground engagement element axle 26 ).
[0050] Each of the front wheel axles 16 , the front wheel axle 24 and the rear wheel axle 26 comprises pairwise left and right ground engagement elements 100 , 102 , 104 embodied as wheels. In the side view, only the left ground engagement elements 100 a, 102 a, 104 a are depicted. Generally, the term “ground engagement elements” can include wheels, caterpillar tracks etc.
[0051] The front frame 14 is connected to the rear frame 22 via a first rotary joint 46 which allows the front frame 14 and the rear frame 22 to be rotated relative to one another about a vertical axis 60 for steering (turning) the vehicle 10 . A pair of hydraulic cylinders 52 is arranged on respective sides of the rotary joint 46 for steering the vehicle 10 . The hydraulic cylinders are controlled by the driver of the vehicle via a wheel and/or a joystick (not shown).
[0052] A second rotary joint 54 is adapted in order to allow the front frame 14 and the rear frame 22 to be rotated relative to one another about an imaginary longitudinal axis, that is to say an axis which extends in the longitudinal direction of the vehicle 10 .
[0053] The platform body 28 is connected to the rear frame 22 via an articulation 58 , see FIG. 4 a , on a rear portion of the rear frame 22 . A pair of tilting cylinders 56 is connected with a first end to the rear frame 22 and connected with a second end to the platform body 28 . The tilting cylinders 56 are positioned one on each side of the central axis of the vehicle 10 embodied as a frame-steered articulated hauler in its longitudinal direction. The platform body 28 is therefore tilted/tipped in relation to the rear frame 22 on activation of the tilting cylinders 56 .
[0054] FIG. 2 shows a top view of the vehicle 10 of FIG. 1 . The two front and rear sections 12 , 20 of the vehicle 10 are connected by way of a vertical articulated shaft 46 (rotary joint 46 ). The front and rear sections 12 , 20 of the vehicle 10 are also connected to one another in a known manner so that they can pivot about a horizontal articulated shaft (not shown), so that the front and rear sections 12 , 20 can be rotated in relation to one another about the longitudinal axis of the vehicle 10 . Hydraulic cylinders (see FIG. 1 ), which are arranged on either side of the articulated shaft, are used for steering the vehicle 10 when cornering, the front section 12 of the vehicle 10 being angled about the vertical articulated shaft 46 .
[0055] According to the state of the art, the drive torque delivered by the vehicle engine is transmitted to the first wheel axle 24 arranged on the rear section 20 of the vehicle 10 by way of a mechanical transmission comprising a first propeller shaft, which connects the vehicle gearbox to the differential of the wheel axle 24 . A second propeller shaft is arranged between the first wheel axle 24 and a further wheel axle 26 arranged on the rear section 20 , for transmission of the drive torque delivered by the engine. Each of the axles 24 , 26 is provided with wheels 102 a , 102 b, 104 a, 104 b. The front section 12 of the vehicle 10 is provided with a wheel axle 16 having ground engagement elements 100 a, 100 b.
[0056] Since the distance between each wheel axle 24 , 26 and axle 16 and the vertical shaft 46 varies greatly, the axles 24 , 26 and 16 will follow essentially different turning radius R 1 , R 2 when cornering.
[0057] Thus the axles 24 , 26 on the rear section 20 of the vehicle 10 follow the turning radius R 1 , while the axle 16 on the front section 12 of the vehicle 10 follows the turning radius R 2 . Due to the fact that the turning radius R 2 is substantially larger than the turning radius R 1 , the ground engagement elements 100 a, 100 b must cover a significantly longer distance than the ground engagement elements 102 a, 102 b, 104 a, 104 b on rear section 20 of the vehicle 10 . In order to prevent these differences giving rise to torque load in the power transmission from the engine to the individual ground engagement elements 100 a, 100 b, 102 a, 102 b, 104 a, 104 b, there is a need for an individual adjustment of the rotational speed on each axle 16 , 24 , 26 .
[0058] The different distances and radii can cause stress inside the drive train. For instance, the distance a between the centre 45 of the axle 16 and the rotary joint 46 is smaller than the distance b between the rotary joint 46 and the centre 47 of the axle 24 .
[0059] FIG. 3 illustrates a characteristic curve displaying a permissible area for control of rotational speed versus a steering angle φ of the vehicle 10 displayed in FIGS. 1 and 2 . The permissible area is enclosed between the lower and the upper curve. The higher the steering angle φ, the more deviation of the rotational speed occurs.
[0060] FIGS. 4 a and 4 b show diagrammatically the powertrain of the vehicle 10 embodied as a frame-steered articulated hauler. Generally, the term “powertrain” means the entire power transmission system from the power source of the vehicle to the ground engagement elements. The powertrain therefore includes the power source, clutch, gearbox (and any transfer gearbox present), propeller shaft (or propeller shafts), transverse drive shafts etc. Hydraulic, electric and other drive systems are also included within the term powertrain.
[0061] A propulsion power source 70 in the form of an internal combustion engine, in this case a diesel engine, is adapted for propulsion of the vehicle 10 . The powertrain comprises a main gearbox 30 in the form of an automatic gearbox, which is operationally connected to an output shaft from the power source 70 . By way of example, the main gearbox 30 has six forward gears and two reverse gears. The powertrain also comprises a transfer gearbox 32 for distributing driving power between the front axle 16 and the two wheel axles 24 , 26 .
[0062] A first, second and third drive shaft 34 , 36 , 38 (propeller shafts) extend in the longitudinal direction of the vehicle and are each operationally connected to the transfer gearbox 32 (which is also called a distribution gearbox or an intermediate gearbox) and a central gear 40 , 42 , 44 in each of the wheel axles 16 , 24 , 26 . A pair of transverse drive shafts (stick axles) extends in opposite directions from the respective central gear. Each of the transverse drive shafts drives one of said wheels.
[0063] A first clutch 80 is arranged in the drive shaft 36 connecting the transfer gearbox 32 to the front wheel axle 26 in the rear vehicle section 20 . A second clutch 82 is arranged in the drive shaft 38 connecting the front wheel axle 24 in the rear vehicle section 20 to the rear wheel axle 26 in the rear vehicle section 20 .
[0064] The clutches 80 , 82 can transmit torque in a predefined range of torque depending on predetermined operation conditions of the vehicle 10 . Preferably, the clutches 80 , 82 are mechanical clutches and can transmit torque infinitely continuous between 0% and 100% of the torque applied to the clutch input.
[0065] A monitor device 90 is connected to the two clutches 80 and 82 for monitoring torque transmitted by the clutches 80 and 82 . Preferably, a rotational speed sensor and/or a torque sensor are arranged before and after each of the clutches 80 and 82 . The signals of the sensors are transmitted to the torque monitor system 90 .
[0066] The automatic control algorithm, particularly in the ECU (electronic control device) can secure all wheel traction and prevent tire slip in slippery conditions by distributing the torque infinitely to all wheels depending on at least the steering angle and/or inclination angle of the vehicle 10 and/or tire slip and/or axle speed and/or power source load and/or transported load of the vehicle 10 and/or steering angle φ (see FIG. 3 ) or other signals or conditions.
[0067] A manual device (not shown), such as a lever or an adjusting knob, can be provided to allow the driver to manually control the clutches 80 and 82 . Alternatively or additionally, a control device can be provided to automatically control the clutches 80 and 82 .
[0068] The invention favourably allows for better driveability as the rotational speed of the rear ground engagement elements, e.g. wheels, can he reduced and understeering can he avoided. A longer life of the powertrain components can be achieved. Further, by reducing or avoiding the slip of the ground engagement elements, wear on the ground engagement elements is reduced. For example, by reducing tire wear (in case of ground engagement elements embodied as wheels) unnecessary maintenance breaks and costs for replacing damaged tires can be saved.
[0069] An additional differential unit in the wheel axles for realization of different rotational speed in different wheel axles can be renounced. A longitudinal differential unit in the transfer gear box for realization of different rotational speed in different wheel axles can be renounced. Favourably, the controllable clutch can replace any dog clutch of an automatic traction control (ATC) unit comprising a dog clutch as well as any longitudinal differential unit coupled to this ATC. An overload protection can be provided so that powertrain components behind the one or more clutches in the wheel axles can be compact and not oversized. | A frame-steered vehicle includes a powertrain configured to provide drive torque to a transverse axle in a front vehicle section and at least one transverse axle in a rear vehicle section. At least one longitudinal drive shaft is connected to the at least one transverse axle in the rear vehicle section. At least one controllable longitudinal clutch is variably adjustable between an engaged operational state and a disengaged operational state is arranged in the at least one longitudinal drive shaft. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to epoxidized polyamide wet strength resins containing lecithin and their use in paper and molded pulp products made of cellulose fibers such as wood pulp.
2. Background and the Prior Art
In the manufacture of wet strength paper and molded pulp products, a wet strength resin is added to the pulp slurry. Wet strength resins are typically of the epoxidized polyamide, urea formaldehyde or melamine formaldehyde types. These resins provide cross-linking to impart wet strength required by various paper and molded pulp products.
During the paper or molded pulp drying process, polymers such as those of melamine formaldehyde and urea formaldehyde may become a health hazard due to release of formaldehyde. Also, the epoxidized polyamide polymers as well as the melamine formaldehyde and urea formaldehyde polymers can at times stick to hot dryer surfaces. This problem is particularly acute with the epoxidized polyamide wet strength resins in the making of molded pulp products. Thus, in the manufacture of molded pulp products, wherein melamine formaldehyde wet strength resin is used, we have found that sticking is not a problem. However, the use of epoxidized polyamide in place of the melamine formaldehyde caused undesirable sticking of resin and pulp to the drier and furthermore the internal bond strength of the dried molded pulp product was weak. Also, it appears that urea formaldehyde wet strength resins are also not as susceptible to sticking to heated drier surfaces as with the epoxidized polyamides.
The application of various release agents to paper making dryer surfaces as well as to heated platens in pressing glue coated wood particles to make panels is well known for preventing sticking of resin to such surfaces. However, such application of a surface lubricant means the addition of another process step with the consequent increase in production time as well as an additional cost due to the amount of lubricant needed. Also, for release of molded pulp products from molds, additional difficulties are encountered in application of release agents due to the contoured and curvilinear surfaces of such molds.
In the making of wood based panels such as particleboard, by using melamine formaldehyde glues, press operators have applied an emulsion of five parts of lecithin in four parts aqua ammonia of 26 Baume and 91 parts of water as a release agent on the press surfaces. Such release agent is sold by Borden, Inc. under the designator PC-803L.
U.S. Pat. No. 4,076,896 of Feb. 28, 1978, shows the manufacture of laminates by impregnating paper with a melamine formaldehyde glue containing lecithin wherein the lecithin increases the release characteristics of the resin when pressing out a panel. Japanese patent publication JP55-139430 to Matsushita Elec. Works relates to the manufacture of a laminated sheet which includes impregnating paper or cloth with a thermosetting resin containing lecithin wherein the resins are said to include phenol resins, epoxy resins, polyester resins and melamine resins. U.S. Pat. No. 4,267,240 of May 12, 1981 to Formica Corp. relates to a release sheet comprising a web of paper having one side coated with various materials including lecithin.
The Kamikaseta et al U.S. Pat. No. 4,634,727 of Jan. 6, 1987 relates to a polyvinyl acetate emulsion adhesive for bonding wood and other porous substances wherein lecithin is added directly to the adhesive emulsion or the lecithin is first emulsified with aqueous ammonia before addition to the adhesive. In this 727 patent, the lecithin is said to assist in release of the adhesive from the press platens and increases the bonding strength of the adhesive. The 727 patent states that various additional polymers may be added to the lecithin containing polyvinylacetate such as urea resin, phenol formaldehyde resin and melamine resin.
Japanese patent publication No., JP 1045894 to OJI Paper KK relates to the manufacture of paper which is said to have improved releasability by having release agents added to a layer of paper wherein the release agents include lecithin. Japanese Patent publication No. JP 88-057206 to Kobe relates to the production of a laminate by preimpregnating a paper substrate with a solution containing a surfactant and a cure accelerator for a phenolic resin varnish wherein lecithin is referred to as a cure accelerator. U.S. Pat. Nos. 1,977,251 to Stallmann of Oct. 16, 1934 and 3,947,383 to Baggett of Mar. 30, 1976 describe reaction products of ammonia and epichlorohydrin for use as a paper wet strength resin additives.
SUMMARY OF THE INVENTION
We have now found that the addition of lecithin in epoxidized polyamide wet strength resins eliminates the sticking problem encountered on the heated driers in the manufacture of paper and particularly in the manufacture of molded pulp products. The lecithin is preferably dispersed in an emulsifying or dispersing agent prior to its incorporation in the epoxidized polyamide. The epoxidized polyamide containing lecithin is added to the pulp slurry prior to forming of the molded product or paper on the wire mesh. Alternatively, each of the epoxidized polyamide and lecithin can be added separately to the aqueous pulp slurry. The addition of lecithin also improves the internal bonding of pulp in paper and molded pulp products which utilize epoxidized polyamide wet strength resins.
DESCRIPTION OF THE INVENTION
The epoxidized polyamide wet strength resins are water soluble cationic thermosetting resins. They are generally sold as aqueous solutions containing from about 10% to 35% by weight of resin solids, i.e., about 10% 35% by weight of the epoxidized polyamide. Curing of such polyamides in paper and molded pulp products on hot drying surfaces increases the wet strength of the paper or molded pulp product. Generally, sufficient wet strength resin is added so that the wet strength of the paper or molded pulp product is greater than about 15 percent of its dry strength. Wet strength is the load required to break the paper when completely wet with water. The strength measurements may include wet tensile, wet mullens (burst), and wet tear. Paper and other pulp products manufactured without any additives do not have wet strength. By the term paper, we mean to include paperboards, towling, tissue, food board, linerboard and corrugating medium. By the term molded pulp products, we mean to also include molded pulp/textile containing products. Molded pulp products are contoured products made of pulp such as egg packaging items, food trays, plates, flower pots, bottle protectors, and the like. Illustrative of molded pulp products which contain textiles, there can be mentioned contoured products such as the interior part of automobile doors, panels, etc. In contoured products, the contour is a part of the permanent shape of the article involved and such products often have surfaces which are that of compound curves.
Epoxidized polyamide wet strength resins are well known materials and their composition and method of preparation are amply described in the literature such as in the following U.S. Pat. Nos. 3,565,754; 3,733,290; 3,793,279; 3,887,510, 3,914,155; and 4,501,862. As can be seen from the above references, amides which may be reacted with epihalohydrins, e.g., epichlorohydrin, to form the polyamide wet strength resin are also referred to as polyaminopolyamides. The polyaminopolyamides are generally prepared by reacting polycarboxylic acids, or their esters with polyalkylenepolyamines such as those having two primary amine groups and at least one secondary or tertiary amine group. The polycarboxylic acids or esters thereof can be aromatic or aliphatic. The acids are generally C 2 to C 20 saturated aliphatic dicarboxylic acids and the esters can be formed by reacting such acids with alkanols having from 1 to about 4 carbon atoms. The polyaminopolyamides are then epoxidized to form the epoxidized polyamide wet strength resins. Some of the epoxidized polyamide wet strength resins are modified with other reactants or the starting materials for such resins are modified. Thus, the polyaminopolyamide can be reacted with other compounds such as urea or formaldehyde or the acids can be substituted such as in the case of nitrilotriacetic acid.
A preferred class of epoxidized polyamide wet strength resins are disclosed in U.S. Pat. No. 3,887,510 which issued to Chan et al on Jun. 3, 1975. In the Chan et al patent, dicarboxylic diesters derived from C 3 to C 6 saturated aliphatic dicarboxylic acids and respectively C 1 to C 3 saturated aliphatic monohydric alcohols are reacted with a polyalkylenepolyamine to prepare the polyaminopolyamide. As to the acids from which the esters are derived, there can be mentioned malonic, succinic, glutaric and adipic acids. The alcohols can be singly or in combination, methanol, ethanol, n-propanol or isopropanol. Methyl esters such as dimethyladipate and dimethylgluterate are the preferred esters.
Illustrative of suitable polyalkylenepolyamines of the Chan et al patent, there can be mentioned: diethylenetriamine; triethylenetetramine; tetraethylenepentamine; dipropylenetriamine; 4-methyldiethylenetriamine; 5-methyldipropylenetriamine; 4, 7 dialkyltriethylenetetramine; and dihexylenetriamine. The polyalkylenepolyamines of the Chan et al patent have the generic formula:
H 2 NC n H 2n (NRC n H 2n ) x NH 2 either C 1 to C 4 alkyl or hydrogen, x can vary from 1 to about 5 and n can vary from about 2 to 6. In some cases however it is desirable to increase the spacing of secondary amine groups and this can be done by substituting a diamine such as ethylenediamine, hexamethylenediamine and the like for a portion of the polyalkylenepolyamine. A preferred epoxidized polyamide is that made from the polyamide resulting from reaction of dimethyl gluterate and diethylene triamine.
The incorporation of lecithin in a pulp slurry containing epoxidized polyamide inhibits sticking of the wet strength resin or pulp fibers to the surfaces of the driers. Furthermore, such use of lecithin increases the bonding strength of the pulp to itself or through the action of the wet strength resin. The quantity of lecithin used in the aqueous pulp slurry to obtain the advantages of this invention varies over a broad range such as from about 0.1 percent to 15 percent or more by weight of lecithin based on the weight of the wet strength resin solids, i.e., the epoxidized polyamide. Preferably the quantity of lecithin in the pulp slurry is from about 2 to about 10 percent by weight of lecithin based on the weight of the resin solids.
A preferred composition of this invention is a stable concentrate of the wet strength resin and lecithin which can be added to the aqueous pulp slurry. Such composition contains at least 61 percent of water and comprises an aqueous solution of epoxidized polyamide wet strength resin having a solids content of from about 8 to 35 percent by weight of said composition, from about 0.1 percent to 12 percent by weight of lecithin based on the weight of said resin solids and from about 61 percent to about 92 percent by weight of water and wherein said composition has a pH of about 3 to 5. Preferably, such composition contains from about 10 percent to 30 percent by weight of said resin solids and 6 to 10 percent lecithin, based on said resin solids and 67 to about 89 percent of water. These concentrates can also contain small quantities, e.g., up to about 2 or 5% by weight based on the weight of resin solids, of various solvents, emulsifiers or dispersing agents for the lecithin.
The lecithin can be added to the aqueous pulp slurry directly or it can first be added to the wet strength resin which is subsequently added to the aqueous pulp slurry. Preferably the lecithin is incorporated in the wet strength resin, as the above described concentrate, before addition of these chemicals to the pulp slurry. Lecithin is not soluble in water. Therefor it is preferred that a solution, emulsion or dispersion of the lecithin be used. Alternatively, hydrolized lecithin can be employed or the lecithin itself can be intimately dispersed into the wet strength resin or pulp slurry such as by mixing. A preferred way for getting the lecithin into the wet strength resin or directly into the aqueous pulp slurry is by first emulsifying the lecithin in aqueous ammonia water such as an emulsion containing 5 parts lecithin, 4 parts aqua ammonia of 26 Baume and 91 parts of water.
The molded pulp products and various paper products of this invention are made by conventional techniques except that a small quantity of lecithin is used together with the epoxidized polyamide wet strength resin in the aqueous pulp slurry in making such products. Illustratively, the molded pulp products can be made by depositing pulp fibers from a slurry on to a foraminous, e.g., wire mesh, mold. There can be single or multiple molds which can be fixed or as part of a conveyer so that a continuous operation can be realized. Molds on a conveyer often involve a rotating cylinder with suitable porting connections. Wet preforms from the initial mold are often pressed to a desired thickness and then dried under restraint between matched heated dies or in an oven. The drying process will vary depending upon the density of the finished product but can vary from about 1 to about 3 minutes. The thickness of the molded pulp products can vary over a wide range such as that of about 0.1 inch to about 0.4 inch.
Briefly, in the production of various papers, including paperboard, the paper furnish, after stock preparation and proper dilution, is usually sent to the paper machine through one or more screens or other devices to remove dirt and fiber bundies. It then proceeds to a flow spreader to provide a uniform flowing stream of the width of the machine. The flow spreader discharges the slurry into a headbox, where turbulence is controlled, fiber flocculation is minimized, and the proper head is provided to cause the slurry to flow out through the slice and onto a moving wire at the proper velocity. The sheet leaving the "wet end" is pressed to remove additional water by mechanical means. At this stage, the wet sheet has reached the point where further water removal by mechanical means is not feasible and evaporative drying must be employed. The evaporative driers are generally steam heated cylinders, with alternate sides of the wet paper exposed to the hot surface as the sheet passes from cylinder to cylinder.
During the manufacture of paper or molded pulp products, several additives are introduced at the "wet end" of the process, i.e., in the pulp slurry, to give the finished products the required physical properties. One of these additives is the wet strength resin. During drying on hot surfaces, the wet end additives, including the wet strength resins, may cause residual build-up on heated dryer surfaces. This build-up will cause the molded product or paper to stick to the dryer causing dryer wrap or breaks in the case of cylinder dryers or the need for manual removal of the contoured molded product in the case of molded pulp products. The use of lecithin as set forth in this invention overcomes or minimizes these sticking or breaking problems. Additionally, the lecithin increases the strength of internal bonding in paper and molded pulp products. The percentage of dry pulp solids in the aqueous pulp slurry vary over a wide range but, initially, prior to the draining of water are on the order of about 0.5 to 5 percent of the slurry. The quantity of epoxidized polyamide to dry pulp solids in the slurry will generally vary from about 0.1% to about 5%.
In order that those skilled in the art may more fully understand the inventive concept presented herein, the following examples are set forth in the appended claims. All parts and percentages are by weight unless otherwise stated.
EXAMPLE 1
Epoxidized polyamide wet strength resin, namely Cascamid C-20, was added to a pulp slurry at a rate of 2.25% (45 pounds of wet strength resin solids per ton of dry pulp solids) to form a 0.65 gm/cm 3 molded pulp sheet. Cascamid C-20 is an aqueous solution of wet strength resin sold by Borden, Inc., having 20 parts of epoxidized polyamide in 80 parts of water and wherein the polyamide, prior to epoxidation is the reaction product of dimethylgluterate and diethylenetriamine. The sheets were formed in a deckel box, pressed to a thickness of 2.5 mm and dried on matching die driers at 530° F., for 2.5 minutes. Several of the sheets were observed to stick to the upper die drier as the lower one descended. The sheets also showed evidence of picking which was determined through visual observation and roughness of test specimens. In an attempt to cut specimens for testing, the sheet broke across the center internally at a place intermediate its top and bottom surfaces due to internal bond failure resulting from what was attributed to improper cure of resin and/or moisture escaping from the center.
EXAMPLE 2
Laboratory handsheets were prepared as in Example 1 above except that the resin addition level was reduced to 0.5% (10 pounds of wet strength resin solids per ton of dry pulp solids) and a contoured die disc was not used. Test samples were placed between heated press platens for drying. Upon lowering the lower plate, the specimens stuck to the upper plate and again showed bonding failure through the center of the specimen, i.e., internally in a plane intermediate its top and bottom surfaces.
EXAMPLE 3
Laboratory handsheets were prepared as in Example 2 above except that 0.1% of PC-803-L (by weight, based on the weight of resin solids in C-20) and 0.5% Cascamid C-20 (by weight, based on the weight of dry pulp solids) were each added separately to the slurry. Handsheets did not show signs of sticking or internal failure on cutting. PC-803-L is an aqueous emulsion of lecithin in ammonia. The aqueous emulsion consists of 5 parts of lecithin in 4 parts of ammonia aqua of 26 Baume and 91 parts of water and is sold by Borden, Inc. as a protective coating to be applied to platen surfaces used to make particleboard with melamine formaldehyde glues.
EXAMPLE 4
Laboratory handsheets were prepared as in Example 2 above except that 0.5% Cascamid C-20 (by weight, based on the weight of dry pulp solids) mixed with 0.1% of PC-103-L (by weight, based on the weight of wet strength resin solids) before addition to the slurry. The sheets did not show signs of sticking or internal failure. Cascamid C-20 is an aqueous solution of wet strength resin sold by Borden, Inc. having 20 parts of epoxidized polyamid in 80 parts of water and wherein the polyamide, prior to epoxidation is the reaction product of dimethylgluterate and diethylenetriamine. PC-103-L is a product sold by Borden, Inc. and referred to as a protective coating. It is composed of an aqueous emulsion of 5 parts lecithin in 4 parts of ammonia aqua of 26 Baume and 91 parts of water.
EXAMPLE 5
A mixture of Cascamid C-20 (69.32%) at 20% solids, 29.64% of PC-803L and 1.04% hydrochloric acid was applied to pulp/synthetic pulp slurry at 0.5% (10 pounds per ton) as in 1 above showed no signs of sticking nor of internal failure and had satisfactory properties with respect to percent swell, burst flexural strength and modules of elasticity. This was 10.69% lecithin by weight based on weight of the resin solids.
EXAMPLE 6
Specimens were prepared as in Example 5 above except that the resin was applied at 1% (20 pounds of resin solids per ton of dry pulp solids) and the PC-803L and hydrochloric acid were not used. The sheets stuck to drier surface and showed signs of internal failure.
EXAMPLE 7
Specimens were prepared as in Example 1 above except that the resin mixture was 69.32%, Cascamid C-25 at 25% solids, 29.64% of PC-803L and 1.04% hydrochloric acid. Specimens showed no signs of sticking or internal failure. The amount of lecithin in the PC-803L amounted to 8.6% of lecithin on the resin solids. | A composition comprising epoxidized polyamide wet strength resin and lecithin. The composition provides wet strength to paper and molded pulp products and at the same time increases the internal bonding of the paper or molded pulp products. | 3 |
[0001] This application claims the benefit of U.S. Provisional Application No. 60/269,620, filed Feb. 15, 2001.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to machine tools, and more specifically, to an automated tool storage and handling device.
SUMMARY OF THE INVENTION
[0003] The present invention is directed to a hydrostatic tool system including a tool assembly having a hydrostatic tool holder for holding a rotating tool, for example a machine or cutting tool. The hydrostatic tool system may also include a tool storage system, a tool transport system and a tool drive system. The hydrostatic tool system may also include an hydraulic coupler for hydraulically connecting the hydrostatic tool holder to a pressurizing or depressurizing source. The hydrostatic tool system may also include a system controller.
[0004] Each tool assembly includes a hydrostatic tool holder having an inner sleeve nested within an outer sleeve which cooperate in such a manner as to form a gap between the outer circumferential surface of the inner sleeve and the inner circumferential surface of the outer sleeve. A chamber is defined by the gap between the inner and outer sleeves, the nesting configuration of the bulkheads and flanges of the inner and outer sleeves and the nesting configuration of the flanges of the inner and outer sleeves. The inner sleeve includes an inner bore configured to concentrically engage a machine spindle. The outer sleeve includes an outer circumferential surface configured to concentrically engage a rotatable tool. In one preferred embodiment of the invention, the hydrostatic tool holder outer sleeve includes an hydraulic fitting which permits the introduction, pressurization and extraction of the hydraulic fluid into the chamber between the inner sleeve and the outer sleeve. The hydraulic fitting may be configured as an hydraulic test point including a poppet valve. The hydraulic test point is configured to releasably engage and hydraulically communicate with an hydraulic coupler which, in turn, communicates hydraulically with a pressurized source of hydraulic fluid. The inner and outer sleeves of the hydrostatic tool holder deflect slightly under hydrostatic fluid pressure to engage both the spindle and the rotating tool.
[0005] The hydrostatic tool holder also includes a collar which is configured for gripping engagement by a pair of articulated clamping arms of the tool transport system and a pair of opposing fingers of a tool clamp of the tool storage system.
[0006] The hydrostatic tool system may also include a tool storage system. In one preferred embodiment of the invention, the tool storage system is configured as a turret including a plurality of tool assembly receivers. The turret is mounted on a shaft and a plurality of tool assembly receivers are connected to the turret. Each tool assembly receiver is configured to hold and support a tool assembly. The turret may be rotated and indexed to any selected position corresponding to a selected tool assembly. The tool storage system may include hydraulic, pneumatic, electrical or mechanical means to rotate and index the turret, for example a pneumatic rotary actuator. In one preferred embodiment of the invention, the turret is rotated by a rotary actuator, such as a model manufactured by Bimba Manufacturing Company, model No. PTF-196325 rotary actuator 325° with position feedback. Indexing or stopping turret rotation at a selected position is accomplished by a pneumatic stop cylinder such as the model No. M171-DBZ cylinder, 1½″ bore and 1½″ stroke, block mount cylinder, manufactured by the Bimba Manufacturing Company.
[0007] In the alternative, the tool storage system may feature a linear configuration wherein the tool assemblies are arranged side by side in sequence. Similarly, the tool storage system may feature a stacked configuration wherein the tool assemblies are arranged one above another or side by side. For instance, the tool storage system may include stacked rows or stacked turrets as desired.
[0008] In one preferred embodiment of the invention, the tool assembly receivers are configured as tool clamps. Each tool clamp includes a pair of opposing fingers. Each clamp is biased towards a closed position. A tool assembly may be forced against the clamp thereby gaining entry into the tool clamp. The spring bias creates ample compressive holding force to maintain the tool assembly securely in position at the tool storage system. In another preferred embodiment of the invention, the tool assembly receivers are configured as “dummy” spindles. In this embodiment of the invention, a tool assembly may be placed down on the “dummy” spindle with essentially the same motion employed by the tool transport system for placing the tool assembly on the motor driven spindle.
[0009] The hydrostatic tool system according to the present invention may also include a tool transport system. The tool transport system includes, generally, a tool assembly pick and place member for retrieving a tool assembly from the tool storage system and for placing the tool assembly on a motor driven spindle and a tool transport device for transporting the tool assembly between the tool storage system and a motor driven spindle. The tool transport system may also include a system for pressurizing the hydrostatic tool holder. The tool transport system may also include a system for the de-pressurization and extraction of hydraulic fluid from the hydrostatic tool holder.
[0010] In one preferred embodiment of the invention, the tool transport system includes a primary frame mounted to a carriage which may be advanced along an X axis by a horizontal travel actuator between the tool storage system and a motor driven spindle. The horizontal travel actuator may be configured as a rodless cylinder including a piston and a carriage slidable along an outer circumferential surface of a cylinder tube, the piston and the carriage each include magnets, allowing the piston to move the carriage along the cylinder tube by the attraction force between the magnets. A force transmitted to the piston, for instance fluid pressure, causes the piston to travel through the tube and is transmitted to the carriage through magnetic attraction thereby advancing the carriage along the cylinder tube. In one preferred embodiment of the invention, the rodless cylinder is a model TA-MS4D-2½B×2S-OSM, 2½″ bore by 2″ stroke rodless cylinder manufactured by TRD.
[0011] In another embodiment, the tool transport system includes a primary frame mounted to a rotatable carriage, which selectively rotates about a substantially vertical axis by operation of a rotational motion actuator and locates between two or more stations, a first station wherein a tool assembly is retrieved or placed at a tool storage system and a second station wherein the tool assembly is placed on a motor driven spindle. One such rotational motion actuator is manufactured by Bimba Manufacturing Company, model No. Q107221, 150° and 1-{fraction (1/16)}″ bore.
[0012] In one preferred embodiment of the invention, the tool transport system includes a lifting cylinder having a substantially vertical lifting capacity attached to the primary frame. A head frame assembly is attached to the lifting cylinder and is movable with the substantially vertical travel of the lifting cylinder along a Y axis. A clamping arm cylinder is also attached to the head frame assembly. A clamp arm frame is attached to the clamping arm cylinder and is movable with the substantially vertical travel of the clamping arm cylinder along a Y axis. A pair of articulated clamping arms are attached to the clamp arm frame and are actuated by the clamping arm cylinder. In one preferred embodiment of the invention, both the lifting cylinder and the clamping arm cylinder are of the double end type, wherein the piston is held stationary within a frame and the cylinder travels within the frame. In one preferred embodiment of the invention, the lifting cylinder includes a TRD model No. TA-MS4D-3¼B×6S-OSM, 3¼″ bore and 6″ stroke double ended cylinder and the clamping arm cylinder includes a TRD model No. TA-MS4D-2½B×2S-OSM, 2½″ bore and 2″ stroke double ended cylinder. In another preferred embodiment of the invention, the lifting cylinder includes a TRD model No. TA-MS4D-2½B×7S-OSM, 2½″ bore and 7″ stroke double ended cylinder.
[0013] When the lifting cylinder is actuated in an upward direction, the head frame assembly moves vertically upward along the Y axis, and when the lifting cylinder is actuated in a downward direction, the head frame assembly moves vertically downward along the Y axis. When the clamping arm cylinder is actuated in an upward direction, first and second articulated clamping arms move to an open position, and when the clamping arm cylinder is actuated in a downward direction, first and second articulated clamping arms move to a closed or clamping position in gripping articulation.
[0014] In one preferred embodiment of the invention, the tool transport system includes an hydraulic coupler. The hydraulic coupler includes an inlet and an outlet. The hydraulic coupler hydraulically communicates with a pressurized source for an hydraulic fluid. In the preferred embodiment of the invention, the hydraulic coupler is configured to achieve hydraulic energization and de-energization of the hydrostatic tool holder in a substantially leak free manner.
[0015] The hydraulic coupler may be configured as a poppet actuator assembly and includes a poppet actuator inserted within an actuator cap. The poppet actuator is configured as a stem having a longitudinal axis and a central bore. The stem includes a first orifice which extends through the side wall of the stem at or near the first end of the stem and a second orifice which extends through the side wall of the stem at or near the second end of the stem. The stem extends longitudinally through a seal which seats in the actuator cap. The actuator cap includes a central bore including a seat for receiving the seal. The actuator cap attaches to an arm comprising a portion of the head frame assembly and moves vertically upward and downward along the Y axis, with the vertical travel of the lifting cylinder. The poppet actuator assembly also includes an hydraulic test point having a poppet valve. One such test point, the Minicheck® Test Point Coupling, is manufactured by the Schroeder Co. The poppet valve is spring loaded and biased towards a closed position. The hydraulic test point is oriented such that the poppet valve opens against pressure exerted by the poppet actuator stem thus permitting passage of hydraulic fluid past the valve. A more complete description of the operation of the coupler is set forth below in the detailed embodiment section.
[0016] In the preferred embodiment of the invention, a controller device including a control circuit operates and controls the various functions of the hydrostatic tool system. The controller device may be configured as a standalone or a networked personal computing device. The controller operates and controls any or all of the various functions of the hydrostatic tool system including selection of tool, rotation of the turret, travel of the carriage, actuation of the lifting and clamping cylinders, energization and de-energization of the hydraulic coupler and associated source for pressurized hydraulic fluid, operation of the spindle motor and operation of any associated workpiece feed mechanism.
DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIG. 1 is a representative front view of a hydrostatic tool system;
[0018] [0018]FIG. 2 is a representative front view of a tool assembly held by a tool storage system and a tool transport system;
[0019] [0019]FIG. 3 is a representative front view of a tool assembly held by a tool storage system and a tool transport system;
[0020] [0020]FIG. 4 is a representative side view of a tool assembly held by a tool storage system and a tool transport system;
[0021] [0021]FIG. 5 is a representative front view of a tool storage system and a tool assembly held by a tool transport system;
[0022] [0022]FIG. 6 is a representative top view of a tool storage system and a tool assembly held by a tool transport system;
[0023] [0023]FIG. 7 is a representative front view of a tool assembly held by a tool transport system and positioned for placement on a spindle;
[0024] [0024]FIG. 8 is a representative front view of a tool assembly held by a tool transport system being positioned for placement on a spindle;
[0025] [0025]FIG. 9 is a representative side view of a tool assembly held by a tool transport system being positioned for placement on a spindle;
[0026] [0026]FIG. 10 is a representative side view of a tool assembly positioned on a spindle;
[0027] [0027]FIG. 11 is a representative front view of a tool assembly positioned on a spindle and an hydraulic coupler coupled to the hydrostatic tool holder;
[0028] [0028]FIG. 12 is a representative side view of a tool assembly positioned on a spindle and an hydraulic coupler coupled to the hydrostatic tool holder;
[0029] [0029]FIG. 13 is a representative front view of a tool assembly positioned on a spindle and released by the tool transport system;
[0030] [0030]FIG. 14 is a representative front view of a tool assembly positioned on a spindle and released by the tool transport system;
[0031] [0031]FIG. 15 is a representative exploded side cutaway view of a hydrostatic tool holder;
[0032] [0032]FIG. 16 is a representative assembled side cutaway view of a tool assembly including a hydrostatic tool holder;
[0033] [0033]FIG. 17 is a representative exploded side cutaway view of an hydraulic coupler;
[0034] [0034]FIG. 18 is a representative side cutaway view of an hydraulic coupler coupled to the hydraulic fitting of a hydrostatic tool holder;
[0035] [0035]FIG. 19 is a representative side cutaway view of an hydraulic coupler disengaged from the hydraulic fitting of an hydrostatic tool holder;
[0036] [0036]FIG. 20 is a representative schematic of an hydrostatic tool system including a controller according to the present invention;
[0037] [0037]FIG. 21 is a representative front view of a hydrostatic tool system;
[0038] [0038]FIG. 22 is a representative side view of a hydrostatic tool system;
[0039] [0039]FIG. 23 is a representative top view of a hydrostatic tool system; and
[0040] [0040]FIG. 24 is a representative top view of a hydrostatic tool system.
DETAILED DESCRIPTION
[0041] Referring to FIG. 1, hydrostatic tool system 10 is shown including tool assembly 18 , tool storage system 40 , and tool transport system 50 . Hydrostatic tool system 10 also includes drive system 11 including spindle 12 connected to motor 13 by belt 14 . FIGS. 10 - 14 show hydraulic coupler 70 and FIG. 20 shows system controller 100 .
[0042] [0042]FIGS. 2 through 14 depict sequentially the following steps, assemblies and systems: tool assembly 18 A is held in tool storage system 40 for retrieval by tool transport system 50 , (FIGS. 2 through 4); tool assembly 18 A is held by first and second articulated clamping arms 60 A and 60 B for transport to spindle 12 , (FIGS. 5 through 7); and tool assembly 18 A is placed on spindle 12 by tool transport system 50 (FIGS. 8 through 14).
[0043] Referring to FIGS. 4 through 6, tool storage system 40 is shown including turret 41 . Turret 41 is supported by and rotates on turret shaft 42 . As seen in FIG. 6, turret 41 includes a plurality of tool clamps 43 A through 43 D attached to and extending from turret 41 . As seen in FIG. 6, tool storage system 40 is shown supporting tool assemblies 18 B, 18 C and 18 D in tool clamps 43 B, 43 C and 43 D. FIGS. 1, 4 and 5 show rotary actuator 45 connected to turret shaft 42 for advancing turret 41 . FIG. 6 shows turret 41 advancing to a selected orientation to present a selected tool clamp 43 A from which tool assembly 18 A has been removed by tool transport system 50 .
[0044] Referring to FIGS. 2 through 14, tool transport system 50 will be described in further detail. FIGS. 2 through 14 show tool transport system 50 including carriage 51 to which primary frame 55 is attached. Carriage 51 is propelled in either a forward direction F or reverse direction R along an X axis by horizontal travel actuator 52 . As shown, horizontal travel actuator 52 is configured as a rodless cylinder. Carriage 51 travels in response to the travel of a piston of the rodless cylinder and a magnetic attraction between the piston of the rodless cylinder and carriage 51 .
[0045] Tool transport system 50 also includes primary frame 55 connected to carriage 51 . As shown in FIGS. 4 , 9 , 10 and 12 , primary frame 55 supports lifting cylinder 53 . Head frame assembly 56 is attached to lifting cylinder 53 and is movable with the travel of lifting cylinder 53 along a Y axis. Clamping arm cylinder 57 is attached to head frame 61 . Clamping arm cylinder 57 supports clamp arm frame 59 . As seen in FIGS. 5, 7, 8 , 11 , 13 , and 14 , first and second head frame arms 63 A and 63 B are attached to and extend forward from head frame assembly 56 . Second head frame arm 63 B, similar to first head frame arm 63 A, is also shown to advantage in FIGS. 4 and 9.
[0046] Tool transport system 50 also includes first and second articulated clamping arms 60 A and 60 B. As seen in FIGS. 7, 8, 11 , 13 , and 14 , first and second articulated clamping arms 60 A and 60 B include upper sub-arms 66 A and 66 B and lower sub-arms 67 A and 67 B. Upper sub-arms 66 A and 66 B are pivotably connected to lower sub-arms 67 A and 67 B at connector pivot points 58 A and 58 B. Upper ends of first and second articulated clamping arms 60 A and 60 B are pivotably connected to clamp arm frame 59 at clamp arm pivot points 62 A and 62 B. Lower ends of first and second lower sub-arms 67 A and 67 B are pivotably connected to first and second head frame arms 63 A and 63 B at clamp arm pivot points 64 A and 64 B. In the embodiment shown, gripping articulation between the lower ends of lower sub-arms 67 A and 67 B is achieved when clamping arm cylinder 57 travels down as shown in FIG. 11. Release of gripping articulation between the lower ends of lower sub-arms 67 A and 67 B occurs when clamping arm cylinder 57 is actuated for travel in an upward direction as shown in FIG. 13.
[0047] Referring to FIG. 15, hydrostatic tool holder 20 includes inner sleeve 21 nested within outer sleeve 22 . Collar 23 is threadedly engageable with outer sleeve threaded end 68 . Hydraulic fitting 32 is threadedly engageable with outer sleeve bulkhead 96 .
[0048] Referring to FIG. 16, tool assembly 18 A includes hydrostatic tool holder 20 having inner sleeve 21 nested within outer sleeve 22 forming gap 24 . Chamber 69 is defined by gap 24 between outer circumferential surface 26 , shown in FIG. 15, of inner sleeve 21 and inner circumferential surface 25 , shown in FIG. 15, of outer sleeve 22 . Collar 23 includes gripping flange 99 which provides a gripping and lifting member for gripping, lifting, supporting and placing tool assembly 18 A. Hydraulic fitting 32 is threadedly engageable with outer sleeve bulkhead 96 . Chamber 69 is further defined by the nesting and mating configuration of inner sleeve flange 36 and outer sleeve flange 37 , which are sealed against pressure loss by o-ring 39 and are connected by screw 38 , as shown in FIG. 16. Referring to FIGS. 16,18 and 19 , chamber 69 is further defined by the nesting and mating configuration of inner sleeve bulkhead 65 formed at upper end of inner sleeve 21 and outer sleeve bulkhead 96 formed at upper end of outer sleeve 22 . Bleed hole 97 extends through inner sleeve bulkhead 65 and outer sleeve bulkhead 96 . Relief port assembly 98 provides a means for manually releasing hydrostatic pressure from hydrostatic tool holder 20 if required.
[0049] Inner sleeve 21 includes inner bore 27 , as shown in FIG. 15, which is configured to concentrically engage spindle 12 , as shown in FIG. 16. As shown in FIG. 15, outer sleeve 22 includes outer circumferential surface 28 configured to concentrically engage cutting tool 16 , as shown in FIG. 16. Inner sleeve 21 and outer sleeve 22 deflect when hydraulic pressure is exerted within chamber 69 to firmly engage both spindle 12 and cutting tool 16 .
[0050] Hydraulic fluid 35 may be introduced into and pressurized within chamber 69 through hydraulic fitting 32 . In one preferred embodiment of the invention, outer sleeve 22 includes hydraulic fitting 32 which permits introduction, pressurization and extraction of hydraulic fluid 35 into chamber 69 . In the embodiment shown in FIG. 16, hydraulic fitting 32 is configured as hydraulic test point 33 including poppet valve 34 and poppet spring 31 which biases poppet valve 34 towards a closed position. Hydraulic test point 33 is configured to releasably engage and hydraulically communicate with hydraulic coupler 70 , as shown in FIGS. 17 - 19 .
[0051] Referring to FIGS. 16, 18 and 19 , hydrostatic tool holder 20 includes collar 23 including gripping flange 99 which provides a gripping and lifting member for gripping, lifting, supporting and placing tool assembly 18 A. Gripping flange 99 is configured for engagement with first and second articulated clamping arms 60 A and 60 B of tool transport system 50 , as shown in FIG. 5, and first and second opposing fingers 46 A and 46 B of tool clamp 43 A of tool storage system 40 , as shown in FIG. 6.
[0052] As seen in FIGS. 10 through 14, hydrostatic tool system 10 includes hydraulic coupler 70 . As shown in FIG. 17, hydraulic coupler 70 hydraulically communicates with hydraulic pump 73 for hydraulic fluid 35 . Referring to FIGS. 17 through 19, poppet actuator assembly 75 allows transfer of hydraulic fluid 35 from hydraulic pump 73 to and from hydrostatic tool holder 20 .
[0053] Referring to FIGS. 17 through 19, hydraulic coupler 70 includes poppet actuator assembly 75 including poppet actuator 76 inserted within actuator cap 77 . As shown in FIG. 17, poppet actuator 76 is configured having stem 78 having center bore 79 . Stem 78 includes first orifice 80 which extends through a side wall of stem 78 at or near a first end of stem 78 and hydraulically communicating with center bore 79 . Stem 78 also includes second orifice 83 which extends through a side wall of stem 78 at or near a second end of stem 78 and hydraulically communicating with center bore 79 . Stem 78 extends longitudinally through seal 84 which seats in actuator cap 77 . Actuator cap 77 includes actuator cap center bore 87 including actuator cap seat 86 for receiving seal 84 .
[0054] Referring to FIGS. 17 through 19, poppet actuator assembly 75 also includes hydraulic test point 90 including poppet valve 91 slideably disposed within test point housing 93 . Poppet valve 91 includes poppet valve spring 92 which biases poppet valve 91 towards a closed position. Hydraulic test point 90 is oriented such that poppet valve 91 opens against pressure exerted by poppet actuator stem 78 permitting passage of hydraulic fluid 35 past poppet valve 91 . Ninety degree elbow 94 is attached at the end of flexline 95 which attaches to an inlet end of test point housing 93 . Flexline 95 attaches at a second end to hydraulic pump 73 for hydraulic fluid 35 . Test point housing 93 threadedly engages actuator cap 77 and actuator cap 77 threadedly engages actuator cap housing 85 . As shown in FIGS. 10 and 12, actuator cap housing 85 attaches to arm 89 , which in turn is attached to and extends from head frame assembly 56 and moves in substantially vertical upward and downward travel along the Y axis with travel of lifting cylinder 53 . Referring to FIGS. 18 and 19, hydrostatic tool holder 20 is shown positioned on spindle 12 and hydraulic coupler 70 is shown together with the upper coupling portion of tool assembly 18 A, specifically, hydraulic fitting 32 of hydrostatic tool holder 20 .
[0055] In the preferred embodiment of the invention, and referring to FIG. 20, system controller 100 includes processing device 110 and input 102 . Power source 103 provides power as needed to the various systems. System controller 100 operates and controls various functions, devices, assemblies and systems of hydrostatic tool system 10 including compressor 104 . System controller 100 controls selection of cutting tool assembly 18 by actuation of turret drive 45 and rotation of turret 41 . System controller 100 controls horizontal travel by actuation and control of horizontal travel actuator 52 and travel of carriage 51 , actuation and control of lifting cylinder 53 and clamping arm cylinder 57 and thereby the gripping articulation between the lower ends of lower sub-arms 67 A and 67 B when clamping arm cylinder 57 extends or retracts, and the raising and lowering of tool assembly 18 and hydraulic coupler 70 . System controller 100 also controls energization of hydraulic pump 73 , operation of spindle drive motor 13 and operation of any associated workpiece feed mechanism, (not shown). System controller 100 may be configured as a stand alone or a networked personal computing device.
[0056] As previously mentioned, FIGS. 2 through 14 depict a sequence of the following steps involving the referenced assemblies and systems: tool assembly 18 A supported in tool storage system 40 for retrieval by tool transport system 50 , (FIGS. 2 through 4); tool assembly 18 A is held by first and second articulated clamping arms 60 A and 60 B for transport to spindle 12 , (FIGS. 5 through 7); and tool assembly 18 A placed on spindle 12 by tool transport system 50 (FIGS. 8 through 14).
[0057] In operation, a plurality of cutting tool assemblies 18 are stored for selection and use at tool storage system 40 . Tool storage system 40 includes turret 41 mounted on turret shaft 42 . As seen in FIG. 6, turret 41 includes a plurality of tool clamps 43 A through 43 D attached to and extending from turret 41 . Tool storage system 40 is shown supporting tool assemblies 18 A, 18 B and 18 C in tool clamps 43 A, 43 B and 43 C. FIG. 1 shows rotary actuator 45 connected to turret shaft 42 for advancing turret 41 to a selected orientation to present a selected tool assembly 18 for pickup by tool transport system 50 , or a selected tool clamp 43 A through 43 D for placement or storage of tool assembly 18 by tool transport system 50 . Tool selection is made by controller 100 . Turret 41 is rotated by operation of turret drive 45 as required to position a selected cutting tool assembly 18 for picking and transport.
[0058] Referring to FIG. 4, primary frame 55 is propelled along carriage 51 in an X axis towards tool storage system 40 . Referring to FIG. 2, tool transport system 50 has positioned first and second articulated clamping arms 60 A and 60 B directly above collar 23 of the selected cutting tool assembly 18 A.
[0059] Referring to FIGS. 3 and 4, first and second articulated clamping arms 60 A and 60 B have achieved gripping articulation about collar 23 of the selected cutting tool assembly 18 A. Gripping articulation is achieved by first and second articulated clamping arms 60 A and 60 B by movement of clamping arm cylinder 57 in a downward direction. Clamp arm frame 59 , which is attached to clamping arm cylinder 57 , also moves in a downward direction relative to first and second head frame arms 63 A and 63 B applying a downward force to upper sub-arms 66 A and 66 B which are pivotably connected to lower sub-arms 67 A and 67 B at connector pivot points 58 A and 58 B (as shown in FIG. 6).
[0060] Referring to FIGS. 5 through 7, once selected cutting tool assembly 18 A is grasped by first and second articulated clamping arms 60 A and 60 B, carriage 51 initiates movement away from turret 41 . Carriage 51 continues travel until cutting tool assembly 18 A is positioned over spindle 12 as shown in FIG. 7.
[0061] Referring to FIGS. 8 and 9, cutting tool assembly 18 A is lowered along the Y axis and placed on spindle 12 by actuation of lifting cylinder 53 . As seen in FIG. 9, lifting cylinder 53 lowers and the connected head frame assembly 56 lowers as well, setting tool assembly 18 A on spindle 12 .
[0062] Referring to FIGS. 10 through 12, head frame assembly 56 continues downward travel by operation of lifting cylinder 53 and hydraulic coupler 70 is moved into coupling engagement with hydraulic fitting 32 of cutting tool assembly 18 A.
[0063] Referring to FIG. 18, hydraulic coupler 70 is shown engaging hydraulic fitting 32 of hydrostatic tool holder 20 . FIG. 18 is typical of coupling engagement for the purpose of either energizing or de-energizing hydrostatic tool holder 20 . Opposing ends of poppet actuator stem 78 act against hydraulic test point 33 and poppet valve 34 of hydrostatic tool holder 20 and poppet valve 91 of poppet actuator assembly 75 opening poppet valves 34 and 91 to permit flow of hydraulic fluid 35 from hydraulic pump 73 through hydraulic coupler 70 to hydrostatic tool holder 20 . As shown in FIG. 18, when hydraulic coupler 70 is engaged to hydraulic fitting 32 as shown, hydraulic communication is permitted between hydraulic pump 73 for hydraulic fluid 35 , shown in FIG. 17, and chamber 69 of hydrostatic coupler 20 , shown in FIG. 18, through first orifice 80 , second orifice 83 and center bore 79 of stem 78 .
[0064] Following hydrostatic energization of hydrostatic tool holder 20 , hydraulic coupler 70 is lifted away from hydraulic fitting 32 of tool holder 20 , as shown in FIG. 19, by vertical up movement of lifting cylinder 53 , as shown in FIGS. 13 and 14. Gripping articulation between the lower ends of lower sub-arms 67 A and 67 B is released as clamping arm cylinder 57 moves vertically up, as shown in FIG. 13, releasing collar 23 of cutting tool assembly 18 A. First and second articulated clamping arms 60 A and 60 B lift away from collar 23 of cutting tool assembly 18 A as lifting cylinder 53 continues upward travel, as shown in FIGS. 13 and 14.
[0065] Cutting tool assembly 18 is now ready for operation. A substantially reverse order operation is followed to remove, transport and store cutting tool assembly 18 . To de-energize hydrostatic tool holder 20 , hydraulic coupler 70 is moved into coupling engagement with hydraulic fitting 32 of hydrostatic tool holder 20 . As this occurs, the opposing ends of poppet actuator stem 78 act against poppet valve 34 of hydrostatic tool holder 20 and poppet valve 91 of poppet actuator assembly 75 opening valves 34 and 91 , permitting flow of hydraulic fluid 35 from the hydrostatic tool holder 20 through hydraulic coupler 70 .
[0066] Referring to FIGS. 21 through 24, another preferred embodiment of hydrostatic tool system 210 is shown to advantage. Hydrostatic tool system 210 is nearly identical to hydrostatic tool system 10 as shown in FIG. 1, with the exception that motion of tool transport system 250 is rotational as opposed to linear. Referring to FIG. 21, it will be seen that hydrostatic tool system 210 includes tool assembly 218 , tool storage system 240 , tool transport system 250 , hydraulic coupler 270 , and system controller 206 . Hydrostatic tool system 210 also includes drive system 211 including spindle 212 connected to motor 213 by drive belt 214 . Drive system 211 may also include tensioner 215 for tensioning drive belt 214 .
[0067] Tool storage system 240 is shown including turret 241 . As seen in FIG. 21, turret 241 is supported by and rotates on turret shaft 242 . Turret shaft 242 is supported by thrust bearings 246 and 247 . As seen in FIGS. 23 and 24, turret 241 includes a plurality of “dummy” spindles 243 A through 243 D attached to and extending from turret 241 . Preferably, dummy spindles 243 A through 243 D are undersized in circumference compared to spindle 212 , to permit ease of placement of a tool assembly on the dummy spindle. Rotary actuator 245 is connected to turret shaft 242 for advancing turret 241 to a selected orientation to present a selected tool assembly 218 A for removal from tool storage system 240 by tool transport system 250 . Referring to FIG. 23, tool assembly 218 A is shown supported on turret 241 located in position on “dummy” spindle 243 A. Pneumatic stop cylinder 248 provides a means for stopping rotation of turret 241 at the selected location.
[0068] Referring to FIGS. 21 and 22, another preferred embodiment of tool transport system 250 is shown including carriage 251 to which primary frame 255 is attached. Carriage 251 is rotatable about a substantially vertical axis L, on shaft assembly 265 , by transport system rotary actuator 252 . Shaft assembly 265 is supported by thrust bearings 262 and 264 . Carriage 251 is rotatable from a first position wherein clamping arms 260 A and 260 B are positioned over tool storage system 240 , as seen in FIG. 23, and a second position wherein first and second articulated clamping arms 260 A and 260 B are positioned over spindle 212 , as seen in FIG. 24.
[0069] In the embodiment shown, rotary actuator 245 for tool storage system 240 and transport system rotary actuator 252 are configured as a pneumatic rotary actuator of the double rack and pinion gear type.
[0070] As shown in FIG. 22, tool transport system 250 also includes primary frame 255 connected to carriage 251 . Primary frame 255 supports lifting cylinder 253 . Head frame assembly 256 is attached to lifting cylinder 253 and is movable with the travel of lifting cylinder 253 along a Y axis. Clamping arm cylinder 257 is attached to head frame 261 . Clamping arm cylinder 257 supports clamp arm frame 259 . As seen in FIG. 21, tool transport system 250 also includes first and second articulated clamping arms 260 A and 260 B. In the embodiment shown, as with the previously described tool transport system 50 , FIGS. 1 through 14, gripping articulation between clamping arms 260 A and 260 B is achieved when clamping arm cylinder 257 travels down. Release of gripping articulation occurs when clamping arm cylinder 257 is actuated for travel in an upward direction.
[0071] While this invention has been described with reference to the detailed embodiments, this is not meant to be construed in a limiting sense. Various modifications to the described embodiments as well as the inclusion or exclusion of additional embodiments will be apparent to persons skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention. | An hydrostatic tool system including a tool assembly having a hydrostatic tool holder for holding a rotating tool, for example a machine or cutting tool. The hydrostatic tool system may also include a tool storage system, a tool transport system and a tool drive system. The hydrostatic tool system may also include an hydraulic coupler for hydraulically connecting the hydrostatic tool holder to a pressurizing or depressurizing source. The hydrostatic tool system may also include a system controller. | 8 |
BACKGROUND OF THE INVENTION
1. Technical Field
This invention generally relates to mechanisms for supporting vehicle tailgates. More particularly, the invention relates to an insert and cable assembly for supporting a tailgate when in a substantially horizontal open position. Specifically, the invention relates to an insert that interlocks with an eyelet disposed at one end of a cable, the insert being selectively rotatable within the eyelet to secure the eyelet to a fastener extending from the vehicle sidewall or tailgate.
2. Background Information
Many vehicles, such as pickup trucks, are provided with tailgates that may be swung between open and closed positions. When the tailgate is in the closed position, it is substantially vertically oriented with respect to the vehicle bed floor and a load held on the bed is prevented from sliding off the vehicle and into the road. When the user wishes to unload goods carried on the vehicle, the tailgate is lowered into a substantially horizontal open position, thereby providing easier access to the load.
Tailgates are typically supported in the open position by a pair of coated, flexible steel cables that are each connected at a first end to the vehicle sidewall and at a second end to one side of the tailgate. The cables are connected to the sidewall and tailgate by way of fasteners which are inserted through eyelets extending outwardly from the first and second ends of the cable. It is common for the two eyelet connectors to be dissimilar in shape. The tailgate eyelet connector typically is generally “O”-shaped with a centrally located circular hole formed therein. The sidewall eyelet connector may be generally elliptical in shape with a keyhole-shaped aperture formed therein. A spring-biased, substantially rectangular plate is clamped around the base of the sidewall eyelet and extends partially into the aperture. The fasteners for securing the eyelets to the vehicle may be bolts, rivets, pins and screws or any other suitable connector device. The shaft of the fastener received through the tailgate eyelet connector is of substantially the same size as the centrally-located hole. Consequently, very little rattling noise is produced by that connection when the vehicle is moving. A rattle is, however, frequently generated at the connection between the sidewall and the sidewall eyelet connector. The fastener used for this connection has a head portion with a diameter that is smaller than the wider portion of the keyhole-shaped aperture but is larger than the narrower portion of the aperture. The spring-biased plate extends into the wider portion of the aperture and toward the narrower portion of the aperture. The fastener is inserted into the wider portion of the aperture by pushing the plate out of the way either with the head of the fastener or with a screwdriver or similar device. The eyelet is then moved relative to the fastener so that the shaft of the fastener slides into the narrower portion of the aperture. The plate springs back into its initial position, thereby clamping the fastener and eyelet together. The diameter of the shaft of the fastener is typically less than the diameter of the narrower portion of the aperture. Consequently, when the vehicle is moving, there is movement between the eyelet and the fastener shaft and a rattling noise is generated. In addition to this problem, the plate tends to contribute to the corrosion of the eyelets because it is usually made from a dissimilar metal and tends to set up a galvanic corrosion cell. Additionally, it is common for users to remove the tailgate altogether so that they can either load or unload a particularly heavy item from the vehicle bed or carry a heavy item on the bed floor. The above-described sidewall eyelet connector is not particularly easy to release and frequently requires that a screwdriver or similar tool be used to force the plate out of engagement with the fastener. This can make the removal of the tailgate more difficult.
There is therefore a need in the art for a cable assembly that may be connected to both the sidewall and tailgate quickly and easily. There is furthermore a need for a cable assembly that does not rattle when the vehicle is moving and has a decreased tendency to rust.
SUMMARY OF THE INVENTION
The present invention is directed to an insert that may be used in tailgate cable assemblies and to a tailgate cable assembly incorporating the same. The tailgate cable assembly is an elongated, flexible cable that has eyelet connectors at each end and which is used to secure a rotatable tailgate to the sidewall of a vehicle. Fasteners extending from the sidewall and tailgate are received through apertures in the eyelets. At least one of the eyelets incorporates a removable insert that is rotatable between a first position, where the fastener may be either inserted or withdrawn from the eyelet, and a second position where the insert locks the fastener within the aperture in the eyelet. The insert is a “C”-shaped member that has a channel formed in a flange extending from its rear wall and a portion of the eyelet's interior peripheral surface surrounding the aperture is received within the channel and locks the C-shaped member and eyelet together.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred embodiment of the invention, illustrative of the best mode in which applicant has contemplated 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 view of a vehicle with the tailgate in an open position showing the tailgate being supported by the cable assembly in accordance with the present invention;
FIG. 2 is an exploded perspective view of the sidewall eyelet connector end of the tailgate cable assembly;
FIG. 2A is a rear elevational view of the sidewall connector with an insert received within a wider portion of the aperture;
FIG. 2B is a rear elevational view of the sidewall connector with the insert being moved into the narrower portion of the aperture;
FIG. 2C is a rear elevational view of the sidewall connector with the insert engaged with the base;
FIG. 3 is a perspective view of the sidewall connector in an open position;
FIG. 4 is a perspective view of the sidewall connector with the wider portion of the hole positioned over a fastener extending from the vehicle sidewall;
FIG. 5 is a front elevational view of the sidewall connector of FIG. 4 ;
FIG. 6 is a cross-sectional side view of the sidewall connector through line 6 — 6 —of FIG. 5 ;
FIG. 7 is a front elevational view of the sidewall connector with the fastener engaged in the narrower portion of the hole;
FIG. 8 is a cross-sectional side view of the sidewall connector through line 8 — 8 —of FIG. 7 ;
FIG. 9 is a partial cross-sectional rear view of the sidewall connector through line 9 — 9 of FIG. 8 ;
FIG. 10 is a front elevational view of the sidewall connector with the insert rotated into the locked position around the fastener;
FIG. 11 is a cross-sectional side view of the sidewall connector through line 11 — 11 of FIG. 10 ;
FIG. 12 is a rear elevational view of the sidewall connector through line 12 — 12 of FIG. 11 ; and
FIG. 13 is a cross-sectional left side view of the sidewall connector through line 13 — 13 of FIG. 10 .
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1–3 , there is shown a vehicle 10 of the type having a bed with a floor 12 , sidewalls 14 , 16 and a tailgate 18 . Tailgate 18 is mounted to vehicle 10 by way of rod ends 20 and is rotatable about rod ends 20 between a vertical position (not shown) and a horizontal position ( FIG. 1 ). Tailgate 20 and supports 22 on sidewalls 14 , 16 are connected together by a pair of cable assemblies 24 that assist in supporting tailgate 20 when it is in the horizontal, open position. Only one of the cable assemblies 24 is illustrated in FIG. 1 and described below for the sake of clarity. It will be understood, however, that the two cable assemblies are substantially identical.
Cable assembly 24 comprises an elongated, flexible steel cable 26 having a tailgate connector 28 secured to a first end thereof and a sidewall connector 30 secured to a second end thereof. Tailgate connector 28 is of the type commonly used in the industry, being a substantially circular eyelet with a central hole therein and is secured to the tailgate by a suitable fastener inserted through the central hole. Sidewall connector 30 ( FIGS. 2&3 ) comprises a base 32 having a shaft 34 extending outwardly therefrom. Shaft 34 includes a pair of flanges 36 that are crimped around cable 26 to secure connector 30 thereto. Base 32 has a substantially keyhole-shaped aperture 38 formed therein and aperture 38 has a wider portion 38 a and a narrower portion 38 b . The maximum width “R” of portion 38 a is greater than the maximum width “S” of portion 38 b . A lip portion 40 separates wider portion 38 a from narrower portion 38 b . Base 32 has a thickness “T”. When viewed from the front, narrower portion 38 b of base 32 is substantially C-shaped and has an arcuate interior peripheral surface 42 .
Referring to FIGS. 2–6 , an insert 44 , in accordance with the present invention, is provided for engagement with base 32 . Insert 44 is manufactured from a rigid material preferably plastics such as acetal, polyester, nylon and filled nylon materials or metals compatible with those from which base 32 is manufactured. Insert 44 comprises a substantially C-shaped member with a front wall 46 , a rear wall 48 , an outer peripheral wall 50 and an interior opening 57 . Outer peripheral wall 50 of insert 44 preferably is ridged so as to provide a gripping surface for the fingers of a user. Front wall 46 of insert 44 includes a C-shaped groove 52 and a recessed fastener-engaging surface 54 . As may be seen from FIGS. 2&3 , both narrower portion 38 b of aperture 38 and insert 44 are substantially C-shaped and have a substantially identical radius of curvature. A flange 56 extends outwardly from and normal to rear wall 48 . Flange 56 is generally C-shaped when viewed from the rear, has an interior surface 58 , an exterior surface 60 and a chamfered lip 62 . Interior surface 58 of flange 56 defines an interior opening 57 within insert 44 . An U-shaped channel 64 ( FIG. 6 ) is formed between lip 62 and rear wall 48 of insert 44 . The width of channel 64 is substantially equal to the width “T” of base 32 . As may be most easily seen in FIG. 5 , the leading edges 66 of groove 52 and surface 54 are angled to guide a fastener 68 toward the interior surface 58 of flange 56 .
Referring to FIGS. 2 through 2C , insert 44 is engaged with sidewall connector 30 in the following manner. Flange 56 of insert 44 is inserted into the wider portion 38 a of aperture 38 in base 32 and is moved in the direction of arrow “A” ( FIG. 2 ) until the rear wall 48 of insert 44 rests on the front surface 32 a of base 32 . The initial orientation of insert 44 relative to base 32 is not critical because the component is twisted slightly as it is slid along base 32 and into narrower portion 38 b of aperture 38 . So, for example, insert 44 may be oriented as shown in FIG. 2 or as it is shown in FIG. 2A or in any other orientation that will bring rear surface 48 into contact with front surface 32 a of base 32 . Insert 44 is then moved in the direction of arrow “B” ( FIG. 2B ) until flange 56 is received in narrower portion 38 b of aperture 38 . Insert 44 is twisted to cause chamfered lip 62 on flange 56 to ride over rear surface 32 b of base 32 . Insert 44 is simultaneously twisted and moved in the direction of arrow “B” until the interior surface 42 of base 32 is received within the channel 64 of insert 44 and abuts exterior surface 60 of flange 56 ( FIGS. 2& 6 ). Flange 56 frictionally engages base 32 to retain insert 44 on base 32 . Once insert 44 is retained on base 32 , cable assembly 24 is ready to be connected to support 22 and insert 44 is in a first position where it is able to receive a fastener 68 therein. The portion of base 32 that surrounds narrower portion 38 a of aperture 38 and onto which insert 44 is engaged, is substantially flat (see FIG. 6 ) and insert 44 is rotatable on this substantially flat portion of base 32 as will be hereinafter described.
Fastener 68 comprises a head 68 a , a body 68 b and a shaft 68 c . Fastener 68 is mounted to support 22 via washers 70 , 71 and nut 72 to support 22 . Body 68 b of fastener 68 has a height “V” which is substantially the same as the width “W” of flange 56 of insert 44 ( FIG. 6 ). The diameter “X” of body 68 b of fastener 68 ( FIG. 5 ) is substantially the same as the width “Y” of opening 57 formed by interior surface 58 of flange 56 . Head 68 a of fastener 68 has a diameter “X” that is greater than the diameter “Y” of interior surface 58 of insert 44 , but is less than the diameter “Z” of groove 52 of insert 44 . The height “J” of head 68 a of fastener 68 may be less than, equal to or greater than the depth “K” of groove 52 . When fastener 68 is mounted to support 22 , it extends outwardly from a front surface 22 a of support and is disposed substantially at right angles thereto.
Referring to FIGS. 4–13 , cable assembly 24 may be secured to fastener 68 in the following manner. Sidewall connector 30 of cable assembly 24 is brought into the proximity of fastener 68 and is moved in the direction of arrow “C” ( FIG. 4 ) so that fastener 68 enters wider portion 38 a of aperture 38 . The user grasps cable 26 and pulls the same in the direction of arrow “D” ( FIG. 5 ) so that base 32 slides laterally with respect to washer 70 . This lateral movement causes base 32 to slide past fastener 68 so that body 68 b of fastener 68 enters narrower portion 32 b of base 32 . Continued movement of cable 26 in the direction of arrow “D” causes body 68 b to slide between leading edges 66 of insert 44 and toward interior surface 58 of flange 56 . The lateral movement causes the lower surface 74 of head 68 a to ride over fastener engaging surface 54 of insert 44 . Ultimately, the outer surface 76 of body 68 b abuts the interior surface 58 of flange 56 ( FIGS. 7&8 ). The relative sizes of the body 68 b and insert 44 causes the sidewall connector 30 to be wedged between lower surface 74 of head and washer 70 . However, fastener 68 is not locked within sidewall connector 30 and the two components may be disengaged from each other by pushing cable 26 in the opposite direction to arrow “D”. In order to lock fastener 68 and sidewall connector 30 together, insert 44 must be rotated in the direction of either arrow “E” or arrow “F” ( FIG. 7 ) until insert 44 is disposed in the position indicated in FIGS. 10–13 . Insert 44 rotates about an axis Q–Q′ ( FIG. 8 ) that lies substantially at ninety degrees to the flat portion of base 32 surrounding narrower portion 38 b of aperture 38 . In this position, insert 44 prevents fastener 68 from being removed from aperture 38 . Furthermore sidewall connector 30 is prevented from moving laterally in the direction of arrow “D” or in the opposite direction thereto, but is free to rotate around fastener 68 as is indicated by the arrow in FIG. 10 .
Insert 44 may be provided as a retrofit component for cable assemblies known in the prior art that are presently manufactured with a spring-biased plate (not shown) extending into the wider portion the aperture in the base. In order to retrofit such known cable assemblies with insert 44 , the spring-biased plate would be removed from the base and the insert 44 could then be connected into the base 32 in the manner described above with respect to the cable assembly in accordance with the present invention. Alternatively, a cable assembly in accordance with the present invention may be manufactured and then sold with the insert 44 engaged with the base 32 .
The tailgate connector 28 of the cable assembly 24 may be substantially identical to the tailgate connector of cable assemblies known in the prior art and may furthermore be connected to the tailgate of a vehicle in the same manner as previously known tailgate connectors. However, it will be understood that the tailgate connector 28 of the present invention may be of substantially identical structure and function as the sidewall connector 30 as herein disclosed.
When cable assembly 24 is connected between tailgate 18 and support 22 and tailgate 18 is in the open position, cable 26 is in tension and interior peripheral surface 42 of base 32 lies in direction contact with fastener 68 . Insert 44 does not bear any significant load when cable 26 is in tension. The only load borne by insert 44 is equal to the column strength of cable 26 itself. When tailgate 18 is in a closed position, cable 26 is no longer under tension and insert 44 again does not bear any significant load.
It will further be understood that while fastener engaging surface 54 is disposed a distance inwardly of front wall 46 of insert 44 , surface 54 and front wall 46 may be coplanar with each other. Front wall 46 is provided a distance outwardly from surface 54 so that outer peripheral wall 50 of insert 44 has some depth for easy of rotating insert 44 between its open and closed positions. Insert 44 is designed to be eccentric to the centerline of fastener 68 . This provides minimal clearance between fastener 68 and the rotated insert 44 to substantially prevent movement and subsequent rattle of the installed assembly.
Furthermore, while insert 44 is shown in use on a sidewall connector 30 having a keyhole-shaped aperture 38 therein, it will be understood that insert 44 may be used on a sidewall connector having a differently shaped aperture therein. Insert 44 would be engaged with the base of the sidewall connector in the manner as described above and would then be utilized to define a region within that differently shaped aperture that would be substantially the same diameter as the fastener body to which the sidewall connector is to be secured.
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. | An insert and a tailgate cable assembly incorporating the same. The tailgate cable assembly is a cable having eyelet connectors at each end and which is used to secure the sidewall of a vehicle to a rotatable tailgate. Fasteners extending from the sidewall and tailgate are received through apertures in the eyelets. At least one of the eyelets incorporates a removable insert that is rotatable between a first position, where the fastener may be either inserted or withdrawn from the eyelet, and a second position where the insert locks the fastener within the aperture in the eyelet. The insert is a “C”-shaped member that interlocks with the eyelet's interior peripheral surface surrounding a portion of the aperture. | 8 |
BACKGROUND OF THE INVENTION
The field of the present invention is the production of expandable thermoplastic resin particles which can be expanded under low temperature conditions to form fine cell structure foams of density lower than 2.0 pcf.
Polypropyl particles tend to lose blowing agent rapidly after impregnation. U.S. Pat. No. 4,303,756 describes a process for producing polypropylene-polyvinyl aromatic monomer interpolymers which can be impregnated and retain the blowing agent for sufficient time to allow expansion. However, these interpolymers cannot be foamed at temperature of 100° C. normally used to foam thermoplastic resins. U.S. Pat. No. 3,144,436 teaches to viscbreak polypropylene polymers to lower molecular weight polymers by extruding the polymers with a peroxide in the absence of oxygen.
SUMMARY OF THE INVENTION
I have now found that certain interpolymers of polypropylene and polyvinyl aromatic monomers, when viscbroken to alter the rheological properties during the preparation of the interpolymer in the presence of a lubricant and cell control additive, can be impregnated with a blowing agent to give a product which can be expanded under lower temperature (100° C.) conditions to give low density, fine cell structure foam particles.
DETAILED DESCRIPTION OF THE INVENTION
The process of this invention comprises
(a) forming an intimate mixture of (1) a copolymer of propylene and sufficient olefin comonomers to give said copolymer a melting peak of less than 140° C. with (2) a lubricant and cell control agent;
(b) suspending, in an aqueous medium containing 0.01 to 5 percent by weight base on the amount of water of a suitable suspending agent, the intimate mixture from (a) and 0.05 to 2.0 percent by weight based on vinyl aromatic monomer of a catalyst mixture comprising at least one catalyst having a 10-hour 1/2-life temperature of between about 40° and about 110° C., and a high temperature viscbreaking catalyst having a 10-hour 1/2-life temperature of between about 115° and about 140° C. in a ratio of between about 1:1 and 1:2; said catalyst mixture being dissolved in vinyl aromatic monomer;
(c) adding to said suspension vinyl aromatic monomer such that the amount of monomer is 35 to 80 percent by weight based on copolymer plus monomer;
(d) heating said suspension to a temperature of about 70° to about 95° C. and maintaining at that temperature to polymerize said monomer in or on said copolymer to form a polypropylene-polyvinyl aromatic monomer interpolymer;
(e) raising the temperature of the suspension to about 130° to about 150° C. and maintaining at that temperature for times sufficient to substantially viscbreak the interpolymer;
(f) cooling said suspension to room temperature, separating the interpolymer, washing with water and drying in air;
(g) impregnating said interpolymer with a blowing agent to give expandable polypropylene-polyvinyl aromatic monomer interpolymer which can be expanded at 100° C. or less to fine cell structure foams of density less than 2.0 pounds per cubic foot.
Prior to the impregnation step (g), the product from step (f) may be reintroduced into the reactor and steps (b) through (f) may be repeated. This is especially desirable to obtain the higher percentages of vinyl aromatic monomer, rather than attempting to put all the monomer into the polypropylene copolymer in a single polymerization.
Particles is used herein to designate beads, pellets, or cominuted pieces.
The propylene copolymer used as base for the interpolymer must contain sufficient olefin comonomers to give said copolymer a melting peak of less than 140° C., preferably less than 130° C.
The olefin comonomers in the propylene copolymer may be ethylene, 1-butene or mixtures thereof. The melting peak is measured by Differential Scanning Calorimeter (DSC) by ASTM method D3418-82 at a heating rate of 20° C./min.
The intimate mixture of polypropylene copolymer and a lubricant and cell control agent is formed by extrusion of a blend of the components. The lubricants may be various polymer additives, waxes, organic halogen flame retardant compounds, amides, amines and esters. Especially useful was ethylene bis-steramide, alone or in conjunction with zinc stearate. The ethylene bis-stearamide (Acrawax-C, sold by Glyco Inc.) is preferably used in amount of from about 2% to about 4% by weight based on interpolymer. Zinc stearate is used in amounts of 0.2-0.4% by weight, if used at all.
The suspending agent system is selected from water soluble high molecular weight materials, e.g., polyvinyl alcohol or methyl cellulose and slightly water soluble inorganic materials, e.g., calcium phosphate or magnesium pyrophosphate. In addition to the slightly water soluble suspending agents, there may be added a modifier such as sodium dodecylbenzene sulfonate. The amount of suspending agent added is 0.01 to 5% by weight based on the amount of water.
The vinyl aromatic monomer used may be styrene, alpha-methylstyrene, nuclear-methylstyrene, p-tert-butylstyrene, chlorostyrene, bromostyrene, and mixtures thereof.
The catalyst mixture comprises free radical catalysts. At least one catalyst having a 10-hour 1/2-life temperature of between about 40° and about 110° C. is used to polymerize the vinyl aromatic monomer within the polypropylene copolymers. Suitable examples of polymerization catalysts are benzoyl peroxide, lauroyl peroxide, tert-butyl perbenzoate and tert-butyl peracetate. Also used in a high temperature catalyst having a 10-hour 1/2-life temperature of between about 115° and about 140° C. which is used to viscbreak the polypropylene-polyvinyl aromatic monomer interpolymer. Particularly suitable for this use is dicumyl peroxide. The catalysts are normally used in amounts of 0.05 to 2.0% by weight based on vinyl aromatic monomer in a ratio of polymerization catalysts: viscbreaking catalyst of between about 1:1 to 1:2. The catalysts are dissolved in sufficient vinyl aromatic monomer to give a solution prior to addition to the suspended polypropylene particle.
The vinyl aromatic monomer added to the suspension is absorbed by the copolymer and penetrates into the inside portion of the propylene-ethylene copolymer and is there polymerized in or on the copolymer. The resultant product is referred to herein as an "interpolymer". In this reaction, 20 to 60% by weight of the copolymer and 40 to 80% by weight of the vinyl aromatic monomer are used. When the amount of the vinyl aromatic monomer is less than 40% by weight, the expansion ratio of a resulting foamed structure decreases, and a foamed structure of low density cannot be obtained. Amounts of vinyl aromatic monomer greater than 80%, cause elasticity, thermal stability and oil resistance of the resulting foamed product to deteriorate.
The vinyl aromatic monomer and the polymerization catalysts may be added separately or as a solution of catalyst in the monomer. The two can be added all at once or, preferably in incremental portions to prevent suspension instability. The monomer and catalyst can also be emulsified with suitable emulsifying agent and added to the suspension of copolymer resin as an emulsion.
The polymerization cycle consists of heating the suspension of copolymer, monomer and catalysts to a temperature of about 70°-90° C., holding at this temperature for at least 1 hour, preferably from 1 to 3 hours, to polymerize the bulk of the monomers in the polypropylene copolymer, and then raising the temperature to about 130°-150° C. and holding at this temperature for at least 1 hour, preferably 1-4 hours, to substantially viscbreak the interpolymer to a melt flow (condition L) of at least 10 and polymerize any residual vinyl aromatic monomer in the mixture.
Viscbreaking is the intentional chain scission of polypropylene to produce lower molecular weight, a more narrow molecular weight distribution, a slow crystallization rate and faster molecular relaxation time in the molten state.
Impregnation of the viscbroken interpolymer is accomplished by mixing the interpolymer in water with the blowing agent and a surfactant, such as polyvinyl alcohol, methocel or sodium dodecylbenzene sulfonate. Because the polypropylenes do not retain blowing agents well, the presence of polyvinyl aromatic monomer helps to retain the blowing agents. To ensure the retention of the blowing agents after impregnation, the polymer must be cooled. The materials are normally stored at lower temperatures to prevent loss of blowing agent.
The blowing agents suitable in the impregnation include aliphatic hydrocarbons such as butane, n-pentane, isopentane, n-hexane, and neopentane, cycloaliphatic hydrocarbons such as cyclopentane and halogenated hydrocarbons such as methyl chloride, ethyl chloride, methylene chloride, trichlorofluoromethane, dichlorodifluoromethane, etc. These blowing agents can be used alone or as mixtures of two or more thereof. The preferred amount of the blowing agent is in the range of 5 to 20% by weight based on the weight of the polypropylene-polyvinyl aromatic monomer interpolymer. If desired, a solvent may be used, such as toluene or benzene. The solvent may be used in amounts of 2-6% by weight based on interpolymer.
The present invention is further illustrated in the following Examples in which all parts and percentages are by weight.
EXAMPLE I
(a) Addition of lubricant and cell control agent to polypropylene
Polyproplene copolymer particles, containing 4.4% by weight (as reported by manufacturer) of ethylene copolymerized therein, having a M.F. value of 3.80 and a melt peak of 128° C., were blended with 3% by weight of ethylene bis-stearamide as lubricant and cell control agent. The mixture was extruded in a MPM 11/2" extruder at about 148° C. through 0.125" die holes into cold water and the strands cut into pellets of M.F. 5.35.
(b) Preparation of Polypropylene-polystyrene Interpolymer
To a 25 gallon reactor was added 200 parts of water, 100 parts of the polypropylene pellets from (a) above, 0.9 part of tricalcium phosphate, 0.04 part of sodium dodecylbenzene sulfonate to form a suspension. The reactor was heated to 91° C. A premix of 0.36 part of benzoyl peroxide as primary catalyst, 0.36 part of tert-butyl perbenzoate as secondary catalysts, and 0.77 part of dicumyl peroxide as viscbreaking catalyst in sufficient stryene to dissolve the catalysts was added to the reactor along with the remainder of 113 parts of styrene. The reactor was maintained at 91° C. for 1.5 hours and then the temperature was raised to 140° C. over 2 hours and maintained at 140° C. for 3 hours. After cooling, the reaction mixture was removed from the reactor, acidified to remove suspending agents, and the particles separated from the aqueous medium, washed with water and air dried. The polypropylene-polystyrene interpolymer thus recovered had a melt flow (condition L) of 22.0 and a polystyrene content of 53% by weight.
(c) Impregnation of Polypropylene-polystryene Interpolymer
The interpolymer pellets from (b) above were impregnated with isopentane by charging to a 25 gallon reactor, 100 parts of interpolymer from (b), 100 parts of water, 0.031 parts of sodium dodecylbenzene sulfonate, 2.5 parts of toluene, and 0.031 part of ethylene bis-stearamide. Over 45 minutes, 15.0 part of isopentane was charged into the suspension of interpolymer. The suspension was then heated to 60° C. over 45 minutes and held at 60° C. for 7 hours. The reactor was cooled and the polymer particles separted from the suspension medium. The final expandable particles were expanded in a 55 gal (Rodman-type) expander at 100° C. In continuous expansion a density of 2.2 pcf was obtained; and in a batch expansion a density of 1.6 pcf was obtained. The foamed particles had very fine cell structure, and were very heat resistant during molding.
EXAMPLE II
The method of Example I was repeated on 4 different base polypropylenes with the changes given below. Sample A was an exact duplicate of the Example I run. Sample B used as base material a copolymer previously viscbroken from a M.F. (condition L) of 6.0 to a M.F. of 17.9. Samples C and D were identically commercially available polypropylene copolymers of M.F. of 4.44 and a melt peak of 129° C. Sample D was extruded with 3% ethylene bis-stearamide; (Acrawax-C) in an NRM 21/2" Extruder at about 160° C. through 40 mil die holes to produce small pellets (98% through 12 and on 18 mesh, U.S. Standard Sieve). The results are shown in Table I. All Samples had 53% polystyrene in the final interpolymer.
TABLE I______________________________________Sample No. A B C D______________________________________Starting M.F. 3.8 17.9 4.44 4.44Extrusion with 5.42 22.16 6.10 6.28Acrawax, M.F.Interpolymer, M.F 27.0 22.22 35.96 26.46Batch Pre-expansion, 1.38 1.44 1.29 1.47density, p.c.f.______________________________________
All samples, except number C, molded well. Sample C expanded readily but did not fuse well. The smaller particle D sample fused well. If is apparent from Sample B that if pre-viscbroken polypropylene is available it works well, but there is no advantage over viscbreaking during the interpolymer formation.
EXAMPLE III
A series of runs was made starting with commerically available polypropylene copolymers of M.F. (condition L) 4.44 and a melt peak of 129° C. As a first processing step, all samples were extruded with 3% Acrawax-C in an NRM Lab 21/2" extruder at about 160° C. through 40 mil die holes to produce small pellets (98% through 12 and on 18 mesh, U.S. Standard Sieve) having M.F. of 6.28. In the second processing step (corresponding to Example I (b)) the level of styrene in the feed was adjusted to produce the desired polystryene level in the interpolymers as shown in Table II. Sample E illustrates the use of double interpolymerization to obtain higher percents of polystyrene; in this case 69%. In the double interpolymerization, a first polymerization with about 50% styrene was run, and then a second polymerization was run by reintroducing the interpolymer from the first polymerization with sufficient styrene and peroxides to make up the desired total polystyrene content and again run through the temperature cycle. Sample A was run exactly as in Example I, but densities of less than 2.0 pcf required high temperature expansion using pressurized steam. Sample B was run increasing the toluene charge to 5.0%, but still could not be expanded below 4.5 pcf without pressurized steam. In Sample C, the toluene level was 5.0%, the isopentane level was 20%, and the time of impregnation was increased to 12 hours to obtain product which could be expanded at 100° C. to densities below 2.0 pcf. All results are shown in Table II.
TABLE II__________________________________________________________________________Sample No. A B C D ESECOND Make Make Make Make DoublePROCESSING Interpolymer Interpolymer Interpolymer Interpolymer InterpolymerSTEP w/Peroxide w/Peroxide w/Peroxide w/Peroxide w/PeroxidePOLYSTYRENE LEVEL 43% 43% 43% 53.5% 69%Melt Flow 29.46 33.66 25.68 29.69 14.32__________________________________________________________________________CHARGE LEVELS, %Isopentane 15 15 20 15 15Toluene 2.5 5.0 5.0 2.5 2.5Impreg. Cycle, HRS 7 7 12 7 7TOTAL VOLATILES, % 15.36 15.62 17.90 15.55 15.6655 Gallon Pre-expansion,Best Aged Density:BATCH 6.0 4.50 1.96 1.29 0.78CONTINUOUS -- -- 1.57 1.68 0.73COMMENTS/ 1.45 pcfCONCLUSIONS using pressurized steam expansion__________________________________________________________________________ | A process for producing a polypropylene-polystyrene interpolymer which can be impregnated with a blowing agent and can then be expanded under normal conditions for polystyrene particles to low density, fine cell structure foams. The interpolymer is viscbroken during the polymerization of the styrene. The polypropylene is lubricated prior to formation of the interpolymer. The process forms particles which can be impregnated with blowing agent directly. | 8 |
This is a division of application Ser. No. 955,117 filed Oct. 26, 1978, now U.S. Pat. No. 4,331,352.
INTRODUCTION
Heat exchangers incorporating apparatus of the present invention have been developed for use with large gas turbines for improving their efficiency and performance while reducing operating costs. Heat exchangers of the type under discussion are sometimes referred to as recuperators, but are more generally known as regenerators. A particular application of such units is in conjunction with gas turbines employed in gas pipe line compressor drive systems.
Several hundred regenerated gas turbines have been installed in such applications over the past twenty years or so. Most of the regenerators in these units have been limited to operating temperatures not in excess of 1000° F. by virtue of the materials employed in their fabrication. Such regenerators are of the plate-and-fin type of construction incorporated in a compression-fin design intended for continuous operation. However, rising fuel costs in recent years have dictated high thermal efficiency, and new operating methods require a regenerator that will operate more efficiently at higher temperatures and possesses the capability of withstanding thousands of starting and stopping cycles without leakage or excessive maintenance costs. A stainless steel plate-and-fin regenerator design has been developed which is capable of withstanding temperatures to 1100° or 1200° F. under operating conditions involving repeated, undelayed starting and stopping cycles.
The previously used compression-fin design developed unbalanced internal pressure-area forces of substantial magnitude, conventionally exceeding one million pounds in a regenerator of suitable size. Such unbalanced forces tending to split the regenerator core structure apart are contained by an exterior frame known as a structural or pressurized strongback. By contrast, the modern tension-braze design is constructed so that the internal pressure forces are balanced and the need for a strongback is eliminated. However, since the strongback structure is eliminated as a result of the balancing of the internal pressure forces, the changes in dimension of the overall unit due to thermal expansion and contraction become significant. Thermal growth must be accommodated and the problem is exaggerated by the fact that the regenerator must withstand a lifetime of thousands of heating and cooling cycles under the new operating mode of the associated turbo-compressor which is started and stopped repeatedly.
Confinement of the extreme high temperatures in excess of 1000° F. to the actual regenerator core and the thermal and dimensional isolation of the core from the associated casing and support structure, thereby minimizing the need for more expensive materials in order to keep the cost of the modern design heat exchangers comparable to that of the plate-type heat exchangers previously in use, have militated toward various mounting, coupling and support arrangements which together make feasible the incorporation of a tension-braze regenerator core in a practical heat exchanger of the type described.
Heat exchangers of the type generally discussed herein are described in an article by K. O. Parker entitled "Plate Regenerator Boosts Thermal and Cycling Efficiency", published in The Oil & Gas Journal for Apr. 11, 1977.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to heat exchangers and, more particularly, to apparatus for providing thermal isolation and support of heat exchanger ducting members from the heat exchanger frame.
2. Description of the Prior Art
Arrangements are known in the prior for fastening together two different elements in a heat insulating mounting or for accommodating thermal growth between adjacent elements which are mounted together. For example, the Ygfors patent, U.S. Pat. No. 3,690,705 discloses a device for rigidly connecting two metallic members together in heat-insulating relation. The arrangements disclosed in this patent depend upon a bushing constructed of a material having known heat insulating properties mounted between the two members.
The Young patent, U.S. Pat. No. 3,710,853, discloses an arrangement of a radiator comprising two headers or tanks on opposite sides of a heat exchanging core. One of the tanks is fixed to the frame while the other is mounted to the frame by means of a shoulder stud extending through an enlarged hole in the frame to permit lateral movement of the stud. However, no thermal isolation of the radiator from the mounting frame is provided, the only concern being the accommodation of the different coefficients of expansion for the frame and the radiator. The arrangement of the Young patent depends upon flexible conduits, typically rubber hoses, for connection to the fluid passages of the radiator.
Devices of the type disclosed in these prior art patents may be suitable for apparatus of limited size, weight and thermal gradient. However, they are totally unsuitable for heat exchangers of the type here involved which include heat exchanger cores operating at temperatures in excess of 1000° F. supported in frames of conventional structural steel construction maintained at temperatures less than 150° F.
SUMMARY OF THE INVENTION
In brief, arrangements in accordance with the present invention comprise members for supporting heat exchanger ducts relative to the heat exchanger frame which serve to provide thermal isolation of the ducts from the associated frame members while accommodating axial and radial thermal growth and limited lateral movement. Thermal isolation with the required structural support is provided in accordance with an aspect of the invention by the use of thin walled metal members extending between the ducts and associated points of attachment to the frame. One such element is in the form of a thin walled cylinder with end plates threaded to receive mounting bolts. The cylinder is attached to a frame member (the cold structure) by a mounting bolt fitted into one end of the cylinder. The other end of the cylinder is constrained axially by means of a shoulder bolt threaded into the other end of the cylinder and extending through an oversized opening in a flange attached to the heat exchanger duct (the hot structure). This opening may be a radially aligned slot in the flange or a round opening larger than the body of the bolt but small enough to be engaged by the bolt head or a retaining washer mounted thereon. The threaded portion of the shoulder bolt is of lesser diameter than the shoulder portion, thereby insuring sufficient space between the end of the thin walled cylinder and the retaining portion (head or washer) to permit the duct flange to slide radially relative to the cylinder. Although the cylinder is of metal for structural strength, the thin walls of the cylinder have low thermal conductivity, thus providing the desired thermal isolation between the hot and cold structures.
Further thermal isolation with accommodation of thermal growth of the hot structure is also provided by circumferential bellows members having re-entrant collar portions developing an extended path length for heat travelling through the metal between the hot and cold structures. Duct flange members at opposite ends of the heat exchanger are provided for supporting the duct loading of attached piping and for balancing the internal pressure forces relative to the frame. These are tied together for dimensional stabilization of the heat exchanger by means of tie rods which extend through the space surrounding the heat exchanger core. Support pins extending through openings in ears or projections on the manhole flanges covering the blind ducts at the rear end of the heat exchanger serve to support these flanges and ducts while permitting several inches of axial growth of the core structure and internal duct passages connected thereto.
BRIEF DESCRIPTION OF THE DRAWING
A better understanding of the present invention may be had from a consideration of the following detailed description, taken in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective, partially exploded view of a heat exchanger module in which embodiments of the present invention are utilized;
FIG. 2 is a perspective view of the heat exchanger module of FIG. 1, taken from the opposite end;
FIG. 3 is a sectional view of a portion of the heat exchanger module of FIGS. 1 and 2, illustrating one embodiment of the invention;
FIG. 4 is a view, partially broken away, taken along the line 4--4 of FIG. 3 and looking in the direction of the arrows;
FIG. 5 is a sectional view of a portion of the module of FIGS. 1 and 2, showing details of another embodiment of the present invention; and
FIG. 6 is a sectional view of another portion of the module of FIGS. 1 and 2, showing details of still another arrangement in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As presently constructed, heat exchangers utilizing arrangements in accordance with the present invention are fabricated of formed plates and fins assembled in sandwich configuration and brazed together to form core sections. These sections 10 are assembled in groups of six (referred to as "six-packs") as shown in FIGS. 1 and 2 to form a core 12 which, together with associated hardware, comprises a single heat exchanger module 20. A single module 20 may be joined with one or more other modules to make up a complete heat exchanger of desired capacity.
In the operation of a typical system employing a regenerator of the type discussed herein, ambient air enters through an inlet filter and is compressed to about 100 to 150 psi, reaching a temperature of 500° to 600° F. in the compressor section of an associated gas turbine (not shown). It is then piped to the regenerator module 20, entering through the inlet flange 22a (FIG. 1) and inlet duct 24a. In the regenerator module 20, the air is heated to about 900° F. The heated air is then returned via outlet duct 24b and outlet flange 22b to the combustor and turbine section of the associated turbine via suitable piping. The exhaust gas from the turbine is at approximately 1100° F. and essentially ambient pressure. This gas is ducted through the regenerator 20 as indicated by the arrows labelled "gas in" and "gas out" (ducting not shown) where the waste heat of the exhaust is transferred to heat the air, as described. The exhaust gas drops in temperature to about 600° F. in passing through the regenerator 20 and is then discharged to ambient through an exhaust stack. In effect, the heat that would otherwise be lost is transferred to the inlet air, thereby decreasing the amount of fuel that must be consumed to operate the turbine. For a 30,000 hp turbine, the regenerator heats 10 million pounds of air per day.
The regenerator is designed to operate for 120,000 hours and 5000 cycles without scheduled repairs, a lifetime of 15 to 20 years in conventional operation. This requires a capability of the equipment to operate at gas turbine exhaust temperatures of 1100° F. and to start as fast as the associated gas turbine so there is no requirement for wasting fuel to bring the system on line at stabilized operating temperatures. The use of the thin formed plates, fins and other components making up the brazed regenerator core sections contributes to this capability. However, it will be appreciated that there is substantial thermal growth in all three dimensions as a result of the extreme temperature range of operation and the substantial size of the heat exchanger units. As an example, the overall dimensions for the module 20 shown in FIGS. 1 and 2, in one instance, were 17 feet in width, 12 feet in length (the direction of gas flow) and 7.5 feet in height.
The core 12 is suspended from beams 16 by a suspension system which permits this thermal growth. Also, coupling is provided between the manifold duct portions 24a, 24b and the inlet and outlet flanges 22a, 22b by apparatus which isolates the external pipe loads at the flanges 22a, 22b from the heat exchanger core 12 while accommodating the thermal growth as described.
As indicated, particularly in FIG. 2, somewhat similar flange and duct arrangements are provided at the end of the module 20 opposite the air flanges 22a, 22b and ducts 24a, 24b. These comprise blind ducts such as 26 (FIG. 1) and manway flanges 28a, 28b with manhole covers 30a, 30b, and are provided for balancing the internal pressure forces on the manifold portions of the core 12 by means of tie rods 36 and to permit access to the manifold sections of the core 12 for inspection and maintenance.
The frame is maintained in thermal isolation from the heat exchanger core 12 and associated components which are operated at elevated temperatures to levels in excess of 1000° F. in a manner which insures that the temperature of the frame will not exceed 140° on a 100° day, thus permitting the frame to be constructed of low-cost structural steel while limiting the requirement for special high temperature materials essentially to the heat exchanger core 12.
It will be appreciated that the highest temperature in the module 20 is at the gas inlet side of the chamber surrounding the core 12. This chamber is thoroughly insulated by blankets and blocks of insulation, such as the insulation blanket 34 (FIG. 2). While this chamber contains exhaust gas at a pressure at or slightly above ambient, it will be appreciated that all parts of the frame 32 must be protected against possible leaks past the thermal blanket insulation 34 which might permit hot exhaust gas to escape and reach any portion of the frame 32.
The flanges 22a, 22b are fixed in position relative to the frame 32 and thermal growth is permitted to extend in the direction from left to right in the module as shown in FIG. 1. The pressure forces developed by the compressed air within the manifold portions of the core 12 are contained by tie rods 36 which extend through the gas chamber and fasten at opposite ends to the flanges 22a, 22b, 28a, and 28b as shown. However, since these tie rods 36 are of substantial length, approximately 18 feet, with the major portion of their length extending within the hot exhaust gas chamber, the tie rods 36 also experience thermal growth and provision must be made to accommodate this growth at the blind duct/manway flange end of the module 20 while providing the necessary support from the frame 32 of the weight of the structure at that end.
As noted above, the air leaving the regenerator module 20 through outlet flange 22b is at approximately 900° F. Thus the flange 22b is also close to this temperature. The flange is mounted to the adjacent structure of the frame 32 by means of thermal isolators 40, such as are shown in FIG. 3. Four such thermal isolators 40 are provided for each of the flanges 22a and 22b, spaced approximately 90° apart about the flanges 22a, 22b.
As particularly shown in FIGS. 3 and 4, the thermal isolator 40 comprises a thin-walled cylinder 42 fastened to end portions 44, 45, as by brazing or welding. The end portion 44 is threaded to receive a mounting bolt 46 extending through a frame member 48 and a plate 49 welded to the frame member 48. This is the cold end of the thermal isolator 40 and is rigidly affixed to the frame.
At the opposite end of the thermal isolator 40, the closed end portion 45 is threaded to receive a shoulder bolt 50 having a shoulder portion 52 which bears against the end portion 45 as the bolt 50 is threaded into the end portion 45 and prevents further tightening of the bolt 50 in the threaded opening, thus maintaining a selected minimum spacing between the head of the bolt 50 and the end portion 45.
The flange 22 is provided with a slotted projection or ear 54 (FIG. 4) to receive the bolt 50. The minimum spacing between the head of the bolt 50 and the thermal isolator end portion 45 is sufficiently greater than the thickness of the ear 54 at this point to accommodate a washer 56 and maintain a gap of not less than 0.005 inches. Moreover, the positioning of the thermal isolator 40 on the frame member 48 relative to the flange 22 is such that a radial gap 58 of not less than 0.20 inches is maintained. This arrangement provides the desired support of the flange 22 with thermal isolation relative to the frame member 48 while accommodating radially directed thermal growth of the flange 22. That is, the flange 22 may expand radially outward to reduce the gap 58 as the flange 22 rises in temperature while the ear portion 54 slides relative to the bolt 50 and washer 56. Similar movement in the reverse direction is permitted as the flange 22 cools down after shutdown of the associated turbine.
Referring to FIG. 5, this is a sectional view taken in the vicinity of the circle inset in FIG. 2. It shows a support arrangement 60 for supporting the manway flange 28b while accommodating thermal growth from the longitudinal expansion of the tie rods 36. This support arrangement 60 is represented in FIG. 5 as comprising a support pin 62 mounted on a frame member 64. A slotted extension 66 of the manway flange 28b encompasses the support pin 62 and moves outwardly (to the left) along the support pin 62 as the tie rods 36 extend in length due to thermal growth. Four such support arrangements 60 are provided for each of the flanges 28a, 28b, spaced at approximately 90° intervals about the periphery of the flange. Radial thermal growth is accommodated in a fashion similar to the forward end although temperature differences are somewhat less.
Also shown in FIG. 5 is a portion of the blind duct 26 suspended within a circumferential duct housing 70. The exterior surface 72 of the circumferential housing 70 is exposed, about its right-hand end as shown in FIG. 5, to the interior gas chamber of the module. A frame member 74 is shown adjacent this exterior surface 72 and insulation, such as the insulation 34 (FIG. 2), is placed in this region, but it has been omitted in FIG. 5 for simplicity. The space between the frame member 74 and the duct housing surface 72 is sealed by the circumferential member 76 which is shown comprising a bellows portion 78 and a collar portion 80. The collar portion 80 is a thin sheet fastened to the exterior surface 72 at one end and attached to the metal corrugated or bellows portion 78 at its other end. The bellows portion is joined to the frame member 74 at an end remote from its juncture with the collar portion 80. With the configuration as shown, the sealing member 76 provides thermal isolation between the duct housing surface 72 and the frame member 74 by virtue of being of thin metal cross-section and extended path length for heat which may be carried by this member. At the same time, the bellows portion 78 permits the member to accommodate the movement of the duct housing due to thermal growth of the tie rods 36. It also serves to accommodate radial thermal growth of the duct housing 70 and its external surface 72 as well as a certain amount of transverse displacement of the duct 26 and duct housing 70 relative to the axis thereof, all without any disruption of the sealing function performed by this thermally isolating, sealing member 76.
A similar arrangement, shown in FIG. 6, is provided for the air ducts 24a, 24b at the other end of the heat exchanger core 12. FIG. 6 is a sectional view comparable to the view of FIG. 5, but depicting an air duct 24 with its suspension housing 81 and external housing surface 82. The space between adjacent frame member 84 and the external surface 82 is sealed with a thermally isolating sealing member 86 which is shown comprising a corrugated or bellows portion 88 and a wishbone-shaped portion 90 formed of a pair of conical sheets 92 and 94. The member 86 is a circumferential structure which encircles the duct 24 and the duct housing 81 with the plate 94 being attached at one edge to the exterior housing surface 82. Member 86 accommodates axial movement of the duct housing 82 relative to the frame member 84 as well as axial displacement and radial growth of the duct 24 and duct housing 81, while at the same time maintaining the desired thermal isolation between the hot structure of the surface 82 and the frame member 84 by virtue of the extended path length of the member 86.
As thus described, the arrangements in accordance with the present invention advantageously provide support with thermal isolation of various portions of a heat exchanger which is subject to extreme operating temperatures and repeated cycling between full operation and shutdown. The thermal isolation afforded by these arrangements in accordance with the present invention is such that the associated frame structure is maintained below a maximum temperature of approximately 140° F., well within acceptable temperatures for any metal suitable as frame structure. Particular thermal isolators in accordance with the present invention serve to transmit support loads from a hot component to the cold support structure. The isolator reduces the temperature rise, and the attendent decrease in strength, of the cold structure using a thin-walled cylinder of low thermal conductivity to restrict heat flow. These arrangements in accordance with the invention are adapted to accommodate thermal growth and anticipated displacement of the hot structures being supported, relative to the associated support frame members.
Although there have been shown and described herein specific arrangements of a heat exchanger support system providing for thermal isolation and growth in accordance with the invention for the purpose of illustrating the manner in which the invention may be used to advantage, it will be appreciated that the invention is not limited thereto. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art should be considered to be within the scope of the invention as defined in the appended claims. | Apparatus for supporting and constraining opposed end members of a heat exchanger frame structure while maintaining the high temperature portions of the heat exchanger thermally isolated from the frame and accommodating relative movement of the heat exchanger due to thermal growth. Thermal isolation with structural support is achieved by the use of strategically positioned, thin-walled metal members aligned in the direction of heat travel between high temperature portions of the heat exchanger and adjacent frame elements. Opposed portions of the heat exchanger are tied together by rods extending between them and secured thereto. Longitudinal growth of the heat exchanger core and associated ducting is accommodated by the provision of flange guides slidable on guide pins attached to the frame. | 5 |
FIELD OF THE INVENTION
The invention relates generally to ribbon cartridges for use in typewriters and/or printers employed in word processors, line printers, and the like, and is more particularly related to improved ribbon tensioning and locking of such cartridges.
BACKGROUND OF THE INVENTION
Ribbon cartridges containing inked ribbons for use in powered typewriters and the like, have gained wide acceptance because of the ease of installing such cartridges and because of their inherent cleanliness. Often, such ribbons are of the single pass type, i.e., are not reuseable, wherein the cartridge is, after use, discarded. To manufacture such disposable cartridges which reliably serve their purpose at an economical price is a challenge. With the emergence of higher and still higher speed typewriters/printers, the physical demands made on such cartridges are increasing and the problem of making an economical and reliable cartridge is compounded.
Among the problems encountered in ribbon cartridges is that of maintaining the span of ribbon external to the cartridge at a desired length. If too much ribbon were present, it could become ensnarled with the typing/printing mechanism. To prevent this from happening, provision for stopping or braking both the supply and takeup must be provided. One advantageous method of achieving this is described in U.S. Pat. No. 4,013,160, assigned to A. B. Dick Company, the assignee of the present invention, which patent issued on Mar. 22, 1977, in the names of Paul S. Colecchi, the present inventor, and Cezary Kotecki. The present invention, although capable of a broader application, will be described in the environment of the cartridge described and claimed in that patent.
While constant friction, even aided by spring pressure, may be adequate in some applications, such as shown in U.S. Pat. No. 3,974,906, the increased stress and vibrations resulting occasionally on higher speed powered typewriters and the like, as, for example, result from a full carriage return, make this approach unacceptable. The force necessary to hold the ribbon under these circumstances (which must be overcome to advance it) would require an excessively thick or strong ribbon or would run the danger of breaking or tearing the ribbon.
While mechanical hub rims and lever interlocks, such as shown in U.S. Pat. No. 4,010,839, may be effective, they do not necessarily prevent overruns of a supply spool caused by tightening of the ribbon on its hub, and they require provisions of extra and relatively expensive parts.
SUMMARY OF THE INVENTION
The present invention provides for a ribbon cartridge of the type that may be used in a powered typewriter or the like, which cartridge includes the improvement of a tensioning and locking apparatus between the ribbon supply and its exit from the cartridge which includes a mechanically biased movable member that bears against the ribbon to hold the ribbon outside span in tension and to absorb small overruns of supplied ribbon during normal use and automatically moves so as to releaseably lock the ribbon by sandwiching it between the movable member and at least one fixed element when the supply overruns ribbon toward the exit.
The invention, together with the advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawing, in the several figures of which like reference numerals identify like elements.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a sectional, plan view of a ribbon cartridge constructed in accordance with the principles of the present invention;
FIG. 2 is a view similar to that of FIG. 1, showing parts of the cartridge of FIG. 1 in moved position; and
FIG. 3 is a perspective view of one part of the cartridge of FIGS. 1 and 2 with a moved position shown in phantom outline.
DETAILED DESCRIPTION
Referring to FIG. 1, there is depicted a ribbon cartridge 10 for use with a typewriter and/or printer such as that employed with a word processor, which cartridge is constructed in accordance with the principles of the present invention.
The cartridge 10 includes a housing, generally indicated by the number 12 which is preferably constructed of molded hard plastic. The housing 12 includes sidewalls 16 which may be molded in a unitary manner with a flat bottom wall 14 to extend to a covering upper wall (not shown). A pair of spaced outwardly extending arm portions 17 and 19 are formed integrally as a part of the cartridge housing 12. A gap 21 provided therebetween permits the reception therein of a type element employed in a variety of typewriters and/or printers with which the ribbon cartridge 10 as shown is designed for use. The arms 17, 19 aid in mounting the ribbon 30 onto the ribbon lifter assembly (not shown) employed in such typewriters and printers for raising and lowering the ribbon 30 during printing.
A pair of spindles 18 and 20 (which are part of the typewriter) extend upwardly from the lower wall 14 of the cartridge housing 12 to engage ribbon supply and take up spools 22 and 24, respectively. The ribbon spools 22, 24 each include a central hub such as 26 and 28, mounted on the spindles 18 and 20, respectively, for rotation. The supply spool 22 is wound with ribbon 30 which is to be incrementally transferred therefrom to the takeup spool 24 during the printing process. The ribbon 30 extends from the supply spool 22 about rollers such as 32 and 34, out of the cartridge 10 through arm portion 17, through an exit 17E, over a guide 36, across the gap 21, over a guide 38 formed on arm portion 19, into the cartridge housing 12 through an entrance 19E at the end of arm portion 19, about a roller 40, a drive assembly 44, another roller 42, and onto hub 28 of the takeup spool 24.
The sidewalls 16, upper wall, lower wall 14, and hubs 26, 28 define an enclosed space from which the ribbon 30 leaves at exit 17E and into which it is received at entrance 19E. In use, a printing mechanism (not shown) positioned within gap 21 types or prints through the ribbon 30 to a paper suitably supported on the other side of the ribbon 30 away from gap 21.
The capstan and idler wheel ribbon drive assembly 44 is provided in the housing mounted on the lower wall 14 thereof. The capstan 46 is driven rotatably by cooperating instrumentalities in the typewriter or printer to which the capstan 46 is coupled upon installation of the cartridge 10 in the printer. The ribbon 30 passes between the capstan 46 and idler wheel 48 and is held tightly thereby so that upon rotation of the capstan 46, the ribbon 30 is moved in the direction of arrow 50.
As the ribbon 30 is driven incrementally by the capstan 46, the ribbon 30 is transferred from supply spool 22 to makeup spool 24. The particular ribbon 30 is of the type which passes only once between the supply and takeup spools 22, 24 during use. Thereafter, the cartridge 10 is discarded. This type of ribbon 30 is referred to as a single pass ribbon.
A slip drive belt 52 shown in dotted lines is provided to insure the rotation of the takeup spool 24 during the transfer of the ribbon 30. As the capstan 46 is rotated to drive the ribbon 30, the belt 52 rotates the hub 28 on spindle 20. The belt 52 is permitted to slip because as additional ribbon 30 is wound onto the take-up spool 24 the amount of movement required by the spool 24 to accept the length of ribbon 30 transferred by the rotation of the capstan 46 changes. Thus, if the belt 52 slips, no spilling or breakage of the ribbon 30 occurs because of under or over driving of the spool 24.
To provide a uniform tension on the ribbon 30 throughout its movement between the supply spool 22 and takeup spool 24, regardless of the amount of ribbon 30 present on either spool 22, 24, there is provided the ribbon tensioning device 54. This type of tensioning device is described in detail and claimed in the aforementioned U.S. Pat. No. 4,013,160, and reference may be had to that patent for a fuller description.
In accordance with the present invention, ribbon tensioning and locking apparatus 55 is provided astride the path of the ribbon 30 between the supply spool 22 and the exit 17E. The apparatus 55 includes a member 60. The ribbon 30 passes around one end of the member 60, between that member 60 and a post 62. The member 60 is secured at one end 64 to the interior of sidewall 16, at the area 16A by being sandwiched between the interior of the sidewall area 16A and a second parallel wall section 16B.
The member 60 extends in a cantilever fashion from the end of wall 16B and in normal use is, as shown in FIG. 1, more or less straight, and has the ribbon 30 turning about its free end 66 at about a right angle.
The member 60 is mechanically biased by being made of spring steel or other acceptable spring material and, serves in normal use, to absorb small overruns and to properly tension the span of the ribbon 30 that bridges the gap 21 between the exit 17E and entrance 19E. That is, as the ribbon drive 44 starts up the spring 60 deflects upward to absorb the takeup of ribbon 30 until the inertia of the spool 22 can be overcome. Similarly, upon stoppage of the intermittent drive 44, the spring 60 relaxes somewhat to take up any small overrun caused by the inertia of the moving spool 22.
In the case of unusual overrun, as for example might occur because of vibration in a high speed machine during carriage return or spacing (during which time the drive mechanism 44 keeps the ribbon 30 around it stationary), the spring member 60 relaxes more due to the continued unwinding of ribbon 30 from the supply spool 22 and clamps and sandwiches the ribbon 30 between itself and the post 62, as shown in FIG. 2. For this purpose, the member 60 is provided with a permanent bend or bight 68 which when in the position of FIG. 2, conforms to the shape of the post 62.
The member 60 is arcuately shaped at 69 (as can be seen from FIGS. 2 and 3) to conform to the periphery of roller 32 so that in the usual operating position there is clearance between the member portion 69 and the roller 32. That assures that the bend 68 of the member 60 is free to be urged against post 62 and clamp the sandwiched ribbon 30 or tape.
Further, it should be noted that the end 66 of the member 60 in its relaxed state (FIG. 2) lies within the outer boundary 22' of the fully wound supply spool 22 and thus, also serves to bear against and clamp the unused ribbon 30 against the spool 22 to even more securely hold the ribbon 30 in place. This aids in preventing unwanted unraveling of the ribbon 30 from the supply spool 22 during shipping and handling prior to use on a typewriter or the like. When normal operating conditions are resumed and the ribbon drive 44 becomes active, the preset tension of the spring member 60 meters out the correct amount of ribbon 30 to maintain proper tension until all of the unwound material is used up causing the spool 22 tensioning device 54 to operate and the spring member 60 to assume the normal deflected position of FIG. 1.
It should be noted that the passage from one state to the other is achieved smoothly and without any interruption or outside interference.
It should now be apparent that a novel ribbon cartridge 10 with improved tensioning and locking provision has been described and depicted. The tensioning and locking features of the invention employs a single moving part, the mechanically biased member 60, and yet achieves a positive and continuous and automatic function of tensioning and locking of the ribbon 30 against overrun. Thus, it provides the advantages of ease of operation and assembly, as well as economy of parts and simplicity with the inherent savings in maintenence and repair that result therefrom.
While one particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention. | A ribbon cartridge for use in a typewriter and/or printer which cartridge has a supply of ribbon which is fed from within the cartridge across a gap where it is used by a typing or printing mechanism and returned to a driven take-up area, is disclosed, which cartridge includes an improved tensioning and locking apparatus, comprising a mechanically biased movable member positioned between the ribbon supply and its outlet, so as to bear against the ribbon, which member automatically takes up small overruns of ribbon from a supply and releasably locks the ribbon by means of friction contact when large overruns occur during use. | 1 |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/546,911, filed Oct. 13, 2011, and which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a spray mop, and more particularly to a spray mop in which the pattern of spray dispensed can vary.
BACKGROUND OF THE INVENTION
Remotely activated sprayers are known. For example, U.S. Pat. Nos. 4,432,472, 5,368,202, 6,976,644 and 7,040,510 disclose mounting spray devices on one end of a shaft and remotely activating the spray device from the other end of the shaft. The U.S. Pat. No. 4,432,472 discloses a buffer at the distal end of the shaft, along with a chain connected thereto that extends to the proximate end of the shaft for operating the spray device remotely. The U.S. Pat. Nos. 5,368,202, 6,976,644 and 7,040,510 disclose a trigger lever at the proximal end (i.e. user's handle end) of the shaft, which when activated (moved) by the user causes the spray device at the other end of the pole to emit a liquid spray. The use of such trigger levers to remotely trigger a spray device at the other end of the shaft which also contains a cleaning device such as a broom or mop is also known (i.e. spray mop).
One issue with conventional spray mops is the user's need to control the pattern of spray emitted by the spray device each time the lever is activated. For some applications, the user may wish to use a narrow, focused pattern. For other applications, the user may wish to use a wide, dispersed pattern. For still other applications, the user may wish to use both. Conventional spray devices include a pattern adjustment, but they typically utilize a single nozzle (with adjustments made to that single nozzle), with mixed results in terms of quality of spray pattern, reliability, ease of use, and ease of manufacture.
There is a need for a convenient adjustment mechanism for adjusting the pattern of liquid that is released by the spray device, which is reliable, easy to use, and easy to manufacture.
BRIEF SUMMARY OF THE INVENTION
The aforementioned problems and needs are addressed by a sprayer assembly that includes a reservoir for storing liquid, a pump in fluid communication with the reservoir, first and second supply tubes in fluid communication with the pump wherein the pump is configured to draw liquid from the reservoir and discharge the liquid into the first and second supply tubes, a first nozzle in fluid communication with the first supply tube, a second nozzle in fluid communication with the second supply tube, and a collar having at least one protrusion and rotatable between a first position in which the at least one protrusion pinches closed the first supply tube but not the second supply tube, and a second position in which the at least one protrusion pinches closed the second supply tube but not the first supply tube.
In another aspect of the present invention, a sprayer assembly includes a reservoir for storing liquid, a pump in fluid communication with the reservoir, an output tube in fluid communication with the pump wherein the pump is configured to draw liquid from the reservoir and discharge the liquid into the output tube, first and second supply tubes in fluid communication with the output tube, a first nozzle in fluid communication with the first supply tube, a second nozzle in fluid communication with the second supply tube, and a collar having first and second protrusions and rotatable between a first position in which the first protrusion pinches closed the first supply tube, and a second position in which the second protrusion pinches closed the second supply tube.
Other objects and features of the present invention will become apparent by a review of the specification, claims and appended figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the spray mop.
FIG. 2A is a perspective view of the interior of the handle assembly, with the rod positioned on the engagement surface for high volume spray.
FIG. 2B is a perspective view of the interior of the handle assembly, with the rod positioned on the engagement surface for low volume spray.
FIG. 3A is a side view of the interior of the handle assembly, with the rod positioned on the engagement surface for high volume spray.
FIG. 3B is a side view of the interior of the handle assembly, with the rod positioned on the engagement surface for low volume spray.
FIG. 4A is a perspective view of the interior of the handle assembly, with the rod positioned on the engagement surface for high volume spray.
FIG. 4B is a side view of the interior of the handle assembly, with the rod positioned on the engagement surface for high volume spray.
FIG. 5A is a perspective view of the interior of the handle assembly, with the rod positioned on the engagement surface for low volume spray.
FIG. 5B is a side view of the interior of the handle assembly, with the rod positioned on the engagement surface for low volume spray.
FIG. 6 is a side view of the interior of the spray device assembly.
FIG. 7 is a rear view of the rotatable collar.
FIG. 8 is a rear view of the rotatable collar, support block and supply tubes.
FIG. 9 is a rear view of the rotatable collar and support block.
FIG. 10 is a rear view of the rotatable collar, support block and supply tubes.
FIG. 11 is a rear view of the rotatable collar and support block.
FIG. 12 is a partial rear view of the rotatable collar.
FIGS. 13-14 are front views of the rotatable collar and spray nozzles.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a spray mop, as shown in FIG. 1 . The spray mop includes a shaft 12 terminating at a proximal end with a handle assembly 14 and at a distal end with a cleaning element 16 . A spray device assembly 18 is mounted to the shaft 12 closer to the distal end of shaft 12 .
The handle assembly 14 include a lever 20 that is rotatable (i.e. by a user) about a pivot point 22 , as best illustrated in FIGS. 2A and 2B . The lever 20 includes multiple concave engagement surfaces 24 (two such surfaces 24 a and 24 b illustrated in the figures). A rod 26 is slidably mounted in shaft 12 , and selectively engages with engagement surfaces 24 a / 24 b . When the user rotates lever 20 , the lever 20 pushes on rod 26 , causing rod 26 to slide toward the distal end of shaft 12 (to operate the spray device assembly as described below).
The handle assembly 14 includes a mode control knob 28 that dictates the amount of longitudinal movement the rod 26 experiences as the user rotates lever 20 through its full range of motion (and thus dictates the volume of liquid sprayed during a single operation of the lever). Specifically, the mode control knob 28 controls the position of engagement of the rod 26 on the lever 20 (i.e. which concave engagement surface 24 a / 24 b is engaged with rod 26 ). The mode control knob 28 has a cam surface 30 that engages with the side surface of rod 26 . When the control knob 28 is rotated, the cam surface transversely moves the proximal end of rod 26 between engagement surface 24 a and engagement surface 24 b. With the mode control knob 28 rotated to its low spray volume position (see FIGS. 2B, 3B, 5A, 5B ), the proximal end of the rod 26 is positioned on engagement surface 24 a , which is closer to pivot point 22 and thus results in a smaller longitudinal displacement of the rod 26 (for a smaller volume of spray) as the lever 20 is moved through its range of motion. With the mode control knob 28 rotated to its high spray volume position (see FIGS. 2A, 3A, 4A, 4B ), the proximal end of the rod 26 is positioned on the engagement surface 24 b , which is further away from pivot point 22 and thus results in a greater longitudinal displacement of the rod 26 (for a greater volume of spray) as the lever 20 is moved through the same range of motion.
The distal end of rod 26 is aligned to and operates a pump 32 as it is longitudinally moved by lever 20 , as shown in FIG. 6 . Pump 32 includes a plunger 33 that, when compressed by the longitudinal movement of rod 26 , draws liquid from a reservoir 34 via intake tube 36 , and discharges the liquid into output tube 38 . The amount of liquid discharged is a function of the displacement of the pump plunger (and therefore a function of the movement of rod 26 ). The discharged liquid is delivered to discharge jets as described below that spray liquid from assembly 18 and to the area being cleaned.
The liquid is consistently and continually discharged by pump 18 (and therefore consistently and continually sprayed from assembly 18 ) throughout the entire travel of the lever 20 . However, the volume of liquid discharged and sprayed through that single activation of the lever 20 can be varied by operating the mode control knob 28 without changing the fact that liquid is being continuously sprayed (i.e. the amount of lever arm travel need not be changed, just the rate/volume of liquid being sprayed during the travel). Additionally, the amount of spray volume can be adjusted at the handle assembly 14 , instead of down at the sprayer device assembly, which is convenient for the user. While the preferred embodiment includes two positions of the rod engagement on the handle lever as dictated by the mode control knob (i.e. two concave engagement surfaces 24 a / 24 b ), there could be more than two positions if desired.
As illustrated in FIG. 6 , a one-way valve 40 is disposed along output tube 38 . Output tube 38 then divides into or is coupled to two separate supply tubes 42 and 44 each made of soft compressible tubing. The supply tubes 42 / 44 each terminate at a spray nozzle 46 or 48 . Spray nozzles 46 and 48 have spray patterns that differ from each other (e.g. narrow stream and horizontally extending spray). While the preferred embodiment has two supply tubes and two nozzles, more than two supply tubes and nozzles can be used.
While both supply tubes 42 / 44 are pressurized with liquid by the operation of pump 32 , the operation of nozzles 46 / 48 can be selectively blocked. Specifically, a rotatable collar 50 is used to selective pinch and occlude one of the supply tubes 42 / 44 , thereby selecting the other supply line and associated nozzle for use. Therefore, as illustrated in FIG. 6 , supply tube 44 is pinched by collar 50 , thereby preventing liquid from reaching nozzle 48 . With the collar rotational position of FIG. 6 , liquid only dispenses from nozzle 46 when pump 32 is operated.
The collar 50 is best illustrated in FIG. 7 . It contains two inwardly facing tube compression protrusions 52 and 54 , which selectively pinch closed the supply tubes 42 / 44 . In FIGS. 8 and 9 , the collar 50 is rotated to a first rotational position so that protrusion 52 pinches closed the supply tube 44 (i.e. against a rounded compression surface 56 of a support block 58 adjacent the supply tube 44 ). In this first rotation position, the liquid from pump 32 is supplied only to nozzle 46 of supply tube 42 . In FIGS. 10 and 11 , the collar 50 is rotated to a second rotation position so that protrusion 54 pinches closed the supply tube 42 (i.e. against a rounded compression surface 60 of support block 58 adjacent the supply tube 42 ). In this second rotation position, the liquid from the pump 32 is supplied only to nozzle 46 of supply tube 44 .
In a preferred embodiment as shown in FIG. 12 , each tube compression protrusion 52 / 54 includes a straight leading edge 62 that terminates in a rounded end 64 (that matches the rounded shape of the corresponding rounded compression surface 56 / 60 of the support block 58 ). The rounded end 64 extends out slightly from the leading edge 62 and toward the supply tube 42 / 44 that it will pinch. It has been discovered that this shape is ideal for effectively pinching and sealing the supply tube 42 / 44 without dislodging or otherwise damaging the supply tube. Bumps 66 can also extend from the collar as shown in FIG. 12 , where the bumps 66 engage complementary notches, holes or channels to provide tactile feedback to the user that the collar 50 is properly positioned to pinch closed the desired supply tube.
FIGS. 13 and 14 illustrate the two preferred nozzle types. The upper nozzle 48 has a narrow opening for creating a narrow output stream. The lower nozzle 46 has an elongated opening for creating a horizontally elongated output stream. Collar 50 can include a tab 68 extending therefrom to assist the user in rotating the collar 50 , and for visually indicating the rotational position of the collar 50 . Collar 50 is preferably rotatably supported by or connected to support block 50 . However, collar 50 could alternately be rotatably supported by or connected to housing 19 of spray device assembly 18 .
It is to be understood that the present invention is not limited to the embodiment(s) described above and illustrated herein, but encompasses any and all variations falling within the scope of the appended claims. For example, references to the present invention herein are not intended to limit the scope of any claim or claim term, but instead merely make reference to one or more features that may be covered by one or more of the claims. Materials, processes and numerical examples described above are exemplary only, and should not be deemed to limit the claims. A single protrusion can be used instead of two protrusions 52 / 54 to selectively pinch tubes 42 / 44 . In the case of a single protrusion, or in the case with the proper spacing between protrusions 52 / 54 , the user could rotate the collar to an intermediate rotation position (between the first and second rotation positions), where neither supply tube 42 / 44 is pinched, and thus both nozzles 46 / 48 can be operated simultaneously to provide two streams at the same time. Lastly, while two nozzles, two supply lines and two rotational positions are shown and described above, it is within the scope of the present invention to include three or more nozzles, supply lines and collar rotational positions. | A sprayer assembly that includes a reservoir for storing liquid, a pump in fluid communication with the reservoir, first and second supply tubes in fluid communication with the pump wherein the pump is configured to draw liquid from the reservoir and discharge the liquid into the first and second supply tubes, a first nozzle in fluid communication with the first supply tube, a second nozzle in fluid communication with the second supply tube, and a collar having at least one protrusion and rotatable between a first position in which the at least one protrusion pinches closed the first supply tube but not the second supply tube, and a second position in which the at least one protrusion pinches closed the second supply tube but not the first supply tube. | 0 |
FIELD OF THE INVENTION
The present invention relates to apparatus useful in the casting of molten metal and more particularly to such devices as are utilized in the casting of so-called “logs”, “billet” or “round ingots” from, for example, molten aluminum.
BACKGROUND OF THE INVENTION
In the casting of molten metals such as aluminum apparatus and processes have been developed for the simultaneous casting of a plurality of logs, billets or round ingots, hereinafter logs, so as to increase the efficiency and productivity of the casting processes. In such processes and apparatus, a casting table having a plurality of apertures or molds is mounted over a pit from which emerge an equally numbered plurality of hydraulically operated bottom blocks. Each of the bottom blocks is registered, i.e. aligned with, one of the molds. The casting table includes troughs or distribution channels for the dissemination of molten metal introduced thereto to each of the individual molds or apertures located in the casting table. As metal from the distribution channels or troughs in the casting table enters the individual molds, the plurality of bottom blocks is lowered in unison to allow for removal of metal that has solidified in the mold therefrom and to provide space for the introduction of additional incoming molten metal. Such a prior art casting table is shown in FIG. 1 and described in greater detail hereinafter.
While the metal distribution of the casting tables of the prior art as depicted in FIG. 1 have proven highly useful and reliable over many years of service in a multitude of installations, they suffer a number of shortcomings.
As those skilled in the molten metal casting arts are well aware, it is critically important that molten metal reaching each of the molds or apertures at substantially the same time with minimal temperature loss to obtain a successful cast of the plurality logs being simultaneously cast. If metal reaching one or more apertures is too hot or hold time is too short and does not solidify as the base plate descends, a “bleedout” can result. In such a condition, molten metal can be brought into contact with water applied as a spray in the process to cool the solidifying metal. Such a conditions requires rapid plugging of the aperture or mold that is experiencing the “bleedout” with the result that that portion of the production is lost for the cast. Alternatively, if metal has resided in the mold for too long a period, it may be cooler than the balance of the molten metal and therefore solidify more quickly in the mold than metal entering other molds in the casting table resulting in a “freeze-in”, i.e. the solidified metal becomes caught in the mold. Freeze in can drop out during casting and also result in bleedout. Such a condition can result the aborting of the cast entirely and necessitating a freeing up of the metal caught in the mold and a restart of the cast. Such errors can cause significant productivity losses and place operators in significant danger from a safety standpoint. If metal enters the mold with too much velocity or too hot, penetrates between the mold and the head, solidified ingot head “flashing” may occur. Flashing is another condition that may result in molten metal coming into contact with cooling water applied to the ingot below the solidification point. Flashing also causes damage to molds or distortion or delays in the bottom block movement that can also result in casting defects, bleedouts or complete table freeze in.
In addition to the foregoing, as will be explained in greater detail below, the design of the prior art “dams”, i.e. barriers that control the flow of molten metal into the distribution troughs within the casting table, often required the presence of at least two operators on the casting table at the initiation of a casting drop to “lift” or remove the dams at the start of the cast. The presence of operators in the immediate vicinity of the molten metal casting operation is always a safety concern, and the ability to eliminate the exposure of operators to such a risk is critically important to casting facilities.
Finally, the mold portions of the prior art casting tables comprise multi-part elements that require assembly in the casting table costing valuable assembly or set-up time and which because of their design leave exposed joints between the individual elements of the assembly that are sometimes prone to leaking, particularly if not properly assembled.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to provide a multi-strand metal distribution system that provides more uniform molten metal distribution at the start of a cast, minimizes heat loss and controls the velocity and fill time differences of molten metal entering the molds.
It is another object of the present invention to provide a thimble assembly for the above-described multi-strand metal distribution systems that because of their design and construction provide simplified and more secure installation of the mold assemblies.
It is yet another object of the present invention to provide a metal distribution system that incorporates an improved dam release mechanism that obviates the need for the presence of operators on the casting table to release dams during start up of a cast.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a metal distribution system for the simultaneous production of a plurality of logs or round billets from molten metal comprising: 1) a single main trough for the introduction of molten metal; 2) a plurality of side streams extending from the trough and each of the side streams including a plurality of opposing pairs of apertures each of the apertures including a mold for the shaping of molten metal passing through the trough and the side streams and into the molds. A controlled velocity and uniform flow of molten metal into the side streams and the individual apertures is provided by the controlled negative angular orientation of the entry angle of the most upstream of the opposing aperture pairs thereby providing relative uniformity of the temperature of molten metal reaching each of the plurality of apertures. A unique unitized thimble configuration and trough damming arrangement are also described.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a metal distribution system of the prior art.
FIG. 2 is a top view of one embodiment of the metal distribution system of the present invention.
FIG. 3 is a cross-sectional view of a mold of the prior art.
FIG. 4 is a cross-sectional view of one embodiment of a mold of the present invention.
FIG. 5 is a top plan view of a single secondary trough in accordance with the present invention.
DETAILED DESCRIPTION
Referring now to FIG. 1 , in the prior art a metal distribution system 10 for the simultaneous production of multiple logs or round billets comprised an inlet 12 feeding a primary trough 14 that in turn fed secondary troughs 16 a , 16 b and 16 c . Located at approximately right angles to the major (long) axes 18 a , 18 b and 18 c of secondary troughs 16 a , 16 b and 16 c and on opposing sides thereof are pairs of opposed round apertures 20 (only some being specifically identified in FIG. 1 for clarity) each of apertures 20 containing a mold as will be described below in connection with FIG. 3 . Insertion of manual dams 22 requires manual removal to begin the flow of metal into troughs 16 a , 16 b and 16 c . In the casting operation, molten metal was provide to primary trough 14 , passed therethrough to secondary troughs 16 a , 16 b and 16 c and thence into apertures 20 . While, as previously mentioned such a structure has provided a highly useful arrangement, it did demonstrate several shortcomings. Among these were that all of apertures 20 did not fill at the same time, thus resulting in temperature and solidification differences inside the sump between the first and last to fill in molten metal entering, for example the aperture designated 20 a and that designated 20 b in FIG. 1 . Such a condition can and often did lead to the problems previously referred to as “bleedout” or “freeze-in”. Additionally, the casting practice commonly used with a metal distribution system of this type called for starting the flow of molten metal through inlet 12 and then sequentially and manually removing dams 22 . The need to manually operate the damming arrangement required the presence of operators, most generally 2 on the surface of casting table 10 to perform removal of the dams. This posed a significant safety hazard as the presence of personnel in the immediate area of the casting table is always a cause for safety concern. Thus, the design and availability of a casting table that eliminated such issues have been a long sought after objectives.
Referring now to FIG. 2 that presents a top plan view of the metal distribution system 30 of the present invention, there is provided an inlet 32 feeding a single preferably centrally located primary trough 34 having a plurality of relatively short secondary troughs 36 each feeding a plurality of opposing apertures 38 (not all numbered in FIG. 2 for clarity) that contain molds (not shown in FIG. 2 ). Dams 40 are provided at the entry of each of secondary troughs 36 . Dams 40 are controlled by a pneumatically or hydraulically operated dam control arm 42 that is remotely operated from an operators station (not shown). In operation, molten metal is flowed through inlet 32 into primary trough 34 where its flow is limited by the presence of dams 40 . Once primary trough 34 is filled to the appropriate level, dam control arm 43 is activated raising dams 40 allowing metal to flow simultaneously into all or selected secondary troughs 36 and thence into apertures/molds 38 . Thus, primary trough 34 and secondary troughs 36 are flowably connected. Because of the angular structure of entry angles 42 as described in greater detail below, molten metal of all relatively the same fill time and temperature rapidly fills apertures/molds 38 simultaneously thereby eliminating the problems of unequal temperature metal in the casting table at different locations, i.e. providing minimum fill time and accompanying minimum temperature loss with maximum velocity to avoid flashing. The incorporation of the remotely operated dams 40 , the need for the presence of operators on the casting table during the start up procedure is also eliminated.
Referring now to FIGS. 4 and 5 , according to a specifically preferred embodiment of the present invention, aperture entry angles 42 located at the entry of apertures 38 those proximate primary trough 34 , i.e. those at the upstream end 37 of secondary troughs 36 , are negative and preferably range from about 15 to about 30 degrees and most preferably between about 20 and 25 degrees. The negative orientation of these angles and their particular pitch as specified herein provide for the rapid and uniform fill of apertures 38 downstream thereof toward extremities 44 with a minimum of metal fill time and velocity into apertures 38 thus preventing metal flash and inclusion causing turbulence and providing relative temperature uniformity in the molten metal. Stated differently, filling of secondary troughs 36 , because of the angular orientation of entry angles 42 results in secondary troughs 36 filling from the downstream ends 44 toward the upstream ends 37 . In operation, as molten metal enters secondary troughs 36 upon the raising of dams 40 molten metal immediately flows to the outermost extremities or downstream ends 44 of secondary troughs 36 whereupon it quickly fills apertures 38 further downstream of primary trough 34 and then commences to fill secondary troughs 36 “backwards” in the direction of primary trough 34 or the upstream ends of secondary troughs 36 . This action provides for the quick and controlled fill of all apertures 38 with a minimum of turbulence and with molten metal of relatively the same temperature to assure a uniform start to the cast with a minimum of the occurrence of “bleedthrough” or “freeze-in” and significant reductions in head and butt defects that reduce the need for head and butt crop and increase the productivity of the casting operation. Thus, relatively simultaneous fill time of all apertures 38 is achieved by the provision of negative entry angles 42 that are directed away from opposing apertures 38 closest to primary trough 34 thus insuring that the positions 38 furthest away from primary trough 34 , i.e, closest to extremities 44 or downstream, receive metal at approximately the same time as those closest to primary trough 34 or upstream.
Each of apertures 20 and 38 contains a “mold”. As shown in FIG. 3 , (a cross-sectional view along the line 3 — 3 of FIG. 1 ) in the prior art, mold 50 comprised a crossfeeder 52 , a thimble 54 , a blanket of back-up insulation 56 , a “paper” (mica or the like) or similar gasket 58 , a transition plate 60 , a mold body 64 and a graphite ring 62 . A water reservoir 66 that produced a water spray 68 through the emission of water through spray channel 70 provided cooling of the solidifying metal 72 . The letters L and L′ in FIG. 3 indicates those areas where molten metal remains liquid as it moves through mold 50 before solidifying at 72 . The volume L′ is commonly referred to as the “sump”.
In the prior art, thimble 54 , crossfeeder 52 , back-up insulation 56 and transition plate 60 all represented individual components that were assembled “in situ” so to speak at the casting station or in a fabrication shop before the start-up of a cast. This clearly involved a significant amount of labor. Additionally, it was not uncommon for the vertical joint 74 between thimble 54 and crossfeeder 52 to leak resulting in a bleedthrough of molten metal into joint 76 at gasket 58 between crossfeeder 52 and blanket insulation 56 and casting table structure 78 . Such leakage was not only affected productivity, but could cause a safety issue under certain particularly severe leakage conditions. Additionally, the variability in assembly technique from operator to operator introduced a further element of uncertainty or variability into a casting operation that was already fraught with variables. Thus, a solution has been sought that would significantly reduce the labor intensity of the mold insertion/fabrication operation, reduce any variability in the assembly operation and reduce the potential for leakage at the previously described assembly joint(s).
Such a solution is shown in FIG. 4 that is a cross-sectional representation along the line 4 — 4 of FIG. 2 . The improved metal handling system 80 of the present invention shown in FIG. 4 also comprises a crossfeeder 82 , back-up insulation 84 , and a thimble 86 , but all fabricated as a monolith that simply drops into aperture 38 through horizontal engagement with mold table 88 at horizontal joint 90 and transition plate 78 that is part of mold 60 that further engages mold table bottom plate 62 supported on mold member 73 . The entire structure is retained in close and tight engagement through the action of a bolt down arrangement through steel upright 100 that includes a nut 102 or other suitable fastening arrangement to bring the entire structure together. A graphite lubricating ring 62 as used in the prior art is incorporated in much the same fashion and for the same purposes as in the prior art. Cooling water sprays and a water reservoir are also preferably incorporated into the mold assembly, as shown in FIG. 4 . The foregoing structure, has been found to: 1) reduce heat loss through the back-up insulation to a greater degree than the blanket back-up insulation used in the prior art; 2) results in fewer cracked logs at start up; 3) results in fewer cold start related defects such as bleedouts and freeze ins; and 4) quite obviously increases the ease of assembly, and greatly reduces the labor involved in the mold assembly operation.
What clearly differentiates refractory module 80 of the present invention is that it comprises a module that combines in a single integral unit, a hot face refractory for crossfeeder 82 and thimble 86 , with a peripheral, low density, cold face refractory, back-up insulation 84 thereby eliminating the need to separately insulate behind crossfeeder 82 and thimble 86 or to assemble the individual elements at the casting station or at some remote location. It also eliminates the need for a separate vertical joint ( 74 in FIG. 3 ) since thimble 86 is cast into the refractory module 80 providing the formation of a horizontal seal 90 (rather than a vertical seal) directly with the transition plate 78 .
The aim of the crossfeeder is mainly to distribute molten aluminum to the mold while minimizing turbulence and heat losses. The refractory material should be inert vis-à-vis molten aluminum, easy to clean and show a low heat storage. Prior art cross-feeders are made of light density refractories that have to be well preheated to avoid cold start-up. Depending on the material and design, maintenance can be quite extensive. The main mode of failure in such devices is crack propagation with time that renders the crossfeeder unusable. Typical life is difficult to determine because it depends on many variables such as: casting technology, design, casting parameters, maintenance, etc.
According to the present invention, two different refractory materials are used to extend the useful life of the crossfeeder and to enhance the aluminum casting process itself.
The material directly in contact with the aluminum 87 is a dense and hard refractory material showing excellent non-wetting characteristics to molten aluminum. It is provided in the form a thin skin, preferably between 6 and 10 mm thick. This material is a fiberglass fabric reinforced wollastonite that exhibits outstanding mechanical and non-wetting properties and is suitable for the fabrication of complex shapes. According to a highly preferred embodiment of the present invention the non-wetting properties of this material are further improved by coating its surface with a thin layer of boron nitride (not shown). Thin skin 87 is then backed up with a layer 84 of a highly insulating refractory material, preferably, Wollite, a mineral foam based wollastonite material. The skin 87 is used as the mold external surface and the Wollite insulation 84 is cast around this externally. The two materials constituting thin skin 87 and insulating refractory 84 , have very similar thermal expansion coefficients, which avoids delamination and cracking during the heat up and casting cycles. This material combination exhibits a number of desirable characteristics/advantages. Among these are: mechanical strength; crack propagation minimization because of structure; repairability; reduced heat transfer and therefore more consistent molten metal temperature; significantly reduced cross-feeder weight and casting table weight significantly reduced heat storage and table preheating schedule; and reduced steel shell temperature due to increased insulation factors thereby minimizing steel expansion, joint maintenance and crack propagation.
Thus, in the casting insert 80 of the present invention, cylindrical crossfeeder 82 and cylindrical thimble 86 present a continuous, joint free and uninterrupted cylindrical interior surface 87 surrounded by an integral peripheral layer of back-up insulation 84 .
While the elements of the monolithic assembly of the present invention can be fabricated from a wide variety of compatible materials, according to a highly preferred embodiment of the invention, crossfeeder 82 is formed from an SH or RFM Insural material available from Pyrotek, Inc. East 9503 Montgomery Ave, Spokane, Wash. RFM Insural is a moldable light density refractory composite material comprised of fiberglass fabric reinforced wollastonite. Back-up insulation 84 comprises Wollite an insulating castable also available from Pyrotek, Inc. Wollite is a solid lightweight mineral foam that is stable during its preparation and during curing and drying. It is a phosphate bonded foam insulation that can be made in densities ranging from 320 to 880 kg/m 3 and is mainly composed of wollastonite, a calcium silicate. Crossfeeder 82 , thimble 86 and backup insulation 84 can also be cast as a single unit. This is made possible by the compatibility of the various materials of fabrication.
There have thus been described: a novel metal distribution system incorporating; an automated and remotely operable dam removal system; and a monolithic mold insert assembly that each individually demonstrate significant operating advantages and which when combined into a single operating system provide a significantly improved log or round ingot casting system that is economically desirable and simultaneously provides noteworthy safety improvements.
As the invention has been described, it will be apparent to those skilled in the art that the same may be varied in any ways without departing from the spirit and scope thereof. Any and all such modifications are intended to be included within the scope of the appended claims. | A metal distribution system for the simultaneous production of a plurality of logs or round billets from molten metal comprising: 1) a trough for the introduction of molten metal; 2) a plurality of side streams extending from the trough and each of the side streams including a plurality of opposing apertures each of the apertures including a thimble for the shaping of molten metal passing through the trough and the side streams and into the thimbles. A uniform flow of molten metal into the side streams and the individual apertures is provided by the controlled negative angular orientation of the most upstream opposing pair of apertures thereby providing relative uniformity of the temperature of molten metal reaching each of the plurality of apertures. A unique unitized thimble configuration and trough damming arrangement are also described. | 1 |
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